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xtensa: support DMA buffers in high memory
[cris-mirror.git] / drivers / s390 / block / dasd.c
bloba7c15f0085e2999787a391327db0f6398d4c2cf0
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_SUPPORTED_DEVICE("dasd");
58 MODULE_LICENSE("GPL");
59
60 /*
61 * SECTION: prototypes for static functions of dasd.c
62 */
63 static int dasd_alloc_queue(struct dasd_block *);
64 static void dasd_setup_queue(struct dasd_block *);
65 static void dasd_free_queue(struct dasd_block *);
66 static int dasd_flush_block_queue(struct dasd_block *);
67 static void dasd_device_tasklet(struct dasd_device *);
68 static void dasd_block_tasklet(struct dasd_block *);
69 static void do_kick_device(struct work_struct *);
70 static void do_restore_device(struct work_struct *);
71 static void do_reload_device(struct work_struct *);
72 static void do_requeue_requests(struct work_struct *);
73 static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
74 static void dasd_device_timeout(struct timer_list *);
75 static void dasd_block_timeout(struct timer_list *);
76 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
77 static void dasd_profile_init(struct dasd_profile *, struct dentry *);
78 static void dasd_profile_exit(struct dasd_profile *);
79 static void dasd_hosts_init(struct dentry *, struct dasd_device *);
80 static void dasd_hosts_exit(struct dasd_device *);
81
82 /*
83 * SECTION: Operations on the device structure.
84 */
85 static wait_queue_head_t dasd_init_waitq;
86 static wait_queue_head_t dasd_flush_wq;
87 static wait_queue_head_t generic_waitq;
88 static wait_queue_head_t shutdown_waitq;
89
90 /*
91 * Allocate memory for a new device structure.
92 */
93 struct dasd_device *dasd_alloc_device(void)
94 {
95 struct dasd_device *device;
96
97 device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
98 if (!device)
99 return ERR_PTR(-ENOMEM);
100
101 /* Get two pages for normal block device operations. */
102 device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
103 if (!device->ccw_mem) {
104 kfree(device);
105 return ERR_PTR(-ENOMEM);
106 }
107 /* Get one page for error recovery. */
108 device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
109 if (!device->erp_mem) {
110 free_pages((unsigned long) device->ccw_mem, 1);
111 kfree(device);
112 return ERR_PTR(-ENOMEM);
113 }
114
115 dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
116 dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
117 spin_lock_init(&device->mem_lock);
118 atomic_set(&device->tasklet_scheduled, 0);
119 tasklet_init(&device->tasklet,
120 (void (*)(unsigned long)) dasd_device_tasklet,
121 (unsigned long) device);
122 INIT_LIST_HEAD(&device->ccw_queue);
123 timer_setup(&device->timer, dasd_device_timeout, 0);
124 INIT_WORK(&device->kick_work, do_kick_device);
125 INIT_WORK(&device->restore_device, do_restore_device);
126 INIT_WORK(&device->reload_device, do_reload_device);
127 INIT_WORK(&device->requeue_requests, do_requeue_requests);
128 device->state = DASD_STATE_NEW;
129 device->target = DASD_STATE_NEW;
130 mutex_init(&device->state_mutex);
131 spin_lock_init(&device->profile.lock);
132 return device;
133 }
134
135 /*
136 * Free memory of a device structure.
137 */
138 void dasd_free_device(struct dasd_device *device)
139 {
140 kfree(device->private);
141 free_page((unsigned long) device->erp_mem);
142 free_pages((unsigned long) device->ccw_mem, 1);
143 kfree(device);
144 }
145
146 /*
147 * Allocate memory for a new device structure.
148 */
149 struct dasd_block *dasd_alloc_block(void)
150 {
151 struct dasd_block *block;
152
153 block = kzalloc(sizeof(*block), GFP_ATOMIC);
154 if (!block)
155 return ERR_PTR(-ENOMEM);
156 /* open_count = 0 means device online but not in use */
157 atomic_set(&block->open_count, -1);
158
159 atomic_set(&block->tasklet_scheduled, 0);
160 tasklet_init(&block->tasklet,
161 (void (*)(unsigned long)) dasd_block_tasklet,
162 (unsigned long) block);
163 INIT_LIST_HEAD(&block->ccw_queue);
164 spin_lock_init(&block->queue_lock);
165 timer_setup(&block->timer, dasd_block_timeout, 0);
166 spin_lock_init(&block->profile.lock);
167
168 return block;
169 }
170 EXPORT_SYMBOL_GPL(dasd_alloc_block);
171
172 /*
173 * Free memory of a device structure.
174 */
175 void dasd_free_block(struct dasd_block *block)
176 {
177 kfree(block);
178 }
179 EXPORT_SYMBOL_GPL(dasd_free_block);
180
181 /*
182 * Make a new device known to the system.
183 */
184 static int dasd_state_new_to_known(struct dasd_device *device)
185 {
186 int rc;
187
188 /*
189 * As long as the device is not in state DASD_STATE_NEW we want to
190 * keep the reference count > 0.
191 */
192 dasd_get_device(device);
193
194 if (device->block) {
195 rc = dasd_alloc_queue(device->block);
196 if (rc) {
197 dasd_put_device(device);
198 return rc;
199 }
200 }
201 device->state = DASD_STATE_KNOWN;
202 return 0;
203 }
204
205 /*
206 * Let the system forget about a device.
207 */
208 static int dasd_state_known_to_new(struct dasd_device *device)
209 {
210 /* Disable extended error reporting for this device. */
211 dasd_eer_disable(device);
212 device->state = DASD_STATE_NEW;
213
214 if (device->block)
215 dasd_free_queue(device->block);
216
217 /* Give up reference we took in dasd_state_new_to_known. */
218 dasd_put_device(device);
219 return 0;
220 }
221
222 static struct dentry *dasd_debugfs_setup(const char *name,
223 struct dentry *base_dentry)
224 {
225 struct dentry *pde;
226
227 if (!base_dentry)
228 return NULL;
229 pde = debugfs_create_dir(name, base_dentry);
230 if (!pde || IS_ERR(pde))
231 return NULL;
232 return pde;
233 }
234
235 /*
236 * Request the irq line for the device.
237 */
238 static int dasd_state_known_to_basic(struct dasd_device *device)
239 {
240 struct dasd_block *block = device->block;
241 int rc = 0;
242
243 /* Allocate and register gendisk structure. */
244 if (block) {
245 rc = dasd_gendisk_alloc(block);
246 if (rc)
247 return rc;
248 block->debugfs_dentry =
249 dasd_debugfs_setup(block->gdp->disk_name,
250 dasd_debugfs_root_entry);
251 dasd_profile_init(&block->profile, block->debugfs_dentry);
252 if (dasd_global_profile_level == DASD_PROFILE_ON)
253 dasd_profile_on(&device->block->profile);
254 }
255 device->debugfs_dentry =
256 dasd_debugfs_setup(dev_name(&device->cdev->dev),
257 dasd_debugfs_root_entry);
258 dasd_profile_init(&device->profile, device->debugfs_dentry);
259 dasd_hosts_init(device->debugfs_dentry, device);
260
261 /* register 'device' debug area, used for all DBF_DEV_XXX calls */
262 device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
263 8 * sizeof(long));
264 debug_register_view(device->debug_area, &debug_sprintf_view);
265 debug_set_level(device->debug_area, DBF_WARNING);
266 DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
267
268 device->state = DASD_STATE_BASIC;
269
270 return rc;
271 }
272
273 /*
274 * Release the irq line for the device. Terminate any running i/o.
275 */
276 static int dasd_state_basic_to_known(struct dasd_device *device)
277 {
278 int rc;
279
280 if (device->discipline->basic_to_known) {
281 rc = device->discipline->basic_to_known(device);
282 if (rc)
283 return rc;
284 }
285
286 if (device->block) {
287 dasd_profile_exit(&device->block->profile);
288 debugfs_remove(device->block->debugfs_dentry);
289 dasd_gendisk_free(device->block);
290 dasd_block_clear_timer(device->block);
291 }
292 rc = dasd_flush_device_queue(device);
293 if (rc)
294 return rc;
295 dasd_device_clear_timer(device);
296 dasd_profile_exit(&device->profile);
297 dasd_hosts_exit(device);
298 debugfs_remove(device->debugfs_dentry);
299 DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
300 if (device->debug_area != NULL) {
301 debug_unregister(device->debug_area);
302 device->debug_area = NULL;
303 }
304 device->state = DASD_STATE_KNOWN;
305 return 0;
306 }
307
308 /*
309 * Do the initial analysis. The do_analysis function may return
310 * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
311 * until the discipline decides to continue the startup sequence
312 * by calling the function dasd_change_state. The eckd disciplines
313 * uses this to start a ccw that detects the format. The completion
314 * interrupt for this detection ccw uses the kernel event daemon to
315 * trigger the call to dasd_change_state. All this is done in the
316 * discipline code, see dasd_eckd.c.
317 * After the analysis ccw is done (do_analysis returned 0) the block
318 * device is setup.
319 * In case the analysis returns an error, the device setup is stopped
320 * (a fake disk was already added to allow formatting).
321 */
322 static int dasd_state_basic_to_ready(struct dasd_device *device)
323 {
324 int rc;
325 struct dasd_block *block;
326 struct gendisk *disk;
327
328 rc = 0;
329 block = device->block;
330 /* make disk known with correct capacity */
331 if (block) {
332 if (block->base->discipline->do_analysis != NULL)
333 rc = block->base->discipline->do_analysis(block);
334 if (rc) {
335 if (rc != -EAGAIN) {
336 device->state = DASD_STATE_UNFMT;
337 disk = device->block->gdp;
338 kobject_uevent(&disk_to_dev(disk)->kobj,
339 KOBJ_CHANGE);
340 goto out;
341 }
342 return rc;
343 }
344 dasd_setup_queue(block);
345 set_capacity(block->gdp,
346 block->blocks << block->s2b_shift);
347 device->state = DASD_STATE_READY;
348 rc = dasd_scan_partitions(block);
349 if (rc) {
350 device->state = DASD_STATE_BASIC;
351 return rc;
352 }
353 } else {
354 device->state = DASD_STATE_READY;
355 }
356 out:
357 if (device->discipline->basic_to_ready)
358 rc = device->discipline->basic_to_ready(device);
359 return rc;
360 }
361
362 static inline
363 int _wait_for_empty_queues(struct dasd_device *device)
364 {
365 if (device->block)
366 return list_empty(&device->ccw_queue) &&
367 list_empty(&device->block->ccw_queue);
368 else
369 return list_empty(&device->ccw_queue);
370 }
371
372 /*
373 * Remove device from block device layer. Destroy dirty buffers.
374 * Forget format information. Check if the target level is basic
375 * and if it is create fake disk for formatting.
376 */
377 static int dasd_state_ready_to_basic(struct dasd_device *device)
378 {
379 int rc;
380
381 device->state = DASD_STATE_BASIC;
382 if (device->block) {
383 struct dasd_block *block = device->block;
384 rc = dasd_flush_block_queue(block);
385 if (rc) {
386 device->state = DASD_STATE_READY;
387 return rc;
388 }
389 dasd_destroy_partitions(block);
390 block->blocks = 0;
391 block->bp_block = 0;
392 block->s2b_shift = 0;
393 }
394 return 0;
395 }
396
397 /*
398 * Back to basic.
399 */
400 static int dasd_state_unfmt_to_basic(struct dasd_device *device)
401 {
402 device->state = DASD_STATE_BASIC;
403 return 0;
404 }
405
406 /*
407 * Make the device online and schedule the bottom half to start
408 * the requeueing of requests from the linux request queue to the
409 * ccw queue.
410 */
411 static int
412 dasd_state_ready_to_online(struct dasd_device * device)
413 {
414 struct gendisk *disk;
415 struct disk_part_iter piter;
416 struct hd_struct *part;
417
418 device->state = DASD_STATE_ONLINE;
419 if (device->block) {
420 dasd_schedule_block_bh(device->block);
421 if ((device->features & DASD_FEATURE_USERAW)) {
422 disk = device->block->gdp;
423 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
424 return 0;
425 }
426 disk = device->block->bdev->bd_disk;
427 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
428 while ((part = disk_part_iter_next(&piter)))
429 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
430 disk_part_iter_exit(&piter);
431 }
432 return 0;
433 }
434
435 /*
436 * Stop the requeueing of requests again.
437 */
438 static int dasd_state_online_to_ready(struct dasd_device *device)
439 {
440 int rc;
441 struct gendisk *disk;
442 struct disk_part_iter piter;
443 struct hd_struct *part;
444
445 if (device->discipline->online_to_ready) {
446 rc = device->discipline->online_to_ready(device);
447 if (rc)
448 return rc;
449 }
450
451 device->state = DASD_STATE_READY;
452 if (device->block && !(device->features & DASD_FEATURE_USERAW)) {
453 disk = device->block->bdev->bd_disk;
454 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
455 while ((part = disk_part_iter_next(&piter)))
456 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
457 disk_part_iter_exit(&piter);
458 }
459 return 0;
460 }
461
462 /*
463 * Device startup state changes.
464 */
465 static int dasd_increase_state(struct dasd_device *device)
466 {
467 int rc;
468
469 rc = 0;
470 if (device->state == DASD_STATE_NEW &&
471 device->target >= DASD_STATE_KNOWN)
472 rc = dasd_state_new_to_known(device);
473
474 if (!rc &&
475 device->state == DASD_STATE_KNOWN &&
476 device->target >= DASD_STATE_BASIC)
477 rc = dasd_state_known_to_basic(device);
478
479 if (!rc &&
480 device->state == DASD_STATE_BASIC &&
481 device->target >= DASD_STATE_READY)
482 rc = dasd_state_basic_to_ready(device);
483
484 if (!rc &&
485 device->state == DASD_STATE_UNFMT &&
486 device->target > DASD_STATE_UNFMT)
487 rc = -EPERM;
488
489 if (!rc &&
490 device->state == DASD_STATE_READY &&
491 device->target >= DASD_STATE_ONLINE)
492 rc = dasd_state_ready_to_online(device);
493
494 return rc;
495 }
496
497 /*
498 * Device shutdown state changes.
499 */
500 static int dasd_decrease_state(struct dasd_device *device)
501 {
502 int rc;
503
504 rc = 0;
505 if (device->state == DASD_STATE_ONLINE &&
506 device->target <= DASD_STATE_READY)
507 rc = dasd_state_online_to_ready(device);
508
509 if (!rc &&
510 device->state == DASD_STATE_READY &&
511 device->target <= DASD_STATE_BASIC)
512 rc = dasd_state_ready_to_basic(device);
513
514 if (!rc &&
515 device->state == DASD_STATE_UNFMT &&
516 device->target <= DASD_STATE_BASIC)
517 rc = dasd_state_unfmt_to_basic(device);
518
519 if (!rc &&
520 device->state == DASD_STATE_BASIC &&
521 device->target <= DASD_STATE_KNOWN)
522 rc = dasd_state_basic_to_known(device);
523
524 if (!rc &&
525 device->state == DASD_STATE_KNOWN &&
526 device->target <= DASD_STATE_NEW)
527 rc = dasd_state_known_to_new(device);
528
529 return rc;
530 }
531
532 /*
533 * This is the main startup/shutdown routine.
534 */
535 static void dasd_change_state(struct dasd_device *device)
536 {
537 int rc;
538
539 if (device->state == device->target)
540 /* Already where we want to go today... */
541 return;
542 if (device->state < device->target)
543 rc = dasd_increase_state(device);
544 else
545 rc = dasd_decrease_state(device);
546 if (rc == -EAGAIN)
547 return;
548 if (rc)
549 device->target = device->state;
550
551 /* let user-space know that the device status changed */
552 kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
553
554 if (device->state == device->target)
555 wake_up(&dasd_init_waitq);
556 }
557
558 /*
559 * Kick starter for devices that did not complete the startup/shutdown
560 * procedure or were sleeping because of a pending state.
561 * dasd_kick_device will schedule a call do do_kick_device to the kernel
562 * event daemon.
563 */
564 static void do_kick_device(struct work_struct *work)
565 {
566 struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
567 mutex_lock(&device->state_mutex);
568 dasd_change_state(device);
569 mutex_unlock(&device->state_mutex);
570 dasd_schedule_device_bh(device);
571 dasd_put_device(device);
572 }
573
574 void dasd_kick_device(struct dasd_device *device)
575 {
576 dasd_get_device(device);
577 /* queue call to dasd_kick_device to the kernel event daemon. */
578 if (!schedule_work(&device->kick_work))
579 dasd_put_device(device);
580 }
581 EXPORT_SYMBOL(dasd_kick_device);
582
583 /*
584 * dasd_reload_device will schedule a call do do_reload_device to the kernel
585 * event daemon.
586 */
587 static void do_reload_device(struct work_struct *work)
588 {
589 struct dasd_device *device = container_of(work, struct dasd_device,
590 reload_device);
591 device->discipline->reload(device);
592 dasd_put_device(device);
593 }
594
595 void dasd_reload_device(struct dasd_device *device)
596 {
597 dasd_get_device(device);
598 /* queue call to dasd_reload_device to the kernel event daemon. */
599 if (!schedule_work(&device->reload_device))
600 dasd_put_device(device);
601 }
602 EXPORT_SYMBOL(dasd_reload_device);
603
604 /*
605 * dasd_restore_device will schedule a call do do_restore_device to the kernel
606 * event daemon.
607 */
608 static void do_restore_device(struct work_struct *work)
609 {
610 struct dasd_device *device = container_of(work, struct dasd_device,
611 restore_device);
612 device->cdev->drv->restore(device->cdev);
613 dasd_put_device(device);
614 }
615
616 void dasd_restore_device(struct dasd_device *device)
617 {
618 dasd_get_device(device);
619 /* queue call to dasd_restore_device to the kernel event daemon. */
620 if (!schedule_work(&device->restore_device))
621 dasd_put_device(device);
622 }
623
624 /*
625 * Set the target state for a device and starts the state change.
626 */
627 void dasd_set_target_state(struct dasd_device *device, int target)
628 {
629 dasd_get_device(device);
630 mutex_lock(&device->state_mutex);
631 /* If we are in probeonly mode stop at DASD_STATE_READY. */
632 if (dasd_probeonly && target > DASD_STATE_READY)
633 target = DASD_STATE_READY;
634 if (device->target != target) {
635 if (device->state == target)
636 wake_up(&dasd_init_waitq);
637 device->target = target;
638 }
639 if (device->state != device->target)
640 dasd_change_state(device);
641 mutex_unlock(&device->state_mutex);
642 dasd_put_device(device);
643 }
644 EXPORT_SYMBOL(dasd_set_target_state);
645
646 /*
647 * Enable devices with device numbers in [from..to].
648 */
649 static inline int _wait_for_device(struct dasd_device *device)
650 {
651 return (device->state == device->target);
652 }
653
654 void dasd_enable_device(struct dasd_device *device)
655 {
656 dasd_set_target_state(device, DASD_STATE_ONLINE);
657 if (device->state <= DASD_STATE_KNOWN)
658 /* No discipline for device found. */
659 dasd_set_target_state(device, DASD_STATE_NEW);
660 /* Now wait for the devices to come up. */
661 wait_event(dasd_init_waitq, _wait_for_device(device));
662
663 dasd_reload_device(device);
664 if (device->discipline->kick_validate)
665 device->discipline->kick_validate(device);
666 }
667 EXPORT_SYMBOL(dasd_enable_device);
668
669 /*
670 * SECTION: device operation (interrupt handler, start i/o, term i/o ...)
671 */
672
673 unsigned int dasd_global_profile_level = DASD_PROFILE_OFF;
674
675 #ifdef CONFIG_DASD_PROFILE
676 struct dasd_profile dasd_global_profile = {
677 .lock = __SPIN_LOCK_UNLOCKED(dasd_global_profile.lock),
678 };
679 static struct dentry *dasd_debugfs_global_entry;
680
681 /*
682 * Add profiling information for cqr before execution.
683 */
684 static void dasd_profile_start(struct dasd_block *block,
685 struct dasd_ccw_req *cqr,
686 struct request *req)
687 {
688 struct list_head *l;
689 unsigned int counter;
690 struct dasd_device *device;
691
692 /* count the length of the chanq for statistics */
693 counter = 0;
694 if (dasd_global_profile_level || block->profile.data)
695 list_for_each(l, &block->ccw_queue)
696 if (++counter >= 31)
697 break;
698
699 spin_lock(&dasd_global_profile.lock);
700 if (dasd_global_profile.data) {
701 dasd_global_profile.data->dasd_io_nr_req[counter]++;
702 if (rq_data_dir(req) == READ)
703 dasd_global_profile.data->dasd_read_nr_req[counter]++;
704 }
705 spin_unlock(&dasd_global_profile.lock);
706
707 spin_lock(&block->profile.lock);
708 if (block->profile.data) {
709 block->profile.data->dasd_io_nr_req[counter]++;
710 if (rq_data_dir(req) == READ)
711 block->profile.data->dasd_read_nr_req[counter]++;
712 }
713 spin_unlock(&block->profile.lock);
714
715 /*
716 * We count the request for the start device, even though it may run on
717 * some other device due to error recovery. This way we make sure that
718 * we count each request only once.
719 */
720 device = cqr->startdev;
721 if (device->profile.data) {
722 counter = 1; /* request is not yet queued on the start device */
723 list_for_each(l, &device->ccw_queue)
724 if (++counter >= 31)
725 break;
726 }
727 spin_lock(&device->profile.lock);
728 if (device->profile.data) {
729 device->profile.data->dasd_io_nr_req[counter]++;
730 if (rq_data_dir(req) == READ)
731 device->profile.data->dasd_read_nr_req[counter]++;
732 }
733 spin_unlock(&device->profile.lock);
734 }
735
736 /*
737 * Add profiling information for cqr after execution.
738 */
739
740 #define dasd_profile_counter(value, index) \
741 { \
742 for (index = 0; index < 31 && value >> (2+index); index++) \
743 ; \
744 }
745
746 static void dasd_profile_end_add_data(struct dasd_profile_info *data,
747 int is_alias,
748 int is_tpm,
749 int is_read,
750 long sectors,
751 int sectors_ind,
752 int tottime_ind,
753 int tottimeps_ind,
754 int strtime_ind,
755 int irqtime_ind,
756 int irqtimeps_ind,
757 int endtime_ind)
758 {
759 /* in case of an overflow, reset the whole profile */
760 if (data->dasd_io_reqs == UINT_MAX) {
761 memset(data, 0, sizeof(*data));
762 ktime_get_real_ts64(&data->starttod);
763 }
764 data->dasd_io_reqs++;
765 data->dasd_io_sects += sectors;
766 if (is_alias)
767 data->dasd_io_alias++;
768 if (is_tpm)
769 data->dasd_io_tpm++;
770
771 data->dasd_io_secs[sectors_ind]++;
772 data->dasd_io_times[tottime_ind]++;
773 data->dasd_io_timps[tottimeps_ind]++;
774 data->dasd_io_time1[strtime_ind]++;
775 data->dasd_io_time2[irqtime_ind]++;
776 data->dasd_io_time2ps[irqtimeps_ind]++;
777 data->dasd_io_time3[endtime_ind]++;
778
779 if (is_read) {
780 data->dasd_read_reqs++;
781 data->dasd_read_sects += sectors;
782 if (is_alias)
783 data->dasd_read_alias++;
784 if (is_tpm)
785 data->dasd_read_tpm++;
786 data->dasd_read_secs[sectors_ind]++;
787 data->dasd_read_times[tottime_ind]++;
788 data->dasd_read_time1[strtime_ind]++;
789 data->dasd_read_time2[irqtime_ind]++;
790 data->dasd_read_time3[endtime_ind]++;
791 }
792 }
793
794 static void dasd_profile_end(struct dasd_block *block,
795 struct dasd_ccw_req *cqr,
796 struct request *req)
797 {
798 unsigned long strtime, irqtime, endtime, tottime;
799 unsigned long tottimeps, sectors;
800 struct dasd_device *device;
801 int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind;
802 int irqtime_ind, irqtimeps_ind, endtime_ind;
803 struct dasd_profile_info *data;
804
805 device = cqr->startdev;
806 if (!(dasd_global_profile_level ||
807 block->profile.data ||
808 device->profile.data))
809 return;
810
811 sectors = blk_rq_sectors(req);
812 if (!cqr->buildclk || !cqr->startclk ||
813 !cqr->stopclk || !cqr->endclk ||
814 !sectors)
815 return;
816
817 strtime = ((cqr->startclk - cqr->buildclk) >> 12);
818 irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
819 endtime = ((cqr->endclk - cqr->stopclk) >> 12);
820 tottime = ((cqr->endclk - cqr->buildclk) >> 12);
821 tottimeps = tottime / sectors;
822
823 dasd_profile_counter(sectors, sectors_ind);
824 dasd_profile_counter(tottime, tottime_ind);
825 dasd_profile_counter(tottimeps, tottimeps_ind);
826 dasd_profile_counter(strtime, strtime_ind);
827 dasd_profile_counter(irqtime, irqtime_ind);
828 dasd_profile_counter(irqtime / sectors, irqtimeps_ind);
829 dasd_profile_counter(endtime, endtime_ind);
830
831 spin_lock(&dasd_global_profile.lock);
832 if (dasd_global_profile.data) {
833 data = dasd_global_profile.data;
834 data->dasd_sum_times += tottime;
835 data->dasd_sum_time_str += strtime;
836 data->dasd_sum_time_irq += irqtime;
837 data->dasd_sum_time_end += endtime;
838 dasd_profile_end_add_data(dasd_global_profile.data,
839 cqr->startdev != block->base,
840 cqr->cpmode == 1,
841 rq_data_dir(req) == READ,
842 sectors, sectors_ind, tottime_ind,
843 tottimeps_ind, strtime_ind,
844 irqtime_ind, irqtimeps_ind,
845 endtime_ind);
846 }
847 spin_unlock(&dasd_global_profile.lock);
848
849 spin_lock(&block->profile.lock);
850 if (block->profile.data) {
851 data = block->profile.data;
852 data->dasd_sum_times += tottime;
853 data->dasd_sum_time_str += strtime;
854 data->dasd_sum_time_irq += irqtime;
855 data->dasd_sum_time_end += endtime;
856 dasd_profile_end_add_data(block->profile.data,
857 cqr->startdev != block->base,
858 cqr->cpmode == 1,
859 rq_data_dir(req) == READ,
860 sectors, sectors_ind, tottime_ind,
861 tottimeps_ind, strtime_ind,
862 irqtime_ind, irqtimeps_ind,
863 endtime_ind);
864 }
865 spin_unlock(&block->profile.lock);
866
867 spin_lock(&device->profile.lock);
868 if (device->profile.data) {
869 data = device->profile.data;
870 data->dasd_sum_times += tottime;
871 data->dasd_sum_time_str += strtime;
872 data->dasd_sum_time_irq += irqtime;
873 data->dasd_sum_time_end += endtime;
874 dasd_profile_end_add_data(device->profile.data,
875 cqr->startdev != block->base,
876 cqr->cpmode == 1,
877 rq_data_dir(req) == READ,
878 sectors, sectors_ind, tottime_ind,
879 tottimeps_ind, strtime_ind,
880 irqtime_ind, irqtimeps_ind,
881 endtime_ind);
882 }
883 spin_unlock(&device->profile.lock);
884 }
885
886 void dasd_profile_reset(struct dasd_profile *profile)
887 {
888 struct dasd_profile_info *data;
889
890 spin_lock_bh(&profile->lock);
891 data = profile->data;
892 if (!data) {
893 spin_unlock_bh(&profile->lock);
894 return;
895 }
896 memset(data, 0, sizeof(*data));
897 ktime_get_real_ts64(&data->starttod);
898 spin_unlock_bh(&profile->lock);
899 }
900
901 int dasd_profile_on(struct dasd_profile *profile)
902 {
903 struct dasd_profile_info *data;
904
905 data = kzalloc(sizeof(*data), GFP_KERNEL);
906 if (!data)
907 return -ENOMEM;
908 spin_lock_bh(&profile->lock);
909 if (profile->data) {
910 spin_unlock_bh(&profile->lock);
911 kfree(data);
912 return 0;
913 }
914 ktime_get_real_ts64(&data->starttod);
915 profile->data = data;
916 spin_unlock_bh(&profile->lock);
917 return 0;
918 }
919
920 void dasd_profile_off(struct dasd_profile *profile)
921 {
922 spin_lock_bh(&profile->lock);
923 kfree(profile->data);
924 profile->data = NULL;
925 spin_unlock_bh(&profile->lock);
926 }
927
928 char *dasd_get_user_string(const char __user *user_buf, size_t user_len)
929 {
930 char *buffer;
931
932 buffer = vmalloc(user_len + 1);
933 if (buffer == NULL)
934 return ERR_PTR(-ENOMEM);
935 if (copy_from_user(buffer, user_buf, user_len) != 0) {
936 vfree(buffer);
937 return ERR_PTR(-EFAULT);
938 }
939 /* got the string, now strip linefeed. */
940 if (buffer[user_len - 1] == '\n')
941 buffer[user_len - 1] = 0;
942 else
943 buffer[user_len] = 0;
944 return buffer;
945 }
946
947 static ssize_t dasd_stats_write(struct file *file,
948 const char __user *user_buf,
949 size_t user_len, loff_t *pos)
950 {
951 char *buffer, *str;
952 int rc;
953 struct seq_file *m = (struct seq_file *)file->private_data;
954 struct dasd_profile *prof = m->private;
955
956 if (user_len > 65536)
957 user_len = 65536;
958 buffer = dasd_get_user_string(user_buf, user_len);
959 if (IS_ERR(buffer))
960 return PTR_ERR(buffer);
961
962 str = skip_spaces(buffer);
963 rc = user_len;
964 if (strncmp(str, "reset", 5) == 0) {
965 dasd_profile_reset(prof);
966 } else if (strncmp(str, "on", 2) == 0) {
967 rc = dasd_profile_on(prof);
968 if (rc)
969 goto out;
970 rc = user_len;
971 if (prof == &dasd_global_profile) {
972 dasd_profile_reset(prof);
973 dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY;
974 }
975 } else if (strncmp(str, "off", 3) == 0) {
976 if (prof == &dasd_global_profile)
977 dasd_global_profile_level = DASD_PROFILE_OFF;
978 dasd_profile_off(prof);
979 } else
980 rc = -EINVAL;
981 out:
982 vfree(buffer);
983 return rc;
984 }
985
986 static void dasd_stats_array(struct seq_file *m, unsigned int *array)
987 {
988 int i;
989
990 for (i = 0; i < 32; i++)
991 seq_printf(m, "%u ", array[i]);
992 seq_putc(m, '\n');
993 }
994
995 static void dasd_stats_seq_print(struct seq_file *m,
996 struct dasd_profile_info *data)
997 {
998 seq_printf(m, "start_time %lld.%09ld\n",
999 (s64)data->starttod.tv_sec, data->starttod.tv_nsec);
1000 seq_printf(m, "total_requests %u\n", data->dasd_io_reqs);
1001 seq_printf(m, "total_sectors %u\n", data->dasd_io_sects);
1002 seq_printf(m, "total_pav %u\n", data->dasd_io_alias);
1003 seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm);
1004 seq_printf(m, "avg_total %lu\n", data->dasd_io_reqs ?
1005 data->dasd_sum_times / data->dasd_io_reqs : 0UL);
1006 seq_printf(m, "avg_build_to_ssch %lu\n", data->dasd_io_reqs ?
1007 data->dasd_sum_time_str / data->dasd_io_reqs : 0UL);
1008 seq_printf(m, "avg_ssch_to_irq %lu\n", data->dasd_io_reqs ?
1009 data->dasd_sum_time_irq / data->dasd_io_reqs : 0UL);
1010 seq_printf(m, "avg_irq_to_end %lu\n", data->dasd_io_reqs ?
1011 data->dasd_sum_time_end / data->dasd_io_reqs : 0UL);
1012 seq_puts(m, "histogram_sectors ");
1013 dasd_stats_array(m, data->dasd_io_secs);
1014 seq_puts(m, "histogram_io_times ");
1015 dasd_stats_array(m, data->dasd_io_times);
1016 seq_puts(m, "histogram_io_times_weighted ");
1017 dasd_stats_array(m, data->dasd_io_timps);
1018 seq_puts(m, "histogram_time_build_to_ssch ");
1019 dasd_stats_array(m, data->dasd_io_time1);
1020 seq_puts(m, "histogram_time_ssch_to_irq ");
1021 dasd_stats_array(m, data->dasd_io_time2);
1022 seq_puts(m, "histogram_time_ssch_to_irq_weighted ");
1023 dasd_stats_array(m, data->dasd_io_time2ps);
1024 seq_puts(m, "histogram_time_irq_to_end ");
1025 dasd_stats_array(m, data->dasd_io_time3);
1026 seq_puts(m, "histogram_ccw_queue_length ");
1027 dasd_stats_array(m, data->dasd_io_nr_req);
1028 seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs);
1029 seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects);
1030 seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias);
1031 seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm);
1032 seq_puts(m, "histogram_read_sectors ");
1033 dasd_stats_array(m, data->dasd_read_secs);
1034 seq_puts(m, "histogram_read_times ");
1035 dasd_stats_array(m, data->dasd_read_times);
1036 seq_puts(m, "histogram_read_time_build_to_ssch ");
1037 dasd_stats_array(m, data->dasd_read_time1);
1038 seq_puts(m, "histogram_read_time_ssch_to_irq ");
1039 dasd_stats_array(m, data->dasd_read_time2);
1040 seq_puts(m, "histogram_read_time_irq_to_end ");
1041 dasd_stats_array(m, data->dasd_read_time3);
1042 seq_puts(m, "histogram_read_ccw_queue_length ");
1043 dasd_stats_array(m, data->dasd_read_nr_req);
1044 }
1045
1046 static int dasd_stats_show(struct seq_file *m, void *v)
1047 {
1048 struct dasd_profile *profile;
1049 struct dasd_profile_info *data;
1050
1051 profile = m->private;
1052 spin_lock_bh(&profile->lock);
1053 data = profile->data;
1054 if (!data) {
1055 spin_unlock_bh(&profile->lock);
1056 seq_puts(m, "disabled\n");
1057 return 0;
1058 }
1059 dasd_stats_seq_print(m, data);
1060 spin_unlock_bh(&profile->lock);
1061 return 0;
1062 }
1063
1064 static int dasd_stats_open(struct inode *inode, struct file *file)
1065 {
1066 struct dasd_profile *profile = inode->i_private;
1067 return single_open(file, dasd_stats_show, profile);
1068 }
1069
1070 static const struct file_operations dasd_stats_raw_fops = {
1071 .owner = THIS_MODULE,
1072 .open = dasd_stats_open,
1073 .read = seq_read,
1074 .llseek = seq_lseek,
1075 .release = single_release,
1076 .write = dasd_stats_write,
1077 };
1078
1079 static void dasd_profile_init(struct dasd_profile *profile,
1080 struct dentry *base_dentry)
1081 {
1082 umode_t mode;
1083 struct dentry *pde;
1084
1085 if (!base_dentry)
1086 return;
1087 profile->dentry = NULL;
1088 profile->data = NULL;
1089 mode = (S_IRUSR | S_IWUSR | S_IFREG);
1090 pde = debugfs_create_file("statistics", mode, base_dentry,
1091 profile, &dasd_stats_raw_fops);
1092 if (pde && !IS_ERR(pde))
1093 profile->dentry = pde;
1094 return;
1095 }
1096
1097 static void dasd_profile_exit(struct dasd_profile *profile)
1098 {
1099 dasd_profile_off(profile);
1100 debugfs_remove(profile->dentry);
1101 profile->dentry = NULL;
1102 }
1103
1104 static void dasd_statistics_removeroot(void)
1105 {
1106 dasd_global_profile_level = DASD_PROFILE_OFF;
1107 dasd_profile_exit(&dasd_global_profile);
1108 debugfs_remove(dasd_debugfs_global_entry);
1109 debugfs_remove(dasd_debugfs_root_entry);
1110 }
1111
1112 static void dasd_statistics_createroot(void)
1113 {
1114 struct dentry *pde;
1115
1116 dasd_debugfs_root_entry = NULL;
1117 pde = debugfs_create_dir("dasd", NULL);
1118 if (!pde || IS_ERR(pde))
1119 goto error;
1120 dasd_debugfs_root_entry = pde;
1121 pde = debugfs_create_dir("global", dasd_debugfs_root_entry);
1122 if (!pde || IS_ERR(pde))
1123 goto error;
1124 dasd_debugfs_global_entry = pde;
1125 dasd_profile_init(&dasd_global_profile, dasd_debugfs_global_entry);
1126 return;
1127
1128 error:
1129 DBF_EVENT(DBF_ERR, "%s",
1130 "Creation of the dasd debugfs interface failed");
1131 dasd_statistics_removeroot();
1132 return;
1133 }
1134
1135 #else
1136 #define dasd_profile_start(block, cqr, req) do {} while (0)
1137 #define dasd_profile_end(block, cqr, req) do {} while (0)
1138
1139 static void dasd_statistics_createroot(void)
1140 {
1141 return;
1142 }
1143
1144 static void dasd_statistics_removeroot(void)
1145 {
1146 return;
1147 }
1148
1149 int dasd_stats_generic_show(struct seq_file *m, void *v)
1150 {
1151 seq_puts(m, "Statistics are not activated in this kernel\n");
1152 return 0;
1153 }
1154
1155 static void dasd_profile_init(struct dasd_profile *profile,
1156 struct dentry *base_dentry)
1157 {
1158 return;
1159 }
1160
1161 static void dasd_profile_exit(struct dasd_profile *profile)
1162 {
1163 return;
1164 }
1165
1166 int dasd_profile_on(struct dasd_profile *profile)
1167 {
1168 return 0;
1169 }
1170
1171 #endif /* CONFIG_DASD_PROFILE */
1172
1173 static int dasd_hosts_show(struct seq_file *m, void *v)
1174 {
1175 struct dasd_device *device;
1176 int rc = -EOPNOTSUPP;
1177
1178 device = m->private;
1179 dasd_get_device(device);
1180
1181 if (device->discipline->hosts_print)
1182 rc = device->discipline->hosts_print(device, m);
1183
1184 dasd_put_device(device);
1185 return rc;
1186 }
1187
1188 static int dasd_hosts_open(struct inode *inode, struct file *file)
1189 {
1190 struct dasd_device *device = inode->i_private;
1191
1192 return single_open(file, dasd_hosts_show, device);
1193 }
1194
1195 static const struct file_operations dasd_hosts_fops = {
1196 .owner = THIS_MODULE,
1197 .open = dasd_hosts_open,
1198 .read = seq_read,
1199 .llseek = seq_lseek,
1200 .release = single_release,
1201 };
1202
1203 static void dasd_hosts_exit(struct dasd_device *device)
1204 {
1205 debugfs_remove(device->hosts_dentry);
1206 device->hosts_dentry = NULL;
1207 }
1208
1209 static void dasd_hosts_init(struct dentry *base_dentry,
1210 struct dasd_device *device)
1211 {
1212 struct dentry *pde;
1213 umode_t mode;
1214
1215 if (!base_dentry)
1216 return;
1217
1218 mode = S_IRUSR | S_IFREG;
1219 pde = debugfs_create_file("host_access_list", mode, base_dentry,
1220 device, &dasd_hosts_fops);
1221 if (pde && !IS_ERR(pde))
1222 device->hosts_dentry = pde;
1223 }
1224
1225 /*
1226 * Allocate memory for a channel program with 'cplength' channel
1227 * command words and 'datasize' additional space. There are two
1228 * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed
1229 * memory and 2) dasd_smalloc_request uses the static ccw memory
1230 * that gets allocated for each device.
1231 */
1232 struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength,
1233 int datasize,
1234 struct dasd_device *device)
1235 {
1236 struct dasd_ccw_req *cqr;
1237
1238 /* Sanity checks */
1239 BUG_ON(datasize > PAGE_SIZE ||
1240 (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
1241
1242 cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
1243 if (cqr == NULL)
1244 return ERR_PTR(-ENOMEM);
1245 cqr->cpaddr = NULL;
1246 if (cplength > 0) {
1247 cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
1248 GFP_ATOMIC | GFP_DMA);
1249 if (cqr->cpaddr == NULL) {
1250 kfree(cqr);
1251 return ERR_PTR(-ENOMEM);
1252 }
1253 }
1254 cqr->data = NULL;
1255 if (datasize > 0) {
1256 cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA);
1257 if (cqr->data == NULL) {
1258 kfree(cqr->cpaddr);
1259 kfree(cqr);
1260 return ERR_PTR(-ENOMEM);
1261 }
1262 }
1263 cqr->magic = magic;
1264 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1265 dasd_get_device(device);
1266 return cqr;
1267 }
1268 EXPORT_SYMBOL(dasd_kmalloc_request);
1269
1270 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength,
1271 int datasize,
1272 struct dasd_device *device)
1273 {
1274 unsigned long flags;
1275 struct dasd_ccw_req *cqr;
1276 char *data;
1277 int size;
1278
1279 size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
1280 if (cplength > 0)
1281 size += cplength * sizeof(struct ccw1);
1282 if (datasize > 0)
1283 size += datasize;
1284 spin_lock_irqsave(&device->mem_lock, flags);
1285 cqr = (struct dasd_ccw_req *)
1286 dasd_alloc_chunk(&device->ccw_chunks, size);
1287 spin_unlock_irqrestore(&device->mem_lock, flags);
1288 if (cqr == NULL)
1289 return ERR_PTR(-ENOMEM);
1290 memset(cqr, 0, sizeof(struct dasd_ccw_req));
1291 data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
1292 cqr->cpaddr = NULL;
1293 if (cplength > 0) {
1294 cqr->cpaddr = (struct ccw1 *) data;
1295 data += cplength*sizeof(struct ccw1);
1296 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
1297 }
1298 cqr->data = NULL;
1299 if (datasize > 0) {
1300 cqr->data = data;
1301 memset(cqr->data, 0, datasize);
1302 }
1303 cqr->magic = magic;
1304 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1305 dasd_get_device(device);
1306 return cqr;
1307 }
1308 EXPORT_SYMBOL(dasd_smalloc_request);
1309
1310 /*
1311 * Free memory of a channel program. This function needs to free all the
1312 * idal lists that might have been created by dasd_set_cda and the
1313 * struct dasd_ccw_req itself.
1314 */
1315 void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1316 {
1317 struct ccw1 *ccw;
1318
1319 /* Clear any idals used for the request. */
1320 ccw = cqr->cpaddr;
1321 do {
1322 clear_normalized_cda(ccw);
1323 } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
1324 kfree(cqr->cpaddr);
1325 kfree(cqr->data);
1326 kfree(cqr);
1327 dasd_put_device(device);
1328 }
1329 EXPORT_SYMBOL(dasd_kfree_request);
1330
1331 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1332 {
1333 unsigned long flags;
1334
1335 spin_lock_irqsave(&device->mem_lock, flags);
1336 dasd_free_chunk(&device->ccw_chunks, cqr);
1337 spin_unlock_irqrestore(&device->mem_lock, flags);
1338 dasd_put_device(device);
1339 }
1340 EXPORT_SYMBOL(dasd_sfree_request);
1341
1342 /*
1343 * Check discipline magic in cqr.
1344 */
1345 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
1346 {
1347 struct dasd_device *device;
1348
1349 if (cqr == NULL)
1350 return -EINVAL;
1351 device = cqr->startdev;
1352 if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
1353 DBF_DEV_EVENT(DBF_WARNING, device,
1354 " dasd_ccw_req 0x%08x magic doesn't match"
1355 " discipline 0x%08x",
1356 cqr->magic,
1357 *(unsigned int *) device->discipline->name);
1358 return -EINVAL;
1359 }
1360 return 0;
1361 }
1362
1363 /*
1364 * Terminate the current i/o and set the request to clear_pending.
1365 * Timer keeps device runnig.
1366 * ccw_device_clear can fail if the i/o subsystem
1367 * is in a bad mood.
1368 */
1369 int dasd_term_IO(struct dasd_ccw_req *cqr)
1370 {
1371 struct dasd_device *device;
1372 int retries, rc;
1373 char errorstring[ERRORLENGTH];
1374
1375 /* Check the cqr */
1376 rc = dasd_check_cqr(cqr);
1377 if (rc)
1378 return rc;
1379 retries = 0;
1380 device = (struct dasd_device *) cqr->startdev;
1381 while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
1382 rc = ccw_device_clear(device->cdev, (long) cqr);
1383 switch (rc) {
1384 case 0: /* termination successful */
1385 cqr->status = DASD_CQR_CLEAR_PENDING;
1386 cqr->stopclk = get_tod_clock();
1387 cqr->starttime = 0;
1388 DBF_DEV_EVENT(DBF_DEBUG, device,
1389 "terminate cqr %p successful",
1390 cqr);
1391 break;
1392 case -ENODEV:
1393 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1394 "device gone, retry");
1395 break;
1396 case -EINVAL:
1397 /*
1398 * device not valid so no I/O could be running
1399 * handle CQR as termination successful
1400 */
1401 cqr->status = DASD_CQR_CLEARED;
1402 cqr->stopclk = get_tod_clock();
1403 cqr->starttime = 0;
1404 /* no retries for invalid devices */
1405 cqr->retries = -1;
1406 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1407 "EINVAL, handle as terminated");
1408 /* fake rc to success */
1409 rc = 0;
1410 break;
1411 default:
1412 /* internal error 10 - unknown rc*/
1413 snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
1414 dev_err(&device->cdev->dev, "An error occurred in the "
1415 "DASD device driver, reason=%s\n", errorstring);
1416 BUG();
1417 break;
1418 }
1419 retries++;
1420 }
1421 dasd_schedule_device_bh(device);
1422 return rc;
1423 }
1424 EXPORT_SYMBOL(dasd_term_IO);
1425
1426 /*
1427 * Start the i/o. This start_IO can fail if the channel is really busy.
1428 * In that case set up a timer to start the request later.
1429 */
1430 int dasd_start_IO(struct dasd_ccw_req *cqr)
1431 {
1432 struct dasd_device *device;
1433 int rc;
1434 char errorstring[ERRORLENGTH];
1435
1436 /* Check the cqr */
1437 rc = dasd_check_cqr(cqr);
1438 if (rc) {
1439 cqr->intrc = rc;
1440 return rc;
1441 }
1442 device = (struct dasd_device *) cqr->startdev;
1443 if (((cqr->block &&
1444 test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) ||
1445 test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) &&
1446 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
1447 DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p "
1448 "because of stolen lock", cqr);
1449 cqr->status = DASD_CQR_ERROR;
1450 cqr->intrc = -EPERM;
1451 return -EPERM;
1452 }
1453 if (cqr->retries < 0) {
1454 /* internal error 14 - start_IO run out of retries */
1455 sprintf(errorstring, "14 %p", cqr);
1456 dev_err(&device->cdev->dev, "An error occurred in the DASD "
1457 "device driver, reason=%s\n", errorstring);
1458 cqr->status = DASD_CQR_ERROR;
1459 return -EIO;
1460 }
1461 cqr->startclk = get_tod_clock();
1462 cqr->starttime = jiffies;
1463 cqr->retries--;
1464 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1465 cqr->lpm &= dasd_path_get_opm(device);
1466 if (!cqr->lpm)
1467 cqr->lpm = dasd_path_get_opm(device);
1468 }
1469 if (cqr->cpmode == 1) {
1470 rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
1471 (long) cqr, cqr->lpm);
1472 } else {
1473 rc = ccw_device_start(device->cdev, cqr->cpaddr,
1474 (long) cqr, cqr->lpm, 0);
1475 }
1476 switch (rc) {
1477 case 0:
1478 cqr->status = DASD_CQR_IN_IO;
1479 break;
1480 case -EBUSY:
1481 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1482 "start_IO: device busy, retry later");
1483 break;
1484 case -EACCES:
1485 /* -EACCES indicates that the request used only a subset of the
1486 * available paths and all these paths are gone. If the lpm of
1487 * this request was only a subset of the opm (e.g. the ppm) then
1488 * we just do a retry with all available paths.
1489 * If we already use the full opm, something is amiss, and we
1490 * need a full path verification.
1491 */
1492 if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1493 DBF_DEV_EVENT(DBF_WARNING, device,
1494 "start_IO: selected paths gone (%x)",
1495 cqr->lpm);
1496 } else if (cqr->lpm != dasd_path_get_opm(device)) {
1497 cqr->lpm = dasd_path_get_opm(device);
1498 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
1499 "start_IO: selected paths gone,"
1500 " retry on all paths");
1501 } else {
1502 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1503 "start_IO: all paths in opm gone,"
1504 " do path verification");
1505 dasd_generic_last_path_gone(device);
1506 dasd_path_no_path(device);
1507 dasd_path_set_tbvpm(device,
1508 ccw_device_get_path_mask(
1509 device->cdev));
1510 }
1511 break;
1512 case -ENODEV:
1513 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1514 "start_IO: -ENODEV device gone, retry");
1515 break;
1516 case -EIO:
1517 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1518 "start_IO: -EIO device gone, retry");
1519 break;
1520 case -EINVAL:
1521 /* most likely caused in power management context */
1522 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1523 "start_IO: -EINVAL device currently "
1524 "not accessible");
1525 break;
1526 default:
1527 /* internal error 11 - unknown rc */
1528 snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
1529 dev_err(&device->cdev->dev,
1530 "An error occurred in the DASD device driver, "
1531 "reason=%s\n", errorstring);
1532 BUG();
1533 break;
1534 }
1535 cqr->intrc = rc;
1536 return rc;
1537 }
1538 EXPORT_SYMBOL(dasd_start_IO);
1539
1540 /*
1541 * Timeout function for dasd devices. This is used for different purposes
1542 * 1) missing interrupt handler for normal operation
1543 * 2) delayed start of request where start_IO failed with -EBUSY
1544 * 3) timeout for missing state change interrupts
1545 * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
1546 * DASD_CQR_QUEUED for 2) and 3).
1547 */
1548 static void dasd_device_timeout(struct timer_list *t)
1549 {
1550 unsigned long flags;
1551 struct dasd_device *device;
1552
1553 device = from_timer(device, t, timer);
1554 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1555 /* re-activate request queue */
1556 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1557 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1558 dasd_schedule_device_bh(device);
1559 }
1560
1561 /*
1562 * Setup timeout for a device in jiffies.
1563 */
1564 void dasd_device_set_timer(struct dasd_device *device, int expires)
1565 {
1566 if (expires == 0)
1567 del_timer(&device->timer);
1568 else
1569 mod_timer(&device->timer, jiffies + expires);
1570 }
1571 EXPORT_SYMBOL(dasd_device_set_timer);
1572
1573 /*
1574 * Clear timeout for a device.
1575 */
1576 void dasd_device_clear_timer(struct dasd_device *device)
1577 {
1578 del_timer(&device->timer);
1579 }
1580 EXPORT_SYMBOL(dasd_device_clear_timer);
1581
1582 static void dasd_handle_killed_request(struct ccw_device *cdev,
1583 unsigned long intparm)
1584 {
1585 struct dasd_ccw_req *cqr;
1586 struct dasd_device *device;
1587
1588 if (!intparm)
1589 return;
1590 cqr = (struct dasd_ccw_req *) intparm;
1591 if (cqr->status != DASD_CQR_IN_IO) {
1592 DBF_EVENT_DEVID(DBF_DEBUG, cdev,
1593 "invalid status in handle_killed_request: "
1594 "%02x", cqr->status);
1595 return;
1596 }
1597
1598 device = dasd_device_from_cdev_locked(cdev);
1599 if (IS_ERR(device)) {
1600 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1601 "unable to get device from cdev");
1602 return;
1603 }
1604
1605 if (!cqr->startdev ||
1606 device != cqr->startdev ||
1607 strncmp(cqr->startdev->discipline->ebcname,
1608 (char *) &cqr->magic, 4)) {
1609 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1610 "invalid device in request");
1611 dasd_put_device(device);
1612 return;
1613 }
1614
1615 /* Schedule request to be retried. */
1616 cqr->status = DASD_CQR_QUEUED;
1617
1618 dasd_device_clear_timer(device);
1619 dasd_schedule_device_bh(device);
1620 dasd_put_device(device);
1621 }
1622
1623 void dasd_generic_handle_state_change(struct dasd_device *device)
1624 {
1625 /* First of all start sense subsystem status request. */
1626 dasd_eer_snss(device);
1627
1628 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1629 dasd_schedule_device_bh(device);
1630 if (device->block) {
1631 dasd_schedule_block_bh(device->block);
1632 if (device->block->request_queue)
1633 blk_mq_run_hw_queues(device->block->request_queue,
1634 true);
1635 }
1636 }
1637 EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
1638
1639 static int dasd_check_hpf_error(struct irb *irb)
1640 {
1641 return (scsw_tm_is_valid_schxs(&irb->scsw) &&
1642 (irb->scsw.tm.sesq == SCSW_SESQ_DEV_NOFCX ||
1643 irb->scsw.tm.sesq == SCSW_SESQ_PATH_NOFCX));
1644 }
1645
1646 /*
1647 * Interrupt handler for "normal" ssch-io based dasd devices.
1648 */
1649 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
1650 struct irb *irb)
1651 {
1652 struct dasd_ccw_req *cqr, *next;
1653 struct dasd_device *device;
1654 unsigned long now;
1655 int nrf_suppressed = 0;
1656 int fp_suppressed = 0;
1657 u8 *sense = NULL;
1658 int expires;
1659
1660 cqr = (struct dasd_ccw_req *) intparm;
1661 if (IS_ERR(irb)) {
1662 switch (PTR_ERR(irb)) {
1663 case -EIO:
1664 if (cqr && cqr->status == DASD_CQR_CLEAR_PENDING) {
1665 device = cqr->startdev;
1666 cqr->status = DASD_CQR_CLEARED;
1667 dasd_device_clear_timer(device);
1668 wake_up(&dasd_flush_wq);
1669 dasd_schedule_device_bh(device);
1670 return;
1671 }
1672 break;
1673 case -ETIMEDOUT:
1674 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1675 "request timed out\n", __func__);
1676 break;
1677 default:
1678 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1679 "unknown error %ld\n", __func__,
1680 PTR_ERR(irb));
1681 }
1682 dasd_handle_killed_request(cdev, intparm);
1683 return;
1684 }
1685
1686 now = get_tod_clock();
1687 /* check for conditions that should be handled immediately */
1688 if (!cqr ||
1689 !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1690 scsw_cstat(&irb->scsw) == 0)) {
1691 if (cqr)
1692 memcpy(&cqr->irb, irb, sizeof(*irb));
1693 device = dasd_device_from_cdev_locked(cdev);
1694 if (IS_ERR(device))
1695 return;
1696 /* ignore unsolicited interrupts for DIAG discipline */
1697 if (device->discipline == dasd_diag_discipline_pointer) {
1698 dasd_put_device(device);
1699 return;
1700 }
1701
1702 /*
1703 * In some cases 'File Protected' or 'No Record Found' errors
1704 * might be expected and debug log messages for the
1705 * corresponding interrupts shouldn't be written then.
1706 * Check if either of the according suppress bits is set.
1707 */
1708 sense = dasd_get_sense(irb);
1709 if (sense) {
1710 fp_suppressed = (sense[1] & SNS1_FILE_PROTECTED) &&
1711 test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags);
1712 nrf_suppressed = (sense[1] & SNS1_NO_REC_FOUND) &&
1713 test_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags);
1714 }
1715 if (!(fp_suppressed || nrf_suppressed))
1716 device->discipline->dump_sense_dbf(device, irb, "int");
1717
1718 if (device->features & DASD_FEATURE_ERPLOG)
1719 device->discipline->dump_sense(device, cqr, irb);
1720 device->discipline->check_for_device_change(device, cqr, irb);
1721 dasd_put_device(device);
1722 }
1723
1724 /* check for for attention message */
1725 if (scsw_dstat(&irb->scsw) & DEV_STAT_ATTENTION) {
1726 device = dasd_device_from_cdev_locked(cdev);
1727 if (!IS_ERR(device)) {
1728 device->discipline->check_attention(device,
1729 irb->esw.esw1.lpum);
1730 dasd_put_device(device);
1731 }
1732 }
1733
1734 if (!cqr)
1735 return;
1736
1737 device = (struct dasd_device *) cqr->startdev;
1738 if (!device ||
1739 strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
1740 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1741 "invalid device in request");
1742 return;
1743 }
1744
1745 /* Check for clear pending */
1746 if (cqr->status == DASD_CQR_CLEAR_PENDING &&
1747 scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
1748 cqr->status = DASD_CQR_CLEARED;
1749 dasd_device_clear_timer(device);
1750 wake_up(&dasd_flush_wq);
1751 dasd_schedule_device_bh(device);
1752 return;
1753 }
1754
1755 /* check status - the request might have been killed by dyn detach */
1756 if (cqr->status != DASD_CQR_IN_IO) {
1757 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
1758 "status %02x", dev_name(&cdev->dev), cqr->status);
1759 return;
1760 }
1761
1762 next = NULL;
1763 expires = 0;
1764 if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1765 scsw_cstat(&irb->scsw) == 0) {
1766 /* request was completed successfully */
1767 cqr->status = DASD_CQR_SUCCESS;
1768 cqr->stopclk = now;
1769 /* Start first request on queue if possible -> fast_io. */
1770 if (cqr->devlist.next != &device->ccw_queue) {
1771 next = list_entry(cqr->devlist.next,
1772 struct dasd_ccw_req, devlist);
1773 }
1774 } else { /* error */
1775 /* check for HPF error
1776 * call discipline function to requeue all requests
1777 * and disable HPF accordingly
1778 */
1779 if (cqr->cpmode && dasd_check_hpf_error(irb) &&
1780 device->discipline->handle_hpf_error)
1781 device->discipline->handle_hpf_error(device, irb);
1782 /*
1783 * If we don't want complex ERP for this request, then just
1784 * reset this and retry it in the fastpath
1785 */
1786 if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
1787 cqr->retries > 0) {
1788 if (cqr->lpm == dasd_path_get_opm(device))
1789 DBF_DEV_EVENT(DBF_DEBUG, device,
1790 "default ERP in fastpath "
1791 "(%i retries left)",
1792 cqr->retries);
1793 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))
1794 cqr->lpm = dasd_path_get_opm(device);
1795 cqr->status = DASD_CQR_QUEUED;
1796 next = cqr;
1797 } else
1798 cqr->status = DASD_CQR_ERROR;
1799 }
1800 if (next && (next->status == DASD_CQR_QUEUED) &&
1801 (!device->stopped)) {
1802 if (device->discipline->start_IO(next) == 0)
1803 expires = next->expires;
1804 }
1805 if (expires != 0)
1806 dasd_device_set_timer(device, expires);
1807 else
1808 dasd_device_clear_timer(device);
1809 dasd_schedule_device_bh(device);
1810 }
1811 EXPORT_SYMBOL(dasd_int_handler);
1812
1813 enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb)
1814 {
1815 struct dasd_device *device;
1816
1817 device = dasd_device_from_cdev_locked(cdev);
1818
1819 if (IS_ERR(device))
1820 goto out;
1821 if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
1822 device->state != device->target ||
1823 !device->discipline->check_for_device_change){
1824 dasd_put_device(device);
1825 goto out;
1826 }
1827 if (device->discipline->dump_sense_dbf)
1828 device->discipline->dump_sense_dbf(device, irb, "uc");
1829 device->discipline->check_for_device_change(device, NULL, irb);
1830 dasd_put_device(device);
1831 out:
1832 return UC_TODO_RETRY;
1833 }
1834 EXPORT_SYMBOL_GPL(dasd_generic_uc_handler);
1835
1836 /*
1837 * If we have an error on a dasd_block layer request then we cancel
1838 * and return all further requests from the same dasd_block as well.
1839 */
1840 static void __dasd_device_recovery(struct dasd_device *device,
1841 struct dasd_ccw_req *ref_cqr)
1842 {
1843 struct list_head *l, *n;
1844 struct dasd_ccw_req *cqr;
1845
1846 /*
1847 * only requeue request that came from the dasd_block layer
1848 */
1849 if (!ref_cqr->block)
1850 return;
1851
1852 list_for_each_safe(l, n, &device->ccw_queue) {
1853 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1854 if (cqr->status == DASD_CQR_QUEUED &&
1855 ref_cqr->block == cqr->block) {
1856 cqr->status = DASD_CQR_CLEARED;
1857 }
1858 }
1859 };
1860
1861 /*
1862 * Remove those ccw requests from the queue that need to be returned
1863 * to the upper layer.
1864 */
1865 static void __dasd_device_process_ccw_queue(struct dasd_device *device,
1866 struct list_head *final_queue)
1867 {
1868 struct list_head *l, *n;
1869 struct dasd_ccw_req *cqr;
1870
1871 /* Process request with final status. */
1872 list_for_each_safe(l, n, &device->ccw_queue) {
1873 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1874
1875 /* Skip any non-final request. */
1876 if (cqr->status == DASD_CQR_QUEUED ||
1877 cqr->status == DASD_CQR_IN_IO ||
1878 cqr->status == DASD_CQR_CLEAR_PENDING)
1879 continue;
1880 if (cqr->status == DASD_CQR_ERROR) {
1881 __dasd_device_recovery(device, cqr);
1882 }
1883 /* Rechain finished requests to final queue */
1884 list_move_tail(&cqr->devlist, final_queue);
1885 }
1886 }
1887
1888 /*
1889 * the cqrs from the final queue are returned to the upper layer
1890 * by setting a dasd_block state and calling the callback function
1891 */
1892 static void __dasd_device_process_final_queue(struct dasd_device *device,
1893 struct list_head *final_queue)
1894 {
1895 struct list_head *l, *n;
1896 struct dasd_ccw_req *cqr;
1897 struct dasd_block *block;
1898 void (*callback)(struct dasd_ccw_req *, void *data);
1899 void *callback_data;
1900 char errorstring[ERRORLENGTH];
1901
1902 list_for_each_safe(l, n, final_queue) {
1903 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1904 list_del_init(&cqr->devlist);
1905 block = cqr->block;
1906 callback = cqr->callback;
1907 callback_data = cqr->callback_data;
1908 if (block)
1909 spin_lock_bh(&block->queue_lock);
1910 switch (cqr->status) {
1911 case DASD_CQR_SUCCESS:
1912 cqr->status = DASD_CQR_DONE;
1913 break;
1914 case DASD_CQR_ERROR:
1915 cqr->status = DASD_CQR_NEED_ERP;
1916 break;
1917 case DASD_CQR_CLEARED:
1918 cqr->status = DASD_CQR_TERMINATED;
1919 break;
1920 default:
1921 /* internal error 12 - wrong cqr status*/
1922 snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
1923 dev_err(&device->cdev->dev,
1924 "An error occurred in the DASD device driver, "
1925 "reason=%s\n", errorstring);
1926 BUG();
1927 }
1928 if (cqr->callback != NULL)
1929 (callback)(cqr, callback_data);
1930 if (block)
1931 spin_unlock_bh(&block->queue_lock);
1932 }
1933 }
1934
1935 /*
1936 * Take a look at the first request on the ccw queue and check
1937 * if it reached its expire time. If so, terminate the IO.
1938 */
1939 static void __dasd_device_check_expire(struct dasd_device *device)
1940 {
1941 struct dasd_ccw_req *cqr;
1942
1943 if (list_empty(&device->ccw_queue))
1944 return;
1945 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1946 if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
1947 (time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
1948 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
1949 /*
1950 * IO in safe offline processing should not
1951 * run out of retries
1952 */
1953 cqr->retries++;
1954 }
1955 if (device->discipline->term_IO(cqr) != 0) {
1956 /* Hmpf, try again in 5 sec */
1957 dev_err(&device->cdev->dev,
1958 "cqr %p timed out (%lus) but cannot be "
1959 "ended, retrying in 5 s\n",
1960 cqr, (cqr->expires/HZ));
1961 cqr->expires += 5*HZ;
1962 dasd_device_set_timer(device, 5*HZ);
1963 } else {
1964 dev_err(&device->cdev->dev,
1965 "cqr %p timed out (%lus), %i retries "
1966 "remaining\n", cqr, (cqr->expires/HZ),
1967 cqr->retries);
1968 }
1969 }
1970 }
1971
1972 /*
1973 * return 1 when device is not eligible for IO
1974 */
1975 static int __dasd_device_is_unusable(struct dasd_device *device,
1976 struct dasd_ccw_req *cqr)
1977 {
1978 int mask = ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM);
1979
1980 if (test_bit(DASD_FLAG_OFFLINE, &device->flags) &&
1981 !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
1982 /*
1983 * dasd is being set offline
1984 * but it is no safe offline where we have to allow I/O
1985 */
1986 return 1;
1987 }
1988 if (device->stopped) {
1989 if (device->stopped & mask) {
1990 /* stopped and CQR will not change that. */
1991 return 1;
1992 }
1993 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1994 /* CQR is not able to change device to
1995 * operational. */
1996 return 1;
1997 }
1998 /* CQR required to get device operational. */
1999 }
2000 return 0;
2001 }
2002
2003 /*
2004 * Take a look at the first request on the ccw queue and check
2005 * if it needs to be started.
2006 */
2007 static void __dasd_device_start_head(struct dasd_device *device)
2008 {
2009 struct dasd_ccw_req *cqr;
2010 int rc;
2011
2012 if (list_empty(&device->ccw_queue))
2013 return;
2014 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2015 if (cqr->status != DASD_CQR_QUEUED)
2016 return;
2017 /* if device is not usable return request to upper layer */
2018 if (__dasd_device_is_unusable(device, cqr)) {
2019 cqr->intrc = -EAGAIN;
2020 cqr->status = DASD_CQR_CLEARED;
2021 dasd_schedule_device_bh(device);
2022 return;
2023 }
2024
2025 rc = device->discipline->start_IO(cqr);
2026 if (rc == 0)
2027 dasd_device_set_timer(device, cqr->expires);
2028 else if (rc == -EACCES) {
2029 dasd_schedule_device_bh(device);
2030 } else
2031 /* Hmpf, try again in 1/2 sec */
2032 dasd_device_set_timer(device, 50);
2033 }
2034
2035 static void __dasd_device_check_path_events(struct dasd_device *device)
2036 {
2037 int rc;
2038
2039 if (!dasd_path_get_tbvpm(device))
2040 return;
2041
2042 if (device->stopped &
2043 ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
2044 return;
2045 rc = device->discipline->verify_path(device,
2046 dasd_path_get_tbvpm(device));
2047 if (rc)
2048 dasd_device_set_timer(device, 50);
2049 else
2050 dasd_path_clear_all_verify(device);
2051 };
2052
2053 /*
2054 * Go through all request on the dasd_device request queue,
2055 * terminate them on the cdev if necessary, and return them to the
2056 * submitting layer via callback.
2057 * Note:
2058 * Make sure that all 'submitting layers' still exist when
2059 * this function is called!. In other words, when 'device' is a base
2060 * device then all block layer requests must have been removed before
2061 * via dasd_flush_block_queue.
2062 */
2063 int dasd_flush_device_queue(struct dasd_device *device)
2064 {
2065 struct dasd_ccw_req *cqr, *n;
2066 int rc;
2067 struct list_head flush_queue;
2068
2069 INIT_LIST_HEAD(&flush_queue);
2070 spin_lock_irq(get_ccwdev_lock(device->cdev));
2071 rc = 0;
2072 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
2073 /* Check status and move request to flush_queue */
2074 switch (cqr->status) {
2075 case DASD_CQR_IN_IO:
2076 rc = device->discipline->term_IO(cqr);
2077 if (rc) {
2078 /* unable to terminate requeust */
2079 dev_err(&device->cdev->dev,
2080 "Flushing the DASD request queue "
2081 "failed for request %p\n", cqr);
2082 /* stop flush processing */
2083 goto finished;
2084 }
2085 break;
2086 case DASD_CQR_QUEUED:
2087 cqr->stopclk = get_tod_clock();
2088 cqr->status = DASD_CQR_CLEARED;
2089 break;
2090 default: /* no need to modify the others */
2091 break;
2092 }
2093 list_move_tail(&cqr->devlist, &flush_queue);
2094 }
2095 finished:
2096 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2097 /*
2098 * After this point all requests must be in state CLEAR_PENDING,
2099 * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
2100 * one of the others.
2101 */
2102 list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
2103 wait_event(dasd_flush_wq,
2104 (cqr->status != DASD_CQR_CLEAR_PENDING));
2105 /*
2106 * Now set each request back to TERMINATED, DONE or NEED_ERP
2107 * and call the callback function of flushed requests
2108 */
2109 __dasd_device_process_final_queue(device, &flush_queue);
2110 return rc;
2111 }
2112 EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
2113
2114 /*
2115 * Acquire the device lock and process queues for the device.
2116 */
2117 static void dasd_device_tasklet(struct dasd_device *device)
2118 {
2119 struct list_head final_queue;
2120
2121 atomic_set (&device->tasklet_scheduled, 0);
2122 INIT_LIST_HEAD(&final_queue);
2123 spin_lock_irq(get_ccwdev_lock(device->cdev));
2124 /* Check expire time of first request on the ccw queue. */
2125 __dasd_device_check_expire(device);
2126 /* find final requests on ccw queue */
2127 __dasd_device_process_ccw_queue(device, &final_queue);
2128 __dasd_device_check_path_events(device);
2129 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2130 /* Now call the callback function of requests with final status */
2131 __dasd_device_process_final_queue(device, &final_queue);
2132 spin_lock_irq(get_ccwdev_lock(device->cdev));
2133 /* Now check if the head of the ccw queue needs to be started. */
2134 __dasd_device_start_head(device);
2135 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2136 if (waitqueue_active(&shutdown_waitq))
2137 wake_up(&shutdown_waitq);
2138 dasd_put_device(device);
2139 }
2140
2141 /*
2142 * Schedules a call to dasd_tasklet over the device tasklet.
2143 */
2144 void dasd_schedule_device_bh(struct dasd_device *device)
2145 {
2146 /* Protect against rescheduling. */
2147 if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
2148 return;
2149 dasd_get_device(device);
2150 tasklet_hi_schedule(&device->tasklet);
2151 }
2152 EXPORT_SYMBOL(dasd_schedule_device_bh);
2153
2154 void dasd_device_set_stop_bits(struct dasd_device *device, int bits)
2155 {
2156 device->stopped |= bits;
2157 }
2158 EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits);
2159
2160 void dasd_device_remove_stop_bits(struct dasd_device *device, int bits)
2161 {
2162 device->stopped &= ~bits;
2163 if (!device->stopped)
2164 wake_up(&generic_waitq);
2165 }
2166 EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits);
2167
2168 /*
2169 * Queue a request to the head of the device ccw_queue.
2170 * Start the I/O if possible.
2171 */
2172 void dasd_add_request_head(struct dasd_ccw_req *cqr)
2173 {
2174 struct dasd_device *device;
2175 unsigned long flags;
2176
2177 device = cqr->startdev;
2178 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2179 cqr->status = DASD_CQR_QUEUED;
2180 list_add(&cqr->devlist, &device->ccw_queue);
2181 /* let the bh start the request to keep them in order */
2182 dasd_schedule_device_bh(device);
2183 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2184 }
2185 EXPORT_SYMBOL(dasd_add_request_head);
2186
2187 /*
2188 * Queue a request to the tail of the device ccw_queue.
2189 * Start the I/O if possible.
2190 */
2191 void dasd_add_request_tail(struct dasd_ccw_req *cqr)
2192 {
2193 struct dasd_device *device;
2194 unsigned long flags;
2195
2196 device = cqr->startdev;
2197 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2198 cqr->status = DASD_CQR_QUEUED;
2199 list_add_tail(&cqr->devlist, &device->ccw_queue);
2200 /* let the bh start the request to keep them in order */
2201 dasd_schedule_device_bh(device);
2202 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2203 }
2204 EXPORT_SYMBOL(dasd_add_request_tail);
2205
2206 /*
2207 * Wakeup helper for the 'sleep_on' functions.
2208 */
2209 void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
2210 {
2211 spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2212 cqr->callback_data = DASD_SLEEPON_END_TAG;
2213 spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2214 wake_up(&generic_waitq);
2215 }
2216 EXPORT_SYMBOL_GPL(dasd_wakeup_cb);
2217
2218 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
2219 {
2220 struct dasd_device *device;
2221 int rc;
2222
2223 device = cqr->startdev;
2224 spin_lock_irq(get_ccwdev_lock(device->cdev));
2225 rc = (cqr->callback_data == DASD_SLEEPON_END_TAG);
2226 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2227 return rc;
2228 }
2229
2230 /*
2231 * checks if error recovery is necessary, returns 1 if yes, 0 otherwise.
2232 */
2233 static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr)
2234 {
2235 struct dasd_device *device;
2236 dasd_erp_fn_t erp_fn;
2237
2238 if (cqr->status == DASD_CQR_FILLED)
2239 return 0;
2240 device = cqr->startdev;
2241 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2242 if (cqr->status == DASD_CQR_TERMINATED) {
2243 device->discipline->handle_terminated_request(cqr);
2244 return 1;
2245 }
2246 if (cqr->status == DASD_CQR_NEED_ERP) {
2247 erp_fn = device->discipline->erp_action(cqr);
2248 erp_fn(cqr);
2249 return 1;
2250 }
2251 if (cqr->status == DASD_CQR_FAILED)
2252 dasd_log_sense(cqr, &cqr->irb);
2253 if (cqr->refers) {
2254 __dasd_process_erp(device, cqr);
2255 return 1;
2256 }
2257 }
2258 return 0;
2259 }
2260
2261 static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr)
2262 {
2263 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2264 if (cqr->refers) /* erp is not done yet */
2265 return 1;
2266 return ((cqr->status != DASD_CQR_DONE) &&
2267 (cqr->status != DASD_CQR_FAILED));
2268 } else
2269 return (cqr->status == DASD_CQR_FILLED);
2270 }
2271
2272 static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
2273 {
2274 struct dasd_device *device;
2275 int rc;
2276 struct list_head ccw_queue;
2277 struct dasd_ccw_req *cqr;
2278
2279 INIT_LIST_HEAD(&ccw_queue);
2280 maincqr->status = DASD_CQR_FILLED;
2281 device = maincqr->startdev;
2282 list_add(&maincqr->blocklist, &ccw_queue);
2283 for (cqr = maincqr; __dasd_sleep_on_loop_condition(cqr);
2284 cqr = list_first_entry(&ccw_queue,
2285 struct dasd_ccw_req, blocklist)) {
2286
2287 if (__dasd_sleep_on_erp(cqr))
2288 continue;
2289 if (cqr->status != DASD_CQR_FILLED) /* could be failed */
2290 continue;
2291 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2292 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2293 cqr->status = DASD_CQR_FAILED;
2294 cqr->intrc = -EPERM;
2295 continue;
2296 }
2297 /* Non-temporary stop condition will trigger fail fast */
2298 if (device->stopped & ~DASD_STOPPED_PENDING &&
2299 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2300 (!dasd_eer_enabled(device))) {
2301 cqr->status = DASD_CQR_FAILED;
2302 cqr->intrc = -ENOLINK;
2303 continue;
2304 }
2305 /*
2306 * Don't try to start requests if device is in
2307 * offline processing, it might wait forever
2308 */
2309 if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
2310 cqr->status = DASD_CQR_FAILED;
2311 cqr->intrc = -ENODEV;
2312 continue;
2313 }
2314 /*
2315 * Don't try to start requests if device is stopped
2316 * except path verification requests
2317 */
2318 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
2319 if (interruptible) {
2320 rc = wait_event_interruptible(
2321 generic_waitq, !(device->stopped));
2322 if (rc == -ERESTARTSYS) {
2323 cqr->status = DASD_CQR_FAILED;
2324 maincqr->intrc = rc;
2325 continue;
2326 }
2327 } else
2328 wait_event(generic_waitq, !(device->stopped));
2329 }
2330 if (!cqr->callback)
2331 cqr->callback = dasd_wakeup_cb;
2332
2333 cqr->callback_data = DASD_SLEEPON_START_TAG;
2334 dasd_add_request_tail(cqr);
2335 if (interruptible) {
2336 rc = wait_event_interruptible(
2337 generic_waitq, _wait_for_wakeup(cqr));
2338 if (rc == -ERESTARTSYS) {
2339 dasd_cancel_req(cqr);
2340 /* wait (non-interruptible) for final status */
2341 wait_event(generic_waitq,
2342 _wait_for_wakeup(cqr));
2343 cqr->status = DASD_CQR_FAILED;
2344 maincqr->intrc = rc;
2345 continue;
2346 }
2347 } else
2348 wait_event(generic_waitq, _wait_for_wakeup(cqr));
2349 }
2350
2351 maincqr->endclk = get_tod_clock();
2352 if ((maincqr->status != DASD_CQR_DONE) &&
2353 (maincqr->intrc != -ERESTARTSYS))
2354 dasd_log_sense(maincqr, &maincqr->irb);
2355 if (maincqr->status == DASD_CQR_DONE)
2356 rc = 0;
2357 else if (maincqr->intrc)
2358 rc = maincqr->intrc;
2359 else
2360 rc = -EIO;
2361 return rc;
2362 }
2363
2364 static inline int _wait_for_wakeup_queue(struct list_head *ccw_queue)
2365 {
2366 struct dasd_ccw_req *cqr;
2367
2368 list_for_each_entry(cqr, ccw_queue, blocklist) {
2369 if (cqr->callback_data != DASD_SLEEPON_END_TAG)
2370 return 0;
2371 }
2372
2373 return 1;
2374 }
2375
2376 static int _dasd_sleep_on_queue(struct list_head *ccw_queue, int interruptible)
2377 {
2378 struct dasd_device *device;
2379 struct dasd_ccw_req *cqr, *n;
2380 u8 *sense = NULL;
2381 int rc;
2382
2383 retry:
2384 list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
2385 device = cqr->startdev;
2386 if (cqr->status != DASD_CQR_FILLED) /*could be failed*/
2387 continue;
2388
2389 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2390 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2391 cqr->status = DASD_CQR_FAILED;
2392 cqr->intrc = -EPERM;
2393 continue;
2394 }
2395 /*Non-temporary stop condition will trigger fail fast*/
2396 if (device->stopped & ~DASD_STOPPED_PENDING &&
2397 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2398 !dasd_eer_enabled(device)) {
2399 cqr->status = DASD_CQR_FAILED;
2400 cqr->intrc = -EAGAIN;
2401 continue;
2402 }
2403
2404 /*Don't try to start requests if device is stopped*/
2405 if (interruptible) {
2406 rc = wait_event_interruptible(
2407 generic_waitq, !device->stopped);
2408 if (rc == -ERESTARTSYS) {
2409 cqr->status = DASD_CQR_FAILED;
2410 cqr->intrc = rc;
2411 continue;
2412 }
2413 } else
2414 wait_event(generic_waitq, !(device->stopped));
2415
2416 if (!cqr->callback)
2417 cqr->callback = dasd_wakeup_cb;
2418 cqr->callback_data = DASD_SLEEPON_START_TAG;
2419 dasd_add_request_tail(cqr);
2420 }
2421
2422 wait_event(generic_waitq, _wait_for_wakeup_queue(ccw_queue));
2423
2424 rc = 0;
2425 list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
2426 /*
2427 * In some cases the 'File Protected' or 'Incorrect Length'
2428 * error might be expected and error recovery would be
2429 * unnecessary in these cases. Check if the according suppress
2430 * bit is set.
2431 */
2432 sense = dasd_get_sense(&cqr->irb);
2433 if (sense && sense[1] & SNS1_FILE_PROTECTED &&
2434 test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags))
2435 continue;
2436 if (scsw_cstat(&cqr->irb.scsw) == 0x40 &&
2437 test_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags))
2438 continue;
2439
2440 /*
2441 * for alias devices simplify error recovery and
2442 * return to upper layer
2443 * do not skip ERP requests
2444 */
2445 if (cqr->startdev != cqr->basedev && !cqr->refers &&
2446 (cqr->status == DASD_CQR_TERMINATED ||
2447 cqr->status == DASD_CQR_NEED_ERP))
2448 return -EAGAIN;
2449
2450 /* normal recovery for basedev IO */
2451 if (__dasd_sleep_on_erp(cqr))
2452 /* handle erp first */
2453 goto retry;
2454 }
2455
2456 return 0;
2457 }
2458
2459 /*
2460 * Queue a request to the tail of the device ccw_queue and wait for
2461 * it's completion.
2462 */
2463 int dasd_sleep_on(struct dasd_ccw_req *cqr)
2464 {
2465 return _dasd_sleep_on(cqr, 0);
2466 }
2467 EXPORT_SYMBOL(dasd_sleep_on);
2468
2469 /*
2470 * Start requests from a ccw_queue and wait for their completion.
2471 */
2472 int dasd_sleep_on_queue(struct list_head *ccw_queue)
2473 {
2474 return _dasd_sleep_on_queue(ccw_queue, 0);
2475 }
2476 EXPORT_SYMBOL(dasd_sleep_on_queue);
2477
2478 /*
2479 * Queue a request to the tail of the device ccw_queue and wait
2480 * interruptible for it's completion.
2481 */
2482 int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
2483 {
2484 return _dasd_sleep_on(cqr, 1);
2485 }
2486 EXPORT_SYMBOL(dasd_sleep_on_interruptible);
2487
2488 /*
2489 * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
2490 * for eckd devices) the currently running request has to be terminated
2491 * and be put back to status queued, before the special request is added
2492 * to the head of the queue. Then the special request is waited on normally.
2493 */
2494 static inline int _dasd_term_running_cqr(struct dasd_device *device)
2495 {
2496 struct dasd_ccw_req *cqr;
2497 int rc;
2498
2499 if (list_empty(&device->ccw_queue))
2500 return 0;
2501 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2502 rc = device->discipline->term_IO(cqr);
2503 if (!rc)
2504 /*
2505 * CQR terminated because a more important request is pending.
2506 * Undo decreasing of retry counter because this is
2507 * not an error case.
2508 */
2509 cqr->retries++;
2510 return rc;
2511 }
2512
2513 int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
2514 {
2515 struct dasd_device *device;
2516 int rc;
2517
2518 device = cqr->startdev;
2519 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2520 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2521 cqr->status = DASD_CQR_FAILED;
2522 cqr->intrc = -EPERM;
2523 return -EIO;
2524 }
2525 spin_lock_irq(get_ccwdev_lock(device->cdev));
2526 rc = _dasd_term_running_cqr(device);
2527 if (rc) {
2528 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2529 return rc;
2530 }
2531 cqr->callback = dasd_wakeup_cb;
2532 cqr->callback_data = DASD_SLEEPON_START_TAG;
2533 cqr->status = DASD_CQR_QUEUED;
2534 /*
2535 * add new request as second
2536 * first the terminated cqr needs to be finished
2537 */
2538 list_add(&cqr->devlist, device->ccw_queue.next);
2539
2540 /* let the bh start the request to keep them in order */
2541 dasd_schedule_device_bh(device);
2542
2543 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2544
2545 wait_event(generic_waitq, _wait_for_wakeup(cqr));
2546
2547 if (cqr->status == DASD_CQR_DONE)
2548 rc = 0;
2549 else if (cqr->intrc)
2550 rc = cqr->intrc;
2551 else
2552 rc = -EIO;
2553
2554 /* kick tasklets */
2555 dasd_schedule_device_bh(device);
2556 if (device->block)
2557 dasd_schedule_block_bh(device->block);
2558
2559 return rc;
2560 }
2561 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
2562
2563 /*
2564 * Cancels a request that was started with dasd_sleep_on_req.
2565 * This is useful to timeout requests. The request will be
2566 * terminated if it is currently in i/o.
2567 * Returns 0 if request termination was successful
2568 * negative error code if termination failed
2569 * Cancellation of a request is an asynchronous operation! The calling
2570 * function has to wait until the request is properly returned via callback.
2571 */
2572 int dasd_cancel_req(struct dasd_ccw_req *cqr)
2573 {
2574 struct dasd_device *device = cqr->startdev;
2575 unsigned long flags;
2576 int rc;
2577
2578 rc = 0;
2579 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2580 switch (cqr->status) {
2581 case DASD_CQR_QUEUED:
2582 /* request was not started - just set to cleared */
2583 cqr->status = DASD_CQR_CLEARED;
2584 if (cqr->callback_data == DASD_SLEEPON_START_TAG)
2585 cqr->callback_data = DASD_SLEEPON_END_TAG;
2586 break;
2587 case DASD_CQR_IN_IO:
2588 /* request in IO - terminate IO and release again */
2589 rc = device->discipline->term_IO(cqr);
2590 if (rc) {
2591 dev_err(&device->cdev->dev,
2592 "Cancelling request %p failed with rc=%d\n",
2593 cqr, rc);
2594 } else {
2595 cqr->stopclk = get_tod_clock();
2596 }
2597 break;
2598 default: /* already finished or clear pending - do nothing */
2599 break;
2600 }
2601 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2602 dasd_schedule_device_bh(device);
2603 return rc;
2604 }
2605 EXPORT_SYMBOL(dasd_cancel_req);
2606
2607 /*
2608 * SECTION: Operations of the dasd_block layer.
2609 */
2610
2611 /*
2612 * Timeout function for dasd_block. This is used when the block layer
2613 * is waiting for something that may not come reliably, (e.g. a state
2614 * change interrupt)
2615 */
2616 static void dasd_block_timeout(struct timer_list *t)
2617 {
2618 unsigned long flags;
2619 struct dasd_block *block;
2620
2621 block = from_timer(block, t, timer);
2622 spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
2623 /* re-activate request queue */
2624 dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING);
2625 spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
2626 dasd_schedule_block_bh(block);
2627 blk_mq_run_hw_queues(block->request_queue, true);
2628 }
2629
2630 /*
2631 * Setup timeout for a dasd_block in jiffies.
2632 */
2633 void dasd_block_set_timer(struct dasd_block *block, int expires)
2634 {
2635 if (expires == 0)
2636 del_timer(&block->timer);
2637 else
2638 mod_timer(&block->timer, jiffies + expires);
2639 }
2640 EXPORT_SYMBOL(dasd_block_set_timer);
2641
2642 /*
2643 * Clear timeout for a dasd_block.
2644 */
2645 void dasd_block_clear_timer(struct dasd_block *block)
2646 {
2647 del_timer(&block->timer);
2648 }
2649 EXPORT_SYMBOL(dasd_block_clear_timer);
2650
2651 /*
2652 * Process finished error recovery ccw.
2653 */
2654 static void __dasd_process_erp(struct dasd_device *device,
2655 struct dasd_ccw_req *cqr)
2656 {
2657 dasd_erp_fn_t erp_fn;
2658
2659 if (cqr->status == DASD_CQR_DONE)
2660 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
2661 else
2662 dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
2663 erp_fn = device->discipline->erp_postaction(cqr);
2664 erp_fn(cqr);
2665 }
2666
2667 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
2668 {
2669 struct request *req;
2670 blk_status_t error = BLK_STS_OK;
2671 int status;
2672
2673 req = (struct request *) cqr->callback_data;
2674 dasd_profile_end(cqr->block, cqr, req);
2675
2676 status = cqr->block->base->discipline->free_cp(cqr, req);
2677 if (status < 0)
2678 error = errno_to_blk_status(status);
2679 else if (status == 0) {
2680 switch (cqr->intrc) {
2681 case -EPERM:
2682 error = BLK_STS_NEXUS;
2683 break;
2684 case -ENOLINK:
2685 error = BLK_STS_TRANSPORT;
2686 break;
2687 case -ETIMEDOUT:
2688 error = BLK_STS_TIMEOUT;
2689 break;
2690 default:
2691 error = BLK_STS_IOERR;
2692 break;
2693 }
2694 }
2695
2696 /*
2697 * We need to take care for ETIMEDOUT errors here since the
2698 * complete callback does not get called in this case.
2699 * Take care of all errors here and avoid additional code to
2700 * transfer the error value to the complete callback.
2701 */
2702 if (error) {
2703 blk_mq_end_request(req, error);
2704 blk_mq_run_hw_queues(req->q, true);
2705 } else {
2706 blk_mq_complete_request(req);
2707 }
2708 }
2709
2710 /*
2711 * Process ccw request queue.
2712 */
2713 static void __dasd_process_block_ccw_queue(struct dasd_block *block,
2714 struct list_head *final_queue)
2715 {
2716 struct list_head *l, *n;
2717 struct dasd_ccw_req *cqr;
2718 dasd_erp_fn_t erp_fn;
2719 unsigned long flags;
2720 struct dasd_device *base = block->base;
2721
2722 restart:
2723 /* Process request with final status. */
2724 list_for_each_safe(l, n, &block->ccw_queue) {
2725 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2726 if (cqr->status != DASD_CQR_DONE &&
2727 cqr->status != DASD_CQR_FAILED &&
2728 cqr->status != DASD_CQR_NEED_ERP &&
2729 cqr->status != DASD_CQR_TERMINATED)
2730 continue;
2731
2732 if (cqr->status == DASD_CQR_TERMINATED) {
2733 base->discipline->handle_terminated_request(cqr);
2734 goto restart;
2735 }
2736
2737 /* Process requests that may be recovered */
2738 if (cqr->status == DASD_CQR_NEED_ERP) {
2739 erp_fn = base->discipline->erp_action(cqr);
2740 if (IS_ERR(erp_fn(cqr)))
2741 continue;
2742 goto restart;
2743 }
2744
2745 /* log sense for fatal error */
2746 if (cqr->status == DASD_CQR_FAILED) {
2747 dasd_log_sense(cqr, &cqr->irb);
2748 }
2749
2750 /* First of all call extended error reporting. */
2751 if (dasd_eer_enabled(base) &&
2752 cqr->status == DASD_CQR_FAILED) {
2753 dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
2754
2755 /* restart request */
2756 cqr->status = DASD_CQR_FILLED;
2757 cqr->retries = 255;
2758 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
2759 dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
2760 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
2761 flags);
2762 goto restart;
2763 }
2764
2765 /* Process finished ERP request. */
2766 if (cqr->refers) {
2767 __dasd_process_erp(base, cqr);
2768 goto restart;
2769 }
2770
2771 /* Rechain finished requests to final queue */
2772 cqr->endclk = get_tod_clock();
2773 list_move_tail(&cqr->blocklist, final_queue);
2774 }
2775 }
2776
2777 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
2778 {
2779 dasd_schedule_block_bh(cqr->block);
2780 }
2781
2782 static void __dasd_block_start_head(struct dasd_block *block)
2783 {
2784 struct dasd_ccw_req *cqr;
2785
2786 if (list_empty(&block->ccw_queue))
2787 return;
2788 /* We allways begin with the first requests on the queue, as some
2789 * of previously started requests have to be enqueued on a
2790 * dasd_device again for error recovery.
2791 */
2792 list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
2793 if (cqr->status != DASD_CQR_FILLED)
2794 continue;
2795 if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) &&
2796 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2797 cqr->status = DASD_CQR_FAILED;
2798 cqr->intrc = -EPERM;
2799 dasd_schedule_block_bh(block);
2800 continue;
2801 }
2802 /* Non-temporary stop condition will trigger fail fast */
2803 if (block->base->stopped & ~DASD_STOPPED_PENDING &&
2804 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2805 (!dasd_eer_enabled(block->base))) {
2806 cqr->status = DASD_CQR_FAILED;
2807 cqr->intrc = -ENOLINK;
2808 dasd_schedule_block_bh(block);
2809 continue;
2810 }
2811 /* Don't try to start requests if device is stopped */
2812 if (block->base->stopped)
2813 return;
2814
2815 /* just a fail safe check, should not happen */
2816 if (!cqr->startdev)
2817 cqr->startdev = block->base;
2818
2819 /* make sure that the requests we submit find their way back */
2820 cqr->callback = dasd_return_cqr_cb;
2821
2822 dasd_add_request_tail(cqr);
2823 }
2824 }
2825
2826 /*
2827 * Central dasd_block layer routine. Takes requests from the generic
2828 * block layer request queue, creates ccw requests, enqueues them on
2829 * a dasd_device and processes ccw requests that have been returned.
2830 */
2831 static void dasd_block_tasklet(struct dasd_block *block)
2832 {
2833 struct list_head final_queue;
2834 struct list_head *l, *n;
2835 struct dasd_ccw_req *cqr;
2836 struct dasd_queue *dq;
2837
2838 atomic_set(&block->tasklet_scheduled, 0);
2839 INIT_LIST_HEAD(&final_queue);
2840 spin_lock_irq(&block->queue_lock);
2841 /* Finish off requests on ccw queue */
2842 __dasd_process_block_ccw_queue(block, &final_queue);
2843 spin_unlock_irq(&block->queue_lock);
2844
2845 /* Now call the callback function of requests with final status */
2846 list_for_each_safe(l, n, &final_queue) {
2847 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2848 dq = cqr->dq;
2849 spin_lock_irq(&dq->lock);
2850 list_del_init(&cqr->blocklist);
2851 __dasd_cleanup_cqr(cqr);
2852 spin_unlock_irq(&dq->lock);
2853 }
2854
2855 spin_lock_irq(&block->queue_lock);
2856 /* Now check if the head of the ccw queue needs to be started. */
2857 __dasd_block_start_head(block);
2858 spin_unlock_irq(&block->queue_lock);
2859
2860 if (waitqueue_active(&shutdown_waitq))
2861 wake_up(&shutdown_waitq);
2862 dasd_put_device(block->base);
2863 }
2864
2865 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
2866 {
2867 wake_up(&dasd_flush_wq);
2868 }
2869
2870 /*
2871 * Requeue a request back to the block request queue
2872 * only works for block requests
2873 */
2874 static int _dasd_requeue_request(struct dasd_ccw_req *cqr)
2875 {
2876 struct dasd_block *block = cqr->block;
2877 struct request *req;
2878
2879 if (!block)
2880 return -EINVAL;
2881 spin_lock_irq(&cqr->dq->lock);
2882 req = (struct request *) cqr->callback_data;
2883 blk_mq_requeue_request(req, false);
2884 spin_unlock_irq(&cqr->dq->lock);
2885
2886 return 0;
2887 }
2888
2889 /*
2890 * Go through all request on the dasd_block request queue, cancel them
2891 * on the respective dasd_device, and return them to the generic
2892 * block layer.
2893 */
2894 static int dasd_flush_block_queue(struct dasd_block *block)
2895 {
2896 struct dasd_ccw_req *cqr, *n;
2897 int rc, i;
2898 struct list_head flush_queue;
2899 unsigned long flags;
2900
2901 INIT_LIST_HEAD(&flush_queue);
2902 spin_lock_bh(&block->queue_lock);
2903 rc = 0;
2904 restart:
2905 list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
2906 /* if this request currently owned by a dasd_device cancel it */
2907 if (cqr->status >= DASD_CQR_QUEUED)
2908 rc = dasd_cancel_req(cqr);
2909 if (rc < 0)
2910 break;
2911 /* Rechain request (including erp chain) so it won't be
2912 * touched by the dasd_block_tasklet anymore.
2913 * Replace the callback so we notice when the request
2914 * is returned from the dasd_device layer.
2915 */
2916 cqr->callback = _dasd_wake_block_flush_cb;
2917 for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
2918 list_move_tail(&cqr->blocklist, &flush_queue);
2919 if (i > 1)
2920 /* moved more than one request - need to restart */
2921 goto restart;
2922 }
2923 spin_unlock_bh(&block->queue_lock);
2924 /* Now call the callback function of flushed requests */
2925 restart_cb:
2926 list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
2927 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
2928 /* Process finished ERP request. */
2929 if (cqr->refers) {
2930 spin_lock_bh(&block->queue_lock);
2931 __dasd_process_erp(block->base, cqr);
2932 spin_unlock_bh(&block->queue_lock);
2933 /* restart list_for_xx loop since dasd_process_erp
2934 * might remove multiple elements */
2935 goto restart_cb;
2936 }
2937 /* call the callback function */
2938 spin_lock_irqsave(&cqr->dq->lock, flags);
2939 cqr->endclk = get_tod_clock();
2940 list_del_init(&cqr->blocklist);
2941 __dasd_cleanup_cqr(cqr);
2942 spin_unlock_irqrestore(&cqr->dq->lock, flags);
2943 }
2944 return rc;
2945 }
2946
2947 /*
2948 * Schedules a call to dasd_tasklet over the device tasklet.
2949 */
2950 void dasd_schedule_block_bh(struct dasd_block *block)
2951 {
2952 /* Protect against rescheduling. */
2953 if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
2954 return;
2955 /* life cycle of block is bound to it's base device */
2956 dasd_get_device(block->base);
2957 tasklet_hi_schedule(&block->tasklet);
2958 }
2959 EXPORT_SYMBOL(dasd_schedule_block_bh);
2960
2961
2962 /*
2963 * SECTION: external block device operations
2964 * (request queue handling, open, release, etc.)
2965 */
2966
2967 /*
2968 * Dasd request queue function. Called from ll_rw_blk.c
2969 */
2970 static blk_status_t do_dasd_request(struct blk_mq_hw_ctx *hctx,
2971 const struct blk_mq_queue_data *qd)
2972 {
2973 struct dasd_block *block = hctx->queue->queuedata;
2974 struct dasd_queue *dq = hctx->driver_data;
2975 struct request *req = qd->rq;
2976 struct dasd_device *basedev;
2977 struct dasd_ccw_req *cqr;
2978 blk_status_t rc = BLK_STS_OK;
2979
2980 basedev = block->base;
2981 spin_lock_irq(&dq->lock);
2982 if (basedev->state < DASD_STATE_READY) {
2983 DBF_DEV_EVENT(DBF_ERR, basedev,
2984 "device not ready for request %p", req);
2985 rc = BLK_STS_IOERR;
2986 goto out;
2987 }
2988
2989 /*
2990 * if device is stopped do not fetch new requests
2991 * except failfast is active which will let requests fail
2992 * immediately in __dasd_block_start_head()
2993 */
2994 if (basedev->stopped && !(basedev->features & DASD_FEATURE_FAILFAST)) {
2995 DBF_DEV_EVENT(DBF_ERR, basedev,
2996 "device stopped request %p", req);
2997 rc = BLK_STS_RESOURCE;
2998 goto out;
2999 }
3000
3001 if (basedev->features & DASD_FEATURE_READONLY &&
3002 rq_data_dir(req) == WRITE) {
3003 DBF_DEV_EVENT(DBF_ERR, basedev,
3004 "Rejecting write request %p", req);
3005 rc = BLK_STS_IOERR;
3006 goto out;
3007 }
3008
3009 if (test_bit(DASD_FLAG_ABORTALL, &basedev->flags) &&
3010 (basedev->features & DASD_FEATURE_FAILFAST ||
3011 blk_noretry_request(req))) {
3012 DBF_DEV_EVENT(DBF_ERR, basedev,
3013 "Rejecting failfast request %p", req);
3014 rc = BLK_STS_IOERR;
3015 goto out;
3016 }
3017
3018 cqr = basedev->discipline->build_cp(basedev, block, req);
3019 if (IS_ERR(cqr)) {
3020 if (PTR_ERR(cqr) == -EBUSY ||
3021 PTR_ERR(cqr) == -ENOMEM ||
3022 PTR_ERR(cqr) == -EAGAIN) {
3023 rc = BLK_STS_RESOURCE;
3024 goto out;
3025 }
3026 DBF_DEV_EVENT(DBF_ERR, basedev,
3027 "CCW creation failed (rc=%ld) on request %p",
3028 PTR_ERR(cqr), req);
3029 rc = BLK_STS_IOERR;
3030 goto out;
3031 }
3032 /*
3033 * Note: callback is set to dasd_return_cqr_cb in
3034 * __dasd_block_start_head to cover erp requests as well
3035 */
3036 cqr->callback_data = req;
3037 cqr->status = DASD_CQR_FILLED;
3038 cqr->dq = dq;
3039 req->completion_data = cqr;
3040 blk_mq_start_request(req);
3041 spin_lock(&block->queue_lock);
3042 list_add_tail(&cqr->blocklist, &block->ccw_queue);
3043 INIT_LIST_HEAD(&cqr->devlist);
3044 dasd_profile_start(block, cqr, req);
3045 dasd_schedule_block_bh(block);
3046 spin_unlock(&block->queue_lock);
3047
3048 out:
3049 spin_unlock_irq(&dq->lock);
3050 return rc;
3051 }
3052
3053 /*
3054 * Block timeout callback, called from the block layer
3055 *
3056 * Return values:
3057 * BLK_EH_RESET_TIMER if the request should be left running
3058 * BLK_EH_NOT_HANDLED if the request is handled or terminated
3059 * by the driver.
3060 */
3061 enum blk_eh_timer_return dasd_times_out(struct request *req, bool reserved)
3062 {
3063 struct dasd_ccw_req *cqr = req->completion_data;
3064 struct dasd_block *block = req->q->queuedata;
3065 struct dasd_device *device;
3066 unsigned long flags;
3067 int rc = 0;
3068
3069 if (!cqr)
3070 return BLK_EH_NOT_HANDLED;
3071
3072 spin_lock_irqsave(&cqr->dq->lock, flags);
3073 device = cqr->startdev ? cqr->startdev : block->base;
3074 if (!device->blk_timeout) {
3075 spin_unlock_irqrestore(&cqr->dq->lock, flags);
3076 return BLK_EH_RESET_TIMER;
3077 }
3078 DBF_DEV_EVENT(DBF_WARNING, device,
3079 " dasd_times_out cqr %p status %x",
3080 cqr, cqr->status);
3081
3082 spin_lock(&block->queue_lock);
3083 spin_lock(get_ccwdev_lock(device->cdev));
3084 cqr->retries = -1;
3085 cqr->intrc = -ETIMEDOUT;
3086 if (cqr->status >= DASD_CQR_QUEUED) {
3087 spin_unlock(get_ccwdev_lock(device->cdev));
3088 rc = dasd_cancel_req(cqr);
3089 } else if (cqr->status == DASD_CQR_FILLED ||
3090 cqr->status == DASD_CQR_NEED_ERP) {
3091 cqr->status = DASD_CQR_TERMINATED;
3092 spin_unlock(get_ccwdev_lock(device->cdev));
3093 } else if (cqr->status == DASD_CQR_IN_ERP) {
3094 struct dasd_ccw_req *searchcqr, *nextcqr, *tmpcqr;
3095
3096 list_for_each_entry_safe(searchcqr, nextcqr,
3097 &block->ccw_queue, blocklist) {
3098 tmpcqr = searchcqr;
3099 while (tmpcqr->refers)
3100 tmpcqr = tmpcqr->refers;
3101 if (tmpcqr != cqr)
3102 continue;
3103 /* searchcqr is an ERP request for cqr */
3104 searchcqr->retries = -1;
3105 searchcqr->intrc = -ETIMEDOUT;
3106 if (searchcqr->status >= DASD_CQR_QUEUED) {
3107 spin_unlock(get_ccwdev_lock(device->cdev));
3108 rc = dasd_cancel_req(searchcqr);
3109 spin_lock(get_ccwdev_lock(device->cdev));
3110 } else if ((searchcqr->status == DASD_CQR_FILLED) ||
3111 (searchcqr->status == DASD_CQR_NEED_ERP)) {
3112 searchcqr->status = DASD_CQR_TERMINATED;
3113 rc = 0;
3114 } else if (searchcqr->status == DASD_CQR_IN_ERP) {
3115 /*
3116 * Shouldn't happen; most recent ERP
3117 * request is at the front of queue
3118 */
3119 continue;
3120 }
3121 break;
3122 }
3123 spin_unlock(get_ccwdev_lock(device->cdev));
3124 }
3125 dasd_schedule_block_bh(block);
3126 spin_unlock(&block->queue_lock);
3127 spin_unlock_irqrestore(&cqr->dq->lock, flags);
3128
3129 return rc ? BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED;
3130 }
3131
3132 static int dasd_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
3133 unsigned int idx)
3134 {
3135 struct dasd_queue *dq = kzalloc(sizeof(*dq), GFP_KERNEL);
3136
3137 if (!dq)
3138 return -ENOMEM;
3139
3140 spin_lock_init(&dq->lock);
3141 hctx->driver_data = dq;
3142
3143 return 0;
3144 }
3145
3146 static void dasd_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int idx)
3147 {
3148 kfree(hctx->driver_data);
3149 hctx->driver_data = NULL;
3150 }
3151
3152 static void dasd_request_done(struct request *req)
3153 {
3154 blk_mq_end_request(req, 0);
3155 blk_mq_run_hw_queues(req->q, true);
3156 }
3157
3158 static struct blk_mq_ops dasd_mq_ops = {
3159 .queue_rq = do_dasd_request,
3160 .complete = dasd_request_done,
3161 .timeout = dasd_times_out,
3162 .init_hctx = dasd_init_hctx,
3163 .exit_hctx = dasd_exit_hctx,
3164 };
3165
3166 /*
3167 * Allocate and initialize request queue and default I/O scheduler.
3168 */
3169 static int dasd_alloc_queue(struct dasd_block *block)
3170 {
3171 int rc;
3172
3173 block->tag_set.ops = &dasd_mq_ops;
3174 block->tag_set.nr_hw_queues = DASD_NR_HW_QUEUES;
3175 block->tag_set.queue_depth = DASD_MAX_LCU_DEV * DASD_REQ_PER_DEV;
3176 block->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
3177
3178 rc = blk_mq_alloc_tag_set(&block->tag_set);
3179 if (rc)
3180 return rc;
3181
3182 block->request_queue = blk_mq_init_queue(&block->tag_set);
3183 if (IS_ERR(block->request_queue))
3184 return PTR_ERR(block->request_queue);
3185
3186 block->request_queue->queuedata = block;
3187
3188 return 0;
3189 }
3190
3191 /*
3192 * Allocate and initialize request queue.
3193 */
3194 static void dasd_setup_queue(struct dasd_block *block)
3195 {
3196 unsigned int logical_block_size = block->bp_block;
3197 struct request_queue *q = block->request_queue;
3198 unsigned int max_bytes, max_discard_sectors;
3199 int max;
3200
3201 if (block->base->features & DASD_FEATURE_USERAW) {
3202 /*
3203 * the max_blocks value for raw_track access is 256
3204 * it is higher than the native ECKD value because we
3205 * only need one ccw per track
3206 * so the max_hw_sectors are
3207 * 2048 x 512B = 1024kB = 16 tracks
3208 */
3209 max = 2048;
3210 } else {
3211 max = block->base->discipline->max_blocks << block->s2b_shift;
3212 }
3213 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
3214 q->limits.max_dev_sectors = max;
3215 blk_queue_logical_block_size(q, logical_block_size);
3216 blk_queue_max_hw_sectors(q, max);
3217 blk_queue_max_segments(q, USHRT_MAX);
3218 /* with page sized segments we can translate each segement into
3219 * one idaw/tidaw
3220 */
3221 blk_queue_max_segment_size(q, PAGE_SIZE);
3222 blk_queue_segment_boundary(q, PAGE_SIZE - 1);
3223
3224 /* Only activate blocklayer discard support for devices that support it */
3225 if (block->base->features & DASD_FEATURE_DISCARD) {
3226 q->limits.discard_granularity = logical_block_size;
3227 q->limits.discard_alignment = PAGE_SIZE;
3228
3229 /* Calculate max_discard_sectors and make it PAGE aligned */
3230 max_bytes = USHRT_MAX * logical_block_size;
3231 max_bytes = ALIGN(max_bytes, PAGE_SIZE) - PAGE_SIZE;
3232 max_discard_sectors = max_bytes / logical_block_size;
3233
3234 blk_queue_max_discard_sectors(q, max_discard_sectors);
3235 blk_queue_max_write_zeroes_sectors(q, max_discard_sectors);
3236 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
3237 }
3238 }
3239
3240 /*
3241 * Deactivate and free request queue.
3242 */
3243 static void dasd_free_queue(struct dasd_block *block)
3244 {
3245 if (block->request_queue) {
3246 blk_cleanup_queue(block->request_queue);
3247 blk_mq_free_tag_set(&block->tag_set);
3248 block->request_queue = NULL;
3249 }
3250 }
3251
3252 static int dasd_open(struct block_device *bdev, fmode_t mode)
3253 {
3254 struct dasd_device *base;
3255 int rc;
3256
3257 base = dasd_device_from_gendisk(bdev->bd_disk);
3258 if (!base)
3259 return -ENODEV;
3260
3261 atomic_inc(&base->block->open_count);
3262 if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
3263 rc = -ENODEV;
3264 goto unlock;
3265 }
3266
3267 if (!try_module_get(base->discipline->owner)) {
3268 rc = -EINVAL;
3269 goto unlock;
3270 }
3271
3272 if (dasd_probeonly) {
3273 dev_info(&base->cdev->dev,
3274 "Accessing the DASD failed because it is in "
3275 "probeonly mode\n");
3276 rc = -EPERM;
3277 goto out;
3278 }
3279
3280 if (base->state <= DASD_STATE_BASIC) {
3281 DBF_DEV_EVENT(DBF_ERR, base, " %s",
3282 " Cannot open unrecognized device");
3283 rc = -ENODEV;
3284 goto out;
3285 }
3286
3287 if ((mode & FMODE_WRITE) &&
3288 (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) ||
3289 (base->features & DASD_FEATURE_READONLY))) {
3290 rc = -EROFS;
3291 goto out;
3292 }
3293
3294 dasd_put_device(base);
3295 return 0;
3296
3297 out:
3298 module_put(base->discipline->owner);
3299 unlock:
3300 atomic_dec(&base->block->open_count);
3301 dasd_put_device(base);
3302 return rc;
3303 }
3304
3305 static void dasd_release(struct gendisk *disk, fmode_t mode)
3306 {
3307 struct dasd_device *base = dasd_device_from_gendisk(disk);
3308 if (base) {
3309 atomic_dec(&base->block->open_count);
3310 module_put(base->discipline->owner);
3311 dasd_put_device(base);
3312 }
3313 }
3314
3315 /*
3316 * Return disk geometry.
3317 */
3318 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
3319 {
3320 struct dasd_device *base;
3321
3322 base = dasd_device_from_gendisk(bdev->bd_disk);
3323 if (!base)
3324 return -ENODEV;
3325
3326 if (!base->discipline ||
3327 !base->discipline->fill_geometry) {
3328 dasd_put_device(base);
3329 return -EINVAL;
3330 }
3331 base->discipline->fill_geometry(base->block, geo);
3332 geo->start = get_start_sect(bdev) >> base->block->s2b_shift;
3333 dasd_put_device(base);
3334 return 0;
3335 }
3336
3337 const struct block_device_operations
3338 dasd_device_operations = {
3339 .owner = THIS_MODULE,
3340 .open = dasd_open,
3341 .release = dasd_release,
3342 .ioctl = dasd_ioctl,
3343 .compat_ioctl = dasd_ioctl,
3344 .getgeo = dasd_getgeo,
3345 };
3346
3347 /*******************************************************************************
3348 * end of block device operations
3349 */
3350
3351 static void
3352 dasd_exit(void)
3353 {
3354 #ifdef CONFIG_PROC_FS
3355 dasd_proc_exit();
3356 #endif
3357 dasd_eer_exit();
3358 if (dasd_page_cache != NULL) {
3359 kmem_cache_destroy(dasd_page_cache);
3360 dasd_page_cache = NULL;
3361 }
3362 dasd_gendisk_exit();
3363 dasd_devmap_exit();
3364 if (dasd_debug_area != NULL) {
3365 debug_unregister(dasd_debug_area);
3366 dasd_debug_area = NULL;
3367 }
3368 dasd_statistics_removeroot();
3369 }
3370
3371 /*
3372 * SECTION: common functions for ccw_driver use
3373 */
3374
3375 /*
3376 * Is the device read-only?
3377 * Note that this function does not report the setting of the
3378 * readonly device attribute, but how it is configured in z/VM.
3379 */
3380 int dasd_device_is_ro(struct dasd_device *device)
3381 {
3382 struct ccw_dev_id dev_id;
3383 struct diag210 diag_data;
3384 int rc;
3385
3386 if (!MACHINE_IS_VM)
3387 return 0;
3388 ccw_device_get_id(device->cdev, &dev_id);
3389 memset(&diag_data, 0, sizeof(diag_data));
3390 diag_data.vrdcdvno = dev_id.devno;
3391 diag_data.vrdclen = sizeof(diag_data);
3392 rc = diag210(&diag_data);
3393 if (rc == 0 || rc == 2) {
3394 return diag_data.vrdcvfla & 0x80;
3395 } else {
3396 DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d",
3397 dev_id.devno, rc);
3398 return 0;
3399 }
3400 }
3401 EXPORT_SYMBOL_GPL(dasd_device_is_ro);
3402
3403 static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
3404 {
3405 struct ccw_device *cdev = data;
3406 int ret;
3407
3408 ret = ccw_device_set_online(cdev);
3409 if (ret)
3410 pr_warn("%s: Setting the DASD online failed with rc=%d\n",
3411 dev_name(&cdev->dev), ret);
3412 }
3413
3414 /*
3415 * Initial attempt at a probe function. this can be simplified once
3416 * the other detection code is gone.
3417 */
3418 int dasd_generic_probe(struct ccw_device *cdev,
3419 struct dasd_discipline *discipline)
3420 {
3421 int ret;
3422
3423 ret = dasd_add_sysfs_files(cdev);
3424 if (ret) {
3425 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s",
3426 "dasd_generic_probe: could not add "
3427 "sysfs entries");
3428 return ret;
3429 }
3430 cdev->handler = &dasd_int_handler;
3431
3432 /*
3433 * Automatically online either all dasd devices (dasd_autodetect)
3434 * or all devices specified with dasd= parameters during
3435 * initial probe.
3436 */
3437 if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
3438 (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
3439 async_schedule(dasd_generic_auto_online, cdev);
3440 return 0;
3441 }
3442 EXPORT_SYMBOL_GPL(dasd_generic_probe);
3443
3444 void dasd_generic_free_discipline(struct dasd_device *device)
3445 {
3446 /* Forget the discipline information. */
3447 if (device->discipline) {
3448 if (device->discipline->uncheck_device)
3449 device->discipline->uncheck_device(device);
3450 module_put(device->discipline->owner);
3451 device->discipline = NULL;
3452 }
3453 if (device->base_discipline) {
3454 module_put(device->base_discipline->owner);
3455 device->base_discipline = NULL;
3456 }
3457 }
3458 EXPORT_SYMBOL_GPL(dasd_generic_free_discipline);
3459
3460 /*
3461 * This will one day be called from a global not_oper handler.
3462 * It is also used by driver_unregister during module unload.
3463 */
3464 void dasd_generic_remove(struct ccw_device *cdev)
3465 {
3466 struct dasd_device *device;
3467 struct dasd_block *block;
3468
3469 cdev->handler = NULL;
3470
3471 device = dasd_device_from_cdev(cdev);
3472 if (IS_ERR(device)) {
3473 dasd_remove_sysfs_files(cdev);
3474 return;
3475 }
3476 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags) &&
3477 !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3478 /* Already doing offline processing */
3479 dasd_put_device(device);
3480 dasd_remove_sysfs_files(cdev);
3481 return;
3482 }
3483 /*
3484 * This device is removed unconditionally. Set offline
3485 * flag to prevent dasd_open from opening it while it is
3486 * no quite down yet.
3487 */
3488 dasd_set_target_state(device, DASD_STATE_NEW);
3489 /* dasd_delete_device destroys the device reference. */
3490 block = device->block;
3491 dasd_delete_device(device);
3492 /*
3493 * life cycle of block is bound to device, so delete it after
3494 * device was safely removed
3495 */
3496 if (block)
3497 dasd_free_block(block);
3498
3499 dasd_remove_sysfs_files(cdev);
3500 }
3501 EXPORT_SYMBOL_GPL(dasd_generic_remove);
3502
3503 /*
3504 * Activate a device. This is called from dasd_{eckd,fba}_probe() when either
3505 * the device is detected for the first time and is supposed to be used
3506 * or the user has started activation through sysfs.
3507 */
3508 int dasd_generic_set_online(struct ccw_device *cdev,
3509 struct dasd_discipline *base_discipline)
3510 {
3511 struct dasd_discipline *discipline;
3512 struct dasd_device *device;
3513 int rc;
3514
3515 /* first online clears initial online feature flag */
3516 dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
3517 device = dasd_create_device(cdev);
3518 if (IS_ERR(device))
3519 return PTR_ERR(device);
3520
3521 discipline = base_discipline;
3522 if (device->features & DASD_FEATURE_USEDIAG) {
3523 if (!dasd_diag_discipline_pointer) {
3524 /* Try to load the required module. */
3525 rc = request_module(DASD_DIAG_MOD);
3526 if (rc) {
3527 pr_warn("%s Setting the DASD online failed "
3528 "because the required module %s "
3529 "could not be loaded (rc=%d)\n",
3530 dev_name(&cdev->dev), DASD_DIAG_MOD,
3531 rc);
3532 dasd_delete_device(device);
3533 return -ENODEV;
3534 }
3535 }
3536 /* Module init could have failed, so check again here after
3537 * request_module(). */
3538 if (!dasd_diag_discipline_pointer) {
3539 pr_warn("%s Setting the DASD online failed because of missing DIAG discipline\n",
3540 dev_name(&cdev->dev));
3541 dasd_delete_device(device);
3542 return -ENODEV;
3543 }
3544 discipline = dasd_diag_discipline_pointer;
3545 }
3546 if (!try_module_get(base_discipline->owner)) {
3547 dasd_delete_device(device);
3548 return -EINVAL;
3549 }
3550 if (!try_module_get(discipline->owner)) {
3551 module_put(base_discipline->owner);
3552 dasd_delete_device(device);
3553 return -EINVAL;
3554 }
3555 device->base_discipline = base_discipline;
3556 device->discipline = discipline;
3557
3558 /* check_device will allocate block device if necessary */
3559 rc = discipline->check_device(device);
3560 if (rc) {
3561 pr_warn("%s Setting the DASD online with discipline %s failed with rc=%i\n",
3562 dev_name(&cdev->dev), discipline->name, rc);
3563 module_put(discipline->owner);
3564 module_put(base_discipline->owner);
3565 dasd_delete_device(device);
3566 return rc;
3567 }
3568
3569 dasd_set_target_state(device, DASD_STATE_ONLINE);
3570 if (device->state <= DASD_STATE_KNOWN) {
3571 pr_warn("%s Setting the DASD online failed because of a missing discipline\n",
3572 dev_name(&cdev->dev));
3573 rc = -ENODEV;
3574 dasd_set_target_state(device, DASD_STATE_NEW);
3575 if (device->block)
3576 dasd_free_block(device->block);
3577 dasd_delete_device(device);
3578 } else
3579 pr_debug("dasd_generic device %s found\n",
3580 dev_name(&cdev->dev));
3581
3582 wait_event(dasd_init_waitq, _wait_for_device(device));
3583
3584 dasd_put_device(device);
3585 return rc;
3586 }
3587 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
3588
3589 int dasd_generic_set_offline(struct ccw_device *cdev)
3590 {
3591 struct dasd_device *device;
3592 struct dasd_block *block;
3593 int max_count, open_count, rc;
3594 unsigned long flags;
3595
3596 rc = 0;
3597 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3598 device = dasd_device_from_cdev_locked(cdev);
3599 if (IS_ERR(device)) {
3600 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3601 return PTR_ERR(device);
3602 }
3603
3604 /*
3605 * We must make sure that this device is currently not in use.
3606 * The open_count is increased for every opener, that includes
3607 * the blkdev_get in dasd_scan_partitions. We are only interested
3608 * in the other openers.
3609 */
3610 if (device->block) {
3611 max_count = device->block->bdev ? 0 : -1;
3612 open_count = atomic_read(&device->block->open_count);
3613 if (open_count > max_count) {
3614 if (open_count > 0)
3615 pr_warn("%s: The DASD cannot be set offline with open count %i\n",
3616 dev_name(&cdev->dev), open_count);
3617 else
3618 pr_warn("%s: The DASD cannot be set offline while it is in use\n",
3619 dev_name(&cdev->dev));
3620 rc = -EBUSY;
3621 goto out_err;
3622 }
3623 }
3624
3625 /*
3626 * Test if the offline processing is already running and exit if so.
3627 * If a safe offline is being processed this could only be a normal
3628 * offline that should be able to overtake the safe offline and
3629 * cancel any I/O we do not want to wait for any longer
3630 */
3631 if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3632 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3633 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING,
3634 &device->flags);
3635 } else {
3636 rc = -EBUSY;
3637 goto out_err;
3638 }
3639 }
3640 set_bit(DASD_FLAG_OFFLINE, &device->flags);
3641
3642 /*
3643 * if safe_offline is called set safe_offline_running flag and
3644 * clear safe_offline so that a call to normal offline
3645 * can overrun safe_offline processing
3646 */
3647 if (test_and_clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags) &&
3648 !test_and_set_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3649 /* need to unlock here to wait for outstanding I/O */
3650 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3651 /*
3652 * If we want to set the device safe offline all IO operations
3653 * should be finished before continuing the offline process
3654 * so sync bdev first and then wait for our queues to become
3655 * empty
3656 */
3657 if (device->block) {
3658 rc = fsync_bdev(device->block->bdev);
3659 if (rc != 0)
3660 goto interrupted;
3661 }
3662 dasd_schedule_device_bh(device);
3663 rc = wait_event_interruptible(shutdown_waitq,
3664 _wait_for_empty_queues(device));
3665 if (rc != 0)
3666 goto interrupted;
3667
3668 /*
3669 * check if a normal offline process overtook the offline
3670 * processing in this case simply do nothing beside returning
3671 * that we got interrupted
3672 * otherwise mark safe offline as not running any longer and
3673 * continue with normal offline
3674 */
3675 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3676 if (!test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3677 rc = -ERESTARTSYS;
3678 goto out_err;
3679 }
3680 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
3681 }
3682 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3683
3684 dasd_set_target_state(device, DASD_STATE_NEW);
3685 /* dasd_delete_device destroys the device reference. */
3686 block = device->block;
3687 dasd_delete_device(device);
3688 /*
3689 * life cycle of block is bound to device, so delete it after
3690 * device was safely removed
3691 */
3692 if (block)
3693 dasd_free_block(block);
3694
3695 return 0;
3696
3697 interrupted:
3698 /* interrupted by signal */
3699 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3700 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
3701 clear_bit(DASD_FLAG_OFFLINE, &device->flags);
3702 out_err:
3703 dasd_put_device(device);
3704 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3705 return rc;
3706 }
3707 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
3708
3709 int dasd_generic_last_path_gone(struct dasd_device *device)
3710 {
3711 struct dasd_ccw_req *cqr;
3712
3713 dev_warn(&device->cdev->dev, "No operational channel path is left "
3714 "for the device\n");
3715 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone");
3716 /* First of all call extended error reporting. */
3717 dasd_eer_write(device, NULL, DASD_EER_NOPATH);
3718
3719 if (device->state < DASD_STATE_BASIC)
3720 return 0;
3721 /* Device is active. We want to keep it. */
3722 list_for_each_entry(cqr, &device->ccw_queue, devlist)
3723 if ((cqr->status == DASD_CQR_IN_IO) ||
3724 (cqr->status == DASD_CQR_CLEAR_PENDING)) {
3725 cqr->status = DASD_CQR_QUEUED;
3726 cqr->retries++;
3727 }
3728 dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT);
3729 dasd_device_clear_timer(device);
3730 dasd_schedule_device_bh(device);
3731 return 1;
3732 }
3733 EXPORT_SYMBOL_GPL(dasd_generic_last_path_gone);
3734
3735 int dasd_generic_path_operational(struct dasd_device *device)
3736 {
3737 dev_info(&device->cdev->dev, "A channel path to the device has become "
3738 "operational\n");
3739 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational");
3740 dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT);
3741 if (device->stopped & DASD_UNRESUMED_PM) {
3742 dasd_device_remove_stop_bits(device, DASD_UNRESUMED_PM);
3743 dasd_restore_device(device);
3744 return 1;
3745 }
3746 dasd_schedule_device_bh(device);
3747 if (device->block) {
3748 dasd_schedule_block_bh(device->block);
3749 if (device->block->request_queue)
3750 blk_mq_run_hw_queues(device->block->request_queue,
3751 true);
3752 }
3753
3754 if (!device->stopped)
3755 wake_up(&generic_waitq);
3756
3757 return 1;
3758 }
3759 EXPORT_SYMBOL_GPL(dasd_generic_path_operational);
3760
3761 int dasd_generic_notify(struct ccw_device *cdev, int event)
3762 {
3763 struct dasd_device *device;
3764 int ret;
3765
3766 device = dasd_device_from_cdev_locked(cdev);
3767 if (IS_ERR(device))
3768 return 0;
3769 ret = 0;
3770 switch (event) {
3771 case CIO_GONE:
3772 case CIO_BOXED:
3773 case CIO_NO_PATH:
3774 dasd_path_no_path(device);
3775 ret = dasd_generic_last_path_gone(device);
3776 break;
3777 case CIO_OPER:
3778 ret = 1;
3779 if (dasd_path_get_opm(device))
3780 ret = dasd_generic_path_operational(device);
3781 break;
3782 }
3783 dasd_put_device(device);
3784 return ret;
3785 }
3786 EXPORT_SYMBOL_GPL(dasd_generic_notify);
3787
3788 void dasd_generic_path_event(struct ccw_device *cdev, int *path_event)
3789 {
3790 struct dasd_device *device;
3791 int chp, oldopm, hpfpm, ifccpm;
3792
3793 device = dasd_device_from_cdev_locked(cdev);
3794 if (IS_ERR(device))
3795 return;
3796
3797 oldopm = dasd_path_get_opm(device);
3798 for (chp = 0; chp < 8; chp++) {
3799 if (path_event[chp] & PE_PATH_GONE) {
3800 dasd_path_notoper(device, chp);
3801 }
3802 if (path_event[chp] & PE_PATH_AVAILABLE) {
3803 dasd_path_available(device, chp);
3804 dasd_schedule_device_bh(device);
3805 }
3806 if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) {
3807 if (!dasd_path_is_operational(device, chp) &&
3808 !dasd_path_need_verify(device, chp)) {
3809 /*
3810 * we can not establish a pathgroup on an
3811 * unavailable path, so trigger a path
3812 * verification first
3813 */
3814 dasd_path_available(device, chp);
3815 dasd_schedule_device_bh(device);
3816 }
3817 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
3818 "Pathgroup re-established\n");
3819 if (device->discipline->kick_validate)
3820 device->discipline->kick_validate(device);
3821 }
3822 }
3823 hpfpm = dasd_path_get_hpfpm(device);
3824 ifccpm = dasd_path_get_ifccpm(device);
3825 if (!dasd_path_get_opm(device) && hpfpm) {
3826 /*
3827 * device has no operational paths but at least one path is
3828 * disabled due to HPF errors
3829 * disable HPF at all and use the path(s) again
3830 */
3831 if (device->discipline->disable_hpf)
3832 device->discipline->disable_hpf(device);
3833 dasd_device_set_stop_bits(device, DASD_STOPPED_NOT_ACC);
3834 dasd_path_set_tbvpm(device, hpfpm);
3835 dasd_schedule_device_bh(device);
3836 dasd_schedule_requeue(device);
3837 } else if (!dasd_path_get_opm(device) && ifccpm) {
3838 /*
3839 * device has no operational paths but at least one path is
3840 * disabled due to IFCC errors
3841 * trigger path verification on paths with IFCC errors
3842 */
3843 dasd_path_set_tbvpm(device, ifccpm);
3844 dasd_schedule_device_bh(device);
3845 }
3846 if (oldopm && !dasd_path_get_opm(device) && !hpfpm && !ifccpm) {
3847 dev_warn(&device->cdev->dev,
3848 "No verified channel paths remain for the device\n");
3849 DBF_DEV_EVENT(DBF_WARNING, device,
3850 "%s", "last verified path gone");
3851 dasd_eer_write(device, NULL, DASD_EER_NOPATH);
3852 dasd_device_set_stop_bits(device,
3853 DASD_STOPPED_DC_WAIT);
3854 }
3855 dasd_put_device(device);
3856 }
3857 EXPORT_SYMBOL_GPL(dasd_generic_path_event);
3858
3859 int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm)
3860 {
3861 if (!dasd_path_get_opm(device) && lpm) {
3862 dasd_path_set_opm(device, lpm);
3863 dasd_generic_path_operational(device);
3864 } else
3865 dasd_path_add_opm(device, lpm);
3866 return 0;
3867 }
3868 EXPORT_SYMBOL_GPL(dasd_generic_verify_path);
3869
3870 /*
3871 * clear active requests and requeue them to block layer if possible
3872 */
3873 static int dasd_generic_requeue_all_requests(struct dasd_device *device)
3874 {
3875 struct list_head requeue_queue;
3876 struct dasd_ccw_req *cqr, *n;
3877 struct dasd_ccw_req *refers;
3878 int rc;
3879
3880 INIT_LIST_HEAD(&requeue_queue);
3881 spin_lock_irq(get_ccwdev_lock(device->cdev));
3882 rc = 0;
3883 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
3884 /* Check status and move request to flush_queue */
3885 if (cqr->status == DASD_CQR_IN_IO) {
3886 rc = device->discipline->term_IO(cqr);
3887 if (rc) {
3888 /* unable to terminate requeust */
3889 dev_err(&device->cdev->dev,
3890 "Unable to terminate request %p "
3891 "on suspend\n", cqr);
3892 spin_unlock_irq(get_ccwdev_lock(device->cdev));
3893 dasd_put_device(device);
3894 return rc;
3895 }
3896 }
3897 list_move_tail(&cqr->devlist, &requeue_queue);
3898 }
3899 spin_unlock_irq(get_ccwdev_lock(device->cdev));
3900
3901 list_for_each_entry_safe(cqr, n, &requeue_queue, devlist) {
3902 wait_event(dasd_flush_wq,
3903 (cqr->status != DASD_CQR_CLEAR_PENDING));
3904
3905 /* mark sleepon requests as ended */
3906 if (cqr->callback_data == DASD_SLEEPON_START_TAG)
3907 cqr->callback_data = DASD_SLEEPON_END_TAG;
3908
3909 /* remove requests from device and block queue */
3910 list_del_init(&cqr->devlist);
3911 while (cqr->refers != NULL) {
3912 refers = cqr->refers;
3913 /* remove the request from the block queue */
3914 list_del(&cqr->blocklist);
3915 /* free the finished erp request */
3916 dasd_free_erp_request(cqr, cqr->memdev);
3917 cqr = refers;
3918 }
3919
3920 /*
3921 * requeue requests to blocklayer will only work
3922 * for block device requests
3923 */
3924 if (_dasd_requeue_request(cqr))
3925 continue;
3926
3927 if (cqr->block)
3928 list_del_init(&cqr->blocklist);
3929 cqr->block->base->discipline->free_cp(
3930 cqr, (struct request *) cqr->callback_data);
3931 }
3932
3933 /*
3934 * if requests remain then they are internal request
3935 * and go back to the device queue
3936 */
3937 if (!list_empty(&requeue_queue)) {
3938 /* move freeze_queue to start of the ccw_queue */
3939 spin_lock_irq(get_ccwdev_lock(device->cdev));
3940 list_splice_tail(&requeue_queue, &device->ccw_queue);
3941 spin_unlock_irq(get_ccwdev_lock(device->cdev));
3942 }
3943 /* wake up generic waitqueue for eventually ended sleepon requests */
3944 wake_up(&generic_waitq);
3945 return rc;
3946 }
3947
3948 static void do_requeue_requests(struct work_struct *work)
3949 {
3950 struct dasd_device *device = container_of(work, struct dasd_device,
3951 requeue_requests);
3952 dasd_generic_requeue_all_requests(device);
3953 dasd_device_remove_stop_bits(device, DASD_STOPPED_NOT_ACC);
3954 if (device->block)
3955 dasd_schedule_block_bh(device->block);
3956 dasd_put_device(device);
3957 }
3958
3959 void dasd_schedule_requeue(struct dasd_device *device)
3960 {
3961 dasd_get_device(device);
3962 /* queue call to dasd_reload_device to the kernel event daemon. */
3963 if (!schedule_work(&device->requeue_requests))
3964 dasd_put_device(device);
3965 }
3966 EXPORT_SYMBOL(dasd_schedule_requeue);
3967
3968 int dasd_generic_pm_freeze(struct ccw_device *cdev)
3969 {
3970 struct dasd_device *device = dasd_device_from_cdev(cdev);
3971
3972 if (IS_ERR(device))
3973 return PTR_ERR(device);
3974
3975 /* mark device as suspended */
3976 set_bit(DASD_FLAG_SUSPENDED, &device->flags);
3977
3978 if (device->discipline->freeze)
3979 device->discipline->freeze(device);
3980
3981 /* disallow new I/O */
3982 dasd_device_set_stop_bits(device, DASD_STOPPED_PM);
3983
3984 return dasd_generic_requeue_all_requests(device);
3985 }
3986 EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze);
3987
3988 int dasd_generic_restore_device(struct ccw_device *cdev)
3989 {
3990 struct dasd_device *device = dasd_device_from_cdev(cdev);
3991 int rc = 0;
3992
3993 if (IS_ERR(device))
3994 return PTR_ERR(device);
3995
3996 /* allow new IO again */
3997 dasd_device_remove_stop_bits(device,
3998 (DASD_STOPPED_PM | DASD_UNRESUMED_PM));
3999
4000 dasd_schedule_device_bh(device);
4001
4002 /*
4003 * call discipline restore function
4004 * if device is stopped do nothing e.g. for disconnected devices
4005 */
4006 if (device->discipline->restore && !(device->stopped))
4007 rc = device->discipline->restore(device);
4008 if (rc || device->stopped)
4009 /*
4010 * if the resume failed for the DASD we put it in
4011 * an UNRESUMED stop state
4012 */
4013 device->stopped |= DASD_UNRESUMED_PM;
4014
4015 if (device->block) {
4016 dasd_schedule_block_bh(device->block);
4017 if (device->block->request_queue)
4018 blk_mq_run_hw_queues(device->block->request_queue,
4019 true);
4020 }
4021
4022 clear_bit(DASD_FLAG_SUSPENDED, &device->flags);
4023 dasd_put_device(device);
4024 return 0;
4025 }
4026 EXPORT_SYMBOL_GPL(dasd_generic_restore_device);
4027
4028 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
4029 void *rdc_buffer,
4030 int rdc_buffer_size,
4031 int magic)
4032 {
4033 struct dasd_ccw_req *cqr;
4034 struct ccw1 *ccw;
4035 unsigned long *idaw;
4036
4037 cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device);
4038
4039 if (IS_ERR(cqr)) {
4040 /* internal error 13 - Allocating the RDC request failed*/
4041 dev_err(&device->cdev->dev,
4042 "An error occurred in the DASD device driver, "
4043 "reason=%s\n", "13");
4044 return cqr;
4045 }
4046
4047 ccw = cqr->cpaddr;
4048 ccw->cmd_code = CCW_CMD_RDC;
4049 if (idal_is_needed(rdc_buffer, rdc_buffer_size)) {
4050 idaw = (unsigned long *) (cqr->data);
4051 ccw->cda = (__u32)(addr_t) idaw;
4052 ccw->flags = CCW_FLAG_IDA;
4053 idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size);
4054 } else {
4055 ccw->cda = (__u32)(addr_t) rdc_buffer;
4056 ccw->flags = 0;
4057 }
4058
4059 ccw->count = rdc_buffer_size;
4060 cqr->startdev = device;
4061 cqr->memdev = device;
4062 cqr->expires = 10*HZ;
4063 cqr->retries = 256;
4064 cqr->buildclk = get_tod_clock();
4065 cqr->status = DASD_CQR_FILLED;
4066 return cqr;
4067 }
4068
4069
4070 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
4071 void *rdc_buffer, int rdc_buffer_size)
4072 {
4073 int ret;
4074 struct dasd_ccw_req *cqr;
4075
4076 cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size,
4077 magic);
4078 if (IS_ERR(cqr))
4079 return PTR_ERR(cqr);
4080
4081 ret = dasd_sleep_on(cqr);
4082 dasd_sfree_request(cqr, cqr->memdev);
4083 return ret;
4084 }
4085 EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
4086
4087 /*
4088 * In command mode and transport mode we need to look for sense
4089 * data in different places. The sense data itself is allways
4090 * an array of 32 bytes, so we can unify the sense data access
4091 * for both modes.
4092 */
4093 char *dasd_get_sense(struct irb *irb)
4094 {
4095 struct tsb *tsb = NULL;
4096 char *sense = NULL;
4097
4098 if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
4099 if (irb->scsw.tm.tcw)
4100 tsb = tcw_get_tsb((struct tcw *)(unsigned long)
4101 irb->scsw.tm.tcw);
4102 if (tsb && tsb->length == 64 && tsb->flags)
4103 switch (tsb->flags & 0x07) {
4104 case 1: /* tsa_iostat */
4105 sense = tsb->tsa.iostat.sense;
4106 break;
4107 case 2: /* tsa_ddpc */
4108 sense = tsb->tsa.ddpc.sense;
4109 break;
4110 default:
4111 /* currently we don't use interrogate data */
4112 break;
4113 }
4114 } else if (irb->esw.esw0.erw.cons) {
4115 sense = irb->ecw;
4116 }
4117 return sense;
4118 }
4119 EXPORT_SYMBOL_GPL(dasd_get_sense);
4120
4121 void dasd_generic_shutdown(struct ccw_device *cdev)
4122 {
4123 struct dasd_device *device;
4124
4125 device = dasd_device_from_cdev(cdev);
4126 if (IS_ERR(device))
4127 return;
4128
4129 if (device->block)
4130 dasd_schedule_block_bh(device->block);
4131
4132 dasd_schedule_device_bh(device);
4133
4134 wait_event(shutdown_waitq, _wait_for_empty_queues(device));
4135 }
4136 EXPORT_SYMBOL_GPL(dasd_generic_shutdown);
4137
4138 static int __init dasd_init(void)
4139 {
4140 int rc;
4141
4142 init_waitqueue_head(&dasd_init_waitq);
4143 init_waitqueue_head(&dasd_flush_wq);
4144 init_waitqueue_head(&generic_waitq);
4145 init_waitqueue_head(&shutdown_waitq);
4146
4147 /* register 'common' DASD debug area, used for all DBF_XXX calls */
4148 dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
4149 if (dasd_debug_area == NULL) {
4150 rc = -ENOMEM;
4151 goto failed;
4152 }
4153 debug_register_view(dasd_debug_area, &debug_sprintf_view);
4154 debug_set_level(dasd_debug_area, DBF_WARNING);
4155
4156 DBF_EVENT(DBF_EMERG, "%s", "debug area created");
4157
4158 dasd_diag_discipline_pointer = NULL;
4159
4160 dasd_statistics_createroot();
4161
4162 rc = dasd_devmap_init();
4163 if (rc)
4164 goto failed;
4165 rc = dasd_gendisk_init();
4166 if (rc)
4167 goto failed;
4168 rc = dasd_parse();
4169 if (rc)
4170 goto failed;
4171 rc = dasd_eer_init();
4172 if (rc)
4173 goto failed;
4174 #ifdef CONFIG_PROC_FS
4175 rc = dasd_proc_init();
4176 if (rc)
4177 goto failed;
4178 #endif
4179
4180 return 0;
4181 failed:
4182 pr_info("The DASD device driver could not be initialized\n");
4183 dasd_exit();
4184 return rc;
4185 }
4186
4187 module_init(dasd_init);
4188 module_exit(dasd_exit);
CRIS linux kernel tree