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