1 /* SPDX-License-Identifier: GPL-2.0 */
2
3 #ifndef BTRFS_BLOCK_GROUP_H
4 #define BTRFS_BLOCK_GROUP_H
5
6 #include <linux/atomic.h>
7 #include <linux/mutex.h>
8 #include <linux/list.h>
9 #include <linux/spinlock.h>
10 #include <linux/refcount.h>
11 #include <linux/wait.h>
12 #include <linux/sizes.h>
13 #include <linux/rwsem.h>
14 #include <linux/rbtree.h>
15 #include <uapi/linux/btrfs_tree.h>
16 #include "free-space-cache.h"
17
18 struct btrfs_chunk_map;
19 struct btrfs_fs_info;
20 struct btrfs_inode;
21 struct btrfs_trans_handle;
22
23 enum btrfs_disk_cache_state {
24 BTRFS_DC_WRITTEN,
25 BTRFS_DC_ERROR,
26 BTRFS_DC_CLEAR,
27 BTRFS_DC_SETUP,
28 };
29
30 enum btrfs_block_group_size_class {
31 /* Unset */
32 BTRFS_BG_SZ_NONE,
33 /* 0 < size <= 128K */
34 BTRFS_BG_SZ_SMALL,
35 /* 128K < size <= 8M */
36 BTRFS_BG_SZ_MEDIUM,
37 /* 8M < size < BG_LENGTH */
38 BTRFS_BG_SZ_LARGE,
39 };
40
41 /*
42 * This describes the state of the block_group for async discard. This is due
43 * to the two pass nature of it where extent discarding is prioritized over
44 * bitmap discarding. BTRFS_DISCARD_RESET_CURSOR is set when we are resetting
45 * between lists to prevent contention for discard state variables
46 * (eg. discard_cursor).
47 */
48 enum btrfs_discard_state {
49 BTRFS_DISCARD_EXTENTS,
50 BTRFS_DISCARD_BITMAPS,
51 BTRFS_DISCARD_RESET_CURSOR,
52 BTRFS_DISCARD_FULLY_REMAPPED,
53 };
54
55 /*
56 * Control flags for do_chunk_alloc's force field CHUNK_ALLOC_NO_FORCE means to
57 * only allocate a chunk if we really need one.
58 *
59 * CHUNK_ALLOC_LIMITED means to only try and allocate one if we have very few
60 * chunks already allocated. This is used as part of the clustering code to
61 * help make sure we have a good pool of storage to cluster in, without filling
62 * the FS with empty chunks
63 *
64 * CHUNK_ALLOC_FORCE means it must try to allocate one
65 *
66 * CHUNK_ALLOC_FORCE_FOR_EXTENT like CHUNK_ALLOC_FORCE but called from
67 * find_free_extent() that also activates the zone
68 */
69 enum btrfs_chunk_alloc_enum {
70 CHUNK_ALLOC_NO_FORCE,
71 CHUNK_ALLOC_LIMITED,
72 CHUNK_ALLOC_FORCE,
73 CHUNK_ALLOC_FORCE_FOR_EXTENT,
74 };
75
76 /* Block group flags set at runtime */
77 enum btrfs_block_group_flags {
78 BLOCK_GROUP_FLAG_IREF,
79 BLOCK_GROUP_FLAG_REMOVED,
80 BLOCK_GROUP_FLAG_TO_COPY,
81 BLOCK_GROUP_FLAG_RELOCATING_REPAIR,
82 BLOCK_GROUP_FLAG_CHUNK_ITEM_INSERTED,
83 BLOCK_GROUP_FLAG_ZONE_IS_ACTIVE,
84 BLOCK_GROUP_FLAG_ZONED_DATA_RELOC,
85 /* Does the block group need to be added to the free space tree? */
86 BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE,
87 /* Set after we add a new block group to the free space tree. */
88 BLOCK_GROUP_FLAG_FREE_SPACE_ADDED,
89 /* Indicate that the block group is placed on a sequential zone */
90 BLOCK_GROUP_FLAG_SEQUENTIAL_ZONE,
91 /*
92 * Indicate that block group is in the list of new block groups of a
93 * transaction.
94 */
95 BLOCK_GROUP_FLAG_NEW,
96 BLOCK_GROUP_FLAG_FULLY_REMAPPED,
97 BLOCK_GROUP_FLAG_STRIPE_REMOVAL_PENDING,
98 };
99
100 enum btrfs_caching_type {
101 BTRFS_CACHE_NO,
102 BTRFS_CACHE_STARTED,
103 BTRFS_CACHE_FINISHED,
104 BTRFS_CACHE_ERROR,
105 };
106
107 struct btrfs_caching_control {
108 struct list_head list;
109 struct mutex mutex;
110 wait_queue_head_t wait;
111 struct btrfs_work work;
112 struct btrfs_block_group *block_group;
113 /* Track progress of caching during allocation. */
114 atomic_t progress;
115 refcount_t count;
116 };
117
118 /* Once caching_thread() finds this much free space, it will wake up waiters. */
119 #define CACHING_CTL_WAKE_UP SZ_2M
120
121 struct btrfs_block_group {
122 struct btrfs_fs_info *fs_info;
123 struct btrfs_inode *inode;
124 spinlock_t lock;
125 u64 start;
126 u64 length;
127 u64 pinned;
128 u64 reserved;
129 u64 used;
130 u64 delalloc_bytes;
131 u64 bytes_super;
132 u64 flags;
133 u64 cache_generation;
134 u64 global_root_id;
135 u64 remap_bytes;
136 u32 identity_remap_count;
137
138 /*
139 * The last committed used bytes of this block group, if the above @used
140 * is still the same as @last_used, we don't need to update block
141 * group item of this block group.
142 */
143 u64 last_used;
144 /* The last committed remap_bytes value of this block group. */
145 u64 last_remap_bytes;
146 /* The last commited identity_remap_count value of this block group. */
147 u32 last_identity_remap_count;
148 /* The last committed flags value for this block group. */
149 u64 last_flags;
150
151 /*
152 * If the free space extent count exceeds this number, convert the block
153 * group to bitmaps.
154 */
155 u32 bitmap_high_thresh;
156
157 /*
158 * If the free space extent count drops below this number, convert the
159 * block group back to extents.
160 */
161 u32 bitmap_low_thresh;
162
163 /*
164 * It is just used for the delayed data space allocation because
165 * only the data space allocation and the relative metadata update
166 * can be done cross the transaction.
167 */
168 struct rw_semaphore data_rwsem;
169
170 /* For raid56, this is a full stripe, without parity */
171 unsigned long full_stripe_len;
172 unsigned long runtime_flags;
173
174 unsigned int ro;
175
176 int disk_cache_state;
177
178 /* Cache tracking stuff */
179 int cached;
180 struct btrfs_caching_control *caching_ctl;
181
182 struct btrfs_space_info *space_info;
183
184 /* Free space cache stuff */
185 struct btrfs_free_space_ctl *free_space_ctl;
186
187 /* Block group cache stuff */
188 struct rb_node cache_node;
189
190 /* For block groups in the same raid type */
191 struct list_head list;
192
193 refcount_t refs;
194
195 /*
196 * List of struct btrfs_free_clusters for this block group.
197 * Today it will only have one thing on it, but that may change
198 */
199 struct list_head cluster_list;
200
201 /*
202 * Used for several lists:
203 *
204 * 1) struct btrfs_fs_info::unused_bgs
205 * 2) struct btrfs_fs_info::reclaim_bgs
206 * 3) struct btrfs_transaction::deleted_bgs
207 * 4) struct btrfs_trans_handle::new_bgs
208 */
209 struct list_head bg_list;
210
211 /* For read-only block groups */
212 struct list_head ro_list;
213
214 /*
215 * When non-zero it means the block group's logical address and its
216 * device extents can not be reused for future block group allocations
217 * until the counter goes down to 0. This is to prevent them from being
218 * reused while some task is still using the block group after it was
219 * deleted - we want to make sure they can only be reused for new block
220 * groups after that task is done with the deleted block group.
221 */
222 atomic_t frozen;
223
224 /* For discard operations */
225 struct list_head discard_list;
226 int discard_index;
227 u64 discard_eligible_time;
228 u64 discard_cursor;
229 enum btrfs_discard_state discard_state;
230
231 /* For dirty block groups */
232 struct list_head dirty_list;
233 struct list_head io_list;
234
235 struct btrfs_io_ctl io_ctl;
236
237 /*
238 * Incremented when doing extent allocations and holding a read lock
239 * on the space_info's groups_sem semaphore.
240 * Decremented when an ordered extent that represents an IO against this
241 * block group's range is created (after it's added to its inode's
242 * root's list of ordered extents) or immediately after the allocation
243 * if it's a metadata extent or fallocate extent (for these cases we
244 * don't create ordered extents).
245 */
246 atomic_t reservations;
247
248 /*
249 * Incremented while holding the spinlock *lock* by a task checking if
250 * it can perform a nocow write (incremented if the value for the *ro*
251 * field is 0). Decremented by such tasks once they create an ordered
252 * extent or before that if some error happens before reaching that step.
253 * This is to prevent races between block group relocation and nocow
254 * writes through direct IO.
255 */
256 atomic_t nocow_writers;
257
258 /* Lock for free space tree operations. */
259 struct mutex free_space_lock;
260
261 /* Protected by @free_space_lock. */
262 bool using_free_space_bitmaps;
263 /* Protected by @free_space_lock. */
264 bool using_free_space_bitmaps_cached;
265
266 /*
267 * Number of extents in this block group used for swap files.
268 * All accesses protected by the spinlock 'lock'.
269 */
270 int swap_extents;
271
272 /*
273 * Allocation offset for the block group to implement sequential
274 * allocation. This is used only on a zoned filesystem.
275 */
276 u64 alloc_offset;
277 u64 zone_unusable;
278 u64 zone_capacity;
279 u64 meta_write_pointer;
280 struct btrfs_chunk_map *physical_map;
281 struct list_head active_bg_list;
282 struct work_struct zone_finish_work;
283 struct extent_buffer *last_eb;
284 enum btrfs_block_group_size_class size_class;
285 u64 reclaim_mark;
286 };
287
btrfs_block_group_end(const struct btrfs_block_group * block_group)288 static inline u64 btrfs_block_group_end(const struct btrfs_block_group *block_group)
289 {
290 return (block_group->start + block_group->length);
291 }
292
btrfs_is_block_group_used(const struct btrfs_block_group * bg)293 static inline bool btrfs_is_block_group_used(const struct btrfs_block_group *bg)
294 {
295 lockdep_assert_held(&bg->lock);
296
297 return (bg->used > 0 || bg->reserved > 0 || bg->pinned > 0 ||
298 bg->remap_bytes > 0);
299 }
300
btrfs_is_block_group_data_only(const struct btrfs_block_group * block_group)301 static inline bool btrfs_is_block_group_data_only(const struct btrfs_block_group *block_group)
302 {
303 /*
304 * In mixed mode the fragmentation is expected to be high, lowering the
305 * efficiency, so only proper data block groups are considered.
306 */
307 return (block_group->flags & BTRFS_BLOCK_GROUP_DATA) &&
308 !(block_group->flags & BTRFS_BLOCK_GROUP_METADATA);
309 }
310
btrfs_block_group_available_space(const struct btrfs_block_group * bg)311 static inline u64 btrfs_block_group_available_space(const struct btrfs_block_group *bg)
312 {
313 lockdep_assert_held(&bg->lock);
314
315 return (bg->length - bg->used - bg->pinned - bg->reserved -
316 bg->bytes_super - bg->zone_unusable);
317 }
318
319 #ifdef CONFIG_BTRFS_DEBUG
320 int btrfs_should_fragment_free_space(const struct btrfs_block_group *block_group);
321 #endif
322
323 struct btrfs_block_group *btrfs_lookup_first_block_group(
324 struct btrfs_fs_info *info, u64 bytenr);
325 struct btrfs_block_group *btrfs_lookup_block_group(
326 struct btrfs_fs_info *info, u64 bytenr);
327 struct btrfs_block_group *btrfs_next_block_group(
328 struct btrfs_block_group *cache);
329 void btrfs_get_block_group(struct btrfs_block_group *cache);
330 void btrfs_put_block_group(struct btrfs_block_group *cache);
331 void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,
332 const u64 start);
333 void btrfs_wait_block_group_reservations(struct btrfs_block_group *bg);
334 struct btrfs_block_group *btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info,
335 u64 bytenr);
336 void btrfs_dec_nocow_writers(struct btrfs_block_group *bg);
337 void btrfs_wait_nocow_writers(struct btrfs_block_group *bg);
338 void btrfs_wait_block_group_cache_progress(struct btrfs_block_group *cache,
339 u64 num_bytes);
340 int btrfs_cache_block_group(struct btrfs_block_group *cache, bool wait);
341 struct btrfs_caching_control *btrfs_get_caching_control(
342 struct btrfs_block_group *cache);
343 int btrfs_add_new_free_space(struct btrfs_block_group *block_group,
344 u64 start, u64 end, u64 *total_added_ret);
345 struct btrfs_trans_handle *btrfs_start_trans_remove_block_group(
346 struct btrfs_fs_info *fs_info,
347 const u64 chunk_offset);
348 void btrfs_remove_bg_from_sinfo(struct btrfs_block_group *bg);
349 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
350 struct btrfs_chunk_map *map);
351 void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info);
352 void btrfs_mark_bg_unused(struct btrfs_block_group *bg);
353 void btrfs_reclaim_bgs_work(struct work_struct *work);
354 void btrfs_reclaim_bgs(struct btrfs_fs_info *fs_info);
355 void btrfs_mark_bg_to_reclaim(struct btrfs_block_group *bg);
356 int btrfs_read_block_groups(struct btrfs_fs_info *info);
357 struct btrfs_block_group *btrfs_make_block_group(struct btrfs_trans_handle *trans,
358 struct btrfs_space_info *space_info,
359 u64 type, u64 chunk_offset, u64 size);
360 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans);
361 int btrfs_inc_block_group_ro(struct btrfs_block_group *cache,
362 bool do_chunk_alloc);
363 void btrfs_dec_block_group_ro(struct btrfs_block_group *cache);
364 int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans);
365 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans);
366 int btrfs_setup_space_cache(struct btrfs_trans_handle *trans);
367 int btrfs_update_block_group(struct btrfs_trans_handle *trans,
368 u64 bytenr, u64 num_bytes, bool alloc);
369 int btrfs_add_reserved_bytes(struct btrfs_block_group *cache,
370 u64 ram_bytes, u64 num_bytes, bool delalloc,
371 bool force_wrong_size_class);
372 void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, u64 num_bytes,
373 bool is_delalloc);
374 int btrfs_chunk_alloc(struct btrfs_trans_handle *trans,
375 struct btrfs_space_info *space_info, u64 flags,
376 enum btrfs_chunk_alloc_enum force);
377 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans, u64 type);
378 void check_system_chunk(struct btrfs_trans_handle *trans, const u64 type);
379 void btrfs_reserve_chunk_metadata(struct btrfs_trans_handle *trans,
380 bool is_item_insertion);
381 u64 btrfs_get_alloc_profile(struct btrfs_fs_info *fs_info, u64 orig_flags);
382 void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
383 int btrfs_free_block_groups(struct btrfs_fs_info *info);
384 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
385 u64 physical, u64 **logical, int *naddrs, int *stripe_len);
386
btrfs_data_alloc_profile(struct btrfs_fs_info * fs_info)387 static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)
388 {
389 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_DATA);
390 }
391
btrfs_metadata_alloc_profile(struct btrfs_fs_info * fs_info)392 static inline u64 btrfs_metadata_alloc_profile(struct btrfs_fs_info *fs_info)
393 {
394 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_METADATA);
395 }
396
btrfs_system_alloc_profile(struct btrfs_fs_info * fs_info)397 static inline u64 btrfs_system_alloc_profile(struct btrfs_fs_info *fs_info)
398 {
399 return btrfs_get_alloc_profile(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
400 }
401
btrfs_block_group_done(const struct btrfs_block_group * cache)402 static inline int btrfs_block_group_done(const struct btrfs_block_group *cache)
403 {
404 smp_mb();
405 return cache->cached == BTRFS_CACHE_FINISHED ||
406 cache->cached == BTRFS_CACHE_ERROR;
407 }
408
409 void btrfs_freeze_block_group(struct btrfs_block_group *cache);
410 void btrfs_unfreeze_block_group(struct btrfs_block_group *cache);
411
412 bool btrfs_inc_block_group_swap_extents(struct btrfs_block_group *bg);
413 void btrfs_dec_block_group_swap_extents(struct btrfs_block_group *bg, int amount);
414
415 enum btrfs_block_group_size_class btrfs_calc_block_group_size_class(u64 size);
416 int btrfs_use_block_group_size_class(struct btrfs_block_group *bg,
417 enum btrfs_block_group_size_class size_class,
418 bool force_wrong_size_class);
419 bool btrfs_block_group_should_use_size_class(const struct btrfs_block_group *bg);
420 void btrfs_mark_bg_fully_remapped(struct btrfs_block_group *bg,
421 struct btrfs_trans_handle *trans);
422 int btrfs_populate_fully_remapped_bgs_list(struct btrfs_fs_info *fs_info);
423
424 #endif /* BTRFS_BLOCK_GROUP_H */
425