1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4 * Horst Hummel <Horst.Hummel@de.ibm.com>
5 * Carsten Otte <Cotte@de.ibm.com>
6 * Martin Schwidefsky <schwidefsky@de.ibm.com>
7 * Bugreports.to..: <Linux390@de.ibm.com>
8 * Copyright IBM Corp. 1999, 2009
9 */
10
11 #define KMSG_COMPONENT "dasd"
12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14 #include <linux/kmod.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/ctype.h>
18 #include <linux/major.h>
19 #include <linux/slab.h>
20 #include <linux/hdreg.h>
21 #include <linux/async.h>
22 #include <linux/mutex.h>
23 #include <linux/debugfs.h>
24 #include <linux/seq_file.h>
25 #include <linux/vmalloc.h>
26
27 #include <asm/ccwdev.h>
28 #include <asm/ebcdic.h>
29 #include <asm/idals.h>
30 #include <asm/itcw.h>
31 #include <asm/diag.h>
32
33 /* This is ugly... */
34 #define PRINTK_HEADER "dasd:"
35
36 #include "dasd_int.h"
37 /*
38 * SECTION: Constant definitions to be used within this file
39 */
40 #define DASD_CHANQ_MAX_SIZE 4
41
42 #define DASD_DIAG_MOD "dasd_diag_mod"
43
44 /*
45 * SECTION: exported variables of dasd.c
46 */
47 debug_info_t *dasd_debug_area;
48 EXPORT_SYMBOL(dasd_debug_area);
49 static struct dentry *dasd_debugfs_root_entry;
50 struct dasd_discipline *dasd_diag_discipline_pointer;
51 EXPORT_SYMBOL(dasd_diag_discipline_pointer);
52 void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
53
54 MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>");
55 MODULE_DESCRIPTION("Linux on S/390 DASD device driver,"
56 " Copyright IBM Corp. 2000");
57 MODULE_LICENSE("GPL");
58
59 /*
60 * SECTION: prototypes for static functions of dasd.c
61 */
62 static int dasd_flush_block_queue(struct dasd_block *);
63 static void dasd_device_tasklet(unsigned long);
64 static void dasd_block_tasklet(unsigned long);
65 static void do_kick_device(struct work_struct *);
66 static void do_reload_device(struct work_struct *);
67 static void do_requeue_requests(struct work_struct *);
68 static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
69 static void dasd_device_timeout(struct timer_list *);
70 static void dasd_block_timeout(struct timer_list *);
71 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
72 static void dasd_profile_init(struct dasd_profile *, struct dentry *);
73 static void dasd_profile_exit(struct dasd_profile *);
74 static void dasd_hosts_init(struct dentry *, struct dasd_device *);
75 static void dasd_hosts_exit(struct dasd_device *);
76 static int dasd_handle_autoquiesce(struct dasd_device *, struct dasd_ccw_req *,
77 unsigned int);
78 /*
79 * SECTION: Operations on the device structure.
80 */
81 static wait_queue_head_t dasd_init_waitq;
82 static wait_queue_head_t dasd_flush_wq;
83 static wait_queue_head_t generic_waitq;
84 static wait_queue_head_t shutdown_waitq;
85
86 /*
87 * Allocate memory for a new device structure.
88 */
dasd_alloc_device(void)89 struct dasd_device *dasd_alloc_device(void)
90 {
91 struct dasd_device *device;
92
93 device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
94 if (!device)
95 return ERR_PTR(-ENOMEM);
96
97 /* Get two pages for normal block device operations. */
98 device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
99 if (!device->ccw_mem) {
100 kfree(device);
101 return ERR_PTR(-ENOMEM);
102 }
103 /* Get one page for error recovery. */
104 device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
105 if (!device->erp_mem) {
106 free_pages((unsigned long) device->ccw_mem, 1);
107 kfree(device);
108 return ERR_PTR(-ENOMEM);
109 }
110 /* Get two pages for ese format. */
111 device->ese_mem = (void *)__get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
112 if (!device->ese_mem) {
113 free_page((unsigned long) device->erp_mem);
114 free_pages((unsigned long) device->ccw_mem, 1);
115 kfree(device);
116 return ERR_PTR(-ENOMEM);
117 }
118
119 dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
120 dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
121 dasd_init_chunklist(&device->ese_chunks, device->ese_mem, PAGE_SIZE * 2);
122 spin_lock_init(&device->mem_lock);
123 atomic_set(&device->tasklet_scheduled, 0);
124 tasklet_init(&device->tasklet, dasd_device_tasklet,
125 (unsigned long) device);
126 INIT_LIST_HEAD(&device->ccw_queue);
127 timer_setup(&device->timer, dasd_device_timeout, 0);
128 INIT_WORK(&device->kick_work, do_kick_device);
129 INIT_WORK(&device->reload_device, do_reload_device);
130 INIT_WORK(&device->requeue_requests, do_requeue_requests);
131 device->state = DASD_STATE_NEW;
132 device->target = DASD_STATE_NEW;
133 mutex_init(&device->state_mutex);
134 spin_lock_init(&device->profile.lock);
135 return device;
136 }
137
138 /*
139 * Free memory of a device structure.
140 */
dasd_free_device(struct dasd_device * device)141 void dasd_free_device(struct dasd_device *device)
142 {
143 kfree(device->private);
144 free_pages((unsigned long) device->ese_mem, 1);
145 free_page((unsigned long) device->erp_mem);
146 free_pages((unsigned long) device->ccw_mem, 1);
147 kfree(device);
148 }
149
150 /*
151 * Allocate memory for a new device structure.
152 */
dasd_alloc_block(void)153 struct dasd_block *dasd_alloc_block(void)
154 {
155 struct dasd_block *block;
156
157 block = kzalloc(sizeof(*block), GFP_ATOMIC);
158 if (!block)
159 return ERR_PTR(-ENOMEM);
160 /* open_count = 0 means device online but not in use */
161 atomic_set(&block->open_count, -1);
162
163 atomic_set(&block->tasklet_scheduled, 0);
164 tasklet_init(&block->tasklet, dasd_block_tasklet,
165 (unsigned long) block);
166 INIT_LIST_HEAD(&block->ccw_queue);
167 spin_lock_init(&block->queue_lock);
168 INIT_LIST_HEAD(&block->format_list);
169 spin_lock_init(&block->format_lock);
170 timer_setup(&block->timer, dasd_block_timeout, 0);
171 spin_lock_init(&block->profile.lock);
172
173 return block;
174 }
175 EXPORT_SYMBOL_GPL(dasd_alloc_block);
176
177 /*
178 * Free memory of a device structure.
179 */
dasd_free_block(struct dasd_block * block)180 void dasd_free_block(struct dasd_block *block)
181 {
182 kfree(block);
183 }
184 EXPORT_SYMBOL_GPL(dasd_free_block);
185
186 /*
187 * Make a new device known to the system.
188 */
dasd_state_new_to_known(struct dasd_device * device)189 static int dasd_state_new_to_known(struct dasd_device *device)
190 {
191 /*
192 * As long as the device is not in state DASD_STATE_NEW we want to
193 * keep the reference count > 0.
194 */
195 dasd_get_device(device);
196 device->state = DASD_STATE_KNOWN;
197 return 0;
198 }
199
200 /*
201 * Let the system forget about a device.
202 */
dasd_state_known_to_new(struct dasd_device * device)203 static int dasd_state_known_to_new(struct dasd_device *device)
204 {
205 /* Disable extended error reporting for this device. */
206 dasd_eer_disable(device);
207 device->state = DASD_STATE_NEW;
208
209 /* Give up reference we took in dasd_state_new_to_known. */
210 dasd_put_device(device);
211 return 0;
212 }
213
dasd_debugfs_setup(const char * name,struct dentry * base_dentry)214 static struct dentry *dasd_debugfs_setup(const char *name,
215 struct dentry *base_dentry)
216 {
217 struct dentry *pde;
218
219 if (!base_dentry)
220 return NULL;
221 pde = debugfs_create_dir(name, base_dentry);
222 if (!pde || IS_ERR(pde))
223 return NULL;
224 return pde;
225 }
226
227 /*
228 * Request the irq line for the device.
229 */
dasd_state_known_to_basic(struct dasd_device * device)230 static int dasd_state_known_to_basic(struct dasd_device *device)
231 {
232 struct dasd_block *block = device->block;
233 int rc = 0;
234
235 /* Allocate and register gendisk structure. */
236 if (block) {
237 rc = dasd_gendisk_alloc(block);
238 if (rc)
239 return rc;
240 block->debugfs_dentry =
241 dasd_debugfs_setup(block->gdp->disk_name,
242 dasd_debugfs_root_entry);
243 dasd_profile_init(&block->profile, block->debugfs_dentry);
244 if (dasd_global_profile_level == DASD_PROFILE_ON)
245 dasd_profile_on(&device->block->profile);
246 }
247 device->debugfs_dentry =
248 dasd_debugfs_setup(dev_name(&device->cdev->dev),
249 dasd_debugfs_root_entry);
250 dasd_profile_init(&device->profile, device->debugfs_dentry);
251 dasd_hosts_init(device->debugfs_dentry, device);
252
253 /* register 'device' debug area, used for all DBF_DEV_XXX calls */
254 device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
255 8 * sizeof(long));
256 debug_register_view(device->debug_area, &debug_sprintf_view);
257 debug_set_level(device->debug_area, DBF_WARNING);
258 DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
259
260 device->state = DASD_STATE_BASIC;
261
262 return rc;
263 }
264
265 /*
266 * Release the irq line for the device. Terminate any running i/o.
267 */
dasd_state_basic_to_known(struct dasd_device * device)268 static int dasd_state_basic_to_known(struct dasd_device *device)
269 {
270 int rc;
271
272 if (device->discipline->basic_to_known) {
273 rc = device->discipline->basic_to_known(device);
274 if (rc)
275 return rc;
276 }
277
278 if (device->block) {
279 dasd_profile_exit(&device->block->profile);
280 debugfs_remove(device->block->debugfs_dentry);
281 dasd_gendisk_free(device->block);
282 dasd_block_clear_timer(device->block);
283 }
284 rc = dasd_flush_device_queue(device);
285 if (rc)
286 return rc;
287 dasd_device_clear_timer(device);
288 dasd_profile_exit(&device->profile);
289 dasd_hosts_exit(device);
290 debugfs_remove(device->debugfs_dentry);
291 DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
292 if (device->debug_area != NULL) {
293 debug_unregister(device->debug_area);
294 device->debug_area = NULL;
295 }
296 device->state = DASD_STATE_KNOWN;
297 return 0;
298 }
299
300 /*
301 * Do the initial analysis. The do_analysis function may return
302 * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
303 * until the discipline decides to continue the startup sequence
304 * by calling the function dasd_change_state. The eckd disciplines
305 * uses this to start a ccw that detects the format. The completion
306 * interrupt for this detection ccw uses the kernel event daemon to
307 * trigger the call to dasd_change_state. All this is done in the
308 * discipline code, see dasd_eckd.c.
309 * After the analysis ccw is done (do_analysis returned 0) the block
310 * device is setup.
311 * In case the analysis returns an error, the device setup is stopped
312 * (a fake disk was already added to allow formatting).
313 */
dasd_state_basic_to_ready(struct dasd_device * device)314 static int dasd_state_basic_to_ready(struct dasd_device *device)
315 {
316 int rc;
317 struct dasd_block *block;
318 struct gendisk *disk;
319
320 rc = 0;
321 block = device->block;
322 /* make disk known with correct capacity */
323 if (block) {
324 if (block->base->discipline->do_analysis != NULL)
325 rc = block->base->discipline->do_analysis(block);
326 if (rc) {
327 if (rc != -EAGAIN) {
328 device->state = DASD_STATE_UNFMT;
329 disk = device->block->gdp;
330 kobject_uevent(&disk_to_dev(disk)->kobj,
331 KOBJ_CHANGE);
332 goto out;
333 }
334 return rc;
335 }
336 if (device->discipline->setup_blk_queue)
337 device->discipline->setup_blk_queue(block);
338 set_capacity(block->gdp,
339 block->blocks << block->s2b_shift);
340 device->state = DASD_STATE_READY;
341 rc = dasd_scan_partitions(block);
342 if (rc) {
343 device->state = DASD_STATE_BASIC;
344 return rc;
345 }
346 } else {
347 device->state = DASD_STATE_READY;
348 }
349 out:
350 if (device->discipline->basic_to_ready)
351 rc = device->discipline->basic_to_ready(device);
352 return rc;
353 }
354
355 static inline
_wait_for_empty_queues(struct dasd_device * device)356 int _wait_for_empty_queues(struct dasd_device *device)
357 {
358 if (device->block)
359 return list_empty(&device->ccw_queue) &&
360 list_empty(&device->block->ccw_queue);
361 else
362 return list_empty(&device->ccw_queue);
363 }
364
365 /*
366 * Remove device from block device layer. Destroy dirty buffers.
367 * Forget format information. Check if the target level is basic
368 * and if it is create fake disk for formatting.
369 */
dasd_state_ready_to_basic(struct dasd_device * device)370 static int dasd_state_ready_to_basic(struct dasd_device *device)
371 {
372 int rc;
373
374 device->state = DASD_STATE_BASIC;
375 if (device->block) {
376 struct dasd_block *block = device->block;
377 rc = dasd_flush_block_queue(block);
378 if (rc) {
379 device->state = DASD_STATE_READY;
380 return rc;
381 }
382 dasd_destroy_partitions(block);
383 block->blocks = 0;
384 block->bp_block = 0;
385 block->s2b_shift = 0;
386 }
387 return 0;
388 }
389
390 /*
391 * Back to basic.
392 */
dasd_state_unfmt_to_basic(struct dasd_device * device)393 static int dasd_state_unfmt_to_basic(struct dasd_device *device)
394 {
395 device->state = DASD_STATE_BASIC;
396 return 0;
397 }
398
399 /*
400 * Make the device online and schedule the bottom half to start
401 * the requeueing of requests from the linux request queue to the
402 * ccw queue.
403 */
404 static int
dasd_state_ready_to_online(struct dasd_device * device)405 dasd_state_ready_to_online(struct dasd_device * device)
406 {
407 device->state = DASD_STATE_ONLINE;
408 if (device->block) {
409 dasd_schedule_block_bh(device->block);
410 if ((device->features & DASD_FEATURE_USERAW)) {
411 kobject_uevent(&disk_to_dev(device->block->gdp)->kobj,
412 KOBJ_CHANGE);
413 return 0;
414 }
415 disk_uevent(device->block->bdev_handle->bdev->bd_disk,
416 KOBJ_CHANGE);
417 }
418 return 0;
419 }
420
421 /*
422 * Stop the requeueing of requests again.
423 */
dasd_state_online_to_ready(struct dasd_device * device)424 static int dasd_state_online_to_ready(struct dasd_device *device)
425 {
426 int rc;
427
428 if (device->discipline->online_to_ready) {
429 rc = device->discipline->online_to_ready(device);
430 if (rc)
431 return rc;
432 }
433
434 device->state = DASD_STATE_READY;
435 if (device->block && !(device->features & DASD_FEATURE_USERAW))
436 disk_uevent(device->block->bdev_handle->bdev->bd_disk,
437 KOBJ_CHANGE);
438 return 0;
439 }
440
441 /*
442 * Device startup state changes.
443 */
dasd_increase_state(struct dasd_device * device)444 static int dasd_increase_state(struct dasd_device *device)
445 {
446 int rc;
447
448 rc = 0;
449 if (device->state == DASD_STATE_NEW &&
450 device->target >= DASD_STATE_KNOWN)
451 rc = dasd_state_new_to_known(device);
452
453 if (!rc &&
454 device->state == DASD_STATE_KNOWN &&
455 device->target >= DASD_STATE_BASIC)
456 rc = dasd_state_known_to_basic(device);
457
458 if (!rc &&
459 device->state == DASD_STATE_BASIC &&
460 device->target >= DASD_STATE_READY)
461 rc = dasd_state_basic_to_ready(device);
462
463 if (!rc &&
464 device->state == DASD_STATE_UNFMT &&
465 device->target > DASD_STATE_UNFMT)
466 rc = -EPERM;
467
468 if (!rc &&
469 device->state == DASD_STATE_READY &&
470 device->target >= DASD_STATE_ONLINE)
471 rc = dasd_state_ready_to_online(device);
472
473 return rc;
474 }
475
476 /*
477 * Device shutdown state changes.
478 */
dasd_decrease_state(struct dasd_device * device)479 static int dasd_decrease_state(struct dasd_device *device)
480 {
481 int rc;
482
483 rc = 0;
484 if (device->state == DASD_STATE_ONLINE &&
485 device->target <= DASD_STATE_READY)
486 rc = dasd_state_online_to_ready(device);
487
488 if (!rc &&
489 device->state == DASD_STATE_READY &&
490 device->target <= DASD_STATE_BASIC)
491 rc = dasd_state_ready_to_basic(device);
492
493 if (!rc &&
494 device->state == DASD_STATE_UNFMT &&
495 device->target <= DASD_STATE_BASIC)
496 rc = dasd_state_unfmt_to_basic(device);
497
498 if (!rc &&
499 device->state == DASD_STATE_BASIC &&
500 device->target <= DASD_STATE_KNOWN)
501 rc = dasd_state_basic_to_known(device);
502
503 if (!rc &&
504 device->state == DASD_STATE_KNOWN &&
505 device->target <= DASD_STATE_NEW)
506 rc = dasd_state_known_to_new(device);
507
508 return rc;
509 }
510
511 /*
512 * This is the main startup/shutdown routine.
513 */
dasd_change_state(struct dasd_device * device)514 static void dasd_change_state(struct dasd_device *device)
515 {
516 int rc;
517
518 if (device->state == device->target)
519 /* Already where we want to go today... */
520 return;
521 if (device->state < device->target)
522 rc = dasd_increase_state(device);
523 else
524 rc = dasd_decrease_state(device);
525 if (rc == -EAGAIN)
526 return;
527 if (rc)
528 device->target = device->state;
529
530 /* let user-space know that the device status changed */
531 kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
532
533 if (device->state == device->target)
534 wake_up(&dasd_init_waitq);
535 }
536
537 /*
538 * Kick starter for devices that did not complete the startup/shutdown
539 * procedure or were sleeping because of a pending state.
540 * dasd_kick_device will schedule a call do do_kick_device to the kernel
541 * event daemon.
542 */
do_kick_device(struct work_struct * work)543 static void do_kick_device(struct work_struct *work)
544 {
545 struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
546 mutex_lock(&device->state_mutex);
547 dasd_change_state(device);
548 mutex_unlock(&device->state_mutex);
549 dasd_schedule_device_bh(device);
550 dasd_put_device(device);
551 }
552
dasd_kick_device(struct dasd_device * device)553 void dasd_kick_device(struct dasd_device *device)
554 {
555 dasd_get_device(device);
556 /* queue call to dasd_kick_device to the kernel event daemon. */
557 if (!schedule_work(&device->kick_work))
558 dasd_put_device(device);
559 }
560 EXPORT_SYMBOL(dasd_kick_device);
561
562 /*
563 * dasd_reload_device will schedule a call do do_reload_device to the kernel
564 * event daemon.
565 */
do_reload_device(struct work_struct * work)566 static void do_reload_device(struct work_struct *work)
567 {
568 struct dasd_device *device = container_of(work, struct dasd_device,
569 reload_device);
570 device->discipline->reload(device);
571 dasd_put_device(device);
572 }
573
dasd_reload_device(struct dasd_device * device)574 void dasd_reload_device(struct dasd_device *device)
575 {
576 dasd_get_device(device);
577 /* queue call to dasd_reload_device to the kernel event daemon. */
578 if (!schedule_work(&device->reload_device))
579 dasd_put_device(device);
580 }
581 EXPORT_SYMBOL(dasd_reload_device);
582
583 /*
584 * Set the target state for a device and starts the state change.
585 */
dasd_set_target_state(struct dasd_device * device,int target)586 void dasd_set_target_state(struct dasd_device *device, int target)
587 {
588 dasd_get_device(device);
589 mutex_lock(&device->state_mutex);
590 /* If we are in probeonly mode stop at DASD_STATE_READY. */
591 if (dasd_probeonly && target > DASD_STATE_READY)
592 target = DASD_STATE_READY;
593 if (device->target != target) {
594 if (device->state == target)
595 wake_up(&dasd_init_waitq);
596 device->target = target;
597 }
598 if (device->state != device->target)
599 dasd_change_state(device);
600 mutex_unlock(&device->state_mutex);
601 dasd_put_device(device);
602 }
603
604 /*
605 * Enable devices with device numbers in [from..to].
606 */
_wait_for_device(struct dasd_device * device)607 static inline int _wait_for_device(struct dasd_device *device)
608 {
609 return (device->state == device->target);
610 }
611
dasd_enable_device(struct dasd_device * device)612 void dasd_enable_device(struct dasd_device *device)
613 {
614 dasd_set_target_state(device, DASD_STATE_ONLINE);
615 if (device->state <= DASD_STATE_KNOWN)
616 /* No discipline for device found. */
617 dasd_set_target_state(device, DASD_STATE_NEW);
618 /* Now wait for the devices to come up. */
619 wait_event(dasd_init_waitq, _wait_for_device(device));
620
621 dasd_reload_device(device);
622 if (device->discipline->kick_validate)
623 device->discipline->kick_validate(device);
624 }
625 EXPORT_SYMBOL(dasd_enable_device);
626
627 /*
628 * SECTION: device operation (interrupt handler, start i/o, term i/o ...)
629 */
630
631 unsigned int dasd_global_profile_level = DASD_PROFILE_OFF;
632
633 #ifdef CONFIG_DASD_PROFILE
634 struct dasd_profile dasd_global_profile = {
635 .lock = __SPIN_LOCK_UNLOCKED(dasd_global_profile.lock),
636 };
637 static struct dentry *dasd_debugfs_global_entry;
638
639 /*
640 * Add profiling information for cqr before execution.
641 */
dasd_profile_start(struct dasd_block * block,struct dasd_ccw_req * cqr,struct request * req)642 static void dasd_profile_start(struct dasd_block *block,
643 struct dasd_ccw_req *cqr,
644 struct request *req)
645 {
646 struct list_head *l;
647 unsigned int counter;
648 struct dasd_device *device;
649
650 /* count the length of the chanq for statistics */
651 counter = 0;
652 if (dasd_global_profile_level || block->profile.data)
653 list_for_each(l, &block->ccw_queue)
654 if (++counter >= 31)
655 break;
656
657 spin_lock(&dasd_global_profile.lock);
658 if (dasd_global_profile.data) {
659 dasd_global_profile.data->dasd_io_nr_req[counter]++;
660 if (rq_data_dir(req) == READ)
661 dasd_global_profile.data->dasd_read_nr_req[counter]++;
662 }
663 spin_unlock(&dasd_global_profile.lock);
664
665 spin_lock(&block->profile.lock);
666 if (block->profile.data) {
667 block->profile.data->dasd_io_nr_req[counter]++;
668 if (rq_data_dir(req) == READ)
669 block->profile.data->dasd_read_nr_req[counter]++;
670 }
671 spin_unlock(&block->profile.lock);
672
673 /*
674 * We count the request for the start device, even though it may run on
675 * some other device due to error recovery. This way we make sure that
676 * we count each request only once.
677 */
678 device = cqr->startdev;
679 if (!device->profile.data)
680 return;
681
682 spin_lock(get_ccwdev_lock(device->cdev));
683 counter = 1; /* request is not yet queued on the start device */
684 list_for_each(l, &device->ccw_queue)
685 if (++counter >= 31)
686 break;
687 spin_unlock(get_ccwdev_lock(device->cdev));
688
689 spin_lock(&device->profile.lock);
690 device->profile.data->dasd_io_nr_req[counter]++;
691 if (rq_data_dir(req) == READ)
692 device->profile.data->dasd_read_nr_req[counter]++;
693 spin_unlock(&device->profile.lock);
694 }
695
696 /*
697 * Add profiling information for cqr after execution.
698 */
699
700 #define dasd_profile_counter(value, index) \
701 { \
702 for (index = 0; index < 31 && value >> (2+index); index++) \
703 ; \
704 }
705
dasd_profile_end_add_data(struct dasd_profile_info * data,int is_alias,int is_tpm,int is_read,long sectors,int sectors_ind,int tottime_ind,int tottimeps_ind,int strtime_ind,int irqtime_ind,int irqtimeps_ind,int endtime_ind)706 static void dasd_profile_end_add_data(struct dasd_profile_info *data,
707 int is_alias,
708 int is_tpm,
709 int is_read,
710 long sectors,
711 int sectors_ind,
712 int tottime_ind,
713 int tottimeps_ind,
714 int strtime_ind,
715 int irqtime_ind,
716 int irqtimeps_ind,
717 int endtime_ind)
718 {
719 /* in case of an overflow, reset the whole profile */
720 if (data->dasd_io_reqs == UINT_MAX) {
721 memset(data, 0, sizeof(*data));
722 ktime_get_real_ts64(&data->starttod);
723 }
724 data->dasd_io_reqs++;
725 data->dasd_io_sects += sectors;
726 if (is_alias)
727 data->dasd_io_alias++;
728 if (is_tpm)
729 data->dasd_io_tpm++;
730
731 data->dasd_io_secs[sectors_ind]++;
732 data->dasd_io_times[tottime_ind]++;
733 data->dasd_io_timps[tottimeps_ind]++;
734 data->dasd_io_time1[strtime_ind]++;
735 data->dasd_io_time2[irqtime_ind]++;
736 data->dasd_io_time2ps[irqtimeps_ind]++;
737 data->dasd_io_time3[endtime_ind]++;
738
739 if (is_read) {
740 data->dasd_read_reqs++;
741 data->dasd_read_sects += sectors;
742 if (is_alias)
743 data->dasd_read_alias++;
744 if (is_tpm)
745 data->dasd_read_tpm++;
746 data->dasd_read_secs[sectors_ind]++;
747 data->dasd_read_times[tottime_ind]++;
748 data->dasd_read_time1[strtime_ind]++;
749 data->dasd_read_time2[irqtime_ind]++;
750 data->dasd_read_time3[endtime_ind]++;
751 }
752 }
753
dasd_profile_end(struct dasd_block * block,struct dasd_ccw_req * cqr,struct request * req)754 static void dasd_profile_end(struct dasd_block *block,
755 struct dasd_ccw_req *cqr,
756 struct request *req)
757 {
758 unsigned long strtime, irqtime, endtime, tottime;
759 unsigned long tottimeps, sectors;
760 struct dasd_device *device;
761 int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind;
762 int irqtime_ind, irqtimeps_ind, endtime_ind;
763 struct dasd_profile_info *data;
764
765 device = cqr->startdev;
766 if (!(dasd_global_profile_level ||
767 block->profile.data ||
768 device->profile.data))
769 return;
770
771 sectors = blk_rq_sectors(req);
772 if (!cqr->buildclk || !cqr->startclk ||
773 !cqr->stopclk || !cqr->endclk ||
774 !sectors)
775 return;
776
777 strtime = ((cqr->startclk - cqr->buildclk) >> 12);
778 irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
779 endtime = ((cqr->endclk - cqr->stopclk) >> 12);
780 tottime = ((cqr->endclk - cqr->buildclk) >> 12);
781 tottimeps = tottime / sectors;
782
783 dasd_profile_counter(sectors, sectors_ind);
784 dasd_profile_counter(tottime, tottime_ind);
785 dasd_profile_counter(tottimeps, tottimeps_ind);
786 dasd_profile_counter(strtime, strtime_ind);
787 dasd_profile_counter(irqtime, irqtime_ind);
788 dasd_profile_counter(irqtime / sectors, irqtimeps_ind);
789 dasd_profile_counter(endtime, endtime_ind);
790
791 spin_lock(&dasd_global_profile.lock);
792 if (dasd_global_profile.data) {
793 data = dasd_global_profile.data;
794 data->dasd_sum_times += tottime;
795 data->dasd_sum_time_str += strtime;
796 data->dasd_sum_time_irq += irqtime;
797 data->dasd_sum_time_end += endtime;
798 dasd_profile_end_add_data(dasd_global_profile.data,
799 cqr->startdev != block->base,
800 cqr->cpmode == 1,
801 rq_data_dir(req) == READ,
802 sectors, sectors_ind, tottime_ind,
803 tottimeps_ind, strtime_ind,
804 irqtime_ind, irqtimeps_ind,
805 endtime_ind);
806 }
807 spin_unlock(&dasd_global_profile.lock);
808
809 spin_lock(&block->profile.lock);
810 if (block->profile.data) {
811 data = block->profile.data;
812 data->dasd_sum_times += tottime;
813 data->dasd_sum_time_str += strtime;
814 data->dasd_sum_time_irq += irqtime;
815 data->dasd_sum_time_end += endtime;
816 dasd_profile_end_add_data(block->profile.data,
817 cqr->startdev != block->base,
818 cqr->cpmode == 1,
819 rq_data_dir(req) == READ,
820 sectors, sectors_ind, tottime_ind,
821 tottimeps_ind, strtime_ind,
822 irqtime_ind, irqtimeps_ind,
823 endtime_ind);
824 }
825 spin_unlock(&block->profile.lock);
826
827 spin_lock(&device->profile.lock);
828 if (device->profile.data) {
829 data = device->profile.data;
830 data->dasd_sum_times += tottime;
831 data->dasd_sum_time_str += strtime;
832 data->dasd_sum_time_irq += irqtime;
833 data->dasd_sum_time_end += endtime;
834 dasd_profile_end_add_data(device->profile.data,
835 cqr->startdev != block->base,
836 cqr->cpmode == 1,
837 rq_data_dir(req) == READ,
838 sectors, sectors_ind, tottime_ind,
839 tottimeps_ind, strtime_ind,
840 irqtime_ind, irqtimeps_ind,
841 endtime_ind);
842 }
843 spin_unlock(&device->profile.lock);
844 }
845
dasd_profile_reset(struct dasd_profile * profile)846 void dasd_profile_reset(struct dasd_profile *profile)
847 {
848 struct dasd_profile_info *data;
849
850 spin_lock_bh(&profile->lock);
851 data = profile->data;
852 if (!data) {
853 spin_unlock_bh(&profile->lock);
854 return;
855 }
856 memset(data, 0, sizeof(*data));
857 ktime_get_real_ts64(&data->starttod);
858 spin_unlock_bh(&profile->lock);
859 }
860
dasd_profile_on(struct dasd_profile * profile)861 int dasd_profile_on(struct dasd_profile *profile)
862 {
863 struct dasd_profile_info *data;
864
865 data = kzalloc(sizeof(*data), GFP_KERNEL);
866 if (!data)
867 return -ENOMEM;
868 spin_lock_bh(&profile->lock);
869 if (profile->data) {
870 spin_unlock_bh(&profile->lock);
871 kfree(data);
872 return 0;
873 }
874 ktime_get_real_ts64(&data->starttod);
875 profile->data = data;
876 spin_unlock_bh(&profile->lock);
877 return 0;
878 }
879
dasd_profile_off(struct dasd_profile * profile)880 void dasd_profile_off(struct dasd_profile *profile)
881 {
882 spin_lock_bh(&profile->lock);
883 kfree(profile->data);
884 profile->data = NULL;
885 spin_unlock_bh(&profile->lock);
886 }
887
dasd_get_user_string(const char __user * user_buf,size_t user_len)888 char *dasd_get_user_string(const char __user *user_buf, size_t user_len)
889 {
890 char *buffer;
891
892 buffer = vmalloc(user_len + 1);
893 if (buffer == NULL)
894 return ERR_PTR(-ENOMEM);
895 if (copy_from_user(buffer, user_buf, user_len) != 0) {
896 vfree(buffer);
897 return ERR_PTR(-EFAULT);
898 }
899 /* got the string, now strip linefeed. */
900 if (buffer[user_len - 1] == '\n')
901 buffer[user_len - 1] = 0;
902 else
903 buffer[user_len] = 0;
904 return buffer;
905 }
906
dasd_stats_write(struct file * file,const char __user * user_buf,size_t user_len,loff_t * pos)907 static ssize_t dasd_stats_write(struct file *file,
908 const char __user *user_buf,
909 size_t user_len, loff_t *pos)
910 {
911 char *buffer, *str;
912 int rc;
913 struct seq_file *m = (struct seq_file *)file->private_data;
914 struct dasd_profile *prof = m->private;
915
916 if (user_len > 65536)
917 user_len = 65536;
918 buffer = dasd_get_user_string(user_buf, user_len);
919 if (IS_ERR(buffer))
920 return PTR_ERR(buffer);
921
922 str = skip_spaces(buffer);
923 rc = user_len;
924 if (strncmp(str, "reset", 5) == 0) {
925 dasd_profile_reset(prof);
926 } else if (strncmp(str, "on", 2) == 0) {
927 rc = dasd_profile_on(prof);
928 if (rc)
929 goto out;
930 rc = user_len;
931 if (prof == &dasd_global_profile) {
932 dasd_profile_reset(prof);
933 dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY;
934 }
935 } else if (strncmp(str, "off", 3) == 0) {
936 if (prof == &dasd_global_profile)
937 dasd_global_profile_level = DASD_PROFILE_OFF;
938 dasd_profile_off(prof);
939 } else
940 rc = -EINVAL;
941 out:
942 vfree(buffer);
943 return rc;
944 }
945
dasd_stats_array(struct seq_file * m,unsigned int * array)946 static void dasd_stats_array(struct seq_file *m, unsigned int *array)
947 {
948 int i;
949
950 for (i = 0; i < 32; i++)
951 seq_printf(m, "%u ", array[i]);
952 seq_putc(m, '\n');
953 }
954
dasd_stats_seq_print(struct seq_file * m,struct dasd_profile_info * data)955 static void dasd_stats_seq_print(struct seq_file *m,
956 struct dasd_profile_info *data)
957 {
958 seq_printf(m, "start_time %lld.%09ld\n",
959 (s64)data->starttod.tv_sec, data->starttod.tv_nsec);
960 seq_printf(m, "total_requests %u\n", data->dasd_io_reqs);
961 seq_printf(m, "total_sectors %u\n", data->dasd_io_sects);
962 seq_printf(m, "total_pav %u\n", data->dasd_io_alias);
963 seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm);
964 seq_printf(m, "avg_total %lu\n", data->dasd_io_reqs ?
965 data->dasd_sum_times / data->dasd_io_reqs : 0UL);
966 seq_printf(m, "avg_build_to_ssch %lu\n", data->dasd_io_reqs ?
967 data->dasd_sum_time_str / data->dasd_io_reqs : 0UL);
968 seq_printf(m, "avg_ssch_to_irq %lu\n", data->dasd_io_reqs ?
969 data->dasd_sum_time_irq / data->dasd_io_reqs : 0UL);
970 seq_printf(m, "avg_irq_to_end %lu\n", data->dasd_io_reqs ?
971 data->dasd_sum_time_end / data->dasd_io_reqs : 0UL);
972 seq_puts(m, "histogram_sectors ");
973 dasd_stats_array(m, data->dasd_io_secs);
974 seq_puts(m, "histogram_io_times ");
975 dasd_stats_array(m, data->dasd_io_times);
976 seq_puts(m, "histogram_io_times_weighted ");
977 dasd_stats_array(m, data->dasd_io_timps);
978 seq_puts(m, "histogram_time_build_to_ssch ");
979 dasd_stats_array(m, data->dasd_io_time1);
980 seq_puts(m, "histogram_time_ssch_to_irq ");
981 dasd_stats_array(m, data->dasd_io_time2);
982 seq_puts(m, "histogram_time_ssch_to_irq_weighted ");
983 dasd_stats_array(m, data->dasd_io_time2ps);
984 seq_puts(m, "histogram_time_irq_to_end ");
985 dasd_stats_array(m, data->dasd_io_time3);
986 seq_puts(m, "histogram_ccw_queue_length ");
987 dasd_stats_array(m, data->dasd_io_nr_req);
988 seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs);
989 seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects);
990 seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias);
991 seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm);
992 seq_puts(m, "histogram_read_sectors ");
993 dasd_stats_array(m, data->dasd_read_secs);
994 seq_puts(m, "histogram_read_times ");
995 dasd_stats_array(m, data->dasd_read_times);
996 seq_puts(m, "histogram_read_time_build_to_ssch ");
997 dasd_stats_array(m, data->dasd_read_time1);
998 seq_puts(m, "histogram_read_time_ssch_to_irq ");
999 dasd_stats_array(m, data->dasd_read_time2);
1000 seq_puts(m, "histogram_read_time_irq_to_end ");
1001 dasd_stats_array(m, data->dasd_read_time3);
1002 seq_puts(m, "histogram_read_ccw_queue_length ");
1003 dasd_stats_array(m, data->dasd_read_nr_req);
1004 }
1005
dasd_stats_show(struct seq_file * m,void * v)1006 static int dasd_stats_show(struct seq_file *m, void *v)
1007 {
1008 struct dasd_profile *profile;
1009 struct dasd_profile_info *data;
1010
1011 profile = m->private;
1012 spin_lock_bh(&profile->lock);
1013 data = profile->data;
1014 if (!data) {
1015 spin_unlock_bh(&profile->lock);
1016 seq_puts(m, "disabled\n");
1017 return 0;
1018 }
1019 dasd_stats_seq_print(m, data);
1020 spin_unlock_bh(&profile->lock);
1021 return 0;
1022 }
1023
dasd_stats_open(struct inode * inode,struct file * file)1024 static int dasd_stats_open(struct inode *inode, struct file *file)
1025 {
1026 struct dasd_profile *profile = inode->i_private;
1027 return single_open(file, dasd_stats_show, profile);
1028 }
1029
1030 static const struct file_operations dasd_stats_raw_fops = {
1031 .owner = THIS_MODULE,
1032 .open = dasd_stats_open,
1033 .read = seq_read,
1034 .llseek = seq_lseek,
1035 .release = single_release,
1036 .write = dasd_stats_write,
1037 };
1038
dasd_profile_init(struct dasd_profile * profile,struct dentry * base_dentry)1039 static void dasd_profile_init(struct dasd_profile *profile,
1040 struct dentry *base_dentry)
1041 {
1042 umode_t mode;
1043 struct dentry *pde;
1044
1045 if (!base_dentry)
1046 return;
1047 profile->dentry = NULL;
1048 profile->data = NULL;
1049 mode = (S_IRUSR | S_IWUSR | S_IFREG);
1050 pde = debugfs_create_file("statistics", mode, base_dentry,
1051 profile, &dasd_stats_raw_fops);
1052 if (pde && !IS_ERR(pde))
1053 profile->dentry = pde;
1054 return;
1055 }
1056
dasd_profile_exit(struct dasd_profile * profile)1057 static void dasd_profile_exit(struct dasd_profile *profile)
1058 {
1059 dasd_profile_off(profile);
1060 debugfs_remove(profile->dentry);
1061 profile->dentry = NULL;
1062 }
1063
dasd_statistics_removeroot(void)1064 static void dasd_statistics_removeroot(void)
1065 {
1066 dasd_global_profile_level = DASD_PROFILE_OFF;
1067 dasd_profile_exit(&dasd_global_profile);
1068 debugfs_remove(dasd_debugfs_global_entry);
1069 debugfs_remove(dasd_debugfs_root_entry);
1070 }
1071
dasd_statistics_createroot(void)1072 static void dasd_statistics_createroot(void)
1073 {
1074 struct dentry *pde;
1075
1076 dasd_debugfs_root_entry = NULL;
1077 pde = debugfs_create_dir("dasd", NULL);
1078 if (!pde || IS_ERR(pde))
1079 goto error;
1080 dasd_debugfs_root_entry = pde;
1081 pde = debugfs_create_dir("global", dasd_debugfs_root_entry);
1082 if (!pde || IS_ERR(pde))
1083 goto error;
1084 dasd_debugfs_global_entry = pde;
1085 dasd_profile_init(&dasd_global_profile, dasd_debugfs_global_entry);
1086 return;
1087
1088 error:
1089 DBF_EVENT(DBF_ERR, "%s",
1090 "Creation of the dasd debugfs interface failed");
1091 dasd_statistics_removeroot();
1092 return;
1093 }
1094
1095 #else
1096 #define dasd_profile_start(block, cqr, req) do {} while (0)
1097 #define dasd_profile_end(block, cqr, req) do {} while (0)
1098
dasd_statistics_createroot(void)1099 static void dasd_statistics_createroot(void)
1100 {
1101 return;
1102 }
1103
dasd_statistics_removeroot(void)1104 static void dasd_statistics_removeroot(void)
1105 {
1106 return;
1107 }
1108
dasd_profile_init(struct dasd_profile * profile,struct dentry * base_dentry)1109 static void dasd_profile_init(struct dasd_profile *profile,
1110 struct dentry *base_dentry)
1111 {
1112 return;
1113 }
1114
dasd_profile_exit(struct dasd_profile * profile)1115 static void dasd_profile_exit(struct dasd_profile *profile)
1116 {
1117 return;
1118 }
1119
dasd_profile_on(struct dasd_profile * profile)1120 int dasd_profile_on(struct dasd_profile *profile)
1121 {
1122 return 0;
1123 }
1124
1125 #endif /* CONFIG_DASD_PROFILE */
1126
dasd_hosts_show(struct seq_file * m,void * v)1127 static int dasd_hosts_show(struct seq_file *m, void *v)
1128 {
1129 struct dasd_device *device;
1130 int rc = -EOPNOTSUPP;
1131
1132 device = m->private;
1133 dasd_get_device(device);
1134
1135 if (device->discipline->hosts_print)
1136 rc = device->discipline->hosts_print(device, m);
1137
1138 dasd_put_device(device);
1139 return rc;
1140 }
1141
1142 DEFINE_SHOW_ATTRIBUTE(dasd_hosts);
1143
dasd_hosts_exit(struct dasd_device * device)1144 static void dasd_hosts_exit(struct dasd_device *device)
1145 {
1146 debugfs_remove(device->hosts_dentry);
1147 device->hosts_dentry = NULL;
1148 }
1149
dasd_hosts_init(struct dentry * base_dentry,struct dasd_device * device)1150 static void dasd_hosts_init(struct dentry *base_dentry,
1151 struct dasd_device *device)
1152 {
1153 struct dentry *pde;
1154 umode_t mode;
1155
1156 if (!base_dentry)
1157 return;
1158
1159 mode = S_IRUSR | S_IFREG;
1160 pde = debugfs_create_file("host_access_list", mode, base_dentry,
1161 device, &dasd_hosts_fops);
1162 if (pde && !IS_ERR(pde))
1163 device->hosts_dentry = pde;
1164 }
1165
dasd_smalloc_request(int magic,int cplength,int datasize,struct dasd_device * device,struct dasd_ccw_req * cqr)1166 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength, int datasize,
1167 struct dasd_device *device,
1168 struct dasd_ccw_req *cqr)
1169 {
1170 unsigned long flags;
1171 char *data, *chunk;
1172 int size = 0;
1173
1174 if (cplength > 0)
1175 size += cplength * sizeof(struct ccw1);
1176 if (datasize > 0)
1177 size += datasize;
1178 if (!cqr)
1179 size += (sizeof(*cqr) + 7L) & -8L;
1180
1181 spin_lock_irqsave(&device->mem_lock, flags);
1182 data = chunk = dasd_alloc_chunk(&device->ccw_chunks, size);
1183 spin_unlock_irqrestore(&device->mem_lock, flags);
1184 if (!chunk)
1185 return ERR_PTR(-ENOMEM);
1186 if (!cqr) {
1187 cqr = (void *) data;
1188 data += (sizeof(*cqr) + 7L) & -8L;
1189 }
1190 memset(cqr, 0, sizeof(*cqr));
1191 cqr->mem_chunk = chunk;
1192 if (cplength > 0) {
1193 cqr->cpaddr = data;
1194 data += cplength * sizeof(struct ccw1);
1195 memset(cqr->cpaddr, 0, cplength * sizeof(struct ccw1));
1196 }
1197 if (datasize > 0) {
1198 cqr->data = data;
1199 memset(cqr->data, 0, datasize);
1200 }
1201 cqr->magic = magic;
1202 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1203 dasd_get_device(device);
1204 return cqr;
1205 }
1206 EXPORT_SYMBOL(dasd_smalloc_request);
1207
dasd_fmalloc_request(int magic,int cplength,int datasize,struct dasd_device * device)1208 struct dasd_ccw_req *dasd_fmalloc_request(int magic, int cplength,
1209 int datasize,
1210 struct dasd_device *device)
1211 {
1212 struct dasd_ccw_req *cqr;
1213 unsigned long flags;
1214 int size, cqr_size;
1215 char *data;
1216
1217 cqr_size = (sizeof(*cqr) + 7L) & -8L;
1218 size = cqr_size;
1219 if (cplength > 0)
1220 size += cplength * sizeof(struct ccw1);
1221 if (datasize > 0)
1222 size += datasize;
1223
1224 spin_lock_irqsave(&device->mem_lock, flags);
1225 cqr = dasd_alloc_chunk(&device->ese_chunks, size);
1226 spin_unlock_irqrestore(&device->mem_lock, flags);
1227 if (!cqr)
1228 return ERR_PTR(-ENOMEM);
1229 memset(cqr, 0, sizeof(*cqr));
1230 data = (char *)cqr + cqr_size;
1231 cqr->cpaddr = NULL;
1232 if (cplength > 0) {
1233 cqr->cpaddr = data;
1234 data += cplength * sizeof(struct ccw1);
1235 memset(cqr->cpaddr, 0, cplength * sizeof(struct ccw1));
1236 }
1237 cqr->data = NULL;
1238 if (datasize > 0) {
1239 cqr->data = data;
1240 memset(cqr->data, 0, datasize);
1241 }
1242
1243 cqr->magic = magic;
1244 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1245 dasd_get_device(device);
1246
1247 return cqr;
1248 }
1249 EXPORT_SYMBOL(dasd_fmalloc_request);
1250
dasd_sfree_request(struct dasd_ccw_req * cqr,struct dasd_device * device)1251 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1252 {
1253 unsigned long flags;
1254
1255 spin_lock_irqsave(&device->mem_lock, flags);
1256 dasd_free_chunk(&device->ccw_chunks, cqr->mem_chunk);
1257 spin_unlock_irqrestore(&device->mem_lock, flags);
1258 dasd_put_device(device);
1259 }
1260 EXPORT_SYMBOL(dasd_sfree_request);
1261
dasd_ffree_request(struct dasd_ccw_req * cqr,struct dasd_device * device)1262 void dasd_ffree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1263 {
1264 unsigned long flags;
1265
1266 spin_lock_irqsave(&device->mem_lock, flags);
1267 dasd_free_chunk(&device->ese_chunks, cqr);
1268 spin_unlock_irqrestore(&device->mem_lock, flags);
1269 dasd_put_device(device);
1270 }
1271 EXPORT_SYMBOL(dasd_ffree_request);
1272
1273 /*
1274 * Check discipline magic in cqr.
1275 */
dasd_check_cqr(struct dasd_ccw_req * cqr)1276 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
1277 {
1278 struct dasd_device *device;
1279
1280 if (cqr == NULL)
1281 return -EINVAL;
1282 device = cqr->startdev;
1283 if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
1284 DBF_DEV_EVENT(DBF_WARNING, device,
1285 " dasd_ccw_req 0x%08x magic doesn't match"
1286 " discipline 0x%08x",
1287 cqr->magic,
1288 *(unsigned int *) device->discipline->name);
1289 return -EINVAL;
1290 }
1291 return 0;
1292 }
1293
1294 /*
1295 * Terminate the current i/o and set the request to clear_pending.
1296 * Timer keeps device runnig.
1297 * ccw_device_clear can fail if the i/o subsystem
1298 * is in a bad mood.
1299 */
dasd_term_IO(struct dasd_ccw_req * cqr)1300 int dasd_term_IO(struct dasd_ccw_req *cqr)
1301 {
1302 struct dasd_device *device;
1303 int retries, rc;
1304 char errorstring[ERRORLENGTH];
1305
1306 /* Check the cqr */
1307 rc = dasd_check_cqr(cqr);
1308 if (rc)
1309 return rc;
1310 retries = 0;
1311 device = (struct dasd_device *) cqr->startdev;
1312 while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
1313 rc = ccw_device_clear(device->cdev, (long) cqr);
1314 switch (rc) {
1315 case 0: /* termination successful */
1316 cqr->status = DASD_CQR_CLEAR_PENDING;
1317 cqr->stopclk = get_tod_clock();
1318 cqr->starttime = 0;
1319 DBF_DEV_EVENT(DBF_DEBUG, device,
1320 "terminate cqr %p successful",
1321 cqr);
1322 break;
1323 case -ENODEV:
1324 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1325 "device gone, retry");
1326 break;
1327 case -EINVAL:
1328 /*
1329 * device not valid so no I/O could be running
1330 * handle CQR as termination successful
1331 */
1332 cqr->status = DASD_CQR_CLEARED;
1333 cqr->stopclk = get_tod_clock();
1334 cqr->starttime = 0;
1335 /* no retries for invalid devices */
1336 cqr->retries = -1;
1337 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1338 "EINVAL, handle as terminated");
1339 /* fake rc to success */
1340 rc = 0;
1341 break;
1342 default:
1343 /* internal error 10 - unknown rc*/
1344 snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
1345 dev_err(&device->cdev->dev, "An error occurred in the "
1346 "DASD device driver, reason=%s\n", errorstring);
1347 BUG();
1348 break;
1349 }
1350 retries++;
1351 }
1352 dasd_schedule_device_bh(device);
1353 return rc;
1354 }
1355 EXPORT_SYMBOL(dasd_term_IO);
1356
1357 /*
1358 * Start the i/o. This start_IO can fail if the channel is really busy.
1359 * In that case set up a timer to start the request later.
1360 */
dasd_start_IO(struct dasd_ccw_req * cqr)1361 int dasd_start_IO(struct dasd_ccw_req *cqr)
1362 {
1363 struct dasd_device *device;
1364 int rc;
1365 char errorstring[ERRORLENGTH];
1366
1367 /* Check the cqr */
1368 rc = dasd_check_cqr(cqr);
1369 if (rc) {
1370 cqr->intrc = rc;
1371 return rc;
1372 }
1373 device = (struct dasd_device *) cqr->startdev;
1374 if (((cqr->block &&
1375 test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) ||
1376 test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) &&
1377 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
1378 DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p "
1379 "because of stolen lock", cqr);
1380 cqr->status = DASD_CQR_ERROR;
1381 cqr->intrc = -EPERM;
1382 return -EPERM;
1383 }
1384 if (cqr->retries < 0) {
1385 /* internal error 14 - start_IO run out of retries */
1386 sprintf(errorstring, "14 %p", cqr);
1387 dev_err(&device->cdev->dev, "An error occurred in the DASD "
1388 "device driver, reason=%s\n", errorstring);
1389 cqr->status = DASD_CQR_ERROR;
1390 return -EIO;
1391 }
1392 cqr->startclk = get_tod_clock();
1393 cqr->starttime = jiffies;
1394 cqr->retries--;
1395 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1396 cqr->lpm &= dasd_path_get_opm(device);
1397 if (!cqr->lpm)
1398 cqr->lpm = dasd_path_get_opm(device);
1399 }
1400 /*
1401 * remember the amount of formatted tracks to prevent double format on
1402 * ESE devices
1403 */
1404 if (cqr->block)
1405 cqr->trkcount = atomic_read(&cqr->block->trkcount);
1406
1407 if (cqr->cpmode == 1) {
1408 rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
1409 (long) cqr, cqr->lpm);
1410 } else {
1411 rc = ccw_device_start(device->cdev, cqr->cpaddr,
1412 (long) cqr, cqr->lpm, 0);
1413 }
1414 switch (rc) {
1415 case 0:
1416 cqr->status = DASD_CQR_IN_IO;
1417 break;
1418 case -EBUSY:
1419 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1420 "start_IO: device busy, retry later");
1421 break;
1422 case -EACCES:
1423 /* -EACCES indicates that the request used only a subset of the
1424 * available paths and all these paths are gone. If the lpm of
1425 * this request was only a subset of the opm (e.g. the ppm) then
1426 * we just do a retry with all available paths.
1427 * If we already use the full opm, something is amiss, and we
1428 * need a full path verification.
1429 */
1430 if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1431 DBF_DEV_EVENT(DBF_WARNING, device,
1432 "start_IO: selected paths gone (%x)",
1433 cqr->lpm);
1434 } else if (cqr->lpm != dasd_path_get_opm(device)) {
1435 cqr->lpm = dasd_path_get_opm(device);
1436 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
1437 "start_IO: selected paths gone,"
1438 " retry on all paths");
1439 } else {
1440 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1441 "start_IO: all paths in opm gone,"
1442 " do path verification");
1443 dasd_generic_last_path_gone(device);
1444 dasd_path_no_path(device);
1445 dasd_path_set_tbvpm(device,
1446 ccw_device_get_path_mask(
1447 device->cdev));
1448 }
1449 break;
1450 case -ENODEV:
1451 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1452 "start_IO: -ENODEV device gone, retry");
1453 /* this is equivalent to CC=3 for SSCH report this to EER */
1454 dasd_handle_autoquiesce(device, cqr, DASD_EER_STARTIO);
1455 break;
1456 case -EIO:
1457 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1458 "start_IO: -EIO device gone, retry");
1459 break;
1460 case -EINVAL:
1461 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1462 "start_IO: -EINVAL device currently "
1463 "not accessible");
1464 break;
1465 default:
1466 /* internal error 11 - unknown rc */
1467 snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
1468 dev_err(&device->cdev->dev,
1469 "An error occurred in the DASD device driver, "
1470 "reason=%s\n", errorstring);
1471 BUG();
1472 break;
1473 }
1474 cqr->intrc = rc;
1475 return rc;
1476 }
1477 EXPORT_SYMBOL(dasd_start_IO);
1478
1479 /*
1480 * Timeout function for dasd devices. This is used for different purposes
1481 * 1) missing interrupt handler for normal operation
1482 * 2) delayed start of request where start_IO failed with -EBUSY
1483 * 3) timeout for missing state change interrupts
1484 * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
1485 * DASD_CQR_QUEUED for 2) and 3).
1486 */
dasd_device_timeout(struct timer_list * t)1487 static void dasd_device_timeout(struct timer_list *t)
1488 {
1489 unsigned long flags;
1490 struct dasd_device *device;
1491
1492 device = from_timer(device, t, timer);
1493 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1494 /* re-activate request queue */
1495 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1496 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1497 dasd_schedule_device_bh(device);
1498 }
1499
1500 /*
1501 * Setup timeout for a device in jiffies.
1502 */
dasd_device_set_timer(struct dasd_device * device,int expires)1503 void dasd_device_set_timer(struct dasd_device *device, int expires)
1504 {
1505 if (expires == 0)
1506 del_timer(&device->timer);
1507 else
1508 mod_timer(&device->timer, jiffies + expires);
1509 }
1510 EXPORT_SYMBOL(dasd_device_set_timer);
1511
1512 /*
1513 * Clear timeout for a device.
1514 */
dasd_device_clear_timer(struct dasd_device * device)1515 void dasd_device_clear_timer(struct dasd_device *device)
1516 {
1517 del_timer(&device->timer);
1518 }
1519 EXPORT_SYMBOL(dasd_device_clear_timer);
1520
dasd_handle_killed_request(struct ccw_device * cdev,unsigned long intparm)1521 static void dasd_handle_killed_request(struct ccw_device *cdev,
1522 unsigned long intparm)
1523 {
1524 struct dasd_ccw_req *cqr;
1525 struct dasd_device *device;
1526
1527 if (!intparm)
1528 return;
1529 cqr = (struct dasd_ccw_req *) intparm;
1530 if (cqr->status != DASD_CQR_IN_IO) {
1531 DBF_EVENT_DEVID(DBF_DEBUG, cdev,
1532 "invalid status in handle_killed_request: "
1533 "%02x", cqr->status);
1534 return;
1535 }
1536
1537 device = dasd_device_from_cdev_locked(cdev);
1538 if (IS_ERR(device)) {
1539 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1540 "unable to get device from cdev");
1541 return;
1542 }
1543
1544 if (!cqr->startdev ||
1545 device != cqr->startdev ||
1546 strncmp(cqr->startdev->discipline->ebcname,
1547 (char *) &cqr->magic, 4)) {
1548 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1549 "invalid device in request");
1550 dasd_put_device(device);
1551 return;
1552 }
1553
1554 /* Schedule request to be retried. */
1555 cqr->status = DASD_CQR_QUEUED;
1556
1557 dasd_device_clear_timer(device);
1558 dasd_schedule_device_bh(device);
1559 dasd_put_device(device);
1560 }
1561
dasd_generic_handle_state_change(struct dasd_device * device)1562 void dasd_generic_handle_state_change(struct dasd_device *device)
1563 {
1564 /* First of all start sense subsystem status request. */
1565 dasd_eer_snss(device);
1566
1567 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1568 dasd_schedule_device_bh(device);
1569 if (device->block) {
1570 dasd_schedule_block_bh(device->block);
1571 if (device->block->gdp)
1572 blk_mq_run_hw_queues(device->block->gdp->queue, true);
1573 }
1574 }
1575 EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
1576
dasd_check_hpf_error(struct irb * irb)1577 static int dasd_check_hpf_error(struct irb *irb)
1578 {
1579 return (scsw_tm_is_valid_schxs(&irb->scsw) &&
1580 (irb->scsw.tm.sesq == SCSW_SESQ_DEV_NOFCX ||
1581 irb->scsw.tm.sesq == SCSW_SESQ_PATH_NOFCX));
1582 }
1583
dasd_ese_needs_format(struct dasd_block * block,struct irb * irb)1584 static int dasd_ese_needs_format(struct dasd_block *block, struct irb *irb)
1585 {
1586 struct dasd_device *device = NULL;
1587 u8 *sense = NULL;
1588
1589 if (!block)
1590 return 0;
1591 device = block->base;
1592 if (!device || !device->discipline->is_ese)
1593 return 0;
1594 if (!device->discipline->is_ese(device))
1595 return 0;
1596
1597 sense = dasd_get_sense(irb);
1598 if (!sense)
1599 return 0;
1600
1601 return !!(sense[1] & SNS1_NO_REC_FOUND) ||
1602 !!(sense[1] & SNS1_FILE_PROTECTED) ||
1603 scsw_cstat(&irb->scsw) == SCHN_STAT_INCORR_LEN;
1604 }
1605
dasd_ese_oos_cond(u8 * sense)1606 static int dasd_ese_oos_cond(u8 *sense)
1607 {
1608 return sense[0] & SNS0_EQUIPMENT_CHECK &&
1609 sense[1] & SNS1_PERM_ERR &&
1610 sense[1] & SNS1_WRITE_INHIBITED &&
1611 sense[25] == 0x01;
1612 }
1613
1614 /*
1615 * Interrupt handler for "normal" ssch-io based dasd devices.
1616 */
dasd_int_handler(struct ccw_device * cdev,unsigned long intparm,struct irb * irb)1617 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
1618 struct irb *irb)
1619 {
1620 struct dasd_ccw_req *cqr, *next, *fcqr;
1621 struct dasd_device *device;
1622 unsigned long now;
1623 int nrf_suppressed = 0;
1624 int fp_suppressed = 0;
1625 struct request *req;
1626 u8 *sense = NULL;
1627 int expires;
1628
1629 cqr = (struct dasd_ccw_req *) intparm;
1630 if (IS_ERR(irb)) {
1631 switch (PTR_ERR(irb)) {
1632 case -EIO:
1633 if (cqr && cqr->status == DASD_CQR_CLEAR_PENDING) {
1634 device = cqr->startdev;
1635 cqr->status = DASD_CQR_CLEARED;
1636 dasd_device_clear_timer(device);
1637 wake_up(&dasd_flush_wq);
1638 dasd_schedule_device_bh(device);
1639 return;
1640 }
1641 break;
1642 case -ETIMEDOUT:
1643 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1644 "request timed out\n", __func__);
1645 break;
1646 default:
1647 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1648 "unknown error %ld\n", __func__,
1649 PTR_ERR(irb));
1650 }
1651 dasd_handle_killed_request(cdev, intparm);
1652 return;
1653 }
1654
1655 now = get_tod_clock();
1656 /* check for conditions that should be handled immediately */
1657 if (!cqr ||
1658 !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1659 scsw_cstat(&irb->scsw) == 0)) {
1660 if (cqr)
1661 memcpy(&cqr->irb, irb, sizeof(*irb));
1662 device = dasd_device_from_cdev_locked(cdev);
1663 if (IS_ERR(device))
1664 return;
1665 /* ignore unsolicited interrupts for DIAG discipline */
1666 if (device->discipline == dasd_diag_discipline_pointer) {
1667 dasd_put_device(device);
1668 return;
1669 }
1670
1671 /*
1672 * In some cases 'File Protected' or 'No Record Found' errors
1673 * might be expected and debug log messages for the
1674 * corresponding interrupts shouldn't be written then.
1675 * Check if either of the according suppress bits is set.
1676 */
1677 sense = dasd_get_sense(irb);
1678 if (sense) {
1679 fp_suppressed = (sense[1] & SNS1_FILE_PROTECTED) &&
1680 test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags);
1681 nrf_suppressed = (sense[1] & SNS1_NO_REC_FOUND) &&
1682 test_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags);
1683
1684 /*
1685 * Extent pool probably out-of-space.
1686 * Stop device and check exhaust level.
1687 */
1688 if (dasd_ese_oos_cond(sense)) {
1689 dasd_generic_space_exhaust(device, cqr);
1690 device->discipline->ext_pool_exhaust(device, cqr);
1691 dasd_put_device(device);
1692 return;
1693 }
1694 }
1695 if (!(fp_suppressed || nrf_suppressed))
1696 device->discipline->dump_sense_dbf(device, irb, "int");
1697
1698 if (device->features & DASD_FEATURE_ERPLOG)
1699 device->discipline->dump_sense(device, cqr, irb);
1700 device->discipline->check_for_device_change(device, cqr, irb);
1701 dasd_put_device(device);
1702 }
1703
1704 /* check for attention message */
1705 if (scsw_dstat(&irb->scsw) & DEV_STAT_ATTENTION) {
1706 device = dasd_device_from_cdev_locked(cdev);
1707 if (!IS_ERR(device)) {
1708 device->discipline->check_attention(device,
1709 irb->esw.esw1.lpum);
1710 dasd_put_device(device);
1711 }
1712 }
1713
1714 if (!cqr)
1715 return;
1716
1717 device = (struct dasd_device *) cqr->startdev;
1718 if (!device ||
1719 strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
1720 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1721 "invalid device in request");
1722 return;
1723 }
1724
1725 if (dasd_ese_needs_format(cqr->block, irb)) {
1726 req = dasd_get_callback_data(cqr);
1727 if (!req) {
1728 cqr->status = DASD_CQR_ERROR;
1729 return;
1730 }
1731 if (rq_data_dir(req) == READ) {
1732 device->discipline->ese_read(cqr, irb);
1733 cqr->status = DASD_CQR_SUCCESS;
1734 cqr->stopclk = now;
1735 dasd_device_clear_timer(device);
1736 dasd_schedule_device_bh(device);
1737 return;
1738 }
1739 fcqr = device->discipline->ese_format(device, cqr, irb);
1740 if (IS_ERR(fcqr)) {
1741 if (PTR_ERR(fcqr) == -EINVAL) {
1742 cqr->status = DASD_CQR_ERROR;
1743 return;
1744 }
1745 /*
1746 * If we can't format now, let the request go
1747 * one extra round. Maybe we can format later.
1748 */
1749 cqr->status = DASD_CQR_QUEUED;
1750 dasd_schedule_device_bh(device);
1751 return;
1752 } else {
1753 fcqr->status = DASD_CQR_QUEUED;
1754 cqr->status = DASD_CQR_QUEUED;
1755 list_add(&fcqr->devlist, &device->ccw_queue);
1756 dasd_schedule_device_bh(device);
1757 return;
1758 }
1759 }
1760
1761 /* Check for clear pending */
1762 if (cqr->status == DASD_CQR_CLEAR_PENDING &&
1763 scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
1764 cqr->status = DASD_CQR_CLEARED;
1765 dasd_device_clear_timer(device);
1766 wake_up(&dasd_flush_wq);
1767 dasd_schedule_device_bh(device);
1768 return;
1769 }
1770
1771 /* check status - the request might have been killed by dyn detach */
1772 if (cqr->status != DASD_CQR_IN_IO) {
1773 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
1774 "status %02x", dev_name(&cdev->dev), cqr->status);
1775 return;
1776 }
1777
1778 next = NULL;
1779 expires = 0;
1780 if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1781 scsw_cstat(&irb->scsw) == 0) {
1782 /* request was completed successfully */
1783 cqr->status = DASD_CQR_SUCCESS;
1784 cqr->stopclk = now;
1785 /* Start first request on queue if possible -> fast_io. */
1786 if (cqr->devlist.next != &device->ccw_queue) {
1787 next = list_entry(cqr->devlist.next,
1788 struct dasd_ccw_req, devlist);
1789 }
1790 } else { /* error */
1791 /* check for HPF error
1792 * call discipline function to requeue all requests
1793 * and disable HPF accordingly
1794 */
1795 if (cqr->cpmode && dasd_check_hpf_error(irb) &&
1796 device->discipline->handle_hpf_error)
1797 device->discipline->handle_hpf_error(device, irb);
1798 /*
1799 * If we don't want complex ERP for this request, then just
1800 * reset this and retry it in the fastpath
1801 */
1802 if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
1803 cqr->retries > 0) {
1804 if (cqr->lpm == dasd_path_get_opm(device))
1805 DBF_DEV_EVENT(DBF_DEBUG, device,
1806 "default ERP in fastpath "
1807 "(%i retries left)",
1808 cqr->retries);
1809 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))
1810 cqr->lpm = dasd_path_get_opm(device);
1811 cqr->status = DASD_CQR_QUEUED;
1812 next = cqr;
1813 } else
1814 cqr->status = DASD_CQR_ERROR;
1815 }
1816 if (next && (next->status == DASD_CQR_QUEUED) &&
1817 (!device->stopped)) {
1818 if (device->discipline->start_IO(next) == 0)
1819 expires = next->expires;
1820 }
1821 if (expires != 0)
1822 dasd_device_set_timer(device, expires);
1823 else
1824 dasd_device_clear_timer(device);
1825 dasd_schedule_device_bh(device);
1826 }
1827 EXPORT_SYMBOL(dasd_int_handler);
1828
dasd_generic_uc_handler(struct ccw_device * cdev,struct irb * irb)1829 enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb)
1830 {
1831 struct dasd_device *device;
1832
1833 device = dasd_device_from_cdev_locked(cdev);
1834
1835 if (IS_ERR(device))
1836 goto out;
1837 if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
1838 device->state != device->target ||
1839 !device->discipline->check_for_device_change){
1840 dasd_put_device(device);
1841 goto out;
1842 }
1843 if (device->discipline->dump_sense_dbf)
1844 device->discipline->dump_sense_dbf(device, irb, "uc");
1845 device->discipline->check_for_device_change(device, NULL, irb);
1846 dasd_put_device(device);
1847 out:
1848 return UC_TODO_RETRY;
1849 }
1850 EXPORT_SYMBOL_GPL(dasd_generic_uc_handler);
1851
1852 /*
1853 * If we have an error on a dasd_block layer request then we cancel
1854 * and return all further requests from the same dasd_block as well.
1855 */
__dasd_device_recovery(struct dasd_device * device,struct dasd_ccw_req * ref_cqr)1856 static void __dasd_device_recovery(struct dasd_device *device,
1857 struct dasd_ccw_req *ref_cqr)
1858 {
1859 struct list_head *l, *n;
1860 struct dasd_ccw_req *cqr;
1861
1862 /*
1863 * only requeue request that came from the dasd_block layer
1864 */
1865 if (!ref_cqr->block)
1866 return;
1867
1868 list_for_each_safe(l, n, &device->ccw_queue) {
1869 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1870 if (cqr->status == DASD_CQR_QUEUED &&
1871 ref_cqr->block == cqr->block) {
1872 cqr->status = DASD_CQR_CLEARED;
1873 }
1874 }
1875 };
1876
1877 /*
1878 * Remove those ccw requests from the queue that need to be returned
1879 * to the upper layer.
1880 */
__dasd_device_process_ccw_queue(struct dasd_device * device,struct list_head * final_queue)1881 static void __dasd_device_process_ccw_queue(struct dasd_device *device,
1882 struct list_head *final_queue)
1883 {
1884 struct list_head *l, *n;
1885 struct dasd_ccw_req *cqr;
1886
1887 /* Process request with final status. */
1888 list_for_each_safe(l, n, &device->ccw_queue) {
1889 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1890
1891 /* Skip any non-final request. */
1892 if (cqr->status == DASD_CQR_QUEUED ||
1893 cqr->status == DASD_CQR_IN_IO ||
1894 cqr->status == DASD_CQR_CLEAR_PENDING)
1895 continue;
1896 if (cqr->status == DASD_CQR_ERROR) {
1897 __dasd_device_recovery(device, cqr);
1898 }
1899 /* Rechain finished requests to final queue */
1900 list_move_tail(&cqr->devlist, final_queue);
1901 }
1902 }
1903
__dasd_process_cqr(struct dasd_device * device,struct dasd_ccw_req * cqr)1904 static void __dasd_process_cqr(struct dasd_device *device,
1905 struct dasd_ccw_req *cqr)
1906 {
1907 char errorstring[ERRORLENGTH];
1908
1909 switch (cqr->status) {
1910 case DASD_CQR_SUCCESS:
1911 cqr->status = DASD_CQR_DONE;
1912 break;
1913 case DASD_CQR_ERROR:
1914 cqr->status = DASD_CQR_NEED_ERP;
1915 break;
1916 case DASD_CQR_CLEARED:
1917 cqr->status = DASD_CQR_TERMINATED;
1918 break;
1919 default:
1920 /* internal error 12 - wrong cqr status*/
1921 snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
1922 dev_err(&device->cdev->dev,
1923 "An error occurred in the DASD device driver, "
1924 "reason=%s\n", errorstring);
1925 BUG();
1926 }
1927 if (cqr->callback)
1928 cqr->callback(cqr, cqr->callback_data);
1929 }
1930
1931 /*
1932 * the cqrs from the final queue are returned to the upper layer
1933 * by setting a dasd_block state and calling the callback function
1934 */
__dasd_device_process_final_queue(struct dasd_device * device,struct list_head * final_queue)1935 static void __dasd_device_process_final_queue(struct dasd_device *device,
1936 struct list_head *final_queue)
1937 {
1938 struct list_head *l, *n;
1939 struct dasd_ccw_req *cqr;
1940 struct dasd_block *block;
1941
1942 list_for_each_safe(l, n, final_queue) {
1943 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1944 list_del_init(&cqr->devlist);
1945 block = cqr->block;
1946 if (!block) {
1947 __dasd_process_cqr(device, cqr);
1948 } else {
1949 spin_lock_bh(&block->queue_lock);
1950 __dasd_process_cqr(device, cqr);
1951 spin_unlock_bh(&block->queue_lock);
1952 }
1953 }
1954 }
1955
1956 /*
1957 * check if device should be autoquiesced due to too many timeouts
1958 */
__dasd_device_check_autoquiesce_timeout(struct dasd_device * device,struct dasd_ccw_req * cqr)1959 static void __dasd_device_check_autoquiesce_timeout(struct dasd_device *device,
1960 struct dasd_ccw_req *cqr)
1961 {
1962 if ((device->default_retries - cqr->retries) >= device->aq_timeouts)
1963 dasd_handle_autoquiesce(device, cqr, DASD_EER_TIMEOUTS);
1964 }
1965
1966 /*
1967 * Take a look at the first request on the ccw queue and check
1968 * if it reached its expire time. If so, terminate the IO.
1969 */
__dasd_device_check_expire(struct dasd_device * device)1970 static void __dasd_device_check_expire(struct dasd_device *device)
1971 {
1972 struct dasd_ccw_req *cqr;
1973
1974 if (list_empty(&device->ccw_queue))
1975 return;
1976 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1977 if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
1978 (time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
1979 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
1980 /*
1981 * IO in safe offline processing should not
1982 * run out of retries
1983 */
1984 cqr->retries++;
1985 }
1986 if (device->discipline->term_IO(cqr) != 0) {
1987 /* Hmpf, try again in 5 sec */
1988 dev_err(&device->cdev->dev,
1989 "cqr %p timed out (%lus) but cannot be "
1990 "ended, retrying in 5 s\n",
1991 cqr, (cqr->expires/HZ));
1992 cqr->expires += 5*HZ;
1993 dasd_device_set_timer(device, 5*HZ);
1994 } else {
1995 dev_err(&device->cdev->dev,
1996 "cqr %p timed out (%lus), %i retries "
1997 "remaining\n", cqr, (cqr->expires/HZ),
1998 cqr->retries);
1999 }
2000 __dasd_device_check_autoquiesce_timeout(device, cqr);
2001 }
2002 }
2003
2004 /*
2005 * return 1 when device is not eligible for IO
2006 */
__dasd_device_is_unusable(struct dasd_device * device,struct dasd_ccw_req * cqr)2007 static int __dasd_device_is_unusable(struct dasd_device *device,
2008 struct dasd_ccw_req *cqr)
2009 {
2010 int mask = ~(DASD_STOPPED_DC_WAIT | DASD_STOPPED_NOSPC);
2011
2012 if (test_bit(DASD_FLAG_OFFLINE, &device->flags) &&
2013 !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
2014 /*
2015 * dasd is being set offline
2016 * but it is no safe offline where we have to allow I/O
2017 */
2018 return 1;
2019 }
2020 if (device->stopped) {
2021 if (device->stopped & mask) {
2022 /* stopped and CQR will not change that. */
2023 return 1;
2024 }
2025 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
2026 /* CQR is not able to change device to
2027 * operational. */
2028 return 1;
2029 }
2030 /* CQR required to get device operational. */
2031 }
2032 return 0;
2033 }
2034
2035 /*
2036 * Take a look at the first request on the ccw queue and check
2037 * if it needs to be started.
2038 */
__dasd_device_start_head(struct dasd_device * device)2039 static void __dasd_device_start_head(struct dasd_device *device)
2040 {
2041 struct dasd_ccw_req *cqr;
2042 int rc;
2043
2044 if (list_empty(&device->ccw_queue))
2045 return;
2046 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2047 if (cqr->status != DASD_CQR_QUEUED)
2048 return;
2049 /* if device is not usable return request to upper layer */
2050 if (__dasd_device_is_unusable(device, cqr)) {
2051 cqr->intrc = -EAGAIN;
2052 cqr->status = DASD_CQR_CLEARED;
2053 dasd_schedule_device_bh(device);
2054 return;
2055 }
2056
2057 rc = device->discipline->start_IO(cqr);
2058 if (rc == 0)
2059 dasd_device_set_timer(device, cqr->expires);
2060 else if (rc == -EACCES) {
2061 dasd_schedule_device_bh(device);
2062 } else
2063 /* Hmpf, try again in 1/2 sec */
2064 dasd_device_set_timer(device, 50);
2065 }
2066
__dasd_device_check_path_events(struct dasd_device * device)2067 static void __dasd_device_check_path_events(struct dasd_device *device)
2068 {
2069 __u8 tbvpm, fcsecpm;
2070 int rc;
2071
2072 tbvpm = dasd_path_get_tbvpm(device);
2073 fcsecpm = dasd_path_get_fcsecpm(device);
2074
2075 if (!tbvpm && !fcsecpm)
2076 return;
2077
2078 if (device->stopped & ~(DASD_STOPPED_DC_WAIT))
2079 return;
2080
2081 dasd_path_clear_all_verify(device);
2082 dasd_path_clear_all_fcsec(device);
2083
2084 rc = device->discipline->pe_handler(device, tbvpm, fcsecpm);
2085 if (rc) {
2086 dasd_path_add_tbvpm(device, tbvpm);
2087 dasd_path_add_fcsecpm(device, fcsecpm);
2088 dasd_device_set_timer(device, 50);
2089 }
2090 };
2091
2092 /*
2093 * Go through all request on the dasd_device request queue,
2094 * terminate them on the cdev if necessary, and return them to the
2095 * submitting layer via callback.
2096 * Note:
2097 * Make sure that all 'submitting layers' still exist when
2098 * this function is called!. In other words, when 'device' is a base
2099 * device then all block layer requests must have been removed before
2100 * via dasd_flush_block_queue.
2101 */
dasd_flush_device_queue(struct dasd_device * device)2102 int dasd_flush_device_queue(struct dasd_device *device)
2103 {
2104 struct dasd_ccw_req *cqr, *n;
2105 int rc;
2106 struct list_head flush_queue;
2107
2108 INIT_LIST_HEAD(&flush_queue);
2109 spin_lock_irq(get_ccwdev_lock(device->cdev));
2110 rc = 0;
2111 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
2112 /* Check status and move request to flush_queue */
2113 switch (cqr->status) {
2114 case DASD_CQR_IN_IO:
2115 rc = device->discipline->term_IO(cqr);
2116 if (rc) {
2117 /* unable to terminate requeust */
2118 dev_err(&device->cdev->dev,
2119 "Flushing the DASD request queue "
2120 "failed for request %p\n", cqr);
2121 /* stop flush processing */
2122 goto finished;
2123 }
2124 break;
2125 case DASD_CQR_QUEUED:
2126 cqr->stopclk = get_tod_clock();
2127 cqr->status = DASD_CQR_CLEARED;
2128 break;
2129 default: /* no need to modify the others */
2130 break;
2131 }
2132 list_move_tail(&cqr->devlist, &flush_queue);
2133 }
2134 finished:
2135 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2136 /*
2137 * After this point all requests must be in state CLEAR_PENDING,
2138 * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
2139 * one of the others.
2140 */
2141 list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
2142 wait_event(dasd_flush_wq,
2143 (cqr->status != DASD_CQR_CLEAR_PENDING));
2144 /*
2145 * Now set each request back to TERMINATED, DONE or NEED_ERP
2146 * and call the callback function of flushed requests
2147 */
2148 __dasd_device_process_final_queue(device, &flush_queue);
2149 return rc;
2150 }
2151 EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
2152
2153 /*
2154 * Acquire the device lock and process queues for the device.
2155 */
dasd_device_tasklet(unsigned long data)2156 static void dasd_device_tasklet(unsigned long data)
2157 {
2158 struct dasd_device *device = (struct dasd_device *) data;
2159 struct list_head final_queue;
2160
2161 atomic_set (&device->tasklet_scheduled, 0);
2162 INIT_LIST_HEAD(&final_queue);
2163 spin_lock_irq(get_ccwdev_lock(device->cdev));
2164 /* Check expire time of first request on the ccw queue. */
2165 __dasd_device_check_expire(device);
2166 /* find final requests on ccw queue */
2167 __dasd_device_process_ccw_queue(device, &final_queue);
2168 __dasd_device_check_path_events(device);
2169 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2170 /* Now call the callback function of requests with final status */
2171 __dasd_device_process_final_queue(device, &final_queue);
2172 spin_lock_irq(get_ccwdev_lock(device->cdev));
2173 /* Now check if the head of the ccw queue needs to be started. */
2174 __dasd_device_start_head(device);
2175 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2176 if (waitqueue_active(&shutdown_waitq))
2177 wake_up(&shutdown_waitq);
2178 dasd_put_device(device);
2179 }
2180
2181 /*
2182 * Schedules a call to dasd_tasklet over the device tasklet.
2183 */
dasd_schedule_device_bh(struct dasd_device * device)2184 void dasd_schedule_device_bh(struct dasd_device *device)
2185 {
2186 /* Protect against rescheduling. */
2187 if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
2188 return;
2189 dasd_get_device(device);
2190 tasklet_hi_schedule(&device->tasklet);
2191 }
2192 EXPORT_SYMBOL(dasd_schedule_device_bh);
2193
dasd_device_set_stop_bits(struct dasd_device * device,int bits)2194 void dasd_device_set_stop_bits(struct dasd_device *device, int bits)
2195 {
2196 device->stopped |= bits;
2197 }
2198 EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits);
2199
dasd_device_remove_stop_bits(struct dasd_device * device,int bits)2200 void dasd_device_remove_stop_bits(struct dasd_device *device, int bits)
2201 {
2202 device->stopped &= ~bits;
2203 if (!device->stopped)
2204 wake_up(&generic_waitq);
2205 }
2206 EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits);
2207
2208 /*
2209 * Queue a request to the head of the device ccw_queue.
2210 * Start the I/O if possible.
2211 */
dasd_add_request_head(struct dasd_ccw_req * cqr)2212 void dasd_add_request_head(struct dasd_ccw_req *cqr)
2213 {
2214 struct dasd_device *device;
2215 unsigned long flags;
2216
2217 device = cqr->startdev;
2218 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2219 cqr->status = DASD_CQR_QUEUED;
2220 list_add(&cqr->devlist, &device->ccw_queue);
2221 /* let the bh start the request to keep them in order */
2222 dasd_schedule_device_bh(device);
2223 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2224 }
2225 EXPORT_SYMBOL(dasd_add_request_head);
2226
2227 /*
2228 * Queue a request to the tail of the device ccw_queue.
2229 * Start the I/O if possible.
2230 */
dasd_add_request_tail(struct dasd_ccw_req * cqr)2231 void dasd_add_request_tail(struct dasd_ccw_req *cqr)
2232 {
2233 struct dasd_device *device;
2234 unsigned long flags;
2235
2236 device = cqr->startdev;
2237 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2238 cqr->status = DASD_CQR_QUEUED;
2239 list_add_tail(&cqr->devlist, &device->ccw_queue);
2240 /* let the bh start the request to keep them in order */
2241 dasd_schedule_device_bh(device);
2242 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2243 }
2244 EXPORT_SYMBOL(dasd_add_request_tail);
2245
2246 /*
2247 * Wakeup helper for the 'sleep_on' functions.
2248 */
dasd_wakeup_cb(struct dasd_ccw_req * cqr,void * data)2249 void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
2250 {
2251 spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2252 cqr->callback_data = DASD_SLEEPON_END_TAG;
2253 spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2254 wake_up(&generic_waitq);
2255 }
2256 EXPORT_SYMBOL_GPL(dasd_wakeup_cb);
2257
_wait_for_wakeup(struct dasd_ccw_req * cqr)2258 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
2259 {
2260 struct dasd_device *device;
2261 int rc;
2262
2263 device = cqr->startdev;
2264 spin_lock_irq(get_ccwdev_lock(device->cdev));
2265 rc = (cqr->callback_data == DASD_SLEEPON_END_TAG);
2266 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2267 return rc;
2268 }
2269
2270 /*
2271 * checks if error recovery is necessary, returns 1 if yes, 0 otherwise.
2272 */
__dasd_sleep_on_erp(struct dasd_ccw_req * cqr)2273 static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr)
2274 {
2275 struct dasd_device *device;
2276 dasd_erp_fn_t erp_fn;
2277
2278 if (cqr->status == DASD_CQR_FILLED)
2279 return 0;
2280 device = cqr->startdev;
2281 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2282 if (cqr->status == DASD_CQR_TERMINATED) {
2283 device->discipline->handle_terminated_request(cqr);
2284 return 1;
2285 }
2286 if (cqr->status == DASD_CQR_NEED_ERP) {
2287 erp_fn = device->discipline->erp_action(cqr);
2288 erp_fn(cqr);
2289 return 1;
2290 }
2291 if (cqr->status == DASD_CQR_FAILED)
2292 dasd_log_sense(cqr, &cqr->irb);
2293 if (cqr->refers) {
2294 __dasd_process_erp(device, cqr);
2295 return 1;
2296 }
2297 }
2298 return 0;
2299 }
2300
__dasd_sleep_on_loop_condition(struct dasd_ccw_req * cqr)2301 static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr)
2302 {
2303 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2304 if (cqr->refers) /* erp is not done yet */
2305 return 1;
2306 return ((cqr->status != DASD_CQR_DONE) &&
2307 (cqr->status != DASD_CQR_FAILED));
2308 } else
2309 return (cqr->status == DASD_CQR_FILLED);
2310 }
2311
_dasd_sleep_on(struct dasd_ccw_req * maincqr,int interruptible)2312 static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
2313 {
2314 struct dasd_device *device;
2315 int rc;
2316 struct list_head ccw_queue;
2317 struct dasd_ccw_req *cqr;
2318
2319 INIT_LIST_HEAD(&ccw_queue);
2320 maincqr->status = DASD_CQR_FILLED;
2321 device = maincqr->startdev;
2322 list_add(&maincqr->blocklist, &ccw_queue);
2323 for (cqr = maincqr; __dasd_sleep_on_loop_condition(cqr);
2324 cqr = list_first_entry(&ccw_queue,
2325 struct dasd_ccw_req, blocklist)) {
2326
2327 if (__dasd_sleep_on_erp(cqr))
2328 continue;
2329 if (cqr->status != DASD_CQR_FILLED) /* could be failed */
2330 continue;
2331 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2332 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2333 cqr->status = DASD_CQR_FAILED;
2334 cqr->intrc = -EPERM;
2335 continue;
2336 }
2337 /* Non-temporary stop condition will trigger fail fast */
2338 if (device->stopped & ~DASD_STOPPED_PENDING &&
2339 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2340 !dasd_eer_enabled(device) && device->aq_mask == 0) {
2341 cqr->status = DASD_CQR_FAILED;
2342 cqr->intrc = -ENOLINK;
2343 continue;
2344 }
2345 /*
2346 * Don't try to start requests if device is in
2347 * offline processing, it might wait forever
2348 */
2349 if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
2350 cqr->status = DASD_CQR_FAILED;
2351 cqr->intrc = -ENODEV;
2352 continue;
2353 }
2354 /*
2355 * Don't try to start requests if device is stopped
2356 * except path verification requests
2357 */
2358 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
2359 if (interruptible) {
2360 rc = wait_event_interruptible(
2361 generic_waitq, !(device->stopped));
2362 if (rc == -ERESTARTSYS) {
2363 cqr->status = DASD_CQR_FAILED;
2364 maincqr->intrc = rc;
2365 continue;
2366 }
2367 } else
2368 wait_event(generic_waitq, !(device->stopped));
2369 }
2370 if (!cqr->callback)
2371 cqr->callback = dasd_wakeup_cb;
2372
2373 cqr->callback_data = DASD_SLEEPON_START_TAG;
2374 dasd_add_request_tail(cqr);
2375 if (interruptible) {
2376 rc = wait_event_interruptible(
2377 generic_waitq, _wait_for_wakeup(cqr));
2378 if (rc == -ERESTARTSYS) {
2379 dasd_cancel_req(cqr);
2380 /* wait (non-interruptible) for final status */
2381 wait_event(generic_waitq,
2382 _wait_for_wakeup(cqr));
2383 cqr->status = DASD_CQR_FAILED;
2384 maincqr->intrc = rc;
2385 continue;
2386 }
2387 } else
2388 wait_event(generic_waitq, _wait_for_wakeup(cqr));
2389 }
2390
2391 maincqr->endclk = get_tod_clock();
2392 if ((maincqr->status != DASD_CQR_DONE) &&
2393 (maincqr->intrc != -ERESTARTSYS))
2394 dasd_log_sense(maincqr, &maincqr->irb);
2395 if (maincqr->status == DASD_CQR_DONE)
2396 rc = 0;
2397 else if (maincqr->intrc)
2398 rc = maincqr->intrc;
2399 else
2400 rc = -EIO;
2401 return rc;
2402 }
2403
_wait_for_wakeup_queue(struct list_head * ccw_queue)2404 static inline int _wait_for_wakeup_queue(struct list_head *ccw_queue)
2405 {
2406 struct dasd_ccw_req *cqr;
2407
2408 list_for_each_entry(cqr, ccw_queue, blocklist) {
2409 if (cqr->callback_data != DASD_SLEEPON_END_TAG)
2410 return 0;
2411 }
2412
2413 return 1;
2414 }
2415
_dasd_sleep_on_queue(struct list_head * ccw_queue,int interruptible)2416 static int _dasd_sleep_on_queue(struct list_head *ccw_queue, int interruptible)
2417 {
2418 struct dasd_device *device;
2419 struct dasd_ccw_req *cqr, *n;
2420 u8 *sense = NULL;
2421 int rc;
2422
2423 retry:
2424 list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
2425 device = cqr->startdev;
2426 if (cqr->status != DASD_CQR_FILLED) /*could be failed*/
2427 continue;
2428
2429 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2430 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2431 cqr->status = DASD_CQR_FAILED;
2432 cqr->intrc = -EPERM;
2433 continue;
2434 }
2435 /*Non-temporary stop condition will trigger fail fast*/
2436 if (device->stopped & ~DASD_STOPPED_PENDING &&
2437 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2438 !dasd_eer_enabled(device)) {
2439 cqr->status = DASD_CQR_FAILED;
2440 cqr->intrc = -EAGAIN;
2441 continue;
2442 }
2443
2444 /*Don't try to start requests if device is stopped*/
2445 if (interruptible) {
2446 rc = wait_event_interruptible(
2447 generic_waitq, !device->stopped);
2448 if (rc == -ERESTARTSYS) {
2449 cqr->status = DASD_CQR_FAILED;
2450 cqr->intrc = rc;
2451 continue;
2452 }
2453 } else
2454 wait_event(generic_waitq, !(device->stopped));
2455
2456 if (!cqr->callback)
2457 cqr->callback = dasd_wakeup_cb;
2458 cqr->callback_data = DASD_SLEEPON_START_TAG;
2459 dasd_add_request_tail(cqr);
2460 }
2461
2462 wait_event(generic_waitq, _wait_for_wakeup_queue(ccw_queue));
2463
2464 rc = 0;
2465 list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
2466 /*
2467 * In some cases the 'File Protected' or 'Incorrect Length'
2468 * error might be expected and error recovery would be
2469 * unnecessary in these cases. Check if the according suppress
2470 * bit is set.
2471 */
2472 sense = dasd_get_sense(&cqr->irb);
2473 if (sense && sense[1] & SNS1_FILE_PROTECTED &&
2474 test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags))
2475 continue;
2476 if (scsw_cstat(&cqr->irb.scsw) == 0x40 &&
2477 test_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags))
2478 continue;
2479
2480 /*
2481 * for alias devices simplify error recovery and
2482 * return to upper layer
2483 * do not skip ERP requests
2484 */
2485 if (cqr->startdev != cqr->basedev && !cqr->refers &&
2486 (cqr->status == DASD_CQR_TERMINATED ||
2487 cqr->status == DASD_CQR_NEED_ERP))
2488 return -EAGAIN;
2489
2490 /* normal recovery for basedev IO */
2491 if (__dasd_sleep_on_erp(cqr))
2492 /* handle erp first */
2493 goto retry;
2494 }
2495
2496 return 0;
2497 }
2498
2499 /*
2500 * Queue a request to the tail of the device ccw_queue and wait for
2501 * it's completion.
2502 */
dasd_sleep_on(struct dasd_ccw_req * cqr)2503 int dasd_sleep_on(struct dasd_ccw_req *cqr)
2504 {
2505 return _dasd_sleep_on(cqr, 0);
2506 }
2507 EXPORT_SYMBOL(dasd_sleep_on);
2508
2509 /*
2510 * Start requests from a ccw_queue and wait for their completion.
2511 */
dasd_sleep_on_queue(struct list_head * ccw_queue)2512 int dasd_sleep_on_queue(struct list_head *ccw_queue)
2513 {
2514 return _dasd_sleep_on_queue(ccw_queue, 0);
2515 }
2516 EXPORT_SYMBOL(dasd_sleep_on_queue);
2517
2518 /*
2519 * Start requests from a ccw_queue and wait interruptible for their completion.
2520 */
dasd_sleep_on_queue_interruptible(struct list_head * ccw_queue)2521 int dasd_sleep_on_queue_interruptible(struct list_head *ccw_queue)
2522 {
2523 return _dasd_sleep_on_queue(ccw_queue, 1);
2524 }
2525 EXPORT_SYMBOL(dasd_sleep_on_queue_interruptible);
2526
2527 /*
2528 * Queue a request to the tail of the device ccw_queue and wait
2529 * interruptible for it's completion.
2530 */
dasd_sleep_on_interruptible(struct dasd_ccw_req * cqr)2531 int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
2532 {
2533 return _dasd_sleep_on(cqr, 1);
2534 }
2535 EXPORT_SYMBOL(dasd_sleep_on_interruptible);
2536
2537 /*
2538 * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
2539 * for eckd devices) the currently running request has to be terminated
2540 * and be put back to status queued, before the special request is added
2541 * to the head of the queue. Then the special request is waited on normally.
2542 */
_dasd_term_running_cqr(struct dasd_device * device)2543 static inline int _dasd_term_running_cqr(struct dasd_device *device)
2544 {
2545 struct dasd_ccw_req *cqr;
2546 int rc;
2547
2548 if (list_empty(&device->ccw_queue))
2549 return 0;
2550 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2551 rc = device->discipline->term_IO(cqr);
2552 if (!rc)
2553 /*
2554 * CQR terminated because a more important request is pending.
2555 * Undo decreasing of retry counter because this is
2556 * not an error case.
2557 */
2558 cqr->retries++;
2559 return rc;
2560 }
2561
dasd_sleep_on_immediatly(struct dasd_ccw_req * cqr)2562 int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
2563 {
2564 struct dasd_device *device;
2565 int rc;
2566
2567 device = cqr->startdev;
2568 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2569 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2570 cqr->status = DASD_CQR_FAILED;
2571 cqr->intrc = -EPERM;
2572 return -EIO;
2573 }
2574 spin_lock_irq(get_ccwdev_lock(device->cdev));
2575 rc = _dasd_term_running_cqr(device);
2576 if (rc) {
2577 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2578 return rc;
2579 }
2580 cqr->callback = dasd_wakeup_cb;
2581 cqr->callback_data = DASD_SLEEPON_START_TAG;
2582 cqr->status = DASD_CQR_QUEUED;
2583 /*
2584 * add new request as second
2585 * first the terminated cqr needs to be finished
2586 */
2587 list_add(&cqr->devlist, device->ccw_queue.next);
2588
2589 /* let the bh start the request to keep them in order */
2590 dasd_schedule_device_bh(device);
2591
2592 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2593
2594 wait_event(generic_waitq, _wait_for_wakeup(cqr));
2595
2596 if (cqr->status == DASD_CQR_DONE)
2597 rc = 0;
2598 else if (cqr->intrc)
2599 rc = cqr->intrc;
2600 else
2601 rc = -EIO;
2602
2603 /* kick tasklets */
2604 dasd_schedule_device_bh(device);
2605 if (device->block)
2606 dasd_schedule_block_bh(device->block);
2607
2608 return rc;
2609 }
2610 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
2611
2612 /*
2613 * Cancels a request that was started with dasd_sleep_on_req.
2614 * This is useful to timeout requests. The request will be
2615 * terminated if it is currently in i/o.
2616 * Returns 0 if request termination was successful
2617 * negative error code if termination failed
2618 * Cancellation of a request is an asynchronous operation! The calling
2619 * function has to wait until the request is properly returned via callback.
2620 */
__dasd_cancel_req(struct dasd_ccw_req * cqr)2621 static int __dasd_cancel_req(struct dasd_ccw_req *cqr)
2622 {
2623 struct dasd_device *device = cqr->startdev;
2624 int rc = 0;
2625
2626 switch (cqr->status) {
2627 case DASD_CQR_QUEUED:
2628 /* request was not started - just set to cleared */
2629 cqr->status = DASD_CQR_CLEARED;
2630 break;
2631 case DASD_CQR_IN_IO:
2632 /* request in IO - terminate IO and release again */
2633 rc = device->discipline->term_IO(cqr);
2634 if (rc) {
2635 dev_err(&device->cdev->dev,
2636 "Cancelling request %p failed with rc=%d\n",
2637 cqr, rc);
2638 } else {
2639 cqr->stopclk = get_tod_clock();
2640 }
2641 break;
2642 default: /* already finished or clear pending - do nothing */
2643 break;
2644 }
2645 dasd_schedule_device_bh(device);
2646 return rc;
2647 }
2648
dasd_cancel_req(struct dasd_ccw_req * cqr)2649 int dasd_cancel_req(struct dasd_ccw_req *cqr)
2650 {
2651 struct dasd_device *device = cqr->startdev;
2652 unsigned long flags;
2653 int rc;
2654
2655 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2656 rc = __dasd_cancel_req(cqr);
2657 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2658 return rc;
2659 }
2660
2661 /*
2662 * SECTION: Operations of the dasd_block layer.
2663 */
2664
2665 /*
2666 * Timeout function for dasd_block. This is used when the block layer
2667 * is waiting for something that may not come reliably, (e.g. a state
2668 * change interrupt)
2669 */
dasd_block_timeout(struct timer_list * t)2670 static void dasd_block_timeout(struct timer_list *t)
2671 {
2672 unsigned long flags;
2673 struct dasd_block *block;
2674
2675 block = from_timer(block, t, timer);
2676 spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
2677 /* re-activate request queue */
2678 dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING);
2679 spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
2680 dasd_schedule_block_bh(block);
2681 blk_mq_run_hw_queues(block->gdp->queue, true);
2682 }
2683
2684 /*
2685 * Setup timeout for a dasd_block in jiffies.
2686 */
dasd_block_set_timer(struct dasd_block * block,int expires)2687 void dasd_block_set_timer(struct dasd_block *block, int expires)
2688 {
2689 if (expires == 0)
2690 del_timer(&block->timer);
2691 else
2692 mod_timer(&block->timer, jiffies + expires);
2693 }
2694 EXPORT_SYMBOL(dasd_block_set_timer);
2695
2696 /*
2697 * Clear timeout for a dasd_block.
2698 */
dasd_block_clear_timer(struct dasd_block * block)2699 void dasd_block_clear_timer(struct dasd_block *block)
2700 {
2701 del_timer(&block->timer);
2702 }
2703 EXPORT_SYMBOL(dasd_block_clear_timer);
2704
2705 /*
2706 * Process finished error recovery ccw.
2707 */
__dasd_process_erp(struct dasd_device * device,struct dasd_ccw_req * cqr)2708 static void __dasd_process_erp(struct dasd_device *device,
2709 struct dasd_ccw_req *cqr)
2710 {
2711 dasd_erp_fn_t erp_fn;
2712
2713 if (cqr->status == DASD_CQR_DONE)
2714 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
2715 else
2716 dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
2717 erp_fn = device->discipline->erp_postaction(cqr);
2718 erp_fn(cqr);
2719 }
2720
__dasd_cleanup_cqr(struct dasd_ccw_req * cqr)2721 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
2722 {
2723 struct request *req;
2724 blk_status_t error = BLK_STS_OK;
2725 unsigned int proc_bytes;
2726 int status;
2727
2728 req = (struct request *) cqr->callback_data;
2729 dasd_profile_end(cqr->block, cqr, req);
2730
2731 proc_bytes = cqr->proc_bytes;
2732 status = cqr->block->base->discipline->free_cp(cqr, req);
2733 if (status < 0)
2734 error = errno_to_blk_status(status);
2735 else if (status == 0) {
2736 switch (cqr->intrc) {
2737 case -EPERM:
2738 /*
2739 * DASD doesn't implement SCSI/NVMe reservations, but it
2740 * implements a locking scheme similar to them. We
2741 * return this error when we no longer have the lock.
2742 */
2743 error = BLK_STS_RESV_CONFLICT;
2744 break;
2745 case -ENOLINK:
2746 error = BLK_STS_TRANSPORT;
2747 break;
2748 case -ETIMEDOUT:
2749 error = BLK_STS_TIMEOUT;
2750 break;
2751 default:
2752 error = BLK_STS_IOERR;
2753 break;
2754 }
2755 }
2756
2757 /*
2758 * We need to take care for ETIMEDOUT errors here since the
2759 * complete callback does not get called in this case.
2760 * Take care of all errors here and avoid additional code to
2761 * transfer the error value to the complete callback.
2762 */
2763 if (error) {
2764 blk_mq_end_request(req, error);
2765 blk_mq_run_hw_queues(req->q, true);
2766 } else {
2767 /*
2768 * Partial completed requests can happen with ESE devices.
2769 * During read we might have gotten a NRF error and have to
2770 * complete a request partially.
2771 */
2772 if (proc_bytes) {
2773 blk_update_request(req, BLK_STS_OK, proc_bytes);
2774 blk_mq_requeue_request(req, true);
2775 } else if (likely(!blk_should_fake_timeout(req->q))) {
2776 blk_mq_complete_request(req);
2777 }
2778 }
2779 }
2780
2781 /*
2782 * Process ccw request queue.
2783 */
__dasd_process_block_ccw_queue(struct dasd_block * block,struct list_head * final_queue)2784 static void __dasd_process_block_ccw_queue(struct dasd_block *block,
2785 struct list_head *final_queue)
2786 {
2787 struct list_head *l, *n;
2788 struct dasd_ccw_req *cqr;
2789 dasd_erp_fn_t erp_fn;
2790 unsigned long flags;
2791 struct dasd_device *base = block->base;
2792
2793 restart:
2794 /* Process request with final status. */
2795 list_for_each_safe(l, n, &block->ccw_queue) {
2796 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2797 if (cqr->status != DASD_CQR_DONE &&
2798 cqr->status != DASD_CQR_FAILED &&
2799 cqr->status != DASD_CQR_NEED_ERP &&
2800 cqr->status != DASD_CQR_TERMINATED)
2801 continue;
2802
2803 if (cqr->status == DASD_CQR_TERMINATED) {
2804 base->discipline->handle_terminated_request(cqr);
2805 goto restart;
2806 }
2807
2808 /* Process requests that may be recovered */
2809 if (cqr->status == DASD_CQR_NEED_ERP) {
2810 erp_fn = base->discipline->erp_action(cqr);
2811 if (IS_ERR(erp_fn(cqr)))
2812 continue;
2813 goto restart;
2814 }
2815
2816 /* log sense for fatal error */
2817 if (cqr->status == DASD_CQR_FAILED) {
2818 dasd_log_sense(cqr, &cqr->irb);
2819 }
2820
2821 /*
2822 * First call extended error reporting and check for autoquiesce
2823 */
2824 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
2825 if (cqr->status == DASD_CQR_FAILED &&
2826 dasd_handle_autoquiesce(base, cqr, DASD_EER_FATALERROR)) {
2827 cqr->status = DASD_CQR_FILLED;
2828 cqr->retries = 255;
2829 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
2830 goto restart;
2831 }
2832 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
2833
2834 /* Process finished ERP request. */
2835 if (cqr->refers) {
2836 __dasd_process_erp(base, cqr);
2837 goto restart;
2838 }
2839
2840 /* Rechain finished requests to final queue */
2841 cqr->endclk = get_tod_clock();
2842 list_move_tail(&cqr->blocklist, final_queue);
2843 }
2844 }
2845
dasd_return_cqr_cb(struct dasd_ccw_req * cqr,void * data)2846 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
2847 {
2848 dasd_schedule_block_bh(cqr->block);
2849 }
2850
__dasd_block_start_head(struct dasd_block * block)2851 static void __dasd_block_start_head(struct dasd_block *block)
2852 {
2853 struct dasd_ccw_req *cqr;
2854
2855 if (list_empty(&block->ccw_queue))
2856 return;
2857 /* We allways begin with the first requests on the queue, as some
2858 * of previously started requests have to be enqueued on a
2859 * dasd_device again for error recovery.
2860 */
2861 list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
2862 if (cqr->status != DASD_CQR_FILLED)
2863 continue;
2864 if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) &&
2865 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2866 cqr->status = DASD_CQR_FAILED;
2867 cqr->intrc = -EPERM;
2868 dasd_schedule_block_bh(block);
2869 continue;
2870 }
2871 /* Non-temporary stop condition will trigger fail fast */
2872 if (block->base->stopped & ~DASD_STOPPED_PENDING &&
2873 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2874 !dasd_eer_enabled(block->base) && block->base->aq_mask == 0) {
2875 cqr->status = DASD_CQR_FAILED;
2876 cqr->intrc = -ENOLINK;
2877 dasd_schedule_block_bh(block);
2878 continue;
2879 }
2880 /* Don't try to start requests if device is stopped */
2881 if (block->base->stopped)
2882 return;
2883
2884 /* just a fail safe check, should not happen */
2885 if (!cqr->startdev)
2886 cqr->startdev = block->base;
2887
2888 /* make sure that the requests we submit find their way back */
2889 cqr->callback = dasd_return_cqr_cb;
2890
2891 dasd_add_request_tail(cqr);
2892 }
2893 }
2894
2895 /*
2896 * Central dasd_block layer routine. Takes requests from the generic
2897 * block layer request queue, creates ccw requests, enqueues them on
2898 * a dasd_device and processes ccw requests that have been returned.
2899 */
dasd_block_tasklet(unsigned long data)2900 static void dasd_block_tasklet(unsigned long data)
2901 {
2902 struct dasd_block *block = (struct dasd_block *) data;
2903 struct list_head final_queue;
2904 struct list_head *l, *n;
2905 struct dasd_ccw_req *cqr;
2906 struct dasd_queue *dq;
2907
2908 atomic_set(&block->tasklet_scheduled, 0);
2909 INIT_LIST_HEAD(&final_queue);
2910 spin_lock_irq(&block->queue_lock);
2911 /* Finish off requests on ccw queue */
2912 __dasd_process_block_ccw_queue(block, &final_queue);
2913 spin_unlock_irq(&block->queue_lock);
2914
2915 /* Now call the callback function of requests with final status */
2916 list_for_each_safe(l, n, &final_queue) {
2917 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2918 dq = cqr->dq;
2919 spin_lock_irq(&dq->lock);
2920 list_del_init(&cqr->blocklist);
2921 __dasd_cleanup_cqr(cqr);
2922 spin_unlock_irq(&dq->lock);
2923 }
2924
2925 spin_lock_irq(&block->queue_lock);
2926 /* Now check if the head of the ccw queue needs to be started. */
2927 __dasd_block_start_head(block);
2928 spin_unlock_irq(&block->queue_lock);
2929
2930 if (waitqueue_active(&shutdown_waitq))
2931 wake_up(&shutdown_waitq);
2932 dasd_put_device(block->base);
2933 }
2934
_dasd_wake_block_flush_cb(struct dasd_ccw_req * cqr,void * data)2935 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
2936 {
2937 wake_up(&dasd_flush_wq);
2938 }
2939
2940 /*
2941 * Requeue a request back to the block request queue
2942 * only works for block requests
2943 */
_dasd_requeue_request(struct dasd_ccw_req * cqr)2944 static void _dasd_requeue_request(struct dasd_ccw_req *cqr)
2945 {
2946 struct request *req;
2947
2948 /*
2949 * If the request is an ERP request there is nothing to requeue.
2950 * This will be done with the remaining original request.
2951 */
2952 if (cqr->refers)
2953 return;
2954 spin_lock_irq(&cqr->dq->lock);
2955 req = (struct request *) cqr->callback_data;
2956 blk_mq_requeue_request(req, true);
2957 spin_unlock_irq(&cqr->dq->lock);
2958
2959 return;
2960 }
2961
_dasd_requests_to_flushqueue(struct dasd_block * block,struct list_head * flush_queue)2962 static int _dasd_requests_to_flushqueue(struct dasd_block *block,
2963 struct list_head *flush_queue)
2964 {
2965 struct dasd_ccw_req *cqr, *n;
2966 unsigned long flags;
2967 int rc, i;
2968
2969 spin_lock_irqsave(&block->queue_lock, flags);
2970 rc = 0;
2971 restart:
2972 list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
2973 /* if this request currently owned by a dasd_device cancel it */
2974 if (cqr->status >= DASD_CQR_QUEUED)
2975 rc = dasd_cancel_req(cqr);
2976 if (rc < 0)
2977 break;
2978 /* Rechain request (including erp chain) so it won't be
2979 * touched by the dasd_block_tasklet anymore.
2980 * Replace the callback so we notice when the request
2981 * is returned from the dasd_device layer.
2982 */
2983 cqr->callback = _dasd_wake_block_flush_cb;
2984 for (i = 0; cqr; cqr = cqr->refers, i++)
2985 list_move_tail(&cqr->blocklist, flush_queue);
2986 if (i > 1)
2987 /* moved more than one request - need to restart */
2988 goto restart;
2989 }
2990 spin_unlock_irqrestore(&block->queue_lock, flags);
2991
2992 return rc;
2993 }
2994
2995 /*
2996 * Go through all request on the dasd_block request queue, cancel them
2997 * on the respective dasd_device, and return them to the generic
2998 * block layer.
2999 */
dasd_flush_block_queue(struct dasd_block * block)3000 static int dasd_flush_block_queue(struct dasd_block *block)
3001 {
3002 struct dasd_ccw_req *cqr, *n;
3003 struct list_head flush_queue;
3004 unsigned long flags;
3005 int rc;
3006
3007 INIT_LIST_HEAD(&flush_queue);
3008 rc = _dasd_requests_to_flushqueue(block, &flush_queue);
3009
3010 /* Now call the callback function of flushed requests */
3011 restart_cb:
3012 list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
3013 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
3014 /* Process finished ERP request. */
3015 if (cqr->refers) {
3016 spin_lock_bh(&block->queue_lock);
3017 __dasd_process_erp(block->base, cqr);
3018 spin_unlock_bh(&block->queue_lock);
3019 /* restart list_for_xx loop since dasd_process_erp
3020 * might remove multiple elements */
3021 goto restart_cb;
3022 }
3023 /* call the callback function */
3024 spin_lock_irqsave(&cqr->dq->lock, flags);
3025 cqr->endclk = get_tod_clock();
3026 list_del_init(&cqr->blocklist);
3027 __dasd_cleanup_cqr(cqr);
3028 spin_unlock_irqrestore(&cqr->dq->lock, flags);
3029 }
3030 return rc;
3031 }
3032
3033 /*
3034 * Schedules a call to dasd_tasklet over the device tasklet.
3035 */
dasd_schedule_block_bh(struct dasd_block * block)3036 void dasd_schedule_block_bh(struct dasd_block *block)
3037 {
3038 /* Protect against rescheduling. */
3039 if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
3040 return;
3041 /* life cycle of block is bound to it's base device */
3042 dasd_get_device(block->base);
3043 tasklet_hi_schedule(&block->tasklet);
3044 }
3045 EXPORT_SYMBOL(dasd_schedule_block_bh);
3046
3047
3048 /*
3049 * SECTION: external block device operations
3050 * (request queue handling, open, release, etc.)
3051 */
3052
3053 /*
3054 * Dasd request queue function. Called from ll_rw_blk.c
3055 */
do_dasd_request(struct blk_mq_hw_ctx * hctx,const struct blk_mq_queue_data * qd)3056 static blk_status_t do_dasd_request(struct blk_mq_hw_ctx *hctx,
3057 const struct blk_mq_queue_data *qd)
3058 {
3059 struct dasd_block *block = hctx->queue->queuedata;
3060 struct dasd_queue *dq = hctx->driver_data;
3061 struct request *req = qd->rq;
3062 struct dasd_device *basedev;
3063 struct dasd_ccw_req *cqr;
3064 blk_status_t rc = BLK_STS_OK;
3065
3066 basedev = block->base;
3067 spin_lock_irq(&dq->lock);
3068 if (basedev->state < DASD_STATE_READY ||
3069 test_bit(DASD_FLAG_OFFLINE, &basedev->flags)) {
3070 DBF_DEV_EVENT(DBF_ERR, basedev,
3071 "device not ready for request %p", req);
3072 rc = BLK_STS_IOERR;
3073 goto out;
3074 }
3075
3076 /*
3077 * if device is stopped do not fetch new requests
3078 * except failfast is active which will let requests fail
3079 * immediately in __dasd_block_start_head()
3080 */
3081 if (basedev->stopped && !(basedev->features & DASD_FEATURE_FAILFAST)) {
3082 DBF_DEV_EVENT(DBF_ERR, basedev,
3083 "device stopped request %p", req);
3084 rc = BLK_STS_RESOURCE;
3085 goto out;
3086 }
3087
3088 if (basedev->features & DASD_FEATURE_READONLY &&
3089 rq_data_dir(req) == WRITE) {
3090 DBF_DEV_EVENT(DBF_ERR, basedev,
3091 "Rejecting write request %p", req);
3092 rc = BLK_STS_IOERR;
3093 goto out;
3094 }
3095
3096 if (test_bit(DASD_FLAG_ABORTALL, &basedev->flags) &&
3097 (basedev->features & DASD_FEATURE_FAILFAST ||
3098 blk_noretry_request(req))) {
3099 DBF_DEV_EVENT(DBF_ERR, basedev,
3100 "Rejecting failfast request %p", req);
3101 rc = BLK_STS_IOERR;
3102 goto out;
3103 }
3104
3105 cqr = basedev->discipline->build_cp(basedev, block, req);
3106 if (IS_ERR(cqr)) {
3107 if (PTR_ERR(cqr) == -EBUSY ||
3108 PTR_ERR(cqr) == -ENOMEM ||
3109 PTR_ERR(cqr) == -EAGAIN) {
3110 rc = BLK_STS_RESOURCE;
3111 goto out;
3112 }
3113 DBF_DEV_EVENT(DBF_ERR, basedev,
3114 "CCW creation failed (rc=%ld) on request %p",
3115 PTR_ERR(cqr), req);
3116 rc = BLK_STS_IOERR;
3117 goto out;
3118 }
3119 /*
3120 * Note: callback is set to dasd_return_cqr_cb in
3121 * __dasd_block_start_head to cover erp requests as well
3122 */
3123 cqr->callback_data = req;
3124 cqr->status = DASD_CQR_FILLED;
3125 cqr->dq = dq;
3126
3127 blk_mq_start_request(req);
3128 spin_lock(&block->queue_lock);
3129 list_add_tail(&cqr->blocklist, &block->ccw_queue);
3130 INIT_LIST_HEAD(&cqr->devlist);
3131 dasd_profile_start(block, cqr, req);
3132 dasd_schedule_block_bh(block);
3133 spin_unlock(&block->queue_lock);
3134
3135 out:
3136 spin_unlock_irq(&dq->lock);
3137 return rc;
3138 }
3139
3140 /*
3141 * Block timeout callback, called from the block layer
3142 *
3143 * Return values:
3144 * BLK_EH_RESET_TIMER if the request should be left running
3145 * BLK_EH_DONE if the request is handled or terminated
3146 * by the driver.
3147 */
dasd_times_out(struct request * req)3148 enum blk_eh_timer_return dasd_times_out(struct request *req)
3149 {
3150 struct dasd_block *block = req->q->queuedata;
3151 struct dasd_device *device;
3152 struct dasd_ccw_req *cqr;
3153 unsigned long flags;
3154 int rc = 0;
3155
3156 cqr = blk_mq_rq_to_pdu(req);
3157 if (!cqr)
3158 return BLK_EH_DONE;
3159
3160 spin_lock_irqsave(&cqr->dq->lock, flags);
3161 device = cqr->startdev ? cqr->startdev : block->base;
3162 if (!device->blk_timeout) {
3163 spin_unlock_irqrestore(&cqr->dq->lock, flags);
3164 return BLK_EH_RESET_TIMER;
3165 }
3166 DBF_DEV_EVENT(DBF_WARNING, device,
3167 " dasd_times_out cqr %p status %x",
3168 cqr, cqr->status);
3169
3170 spin_lock(&block->queue_lock);
3171 spin_lock(get_ccwdev_lock(device->cdev));
3172 cqr->retries = -1;
3173 cqr->intrc = -ETIMEDOUT;
3174 if (cqr->status >= DASD_CQR_QUEUED) {
3175 rc = __dasd_cancel_req(cqr);
3176 } else if (cqr->status == DASD_CQR_FILLED ||
3177 cqr->status == DASD_CQR_NEED_ERP) {
3178 cqr->status = DASD_CQR_TERMINATED;
3179 } else if (cqr->status == DASD_CQR_IN_ERP) {
3180 struct dasd_ccw_req *searchcqr, *nextcqr, *tmpcqr;
3181
3182 list_for_each_entry_safe(searchcqr, nextcqr,
3183 &block->ccw_queue, blocklist) {
3184 tmpcqr = searchcqr;
3185 while (tmpcqr->refers)
3186 tmpcqr = tmpcqr->refers;
3187 if (tmpcqr != cqr)
3188 continue;
3189 /* searchcqr is an ERP request for cqr */
3190 searchcqr->retries = -1;
3191 searchcqr->intrc = -ETIMEDOUT;
3192 if (searchcqr->status >= DASD_CQR_QUEUED) {
3193 rc = __dasd_cancel_req(searchcqr);
3194 } else if ((searchcqr->status == DASD_CQR_FILLED) ||
3195 (searchcqr->status == DASD_CQR_NEED_ERP)) {
3196 searchcqr->status = DASD_CQR_TERMINATED;
3197 rc = 0;
3198 } else if (searchcqr->status == DASD_CQR_IN_ERP) {
3199 /*
3200 * Shouldn't happen; most recent ERP
3201 * request is at the front of queue
3202 */
3203 continue;
3204 }
3205 break;
3206 }
3207 }
3208 spin_unlock(get_ccwdev_lock(device->cdev));
3209 dasd_schedule_block_bh(block);
3210 spin_unlock(&block->queue_lock);
3211 spin_unlock_irqrestore(&cqr->dq->lock, flags);
3212
3213 return rc ? BLK_EH_RESET_TIMER : BLK_EH_DONE;
3214 }
3215
dasd_init_hctx(struct blk_mq_hw_ctx * hctx,void * data,unsigned int idx)3216 static int dasd_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
3217 unsigned int idx)
3218 {
3219 struct dasd_queue *dq = kzalloc(sizeof(*dq), GFP_KERNEL);
3220
3221 if (!dq)
3222 return -ENOMEM;
3223
3224 spin_lock_init(&dq->lock);
3225 hctx->driver_data = dq;
3226
3227 return 0;
3228 }
3229
dasd_exit_hctx(struct blk_mq_hw_ctx * hctx,unsigned int idx)3230 static void dasd_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int idx)
3231 {
3232 kfree(hctx->driver_data);
3233 hctx->driver_data = NULL;
3234 }
3235
dasd_request_done(struct request * req)3236 static void dasd_request_done(struct request *req)
3237 {
3238 blk_mq_end_request(req, 0);
3239 blk_mq_run_hw_queues(req->q, true);
3240 }
3241
3242 struct blk_mq_ops dasd_mq_ops = {
3243 .queue_rq = do_dasd_request,
3244 .complete = dasd_request_done,
3245 .timeout = dasd_times_out,
3246 .init_hctx = dasd_init_hctx,
3247 .exit_hctx = dasd_exit_hctx,
3248 };
3249
dasd_open(struct gendisk * disk,blk_mode_t mode)3250 static int dasd_open(struct gendisk *disk, blk_mode_t mode)
3251 {
3252 struct dasd_device *base;
3253 int rc;
3254
3255 base = dasd_device_from_gendisk(disk);
3256 if (!base)
3257 return -ENODEV;
3258
3259 atomic_inc(&base->block->open_count);
3260 if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
3261 rc = -ENODEV;
3262 goto unlock;
3263 }
3264
3265 if (!try_module_get(base->discipline->owner)) {
3266 rc = -EINVAL;
3267 goto unlock;
3268 }
3269
3270 if (dasd_probeonly) {
3271 dev_info(&base->cdev->dev,
3272 "Accessing the DASD failed because it is in "
3273 "probeonly mode\n");
3274 rc = -EPERM;
3275 goto out;
3276 }
3277
3278 if (base->state <= DASD_STATE_BASIC) {
3279 DBF_DEV_EVENT(DBF_ERR, base, " %s",
3280 " Cannot open unrecognized device");
3281 rc = -ENODEV;
3282 goto out;
3283 }
3284 if ((mode & BLK_OPEN_WRITE) &&
3285 (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) ||
3286 (base->features & DASD_FEATURE_READONLY))) {
3287 rc = -EROFS;
3288 goto out;
3289 }
3290 dasd_put_device(base);
3291 return 0;
3292
3293 out:
3294 module_put(base->discipline->owner);
3295 unlock:
3296 atomic_dec(&base->block->open_count);
3297 dasd_put_device(base);
3298 return rc;
3299 }
3300
dasd_release(struct gendisk * disk)3301 static void dasd_release(struct gendisk *disk)
3302 {
3303 struct dasd_device *base = dasd_device_from_gendisk(disk);
3304 if (base) {
3305 atomic_dec(&base->block->open_count);
3306 module_put(base->discipline->owner);
3307 dasd_put_device(base);
3308 }
3309 }
3310
3311 /*
3312 * Return disk geometry.
3313 */
dasd_getgeo(struct block_device * bdev,struct hd_geometry * geo)3314 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
3315 {
3316 struct dasd_device *base;
3317
3318 base = dasd_device_from_gendisk(bdev->bd_disk);
3319 if (!base)
3320 return -ENODEV;
3321
3322 if (!base->discipline ||
3323 !base->discipline->fill_geometry) {
3324 dasd_put_device(base);
3325 return -EINVAL;
3326 }
3327 base->discipline->fill_geometry(base->block, geo);
3328 geo->start = get_start_sect(bdev) >> base->block->s2b_shift;
3329 dasd_put_device(base);
3330 return 0;
3331 }
3332
3333 const struct block_device_operations
3334 dasd_device_operations = {
3335 .owner = THIS_MODULE,
3336 .open = dasd_open,
3337 .release = dasd_release,
3338 .ioctl = dasd_ioctl,
3339 .compat_ioctl = dasd_ioctl,
3340 .getgeo = dasd_getgeo,
3341 .set_read_only = dasd_set_read_only,
3342 };
3343
3344 /*******************************************************************************
3345 * end of block device operations
3346 */
3347
3348 static void
dasd_exit(void)3349 dasd_exit(void)
3350 {
3351 #ifdef CONFIG_PROC_FS
3352 dasd_proc_exit();
3353 #endif
3354 dasd_eer_exit();
3355 kmem_cache_destroy(dasd_page_cache);
3356 dasd_page_cache = NULL;
3357 dasd_gendisk_exit();
3358 dasd_devmap_exit();
3359 if (dasd_debug_area != NULL) {
3360 debug_unregister(dasd_debug_area);
3361 dasd_debug_area = NULL;
3362 }
3363 dasd_statistics_removeroot();
3364 }
3365
3366 /*
3367 * SECTION: common functions for ccw_driver use
3368 */
3369
3370 /*
3371 * Is the device read-only?
3372 * Note that this function does not report the setting of the
3373 * readonly device attribute, but how it is configured in z/VM.
3374 */
dasd_device_is_ro(struct dasd_device * device)3375 int dasd_device_is_ro(struct dasd_device *device)
3376 {
3377 struct ccw_dev_id dev_id;
3378 struct diag210 diag_data;
3379 int rc;
3380
3381 if (!MACHINE_IS_VM)
3382 return 0;
3383 ccw_device_get_id(device->cdev, &dev_id);
3384 memset(&diag_data, 0, sizeof(diag_data));
3385 diag_data.vrdcdvno = dev_id.devno;
3386 diag_data.vrdclen = sizeof(diag_data);
3387 rc = diag210(&diag_data);
3388 if (rc == 0 || rc == 2) {
3389 return diag_data.vrdcvfla & 0x80;
3390 } else {
3391 DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d",
3392 dev_id.devno, rc);
3393 return 0;
3394 }
3395 }
3396 EXPORT_SYMBOL_GPL(dasd_device_is_ro);
3397
dasd_generic_auto_online(void * data,async_cookie_t cookie)3398 static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
3399 {
3400 struct ccw_device *cdev = data;
3401 int ret;
3402
3403 ret = ccw_device_set_online(cdev);
3404 if (ret)
3405 pr_warn("%s: Setting the DASD online failed with rc=%d\n",
3406 dev_name(&cdev->dev), ret);
3407 }
3408
3409 /*
3410 * Initial attempt at a probe function. this can be simplified once
3411 * the other detection code is gone.
3412 */
dasd_generic_probe(struct ccw_device * cdev)3413 int dasd_generic_probe(struct ccw_device *cdev)
3414 {
3415 cdev->handler = &dasd_int_handler;
3416
3417 /*
3418 * Automatically online either all dasd devices (dasd_autodetect)
3419 * or all devices specified with dasd= parameters during
3420 * initial probe.
3421 */
3422 if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
3423 (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
3424 async_schedule(dasd_generic_auto_online, cdev);
3425 return 0;
3426 }
3427 EXPORT_SYMBOL_GPL(dasd_generic_probe);
3428
dasd_generic_free_discipline(struct dasd_device * device)3429 void dasd_generic_free_discipline(struct dasd_device *device)
3430 {
3431 /* Forget the discipline information. */
3432 if (device->discipline) {
3433 if (device->discipline->uncheck_device)
3434 device->discipline->uncheck_device(device);
3435 module_put(device->discipline->owner);
3436 device->discipline = NULL;
3437 }
3438 if (device->base_discipline) {
3439 module_put(device->base_discipline->owner);
3440 device->base_discipline = NULL;
3441 }
3442 }
3443 EXPORT_SYMBOL_GPL(dasd_generic_free_discipline);
3444
3445 /*
3446 * This will one day be called from a global not_oper handler.
3447 * It is also used by driver_unregister during module unload.
3448 */
dasd_generic_remove(struct ccw_device * cdev)3449 void dasd_generic_remove(struct ccw_device *cdev)
3450 {
3451 struct dasd_device *device;
3452 struct dasd_block *block;
3453
3454 device = dasd_device_from_cdev(cdev);
3455 if (IS_ERR(device))
3456 return;
3457
3458 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags) &&
3459 !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3460 /* Already doing offline processing */
3461 dasd_put_device(device);
3462 return;
3463 }
3464 /*
3465 * This device is removed unconditionally. Set offline
3466 * flag to prevent dasd_open from opening it while it is
3467 * no quite down yet.
3468 */
3469 dasd_set_target_state(device, DASD_STATE_NEW);
3470 cdev->handler = NULL;
3471 /* dasd_delete_device destroys the device reference. */
3472 block = device->block;
3473 dasd_delete_device(device);
3474 /*
3475 * life cycle of block is bound to device, so delete it after
3476 * device was safely removed
3477 */
3478 if (block)
3479 dasd_free_block(block);
3480 }
3481 EXPORT_SYMBOL_GPL(dasd_generic_remove);
3482
3483 /*
3484 * Activate a device. This is called from dasd_{eckd,fba}_probe() when either
3485 * the device is detected for the first time and is supposed to be used
3486 * or the user has started activation through sysfs.
3487 */
dasd_generic_set_online(struct ccw_device * cdev,struct dasd_discipline * base_discipline)3488 int dasd_generic_set_online(struct ccw_device *cdev,
3489 struct dasd_discipline *base_discipline)
3490 {
3491 struct dasd_discipline *discipline;
3492 struct dasd_device *device;
3493 int rc;
3494
3495 /* first online clears initial online feature flag */
3496 dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
3497 device = dasd_create_device(cdev);
3498 if (IS_ERR(device))
3499 return PTR_ERR(device);
3500
3501 discipline = base_discipline;
3502 if (device->features & DASD_FEATURE_USEDIAG) {
3503 if (!dasd_diag_discipline_pointer) {
3504 /* Try to load the required module. */
3505 rc = request_module(DASD_DIAG_MOD);
3506 if (rc) {
3507 pr_warn("%s Setting the DASD online failed "
3508 "because the required module %s "
3509 "could not be loaded (rc=%d)\n",
3510 dev_name(&cdev->dev), DASD_DIAG_MOD,
3511 rc);
3512 dasd_delete_device(device);
3513 return -ENODEV;
3514 }
3515 }
3516 /* Module init could have failed, so check again here after
3517 * request_module(). */
3518 if (!dasd_diag_discipline_pointer) {
3519 pr_warn("%s Setting the DASD online failed because of missing DIAG discipline\n",
3520 dev_name(&cdev->dev));
3521 dasd_delete_device(device);
3522 return -ENODEV;
3523 }
3524 discipline = dasd_diag_discipline_pointer;
3525 }
3526 if (!try_module_get(base_discipline->owner)) {
3527 dasd_delete_device(device);
3528 return -EINVAL;
3529 }
3530 if (!try_module_get(discipline->owner)) {
3531 module_put(base_discipline->owner);
3532 dasd_delete_device(device);
3533 return -EINVAL;
3534 }
3535 device->base_discipline = base_discipline;
3536 device->discipline = discipline;
3537
3538 /* check_device will allocate block device if necessary */
3539 rc = discipline->check_device(device);
3540 if (rc) {
3541 pr_warn("%s Setting the DASD online with discipline %s failed with rc=%i\n",
3542 dev_name(&cdev->dev), discipline->name, rc);
3543 module_put(discipline->owner);
3544 module_put(base_discipline->owner);
3545 dasd_delete_device(device);
3546 return rc;
3547 }
3548
3549 dasd_set_target_state(device, DASD_STATE_ONLINE);
3550 if (device->state <= DASD_STATE_KNOWN) {
3551 pr_warn("%s Setting the DASD online failed because of a missing discipline\n",
3552 dev_name(&cdev->dev));
3553 rc = -ENODEV;
3554 dasd_set_target_state(device, DASD_STATE_NEW);
3555 if (device->block)
3556 dasd_free_block(device->block);
3557 dasd_delete_device(device);
3558 } else
3559 pr_debug("dasd_generic device %s found\n",
3560 dev_name(&cdev->dev));
3561
3562 wait_event(dasd_init_waitq, _wait_for_device(device));
3563
3564 dasd_put_device(device);
3565 return rc;
3566 }
3567 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
3568
dasd_generic_set_offline(struct ccw_device * cdev)3569 int dasd_generic_set_offline(struct ccw_device *cdev)
3570 {
3571 struct dasd_device *device;
3572 struct dasd_block *block;
3573 int max_count, open_count, rc;
3574 unsigned long flags;
3575
3576 rc = 0;
3577 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3578 device = dasd_device_from_cdev_locked(cdev);
3579 if (IS_ERR(device)) {
3580 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3581 return PTR_ERR(device);
3582 }
3583
3584 /*
3585 * We must make sure that this device is currently not in use.
3586 * The open_count is increased for every opener, that includes
3587 * the blkdev_get in dasd_scan_partitions. We are only interested
3588 * in the other openers.
3589 */
3590 if (device->block) {
3591 max_count = device->block->bdev_handle ? 0 : -1;
3592 open_count = atomic_read(&device->block->open_count);
3593 if (open_count > max_count) {
3594 if (open_count > 0)
3595 pr_warn("%s: The DASD cannot be set offline with open count %i\n",
3596 dev_name(&cdev->dev), open_count);
3597 else
3598 pr_warn("%s: The DASD cannot be set offline while it is in use\n",
3599 dev_name(&cdev->dev));
3600 rc = -EBUSY;
3601 goto out_err;
3602 }
3603 }
3604
3605 /*
3606 * Test if the offline processing is already running and exit if so.
3607 * If a safe offline is being processed this could only be a normal
3608 * offline that should be able to overtake the safe offline and
3609 * cancel any I/O we do not want to wait for any longer
3610 */
3611 if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3612 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3613 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING,
3614 &device->flags);
3615 } else {
3616 rc = -EBUSY;
3617 goto out_err;
3618 }
3619 }
3620 set_bit(DASD_FLAG_OFFLINE, &device->flags);
3621
3622 /*
3623 * if safe_offline is called set safe_offline_running flag and
3624 * clear safe_offline so that a call to normal offline
3625 * can overrun safe_offline processing
3626 */
3627 if (test_and_clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags) &&
3628 !test_and_set_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3629 /* need to unlock here to wait for outstanding I/O */
3630 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3631 /*
3632 * If we want to set the device safe offline all IO operations
3633 * should be finished before continuing the offline process
3634 * so sync bdev first and then wait for our queues to become
3635 * empty
3636 */
3637 if (device->block && device->block->bdev_handle)
3638 bdev_mark_dead(device->block->bdev_handle->bdev, false);
3639 dasd_schedule_device_bh(device);
3640 rc = wait_event_interruptible(shutdown_waitq,
3641 _wait_for_empty_queues(device));
3642 if (rc != 0)
3643 goto interrupted;
3644
3645 /*
3646 * check if a normal offline process overtook the offline
3647 * processing in this case simply do nothing beside returning
3648 * that we got interrupted
3649 * otherwise mark safe offline as not running any longer and
3650 * continue with normal offline
3651 */
3652 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3653 if (!test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3654 rc = -ERESTARTSYS;
3655 goto out_err;
3656 }
3657 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
3658 }
3659 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3660
3661 dasd_set_target_state(device, DASD_STATE_NEW);
3662 /* dasd_delete_device destroys the device reference. */
3663 block = device->block;
3664 dasd_delete_device(device);
3665 /*
3666 * life cycle of block is bound to device, so delete it after
3667 * device was safely removed
3668 */
3669 if (block)
3670 dasd_free_block(block);
3671
3672 return 0;
3673
3674 interrupted:
3675 /* interrupted by signal */
3676 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3677 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
3678 clear_bit(DASD_FLAG_OFFLINE, &device->flags);
3679 out_err:
3680 dasd_put_device(device);
3681 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3682 return rc;
3683 }
3684 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
3685
dasd_generic_last_path_gone(struct dasd_device * device)3686 int dasd_generic_last_path_gone(struct dasd_device *device)
3687 {
3688 struct dasd_ccw_req *cqr;
3689
3690 dev_warn(&device->cdev->dev, "No operational channel path is left "
3691 "for the device\n");
3692 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone");
3693 /* First call extended error reporting and check for autoquiesce. */
3694 dasd_handle_autoquiesce(device, NULL, DASD_EER_NOPATH);
3695
3696 if (device->state < DASD_STATE_BASIC)
3697 return 0;
3698 /* Device is active. We want to keep it. */
3699 list_for_each_entry(cqr, &device->ccw_queue, devlist)
3700 if ((cqr->status == DASD_CQR_IN_IO) ||
3701 (cqr->status == DASD_CQR_CLEAR_PENDING)) {
3702 cqr->status = DASD_CQR_QUEUED;
3703 cqr->retries++;
3704 }
3705 dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT);
3706 dasd_device_clear_timer(device);
3707 dasd_schedule_device_bh(device);
3708 return 1;
3709 }
3710 EXPORT_SYMBOL_GPL(dasd_generic_last_path_gone);
3711
dasd_generic_path_operational(struct dasd_device * device)3712 int dasd_generic_path_operational(struct dasd_device *device)
3713 {
3714 dev_info(&device->cdev->dev, "A channel path to the device has become "
3715 "operational\n");
3716 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational");
3717 dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT);
3718 dasd_schedule_device_bh(device);
3719 if (device->block) {
3720 dasd_schedule_block_bh(device->block);
3721 if (device->block->gdp)
3722 blk_mq_run_hw_queues(device->block->gdp->queue, true);
3723 }
3724
3725 if (!device->stopped)
3726 wake_up(&generic_waitq);
3727
3728 return 1;
3729 }
3730 EXPORT_SYMBOL_GPL(dasd_generic_path_operational);
3731
dasd_generic_notify(struct ccw_device * cdev,int event)3732 int dasd_generic_notify(struct ccw_device *cdev, int event)
3733 {
3734 struct dasd_device *device;
3735 int ret;
3736
3737 device = dasd_device_from_cdev_locked(cdev);
3738 if (IS_ERR(device))
3739 return 0;
3740 ret = 0;
3741 switch (event) {
3742 case CIO_GONE:
3743 case CIO_BOXED:
3744 case CIO_NO_PATH:
3745 dasd_path_no_path(device);
3746 ret = dasd_generic_last_path_gone(device);
3747 break;
3748 case CIO_OPER:
3749 ret = 1;
3750 if (dasd_path_get_opm(device))
3751 ret = dasd_generic_path_operational(device);
3752 break;
3753 }
3754 dasd_put_device(device);
3755 return ret;
3756 }
3757 EXPORT_SYMBOL_GPL(dasd_generic_notify);
3758
dasd_generic_path_event(struct ccw_device * cdev,int * path_event)3759 void dasd_generic_path_event(struct ccw_device *cdev, int *path_event)
3760 {
3761 struct dasd_device *device;
3762 int chp, oldopm, hpfpm, ifccpm;
3763
3764 device = dasd_device_from_cdev_locked(cdev);
3765 if (IS_ERR(device))
3766 return;
3767
3768 oldopm = dasd_path_get_opm(device);
3769 for (chp = 0; chp < 8; chp++) {
3770 if (path_event[chp] & PE_PATH_GONE) {
3771 dasd_path_notoper(device, chp);
3772 }
3773 if (path_event[chp] & PE_PATH_AVAILABLE) {
3774 dasd_path_available(device, chp);
3775 dasd_schedule_device_bh(device);
3776 }
3777 if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) {
3778 if (!dasd_path_is_operational(device, chp) &&
3779 !dasd_path_need_verify(device, chp)) {
3780 /*
3781 * we can not establish a pathgroup on an
3782 * unavailable path, so trigger a path
3783 * verification first
3784 */
3785 dasd_path_available(device, chp);
3786 dasd_schedule_device_bh(device);
3787 }
3788 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
3789 "Pathgroup re-established\n");
3790 if (device->discipline->kick_validate)
3791 device->discipline->kick_validate(device);
3792 }
3793 if (path_event[chp] & PE_PATH_FCES_EVENT) {
3794 dasd_path_fcsec_update(device, chp);
3795 dasd_schedule_device_bh(device);
3796 }
3797 }
3798 hpfpm = dasd_path_get_hpfpm(device);
3799 ifccpm = dasd_path_get_ifccpm(device);
3800 if (!dasd_path_get_opm(device) && hpfpm) {
3801 /*
3802 * device has no operational paths but at least one path is
3803 * disabled due to HPF errors
3804 * disable HPF at all and use the path(s) again
3805 */
3806 if (device->discipline->disable_hpf)
3807 device->discipline->disable_hpf(device);
3808 dasd_device_set_stop_bits(device, DASD_STOPPED_NOT_ACC);
3809 dasd_path_set_tbvpm(device, hpfpm);
3810 dasd_schedule_device_bh(device);
3811 dasd_schedule_requeue(device);
3812 } else if (!dasd_path_get_opm(device) && ifccpm) {
3813 /*
3814 * device has no operational paths but at least one path is
3815 * disabled due to IFCC errors
3816 * trigger path verification on paths with IFCC errors
3817 */
3818 dasd_path_set_tbvpm(device, ifccpm);
3819 dasd_schedule_device_bh(device);
3820 }
3821 if (oldopm && !dasd_path_get_opm(device) && !hpfpm && !ifccpm) {
3822 dev_warn(&device->cdev->dev,
3823 "No verified channel paths remain for the device\n");
3824 DBF_DEV_EVENT(DBF_WARNING, device,
3825 "%s", "last verified path gone");
3826 /* First call extended error reporting and check for autoquiesce. */
3827 dasd_handle_autoquiesce(device, NULL, DASD_EER_NOPATH);
3828 dasd_device_set_stop_bits(device,
3829 DASD_STOPPED_DC_WAIT);
3830 }
3831 dasd_put_device(device);
3832 }
3833 EXPORT_SYMBOL_GPL(dasd_generic_path_event);
3834
dasd_generic_verify_path(struct dasd_device * device,__u8 lpm)3835 int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm)
3836 {
3837 if (!dasd_path_get_opm(device) && lpm) {
3838 dasd_path_set_opm(device, lpm);
3839 dasd_generic_path_operational(device);
3840 } else
3841 dasd_path_add_opm(device, lpm);
3842 return 0;
3843 }
3844 EXPORT_SYMBOL_GPL(dasd_generic_verify_path);
3845
dasd_generic_space_exhaust(struct dasd_device * device,struct dasd_ccw_req * cqr)3846 void dasd_generic_space_exhaust(struct dasd_device *device,
3847 struct dasd_ccw_req *cqr)
3848 {
3849 /* First call extended error reporting and check for autoquiesce. */
3850 dasd_handle_autoquiesce(device, NULL, DASD_EER_NOSPC);
3851
3852 if (device->state < DASD_STATE_BASIC)
3853 return;
3854
3855 if (cqr->status == DASD_CQR_IN_IO ||
3856 cqr->status == DASD_CQR_CLEAR_PENDING) {
3857 cqr->status = DASD_CQR_QUEUED;
3858 cqr->retries++;
3859 }
3860 dasd_device_set_stop_bits(device, DASD_STOPPED_NOSPC);
3861 dasd_device_clear_timer(device);
3862 dasd_schedule_device_bh(device);
3863 }
3864 EXPORT_SYMBOL_GPL(dasd_generic_space_exhaust);
3865
dasd_generic_space_avail(struct dasd_device * device)3866 void dasd_generic_space_avail(struct dasd_device *device)
3867 {
3868 dev_info(&device->cdev->dev, "Extent pool space is available\n");
3869 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "space available");
3870
3871 dasd_device_remove_stop_bits(device, DASD_STOPPED_NOSPC);
3872 dasd_schedule_device_bh(device);
3873
3874 if (device->block) {
3875 dasd_schedule_block_bh(device->block);
3876 if (device->block->gdp)
3877 blk_mq_run_hw_queues(device->block->gdp->queue, true);
3878 }
3879 if (!device->stopped)
3880 wake_up(&generic_waitq);
3881 }
3882 EXPORT_SYMBOL_GPL(dasd_generic_space_avail);
3883
3884 /*
3885 * clear active requests and requeue them to block layer if possible
3886 */
dasd_generic_requeue_all_requests(struct dasd_device * device)3887 int dasd_generic_requeue_all_requests(struct dasd_device *device)
3888 {
3889 struct dasd_block *block = device->block;
3890 struct list_head requeue_queue;
3891 struct dasd_ccw_req *cqr, *n;
3892 int rc;
3893
3894 if (!block)
3895 return 0;
3896
3897 INIT_LIST_HEAD(&requeue_queue);
3898 rc = _dasd_requests_to_flushqueue(block, &requeue_queue);
3899
3900 /* Now call the callback function of flushed requests */
3901 restart_cb:
3902 list_for_each_entry_safe(cqr, n, &requeue_queue, blocklist) {
3903 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
3904 /* Process finished ERP request. */
3905 if (cqr->refers) {
3906 spin_lock_bh(&block->queue_lock);
3907 __dasd_process_erp(block->base, cqr);
3908 spin_unlock_bh(&block->queue_lock);
3909 /* restart list_for_xx loop since dasd_process_erp
3910 * might remove multiple elements
3911 */
3912 goto restart_cb;
3913 }
3914 _dasd_requeue_request(cqr);
3915 list_del_init(&cqr->blocklist);
3916 cqr->block->base->discipline->free_cp(
3917 cqr, (struct request *) cqr->callback_data);
3918 }
3919 dasd_schedule_device_bh(device);
3920 return rc;
3921 }
3922 EXPORT_SYMBOL_GPL(dasd_generic_requeue_all_requests);
3923
do_requeue_requests(struct work_struct * work)3924 static void do_requeue_requests(struct work_struct *work)
3925 {
3926 struct dasd_device *device = container_of(work, struct dasd_device,
3927 requeue_requests);
3928 dasd_generic_requeue_all_requests(device);
3929 dasd_device_remove_stop_bits(device, DASD_STOPPED_NOT_ACC);
3930 if (device->block)
3931 dasd_schedule_block_bh(device->block);
3932 dasd_put_device(device);
3933 }
3934
dasd_schedule_requeue(struct dasd_device * device)3935 void dasd_schedule_requeue(struct dasd_device *device)
3936 {
3937 dasd_get_device(device);
3938 /* queue call to dasd_reload_device to the kernel event daemon. */
3939 if (!schedule_work(&device->requeue_requests))
3940 dasd_put_device(device);
3941 }
3942 EXPORT_SYMBOL(dasd_schedule_requeue);
3943
dasd_handle_autoquiesce(struct dasd_device * device,struct dasd_ccw_req * cqr,unsigned int reason)3944 static int dasd_handle_autoquiesce(struct dasd_device *device,
3945 struct dasd_ccw_req *cqr,
3946 unsigned int reason)
3947 {
3948 /* in any case write eer message with reason */
3949 if (dasd_eer_enabled(device))
3950 dasd_eer_write(device, cqr, reason);
3951
3952 if (!test_bit(reason, &device->aq_mask))
3953 return 0;
3954
3955 /* notify eer about autoquiesce */
3956 if (dasd_eer_enabled(device))
3957 dasd_eer_write(device, NULL, DASD_EER_AUTOQUIESCE);
3958
3959 pr_info("%s: The DASD has been put in the quiesce state\n",
3960 dev_name(&device->cdev->dev));
3961 dasd_device_set_stop_bits(device, DASD_STOPPED_QUIESCE);
3962
3963 if (device->features & DASD_FEATURE_REQUEUEQUIESCE)
3964 dasd_schedule_requeue(device);
3965
3966 return 1;
3967 }
3968
dasd_generic_build_rdc(struct dasd_device * device,int rdc_buffer_size,int magic)3969 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
3970 int rdc_buffer_size,
3971 int magic)
3972 {
3973 struct dasd_ccw_req *cqr;
3974 struct ccw1 *ccw;
3975
3976 cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device,
3977 NULL);
3978
3979 if (IS_ERR(cqr)) {
3980 /* internal error 13 - Allocating the RDC request failed*/
3981 dev_err(&device->cdev->dev,
3982 "An error occurred in the DASD device driver, "
3983 "reason=%s\n", "13");
3984 return cqr;
3985 }
3986
3987 ccw = cqr->cpaddr;
3988 ccw->cmd_code = CCW_CMD_RDC;
3989 ccw->cda = (__u32)virt_to_phys(cqr->data);
3990 ccw->flags = 0;
3991 ccw->count = rdc_buffer_size;
3992 cqr->startdev = device;
3993 cqr->memdev = device;
3994 cqr->expires = 10*HZ;
3995 cqr->retries = 256;
3996 cqr->buildclk = get_tod_clock();
3997 cqr->status = DASD_CQR_FILLED;
3998 return cqr;
3999 }
4000
4001
dasd_generic_read_dev_chars(struct dasd_device * device,int magic,void * rdc_buffer,int rdc_buffer_size)4002 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
4003 void *rdc_buffer, int rdc_buffer_size)
4004 {
4005 int ret;
4006 struct dasd_ccw_req *cqr;
4007
4008 cqr = dasd_generic_build_rdc(device, rdc_buffer_size, magic);
4009 if (IS_ERR(cqr))
4010 return PTR_ERR(cqr);
4011
4012 ret = dasd_sleep_on(cqr);
4013 if (ret == 0)
4014 memcpy(rdc_buffer, cqr->data, rdc_buffer_size);
4015 dasd_sfree_request(cqr, cqr->memdev);
4016 return ret;
4017 }
4018 EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
4019
4020 /*
4021 * In command mode and transport mode we need to look for sense
4022 * data in different places. The sense data itself is allways
4023 * an array of 32 bytes, so we can unify the sense data access
4024 * for both modes.
4025 */
dasd_get_sense(struct irb * irb)4026 char *dasd_get_sense(struct irb *irb)
4027 {
4028 struct tsb *tsb = NULL;
4029 char *sense = NULL;
4030
4031 if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
4032 if (irb->scsw.tm.tcw)
4033 tsb = tcw_get_tsb(phys_to_virt(irb->scsw.tm.tcw));
4034 if (tsb && tsb->length == 64 && tsb->flags)
4035 switch (tsb->flags & 0x07) {
4036 case 1: /* tsa_iostat */
4037 sense = tsb->tsa.iostat.sense;
4038 break;
4039 case 2: /* tsa_ddpc */
4040 sense = tsb->tsa.ddpc.sense;
4041 break;
4042 default:
4043 /* currently we don't use interrogate data */
4044 break;
4045 }
4046 } else if (irb->esw.esw0.erw.cons) {
4047 sense = irb->ecw;
4048 }
4049 return sense;
4050 }
4051 EXPORT_SYMBOL_GPL(dasd_get_sense);
4052
dasd_generic_shutdown(struct ccw_device * cdev)4053 void dasd_generic_shutdown(struct ccw_device *cdev)
4054 {
4055 struct dasd_device *device;
4056
4057 device = dasd_device_from_cdev(cdev);
4058 if (IS_ERR(device))
4059 return;
4060
4061 if (device->block)
4062 dasd_schedule_block_bh(device->block);
4063
4064 dasd_schedule_device_bh(device);
4065
4066 wait_event(shutdown_waitq, _wait_for_empty_queues(device));
4067 }
4068 EXPORT_SYMBOL_GPL(dasd_generic_shutdown);
4069
dasd_init(void)4070 static int __init dasd_init(void)
4071 {
4072 int rc;
4073
4074 init_waitqueue_head(&dasd_init_waitq);
4075 init_waitqueue_head(&dasd_flush_wq);
4076 init_waitqueue_head(&generic_waitq);
4077 init_waitqueue_head(&shutdown_waitq);
4078
4079 /* register 'common' DASD debug area, used for all DBF_XXX calls */
4080 dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
4081 if (dasd_debug_area == NULL) {
4082 rc = -ENOMEM;
4083 goto failed;
4084 }
4085 debug_register_view(dasd_debug_area, &debug_sprintf_view);
4086 debug_set_level(dasd_debug_area, DBF_WARNING);
4087
4088 DBF_EVENT(DBF_EMERG, "%s", "debug area created");
4089
4090 dasd_diag_discipline_pointer = NULL;
4091
4092 dasd_statistics_createroot();
4093
4094 rc = dasd_devmap_init();
4095 if (rc)
4096 goto failed;
4097 rc = dasd_gendisk_init();
4098 if (rc)
4099 goto failed;
4100 rc = dasd_parse();
4101 if (rc)
4102 goto failed;
4103 rc = dasd_eer_init();
4104 if (rc)
4105 goto failed;
4106 #ifdef CONFIG_PROC_FS
4107 rc = dasd_proc_init();
4108 if (rc)
4109 goto failed;
4110 #endif
4111
4112 return 0;
4113 failed:
4114 pr_info("The DASD device driver could not be initialized\n");
4115 dasd_exit();
4116 return rc;
4117 }
4118
4119 module_init(dasd_init);
4120 module_exit(dasd_exit);
4121