1 /*
2 * File...........: linux/drivers/s390/block/dasd.c
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_SLEEPON_START_TAG (void *) 1
43 #define DASD_SLEEPON_END_TAG (void *) 2
44
45 /*
46 * SECTION: exported variables of dasd.c
47 */
48 debug_info_t *dasd_debug_area;
49 static struct dentry *dasd_debugfs_root_entry;
50 struct dasd_discipline *dasd_diag_discipline_pointer;
51 void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
52
53 MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>");
54 MODULE_DESCRIPTION("Linux on S/390 DASD device driver,"
55 " Copyright 2000 IBM Corporation");
56 MODULE_SUPPORTED_DEVICE("dasd");
57 MODULE_LICENSE("GPL");
58
59 /*
60 * SECTION: prototypes for static functions of dasd.c
61 */
62 static int dasd_alloc_queue(struct dasd_block *);
63 static void dasd_setup_queue(struct dasd_block *);
64 static void dasd_free_queue(struct dasd_block *);
65 static void dasd_flush_request_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 dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
73 static void dasd_device_timeout(unsigned long);
74 static void dasd_block_timeout(unsigned long);
75 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
76 static void dasd_profile_init(struct dasd_profile *, struct dentry *);
77 static void dasd_profile_exit(struct dasd_profile *);
78
79 /*
80 * SECTION: Operations on the device structure.
81 */
82 static wait_queue_head_t dasd_init_waitq;
83 static wait_queue_head_t dasd_flush_wq;
84 static wait_queue_head_t generic_waitq;
85
86 /*
87 * Allocate memory for a new device structure.
88 */
dasd_alloc_device(void)89 struct dasd_device *dasd_alloc_device(void)
90 {
91 struct dasd_device *device;
92
93 device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
94 if (!device)
95 return ERR_PTR(-ENOMEM);
96
97 /* Get two pages for normal block device operations. */
98 device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
99 if (!device->ccw_mem) {
100 kfree(device);
101 return ERR_PTR(-ENOMEM);
102 }
103 /* Get one page for error recovery. */
104 device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
105 if (!device->erp_mem) {
106 free_pages((unsigned long) device->ccw_mem, 1);
107 kfree(device);
108 return ERR_PTR(-ENOMEM);
109 }
110
111 dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
112 dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
113 spin_lock_init(&device->mem_lock);
114 atomic_set(&device->tasklet_scheduled, 0);
115 tasklet_init(&device->tasklet,
116 (void (*)(unsigned long)) dasd_device_tasklet,
117 (unsigned long) device);
118 INIT_LIST_HEAD(&device->ccw_queue);
119 init_timer(&device->timer);
120 device->timer.function = dasd_device_timeout;
121 device->timer.data = (unsigned long) device;
122 INIT_WORK(&device->kick_work, do_kick_device);
123 INIT_WORK(&device->restore_device, do_restore_device);
124 INIT_WORK(&device->reload_device, do_reload_device);
125 device->state = DASD_STATE_NEW;
126 device->target = DASD_STATE_NEW;
127 mutex_init(&device->state_mutex);
128 spin_lock_init(&device->profile.lock);
129 return device;
130 }
131
132 /*
133 * Free memory of a device structure.
134 */
dasd_free_device(struct dasd_device * device)135 void dasd_free_device(struct dasd_device *device)
136 {
137 kfree(device->private);
138 free_page((unsigned long) device->erp_mem);
139 free_pages((unsigned long) device->ccw_mem, 1);
140 kfree(device);
141 }
142
143 /*
144 * Allocate memory for a new device structure.
145 */
dasd_alloc_block(void)146 struct dasd_block *dasd_alloc_block(void)
147 {
148 struct dasd_block *block;
149
150 block = kzalloc(sizeof(*block), GFP_ATOMIC);
151 if (!block)
152 return ERR_PTR(-ENOMEM);
153 /* open_count = 0 means device online but not in use */
154 atomic_set(&block->open_count, -1);
155
156 spin_lock_init(&block->request_queue_lock);
157 atomic_set(&block->tasklet_scheduled, 0);
158 tasklet_init(&block->tasklet,
159 (void (*)(unsigned long)) dasd_block_tasklet,
160 (unsigned long) block);
161 INIT_LIST_HEAD(&block->ccw_queue);
162 spin_lock_init(&block->queue_lock);
163 init_timer(&block->timer);
164 block->timer.function = dasd_block_timeout;
165 block->timer.data = (unsigned long) block;
166 spin_lock_init(&block->profile.lock);
167
168 return block;
169 }
170
171 /*
172 * Free memory of a device structure.
173 */
dasd_free_block(struct dasd_block * block)174 void dasd_free_block(struct dasd_block *block)
175 {
176 kfree(block);
177 }
178
179 /*
180 * Make a new device known to the system.
181 */
dasd_state_new_to_known(struct dasd_device * device)182 static int dasd_state_new_to_known(struct dasd_device *device)
183 {
184 int rc;
185
186 /*
187 * As long as the device is not in state DASD_STATE_NEW we want to
188 * keep the reference count > 0.
189 */
190 dasd_get_device(device);
191
192 if (device->block) {
193 rc = dasd_alloc_queue(device->block);
194 if (rc) {
195 dasd_put_device(device);
196 return rc;
197 }
198 }
199 device->state = DASD_STATE_KNOWN;
200 return 0;
201 }
202
203 /*
204 * Let the system forget about a device.
205 */
dasd_state_known_to_new(struct dasd_device * device)206 static int dasd_state_known_to_new(struct dasd_device *device)
207 {
208 /* Disable extended error reporting for this device. */
209 dasd_eer_disable(device);
210 /* Forget the discipline information. */
211 if (device->discipline) {
212 if (device->discipline->uncheck_device)
213 device->discipline->uncheck_device(device);
214 module_put(device->discipline->owner);
215 }
216 device->discipline = NULL;
217 if (device->base_discipline)
218 module_put(device->base_discipline->owner);
219 device->base_discipline = NULL;
220 device->state = DASD_STATE_NEW;
221
222 if (device->block)
223 dasd_free_queue(device->block);
224
225 /* Give up reference we took in dasd_state_new_to_known. */
226 dasd_put_device(device);
227 return 0;
228 }
229
dasd_debugfs_setup(const char * name,struct dentry * base_dentry)230 static struct dentry *dasd_debugfs_setup(const char *name,
231 struct dentry *base_dentry)
232 {
233 struct dentry *pde;
234
235 if (!base_dentry)
236 return NULL;
237 pde = debugfs_create_dir(name, base_dentry);
238 if (!pde || IS_ERR(pde))
239 return NULL;
240 return pde;
241 }
242
243 /*
244 * Request the irq line for the device.
245 */
dasd_state_known_to_basic(struct dasd_device * device)246 static int dasd_state_known_to_basic(struct dasd_device *device)
247 {
248 struct dasd_block *block = device->block;
249 int rc;
250
251 /* Allocate and register gendisk structure. */
252 if (block) {
253 rc = dasd_gendisk_alloc(block);
254 if (rc)
255 return rc;
256 block->debugfs_dentry =
257 dasd_debugfs_setup(block->gdp->disk_name,
258 dasd_debugfs_root_entry);
259 dasd_profile_init(&block->profile, block->debugfs_dentry);
260 if (dasd_global_profile_level == DASD_PROFILE_ON)
261 dasd_profile_on(&device->block->profile);
262 }
263 device->debugfs_dentry =
264 dasd_debugfs_setup(dev_name(&device->cdev->dev),
265 dasd_debugfs_root_entry);
266 dasd_profile_init(&device->profile, device->debugfs_dentry);
267
268 /* register 'device' debug area, used for all DBF_DEV_XXX calls */
269 device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
270 8 * sizeof(long));
271 debug_register_view(device->debug_area, &debug_sprintf_view);
272 debug_set_level(device->debug_area, DBF_WARNING);
273 DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
274
275 device->state = DASD_STATE_BASIC;
276 return 0;
277 }
278
279 /*
280 * Release the irq line for the device. Terminate any running i/o.
281 */
dasd_state_basic_to_known(struct dasd_device * device)282 static int dasd_state_basic_to_known(struct dasd_device *device)
283 {
284 int rc;
285 if (device->block) {
286 dasd_profile_exit(&device->block->profile);
287 if (device->block->debugfs_dentry)
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 if (device->debugfs_dentry)
298 debugfs_remove(device->debugfs_dentry);
299
300 DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
301 if (device->debug_area != NULL) {
302 debug_unregister(device->debug_area);
303 device->debug_area = NULL;
304 }
305 device->state = DASD_STATE_KNOWN;
306 return 0;
307 }
308
309 /*
310 * Do the initial analysis. The do_analysis function may return
311 * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
312 * until the discipline decides to continue the startup sequence
313 * by calling the function dasd_change_state. The eckd disciplines
314 * uses this to start a ccw that detects the format. The completion
315 * interrupt for this detection ccw uses the kernel event daemon to
316 * trigger the call to dasd_change_state. All this is done in the
317 * discipline code, see dasd_eckd.c.
318 * After the analysis ccw is done (do_analysis returned 0) the block
319 * device is setup.
320 * In case the analysis returns an error, the device setup is stopped
321 * (a fake disk was already added to allow formatting).
322 */
dasd_state_basic_to_ready(struct dasd_device * device)323 static int dasd_state_basic_to_ready(struct dasd_device *device)
324 {
325 int rc;
326 struct dasd_block *block;
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 return rc;
338 }
339 dasd_setup_queue(block);
340 set_capacity(block->gdp,
341 block->blocks << block->s2b_shift);
342 device->state = DASD_STATE_READY;
343 rc = dasd_scan_partitions(block);
344 if (rc)
345 device->state = DASD_STATE_BASIC;
346 } else {
347 device->state = DASD_STATE_READY;
348 }
349 return rc;
350 }
351
352 /*
353 * Remove device from block device layer. Destroy dirty buffers.
354 * Forget format information. Check if the target level is basic
355 * and if it is create fake disk for formatting.
356 */
dasd_state_ready_to_basic(struct dasd_device * device)357 static int dasd_state_ready_to_basic(struct dasd_device *device)
358 {
359 int rc;
360
361 device->state = DASD_STATE_BASIC;
362 if (device->block) {
363 struct dasd_block *block = device->block;
364 rc = dasd_flush_block_queue(block);
365 if (rc) {
366 device->state = DASD_STATE_READY;
367 return rc;
368 }
369 dasd_flush_request_queue(block);
370 dasd_destroy_partitions(block);
371 block->blocks = 0;
372 block->bp_block = 0;
373 block->s2b_shift = 0;
374 }
375 return 0;
376 }
377
378 /*
379 * Back to basic.
380 */
dasd_state_unfmt_to_basic(struct dasd_device * device)381 static int dasd_state_unfmt_to_basic(struct dasd_device *device)
382 {
383 device->state = DASD_STATE_BASIC;
384 return 0;
385 }
386
387 /*
388 * Make the device online and schedule the bottom half to start
389 * the requeueing of requests from the linux request queue to the
390 * ccw queue.
391 */
392 static int
dasd_state_ready_to_online(struct dasd_device * device)393 dasd_state_ready_to_online(struct dasd_device * device)
394 {
395 int rc;
396 struct gendisk *disk;
397 struct disk_part_iter piter;
398 struct hd_struct *part;
399
400 if (device->discipline->ready_to_online) {
401 rc = device->discipline->ready_to_online(device);
402 if (rc)
403 return rc;
404 }
405 device->state = DASD_STATE_ONLINE;
406 if (device->block) {
407 dasd_schedule_block_bh(device->block);
408 if ((device->features & DASD_FEATURE_USERAW)) {
409 disk = device->block->gdp;
410 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
411 return 0;
412 }
413 disk = device->block->bdev->bd_disk;
414 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
415 while ((part = disk_part_iter_next(&piter)))
416 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
417 disk_part_iter_exit(&piter);
418 }
419 return 0;
420 }
421
422 /*
423 * Stop the requeueing of requests again.
424 */
dasd_state_online_to_ready(struct dasd_device * device)425 static int dasd_state_online_to_ready(struct dasd_device *device)
426 {
427 int rc;
428 struct gendisk *disk;
429 struct disk_part_iter piter;
430 struct hd_struct *part;
431
432 if (device->discipline->online_to_ready) {
433 rc = device->discipline->online_to_ready(device);
434 if (rc)
435 return rc;
436 }
437 device->state = DASD_STATE_READY;
438 if (device->block && !(device->features & DASD_FEATURE_USERAW)) {
439 disk = device->block->bdev->bd_disk;
440 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
441 while ((part = disk_part_iter_next(&piter)))
442 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
443 disk_part_iter_exit(&piter);
444 }
445 return 0;
446 }
447
448 /*
449 * Device startup state changes.
450 */
dasd_increase_state(struct dasd_device * device)451 static int dasd_increase_state(struct dasd_device *device)
452 {
453 int rc;
454
455 rc = 0;
456 if (device->state == DASD_STATE_NEW &&
457 device->target >= DASD_STATE_KNOWN)
458 rc = dasd_state_new_to_known(device);
459
460 if (!rc &&
461 device->state == DASD_STATE_KNOWN &&
462 device->target >= DASD_STATE_BASIC)
463 rc = dasd_state_known_to_basic(device);
464
465 if (!rc &&
466 device->state == DASD_STATE_BASIC &&
467 device->target >= DASD_STATE_READY)
468 rc = dasd_state_basic_to_ready(device);
469
470 if (!rc &&
471 device->state == DASD_STATE_UNFMT &&
472 device->target > DASD_STATE_UNFMT)
473 rc = -EPERM;
474
475 if (!rc &&
476 device->state == DASD_STATE_READY &&
477 device->target >= DASD_STATE_ONLINE)
478 rc = dasd_state_ready_to_online(device);
479
480 return rc;
481 }
482
483 /*
484 * Device shutdown state changes.
485 */
dasd_decrease_state(struct dasd_device * device)486 static int dasd_decrease_state(struct dasd_device *device)
487 {
488 int rc;
489
490 rc = 0;
491 if (device->state == DASD_STATE_ONLINE &&
492 device->target <= DASD_STATE_READY)
493 rc = dasd_state_online_to_ready(device);
494
495 if (!rc &&
496 device->state == DASD_STATE_READY &&
497 device->target <= DASD_STATE_BASIC)
498 rc = dasd_state_ready_to_basic(device);
499
500 if (!rc &&
501 device->state == DASD_STATE_UNFMT &&
502 device->target <= DASD_STATE_BASIC)
503 rc = dasd_state_unfmt_to_basic(device);
504
505 if (!rc &&
506 device->state == DASD_STATE_BASIC &&
507 device->target <= DASD_STATE_KNOWN)
508 rc = dasd_state_basic_to_known(device);
509
510 if (!rc &&
511 device->state == DASD_STATE_KNOWN &&
512 device->target <= DASD_STATE_NEW)
513 rc = dasd_state_known_to_new(device);
514
515 return rc;
516 }
517
518 /*
519 * This is the main startup/shutdown routine.
520 */
dasd_change_state(struct dasd_device * device)521 static void dasd_change_state(struct dasd_device *device)
522 {
523 int rc;
524
525 if (device->state == device->target)
526 /* Already where we want to go today... */
527 return;
528 if (device->state < device->target)
529 rc = dasd_increase_state(device);
530 else
531 rc = dasd_decrease_state(device);
532 if (rc == -EAGAIN)
533 return;
534 if (rc)
535 device->target = device->state;
536
537 if (device->state == device->target)
538 wake_up(&dasd_init_waitq);
539
540 /* let user-space know that the device status changed */
541 kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
542 }
543
544 /*
545 * Kick starter for devices that did not complete the startup/shutdown
546 * procedure or were sleeping because of a pending state.
547 * dasd_kick_device will schedule a call do do_kick_device to the kernel
548 * event daemon.
549 */
do_kick_device(struct work_struct * work)550 static void do_kick_device(struct work_struct *work)
551 {
552 struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
553 mutex_lock(&device->state_mutex);
554 dasd_change_state(device);
555 mutex_unlock(&device->state_mutex);
556 dasd_schedule_device_bh(device);
557 dasd_put_device(device);
558 }
559
dasd_kick_device(struct dasd_device * device)560 void dasd_kick_device(struct dasd_device *device)
561 {
562 dasd_get_device(device);
563 /* queue call to dasd_kick_device to the kernel event daemon. */
564 schedule_work(&device->kick_work);
565 }
566
567 /*
568 * dasd_reload_device will schedule a call do do_reload_device to the kernel
569 * event daemon.
570 */
do_reload_device(struct work_struct * work)571 static void do_reload_device(struct work_struct *work)
572 {
573 struct dasd_device *device = container_of(work, struct dasd_device,
574 reload_device);
575 device->discipline->reload(device);
576 dasd_put_device(device);
577 }
578
dasd_reload_device(struct dasd_device * device)579 void dasd_reload_device(struct dasd_device *device)
580 {
581 dasd_get_device(device);
582 /* queue call to dasd_reload_device to the kernel event daemon. */
583 schedule_work(&device->reload_device);
584 }
585 EXPORT_SYMBOL(dasd_reload_device);
586
587 /*
588 * dasd_restore_device will schedule a call do do_restore_device to the kernel
589 * event daemon.
590 */
do_restore_device(struct work_struct * work)591 static void do_restore_device(struct work_struct *work)
592 {
593 struct dasd_device *device = container_of(work, struct dasd_device,
594 restore_device);
595 device->cdev->drv->restore(device->cdev);
596 dasd_put_device(device);
597 }
598
dasd_restore_device(struct dasd_device * device)599 void dasd_restore_device(struct dasd_device *device)
600 {
601 dasd_get_device(device);
602 /* queue call to dasd_restore_device to the kernel event daemon. */
603 schedule_work(&device->restore_device);
604 }
605
606 /*
607 * Set the target state for a device and starts the state change.
608 */
dasd_set_target_state(struct dasd_device * device,int target)609 void dasd_set_target_state(struct dasd_device *device, int target)
610 {
611 dasd_get_device(device);
612 mutex_lock(&device->state_mutex);
613 /* If we are in probeonly mode stop at DASD_STATE_READY. */
614 if (dasd_probeonly && target > DASD_STATE_READY)
615 target = DASD_STATE_READY;
616 if (device->target != target) {
617 if (device->state == target)
618 wake_up(&dasd_init_waitq);
619 device->target = target;
620 }
621 if (device->state != device->target)
622 dasd_change_state(device);
623 mutex_unlock(&device->state_mutex);
624 dasd_put_device(device);
625 }
626
627 /*
628 * Enable devices with device numbers in [from..to].
629 */
_wait_for_device(struct dasd_device * device)630 static inline int _wait_for_device(struct dasd_device *device)
631 {
632 return (device->state == device->target);
633 }
634
dasd_enable_device(struct dasd_device * device)635 void dasd_enable_device(struct dasd_device *device)
636 {
637 dasd_set_target_state(device, DASD_STATE_ONLINE);
638 if (device->state <= DASD_STATE_KNOWN)
639 /* No discipline for device found. */
640 dasd_set_target_state(device, DASD_STATE_NEW);
641 /* Now wait for the devices to come up. */
642 wait_event(dasd_init_waitq, _wait_for_device(device));
643
644 dasd_reload_device(device);
645 if (device->discipline->kick_validate)
646 device->discipline->kick_validate(device);
647 }
648
649 /*
650 * SECTION: device operation (interrupt handler, start i/o, term i/o ...)
651 */
652
653 unsigned int dasd_global_profile_level = DASD_PROFILE_OFF;
654
655 #ifdef CONFIG_DASD_PROFILE
656 struct dasd_profile_info dasd_global_profile_data;
657 static struct dentry *dasd_global_profile_dentry;
658 static struct dentry *dasd_debugfs_global_entry;
659
660 /*
661 * Add profiling information for cqr before execution.
662 */
dasd_profile_start(struct dasd_block * block,struct dasd_ccw_req * cqr,struct request * req)663 static void dasd_profile_start(struct dasd_block *block,
664 struct dasd_ccw_req *cqr,
665 struct request *req)
666 {
667 struct list_head *l;
668 unsigned int counter;
669 struct dasd_device *device;
670
671 /* count the length of the chanq for statistics */
672 counter = 0;
673 if (dasd_global_profile_level || block->profile.data)
674 list_for_each(l, &block->ccw_queue)
675 if (++counter >= 31)
676 break;
677
678 if (dasd_global_profile_level) {
679 dasd_global_profile_data.dasd_io_nr_req[counter]++;
680 if (rq_data_dir(req) == READ)
681 dasd_global_profile_data.dasd_read_nr_req[counter]++;
682 }
683
684 spin_lock(&block->profile.lock);
685 if (block->profile.data)
686 block->profile.data->dasd_io_nr_req[counter]++;
687 if (rq_data_dir(req) == READ)
688 block->profile.data->dasd_read_nr_req[counter]++;
689 spin_unlock(&block->profile.lock);
690
691 /*
692 * We count the request for the start device, even though it may run on
693 * some other device due to error recovery. This way we make sure that
694 * we count each request only once.
695 */
696 device = cqr->startdev;
697 if (device->profile.data) {
698 counter = 1; /* request is not yet queued on the start device */
699 list_for_each(l, &device->ccw_queue)
700 if (++counter >= 31)
701 break;
702 }
703 spin_lock(&device->profile.lock);
704 if (device->profile.data) {
705 device->profile.data->dasd_io_nr_req[counter]++;
706 if (rq_data_dir(req) == READ)
707 device->profile.data->dasd_read_nr_req[counter]++;
708 }
709 spin_unlock(&device->profile.lock);
710 }
711
712 /*
713 * Add profiling information for cqr after execution.
714 */
715
716 #define dasd_profile_counter(value, index) \
717 { \
718 for (index = 0; index < 31 && value >> (2+index); index++) \
719 ; \
720 }
721
dasd_profile_end_add_data(struct dasd_profile_info * data,int is_alias,int is_tpm,int is_read,long sectors,int sectors_ind,int tottime_ind,int tottimeps_ind,int strtime_ind,int irqtime_ind,int irqtimeps_ind,int endtime_ind)722 static void dasd_profile_end_add_data(struct dasd_profile_info *data,
723 int is_alias,
724 int is_tpm,
725 int is_read,
726 long sectors,
727 int sectors_ind,
728 int tottime_ind,
729 int tottimeps_ind,
730 int strtime_ind,
731 int irqtime_ind,
732 int irqtimeps_ind,
733 int endtime_ind)
734 {
735 /* in case of an overflow, reset the whole profile */
736 if (data->dasd_io_reqs == UINT_MAX) {
737 memset(data, 0, sizeof(*data));
738 getnstimeofday(&data->starttod);
739 }
740 data->dasd_io_reqs++;
741 data->dasd_io_sects += sectors;
742 if (is_alias)
743 data->dasd_io_alias++;
744 if (is_tpm)
745 data->dasd_io_tpm++;
746
747 data->dasd_io_secs[sectors_ind]++;
748 data->dasd_io_times[tottime_ind]++;
749 data->dasd_io_timps[tottimeps_ind]++;
750 data->dasd_io_time1[strtime_ind]++;
751 data->dasd_io_time2[irqtime_ind]++;
752 data->dasd_io_time2ps[irqtimeps_ind]++;
753 data->dasd_io_time3[endtime_ind]++;
754
755 if (is_read) {
756 data->dasd_read_reqs++;
757 data->dasd_read_sects += sectors;
758 if (is_alias)
759 data->dasd_read_alias++;
760 if (is_tpm)
761 data->dasd_read_tpm++;
762 data->dasd_read_secs[sectors_ind]++;
763 data->dasd_read_times[tottime_ind]++;
764 data->dasd_read_time1[strtime_ind]++;
765 data->dasd_read_time2[irqtime_ind]++;
766 data->dasd_read_time3[endtime_ind]++;
767 }
768 }
769
dasd_profile_end(struct dasd_block * block,struct dasd_ccw_req * cqr,struct request * req)770 static void dasd_profile_end(struct dasd_block *block,
771 struct dasd_ccw_req *cqr,
772 struct request *req)
773 {
774 long strtime, irqtime, endtime, tottime; /* in microseconds */
775 long tottimeps, sectors;
776 struct dasd_device *device;
777 int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind;
778 int irqtime_ind, irqtimeps_ind, endtime_ind;
779
780 device = cqr->startdev;
781 if (!(dasd_global_profile_level ||
782 block->profile.data ||
783 device->profile.data))
784 return;
785
786 sectors = blk_rq_sectors(req);
787 if (!cqr->buildclk || !cqr->startclk ||
788 !cqr->stopclk || !cqr->endclk ||
789 !sectors)
790 return;
791
792 strtime = ((cqr->startclk - cqr->buildclk) >> 12);
793 irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
794 endtime = ((cqr->endclk - cqr->stopclk) >> 12);
795 tottime = ((cqr->endclk - cqr->buildclk) >> 12);
796 tottimeps = tottime / sectors;
797
798 dasd_profile_counter(sectors, sectors_ind);
799 dasd_profile_counter(tottime, tottime_ind);
800 dasd_profile_counter(tottimeps, tottimeps_ind);
801 dasd_profile_counter(strtime, strtime_ind);
802 dasd_profile_counter(irqtime, irqtime_ind);
803 dasd_profile_counter(irqtime / sectors, irqtimeps_ind);
804 dasd_profile_counter(endtime, endtime_ind);
805
806 if (dasd_global_profile_level) {
807 dasd_profile_end_add_data(&dasd_global_profile_data,
808 cqr->startdev != block->base,
809 cqr->cpmode == 1,
810 rq_data_dir(req) == READ,
811 sectors, sectors_ind, tottime_ind,
812 tottimeps_ind, strtime_ind,
813 irqtime_ind, irqtimeps_ind,
814 endtime_ind);
815 }
816
817 spin_lock(&block->profile.lock);
818 if (block->profile.data)
819 dasd_profile_end_add_data(block->profile.data,
820 cqr->startdev != block->base,
821 cqr->cpmode == 1,
822 rq_data_dir(req) == READ,
823 sectors, sectors_ind, tottime_ind,
824 tottimeps_ind, strtime_ind,
825 irqtime_ind, irqtimeps_ind,
826 endtime_ind);
827 spin_unlock(&block->profile.lock);
828
829 spin_lock(&device->profile.lock);
830 if (device->profile.data)
831 dasd_profile_end_add_data(device->profile.data,
832 cqr->startdev != block->base,
833 cqr->cpmode == 1,
834 rq_data_dir(req) == READ,
835 sectors, sectors_ind, tottime_ind,
836 tottimeps_ind, strtime_ind,
837 irqtime_ind, irqtimeps_ind,
838 endtime_ind);
839 spin_unlock(&device->profile.lock);
840 }
841
dasd_profile_reset(struct dasd_profile * profile)842 void dasd_profile_reset(struct dasd_profile *profile)
843 {
844 struct dasd_profile_info *data;
845
846 spin_lock_bh(&profile->lock);
847 data = profile->data;
848 if (!data) {
849 spin_unlock_bh(&profile->lock);
850 return;
851 }
852 memset(data, 0, sizeof(*data));
853 getnstimeofday(&data->starttod);
854 spin_unlock_bh(&profile->lock);
855 }
856
dasd_global_profile_reset(void)857 void dasd_global_profile_reset(void)
858 {
859 memset(&dasd_global_profile_data, 0, sizeof(dasd_global_profile_data));
860 getnstimeofday(&dasd_global_profile_data.starttod);
861 }
862
dasd_profile_on(struct dasd_profile * profile)863 int dasd_profile_on(struct dasd_profile *profile)
864 {
865 struct dasd_profile_info *data;
866
867 data = kzalloc(sizeof(*data), GFP_KERNEL);
868 if (!data)
869 return -ENOMEM;
870 spin_lock_bh(&profile->lock);
871 if (profile->data) {
872 spin_unlock_bh(&profile->lock);
873 kfree(data);
874 return 0;
875 }
876 getnstimeofday(&data->starttod);
877 profile->data = data;
878 spin_unlock_bh(&profile->lock);
879 return 0;
880 }
881
dasd_profile_off(struct dasd_profile * profile)882 void dasd_profile_off(struct dasd_profile *profile)
883 {
884 spin_lock_bh(&profile->lock);
885 kfree(profile->data);
886 profile->data = NULL;
887 spin_unlock_bh(&profile->lock);
888 }
889
dasd_get_user_string(const char __user * user_buf,size_t user_len)890 char *dasd_get_user_string(const char __user *user_buf, size_t user_len)
891 {
892 char *buffer;
893
894 buffer = vmalloc(user_len + 1);
895 if (buffer == NULL)
896 return ERR_PTR(-ENOMEM);
897 if (copy_from_user(buffer, user_buf, user_len) != 0) {
898 vfree(buffer);
899 return ERR_PTR(-EFAULT);
900 }
901 /* got the string, now strip linefeed. */
902 if (buffer[user_len - 1] == '\n')
903 buffer[user_len - 1] = 0;
904 else
905 buffer[user_len] = 0;
906 return buffer;
907 }
908
dasd_stats_write(struct file * file,const char __user * user_buf,size_t user_len,loff_t * pos)909 static ssize_t dasd_stats_write(struct file *file,
910 const char __user *user_buf,
911 size_t user_len, loff_t *pos)
912 {
913 char *buffer, *str;
914 int rc;
915 struct seq_file *m = (struct seq_file *)file->private_data;
916 struct dasd_profile *prof = m->private;
917
918 if (user_len > 65536)
919 user_len = 65536;
920 buffer = dasd_get_user_string(user_buf, user_len);
921 if (IS_ERR(buffer))
922 return PTR_ERR(buffer);
923
924 str = skip_spaces(buffer);
925 rc = user_len;
926 if (strncmp(str, "reset", 5) == 0) {
927 dasd_profile_reset(prof);
928 } else if (strncmp(str, "on", 2) == 0) {
929 rc = dasd_profile_on(prof);
930 if (!rc)
931 rc = user_len;
932 } else if (strncmp(str, "off", 3) == 0) {
933 dasd_profile_off(prof);
934 } else
935 rc = -EINVAL;
936 vfree(buffer);
937 return rc;
938 }
939
dasd_stats_array(struct seq_file * m,unsigned int * array)940 static void dasd_stats_array(struct seq_file *m, unsigned int *array)
941 {
942 int i;
943
944 for (i = 0; i < 32; i++)
945 seq_printf(m, "%u ", array[i]);
946 seq_putc(m, '\n');
947 }
948
dasd_stats_seq_print(struct seq_file * m,struct dasd_profile_info * data)949 static void dasd_stats_seq_print(struct seq_file *m,
950 struct dasd_profile_info *data)
951 {
952 seq_printf(m, "start_time %ld.%09ld\n",
953 data->starttod.tv_sec, data->starttod.tv_nsec);
954 seq_printf(m, "total_requests %u\n", data->dasd_io_reqs);
955 seq_printf(m, "total_sectors %u\n", data->dasd_io_sects);
956 seq_printf(m, "total_pav %u\n", data->dasd_io_alias);
957 seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm);
958 seq_printf(m, "histogram_sectors ");
959 dasd_stats_array(m, data->dasd_io_secs);
960 seq_printf(m, "histogram_io_times ");
961 dasd_stats_array(m, data->dasd_io_times);
962 seq_printf(m, "histogram_io_times_weighted ");
963 dasd_stats_array(m, data->dasd_io_timps);
964 seq_printf(m, "histogram_time_build_to_ssch ");
965 dasd_stats_array(m, data->dasd_io_time1);
966 seq_printf(m, "histogram_time_ssch_to_irq ");
967 dasd_stats_array(m, data->dasd_io_time2);
968 seq_printf(m, "histogram_time_ssch_to_irq_weighted ");
969 dasd_stats_array(m, data->dasd_io_time2ps);
970 seq_printf(m, "histogram_time_irq_to_end ");
971 dasd_stats_array(m, data->dasd_io_time3);
972 seq_printf(m, "histogram_ccw_queue_length ");
973 dasd_stats_array(m, data->dasd_io_nr_req);
974 seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs);
975 seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects);
976 seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias);
977 seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm);
978 seq_printf(m, "histogram_read_sectors ");
979 dasd_stats_array(m, data->dasd_read_secs);
980 seq_printf(m, "histogram_read_times ");
981 dasd_stats_array(m, data->dasd_read_times);
982 seq_printf(m, "histogram_read_time_build_to_ssch ");
983 dasd_stats_array(m, data->dasd_read_time1);
984 seq_printf(m, "histogram_read_time_ssch_to_irq ");
985 dasd_stats_array(m, data->dasd_read_time2);
986 seq_printf(m, "histogram_read_time_irq_to_end ");
987 dasd_stats_array(m, data->dasd_read_time3);
988 seq_printf(m, "histogram_read_ccw_queue_length ");
989 dasd_stats_array(m, data->dasd_read_nr_req);
990 }
991
dasd_stats_show(struct seq_file * m,void * v)992 static int dasd_stats_show(struct seq_file *m, void *v)
993 {
994 struct dasd_profile *profile;
995 struct dasd_profile_info *data;
996
997 profile = m->private;
998 spin_lock_bh(&profile->lock);
999 data = profile->data;
1000 if (!data) {
1001 spin_unlock_bh(&profile->lock);
1002 seq_printf(m, "disabled\n");
1003 return 0;
1004 }
1005 dasd_stats_seq_print(m, data);
1006 spin_unlock_bh(&profile->lock);
1007 return 0;
1008 }
1009
dasd_stats_open(struct inode * inode,struct file * file)1010 static int dasd_stats_open(struct inode *inode, struct file *file)
1011 {
1012 struct dasd_profile *profile = inode->i_private;
1013 return single_open(file, dasd_stats_show, profile);
1014 }
1015
1016 static const struct file_operations dasd_stats_raw_fops = {
1017 .owner = THIS_MODULE,
1018 .open = dasd_stats_open,
1019 .read = seq_read,
1020 .llseek = seq_lseek,
1021 .release = single_release,
1022 .write = dasd_stats_write,
1023 };
1024
dasd_stats_global_write(struct file * file,const char __user * user_buf,size_t user_len,loff_t * pos)1025 static ssize_t dasd_stats_global_write(struct file *file,
1026 const char __user *user_buf,
1027 size_t user_len, loff_t *pos)
1028 {
1029 char *buffer, *str;
1030 ssize_t rc;
1031
1032 if (user_len > 65536)
1033 user_len = 65536;
1034 buffer = dasd_get_user_string(user_buf, user_len);
1035 if (IS_ERR(buffer))
1036 return PTR_ERR(buffer);
1037 str = skip_spaces(buffer);
1038 rc = user_len;
1039 if (strncmp(str, "reset", 5) == 0) {
1040 dasd_global_profile_reset();
1041 } else if (strncmp(str, "on", 2) == 0) {
1042 dasd_global_profile_reset();
1043 dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY;
1044 } else if (strncmp(str, "off", 3) == 0) {
1045 dasd_global_profile_level = DASD_PROFILE_OFF;
1046 } else
1047 rc = -EINVAL;
1048 vfree(buffer);
1049 return rc;
1050 }
1051
dasd_stats_global_show(struct seq_file * m,void * v)1052 static int dasd_stats_global_show(struct seq_file *m, void *v)
1053 {
1054 if (!dasd_global_profile_level) {
1055 seq_printf(m, "disabled\n");
1056 return 0;
1057 }
1058 dasd_stats_seq_print(m, &dasd_global_profile_data);
1059 return 0;
1060 }
1061
dasd_stats_global_open(struct inode * inode,struct file * file)1062 static int dasd_stats_global_open(struct inode *inode, struct file *file)
1063 {
1064 return single_open(file, dasd_stats_global_show, NULL);
1065 }
1066
1067 static const struct file_operations dasd_stats_global_fops = {
1068 .owner = THIS_MODULE,
1069 .open = dasd_stats_global_open,
1070 .read = seq_read,
1071 .llseek = seq_lseek,
1072 .release = single_release,
1073 .write = dasd_stats_global_write,
1074 };
1075
dasd_profile_init(struct dasd_profile * profile,struct dentry * base_dentry)1076 static void dasd_profile_init(struct dasd_profile *profile,
1077 struct dentry *base_dentry)
1078 {
1079 umode_t mode;
1080 struct dentry *pde;
1081
1082 if (!base_dentry)
1083 return;
1084 profile->dentry = NULL;
1085 profile->data = NULL;
1086 mode = (S_IRUSR | S_IWUSR | S_IFREG);
1087 pde = debugfs_create_file("statistics", mode, base_dentry,
1088 profile, &dasd_stats_raw_fops);
1089 if (pde && !IS_ERR(pde))
1090 profile->dentry = pde;
1091 return;
1092 }
1093
dasd_profile_exit(struct dasd_profile * profile)1094 static void dasd_profile_exit(struct dasd_profile *profile)
1095 {
1096 dasd_profile_off(profile);
1097 if (profile->dentry) {
1098 debugfs_remove(profile->dentry);
1099 profile->dentry = NULL;
1100 }
1101 }
1102
dasd_statistics_removeroot(void)1103 static void dasd_statistics_removeroot(void)
1104 {
1105 dasd_global_profile_level = DASD_PROFILE_OFF;
1106 if (dasd_global_profile_dentry) {
1107 debugfs_remove(dasd_global_profile_dentry);
1108 dasd_global_profile_dentry = NULL;
1109 }
1110 if (dasd_debugfs_global_entry)
1111 debugfs_remove(dasd_debugfs_global_entry);
1112 if (dasd_debugfs_root_entry)
1113 debugfs_remove(dasd_debugfs_root_entry);
1114 }
1115
dasd_statistics_createroot(void)1116 static void dasd_statistics_createroot(void)
1117 {
1118 umode_t mode;
1119 struct dentry *pde;
1120
1121 dasd_debugfs_root_entry = NULL;
1122 dasd_debugfs_global_entry = NULL;
1123 dasd_global_profile_dentry = NULL;
1124 pde = debugfs_create_dir("dasd", NULL);
1125 if (!pde || IS_ERR(pde))
1126 goto error;
1127 dasd_debugfs_root_entry = pde;
1128 pde = debugfs_create_dir("global", dasd_debugfs_root_entry);
1129 if (!pde || IS_ERR(pde))
1130 goto error;
1131 dasd_debugfs_global_entry = pde;
1132
1133 mode = (S_IRUSR | S_IWUSR | S_IFREG);
1134 pde = debugfs_create_file("statistics", mode, dasd_debugfs_global_entry,
1135 NULL, &dasd_stats_global_fops);
1136 if (!pde || IS_ERR(pde))
1137 goto error;
1138 dasd_global_profile_dentry = pde;
1139 return;
1140
1141 error:
1142 DBF_EVENT(DBF_ERR, "%s",
1143 "Creation of the dasd debugfs interface failed");
1144 dasd_statistics_removeroot();
1145 return;
1146 }
1147
1148 #else
1149 #define dasd_profile_start(block, cqr, req) do {} while (0)
1150 #define dasd_profile_end(block, cqr, req) do {} while (0)
1151
dasd_statistics_createroot(void)1152 static void dasd_statistics_createroot(void)
1153 {
1154 return;
1155 }
1156
dasd_statistics_removeroot(void)1157 static void dasd_statistics_removeroot(void)
1158 {
1159 return;
1160 }
1161
dasd_stats_generic_show(struct seq_file * m,void * v)1162 int dasd_stats_generic_show(struct seq_file *m, void *v)
1163 {
1164 seq_printf(m, "Statistics are not activated in this kernel\n");
1165 return 0;
1166 }
1167
dasd_profile_init(struct dasd_profile * profile,struct dentry * base_dentry)1168 static void dasd_profile_init(struct dasd_profile *profile,
1169 struct dentry *base_dentry)
1170 {
1171 return;
1172 }
1173
dasd_profile_exit(struct dasd_profile * profile)1174 static void dasd_profile_exit(struct dasd_profile *profile)
1175 {
1176 return;
1177 }
1178
dasd_profile_on(struct dasd_profile * profile)1179 int dasd_profile_on(struct dasd_profile *profile)
1180 {
1181 return 0;
1182 }
1183
1184 #endif /* CONFIG_DASD_PROFILE */
1185
1186 /*
1187 * Allocate memory for a channel program with 'cplength' channel
1188 * command words and 'datasize' additional space. There are two
1189 * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed
1190 * memory and 2) dasd_smalloc_request uses the static ccw memory
1191 * that gets allocated for each device.
1192 */
dasd_kmalloc_request(int magic,int cplength,int datasize,struct dasd_device * device)1193 struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength,
1194 int datasize,
1195 struct dasd_device *device)
1196 {
1197 struct dasd_ccw_req *cqr;
1198
1199 /* Sanity checks */
1200 BUG_ON(datasize > PAGE_SIZE ||
1201 (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
1202
1203 cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
1204 if (cqr == NULL)
1205 return ERR_PTR(-ENOMEM);
1206 cqr->cpaddr = NULL;
1207 if (cplength > 0) {
1208 cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
1209 GFP_ATOMIC | GFP_DMA);
1210 if (cqr->cpaddr == NULL) {
1211 kfree(cqr);
1212 return ERR_PTR(-ENOMEM);
1213 }
1214 }
1215 cqr->data = NULL;
1216 if (datasize > 0) {
1217 cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA);
1218 if (cqr->data == NULL) {
1219 kfree(cqr->cpaddr);
1220 kfree(cqr);
1221 return ERR_PTR(-ENOMEM);
1222 }
1223 }
1224 cqr->magic = magic;
1225 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1226 dasd_get_device(device);
1227 return cqr;
1228 }
1229
dasd_smalloc_request(int magic,int cplength,int datasize,struct dasd_device * device)1230 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength,
1231 int datasize,
1232 struct dasd_device *device)
1233 {
1234 unsigned long flags;
1235 struct dasd_ccw_req *cqr;
1236 char *data;
1237 int size;
1238
1239 size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
1240 if (cplength > 0)
1241 size += cplength * sizeof(struct ccw1);
1242 if (datasize > 0)
1243 size += datasize;
1244 spin_lock_irqsave(&device->mem_lock, flags);
1245 cqr = (struct dasd_ccw_req *)
1246 dasd_alloc_chunk(&device->ccw_chunks, size);
1247 spin_unlock_irqrestore(&device->mem_lock, flags);
1248 if (cqr == NULL)
1249 return ERR_PTR(-ENOMEM);
1250 memset(cqr, 0, sizeof(struct dasd_ccw_req));
1251 data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
1252 cqr->cpaddr = NULL;
1253 if (cplength > 0) {
1254 cqr->cpaddr = (struct ccw1 *) data;
1255 data += cplength*sizeof(struct ccw1);
1256 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
1257 }
1258 cqr->data = NULL;
1259 if (datasize > 0) {
1260 cqr->data = data;
1261 memset(cqr->data, 0, datasize);
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
1269 /*
1270 * Free memory of a channel program. This function needs to free all the
1271 * idal lists that might have been created by dasd_set_cda and the
1272 * struct dasd_ccw_req itself.
1273 */
dasd_kfree_request(struct dasd_ccw_req * cqr,struct dasd_device * device)1274 void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1275 {
1276 #ifdef CONFIG_64BIT
1277 struct ccw1 *ccw;
1278
1279 /* Clear any idals used for the request. */
1280 ccw = cqr->cpaddr;
1281 do {
1282 clear_normalized_cda(ccw);
1283 } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
1284 #endif
1285 kfree(cqr->cpaddr);
1286 kfree(cqr->data);
1287 kfree(cqr);
1288 dasd_put_device(device);
1289 }
1290
dasd_sfree_request(struct dasd_ccw_req * cqr,struct dasd_device * device)1291 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1292 {
1293 unsigned long flags;
1294
1295 spin_lock_irqsave(&device->mem_lock, flags);
1296 dasd_free_chunk(&device->ccw_chunks, cqr);
1297 spin_unlock_irqrestore(&device->mem_lock, flags);
1298 dasd_put_device(device);
1299 }
1300
1301 /*
1302 * Check discipline magic in cqr.
1303 */
dasd_check_cqr(struct dasd_ccw_req * cqr)1304 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
1305 {
1306 struct dasd_device *device;
1307
1308 if (cqr == NULL)
1309 return -EINVAL;
1310 device = cqr->startdev;
1311 if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
1312 DBF_DEV_EVENT(DBF_WARNING, device,
1313 " dasd_ccw_req 0x%08x magic doesn't match"
1314 " discipline 0x%08x",
1315 cqr->magic,
1316 *(unsigned int *) device->discipline->name);
1317 return -EINVAL;
1318 }
1319 return 0;
1320 }
1321
1322 /*
1323 * Terminate the current i/o and set the request to clear_pending.
1324 * Timer keeps device runnig.
1325 * ccw_device_clear can fail if the i/o subsystem
1326 * is in a bad mood.
1327 */
dasd_term_IO(struct dasd_ccw_req * cqr)1328 int dasd_term_IO(struct dasd_ccw_req *cqr)
1329 {
1330 struct dasd_device *device;
1331 int retries, rc;
1332 char errorstring[ERRORLENGTH];
1333
1334 /* Check the cqr */
1335 rc = dasd_check_cqr(cqr);
1336 if (rc)
1337 return rc;
1338 retries = 0;
1339 device = (struct dasd_device *) cqr->startdev;
1340 while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
1341 rc = ccw_device_clear(device->cdev, (long) cqr);
1342 switch (rc) {
1343 case 0: /* termination successful */
1344 cqr->status = DASD_CQR_CLEAR_PENDING;
1345 cqr->stopclk = get_clock();
1346 cqr->starttime = 0;
1347 DBF_DEV_EVENT(DBF_DEBUG, device,
1348 "terminate cqr %p successful",
1349 cqr);
1350 break;
1351 case -ENODEV:
1352 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1353 "device gone, retry");
1354 break;
1355 case -EIO:
1356 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1357 "I/O error, retry");
1358 break;
1359 case -EINVAL:
1360 case -EBUSY:
1361 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1362 "device busy, retry later");
1363 break;
1364 default:
1365 /* internal error 10 - unknown rc*/
1366 snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
1367 dev_err(&device->cdev->dev, "An error occurred in the "
1368 "DASD device driver, reason=%s\n", errorstring);
1369 BUG();
1370 break;
1371 }
1372 retries++;
1373 }
1374 dasd_schedule_device_bh(device);
1375 return rc;
1376 }
1377
1378 /*
1379 * Start the i/o. This start_IO can fail if the channel is really busy.
1380 * In that case set up a timer to start the request later.
1381 */
dasd_start_IO(struct dasd_ccw_req * cqr)1382 int dasd_start_IO(struct dasd_ccw_req *cqr)
1383 {
1384 struct dasd_device *device;
1385 int rc;
1386 char errorstring[ERRORLENGTH];
1387
1388 /* Check the cqr */
1389 rc = dasd_check_cqr(cqr);
1390 if (rc) {
1391 cqr->intrc = rc;
1392 return rc;
1393 }
1394 device = (struct dasd_device *) cqr->startdev;
1395 if (((cqr->block &&
1396 test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) ||
1397 test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) &&
1398 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
1399 DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p "
1400 "because of stolen lock", cqr);
1401 cqr->status = DASD_CQR_ERROR;
1402 cqr->intrc = -EPERM;
1403 return -EPERM;
1404 }
1405 if (cqr->retries < 0) {
1406 /* internal error 14 - start_IO run out of retries */
1407 sprintf(errorstring, "14 %p", cqr);
1408 dev_err(&device->cdev->dev, "An error occurred in the DASD "
1409 "device driver, reason=%s\n", errorstring);
1410 cqr->status = DASD_CQR_ERROR;
1411 return -EIO;
1412 }
1413 cqr->startclk = get_clock();
1414 cqr->starttime = jiffies;
1415 cqr->retries--;
1416 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1417 cqr->lpm &= device->path_data.opm;
1418 if (!cqr->lpm)
1419 cqr->lpm = device->path_data.opm;
1420 }
1421 if (cqr->cpmode == 1) {
1422 rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
1423 (long) cqr, cqr->lpm);
1424 } else {
1425 rc = ccw_device_start(device->cdev, cqr->cpaddr,
1426 (long) cqr, cqr->lpm, 0);
1427 }
1428 switch (rc) {
1429 case 0:
1430 cqr->status = DASD_CQR_IN_IO;
1431 break;
1432 case -EBUSY:
1433 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1434 "start_IO: device busy, retry later");
1435 break;
1436 case -ETIMEDOUT:
1437 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1438 "start_IO: request timeout, retry later");
1439 break;
1440 case -EACCES:
1441 /* -EACCES indicates that the request used only a subset of the
1442 * available paths and all these paths are gone. If the lpm of
1443 * this request was only a subset of the opm (e.g. the ppm) then
1444 * we just do a retry with all available paths.
1445 * If we already use the full opm, something is amiss, and we
1446 * need a full path verification.
1447 */
1448 if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1449 DBF_DEV_EVENT(DBF_WARNING, device,
1450 "start_IO: selected paths gone (%x)",
1451 cqr->lpm);
1452 } else if (cqr->lpm != device->path_data.opm) {
1453 cqr->lpm = device->path_data.opm;
1454 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
1455 "start_IO: selected paths gone,"
1456 " retry on all paths");
1457 } else {
1458 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1459 "start_IO: all paths in opm gone,"
1460 " do path verification");
1461 dasd_generic_last_path_gone(device);
1462 device->path_data.opm = 0;
1463 device->path_data.ppm = 0;
1464 device->path_data.npm = 0;
1465 device->path_data.tbvpm =
1466 ccw_device_get_path_mask(device->cdev);
1467 }
1468 break;
1469 case -ENODEV:
1470 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1471 "start_IO: -ENODEV device gone, retry");
1472 break;
1473 case -EIO:
1474 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1475 "start_IO: -EIO device gone, retry");
1476 break;
1477 case -EINVAL:
1478 /* most likely caused in power management context */
1479 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1480 "start_IO: -EINVAL device currently "
1481 "not accessible");
1482 break;
1483 default:
1484 /* internal error 11 - unknown rc */
1485 snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
1486 dev_err(&device->cdev->dev,
1487 "An error occurred in the DASD device driver, "
1488 "reason=%s\n", errorstring);
1489 BUG();
1490 break;
1491 }
1492 cqr->intrc = rc;
1493 return rc;
1494 }
1495
1496 /*
1497 * Timeout function for dasd devices. This is used for different purposes
1498 * 1) missing interrupt handler for normal operation
1499 * 2) delayed start of request where start_IO failed with -EBUSY
1500 * 3) timeout for missing state change interrupts
1501 * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
1502 * DASD_CQR_QUEUED for 2) and 3).
1503 */
dasd_device_timeout(unsigned long ptr)1504 static void dasd_device_timeout(unsigned long ptr)
1505 {
1506 unsigned long flags;
1507 struct dasd_device *device;
1508
1509 device = (struct dasd_device *) ptr;
1510 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1511 /* re-activate request queue */
1512 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1513 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1514 dasd_schedule_device_bh(device);
1515 }
1516
1517 /*
1518 * Setup timeout for a device in jiffies.
1519 */
dasd_device_set_timer(struct dasd_device * device,int expires)1520 void dasd_device_set_timer(struct dasd_device *device, int expires)
1521 {
1522 if (expires == 0)
1523 del_timer(&device->timer);
1524 else
1525 mod_timer(&device->timer, jiffies + expires);
1526 }
1527
1528 /*
1529 * Clear timeout for a device.
1530 */
dasd_device_clear_timer(struct dasd_device * device)1531 void dasd_device_clear_timer(struct dasd_device *device)
1532 {
1533 del_timer(&device->timer);
1534 }
1535
dasd_handle_killed_request(struct ccw_device * cdev,unsigned long intparm)1536 static void dasd_handle_killed_request(struct ccw_device *cdev,
1537 unsigned long intparm)
1538 {
1539 struct dasd_ccw_req *cqr;
1540 struct dasd_device *device;
1541
1542 if (!intparm)
1543 return;
1544 cqr = (struct dasd_ccw_req *) intparm;
1545 if (cqr->status != DASD_CQR_IN_IO) {
1546 DBF_EVENT_DEVID(DBF_DEBUG, cdev,
1547 "invalid status in handle_killed_request: "
1548 "%02x", cqr->status);
1549 return;
1550 }
1551
1552 device = dasd_device_from_cdev_locked(cdev);
1553 if (IS_ERR(device)) {
1554 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1555 "unable to get device from cdev");
1556 return;
1557 }
1558
1559 if (!cqr->startdev ||
1560 device != cqr->startdev ||
1561 strncmp(cqr->startdev->discipline->ebcname,
1562 (char *) &cqr->magic, 4)) {
1563 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1564 "invalid device in request");
1565 dasd_put_device(device);
1566 return;
1567 }
1568
1569 /* Schedule request to be retried. */
1570 cqr->status = DASD_CQR_QUEUED;
1571
1572 dasd_device_clear_timer(device);
1573 dasd_schedule_device_bh(device);
1574 dasd_put_device(device);
1575 }
1576
dasd_generic_handle_state_change(struct dasd_device * device)1577 void dasd_generic_handle_state_change(struct dasd_device *device)
1578 {
1579 /* First of all start sense subsystem status request. */
1580 dasd_eer_snss(device);
1581
1582 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1583 dasd_schedule_device_bh(device);
1584 if (device->block)
1585 dasd_schedule_block_bh(device->block);
1586 }
1587
1588 /*
1589 * Interrupt handler for "normal" ssch-io based dasd devices.
1590 */
dasd_int_handler(struct ccw_device * cdev,unsigned long intparm,struct irb * irb)1591 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
1592 struct irb *irb)
1593 {
1594 struct dasd_ccw_req *cqr, *next;
1595 struct dasd_device *device;
1596 unsigned long long now;
1597 int expires;
1598
1599 if (IS_ERR(irb)) {
1600 switch (PTR_ERR(irb)) {
1601 case -EIO:
1602 break;
1603 case -ETIMEDOUT:
1604 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1605 "request timed out\n", __func__);
1606 break;
1607 default:
1608 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1609 "unknown error %ld\n", __func__,
1610 PTR_ERR(irb));
1611 }
1612 dasd_handle_killed_request(cdev, intparm);
1613 return;
1614 }
1615
1616 now = get_clock();
1617 cqr = (struct dasd_ccw_req *) intparm;
1618 /* check for conditions that should be handled immediately */
1619 if (!cqr ||
1620 !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1621 scsw_cstat(&irb->scsw) == 0)) {
1622 if (cqr)
1623 memcpy(&cqr->irb, irb, sizeof(*irb));
1624 device = dasd_device_from_cdev_locked(cdev);
1625 if (IS_ERR(device))
1626 return;
1627 /* ignore unsolicited interrupts for DIAG discipline */
1628 if (device->discipline == dasd_diag_discipline_pointer) {
1629 dasd_put_device(device);
1630 return;
1631 }
1632 device->discipline->dump_sense_dbf(device, irb, "int");
1633 if (device->features & DASD_FEATURE_ERPLOG)
1634 device->discipline->dump_sense(device, cqr, irb);
1635 device->discipline->check_for_device_change(device, cqr, irb);
1636 dasd_put_device(device);
1637 }
1638 if (!cqr)
1639 return;
1640
1641 device = (struct dasd_device *) cqr->startdev;
1642 if (!device ||
1643 strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
1644 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1645 "invalid device in request");
1646 return;
1647 }
1648
1649 /* Check for clear pending */
1650 if (cqr->status == DASD_CQR_CLEAR_PENDING &&
1651 scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
1652 cqr->status = DASD_CQR_CLEARED;
1653 dasd_device_clear_timer(device);
1654 wake_up(&dasd_flush_wq);
1655 dasd_schedule_device_bh(device);
1656 return;
1657 }
1658
1659 /* check status - the request might have been killed by dyn detach */
1660 if (cqr->status != DASD_CQR_IN_IO) {
1661 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
1662 "status %02x", dev_name(&cdev->dev), cqr->status);
1663 return;
1664 }
1665
1666 next = NULL;
1667 expires = 0;
1668 if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1669 scsw_cstat(&irb->scsw) == 0) {
1670 /* request was completed successfully */
1671 cqr->status = DASD_CQR_SUCCESS;
1672 cqr->stopclk = now;
1673 /* Start first request on queue if possible -> fast_io. */
1674 if (cqr->devlist.next != &device->ccw_queue) {
1675 next = list_entry(cqr->devlist.next,
1676 struct dasd_ccw_req, devlist);
1677 }
1678 } else { /* error */
1679 /*
1680 * If we don't want complex ERP for this request, then just
1681 * reset this and retry it in the fastpath
1682 */
1683 if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
1684 cqr->retries > 0) {
1685 if (cqr->lpm == device->path_data.opm)
1686 DBF_DEV_EVENT(DBF_DEBUG, device,
1687 "default ERP in fastpath "
1688 "(%i retries left)",
1689 cqr->retries);
1690 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))
1691 cqr->lpm = device->path_data.opm;
1692 cqr->status = DASD_CQR_QUEUED;
1693 next = cqr;
1694 } else
1695 cqr->status = DASD_CQR_ERROR;
1696 }
1697 if (next && (next->status == DASD_CQR_QUEUED) &&
1698 (!device->stopped)) {
1699 if (device->discipline->start_IO(next) == 0)
1700 expires = next->expires;
1701 }
1702 if (expires != 0)
1703 dasd_device_set_timer(device, expires);
1704 else
1705 dasd_device_clear_timer(device);
1706 dasd_schedule_device_bh(device);
1707 }
1708
dasd_generic_uc_handler(struct ccw_device * cdev,struct irb * irb)1709 enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb)
1710 {
1711 struct dasd_device *device;
1712
1713 device = dasd_device_from_cdev_locked(cdev);
1714
1715 if (IS_ERR(device))
1716 goto out;
1717 if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
1718 device->state != device->target ||
1719 !device->discipline->check_for_device_change){
1720 dasd_put_device(device);
1721 goto out;
1722 }
1723 if (device->discipline->dump_sense_dbf)
1724 device->discipline->dump_sense_dbf(device, irb, "uc");
1725 device->discipline->check_for_device_change(device, NULL, irb);
1726 dasd_put_device(device);
1727 out:
1728 return UC_TODO_RETRY;
1729 }
1730 EXPORT_SYMBOL_GPL(dasd_generic_uc_handler);
1731
1732 /*
1733 * If we have an error on a dasd_block layer request then we cancel
1734 * and return all further requests from the same dasd_block as well.
1735 */
__dasd_device_recovery(struct dasd_device * device,struct dasd_ccw_req * ref_cqr)1736 static void __dasd_device_recovery(struct dasd_device *device,
1737 struct dasd_ccw_req *ref_cqr)
1738 {
1739 struct list_head *l, *n;
1740 struct dasd_ccw_req *cqr;
1741
1742 /*
1743 * only requeue request that came from the dasd_block layer
1744 */
1745 if (!ref_cqr->block)
1746 return;
1747
1748 list_for_each_safe(l, n, &device->ccw_queue) {
1749 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1750 if (cqr->status == DASD_CQR_QUEUED &&
1751 ref_cqr->block == cqr->block) {
1752 cqr->status = DASD_CQR_CLEARED;
1753 }
1754 }
1755 };
1756
1757 /*
1758 * Remove those ccw requests from the queue that need to be returned
1759 * to the upper layer.
1760 */
__dasd_device_process_ccw_queue(struct dasd_device * device,struct list_head * final_queue)1761 static void __dasd_device_process_ccw_queue(struct dasd_device *device,
1762 struct list_head *final_queue)
1763 {
1764 struct list_head *l, *n;
1765 struct dasd_ccw_req *cqr;
1766
1767 /* Process request with final status. */
1768 list_for_each_safe(l, n, &device->ccw_queue) {
1769 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1770
1771 /* Stop list processing at the first non-final request. */
1772 if (cqr->status == DASD_CQR_QUEUED ||
1773 cqr->status == DASD_CQR_IN_IO ||
1774 cqr->status == DASD_CQR_CLEAR_PENDING)
1775 break;
1776 if (cqr->status == DASD_CQR_ERROR) {
1777 __dasd_device_recovery(device, cqr);
1778 }
1779 /* Rechain finished requests to final queue */
1780 list_move_tail(&cqr->devlist, final_queue);
1781 }
1782 }
1783
1784 /*
1785 * the cqrs from the final queue are returned to the upper layer
1786 * by setting a dasd_block state and calling the callback function
1787 */
__dasd_device_process_final_queue(struct dasd_device * device,struct list_head * final_queue)1788 static void __dasd_device_process_final_queue(struct dasd_device *device,
1789 struct list_head *final_queue)
1790 {
1791 struct list_head *l, *n;
1792 struct dasd_ccw_req *cqr;
1793 struct dasd_block *block;
1794 void (*callback)(struct dasd_ccw_req *, void *data);
1795 void *callback_data;
1796 char errorstring[ERRORLENGTH];
1797
1798 list_for_each_safe(l, n, final_queue) {
1799 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1800 list_del_init(&cqr->devlist);
1801 block = cqr->block;
1802 callback = cqr->callback;
1803 callback_data = cqr->callback_data;
1804 if (block)
1805 spin_lock_bh(&block->queue_lock);
1806 switch (cqr->status) {
1807 case DASD_CQR_SUCCESS:
1808 cqr->status = DASD_CQR_DONE;
1809 break;
1810 case DASD_CQR_ERROR:
1811 cqr->status = DASD_CQR_NEED_ERP;
1812 break;
1813 case DASD_CQR_CLEARED:
1814 cqr->status = DASD_CQR_TERMINATED;
1815 break;
1816 default:
1817 /* internal error 12 - wrong cqr status*/
1818 snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
1819 dev_err(&device->cdev->dev,
1820 "An error occurred in the DASD device driver, "
1821 "reason=%s\n", errorstring);
1822 BUG();
1823 }
1824 if (cqr->callback != NULL)
1825 (callback)(cqr, callback_data);
1826 if (block)
1827 spin_unlock_bh(&block->queue_lock);
1828 }
1829 }
1830
1831 /*
1832 * Take a look at the first request on the ccw queue and check
1833 * if it reached its expire time. If so, terminate the IO.
1834 */
__dasd_device_check_expire(struct dasd_device * device)1835 static void __dasd_device_check_expire(struct dasd_device *device)
1836 {
1837 struct dasd_ccw_req *cqr;
1838
1839 if (list_empty(&device->ccw_queue))
1840 return;
1841 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1842 if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
1843 (time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
1844 if (device->discipline->term_IO(cqr) != 0) {
1845 /* Hmpf, try again in 5 sec */
1846 dev_err(&device->cdev->dev,
1847 "cqr %p timed out (%lus) but cannot be "
1848 "ended, retrying in 5 s\n",
1849 cqr, (cqr->expires/HZ));
1850 cqr->expires += 5*HZ;
1851 dasd_device_set_timer(device, 5*HZ);
1852 } else {
1853 dev_err(&device->cdev->dev,
1854 "cqr %p timed out (%lus), %i retries "
1855 "remaining\n", cqr, (cqr->expires/HZ),
1856 cqr->retries);
1857 }
1858 }
1859 }
1860
1861 /*
1862 * Take a look at the first request on the ccw queue and check
1863 * if it needs to be started.
1864 */
__dasd_device_start_head(struct dasd_device * device)1865 static void __dasd_device_start_head(struct dasd_device *device)
1866 {
1867 struct dasd_ccw_req *cqr;
1868 int rc;
1869
1870 if (list_empty(&device->ccw_queue))
1871 return;
1872 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1873 if (cqr->status != DASD_CQR_QUEUED)
1874 return;
1875 /* when device is stopped, return request to previous layer
1876 * exception: only the disconnect or unresumed bits are set and the
1877 * cqr is a path verification request
1878 */
1879 if (device->stopped &&
1880 !(!(device->stopped & ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
1881 && test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))) {
1882 cqr->intrc = -EAGAIN;
1883 cqr->status = DASD_CQR_CLEARED;
1884 dasd_schedule_device_bh(device);
1885 return;
1886 }
1887
1888 rc = device->discipline->start_IO(cqr);
1889 if (rc == 0)
1890 dasd_device_set_timer(device, cqr->expires);
1891 else if (rc == -EACCES) {
1892 dasd_schedule_device_bh(device);
1893 } else
1894 /* Hmpf, try again in 1/2 sec */
1895 dasd_device_set_timer(device, 50);
1896 }
1897
__dasd_device_check_path_events(struct dasd_device * device)1898 static void __dasd_device_check_path_events(struct dasd_device *device)
1899 {
1900 int rc;
1901
1902 if (device->path_data.tbvpm) {
1903 if (device->stopped & ~(DASD_STOPPED_DC_WAIT |
1904 DASD_UNRESUMED_PM))
1905 return;
1906 rc = device->discipline->verify_path(
1907 device, device->path_data.tbvpm);
1908 if (rc)
1909 dasd_device_set_timer(device, 50);
1910 else
1911 device->path_data.tbvpm = 0;
1912 }
1913 };
1914
1915 /*
1916 * Go through all request on the dasd_device request queue,
1917 * terminate them on the cdev if necessary, and return them to the
1918 * submitting layer via callback.
1919 * Note:
1920 * Make sure that all 'submitting layers' still exist when
1921 * this function is called!. In other words, when 'device' is a base
1922 * device then all block layer requests must have been removed before
1923 * via dasd_flush_block_queue.
1924 */
dasd_flush_device_queue(struct dasd_device * device)1925 int dasd_flush_device_queue(struct dasd_device *device)
1926 {
1927 struct dasd_ccw_req *cqr, *n;
1928 int rc;
1929 struct list_head flush_queue;
1930
1931 INIT_LIST_HEAD(&flush_queue);
1932 spin_lock_irq(get_ccwdev_lock(device->cdev));
1933 rc = 0;
1934 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
1935 /* Check status and move request to flush_queue */
1936 switch (cqr->status) {
1937 case DASD_CQR_IN_IO:
1938 rc = device->discipline->term_IO(cqr);
1939 if (rc) {
1940 /* unable to terminate requeust */
1941 dev_err(&device->cdev->dev,
1942 "Flushing the DASD request queue "
1943 "failed for request %p\n", cqr);
1944 /* stop flush processing */
1945 goto finished;
1946 }
1947 break;
1948 case DASD_CQR_QUEUED:
1949 cqr->stopclk = get_clock();
1950 cqr->status = DASD_CQR_CLEARED;
1951 break;
1952 default: /* no need to modify the others */
1953 break;
1954 }
1955 list_move_tail(&cqr->devlist, &flush_queue);
1956 }
1957 finished:
1958 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1959 /*
1960 * After this point all requests must be in state CLEAR_PENDING,
1961 * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
1962 * one of the others.
1963 */
1964 list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
1965 wait_event(dasd_flush_wq,
1966 (cqr->status != DASD_CQR_CLEAR_PENDING));
1967 /*
1968 * Now set each request back to TERMINATED, DONE or NEED_ERP
1969 * and call the callback function of flushed requests
1970 */
1971 __dasd_device_process_final_queue(device, &flush_queue);
1972 return rc;
1973 }
1974
1975 /*
1976 * Acquire the device lock and process queues for the device.
1977 */
dasd_device_tasklet(struct dasd_device * device)1978 static void dasd_device_tasklet(struct dasd_device *device)
1979 {
1980 struct list_head final_queue;
1981
1982 atomic_set (&device->tasklet_scheduled, 0);
1983 INIT_LIST_HEAD(&final_queue);
1984 spin_lock_irq(get_ccwdev_lock(device->cdev));
1985 /* Check expire time of first request on the ccw queue. */
1986 __dasd_device_check_expire(device);
1987 /* find final requests on ccw queue */
1988 __dasd_device_process_ccw_queue(device, &final_queue);
1989 __dasd_device_check_path_events(device);
1990 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1991 /* Now call the callback function of requests with final status */
1992 __dasd_device_process_final_queue(device, &final_queue);
1993 spin_lock_irq(get_ccwdev_lock(device->cdev));
1994 /* Now check if the head of the ccw queue needs to be started. */
1995 __dasd_device_start_head(device);
1996 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1997 dasd_put_device(device);
1998 }
1999
2000 /*
2001 * Schedules a call to dasd_tasklet over the device tasklet.
2002 */
dasd_schedule_device_bh(struct dasd_device * device)2003 void dasd_schedule_device_bh(struct dasd_device *device)
2004 {
2005 /* Protect against rescheduling. */
2006 if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
2007 return;
2008 dasd_get_device(device);
2009 tasklet_hi_schedule(&device->tasklet);
2010 }
2011
dasd_device_set_stop_bits(struct dasd_device * device,int bits)2012 void dasd_device_set_stop_bits(struct dasd_device *device, int bits)
2013 {
2014 device->stopped |= bits;
2015 }
2016 EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits);
2017
dasd_device_remove_stop_bits(struct dasd_device * device,int bits)2018 void dasd_device_remove_stop_bits(struct dasd_device *device, int bits)
2019 {
2020 device->stopped &= ~bits;
2021 if (!device->stopped)
2022 wake_up(&generic_waitq);
2023 }
2024 EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits);
2025
2026 /*
2027 * Queue a request to the head of the device ccw_queue.
2028 * Start the I/O if possible.
2029 */
dasd_add_request_head(struct dasd_ccw_req * cqr)2030 void dasd_add_request_head(struct dasd_ccw_req *cqr)
2031 {
2032 struct dasd_device *device;
2033 unsigned long flags;
2034
2035 device = cqr->startdev;
2036 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2037 cqr->status = DASD_CQR_QUEUED;
2038 list_add(&cqr->devlist, &device->ccw_queue);
2039 /* let the bh start the request to keep them in order */
2040 dasd_schedule_device_bh(device);
2041 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2042 }
2043
2044 /*
2045 * Queue a request to the tail of the device ccw_queue.
2046 * Start the I/O if possible.
2047 */
dasd_add_request_tail(struct dasd_ccw_req * cqr)2048 void dasd_add_request_tail(struct dasd_ccw_req *cqr)
2049 {
2050 struct dasd_device *device;
2051 unsigned long flags;
2052
2053 device = cqr->startdev;
2054 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2055 cqr->status = DASD_CQR_QUEUED;
2056 list_add_tail(&cqr->devlist, &device->ccw_queue);
2057 /* let the bh start the request to keep them in order */
2058 dasd_schedule_device_bh(device);
2059 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2060 }
2061
2062 /*
2063 * Wakeup helper for the 'sleep_on' functions.
2064 */
dasd_wakeup_cb(struct dasd_ccw_req * cqr,void * data)2065 void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
2066 {
2067 spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2068 cqr->callback_data = DASD_SLEEPON_END_TAG;
2069 spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2070 wake_up(&generic_waitq);
2071 }
2072 EXPORT_SYMBOL_GPL(dasd_wakeup_cb);
2073
_wait_for_wakeup(struct dasd_ccw_req * cqr)2074 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
2075 {
2076 struct dasd_device *device;
2077 int rc;
2078
2079 device = cqr->startdev;
2080 spin_lock_irq(get_ccwdev_lock(device->cdev));
2081 rc = (cqr->callback_data == DASD_SLEEPON_END_TAG);
2082 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2083 return rc;
2084 }
2085
2086 /*
2087 * checks if error recovery is necessary, returns 1 if yes, 0 otherwise.
2088 */
__dasd_sleep_on_erp(struct dasd_ccw_req * cqr)2089 static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr)
2090 {
2091 struct dasd_device *device;
2092 dasd_erp_fn_t erp_fn;
2093
2094 if (cqr->status == DASD_CQR_FILLED)
2095 return 0;
2096 device = cqr->startdev;
2097 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2098 if (cqr->status == DASD_CQR_TERMINATED) {
2099 device->discipline->handle_terminated_request(cqr);
2100 return 1;
2101 }
2102 if (cqr->status == DASD_CQR_NEED_ERP) {
2103 erp_fn = device->discipline->erp_action(cqr);
2104 erp_fn(cqr);
2105 return 1;
2106 }
2107 if (cqr->status == DASD_CQR_FAILED)
2108 dasd_log_sense(cqr, &cqr->irb);
2109 if (cqr->refers) {
2110 __dasd_process_erp(device, cqr);
2111 return 1;
2112 }
2113 }
2114 return 0;
2115 }
2116
__dasd_sleep_on_loop_condition(struct dasd_ccw_req * cqr)2117 static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr)
2118 {
2119 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2120 if (cqr->refers) /* erp is not done yet */
2121 return 1;
2122 return ((cqr->status != DASD_CQR_DONE) &&
2123 (cqr->status != DASD_CQR_FAILED));
2124 } else
2125 return (cqr->status == DASD_CQR_FILLED);
2126 }
2127
_dasd_sleep_on(struct dasd_ccw_req * maincqr,int interruptible)2128 static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
2129 {
2130 struct dasd_device *device;
2131 int rc;
2132 struct list_head ccw_queue;
2133 struct dasd_ccw_req *cqr;
2134
2135 INIT_LIST_HEAD(&ccw_queue);
2136 maincqr->status = DASD_CQR_FILLED;
2137 device = maincqr->startdev;
2138 list_add(&maincqr->blocklist, &ccw_queue);
2139 for (cqr = maincqr; __dasd_sleep_on_loop_condition(cqr);
2140 cqr = list_first_entry(&ccw_queue,
2141 struct dasd_ccw_req, blocklist)) {
2142
2143 if (__dasd_sleep_on_erp(cqr))
2144 continue;
2145 if (cqr->status != DASD_CQR_FILLED) /* could be failed */
2146 continue;
2147 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2148 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2149 cqr->status = DASD_CQR_FAILED;
2150 cqr->intrc = -EPERM;
2151 continue;
2152 }
2153 /* Non-temporary stop condition will trigger fail fast */
2154 if (device->stopped & ~DASD_STOPPED_PENDING &&
2155 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2156 (!dasd_eer_enabled(device))) {
2157 cqr->status = DASD_CQR_FAILED;
2158 continue;
2159 }
2160 /* Don't try to start requests if device is stopped */
2161 if (interruptible) {
2162 rc = wait_event_interruptible(
2163 generic_waitq, !(device->stopped));
2164 if (rc == -ERESTARTSYS) {
2165 cqr->status = DASD_CQR_FAILED;
2166 maincqr->intrc = rc;
2167 continue;
2168 }
2169 } else
2170 wait_event(generic_waitq, !(device->stopped));
2171
2172 if (!cqr->callback)
2173 cqr->callback = dasd_wakeup_cb;
2174
2175 cqr->callback_data = DASD_SLEEPON_START_TAG;
2176 dasd_add_request_tail(cqr);
2177 if (interruptible) {
2178 rc = wait_event_interruptible(
2179 generic_waitq, _wait_for_wakeup(cqr));
2180 if (rc == -ERESTARTSYS) {
2181 dasd_cancel_req(cqr);
2182 /* wait (non-interruptible) for final status */
2183 wait_event(generic_waitq,
2184 _wait_for_wakeup(cqr));
2185 cqr->status = DASD_CQR_FAILED;
2186 maincqr->intrc = rc;
2187 continue;
2188 }
2189 } else
2190 wait_event(generic_waitq, _wait_for_wakeup(cqr));
2191 }
2192
2193 maincqr->endclk = get_clock();
2194 if ((maincqr->status != DASD_CQR_DONE) &&
2195 (maincqr->intrc != -ERESTARTSYS))
2196 dasd_log_sense(maincqr, &maincqr->irb);
2197 if (maincqr->status == DASD_CQR_DONE)
2198 rc = 0;
2199 else if (maincqr->intrc)
2200 rc = maincqr->intrc;
2201 else
2202 rc = -EIO;
2203 return rc;
2204 }
2205
2206 /*
2207 * Queue a request to the tail of the device ccw_queue and wait for
2208 * it's completion.
2209 */
dasd_sleep_on(struct dasd_ccw_req * cqr)2210 int dasd_sleep_on(struct dasd_ccw_req *cqr)
2211 {
2212 return _dasd_sleep_on(cqr, 0);
2213 }
2214
2215 /*
2216 * Queue a request to the tail of the device ccw_queue and wait
2217 * interruptible for it's completion.
2218 */
dasd_sleep_on_interruptible(struct dasd_ccw_req * cqr)2219 int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
2220 {
2221 return _dasd_sleep_on(cqr, 1);
2222 }
2223
2224 /*
2225 * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
2226 * for eckd devices) the currently running request has to be terminated
2227 * and be put back to status queued, before the special request is added
2228 * to the head of the queue. Then the special request is waited on normally.
2229 */
_dasd_term_running_cqr(struct dasd_device * device)2230 static inline int _dasd_term_running_cqr(struct dasd_device *device)
2231 {
2232 struct dasd_ccw_req *cqr;
2233 int rc;
2234
2235 if (list_empty(&device->ccw_queue))
2236 return 0;
2237 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2238 rc = device->discipline->term_IO(cqr);
2239 if (!rc)
2240 /*
2241 * CQR terminated because a more important request is pending.
2242 * Undo decreasing of retry counter because this is
2243 * not an error case.
2244 */
2245 cqr->retries++;
2246 return rc;
2247 }
2248
dasd_sleep_on_immediatly(struct dasd_ccw_req * cqr)2249 int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
2250 {
2251 struct dasd_device *device;
2252 int rc;
2253
2254 device = cqr->startdev;
2255 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2256 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2257 cqr->status = DASD_CQR_FAILED;
2258 cqr->intrc = -EPERM;
2259 return -EIO;
2260 }
2261 spin_lock_irq(get_ccwdev_lock(device->cdev));
2262 rc = _dasd_term_running_cqr(device);
2263 if (rc) {
2264 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2265 return rc;
2266 }
2267 cqr->callback = dasd_wakeup_cb;
2268 cqr->callback_data = DASD_SLEEPON_START_TAG;
2269 cqr->status = DASD_CQR_QUEUED;
2270 /*
2271 * add new request as second
2272 * first the terminated cqr needs to be finished
2273 */
2274 list_add(&cqr->devlist, device->ccw_queue.next);
2275
2276 /* let the bh start the request to keep them in order */
2277 dasd_schedule_device_bh(device);
2278
2279 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2280
2281 wait_event(generic_waitq, _wait_for_wakeup(cqr));
2282
2283 if (cqr->status == DASD_CQR_DONE)
2284 rc = 0;
2285 else if (cqr->intrc)
2286 rc = cqr->intrc;
2287 else
2288 rc = -EIO;
2289 return rc;
2290 }
2291
2292 /*
2293 * Cancels a request that was started with dasd_sleep_on_req.
2294 * This is useful to timeout requests. The request will be
2295 * terminated if it is currently in i/o.
2296 * Returns 1 if the request has been terminated.
2297 * 0 if there was no need to terminate the request (not started yet)
2298 * negative error code if termination failed
2299 * Cancellation of a request is an asynchronous operation! The calling
2300 * function has to wait until the request is properly returned via callback.
2301 */
dasd_cancel_req(struct dasd_ccw_req * cqr)2302 int dasd_cancel_req(struct dasd_ccw_req *cqr)
2303 {
2304 struct dasd_device *device = cqr->startdev;
2305 unsigned long flags;
2306 int rc;
2307
2308 rc = 0;
2309 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2310 switch (cqr->status) {
2311 case DASD_CQR_QUEUED:
2312 /* request was not started - just set to cleared */
2313 cqr->status = DASD_CQR_CLEARED;
2314 break;
2315 case DASD_CQR_IN_IO:
2316 /* request in IO - terminate IO and release again */
2317 rc = device->discipline->term_IO(cqr);
2318 if (rc) {
2319 dev_err(&device->cdev->dev,
2320 "Cancelling request %p failed with rc=%d\n",
2321 cqr, rc);
2322 } else {
2323 cqr->stopclk = get_clock();
2324 }
2325 break;
2326 default: /* already finished or clear pending - do nothing */
2327 break;
2328 }
2329 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2330 dasd_schedule_device_bh(device);
2331 return rc;
2332 }
2333
2334
2335 /*
2336 * SECTION: Operations of the dasd_block layer.
2337 */
2338
2339 /*
2340 * Timeout function for dasd_block. This is used when the block layer
2341 * is waiting for something that may not come reliably, (e.g. a state
2342 * change interrupt)
2343 */
dasd_block_timeout(unsigned long ptr)2344 static void dasd_block_timeout(unsigned long ptr)
2345 {
2346 unsigned long flags;
2347 struct dasd_block *block;
2348
2349 block = (struct dasd_block *) ptr;
2350 spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
2351 /* re-activate request queue */
2352 dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING);
2353 spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
2354 dasd_schedule_block_bh(block);
2355 }
2356
2357 /*
2358 * Setup timeout for a dasd_block in jiffies.
2359 */
dasd_block_set_timer(struct dasd_block * block,int expires)2360 void dasd_block_set_timer(struct dasd_block *block, int expires)
2361 {
2362 if (expires == 0)
2363 del_timer(&block->timer);
2364 else
2365 mod_timer(&block->timer, jiffies + expires);
2366 }
2367
2368 /*
2369 * Clear timeout for a dasd_block.
2370 */
dasd_block_clear_timer(struct dasd_block * block)2371 void dasd_block_clear_timer(struct dasd_block *block)
2372 {
2373 del_timer(&block->timer);
2374 }
2375
2376 /*
2377 * Process finished error recovery ccw.
2378 */
__dasd_process_erp(struct dasd_device * device,struct dasd_ccw_req * cqr)2379 static void __dasd_process_erp(struct dasd_device *device,
2380 struct dasd_ccw_req *cqr)
2381 {
2382 dasd_erp_fn_t erp_fn;
2383
2384 if (cqr->status == DASD_CQR_DONE)
2385 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
2386 else
2387 dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
2388 erp_fn = device->discipline->erp_postaction(cqr);
2389 erp_fn(cqr);
2390 }
2391
2392 /*
2393 * Fetch requests from the block device queue.
2394 */
__dasd_process_request_queue(struct dasd_block * block)2395 static void __dasd_process_request_queue(struct dasd_block *block)
2396 {
2397 struct request_queue *queue;
2398 struct request *req;
2399 struct dasd_ccw_req *cqr;
2400 struct dasd_device *basedev;
2401 unsigned long flags;
2402 queue = block->request_queue;
2403 basedev = block->base;
2404 /* No queue ? Then there is nothing to do. */
2405 if (queue == NULL)
2406 return;
2407
2408 /*
2409 * We requeue request from the block device queue to the ccw
2410 * queue only in two states. In state DASD_STATE_READY the
2411 * partition detection is done and we need to requeue requests
2412 * for that. State DASD_STATE_ONLINE is normal block device
2413 * operation.
2414 */
2415 if (basedev->state < DASD_STATE_READY) {
2416 while ((req = blk_fetch_request(block->request_queue)))
2417 __blk_end_request_all(req, -EIO);
2418 return;
2419 }
2420 /* Now we try to fetch requests from the request queue */
2421 while ((req = blk_peek_request(queue))) {
2422 if (basedev->features & DASD_FEATURE_READONLY &&
2423 rq_data_dir(req) == WRITE) {
2424 DBF_DEV_EVENT(DBF_ERR, basedev,
2425 "Rejecting write request %p",
2426 req);
2427 blk_start_request(req);
2428 __blk_end_request_all(req, -EIO);
2429 continue;
2430 }
2431 cqr = basedev->discipline->build_cp(basedev, block, req);
2432 if (IS_ERR(cqr)) {
2433 if (PTR_ERR(cqr) == -EBUSY)
2434 break; /* normal end condition */
2435 if (PTR_ERR(cqr) == -ENOMEM)
2436 break; /* terminate request queue loop */
2437 if (PTR_ERR(cqr) == -EAGAIN) {
2438 /*
2439 * The current request cannot be build right
2440 * now, we have to try later. If this request
2441 * is the head-of-queue we stop the device
2442 * for 1/2 second.
2443 */
2444 if (!list_empty(&block->ccw_queue))
2445 break;
2446 spin_lock_irqsave(
2447 get_ccwdev_lock(basedev->cdev), flags);
2448 dasd_device_set_stop_bits(basedev,
2449 DASD_STOPPED_PENDING);
2450 spin_unlock_irqrestore(
2451 get_ccwdev_lock(basedev->cdev), flags);
2452 dasd_block_set_timer(block, HZ/2);
2453 break;
2454 }
2455 DBF_DEV_EVENT(DBF_ERR, basedev,
2456 "CCW creation failed (rc=%ld) "
2457 "on request %p",
2458 PTR_ERR(cqr), req);
2459 blk_start_request(req);
2460 __blk_end_request_all(req, -EIO);
2461 continue;
2462 }
2463 /*
2464 * Note: callback is set to dasd_return_cqr_cb in
2465 * __dasd_block_start_head to cover erp requests as well
2466 */
2467 cqr->callback_data = (void *) req;
2468 cqr->status = DASD_CQR_FILLED;
2469 blk_start_request(req);
2470 list_add_tail(&cqr->blocklist, &block->ccw_queue);
2471 dasd_profile_start(block, cqr, req);
2472 }
2473 }
2474
__dasd_cleanup_cqr(struct dasd_ccw_req * cqr)2475 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
2476 {
2477 struct request *req;
2478 int status;
2479 int error = 0;
2480
2481 req = (struct request *) cqr->callback_data;
2482 dasd_profile_end(cqr->block, cqr, req);
2483 status = cqr->block->base->discipline->free_cp(cqr, req);
2484 if (status <= 0)
2485 error = status ? status : -EIO;
2486 __blk_end_request_all(req, error);
2487 }
2488
2489 /*
2490 * Process ccw request queue.
2491 */
__dasd_process_block_ccw_queue(struct dasd_block * block,struct list_head * final_queue)2492 static void __dasd_process_block_ccw_queue(struct dasd_block *block,
2493 struct list_head *final_queue)
2494 {
2495 struct list_head *l, *n;
2496 struct dasd_ccw_req *cqr;
2497 dasd_erp_fn_t erp_fn;
2498 unsigned long flags;
2499 struct dasd_device *base = block->base;
2500
2501 restart:
2502 /* Process request with final status. */
2503 list_for_each_safe(l, n, &block->ccw_queue) {
2504 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2505 if (cqr->status != DASD_CQR_DONE &&
2506 cqr->status != DASD_CQR_FAILED &&
2507 cqr->status != DASD_CQR_NEED_ERP &&
2508 cqr->status != DASD_CQR_TERMINATED)
2509 continue;
2510
2511 if (cqr->status == DASD_CQR_TERMINATED) {
2512 base->discipline->handle_terminated_request(cqr);
2513 goto restart;
2514 }
2515
2516 /* Process requests that may be recovered */
2517 if (cqr->status == DASD_CQR_NEED_ERP) {
2518 erp_fn = base->discipline->erp_action(cqr);
2519 if (IS_ERR(erp_fn(cqr)))
2520 continue;
2521 goto restart;
2522 }
2523
2524 /* log sense for fatal error */
2525 if (cqr->status == DASD_CQR_FAILED) {
2526 dasd_log_sense(cqr, &cqr->irb);
2527 }
2528
2529 /* First of all call extended error reporting. */
2530 if (dasd_eer_enabled(base) &&
2531 cqr->status == DASD_CQR_FAILED) {
2532 dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
2533
2534 /* restart request */
2535 cqr->status = DASD_CQR_FILLED;
2536 cqr->retries = 255;
2537 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
2538 dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
2539 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
2540 flags);
2541 goto restart;
2542 }
2543
2544 /* Process finished ERP request. */
2545 if (cqr->refers) {
2546 __dasd_process_erp(base, cqr);
2547 goto restart;
2548 }
2549
2550 /* Rechain finished requests to final queue */
2551 cqr->endclk = get_clock();
2552 list_move_tail(&cqr->blocklist, final_queue);
2553 }
2554 }
2555
dasd_return_cqr_cb(struct dasd_ccw_req * cqr,void * data)2556 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
2557 {
2558 dasd_schedule_block_bh(cqr->block);
2559 }
2560
__dasd_block_start_head(struct dasd_block * block)2561 static void __dasd_block_start_head(struct dasd_block *block)
2562 {
2563 struct dasd_ccw_req *cqr;
2564
2565 if (list_empty(&block->ccw_queue))
2566 return;
2567 /* We allways begin with the first requests on the queue, as some
2568 * of previously started requests have to be enqueued on a
2569 * dasd_device again for error recovery.
2570 */
2571 list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
2572 if (cqr->status != DASD_CQR_FILLED)
2573 continue;
2574 if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) &&
2575 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2576 cqr->status = DASD_CQR_FAILED;
2577 cqr->intrc = -EPERM;
2578 dasd_schedule_block_bh(block);
2579 continue;
2580 }
2581 /* Non-temporary stop condition will trigger fail fast */
2582 if (block->base->stopped & ~DASD_STOPPED_PENDING &&
2583 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2584 (!dasd_eer_enabled(block->base))) {
2585 cqr->status = DASD_CQR_FAILED;
2586 dasd_schedule_block_bh(block);
2587 continue;
2588 }
2589 /* Don't try to start requests if device is stopped */
2590 if (block->base->stopped)
2591 return;
2592
2593 /* just a fail safe check, should not happen */
2594 if (!cqr->startdev)
2595 cqr->startdev = block->base;
2596
2597 /* make sure that the requests we submit find their way back */
2598 cqr->callback = dasd_return_cqr_cb;
2599
2600 dasd_add_request_tail(cqr);
2601 }
2602 }
2603
2604 /*
2605 * Central dasd_block layer routine. Takes requests from the generic
2606 * block layer request queue, creates ccw requests, enqueues them on
2607 * a dasd_device and processes ccw requests that have been returned.
2608 */
dasd_block_tasklet(struct dasd_block * block)2609 static void dasd_block_tasklet(struct dasd_block *block)
2610 {
2611 struct list_head final_queue;
2612 struct list_head *l, *n;
2613 struct dasd_ccw_req *cqr;
2614
2615 atomic_set(&block->tasklet_scheduled, 0);
2616 INIT_LIST_HEAD(&final_queue);
2617 spin_lock(&block->queue_lock);
2618 /* Finish off requests on ccw queue */
2619 __dasd_process_block_ccw_queue(block, &final_queue);
2620 spin_unlock(&block->queue_lock);
2621 /* Now call the callback function of requests with final status */
2622 spin_lock_irq(&block->request_queue_lock);
2623 list_for_each_safe(l, n, &final_queue) {
2624 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2625 list_del_init(&cqr->blocklist);
2626 __dasd_cleanup_cqr(cqr);
2627 }
2628 spin_lock(&block->queue_lock);
2629 /* Get new request from the block device request queue */
2630 __dasd_process_request_queue(block);
2631 /* Now check if the head of the ccw queue needs to be started. */
2632 __dasd_block_start_head(block);
2633 spin_unlock(&block->queue_lock);
2634 spin_unlock_irq(&block->request_queue_lock);
2635 dasd_put_device(block->base);
2636 }
2637
_dasd_wake_block_flush_cb(struct dasd_ccw_req * cqr,void * data)2638 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
2639 {
2640 wake_up(&dasd_flush_wq);
2641 }
2642
2643 /*
2644 * Go through all request on the dasd_block request queue, cancel them
2645 * on the respective dasd_device, and return them to the generic
2646 * block layer.
2647 */
dasd_flush_block_queue(struct dasd_block * block)2648 static int dasd_flush_block_queue(struct dasd_block *block)
2649 {
2650 struct dasd_ccw_req *cqr, *n;
2651 int rc, i;
2652 struct list_head flush_queue;
2653
2654 INIT_LIST_HEAD(&flush_queue);
2655 spin_lock_bh(&block->queue_lock);
2656 rc = 0;
2657 restart:
2658 list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
2659 /* if this request currently owned by a dasd_device cancel it */
2660 if (cqr->status >= DASD_CQR_QUEUED)
2661 rc = dasd_cancel_req(cqr);
2662 if (rc < 0)
2663 break;
2664 /* Rechain request (including erp chain) so it won't be
2665 * touched by the dasd_block_tasklet anymore.
2666 * Replace the callback so we notice when the request
2667 * is returned from the dasd_device layer.
2668 */
2669 cqr->callback = _dasd_wake_block_flush_cb;
2670 for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
2671 list_move_tail(&cqr->blocklist, &flush_queue);
2672 if (i > 1)
2673 /* moved more than one request - need to restart */
2674 goto restart;
2675 }
2676 spin_unlock_bh(&block->queue_lock);
2677 /* Now call the callback function of flushed requests */
2678 restart_cb:
2679 list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
2680 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
2681 /* Process finished ERP request. */
2682 if (cqr->refers) {
2683 spin_lock_bh(&block->queue_lock);
2684 __dasd_process_erp(block->base, cqr);
2685 spin_unlock_bh(&block->queue_lock);
2686 /* restart list_for_xx loop since dasd_process_erp
2687 * might remove multiple elements */
2688 goto restart_cb;
2689 }
2690 /* call the callback function */
2691 spin_lock_irq(&block->request_queue_lock);
2692 cqr->endclk = get_clock();
2693 list_del_init(&cqr->blocklist);
2694 __dasd_cleanup_cqr(cqr);
2695 spin_unlock_irq(&block->request_queue_lock);
2696 }
2697 return rc;
2698 }
2699
2700 /*
2701 * Schedules a call to dasd_tasklet over the device tasklet.
2702 */
dasd_schedule_block_bh(struct dasd_block * block)2703 void dasd_schedule_block_bh(struct dasd_block *block)
2704 {
2705 /* Protect against rescheduling. */
2706 if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
2707 return;
2708 /* life cycle of block is bound to it's base device */
2709 dasd_get_device(block->base);
2710 tasklet_hi_schedule(&block->tasklet);
2711 }
2712
2713
2714 /*
2715 * SECTION: external block device operations
2716 * (request queue handling, open, release, etc.)
2717 */
2718
2719 /*
2720 * Dasd request queue function. Called from ll_rw_blk.c
2721 */
do_dasd_request(struct request_queue * queue)2722 static void do_dasd_request(struct request_queue *queue)
2723 {
2724 struct dasd_block *block;
2725
2726 block = queue->queuedata;
2727 spin_lock(&block->queue_lock);
2728 /* Get new request from the block device request queue */
2729 __dasd_process_request_queue(block);
2730 /* Now check if the head of the ccw queue needs to be started. */
2731 __dasd_block_start_head(block);
2732 spin_unlock(&block->queue_lock);
2733 }
2734
2735 /*
2736 * Allocate and initialize request queue and default I/O scheduler.
2737 */
dasd_alloc_queue(struct dasd_block * block)2738 static int dasd_alloc_queue(struct dasd_block *block)
2739 {
2740 int rc;
2741
2742 block->request_queue = blk_init_queue(do_dasd_request,
2743 &block->request_queue_lock);
2744 if (block->request_queue == NULL)
2745 return -ENOMEM;
2746
2747 block->request_queue->queuedata = block;
2748
2749 elevator_exit(block->request_queue->elevator);
2750 block->request_queue->elevator = NULL;
2751 rc = elevator_init(block->request_queue, "deadline");
2752 if (rc) {
2753 blk_cleanup_queue(block->request_queue);
2754 return rc;
2755 }
2756 return 0;
2757 }
2758
2759 /*
2760 * Allocate and initialize request queue.
2761 */
dasd_setup_queue(struct dasd_block * block)2762 static void dasd_setup_queue(struct dasd_block *block)
2763 {
2764 int max;
2765
2766 if (block->base->features & DASD_FEATURE_USERAW) {
2767 /*
2768 * the max_blocks value for raw_track access is 256
2769 * it is higher than the native ECKD value because we
2770 * only need one ccw per track
2771 * so the max_hw_sectors are
2772 * 2048 x 512B = 1024kB = 16 tracks
2773 */
2774 max = 2048;
2775 } else {
2776 max = block->base->discipline->max_blocks << block->s2b_shift;
2777 }
2778 blk_queue_logical_block_size(block->request_queue,
2779 block->bp_block);
2780 blk_queue_max_hw_sectors(block->request_queue, max);
2781 blk_queue_max_segments(block->request_queue, -1L);
2782 /* with page sized segments we can translate each segement into
2783 * one idaw/tidaw
2784 */
2785 blk_queue_max_segment_size(block->request_queue, PAGE_SIZE);
2786 blk_queue_segment_boundary(block->request_queue, PAGE_SIZE - 1);
2787 }
2788
2789 /*
2790 * Deactivate and free request queue.
2791 */
dasd_free_queue(struct dasd_block * block)2792 static void dasd_free_queue(struct dasd_block *block)
2793 {
2794 if (block->request_queue) {
2795 blk_cleanup_queue(block->request_queue);
2796 block->request_queue = NULL;
2797 }
2798 }
2799
2800 /*
2801 * Flush request on the request queue.
2802 */
dasd_flush_request_queue(struct dasd_block * block)2803 static void dasd_flush_request_queue(struct dasd_block *block)
2804 {
2805 struct request *req;
2806
2807 if (!block->request_queue)
2808 return;
2809
2810 spin_lock_irq(&block->request_queue_lock);
2811 while ((req = blk_fetch_request(block->request_queue)))
2812 __blk_end_request_all(req, -EIO);
2813 spin_unlock_irq(&block->request_queue_lock);
2814 }
2815
dasd_open(struct block_device * bdev,fmode_t mode)2816 static int dasd_open(struct block_device *bdev, fmode_t mode)
2817 {
2818 struct dasd_device *base;
2819 int rc;
2820
2821 base = dasd_device_from_gendisk(bdev->bd_disk);
2822 if (!base)
2823 return -ENODEV;
2824
2825 atomic_inc(&base->block->open_count);
2826 if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
2827 rc = -ENODEV;
2828 goto unlock;
2829 }
2830
2831 if (!try_module_get(base->discipline->owner)) {
2832 rc = -EINVAL;
2833 goto unlock;
2834 }
2835
2836 if (dasd_probeonly) {
2837 dev_info(&base->cdev->dev,
2838 "Accessing the DASD failed because it is in "
2839 "probeonly mode\n");
2840 rc = -EPERM;
2841 goto out;
2842 }
2843
2844 if (base->state <= DASD_STATE_BASIC) {
2845 DBF_DEV_EVENT(DBF_ERR, base, " %s",
2846 " Cannot open unrecognized device");
2847 rc = -ENODEV;
2848 goto out;
2849 }
2850
2851 if ((mode & FMODE_WRITE) &&
2852 (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) ||
2853 (base->features & DASD_FEATURE_READONLY))) {
2854 rc = -EROFS;
2855 goto out;
2856 }
2857
2858 dasd_put_device(base);
2859 return 0;
2860
2861 out:
2862 module_put(base->discipline->owner);
2863 unlock:
2864 atomic_dec(&base->block->open_count);
2865 dasd_put_device(base);
2866 return rc;
2867 }
2868
dasd_release(struct gendisk * disk,fmode_t mode)2869 static int dasd_release(struct gendisk *disk, fmode_t mode)
2870 {
2871 struct dasd_device *base;
2872
2873 base = dasd_device_from_gendisk(disk);
2874 if (!base)
2875 return -ENODEV;
2876
2877 atomic_dec(&base->block->open_count);
2878 module_put(base->discipline->owner);
2879 dasd_put_device(base);
2880 return 0;
2881 }
2882
2883 /*
2884 * Return disk geometry.
2885 */
dasd_getgeo(struct block_device * bdev,struct hd_geometry * geo)2886 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
2887 {
2888 struct dasd_device *base;
2889
2890 base = dasd_device_from_gendisk(bdev->bd_disk);
2891 if (!base)
2892 return -ENODEV;
2893
2894 if (!base->discipline ||
2895 !base->discipline->fill_geometry) {
2896 dasd_put_device(base);
2897 return -EINVAL;
2898 }
2899 base->discipline->fill_geometry(base->block, geo);
2900 geo->start = get_start_sect(bdev) >> base->block->s2b_shift;
2901 dasd_put_device(base);
2902 return 0;
2903 }
2904
2905 const struct block_device_operations
2906 dasd_device_operations = {
2907 .owner = THIS_MODULE,
2908 .open = dasd_open,
2909 .release = dasd_release,
2910 .ioctl = dasd_ioctl,
2911 .compat_ioctl = dasd_ioctl,
2912 .getgeo = dasd_getgeo,
2913 };
2914
2915 /*******************************************************************************
2916 * end of block device operations
2917 */
2918
2919 static void
dasd_exit(void)2920 dasd_exit(void)
2921 {
2922 #ifdef CONFIG_PROC_FS
2923 dasd_proc_exit();
2924 #endif
2925 dasd_eer_exit();
2926 if (dasd_page_cache != NULL) {
2927 kmem_cache_destroy(dasd_page_cache);
2928 dasd_page_cache = NULL;
2929 }
2930 dasd_gendisk_exit();
2931 dasd_devmap_exit();
2932 if (dasd_debug_area != NULL) {
2933 debug_unregister(dasd_debug_area);
2934 dasd_debug_area = NULL;
2935 }
2936 dasd_statistics_removeroot();
2937 }
2938
2939 /*
2940 * SECTION: common functions for ccw_driver use
2941 */
2942
2943 /*
2944 * Is the device read-only?
2945 * Note that this function does not report the setting of the
2946 * readonly device attribute, but how it is configured in z/VM.
2947 */
dasd_device_is_ro(struct dasd_device * device)2948 int dasd_device_is_ro(struct dasd_device *device)
2949 {
2950 struct ccw_dev_id dev_id;
2951 struct diag210 diag_data;
2952 int rc;
2953
2954 if (!MACHINE_IS_VM)
2955 return 0;
2956 ccw_device_get_id(device->cdev, &dev_id);
2957 memset(&diag_data, 0, sizeof(diag_data));
2958 diag_data.vrdcdvno = dev_id.devno;
2959 diag_data.vrdclen = sizeof(diag_data);
2960 rc = diag210(&diag_data);
2961 if (rc == 0 || rc == 2) {
2962 return diag_data.vrdcvfla & 0x80;
2963 } else {
2964 DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d",
2965 dev_id.devno, rc);
2966 return 0;
2967 }
2968 }
2969 EXPORT_SYMBOL_GPL(dasd_device_is_ro);
2970
dasd_generic_auto_online(void * data,async_cookie_t cookie)2971 static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
2972 {
2973 struct ccw_device *cdev = data;
2974 int ret;
2975
2976 ret = ccw_device_set_online(cdev);
2977 if (ret)
2978 pr_warning("%s: Setting the DASD online failed with rc=%d\n",
2979 dev_name(&cdev->dev), ret);
2980 }
2981
2982 /*
2983 * Initial attempt at a probe function. this can be simplified once
2984 * the other detection code is gone.
2985 */
dasd_generic_probe(struct ccw_device * cdev,struct dasd_discipline * discipline)2986 int dasd_generic_probe(struct ccw_device *cdev,
2987 struct dasd_discipline *discipline)
2988 {
2989 int ret;
2990
2991 ret = dasd_add_sysfs_files(cdev);
2992 if (ret) {
2993 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s",
2994 "dasd_generic_probe: could not add "
2995 "sysfs entries");
2996 return ret;
2997 }
2998 cdev->handler = &dasd_int_handler;
2999
3000 /*
3001 * Automatically online either all dasd devices (dasd_autodetect)
3002 * or all devices specified with dasd= parameters during
3003 * initial probe.
3004 */
3005 if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
3006 (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
3007 async_schedule(dasd_generic_auto_online, cdev);
3008 return 0;
3009 }
3010
3011 /*
3012 * This will one day be called from a global not_oper handler.
3013 * It is also used by driver_unregister during module unload.
3014 */
dasd_generic_remove(struct ccw_device * cdev)3015 void dasd_generic_remove(struct ccw_device *cdev)
3016 {
3017 struct dasd_device *device;
3018 struct dasd_block *block;
3019
3020 cdev->handler = NULL;
3021
3022 dasd_remove_sysfs_files(cdev);
3023 device = dasd_device_from_cdev(cdev);
3024 if (IS_ERR(device))
3025 return;
3026 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3027 /* Already doing offline processing */
3028 dasd_put_device(device);
3029 return;
3030 }
3031 /*
3032 * This device is removed unconditionally. Set offline
3033 * flag to prevent dasd_open from opening it while it is
3034 * no quite down yet.
3035 */
3036 dasd_set_target_state(device, DASD_STATE_NEW);
3037 /* dasd_delete_device destroys the device reference. */
3038 block = device->block;
3039 dasd_delete_device(device);
3040 /*
3041 * life cycle of block is bound to device, so delete it after
3042 * device was safely removed
3043 */
3044 if (block)
3045 dasd_free_block(block);
3046 }
3047
3048 /*
3049 * Activate a device. This is called from dasd_{eckd,fba}_probe() when either
3050 * the device is detected for the first time and is supposed to be used
3051 * or the user has started activation through sysfs.
3052 */
dasd_generic_set_online(struct ccw_device * cdev,struct dasd_discipline * base_discipline)3053 int dasd_generic_set_online(struct ccw_device *cdev,
3054 struct dasd_discipline *base_discipline)
3055 {
3056 struct dasd_discipline *discipline;
3057 struct dasd_device *device;
3058 int rc;
3059
3060 /* first online clears initial online feature flag */
3061 dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
3062 device = dasd_create_device(cdev);
3063 if (IS_ERR(device))
3064 return PTR_ERR(device);
3065
3066 discipline = base_discipline;
3067 if (device->features & DASD_FEATURE_USEDIAG) {
3068 if (!dasd_diag_discipline_pointer) {
3069 pr_warning("%s Setting the DASD online failed because "
3070 "of missing DIAG discipline\n",
3071 dev_name(&cdev->dev));
3072 dasd_delete_device(device);
3073 return -ENODEV;
3074 }
3075 discipline = dasd_diag_discipline_pointer;
3076 }
3077 if (!try_module_get(base_discipline->owner)) {
3078 dasd_delete_device(device);
3079 return -EINVAL;
3080 }
3081 if (!try_module_get(discipline->owner)) {
3082 module_put(base_discipline->owner);
3083 dasd_delete_device(device);
3084 return -EINVAL;
3085 }
3086 device->base_discipline = base_discipline;
3087 device->discipline = discipline;
3088
3089 /* check_device will allocate block device if necessary */
3090 rc = discipline->check_device(device);
3091 if (rc) {
3092 pr_warning("%s Setting the DASD online with discipline %s "
3093 "failed with rc=%i\n",
3094 dev_name(&cdev->dev), discipline->name, rc);
3095 module_put(discipline->owner);
3096 module_put(base_discipline->owner);
3097 dasd_delete_device(device);
3098 return rc;
3099 }
3100
3101 dasd_set_target_state(device, DASD_STATE_ONLINE);
3102 if (device->state <= DASD_STATE_KNOWN) {
3103 pr_warning("%s Setting the DASD online failed because of a "
3104 "missing discipline\n", dev_name(&cdev->dev));
3105 rc = -ENODEV;
3106 dasd_set_target_state(device, DASD_STATE_NEW);
3107 if (device->block)
3108 dasd_free_block(device->block);
3109 dasd_delete_device(device);
3110 } else
3111 pr_debug("dasd_generic device %s found\n",
3112 dev_name(&cdev->dev));
3113
3114 wait_event(dasd_init_waitq, _wait_for_device(device));
3115
3116 dasd_put_device(device);
3117 return rc;
3118 }
3119
dasd_generic_set_offline(struct ccw_device * cdev)3120 int dasd_generic_set_offline(struct ccw_device *cdev)
3121 {
3122 struct dasd_device *device;
3123 struct dasd_block *block;
3124 int max_count, open_count;
3125
3126 device = dasd_device_from_cdev(cdev);
3127 if (IS_ERR(device))
3128 return PTR_ERR(device);
3129 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3130 /* Already doing offline processing */
3131 dasd_put_device(device);
3132 return 0;
3133 }
3134 /*
3135 * We must make sure that this device is currently not in use.
3136 * The open_count is increased for every opener, that includes
3137 * the blkdev_get in dasd_scan_partitions. We are only interested
3138 * in the other openers.
3139 */
3140 if (device->block) {
3141 max_count = device->block->bdev ? 0 : -1;
3142 open_count = atomic_read(&device->block->open_count);
3143 if (open_count > max_count) {
3144 if (open_count > 0)
3145 pr_warning("%s: The DASD cannot be set offline "
3146 "with open count %i\n",
3147 dev_name(&cdev->dev), open_count);
3148 else
3149 pr_warning("%s: The DASD cannot be set offline "
3150 "while it is in use\n",
3151 dev_name(&cdev->dev));
3152 clear_bit(DASD_FLAG_OFFLINE, &device->flags);
3153 dasd_put_device(device);
3154 return -EBUSY;
3155 }
3156 }
3157 dasd_set_target_state(device, DASD_STATE_NEW);
3158 /* dasd_delete_device destroys the device reference. */
3159 block = device->block;
3160 dasd_delete_device(device);
3161 /*
3162 * life cycle of block is bound to device, so delete it after
3163 * device was safely removed
3164 */
3165 if (block)
3166 dasd_free_block(block);
3167 return 0;
3168 }
3169
dasd_generic_last_path_gone(struct dasd_device * device)3170 int dasd_generic_last_path_gone(struct dasd_device *device)
3171 {
3172 struct dasd_ccw_req *cqr;
3173
3174 dev_warn(&device->cdev->dev, "No operational channel path is left "
3175 "for the device\n");
3176 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone");
3177 /* First of all call extended error reporting. */
3178 dasd_eer_write(device, NULL, DASD_EER_NOPATH);
3179
3180 if (device->state < DASD_STATE_BASIC)
3181 return 0;
3182 /* Device is active. We want to keep it. */
3183 list_for_each_entry(cqr, &device->ccw_queue, devlist)
3184 if ((cqr->status == DASD_CQR_IN_IO) ||
3185 (cqr->status == DASD_CQR_CLEAR_PENDING)) {
3186 cqr->status = DASD_CQR_QUEUED;
3187 cqr->retries++;
3188 }
3189 dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT);
3190 dasd_device_clear_timer(device);
3191 dasd_schedule_device_bh(device);
3192 return 1;
3193 }
3194 EXPORT_SYMBOL_GPL(dasd_generic_last_path_gone);
3195
dasd_generic_path_operational(struct dasd_device * device)3196 int dasd_generic_path_operational(struct dasd_device *device)
3197 {
3198 dev_info(&device->cdev->dev, "A channel path to the device has become "
3199 "operational\n");
3200 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational");
3201 dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT);
3202 if (device->stopped & DASD_UNRESUMED_PM) {
3203 dasd_device_remove_stop_bits(device, DASD_UNRESUMED_PM);
3204 dasd_restore_device(device);
3205 return 1;
3206 }
3207 dasd_schedule_device_bh(device);
3208 if (device->block)
3209 dasd_schedule_block_bh(device->block);
3210 return 1;
3211 }
3212 EXPORT_SYMBOL_GPL(dasd_generic_path_operational);
3213
dasd_generic_notify(struct ccw_device * cdev,int event)3214 int dasd_generic_notify(struct ccw_device *cdev, int event)
3215 {
3216 struct dasd_device *device;
3217 int ret;
3218
3219 device = dasd_device_from_cdev_locked(cdev);
3220 if (IS_ERR(device))
3221 return 0;
3222 ret = 0;
3223 switch (event) {
3224 case CIO_GONE:
3225 case CIO_BOXED:
3226 case CIO_NO_PATH:
3227 device->path_data.opm = 0;
3228 device->path_data.ppm = 0;
3229 device->path_data.npm = 0;
3230 ret = dasd_generic_last_path_gone(device);
3231 break;
3232 case CIO_OPER:
3233 ret = 1;
3234 if (device->path_data.opm)
3235 ret = dasd_generic_path_operational(device);
3236 break;
3237 }
3238 dasd_put_device(device);
3239 return ret;
3240 }
3241
dasd_generic_path_event(struct ccw_device * cdev,int * path_event)3242 void dasd_generic_path_event(struct ccw_device *cdev, int *path_event)
3243 {
3244 int chp;
3245 __u8 oldopm, eventlpm;
3246 struct dasd_device *device;
3247
3248 device = dasd_device_from_cdev_locked(cdev);
3249 if (IS_ERR(device))
3250 return;
3251 for (chp = 0; chp < 8; chp++) {
3252 eventlpm = 0x80 >> chp;
3253 if (path_event[chp] & PE_PATH_GONE) {
3254 oldopm = device->path_data.opm;
3255 device->path_data.opm &= ~eventlpm;
3256 device->path_data.ppm &= ~eventlpm;
3257 device->path_data.npm &= ~eventlpm;
3258 if (oldopm && !device->path_data.opm)
3259 dasd_generic_last_path_gone(device);
3260 }
3261 if (path_event[chp] & PE_PATH_AVAILABLE) {
3262 device->path_data.opm &= ~eventlpm;
3263 device->path_data.ppm &= ~eventlpm;
3264 device->path_data.npm &= ~eventlpm;
3265 device->path_data.tbvpm |= eventlpm;
3266 dasd_schedule_device_bh(device);
3267 }
3268 if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) {
3269 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
3270 "Pathgroup re-established\n");
3271 if (device->discipline->kick_validate)
3272 device->discipline->kick_validate(device);
3273 }
3274 }
3275 dasd_put_device(device);
3276 }
3277 EXPORT_SYMBOL_GPL(dasd_generic_path_event);
3278
dasd_generic_verify_path(struct dasd_device * device,__u8 lpm)3279 int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm)
3280 {
3281 if (!device->path_data.opm && lpm) {
3282 device->path_data.opm = lpm;
3283 dasd_generic_path_operational(device);
3284 } else
3285 device->path_data.opm |= lpm;
3286 return 0;
3287 }
3288 EXPORT_SYMBOL_GPL(dasd_generic_verify_path);
3289
3290
dasd_generic_pm_freeze(struct ccw_device * cdev)3291 int dasd_generic_pm_freeze(struct ccw_device *cdev)
3292 {
3293 struct dasd_ccw_req *cqr, *n;
3294 int rc;
3295 struct list_head freeze_queue;
3296 struct dasd_device *device = dasd_device_from_cdev(cdev);
3297
3298 if (IS_ERR(device))
3299 return PTR_ERR(device);
3300
3301 /* mark device as suspended */
3302 set_bit(DASD_FLAG_SUSPENDED, &device->flags);
3303
3304 if (device->discipline->freeze)
3305 rc = device->discipline->freeze(device);
3306
3307 /* disallow new I/O */
3308 dasd_device_set_stop_bits(device, DASD_STOPPED_PM);
3309 /* clear active requests */
3310 INIT_LIST_HEAD(&freeze_queue);
3311 spin_lock_irq(get_ccwdev_lock(cdev));
3312 rc = 0;
3313 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
3314 /* Check status and move request to flush_queue */
3315 if (cqr->status == DASD_CQR_IN_IO) {
3316 rc = device->discipline->term_IO(cqr);
3317 if (rc) {
3318 /* unable to terminate requeust */
3319 dev_err(&device->cdev->dev,
3320 "Unable to terminate request %p "
3321 "on suspend\n", cqr);
3322 spin_unlock_irq(get_ccwdev_lock(cdev));
3323 dasd_put_device(device);
3324 return rc;
3325 }
3326 }
3327 list_move_tail(&cqr->devlist, &freeze_queue);
3328 }
3329
3330 spin_unlock_irq(get_ccwdev_lock(cdev));
3331
3332 list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) {
3333 wait_event(dasd_flush_wq,
3334 (cqr->status != DASD_CQR_CLEAR_PENDING));
3335 if (cqr->status == DASD_CQR_CLEARED)
3336 cqr->status = DASD_CQR_QUEUED;
3337 }
3338 /* move freeze_queue to start of the ccw_queue */
3339 spin_lock_irq(get_ccwdev_lock(cdev));
3340 list_splice_tail(&freeze_queue, &device->ccw_queue);
3341 spin_unlock_irq(get_ccwdev_lock(cdev));
3342
3343 dasd_put_device(device);
3344 return rc;
3345 }
3346 EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze);
3347
dasd_generic_restore_device(struct ccw_device * cdev)3348 int dasd_generic_restore_device(struct ccw_device *cdev)
3349 {
3350 struct dasd_device *device = dasd_device_from_cdev(cdev);
3351 int rc = 0;
3352
3353 if (IS_ERR(device))
3354 return PTR_ERR(device);
3355
3356 /* allow new IO again */
3357 dasd_device_remove_stop_bits(device,
3358 (DASD_STOPPED_PM | DASD_UNRESUMED_PM));
3359
3360 dasd_schedule_device_bh(device);
3361
3362 /*
3363 * call discipline restore function
3364 * if device is stopped do nothing e.g. for disconnected devices
3365 */
3366 if (device->discipline->restore && !(device->stopped))
3367 rc = device->discipline->restore(device);
3368 if (rc || device->stopped)
3369 /*
3370 * if the resume failed for the DASD we put it in
3371 * an UNRESUMED stop state
3372 */
3373 device->stopped |= DASD_UNRESUMED_PM;
3374
3375 if (device->block)
3376 dasd_schedule_block_bh(device->block);
3377
3378 clear_bit(DASD_FLAG_SUSPENDED, &device->flags);
3379 dasd_put_device(device);
3380 return 0;
3381 }
3382 EXPORT_SYMBOL_GPL(dasd_generic_restore_device);
3383
dasd_generic_build_rdc(struct dasd_device * device,void * rdc_buffer,int rdc_buffer_size,int magic)3384 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
3385 void *rdc_buffer,
3386 int rdc_buffer_size,
3387 int magic)
3388 {
3389 struct dasd_ccw_req *cqr;
3390 struct ccw1 *ccw;
3391 unsigned long *idaw;
3392
3393 cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device);
3394
3395 if (IS_ERR(cqr)) {
3396 /* internal error 13 - Allocating the RDC request failed*/
3397 dev_err(&device->cdev->dev,
3398 "An error occurred in the DASD device driver, "
3399 "reason=%s\n", "13");
3400 return cqr;
3401 }
3402
3403 ccw = cqr->cpaddr;
3404 ccw->cmd_code = CCW_CMD_RDC;
3405 if (idal_is_needed(rdc_buffer, rdc_buffer_size)) {
3406 idaw = (unsigned long *) (cqr->data);
3407 ccw->cda = (__u32)(addr_t) idaw;
3408 ccw->flags = CCW_FLAG_IDA;
3409 idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size);
3410 } else {
3411 ccw->cda = (__u32)(addr_t) rdc_buffer;
3412 ccw->flags = 0;
3413 }
3414
3415 ccw->count = rdc_buffer_size;
3416 cqr->startdev = device;
3417 cqr->memdev = device;
3418 cqr->expires = 10*HZ;
3419 cqr->retries = 256;
3420 cqr->buildclk = get_clock();
3421 cqr->status = DASD_CQR_FILLED;
3422 return cqr;
3423 }
3424
3425
dasd_generic_read_dev_chars(struct dasd_device * device,int magic,void * rdc_buffer,int rdc_buffer_size)3426 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
3427 void *rdc_buffer, int rdc_buffer_size)
3428 {
3429 int ret;
3430 struct dasd_ccw_req *cqr;
3431
3432 cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size,
3433 magic);
3434 if (IS_ERR(cqr))
3435 return PTR_ERR(cqr);
3436
3437 ret = dasd_sleep_on(cqr);
3438 dasd_sfree_request(cqr, cqr->memdev);
3439 return ret;
3440 }
3441 EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
3442
3443 /*
3444 * In command mode and transport mode we need to look for sense
3445 * data in different places. The sense data itself is allways
3446 * an array of 32 bytes, so we can unify the sense data access
3447 * for both modes.
3448 */
dasd_get_sense(struct irb * irb)3449 char *dasd_get_sense(struct irb *irb)
3450 {
3451 struct tsb *tsb = NULL;
3452 char *sense = NULL;
3453
3454 if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
3455 if (irb->scsw.tm.tcw)
3456 tsb = tcw_get_tsb((struct tcw *)(unsigned long)
3457 irb->scsw.tm.tcw);
3458 if (tsb && tsb->length == 64 && tsb->flags)
3459 switch (tsb->flags & 0x07) {
3460 case 1: /* tsa_iostat */
3461 sense = tsb->tsa.iostat.sense;
3462 break;
3463 case 2: /* tsa_ddpc */
3464 sense = tsb->tsa.ddpc.sense;
3465 break;
3466 default:
3467 /* currently we don't use interrogate data */
3468 break;
3469 }
3470 } else if (irb->esw.esw0.erw.cons) {
3471 sense = irb->ecw;
3472 }
3473 return sense;
3474 }
3475 EXPORT_SYMBOL_GPL(dasd_get_sense);
3476
dasd_init(void)3477 static int __init dasd_init(void)
3478 {
3479 int rc;
3480
3481 init_waitqueue_head(&dasd_init_waitq);
3482 init_waitqueue_head(&dasd_flush_wq);
3483 init_waitqueue_head(&generic_waitq);
3484
3485 /* register 'common' DASD debug area, used for all DBF_XXX calls */
3486 dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
3487 if (dasd_debug_area == NULL) {
3488 rc = -ENOMEM;
3489 goto failed;
3490 }
3491 debug_register_view(dasd_debug_area, &debug_sprintf_view);
3492 debug_set_level(dasd_debug_area, DBF_WARNING);
3493
3494 DBF_EVENT(DBF_EMERG, "%s", "debug area created");
3495
3496 dasd_diag_discipline_pointer = NULL;
3497
3498 dasd_statistics_createroot();
3499
3500 rc = dasd_devmap_init();
3501 if (rc)
3502 goto failed;
3503 rc = dasd_gendisk_init();
3504 if (rc)
3505 goto failed;
3506 rc = dasd_parse();
3507 if (rc)
3508 goto failed;
3509 rc = dasd_eer_init();
3510 if (rc)
3511 goto failed;
3512 #ifdef CONFIG_PROC_FS
3513 rc = dasd_proc_init();
3514 if (rc)
3515 goto failed;
3516 #endif
3517
3518 return 0;
3519 failed:
3520 pr_info("The DASD device driver could not be initialized\n");
3521 dasd_exit();
3522 return rc;
3523 }
3524
3525 module_init(dasd_init);
3526 module_exit(dasd_exit);
3527
3528 EXPORT_SYMBOL(dasd_debug_area);
3529 EXPORT_SYMBOL(dasd_diag_discipline_pointer);
3530
3531 EXPORT_SYMBOL(dasd_add_request_head);
3532 EXPORT_SYMBOL(dasd_add_request_tail);
3533 EXPORT_SYMBOL(dasd_cancel_req);
3534 EXPORT_SYMBOL(dasd_device_clear_timer);
3535 EXPORT_SYMBOL(dasd_block_clear_timer);
3536 EXPORT_SYMBOL(dasd_enable_device);
3537 EXPORT_SYMBOL(dasd_int_handler);
3538 EXPORT_SYMBOL(dasd_kfree_request);
3539 EXPORT_SYMBOL(dasd_kick_device);
3540 EXPORT_SYMBOL(dasd_kmalloc_request);
3541 EXPORT_SYMBOL(dasd_schedule_device_bh);
3542 EXPORT_SYMBOL(dasd_schedule_block_bh);
3543 EXPORT_SYMBOL(dasd_set_target_state);
3544 EXPORT_SYMBOL(dasd_device_set_timer);
3545 EXPORT_SYMBOL(dasd_block_set_timer);
3546 EXPORT_SYMBOL(dasd_sfree_request);
3547 EXPORT_SYMBOL(dasd_sleep_on);
3548 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
3549 EXPORT_SYMBOL(dasd_sleep_on_interruptible);
3550 EXPORT_SYMBOL(dasd_smalloc_request);
3551 EXPORT_SYMBOL(dasd_start_IO);
3552 EXPORT_SYMBOL(dasd_term_IO);
3553
3554 EXPORT_SYMBOL_GPL(dasd_generic_probe);
3555 EXPORT_SYMBOL_GPL(dasd_generic_remove);
3556 EXPORT_SYMBOL_GPL(dasd_generic_notify);
3557 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
3558 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
3559 EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
3560 EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
3561 EXPORT_SYMBOL_GPL(dasd_alloc_block);
3562 EXPORT_SYMBOL_GPL(dasd_free_block);
3563