1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/sched.h>
7 #include <linux/sched/mm.h>
8 #include <linux/slab.h>
9 #include <linux/ratelimit.h>
10 #include <linux/kthread.h>
11 #include <linux/semaphore.h>
12 #include <linux/uuid.h>
13 #include <linux/list_sort.h>
14 #include <linux/namei.h>
15 #include "misc.h"
16 #include "disk-io.h"
17 #include "extent-tree.h"
18 #include "transaction.h"
19 #include "volumes.h"
20 #include "raid56.h"
21 #include "rcu-string.h"
22 #include "dev-replace.h"
23 #include "sysfs.h"
24 #include "tree-checker.h"
25 #include "space-info.h"
26 #include "block-group.h"
27 #include "discard.h"
28 #include "zoned.h"
29 #include "fs.h"
30 #include "accessors.h"
31 #include "uuid-tree.h"
32 #include "ioctl.h"
33 #include "relocation.h"
34 #include "scrub.h"
35 #include "super.h"
36 #include "raid-stripe-tree.h"
37
38 #define BTRFS_BLOCK_GROUP_STRIPE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \
39 BTRFS_BLOCK_GROUP_RAID10 | \
40 BTRFS_BLOCK_GROUP_RAID56_MASK)
41
42 struct btrfs_io_geometry {
43 u32 stripe_index;
44 u32 stripe_nr;
45 int mirror_num;
46 int num_stripes;
47 u64 stripe_offset;
48 u64 raid56_full_stripe_start;
49 int max_errors;
50 enum btrfs_map_op op;
51 bool use_rst;
52 };
53
54 const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
55 [BTRFS_RAID_RAID10] = {
56 .sub_stripes = 2,
57 .dev_stripes = 1,
58 .devs_max = 0, /* 0 == as many as possible */
59 .devs_min = 2,
60 .tolerated_failures = 1,
61 .devs_increment = 2,
62 .ncopies = 2,
63 .nparity = 0,
64 .raid_name = "raid10",
65 .bg_flag = BTRFS_BLOCK_GROUP_RAID10,
66 .mindev_error = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET,
67 },
68 [BTRFS_RAID_RAID1] = {
69 .sub_stripes = 1,
70 .dev_stripes = 1,
71 .devs_max = 2,
72 .devs_min = 2,
73 .tolerated_failures = 1,
74 .devs_increment = 2,
75 .ncopies = 2,
76 .nparity = 0,
77 .raid_name = "raid1",
78 .bg_flag = BTRFS_BLOCK_GROUP_RAID1,
79 .mindev_error = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET,
80 },
81 [BTRFS_RAID_RAID1C3] = {
82 .sub_stripes = 1,
83 .dev_stripes = 1,
84 .devs_max = 3,
85 .devs_min = 3,
86 .tolerated_failures = 2,
87 .devs_increment = 3,
88 .ncopies = 3,
89 .nparity = 0,
90 .raid_name = "raid1c3",
91 .bg_flag = BTRFS_BLOCK_GROUP_RAID1C3,
92 .mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET,
93 },
94 [BTRFS_RAID_RAID1C4] = {
95 .sub_stripes = 1,
96 .dev_stripes = 1,
97 .devs_max = 4,
98 .devs_min = 4,
99 .tolerated_failures = 3,
100 .devs_increment = 4,
101 .ncopies = 4,
102 .nparity = 0,
103 .raid_name = "raid1c4",
104 .bg_flag = BTRFS_BLOCK_GROUP_RAID1C4,
105 .mindev_error = BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET,
106 },
107 [BTRFS_RAID_DUP] = {
108 .sub_stripes = 1,
109 .dev_stripes = 2,
110 .devs_max = 1,
111 .devs_min = 1,
112 .tolerated_failures = 0,
113 .devs_increment = 1,
114 .ncopies = 2,
115 .nparity = 0,
116 .raid_name = "dup",
117 .bg_flag = BTRFS_BLOCK_GROUP_DUP,
118 .mindev_error = 0,
119 },
120 [BTRFS_RAID_RAID0] = {
121 .sub_stripes = 1,
122 .dev_stripes = 1,
123 .devs_max = 0,
124 .devs_min = 1,
125 .tolerated_failures = 0,
126 .devs_increment = 1,
127 .ncopies = 1,
128 .nparity = 0,
129 .raid_name = "raid0",
130 .bg_flag = BTRFS_BLOCK_GROUP_RAID0,
131 .mindev_error = 0,
132 },
133 [BTRFS_RAID_SINGLE] = {
134 .sub_stripes = 1,
135 .dev_stripes = 1,
136 .devs_max = 1,
137 .devs_min = 1,
138 .tolerated_failures = 0,
139 .devs_increment = 1,
140 .ncopies = 1,
141 .nparity = 0,
142 .raid_name = "single",
143 .bg_flag = 0,
144 .mindev_error = 0,
145 },
146 [BTRFS_RAID_RAID5] = {
147 .sub_stripes = 1,
148 .dev_stripes = 1,
149 .devs_max = 0,
150 .devs_min = 2,
151 .tolerated_failures = 1,
152 .devs_increment = 1,
153 .ncopies = 1,
154 .nparity = 1,
155 .raid_name = "raid5",
156 .bg_flag = BTRFS_BLOCK_GROUP_RAID5,
157 .mindev_error = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET,
158 },
159 [BTRFS_RAID_RAID6] = {
160 .sub_stripes = 1,
161 .dev_stripes = 1,
162 .devs_max = 0,
163 .devs_min = 3,
164 .tolerated_failures = 2,
165 .devs_increment = 1,
166 .ncopies = 1,
167 .nparity = 2,
168 .raid_name = "raid6",
169 .bg_flag = BTRFS_BLOCK_GROUP_RAID6,
170 .mindev_error = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET,
171 },
172 };
173
174 /*
175 * Convert block group flags (BTRFS_BLOCK_GROUP_*) to btrfs_raid_types, which
176 * can be used as index to access btrfs_raid_array[].
177 */
btrfs_bg_flags_to_raid_index(u64 flags)178 enum btrfs_raid_types __attribute_const__ btrfs_bg_flags_to_raid_index(u64 flags)
179 {
180 const u64 profile = (flags & BTRFS_BLOCK_GROUP_PROFILE_MASK);
181
182 if (!profile)
183 return BTRFS_RAID_SINGLE;
184
185 return BTRFS_BG_FLAG_TO_INDEX(profile);
186 }
187
btrfs_bg_type_to_raid_name(u64 flags)188 const char *btrfs_bg_type_to_raid_name(u64 flags)
189 {
190 const int index = btrfs_bg_flags_to_raid_index(flags);
191
192 if (index >= BTRFS_NR_RAID_TYPES)
193 return NULL;
194
195 return btrfs_raid_array[index].raid_name;
196 }
197
btrfs_nr_parity_stripes(u64 type)198 int btrfs_nr_parity_stripes(u64 type)
199 {
200 enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(type);
201
202 return btrfs_raid_array[index].nparity;
203 }
204
205 /*
206 * Fill @buf with textual description of @bg_flags, no more than @size_buf
207 * bytes including terminating null byte.
208 */
btrfs_describe_block_groups(u64 bg_flags,char * buf,u32 size_buf)209 void btrfs_describe_block_groups(u64 bg_flags, char *buf, u32 size_buf)
210 {
211 int i;
212 int ret;
213 char *bp = buf;
214 u64 flags = bg_flags;
215 u32 size_bp = size_buf;
216
217 if (!flags) {
218 strcpy(bp, "NONE");
219 return;
220 }
221
222 #define DESCRIBE_FLAG(flag, desc) \
223 do { \
224 if (flags & (flag)) { \
225 ret = snprintf(bp, size_bp, "%s|", (desc)); \
226 if (ret < 0 || ret >= size_bp) \
227 goto out_overflow; \
228 size_bp -= ret; \
229 bp += ret; \
230 flags &= ~(flag); \
231 } \
232 } while (0)
233
234 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_DATA, "data");
235 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_SYSTEM, "system");
236 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_METADATA, "metadata");
237
238 DESCRIBE_FLAG(BTRFS_AVAIL_ALLOC_BIT_SINGLE, "single");
239 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
240 DESCRIBE_FLAG(btrfs_raid_array[i].bg_flag,
241 btrfs_raid_array[i].raid_name);
242 #undef DESCRIBE_FLAG
243
244 if (flags) {
245 ret = snprintf(bp, size_bp, "0x%llx|", flags);
246 size_bp -= ret;
247 }
248
249 if (size_bp < size_buf)
250 buf[size_buf - size_bp - 1] = '\0'; /* remove last | */
251
252 /*
253 * The text is trimmed, it's up to the caller to provide sufficiently
254 * large buffer
255 */
256 out_overflow:;
257 }
258
259 static int init_first_rw_device(struct btrfs_trans_handle *trans);
260 static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info);
261 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
262
263 /*
264 * Device locking
265 * ==============
266 *
267 * There are several mutexes that protect manipulation of devices and low-level
268 * structures like chunks but not block groups, extents or files
269 *
270 * uuid_mutex (global lock)
271 * ------------------------
272 * protects the fs_uuids list that tracks all per-fs fs_devices, resulting from
273 * the SCAN_DEV ioctl registration or from mount either implicitly (the first
274 * device) or requested by the device= mount option
275 *
276 * the mutex can be very coarse and can cover long-running operations
277 *
278 * protects: updates to fs_devices counters like missing devices, rw devices,
279 * seeding, structure cloning, opening/closing devices at mount/umount time
280 *
281 * global::fs_devs - add, remove, updates to the global list
282 *
283 * does not protect: manipulation of the fs_devices::devices list in general
284 * but in mount context it could be used to exclude list modifications by eg.
285 * scan ioctl
286 *
287 * btrfs_device::name - renames (write side), read is RCU
288 *
289 * fs_devices::device_list_mutex (per-fs, with RCU)
290 * ------------------------------------------------
291 * protects updates to fs_devices::devices, ie. adding and deleting
292 *
293 * simple list traversal with read-only actions can be done with RCU protection
294 *
295 * may be used to exclude some operations from running concurrently without any
296 * modifications to the list (see write_all_supers)
297 *
298 * Is not required at mount and close times, because our device list is
299 * protected by the uuid_mutex at that point.
300 *
301 * balance_mutex
302 * -------------
303 * protects balance structures (status, state) and context accessed from
304 * several places (internally, ioctl)
305 *
306 * chunk_mutex
307 * -----------
308 * protects chunks, adding or removing during allocation, trim or when a new
309 * device is added/removed. Additionally it also protects post_commit_list of
310 * individual devices, since they can be added to the transaction's
311 * post_commit_list only with chunk_mutex held.
312 *
313 * cleaner_mutex
314 * -------------
315 * a big lock that is held by the cleaner thread and prevents running subvolume
316 * cleaning together with relocation or delayed iputs
317 *
318 *
319 * Lock nesting
320 * ============
321 *
322 * uuid_mutex
323 * device_list_mutex
324 * chunk_mutex
325 * balance_mutex
326 *
327 *
328 * Exclusive operations
329 * ====================
330 *
331 * Maintains the exclusivity of the following operations that apply to the
332 * whole filesystem and cannot run in parallel.
333 *
334 * - Balance (*)
335 * - Device add
336 * - Device remove
337 * - Device replace (*)
338 * - Resize
339 *
340 * The device operations (as above) can be in one of the following states:
341 *
342 * - Running state
343 * - Paused state
344 * - Completed state
345 *
346 * Only device operations marked with (*) can go into the Paused state for the
347 * following reasons:
348 *
349 * - ioctl (only Balance can be Paused through ioctl)
350 * - filesystem remounted as read-only
351 * - filesystem unmounted and mounted as read-only
352 * - system power-cycle and filesystem mounted as read-only
353 * - filesystem or device errors leading to forced read-only
354 *
355 * The status of exclusive operation is set and cleared atomically.
356 * During the course of Paused state, fs_info::exclusive_operation remains set.
357 * A device operation in Paused or Running state can be canceled or resumed
358 * either by ioctl (Balance only) or when remounted as read-write.
359 * The exclusive status is cleared when the device operation is canceled or
360 * completed.
361 */
362
363 DEFINE_MUTEX(uuid_mutex);
364 static LIST_HEAD(fs_uuids);
btrfs_get_fs_uuids(void)365 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void)
366 {
367 return &fs_uuids;
368 }
369
370 /*
371 * Allocate new btrfs_fs_devices structure identified by a fsid.
372 *
373 * @fsid: if not NULL, copy the UUID to fs_devices::fsid and to
374 * fs_devices::metadata_fsid
375 *
376 * Return a pointer to a new struct btrfs_fs_devices on success, or ERR_PTR().
377 * The returned struct is not linked onto any lists and can be destroyed with
378 * kfree() right away.
379 */
alloc_fs_devices(const u8 * fsid)380 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
381 {
382 struct btrfs_fs_devices *fs_devs;
383
384 fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL);
385 if (!fs_devs)
386 return ERR_PTR(-ENOMEM);
387
388 mutex_init(&fs_devs->device_list_mutex);
389
390 INIT_LIST_HEAD(&fs_devs->devices);
391 INIT_LIST_HEAD(&fs_devs->alloc_list);
392 INIT_LIST_HEAD(&fs_devs->fs_list);
393 INIT_LIST_HEAD(&fs_devs->seed_list);
394
395 if (fsid) {
396 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
397 memcpy(fs_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE);
398 }
399
400 return fs_devs;
401 }
402
btrfs_free_device(struct btrfs_device * device)403 static void btrfs_free_device(struct btrfs_device *device)
404 {
405 WARN_ON(!list_empty(&device->post_commit_list));
406 rcu_string_free(device->name);
407 extent_io_tree_release(&device->alloc_state);
408 btrfs_destroy_dev_zone_info(device);
409 kfree(device);
410 }
411
free_fs_devices(struct btrfs_fs_devices * fs_devices)412 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
413 {
414 struct btrfs_device *device;
415
416 WARN_ON(fs_devices->opened);
417 while (!list_empty(&fs_devices->devices)) {
418 device = list_entry(fs_devices->devices.next,
419 struct btrfs_device, dev_list);
420 list_del(&device->dev_list);
421 btrfs_free_device(device);
422 }
423 kfree(fs_devices);
424 }
425
btrfs_cleanup_fs_uuids(void)426 void __exit btrfs_cleanup_fs_uuids(void)
427 {
428 struct btrfs_fs_devices *fs_devices;
429
430 while (!list_empty(&fs_uuids)) {
431 fs_devices = list_entry(fs_uuids.next,
432 struct btrfs_fs_devices, fs_list);
433 list_del(&fs_devices->fs_list);
434 free_fs_devices(fs_devices);
435 }
436 }
437
match_fsid_fs_devices(const struct btrfs_fs_devices * fs_devices,const u8 * fsid,const u8 * metadata_fsid)438 static bool match_fsid_fs_devices(const struct btrfs_fs_devices *fs_devices,
439 const u8 *fsid, const u8 *metadata_fsid)
440 {
441 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) != 0)
442 return false;
443
444 if (!metadata_fsid)
445 return true;
446
447 if (memcmp(metadata_fsid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE) != 0)
448 return false;
449
450 return true;
451 }
452
find_fsid(const u8 * fsid,const u8 * metadata_fsid)453 static noinline struct btrfs_fs_devices *find_fsid(
454 const u8 *fsid, const u8 *metadata_fsid)
455 {
456 struct btrfs_fs_devices *fs_devices;
457
458 ASSERT(fsid);
459
460 /* Handle non-split brain cases */
461 list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
462 if (match_fsid_fs_devices(fs_devices, fsid, metadata_fsid))
463 return fs_devices;
464 }
465 return NULL;
466 }
467
468 static int
btrfs_get_bdev_and_sb(const char * device_path,blk_mode_t flags,void * holder,int flush,struct file ** bdev_file,struct btrfs_super_block ** disk_super)469 btrfs_get_bdev_and_sb(const char *device_path, blk_mode_t flags, void *holder,
470 int flush, struct file **bdev_file,
471 struct btrfs_super_block **disk_super)
472 {
473 struct block_device *bdev;
474 int ret;
475
476 *bdev_file = bdev_file_open_by_path(device_path, flags, holder, NULL);
477
478 if (IS_ERR(*bdev_file)) {
479 ret = PTR_ERR(*bdev_file);
480 btrfs_err(NULL, "failed to open device for path %s with flags 0x%x: %d",
481 device_path, flags, ret);
482 goto error;
483 }
484 bdev = file_bdev(*bdev_file);
485
486 if (flush)
487 sync_blockdev(bdev);
488 if (holder) {
489 ret = set_blocksize(*bdev_file, BTRFS_BDEV_BLOCKSIZE);
490 if (ret) {
491 fput(*bdev_file);
492 goto error;
493 }
494 }
495 invalidate_bdev(bdev);
496 *disk_super = btrfs_read_dev_super(bdev);
497 if (IS_ERR(*disk_super)) {
498 ret = PTR_ERR(*disk_super);
499 fput(*bdev_file);
500 goto error;
501 }
502
503 return 0;
504
505 error:
506 *disk_super = NULL;
507 *bdev_file = NULL;
508 return ret;
509 }
510
511 /*
512 * Search and remove all stale devices (which are not mounted). When both
513 * inputs are NULL, it will search and release all stale devices.
514 *
515 * @devt: Optional. When provided will it release all unmounted devices
516 * matching this devt only.
517 * @skip_device: Optional. Will skip this device when searching for the stale
518 * devices.
519 *
520 * Return: 0 for success or if @devt is 0.
521 * -EBUSY if @devt is a mounted device.
522 * -ENOENT if @devt does not match any device in the list.
523 */
btrfs_free_stale_devices(dev_t devt,struct btrfs_device * skip_device)524 static int btrfs_free_stale_devices(dev_t devt, struct btrfs_device *skip_device)
525 {
526 struct btrfs_fs_devices *fs_devices, *tmp_fs_devices;
527 struct btrfs_device *device, *tmp_device;
528 int ret;
529 bool freed = false;
530
531 lockdep_assert_held(&uuid_mutex);
532
533 /* Return good status if there is no instance of devt. */
534 ret = 0;
535 list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) {
536
537 mutex_lock(&fs_devices->device_list_mutex);
538 list_for_each_entry_safe(device, tmp_device,
539 &fs_devices->devices, dev_list) {
540 if (skip_device && skip_device == device)
541 continue;
542 if (devt && devt != device->devt)
543 continue;
544 if (fs_devices->opened) {
545 if (devt)
546 ret = -EBUSY;
547 break;
548 }
549
550 /* delete the stale device */
551 fs_devices->num_devices--;
552 list_del(&device->dev_list);
553 btrfs_free_device(device);
554
555 freed = true;
556 }
557 mutex_unlock(&fs_devices->device_list_mutex);
558
559 if (fs_devices->num_devices == 0) {
560 btrfs_sysfs_remove_fsid(fs_devices);
561 list_del(&fs_devices->fs_list);
562 free_fs_devices(fs_devices);
563 }
564 }
565
566 /* If there is at least one freed device return 0. */
567 if (freed)
568 return 0;
569
570 return ret;
571 }
572
find_fsid_by_device(struct btrfs_super_block * disk_super,dev_t devt,bool * same_fsid_diff_dev)573 static struct btrfs_fs_devices *find_fsid_by_device(
574 struct btrfs_super_block *disk_super,
575 dev_t devt, bool *same_fsid_diff_dev)
576 {
577 struct btrfs_fs_devices *fsid_fs_devices;
578 struct btrfs_fs_devices *devt_fs_devices;
579 const bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
580 BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
581 bool found_by_devt = false;
582
583 /* Find the fs_device by the usual method, if found use it. */
584 fsid_fs_devices = find_fsid(disk_super->fsid,
585 has_metadata_uuid ? disk_super->metadata_uuid : NULL);
586
587 /* The temp_fsid feature is supported only with single device filesystem. */
588 if (btrfs_super_num_devices(disk_super) != 1)
589 return fsid_fs_devices;
590
591 /*
592 * A seed device is an integral component of the sprout device, which
593 * functions as a multi-device filesystem. So, temp-fsid feature is
594 * not supported.
595 */
596 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING)
597 return fsid_fs_devices;
598
599 /* Try to find a fs_devices by matching devt. */
600 list_for_each_entry(devt_fs_devices, &fs_uuids, fs_list) {
601 struct btrfs_device *device;
602
603 list_for_each_entry(device, &devt_fs_devices->devices, dev_list) {
604 if (device->devt == devt) {
605 found_by_devt = true;
606 break;
607 }
608 }
609 if (found_by_devt)
610 break;
611 }
612
613 if (found_by_devt) {
614 /* Existing device. */
615 if (fsid_fs_devices == NULL) {
616 if (devt_fs_devices->opened == 0) {
617 /* Stale device. */
618 return NULL;
619 } else {
620 /* temp_fsid is mounting a subvol. */
621 return devt_fs_devices;
622 }
623 } else {
624 /* Regular or temp_fsid device mounting a subvol. */
625 return devt_fs_devices;
626 }
627 } else {
628 /* New device. */
629 if (fsid_fs_devices == NULL) {
630 return NULL;
631 } else {
632 /* sb::fsid is already used create a new temp_fsid. */
633 *same_fsid_diff_dev = true;
634 return NULL;
635 }
636 }
637
638 /* Not reached. */
639 }
640
641 /*
642 * This is only used on mount, and we are protected from competing things
643 * messing with our fs_devices by the uuid_mutex, thus we do not need the
644 * fs_devices->device_list_mutex here.
645 */
btrfs_open_one_device(struct btrfs_fs_devices * fs_devices,struct btrfs_device * device,blk_mode_t flags,void * holder)646 static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
647 struct btrfs_device *device, blk_mode_t flags,
648 void *holder)
649 {
650 struct file *bdev_file;
651 struct btrfs_super_block *disk_super;
652 u64 devid;
653 int ret;
654
655 if (device->bdev)
656 return -EINVAL;
657 if (!device->name)
658 return -EINVAL;
659
660 ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
661 &bdev_file, &disk_super);
662 if (ret)
663 return ret;
664
665 devid = btrfs_stack_device_id(&disk_super->dev_item);
666 if (devid != device->devid)
667 goto error_free_page;
668
669 if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE))
670 goto error_free_page;
671
672 device->generation = btrfs_super_generation(disk_super);
673
674 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
675 if (btrfs_super_incompat_flags(disk_super) &
676 BTRFS_FEATURE_INCOMPAT_METADATA_UUID) {
677 pr_err(
678 "BTRFS: Invalid seeding and uuid-changed device detected\n");
679 goto error_free_page;
680 }
681
682 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
683 fs_devices->seeding = true;
684 } else {
685 if (bdev_read_only(file_bdev(bdev_file)))
686 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
687 else
688 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
689 }
690
691 if (!bdev_nonrot(file_bdev(bdev_file)))
692 fs_devices->rotating = true;
693
694 if (bdev_max_discard_sectors(file_bdev(bdev_file)))
695 fs_devices->discardable = true;
696
697 device->bdev_file = bdev_file;
698 device->bdev = file_bdev(bdev_file);
699 clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
700
701 if (device->devt != device->bdev->bd_dev) {
702 btrfs_warn(NULL,
703 "device %s maj:min changed from %d:%d to %d:%d",
704 device->name->str, MAJOR(device->devt),
705 MINOR(device->devt), MAJOR(device->bdev->bd_dev),
706 MINOR(device->bdev->bd_dev));
707
708 device->devt = device->bdev->bd_dev;
709 }
710
711 fs_devices->open_devices++;
712 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
713 device->devid != BTRFS_DEV_REPLACE_DEVID) {
714 fs_devices->rw_devices++;
715 list_add_tail(&device->dev_alloc_list, &fs_devices->alloc_list);
716 }
717 btrfs_release_disk_super(disk_super);
718
719 return 0;
720
721 error_free_page:
722 btrfs_release_disk_super(disk_super);
723 fput(bdev_file);
724
725 return -EINVAL;
726 }
727
btrfs_sb_fsid_ptr(const struct btrfs_super_block * sb)728 const u8 *btrfs_sb_fsid_ptr(const struct btrfs_super_block *sb)
729 {
730 bool has_metadata_uuid = (btrfs_super_incompat_flags(sb) &
731 BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
732
733 return has_metadata_uuid ? sb->metadata_uuid : sb->fsid;
734 }
735
is_same_device(struct btrfs_device * device,const char * new_path)736 static bool is_same_device(struct btrfs_device *device, const char *new_path)
737 {
738 struct path old = { .mnt = NULL, .dentry = NULL };
739 struct path new = { .mnt = NULL, .dentry = NULL };
740 char *old_path = NULL;
741 bool is_same = false;
742 int ret;
743
744 if (!device->name)
745 goto out;
746
747 old_path = kzalloc(PATH_MAX, GFP_NOFS);
748 if (!old_path)
749 goto out;
750
751 rcu_read_lock();
752 ret = strscpy(old_path, rcu_str_deref(device->name), PATH_MAX);
753 rcu_read_unlock();
754 if (ret < 0)
755 goto out;
756
757 ret = kern_path(old_path, LOOKUP_FOLLOW, &old);
758 if (ret)
759 goto out;
760 ret = kern_path(new_path, LOOKUP_FOLLOW, &new);
761 if (ret)
762 goto out;
763 if (path_equal(&old, &new))
764 is_same = true;
765 out:
766 kfree(old_path);
767 path_put(&old);
768 path_put(&new);
769 return is_same;
770 }
771
772 /*
773 * Add new device to list of registered devices
774 *
775 * Returns:
776 * device pointer which was just added or updated when successful
777 * error pointer when failed
778 */
device_list_add(const char * path,struct btrfs_super_block * disk_super,bool * new_device_added)779 static noinline struct btrfs_device *device_list_add(const char *path,
780 struct btrfs_super_block *disk_super,
781 bool *new_device_added)
782 {
783 struct btrfs_device *device;
784 struct btrfs_fs_devices *fs_devices = NULL;
785 struct rcu_string *name;
786 u64 found_transid = btrfs_super_generation(disk_super);
787 u64 devid = btrfs_stack_device_id(&disk_super->dev_item);
788 dev_t path_devt;
789 int error;
790 bool same_fsid_diff_dev = false;
791 bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) &
792 BTRFS_FEATURE_INCOMPAT_METADATA_UUID);
793
794 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_CHANGING_FSID_V2) {
795 btrfs_err(NULL,
796 "device %s has incomplete metadata_uuid change, please use btrfstune to complete",
797 path);
798 return ERR_PTR(-EAGAIN);
799 }
800
801 error = lookup_bdev(path, &path_devt);
802 if (error) {
803 btrfs_err(NULL, "failed to lookup block device for path %s: %d",
804 path, error);
805 return ERR_PTR(error);
806 }
807
808 fs_devices = find_fsid_by_device(disk_super, path_devt, &same_fsid_diff_dev);
809
810 if (!fs_devices) {
811 fs_devices = alloc_fs_devices(disk_super->fsid);
812 if (IS_ERR(fs_devices))
813 return ERR_CAST(fs_devices);
814
815 if (has_metadata_uuid)
816 memcpy(fs_devices->metadata_uuid,
817 disk_super->metadata_uuid, BTRFS_FSID_SIZE);
818
819 if (same_fsid_diff_dev) {
820 generate_random_uuid(fs_devices->fsid);
821 fs_devices->temp_fsid = true;
822 pr_info("BTRFS: device %s (%d:%d) using temp-fsid %pU\n",
823 path, MAJOR(path_devt), MINOR(path_devt),
824 fs_devices->fsid);
825 }
826
827 mutex_lock(&fs_devices->device_list_mutex);
828 list_add(&fs_devices->fs_list, &fs_uuids);
829
830 device = NULL;
831 } else {
832 struct btrfs_dev_lookup_args args = {
833 .devid = devid,
834 .uuid = disk_super->dev_item.uuid,
835 };
836
837 mutex_lock(&fs_devices->device_list_mutex);
838 device = btrfs_find_device(fs_devices, &args);
839
840 if (found_transid > fs_devices->latest_generation) {
841 memcpy(fs_devices->fsid, disk_super->fsid,
842 BTRFS_FSID_SIZE);
843 memcpy(fs_devices->metadata_uuid,
844 btrfs_sb_fsid_ptr(disk_super), BTRFS_FSID_SIZE);
845 }
846 }
847
848 if (!device) {
849 unsigned int nofs_flag;
850
851 if (fs_devices->opened) {
852 btrfs_err(NULL,
853 "device %s (%d:%d) belongs to fsid %pU, and the fs is already mounted, scanned by %s (%d)",
854 path, MAJOR(path_devt), MINOR(path_devt),
855 fs_devices->fsid, current->comm,
856 task_pid_nr(current));
857 mutex_unlock(&fs_devices->device_list_mutex);
858 return ERR_PTR(-EBUSY);
859 }
860
861 nofs_flag = memalloc_nofs_save();
862 device = btrfs_alloc_device(NULL, &devid,
863 disk_super->dev_item.uuid, path);
864 memalloc_nofs_restore(nofs_flag);
865 if (IS_ERR(device)) {
866 mutex_unlock(&fs_devices->device_list_mutex);
867 /* we can safely leave the fs_devices entry around */
868 return device;
869 }
870
871 device->devt = path_devt;
872
873 list_add_rcu(&device->dev_list, &fs_devices->devices);
874 fs_devices->num_devices++;
875
876 device->fs_devices = fs_devices;
877 *new_device_added = true;
878
879 if (disk_super->label[0])
880 pr_info(
881 "BTRFS: device label %s devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n",
882 disk_super->label, devid, found_transid, path,
883 MAJOR(path_devt), MINOR(path_devt),
884 current->comm, task_pid_nr(current));
885 else
886 pr_info(
887 "BTRFS: device fsid %pU devid %llu transid %llu %s (%d:%d) scanned by %s (%d)\n",
888 disk_super->fsid, devid, found_transid, path,
889 MAJOR(path_devt), MINOR(path_devt),
890 current->comm, task_pid_nr(current));
891
892 } else if (!device->name || !is_same_device(device, path)) {
893 /*
894 * When FS is already mounted.
895 * 1. If you are here and if the device->name is NULL that
896 * means this device was missing at time of FS mount.
897 * 2. If you are here and if the device->name is different
898 * from 'path' that means either
899 * a. The same device disappeared and reappeared with
900 * different name. or
901 * b. The missing-disk-which-was-replaced, has
902 * reappeared now.
903 *
904 * We must allow 1 and 2a above. But 2b would be a spurious
905 * and unintentional.
906 *
907 * Further in case of 1 and 2a above, the disk at 'path'
908 * would have missed some transaction when it was away and
909 * in case of 2a the stale bdev has to be updated as well.
910 * 2b must not be allowed at all time.
911 */
912
913 /*
914 * For now, we do allow update to btrfs_fs_device through the
915 * btrfs dev scan cli after FS has been mounted. We're still
916 * tracking a problem where systems fail mount by subvolume id
917 * when we reject replacement on a mounted FS.
918 */
919 if (!fs_devices->opened && found_transid < device->generation) {
920 /*
921 * That is if the FS is _not_ mounted and if you
922 * are here, that means there is more than one
923 * disk with same uuid and devid.We keep the one
924 * with larger generation number or the last-in if
925 * generation are equal.
926 */
927 mutex_unlock(&fs_devices->device_list_mutex);
928 btrfs_err(NULL,
929 "device %s already registered with a higher generation, found %llu expect %llu",
930 path, found_transid, device->generation);
931 return ERR_PTR(-EEXIST);
932 }
933
934 /*
935 * We are going to replace the device path for a given devid,
936 * make sure it's the same device if the device is mounted
937 *
938 * NOTE: the device->fs_info may not be reliable here so pass
939 * in a NULL to message helpers instead. This avoids a possible
940 * use-after-free when the fs_info and fs_info->sb are already
941 * torn down.
942 */
943 if (device->bdev) {
944 if (device->devt != path_devt) {
945 mutex_unlock(&fs_devices->device_list_mutex);
946 btrfs_warn_in_rcu(NULL,
947 "duplicate device %s devid %llu generation %llu scanned by %s (%d)",
948 path, devid, found_transid,
949 current->comm,
950 task_pid_nr(current));
951 return ERR_PTR(-EEXIST);
952 }
953 btrfs_info_in_rcu(NULL,
954 "devid %llu device path %s changed to %s scanned by %s (%d)",
955 devid, btrfs_dev_name(device),
956 path, current->comm,
957 task_pid_nr(current));
958 }
959
960 name = rcu_string_strdup(path, GFP_NOFS);
961 if (!name) {
962 mutex_unlock(&fs_devices->device_list_mutex);
963 return ERR_PTR(-ENOMEM);
964 }
965 rcu_string_free(device->name);
966 rcu_assign_pointer(device->name, name);
967 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
968 fs_devices->missing_devices--;
969 clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
970 }
971 device->devt = path_devt;
972 }
973
974 /*
975 * Unmount does not free the btrfs_device struct but would zero
976 * generation along with most of the other members. So just update
977 * it back. We need it to pick the disk with largest generation
978 * (as above).
979 */
980 if (!fs_devices->opened) {
981 device->generation = found_transid;
982 fs_devices->latest_generation = max_t(u64, found_transid,
983 fs_devices->latest_generation);
984 }
985
986 fs_devices->total_devices = btrfs_super_num_devices(disk_super);
987
988 mutex_unlock(&fs_devices->device_list_mutex);
989 return device;
990 }
991
clone_fs_devices(struct btrfs_fs_devices * orig)992 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
993 {
994 struct btrfs_fs_devices *fs_devices;
995 struct btrfs_device *device;
996 struct btrfs_device *orig_dev;
997 int ret = 0;
998
999 lockdep_assert_held(&uuid_mutex);
1000
1001 fs_devices = alloc_fs_devices(orig->fsid);
1002 if (IS_ERR(fs_devices))
1003 return fs_devices;
1004
1005 fs_devices->total_devices = orig->total_devices;
1006
1007 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
1008 const char *dev_path = NULL;
1009
1010 /*
1011 * This is ok to do without RCU read locked because we hold the
1012 * uuid mutex so nothing we touch in here is going to disappear.
1013 */
1014 if (orig_dev->name)
1015 dev_path = orig_dev->name->str;
1016
1017 device = btrfs_alloc_device(NULL, &orig_dev->devid,
1018 orig_dev->uuid, dev_path);
1019 if (IS_ERR(device)) {
1020 ret = PTR_ERR(device);
1021 goto error;
1022 }
1023
1024 if (orig_dev->zone_info) {
1025 struct btrfs_zoned_device_info *zone_info;
1026
1027 zone_info = btrfs_clone_dev_zone_info(orig_dev);
1028 if (!zone_info) {
1029 btrfs_free_device(device);
1030 ret = -ENOMEM;
1031 goto error;
1032 }
1033 device->zone_info = zone_info;
1034 }
1035
1036 list_add(&device->dev_list, &fs_devices->devices);
1037 device->fs_devices = fs_devices;
1038 fs_devices->num_devices++;
1039 }
1040 return fs_devices;
1041 error:
1042 free_fs_devices(fs_devices);
1043 return ERR_PTR(ret);
1044 }
1045
__btrfs_free_extra_devids(struct btrfs_fs_devices * fs_devices,struct btrfs_device ** latest_dev)1046 static void __btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices,
1047 struct btrfs_device **latest_dev)
1048 {
1049 struct btrfs_device *device, *next;
1050
1051 /* This is the initialized path, it is safe to release the devices. */
1052 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
1053 if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state)) {
1054 if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT,
1055 &device->dev_state) &&
1056 !test_bit(BTRFS_DEV_STATE_MISSING,
1057 &device->dev_state) &&
1058 (!*latest_dev ||
1059 device->generation > (*latest_dev)->generation)) {
1060 *latest_dev = device;
1061 }
1062 continue;
1063 }
1064
1065 /*
1066 * We have already validated the presence of BTRFS_DEV_REPLACE_DEVID,
1067 * in btrfs_init_dev_replace() so just continue.
1068 */
1069 if (device->devid == BTRFS_DEV_REPLACE_DEVID)
1070 continue;
1071
1072 if (device->bdev_file) {
1073 fput(device->bdev_file);
1074 device->bdev = NULL;
1075 device->bdev_file = NULL;
1076 fs_devices->open_devices--;
1077 }
1078 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1079 list_del_init(&device->dev_alloc_list);
1080 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1081 fs_devices->rw_devices--;
1082 }
1083 list_del_init(&device->dev_list);
1084 fs_devices->num_devices--;
1085 btrfs_free_device(device);
1086 }
1087
1088 }
1089
1090 /*
1091 * After we have read the system tree and know devids belonging to this
1092 * filesystem, remove the device which does not belong there.
1093 */
btrfs_free_extra_devids(struct btrfs_fs_devices * fs_devices)1094 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices)
1095 {
1096 struct btrfs_device *latest_dev = NULL;
1097 struct btrfs_fs_devices *seed_dev;
1098
1099 mutex_lock(&uuid_mutex);
1100 __btrfs_free_extra_devids(fs_devices, &latest_dev);
1101
1102 list_for_each_entry(seed_dev, &fs_devices->seed_list, seed_list)
1103 __btrfs_free_extra_devids(seed_dev, &latest_dev);
1104
1105 fs_devices->latest_dev = latest_dev;
1106
1107 mutex_unlock(&uuid_mutex);
1108 }
1109
btrfs_close_bdev(struct btrfs_device * device)1110 static void btrfs_close_bdev(struct btrfs_device *device)
1111 {
1112 if (!device->bdev)
1113 return;
1114
1115 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1116 sync_blockdev(device->bdev);
1117 invalidate_bdev(device->bdev);
1118 }
1119
1120 fput(device->bdev_file);
1121 }
1122
btrfs_close_one_device(struct btrfs_device * device)1123 static void btrfs_close_one_device(struct btrfs_device *device)
1124 {
1125 struct btrfs_fs_devices *fs_devices = device->fs_devices;
1126
1127 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
1128 device->devid != BTRFS_DEV_REPLACE_DEVID) {
1129 list_del_init(&device->dev_alloc_list);
1130 fs_devices->rw_devices--;
1131 }
1132
1133 if (device->devid == BTRFS_DEV_REPLACE_DEVID)
1134 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
1135
1136 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
1137 clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
1138 fs_devices->missing_devices--;
1139 }
1140
1141 btrfs_close_bdev(device);
1142 if (device->bdev) {
1143 fs_devices->open_devices--;
1144 device->bdev = NULL;
1145 device->bdev_file = NULL;
1146 }
1147 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
1148 btrfs_destroy_dev_zone_info(device);
1149
1150 device->fs_info = NULL;
1151 atomic_set(&device->dev_stats_ccnt, 0);
1152 extent_io_tree_release(&device->alloc_state);
1153
1154 /*
1155 * Reset the flush error record. We might have a transient flush error
1156 * in this mount, and if so we aborted the current transaction and set
1157 * the fs to an error state, guaranteeing no super blocks can be further
1158 * committed. However that error might be transient and if we unmount the
1159 * filesystem and mount it again, we should allow the mount to succeed
1160 * (btrfs_check_rw_degradable() should not fail) - if after mounting the
1161 * filesystem again we still get flush errors, then we will again abort
1162 * any transaction and set the error state, guaranteeing no commits of
1163 * unsafe super blocks.
1164 */
1165 device->last_flush_error = 0;
1166
1167 /* Verify the device is back in a pristine state */
1168 WARN_ON(test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state));
1169 WARN_ON(test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state));
1170 WARN_ON(!list_empty(&device->dev_alloc_list));
1171 WARN_ON(!list_empty(&device->post_commit_list));
1172 }
1173
close_fs_devices(struct btrfs_fs_devices * fs_devices)1174 static void close_fs_devices(struct btrfs_fs_devices *fs_devices)
1175 {
1176 struct btrfs_device *device, *tmp;
1177
1178 lockdep_assert_held(&uuid_mutex);
1179
1180 if (--fs_devices->opened > 0)
1181 return;
1182
1183 list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list)
1184 btrfs_close_one_device(device);
1185
1186 WARN_ON(fs_devices->open_devices);
1187 WARN_ON(fs_devices->rw_devices);
1188 fs_devices->opened = 0;
1189 fs_devices->seeding = false;
1190 fs_devices->fs_info = NULL;
1191 }
1192
btrfs_close_devices(struct btrfs_fs_devices * fs_devices)1193 void btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
1194 {
1195 LIST_HEAD(list);
1196 struct btrfs_fs_devices *tmp;
1197
1198 mutex_lock(&uuid_mutex);
1199 close_fs_devices(fs_devices);
1200 if (!fs_devices->opened) {
1201 list_splice_init(&fs_devices->seed_list, &list);
1202
1203 /*
1204 * If the struct btrfs_fs_devices is not assembled with any
1205 * other device, it can be re-initialized during the next mount
1206 * without the needing device-scan step. Therefore, it can be
1207 * fully freed.
1208 */
1209 if (fs_devices->num_devices == 1) {
1210 list_del(&fs_devices->fs_list);
1211 free_fs_devices(fs_devices);
1212 }
1213 }
1214
1215
1216 list_for_each_entry_safe(fs_devices, tmp, &list, seed_list) {
1217 close_fs_devices(fs_devices);
1218 list_del(&fs_devices->seed_list);
1219 free_fs_devices(fs_devices);
1220 }
1221 mutex_unlock(&uuid_mutex);
1222 }
1223
open_fs_devices(struct btrfs_fs_devices * fs_devices,blk_mode_t flags,void * holder)1224 static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
1225 blk_mode_t flags, void *holder)
1226 {
1227 struct btrfs_device *device;
1228 struct btrfs_device *latest_dev = NULL;
1229 struct btrfs_device *tmp_device;
1230 s64 __maybe_unused value = 0;
1231 int ret = 0;
1232
1233 list_for_each_entry_safe(device, tmp_device, &fs_devices->devices,
1234 dev_list) {
1235 int ret2;
1236
1237 ret2 = btrfs_open_one_device(fs_devices, device, flags, holder);
1238 if (ret2 == 0 &&
1239 (!latest_dev || device->generation > latest_dev->generation)) {
1240 latest_dev = device;
1241 } else if (ret2 == -ENODATA) {
1242 fs_devices->num_devices--;
1243 list_del(&device->dev_list);
1244 btrfs_free_device(device);
1245 }
1246 if (ret == 0 && ret2 != 0)
1247 ret = ret2;
1248 }
1249
1250 if (fs_devices->open_devices == 0) {
1251 if (ret)
1252 return ret;
1253 return -EINVAL;
1254 }
1255
1256 fs_devices->opened = 1;
1257 fs_devices->latest_dev = latest_dev;
1258 fs_devices->total_rw_bytes = 0;
1259 fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_REGULAR;
1260 #ifdef CONFIG_BTRFS_EXPERIMENTAL
1261 fs_devices->rr_min_contig_read = BTRFS_DEFAULT_RR_MIN_CONTIG_READ;
1262 fs_devices->read_devid = latest_dev->devid;
1263 fs_devices->read_policy = btrfs_read_policy_to_enum(btrfs_get_mod_read_policy(),
1264 &value);
1265 if (fs_devices->read_policy == BTRFS_READ_POLICY_RR)
1266 fs_devices->collect_fs_stats = true;
1267
1268 if (value) {
1269 if (fs_devices->read_policy == BTRFS_READ_POLICY_RR)
1270 fs_devices->rr_min_contig_read = value;
1271 if (fs_devices->read_policy == BTRFS_READ_POLICY_DEVID)
1272 fs_devices->read_devid = value;
1273 }
1274 #else
1275 fs_devices->read_policy = BTRFS_READ_POLICY_PID;
1276 #endif
1277
1278 return 0;
1279 }
1280
devid_cmp(void * priv,const struct list_head * a,const struct list_head * b)1281 static int devid_cmp(void *priv, const struct list_head *a,
1282 const struct list_head *b)
1283 {
1284 const struct btrfs_device *dev1, *dev2;
1285
1286 dev1 = list_entry(a, struct btrfs_device, dev_list);
1287 dev2 = list_entry(b, struct btrfs_device, dev_list);
1288
1289 if (dev1->devid < dev2->devid)
1290 return -1;
1291 else if (dev1->devid > dev2->devid)
1292 return 1;
1293 return 0;
1294 }
1295
btrfs_open_devices(struct btrfs_fs_devices * fs_devices,blk_mode_t flags,void * holder)1296 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
1297 blk_mode_t flags, void *holder)
1298 {
1299 int ret;
1300
1301 lockdep_assert_held(&uuid_mutex);
1302 /*
1303 * The device_list_mutex cannot be taken here in case opening the
1304 * underlying device takes further locks like open_mutex.
1305 *
1306 * We also don't need the lock here as this is called during mount and
1307 * exclusion is provided by uuid_mutex
1308 */
1309
1310 if (fs_devices->opened) {
1311 fs_devices->opened++;
1312 ret = 0;
1313 } else {
1314 list_sort(NULL, &fs_devices->devices, devid_cmp);
1315 ret = open_fs_devices(fs_devices, flags, holder);
1316 }
1317
1318 return ret;
1319 }
1320
btrfs_release_disk_super(struct btrfs_super_block * super)1321 void btrfs_release_disk_super(struct btrfs_super_block *super)
1322 {
1323 struct page *page = virt_to_page(super);
1324
1325 put_page(page);
1326 }
1327
btrfs_read_disk_super(struct block_device * bdev,u64 bytenr,u64 bytenr_orig)1328 static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev,
1329 u64 bytenr, u64 bytenr_orig)
1330 {
1331 struct btrfs_super_block *disk_super;
1332 struct page *page;
1333 void *p;
1334 pgoff_t index;
1335
1336 /* make sure our super fits in the device */
1337 if (bytenr + PAGE_SIZE >= bdev_nr_bytes(bdev))
1338 return ERR_PTR(-EINVAL);
1339
1340 /* make sure our super fits in the page */
1341 if (sizeof(*disk_super) > PAGE_SIZE)
1342 return ERR_PTR(-EINVAL);
1343
1344 /* make sure our super doesn't straddle pages on disk */
1345 index = bytenr >> PAGE_SHIFT;
1346 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index)
1347 return ERR_PTR(-EINVAL);
1348
1349 /* pull in the page with our super */
1350 page = read_cache_page_gfp(bdev->bd_mapping, index, GFP_KERNEL);
1351
1352 if (IS_ERR(page))
1353 return ERR_CAST(page);
1354
1355 p = page_address(page);
1356
1357 /* align our pointer to the offset of the super block */
1358 disk_super = p + offset_in_page(bytenr);
1359
1360 if (btrfs_super_bytenr(disk_super) != bytenr_orig ||
1361 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1362 btrfs_release_disk_super(p);
1363 return ERR_PTR(-EINVAL);
1364 }
1365
1366 if (disk_super->label[0] && disk_super->label[BTRFS_LABEL_SIZE - 1])
1367 disk_super->label[BTRFS_LABEL_SIZE - 1] = 0;
1368
1369 return disk_super;
1370 }
1371
btrfs_forget_devices(dev_t devt)1372 int btrfs_forget_devices(dev_t devt)
1373 {
1374 int ret;
1375
1376 mutex_lock(&uuid_mutex);
1377 ret = btrfs_free_stale_devices(devt, NULL);
1378 mutex_unlock(&uuid_mutex);
1379
1380 return ret;
1381 }
1382
btrfs_skip_registration(struct btrfs_super_block * disk_super,const char * path,dev_t devt,bool mount_arg_dev)1383 static bool btrfs_skip_registration(struct btrfs_super_block *disk_super,
1384 const char *path, dev_t devt,
1385 bool mount_arg_dev)
1386 {
1387 struct btrfs_fs_devices *fs_devices;
1388
1389 /*
1390 * Do not skip device registration for mounted devices with matching
1391 * maj:min but different paths. Booting without initrd relies on
1392 * /dev/root initially, later replaced with the actual root device.
1393 * A successful scan ensures grub2-probe selects the correct device.
1394 */
1395 list_for_each_entry(fs_devices, &fs_uuids, fs_list) {
1396 struct btrfs_device *device;
1397
1398 mutex_lock(&fs_devices->device_list_mutex);
1399
1400 if (!fs_devices->opened) {
1401 mutex_unlock(&fs_devices->device_list_mutex);
1402 continue;
1403 }
1404
1405 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1406 if (device->bdev && (device->bdev->bd_dev == devt) &&
1407 strcmp(device->name->str, path) != 0) {
1408 mutex_unlock(&fs_devices->device_list_mutex);
1409
1410 /* Do not skip registration. */
1411 return false;
1412 }
1413 }
1414 mutex_unlock(&fs_devices->device_list_mutex);
1415 }
1416
1417 if (!mount_arg_dev && btrfs_super_num_devices(disk_super) == 1 &&
1418 !(btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING))
1419 return true;
1420
1421 return false;
1422 }
1423
1424 /*
1425 * Look for a btrfs signature on a device. This may be called out of the mount path
1426 * and we are not allowed to call set_blocksize during the scan. The superblock
1427 * is read via pagecache.
1428 *
1429 * With @mount_arg_dev it's a scan during mount time that will always register
1430 * the device or return an error. Multi-device and seeding devices are registered
1431 * in both cases.
1432 */
btrfs_scan_one_device(const char * path,blk_mode_t flags,bool mount_arg_dev)1433 struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags,
1434 bool mount_arg_dev)
1435 {
1436 struct btrfs_super_block *disk_super;
1437 bool new_device_added = false;
1438 struct btrfs_device *device = NULL;
1439 struct file *bdev_file;
1440 u64 bytenr;
1441 dev_t devt;
1442 int ret;
1443
1444 lockdep_assert_held(&uuid_mutex);
1445
1446 /*
1447 * Avoid an exclusive open here, as the systemd-udev may initiate the
1448 * device scan which may race with the user's mount or mkfs command,
1449 * resulting in failure.
1450 * Since the device scan is solely for reading purposes, there is no
1451 * need for an exclusive open. Additionally, the devices are read again
1452 * during the mount process. It is ok to get some inconsistent
1453 * values temporarily, as the device paths of the fsid are the only
1454 * required information for assembling the volume.
1455 */
1456 bdev_file = bdev_file_open_by_path(path, flags, NULL, NULL);
1457 if (IS_ERR(bdev_file))
1458 return ERR_CAST(bdev_file);
1459
1460 /*
1461 * We would like to check all the super blocks, but doing so would
1462 * allow a mount to succeed after a mkfs from a different filesystem.
1463 * Currently, recovery from a bad primary btrfs superblock is done
1464 * using the userspace command 'btrfs check --super'.
1465 */
1466 ret = btrfs_sb_log_location_bdev(file_bdev(bdev_file), 0, READ, &bytenr);
1467 if (ret) {
1468 device = ERR_PTR(ret);
1469 goto error_bdev_put;
1470 }
1471
1472 disk_super = btrfs_read_disk_super(file_bdev(bdev_file), bytenr,
1473 btrfs_sb_offset(0));
1474 if (IS_ERR(disk_super)) {
1475 device = ERR_CAST(disk_super);
1476 goto error_bdev_put;
1477 }
1478
1479 devt = file_bdev(bdev_file)->bd_dev;
1480 if (btrfs_skip_registration(disk_super, path, devt, mount_arg_dev)) {
1481 pr_debug("BTRFS: skip registering single non-seed device %s (%d:%d)\n",
1482 path, MAJOR(devt), MINOR(devt));
1483
1484 btrfs_free_stale_devices(devt, NULL);
1485
1486 device = NULL;
1487 goto free_disk_super;
1488 }
1489
1490 device = device_list_add(path, disk_super, &new_device_added);
1491 if (!IS_ERR(device) && new_device_added)
1492 btrfs_free_stale_devices(device->devt, device);
1493
1494 free_disk_super:
1495 btrfs_release_disk_super(disk_super);
1496
1497 error_bdev_put:
1498 fput(bdev_file);
1499
1500 return device;
1501 }
1502
1503 /*
1504 * Try to find a chunk that intersects [start, start + len] range and when one
1505 * such is found, record the end of it in *start
1506 */
contains_pending_extent(struct btrfs_device * device,u64 * start,u64 len)1507 static bool contains_pending_extent(struct btrfs_device *device, u64 *start,
1508 u64 len)
1509 {
1510 u64 physical_start, physical_end;
1511
1512 lockdep_assert_held(&device->fs_info->chunk_mutex);
1513
1514 if (find_first_extent_bit(&device->alloc_state, *start,
1515 &physical_start, &physical_end,
1516 CHUNK_ALLOCATED, NULL)) {
1517
1518 if (in_range(physical_start, *start, len) ||
1519 in_range(*start, physical_start,
1520 physical_end + 1 - physical_start)) {
1521 *start = physical_end + 1;
1522 return true;
1523 }
1524 }
1525 return false;
1526 }
1527
dev_extent_search_start(struct btrfs_device * device)1528 static u64 dev_extent_search_start(struct btrfs_device *device)
1529 {
1530 switch (device->fs_devices->chunk_alloc_policy) {
1531 case BTRFS_CHUNK_ALLOC_REGULAR:
1532 return BTRFS_DEVICE_RANGE_RESERVED;
1533 case BTRFS_CHUNK_ALLOC_ZONED:
1534 /*
1535 * We don't care about the starting region like regular
1536 * allocator, because we anyway use/reserve the first two zones
1537 * for superblock logging.
1538 */
1539 return 0;
1540 default:
1541 BUG();
1542 }
1543 }
1544
dev_extent_hole_check_zoned(struct btrfs_device * device,u64 * hole_start,u64 * hole_size,u64 num_bytes)1545 static bool dev_extent_hole_check_zoned(struct btrfs_device *device,
1546 u64 *hole_start, u64 *hole_size,
1547 u64 num_bytes)
1548 {
1549 u64 zone_size = device->zone_info->zone_size;
1550 u64 pos;
1551 int ret;
1552 bool changed = false;
1553
1554 ASSERT(IS_ALIGNED(*hole_start, zone_size));
1555
1556 while (*hole_size > 0) {
1557 pos = btrfs_find_allocatable_zones(device, *hole_start,
1558 *hole_start + *hole_size,
1559 num_bytes);
1560 if (pos != *hole_start) {
1561 *hole_size = *hole_start + *hole_size - pos;
1562 *hole_start = pos;
1563 changed = true;
1564 if (*hole_size < num_bytes)
1565 break;
1566 }
1567
1568 ret = btrfs_ensure_empty_zones(device, pos, num_bytes);
1569
1570 /* Range is ensured to be empty */
1571 if (!ret)
1572 return changed;
1573
1574 /* Given hole range was invalid (outside of device) */
1575 if (ret == -ERANGE) {
1576 *hole_start += *hole_size;
1577 *hole_size = 0;
1578 return true;
1579 }
1580
1581 *hole_start += zone_size;
1582 *hole_size -= zone_size;
1583 changed = true;
1584 }
1585
1586 return changed;
1587 }
1588
1589 /*
1590 * Check if specified hole is suitable for allocation.
1591 *
1592 * @device: the device which we have the hole
1593 * @hole_start: starting position of the hole
1594 * @hole_size: the size of the hole
1595 * @num_bytes: the size of the free space that we need
1596 *
1597 * This function may modify @hole_start and @hole_size to reflect the suitable
1598 * position for allocation. Returns 1 if hole position is updated, 0 otherwise.
1599 */
dev_extent_hole_check(struct btrfs_device * device,u64 * hole_start,u64 * hole_size,u64 num_bytes)1600 static bool dev_extent_hole_check(struct btrfs_device *device, u64 *hole_start,
1601 u64 *hole_size, u64 num_bytes)
1602 {
1603 bool changed = false;
1604 u64 hole_end = *hole_start + *hole_size;
1605
1606 for (;;) {
1607 /*
1608 * Check before we set max_hole_start, otherwise we could end up
1609 * sending back this offset anyway.
1610 */
1611 if (contains_pending_extent(device, hole_start, *hole_size)) {
1612 if (hole_end >= *hole_start)
1613 *hole_size = hole_end - *hole_start;
1614 else
1615 *hole_size = 0;
1616 changed = true;
1617 }
1618
1619 switch (device->fs_devices->chunk_alloc_policy) {
1620 case BTRFS_CHUNK_ALLOC_REGULAR:
1621 /* No extra check */
1622 break;
1623 case BTRFS_CHUNK_ALLOC_ZONED:
1624 if (dev_extent_hole_check_zoned(device, hole_start,
1625 hole_size, num_bytes)) {
1626 changed = true;
1627 /*
1628 * The changed hole can contain pending extent.
1629 * Loop again to check that.
1630 */
1631 continue;
1632 }
1633 break;
1634 default:
1635 BUG();
1636 }
1637
1638 break;
1639 }
1640
1641 return changed;
1642 }
1643
1644 /*
1645 * Find free space in the specified device.
1646 *
1647 * @device: the device which we search the free space in
1648 * @num_bytes: the size of the free space that we need
1649 * @search_start: the position from which to begin the search
1650 * @start: store the start of the free space.
1651 * @len: the size of the free space. that we find, or the size
1652 * of the max free space if we don't find suitable free space
1653 *
1654 * This does a pretty simple search, the expectation is that it is called very
1655 * infrequently and that a given device has a small number of extents.
1656 *
1657 * @start is used to store the start of the free space if we find. But if we
1658 * don't find suitable free space, it will be used to store the start position
1659 * of the max free space.
1660 *
1661 * @len is used to store the size of the free space that we find.
1662 * But if we don't find suitable free space, it is used to store the size of
1663 * the max free space.
1664 *
1665 * NOTE: This function will search *commit* root of device tree, and does extra
1666 * check to ensure dev extents are not double allocated.
1667 * This makes the function safe to allocate dev extents but may not report
1668 * correct usable device space, as device extent freed in current transaction
1669 * is not reported as available.
1670 */
find_free_dev_extent(struct btrfs_device * device,u64 num_bytes,u64 * start,u64 * len)1671 static int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
1672 u64 *start, u64 *len)
1673 {
1674 struct btrfs_fs_info *fs_info = device->fs_info;
1675 struct btrfs_root *root = fs_info->dev_root;
1676 struct btrfs_key key;
1677 struct btrfs_dev_extent *dev_extent;
1678 struct btrfs_path *path;
1679 u64 search_start;
1680 u64 hole_size;
1681 u64 max_hole_start;
1682 u64 max_hole_size = 0;
1683 u64 extent_end;
1684 u64 search_end = device->total_bytes;
1685 int ret;
1686 int slot;
1687 struct extent_buffer *l;
1688
1689 search_start = dev_extent_search_start(device);
1690 max_hole_start = search_start;
1691
1692 WARN_ON(device->zone_info &&
1693 !IS_ALIGNED(num_bytes, device->zone_info->zone_size));
1694
1695 path = btrfs_alloc_path();
1696 if (!path) {
1697 ret = -ENOMEM;
1698 goto out;
1699 }
1700 again:
1701 if (search_start >= search_end ||
1702 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1703 ret = -ENOSPC;
1704 goto out;
1705 }
1706
1707 path->reada = READA_FORWARD;
1708 path->search_commit_root = 1;
1709 path->skip_locking = 1;
1710
1711 key.objectid = device->devid;
1712 key.type = BTRFS_DEV_EXTENT_KEY;
1713 key.offset = search_start;
1714
1715 ret = btrfs_search_backwards(root, &key, path);
1716 if (ret < 0)
1717 goto out;
1718
1719 while (search_start < search_end) {
1720 l = path->nodes[0];
1721 slot = path->slots[0];
1722 if (slot >= btrfs_header_nritems(l)) {
1723 ret = btrfs_next_leaf(root, path);
1724 if (ret == 0)
1725 continue;
1726 if (ret < 0)
1727 goto out;
1728
1729 break;
1730 }
1731 btrfs_item_key_to_cpu(l, &key, slot);
1732
1733 if (key.objectid < device->devid)
1734 goto next;
1735
1736 if (key.objectid > device->devid)
1737 break;
1738
1739 if (key.type != BTRFS_DEV_EXTENT_KEY)
1740 goto next;
1741
1742 if (key.offset > search_end)
1743 break;
1744
1745 if (key.offset > search_start) {
1746 hole_size = key.offset - search_start;
1747 dev_extent_hole_check(device, &search_start, &hole_size,
1748 num_bytes);
1749
1750 if (hole_size > max_hole_size) {
1751 max_hole_start = search_start;
1752 max_hole_size = hole_size;
1753 }
1754
1755 /*
1756 * If this free space is greater than which we need,
1757 * it must be the max free space that we have found
1758 * until now, so max_hole_start must point to the start
1759 * of this free space and the length of this free space
1760 * is stored in max_hole_size. Thus, we return
1761 * max_hole_start and max_hole_size and go back to the
1762 * caller.
1763 */
1764 if (hole_size >= num_bytes) {
1765 ret = 0;
1766 goto out;
1767 }
1768 }
1769
1770 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1771 extent_end = key.offset + btrfs_dev_extent_length(l,
1772 dev_extent);
1773 if (extent_end > search_start)
1774 search_start = extent_end;
1775 next:
1776 path->slots[0]++;
1777 cond_resched();
1778 }
1779
1780 /*
1781 * At this point, search_start should be the end of
1782 * allocated dev extents, and when shrinking the device,
1783 * search_end may be smaller than search_start.
1784 */
1785 if (search_end > search_start) {
1786 hole_size = search_end - search_start;
1787 if (dev_extent_hole_check(device, &search_start, &hole_size,
1788 num_bytes)) {
1789 btrfs_release_path(path);
1790 goto again;
1791 }
1792
1793 if (hole_size > max_hole_size) {
1794 max_hole_start = search_start;
1795 max_hole_size = hole_size;
1796 }
1797 }
1798
1799 /* See above. */
1800 if (max_hole_size < num_bytes)
1801 ret = -ENOSPC;
1802 else
1803 ret = 0;
1804
1805 ASSERT(max_hole_start + max_hole_size <= search_end);
1806 out:
1807 btrfs_free_path(path);
1808 *start = max_hole_start;
1809 if (len)
1810 *len = max_hole_size;
1811 return ret;
1812 }
1813
btrfs_free_dev_extent(struct btrfs_trans_handle * trans,struct btrfs_device * device,u64 start,u64 * dev_extent_len)1814 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1815 struct btrfs_device *device,
1816 u64 start, u64 *dev_extent_len)
1817 {
1818 struct btrfs_fs_info *fs_info = device->fs_info;
1819 struct btrfs_root *root = fs_info->dev_root;
1820 int ret;
1821 struct btrfs_path *path;
1822 struct btrfs_key key;
1823 struct btrfs_key found_key;
1824 struct extent_buffer *leaf = NULL;
1825 struct btrfs_dev_extent *extent = NULL;
1826
1827 path = btrfs_alloc_path();
1828 if (!path)
1829 return -ENOMEM;
1830
1831 key.objectid = device->devid;
1832 key.type = BTRFS_DEV_EXTENT_KEY;
1833 key.offset = start;
1834 again:
1835 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1836 if (ret > 0) {
1837 ret = btrfs_previous_item(root, path, key.objectid,
1838 BTRFS_DEV_EXTENT_KEY);
1839 if (ret)
1840 goto out;
1841 leaf = path->nodes[0];
1842 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1843 extent = btrfs_item_ptr(leaf, path->slots[0],
1844 struct btrfs_dev_extent);
1845 BUG_ON(found_key.offset > start || found_key.offset +
1846 btrfs_dev_extent_length(leaf, extent) < start);
1847 key = found_key;
1848 btrfs_release_path(path);
1849 goto again;
1850 } else if (ret == 0) {
1851 leaf = path->nodes[0];
1852 extent = btrfs_item_ptr(leaf, path->slots[0],
1853 struct btrfs_dev_extent);
1854 } else {
1855 goto out;
1856 }
1857
1858 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1859
1860 ret = btrfs_del_item(trans, root, path);
1861 if (ret == 0)
1862 set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
1863 out:
1864 btrfs_free_path(path);
1865 return ret;
1866 }
1867
find_next_chunk(struct btrfs_fs_info * fs_info)1868 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1869 {
1870 struct rb_node *n;
1871 u64 ret = 0;
1872
1873 read_lock(&fs_info->mapping_tree_lock);
1874 n = rb_last(&fs_info->mapping_tree.rb_root);
1875 if (n) {
1876 struct btrfs_chunk_map *map;
1877
1878 map = rb_entry(n, struct btrfs_chunk_map, rb_node);
1879 ret = map->start + map->chunk_len;
1880 }
1881 read_unlock(&fs_info->mapping_tree_lock);
1882
1883 return ret;
1884 }
1885
find_next_devid(struct btrfs_fs_info * fs_info,u64 * devid_ret)1886 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1887 u64 *devid_ret)
1888 {
1889 int ret;
1890 struct btrfs_key key;
1891 struct btrfs_key found_key;
1892 struct btrfs_path *path;
1893
1894 path = btrfs_alloc_path();
1895 if (!path)
1896 return -ENOMEM;
1897
1898 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1899 key.type = BTRFS_DEV_ITEM_KEY;
1900 key.offset = (u64)-1;
1901
1902 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1903 if (ret < 0)
1904 goto error;
1905
1906 if (ret == 0) {
1907 /* Corruption */
1908 btrfs_err(fs_info, "corrupted chunk tree devid -1 matched");
1909 ret = -EUCLEAN;
1910 goto error;
1911 }
1912
1913 ret = btrfs_previous_item(fs_info->chunk_root, path,
1914 BTRFS_DEV_ITEMS_OBJECTID,
1915 BTRFS_DEV_ITEM_KEY);
1916 if (ret) {
1917 *devid_ret = 1;
1918 } else {
1919 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1920 path->slots[0]);
1921 *devid_ret = found_key.offset + 1;
1922 }
1923 ret = 0;
1924 error:
1925 btrfs_free_path(path);
1926 return ret;
1927 }
1928
1929 /*
1930 * the device information is stored in the chunk root
1931 * the btrfs_device struct should be fully filled in
1932 */
btrfs_add_dev_item(struct btrfs_trans_handle * trans,struct btrfs_device * device)1933 static int btrfs_add_dev_item(struct btrfs_trans_handle *trans,
1934 struct btrfs_device *device)
1935 {
1936 int ret;
1937 struct btrfs_path *path;
1938 struct btrfs_dev_item *dev_item;
1939 struct extent_buffer *leaf;
1940 struct btrfs_key key;
1941 unsigned long ptr;
1942
1943 path = btrfs_alloc_path();
1944 if (!path)
1945 return -ENOMEM;
1946
1947 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1948 key.type = BTRFS_DEV_ITEM_KEY;
1949 key.offset = device->devid;
1950
1951 btrfs_reserve_chunk_metadata(trans, true);
1952 ret = btrfs_insert_empty_item(trans, trans->fs_info->chunk_root, path,
1953 &key, sizeof(*dev_item));
1954 btrfs_trans_release_chunk_metadata(trans);
1955 if (ret)
1956 goto out;
1957
1958 leaf = path->nodes[0];
1959 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1960
1961 btrfs_set_device_id(leaf, dev_item, device->devid);
1962 btrfs_set_device_generation(leaf, dev_item, 0);
1963 btrfs_set_device_type(leaf, dev_item, device->type);
1964 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1965 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1966 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1967 btrfs_set_device_total_bytes(leaf, dev_item,
1968 btrfs_device_get_disk_total_bytes(device));
1969 btrfs_set_device_bytes_used(leaf, dev_item,
1970 btrfs_device_get_bytes_used(device));
1971 btrfs_set_device_group(leaf, dev_item, 0);
1972 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1973 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1974 btrfs_set_device_start_offset(leaf, dev_item, 0);
1975
1976 ptr = btrfs_device_uuid(dev_item);
1977 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1978 ptr = btrfs_device_fsid(dev_item);
1979 write_extent_buffer(leaf, trans->fs_info->fs_devices->metadata_uuid,
1980 ptr, BTRFS_FSID_SIZE);
1981
1982 ret = 0;
1983 out:
1984 btrfs_free_path(path);
1985 return ret;
1986 }
1987
1988 /*
1989 * Function to update ctime/mtime for a given device path.
1990 * Mainly used for ctime/mtime based probe like libblkid.
1991 *
1992 * We don't care about errors here, this is just to be kind to userspace.
1993 */
update_dev_time(const char * device_path)1994 static void update_dev_time(const char *device_path)
1995 {
1996 struct path path;
1997 int ret;
1998
1999 ret = kern_path(device_path, LOOKUP_FOLLOW, &path);
2000 if (ret)
2001 return;
2002
2003 inode_update_time(d_inode(path.dentry), S_MTIME | S_CTIME | S_VERSION);
2004 path_put(&path);
2005 }
2006
btrfs_rm_dev_item(struct btrfs_trans_handle * trans,struct btrfs_device * device)2007 static int btrfs_rm_dev_item(struct btrfs_trans_handle *trans,
2008 struct btrfs_device *device)
2009 {
2010 struct btrfs_root *root = device->fs_info->chunk_root;
2011 int ret;
2012 struct btrfs_path *path;
2013 struct btrfs_key key;
2014
2015 path = btrfs_alloc_path();
2016 if (!path)
2017 return -ENOMEM;
2018
2019 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2020 key.type = BTRFS_DEV_ITEM_KEY;
2021 key.offset = device->devid;
2022
2023 btrfs_reserve_chunk_metadata(trans, false);
2024 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2025 btrfs_trans_release_chunk_metadata(trans);
2026 if (ret) {
2027 if (ret > 0)
2028 ret = -ENOENT;
2029 goto out;
2030 }
2031
2032 ret = btrfs_del_item(trans, root, path);
2033 out:
2034 btrfs_free_path(path);
2035 return ret;
2036 }
2037
2038 /*
2039 * Verify that @num_devices satisfies the RAID profile constraints in the whole
2040 * filesystem. It's up to the caller to adjust that number regarding eg. device
2041 * replace.
2042 */
btrfs_check_raid_min_devices(struct btrfs_fs_info * fs_info,u64 num_devices)2043 static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
2044 u64 num_devices)
2045 {
2046 u64 all_avail;
2047 unsigned seq;
2048 int i;
2049
2050 do {
2051 seq = read_seqbegin(&fs_info->profiles_lock);
2052
2053 all_avail = fs_info->avail_data_alloc_bits |
2054 fs_info->avail_system_alloc_bits |
2055 fs_info->avail_metadata_alloc_bits;
2056 } while (read_seqretry(&fs_info->profiles_lock, seq));
2057
2058 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
2059 if (!(all_avail & btrfs_raid_array[i].bg_flag))
2060 continue;
2061
2062 if (num_devices < btrfs_raid_array[i].devs_min)
2063 return btrfs_raid_array[i].mindev_error;
2064 }
2065
2066 return 0;
2067 }
2068
btrfs_find_next_active_device(struct btrfs_fs_devices * fs_devs,struct btrfs_device * device)2069 static struct btrfs_device * btrfs_find_next_active_device(
2070 struct btrfs_fs_devices *fs_devs, struct btrfs_device *device)
2071 {
2072 struct btrfs_device *next_device;
2073
2074 list_for_each_entry(next_device, &fs_devs->devices, dev_list) {
2075 if (next_device != device &&
2076 !test_bit(BTRFS_DEV_STATE_MISSING, &next_device->dev_state)
2077 && next_device->bdev)
2078 return next_device;
2079 }
2080
2081 return NULL;
2082 }
2083
2084 /*
2085 * Helper function to check if the given device is part of s_bdev / latest_dev
2086 * and replace it with the provided or the next active device, in the context
2087 * where this function called, there should be always be another device (or
2088 * this_dev) which is active.
2089 */
btrfs_assign_next_active_device(struct btrfs_device * device,struct btrfs_device * next_device)2090 void __cold btrfs_assign_next_active_device(struct btrfs_device *device,
2091 struct btrfs_device *next_device)
2092 {
2093 struct btrfs_fs_info *fs_info = device->fs_info;
2094
2095 if (!next_device)
2096 next_device = btrfs_find_next_active_device(fs_info->fs_devices,
2097 device);
2098 ASSERT(next_device);
2099
2100 if (fs_info->sb->s_bdev &&
2101 (fs_info->sb->s_bdev == device->bdev))
2102 fs_info->sb->s_bdev = next_device->bdev;
2103
2104 if (fs_info->fs_devices->latest_dev->bdev == device->bdev)
2105 fs_info->fs_devices->latest_dev = next_device;
2106 }
2107
2108 /*
2109 * Return btrfs_fs_devices::num_devices excluding the device that's being
2110 * currently replaced.
2111 */
btrfs_num_devices(struct btrfs_fs_info * fs_info)2112 static u64 btrfs_num_devices(struct btrfs_fs_info *fs_info)
2113 {
2114 u64 num_devices = fs_info->fs_devices->num_devices;
2115
2116 down_read(&fs_info->dev_replace.rwsem);
2117 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
2118 ASSERT(num_devices > 1);
2119 num_devices--;
2120 }
2121 up_read(&fs_info->dev_replace.rwsem);
2122
2123 return num_devices;
2124 }
2125
btrfs_scratch_superblock(struct btrfs_fs_info * fs_info,struct block_device * bdev,int copy_num)2126 static void btrfs_scratch_superblock(struct btrfs_fs_info *fs_info,
2127 struct block_device *bdev, int copy_num)
2128 {
2129 struct btrfs_super_block *disk_super;
2130 const size_t len = sizeof(disk_super->magic);
2131 const u64 bytenr = btrfs_sb_offset(copy_num);
2132 int ret;
2133
2134 disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr);
2135 if (IS_ERR(disk_super))
2136 return;
2137
2138 memset(&disk_super->magic, 0, len);
2139 folio_mark_dirty(virt_to_folio(disk_super));
2140 btrfs_release_disk_super(disk_super);
2141
2142 ret = sync_blockdev_range(bdev, bytenr, bytenr + len - 1);
2143 if (ret)
2144 btrfs_warn(fs_info, "error clearing superblock number %d (%d)",
2145 copy_num, ret);
2146 }
2147
btrfs_scratch_superblocks(struct btrfs_fs_info * fs_info,struct btrfs_device * device)2148 void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, struct btrfs_device *device)
2149 {
2150 int copy_num;
2151 struct block_device *bdev = device->bdev;
2152
2153 if (!bdev)
2154 return;
2155
2156 for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX; copy_num++) {
2157 if (bdev_is_zoned(bdev))
2158 btrfs_reset_sb_log_zones(bdev, copy_num);
2159 else
2160 btrfs_scratch_superblock(fs_info, bdev, copy_num);
2161 }
2162
2163 /* Notify udev that device has changed */
2164 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
2165
2166 /* Update ctime/mtime for device path for libblkid */
2167 update_dev_time(device->name->str);
2168 }
2169
btrfs_rm_device(struct btrfs_fs_info * fs_info,struct btrfs_dev_lookup_args * args,struct file ** bdev_file)2170 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
2171 struct btrfs_dev_lookup_args *args,
2172 struct file **bdev_file)
2173 {
2174 struct btrfs_trans_handle *trans;
2175 struct btrfs_device *device;
2176 struct btrfs_fs_devices *cur_devices;
2177 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2178 u64 num_devices;
2179 int ret = 0;
2180
2181 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
2182 btrfs_err(fs_info, "device remove not supported on extent tree v2 yet");
2183 return -EINVAL;
2184 }
2185
2186 /*
2187 * The device list in fs_devices is accessed without locks (neither
2188 * uuid_mutex nor device_list_mutex) as it won't change on a mounted
2189 * filesystem and another device rm cannot run.
2190 */
2191 num_devices = btrfs_num_devices(fs_info);
2192
2193 ret = btrfs_check_raid_min_devices(fs_info, num_devices - 1);
2194 if (ret)
2195 return ret;
2196
2197 device = btrfs_find_device(fs_info->fs_devices, args);
2198 if (!device) {
2199 if (args->missing)
2200 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
2201 else
2202 ret = -ENOENT;
2203 return ret;
2204 }
2205
2206 if (btrfs_pinned_by_swapfile(fs_info, device)) {
2207 btrfs_warn_in_rcu(fs_info,
2208 "cannot remove device %s (devid %llu) due to active swapfile",
2209 btrfs_dev_name(device), device->devid);
2210 return -ETXTBSY;
2211 }
2212
2213 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
2214 return BTRFS_ERROR_DEV_TGT_REPLACE;
2215
2216 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
2217 fs_info->fs_devices->rw_devices == 1)
2218 return BTRFS_ERROR_DEV_ONLY_WRITABLE;
2219
2220 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
2221 mutex_lock(&fs_info->chunk_mutex);
2222 list_del_init(&device->dev_alloc_list);
2223 device->fs_devices->rw_devices--;
2224 mutex_unlock(&fs_info->chunk_mutex);
2225 }
2226
2227 ret = btrfs_shrink_device(device, 0);
2228 if (ret)
2229 goto error_undo;
2230
2231 trans = btrfs_start_transaction(fs_info->chunk_root, 0);
2232 if (IS_ERR(trans)) {
2233 ret = PTR_ERR(trans);
2234 goto error_undo;
2235 }
2236
2237 ret = btrfs_rm_dev_item(trans, device);
2238 if (ret) {
2239 /* Any error in dev item removal is critical */
2240 btrfs_crit(fs_info,
2241 "failed to remove device item for devid %llu: %d",
2242 device->devid, ret);
2243 btrfs_abort_transaction(trans, ret);
2244 btrfs_end_transaction(trans);
2245 return ret;
2246 }
2247
2248 clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
2249 btrfs_scrub_cancel_dev(device);
2250
2251 /*
2252 * the device list mutex makes sure that we don't change
2253 * the device list while someone else is writing out all
2254 * the device supers. Whoever is writing all supers, should
2255 * lock the device list mutex before getting the number of
2256 * devices in the super block (super_copy). Conversely,
2257 * whoever updates the number of devices in the super block
2258 * (super_copy) should hold the device list mutex.
2259 */
2260
2261 /*
2262 * In normal cases the cur_devices == fs_devices. But in case
2263 * of deleting a seed device, the cur_devices should point to
2264 * its own fs_devices listed under the fs_devices->seed_list.
2265 */
2266 cur_devices = device->fs_devices;
2267 mutex_lock(&fs_devices->device_list_mutex);
2268 list_del_rcu(&device->dev_list);
2269
2270 cur_devices->num_devices--;
2271 cur_devices->total_devices--;
2272 /* Update total_devices of the parent fs_devices if it's seed */
2273 if (cur_devices != fs_devices)
2274 fs_devices->total_devices--;
2275
2276 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state))
2277 cur_devices->missing_devices--;
2278
2279 btrfs_assign_next_active_device(device, NULL);
2280
2281 if (device->bdev_file) {
2282 cur_devices->open_devices--;
2283 /* remove sysfs entry */
2284 btrfs_sysfs_remove_device(device);
2285 }
2286
2287 num_devices = btrfs_super_num_devices(fs_info->super_copy) - 1;
2288 btrfs_set_super_num_devices(fs_info->super_copy, num_devices);
2289 mutex_unlock(&fs_devices->device_list_mutex);
2290
2291 /*
2292 * At this point, the device is zero sized and detached from the
2293 * devices list. All that's left is to zero out the old supers and
2294 * free the device.
2295 *
2296 * We cannot call btrfs_close_bdev() here because we're holding the sb
2297 * write lock, and fput() on the block device will pull in the
2298 * ->open_mutex on the block device and it's dependencies. Instead
2299 * just flush the device and let the caller do the final bdev_release.
2300 */
2301 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
2302 btrfs_scratch_superblocks(fs_info, device);
2303 if (device->bdev) {
2304 sync_blockdev(device->bdev);
2305 invalidate_bdev(device->bdev);
2306 }
2307 }
2308
2309 *bdev_file = device->bdev_file;
2310 synchronize_rcu();
2311 btrfs_free_device(device);
2312
2313 /*
2314 * This can happen if cur_devices is the private seed devices list. We
2315 * cannot call close_fs_devices() here because it expects the uuid_mutex
2316 * to be held, but in fact we don't need that for the private
2317 * seed_devices, we can simply decrement cur_devices->opened and then
2318 * remove it from our list and free the fs_devices.
2319 */
2320 if (cur_devices->num_devices == 0) {
2321 list_del_init(&cur_devices->seed_list);
2322 ASSERT(cur_devices->opened == 1);
2323 cur_devices->opened--;
2324 free_fs_devices(cur_devices);
2325 }
2326
2327 ret = btrfs_commit_transaction(trans);
2328
2329 return ret;
2330
2331 error_undo:
2332 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
2333 mutex_lock(&fs_info->chunk_mutex);
2334 list_add(&device->dev_alloc_list,
2335 &fs_devices->alloc_list);
2336 device->fs_devices->rw_devices++;
2337 mutex_unlock(&fs_info->chunk_mutex);
2338 }
2339 return ret;
2340 }
2341
btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device * srcdev)2342 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev)
2343 {
2344 struct btrfs_fs_devices *fs_devices;
2345
2346 lockdep_assert_held(&srcdev->fs_info->fs_devices->device_list_mutex);
2347
2348 /*
2349 * in case of fs with no seed, srcdev->fs_devices will point
2350 * to fs_devices of fs_info. However when the dev being replaced is
2351 * a seed dev it will point to the seed's local fs_devices. In short
2352 * srcdev will have its correct fs_devices in both the cases.
2353 */
2354 fs_devices = srcdev->fs_devices;
2355
2356 list_del_rcu(&srcdev->dev_list);
2357 list_del(&srcdev->dev_alloc_list);
2358 fs_devices->num_devices--;
2359 if (test_bit(BTRFS_DEV_STATE_MISSING, &srcdev->dev_state))
2360 fs_devices->missing_devices--;
2361
2362 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state))
2363 fs_devices->rw_devices--;
2364
2365 if (srcdev->bdev)
2366 fs_devices->open_devices--;
2367 }
2368
btrfs_rm_dev_replace_free_srcdev(struct btrfs_device * srcdev)2369 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev)
2370 {
2371 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
2372
2373 mutex_lock(&uuid_mutex);
2374
2375 btrfs_close_bdev(srcdev);
2376 synchronize_rcu();
2377 btrfs_free_device(srcdev);
2378
2379 /* if this is no devs we rather delete the fs_devices */
2380 if (!fs_devices->num_devices) {
2381 /*
2382 * On a mounted FS, num_devices can't be zero unless it's a
2383 * seed. In case of a seed device being replaced, the replace
2384 * target added to the sprout FS, so there will be no more
2385 * device left under the seed FS.
2386 */
2387 ASSERT(fs_devices->seeding);
2388
2389 list_del_init(&fs_devices->seed_list);
2390 close_fs_devices(fs_devices);
2391 free_fs_devices(fs_devices);
2392 }
2393 mutex_unlock(&uuid_mutex);
2394 }
2395
btrfs_destroy_dev_replace_tgtdev(struct btrfs_device * tgtdev)2396 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev)
2397 {
2398 struct btrfs_fs_devices *fs_devices = tgtdev->fs_info->fs_devices;
2399
2400 mutex_lock(&fs_devices->device_list_mutex);
2401
2402 btrfs_sysfs_remove_device(tgtdev);
2403
2404 if (tgtdev->bdev)
2405 fs_devices->open_devices--;
2406
2407 fs_devices->num_devices--;
2408
2409 btrfs_assign_next_active_device(tgtdev, NULL);
2410
2411 list_del_rcu(&tgtdev->dev_list);
2412
2413 mutex_unlock(&fs_devices->device_list_mutex);
2414
2415 btrfs_scratch_superblocks(tgtdev->fs_info, tgtdev);
2416
2417 btrfs_close_bdev(tgtdev);
2418 synchronize_rcu();
2419 btrfs_free_device(tgtdev);
2420 }
2421
2422 /*
2423 * Populate args from device at path.
2424 *
2425 * @fs_info: the filesystem
2426 * @args: the args to populate
2427 * @path: the path to the device
2428 *
2429 * This will read the super block of the device at @path and populate @args with
2430 * the devid, fsid, and uuid. This is meant to be used for ioctls that need to
2431 * lookup a device to operate on, but need to do it before we take any locks.
2432 * This properly handles the special case of "missing" that a user may pass in,
2433 * and does some basic sanity checks. The caller must make sure that @path is
2434 * properly NUL terminated before calling in, and must call
2435 * btrfs_put_dev_args_from_path() in order to free up the temporary fsid and
2436 * uuid buffers.
2437 *
2438 * Return: 0 for success, -errno for failure
2439 */
btrfs_get_dev_args_from_path(struct btrfs_fs_info * fs_info,struct btrfs_dev_lookup_args * args,const char * path)2440 int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
2441 struct btrfs_dev_lookup_args *args,
2442 const char *path)
2443 {
2444 struct btrfs_super_block *disk_super;
2445 struct file *bdev_file;
2446 int ret;
2447
2448 if (!path || !path[0])
2449 return -EINVAL;
2450 if (!strcmp(path, "missing")) {
2451 args->missing = true;
2452 return 0;
2453 }
2454
2455 args->uuid = kzalloc(BTRFS_UUID_SIZE, GFP_KERNEL);
2456 args->fsid = kzalloc(BTRFS_FSID_SIZE, GFP_KERNEL);
2457 if (!args->uuid || !args->fsid) {
2458 btrfs_put_dev_args_from_path(args);
2459 return -ENOMEM;
2460 }
2461
2462 ret = btrfs_get_bdev_and_sb(path, BLK_OPEN_READ, NULL, 0,
2463 &bdev_file, &disk_super);
2464 if (ret) {
2465 btrfs_put_dev_args_from_path(args);
2466 return ret;
2467 }
2468
2469 args->devid = btrfs_stack_device_id(&disk_super->dev_item);
2470 memcpy(args->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE);
2471 if (btrfs_fs_incompat(fs_info, METADATA_UUID))
2472 memcpy(args->fsid, disk_super->metadata_uuid, BTRFS_FSID_SIZE);
2473 else
2474 memcpy(args->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
2475 btrfs_release_disk_super(disk_super);
2476 fput(bdev_file);
2477 return 0;
2478 }
2479
2480 /*
2481 * Only use this jointly with btrfs_get_dev_args_from_path() because we will
2482 * allocate our ->uuid and ->fsid pointers, everybody else uses local variables
2483 * that don't need to be freed.
2484 */
btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args * args)2485 void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args)
2486 {
2487 kfree(args->uuid);
2488 kfree(args->fsid);
2489 args->uuid = NULL;
2490 args->fsid = NULL;
2491 }
2492
btrfs_find_device_by_devspec(struct btrfs_fs_info * fs_info,u64 devid,const char * device_path)2493 struct btrfs_device *btrfs_find_device_by_devspec(
2494 struct btrfs_fs_info *fs_info, u64 devid,
2495 const char *device_path)
2496 {
2497 BTRFS_DEV_LOOKUP_ARGS(args);
2498 struct btrfs_device *device;
2499 int ret;
2500
2501 if (devid) {
2502 args.devid = devid;
2503 device = btrfs_find_device(fs_info->fs_devices, &args);
2504 if (!device)
2505 return ERR_PTR(-ENOENT);
2506 return device;
2507 }
2508
2509 ret = btrfs_get_dev_args_from_path(fs_info, &args, device_path);
2510 if (ret)
2511 return ERR_PTR(ret);
2512 device = btrfs_find_device(fs_info->fs_devices, &args);
2513 btrfs_put_dev_args_from_path(&args);
2514 if (!device)
2515 return ERR_PTR(-ENOENT);
2516 return device;
2517 }
2518
btrfs_init_sprout(struct btrfs_fs_info * fs_info)2519 static struct btrfs_fs_devices *btrfs_init_sprout(struct btrfs_fs_info *fs_info)
2520 {
2521 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2522 struct btrfs_fs_devices *old_devices;
2523 struct btrfs_fs_devices *seed_devices;
2524
2525 lockdep_assert_held(&uuid_mutex);
2526 if (!fs_devices->seeding)
2527 return ERR_PTR(-EINVAL);
2528
2529 /*
2530 * Private copy of the seed devices, anchored at
2531 * fs_info->fs_devices->seed_list
2532 */
2533 seed_devices = alloc_fs_devices(NULL);
2534 if (IS_ERR(seed_devices))
2535 return seed_devices;
2536
2537 /*
2538 * It's necessary to retain a copy of the original seed fs_devices in
2539 * fs_uuids so that filesystems which have been seeded can successfully
2540 * reference the seed device from open_seed_devices. This also supports
2541 * multiple fs seed.
2542 */
2543 old_devices = clone_fs_devices(fs_devices);
2544 if (IS_ERR(old_devices)) {
2545 kfree(seed_devices);
2546 return old_devices;
2547 }
2548
2549 list_add(&old_devices->fs_list, &fs_uuids);
2550
2551 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
2552 seed_devices->opened = 1;
2553 INIT_LIST_HEAD(&seed_devices->devices);
2554 INIT_LIST_HEAD(&seed_devices->alloc_list);
2555 mutex_init(&seed_devices->device_list_mutex);
2556
2557 return seed_devices;
2558 }
2559
2560 /*
2561 * Splice seed devices into the sprout fs_devices.
2562 * Generate a new fsid for the sprouted read-write filesystem.
2563 */
btrfs_setup_sprout(struct btrfs_fs_info * fs_info,struct btrfs_fs_devices * seed_devices)2564 static void btrfs_setup_sprout(struct btrfs_fs_info *fs_info,
2565 struct btrfs_fs_devices *seed_devices)
2566 {
2567 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2568 struct btrfs_super_block *disk_super = fs_info->super_copy;
2569 struct btrfs_device *device;
2570 u64 super_flags;
2571
2572 /*
2573 * We are updating the fsid, the thread leading to device_list_add()
2574 * could race, so uuid_mutex is needed.
2575 */
2576 lockdep_assert_held(&uuid_mutex);
2577
2578 /*
2579 * The threads listed below may traverse dev_list but can do that without
2580 * device_list_mutex:
2581 * - All device ops and balance - as we are in btrfs_exclop_start.
2582 * - Various dev_list readers - are using RCU.
2583 * - btrfs_ioctl_fitrim() - is using RCU.
2584 *
2585 * For-read threads as below are using device_list_mutex:
2586 * - Readonly scrub btrfs_scrub_dev()
2587 * - Readonly scrub btrfs_scrub_progress()
2588 * - btrfs_get_dev_stats()
2589 */
2590 lockdep_assert_held(&fs_devices->device_list_mutex);
2591
2592 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
2593 synchronize_rcu);
2594 list_for_each_entry(device, &seed_devices->devices, dev_list)
2595 device->fs_devices = seed_devices;
2596
2597 fs_devices->seeding = false;
2598 fs_devices->num_devices = 0;
2599 fs_devices->open_devices = 0;
2600 fs_devices->missing_devices = 0;
2601 fs_devices->rotating = false;
2602 list_add(&seed_devices->seed_list, &fs_devices->seed_list);
2603
2604 generate_random_uuid(fs_devices->fsid);
2605 memcpy(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE);
2606 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2607
2608 super_flags = btrfs_super_flags(disk_super) &
2609 ~BTRFS_SUPER_FLAG_SEEDING;
2610 btrfs_set_super_flags(disk_super, super_flags);
2611 }
2612
2613 /*
2614 * Store the expected generation for seed devices in device items.
2615 */
btrfs_finish_sprout(struct btrfs_trans_handle * trans)2616 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
2617 {
2618 BTRFS_DEV_LOOKUP_ARGS(args);
2619 struct btrfs_fs_info *fs_info = trans->fs_info;
2620 struct btrfs_root *root = fs_info->chunk_root;
2621 struct btrfs_path *path;
2622 struct extent_buffer *leaf;
2623 struct btrfs_dev_item *dev_item;
2624 struct btrfs_device *device;
2625 struct btrfs_key key;
2626 u8 fs_uuid[BTRFS_FSID_SIZE];
2627 u8 dev_uuid[BTRFS_UUID_SIZE];
2628 int ret;
2629
2630 path = btrfs_alloc_path();
2631 if (!path)
2632 return -ENOMEM;
2633
2634 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2635 key.type = BTRFS_DEV_ITEM_KEY;
2636 key.offset = 0;
2637
2638 while (1) {
2639 btrfs_reserve_chunk_metadata(trans, false);
2640 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2641 btrfs_trans_release_chunk_metadata(trans);
2642 if (ret < 0)
2643 goto error;
2644
2645 leaf = path->nodes[0];
2646 next_slot:
2647 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2648 ret = btrfs_next_leaf(root, path);
2649 if (ret > 0)
2650 break;
2651 if (ret < 0)
2652 goto error;
2653 leaf = path->nodes[0];
2654 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2655 btrfs_release_path(path);
2656 continue;
2657 }
2658
2659 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2660 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2661 key.type != BTRFS_DEV_ITEM_KEY)
2662 break;
2663
2664 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2665 struct btrfs_dev_item);
2666 args.devid = btrfs_device_id(leaf, dev_item);
2667 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2668 BTRFS_UUID_SIZE);
2669 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2670 BTRFS_FSID_SIZE);
2671 args.uuid = dev_uuid;
2672 args.fsid = fs_uuid;
2673 device = btrfs_find_device(fs_info->fs_devices, &args);
2674 BUG_ON(!device); /* Logic error */
2675
2676 if (device->fs_devices->seeding)
2677 btrfs_set_device_generation(leaf, dev_item,
2678 device->generation);
2679
2680 path->slots[0]++;
2681 goto next_slot;
2682 }
2683 ret = 0;
2684 error:
2685 btrfs_free_path(path);
2686 return ret;
2687 }
2688
btrfs_init_new_device(struct btrfs_fs_info * fs_info,const char * device_path)2689 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path)
2690 {
2691 struct btrfs_root *root = fs_info->dev_root;
2692 struct btrfs_trans_handle *trans;
2693 struct btrfs_device *device;
2694 struct file *bdev_file;
2695 struct super_block *sb = fs_info->sb;
2696 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2697 struct btrfs_fs_devices *seed_devices = NULL;
2698 u64 orig_super_total_bytes;
2699 u64 orig_super_num_devices;
2700 int ret = 0;
2701 bool seeding_dev = false;
2702 bool locked = false;
2703
2704 if (sb_rdonly(sb) && !fs_devices->seeding)
2705 return -EROFS;
2706
2707 bdev_file = bdev_file_open_by_path(device_path, BLK_OPEN_WRITE,
2708 fs_info->bdev_holder, NULL);
2709 if (IS_ERR(bdev_file))
2710 return PTR_ERR(bdev_file);
2711
2712 if (!btrfs_check_device_zone_type(fs_info, file_bdev(bdev_file))) {
2713 ret = -EINVAL;
2714 goto error;
2715 }
2716
2717 if (fs_devices->seeding) {
2718 seeding_dev = true;
2719 down_write(&sb->s_umount);
2720 mutex_lock(&uuid_mutex);
2721 locked = true;
2722 }
2723
2724 sync_blockdev(file_bdev(bdev_file));
2725
2726 rcu_read_lock();
2727 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
2728 if (device->bdev == file_bdev(bdev_file)) {
2729 ret = -EEXIST;
2730 rcu_read_unlock();
2731 goto error;
2732 }
2733 }
2734 rcu_read_unlock();
2735
2736 device = btrfs_alloc_device(fs_info, NULL, NULL, device_path);
2737 if (IS_ERR(device)) {
2738 /* we can safely leave the fs_devices entry around */
2739 ret = PTR_ERR(device);
2740 goto error;
2741 }
2742
2743 device->fs_info = fs_info;
2744 device->bdev_file = bdev_file;
2745 device->bdev = file_bdev(bdev_file);
2746 ret = lookup_bdev(device_path, &device->devt);
2747 if (ret)
2748 goto error_free_device;
2749
2750 ret = btrfs_get_dev_zone_info(device, false);
2751 if (ret)
2752 goto error_free_device;
2753
2754 trans = btrfs_start_transaction(root, 0);
2755 if (IS_ERR(trans)) {
2756 ret = PTR_ERR(trans);
2757 goto error_free_zone;
2758 }
2759
2760 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
2761 device->generation = trans->transid;
2762 device->io_width = fs_info->sectorsize;
2763 device->io_align = fs_info->sectorsize;
2764 device->sector_size = fs_info->sectorsize;
2765 device->total_bytes =
2766 round_down(bdev_nr_bytes(device->bdev), fs_info->sectorsize);
2767 device->disk_total_bytes = device->total_bytes;
2768 device->commit_total_bytes = device->total_bytes;
2769 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
2770 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
2771 device->dev_stats_valid = 1;
2772 set_blocksize(device->bdev_file, BTRFS_BDEV_BLOCKSIZE);
2773
2774 if (seeding_dev) {
2775 /* GFP_KERNEL allocation must not be under device_list_mutex */
2776 seed_devices = btrfs_init_sprout(fs_info);
2777 if (IS_ERR(seed_devices)) {
2778 ret = PTR_ERR(seed_devices);
2779 btrfs_abort_transaction(trans, ret);
2780 goto error_trans;
2781 }
2782 }
2783
2784 mutex_lock(&fs_devices->device_list_mutex);
2785 if (seeding_dev) {
2786 btrfs_setup_sprout(fs_info, seed_devices);
2787 btrfs_assign_next_active_device(fs_info->fs_devices->latest_dev,
2788 device);
2789 }
2790
2791 device->fs_devices = fs_devices;
2792
2793 mutex_lock(&fs_info->chunk_mutex);
2794 list_add_rcu(&device->dev_list, &fs_devices->devices);
2795 list_add(&device->dev_alloc_list, &fs_devices->alloc_list);
2796 fs_devices->num_devices++;
2797 fs_devices->open_devices++;
2798 fs_devices->rw_devices++;
2799 fs_devices->total_devices++;
2800 fs_devices->total_rw_bytes += device->total_bytes;
2801
2802 atomic64_add(device->total_bytes, &fs_info->free_chunk_space);
2803
2804 if (!bdev_nonrot(device->bdev))
2805 fs_devices->rotating = true;
2806
2807 orig_super_total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
2808 btrfs_set_super_total_bytes(fs_info->super_copy,
2809 round_down(orig_super_total_bytes + device->total_bytes,
2810 fs_info->sectorsize));
2811
2812 orig_super_num_devices = btrfs_super_num_devices(fs_info->super_copy);
2813 btrfs_set_super_num_devices(fs_info->super_copy,
2814 orig_super_num_devices + 1);
2815
2816 /*
2817 * we've got more storage, clear any full flags on the space
2818 * infos
2819 */
2820 btrfs_clear_space_info_full(fs_info);
2821
2822 mutex_unlock(&fs_info->chunk_mutex);
2823
2824 /* Add sysfs device entry */
2825 btrfs_sysfs_add_device(device);
2826
2827 mutex_unlock(&fs_devices->device_list_mutex);
2828
2829 if (seeding_dev) {
2830 mutex_lock(&fs_info->chunk_mutex);
2831 ret = init_first_rw_device(trans);
2832 mutex_unlock(&fs_info->chunk_mutex);
2833 if (ret) {
2834 btrfs_abort_transaction(trans, ret);
2835 goto error_sysfs;
2836 }
2837 }
2838
2839 ret = btrfs_add_dev_item(trans, device);
2840 if (ret) {
2841 btrfs_abort_transaction(trans, ret);
2842 goto error_sysfs;
2843 }
2844
2845 if (seeding_dev) {
2846 ret = btrfs_finish_sprout(trans);
2847 if (ret) {
2848 btrfs_abort_transaction(trans, ret);
2849 goto error_sysfs;
2850 }
2851
2852 /*
2853 * fs_devices now represents the newly sprouted filesystem and
2854 * its fsid has been changed by btrfs_sprout_splice().
2855 */
2856 btrfs_sysfs_update_sprout_fsid(fs_devices);
2857 }
2858
2859 ret = btrfs_commit_transaction(trans);
2860
2861 if (seeding_dev) {
2862 mutex_unlock(&uuid_mutex);
2863 up_write(&sb->s_umount);
2864 locked = false;
2865
2866 if (ret) /* transaction commit */
2867 return ret;
2868
2869 ret = btrfs_relocate_sys_chunks(fs_info);
2870 if (ret < 0)
2871 btrfs_handle_fs_error(fs_info, ret,
2872 "Failed to relocate sys chunks after device initialization. This can be fixed using the \"btrfs balance\" command.");
2873 trans = btrfs_attach_transaction(root);
2874 if (IS_ERR(trans)) {
2875 if (PTR_ERR(trans) == -ENOENT)
2876 return 0;
2877 ret = PTR_ERR(trans);
2878 trans = NULL;
2879 goto error_sysfs;
2880 }
2881 ret = btrfs_commit_transaction(trans);
2882 }
2883
2884 /*
2885 * Now that we have written a new super block to this device, check all
2886 * other fs_devices list if device_path alienates any other scanned
2887 * device.
2888 * We can ignore the return value as it typically returns -EINVAL and
2889 * only succeeds if the device was an alien.
2890 */
2891 btrfs_forget_devices(device->devt);
2892
2893 /* Update ctime/mtime for blkid or udev */
2894 update_dev_time(device_path);
2895
2896 return ret;
2897
2898 error_sysfs:
2899 btrfs_sysfs_remove_device(device);
2900 mutex_lock(&fs_info->fs_devices->device_list_mutex);
2901 mutex_lock(&fs_info->chunk_mutex);
2902 list_del_rcu(&device->dev_list);
2903 list_del(&device->dev_alloc_list);
2904 fs_info->fs_devices->num_devices--;
2905 fs_info->fs_devices->open_devices--;
2906 fs_info->fs_devices->rw_devices--;
2907 fs_info->fs_devices->total_devices--;
2908 fs_info->fs_devices->total_rw_bytes -= device->total_bytes;
2909 atomic64_sub(device->total_bytes, &fs_info->free_chunk_space);
2910 btrfs_set_super_total_bytes(fs_info->super_copy,
2911 orig_super_total_bytes);
2912 btrfs_set_super_num_devices(fs_info->super_copy,
2913 orig_super_num_devices);
2914 mutex_unlock(&fs_info->chunk_mutex);
2915 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2916 error_trans:
2917 if (trans)
2918 btrfs_end_transaction(trans);
2919 error_free_zone:
2920 btrfs_destroy_dev_zone_info(device);
2921 error_free_device:
2922 btrfs_free_device(device);
2923 error:
2924 fput(bdev_file);
2925 if (locked) {
2926 mutex_unlock(&uuid_mutex);
2927 up_write(&sb->s_umount);
2928 }
2929 return ret;
2930 }
2931
btrfs_update_device(struct btrfs_trans_handle * trans,struct btrfs_device * device)2932 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2933 struct btrfs_device *device)
2934 {
2935 int ret;
2936 struct btrfs_path *path;
2937 struct btrfs_root *root = device->fs_info->chunk_root;
2938 struct btrfs_dev_item *dev_item;
2939 struct extent_buffer *leaf;
2940 struct btrfs_key key;
2941
2942 path = btrfs_alloc_path();
2943 if (!path)
2944 return -ENOMEM;
2945
2946 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2947 key.type = BTRFS_DEV_ITEM_KEY;
2948 key.offset = device->devid;
2949
2950 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2951 if (ret < 0)
2952 goto out;
2953
2954 if (ret > 0) {
2955 ret = -ENOENT;
2956 goto out;
2957 }
2958
2959 leaf = path->nodes[0];
2960 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2961
2962 btrfs_set_device_id(leaf, dev_item, device->devid);
2963 btrfs_set_device_type(leaf, dev_item, device->type);
2964 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2965 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2966 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2967 btrfs_set_device_total_bytes(leaf, dev_item,
2968 btrfs_device_get_disk_total_bytes(device));
2969 btrfs_set_device_bytes_used(leaf, dev_item,
2970 btrfs_device_get_bytes_used(device));
2971 out:
2972 btrfs_free_path(path);
2973 return ret;
2974 }
2975
btrfs_grow_device(struct btrfs_trans_handle * trans,struct btrfs_device * device,u64 new_size)2976 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2977 struct btrfs_device *device, u64 new_size)
2978 {
2979 struct btrfs_fs_info *fs_info = device->fs_info;
2980 struct btrfs_super_block *super_copy = fs_info->super_copy;
2981 u64 old_total;
2982 u64 diff;
2983 int ret;
2984
2985 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state))
2986 return -EACCES;
2987
2988 new_size = round_down(new_size, fs_info->sectorsize);
2989
2990 mutex_lock(&fs_info->chunk_mutex);
2991 old_total = btrfs_super_total_bytes(super_copy);
2992 diff = round_down(new_size - device->total_bytes, fs_info->sectorsize);
2993
2994 if (new_size <= device->total_bytes ||
2995 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
2996 mutex_unlock(&fs_info->chunk_mutex);
2997 return -EINVAL;
2998 }
2999
3000 btrfs_set_super_total_bytes(super_copy,
3001 round_down(old_total + diff, fs_info->sectorsize));
3002 device->fs_devices->total_rw_bytes += diff;
3003 atomic64_add(diff, &fs_info->free_chunk_space);
3004
3005 btrfs_device_set_total_bytes(device, new_size);
3006 btrfs_device_set_disk_total_bytes(device, new_size);
3007 btrfs_clear_space_info_full(device->fs_info);
3008 if (list_empty(&device->post_commit_list))
3009 list_add_tail(&device->post_commit_list,
3010 &trans->transaction->dev_update_list);
3011 mutex_unlock(&fs_info->chunk_mutex);
3012
3013 btrfs_reserve_chunk_metadata(trans, false);
3014 ret = btrfs_update_device(trans, device);
3015 btrfs_trans_release_chunk_metadata(trans);
3016
3017 return ret;
3018 }
3019
btrfs_free_chunk(struct btrfs_trans_handle * trans,u64 chunk_offset)3020 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
3021 {
3022 struct btrfs_fs_info *fs_info = trans->fs_info;
3023 struct btrfs_root *root = fs_info->chunk_root;
3024 int ret;
3025 struct btrfs_path *path;
3026 struct btrfs_key key;
3027
3028 path = btrfs_alloc_path();
3029 if (!path)
3030 return -ENOMEM;
3031
3032 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3033 key.type = BTRFS_CHUNK_ITEM_KEY;
3034 key.offset = chunk_offset;
3035
3036 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3037 if (ret < 0)
3038 goto out;
3039 else if (ret > 0) { /* Logic error or corruption */
3040 btrfs_err(fs_info, "failed to lookup chunk %llu when freeing",
3041 chunk_offset);
3042 btrfs_abort_transaction(trans, -ENOENT);
3043 ret = -EUCLEAN;
3044 goto out;
3045 }
3046
3047 ret = btrfs_del_item(trans, root, path);
3048 if (ret < 0) {
3049 btrfs_err(fs_info, "failed to delete chunk %llu item", chunk_offset);
3050 btrfs_abort_transaction(trans, ret);
3051 goto out;
3052 }
3053 out:
3054 btrfs_free_path(path);
3055 return ret;
3056 }
3057
btrfs_del_sys_chunk(struct btrfs_fs_info * fs_info,u64 chunk_offset)3058 static int btrfs_del_sys_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
3059 {
3060 struct btrfs_super_block *super_copy = fs_info->super_copy;
3061 struct btrfs_disk_key *disk_key;
3062 struct btrfs_chunk *chunk;
3063 u8 *ptr;
3064 int ret = 0;
3065 u32 num_stripes;
3066 u32 array_size;
3067 u32 len = 0;
3068 u32 cur;
3069 struct btrfs_key key;
3070
3071 lockdep_assert_held(&fs_info->chunk_mutex);
3072 array_size = btrfs_super_sys_array_size(super_copy);
3073
3074 ptr = super_copy->sys_chunk_array;
3075 cur = 0;
3076
3077 while (cur < array_size) {
3078 disk_key = (struct btrfs_disk_key *)ptr;
3079 btrfs_disk_key_to_cpu(&key, disk_key);
3080
3081 len = sizeof(*disk_key);
3082
3083 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
3084 chunk = (struct btrfs_chunk *)(ptr + len);
3085 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
3086 len += btrfs_chunk_item_size(num_stripes);
3087 } else {
3088 ret = -EIO;
3089 break;
3090 }
3091 if (key.objectid == BTRFS_FIRST_CHUNK_TREE_OBJECTID &&
3092 key.offset == chunk_offset) {
3093 memmove(ptr, ptr + len, array_size - (cur + len));
3094 array_size -= len;
3095 btrfs_set_super_sys_array_size(super_copy, array_size);
3096 } else {
3097 ptr += len;
3098 cur += len;
3099 }
3100 }
3101 return ret;
3102 }
3103
btrfs_find_chunk_map_nolock(struct btrfs_fs_info * fs_info,u64 logical,u64 length)3104 struct btrfs_chunk_map *btrfs_find_chunk_map_nolock(struct btrfs_fs_info *fs_info,
3105 u64 logical, u64 length)
3106 {
3107 struct rb_node *node = fs_info->mapping_tree.rb_root.rb_node;
3108 struct rb_node *prev = NULL;
3109 struct rb_node *orig_prev;
3110 struct btrfs_chunk_map *map;
3111 struct btrfs_chunk_map *prev_map = NULL;
3112
3113 while (node) {
3114 map = rb_entry(node, struct btrfs_chunk_map, rb_node);
3115 prev = node;
3116 prev_map = map;
3117
3118 if (logical < map->start) {
3119 node = node->rb_left;
3120 } else if (logical >= map->start + map->chunk_len) {
3121 node = node->rb_right;
3122 } else {
3123 refcount_inc(&map->refs);
3124 return map;
3125 }
3126 }
3127
3128 if (!prev)
3129 return NULL;
3130
3131 orig_prev = prev;
3132 while (prev && logical >= prev_map->start + prev_map->chunk_len) {
3133 prev = rb_next(prev);
3134 prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
3135 }
3136
3137 if (!prev) {
3138 prev = orig_prev;
3139 prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
3140 while (prev && logical < prev_map->start) {
3141 prev = rb_prev(prev);
3142 prev_map = rb_entry(prev, struct btrfs_chunk_map, rb_node);
3143 }
3144 }
3145
3146 if (prev) {
3147 u64 end = logical + length;
3148
3149 /*
3150 * Caller can pass a U64_MAX length when it wants to get any
3151 * chunk starting at an offset of 'logical' or higher, so deal
3152 * with underflow by resetting the end offset to U64_MAX.
3153 */
3154 if (end < logical)
3155 end = U64_MAX;
3156
3157 if (end > prev_map->start &&
3158 logical < prev_map->start + prev_map->chunk_len) {
3159 refcount_inc(&prev_map->refs);
3160 return prev_map;
3161 }
3162 }
3163
3164 return NULL;
3165 }
3166
btrfs_find_chunk_map(struct btrfs_fs_info * fs_info,u64 logical,u64 length)3167 struct btrfs_chunk_map *btrfs_find_chunk_map(struct btrfs_fs_info *fs_info,
3168 u64 logical, u64 length)
3169 {
3170 struct btrfs_chunk_map *map;
3171
3172 read_lock(&fs_info->mapping_tree_lock);
3173 map = btrfs_find_chunk_map_nolock(fs_info, logical, length);
3174 read_unlock(&fs_info->mapping_tree_lock);
3175
3176 return map;
3177 }
3178
3179 /*
3180 * Find the mapping containing the given logical extent.
3181 *
3182 * @logical: Logical block offset in bytes.
3183 * @length: Length of extent in bytes.
3184 *
3185 * Return: Chunk mapping or ERR_PTR.
3186 */
btrfs_get_chunk_map(struct btrfs_fs_info * fs_info,u64 logical,u64 length)3187 struct btrfs_chunk_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info,
3188 u64 logical, u64 length)
3189 {
3190 struct btrfs_chunk_map *map;
3191
3192 map = btrfs_find_chunk_map(fs_info, logical, length);
3193
3194 if (unlikely(!map)) {
3195 btrfs_crit(fs_info,
3196 "unable to find chunk map for logical %llu length %llu",
3197 logical, length);
3198 return ERR_PTR(-EINVAL);
3199 }
3200
3201 if (unlikely(map->start > logical || map->start + map->chunk_len <= logical)) {
3202 btrfs_crit(fs_info,
3203 "found a bad chunk map, wanted %llu-%llu, found %llu-%llu",
3204 logical, logical + length, map->start,
3205 map->start + map->chunk_len);
3206 btrfs_free_chunk_map(map);
3207 return ERR_PTR(-EINVAL);
3208 }
3209
3210 /* Callers are responsible for dropping the reference. */
3211 return map;
3212 }
3213
remove_chunk_item(struct btrfs_trans_handle * trans,struct btrfs_chunk_map * map,u64 chunk_offset)3214 static int remove_chunk_item(struct btrfs_trans_handle *trans,
3215 struct btrfs_chunk_map *map, u64 chunk_offset)
3216 {
3217 int i;
3218
3219 /*
3220 * Removing chunk items and updating the device items in the chunks btree
3221 * requires holding the chunk_mutex.
3222 * See the comment at btrfs_chunk_alloc() for the details.
3223 */
3224 lockdep_assert_held(&trans->fs_info->chunk_mutex);
3225
3226 for (i = 0; i < map->num_stripes; i++) {
3227 int ret;
3228
3229 ret = btrfs_update_device(trans, map->stripes[i].dev);
3230 if (ret)
3231 return ret;
3232 }
3233
3234 return btrfs_free_chunk(trans, chunk_offset);
3235 }
3236
btrfs_remove_chunk(struct btrfs_trans_handle * trans,u64 chunk_offset)3237 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset)
3238 {
3239 struct btrfs_fs_info *fs_info = trans->fs_info;
3240 struct btrfs_chunk_map *map;
3241 u64 dev_extent_len = 0;
3242 int i, ret = 0;
3243 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3244
3245 map = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
3246 if (IS_ERR(map)) {
3247 /*
3248 * This is a logic error, but we don't want to just rely on the
3249 * user having built with ASSERT enabled, so if ASSERT doesn't
3250 * do anything we still error out.
3251 */
3252 ASSERT(0);
3253 return PTR_ERR(map);
3254 }
3255
3256 /*
3257 * First delete the device extent items from the devices btree.
3258 * We take the device_list_mutex to avoid racing with the finishing phase
3259 * of a device replace operation. See the comment below before acquiring
3260 * fs_info->chunk_mutex. Note that here we do not acquire the chunk_mutex
3261 * because that can result in a deadlock when deleting the device extent
3262 * items from the devices btree - COWing an extent buffer from the btree
3263 * may result in allocating a new metadata chunk, which would attempt to
3264 * lock again fs_info->chunk_mutex.
3265 */
3266 mutex_lock(&fs_devices->device_list_mutex);
3267 for (i = 0; i < map->num_stripes; i++) {
3268 struct btrfs_device *device = map->stripes[i].dev;
3269 ret = btrfs_free_dev_extent(trans, device,
3270 map->stripes[i].physical,
3271 &dev_extent_len);
3272 if (ret) {
3273 mutex_unlock(&fs_devices->device_list_mutex);
3274 btrfs_abort_transaction(trans, ret);
3275 goto out;
3276 }
3277
3278 if (device->bytes_used > 0) {
3279 mutex_lock(&fs_info->chunk_mutex);
3280 btrfs_device_set_bytes_used(device,
3281 device->bytes_used - dev_extent_len);
3282 atomic64_add(dev_extent_len, &fs_info->free_chunk_space);
3283 btrfs_clear_space_info_full(fs_info);
3284 mutex_unlock(&fs_info->chunk_mutex);
3285 }
3286 }
3287 mutex_unlock(&fs_devices->device_list_mutex);
3288
3289 /*
3290 * We acquire fs_info->chunk_mutex for 2 reasons:
3291 *
3292 * 1) Just like with the first phase of the chunk allocation, we must
3293 * reserve system space, do all chunk btree updates and deletions, and
3294 * update the system chunk array in the superblock while holding this
3295 * mutex. This is for similar reasons as explained on the comment at
3296 * the top of btrfs_chunk_alloc();
3297 *
3298 * 2) Prevent races with the final phase of a device replace operation
3299 * that replaces the device object associated with the map's stripes,
3300 * because the device object's id can change at any time during that
3301 * final phase of the device replace operation
3302 * (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the
3303 * replaced device and then see it with an ID of
3304 * BTRFS_DEV_REPLACE_DEVID, which would cause a failure when updating
3305 * the device item, which does not exists on the chunk btree.
3306 * The finishing phase of device replace acquires both the
3307 * device_list_mutex and the chunk_mutex, in that order, so we are
3308 * safe by just acquiring the chunk_mutex.
3309 */
3310 trans->removing_chunk = true;
3311 mutex_lock(&fs_info->chunk_mutex);
3312
3313 check_system_chunk(trans, map->type);
3314
3315 ret = remove_chunk_item(trans, map, chunk_offset);
3316 /*
3317 * Normally we should not get -ENOSPC since we reserved space before
3318 * through the call to check_system_chunk().
3319 *
3320 * Despite our system space_info having enough free space, we may not
3321 * be able to allocate extents from its block groups, because all have
3322 * an incompatible profile, which will force us to allocate a new system
3323 * block group with the right profile, or right after we called
3324 * check_system_space() above, a scrub turned the only system block group
3325 * with enough free space into RO mode.
3326 * This is explained with more detail at do_chunk_alloc().
3327 *
3328 * So if we get -ENOSPC, allocate a new system chunk and retry once.
3329 */
3330 if (ret == -ENOSPC) {
3331 const u64 sys_flags = btrfs_system_alloc_profile(fs_info);
3332 struct btrfs_block_group *sys_bg;
3333
3334 sys_bg = btrfs_create_chunk(trans, sys_flags);
3335 if (IS_ERR(sys_bg)) {
3336 ret = PTR_ERR(sys_bg);
3337 btrfs_abort_transaction(trans, ret);
3338 goto out;
3339 }
3340
3341 ret = btrfs_chunk_alloc_add_chunk_item(trans, sys_bg);
3342 if (ret) {
3343 btrfs_abort_transaction(trans, ret);
3344 goto out;
3345 }
3346
3347 ret = remove_chunk_item(trans, map, chunk_offset);
3348 if (ret) {
3349 btrfs_abort_transaction(trans, ret);
3350 goto out;
3351 }
3352 } else if (ret) {
3353 btrfs_abort_transaction(trans, ret);
3354 goto out;
3355 }
3356
3357 trace_btrfs_chunk_free(fs_info, map, chunk_offset, map->chunk_len);
3358
3359 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
3360 ret = btrfs_del_sys_chunk(fs_info, chunk_offset);
3361 if (ret) {
3362 btrfs_abort_transaction(trans, ret);
3363 goto out;
3364 }
3365 }
3366
3367 mutex_unlock(&fs_info->chunk_mutex);
3368 trans->removing_chunk = false;
3369
3370 /*
3371 * We are done with chunk btree updates and deletions, so release the
3372 * system space we previously reserved (with check_system_chunk()).
3373 */
3374 btrfs_trans_release_chunk_metadata(trans);
3375
3376 ret = btrfs_remove_block_group(trans, map);
3377 if (ret) {
3378 btrfs_abort_transaction(trans, ret);
3379 goto out;
3380 }
3381
3382 out:
3383 if (trans->removing_chunk) {
3384 mutex_unlock(&fs_info->chunk_mutex);
3385 trans->removing_chunk = false;
3386 }
3387 /* once for us */
3388 btrfs_free_chunk_map(map);
3389 return ret;
3390 }
3391
btrfs_relocate_chunk(struct btrfs_fs_info * fs_info,u64 chunk_offset)3392 int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset)
3393 {
3394 struct btrfs_root *root = fs_info->chunk_root;
3395 struct btrfs_trans_handle *trans;
3396 struct btrfs_block_group *block_group;
3397 u64 length;
3398 int ret;
3399
3400 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
3401 btrfs_err(fs_info,
3402 "relocate: not supported on extent tree v2 yet");
3403 return -EINVAL;
3404 }
3405
3406 /*
3407 * Prevent races with automatic removal of unused block groups.
3408 * After we relocate and before we remove the chunk with offset
3409 * chunk_offset, automatic removal of the block group can kick in,
3410 * resulting in a failure when calling btrfs_remove_chunk() below.
3411 *
3412 * Make sure to acquire this mutex before doing a tree search (dev
3413 * or chunk trees) to find chunks. Otherwise the cleaner kthread might
3414 * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after
3415 * we release the path used to search the chunk/dev tree and before
3416 * the current task acquires this mutex and calls us.
3417 */
3418 lockdep_assert_held(&fs_info->reclaim_bgs_lock);
3419
3420 /* step one, relocate all the extents inside this chunk */
3421 btrfs_scrub_pause(fs_info);
3422 ret = btrfs_relocate_block_group(fs_info, chunk_offset);
3423 btrfs_scrub_continue(fs_info);
3424 if (ret) {
3425 /*
3426 * If we had a transaction abort, stop all running scrubs.
3427 * See transaction.c:cleanup_transaction() why we do it here.
3428 */
3429 if (BTRFS_FS_ERROR(fs_info))
3430 btrfs_scrub_cancel(fs_info);
3431 return ret;
3432 }
3433
3434 block_group = btrfs_lookup_block_group(fs_info, chunk_offset);
3435 if (!block_group)
3436 return -ENOENT;
3437 btrfs_discard_cancel_work(&fs_info->discard_ctl, block_group);
3438 length = block_group->length;
3439 btrfs_put_block_group(block_group);
3440
3441 /*
3442 * On a zoned file system, discard the whole block group, this will
3443 * trigger a REQ_OP_ZONE_RESET operation on the device zone. If
3444 * resetting the zone fails, don't treat it as a fatal problem from the
3445 * filesystem's point of view.
3446 */
3447 if (btrfs_is_zoned(fs_info)) {
3448 ret = btrfs_discard_extent(fs_info, chunk_offset, length, NULL);
3449 if (ret)
3450 btrfs_info(fs_info,
3451 "failed to reset zone %llu after relocation",
3452 chunk_offset);
3453 }
3454
3455 trans = btrfs_start_trans_remove_block_group(root->fs_info,
3456 chunk_offset);
3457 if (IS_ERR(trans)) {
3458 ret = PTR_ERR(trans);
3459 btrfs_handle_fs_error(root->fs_info, ret, NULL);
3460 return ret;
3461 }
3462
3463 /*
3464 * step two, delete the device extents and the
3465 * chunk tree entries
3466 */
3467 ret = btrfs_remove_chunk(trans, chunk_offset);
3468 btrfs_end_transaction(trans);
3469 return ret;
3470 }
3471
btrfs_relocate_sys_chunks(struct btrfs_fs_info * fs_info)3472 static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info)
3473 {
3474 struct btrfs_root *chunk_root = fs_info->chunk_root;
3475 struct btrfs_path *path;
3476 struct extent_buffer *leaf;
3477 struct btrfs_chunk *chunk;
3478 struct btrfs_key key;
3479 struct btrfs_key found_key;
3480 u64 chunk_type;
3481 bool retried = false;
3482 int failed = 0;
3483 int ret;
3484
3485 path = btrfs_alloc_path();
3486 if (!path)
3487 return -ENOMEM;
3488
3489 again:
3490 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3491 key.type = BTRFS_CHUNK_ITEM_KEY;
3492 key.offset = (u64)-1;
3493
3494 while (1) {
3495 mutex_lock(&fs_info->reclaim_bgs_lock);
3496 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3497 if (ret < 0) {
3498 mutex_unlock(&fs_info->reclaim_bgs_lock);
3499 goto error;
3500 }
3501 if (ret == 0) {
3502 /*
3503 * On the first search we would find chunk tree with
3504 * offset -1, which is not possible. On subsequent
3505 * loops this would find an existing item on an invalid
3506 * offset (one less than the previous one, wrong
3507 * alignment and size).
3508 */
3509 ret = -EUCLEAN;
3510 mutex_unlock(&fs_info->reclaim_bgs_lock);
3511 goto error;
3512 }
3513
3514 ret = btrfs_previous_item(chunk_root, path, key.objectid,
3515 key.type);
3516 if (ret)
3517 mutex_unlock(&fs_info->reclaim_bgs_lock);
3518 if (ret < 0)
3519 goto error;
3520 if (ret > 0)
3521 break;
3522
3523 leaf = path->nodes[0];
3524 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3525
3526 chunk = btrfs_item_ptr(leaf, path->slots[0],
3527 struct btrfs_chunk);
3528 chunk_type = btrfs_chunk_type(leaf, chunk);
3529 btrfs_release_path(path);
3530
3531 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
3532 ret = btrfs_relocate_chunk(fs_info, found_key.offset);
3533 if (ret == -ENOSPC)
3534 failed++;
3535 else
3536 BUG_ON(ret);
3537 }
3538 mutex_unlock(&fs_info->reclaim_bgs_lock);
3539
3540 if (found_key.offset == 0)
3541 break;
3542 key.offset = found_key.offset - 1;
3543 }
3544 ret = 0;
3545 if (failed && !retried) {
3546 failed = 0;
3547 retried = true;
3548 goto again;
3549 } else if (WARN_ON(failed && retried)) {
3550 ret = -ENOSPC;
3551 }
3552 error:
3553 btrfs_free_path(path);
3554 return ret;
3555 }
3556
3557 /*
3558 * return 1 : allocate a data chunk successfully,
3559 * return <0: errors during allocating a data chunk,
3560 * return 0 : no need to allocate a data chunk.
3561 */
btrfs_may_alloc_data_chunk(struct btrfs_fs_info * fs_info,u64 chunk_offset)3562 static int btrfs_may_alloc_data_chunk(struct btrfs_fs_info *fs_info,
3563 u64 chunk_offset)
3564 {
3565 struct btrfs_block_group *cache;
3566 u64 bytes_used;
3567 u64 chunk_type;
3568
3569 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3570 ASSERT(cache);
3571 chunk_type = cache->flags;
3572 btrfs_put_block_group(cache);
3573
3574 if (!(chunk_type & BTRFS_BLOCK_GROUP_DATA))
3575 return 0;
3576
3577 spin_lock(&fs_info->data_sinfo->lock);
3578 bytes_used = fs_info->data_sinfo->bytes_used;
3579 spin_unlock(&fs_info->data_sinfo->lock);
3580
3581 if (!bytes_used) {
3582 struct btrfs_trans_handle *trans;
3583 int ret;
3584
3585 trans = btrfs_join_transaction(fs_info->tree_root);
3586 if (IS_ERR(trans))
3587 return PTR_ERR(trans);
3588
3589 ret = btrfs_force_chunk_alloc(trans, BTRFS_BLOCK_GROUP_DATA);
3590 btrfs_end_transaction(trans);
3591 if (ret < 0)
3592 return ret;
3593 return 1;
3594 }
3595
3596 return 0;
3597 }
3598
btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args * cpu,const struct btrfs_disk_balance_args * disk)3599 static void btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args *cpu,
3600 const struct btrfs_disk_balance_args *disk)
3601 {
3602 memset(cpu, 0, sizeof(*cpu));
3603
3604 cpu->profiles = le64_to_cpu(disk->profiles);
3605 cpu->usage = le64_to_cpu(disk->usage);
3606 cpu->devid = le64_to_cpu(disk->devid);
3607 cpu->pstart = le64_to_cpu(disk->pstart);
3608 cpu->pend = le64_to_cpu(disk->pend);
3609 cpu->vstart = le64_to_cpu(disk->vstart);
3610 cpu->vend = le64_to_cpu(disk->vend);
3611 cpu->target = le64_to_cpu(disk->target);
3612 cpu->flags = le64_to_cpu(disk->flags);
3613 cpu->limit = le64_to_cpu(disk->limit);
3614 cpu->stripes_min = le32_to_cpu(disk->stripes_min);
3615 cpu->stripes_max = le32_to_cpu(disk->stripes_max);
3616 }
3617
btrfs_cpu_balance_args_to_disk(struct btrfs_disk_balance_args * disk,const struct btrfs_balance_args * cpu)3618 static void btrfs_cpu_balance_args_to_disk(struct btrfs_disk_balance_args *disk,
3619 const struct btrfs_balance_args *cpu)
3620 {
3621 memset(disk, 0, sizeof(*disk));
3622
3623 disk->profiles = cpu_to_le64(cpu->profiles);
3624 disk->usage = cpu_to_le64(cpu->usage);
3625 disk->devid = cpu_to_le64(cpu->devid);
3626 disk->pstart = cpu_to_le64(cpu->pstart);
3627 disk->pend = cpu_to_le64(cpu->pend);
3628 disk->vstart = cpu_to_le64(cpu->vstart);
3629 disk->vend = cpu_to_le64(cpu->vend);
3630 disk->target = cpu_to_le64(cpu->target);
3631 disk->flags = cpu_to_le64(cpu->flags);
3632 disk->limit = cpu_to_le64(cpu->limit);
3633 disk->stripes_min = cpu_to_le32(cpu->stripes_min);
3634 disk->stripes_max = cpu_to_le32(cpu->stripes_max);
3635 }
3636
insert_balance_item(struct btrfs_fs_info * fs_info,struct btrfs_balance_control * bctl)3637 static int insert_balance_item(struct btrfs_fs_info *fs_info,
3638 struct btrfs_balance_control *bctl)
3639 {
3640 struct btrfs_root *root = fs_info->tree_root;
3641 struct btrfs_trans_handle *trans;
3642 struct btrfs_balance_item *item;
3643 struct btrfs_disk_balance_args disk_bargs;
3644 struct btrfs_path *path;
3645 struct extent_buffer *leaf;
3646 struct btrfs_key key;
3647 int ret, err;
3648
3649 path = btrfs_alloc_path();
3650 if (!path)
3651 return -ENOMEM;
3652
3653 trans = btrfs_start_transaction(root, 0);
3654 if (IS_ERR(trans)) {
3655 btrfs_free_path(path);
3656 return PTR_ERR(trans);
3657 }
3658
3659 key.objectid = BTRFS_BALANCE_OBJECTID;
3660 key.type = BTRFS_TEMPORARY_ITEM_KEY;
3661 key.offset = 0;
3662
3663 ret = btrfs_insert_empty_item(trans, root, path, &key,
3664 sizeof(*item));
3665 if (ret)
3666 goto out;
3667
3668 leaf = path->nodes[0];
3669 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3670
3671 memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item));
3672
3673 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
3674 btrfs_set_balance_data(leaf, item, &disk_bargs);
3675 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
3676 btrfs_set_balance_meta(leaf, item, &disk_bargs);
3677 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
3678 btrfs_set_balance_sys(leaf, item, &disk_bargs);
3679 btrfs_set_balance_flags(leaf, item, bctl->flags);
3680 out:
3681 btrfs_free_path(path);
3682 err = btrfs_commit_transaction(trans);
3683 if (err && !ret)
3684 ret = err;
3685 return ret;
3686 }
3687
del_balance_item(struct btrfs_fs_info * fs_info)3688 static int del_balance_item(struct btrfs_fs_info *fs_info)
3689 {
3690 struct btrfs_root *root = fs_info->tree_root;
3691 struct btrfs_trans_handle *trans;
3692 struct btrfs_path *path;
3693 struct btrfs_key key;
3694 int ret, err;
3695
3696 path = btrfs_alloc_path();
3697 if (!path)
3698 return -ENOMEM;
3699
3700 trans = btrfs_start_transaction_fallback_global_rsv(root, 0);
3701 if (IS_ERR(trans)) {
3702 btrfs_free_path(path);
3703 return PTR_ERR(trans);
3704 }
3705
3706 key.objectid = BTRFS_BALANCE_OBJECTID;
3707 key.type = BTRFS_TEMPORARY_ITEM_KEY;
3708 key.offset = 0;
3709
3710 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3711 if (ret < 0)
3712 goto out;
3713 if (ret > 0) {
3714 ret = -ENOENT;
3715 goto out;
3716 }
3717
3718 ret = btrfs_del_item(trans, root, path);
3719 out:
3720 btrfs_free_path(path);
3721 err = btrfs_commit_transaction(trans);
3722 if (err && !ret)
3723 ret = err;
3724 return ret;
3725 }
3726
3727 /*
3728 * This is a heuristic used to reduce the number of chunks balanced on
3729 * resume after balance was interrupted.
3730 */
update_balance_args(struct btrfs_balance_control * bctl)3731 static void update_balance_args(struct btrfs_balance_control *bctl)
3732 {
3733 /*
3734 * Turn on soft mode for chunk types that were being converted.
3735 */
3736 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
3737 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
3738 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
3739 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
3740 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
3741 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
3742
3743 /*
3744 * Turn on usage filter if is not already used. The idea is
3745 * that chunks that we have already balanced should be
3746 * reasonably full. Don't do it for chunks that are being
3747 * converted - that will keep us from relocating unconverted
3748 * (albeit full) chunks.
3749 */
3750 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3751 !(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3752 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3753 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
3754 bctl->data.usage = 90;
3755 }
3756 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3757 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3758 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3759 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
3760 bctl->sys.usage = 90;
3761 }
3762 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3763 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3764 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3765 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
3766 bctl->meta.usage = 90;
3767 }
3768 }
3769
3770 /*
3771 * Clear the balance status in fs_info and delete the balance item from disk.
3772 */
reset_balance_state(struct btrfs_fs_info * fs_info)3773 static void reset_balance_state(struct btrfs_fs_info *fs_info)
3774 {
3775 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3776 int ret;
3777
3778 ASSERT(fs_info->balance_ctl);
3779
3780 spin_lock(&fs_info->balance_lock);
3781 fs_info->balance_ctl = NULL;
3782 spin_unlock(&fs_info->balance_lock);
3783
3784 kfree(bctl);
3785 ret = del_balance_item(fs_info);
3786 if (ret)
3787 btrfs_handle_fs_error(fs_info, ret, NULL);
3788 }
3789
3790 /*
3791 * Balance filters. Return 1 if chunk should be filtered out
3792 * (should not be balanced).
3793 */
chunk_profiles_filter(u64 chunk_type,struct btrfs_balance_args * bargs)3794 static int chunk_profiles_filter(u64 chunk_type,
3795 struct btrfs_balance_args *bargs)
3796 {
3797 chunk_type = chunk_to_extended(chunk_type) &
3798 BTRFS_EXTENDED_PROFILE_MASK;
3799
3800 if (bargs->profiles & chunk_type)
3801 return 0;
3802
3803 return 1;
3804 }
3805
chunk_usage_range_filter(struct btrfs_fs_info * fs_info,u64 chunk_offset,struct btrfs_balance_args * bargs)3806 static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
3807 struct btrfs_balance_args *bargs)
3808 {
3809 struct btrfs_block_group *cache;
3810 u64 chunk_used;
3811 u64 user_thresh_min;
3812 u64 user_thresh_max;
3813 int ret = 1;
3814
3815 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3816 chunk_used = cache->used;
3817
3818 if (bargs->usage_min == 0)
3819 user_thresh_min = 0;
3820 else
3821 user_thresh_min = mult_perc(cache->length, bargs->usage_min);
3822
3823 if (bargs->usage_max == 0)
3824 user_thresh_max = 1;
3825 else if (bargs->usage_max > 100)
3826 user_thresh_max = cache->length;
3827 else
3828 user_thresh_max = mult_perc(cache->length, bargs->usage_max);
3829
3830 if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max)
3831 ret = 0;
3832
3833 btrfs_put_block_group(cache);
3834 return ret;
3835 }
3836
chunk_usage_filter(struct btrfs_fs_info * fs_info,u64 chunk_offset,struct btrfs_balance_args * bargs)3837 static int chunk_usage_filter(struct btrfs_fs_info *fs_info,
3838 u64 chunk_offset, struct btrfs_balance_args *bargs)
3839 {
3840 struct btrfs_block_group *cache;
3841 u64 chunk_used, user_thresh;
3842 int ret = 1;
3843
3844 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3845 chunk_used = cache->used;
3846
3847 if (bargs->usage_min == 0)
3848 user_thresh = 1;
3849 else if (bargs->usage > 100)
3850 user_thresh = cache->length;
3851 else
3852 user_thresh = mult_perc(cache->length, bargs->usage);
3853
3854 if (chunk_used < user_thresh)
3855 ret = 0;
3856
3857 btrfs_put_block_group(cache);
3858 return ret;
3859 }
3860
chunk_devid_filter(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_balance_args * bargs)3861 static int chunk_devid_filter(struct extent_buffer *leaf,
3862 struct btrfs_chunk *chunk,
3863 struct btrfs_balance_args *bargs)
3864 {
3865 struct btrfs_stripe *stripe;
3866 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3867 int i;
3868
3869 for (i = 0; i < num_stripes; i++) {
3870 stripe = btrfs_stripe_nr(chunk, i);
3871 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
3872 return 0;
3873 }
3874
3875 return 1;
3876 }
3877
calc_data_stripes(u64 type,int num_stripes)3878 static u64 calc_data_stripes(u64 type, int num_stripes)
3879 {
3880 const int index = btrfs_bg_flags_to_raid_index(type);
3881 const int ncopies = btrfs_raid_array[index].ncopies;
3882 const int nparity = btrfs_raid_array[index].nparity;
3883
3884 return (num_stripes - nparity) / ncopies;
3885 }
3886
3887 /* [pstart, pend) */
chunk_drange_filter(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_balance_args * bargs)3888 static int chunk_drange_filter(struct extent_buffer *leaf,
3889 struct btrfs_chunk *chunk,
3890 struct btrfs_balance_args *bargs)
3891 {
3892 struct btrfs_stripe *stripe;
3893 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3894 u64 stripe_offset;
3895 u64 stripe_length;
3896 u64 type;
3897 int factor;
3898 int i;
3899
3900 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3901 return 0;
3902
3903 type = btrfs_chunk_type(leaf, chunk);
3904 factor = calc_data_stripes(type, num_stripes);
3905
3906 for (i = 0; i < num_stripes; i++) {
3907 stripe = btrfs_stripe_nr(chunk, i);
3908 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3909 continue;
3910
3911 stripe_offset = btrfs_stripe_offset(leaf, stripe);
3912 stripe_length = btrfs_chunk_length(leaf, chunk);
3913 stripe_length = div_u64(stripe_length, factor);
3914
3915 if (stripe_offset < bargs->pend &&
3916 stripe_offset + stripe_length > bargs->pstart)
3917 return 0;
3918 }
3919
3920 return 1;
3921 }
3922
3923 /* [vstart, vend) */
chunk_vrange_filter(struct extent_buffer * leaf,struct btrfs_chunk * chunk,u64 chunk_offset,struct btrfs_balance_args * bargs)3924 static int chunk_vrange_filter(struct extent_buffer *leaf,
3925 struct btrfs_chunk *chunk,
3926 u64 chunk_offset,
3927 struct btrfs_balance_args *bargs)
3928 {
3929 if (chunk_offset < bargs->vend &&
3930 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
3931 /* at least part of the chunk is inside this vrange */
3932 return 0;
3933
3934 return 1;
3935 }
3936
chunk_stripes_range_filter(struct extent_buffer * leaf,struct btrfs_chunk * chunk,struct btrfs_balance_args * bargs)3937 static int chunk_stripes_range_filter(struct extent_buffer *leaf,
3938 struct btrfs_chunk *chunk,
3939 struct btrfs_balance_args *bargs)
3940 {
3941 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3942
3943 if (bargs->stripes_min <= num_stripes
3944 && num_stripes <= bargs->stripes_max)
3945 return 0;
3946
3947 return 1;
3948 }
3949
chunk_soft_convert_filter(u64 chunk_type,struct btrfs_balance_args * bargs)3950 static int chunk_soft_convert_filter(u64 chunk_type,
3951 struct btrfs_balance_args *bargs)
3952 {
3953 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
3954 return 0;
3955
3956 chunk_type = chunk_to_extended(chunk_type) &
3957 BTRFS_EXTENDED_PROFILE_MASK;
3958
3959 if (bargs->target == chunk_type)
3960 return 1;
3961
3962 return 0;
3963 }
3964
should_balance_chunk(struct extent_buffer * leaf,struct btrfs_chunk * chunk,u64 chunk_offset)3965 static int should_balance_chunk(struct extent_buffer *leaf,
3966 struct btrfs_chunk *chunk, u64 chunk_offset)
3967 {
3968 struct btrfs_fs_info *fs_info = leaf->fs_info;
3969 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3970 struct btrfs_balance_args *bargs = NULL;
3971 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
3972
3973 /* type filter */
3974 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
3975 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
3976 return 0;
3977 }
3978
3979 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3980 bargs = &bctl->data;
3981 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3982 bargs = &bctl->sys;
3983 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3984 bargs = &bctl->meta;
3985
3986 /* profiles filter */
3987 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
3988 chunk_profiles_filter(chunk_type, bargs)) {
3989 return 0;
3990 }
3991
3992 /* usage filter */
3993 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
3994 chunk_usage_filter(fs_info, chunk_offset, bargs)) {
3995 return 0;
3996 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3997 chunk_usage_range_filter(fs_info, chunk_offset, bargs)) {
3998 return 0;
3999 }
4000
4001 /* devid filter */
4002 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
4003 chunk_devid_filter(leaf, chunk, bargs)) {
4004 return 0;
4005 }
4006
4007 /* drange filter, makes sense only with devid filter */
4008 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
4009 chunk_drange_filter(leaf, chunk, bargs)) {
4010 return 0;
4011 }
4012
4013 /* vrange filter */
4014 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
4015 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
4016 return 0;
4017 }
4018
4019 /* stripes filter */
4020 if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) &&
4021 chunk_stripes_range_filter(leaf, chunk, bargs)) {
4022 return 0;
4023 }
4024
4025 /* soft profile changing mode */
4026 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
4027 chunk_soft_convert_filter(chunk_type, bargs)) {
4028 return 0;
4029 }
4030
4031 /*
4032 * limited by count, must be the last filter
4033 */
4034 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
4035 if (bargs->limit == 0)
4036 return 0;
4037 else
4038 bargs->limit--;
4039 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) {
4040 /*
4041 * Same logic as the 'limit' filter; the minimum cannot be
4042 * determined here because we do not have the global information
4043 * about the count of all chunks that satisfy the filters.
4044 */
4045 if (bargs->limit_max == 0)
4046 return 0;
4047 else
4048 bargs->limit_max--;
4049 }
4050
4051 return 1;
4052 }
4053
__btrfs_balance(struct btrfs_fs_info * fs_info)4054 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
4055 {
4056 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4057 struct btrfs_root *chunk_root = fs_info->chunk_root;
4058 u64 chunk_type;
4059 struct btrfs_chunk *chunk;
4060 struct btrfs_path *path = NULL;
4061 struct btrfs_key key;
4062 struct btrfs_key found_key;
4063 struct extent_buffer *leaf;
4064 int slot;
4065 int ret;
4066 int enospc_errors = 0;
4067 bool counting = true;
4068 /* The single value limit and min/max limits use the same bytes in the */
4069 u64 limit_data = bctl->data.limit;
4070 u64 limit_meta = bctl->meta.limit;
4071 u64 limit_sys = bctl->sys.limit;
4072 u32 count_data = 0;
4073 u32 count_meta = 0;
4074 u32 count_sys = 0;
4075 int chunk_reserved = 0;
4076
4077 path = btrfs_alloc_path();
4078 if (!path) {
4079 ret = -ENOMEM;
4080 goto error;
4081 }
4082
4083 /* zero out stat counters */
4084 spin_lock(&fs_info->balance_lock);
4085 memset(&bctl->stat, 0, sizeof(bctl->stat));
4086 spin_unlock(&fs_info->balance_lock);
4087 again:
4088 if (!counting) {
4089 /*
4090 * The single value limit and min/max limits use the same bytes
4091 * in the
4092 */
4093 bctl->data.limit = limit_data;
4094 bctl->meta.limit = limit_meta;
4095 bctl->sys.limit = limit_sys;
4096 }
4097 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4098 key.type = BTRFS_CHUNK_ITEM_KEY;
4099 key.offset = (u64)-1;
4100
4101 while (1) {
4102 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
4103 atomic_read(&fs_info->balance_cancel_req)) {
4104 ret = -ECANCELED;
4105 goto error;
4106 }
4107
4108 mutex_lock(&fs_info->reclaim_bgs_lock);
4109 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
4110 if (ret < 0) {
4111 mutex_unlock(&fs_info->reclaim_bgs_lock);
4112 goto error;
4113 }
4114
4115 /*
4116 * this shouldn't happen, it means the last relocate
4117 * failed
4118 */
4119 if (ret == 0)
4120 BUG(); /* FIXME break ? */
4121
4122 ret = btrfs_previous_item(chunk_root, path, 0,
4123 BTRFS_CHUNK_ITEM_KEY);
4124 if (ret) {
4125 mutex_unlock(&fs_info->reclaim_bgs_lock);
4126 ret = 0;
4127 break;
4128 }
4129
4130 leaf = path->nodes[0];
4131 slot = path->slots[0];
4132 btrfs_item_key_to_cpu(leaf, &found_key, slot);
4133
4134 if (found_key.objectid != key.objectid) {
4135 mutex_unlock(&fs_info->reclaim_bgs_lock);
4136 break;
4137 }
4138
4139 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
4140 chunk_type = btrfs_chunk_type(leaf, chunk);
4141
4142 if (!counting) {
4143 spin_lock(&fs_info->balance_lock);
4144 bctl->stat.considered++;
4145 spin_unlock(&fs_info->balance_lock);
4146 }
4147
4148 ret = should_balance_chunk(leaf, chunk, found_key.offset);
4149
4150 btrfs_release_path(path);
4151 if (!ret) {
4152 mutex_unlock(&fs_info->reclaim_bgs_lock);
4153 goto loop;
4154 }
4155
4156 if (counting) {
4157 mutex_unlock(&fs_info->reclaim_bgs_lock);
4158 spin_lock(&fs_info->balance_lock);
4159 bctl->stat.expected++;
4160 spin_unlock(&fs_info->balance_lock);
4161
4162 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
4163 count_data++;
4164 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
4165 count_sys++;
4166 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
4167 count_meta++;
4168
4169 goto loop;
4170 }
4171
4172 /*
4173 * Apply limit_min filter, no need to check if the LIMITS
4174 * filter is used, limit_min is 0 by default
4175 */
4176 if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
4177 count_data < bctl->data.limit_min)
4178 || ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) &&
4179 count_meta < bctl->meta.limit_min)
4180 || ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) &&
4181 count_sys < bctl->sys.limit_min)) {
4182 mutex_unlock(&fs_info->reclaim_bgs_lock);
4183 goto loop;
4184 }
4185
4186 if (!chunk_reserved) {
4187 /*
4188 * We may be relocating the only data chunk we have,
4189 * which could potentially end up with losing data's
4190 * raid profile, so lets allocate an empty one in
4191 * advance.
4192 */
4193 ret = btrfs_may_alloc_data_chunk(fs_info,
4194 found_key.offset);
4195 if (ret < 0) {
4196 mutex_unlock(&fs_info->reclaim_bgs_lock);
4197 goto error;
4198 } else if (ret == 1) {
4199 chunk_reserved = 1;
4200 }
4201 }
4202
4203 ret = btrfs_relocate_chunk(fs_info, found_key.offset);
4204 mutex_unlock(&fs_info->reclaim_bgs_lock);
4205 if (ret == -ENOSPC) {
4206 enospc_errors++;
4207 } else if (ret == -ETXTBSY) {
4208 btrfs_info(fs_info,
4209 "skipping relocation of block group %llu due to active swapfile",
4210 found_key.offset);
4211 ret = 0;
4212 } else if (ret) {
4213 goto error;
4214 } else {
4215 spin_lock(&fs_info->balance_lock);
4216 bctl->stat.completed++;
4217 spin_unlock(&fs_info->balance_lock);
4218 }
4219 loop:
4220 if (found_key.offset == 0)
4221 break;
4222 key.offset = found_key.offset - 1;
4223 }
4224
4225 if (counting) {
4226 btrfs_release_path(path);
4227 counting = false;
4228 goto again;
4229 }
4230 error:
4231 btrfs_free_path(path);
4232 if (enospc_errors) {
4233 btrfs_info(fs_info, "%d enospc errors during balance",
4234 enospc_errors);
4235 if (!ret)
4236 ret = -ENOSPC;
4237 }
4238
4239 return ret;
4240 }
4241
4242 /*
4243 * See if a given profile is valid and reduced.
4244 *
4245 * @flags: profile to validate
4246 * @extended: if true @flags is treated as an extended profile
4247 */
alloc_profile_is_valid(u64 flags,int extended)4248 static int alloc_profile_is_valid(u64 flags, int extended)
4249 {
4250 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
4251 BTRFS_BLOCK_GROUP_PROFILE_MASK);
4252
4253 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
4254
4255 /* 1) check that all other bits are zeroed */
4256 if (flags & ~mask)
4257 return 0;
4258
4259 /* 2) see if profile is reduced */
4260 if (flags == 0)
4261 return !extended; /* "0" is valid for usual profiles */
4262
4263 return has_single_bit_set(flags);
4264 }
4265
4266 /*
4267 * Validate target profile against allowed profiles and return true if it's OK.
4268 * Otherwise print the error message and return false.
4269 */
validate_convert_profile(struct btrfs_fs_info * fs_info,const struct btrfs_balance_args * bargs,u64 allowed,const char * type)4270 static inline int validate_convert_profile(struct btrfs_fs_info *fs_info,
4271 const struct btrfs_balance_args *bargs,
4272 u64 allowed, const char *type)
4273 {
4274 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
4275 return true;
4276
4277 /* Profile is valid and does not have bits outside of the allowed set */
4278 if (alloc_profile_is_valid(bargs->target, 1) &&
4279 (bargs->target & ~allowed) == 0)
4280 return true;
4281
4282 btrfs_err(fs_info, "balance: invalid convert %s profile %s",
4283 type, btrfs_bg_type_to_raid_name(bargs->target));
4284 return false;
4285 }
4286
4287 /*
4288 * Fill @buf with textual description of balance filter flags @bargs, up to
4289 * @size_buf including the terminating null. The output may be trimmed if it
4290 * does not fit into the provided buffer.
4291 */
describe_balance_args(struct btrfs_balance_args * bargs,char * buf,u32 size_buf)4292 static void describe_balance_args(struct btrfs_balance_args *bargs, char *buf,
4293 u32 size_buf)
4294 {
4295 int ret;
4296 u32 size_bp = size_buf;
4297 char *bp = buf;
4298 u64 flags = bargs->flags;
4299 char tmp_buf[128] = {'\0'};
4300
4301 if (!flags)
4302 return;
4303
4304 #define CHECK_APPEND_NOARG(a) \
4305 do { \
4306 ret = snprintf(bp, size_bp, (a)); \
4307 if (ret < 0 || ret >= size_bp) \
4308 goto out_overflow; \
4309 size_bp -= ret; \
4310 bp += ret; \
4311 } while (0)
4312
4313 #define CHECK_APPEND_1ARG(a, v1) \
4314 do { \
4315 ret = snprintf(bp, size_bp, (a), (v1)); \
4316 if (ret < 0 || ret >= size_bp) \
4317 goto out_overflow; \
4318 size_bp -= ret; \
4319 bp += ret; \
4320 } while (0)
4321
4322 #define CHECK_APPEND_2ARG(a, v1, v2) \
4323 do { \
4324 ret = snprintf(bp, size_bp, (a), (v1), (v2)); \
4325 if (ret < 0 || ret >= size_bp) \
4326 goto out_overflow; \
4327 size_bp -= ret; \
4328 bp += ret; \
4329 } while (0)
4330
4331 if (flags & BTRFS_BALANCE_ARGS_CONVERT)
4332 CHECK_APPEND_1ARG("convert=%s,",
4333 btrfs_bg_type_to_raid_name(bargs->target));
4334
4335 if (flags & BTRFS_BALANCE_ARGS_SOFT)
4336 CHECK_APPEND_NOARG("soft,");
4337
4338 if (flags & BTRFS_BALANCE_ARGS_PROFILES) {
4339 btrfs_describe_block_groups(bargs->profiles, tmp_buf,
4340 sizeof(tmp_buf));
4341 CHECK_APPEND_1ARG("profiles=%s,", tmp_buf);
4342 }
4343
4344 if (flags & BTRFS_BALANCE_ARGS_USAGE)
4345 CHECK_APPEND_1ARG("usage=%llu,", bargs->usage);
4346
4347 if (flags & BTRFS_BALANCE_ARGS_USAGE_RANGE)
4348 CHECK_APPEND_2ARG("usage=%u..%u,",
4349 bargs->usage_min, bargs->usage_max);
4350
4351 if (flags & BTRFS_BALANCE_ARGS_DEVID)
4352 CHECK_APPEND_1ARG("devid=%llu,", bargs->devid);
4353
4354 if (flags & BTRFS_BALANCE_ARGS_DRANGE)
4355 CHECK_APPEND_2ARG("drange=%llu..%llu,",
4356 bargs->pstart, bargs->pend);
4357
4358 if (flags & BTRFS_BALANCE_ARGS_VRANGE)
4359 CHECK_APPEND_2ARG("vrange=%llu..%llu,",
4360 bargs->vstart, bargs->vend);
4361
4362 if (flags & BTRFS_BALANCE_ARGS_LIMIT)
4363 CHECK_APPEND_1ARG("limit=%llu,", bargs->limit);
4364
4365 if (flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)
4366 CHECK_APPEND_2ARG("limit=%u..%u,",
4367 bargs->limit_min, bargs->limit_max);
4368
4369 if (flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE)
4370 CHECK_APPEND_2ARG("stripes=%u..%u,",
4371 bargs->stripes_min, bargs->stripes_max);
4372
4373 #undef CHECK_APPEND_2ARG
4374 #undef CHECK_APPEND_1ARG
4375 #undef CHECK_APPEND_NOARG
4376
4377 out_overflow:
4378
4379 if (size_bp < size_buf)
4380 buf[size_buf - size_bp - 1] = '\0'; /* remove last , */
4381 else
4382 buf[0] = '\0';
4383 }
4384
describe_balance_start_or_resume(struct btrfs_fs_info * fs_info)4385 static void describe_balance_start_or_resume(struct btrfs_fs_info *fs_info)
4386 {
4387 u32 size_buf = 1024;
4388 char tmp_buf[192] = {'\0'};
4389 char *buf;
4390 char *bp;
4391 u32 size_bp = size_buf;
4392 int ret;
4393 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4394
4395 buf = kzalloc(size_buf, GFP_KERNEL);
4396 if (!buf)
4397 return;
4398
4399 bp = buf;
4400
4401 #define CHECK_APPEND_1ARG(a, v1) \
4402 do { \
4403 ret = snprintf(bp, size_bp, (a), (v1)); \
4404 if (ret < 0 || ret >= size_bp) \
4405 goto out_overflow; \
4406 size_bp -= ret; \
4407 bp += ret; \
4408 } while (0)
4409
4410 if (bctl->flags & BTRFS_BALANCE_FORCE)
4411 CHECK_APPEND_1ARG("%s", "-f ");
4412
4413 if (bctl->flags & BTRFS_BALANCE_DATA) {
4414 describe_balance_args(&bctl->data, tmp_buf, sizeof(tmp_buf));
4415 CHECK_APPEND_1ARG("-d%s ", tmp_buf);
4416 }
4417
4418 if (bctl->flags & BTRFS_BALANCE_METADATA) {
4419 describe_balance_args(&bctl->meta, tmp_buf, sizeof(tmp_buf));
4420 CHECK_APPEND_1ARG("-m%s ", tmp_buf);
4421 }
4422
4423 if (bctl->flags & BTRFS_BALANCE_SYSTEM) {
4424 describe_balance_args(&bctl->sys, tmp_buf, sizeof(tmp_buf));
4425 CHECK_APPEND_1ARG("-s%s ", tmp_buf);
4426 }
4427
4428 #undef CHECK_APPEND_1ARG
4429
4430 out_overflow:
4431
4432 if (size_bp < size_buf)
4433 buf[size_buf - size_bp - 1] = '\0'; /* remove last " " */
4434 btrfs_info(fs_info, "balance: %s %s",
4435 (bctl->flags & BTRFS_BALANCE_RESUME) ?
4436 "resume" : "start", buf);
4437
4438 kfree(buf);
4439 }
4440
4441 /*
4442 * Should be called with balance mutexe held
4443 */
btrfs_balance(struct btrfs_fs_info * fs_info,struct btrfs_balance_control * bctl,struct btrfs_ioctl_balance_args * bargs)4444 int btrfs_balance(struct btrfs_fs_info *fs_info,
4445 struct btrfs_balance_control *bctl,
4446 struct btrfs_ioctl_balance_args *bargs)
4447 {
4448 u64 meta_target, data_target;
4449 u64 allowed;
4450 int mixed = 0;
4451 int ret;
4452 u64 num_devices;
4453 unsigned seq;
4454 bool reducing_redundancy;
4455 bool paused = false;
4456 int i;
4457
4458 if (btrfs_fs_closing(fs_info) ||
4459 atomic_read(&fs_info->balance_pause_req) ||
4460 btrfs_should_cancel_balance(fs_info)) {
4461 ret = -EINVAL;
4462 goto out;
4463 }
4464
4465 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
4466 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
4467 mixed = 1;
4468
4469 /*
4470 * In case of mixed groups both data and meta should be picked,
4471 * and identical options should be given for both of them.
4472 */
4473 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
4474 if (mixed && (bctl->flags & allowed)) {
4475 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
4476 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
4477 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
4478 btrfs_err(fs_info,
4479 "balance: mixed groups data and metadata options must be the same");
4480 ret = -EINVAL;
4481 goto out;
4482 }
4483 }
4484
4485 /*
4486 * rw_devices will not change at the moment, device add/delete/replace
4487 * are exclusive
4488 */
4489 num_devices = fs_info->fs_devices->rw_devices;
4490
4491 /*
4492 * SINGLE profile on-disk has no profile bit, but in-memory we have a
4493 * special bit for it, to make it easier to distinguish. Thus we need
4494 * to set it manually, or balance would refuse the profile.
4495 */
4496 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
4497 for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++)
4498 if (num_devices >= btrfs_raid_array[i].devs_min)
4499 allowed |= btrfs_raid_array[i].bg_flag;
4500
4501 if (!validate_convert_profile(fs_info, &bctl->data, allowed, "data") ||
4502 !validate_convert_profile(fs_info, &bctl->meta, allowed, "metadata") ||
4503 !validate_convert_profile(fs_info, &bctl->sys, allowed, "system")) {
4504 ret = -EINVAL;
4505 goto out;
4506 }
4507
4508 /*
4509 * Allow to reduce metadata or system integrity only if force set for
4510 * profiles with redundancy (copies, parity)
4511 */
4512 allowed = 0;
4513 for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) {
4514 if (btrfs_raid_array[i].ncopies >= 2 ||
4515 btrfs_raid_array[i].tolerated_failures >= 1)
4516 allowed |= btrfs_raid_array[i].bg_flag;
4517 }
4518 do {
4519 seq = read_seqbegin(&fs_info->profiles_lock);
4520
4521 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
4522 (fs_info->avail_system_alloc_bits & allowed) &&
4523 !(bctl->sys.target & allowed)) ||
4524 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
4525 (fs_info->avail_metadata_alloc_bits & allowed) &&
4526 !(bctl->meta.target & allowed)))
4527 reducing_redundancy = true;
4528 else
4529 reducing_redundancy = false;
4530
4531 /* if we're not converting, the target field is uninitialized */
4532 meta_target = (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) ?
4533 bctl->meta.target : fs_info->avail_metadata_alloc_bits;
4534 data_target = (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) ?
4535 bctl->data.target : fs_info->avail_data_alloc_bits;
4536 } while (read_seqretry(&fs_info->profiles_lock, seq));
4537
4538 if (reducing_redundancy) {
4539 if (bctl->flags & BTRFS_BALANCE_FORCE) {
4540 btrfs_info(fs_info,
4541 "balance: force reducing metadata redundancy");
4542 } else {
4543 btrfs_err(fs_info,
4544 "balance: reduces metadata redundancy, use --force if you want this");
4545 ret = -EINVAL;
4546 goto out;
4547 }
4548 }
4549
4550 if (btrfs_get_num_tolerated_disk_barrier_failures(meta_target) <
4551 btrfs_get_num_tolerated_disk_barrier_failures(data_target)) {
4552 btrfs_warn(fs_info,
4553 "balance: metadata profile %s has lower redundancy than data profile %s",
4554 btrfs_bg_type_to_raid_name(meta_target),
4555 btrfs_bg_type_to_raid_name(data_target));
4556 }
4557
4558 ret = insert_balance_item(fs_info, bctl);
4559 if (ret && ret != -EEXIST)
4560 goto out;
4561
4562 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
4563 BUG_ON(ret == -EEXIST);
4564 BUG_ON(fs_info->balance_ctl);
4565 spin_lock(&fs_info->balance_lock);
4566 fs_info->balance_ctl = bctl;
4567 spin_unlock(&fs_info->balance_lock);
4568 } else {
4569 BUG_ON(ret != -EEXIST);
4570 spin_lock(&fs_info->balance_lock);
4571 update_balance_args(bctl);
4572 spin_unlock(&fs_info->balance_lock);
4573 }
4574
4575 ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4576 set_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
4577 describe_balance_start_or_resume(fs_info);
4578 mutex_unlock(&fs_info->balance_mutex);
4579
4580 ret = __btrfs_balance(fs_info);
4581
4582 mutex_lock(&fs_info->balance_mutex);
4583 if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
4584 btrfs_info(fs_info, "balance: paused");
4585 btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
4586 paused = true;
4587 }
4588 /*
4589 * Balance can be canceled by:
4590 *
4591 * - Regular cancel request
4592 * Then ret == -ECANCELED and balance_cancel_req > 0
4593 *
4594 * - Fatal signal to "btrfs" process
4595 * Either the signal caught by wait_reserve_ticket() and callers
4596 * got -EINTR, or caught by btrfs_should_cancel_balance() and
4597 * got -ECANCELED.
4598 * Either way, in this case balance_cancel_req = 0, and
4599 * ret == -EINTR or ret == -ECANCELED.
4600 *
4601 * So here we only check the return value to catch canceled balance.
4602 */
4603 else if (ret == -ECANCELED || ret == -EINTR)
4604 btrfs_info(fs_info, "balance: canceled");
4605 else
4606 btrfs_info(fs_info, "balance: ended with status: %d", ret);
4607
4608 clear_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags);
4609
4610 if (bargs) {
4611 memset(bargs, 0, sizeof(*bargs));
4612 btrfs_update_ioctl_balance_args(fs_info, bargs);
4613 }
4614
4615 /* We didn't pause, we can clean everything up. */
4616 if (!paused) {
4617 reset_balance_state(fs_info);
4618 btrfs_exclop_finish(fs_info);
4619 }
4620
4621 wake_up(&fs_info->balance_wait_q);
4622
4623 return ret;
4624 out:
4625 if (bctl->flags & BTRFS_BALANCE_RESUME)
4626 reset_balance_state(fs_info);
4627 else
4628 kfree(bctl);
4629 btrfs_exclop_finish(fs_info);
4630
4631 return ret;
4632 }
4633
balance_kthread(void * data)4634 static int balance_kthread(void *data)
4635 {
4636 struct btrfs_fs_info *fs_info = data;
4637 int ret = 0;
4638
4639 sb_start_write(fs_info->sb);
4640 mutex_lock(&fs_info->balance_mutex);
4641 if (fs_info->balance_ctl)
4642 ret = btrfs_balance(fs_info, fs_info->balance_ctl, NULL);
4643 mutex_unlock(&fs_info->balance_mutex);
4644 sb_end_write(fs_info->sb);
4645
4646 return ret;
4647 }
4648
btrfs_resume_balance_async(struct btrfs_fs_info * fs_info)4649 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
4650 {
4651 struct task_struct *tsk;
4652
4653 mutex_lock(&fs_info->balance_mutex);
4654 if (!fs_info->balance_ctl) {
4655 mutex_unlock(&fs_info->balance_mutex);
4656 return 0;
4657 }
4658 mutex_unlock(&fs_info->balance_mutex);
4659
4660 if (btrfs_test_opt(fs_info, SKIP_BALANCE)) {
4661 btrfs_info(fs_info, "balance: resume skipped");
4662 return 0;
4663 }
4664
4665 spin_lock(&fs_info->super_lock);
4666 ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
4667 fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;
4668 spin_unlock(&fs_info->super_lock);
4669 /*
4670 * A ro->rw remount sequence should continue with the paused balance
4671 * regardless of who pauses it, system or the user as of now, so set
4672 * the resume flag.
4673 */
4674 spin_lock(&fs_info->balance_lock);
4675 fs_info->balance_ctl->flags |= BTRFS_BALANCE_RESUME;
4676 spin_unlock(&fs_info->balance_lock);
4677
4678 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
4679 return PTR_ERR_OR_ZERO(tsk);
4680 }
4681
btrfs_recover_balance(struct btrfs_fs_info * fs_info)4682 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
4683 {
4684 struct btrfs_balance_control *bctl;
4685 struct btrfs_balance_item *item;
4686 struct btrfs_disk_balance_args disk_bargs;
4687 struct btrfs_path *path;
4688 struct extent_buffer *leaf;
4689 struct btrfs_key key;
4690 int ret;
4691
4692 path = btrfs_alloc_path();
4693 if (!path)
4694 return -ENOMEM;
4695
4696 key.objectid = BTRFS_BALANCE_OBJECTID;
4697 key.type = BTRFS_TEMPORARY_ITEM_KEY;
4698 key.offset = 0;
4699
4700 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
4701 if (ret < 0)
4702 goto out;
4703 if (ret > 0) { /* ret = -ENOENT; */
4704 ret = 0;
4705 goto out;
4706 }
4707
4708 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4709 if (!bctl) {
4710 ret = -ENOMEM;
4711 goto out;
4712 }
4713
4714 leaf = path->nodes[0];
4715 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
4716
4717 bctl->flags = btrfs_balance_flags(leaf, item);
4718 bctl->flags |= BTRFS_BALANCE_RESUME;
4719
4720 btrfs_balance_data(leaf, item, &disk_bargs);
4721 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
4722 btrfs_balance_meta(leaf, item, &disk_bargs);
4723 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
4724 btrfs_balance_sys(leaf, item, &disk_bargs);
4725 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
4726
4727 /*
4728 * This should never happen, as the paused balance state is recovered
4729 * during mount without any chance of other exclusive ops to collide.
4730 *
4731 * This gives the exclusive op status to balance and keeps in paused
4732 * state until user intervention (cancel or umount). If the ownership
4733 * cannot be assigned, show a message but do not fail. The balance
4734 * is in a paused state and must have fs_info::balance_ctl properly
4735 * set up.
4736 */
4737 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED))
4738 btrfs_warn(fs_info,
4739 "balance: cannot set exclusive op status, resume manually");
4740
4741 btrfs_release_path(path);
4742
4743 mutex_lock(&fs_info->balance_mutex);
4744 BUG_ON(fs_info->balance_ctl);
4745 spin_lock(&fs_info->balance_lock);
4746 fs_info->balance_ctl = bctl;
4747 spin_unlock(&fs_info->balance_lock);
4748 mutex_unlock(&fs_info->balance_mutex);
4749 out:
4750 btrfs_free_path(path);
4751 return ret;
4752 }
4753
btrfs_pause_balance(struct btrfs_fs_info * fs_info)4754 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
4755 {
4756 int ret = 0;
4757
4758 mutex_lock(&fs_info->balance_mutex);
4759 if (!fs_info->balance_ctl) {
4760 mutex_unlock(&fs_info->balance_mutex);
4761 return -ENOTCONN;
4762 }
4763
4764 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4765 atomic_inc(&fs_info->balance_pause_req);
4766 mutex_unlock(&fs_info->balance_mutex);
4767
4768 wait_event(fs_info->balance_wait_q,
4769 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4770
4771 mutex_lock(&fs_info->balance_mutex);
4772 /* we are good with balance_ctl ripped off from under us */
4773 BUG_ON(test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4774 atomic_dec(&fs_info->balance_pause_req);
4775 } else {
4776 ret = -ENOTCONN;
4777 }
4778
4779 mutex_unlock(&fs_info->balance_mutex);
4780 return ret;
4781 }
4782
btrfs_cancel_balance(struct btrfs_fs_info * fs_info)4783 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
4784 {
4785 mutex_lock(&fs_info->balance_mutex);
4786 if (!fs_info->balance_ctl) {
4787 mutex_unlock(&fs_info->balance_mutex);
4788 return -ENOTCONN;
4789 }
4790
4791 /*
4792 * A paused balance with the item stored on disk can be resumed at
4793 * mount time if the mount is read-write. Otherwise it's still paused
4794 * and we must not allow cancelling as it deletes the item.
4795 */
4796 if (sb_rdonly(fs_info->sb)) {
4797 mutex_unlock(&fs_info->balance_mutex);
4798 return -EROFS;
4799 }
4800
4801 atomic_inc(&fs_info->balance_cancel_req);
4802 /*
4803 * if we are running just wait and return, balance item is
4804 * deleted in btrfs_balance in this case
4805 */
4806 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4807 mutex_unlock(&fs_info->balance_mutex);
4808 wait_event(fs_info->balance_wait_q,
4809 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4810 mutex_lock(&fs_info->balance_mutex);
4811 } else {
4812 mutex_unlock(&fs_info->balance_mutex);
4813 /*
4814 * Lock released to allow other waiters to continue, we'll
4815 * reexamine the status again.
4816 */
4817 mutex_lock(&fs_info->balance_mutex);
4818
4819 if (fs_info->balance_ctl) {
4820 reset_balance_state(fs_info);
4821 btrfs_exclop_finish(fs_info);
4822 btrfs_info(fs_info, "balance: canceled");
4823 }
4824 }
4825
4826 ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags));
4827 atomic_dec(&fs_info->balance_cancel_req);
4828 mutex_unlock(&fs_info->balance_mutex);
4829 return 0;
4830 }
4831
4832 /*
4833 * shrinking a device means finding all of the device extents past
4834 * the new size, and then following the back refs to the chunks.
4835 * The chunk relocation code actually frees the device extent
4836 */
btrfs_shrink_device(struct btrfs_device * device,u64 new_size)4837 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
4838 {
4839 struct btrfs_fs_info *fs_info = device->fs_info;
4840 struct btrfs_root *root = fs_info->dev_root;
4841 struct btrfs_trans_handle *trans;
4842 struct btrfs_dev_extent *dev_extent = NULL;
4843 struct btrfs_path *path;
4844 u64 length;
4845 u64 chunk_offset;
4846 int ret;
4847 int slot;
4848 int failed = 0;
4849 bool retried = false;
4850 struct extent_buffer *l;
4851 struct btrfs_key key;
4852 struct btrfs_super_block *super_copy = fs_info->super_copy;
4853 u64 old_total = btrfs_super_total_bytes(super_copy);
4854 u64 old_size = btrfs_device_get_total_bytes(device);
4855 u64 diff;
4856 u64 start;
4857 u64 free_diff = 0;
4858
4859 new_size = round_down(new_size, fs_info->sectorsize);
4860 start = new_size;
4861 diff = round_down(old_size - new_size, fs_info->sectorsize);
4862
4863 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
4864 return -EINVAL;
4865
4866 path = btrfs_alloc_path();
4867 if (!path)
4868 return -ENOMEM;
4869
4870 path->reada = READA_BACK;
4871
4872 trans = btrfs_start_transaction(root, 0);
4873 if (IS_ERR(trans)) {
4874 btrfs_free_path(path);
4875 return PTR_ERR(trans);
4876 }
4877
4878 mutex_lock(&fs_info->chunk_mutex);
4879
4880 btrfs_device_set_total_bytes(device, new_size);
4881 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
4882 device->fs_devices->total_rw_bytes -= diff;
4883
4884 /*
4885 * The new free_chunk_space is new_size - used, so we have to
4886 * subtract the delta of the old free_chunk_space which included
4887 * old_size - used. If used > new_size then just subtract this
4888 * entire device's free space.
4889 */
4890 if (device->bytes_used < new_size)
4891 free_diff = (old_size - device->bytes_used) -
4892 (new_size - device->bytes_used);
4893 else
4894 free_diff = old_size - device->bytes_used;
4895 atomic64_sub(free_diff, &fs_info->free_chunk_space);
4896 }
4897
4898 /*
4899 * Once the device's size has been set to the new size, ensure all
4900 * in-memory chunks are synced to disk so that the loop below sees them
4901 * and relocates them accordingly.
4902 */
4903 if (contains_pending_extent(device, &start, diff)) {
4904 mutex_unlock(&fs_info->chunk_mutex);
4905 ret = btrfs_commit_transaction(trans);
4906 if (ret)
4907 goto done;
4908 } else {
4909 mutex_unlock(&fs_info->chunk_mutex);
4910 btrfs_end_transaction(trans);
4911 }
4912
4913 again:
4914 key.objectid = device->devid;
4915 key.type = BTRFS_DEV_EXTENT_KEY;
4916 key.offset = (u64)-1;
4917
4918 do {
4919 mutex_lock(&fs_info->reclaim_bgs_lock);
4920 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4921 if (ret < 0) {
4922 mutex_unlock(&fs_info->reclaim_bgs_lock);
4923 goto done;
4924 }
4925
4926 ret = btrfs_previous_item(root, path, 0, key.type);
4927 if (ret) {
4928 mutex_unlock(&fs_info->reclaim_bgs_lock);
4929 if (ret < 0)
4930 goto done;
4931 ret = 0;
4932 btrfs_release_path(path);
4933 break;
4934 }
4935
4936 l = path->nodes[0];
4937 slot = path->slots[0];
4938 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
4939
4940 if (key.objectid != device->devid) {
4941 mutex_unlock(&fs_info->reclaim_bgs_lock);
4942 btrfs_release_path(path);
4943 break;
4944 }
4945
4946 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
4947 length = btrfs_dev_extent_length(l, dev_extent);
4948
4949 if (key.offset + length <= new_size) {
4950 mutex_unlock(&fs_info->reclaim_bgs_lock);
4951 btrfs_release_path(path);
4952 break;
4953 }
4954
4955 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
4956 btrfs_release_path(path);
4957
4958 /*
4959 * We may be relocating the only data chunk we have,
4960 * which could potentially end up with losing data's
4961 * raid profile, so lets allocate an empty one in
4962 * advance.
4963 */
4964 ret = btrfs_may_alloc_data_chunk(fs_info, chunk_offset);
4965 if (ret < 0) {
4966 mutex_unlock(&fs_info->reclaim_bgs_lock);
4967 goto done;
4968 }
4969
4970 ret = btrfs_relocate_chunk(fs_info, chunk_offset);
4971 mutex_unlock(&fs_info->reclaim_bgs_lock);
4972 if (ret == -ENOSPC) {
4973 failed++;
4974 } else if (ret) {
4975 if (ret == -ETXTBSY) {
4976 btrfs_warn(fs_info,
4977 "could not shrink block group %llu due to active swapfile",
4978 chunk_offset);
4979 }
4980 goto done;
4981 }
4982 } while (key.offset-- > 0);
4983
4984 if (failed && !retried) {
4985 failed = 0;
4986 retried = true;
4987 goto again;
4988 } else if (failed && retried) {
4989 ret = -ENOSPC;
4990 goto done;
4991 }
4992
4993 /* Shrinking succeeded, else we would be at "done". */
4994 trans = btrfs_start_transaction(root, 0);
4995 if (IS_ERR(trans)) {
4996 ret = PTR_ERR(trans);
4997 goto done;
4998 }
4999
5000 mutex_lock(&fs_info->chunk_mutex);
5001 /* Clear all state bits beyond the shrunk device size */
5002 clear_extent_bits(&device->alloc_state, new_size, (u64)-1,
5003 CHUNK_STATE_MASK);
5004
5005 btrfs_device_set_disk_total_bytes(device, new_size);
5006 if (list_empty(&device->post_commit_list))
5007 list_add_tail(&device->post_commit_list,
5008 &trans->transaction->dev_update_list);
5009
5010 WARN_ON(diff > old_total);
5011 btrfs_set_super_total_bytes(super_copy,
5012 round_down(old_total - diff, fs_info->sectorsize));
5013 mutex_unlock(&fs_info->chunk_mutex);
5014
5015 btrfs_reserve_chunk_metadata(trans, false);
5016 /* Now btrfs_update_device() will change the on-disk size. */
5017 ret = btrfs_update_device(trans, device);
5018 btrfs_trans_release_chunk_metadata(trans);
5019 if (ret < 0) {
5020 btrfs_abort_transaction(trans, ret);
5021 btrfs_end_transaction(trans);
5022 } else {
5023 ret = btrfs_commit_transaction(trans);
5024 }
5025 done:
5026 btrfs_free_path(path);
5027 if (ret) {
5028 mutex_lock(&fs_info->chunk_mutex);
5029 btrfs_device_set_total_bytes(device, old_size);
5030 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
5031 device->fs_devices->total_rw_bytes += diff;
5032 atomic64_add(free_diff, &fs_info->free_chunk_space);
5033 }
5034 mutex_unlock(&fs_info->chunk_mutex);
5035 }
5036 return ret;
5037 }
5038
btrfs_add_system_chunk(struct btrfs_fs_info * fs_info,struct btrfs_key * key,struct btrfs_chunk * chunk,int item_size)5039 static int btrfs_add_system_chunk(struct btrfs_fs_info *fs_info,
5040 struct btrfs_key *key,
5041 struct btrfs_chunk *chunk, int item_size)
5042 {
5043 struct btrfs_super_block *super_copy = fs_info->super_copy;
5044 struct btrfs_disk_key disk_key;
5045 u32 array_size;
5046 u8 *ptr;
5047
5048 lockdep_assert_held(&fs_info->chunk_mutex);
5049
5050 array_size = btrfs_super_sys_array_size(super_copy);
5051 if (array_size + item_size + sizeof(disk_key)
5052 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
5053 return -EFBIG;
5054
5055 ptr = super_copy->sys_chunk_array + array_size;
5056 btrfs_cpu_key_to_disk(&disk_key, key);
5057 memcpy(ptr, &disk_key, sizeof(disk_key));
5058 ptr += sizeof(disk_key);
5059 memcpy(ptr, chunk, item_size);
5060 item_size += sizeof(disk_key);
5061 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
5062
5063 return 0;
5064 }
5065
5066 /*
5067 * sort the devices in descending order by max_avail, total_avail
5068 */
btrfs_cmp_device_info(const void * a,const void * b)5069 static int btrfs_cmp_device_info(const void *a, const void *b)
5070 {
5071 const struct btrfs_device_info *di_a = a;
5072 const struct btrfs_device_info *di_b = b;
5073
5074 if (di_a->max_avail > di_b->max_avail)
5075 return -1;
5076 if (di_a->max_avail < di_b->max_avail)
5077 return 1;
5078 if (di_a->total_avail > di_b->total_avail)
5079 return -1;
5080 if (di_a->total_avail < di_b->total_avail)
5081 return 1;
5082 return 0;
5083 }
5084
check_raid56_incompat_flag(struct btrfs_fs_info * info,u64 type)5085 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
5086 {
5087 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
5088 return;
5089
5090 btrfs_set_fs_incompat(info, RAID56);
5091 }
5092
check_raid1c34_incompat_flag(struct btrfs_fs_info * info,u64 type)5093 static void check_raid1c34_incompat_flag(struct btrfs_fs_info *info, u64 type)
5094 {
5095 if (!(type & (BTRFS_BLOCK_GROUP_RAID1C3 | BTRFS_BLOCK_GROUP_RAID1C4)))
5096 return;
5097
5098 btrfs_set_fs_incompat(info, RAID1C34);
5099 }
5100
5101 /*
5102 * Structure used internally for btrfs_create_chunk() function.
5103 * Wraps needed parameters.
5104 */
5105 struct alloc_chunk_ctl {
5106 u64 start;
5107 u64 type;
5108 /* Total number of stripes to allocate */
5109 int num_stripes;
5110 /* sub_stripes info for map */
5111 int sub_stripes;
5112 /* Stripes per device */
5113 int dev_stripes;
5114 /* Maximum number of devices to use */
5115 int devs_max;
5116 /* Minimum number of devices to use */
5117 int devs_min;
5118 /* ndevs has to be a multiple of this */
5119 int devs_increment;
5120 /* Number of copies */
5121 int ncopies;
5122 /* Number of stripes worth of bytes to store parity information */
5123 int nparity;
5124 u64 max_stripe_size;
5125 u64 max_chunk_size;
5126 u64 dev_extent_min;
5127 u64 stripe_size;
5128 u64 chunk_size;
5129 int ndevs;
5130 };
5131
init_alloc_chunk_ctl_policy_regular(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl)5132 static void init_alloc_chunk_ctl_policy_regular(
5133 struct btrfs_fs_devices *fs_devices,
5134 struct alloc_chunk_ctl *ctl)
5135 {
5136 struct btrfs_space_info *space_info;
5137
5138 space_info = btrfs_find_space_info(fs_devices->fs_info, ctl->type);
5139 ASSERT(space_info);
5140
5141 ctl->max_chunk_size = READ_ONCE(space_info->chunk_size);
5142 ctl->max_stripe_size = min_t(u64, ctl->max_chunk_size, SZ_1G);
5143
5144 if (ctl->type & BTRFS_BLOCK_GROUP_SYSTEM)
5145 ctl->devs_max = min_t(int, ctl->devs_max, BTRFS_MAX_DEVS_SYS_CHUNK);
5146
5147 /* We don't want a chunk larger than 10% of writable space */
5148 ctl->max_chunk_size = min(mult_perc(fs_devices->total_rw_bytes, 10),
5149 ctl->max_chunk_size);
5150 ctl->dev_extent_min = btrfs_stripe_nr_to_offset(ctl->dev_stripes);
5151 }
5152
init_alloc_chunk_ctl_policy_zoned(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl)5153 static void init_alloc_chunk_ctl_policy_zoned(
5154 struct btrfs_fs_devices *fs_devices,
5155 struct alloc_chunk_ctl *ctl)
5156 {
5157 u64 zone_size = fs_devices->fs_info->zone_size;
5158 u64 limit;
5159 int min_num_stripes = ctl->devs_min * ctl->dev_stripes;
5160 int min_data_stripes = (min_num_stripes - ctl->nparity) / ctl->ncopies;
5161 u64 min_chunk_size = min_data_stripes * zone_size;
5162 u64 type = ctl->type;
5163
5164 ctl->max_stripe_size = zone_size;
5165 if (type & BTRFS_BLOCK_GROUP_DATA) {
5166 ctl->max_chunk_size = round_down(BTRFS_MAX_DATA_CHUNK_SIZE,
5167 zone_size);
5168 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
5169 ctl->max_chunk_size = ctl->max_stripe_size;
5170 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
5171 ctl->max_chunk_size = 2 * ctl->max_stripe_size;
5172 ctl->devs_max = min_t(int, ctl->devs_max,
5173 BTRFS_MAX_DEVS_SYS_CHUNK);
5174 } else {
5175 BUG();
5176 }
5177
5178 /* We don't want a chunk larger than 10% of writable space */
5179 limit = max(round_down(mult_perc(fs_devices->total_rw_bytes, 10),
5180 zone_size),
5181 min_chunk_size);
5182 ctl->max_chunk_size = min(limit, ctl->max_chunk_size);
5183 ctl->dev_extent_min = zone_size * ctl->dev_stripes;
5184 }
5185
init_alloc_chunk_ctl(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl)5186 static void init_alloc_chunk_ctl(struct btrfs_fs_devices *fs_devices,
5187 struct alloc_chunk_ctl *ctl)
5188 {
5189 int index = btrfs_bg_flags_to_raid_index(ctl->type);
5190
5191 ctl->sub_stripes = btrfs_raid_array[index].sub_stripes;
5192 ctl->dev_stripes = btrfs_raid_array[index].dev_stripes;
5193 ctl->devs_max = btrfs_raid_array[index].devs_max;
5194 if (!ctl->devs_max)
5195 ctl->devs_max = BTRFS_MAX_DEVS(fs_devices->fs_info);
5196 ctl->devs_min = btrfs_raid_array[index].devs_min;
5197 ctl->devs_increment = btrfs_raid_array[index].devs_increment;
5198 ctl->ncopies = btrfs_raid_array[index].ncopies;
5199 ctl->nparity = btrfs_raid_array[index].nparity;
5200 ctl->ndevs = 0;
5201
5202 switch (fs_devices->chunk_alloc_policy) {
5203 case BTRFS_CHUNK_ALLOC_REGULAR:
5204 init_alloc_chunk_ctl_policy_regular(fs_devices, ctl);
5205 break;
5206 case BTRFS_CHUNK_ALLOC_ZONED:
5207 init_alloc_chunk_ctl_policy_zoned(fs_devices, ctl);
5208 break;
5209 default:
5210 BUG();
5211 }
5212 }
5213
gather_device_info(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5214 static int gather_device_info(struct btrfs_fs_devices *fs_devices,
5215 struct alloc_chunk_ctl *ctl,
5216 struct btrfs_device_info *devices_info)
5217 {
5218 struct btrfs_fs_info *info = fs_devices->fs_info;
5219 struct btrfs_device *device;
5220 u64 total_avail;
5221 u64 dev_extent_want = ctl->max_stripe_size * ctl->dev_stripes;
5222 int ret;
5223 int ndevs = 0;
5224 u64 max_avail;
5225 u64 dev_offset;
5226
5227 /*
5228 * in the first pass through the devices list, we gather information
5229 * about the available holes on each device.
5230 */
5231 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
5232 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
5233 WARN(1, KERN_ERR
5234 "BTRFS: read-only device in alloc_list\n");
5235 continue;
5236 }
5237
5238 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
5239 &device->dev_state) ||
5240 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
5241 continue;
5242
5243 if (device->total_bytes > device->bytes_used)
5244 total_avail = device->total_bytes - device->bytes_used;
5245 else
5246 total_avail = 0;
5247
5248 /* If there is no space on this device, skip it. */
5249 if (total_avail < ctl->dev_extent_min)
5250 continue;
5251
5252 ret = find_free_dev_extent(device, dev_extent_want, &dev_offset,
5253 &max_avail);
5254 if (ret && ret != -ENOSPC)
5255 return ret;
5256
5257 if (ret == 0)
5258 max_avail = dev_extent_want;
5259
5260 if (max_avail < ctl->dev_extent_min) {
5261 if (btrfs_test_opt(info, ENOSPC_DEBUG))
5262 btrfs_debug(info,
5263 "%s: devid %llu has no free space, have=%llu want=%llu",
5264 __func__, device->devid, max_avail,
5265 ctl->dev_extent_min);
5266 continue;
5267 }
5268
5269 if (ndevs == fs_devices->rw_devices) {
5270 WARN(1, "%s: found more than %llu devices\n",
5271 __func__, fs_devices->rw_devices);
5272 break;
5273 }
5274 devices_info[ndevs].dev_offset = dev_offset;
5275 devices_info[ndevs].max_avail = max_avail;
5276 devices_info[ndevs].total_avail = total_avail;
5277 devices_info[ndevs].dev = device;
5278 ++ndevs;
5279 }
5280 ctl->ndevs = ndevs;
5281
5282 /*
5283 * now sort the devices by hole size / available space
5284 */
5285 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
5286 btrfs_cmp_device_info, NULL);
5287
5288 return 0;
5289 }
5290
decide_stripe_size_regular(struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5291 static int decide_stripe_size_regular(struct alloc_chunk_ctl *ctl,
5292 struct btrfs_device_info *devices_info)
5293 {
5294 /* Number of stripes that count for block group size */
5295 int data_stripes;
5296
5297 /*
5298 * The primary goal is to maximize the number of stripes, so use as
5299 * many devices as possible, even if the stripes are not maximum sized.
5300 *
5301 * The DUP profile stores more than one stripe per device, the
5302 * max_avail is the total size so we have to adjust.
5303 */
5304 ctl->stripe_size = div_u64(devices_info[ctl->ndevs - 1].max_avail,
5305 ctl->dev_stripes);
5306 ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
5307
5308 /* This will have to be fixed for RAID1 and RAID10 over more drives */
5309 data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
5310
5311 /*
5312 * Use the number of data stripes to figure out how big this chunk is
5313 * really going to be in terms of logical address space, and compare
5314 * that answer with the max chunk size. If it's higher, we try to
5315 * reduce stripe_size.
5316 */
5317 if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
5318 /*
5319 * Reduce stripe_size, round it up to a 16MB boundary again and
5320 * then use it, unless it ends up being even bigger than the
5321 * previous value we had already.
5322 */
5323 ctl->stripe_size = min(round_up(div_u64(ctl->max_chunk_size,
5324 data_stripes), SZ_16M),
5325 ctl->stripe_size);
5326 }
5327
5328 /* Stripe size should not go beyond 1G. */
5329 ctl->stripe_size = min_t(u64, ctl->stripe_size, SZ_1G);
5330
5331 /* Align to BTRFS_STRIPE_LEN */
5332 ctl->stripe_size = round_down(ctl->stripe_size, BTRFS_STRIPE_LEN);
5333 ctl->chunk_size = ctl->stripe_size * data_stripes;
5334
5335 return 0;
5336 }
5337
decide_stripe_size_zoned(struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5338 static int decide_stripe_size_zoned(struct alloc_chunk_ctl *ctl,
5339 struct btrfs_device_info *devices_info)
5340 {
5341 u64 zone_size = devices_info[0].dev->zone_info->zone_size;
5342 /* Number of stripes that count for block group size */
5343 int data_stripes;
5344
5345 /*
5346 * It should hold because:
5347 * dev_extent_min == dev_extent_want == zone_size * dev_stripes
5348 */
5349 ASSERT(devices_info[ctl->ndevs - 1].max_avail == ctl->dev_extent_min);
5350
5351 ctl->stripe_size = zone_size;
5352 ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
5353 data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
5354
5355 /* stripe_size is fixed in zoned filesystem. Reduce ndevs instead. */
5356 if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) {
5357 ctl->ndevs = div_u64(div_u64(ctl->max_chunk_size * ctl->ncopies,
5358 ctl->stripe_size) + ctl->nparity,
5359 ctl->dev_stripes);
5360 ctl->num_stripes = ctl->ndevs * ctl->dev_stripes;
5361 data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies;
5362 ASSERT(ctl->stripe_size * data_stripes <= ctl->max_chunk_size);
5363 }
5364
5365 ctl->chunk_size = ctl->stripe_size * data_stripes;
5366
5367 return 0;
5368 }
5369
decide_stripe_size(struct btrfs_fs_devices * fs_devices,struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5370 static int decide_stripe_size(struct btrfs_fs_devices *fs_devices,
5371 struct alloc_chunk_ctl *ctl,
5372 struct btrfs_device_info *devices_info)
5373 {
5374 struct btrfs_fs_info *info = fs_devices->fs_info;
5375
5376 /*
5377 * Round down to number of usable stripes, devs_increment can be any
5378 * number so we can't use round_down() that requires power of 2, while
5379 * rounddown is safe.
5380 */
5381 ctl->ndevs = rounddown(ctl->ndevs, ctl->devs_increment);
5382
5383 if (ctl->ndevs < ctl->devs_min) {
5384 if (btrfs_test_opt(info, ENOSPC_DEBUG)) {
5385 btrfs_debug(info,
5386 "%s: not enough devices with free space: have=%d minimum required=%d",
5387 __func__, ctl->ndevs, ctl->devs_min);
5388 }
5389 return -ENOSPC;
5390 }
5391
5392 ctl->ndevs = min(ctl->ndevs, ctl->devs_max);
5393
5394 switch (fs_devices->chunk_alloc_policy) {
5395 case BTRFS_CHUNK_ALLOC_REGULAR:
5396 return decide_stripe_size_regular(ctl, devices_info);
5397 case BTRFS_CHUNK_ALLOC_ZONED:
5398 return decide_stripe_size_zoned(ctl, devices_info);
5399 default:
5400 BUG();
5401 }
5402 }
5403
chunk_map_device_set_bits(struct btrfs_chunk_map * map,unsigned int bits)5404 static void chunk_map_device_set_bits(struct btrfs_chunk_map *map, unsigned int bits)
5405 {
5406 for (int i = 0; i < map->num_stripes; i++) {
5407 struct btrfs_io_stripe *stripe = &map->stripes[i];
5408 struct btrfs_device *device = stripe->dev;
5409
5410 set_extent_bit(&device->alloc_state, stripe->physical,
5411 stripe->physical + map->stripe_size - 1,
5412 bits | EXTENT_NOWAIT, NULL);
5413 }
5414 }
5415
chunk_map_device_clear_bits(struct btrfs_chunk_map * map,unsigned int bits)5416 static void chunk_map_device_clear_bits(struct btrfs_chunk_map *map, unsigned int bits)
5417 {
5418 for (int i = 0; i < map->num_stripes; i++) {
5419 struct btrfs_io_stripe *stripe = &map->stripes[i];
5420 struct btrfs_device *device = stripe->dev;
5421
5422 __clear_extent_bit(&device->alloc_state, stripe->physical,
5423 stripe->physical + map->stripe_size - 1,
5424 bits | EXTENT_NOWAIT,
5425 NULL, NULL);
5426 }
5427 }
5428
btrfs_remove_chunk_map(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map)5429 void btrfs_remove_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map)
5430 {
5431 write_lock(&fs_info->mapping_tree_lock);
5432 rb_erase_cached(&map->rb_node, &fs_info->mapping_tree);
5433 RB_CLEAR_NODE(&map->rb_node);
5434 chunk_map_device_clear_bits(map, CHUNK_ALLOCATED);
5435 write_unlock(&fs_info->mapping_tree_lock);
5436
5437 /* Once for the tree reference. */
5438 btrfs_free_chunk_map(map);
5439 }
5440
btrfs_chunk_map_cmp(const struct rb_node * new,const struct rb_node * exist)5441 static int btrfs_chunk_map_cmp(const struct rb_node *new,
5442 const struct rb_node *exist)
5443 {
5444 const struct btrfs_chunk_map *new_map =
5445 rb_entry(new, struct btrfs_chunk_map, rb_node);
5446 const struct btrfs_chunk_map *exist_map =
5447 rb_entry(exist, struct btrfs_chunk_map, rb_node);
5448
5449 if (new_map->start == exist_map->start)
5450 return 0;
5451 if (new_map->start < exist_map->start)
5452 return -1;
5453 return 1;
5454 }
5455
5456 EXPORT_FOR_TESTS
btrfs_add_chunk_map(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map)5457 int btrfs_add_chunk_map(struct btrfs_fs_info *fs_info, struct btrfs_chunk_map *map)
5458 {
5459 struct rb_node *exist;
5460
5461 write_lock(&fs_info->mapping_tree_lock);
5462 exist = rb_find_add_cached(&map->rb_node, &fs_info->mapping_tree,
5463 btrfs_chunk_map_cmp);
5464
5465 if (exist) {
5466 write_unlock(&fs_info->mapping_tree_lock);
5467 return -EEXIST;
5468 }
5469 chunk_map_device_set_bits(map, CHUNK_ALLOCATED);
5470 chunk_map_device_clear_bits(map, CHUNK_TRIMMED);
5471 write_unlock(&fs_info->mapping_tree_lock);
5472
5473 return 0;
5474 }
5475
5476 EXPORT_FOR_TESTS
btrfs_alloc_chunk_map(int num_stripes,gfp_t gfp)5477 struct btrfs_chunk_map *btrfs_alloc_chunk_map(int num_stripes, gfp_t gfp)
5478 {
5479 struct btrfs_chunk_map *map;
5480
5481 map = kmalloc(btrfs_chunk_map_size(num_stripes), gfp);
5482 if (!map)
5483 return NULL;
5484
5485 refcount_set(&map->refs, 1);
5486 RB_CLEAR_NODE(&map->rb_node);
5487
5488 return map;
5489 }
5490
create_chunk(struct btrfs_trans_handle * trans,struct alloc_chunk_ctl * ctl,struct btrfs_device_info * devices_info)5491 static struct btrfs_block_group *create_chunk(struct btrfs_trans_handle *trans,
5492 struct alloc_chunk_ctl *ctl,
5493 struct btrfs_device_info *devices_info)
5494 {
5495 struct btrfs_fs_info *info = trans->fs_info;
5496 struct btrfs_chunk_map *map;
5497 struct btrfs_block_group *block_group;
5498 u64 start = ctl->start;
5499 u64 type = ctl->type;
5500 int ret;
5501
5502 map = btrfs_alloc_chunk_map(ctl->num_stripes, GFP_NOFS);
5503 if (!map)
5504 return ERR_PTR(-ENOMEM);
5505
5506 map->start = start;
5507 map->chunk_len = ctl->chunk_size;
5508 map->stripe_size = ctl->stripe_size;
5509 map->type = type;
5510 map->io_align = BTRFS_STRIPE_LEN;
5511 map->io_width = BTRFS_STRIPE_LEN;
5512 map->sub_stripes = ctl->sub_stripes;
5513 map->num_stripes = ctl->num_stripes;
5514
5515 for (int i = 0; i < ctl->ndevs; i++) {
5516 for (int j = 0; j < ctl->dev_stripes; j++) {
5517 int s = i * ctl->dev_stripes + j;
5518 map->stripes[s].dev = devices_info[i].dev;
5519 map->stripes[s].physical = devices_info[i].dev_offset +
5520 j * ctl->stripe_size;
5521 }
5522 }
5523
5524 trace_btrfs_chunk_alloc(info, map, start, ctl->chunk_size);
5525
5526 ret = btrfs_add_chunk_map(info, map);
5527 if (ret) {
5528 btrfs_free_chunk_map(map);
5529 return ERR_PTR(ret);
5530 }
5531
5532 block_group = btrfs_make_block_group(trans, type, start, ctl->chunk_size);
5533 if (IS_ERR(block_group)) {
5534 btrfs_remove_chunk_map(info, map);
5535 return block_group;
5536 }
5537
5538 for (int i = 0; i < map->num_stripes; i++) {
5539 struct btrfs_device *dev = map->stripes[i].dev;
5540
5541 btrfs_device_set_bytes_used(dev,
5542 dev->bytes_used + ctl->stripe_size);
5543 if (list_empty(&dev->post_commit_list))
5544 list_add_tail(&dev->post_commit_list,
5545 &trans->transaction->dev_update_list);
5546 }
5547
5548 atomic64_sub(ctl->stripe_size * map->num_stripes,
5549 &info->free_chunk_space);
5550
5551 check_raid56_incompat_flag(info, type);
5552 check_raid1c34_incompat_flag(info, type);
5553
5554 return block_group;
5555 }
5556
btrfs_create_chunk(struct btrfs_trans_handle * trans,u64 type)5557 struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans,
5558 u64 type)
5559 {
5560 struct btrfs_fs_info *info = trans->fs_info;
5561 struct btrfs_fs_devices *fs_devices = info->fs_devices;
5562 struct btrfs_device_info *devices_info = NULL;
5563 struct alloc_chunk_ctl ctl;
5564 struct btrfs_block_group *block_group;
5565 int ret;
5566
5567 lockdep_assert_held(&info->chunk_mutex);
5568
5569 if (!alloc_profile_is_valid(type, 0)) {
5570 ASSERT(0);
5571 return ERR_PTR(-EINVAL);
5572 }
5573
5574 if (list_empty(&fs_devices->alloc_list)) {
5575 if (btrfs_test_opt(info, ENOSPC_DEBUG))
5576 btrfs_debug(info, "%s: no writable device", __func__);
5577 return ERR_PTR(-ENOSPC);
5578 }
5579
5580 if (!(type & BTRFS_BLOCK_GROUP_TYPE_MASK)) {
5581 btrfs_err(info, "invalid chunk type 0x%llx requested", type);
5582 ASSERT(0);
5583 return ERR_PTR(-EINVAL);
5584 }
5585
5586 ctl.start = find_next_chunk(info);
5587 ctl.type = type;
5588 init_alloc_chunk_ctl(fs_devices, &ctl);
5589
5590 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
5591 GFP_NOFS);
5592 if (!devices_info)
5593 return ERR_PTR(-ENOMEM);
5594
5595 ret = gather_device_info(fs_devices, &ctl, devices_info);
5596 if (ret < 0) {
5597 block_group = ERR_PTR(ret);
5598 goto out;
5599 }
5600
5601 ret = decide_stripe_size(fs_devices, &ctl, devices_info);
5602 if (ret < 0) {
5603 block_group = ERR_PTR(ret);
5604 goto out;
5605 }
5606
5607 block_group = create_chunk(trans, &ctl, devices_info);
5608
5609 out:
5610 kfree(devices_info);
5611 return block_group;
5612 }
5613
5614 /*
5615 * This function, btrfs_chunk_alloc_add_chunk_item(), typically belongs to the
5616 * phase 1 of chunk allocation. It belongs to phase 2 only when allocating system
5617 * chunks.
5618 *
5619 * See the comment at btrfs_chunk_alloc() for details about the chunk allocation
5620 * phases.
5621 */
btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle * trans,struct btrfs_block_group * bg)5622 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
5623 struct btrfs_block_group *bg)
5624 {
5625 struct btrfs_fs_info *fs_info = trans->fs_info;
5626 struct btrfs_root *chunk_root = fs_info->chunk_root;
5627 struct btrfs_key key;
5628 struct btrfs_chunk *chunk;
5629 struct btrfs_stripe *stripe;
5630 struct btrfs_chunk_map *map;
5631 size_t item_size;
5632 int i;
5633 int ret;
5634
5635 /*
5636 * We take the chunk_mutex for 2 reasons:
5637 *
5638 * 1) Updates and insertions in the chunk btree must be done while holding
5639 * the chunk_mutex, as well as updating the system chunk array in the
5640 * superblock. See the comment on top of btrfs_chunk_alloc() for the
5641 * details;
5642 *
5643 * 2) To prevent races with the final phase of a device replace operation
5644 * that replaces the device object associated with the map's stripes,
5645 * because the device object's id can change at any time during that
5646 * final phase of the device replace operation
5647 * (dev-replace.c:btrfs_dev_replace_finishing()), so we could grab the
5648 * replaced device and then see it with an ID of BTRFS_DEV_REPLACE_DEVID,
5649 * which would cause a failure when updating the device item, which does
5650 * not exists, or persisting a stripe of the chunk item with such ID.
5651 * Here we can't use the device_list_mutex because our caller already
5652 * has locked the chunk_mutex, and the final phase of device replace
5653 * acquires both mutexes - first the device_list_mutex and then the
5654 * chunk_mutex. Using any of those two mutexes protects us from a
5655 * concurrent device replace.
5656 */
5657 lockdep_assert_held(&fs_info->chunk_mutex);
5658
5659 map = btrfs_get_chunk_map(fs_info, bg->start, bg->length);
5660 if (IS_ERR(map)) {
5661 ret = PTR_ERR(map);
5662 btrfs_abort_transaction(trans, ret);
5663 return ret;
5664 }
5665
5666 item_size = btrfs_chunk_item_size(map->num_stripes);
5667
5668 chunk = kzalloc(item_size, GFP_NOFS);
5669 if (!chunk) {
5670 ret = -ENOMEM;
5671 btrfs_abort_transaction(trans, ret);
5672 goto out;
5673 }
5674
5675 for (i = 0; i < map->num_stripes; i++) {
5676 struct btrfs_device *device = map->stripes[i].dev;
5677
5678 ret = btrfs_update_device(trans, device);
5679 if (ret)
5680 goto out;
5681 }
5682
5683 stripe = &chunk->stripe;
5684 for (i = 0; i < map->num_stripes; i++) {
5685 struct btrfs_device *device = map->stripes[i].dev;
5686 const u64 dev_offset = map->stripes[i].physical;
5687
5688 btrfs_set_stack_stripe_devid(stripe, device->devid);
5689 btrfs_set_stack_stripe_offset(stripe, dev_offset);
5690 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
5691 stripe++;
5692 }
5693
5694 btrfs_set_stack_chunk_length(chunk, bg->length);
5695 btrfs_set_stack_chunk_owner(chunk, BTRFS_EXTENT_TREE_OBJECTID);
5696 btrfs_set_stack_chunk_stripe_len(chunk, BTRFS_STRIPE_LEN);
5697 btrfs_set_stack_chunk_type(chunk, map->type);
5698 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
5699 btrfs_set_stack_chunk_io_align(chunk, BTRFS_STRIPE_LEN);
5700 btrfs_set_stack_chunk_io_width(chunk, BTRFS_STRIPE_LEN);
5701 btrfs_set_stack_chunk_sector_size(chunk, fs_info->sectorsize);
5702 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
5703
5704 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
5705 key.type = BTRFS_CHUNK_ITEM_KEY;
5706 key.offset = bg->start;
5707
5708 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
5709 if (ret)
5710 goto out;
5711
5712 set_bit(BLOCK_GROUP_FLAG_CHUNK_ITEM_INSERTED, &bg->runtime_flags);
5713
5714 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
5715 ret = btrfs_add_system_chunk(fs_info, &key, chunk, item_size);
5716 if (ret)
5717 goto out;
5718 }
5719
5720 out:
5721 kfree(chunk);
5722 btrfs_free_chunk_map(map);
5723 return ret;
5724 }
5725
init_first_rw_device(struct btrfs_trans_handle * trans)5726 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans)
5727 {
5728 struct btrfs_fs_info *fs_info = trans->fs_info;
5729 u64 alloc_profile;
5730 struct btrfs_block_group *meta_bg;
5731 struct btrfs_block_group *sys_bg;
5732
5733 /*
5734 * When adding a new device for sprouting, the seed device is read-only
5735 * so we must first allocate a metadata and a system chunk. But before
5736 * adding the block group items to the extent, device and chunk btrees,
5737 * we must first:
5738 *
5739 * 1) Create both chunks without doing any changes to the btrees, as
5740 * otherwise we would get -ENOSPC since the block groups from the
5741 * seed device are read-only;
5742 *
5743 * 2) Add the device item for the new sprout device - finishing the setup
5744 * of a new block group requires updating the device item in the chunk
5745 * btree, so it must exist when we attempt to do it. The previous step
5746 * ensures this does not fail with -ENOSPC.
5747 *
5748 * After that we can add the block group items to their btrees:
5749 * update existing device item in the chunk btree, add a new block group
5750 * item to the extent btree, add a new chunk item to the chunk btree and
5751 * finally add the new device extent items to the devices btree.
5752 */
5753
5754 alloc_profile = btrfs_metadata_alloc_profile(fs_info);
5755 meta_bg = btrfs_create_chunk(trans, alloc_profile);
5756 if (IS_ERR(meta_bg))
5757 return PTR_ERR(meta_bg);
5758
5759 alloc_profile = btrfs_system_alloc_profile(fs_info);
5760 sys_bg = btrfs_create_chunk(trans, alloc_profile);
5761 if (IS_ERR(sys_bg))
5762 return PTR_ERR(sys_bg);
5763
5764 return 0;
5765 }
5766
btrfs_chunk_max_errors(struct btrfs_chunk_map * map)5767 static inline int btrfs_chunk_max_errors(struct btrfs_chunk_map *map)
5768 {
5769 const int index = btrfs_bg_flags_to_raid_index(map->type);
5770
5771 return btrfs_raid_array[index].tolerated_failures;
5772 }
5773
btrfs_chunk_writeable(struct btrfs_fs_info * fs_info,u64 chunk_offset)5774 bool btrfs_chunk_writeable(struct btrfs_fs_info *fs_info, u64 chunk_offset)
5775 {
5776 struct btrfs_chunk_map *map;
5777 int miss_ndevs = 0;
5778 int i;
5779 bool ret = true;
5780
5781 map = btrfs_get_chunk_map(fs_info, chunk_offset, 1);
5782 if (IS_ERR(map))
5783 return false;
5784
5785 for (i = 0; i < map->num_stripes; i++) {
5786 if (test_bit(BTRFS_DEV_STATE_MISSING,
5787 &map->stripes[i].dev->dev_state)) {
5788 miss_ndevs++;
5789 continue;
5790 }
5791 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE,
5792 &map->stripes[i].dev->dev_state)) {
5793 ret = false;
5794 goto end;
5795 }
5796 }
5797
5798 /*
5799 * If the number of missing devices is larger than max errors, we can
5800 * not write the data into that chunk successfully.
5801 */
5802 if (miss_ndevs > btrfs_chunk_max_errors(map))
5803 ret = false;
5804 end:
5805 btrfs_free_chunk_map(map);
5806 return ret;
5807 }
5808
btrfs_mapping_tree_free(struct btrfs_fs_info * fs_info)5809 void btrfs_mapping_tree_free(struct btrfs_fs_info *fs_info)
5810 {
5811 write_lock(&fs_info->mapping_tree_lock);
5812 while (!RB_EMPTY_ROOT(&fs_info->mapping_tree.rb_root)) {
5813 struct btrfs_chunk_map *map;
5814 struct rb_node *node;
5815
5816 node = rb_first_cached(&fs_info->mapping_tree);
5817 map = rb_entry(node, struct btrfs_chunk_map, rb_node);
5818 rb_erase_cached(&map->rb_node, &fs_info->mapping_tree);
5819 RB_CLEAR_NODE(&map->rb_node);
5820 chunk_map_device_clear_bits(map, CHUNK_ALLOCATED);
5821 /* Once for the tree ref. */
5822 btrfs_free_chunk_map(map);
5823 cond_resched_rwlock_write(&fs_info->mapping_tree_lock);
5824 }
5825 write_unlock(&fs_info->mapping_tree_lock);
5826 }
5827
btrfs_chunk_map_num_copies(const struct btrfs_chunk_map * map)5828 static int btrfs_chunk_map_num_copies(const struct btrfs_chunk_map *map)
5829 {
5830 enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(map->type);
5831
5832 if (map->type & BTRFS_BLOCK_GROUP_RAID5)
5833 return 2;
5834
5835 /*
5836 * There could be two corrupted data stripes, we need to loop retry in
5837 * order to rebuild the correct data.
5838 *
5839 * Fail a stripe at a time on every retry except the stripe under
5840 * reconstruction.
5841 */
5842 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5843 return map->num_stripes;
5844
5845 /* Non-RAID56, use their ncopies from btrfs_raid_array. */
5846 return btrfs_raid_array[index].ncopies;
5847 }
5848
btrfs_num_copies(struct btrfs_fs_info * fs_info,u64 logical,u64 len)5849 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
5850 {
5851 struct btrfs_chunk_map *map;
5852 int ret;
5853
5854 map = btrfs_get_chunk_map(fs_info, logical, len);
5855 if (IS_ERR(map))
5856 /*
5857 * We could return errors for these cases, but that could get
5858 * ugly and we'd probably do the same thing which is just not do
5859 * anything else and exit, so return 1 so the callers don't try
5860 * to use other copies.
5861 */
5862 return 1;
5863
5864 ret = btrfs_chunk_map_num_copies(map);
5865 btrfs_free_chunk_map(map);
5866 return ret;
5867 }
5868
btrfs_full_stripe_len(struct btrfs_fs_info * fs_info,u64 logical)5869 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
5870 u64 logical)
5871 {
5872 struct btrfs_chunk_map *map;
5873 unsigned long len = fs_info->sectorsize;
5874
5875 if (!btrfs_fs_incompat(fs_info, RAID56))
5876 return len;
5877
5878 map = btrfs_get_chunk_map(fs_info, logical, len);
5879
5880 if (!WARN_ON(IS_ERR(map))) {
5881 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
5882 len = btrfs_stripe_nr_to_offset(nr_data_stripes(map));
5883 btrfs_free_chunk_map(map);
5884 }
5885 return len;
5886 }
5887
5888 #ifdef CONFIG_BTRFS_EXPERIMENTAL
btrfs_read_preferred(struct btrfs_chunk_map * map,int first,int num_stripes)5889 static int btrfs_read_preferred(struct btrfs_chunk_map *map, int first, int num_stripes)
5890 {
5891 for (int index = first; index < first + num_stripes; index++) {
5892 const struct btrfs_device *device = map->stripes[index].dev;
5893
5894 if (device->devid == READ_ONCE(device->fs_devices->read_devid))
5895 return index;
5896 }
5897
5898 /* If no read-preferred device is set use the first stripe. */
5899 return first;
5900 }
5901
5902 struct stripe_mirror {
5903 u64 devid;
5904 int num;
5905 };
5906
btrfs_cmp_devid(const void * a,const void * b)5907 static int btrfs_cmp_devid(const void *a, const void *b)
5908 {
5909 const struct stripe_mirror *s1 = (const struct stripe_mirror *)a;
5910 const struct stripe_mirror *s2 = (const struct stripe_mirror *)b;
5911
5912 if (s1->devid < s2->devid)
5913 return -1;
5914 if (s1->devid > s2->devid)
5915 return 1;
5916 return 0;
5917 }
5918
5919 /*
5920 * Select a stripe for reading using the round-robin algorithm.
5921 *
5922 * 1. Compute the read cycle as the total sectors read divided by the minimum
5923 * sectors per device.
5924 * 2. Determine the stripe number for the current read by taking the modulus
5925 * of the read cycle with the total number of stripes:
5926 *
5927 * stripe index = (total sectors / min sectors per dev) % num stripes
5928 *
5929 * The calculated stripe index is then used to select the corresponding device
5930 * from the list of devices, which is ordered by devid.
5931 */
btrfs_read_rr(const struct btrfs_chunk_map * map,int first,int num_stripes)5932 static int btrfs_read_rr(const struct btrfs_chunk_map *map, int first, int num_stripes)
5933 {
5934 struct stripe_mirror stripes[BTRFS_RAID1_MAX_MIRRORS] = { 0 };
5935 struct btrfs_device *device = map->stripes[first].dev;
5936 struct btrfs_fs_info *fs_info = device->fs_devices->fs_info;
5937 unsigned int read_cycle;
5938 unsigned int total_reads;
5939 unsigned int min_reads_per_dev;
5940
5941 total_reads = percpu_counter_sum(&fs_info->stats_read_blocks);
5942 min_reads_per_dev = READ_ONCE(fs_info->fs_devices->rr_min_contig_read) >>
5943 fs_info->sectorsize_bits;
5944
5945 for (int index = 0, i = first; i < first + num_stripes; i++) {
5946 stripes[index].devid = map->stripes[i].dev->devid;
5947 stripes[index].num = i;
5948 index++;
5949 }
5950 sort(stripes, num_stripes, sizeof(struct stripe_mirror),
5951 btrfs_cmp_devid, NULL);
5952
5953 read_cycle = total_reads / min_reads_per_dev;
5954 return stripes[read_cycle % num_stripes].num;
5955 }
5956 #endif
5957
find_live_mirror(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map,int first,int dev_replace_is_ongoing)5958 static int find_live_mirror(struct btrfs_fs_info *fs_info,
5959 struct btrfs_chunk_map *map, int first,
5960 int dev_replace_is_ongoing)
5961 {
5962 const enum btrfs_read_policy policy = READ_ONCE(fs_info->fs_devices->read_policy);
5963 int i;
5964 int num_stripes;
5965 int preferred_mirror;
5966 int tolerance;
5967 struct btrfs_device *srcdev;
5968
5969 ASSERT((map->type &
5970 (BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10)));
5971
5972 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5973 num_stripes = map->sub_stripes;
5974 else
5975 num_stripes = map->num_stripes;
5976
5977 switch (policy) {
5978 default:
5979 /* Shouldn't happen, just warn and use pid instead of failing */
5980 btrfs_warn_rl(fs_info, "unknown read_policy type %u, reset to pid",
5981 policy);
5982 WRITE_ONCE(fs_info->fs_devices->read_policy, BTRFS_READ_POLICY_PID);
5983 fallthrough;
5984 case BTRFS_READ_POLICY_PID:
5985 preferred_mirror = first + (current->pid % num_stripes);
5986 break;
5987 #ifdef CONFIG_BTRFS_EXPERIMENTAL
5988 case BTRFS_READ_POLICY_RR:
5989 preferred_mirror = btrfs_read_rr(map, first, num_stripes);
5990 break;
5991 case BTRFS_READ_POLICY_DEVID:
5992 preferred_mirror = btrfs_read_preferred(map, first, num_stripes);
5993 break;
5994 #endif
5995 }
5996
5997 if (dev_replace_is_ongoing &&
5998 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
5999 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
6000 srcdev = fs_info->dev_replace.srcdev;
6001 else
6002 srcdev = NULL;
6003
6004 /*
6005 * try to avoid the drive that is the source drive for a
6006 * dev-replace procedure, only choose it if no other non-missing
6007 * mirror is available
6008 */
6009 for (tolerance = 0; tolerance < 2; tolerance++) {
6010 if (map->stripes[preferred_mirror].dev->bdev &&
6011 (tolerance || map->stripes[preferred_mirror].dev != srcdev))
6012 return preferred_mirror;
6013 for (i = first; i < first + num_stripes; i++) {
6014 if (map->stripes[i].dev->bdev &&
6015 (tolerance || map->stripes[i].dev != srcdev))
6016 return i;
6017 }
6018 }
6019
6020 /* we couldn't find one that doesn't fail. Just return something
6021 * and the io error handling code will clean up eventually
6022 */
6023 return preferred_mirror;
6024 }
6025
6026 EXPORT_FOR_TESTS
alloc_btrfs_io_context(struct btrfs_fs_info * fs_info,u64 logical,u16 total_stripes)6027 struct btrfs_io_context *alloc_btrfs_io_context(struct btrfs_fs_info *fs_info,
6028 u64 logical, u16 total_stripes)
6029 {
6030 struct btrfs_io_context *bioc;
6031
6032 bioc = kzalloc(
6033 /* The size of btrfs_io_context */
6034 sizeof(struct btrfs_io_context) +
6035 /* Plus the variable array for the stripes */
6036 sizeof(struct btrfs_io_stripe) * (total_stripes),
6037 GFP_NOFS);
6038
6039 if (!bioc)
6040 return NULL;
6041
6042 refcount_set(&bioc->refs, 1);
6043
6044 bioc->fs_info = fs_info;
6045 bioc->replace_stripe_src = -1;
6046 bioc->full_stripe_logical = (u64)-1;
6047 bioc->logical = logical;
6048
6049 return bioc;
6050 }
6051
btrfs_get_bioc(struct btrfs_io_context * bioc)6052 void btrfs_get_bioc(struct btrfs_io_context *bioc)
6053 {
6054 WARN_ON(!refcount_read(&bioc->refs));
6055 refcount_inc(&bioc->refs);
6056 }
6057
btrfs_put_bioc(struct btrfs_io_context * bioc)6058 void btrfs_put_bioc(struct btrfs_io_context *bioc)
6059 {
6060 if (!bioc)
6061 return;
6062 if (refcount_dec_and_test(&bioc->refs))
6063 kfree(bioc);
6064 }
6065
6066 /*
6067 * Please note that, discard won't be sent to target device of device
6068 * replace.
6069 */
btrfs_map_discard(struct btrfs_fs_info * fs_info,u64 logical,u64 * length_ret,u32 * num_stripes)6070 struct btrfs_discard_stripe *btrfs_map_discard(struct btrfs_fs_info *fs_info,
6071 u64 logical, u64 *length_ret,
6072 u32 *num_stripes)
6073 {
6074 struct btrfs_chunk_map *map;
6075 struct btrfs_discard_stripe *stripes;
6076 u64 length = *length_ret;
6077 u64 offset;
6078 u32 stripe_nr;
6079 u32 stripe_nr_end;
6080 u32 stripe_cnt;
6081 u64 stripe_end_offset;
6082 u64 stripe_offset;
6083 u32 stripe_index;
6084 u32 factor = 0;
6085 u32 sub_stripes = 0;
6086 u32 stripes_per_dev = 0;
6087 u32 remaining_stripes = 0;
6088 u32 last_stripe = 0;
6089 int ret;
6090 int i;
6091
6092 map = btrfs_get_chunk_map(fs_info, logical, length);
6093 if (IS_ERR(map))
6094 return ERR_CAST(map);
6095
6096 /* we don't discard raid56 yet */
6097 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
6098 ret = -EOPNOTSUPP;
6099 goto out_free_map;
6100 }
6101
6102 offset = logical - map->start;
6103 length = min_t(u64, map->start + map->chunk_len - logical, length);
6104 *length_ret = length;
6105
6106 /*
6107 * stripe_nr counts the total number of stripes we have to stride
6108 * to get to this block
6109 */
6110 stripe_nr = offset >> BTRFS_STRIPE_LEN_SHIFT;
6111
6112 /* stripe_offset is the offset of this block in its stripe */
6113 stripe_offset = offset - btrfs_stripe_nr_to_offset(stripe_nr);
6114
6115 stripe_nr_end = round_up(offset + length, BTRFS_STRIPE_LEN) >>
6116 BTRFS_STRIPE_LEN_SHIFT;
6117 stripe_cnt = stripe_nr_end - stripe_nr;
6118 stripe_end_offset = btrfs_stripe_nr_to_offset(stripe_nr_end) -
6119 (offset + length);
6120 /*
6121 * after this, stripe_nr is the number of stripes on this
6122 * device we have to walk to find the data, and stripe_index is
6123 * the number of our device in the stripe array
6124 */
6125 *num_stripes = 1;
6126 stripe_index = 0;
6127 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
6128 BTRFS_BLOCK_GROUP_RAID10)) {
6129 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
6130 sub_stripes = 1;
6131 else
6132 sub_stripes = map->sub_stripes;
6133
6134 factor = map->num_stripes / sub_stripes;
6135 *num_stripes = min_t(u64, map->num_stripes,
6136 sub_stripes * stripe_cnt);
6137 stripe_index = stripe_nr % factor;
6138 stripe_nr /= factor;
6139 stripe_index *= sub_stripes;
6140
6141 remaining_stripes = stripe_cnt % factor;
6142 stripes_per_dev = stripe_cnt / factor;
6143 last_stripe = ((stripe_nr_end - 1) % factor) * sub_stripes;
6144 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID1_MASK |
6145 BTRFS_BLOCK_GROUP_DUP)) {
6146 *num_stripes = map->num_stripes;
6147 } else {
6148 stripe_index = stripe_nr % map->num_stripes;
6149 stripe_nr /= map->num_stripes;
6150 }
6151
6152 stripes = kcalloc(*num_stripes, sizeof(*stripes), GFP_NOFS);
6153 if (!stripes) {
6154 ret = -ENOMEM;
6155 goto out_free_map;
6156 }
6157
6158 for (i = 0; i < *num_stripes; i++) {
6159 stripes[i].physical =
6160 map->stripes[stripe_index].physical +
6161 stripe_offset + btrfs_stripe_nr_to_offset(stripe_nr);
6162 stripes[i].dev = map->stripes[stripe_index].dev;
6163
6164 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
6165 BTRFS_BLOCK_GROUP_RAID10)) {
6166 stripes[i].length = btrfs_stripe_nr_to_offset(stripes_per_dev);
6167
6168 if (i / sub_stripes < remaining_stripes)
6169 stripes[i].length += BTRFS_STRIPE_LEN;
6170
6171 /*
6172 * Special for the first stripe and
6173 * the last stripe:
6174 *
6175 * |-------|...|-------|
6176 * |----------|
6177 * off end_off
6178 */
6179 if (i < sub_stripes)
6180 stripes[i].length -= stripe_offset;
6181
6182 if (stripe_index >= last_stripe &&
6183 stripe_index <= (last_stripe +
6184 sub_stripes - 1))
6185 stripes[i].length -= stripe_end_offset;
6186
6187 if (i == sub_stripes - 1)
6188 stripe_offset = 0;
6189 } else {
6190 stripes[i].length = length;
6191 }
6192
6193 stripe_index++;
6194 if (stripe_index == map->num_stripes) {
6195 stripe_index = 0;
6196 stripe_nr++;
6197 }
6198 }
6199
6200 btrfs_free_chunk_map(map);
6201 return stripes;
6202 out_free_map:
6203 btrfs_free_chunk_map(map);
6204 return ERR_PTR(ret);
6205 }
6206
is_block_group_to_copy(struct btrfs_fs_info * fs_info,u64 logical)6207 static bool is_block_group_to_copy(struct btrfs_fs_info *fs_info, u64 logical)
6208 {
6209 struct btrfs_block_group *cache;
6210 bool ret;
6211
6212 /* Non zoned filesystem does not use "to_copy" flag */
6213 if (!btrfs_is_zoned(fs_info))
6214 return false;
6215
6216 cache = btrfs_lookup_block_group(fs_info, logical);
6217
6218 ret = test_bit(BLOCK_GROUP_FLAG_TO_COPY, &cache->runtime_flags);
6219
6220 btrfs_put_block_group(cache);
6221 return ret;
6222 }
6223
handle_ops_on_dev_replace(struct btrfs_io_context * bioc,struct btrfs_dev_replace * dev_replace,u64 logical,struct btrfs_io_geometry * io_geom)6224 static void handle_ops_on_dev_replace(struct btrfs_io_context *bioc,
6225 struct btrfs_dev_replace *dev_replace,
6226 u64 logical,
6227 struct btrfs_io_geometry *io_geom)
6228 {
6229 u64 srcdev_devid = dev_replace->srcdev->devid;
6230 /*
6231 * At this stage, num_stripes is still the real number of stripes,
6232 * excluding the duplicated stripes.
6233 */
6234 int num_stripes = io_geom->num_stripes;
6235 int max_errors = io_geom->max_errors;
6236 int nr_extra_stripes = 0;
6237 int i;
6238
6239 /*
6240 * A block group which has "to_copy" set will eventually be copied by
6241 * the dev-replace process. We can avoid cloning IO here.
6242 */
6243 if (is_block_group_to_copy(dev_replace->srcdev->fs_info, logical))
6244 return;
6245
6246 /*
6247 * Duplicate the write operations while the dev-replace procedure is
6248 * running. Since the copying of the old disk to the new disk takes
6249 * place at run time while the filesystem is mounted writable, the
6250 * regular write operations to the old disk have to be duplicated to go
6251 * to the new disk as well.
6252 *
6253 * Note that device->missing is handled by the caller, and that the
6254 * write to the old disk is already set up in the stripes array.
6255 */
6256 for (i = 0; i < num_stripes; i++) {
6257 struct btrfs_io_stripe *old = &bioc->stripes[i];
6258 struct btrfs_io_stripe *new = &bioc->stripes[num_stripes + nr_extra_stripes];
6259
6260 if (old->dev->devid != srcdev_devid)
6261 continue;
6262
6263 new->physical = old->physical;
6264 new->dev = dev_replace->tgtdev;
6265 if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK)
6266 bioc->replace_stripe_src = i;
6267 nr_extra_stripes++;
6268 }
6269
6270 /* We can only have at most 2 extra nr_stripes (for DUP). */
6271 ASSERT(nr_extra_stripes <= 2);
6272 /*
6273 * For GET_READ_MIRRORS, we can only return at most 1 extra stripe for
6274 * replace.
6275 * If we have 2 extra stripes, only choose the one with smaller physical.
6276 */
6277 if (io_geom->op == BTRFS_MAP_GET_READ_MIRRORS && nr_extra_stripes == 2) {
6278 struct btrfs_io_stripe *first = &bioc->stripes[num_stripes];
6279 struct btrfs_io_stripe *second = &bioc->stripes[num_stripes + 1];
6280
6281 /* Only DUP can have two extra stripes. */
6282 ASSERT(bioc->map_type & BTRFS_BLOCK_GROUP_DUP);
6283
6284 /*
6285 * Swap the last stripe stripes and reduce @nr_extra_stripes.
6286 * The extra stripe would still be there, but won't be accessed.
6287 */
6288 if (first->physical > second->physical) {
6289 swap(second->physical, first->physical);
6290 swap(second->dev, first->dev);
6291 nr_extra_stripes--;
6292 }
6293 }
6294
6295 io_geom->num_stripes = num_stripes + nr_extra_stripes;
6296 io_geom->max_errors = max_errors + nr_extra_stripes;
6297 bioc->replace_nr_stripes = nr_extra_stripes;
6298 }
6299
btrfs_max_io_len(struct btrfs_chunk_map * map,u64 offset,struct btrfs_io_geometry * io_geom)6300 static u64 btrfs_max_io_len(struct btrfs_chunk_map *map, u64 offset,
6301 struct btrfs_io_geometry *io_geom)
6302 {
6303 /*
6304 * Stripe_nr is the stripe where this block falls. stripe_offset is
6305 * the offset of this block in its stripe.
6306 */
6307 io_geom->stripe_offset = offset & BTRFS_STRIPE_LEN_MASK;
6308 io_geom->stripe_nr = offset >> BTRFS_STRIPE_LEN_SHIFT;
6309 ASSERT(io_geom->stripe_offset < U32_MAX);
6310
6311 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
6312 unsigned long full_stripe_len =
6313 btrfs_stripe_nr_to_offset(nr_data_stripes(map));
6314
6315 /*
6316 * For full stripe start, we use previously calculated
6317 * @stripe_nr. Align it to nr_data_stripes, then multiply with
6318 * STRIPE_LEN.
6319 *
6320 * By this we can avoid u64 division completely. And we have
6321 * to go rounddown(), not round_down(), as nr_data_stripes is
6322 * not ensured to be power of 2.
6323 */
6324 io_geom->raid56_full_stripe_start = btrfs_stripe_nr_to_offset(
6325 rounddown(io_geom->stripe_nr, nr_data_stripes(map)));
6326
6327 ASSERT(io_geom->raid56_full_stripe_start + full_stripe_len > offset);
6328 ASSERT(io_geom->raid56_full_stripe_start <= offset);
6329 /*
6330 * For writes to RAID56, allow to write a full stripe set, but
6331 * no straddling of stripe sets.
6332 */
6333 if (io_geom->op == BTRFS_MAP_WRITE)
6334 return full_stripe_len - (offset - io_geom->raid56_full_stripe_start);
6335 }
6336
6337 /*
6338 * For other RAID types and for RAID56 reads, allow a single stripe (on
6339 * a single disk).
6340 */
6341 if (map->type & BTRFS_BLOCK_GROUP_STRIPE_MASK)
6342 return BTRFS_STRIPE_LEN - io_geom->stripe_offset;
6343 return U64_MAX;
6344 }
6345
set_io_stripe(struct btrfs_fs_info * fs_info,u64 logical,u64 * length,struct btrfs_io_stripe * dst,struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6346 static int set_io_stripe(struct btrfs_fs_info *fs_info, u64 logical,
6347 u64 *length, struct btrfs_io_stripe *dst,
6348 struct btrfs_chunk_map *map,
6349 struct btrfs_io_geometry *io_geom)
6350 {
6351 dst->dev = map->stripes[io_geom->stripe_index].dev;
6352
6353 if (io_geom->op == BTRFS_MAP_READ && io_geom->use_rst)
6354 return btrfs_get_raid_extent_offset(fs_info, logical, length,
6355 map->type,
6356 io_geom->stripe_index, dst);
6357
6358 dst->physical = map->stripes[io_geom->stripe_index].physical +
6359 io_geom->stripe_offset +
6360 btrfs_stripe_nr_to_offset(io_geom->stripe_nr);
6361 return 0;
6362 }
6363
is_single_device_io(struct btrfs_fs_info * fs_info,const struct btrfs_io_stripe * smap,const struct btrfs_chunk_map * map,int num_alloc_stripes,struct btrfs_io_geometry * io_geom)6364 static bool is_single_device_io(struct btrfs_fs_info *fs_info,
6365 const struct btrfs_io_stripe *smap,
6366 const struct btrfs_chunk_map *map,
6367 int num_alloc_stripes,
6368 struct btrfs_io_geometry *io_geom)
6369 {
6370 if (!smap)
6371 return false;
6372
6373 if (num_alloc_stripes != 1)
6374 return false;
6375
6376 if (io_geom->use_rst && io_geom->op != BTRFS_MAP_READ)
6377 return false;
6378
6379 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) && io_geom->mirror_num > 1)
6380 return false;
6381
6382 return true;
6383 }
6384
map_blocks_raid0(const struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6385 static void map_blocks_raid0(const struct btrfs_chunk_map *map,
6386 struct btrfs_io_geometry *io_geom)
6387 {
6388 io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes;
6389 io_geom->stripe_nr /= map->num_stripes;
6390 if (io_geom->op == BTRFS_MAP_READ)
6391 io_geom->mirror_num = 1;
6392 }
6393
map_blocks_raid1(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom,bool dev_replace_is_ongoing)6394 static void map_blocks_raid1(struct btrfs_fs_info *fs_info,
6395 struct btrfs_chunk_map *map,
6396 struct btrfs_io_geometry *io_geom,
6397 bool dev_replace_is_ongoing)
6398 {
6399 if (io_geom->op != BTRFS_MAP_READ) {
6400 io_geom->num_stripes = map->num_stripes;
6401 return;
6402 }
6403
6404 if (io_geom->mirror_num) {
6405 io_geom->stripe_index = io_geom->mirror_num - 1;
6406 return;
6407 }
6408
6409 io_geom->stripe_index = find_live_mirror(fs_info, map, 0,
6410 dev_replace_is_ongoing);
6411 io_geom->mirror_num = io_geom->stripe_index + 1;
6412 }
6413
map_blocks_dup(const struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6414 static void map_blocks_dup(const struct btrfs_chunk_map *map,
6415 struct btrfs_io_geometry *io_geom)
6416 {
6417 if (io_geom->op != BTRFS_MAP_READ) {
6418 io_geom->num_stripes = map->num_stripes;
6419 return;
6420 }
6421
6422 if (io_geom->mirror_num) {
6423 io_geom->stripe_index = io_geom->mirror_num - 1;
6424 return;
6425 }
6426
6427 io_geom->mirror_num = 1;
6428 }
6429
map_blocks_raid10(struct btrfs_fs_info * fs_info,struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom,bool dev_replace_is_ongoing)6430 static void map_blocks_raid10(struct btrfs_fs_info *fs_info,
6431 struct btrfs_chunk_map *map,
6432 struct btrfs_io_geometry *io_geom,
6433 bool dev_replace_is_ongoing)
6434 {
6435 u32 factor = map->num_stripes / map->sub_stripes;
6436 int old_stripe_index;
6437
6438 io_geom->stripe_index = (io_geom->stripe_nr % factor) * map->sub_stripes;
6439 io_geom->stripe_nr /= factor;
6440
6441 if (io_geom->op != BTRFS_MAP_READ) {
6442 io_geom->num_stripes = map->sub_stripes;
6443 return;
6444 }
6445
6446 if (io_geom->mirror_num) {
6447 io_geom->stripe_index += io_geom->mirror_num - 1;
6448 return;
6449 }
6450
6451 old_stripe_index = io_geom->stripe_index;
6452 io_geom->stripe_index = find_live_mirror(fs_info, map,
6453 io_geom->stripe_index,
6454 dev_replace_is_ongoing);
6455 io_geom->mirror_num = io_geom->stripe_index - old_stripe_index + 1;
6456 }
6457
map_blocks_raid56_write(struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom,u64 logical,u64 * length)6458 static void map_blocks_raid56_write(struct btrfs_chunk_map *map,
6459 struct btrfs_io_geometry *io_geom,
6460 u64 logical, u64 *length)
6461 {
6462 int data_stripes = nr_data_stripes(map);
6463
6464 /*
6465 * Needs full stripe mapping.
6466 *
6467 * Push stripe_nr back to the start of the full stripe For those cases
6468 * needing a full stripe, @stripe_nr is the full stripe number.
6469 *
6470 * Originally we go raid56_full_stripe_start / full_stripe_len, but
6471 * that can be expensive. Here we just divide @stripe_nr with
6472 * @data_stripes.
6473 */
6474 io_geom->stripe_nr /= data_stripes;
6475
6476 /* RAID[56] write or recovery. Return all stripes */
6477 io_geom->num_stripes = map->num_stripes;
6478 io_geom->max_errors = btrfs_chunk_max_errors(map);
6479
6480 /* Return the length to the full stripe end. */
6481 *length = min(logical + *length,
6482 io_geom->raid56_full_stripe_start + map->start +
6483 btrfs_stripe_nr_to_offset(data_stripes)) -
6484 logical;
6485 io_geom->stripe_index = 0;
6486 io_geom->stripe_offset = 0;
6487 }
6488
map_blocks_raid56_read(struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6489 static void map_blocks_raid56_read(struct btrfs_chunk_map *map,
6490 struct btrfs_io_geometry *io_geom)
6491 {
6492 int data_stripes = nr_data_stripes(map);
6493
6494 ASSERT(io_geom->mirror_num <= 1);
6495 /* Just grab the data stripe directly. */
6496 io_geom->stripe_index = io_geom->stripe_nr % data_stripes;
6497 io_geom->stripe_nr /= data_stripes;
6498
6499 /* We distribute the parity blocks across stripes. */
6500 io_geom->stripe_index =
6501 (io_geom->stripe_nr + io_geom->stripe_index) % map->num_stripes;
6502
6503 if (io_geom->op == BTRFS_MAP_READ && io_geom->mirror_num < 1)
6504 io_geom->mirror_num = 1;
6505 }
6506
map_blocks_single(const struct btrfs_chunk_map * map,struct btrfs_io_geometry * io_geom)6507 static void map_blocks_single(const struct btrfs_chunk_map *map,
6508 struct btrfs_io_geometry *io_geom)
6509 {
6510 io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes;
6511 io_geom->stripe_nr /= map->num_stripes;
6512 io_geom->mirror_num = io_geom->stripe_index + 1;
6513 }
6514
6515 /*
6516 * Map one logical range to one or more physical ranges.
6517 *
6518 * @length: (Mandatory) mapped length of this run.
6519 * One logical range can be split into different segments
6520 * due to factors like zones and RAID0/5/6/10 stripe
6521 * boundaries.
6522 *
6523 * @bioc_ret: (Mandatory) returned btrfs_io_context structure.
6524 * which has one or more physical ranges (btrfs_io_stripe)
6525 * recorded inside.
6526 * Caller should call btrfs_put_bioc() to free it after use.
6527 *
6528 * @smap: (Optional) single physical range optimization.
6529 * If the map request can be fulfilled by one single
6530 * physical range, and this is parameter is not NULL,
6531 * then @bioc_ret would be NULL, and @smap would be
6532 * updated.
6533 *
6534 * @mirror_num_ret: (Mandatory) returned mirror number if the original
6535 * value is 0.
6536 *
6537 * Mirror number 0 means to choose any live mirrors.
6538 *
6539 * For non-RAID56 profiles, non-zero mirror_num means
6540 * the Nth mirror. (e.g. mirror_num 1 means the first
6541 * copy).
6542 *
6543 * For RAID56 profile, mirror 1 means rebuild from P and
6544 * the remaining data stripes.
6545 *
6546 * For RAID6 profile, mirror > 2 means mark another
6547 * data/P stripe error and rebuild from the remaining
6548 * stripes..
6549 */
btrfs_map_block(struct btrfs_fs_info * fs_info,enum btrfs_map_op op,u64 logical,u64 * length,struct btrfs_io_context ** bioc_ret,struct btrfs_io_stripe * smap,int * mirror_num_ret)6550 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
6551 u64 logical, u64 *length,
6552 struct btrfs_io_context **bioc_ret,
6553 struct btrfs_io_stripe *smap, int *mirror_num_ret)
6554 {
6555 struct btrfs_chunk_map *map;
6556 struct btrfs_io_geometry io_geom = { 0 };
6557 u64 map_offset;
6558 int ret = 0;
6559 int num_copies;
6560 struct btrfs_io_context *bioc = NULL;
6561 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
6562 int dev_replace_is_ongoing = 0;
6563 u16 num_alloc_stripes;
6564 u64 max_len;
6565
6566 ASSERT(bioc_ret);
6567
6568 io_geom.mirror_num = (mirror_num_ret ? *mirror_num_ret : 0);
6569 io_geom.num_stripes = 1;
6570 io_geom.stripe_index = 0;
6571 io_geom.op = op;
6572
6573 map = btrfs_get_chunk_map(fs_info, logical, *length);
6574 if (IS_ERR(map))
6575 return PTR_ERR(map);
6576
6577 num_copies = btrfs_chunk_map_num_copies(map);
6578 if (io_geom.mirror_num > num_copies)
6579 return -EINVAL;
6580
6581 map_offset = logical - map->start;
6582 io_geom.raid56_full_stripe_start = (u64)-1;
6583 max_len = btrfs_max_io_len(map, map_offset, &io_geom);
6584 *length = min_t(u64, map->chunk_len - map_offset, max_len);
6585 io_geom.use_rst = btrfs_need_stripe_tree_update(fs_info, map->type);
6586
6587 if (dev_replace->replace_task != current)
6588 down_read(&dev_replace->rwsem);
6589
6590 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
6591 /*
6592 * Hold the semaphore for read during the whole operation, write is
6593 * requested at commit time but must wait.
6594 */
6595 if (!dev_replace_is_ongoing && dev_replace->replace_task != current)
6596 up_read(&dev_replace->rwsem);
6597
6598 switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
6599 case BTRFS_BLOCK_GROUP_RAID0:
6600 map_blocks_raid0(map, &io_geom);
6601 break;
6602 case BTRFS_BLOCK_GROUP_RAID1:
6603 case BTRFS_BLOCK_GROUP_RAID1C3:
6604 case BTRFS_BLOCK_GROUP_RAID1C4:
6605 map_blocks_raid1(fs_info, map, &io_geom, dev_replace_is_ongoing);
6606 break;
6607 case BTRFS_BLOCK_GROUP_DUP:
6608 map_blocks_dup(map, &io_geom);
6609 break;
6610 case BTRFS_BLOCK_GROUP_RAID10:
6611 map_blocks_raid10(fs_info, map, &io_geom, dev_replace_is_ongoing);
6612 break;
6613 case BTRFS_BLOCK_GROUP_RAID5:
6614 case BTRFS_BLOCK_GROUP_RAID6:
6615 if (op != BTRFS_MAP_READ || io_geom.mirror_num > 1)
6616 map_blocks_raid56_write(map, &io_geom, logical, length);
6617 else
6618 map_blocks_raid56_read(map, &io_geom);
6619 break;
6620 default:
6621 /*
6622 * After this, stripe_nr is the number of stripes on this
6623 * device we have to walk to find the data, and stripe_index is
6624 * the number of our device in the stripe array
6625 */
6626 map_blocks_single(map, &io_geom);
6627 break;
6628 }
6629 if (io_geom.stripe_index >= map->num_stripes) {
6630 btrfs_crit(fs_info,
6631 "stripe index math went horribly wrong, got stripe_index=%u, num_stripes=%u",
6632 io_geom.stripe_index, map->num_stripes);
6633 ret = -EINVAL;
6634 goto out;
6635 }
6636
6637 num_alloc_stripes = io_geom.num_stripes;
6638 if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL &&
6639 op != BTRFS_MAP_READ)
6640 /*
6641 * For replace case, we need to add extra stripes for extra
6642 * duplicated stripes.
6643 *
6644 * For both WRITE and GET_READ_MIRRORS, we may have at most
6645 * 2 more stripes (DUP types, otherwise 1).
6646 */
6647 num_alloc_stripes += 2;
6648
6649 /*
6650 * If this I/O maps to a single device, try to return the device and
6651 * physical block information on the stack instead of allocating an
6652 * I/O context structure.
6653 */
6654 if (is_single_device_io(fs_info, smap, map, num_alloc_stripes, &io_geom)) {
6655 ret = set_io_stripe(fs_info, logical, length, smap, map, &io_geom);
6656 if (mirror_num_ret)
6657 *mirror_num_ret = io_geom.mirror_num;
6658 *bioc_ret = NULL;
6659 goto out;
6660 }
6661
6662 bioc = alloc_btrfs_io_context(fs_info, logical, num_alloc_stripes);
6663 if (!bioc) {
6664 ret = -ENOMEM;
6665 goto out;
6666 }
6667 bioc->map_type = map->type;
6668 bioc->use_rst = io_geom.use_rst;
6669
6670 /*
6671 * For RAID56 full map, we need to make sure the stripes[] follows the
6672 * rule that data stripes are all ordered, then followed with P and Q
6673 * (if we have).
6674 *
6675 * It's still mostly the same as other profiles, just with extra rotation.
6676 */
6677 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
6678 (op != BTRFS_MAP_READ || io_geom.mirror_num > 1)) {
6679 /*
6680 * For RAID56 @stripe_nr is already the number of full stripes
6681 * before us, which is also the rotation value (needs to modulo
6682 * with num_stripes).
6683 *
6684 * In this case, we just add @stripe_nr with @i, then do the
6685 * modulo, to reduce one modulo call.
6686 */
6687 bioc->full_stripe_logical = map->start +
6688 btrfs_stripe_nr_to_offset(io_geom.stripe_nr *
6689 nr_data_stripes(map));
6690 for (int i = 0; i < io_geom.num_stripes; i++) {
6691 struct btrfs_io_stripe *dst = &bioc->stripes[i];
6692 u32 stripe_index;
6693
6694 stripe_index = (i + io_geom.stripe_nr) % io_geom.num_stripes;
6695 dst->dev = map->stripes[stripe_index].dev;
6696 dst->physical =
6697 map->stripes[stripe_index].physical +
6698 io_geom.stripe_offset +
6699 btrfs_stripe_nr_to_offset(io_geom.stripe_nr);
6700 }
6701 } else {
6702 /*
6703 * For all other non-RAID56 profiles, just copy the target
6704 * stripe into the bioc.
6705 */
6706 for (int i = 0; i < io_geom.num_stripes; i++) {
6707 ret = set_io_stripe(fs_info, logical, length,
6708 &bioc->stripes[i], map, &io_geom);
6709 if (ret < 0)
6710 break;
6711 io_geom.stripe_index++;
6712 }
6713 }
6714
6715 if (ret) {
6716 *bioc_ret = NULL;
6717 btrfs_put_bioc(bioc);
6718 goto out;
6719 }
6720
6721 if (op != BTRFS_MAP_READ)
6722 io_geom.max_errors = btrfs_chunk_max_errors(map);
6723
6724 if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL &&
6725 op != BTRFS_MAP_READ) {
6726 handle_ops_on_dev_replace(bioc, dev_replace, logical, &io_geom);
6727 }
6728
6729 *bioc_ret = bioc;
6730 bioc->num_stripes = io_geom.num_stripes;
6731 bioc->max_errors = io_geom.max_errors;
6732 bioc->mirror_num = io_geom.mirror_num;
6733
6734 out:
6735 if (dev_replace_is_ongoing && dev_replace->replace_task != current) {
6736 lockdep_assert_held(&dev_replace->rwsem);
6737 /* Unlock and let waiting writers proceed */
6738 up_read(&dev_replace->rwsem);
6739 }
6740 btrfs_free_chunk_map(map);
6741 return ret;
6742 }
6743
dev_args_match_fs_devices(const struct btrfs_dev_lookup_args * args,const struct btrfs_fs_devices * fs_devices)6744 static bool dev_args_match_fs_devices(const struct btrfs_dev_lookup_args *args,
6745 const struct btrfs_fs_devices *fs_devices)
6746 {
6747 if (args->fsid == NULL)
6748 return true;
6749 if (memcmp(fs_devices->metadata_uuid, args->fsid, BTRFS_FSID_SIZE) == 0)
6750 return true;
6751 return false;
6752 }
6753
dev_args_match_device(const struct btrfs_dev_lookup_args * args,const struct btrfs_device * device)6754 static bool dev_args_match_device(const struct btrfs_dev_lookup_args *args,
6755 const struct btrfs_device *device)
6756 {
6757 if (args->missing) {
6758 if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state) &&
6759 !device->bdev)
6760 return true;
6761 return false;
6762 }
6763
6764 if (device->devid != args->devid)
6765 return false;
6766 if (args->uuid && memcmp(device->uuid, args->uuid, BTRFS_UUID_SIZE) != 0)
6767 return false;
6768 return true;
6769 }
6770
6771 /*
6772 * Find a device specified by @devid or @uuid in the list of @fs_devices, or
6773 * return NULL.
6774 *
6775 * If devid and uuid are both specified, the match must be exact, otherwise
6776 * only devid is used.
6777 */
btrfs_find_device(const struct btrfs_fs_devices * fs_devices,const struct btrfs_dev_lookup_args * args)6778 struct btrfs_device *btrfs_find_device(const struct btrfs_fs_devices *fs_devices,
6779 const struct btrfs_dev_lookup_args *args)
6780 {
6781 struct btrfs_device *device;
6782 struct btrfs_fs_devices *seed_devs;
6783
6784 if (dev_args_match_fs_devices(args, fs_devices)) {
6785 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6786 if (dev_args_match_device(args, device))
6787 return device;
6788 }
6789 }
6790
6791 list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
6792 if (!dev_args_match_fs_devices(args, seed_devs))
6793 continue;
6794 list_for_each_entry(device, &seed_devs->devices, dev_list) {
6795 if (dev_args_match_device(args, device))
6796 return device;
6797 }
6798 }
6799
6800 return NULL;
6801 }
6802
add_missing_dev(struct btrfs_fs_devices * fs_devices,u64 devid,u8 * dev_uuid)6803 static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices,
6804 u64 devid, u8 *dev_uuid)
6805 {
6806 struct btrfs_device *device;
6807 unsigned int nofs_flag;
6808
6809 /*
6810 * We call this under the chunk_mutex, so we want to use NOFS for this
6811 * allocation, however we don't want to change btrfs_alloc_device() to
6812 * always do NOFS because we use it in a lot of other GFP_KERNEL safe
6813 * places.
6814 */
6815
6816 nofs_flag = memalloc_nofs_save();
6817 device = btrfs_alloc_device(NULL, &devid, dev_uuid, NULL);
6818 memalloc_nofs_restore(nofs_flag);
6819 if (IS_ERR(device))
6820 return device;
6821
6822 list_add(&device->dev_list, &fs_devices->devices);
6823 device->fs_devices = fs_devices;
6824 fs_devices->num_devices++;
6825
6826 set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
6827 fs_devices->missing_devices++;
6828
6829 return device;
6830 }
6831
6832 /*
6833 * Allocate new device struct, set up devid and UUID.
6834 *
6835 * @fs_info: used only for generating a new devid, can be NULL if
6836 * devid is provided (i.e. @devid != NULL).
6837 * @devid: a pointer to devid for this device. If NULL a new devid
6838 * is generated.
6839 * @uuid: a pointer to UUID for this device. If NULL a new UUID
6840 * is generated.
6841 * @path: a pointer to device path if available, NULL otherwise.
6842 *
6843 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
6844 * on error. Returned struct is not linked onto any lists and must be
6845 * destroyed with btrfs_free_device.
6846 */
btrfs_alloc_device(struct btrfs_fs_info * fs_info,const u64 * devid,const u8 * uuid,const char * path)6847 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
6848 const u64 *devid, const u8 *uuid,
6849 const char *path)
6850 {
6851 struct btrfs_device *dev;
6852 u64 tmp;
6853
6854 if (WARN_ON(!devid && !fs_info))
6855 return ERR_PTR(-EINVAL);
6856
6857 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
6858 if (!dev)
6859 return ERR_PTR(-ENOMEM);
6860
6861 INIT_LIST_HEAD(&dev->dev_list);
6862 INIT_LIST_HEAD(&dev->dev_alloc_list);
6863 INIT_LIST_HEAD(&dev->post_commit_list);
6864
6865 atomic_set(&dev->dev_stats_ccnt, 0);
6866 btrfs_device_data_ordered_init(dev);
6867 extent_io_tree_init(fs_info, &dev->alloc_state, IO_TREE_DEVICE_ALLOC_STATE);
6868
6869 if (devid)
6870 tmp = *devid;
6871 else {
6872 int ret;
6873
6874 ret = find_next_devid(fs_info, &tmp);
6875 if (ret) {
6876 btrfs_free_device(dev);
6877 return ERR_PTR(ret);
6878 }
6879 }
6880 dev->devid = tmp;
6881
6882 if (uuid)
6883 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
6884 else
6885 generate_random_uuid(dev->uuid);
6886
6887 if (path) {
6888 struct rcu_string *name;
6889
6890 name = rcu_string_strdup(path, GFP_KERNEL);
6891 if (!name) {
6892 btrfs_free_device(dev);
6893 return ERR_PTR(-ENOMEM);
6894 }
6895 rcu_assign_pointer(dev->name, name);
6896 }
6897
6898 return dev;
6899 }
6900
btrfs_report_missing_device(struct btrfs_fs_info * fs_info,u64 devid,u8 * uuid,bool error)6901 static void btrfs_report_missing_device(struct btrfs_fs_info *fs_info,
6902 u64 devid, u8 *uuid, bool error)
6903 {
6904 if (error)
6905 btrfs_err_rl(fs_info, "devid %llu uuid %pU is missing",
6906 devid, uuid);
6907 else
6908 btrfs_warn_rl(fs_info, "devid %llu uuid %pU is missing",
6909 devid, uuid);
6910 }
6911
btrfs_calc_stripe_length(const struct btrfs_chunk_map * map)6912 u64 btrfs_calc_stripe_length(const struct btrfs_chunk_map *map)
6913 {
6914 const int data_stripes = calc_data_stripes(map->type, map->num_stripes);
6915
6916 return div_u64(map->chunk_len, data_stripes);
6917 }
6918
6919 #if BITS_PER_LONG == 32
6920 /*
6921 * Due to page cache limit, metadata beyond BTRFS_32BIT_MAX_FILE_SIZE
6922 * can't be accessed on 32bit systems.
6923 *
6924 * This function do mount time check to reject the fs if it already has
6925 * metadata chunk beyond that limit.
6926 */
check_32bit_meta_chunk(struct btrfs_fs_info * fs_info,u64 logical,u64 length,u64 type)6927 static int check_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
6928 u64 logical, u64 length, u64 type)
6929 {
6930 if (!(type & BTRFS_BLOCK_GROUP_METADATA))
6931 return 0;
6932
6933 if (logical + length < MAX_LFS_FILESIZE)
6934 return 0;
6935
6936 btrfs_err_32bit_limit(fs_info);
6937 return -EOVERFLOW;
6938 }
6939
6940 /*
6941 * This is to give early warning for any metadata chunk reaching
6942 * BTRFS_32BIT_EARLY_WARN_THRESHOLD.
6943 * Although we can still access the metadata, it's not going to be possible
6944 * once the limit is reached.
6945 */
warn_32bit_meta_chunk(struct btrfs_fs_info * fs_info,u64 logical,u64 length,u64 type)6946 static void warn_32bit_meta_chunk(struct btrfs_fs_info *fs_info,
6947 u64 logical, u64 length, u64 type)
6948 {
6949 if (!(type & BTRFS_BLOCK_GROUP_METADATA))
6950 return;
6951
6952 if (logical + length < BTRFS_32BIT_EARLY_WARN_THRESHOLD)
6953 return;
6954
6955 btrfs_warn_32bit_limit(fs_info);
6956 }
6957 #endif
6958
handle_missing_device(struct btrfs_fs_info * fs_info,u64 devid,u8 * uuid)6959 static struct btrfs_device *handle_missing_device(struct btrfs_fs_info *fs_info,
6960 u64 devid, u8 *uuid)
6961 {
6962 struct btrfs_device *dev;
6963
6964 if (!btrfs_test_opt(fs_info, DEGRADED)) {
6965 btrfs_report_missing_device(fs_info, devid, uuid, true);
6966 return ERR_PTR(-ENOENT);
6967 }
6968
6969 dev = add_missing_dev(fs_info->fs_devices, devid, uuid);
6970 if (IS_ERR(dev)) {
6971 btrfs_err(fs_info, "failed to init missing device %llu: %ld",
6972 devid, PTR_ERR(dev));
6973 return dev;
6974 }
6975 btrfs_report_missing_device(fs_info, devid, uuid, false);
6976
6977 return dev;
6978 }
6979
read_one_chunk(struct btrfs_key * key,struct extent_buffer * leaf,struct btrfs_chunk * chunk)6980 static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf,
6981 struct btrfs_chunk *chunk)
6982 {
6983 BTRFS_DEV_LOOKUP_ARGS(args);
6984 struct btrfs_fs_info *fs_info = leaf->fs_info;
6985 struct btrfs_chunk_map *map;
6986 u64 logical;
6987 u64 length;
6988 u64 devid;
6989 u64 type;
6990 u8 uuid[BTRFS_UUID_SIZE];
6991 int index;
6992 int num_stripes;
6993 int ret;
6994 int i;
6995
6996 logical = key->offset;
6997 length = btrfs_chunk_length(leaf, chunk);
6998 type = btrfs_chunk_type(leaf, chunk);
6999 index = btrfs_bg_flags_to_raid_index(type);
7000 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
7001
7002 #if BITS_PER_LONG == 32
7003 ret = check_32bit_meta_chunk(fs_info, logical, length, type);
7004 if (ret < 0)
7005 return ret;
7006 warn_32bit_meta_chunk(fs_info, logical, length, type);
7007 #endif
7008
7009 map = btrfs_find_chunk_map(fs_info, logical, 1);
7010
7011 /* already mapped? */
7012 if (map && map->start <= logical && map->start + map->chunk_len > logical) {
7013 btrfs_free_chunk_map(map);
7014 return 0;
7015 } else if (map) {
7016 btrfs_free_chunk_map(map);
7017 }
7018
7019 map = btrfs_alloc_chunk_map(num_stripes, GFP_NOFS);
7020 if (!map)
7021 return -ENOMEM;
7022
7023 map->start = logical;
7024 map->chunk_len = length;
7025 map->num_stripes = num_stripes;
7026 map->io_width = btrfs_chunk_io_width(leaf, chunk);
7027 map->io_align = btrfs_chunk_io_align(leaf, chunk);
7028 map->type = type;
7029 /*
7030 * We can't use the sub_stripes value, as for profiles other than
7031 * RAID10, they may have 0 as sub_stripes for filesystems created by
7032 * older mkfs (<v5.4).
7033 * In that case, it can cause divide-by-zero errors later.
7034 * Since currently sub_stripes is fixed for each profile, let's
7035 * use the trusted value instead.
7036 */
7037 map->sub_stripes = btrfs_raid_array[index].sub_stripes;
7038 map->verified_stripes = 0;
7039 map->stripe_size = btrfs_calc_stripe_length(map);
7040 for (i = 0; i < num_stripes; i++) {
7041 map->stripes[i].physical =
7042 btrfs_stripe_offset_nr(leaf, chunk, i);
7043 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
7044 args.devid = devid;
7045 read_extent_buffer(leaf, uuid, (unsigned long)
7046 btrfs_stripe_dev_uuid_nr(chunk, i),
7047 BTRFS_UUID_SIZE);
7048 args.uuid = uuid;
7049 map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices, &args);
7050 if (!map->stripes[i].dev) {
7051 map->stripes[i].dev = handle_missing_device(fs_info,
7052 devid, uuid);
7053 if (IS_ERR(map->stripes[i].dev)) {
7054 ret = PTR_ERR(map->stripes[i].dev);
7055 btrfs_free_chunk_map(map);
7056 return ret;
7057 }
7058 }
7059
7060 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
7061 &(map->stripes[i].dev->dev_state));
7062 }
7063
7064 ret = btrfs_add_chunk_map(fs_info, map);
7065 if (ret < 0) {
7066 btrfs_err(fs_info,
7067 "failed to add chunk map, start=%llu len=%llu: %d",
7068 map->start, map->chunk_len, ret);
7069 btrfs_free_chunk_map(map);
7070 }
7071
7072 return ret;
7073 }
7074
fill_device_from_item(struct extent_buffer * leaf,struct btrfs_dev_item * dev_item,struct btrfs_device * device)7075 static void fill_device_from_item(struct extent_buffer *leaf,
7076 struct btrfs_dev_item *dev_item,
7077 struct btrfs_device *device)
7078 {
7079 unsigned long ptr;
7080
7081 device->devid = btrfs_device_id(leaf, dev_item);
7082 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
7083 device->total_bytes = device->disk_total_bytes;
7084 device->commit_total_bytes = device->disk_total_bytes;
7085 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
7086 device->commit_bytes_used = device->bytes_used;
7087 device->type = btrfs_device_type(leaf, dev_item);
7088 device->io_align = btrfs_device_io_align(leaf, dev_item);
7089 device->io_width = btrfs_device_io_width(leaf, dev_item);
7090 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
7091 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
7092 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
7093
7094 ptr = btrfs_device_uuid(dev_item);
7095 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
7096 }
7097
open_seed_devices(struct btrfs_fs_info * fs_info,u8 * fsid)7098 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info,
7099 u8 *fsid)
7100 {
7101 struct btrfs_fs_devices *fs_devices;
7102 int ret;
7103
7104 lockdep_assert_held(&uuid_mutex);
7105 ASSERT(fsid);
7106
7107 /* This will match only for multi-device seed fs */
7108 list_for_each_entry(fs_devices, &fs_info->fs_devices->seed_list, seed_list)
7109 if (!memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE))
7110 return fs_devices;
7111
7112
7113 fs_devices = find_fsid(fsid, NULL);
7114 if (!fs_devices) {
7115 if (!btrfs_test_opt(fs_info, DEGRADED)) {
7116 btrfs_err(fs_info,
7117 "failed to find fsid %pU when attempting to open seed devices",
7118 fsid);
7119 return ERR_PTR(-ENOENT);
7120 }
7121
7122 fs_devices = alloc_fs_devices(fsid);
7123 if (IS_ERR(fs_devices))
7124 return fs_devices;
7125
7126 fs_devices->seeding = true;
7127 fs_devices->opened = 1;
7128 return fs_devices;
7129 }
7130
7131 /*
7132 * Upon first call for a seed fs fsid, just create a private copy of the
7133 * respective fs_devices and anchor it at fs_info->fs_devices->seed_list
7134 */
7135 fs_devices = clone_fs_devices(fs_devices);
7136 if (IS_ERR(fs_devices))
7137 return fs_devices;
7138
7139 ret = open_fs_devices(fs_devices, BLK_OPEN_READ, fs_info->bdev_holder);
7140 if (ret) {
7141 free_fs_devices(fs_devices);
7142 return ERR_PTR(ret);
7143 }
7144
7145 if (!fs_devices->seeding) {
7146 close_fs_devices(fs_devices);
7147 free_fs_devices(fs_devices);
7148 return ERR_PTR(-EINVAL);
7149 }
7150
7151 list_add(&fs_devices->seed_list, &fs_info->fs_devices->seed_list);
7152
7153 return fs_devices;
7154 }
7155
read_one_dev(struct extent_buffer * leaf,struct btrfs_dev_item * dev_item)7156 static int read_one_dev(struct extent_buffer *leaf,
7157 struct btrfs_dev_item *dev_item)
7158 {
7159 BTRFS_DEV_LOOKUP_ARGS(args);
7160 struct btrfs_fs_info *fs_info = leaf->fs_info;
7161 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7162 struct btrfs_device *device;
7163 u64 devid;
7164 int ret;
7165 u8 fs_uuid[BTRFS_FSID_SIZE];
7166 u8 dev_uuid[BTRFS_UUID_SIZE];
7167
7168 devid = btrfs_device_id(leaf, dev_item);
7169 args.devid = devid;
7170 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
7171 BTRFS_UUID_SIZE);
7172 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
7173 BTRFS_FSID_SIZE);
7174 args.uuid = dev_uuid;
7175 args.fsid = fs_uuid;
7176
7177 if (memcmp(fs_uuid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE)) {
7178 fs_devices = open_seed_devices(fs_info, fs_uuid);
7179 if (IS_ERR(fs_devices))
7180 return PTR_ERR(fs_devices);
7181 }
7182
7183 device = btrfs_find_device(fs_info->fs_devices, &args);
7184 if (!device) {
7185 if (!btrfs_test_opt(fs_info, DEGRADED)) {
7186 btrfs_report_missing_device(fs_info, devid,
7187 dev_uuid, true);
7188 return -ENOENT;
7189 }
7190
7191 device = add_missing_dev(fs_devices, devid, dev_uuid);
7192 if (IS_ERR(device)) {
7193 btrfs_err(fs_info,
7194 "failed to add missing dev %llu: %ld",
7195 devid, PTR_ERR(device));
7196 return PTR_ERR(device);
7197 }
7198 btrfs_report_missing_device(fs_info, devid, dev_uuid, false);
7199 } else {
7200 if (!device->bdev) {
7201 if (!btrfs_test_opt(fs_info, DEGRADED)) {
7202 btrfs_report_missing_device(fs_info,
7203 devid, dev_uuid, true);
7204 return -ENOENT;
7205 }
7206 btrfs_report_missing_device(fs_info, devid,
7207 dev_uuid, false);
7208 }
7209
7210 if (!device->bdev &&
7211 !test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) {
7212 /*
7213 * this happens when a device that was properly setup
7214 * in the device info lists suddenly goes bad.
7215 * device->bdev is NULL, and so we have to set
7216 * device->missing to one here
7217 */
7218 device->fs_devices->missing_devices++;
7219 set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state);
7220 }
7221
7222 /* Move the device to its own fs_devices */
7223 if (device->fs_devices != fs_devices) {
7224 ASSERT(test_bit(BTRFS_DEV_STATE_MISSING,
7225 &device->dev_state));
7226
7227 list_move(&device->dev_list, &fs_devices->devices);
7228 device->fs_devices->num_devices--;
7229 fs_devices->num_devices++;
7230
7231 device->fs_devices->missing_devices--;
7232 fs_devices->missing_devices++;
7233
7234 device->fs_devices = fs_devices;
7235 }
7236 }
7237
7238 if (device->fs_devices != fs_info->fs_devices) {
7239 BUG_ON(test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state));
7240 if (device->generation !=
7241 btrfs_device_generation(leaf, dev_item))
7242 return -EINVAL;
7243 }
7244
7245 fill_device_from_item(leaf, dev_item, device);
7246 if (device->bdev) {
7247 u64 max_total_bytes = bdev_nr_bytes(device->bdev);
7248
7249 if (device->total_bytes > max_total_bytes) {
7250 btrfs_err(fs_info,
7251 "device total_bytes should be at most %llu but found %llu",
7252 max_total_bytes, device->total_bytes);
7253 return -EINVAL;
7254 }
7255 }
7256 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
7257 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
7258 !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
7259 device->fs_devices->total_rw_bytes += device->total_bytes;
7260 atomic64_add(device->total_bytes - device->bytes_used,
7261 &fs_info->free_chunk_space);
7262 }
7263 ret = 0;
7264 return ret;
7265 }
7266
btrfs_read_sys_array(struct btrfs_fs_info * fs_info)7267 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info)
7268 {
7269 struct btrfs_super_block *super_copy = fs_info->super_copy;
7270 struct extent_buffer *sb;
7271 u8 *array_ptr;
7272 unsigned long sb_array_offset;
7273 int ret = 0;
7274 u32 array_size;
7275 u32 cur_offset;
7276 struct btrfs_key key;
7277
7278 ASSERT(BTRFS_SUPER_INFO_SIZE <= fs_info->nodesize);
7279
7280 /*
7281 * We allocated a dummy extent, just to use extent buffer accessors.
7282 * There will be unused space after BTRFS_SUPER_INFO_SIZE, but
7283 * that's fine, we will not go beyond system chunk array anyway.
7284 */
7285 sb = alloc_dummy_extent_buffer(fs_info, BTRFS_SUPER_INFO_OFFSET);
7286 if (!sb)
7287 return -ENOMEM;
7288 set_extent_buffer_uptodate(sb);
7289
7290 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
7291 array_size = btrfs_super_sys_array_size(super_copy);
7292
7293 array_ptr = super_copy->sys_chunk_array;
7294 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
7295 cur_offset = 0;
7296
7297 while (cur_offset < array_size) {
7298 struct btrfs_chunk *chunk;
7299 struct btrfs_disk_key *disk_key = (struct btrfs_disk_key *)array_ptr;
7300 u32 len = sizeof(*disk_key);
7301
7302 /*
7303 * The sys_chunk_array has been already verified at super block
7304 * read time. Only do ASSERT()s for basic checks.
7305 */
7306 ASSERT(cur_offset + len <= array_size);
7307
7308 btrfs_disk_key_to_cpu(&key, disk_key);
7309
7310 array_ptr += len;
7311 sb_array_offset += len;
7312 cur_offset += len;
7313
7314 ASSERT(key.type == BTRFS_CHUNK_ITEM_KEY);
7315
7316 chunk = (struct btrfs_chunk *)sb_array_offset;
7317 ASSERT(btrfs_chunk_type(sb, chunk) & BTRFS_BLOCK_GROUP_SYSTEM);
7318
7319 len = btrfs_chunk_item_size(btrfs_chunk_num_stripes(sb, chunk));
7320
7321 ASSERT(cur_offset + len <= array_size);
7322
7323 ret = read_one_chunk(&key, sb, chunk);
7324 if (ret)
7325 break;
7326
7327 array_ptr += len;
7328 sb_array_offset += len;
7329 cur_offset += len;
7330 }
7331 clear_extent_buffer_uptodate(sb);
7332 free_extent_buffer_stale(sb);
7333 return ret;
7334 }
7335
7336 /*
7337 * Check if all chunks in the fs are OK for read-write degraded mount
7338 *
7339 * If the @failing_dev is specified, it's accounted as missing.
7340 *
7341 * Return true if all chunks meet the minimal RW mount requirements.
7342 * Return false if any chunk doesn't meet the minimal RW mount requirements.
7343 */
btrfs_check_rw_degradable(struct btrfs_fs_info * fs_info,struct btrfs_device * failing_dev)7344 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info,
7345 struct btrfs_device *failing_dev)
7346 {
7347 struct btrfs_chunk_map *map;
7348 u64 next_start;
7349 bool ret = true;
7350
7351 map = btrfs_find_chunk_map(fs_info, 0, U64_MAX);
7352 /* No chunk at all? Return false anyway */
7353 if (!map) {
7354 ret = false;
7355 goto out;
7356 }
7357 while (map) {
7358 int missing = 0;
7359 int max_tolerated;
7360 int i;
7361
7362 max_tolerated =
7363 btrfs_get_num_tolerated_disk_barrier_failures(
7364 map->type);
7365 for (i = 0; i < map->num_stripes; i++) {
7366 struct btrfs_device *dev = map->stripes[i].dev;
7367
7368 if (!dev || !dev->bdev ||
7369 test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) ||
7370 dev->last_flush_error)
7371 missing++;
7372 else if (failing_dev && failing_dev == dev)
7373 missing++;
7374 }
7375 if (missing > max_tolerated) {
7376 if (!failing_dev)
7377 btrfs_warn(fs_info,
7378 "chunk %llu missing %d devices, max tolerance is %d for writable mount",
7379 map->start, missing, max_tolerated);
7380 btrfs_free_chunk_map(map);
7381 ret = false;
7382 goto out;
7383 }
7384 next_start = map->start + map->chunk_len;
7385 btrfs_free_chunk_map(map);
7386
7387 map = btrfs_find_chunk_map(fs_info, next_start, U64_MAX - next_start);
7388 }
7389 out:
7390 return ret;
7391 }
7392
readahead_tree_node_children(struct extent_buffer * node)7393 static void readahead_tree_node_children(struct extent_buffer *node)
7394 {
7395 int i;
7396 const int nr_items = btrfs_header_nritems(node);
7397
7398 for (i = 0; i < nr_items; i++)
7399 btrfs_readahead_node_child(node, i);
7400 }
7401
btrfs_read_chunk_tree(struct btrfs_fs_info * fs_info)7402 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info)
7403 {
7404 struct btrfs_root *root = fs_info->chunk_root;
7405 struct btrfs_path *path;
7406 struct extent_buffer *leaf;
7407 struct btrfs_key key;
7408 struct btrfs_key found_key;
7409 int ret;
7410 int slot;
7411 int iter_ret = 0;
7412 u64 total_dev = 0;
7413 u64 last_ra_node = 0;
7414
7415 path = btrfs_alloc_path();
7416 if (!path)
7417 return -ENOMEM;
7418
7419 /*
7420 * uuid_mutex is needed only if we are mounting a sprout FS
7421 * otherwise we don't need it.
7422 */
7423 mutex_lock(&uuid_mutex);
7424
7425 /*
7426 * It is possible for mount and umount to race in such a way that
7427 * we execute this code path, but open_fs_devices failed to clear
7428 * total_rw_bytes. We certainly want it cleared before reading the
7429 * device items, so clear it here.
7430 */
7431 fs_info->fs_devices->total_rw_bytes = 0;
7432
7433 /*
7434 * Lockdep complains about possible circular locking dependency between
7435 * a disk's open_mutex (struct gendisk.open_mutex), the rw semaphores
7436 * used for freeze procection of a fs (struct super_block.s_writers),
7437 * which we take when starting a transaction, and extent buffers of the
7438 * chunk tree if we call read_one_dev() while holding a lock on an
7439 * extent buffer of the chunk tree. Since we are mounting the filesystem
7440 * and at this point there can't be any concurrent task modifying the
7441 * chunk tree, to keep it simple, just skip locking on the chunk tree.
7442 */
7443 ASSERT(!test_bit(BTRFS_FS_OPEN, &fs_info->flags));
7444 path->skip_locking = 1;
7445
7446 /*
7447 * Read all device items, and then all the chunk items. All
7448 * device items are found before any chunk item (their object id
7449 * is smaller than the lowest possible object id for a chunk
7450 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
7451 */
7452 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
7453 key.type = 0;
7454 key.offset = 0;
7455 btrfs_for_each_slot(root, &key, &found_key, path, iter_ret) {
7456 struct extent_buffer *node = path->nodes[1];
7457
7458 leaf = path->nodes[0];
7459 slot = path->slots[0];
7460
7461 if (node) {
7462 if (last_ra_node != node->start) {
7463 readahead_tree_node_children(node);
7464 last_ra_node = node->start;
7465 }
7466 }
7467 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
7468 struct btrfs_dev_item *dev_item;
7469 dev_item = btrfs_item_ptr(leaf, slot,
7470 struct btrfs_dev_item);
7471 ret = read_one_dev(leaf, dev_item);
7472 if (ret)
7473 goto error;
7474 total_dev++;
7475 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
7476 struct btrfs_chunk *chunk;
7477
7478 /*
7479 * We are only called at mount time, so no need to take
7480 * fs_info->chunk_mutex. Plus, to avoid lockdep warnings,
7481 * we always lock first fs_info->chunk_mutex before
7482 * acquiring any locks on the chunk tree. This is a
7483 * requirement for chunk allocation, see the comment on
7484 * top of btrfs_chunk_alloc() for details.
7485 */
7486 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
7487 ret = read_one_chunk(&found_key, leaf, chunk);
7488 if (ret)
7489 goto error;
7490 }
7491 }
7492 /* Catch error found during iteration */
7493 if (iter_ret < 0) {
7494 ret = iter_ret;
7495 goto error;
7496 }
7497
7498 /*
7499 * After loading chunk tree, we've got all device information,
7500 * do another round of validation checks.
7501 */
7502 if (total_dev != fs_info->fs_devices->total_devices) {
7503 btrfs_warn(fs_info,
7504 "super block num_devices %llu mismatch with DEV_ITEM count %llu, will be repaired on next transaction commit",
7505 btrfs_super_num_devices(fs_info->super_copy),
7506 total_dev);
7507 fs_info->fs_devices->total_devices = total_dev;
7508 btrfs_set_super_num_devices(fs_info->super_copy, total_dev);
7509 }
7510 if (btrfs_super_total_bytes(fs_info->super_copy) <
7511 fs_info->fs_devices->total_rw_bytes) {
7512 btrfs_err(fs_info,
7513 "super_total_bytes %llu mismatch with fs_devices total_rw_bytes %llu",
7514 btrfs_super_total_bytes(fs_info->super_copy),
7515 fs_info->fs_devices->total_rw_bytes);
7516 ret = -EINVAL;
7517 goto error;
7518 }
7519 ret = 0;
7520 error:
7521 mutex_unlock(&uuid_mutex);
7522
7523 btrfs_free_path(path);
7524 return ret;
7525 }
7526
btrfs_init_devices_late(struct btrfs_fs_info * fs_info)7527 int btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
7528 {
7529 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
7530 struct btrfs_device *device;
7531 int ret = 0;
7532
7533 mutex_lock(&fs_devices->device_list_mutex);
7534 list_for_each_entry(device, &fs_devices->devices, dev_list)
7535 device->fs_info = fs_info;
7536
7537 list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
7538 list_for_each_entry(device, &seed_devs->devices, dev_list) {
7539 device->fs_info = fs_info;
7540 ret = btrfs_get_dev_zone_info(device, false);
7541 if (ret)
7542 break;
7543 }
7544
7545 seed_devs->fs_info = fs_info;
7546 }
7547 mutex_unlock(&fs_devices->device_list_mutex);
7548
7549 return ret;
7550 }
7551
btrfs_dev_stats_value(const struct extent_buffer * eb,const struct btrfs_dev_stats_item * ptr,int index)7552 static u64 btrfs_dev_stats_value(const struct extent_buffer *eb,
7553 const struct btrfs_dev_stats_item *ptr,
7554 int index)
7555 {
7556 u64 val;
7557
7558 read_extent_buffer(eb, &val,
7559 offsetof(struct btrfs_dev_stats_item, values) +
7560 ((unsigned long)ptr) + (index * sizeof(u64)),
7561 sizeof(val));
7562 return val;
7563 }
7564
btrfs_set_dev_stats_value(struct extent_buffer * eb,struct btrfs_dev_stats_item * ptr,int index,u64 val)7565 static void btrfs_set_dev_stats_value(struct extent_buffer *eb,
7566 struct btrfs_dev_stats_item *ptr,
7567 int index, u64 val)
7568 {
7569 write_extent_buffer(eb, &val,
7570 offsetof(struct btrfs_dev_stats_item, values) +
7571 ((unsigned long)ptr) + (index * sizeof(u64)),
7572 sizeof(val));
7573 }
7574
btrfs_device_init_dev_stats(struct btrfs_device * device,struct btrfs_path * path)7575 static int btrfs_device_init_dev_stats(struct btrfs_device *device,
7576 struct btrfs_path *path)
7577 {
7578 struct btrfs_dev_stats_item *ptr;
7579 struct extent_buffer *eb;
7580 struct btrfs_key key;
7581 int item_size;
7582 int i, ret, slot;
7583
7584 if (!device->fs_info->dev_root)
7585 return 0;
7586
7587 key.objectid = BTRFS_DEV_STATS_OBJECTID;
7588 key.type = BTRFS_PERSISTENT_ITEM_KEY;
7589 key.offset = device->devid;
7590 ret = btrfs_search_slot(NULL, device->fs_info->dev_root, &key, path, 0, 0);
7591 if (ret) {
7592 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7593 btrfs_dev_stat_set(device, i, 0);
7594 device->dev_stats_valid = 1;
7595 btrfs_release_path(path);
7596 return ret < 0 ? ret : 0;
7597 }
7598 slot = path->slots[0];
7599 eb = path->nodes[0];
7600 item_size = btrfs_item_size(eb, slot);
7601
7602 ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_stats_item);
7603
7604 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
7605 if (item_size >= (1 + i) * sizeof(__le64))
7606 btrfs_dev_stat_set(device, i,
7607 btrfs_dev_stats_value(eb, ptr, i));
7608 else
7609 btrfs_dev_stat_set(device, i, 0);
7610 }
7611
7612 device->dev_stats_valid = 1;
7613 btrfs_dev_stat_print_on_load(device);
7614 btrfs_release_path(path);
7615
7616 return 0;
7617 }
7618
btrfs_init_dev_stats(struct btrfs_fs_info * fs_info)7619 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
7620 {
7621 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices, *seed_devs;
7622 struct btrfs_device *device;
7623 struct btrfs_path *path = NULL;
7624 int ret = 0;
7625
7626 path = btrfs_alloc_path();
7627 if (!path)
7628 return -ENOMEM;
7629
7630 mutex_lock(&fs_devices->device_list_mutex);
7631 list_for_each_entry(device, &fs_devices->devices, dev_list) {
7632 ret = btrfs_device_init_dev_stats(device, path);
7633 if (ret)
7634 goto out;
7635 }
7636 list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) {
7637 list_for_each_entry(device, &seed_devs->devices, dev_list) {
7638 ret = btrfs_device_init_dev_stats(device, path);
7639 if (ret)
7640 goto out;
7641 }
7642 }
7643 out:
7644 mutex_unlock(&fs_devices->device_list_mutex);
7645
7646 btrfs_free_path(path);
7647 return ret;
7648 }
7649
update_dev_stat_item(struct btrfs_trans_handle * trans,struct btrfs_device * device)7650 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
7651 struct btrfs_device *device)
7652 {
7653 struct btrfs_fs_info *fs_info = trans->fs_info;
7654 struct btrfs_root *dev_root = fs_info->dev_root;
7655 struct btrfs_path *path;
7656 struct btrfs_key key;
7657 struct extent_buffer *eb;
7658 struct btrfs_dev_stats_item *ptr;
7659 int ret;
7660 int i;
7661
7662 key.objectid = BTRFS_DEV_STATS_OBJECTID;
7663 key.type = BTRFS_PERSISTENT_ITEM_KEY;
7664 key.offset = device->devid;
7665
7666 path = btrfs_alloc_path();
7667 if (!path)
7668 return -ENOMEM;
7669 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
7670 if (ret < 0) {
7671 btrfs_warn_in_rcu(fs_info,
7672 "error %d while searching for dev_stats item for device %s",
7673 ret, btrfs_dev_name(device));
7674 goto out;
7675 }
7676
7677 if (ret == 0 &&
7678 btrfs_item_size(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
7679 /* need to delete old one and insert a new one */
7680 ret = btrfs_del_item(trans, dev_root, path);
7681 if (ret != 0) {
7682 btrfs_warn_in_rcu(fs_info,
7683 "delete too small dev_stats item for device %s failed %d",
7684 btrfs_dev_name(device), ret);
7685 goto out;
7686 }
7687 ret = 1;
7688 }
7689
7690 if (ret == 1) {
7691 /* need to insert a new item */
7692 btrfs_release_path(path);
7693 ret = btrfs_insert_empty_item(trans, dev_root, path,
7694 &key, sizeof(*ptr));
7695 if (ret < 0) {
7696 btrfs_warn_in_rcu(fs_info,
7697 "insert dev_stats item for device %s failed %d",
7698 btrfs_dev_name(device), ret);
7699 goto out;
7700 }
7701 }
7702
7703 eb = path->nodes[0];
7704 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
7705 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7706 btrfs_set_dev_stats_value(eb, ptr, i,
7707 btrfs_dev_stat_read(device, i));
7708 out:
7709 btrfs_free_path(path);
7710 return ret;
7711 }
7712
7713 /*
7714 * called from commit_transaction. Writes all changed device stats to disk.
7715 */
btrfs_run_dev_stats(struct btrfs_trans_handle * trans)7716 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans)
7717 {
7718 struct btrfs_fs_info *fs_info = trans->fs_info;
7719 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7720 struct btrfs_device *device;
7721 int stats_cnt;
7722 int ret = 0;
7723
7724 mutex_lock(&fs_devices->device_list_mutex);
7725 list_for_each_entry(device, &fs_devices->devices, dev_list) {
7726 stats_cnt = atomic_read(&device->dev_stats_ccnt);
7727 if (!device->dev_stats_valid || stats_cnt == 0)
7728 continue;
7729
7730
7731 /*
7732 * There is a LOAD-LOAD control dependency between the value of
7733 * dev_stats_ccnt and updating the on-disk values which requires
7734 * reading the in-memory counters. Such control dependencies
7735 * require explicit read memory barriers.
7736 *
7737 * This memory barriers pairs with smp_mb__before_atomic in
7738 * btrfs_dev_stat_inc/btrfs_dev_stat_set and with the full
7739 * barrier implied by atomic_xchg in
7740 * btrfs_dev_stats_read_and_reset
7741 */
7742 smp_rmb();
7743
7744 ret = update_dev_stat_item(trans, device);
7745 if (!ret)
7746 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
7747 }
7748 mutex_unlock(&fs_devices->device_list_mutex);
7749
7750 return ret;
7751 }
7752
btrfs_dev_stat_inc_and_print(struct btrfs_device * dev,int index)7753 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
7754 {
7755 btrfs_dev_stat_inc(dev, index);
7756
7757 if (!dev->dev_stats_valid)
7758 return;
7759 btrfs_err_rl_in_rcu(dev->fs_info,
7760 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
7761 btrfs_dev_name(dev),
7762 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
7763 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
7764 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
7765 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
7766 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
7767 }
7768
btrfs_dev_stat_print_on_load(struct btrfs_device * dev)7769 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
7770 {
7771 int i;
7772
7773 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7774 if (btrfs_dev_stat_read(dev, i) != 0)
7775 break;
7776 if (i == BTRFS_DEV_STAT_VALUES_MAX)
7777 return; /* all values == 0, suppress message */
7778
7779 btrfs_info_in_rcu(dev->fs_info,
7780 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
7781 btrfs_dev_name(dev),
7782 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
7783 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
7784 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
7785 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
7786 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
7787 }
7788
btrfs_get_dev_stats(struct btrfs_fs_info * fs_info,struct btrfs_ioctl_get_dev_stats * stats)7789 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info,
7790 struct btrfs_ioctl_get_dev_stats *stats)
7791 {
7792 BTRFS_DEV_LOOKUP_ARGS(args);
7793 struct btrfs_device *dev;
7794 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7795 int i;
7796
7797 mutex_lock(&fs_devices->device_list_mutex);
7798 args.devid = stats->devid;
7799 dev = btrfs_find_device(fs_info->fs_devices, &args);
7800 mutex_unlock(&fs_devices->device_list_mutex);
7801
7802 if (!dev) {
7803 btrfs_warn(fs_info, "get dev_stats failed, device not found");
7804 return -ENODEV;
7805 } else if (!dev->dev_stats_valid) {
7806 btrfs_warn(fs_info, "get dev_stats failed, not yet valid");
7807 return -ENODEV;
7808 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
7809 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
7810 if (stats->nr_items > i)
7811 stats->values[i] =
7812 btrfs_dev_stat_read_and_reset(dev, i);
7813 else
7814 btrfs_dev_stat_set(dev, i, 0);
7815 }
7816 btrfs_info(fs_info, "device stats zeroed by %s (%d)",
7817 current->comm, task_pid_nr(current));
7818 } else {
7819 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7820 if (stats->nr_items > i)
7821 stats->values[i] = btrfs_dev_stat_read(dev, i);
7822 }
7823 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
7824 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
7825 return 0;
7826 }
7827
7828 /*
7829 * Update the size and bytes used for each device where it changed. This is
7830 * delayed since we would otherwise get errors while writing out the
7831 * superblocks.
7832 *
7833 * Must be invoked during transaction commit.
7834 */
btrfs_commit_device_sizes(struct btrfs_transaction * trans)7835 void btrfs_commit_device_sizes(struct btrfs_transaction *trans)
7836 {
7837 struct btrfs_device *curr, *next;
7838
7839 ASSERT(trans->state == TRANS_STATE_COMMIT_DOING);
7840
7841 if (list_empty(&trans->dev_update_list))
7842 return;
7843
7844 /*
7845 * We don't need the device_list_mutex here. This list is owned by the
7846 * transaction and the transaction must complete before the device is
7847 * released.
7848 */
7849 mutex_lock(&trans->fs_info->chunk_mutex);
7850 list_for_each_entry_safe(curr, next, &trans->dev_update_list,
7851 post_commit_list) {
7852 list_del_init(&curr->post_commit_list);
7853 curr->commit_total_bytes = curr->disk_total_bytes;
7854 curr->commit_bytes_used = curr->bytes_used;
7855 }
7856 mutex_unlock(&trans->fs_info->chunk_mutex);
7857 }
7858
7859 /*
7860 * Multiplicity factor for simple profiles: DUP, RAID1-like and RAID10.
7861 */
btrfs_bg_type_to_factor(u64 flags)7862 int btrfs_bg_type_to_factor(u64 flags)
7863 {
7864 const int index = btrfs_bg_flags_to_raid_index(flags);
7865
7866 return btrfs_raid_array[index].ncopies;
7867 }
7868
7869
7870
verify_one_dev_extent(struct btrfs_fs_info * fs_info,u64 chunk_offset,u64 devid,u64 physical_offset,u64 physical_len)7871 static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
7872 u64 chunk_offset, u64 devid,
7873 u64 physical_offset, u64 physical_len)
7874 {
7875 struct btrfs_dev_lookup_args args = { .devid = devid };
7876 struct btrfs_chunk_map *map;
7877 struct btrfs_device *dev;
7878 u64 stripe_len;
7879 bool found = false;
7880 int ret = 0;
7881 int i;
7882
7883 map = btrfs_find_chunk_map(fs_info, chunk_offset, 1);
7884 if (!map) {
7885 btrfs_err(fs_info,
7886 "dev extent physical offset %llu on devid %llu doesn't have corresponding chunk",
7887 physical_offset, devid);
7888 ret = -EUCLEAN;
7889 goto out;
7890 }
7891
7892 stripe_len = btrfs_calc_stripe_length(map);
7893 if (physical_len != stripe_len) {
7894 btrfs_err(fs_info,
7895 "dev extent physical offset %llu on devid %llu length doesn't match chunk %llu, have %llu expect %llu",
7896 physical_offset, devid, map->start, physical_len,
7897 stripe_len);
7898 ret = -EUCLEAN;
7899 goto out;
7900 }
7901
7902 /*
7903 * Very old mkfs.btrfs (before v4.1) will not respect the reserved
7904 * space. Although kernel can handle it without problem, better to warn
7905 * the users.
7906 */
7907 if (physical_offset < BTRFS_DEVICE_RANGE_RESERVED)
7908 btrfs_warn(fs_info,
7909 "devid %llu physical %llu len %llu inside the reserved space",
7910 devid, physical_offset, physical_len);
7911
7912 for (i = 0; i < map->num_stripes; i++) {
7913 if (map->stripes[i].dev->devid == devid &&
7914 map->stripes[i].physical == physical_offset) {
7915 found = true;
7916 if (map->verified_stripes >= map->num_stripes) {
7917 btrfs_err(fs_info,
7918 "too many dev extents for chunk %llu found",
7919 map->start);
7920 ret = -EUCLEAN;
7921 goto out;
7922 }
7923 map->verified_stripes++;
7924 break;
7925 }
7926 }
7927 if (!found) {
7928 btrfs_err(fs_info,
7929 "dev extent physical offset %llu devid %llu has no corresponding chunk",
7930 physical_offset, devid);
7931 ret = -EUCLEAN;
7932 }
7933
7934 /* Make sure no dev extent is beyond device boundary */
7935 dev = btrfs_find_device(fs_info->fs_devices, &args);
7936 if (!dev) {
7937 btrfs_err(fs_info, "failed to find devid %llu", devid);
7938 ret = -EUCLEAN;
7939 goto out;
7940 }
7941
7942 if (physical_offset + physical_len > dev->disk_total_bytes) {
7943 btrfs_err(fs_info,
7944 "dev extent devid %llu physical offset %llu len %llu is beyond device boundary %llu",
7945 devid, physical_offset, physical_len,
7946 dev->disk_total_bytes);
7947 ret = -EUCLEAN;
7948 goto out;
7949 }
7950
7951 if (dev->zone_info) {
7952 u64 zone_size = dev->zone_info->zone_size;
7953
7954 if (!IS_ALIGNED(physical_offset, zone_size) ||
7955 !IS_ALIGNED(physical_len, zone_size)) {
7956 btrfs_err(fs_info,
7957 "zoned: dev extent devid %llu physical offset %llu len %llu is not aligned to device zone",
7958 devid, physical_offset, physical_len);
7959 ret = -EUCLEAN;
7960 goto out;
7961 }
7962 }
7963
7964 out:
7965 btrfs_free_chunk_map(map);
7966 return ret;
7967 }
7968
verify_chunk_dev_extent_mapping(struct btrfs_fs_info * fs_info)7969 static int verify_chunk_dev_extent_mapping(struct btrfs_fs_info *fs_info)
7970 {
7971 struct rb_node *node;
7972 int ret = 0;
7973
7974 read_lock(&fs_info->mapping_tree_lock);
7975 for (node = rb_first_cached(&fs_info->mapping_tree); node; node = rb_next(node)) {
7976 struct btrfs_chunk_map *map;
7977
7978 map = rb_entry(node, struct btrfs_chunk_map, rb_node);
7979 if (map->num_stripes != map->verified_stripes) {
7980 btrfs_err(fs_info,
7981 "chunk %llu has missing dev extent, have %d expect %d",
7982 map->start, map->verified_stripes, map->num_stripes);
7983 ret = -EUCLEAN;
7984 goto out;
7985 }
7986 }
7987 out:
7988 read_unlock(&fs_info->mapping_tree_lock);
7989 return ret;
7990 }
7991
7992 /*
7993 * Ensure that all dev extents are mapped to correct chunk, otherwise
7994 * later chunk allocation/free would cause unexpected behavior.
7995 *
7996 * NOTE: This will iterate through the whole device tree, which should be of
7997 * the same size level as the chunk tree. This slightly increases mount time.
7998 */
btrfs_verify_dev_extents(struct btrfs_fs_info * fs_info)7999 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info)
8000 {
8001 struct btrfs_path *path;
8002 struct btrfs_root *root = fs_info->dev_root;
8003 struct btrfs_key key;
8004 u64 prev_devid = 0;
8005 u64 prev_dev_ext_end = 0;
8006 int ret = 0;
8007
8008 /*
8009 * We don't have a dev_root because we mounted with ignorebadroots and
8010 * failed to load the root, so we want to skip the verification in this
8011 * case for sure.
8012 *
8013 * However if the dev root is fine, but the tree itself is corrupted
8014 * we'd still fail to mount. This verification is only to make sure
8015 * writes can happen safely, so instead just bypass this check
8016 * completely in the case of IGNOREBADROOTS.
8017 */
8018 if (btrfs_test_opt(fs_info, IGNOREBADROOTS))
8019 return 0;
8020
8021 key.objectid = 1;
8022 key.type = BTRFS_DEV_EXTENT_KEY;
8023 key.offset = 0;
8024
8025 path = btrfs_alloc_path();
8026 if (!path)
8027 return -ENOMEM;
8028
8029 path->reada = READA_FORWARD;
8030 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
8031 if (ret < 0)
8032 goto out;
8033
8034 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
8035 ret = btrfs_next_leaf(root, path);
8036 if (ret < 0)
8037 goto out;
8038 /* No dev extents at all? Not good */
8039 if (ret > 0) {
8040 ret = -EUCLEAN;
8041 goto out;
8042 }
8043 }
8044 while (1) {
8045 struct extent_buffer *leaf = path->nodes[0];
8046 struct btrfs_dev_extent *dext;
8047 int slot = path->slots[0];
8048 u64 chunk_offset;
8049 u64 physical_offset;
8050 u64 physical_len;
8051 u64 devid;
8052
8053 btrfs_item_key_to_cpu(leaf, &key, slot);
8054 if (key.type != BTRFS_DEV_EXTENT_KEY)
8055 break;
8056 devid = key.objectid;
8057 physical_offset = key.offset;
8058
8059 dext = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent);
8060 chunk_offset = btrfs_dev_extent_chunk_offset(leaf, dext);
8061 physical_len = btrfs_dev_extent_length(leaf, dext);
8062
8063 /* Check if this dev extent overlaps with the previous one */
8064 if (devid == prev_devid && physical_offset < prev_dev_ext_end) {
8065 btrfs_err(fs_info,
8066 "dev extent devid %llu physical offset %llu overlap with previous dev extent end %llu",
8067 devid, physical_offset, prev_dev_ext_end);
8068 ret = -EUCLEAN;
8069 goto out;
8070 }
8071
8072 ret = verify_one_dev_extent(fs_info, chunk_offset, devid,
8073 physical_offset, physical_len);
8074 if (ret < 0)
8075 goto out;
8076 prev_devid = devid;
8077 prev_dev_ext_end = physical_offset + physical_len;
8078
8079 ret = btrfs_next_item(root, path);
8080 if (ret < 0)
8081 goto out;
8082 if (ret > 0) {
8083 ret = 0;
8084 break;
8085 }
8086 }
8087
8088 /* Ensure all chunks have corresponding dev extents */
8089 ret = verify_chunk_dev_extent_mapping(fs_info);
8090 out:
8091 btrfs_free_path(path);
8092 return ret;
8093 }
8094
8095 /*
8096 * Check whether the given block group or device is pinned by any inode being
8097 * used as a swapfile.
8098 */
btrfs_pinned_by_swapfile(struct btrfs_fs_info * fs_info,void * ptr)8099 bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr)
8100 {
8101 struct btrfs_swapfile_pin *sp;
8102 struct rb_node *node;
8103
8104 spin_lock(&fs_info->swapfile_pins_lock);
8105 node = fs_info->swapfile_pins.rb_node;
8106 while (node) {
8107 sp = rb_entry(node, struct btrfs_swapfile_pin, node);
8108 if (ptr < sp->ptr)
8109 node = node->rb_left;
8110 else if (ptr > sp->ptr)
8111 node = node->rb_right;
8112 else
8113 break;
8114 }
8115 spin_unlock(&fs_info->swapfile_pins_lock);
8116 return node != NULL;
8117 }
8118
relocating_repair_kthread(void * data)8119 static int relocating_repair_kthread(void *data)
8120 {
8121 struct btrfs_block_group *cache = data;
8122 struct btrfs_fs_info *fs_info = cache->fs_info;
8123 u64 target;
8124 int ret = 0;
8125
8126 target = cache->start;
8127 btrfs_put_block_group(cache);
8128
8129 sb_start_write(fs_info->sb);
8130 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
8131 btrfs_info(fs_info,
8132 "zoned: skip relocating block group %llu to repair: EBUSY",
8133 target);
8134 sb_end_write(fs_info->sb);
8135 return -EBUSY;
8136 }
8137
8138 mutex_lock(&fs_info->reclaim_bgs_lock);
8139
8140 /* Ensure block group still exists */
8141 cache = btrfs_lookup_block_group(fs_info, target);
8142 if (!cache)
8143 goto out;
8144
8145 if (!test_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags))
8146 goto out;
8147
8148 ret = btrfs_may_alloc_data_chunk(fs_info, target);
8149 if (ret < 0)
8150 goto out;
8151
8152 btrfs_info(fs_info,
8153 "zoned: relocating block group %llu to repair IO failure",
8154 target);
8155 ret = btrfs_relocate_chunk(fs_info, target);
8156
8157 out:
8158 if (cache)
8159 btrfs_put_block_group(cache);
8160 mutex_unlock(&fs_info->reclaim_bgs_lock);
8161 btrfs_exclop_finish(fs_info);
8162 sb_end_write(fs_info->sb);
8163
8164 return ret;
8165 }
8166
btrfs_repair_one_zone(struct btrfs_fs_info * fs_info,u64 logical)8167 bool btrfs_repair_one_zone(struct btrfs_fs_info *fs_info, u64 logical)
8168 {
8169 struct btrfs_block_group *cache;
8170
8171 if (!btrfs_is_zoned(fs_info))
8172 return false;
8173
8174 /* Do not attempt to repair in degraded state */
8175 if (btrfs_test_opt(fs_info, DEGRADED))
8176 return true;
8177
8178 cache = btrfs_lookup_block_group(fs_info, logical);
8179 if (!cache)
8180 return true;
8181
8182 if (test_and_set_bit(BLOCK_GROUP_FLAG_RELOCATING_REPAIR, &cache->runtime_flags)) {
8183 btrfs_put_block_group(cache);
8184 return true;
8185 }
8186
8187 kthread_run(relocating_repair_kthread, cache,
8188 "btrfs-relocating-repair");
8189
8190 return true;
8191 }
8192
map_raid56_repair_block(struct btrfs_io_context * bioc,struct btrfs_io_stripe * smap,u64 logical)8193 static void map_raid56_repair_block(struct btrfs_io_context *bioc,
8194 struct btrfs_io_stripe *smap,
8195 u64 logical)
8196 {
8197 int data_stripes = nr_bioc_data_stripes(bioc);
8198 int i;
8199
8200 for (i = 0; i < data_stripes; i++) {
8201 u64 stripe_start = bioc->full_stripe_logical +
8202 btrfs_stripe_nr_to_offset(i);
8203
8204 if (logical >= stripe_start &&
8205 logical < stripe_start + BTRFS_STRIPE_LEN)
8206 break;
8207 }
8208 ASSERT(i < data_stripes);
8209 smap->dev = bioc->stripes[i].dev;
8210 smap->physical = bioc->stripes[i].physical +
8211 ((logical - bioc->full_stripe_logical) &
8212 BTRFS_STRIPE_LEN_MASK);
8213 }
8214
8215 /*
8216 * Map a repair write into a single device.
8217 *
8218 * A repair write is triggered by read time repair or scrub, which would only
8219 * update the contents of a single device.
8220 * Not update any other mirrors nor go through RMW path.
8221 *
8222 * Callers should ensure:
8223 *
8224 * - Call btrfs_bio_counter_inc_blocked() first
8225 * - The range does not cross stripe boundary
8226 * - Has a valid @mirror_num passed in.
8227 */
btrfs_map_repair_block(struct btrfs_fs_info * fs_info,struct btrfs_io_stripe * smap,u64 logical,u32 length,int mirror_num)8228 int btrfs_map_repair_block(struct btrfs_fs_info *fs_info,
8229 struct btrfs_io_stripe *smap, u64 logical,
8230 u32 length, int mirror_num)
8231 {
8232 struct btrfs_io_context *bioc = NULL;
8233 u64 map_length = length;
8234 int mirror_ret = mirror_num;
8235 int ret;
8236
8237 ASSERT(mirror_num > 0);
8238
8239 ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical, &map_length,
8240 &bioc, smap, &mirror_ret);
8241 if (ret < 0)
8242 return ret;
8243
8244 /* The map range should not cross stripe boundary. */
8245 ASSERT(map_length >= length);
8246
8247 /* Already mapped to single stripe. */
8248 if (!bioc)
8249 goto out;
8250
8251 /* Map the RAID56 multi-stripe writes to a single one. */
8252 if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
8253 map_raid56_repair_block(bioc, smap, logical);
8254 goto out;
8255 }
8256
8257 ASSERT(mirror_num <= bioc->num_stripes);
8258 smap->dev = bioc->stripes[mirror_num - 1].dev;
8259 smap->physical = bioc->stripes[mirror_num - 1].physical;
8260 out:
8261 btrfs_put_bioc(bioc);
8262 ASSERT(smap->dev);
8263 return 0;
8264 }
8265