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[S390] Remove error checking from copy_oldmem_page()
[linux/fpc-iii.git] / drivers / s390 / block / dasd.c
blob65894f05a801d073974ae11a6599b59c45e5daee
1 /*
2 * File...........: linux/drivers/s390/block/dasd.c
3 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4 * Horst Hummel <Horst.Hummel@de.ibm.com>
5 * Carsten Otte <Cotte@de.ibm.com>
6 * Martin Schwidefsky <schwidefsky@de.ibm.com>
7 * Bugreports.to..: <Linux390@de.ibm.com>
8 * Copyright IBM Corp. 1999, 2009
9 */
10
11 #define KMSG_COMPONENT "dasd"
12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14 #include <linux/kmod.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/ctype.h>
18 #include <linux/major.h>
19 #include <linux/slab.h>
20 #include <linux/buffer_head.h>
21 #include <linux/hdreg.h>
22 #include <linux/async.h>
23 #include <linux/mutex.h>
24 #include <linux/debugfs.h>
25 #include <linux/seq_file.h>
26 #include <linux/vmalloc.h>
27
28 #include <asm/ccwdev.h>
29 #include <asm/ebcdic.h>
30 #include <asm/idals.h>
31 #include <asm/itcw.h>
32 #include <asm/diag.h>
33
34 /* This is ugly... */
35 #define PRINTK_HEADER "dasd:"
36
37 #include "dasd_int.h"
38 /*
39 * SECTION: Constant definitions to be used within this file
40 */
41 #define DASD_CHANQ_MAX_SIZE 4
42
43 #define DASD_SLEEPON_START_TAG (void *) 1
44 #define DASD_SLEEPON_END_TAG (void *) 2
45
46 /*
47 * SECTION: exported variables of dasd.c
48 */
49 debug_info_t *dasd_debug_area;
50 static struct dentry *dasd_debugfs_root_entry;
51 struct dasd_discipline *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 2000 IBM Corporation");
57 MODULE_SUPPORTED_DEVICE("dasd");
58 MODULE_LICENSE("GPL");
59
60 /*
61 * SECTION: prototypes for static functions of dasd.c
62 */
63 static int dasd_alloc_queue(struct dasd_block *);
64 static void dasd_setup_queue(struct dasd_block *);
65 static void dasd_free_queue(struct dasd_block *);
66 static void dasd_flush_request_queue(struct dasd_block *);
67 static int dasd_flush_block_queue(struct dasd_block *);
68 static void dasd_device_tasklet(struct dasd_device *);
69 static void dasd_block_tasklet(struct dasd_block *);
70 static void do_kick_device(struct work_struct *);
71 static void do_restore_device(struct work_struct *);
72 static void do_reload_device(struct work_struct *);
73 static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
74 static void dasd_device_timeout(unsigned long);
75 static void dasd_block_timeout(unsigned long);
76 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
77 static void dasd_profile_init(struct dasd_profile *, struct dentry *);
78 static void dasd_profile_exit(struct dasd_profile *);
79
80 /*
81 * SECTION: Operations on the device structure.
82 */
83 static wait_queue_head_t dasd_init_waitq;
84 static wait_queue_head_t dasd_flush_wq;
85 static wait_queue_head_t generic_waitq;
86
87 /*
88 * Allocate memory for a new device structure.
89 */
90 struct dasd_device *dasd_alloc_device(void)
91 {
92 struct dasd_device *device;
93
94 device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
95 if (!device)
96 return ERR_PTR(-ENOMEM);
97
98 /* Get two pages for normal block device operations. */
99 device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
100 if (!device->ccw_mem) {
101 kfree(device);
102 return ERR_PTR(-ENOMEM);
103 }
104 /* Get one page for error recovery. */
105 device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
106 if (!device->erp_mem) {
107 free_pages((unsigned long) device->ccw_mem, 1);
108 kfree(device);
109 return ERR_PTR(-ENOMEM);
110 }
111
112 dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
113 dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
114 spin_lock_init(&device->mem_lock);
115 atomic_set(&device->tasklet_scheduled, 0);
116 tasklet_init(&device->tasklet,
117 (void (*)(unsigned long)) dasd_device_tasklet,
118 (unsigned long) device);
119 INIT_LIST_HEAD(&device->ccw_queue);
120 init_timer(&device->timer);
121 device->timer.function = dasd_device_timeout;
122 device->timer.data = (unsigned long) device;
123 INIT_WORK(&device->kick_work, do_kick_device);
124 INIT_WORK(&device->restore_device, do_restore_device);
125 INIT_WORK(&device->reload_device, do_reload_device);
126 device->state = DASD_STATE_NEW;
127 device->target = DASD_STATE_NEW;
128 mutex_init(&device->state_mutex);
129 spin_lock_init(&device->profile.lock);
130 return device;
131 }
132
133 /*
134 * Free memory of a device structure.
135 */
136 void dasd_free_device(struct dasd_device *device)
137 {
138 kfree(device->private);
139 free_page((unsigned long) device->erp_mem);
140 free_pages((unsigned long) device->ccw_mem, 1);
141 kfree(device);
142 }
143
144 /*
145 * Allocate memory for a new device structure.
146 */
147 struct dasd_block *dasd_alloc_block(void)
148 {
149 struct dasd_block *block;
150
151 block = kzalloc(sizeof(*block), GFP_ATOMIC);
152 if (!block)
153 return ERR_PTR(-ENOMEM);
154 /* open_count = 0 means device online but not in use */
155 atomic_set(&block->open_count, -1);
156
157 spin_lock_init(&block->request_queue_lock);
158 atomic_set(&block->tasklet_scheduled, 0);
159 tasklet_init(&block->tasklet,
160 (void (*)(unsigned long)) dasd_block_tasklet,
161 (unsigned long) block);
162 INIT_LIST_HEAD(&block->ccw_queue);
163 spin_lock_init(&block->queue_lock);
164 init_timer(&block->timer);
165 block->timer.function = dasd_block_timeout;
166 block->timer.data = (unsigned long) block;
167 spin_lock_init(&block->profile.lock);
168
169 return block;
170 }
171
172 /*
173 * Free memory of a device structure.
174 */
175 void dasd_free_block(struct dasd_block *block)
176 {
177 kfree(block);
178 }
179
180 /*
181 * Make a new device known to the system.
182 */
183 static int dasd_state_new_to_known(struct dasd_device *device)
184 {
185 int rc;
186
187 /*
188 * As long as the device is not in state DASD_STATE_NEW we want to
189 * keep the reference count > 0.
190 */
191 dasd_get_device(device);
192
193 if (device->block) {
194 rc = dasd_alloc_queue(device->block);
195 if (rc) {
196 dasd_put_device(device);
197 return rc;
198 }
199 }
200 device->state = DASD_STATE_KNOWN;
201 return 0;
202 }
203
204 /*
205 * Let the system forget about a device.
206 */
207 static int dasd_state_known_to_new(struct dasd_device *device)
208 {
209 /* Disable extended error reporting for this device. */
210 dasd_eer_disable(device);
211 /* Forget the discipline information. */
212 if (device->discipline) {
213 if (device->discipline->uncheck_device)
214 device->discipline->uncheck_device(device);
215 module_put(device->discipline->owner);
216 }
217 device->discipline = NULL;
218 if (device->base_discipline)
219 module_put(device->base_discipline->owner);
220 device->base_discipline = NULL;
221 device->state = DASD_STATE_NEW;
222
223 if (device->block)
224 dasd_free_queue(device->block);
225
226 /* Give up reference we took in dasd_state_new_to_known. */
227 dasd_put_device(device);
228 return 0;
229 }
230
231 static struct dentry *dasd_debugfs_setup(const char *name,
232 struct dentry *base_dentry)
233 {
234 struct dentry *pde;
235
236 if (!base_dentry)
237 return NULL;
238 pde = debugfs_create_dir(name, base_dentry);
239 if (!pde || IS_ERR(pde))
240 return NULL;
241 return pde;
242 }
243
244 /*
245 * Request the irq line for the device.
246 */
247 static int dasd_state_known_to_basic(struct dasd_device *device)
248 {
249 struct dasd_block *block = device->block;
250 int rc;
251
252 /* Allocate and register gendisk structure. */
253 if (block) {
254 rc = dasd_gendisk_alloc(block);
255 if (rc)
256 return rc;
257 block->debugfs_dentry =
258 dasd_debugfs_setup(block->gdp->disk_name,
259 dasd_debugfs_root_entry);
260 dasd_profile_init(&block->profile, block->debugfs_dentry);
261 if (dasd_global_profile_level == DASD_PROFILE_ON)
262 dasd_profile_on(&device->block->profile);
263 }
264 device->debugfs_dentry =
265 dasd_debugfs_setup(dev_name(&device->cdev->dev),
266 dasd_debugfs_root_entry);
267 dasd_profile_init(&device->profile, device->debugfs_dentry);
268
269 /* register 'device' debug area, used for all DBF_DEV_XXX calls */
270 device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
271 8 * sizeof(long));
272 debug_register_view(device->debug_area, &debug_sprintf_view);
273 debug_set_level(device->debug_area, DBF_WARNING);
274 DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
275
276 device->state = DASD_STATE_BASIC;
277 return 0;
278 }
279
280 /*
281 * Release the irq line for the device. Terminate any running i/o.
282 */
283 static int dasd_state_basic_to_known(struct dasd_device *device)
284 {
285 int rc;
286 if (device->block) {
287 dasd_profile_exit(&device->block->profile);
288 if (device->block->debugfs_dentry)
289 debugfs_remove(device->block->debugfs_dentry);
290 dasd_gendisk_free(device->block);
291 dasd_block_clear_timer(device->block);
292 }
293 rc = dasd_flush_device_queue(device);
294 if (rc)
295 return rc;
296 dasd_device_clear_timer(device);
297 dasd_profile_exit(&device->profile);
298 if (device->debugfs_dentry)
299 debugfs_remove(device->debugfs_dentry);
300
301 DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
302 if (device->debug_area != NULL) {
303 debug_unregister(device->debug_area);
304 device->debug_area = NULL;
305 }
306 device->state = DASD_STATE_KNOWN;
307 return 0;
308 }
309
310 /*
311 * Do the initial analysis. The do_analysis function may return
312 * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
313 * until the discipline decides to continue the startup sequence
314 * by calling the function dasd_change_state. The eckd disciplines
315 * uses this to start a ccw that detects the format. The completion
316 * interrupt for this detection ccw uses the kernel event daemon to
317 * trigger the call to dasd_change_state. All this is done in the
318 * discipline code, see dasd_eckd.c.
319 * After the analysis ccw is done (do_analysis returned 0) the block
320 * device is setup.
321 * In case the analysis returns an error, the device setup is stopped
322 * (a fake disk was already added to allow formatting).
323 */
324 static int dasd_state_basic_to_ready(struct dasd_device *device)
325 {
326 int rc;
327 struct dasd_block *block;
328
329 rc = 0;
330 block = device->block;
331 /* make disk known with correct capacity */
332 if (block) {
333 if (block->base->discipline->do_analysis != NULL)
334 rc = block->base->discipline->do_analysis(block);
335 if (rc) {
336 if (rc != -EAGAIN)
337 device->state = DASD_STATE_UNFMT;
338 return rc;
339 }
340 dasd_setup_queue(block);
341 set_capacity(block->gdp,
342 block->blocks << block->s2b_shift);
343 device->state = DASD_STATE_READY;
344 rc = dasd_scan_partitions(block);
345 if (rc)
346 device->state = DASD_STATE_BASIC;
347 } else {
348 device->state = DASD_STATE_READY;
349 }
350 return rc;
351 }
352
353 /*
354 * Remove device from block device layer. Destroy dirty buffers.
355 * Forget format information. Check if the target level is basic
356 * and if it is create fake disk for formatting.
357 */
358 static int dasd_state_ready_to_basic(struct dasd_device *device)
359 {
360 int rc;
361
362 device->state = DASD_STATE_BASIC;
363 if (device->block) {
364 struct dasd_block *block = device->block;
365 rc = dasd_flush_block_queue(block);
366 if (rc) {
367 device->state = DASD_STATE_READY;
368 return rc;
369 }
370 dasd_flush_request_queue(block);
371 dasd_destroy_partitions(block);
372 block->blocks = 0;
373 block->bp_block = 0;
374 block->s2b_shift = 0;
375 }
376 return 0;
377 }
378
379 /*
380 * Back to basic.
381 */
382 static int dasd_state_unfmt_to_basic(struct dasd_device *device)
383 {
384 device->state = DASD_STATE_BASIC;
385 return 0;
386 }
387
388 /*
389 * Make the device online and schedule the bottom half to start
390 * the requeueing of requests from the linux request queue to the
391 * ccw queue.
392 */
393 static int
394 dasd_state_ready_to_online(struct dasd_device * device)
395 {
396 int rc;
397 struct gendisk *disk;
398 struct disk_part_iter piter;
399 struct hd_struct *part;
400
401 if (device->discipline->ready_to_online) {
402 rc = device->discipline->ready_to_online(device);
403 if (rc)
404 return rc;
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 disk = device->block->gdp;
411 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
412 return 0;
413 }
414 disk = device->block->bdev->bd_disk;
415 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
416 while ((part = disk_part_iter_next(&piter)))
417 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
418 disk_part_iter_exit(&piter);
419 }
420 return 0;
421 }
422
423 /*
424 * Stop the requeueing of requests again.
425 */
426 static int dasd_state_online_to_ready(struct dasd_device *device)
427 {
428 int rc;
429 struct gendisk *disk;
430 struct disk_part_iter piter;
431 struct hd_struct *part;
432
433 if (device->discipline->online_to_ready) {
434 rc = device->discipline->online_to_ready(device);
435 if (rc)
436 return rc;
437 }
438 device->state = DASD_STATE_READY;
439 if (device->block && !(device->features & DASD_FEATURE_USERAW)) {
440 disk = device->block->bdev->bd_disk;
441 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
442 while ((part = disk_part_iter_next(&piter)))
443 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
444 disk_part_iter_exit(&piter);
445 }
446 return 0;
447 }
448
449 /*
450 * Device startup state changes.
451 */
452 static int dasd_increase_state(struct dasd_device *device)
453 {
454 int rc;
455
456 rc = 0;
457 if (device->state == DASD_STATE_NEW &&
458 device->target >= DASD_STATE_KNOWN)
459 rc = dasd_state_new_to_known(device);
460
461 if (!rc &&
462 device->state == DASD_STATE_KNOWN &&
463 device->target >= DASD_STATE_BASIC)
464 rc = dasd_state_known_to_basic(device);
465
466 if (!rc &&
467 device->state == DASD_STATE_BASIC &&
468 device->target >= DASD_STATE_READY)
469 rc = dasd_state_basic_to_ready(device);
470
471 if (!rc &&
472 device->state == DASD_STATE_UNFMT &&
473 device->target > DASD_STATE_UNFMT)
474 rc = -EPERM;
475
476 if (!rc &&
477 device->state == DASD_STATE_READY &&
478 device->target >= DASD_STATE_ONLINE)
479 rc = dasd_state_ready_to_online(device);
480
481 return rc;
482 }
483
484 /*
485 * Device shutdown state changes.
486 */
487 static int dasd_decrease_state(struct dasd_device *device)
488 {
489 int rc;
490
491 rc = 0;
492 if (device->state == DASD_STATE_ONLINE &&
493 device->target <= DASD_STATE_READY)
494 rc = dasd_state_online_to_ready(device);
495
496 if (!rc &&
497 device->state == DASD_STATE_READY &&
498 device->target <= DASD_STATE_BASIC)
499 rc = dasd_state_ready_to_basic(device);
500
501 if (!rc &&
502 device->state == DASD_STATE_UNFMT &&
503 device->target <= DASD_STATE_BASIC)
504 rc = dasd_state_unfmt_to_basic(device);
505
506 if (!rc &&
507 device->state == DASD_STATE_BASIC &&
508 device->target <= DASD_STATE_KNOWN)
509 rc = dasd_state_basic_to_known(device);
510
511 if (!rc &&
512 device->state == DASD_STATE_KNOWN &&
513 device->target <= DASD_STATE_NEW)
514 rc = dasd_state_known_to_new(device);
515
516 return rc;
517 }
518
519 /*
520 * This is the main startup/shutdown routine.
521 */
522 static void dasd_change_state(struct dasd_device *device)
523 {
524 int rc;
525
526 if (device->state == device->target)
527 /* Already where we want to go today... */
528 return;
529 if (device->state < device->target)
530 rc = dasd_increase_state(device);
531 else
532 rc = dasd_decrease_state(device);
533 if (rc == -EAGAIN)
534 return;
535 if (rc)
536 device->target = device->state;
537
538 if (device->state == device->target)
539 wake_up(&dasd_init_waitq);
540
541 /* let user-space know that the device status changed */
542 kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
543 }
544
545 /*
546 * Kick starter for devices that did not complete the startup/shutdown
547 * procedure or were sleeping because of a pending state.
548 * dasd_kick_device will schedule a call do do_kick_device to the kernel
549 * event daemon.
550 */
551 static void do_kick_device(struct work_struct *work)
552 {
553 struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
554 mutex_lock(&device->state_mutex);
555 dasd_change_state(device);
556 mutex_unlock(&device->state_mutex);
557 dasd_schedule_device_bh(device);
558 dasd_put_device(device);
559 }
560
561 void dasd_kick_device(struct dasd_device *device)
562 {
563 dasd_get_device(device);
564 /* queue call to dasd_kick_device to the kernel event daemon. */
565 schedule_work(&device->kick_work);
566 }
567
568 /*
569 * dasd_reload_device will schedule a call do do_reload_device to the kernel
570 * event daemon.
571 */
572 static void do_reload_device(struct work_struct *work)
573 {
574 struct dasd_device *device = container_of(work, struct dasd_device,
575 reload_device);
576 device->discipline->reload(device);
577 dasd_put_device(device);
578 }
579
580 void dasd_reload_device(struct dasd_device *device)
581 {
582 dasd_get_device(device);
583 /* queue call to dasd_reload_device to the kernel event daemon. */
584 schedule_work(&device->reload_device);
585 }
586 EXPORT_SYMBOL(dasd_reload_device);
587
588 /*
589 * dasd_restore_device will schedule a call do do_restore_device to the kernel
590 * event daemon.
591 */
592 static void do_restore_device(struct work_struct *work)
593 {
594 struct dasd_device *device = container_of(work, struct dasd_device,
595 restore_device);
596 device->cdev->drv->restore(device->cdev);
597 dasd_put_device(device);
598 }
599
600 void dasd_restore_device(struct dasd_device *device)
601 {
602 dasd_get_device(device);
603 /* queue call to dasd_restore_device to the kernel event daemon. */
604 schedule_work(&device->restore_device);
605 }
606
607 /*
608 * Set the target state for a device and starts the state change.
609 */
610 void dasd_set_target_state(struct dasd_device *device, int target)
611 {
612 dasd_get_device(device);
613 mutex_lock(&device->state_mutex);
614 /* If we are in probeonly mode stop at DASD_STATE_READY. */
615 if (dasd_probeonly && target > DASD_STATE_READY)
616 target = DASD_STATE_READY;
617 if (device->target != target) {
618 if (device->state == target)
619 wake_up(&dasd_init_waitq);
620 device->target = target;
621 }
622 if (device->state != device->target)
623 dasd_change_state(device);
624 mutex_unlock(&device->state_mutex);
625 dasd_put_device(device);
626 }
627
628 /*
629 * Enable devices with device numbers in [from..to].
630 */
631 static inline int _wait_for_device(struct dasd_device *device)
632 {
633 return (device->state == device->target);
634 }
635
636 void dasd_enable_device(struct dasd_device *device)
637 {
638 dasd_set_target_state(device, DASD_STATE_ONLINE);
639 if (device->state <= DASD_STATE_KNOWN)
640 /* No discipline for device found. */
641 dasd_set_target_state(device, DASD_STATE_NEW);
642 /* Now wait for the devices to come up. */
643 wait_event(dasd_init_waitq, _wait_for_device(device));
644 }
645
646 /*
647 * SECTION: device operation (interrupt handler, start i/o, term i/o ...)
648 */
649
650 unsigned int dasd_global_profile_level = DASD_PROFILE_OFF;
651
652 #ifdef CONFIG_DASD_PROFILE
653 struct dasd_profile_info dasd_global_profile_data;
654 static struct dentry *dasd_global_profile_dentry;
655 static struct dentry *dasd_debugfs_global_entry;
656
657 /*
658 * Add profiling information for cqr before execution.
659 */
660 static void dasd_profile_start(struct dasd_block *block,
661 struct dasd_ccw_req *cqr,
662 struct request *req)
663 {
664 struct list_head *l;
665 unsigned int counter;
666 struct dasd_device *device;
667
668 /* count the length of the chanq for statistics */
669 counter = 0;
670 if (dasd_global_profile_level || block->profile.data)
671 list_for_each(l, &block->ccw_queue)
672 if (++counter >= 31)
673 break;
674
675 if (dasd_global_profile_level) {
676 dasd_global_profile_data.dasd_io_nr_req[counter]++;
677 if (rq_data_dir(req) == READ)
678 dasd_global_profile_data.dasd_read_nr_req[counter]++;
679 }
680
681 spin_lock(&block->profile.lock);
682 if (block->profile.data)
683 block->profile.data->dasd_io_nr_req[counter]++;
684 if (rq_data_dir(req) == READ)
685 block->profile.data->dasd_read_nr_req[counter]++;
686 spin_unlock(&block->profile.lock);
687
688 /*
689 * We count the request for the start device, even though it may run on
690 * some other device due to error recovery. This way we make sure that
691 * we count each request only once.
692 */
693 device = cqr->startdev;
694 if (device->profile.data) {
695 counter = 1; /* request is not yet queued on the start device */
696 list_for_each(l, &device->ccw_queue)
697 if (++counter >= 31)
698 break;
699 }
700 spin_lock(&device->profile.lock);
701 if (device->profile.data) {
702 device->profile.data->dasd_io_nr_req[counter]++;
703 if (rq_data_dir(req) == READ)
704 device->profile.data->dasd_read_nr_req[counter]++;
705 }
706 spin_unlock(&device->profile.lock);
707 }
708
709 /*
710 * Add profiling information for cqr after execution.
711 */
712
713 #define dasd_profile_counter(value, index) \
714 { \
715 for (index = 0; index < 31 && value >> (2+index); index++) \
716 ; \
717 }
718
719 static void dasd_profile_end_add_data(struct dasd_profile_info *data,
720 int is_alias,
721 int is_tpm,
722 int is_read,
723 long sectors,
724 int sectors_ind,
725 int tottime_ind,
726 int tottimeps_ind,
727 int strtime_ind,
728 int irqtime_ind,
729 int irqtimeps_ind,
730 int endtime_ind)
731 {
732 /* in case of an overflow, reset the whole profile */
733 if (data->dasd_io_reqs == UINT_MAX) {
734 memset(data, 0, sizeof(*data));
735 getnstimeofday(&data->starttod);
736 }
737 data->dasd_io_reqs++;
738 data->dasd_io_sects += sectors;
739 if (is_alias)
740 data->dasd_io_alias++;
741 if (is_tpm)
742 data->dasd_io_tpm++;
743
744 data->dasd_io_secs[sectors_ind]++;
745 data->dasd_io_times[tottime_ind]++;
746 data->dasd_io_timps[tottimeps_ind]++;
747 data->dasd_io_time1[strtime_ind]++;
748 data->dasd_io_time2[irqtime_ind]++;
749 data->dasd_io_time2ps[irqtimeps_ind]++;
750 data->dasd_io_time3[endtime_ind]++;
751
752 if (is_read) {
753 data->dasd_read_reqs++;
754 data->dasd_read_sects += sectors;
755 if (is_alias)
756 data->dasd_read_alias++;
757 if (is_tpm)
758 data->dasd_read_tpm++;
759 data->dasd_read_secs[sectors_ind]++;
760 data->dasd_read_times[tottime_ind]++;
761 data->dasd_read_time1[strtime_ind]++;
762 data->dasd_read_time2[irqtime_ind]++;
763 data->dasd_read_time3[endtime_ind]++;
764 }
765 }
766
767 static void dasd_profile_end(struct dasd_block *block,
768 struct dasd_ccw_req *cqr,
769 struct request *req)
770 {
771 long strtime, irqtime, endtime, tottime; /* in microseconds */
772 long tottimeps, sectors;
773 struct dasd_device *device;
774 int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind;
775 int irqtime_ind, irqtimeps_ind, endtime_ind;
776
777 device = cqr->startdev;
778 if (!(dasd_global_profile_level ||
779 block->profile.data ||
780 device->profile.data))
781 return;
782
783 sectors = blk_rq_sectors(req);
784 if (!cqr->buildclk || !cqr->startclk ||
785 !cqr->stopclk || !cqr->endclk ||
786 !sectors)
787 return;
788
789 strtime = ((cqr->startclk - cqr->buildclk) >> 12);
790 irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
791 endtime = ((cqr->endclk - cqr->stopclk) >> 12);
792 tottime = ((cqr->endclk - cqr->buildclk) >> 12);
793 tottimeps = tottime / sectors;
794
795 dasd_profile_counter(sectors, sectors_ind);
796 dasd_profile_counter(tottime, tottime_ind);
797 dasd_profile_counter(tottimeps, tottimeps_ind);
798 dasd_profile_counter(strtime, strtime_ind);
799 dasd_profile_counter(irqtime, irqtime_ind);
800 dasd_profile_counter(irqtime / sectors, irqtimeps_ind);
801 dasd_profile_counter(endtime, endtime_ind);
802
803 if (dasd_global_profile_level) {
804 dasd_profile_end_add_data(&dasd_global_profile_data,
805 cqr->startdev != block->base,
806 cqr->cpmode == 1,
807 rq_data_dir(req) == READ,
808 sectors, sectors_ind, tottime_ind,
809 tottimeps_ind, strtime_ind,
810 irqtime_ind, irqtimeps_ind,
811 endtime_ind);
812 }
813
814 spin_lock(&block->profile.lock);
815 if (block->profile.data)
816 dasd_profile_end_add_data(block->profile.data,
817 cqr->startdev != block->base,
818 cqr->cpmode == 1,
819 rq_data_dir(req) == READ,
820 sectors, sectors_ind, tottime_ind,
821 tottimeps_ind, strtime_ind,
822 irqtime_ind, irqtimeps_ind,
823 endtime_ind);
824 spin_unlock(&block->profile.lock);
825
826 spin_lock(&device->profile.lock);
827 if (device->profile.data)
828 dasd_profile_end_add_data(device->profile.data,
829 cqr->startdev != block->base,
830 cqr->cpmode == 1,
831 rq_data_dir(req) == READ,
832 sectors, sectors_ind, tottime_ind,
833 tottimeps_ind, strtime_ind,
834 irqtime_ind, irqtimeps_ind,
835 endtime_ind);
836 spin_unlock(&device->profile.lock);
837 }
838
839 void dasd_profile_reset(struct dasd_profile *profile)
840 {
841 struct dasd_profile_info *data;
842
843 spin_lock_bh(&profile->lock);
844 data = profile->data;
845 if (!data) {
846 spin_unlock_bh(&profile->lock);
847 return;
848 }
849 memset(data, 0, sizeof(*data));
850 getnstimeofday(&data->starttod);
851 spin_unlock_bh(&profile->lock);
852 }
853
854 void dasd_global_profile_reset(void)
855 {
856 memset(&dasd_global_profile_data, 0, sizeof(dasd_global_profile_data));
857 getnstimeofday(&dasd_global_profile_data.starttod);
858 }
859
860 int dasd_profile_on(struct dasd_profile *profile)
861 {
862 struct dasd_profile_info *data;
863
864 data = kzalloc(sizeof(*data), GFP_KERNEL);
865 if (!data)
866 return -ENOMEM;
867 spin_lock_bh(&profile->lock);
868 if (profile->data) {
869 spin_unlock_bh(&profile->lock);
870 kfree(data);
871 return 0;
872 }
873 getnstimeofday(&data->starttod);
874 profile->data = data;
875 spin_unlock_bh(&profile->lock);
876 return 0;
877 }
878
879 void dasd_profile_off(struct dasd_profile *profile)
880 {
881 spin_lock_bh(&profile->lock);
882 kfree(profile->data);
883 profile->data = NULL;
884 spin_unlock_bh(&profile->lock);
885 }
886
887 char *dasd_get_user_string(const char __user *user_buf, size_t user_len)
888 {
889 char *buffer;
890
891 buffer = vmalloc(user_len + 1);
892 if (buffer == NULL)
893 return ERR_PTR(-ENOMEM);
894 if (copy_from_user(buffer, user_buf, user_len) != 0) {
895 vfree(buffer);
896 return ERR_PTR(-EFAULT);
897 }
898 /* got the string, now strip linefeed. */
899 if (buffer[user_len - 1] == '\n')
900 buffer[user_len - 1] = 0;
901 else
902 buffer[user_len] = 0;
903 return buffer;
904 }
905
906 static ssize_t dasd_stats_write(struct file *file,
907 const char __user *user_buf,
908 size_t user_len, loff_t *pos)
909 {
910 char *buffer, *str;
911 int rc;
912 struct seq_file *m = (struct seq_file *)file->private_data;
913 struct dasd_profile *prof = m->private;
914
915 if (user_len > 65536)
916 user_len = 65536;
917 buffer = dasd_get_user_string(user_buf, user_len);
918 if (IS_ERR(buffer))
919 return PTR_ERR(buffer);
920
921 str = skip_spaces(buffer);
922 rc = user_len;
923 if (strncmp(str, "reset", 5) == 0) {
924 dasd_profile_reset(prof);
925 } else if (strncmp(str, "on", 2) == 0) {
926 rc = dasd_profile_on(prof);
927 if (!rc)
928 rc = user_len;
929 } else if (strncmp(str, "off", 3) == 0) {
930 dasd_profile_off(prof);
931 } else
932 rc = -EINVAL;
933 vfree(buffer);
934 return rc;
935 }
936
937 static void dasd_stats_array(struct seq_file *m, unsigned int *array)
938 {
939 int i;
940
941 for (i = 0; i < 32; i++)
942 seq_printf(m, "%u ", array[i]);
943 seq_putc(m, '\n');
944 }
945
946 static void dasd_stats_seq_print(struct seq_file *m,
947 struct dasd_profile_info *data)
948 {
949 seq_printf(m, "start_time %ld.%09ld\n",
950 data->starttod.tv_sec, data->starttod.tv_nsec);
951 seq_printf(m, "total_requests %u\n", data->dasd_io_reqs);
952 seq_printf(m, "total_sectors %u\n", data->dasd_io_sects);
953 seq_printf(m, "total_pav %u\n", data->dasd_io_alias);
954 seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm);
955 seq_printf(m, "histogram_sectors ");
956 dasd_stats_array(m, data->dasd_io_secs);
957 seq_printf(m, "histogram_io_times ");
958 dasd_stats_array(m, data->dasd_io_times);
959 seq_printf(m, "histogram_io_times_weighted ");
960 dasd_stats_array(m, data->dasd_io_timps);
961 seq_printf(m, "histogram_time_build_to_ssch ");
962 dasd_stats_array(m, data->dasd_io_time1);
963 seq_printf(m, "histogram_time_ssch_to_irq ");
964 dasd_stats_array(m, data->dasd_io_time2);
965 seq_printf(m, "histogram_time_ssch_to_irq_weighted ");
966 dasd_stats_array(m, data->dasd_io_time2ps);
967 seq_printf(m, "histogram_time_irq_to_end ");
968 dasd_stats_array(m, data->dasd_io_time3);
969 seq_printf(m, "histogram_ccw_queue_length ");
970 dasd_stats_array(m, data->dasd_io_nr_req);
971 seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs);
972 seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects);
973 seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias);
974 seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm);
975 seq_printf(m, "histogram_read_sectors ");
976 dasd_stats_array(m, data->dasd_read_secs);
977 seq_printf(m, "histogram_read_times ");
978 dasd_stats_array(m, data->dasd_read_times);
979 seq_printf(m, "histogram_read_time_build_to_ssch ");
980 dasd_stats_array(m, data->dasd_read_time1);
981 seq_printf(m, "histogram_read_time_ssch_to_irq ");
982 dasd_stats_array(m, data->dasd_read_time2);
983 seq_printf(m, "histogram_read_time_irq_to_end ");
984 dasd_stats_array(m, data->dasd_read_time3);
985 seq_printf(m, "histogram_read_ccw_queue_length ");
986 dasd_stats_array(m, data->dasd_read_nr_req);
987 }
988
989 static int dasd_stats_show(struct seq_file *m, void *v)
990 {
991 struct dasd_profile *profile;
992 struct dasd_profile_info *data;
993
994 profile = m->private;
995 spin_lock_bh(&profile->lock);
996 data = profile->data;
997 if (!data) {
998 spin_unlock_bh(&profile->lock);
999 seq_printf(m, "disabled\n");
1000 return 0;
1001 }
1002 dasd_stats_seq_print(m, data);
1003 spin_unlock_bh(&profile->lock);
1004 return 0;
1005 }
1006
1007 static int dasd_stats_open(struct inode *inode, struct file *file)
1008 {
1009 struct dasd_profile *profile = inode->i_private;
1010 return single_open(file, dasd_stats_show, profile);
1011 }
1012
1013 static const struct file_operations dasd_stats_raw_fops = {
1014 .owner = THIS_MODULE,
1015 .open = dasd_stats_open,
1016 .read = seq_read,
1017 .llseek = seq_lseek,
1018 .release = single_release,
1019 .write = dasd_stats_write,
1020 };
1021
1022 static ssize_t dasd_stats_global_write(struct file *file,
1023 const char __user *user_buf,
1024 size_t user_len, loff_t *pos)
1025 {
1026 char *buffer, *str;
1027 ssize_t rc;
1028
1029 if (user_len > 65536)
1030 user_len = 65536;
1031 buffer = dasd_get_user_string(user_buf, user_len);
1032 if (IS_ERR(buffer))
1033 return PTR_ERR(buffer);
1034 str = skip_spaces(buffer);
1035 rc = user_len;
1036 if (strncmp(str, "reset", 5) == 0) {
1037 dasd_global_profile_reset();
1038 } else if (strncmp(str, "on", 2) == 0) {
1039 dasd_global_profile_reset();
1040 dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY;
1041 } else if (strncmp(str, "off", 3) == 0) {
1042 dasd_global_profile_level = DASD_PROFILE_OFF;
1043 } else
1044 rc = -EINVAL;
1045 vfree(buffer);
1046 return rc;
1047 }
1048
1049 static int dasd_stats_global_show(struct seq_file *m, void *v)
1050 {
1051 if (!dasd_global_profile_level) {
1052 seq_printf(m, "disabled\n");
1053 return 0;
1054 }
1055 dasd_stats_seq_print(m, &dasd_global_profile_data);
1056 return 0;
1057 }
1058
1059 static int dasd_stats_global_open(struct inode *inode, struct file *file)
1060 {
1061 return single_open(file, dasd_stats_global_show, NULL);
1062 }
1063
1064 static const struct file_operations dasd_stats_global_fops = {
1065 .owner = THIS_MODULE,
1066 .open = dasd_stats_global_open,
1067 .read = seq_read,
1068 .llseek = seq_lseek,
1069 .release = single_release,
1070 .write = dasd_stats_global_write,
1071 };
1072
1073 static void dasd_profile_init(struct dasd_profile *profile,
1074 struct dentry *base_dentry)
1075 {
1076 mode_t mode;
1077 struct dentry *pde;
1078
1079 if (!base_dentry)
1080 return;
1081 profile->dentry = NULL;
1082 profile->data = NULL;
1083 mode = (S_IRUSR | S_IWUSR | S_IFREG);
1084 pde = debugfs_create_file("statistics", mode, base_dentry,
1085 profile, &dasd_stats_raw_fops);
1086 if (pde && !IS_ERR(pde))
1087 profile->dentry = pde;
1088 return;
1089 }
1090
1091 static void dasd_profile_exit(struct dasd_profile *profile)
1092 {
1093 dasd_profile_off(profile);
1094 if (profile->dentry) {
1095 debugfs_remove(profile->dentry);
1096 profile->dentry = NULL;
1097 }
1098 }
1099
1100 static void dasd_statistics_removeroot(void)
1101 {
1102 dasd_global_profile_level = DASD_PROFILE_OFF;
1103 if (dasd_global_profile_dentry) {
1104 debugfs_remove(dasd_global_profile_dentry);
1105 dasd_global_profile_dentry = NULL;
1106 }
1107 if (dasd_debugfs_global_entry)
1108 debugfs_remove(dasd_debugfs_global_entry);
1109 if (dasd_debugfs_root_entry)
1110 debugfs_remove(dasd_debugfs_root_entry);
1111 }
1112
1113 static void dasd_statistics_createroot(void)
1114 {
1115 mode_t mode;
1116 struct dentry *pde;
1117
1118 dasd_debugfs_root_entry = NULL;
1119 dasd_debugfs_global_entry = NULL;
1120 dasd_global_profile_dentry = NULL;
1121 pde = debugfs_create_dir("dasd", NULL);
1122 if (!pde || IS_ERR(pde))
1123 goto error;
1124 dasd_debugfs_root_entry = pde;
1125 pde = debugfs_create_dir("global", dasd_debugfs_root_entry);
1126 if (!pde || IS_ERR(pde))
1127 goto error;
1128 dasd_debugfs_global_entry = pde;
1129
1130 mode = (S_IRUSR | S_IWUSR | S_IFREG);
1131 pde = debugfs_create_file("statistics", mode, dasd_debugfs_global_entry,
1132 NULL, &dasd_stats_global_fops);
1133 if (!pde || IS_ERR(pde))
1134 goto error;
1135 dasd_global_profile_dentry = pde;
1136 return;
1137
1138 error:
1139 DBF_EVENT(DBF_ERR, "%s",
1140 "Creation of the dasd debugfs interface failed");
1141 dasd_statistics_removeroot();
1142 return;
1143 }
1144
1145 #else
1146 #define dasd_profile_start(block, cqr, req) do {} while (0)
1147 #define dasd_profile_end(block, cqr, req) do {} while (0)
1148
1149 static void dasd_statistics_createroot(void)
1150 {
1151 return;
1152 }
1153
1154 static void dasd_statistics_removeroot(void)
1155 {
1156 return;
1157 }
1158
1159 int dasd_stats_generic_show(struct seq_file *m, void *v)
1160 {
1161 seq_printf(m, "Statistics are not activated in this kernel\n");
1162 return 0;
1163 }
1164
1165 static void dasd_profile_init(struct dasd_profile *profile,
1166 struct dentry *base_dentry)
1167 {
1168 return;
1169 }
1170
1171 static void dasd_profile_exit(struct dasd_profile *profile)
1172 {
1173 return;
1174 }
1175
1176 int dasd_profile_on(struct dasd_profile *profile)
1177 {
1178 return 0;
1179 }
1180
1181 #endif /* CONFIG_DASD_PROFILE */
1182
1183 /*
1184 * Allocate memory for a channel program with 'cplength' channel
1185 * command words and 'datasize' additional space. There are two
1186 * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed
1187 * memory and 2) dasd_smalloc_request uses the static ccw memory
1188 * that gets allocated for each device.
1189 */
1190 struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength,
1191 int datasize,
1192 struct dasd_device *device)
1193 {
1194 struct dasd_ccw_req *cqr;
1195
1196 /* Sanity checks */
1197 BUG_ON(datasize > PAGE_SIZE ||
1198 (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
1199
1200 cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
1201 if (cqr == NULL)
1202 return ERR_PTR(-ENOMEM);
1203 cqr->cpaddr = NULL;
1204 if (cplength > 0) {
1205 cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
1206 GFP_ATOMIC | GFP_DMA);
1207 if (cqr->cpaddr == NULL) {
1208 kfree(cqr);
1209 return ERR_PTR(-ENOMEM);
1210 }
1211 }
1212 cqr->data = NULL;
1213 if (datasize > 0) {
1214 cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA);
1215 if (cqr->data == NULL) {
1216 kfree(cqr->cpaddr);
1217 kfree(cqr);
1218 return ERR_PTR(-ENOMEM);
1219 }
1220 }
1221 cqr->magic = magic;
1222 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1223 dasd_get_device(device);
1224 return cqr;
1225 }
1226
1227 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength,
1228 int datasize,
1229 struct dasd_device *device)
1230 {
1231 unsigned long flags;
1232 struct dasd_ccw_req *cqr;
1233 char *data;
1234 int size;
1235
1236 size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
1237 if (cplength > 0)
1238 size += cplength * sizeof(struct ccw1);
1239 if (datasize > 0)
1240 size += datasize;
1241 spin_lock_irqsave(&device->mem_lock, flags);
1242 cqr = (struct dasd_ccw_req *)
1243 dasd_alloc_chunk(&device->ccw_chunks, size);
1244 spin_unlock_irqrestore(&device->mem_lock, flags);
1245 if (cqr == NULL)
1246 return ERR_PTR(-ENOMEM);
1247 memset(cqr, 0, sizeof(struct dasd_ccw_req));
1248 data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
1249 cqr->cpaddr = NULL;
1250 if (cplength > 0) {
1251 cqr->cpaddr = (struct ccw1 *) data;
1252 data += cplength*sizeof(struct ccw1);
1253 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
1254 }
1255 cqr->data = NULL;
1256 if (datasize > 0) {
1257 cqr->data = data;
1258 memset(cqr->data, 0, datasize);
1259 }
1260 cqr->magic = magic;
1261 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1262 dasd_get_device(device);
1263 return cqr;
1264 }
1265
1266 /*
1267 * Free memory of a channel program. This function needs to free all the
1268 * idal lists that might have been created by dasd_set_cda and the
1269 * struct dasd_ccw_req itself.
1270 */
1271 void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1272 {
1273 #ifdef CONFIG_64BIT
1274 struct ccw1 *ccw;
1275
1276 /* Clear any idals used for the request. */
1277 ccw = cqr->cpaddr;
1278 do {
1279 clear_normalized_cda(ccw);
1280 } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
1281 #endif
1282 kfree(cqr->cpaddr);
1283 kfree(cqr->data);
1284 kfree(cqr);
1285 dasd_put_device(device);
1286 }
1287
1288 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1289 {
1290 unsigned long flags;
1291
1292 spin_lock_irqsave(&device->mem_lock, flags);
1293 dasd_free_chunk(&device->ccw_chunks, cqr);
1294 spin_unlock_irqrestore(&device->mem_lock, flags);
1295 dasd_put_device(device);
1296 }
1297
1298 /*
1299 * Check discipline magic in cqr.
1300 */
1301 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
1302 {
1303 struct dasd_device *device;
1304
1305 if (cqr == NULL)
1306 return -EINVAL;
1307 device = cqr->startdev;
1308 if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
1309 DBF_DEV_EVENT(DBF_WARNING, device,
1310 " dasd_ccw_req 0x%08x magic doesn't match"
1311 " discipline 0x%08x",
1312 cqr->magic,
1313 *(unsigned int *) device->discipline->name);
1314 return -EINVAL;
1315 }
1316 return 0;
1317 }
1318
1319 /*
1320 * Terminate the current i/o and set the request to clear_pending.
1321 * Timer keeps device runnig.
1322 * ccw_device_clear can fail if the i/o subsystem
1323 * is in a bad mood.
1324 */
1325 int dasd_term_IO(struct dasd_ccw_req *cqr)
1326 {
1327 struct dasd_device *device;
1328 int retries, rc;
1329 char errorstring[ERRORLENGTH];
1330
1331 /* Check the cqr */
1332 rc = dasd_check_cqr(cqr);
1333 if (rc)
1334 return rc;
1335 retries = 0;
1336 device = (struct dasd_device *) cqr->startdev;
1337 while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
1338 rc = ccw_device_clear(device->cdev, (long) cqr);
1339 switch (rc) {
1340 case 0: /* termination successful */
1341 cqr->status = DASD_CQR_CLEAR_PENDING;
1342 cqr->stopclk = get_clock();
1343 cqr->starttime = 0;
1344 DBF_DEV_EVENT(DBF_DEBUG, device,
1345 "terminate cqr %p successful",
1346 cqr);
1347 break;
1348 case -ENODEV:
1349 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1350 "device gone, retry");
1351 break;
1352 case -EIO:
1353 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1354 "I/O error, retry");
1355 break;
1356 case -EINVAL:
1357 case -EBUSY:
1358 DBF_DEV_EVENT(DBF_ERR, device, "%s",
1359 "device busy, retry later");
1360 break;
1361 default:
1362 /* internal error 10 - unknown rc*/
1363 snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
1364 dev_err(&device->cdev->dev, "An error occurred in the "
1365 "DASD device driver, reason=%s\n", errorstring);
1366 BUG();
1367 break;
1368 }
1369 retries++;
1370 }
1371 dasd_schedule_device_bh(device);
1372 return rc;
1373 }
1374
1375 /*
1376 * Start the i/o. This start_IO can fail if the channel is really busy.
1377 * In that case set up a timer to start the request later.
1378 */
1379 int dasd_start_IO(struct dasd_ccw_req *cqr)
1380 {
1381 struct dasd_device *device;
1382 int rc;
1383 char errorstring[ERRORLENGTH];
1384
1385 /* Check the cqr */
1386 rc = dasd_check_cqr(cqr);
1387 if (rc) {
1388 cqr->intrc = rc;
1389 return rc;
1390 }
1391 device = (struct dasd_device *) cqr->startdev;
1392 if (((cqr->block &&
1393 test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) ||
1394 test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) &&
1395 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
1396 DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p "
1397 "because of stolen lock", cqr);
1398 cqr->status = DASD_CQR_ERROR;
1399 cqr->intrc = -EPERM;
1400 return -EPERM;
1401 }
1402 if (cqr->retries < 0) {
1403 /* internal error 14 - start_IO run out of retries */
1404 sprintf(errorstring, "14 %p", cqr);
1405 dev_err(&device->cdev->dev, "An error occurred in the DASD "
1406 "device driver, reason=%s\n", errorstring);
1407 cqr->status = DASD_CQR_ERROR;
1408 return -EIO;
1409 }
1410 cqr->startclk = get_clock();
1411 cqr->starttime = jiffies;
1412 cqr->retries--;
1413 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1414 cqr->lpm &= device->path_data.opm;
1415 if (!cqr->lpm)
1416 cqr->lpm = device->path_data.opm;
1417 }
1418 if (cqr->cpmode == 1) {
1419 rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
1420 (long) cqr, cqr->lpm);
1421 } else {
1422 rc = ccw_device_start(device->cdev, cqr->cpaddr,
1423 (long) cqr, cqr->lpm, 0);
1424 }
1425 switch (rc) {
1426 case 0:
1427 cqr->status = DASD_CQR_IN_IO;
1428 break;
1429 case -EBUSY:
1430 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1431 "start_IO: device busy, retry later");
1432 break;
1433 case -ETIMEDOUT:
1434 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1435 "start_IO: request timeout, retry later");
1436 break;
1437 case -EACCES:
1438 /* -EACCES indicates that the request used only a subset of the
1439 * available paths and all these paths are gone. If the lpm of
1440 * this request was only a subset of the opm (e.g. the ppm) then
1441 * we just do a retry with all available paths.
1442 * If we already use the full opm, something is amiss, and we
1443 * need a full path verification.
1444 */
1445 if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1446 DBF_DEV_EVENT(DBF_WARNING, device,
1447 "start_IO: selected paths gone (%x)",
1448 cqr->lpm);
1449 } else if (cqr->lpm != device->path_data.opm) {
1450 cqr->lpm = device->path_data.opm;
1451 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
1452 "start_IO: selected paths gone,"
1453 " retry on all paths");
1454 } else {
1455 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1456 "start_IO: all paths in opm gone,"
1457 " do path verification");
1458 dasd_generic_last_path_gone(device);
1459 device->path_data.opm = 0;
1460 device->path_data.ppm = 0;
1461 device->path_data.npm = 0;
1462 device->path_data.tbvpm =
1463 ccw_device_get_path_mask(device->cdev);
1464 }
1465 break;
1466 case -ENODEV:
1467 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1468 "start_IO: -ENODEV device gone, retry");
1469 break;
1470 case -EIO:
1471 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1472 "start_IO: -EIO device gone, retry");
1473 break;
1474 case -EINVAL:
1475 /* most likely caused in power management context */
1476 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1477 "start_IO: -EINVAL device currently "
1478 "not accessible");
1479 break;
1480 default:
1481 /* internal error 11 - unknown rc */
1482 snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
1483 dev_err(&device->cdev->dev,
1484 "An error occurred in the DASD device driver, "
1485 "reason=%s\n", errorstring);
1486 BUG();
1487 break;
1488 }
1489 cqr->intrc = rc;
1490 return rc;
1491 }
1492
1493 /*
1494 * Timeout function for dasd devices. This is used for different purposes
1495 * 1) missing interrupt handler for normal operation
1496 * 2) delayed start of request where start_IO failed with -EBUSY
1497 * 3) timeout for missing state change interrupts
1498 * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
1499 * DASD_CQR_QUEUED for 2) and 3).
1500 */
1501 static void dasd_device_timeout(unsigned long ptr)
1502 {
1503 unsigned long flags;
1504 struct dasd_device *device;
1505
1506 device = (struct dasd_device *) ptr;
1507 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1508 /* re-activate request queue */
1509 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1510 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1511 dasd_schedule_device_bh(device);
1512 }
1513
1514 /*
1515 * Setup timeout for a device in jiffies.
1516 */
1517 void dasd_device_set_timer(struct dasd_device *device, int expires)
1518 {
1519 if (expires == 0)
1520 del_timer(&device->timer);
1521 else
1522 mod_timer(&device->timer, jiffies + expires);
1523 }
1524
1525 /*
1526 * Clear timeout for a device.
1527 */
1528 void dasd_device_clear_timer(struct dasd_device *device)
1529 {
1530 del_timer(&device->timer);
1531 }
1532
1533 static void dasd_handle_killed_request(struct ccw_device *cdev,
1534 unsigned long intparm)
1535 {
1536 struct dasd_ccw_req *cqr;
1537 struct dasd_device *device;
1538
1539 if (!intparm)
1540 return;
1541 cqr = (struct dasd_ccw_req *) intparm;
1542 if (cqr->status != DASD_CQR_IN_IO) {
1543 DBF_EVENT_DEVID(DBF_DEBUG, cdev,
1544 "invalid status in handle_killed_request: "
1545 "%02x", cqr->status);
1546 return;
1547 }
1548
1549 device = dasd_device_from_cdev_locked(cdev);
1550 if (IS_ERR(device)) {
1551 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1552 "unable to get device from cdev");
1553 return;
1554 }
1555
1556 if (!cqr->startdev ||
1557 device != cqr->startdev ||
1558 strncmp(cqr->startdev->discipline->ebcname,
1559 (char *) &cqr->magic, 4)) {
1560 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1561 "invalid device in request");
1562 dasd_put_device(device);
1563 return;
1564 }
1565
1566 /* Schedule request to be retried. */
1567 cqr->status = DASD_CQR_QUEUED;
1568
1569 dasd_device_clear_timer(device);
1570 dasd_schedule_device_bh(device);
1571 dasd_put_device(device);
1572 }
1573
1574 void dasd_generic_handle_state_change(struct dasd_device *device)
1575 {
1576 /* First of all start sense subsystem status request. */
1577 dasd_eer_snss(device);
1578
1579 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1580 dasd_schedule_device_bh(device);
1581 if (device->block)
1582 dasd_schedule_block_bh(device->block);
1583 }
1584
1585 /*
1586 * Interrupt handler for "normal" ssch-io based dasd devices.
1587 */
1588 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
1589 struct irb *irb)
1590 {
1591 struct dasd_ccw_req *cqr, *next;
1592 struct dasd_device *device;
1593 unsigned long long now;
1594 int expires;
1595
1596 if (IS_ERR(irb)) {
1597 switch (PTR_ERR(irb)) {
1598 case -EIO:
1599 break;
1600 case -ETIMEDOUT:
1601 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1602 "request timed out\n", __func__);
1603 break;
1604 default:
1605 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1606 "unknown error %ld\n", __func__,
1607 PTR_ERR(irb));
1608 }
1609 dasd_handle_killed_request(cdev, intparm);
1610 return;
1611 }
1612
1613 now = get_clock();
1614 cqr = (struct dasd_ccw_req *) intparm;
1615 /* check for conditions that should be handled immediately */
1616 if (!cqr ||
1617 !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1618 scsw_cstat(&irb->scsw) == 0)) {
1619 if (cqr)
1620 memcpy(&cqr->irb, irb, sizeof(*irb));
1621 device = dasd_device_from_cdev_locked(cdev);
1622 if (IS_ERR(device))
1623 return;
1624 /* ignore unsolicited interrupts for DIAG discipline */
1625 if (device->discipline == dasd_diag_discipline_pointer) {
1626 dasd_put_device(device);
1627 return;
1628 }
1629 device->discipline->dump_sense_dbf(device, irb, "int");
1630 if (device->features & DASD_FEATURE_ERPLOG)
1631 device->discipline->dump_sense(device, cqr, irb);
1632 device->discipline->check_for_device_change(device, cqr, irb);
1633 dasd_put_device(device);
1634 }
1635 if (!cqr)
1636 return;
1637
1638 device = (struct dasd_device *) cqr->startdev;
1639 if (!device ||
1640 strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
1641 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1642 "invalid device in request");
1643 return;
1644 }
1645
1646 /* Check for clear pending */
1647 if (cqr->status == DASD_CQR_CLEAR_PENDING &&
1648 scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
1649 cqr->status = DASD_CQR_CLEARED;
1650 dasd_device_clear_timer(device);
1651 wake_up(&dasd_flush_wq);
1652 dasd_schedule_device_bh(device);
1653 return;
1654 }
1655
1656 /* check status - the request might have been killed by dyn detach */
1657 if (cqr->status != DASD_CQR_IN_IO) {
1658 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
1659 "status %02x", dev_name(&cdev->dev), cqr->status);
1660 return;
1661 }
1662
1663 next = NULL;
1664 expires = 0;
1665 if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1666 scsw_cstat(&irb->scsw) == 0) {
1667 /* request was completed successfully */
1668 cqr->status = DASD_CQR_SUCCESS;
1669 cqr->stopclk = now;
1670 /* Start first request on queue if possible -> fast_io. */
1671 if (cqr->devlist.next != &device->ccw_queue) {
1672 next = list_entry(cqr->devlist.next,
1673 struct dasd_ccw_req, devlist);
1674 }
1675 } else { /* error */
1676 /*
1677 * If we don't want complex ERP for this request, then just
1678 * reset this and retry it in the fastpath
1679 */
1680 if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
1681 cqr->retries > 0) {
1682 if (cqr->lpm == device->path_data.opm)
1683 DBF_DEV_EVENT(DBF_DEBUG, device,
1684 "default ERP in fastpath "
1685 "(%i retries left)",
1686 cqr->retries);
1687 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))
1688 cqr->lpm = device->path_data.opm;
1689 cqr->status = DASD_CQR_QUEUED;
1690 next = cqr;
1691 } else
1692 cqr->status = DASD_CQR_ERROR;
1693 }
1694 if (next && (next->status == DASD_CQR_QUEUED) &&
1695 (!device->stopped)) {
1696 if (device->discipline->start_IO(next) == 0)
1697 expires = next->expires;
1698 }
1699 if (expires != 0)
1700 dasd_device_set_timer(device, expires);
1701 else
1702 dasd_device_clear_timer(device);
1703 dasd_schedule_device_bh(device);
1704 }
1705
1706 enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb)
1707 {
1708 struct dasd_device *device;
1709
1710 device = dasd_device_from_cdev_locked(cdev);
1711
1712 if (IS_ERR(device))
1713 goto out;
1714 if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
1715 device->state != device->target ||
1716 !device->discipline->check_for_device_change){
1717 dasd_put_device(device);
1718 goto out;
1719 }
1720 if (device->discipline->dump_sense_dbf)
1721 device->discipline->dump_sense_dbf(device, irb, "uc");
1722 device->discipline->check_for_device_change(device, NULL, irb);
1723 dasd_put_device(device);
1724 out:
1725 return UC_TODO_RETRY;
1726 }
1727 EXPORT_SYMBOL_GPL(dasd_generic_uc_handler);
1728
1729 /*
1730 * If we have an error on a dasd_block layer request then we cancel
1731 * and return all further requests from the same dasd_block as well.
1732 */
1733 static void __dasd_device_recovery(struct dasd_device *device,
1734 struct dasd_ccw_req *ref_cqr)
1735 {
1736 struct list_head *l, *n;
1737 struct dasd_ccw_req *cqr;
1738
1739 /*
1740 * only requeue request that came from the dasd_block layer
1741 */
1742 if (!ref_cqr->block)
1743 return;
1744
1745 list_for_each_safe(l, n, &device->ccw_queue) {
1746 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1747 if (cqr->status == DASD_CQR_QUEUED &&
1748 ref_cqr->block == cqr->block) {
1749 cqr->status = DASD_CQR_CLEARED;
1750 }
1751 }
1752 };
1753
1754 /*
1755 * Remove those ccw requests from the queue that need to be returned
1756 * to the upper layer.
1757 */
1758 static void __dasd_device_process_ccw_queue(struct dasd_device *device,
1759 struct list_head *final_queue)
1760 {
1761 struct list_head *l, *n;
1762 struct dasd_ccw_req *cqr;
1763
1764 /* Process request with final status. */
1765 list_for_each_safe(l, n, &device->ccw_queue) {
1766 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1767
1768 /* Stop list processing at the first non-final request. */
1769 if (cqr->status == DASD_CQR_QUEUED ||
1770 cqr->status == DASD_CQR_IN_IO ||
1771 cqr->status == DASD_CQR_CLEAR_PENDING)
1772 break;
1773 if (cqr->status == DASD_CQR_ERROR) {
1774 __dasd_device_recovery(device, cqr);
1775 }
1776 /* Rechain finished requests to final queue */
1777 list_move_tail(&cqr->devlist, final_queue);
1778 }
1779 }
1780
1781 /*
1782 * the cqrs from the final queue are returned to the upper layer
1783 * by setting a dasd_block state and calling the callback function
1784 */
1785 static void __dasd_device_process_final_queue(struct dasd_device *device,
1786 struct list_head *final_queue)
1787 {
1788 struct list_head *l, *n;
1789 struct dasd_ccw_req *cqr;
1790 struct dasd_block *block;
1791 void (*callback)(struct dasd_ccw_req *, void *data);
1792 void *callback_data;
1793 char errorstring[ERRORLENGTH];
1794
1795 list_for_each_safe(l, n, final_queue) {
1796 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1797 list_del_init(&cqr->devlist);
1798 block = cqr->block;
1799 callback = cqr->callback;
1800 callback_data = cqr->callback_data;
1801 if (block)
1802 spin_lock_bh(&block->queue_lock);
1803 switch (cqr->status) {
1804 case DASD_CQR_SUCCESS:
1805 cqr->status = DASD_CQR_DONE;
1806 break;
1807 case DASD_CQR_ERROR:
1808 cqr->status = DASD_CQR_NEED_ERP;
1809 break;
1810 case DASD_CQR_CLEARED:
1811 cqr->status = DASD_CQR_TERMINATED;
1812 break;
1813 default:
1814 /* internal error 12 - wrong cqr status*/
1815 snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
1816 dev_err(&device->cdev->dev,
1817 "An error occurred in the DASD device driver, "
1818 "reason=%s\n", errorstring);
1819 BUG();
1820 }
1821 if (cqr->callback != NULL)
1822 (callback)(cqr, callback_data);
1823 if (block)
1824 spin_unlock_bh(&block->queue_lock);
1825 }
1826 }
1827
1828 /*
1829 * Take a look at the first request on the ccw queue and check
1830 * if it reached its expire time. If so, terminate the IO.
1831 */
1832 static void __dasd_device_check_expire(struct dasd_device *device)
1833 {
1834 struct dasd_ccw_req *cqr;
1835
1836 if (list_empty(&device->ccw_queue))
1837 return;
1838 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1839 if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
1840 (time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
1841 if (device->discipline->term_IO(cqr) != 0) {
1842 /* Hmpf, try again in 5 sec */
1843 dev_err(&device->cdev->dev,
1844 "cqr %p timed out (%lus) but cannot be "
1845 "ended, retrying in 5 s\n",
1846 cqr, (cqr->expires/HZ));
1847 cqr->expires += 5*HZ;
1848 dasd_device_set_timer(device, 5*HZ);
1849 } else {
1850 dev_err(&device->cdev->dev,
1851 "cqr %p timed out (%lus), %i retries "
1852 "remaining\n", cqr, (cqr->expires/HZ),
1853 cqr->retries);
1854 }
1855 }
1856 }
1857
1858 /*
1859 * Take a look at the first request on the ccw queue and check
1860 * if it needs to be started.
1861 */
1862 static void __dasd_device_start_head(struct dasd_device *device)
1863 {
1864 struct dasd_ccw_req *cqr;
1865 int rc;
1866
1867 if (list_empty(&device->ccw_queue))
1868 return;
1869 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1870 if (cqr->status != DASD_CQR_QUEUED)
1871 return;
1872 /* when device is stopped, return request to previous layer
1873 * exception: only the disconnect or unresumed bits are set and the
1874 * cqr is a path verification request
1875 */
1876 if (device->stopped &&
1877 !(!(device->stopped & ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
1878 && test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))) {
1879 cqr->intrc = -EAGAIN;
1880 cqr->status = DASD_CQR_CLEARED;
1881 dasd_schedule_device_bh(device);
1882 return;
1883 }
1884
1885 rc = device->discipline->start_IO(cqr);
1886 if (rc == 0)
1887 dasd_device_set_timer(device, cqr->expires);
1888 else if (rc == -EACCES) {
1889 dasd_schedule_device_bh(device);
1890 } else
1891 /* Hmpf, try again in 1/2 sec */
1892 dasd_device_set_timer(device, 50);
1893 }
1894
1895 static void __dasd_device_check_path_events(struct dasd_device *device)
1896 {
1897 int rc;
1898
1899 if (device->path_data.tbvpm) {
1900 if (device->stopped & ~(DASD_STOPPED_DC_WAIT |
1901 DASD_UNRESUMED_PM))
1902 return;
1903 rc = device->discipline->verify_path(
1904 device, device->path_data.tbvpm);
1905 if (rc)
1906 dasd_device_set_timer(device, 50);
1907 else
1908 device->path_data.tbvpm = 0;
1909 }
1910 };
1911
1912 /*
1913 * Go through all request on the dasd_device request queue,
1914 * terminate them on the cdev if necessary, and return them to the
1915 * submitting layer via callback.
1916 * Note:
1917 * Make sure that all 'submitting layers' still exist when
1918 * this function is called!. In other words, when 'device' is a base
1919 * device then all block layer requests must have been removed before
1920 * via dasd_flush_block_queue.
1921 */
1922 int dasd_flush_device_queue(struct dasd_device *device)
1923 {
1924 struct dasd_ccw_req *cqr, *n;
1925 int rc;
1926 struct list_head flush_queue;
1927
1928 INIT_LIST_HEAD(&flush_queue);
1929 spin_lock_irq(get_ccwdev_lock(device->cdev));
1930 rc = 0;
1931 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
1932 /* Check status and move request to flush_queue */
1933 switch (cqr->status) {
1934 case DASD_CQR_IN_IO:
1935 rc = device->discipline->term_IO(cqr);
1936 if (rc) {
1937 /* unable to terminate requeust */
1938 dev_err(&device->cdev->dev,
1939 "Flushing the DASD request queue "
1940 "failed for request %p\n", cqr);
1941 /* stop flush processing */
1942 goto finished;
1943 }
1944 break;
1945 case DASD_CQR_QUEUED:
1946 cqr->stopclk = get_clock();
1947 cqr->status = DASD_CQR_CLEARED;
1948 break;
1949 default: /* no need to modify the others */
1950 break;
1951 }
1952 list_move_tail(&cqr->devlist, &flush_queue);
1953 }
1954 finished:
1955 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1956 /*
1957 * After this point all requests must be in state CLEAR_PENDING,
1958 * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
1959 * one of the others.
1960 */
1961 list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
1962 wait_event(dasd_flush_wq,
1963 (cqr->status != DASD_CQR_CLEAR_PENDING));
1964 /*
1965 * Now set each request back to TERMINATED, DONE or NEED_ERP
1966 * and call the callback function of flushed requests
1967 */
1968 __dasd_device_process_final_queue(device, &flush_queue);
1969 return rc;
1970 }
1971
1972 /*
1973 * Acquire the device lock and process queues for the device.
1974 */
1975 static void dasd_device_tasklet(struct dasd_device *device)
1976 {
1977 struct list_head final_queue;
1978
1979 atomic_set (&device->tasklet_scheduled, 0);
1980 INIT_LIST_HEAD(&final_queue);
1981 spin_lock_irq(get_ccwdev_lock(device->cdev));
1982 /* Check expire time of first request on the ccw queue. */
1983 __dasd_device_check_expire(device);
1984 /* find final requests on ccw queue */
1985 __dasd_device_process_ccw_queue(device, &final_queue);
1986 __dasd_device_check_path_events(device);
1987 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1988 /* Now call the callback function of requests with final status */
1989 __dasd_device_process_final_queue(device, &final_queue);
1990 spin_lock_irq(get_ccwdev_lock(device->cdev));
1991 /* Now check if the head of the ccw queue needs to be started. */
1992 __dasd_device_start_head(device);
1993 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1994 dasd_put_device(device);
1995 }
1996
1997 /*
1998 * Schedules a call to dasd_tasklet over the device tasklet.
1999 */
2000 void dasd_schedule_device_bh(struct dasd_device *device)
2001 {
2002 /* Protect against rescheduling. */
2003 if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
2004 return;
2005 dasd_get_device(device);
2006 tasklet_hi_schedule(&device->tasklet);
2007 }
2008
2009 void dasd_device_set_stop_bits(struct dasd_device *device, int bits)
2010 {
2011 device->stopped |= bits;
2012 }
2013 EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits);
2014
2015 void dasd_device_remove_stop_bits(struct dasd_device *device, int bits)
2016 {
2017 device->stopped &= ~bits;
2018 if (!device->stopped)
2019 wake_up(&generic_waitq);
2020 }
2021 EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits);
2022
2023 /*
2024 * Queue a request to the head of the device ccw_queue.
2025 * Start the I/O if possible.
2026 */
2027 void dasd_add_request_head(struct dasd_ccw_req *cqr)
2028 {
2029 struct dasd_device *device;
2030 unsigned long flags;
2031
2032 device = cqr->startdev;
2033 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2034 cqr->status = DASD_CQR_QUEUED;
2035 list_add(&cqr->devlist, &device->ccw_queue);
2036 /* let the bh start the request to keep them in order */
2037 dasd_schedule_device_bh(device);
2038 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2039 }
2040
2041 /*
2042 * Queue a request to the tail of the device ccw_queue.
2043 * Start the I/O if possible.
2044 */
2045 void dasd_add_request_tail(struct dasd_ccw_req *cqr)
2046 {
2047 struct dasd_device *device;
2048 unsigned long flags;
2049
2050 device = cqr->startdev;
2051 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2052 cqr->status = DASD_CQR_QUEUED;
2053 list_add_tail(&cqr->devlist, &device->ccw_queue);
2054 /* let the bh start the request to keep them in order */
2055 dasd_schedule_device_bh(device);
2056 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2057 }
2058
2059 /*
2060 * Wakeup helper for the 'sleep_on' functions.
2061 */
2062 void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
2063 {
2064 spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2065 cqr->callback_data = DASD_SLEEPON_END_TAG;
2066 spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2067 wake_up(&generic_waitq);
2068 }
2069 EXPORT_SYMBOL_GPL(dasd_wakeup_cb);
2070
2071 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
2072 {
2073 struct dasd_device *device;
2074 int rc;
2075
2076 device = cqr->startdev;
2077 spin_lock_irq(get_ccwdev_lock(device->cdev));
2078 rc = (cqr->callback_data == DASD_SLEEPON_END_TAG);
2079 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2080 return rc;
2081 }
2082
2083 /*
2084 * checks if error recovery is necessary, returns 1 if yes, 0 otherwise.
2085 */
2086 static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr)
2087 {
2088 struct dasd_device *device;
2089 dasd_erp_fn_t erp_fn;
2090
2091 if (cqr->status == DASD_CQR_FILLED)
2092 return 0;
2093 device = cqr->startdev;
2094 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2095 if (cqr->status == DASD_CQR_TERMINATED) {
2096 device->discipline->handle_terminated_request(cqr);
2097 return 1;
2098 }
2099 if (cqr->status == DASD_CQR_NEED_ERP) {
2100 erp_fn = device->discipline->erp_action(cqr);
2101 erp_fn(cqr);
2102 return 1;
2103 }
2104 if (cqr->status == DASD_CQR_FAILED)
2105 dasd_log_sense(cqr, &cqr->irb);
2106 if (cqr->refers) {
2107 __dasd_process_erp(device, cqr);
2108 return 1;
2109 }
2110 }
2111 return 0;
2112 }
2113
2114 static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr)
2115 {
2116 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2117 if (cqr->refers) /* erp is not done yet */
2118 return 1;
2119 return ((cqr->status != DASD_CQR_DONE) &&
2120 (cqr->status != DASD_CQR_FAILED));
2121 } else
2122 return (cqr->status == DASD_CQR_FILLED);
2123 }
2124
2125 static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
2126 {
2127 struct dasd_device *device;
2128 int rc;
2129 struct list_head ccw_queue;
2130 struct dasd_ccw_req *cqr;
2131
2132 INIT_LIST_HEAD(&ccw_queue);
2133 maincqr->status = DASD_CQR_FILLED;
2134 device = maincqr->startdev;
2135 list_add(&maincqr->blocklist, &ccw_queue);
2136 for (cqr = maincqr; __dasd_sleep_on_loop_condition(cqr);
2137 cqr = list_first_entry(&ccw_queue,
2138 struct dasd_ccw_req, blocklist)) {
2139
2140 if (__dasd_sleep_on_erp(cqr))
2141 continue;
2142 if (cqr->status != DASD_CQR_FILLED) /* could be failed */
2143 continue;
2144 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2145 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2146 cqr->status = DASD_CQR_FAILED;
2147 cqr->intrc = -EPERM;
2148 continue;
2149 }
2150 /* Non-temporary stop condition will trigger fail fast */
2151 if (device->stopped & ~DASD_STOPPED_PENDING &&
2152 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2153 (!dasd_eer_enabled(device))) {
2154 cqr->status = DASD_CQR_FAILED;
2155 continue;
2156 }
2157 /* Don't try to start requests if device is stopped */
2158 if (interruptible) {
2159 rc = wait_event_interruptible(
2160 generic_waitq, !(device->stopped));
2161 if (rc == -ERESTARTSYS) {
2162 cqr->status = DASD_CQR_FAILED;
2163 maincqr->intrc = rc;
2164 continue;
2165 }
2166 } else
2167 wait_event(generic_waitq, !(device->stopped));
2168
2169 if (!cqr->callback)
2170 cqr->callback = dasd_wakeup_cb;
2171
2172 cqr->callback_data = DASD_SLEEPON_START_TAG;
2173 dasd_add_request_tail(cqr);
2174 if (interruptible) {
2175 rc = wait_event_interruptible(
2176 generic_waitq, _wait_for_wakeup(cqr));
2177 if (rc == -ERESTARTSYS) {
2178 dasd_cancel_req(cqr);
2179 /* wait (non-interruptible) for final status */
2180 wait_event(generic_waitq,
2181 _wait_for_wakeup(cqr));
2182 cqr->status = DASD_CQR_FAILED;
2183 maincqr->intrc = rc;
2184 continue;
2185 }
2186 } else
2187 wait_event(generic_waitq, _wait_for_wakeup(cqr));
2188 }
2189
2190 maincqr->endclk = get_clock();
2191 if ((maincqr->status != DASD_CQR_DONE) &&
2192 (maincqr->intrc != -ERESTARTSYS))
2193 dasd_log_sense(maincqr, &maincqr->irb);
2194 if (maincqr->status == DASD_CQR_DONE)
2195 rc = 0;
2196 else if (maincqr->intrc)
2197 rc = maincqr->intrc;
2198 else
2199 rc = -EIO;
2200 return rc;
2201 }
2202
2203 /*
2204 * Queue a request to the tail of the device ccw_queue and wait for
2205 * it's completion.
2206 */
2207 int dasd_sleep_on(struct dasd_ccw_req *cqr)
2208 {
2209 return _dasd_sleep_on(cqr, 0);
2210 }
2211
2212 /*
2213 * Queue a request to the tail of the device ccw_queue and wait
2214 * interruptible for it's completion.
2215 */
2216 int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
2217 {
2218 return _dasd_sleep_on(cqr, 1);
2219 }
2220
2221 /*
2222 * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
2223 * for eckd devices) the currently running request has to be terminated
2224 * and be put back to status queued, before the special request is added
2225 * to the head of the queue. Then the special request is waited on normally.
2226 */
2227 static inline int _dasd_term_running_cqr(struct dasd_device *device)
2228 {
2229 struct dasd_ccw_req *cqr;
2230 int rc;
2231
2232 if (list_empty(&device->ccw_queue))
2233 return 0;
2234 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2235 rc = device->discipline->term_IO(cqr);
2236 if (!rc)
2237 /*
2238 * CQR terminated because a more important request is pending.
2239 * Undo decreasing of retry counter because this is
2240 * not an error case.
2241 */
2242 cqr->retries++;
2243 return rc;
2244 }
2245
2246 int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
2247 {
2248 struct dasd_device *device;
2249 int rc;
2250
2251 device = cqr->startdev;
2252 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2253 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2254 cqr->status = DASD_CQR_FAILED;
2255 cqr->intrc = -EPERM;
2256 return -EIO;
2257 }
2258 spin_lock_irq(get_ccwdev_lock(device->cdev));
2259 rc = _dasd_term_running_cqr(device);
2260 if (rc) {
2261 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2262 return rc;
2263 }
2264 cqr->callback = dasd_wakeup_cb;
2265 cqr->callback_data = DASD_SLEEPON_START_TAG;
2266 cqr->status = DASD_CQR_QUEUED;
2267 /*
2268 * add new request as second
2269 * first the terminated cqr needs to be finished
2270 */
2271 list_add(&cqr->devlist, device->ccw_queue.next);
2272
2273 /* let the bh start the request to keep them in order */
2274 dasd_schedule_device_bh(device);
2275
2276 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2277
2278 wait_event(generic_waitq, _wait_for_wakeup(cqr));
2279
2280 if (cqr->status == DASD_CQR_DONE)
2281 rc = 0;
2282 else if (cqr->intrc)
2283 rc = cqr->intrc;
2284 else
2285 rc = -EIO;
2286 return rc;
2287 }
2288
2289 /*
2290 * Cancels a request that was started with dasd_sleep_on_req.
2291 * This is useful to timeout requests. The request will be
2292 * terminated if it is currently in i/o.
2293 * Returns 1 if the request has been terminated.
2294 * 0 if there was no need to terminate the request (not started yet)
2295 * negative error code if termination failed
2296 * Cancellation of a request is an asynchronous operation! The calling
2297 * function has to wait until the request is properly returned via callback.
2298 */
2299 int dasd_cancel_req(struct dasd_ccw_req *cqr)
2300 {
2301 struct dasd_device *device = cqr->startdev;
2302 unsigned long flags;
2303 int rc;
2304
2305 rc = 0;
2306 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2307 switch (cqr->status) {
2308 case DASD_CQR_QUEUED:
2309 /* request was not started - just set to cleared */
2310 cqr->status = DASD_CQR_CLEARED;
2311 break;
2312 case DASD_CQR_IN_IO:
2313 /* request in IO - terminate IO and release again */
2314 rc = device->discipline->term_IO(cqr);
2315 if (rc) {
2316 dev_err(&device->cdev->dev,
2317 "Cancelling request %p failed with rc=%d\n",
2318 cqr, rc);
2319 } else {
2320 cqr->stopclk = get_clock();
2321 }
2322 break;
2323 default: /* already finished or clear pending - do nothing */
2324 break;
2325 }
2326 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2327 dasd_schedule_device_bh(device);
2328 return rc;
2329 }
2330
2331
2332 /*
2333 * SECTION: Operations of the dasd_block layer.
2334 */
2335
2336 /*
2337 * Timeout function for dasd_block. This is used when the block layer
2338 * is waiting for something that may not come reliably, (e.g. a state
2339 * change interrupt)
2340 */
2341 static void dasd_block_timeout(unsigned long ptr)
2342 {
2343 unsigned long flags;
2344 struct dasd_block *block;
2345
2346 block = (struct dasd_block *) ptr;
2347 spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
2348 /* re-activate request queue */
2349 dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING);
2350 spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
2351 dasd_schedule_block_bh(block);
2352 }
2353
2354 /*
2355 * Setup timeout for a dasd_block in jiffies.
2356 */
2357 void dasd_block_set_timer(struct dasd_block *block, int expires)
2358 {
2359 if (expires == 0)
2360 del_timer(&block->timer);
2361 else
2362 mod_timer(&block->timer, jiffies + expires);
2363 }
2364
2365 /*
2366 * Clear timeout for a dasd_block.
2367 */
2368 void dasd_block_clear_timer(struct dasd_block *block)
2369 {
2370 del_timer(&block->timer);
2371 }
2372
2373 /*
2374 * Process finished error recovery ccw.
2375 */
2376 static void __dasd_process_erp(struct dasd_device *device,
2377 struct dasd_ccw_req *cqr)
2378 {
2379 dasd_erp_fn_t erp_fn;
2380
2381 if (cqr->status == DASD_CQR_DONE)
2382 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
2383 else
2384 dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
2385 erp_fn = device->discipline->erp_postaction(cqr);
2386 erp_fn(cqr);
2387 }
2388
2389 /*
2390 * Fetch requests from the block device queue.
2391 */
2392 static void __dasd_process_request_queue(struct dasd_block *block)
2393 {
2394 struct request_queue *queue;
2395 struct request *req;
2396 struct dasd_ccw_req *cqr;
2397 struct dasd_device *basedev;
2398 unsigned long flags;
2399 queue = block->request_queue;
2400 basedev = block->base;
2401 /* No queue ? Then there is nothing to do. */
2402 if (queue == NULL)
2403 return;
2404
2405 /*
2406 * We requeue request from the block device queue to the ccw
2407 * queue only in two states. In state DASD_STATE_READY the
2408 * partition detection is done and we need to requeue requests
2409 * for that. State DASD_STATE_ONLINE is normal block device
2410 * operation.
2411 */
2412 if (basedev->state < DASD_STATE_READY) {
2413 while ((req = blk_fetch_request(block->request_queue)))
2414 __blk_end_request_all(req, -EIO);
2415 return;
2416 }
2417 /* Now we try to fetch requests from the request queue */
2418 while ((req = blk_peek_request(queue))) {
2419 if (basedev->features & DASD_FEATURE_READONLY &&
2420 rq_data_dir(req) == WRITE) {
2421 DBF_DEV_EVENT(DBF_ERR, basedev,
2422 "Rejecting write request %p",
2423 req);
2424 blk_start_request(req);
2425 __blk_end_request_all(req, -EIO);
2426 continue;
2427 }
2428 cqr = basedev->discipline->build_cp(basedev, block, req);
2429 if (IS_ERR(cqr)) {
2430 if (PTR_ERR(cqr) == -EBUSY)
2431 break; /* normal end condition */
2432 if (PTR_ERR(cqr) == -ENOMEM)
2433 break; /* terminate request queue loop */
2434 if (PTR_ERR(cqr) == -EAGAIN) {
2435 /*
2436 * The current request cannot be build right
2437 * now, we have to try later. If this request
2438 * is the head-of-queue we stop the device
2439 * for 1/2 second.
2440 */
2441 if (!list_empty(&block->ccw_queue))
2442 break;
2443 spin_lock_irqsave(
2444 get_ccwdev_lock(basedev->cdev), flags);
2445 dasd_device_set_stop_bits(basedev,
2446 DASD_STOPPED_PENDING);
2447 spin_unlock_irqrestore(
2448 get_ccwdev_lock(basedev->cdev), flags);
2449 dasd_block_set_timer(block, HZ/2);
2450 break;
2451 }
2452 DBF_DEV_EVENT(DBF_ERR, basedev,
2453 "CCW creation failed (rc=%ld) "
2454 "on request %p",
2455 PTR_ERR(cqr), req);
2456 blk_start_request(req);
2457 __blk_end_request_all(req, -EIO);
2458 continue;
2459 }
2460 /*
2461 * Note: callback is set to dasd_return_cqr_cb in
2462 * __dasd_block_start_head to cover erp requests as well
2463 */
2464 cqr->callback_data = (void *) req;
2465 cqr->status = DASD_CQR_FILLED;
2466 blk_start_request(req);
2467 list_add_tail(&cqr->blocklist, &block->ccw_queue);
2468 dasd_profile_start(block, cqr, req);
2469 }
2470 }
2471
2472 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
2473 {
2474 struct request *req;
2475 int status;
2476 int error = 0;
2477
2478 req = (struct request *) cqr->callback_data;
2479 dasd_profile_end(cqr->block, cqr, req);
2480 status = cqr->block->base->discipline->free_cp(cqr, req);
2481 if (status <= 0)
2482 error = status ? status : -EIO;
2483 __blk_end_request_all(req, error);
2484 }
2485
2486 /*
2487 * Process ccw request queue.
2488 */
2489 static void __dasd_process_block_ccw_queue(struct dasd_block *block,
2490 struct list_head *final_queue)
2491 {
2492 struct list_head *l, *n;
2493 struct dasd_ccw_req *cqr;
2494 dasd_erp_fn_t erp_fn;
2495 unsigned long flags;
2496 struct dasd_device *base = block->base;
2497
2498 restart:
2499 /* Process request with final status. */
2500 list_for_each_safe(l, n, &block->ccw_queue) {
2501 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2502 if (cqr->status != DASD_CQR_DONE &&
2503 cqr->status != DASD_CQR_FAILED &&
2504 cqr->status != DASD_CQR_NEED_ERP &&
2505 cqr->status != DASD_CQR_TERMINATED)
2506 continue;
2507
2508 if (cqr->status == DASD_CQR_TERMINATED) {
2509 base->discipline->handle_terminated_request(cqr);
2510 goto restart;
2511 }
2512
2513 /* Process requests that may be recovered */
2514 if (cqr->status == DASD_CQR_NEED_ERP) {
2515 erp_fn = base->discipline->erp_action(cqr);
2516 if (IS_ERR(erp_fn(cqr)))
2517 continue;
2518 goto restart;
2519 }
2520
2521 /* log sense for fatal error */
2522 if (cqr->status == DASD_CQR_FAILED) {
2523 dasd_log_sense(cqr, &cqr->irb);
2524 }
2525
2526 /* First of all call extended error reporting. */
2527 if (dasd_eer_enabled(base) &&
2528 cqr->status == DASD_CQR_FAILED) {
2529 dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
2530
2531 /* restart request */
2532 cqr->status = DASD_CQR_FILLED;
2533 cqr->retries = 255;
2534 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
2535 dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
2536 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
2537 flags);
2538 goto restart;
2539 }
2540
2541 /* Process finished ERP request. */
2542 if (cqr->refers) {
2543 __dasd_process_erp(base, cqr);
2544 goto restart;
2545 }
2546
2547 /* Rechain finished requests to final queue */
2548 cqr->endclk = get_clock();
2549 list_move_tail(&cqr->blocklist, final_queue);
2550 }
2551 }
2552
2553 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
2554 {
2555 dasd_schedule_block_bh(cqr->block);
2556 }
2557
2558 static void __dasd_block_start_head(struct dasd_block *block)
2559 {
2560 struct dasd_ccw_req *cqr;
2561
2562 if (list_empty(&block->ccw_queue))
2563 return;
2564 /* We allways begin with the first requests on the queue, as some
2565 * of previously started requests have to be enqueued on a
2566 * dasd_device again for error recovery.
2567 */
2568 list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
2569 if (cqr->status != DASD_CQR_FILLED)
2570 continue;
2571 if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) &&
2572 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2573 cqr->status = DASD_CQR_FAILED;
2574 cqr->intrc = -EPERM;
2575 dasd_schedule_block_bh(block);
2576 continue;
2577 }
2578 /* Non-temporary stop condition will trigger fail fast */
2579 if (block->base->stopped & ~DASD_STOPPED_PENDING &&
2580 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2581 (!dasd_eer_enabled(block->base))) {
2582 cqr->status = DASD_CQR_FAILED;
2583 dasd_schedule_block_bh(block);
2584 continue;
2585 }
2586 /* Don't try to start requests if device is stopped */
2587 if (block->base->stopped)
2588 return;
2589
2590 /* just a fail safe check, should not happen */
2591 if (!cqr->startdev)
2592 cqr->startdev = block->base;
2593
2594 /* make sure that the requests we submit find their way back */
2595 cqr->callback = dasd_return_cqr_cb;
2596
2597 dasd_add_request_tail(cqr);
2598 }
2599 }
2600
2601 /*
2602 * Central dasd_block layer routine. Takes requests from the generic
2603 * block layer request queue, creates ccw requests, enqueues them on
2604 * a dasd_device and processes ccw requests that have been returned.
2605 */
2606 static void dasd_block_tasklet(struct dasd_block *block)
2607 {
2608 struct list_head final_queue;
2609 struct list_head *l, *n;
2610 struct dasd_ccw_req *cqr;
2611
2612 atomic_set(&block->tasklet_scheduled, 0);
2613 INIT_LIST_HEAD(&final_queue);
2614 spin_lock(&block->queue_lock);
2615 /* Finish off requests on ccw queue */
2616 __dasd_process_block_ccw_queue(block, &final_queue);
2617 spin_unlock(&block->queue_lock);
2618 /* Now call the callback function of requests with final status */
2619 spin_lock_irq(&block->request_queue_lock);
2620 list_for_each_safe(l, n, &final_queue) {
2621 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2622 list_del_init(&cqr->blocklist);
2623 __dasd_cleanup_cqr(cqr);
2624 }
2625 spin_lock(&block->queue_lock);
2626 /* Get new request from the block device request queue */
2627 __dasd_process_request_queue(block);
2628 /* Now check if the head of the ccw queue needs to be started. */
2629 __dasd_block_start_head(block);
2630 spin_unlock(&block->queue_lock);
2631 spin_unlock_irq(&block->request_queue_lock);
2632 dasd_put_device(block->base);
2633 }
2634
2635 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
2636 {
2637 wake_up(&dasd_flush_wq);
2638 }
2639
2640 /*
2641 * Go through all request on the dasd_block request queue, cancel them
2642 * on the respective dasd_device, and return them to the generic
2643 * block layer.
2644 */
2645 static int dasd_flush_block_queue(struct dasd_block *block)
2646 {
2647 struct dasd_ccw_req *cqr, *n;
2648 int rc, i;
2649 struct list_head flush_queue;
2650
2651 INIT_LIST_HEAD(&flush_queue);
2652 spin_lock_bh(&block->queue_lock);
2653 rc = 0;
2654 restart:
2655 list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
2656 /* if this request currently owned by a dasd_device cancel it */
2657 if (cqr->status >= DASD_CQR_QUEUED)
2658 rc = dasd_cancel_req(cqr);
2659 if (rc < 0)
2660 break;
2661 /* Rechain request (including erp chain) so it won't be
2662 * touched by the dasd_block_tasklet anymore.
2663 * Replace the callback so we notice when the request
2664 * is returned from the dasd_device layer.
2665 */
2666 cqr->callback = _dasd_wake_block_flush_cb;
2667 for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
2668 list_move_tail(&cqr->blocklist, &flush_queue);
2669 if (i > 1)
2670 /* moved more than one request - need to restart */
2671 goto restart;
2672 }
2673 spin_unlock_bh(&block->queue_lock);
2674 /* Now call the callback function of flushed requests */
2675 restart_cb:
2676 list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
2677 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
2678 /* Process finished ERP request. */
2679 if (cqr->refers) {
2680 spin_lock_bh(&block->queue_lock);
2681 __dasd_process_erp(block->base, cqr);
2682 spin_unlock_bh(&block->queue_lock);
2683 /* restart list_for_xx loop since dasd_process_erp
2684 * might remove multiple elements */
2685 goto restart_cb;
2686 }
2687 /* call the callback function */
2688 spin_lock_irq(&block->request_queue_lock);
2689 cqr->endclk = get_clock();
2690 list_del_init(&cqr->blocklist);
2691 __dasd_cleanup_cqr(cqr);
2692 spin_unlock_irq(&block->request_queue_lock);
2693 }
2694 return rc;
2695 }
2696
2697 /*
2698 * Schedules a call to dasd_tasklet over the device tasklet.
2699 */
2700 void dasd_schedule_block_bh(struct dasd_block *block)
2701 {
2702 /* Protect against rescheduling. */
2703 if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
2704 return;
2705 /* life cycle of block is bound to it's base device */
2706 dasd_get_device(block->base);
2707 tasklet_hi_schedule(&block->tasklet);
2708 }
2709
2710
2711 /*
2712 * SECTION: external block device operations
2713 * (request queue handling, open, release, etc.)
2714 */
2715
2716 /*
2717 * Dasd request queue function. Called from ll_rw_blk.c
2718 */
2719 static void do_dasd_request(struct request_queue *queue)
2720 {
2721 struct dasd_block *block;
2722
2723 block = queue->queuedata;
2724 spin_lock(&block->queue_lock);
2725 /* Get new request from the block device request queue */
2726 __dasd_process_request_queue(block);
2727 /* Now check if the head of the ccw queue needs to be started. */
2728 __dasd_block_start_head(block);
2729 spin_unlock(&block->queue_lock);
2730 }
2731
2732 /*
2733 * Allocate and initialize request queue and default I/O scheduler.
2734 */
2735 static int dasd_alloc_queue(struct dasd_block *block)
2736 {
2737 int rc;
2738
2739 block->request_queue = blk_init_queue(do_dasd_request,
2740 &block->request_queue_lock);
2741 if (block->request_queue == NULL)
2742 return -ENOMEM;
2743
2744 block->request_queue->queuedata = block;
2745
2746 elevator_exit(block->request_queue->elevator);
2747 block->request_queue->elevator = NULL;
2748 rc = elevator_init(block->request_queue, "deadline");
2749 if (rc) {
2750 blk_cleanup_queue(block->request_queue);
2751 return rc;
2752 }
2753 return 0;
2754 }
2755
2756 /*
2757 * Allocate and initialize request queue.
2758 */
2759 static void dasd_setup_queue(struct dasd_block *block)
2760 {
2761 int max;
2762
2763 if (block->base->features & DASD_FEATURE_USERAW) {
2764 /*
2765 * the max_blocks value for raw_track access is 256
2766 * it is higher than the native ECKD value because we
2767 * only need one ccw per track
2768 * so the max_hw_sectors are
2769 * 2048 x 512B = 1024kB = 16 tracks
2770 */
2771 max = 2048;
2772 } else {
2773 max = block->base->discipline->max_blocks << block->s2b_shift;
2774 }
2775 blk_queue_logical_block_size(block->request_queue,
2776 block->bp_block);
2777 blk_queue_max_hw_sectors(block->request_queue, max);
2778 blk_queue_max_segments(block->request_queue, -1L);
2779 /* with page sized segments we can translate each segement into
2780 * one idaw/tidaw
2781 */
2782 blk_queue_max_segment_size(block->request_queue, PAGE_SIZE);
2783 blk_queue_segment_boundary(block->request_queue, PAGE_SIZE - 1);
2784 }
2785
2786 /*
2787 * Deactivate and free request queue.
2788 */
2789 static void dasd_free_queue(struct dasd_block *block)
2790 {
2791 if (block->request_queue) {
2792 blk_cleanup_queue(block->request_queue);
2793 block->request_queue = NULL;
2794 }
2795 }
2796
2797 /*
2798 * Flush request on the request queue.
2799 */
2800 static void dasd_flush_request_queue(struct dasd_block *block)
2801 {
2802 struct request *req;
2803
2804 if (!block->request_queue)
2805 return;
2806
2807 spin_lock_irq(&block->request_queue_lock);
2808 while ((req = blk_fetch_request(block->request_queue)))
2809 __blk_end_request_all(req, -EIO);
2810 spin_unlock_irq(&block->request_queue_lock);
2811 }
2812
2813 static int dasd_open(struct block_device *bdev, fmode_t mode)
2814 {
2815 struct dasd_device *base;
2816 int rc;
2817
2818 base = dasd_device_from_gendisk(bdev->bd_disk);
2819 if (!base)
2820 return -ENODEV;
2821
2822 atomic_inc(&base->block->open_count);
2823 if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
2824 rc = -ENODEV;
2825 goto unlock;
2826 }
2827
2828 if (!try_module_get(base->discipline->owner)) {
2829 rc = -EINVAL;
2830 goto unlock;
2831 }
2832
2833 if (dasd_probeonly) {
2834 dev_info(&base->cdev->dev,
2835 "Accessing the DASD failed because it is in "
2836 "probeonly mode\n");
2837 rc = -EPERM;
2838 goto out;
2839 }
2840
2841 if (base->state <= DASD_STATE_BASIC) {
2842 DBF_DEV_EVENT(DBF_ERR, base, " %s",
2843 " Cannot open unrecognized device");
2844 rc = -ENODEV;
2845 goto out;
2846 }
2847
2848 if ((mode & FMODE_WRITE) &&
2849 (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) ||
2850 (base->features & DASD_FEATURE_READONLY))) {
2851 rc = -EROFS;
2852 goto out;
2853 }
2854
2855 dasd_put_device(base);
2856 return 0;
2857
2858 out:
2859 module_put(base->discipline->owner);
2860 unlock:
2861 atomic_dec(&base->block->open_count);
2862 dasd_put_device(base);
2863 return rc;
2864 }
2865
2866 static int dasd_release(struct gendisk *disk, fmode_t mode)
2867 {
2868 struct dasd_device *base;
2869
2870 base = dasd_device_from_gendisk(disk);
2871 if (!base)
2872 return -ENODEV;
2873
2874 atomic_dec(&base->block->open_count);
2875 module_put(base->discipline->owner);
2876 dasd_put_device(base);
2877 return 0;
2878 }
2879
2880 /*
2881 * Return disk geometry.
2882 */
2883 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
2884 {
2885 struct dasd_device *base;
2886
2887 base = dasd_device_from_gendisk(bdev->bd_disk);
2888 if (!base)
2889 return -ENODEV;
2890
2891 if (!base->discipline ||
2892 !base->discipline->fill_geometry) {
2893 dasd_put_device(base);
2894 return -EINVAL;
2895 }
2896 base->discipline->fill_geometry(base->block, geo);
2897 geo->start = get_start_sect(bdev) >> base->block->s2b_shift;
2898 dasd_put_device(base);
2899 return 0;
2900 }
2901
2902 const struct block_device_operations
2903 dasd_device_operations = {
2904 .owner = THIS_MODULE,
2905 .open = dasd_open,
2906 .release = dasd_release,
2907 .ioctl = dasd_ioctl,
2908 .compat_ioctl = dasd_ioctl,
2909 .getgeo = dasd_getgeo,
2910 };
2911
2912 /*******************************************************************************
2913 * end of block device operations
2914 */
2915
2916 static void
2917 dasd_exit(void)
2918 {
2919 #ifdef CONFIG_PROC_FS
2920 dasd_proc_exit();
2921 #endif
2922 dasd_eer_exit();
2923 if (dasd_page_cache != NULL) {
2924 kmem_cache_destroy(dasd_page_cache);
2925 dasd_page_cache = NULL;
2926 }
2927 dasd_gendisk_exit();
2928 dasd_devmap_exit();
2929 if (dasd_debug_area != NULL) {
2930 debug_unregister(dasd_debug_area);
2931 dasd_debug_area = NULL;
2932 }
2933 dasd_statistics_removeroot();
2934 }
2935
2936 /*
2937 * SECTION: common functions for ccw_driver use
2938 */
2939
2940 /*
2941 * Is the device read-only?
2942 * Note that this function does not report the setting of the
2943 * readonly device attribute, but how it is configured in z/VM.
2944 */
2945 int dasd_device_is_ro(struct dasd_device *device)
2946 {
2947 struct ccw_dev_id dev_id;
2948 struct diag210 diag_data;
2949 int rc;
2950
2951 if (!MACHINE_IS_VM)
2952 return 0;
2953 ccw_device_get_id(device->cdev, &dev_id);
2954 memset(&diag_data, 0, sizeof(diag_data));
2955 diag_data.vrdcdvno = dev_id.devno;
2956 diag_data.vrdclen = sizeof(diag_data);
2957 rc = diag210(&diag_data);
2958 if (rc == 0 || rc == 2) {
2959 return diag_data.vrdcvfla & 0x80;
2960 } else {
2961 DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d",
2962 dev_id.devno, rc);
2963 return 0;
2964 }
2965 }
2966 EXPORT_SYMBOL_GPL(dasd_device_is_ro);
2967
2968 static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
2969 {
2970 struct ccw_device *cdev = data;
2971 int ret;
2972
2973 ret = ccw_device_set_online(cdev);
2974 if (ret)
2975 pr_warning("%s: Setting the DASD online failed with rc=%d\n",
2976 dev_name(&cdev->dev), ret);
2977 }
2978
2979 /*
2980 * Initial attempt at a probe function. this can be simplified once
2981 * the other detection code is gone.
2982 */
2983 int dasd_generic_probe(struct ccw_device *cdev,
2984 struct dasd_discipline *discipline)
2985 {
2986 int ret;
2987
2988 ret = dasd_add_sysfs_files(cdev);
2989 if (ret) {
2990 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s",
2991 "dasd_generic_probe: could not add "
2992 "sysfs entries");
2993 return ret;
2994 }
2995 cdev->handler = &dasd_int_handler;
2996
2997 /*
2998 * Automatically online either all dasd devices (dasd_autodetect)
2999 * or all devices specified with dasd= parameters during
3000 * initial probe.
3001 */
3002 if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
3003 (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
3004 async_schedule(dasd_generic_auto_online, cdev);
3005 return 0;
3006 }
3007
3008 /*
3009 * This will one day be called from a global not_oper handler.
3010 * It is also used by driver_unregister during module unload.
3011 */
3012 void dasd_generic_remove(struct ccw_device *cdev)
3013 {
3014 struct dasd_device *device;
3015 struct dasd_block *block;
3016
3017 cdev->handler = NULL;
3018
3019 dasd_remove_sysfs_files(cdev);
3020 device = dasd_device_from_cdev(cdev);
3021 if (IS_ERR(device))
3022 return;
3023 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3024 /* Already doing offline processing */
3025 dasd_put_device(device);
3026 return;
3027 }
3028 /*
3029 * This device is removed unconditionally. Set offline
3030 * flag to prevent dasd_open from opening it while it is
3031 * no quite down yet.
3032 */
3033 dasd_set_target_state(device, DASD_STATE_NEW);
3034 /* dasd_delete_device destroys the device reference. */
3035 block = device->block;
3036 dasd_delete_device(device);
3037 /*
3038 * life cycle of block is bound to device, so delete it after
3039 * device was safely removed
3040 */
3041 if (block)
3042 dasd_free_block(block);
3043 }
3044
3045 /*
3046 * Activate a device. This is called from dasd_{eckd,fba}_probe() when either
3047 * the device is detected for the first time and is supposed to be used
3048 * or the user has started activation through sysfs.
3049 */
3050 int dasd_generic_set_online(struct ccw_device *cdev,
3051 struct dasd_discipline *base_discipline)
3052 {
3053 struct dasd_discipline *discipline;
3054 struct dasd_device *device;
3055 int rc;
3056
3057 /* first online clears initial online feature flag */
3058 dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
3059 device = dasd_create_device(cdev);
3060 if (IS_ERR(device))
3061 return PTR_ERR(device);
3062
3063 discipline = base_discipline;
3064 if (device->features & DASD_FEATURE_USEDIAG) {
3065 if (!dasd_diag_discipline_pointer) {
3066 pr_warning("%s Setting the DASD online failed because "
3067 "of missing DIAG discipline\n",
3068 dev_name(&cdev->dev));
3069 dasd_delete_device(device);
3070 return -ENODEV;
3071 }
3072 discipline = dasd_diag_discipline_pointer;
3073 }
3074 if (!try_module_get(base_discipline->owner)) {
3075 dasd_delete_device(device);
3076 return -EINVAL;
3077 }
3078 if (!try_module_get(discipline->owner)) {
3079 module_put(base_discipline->owner);
3080 dasd_delete_device(device);
3081 return -EINVAL;
3082 }
3083 device->base_discipline = base_discipline;
3084 device->discipline = discipline;
3085
3086 /* check_device will allocate block device if necessary */
3087 rc = discipline->check_device(device);
3088 if (rc) {
3089 pr_warning("%s Setting the DASD online with discipline %s "
3090 "failed with rc=%i\n",
3091 dev_name(&cdev->dev), discipline->name, rc);
3092 module_put(discipline->owner);
3093 module_put(base_discipline->owner);
3094 dasd_delete_device(device);
3095 return rc;
3096 }
3097
3098 dasd_set_target_state(device, DASD_STATE_ONLINE);
3099 if (device->state <= DASD_STATE_KNOWN) {
3100 pr_warning("%s Setting the DASD online failed because of a "
3101 "missing discipline\n", dev_name(&cdev->dev));
3102 rc = -ENODEV;
3103 dasd_set_target_state(device, DASD_STATE_NEW);
3104 if (device->block)
3105 dasd_free_block(device->block);
3106 dasd_delete_device(device);
3107 } else
3108 pr_debug("dasd_generic device %s found\n",
3109 dev_name(&cdev->dev));
3110
3111 wait_event(dasd_init_waitq, _wait_for_device(device));
3112
3113 dasd_put_device(device);
3114 return rc;
3115 }
3116
3117 int dasd_generic_set_offline(struct ccw_device *cdev)
3118 {
3119 struct dasd_device *device;
3120 struct dasd_block *block;
3121 int max_count, open_count;
3122
3123 device = dasd_device_from_cdev(cdev);
3124 if (IS_ERR(device))
3125 return PTR_ERR(device);
3126 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3127 /* Already doing offline processing */
3128 dasd_put_device(device);
3129 return 0;
3130 }
3131 /*
3132 * We must make sure that this device is currently not in use.
3133 * The open_count is increased for every opener, that includes
3134 * the blkdev_get in dasd_scan_partitions. We are only interested
3135 * in the other openers.
3136 */
3137 if (device->block) {
3138 max_count = device->block->bdev ? 0 : -1;
3139 open_count = atomic_read(&device->block->open_count);
3140 if (open_count > max_count) {
3141 if (open_count > 0)
3142 pr_warning("%s: The DASD cannot be set offline "
3143 "with open count %i\n",
3144 dev_name(&cdev->dev), open_count);
3145 else
3146 pr_warning("%s: The DASD cannot be set offline "
3147 "while it is in use\n",
3148 dev_name(&cdev->dev));
3149 clear_bit(DASD_FLAG_OFFLINE, &device->flags);
3150 dasd_put_device(device);
3151 return -EBUSY;
3152 }
3153 }
3154 dasd_set_target_state(device, DASD_STATE_NEW);
3155 /* dasd_delete_device destroys the device reference. */
3156 block = device->block;
3157 dasd_delete_device(device);
3158 /*
3159 * life cycle of block is bound to device, so delete it after
3160 * device was safely removed
3161 */
3162 if (block)
3163 dasd_free_block(block);
3164 return 0;
3165 }
3166
3167 int dasd_generic_last_path_gone(struct dasd_device *device)
3168 {
3169 struct dasd_ccw_req *cqr;
3170
3171 dev_warn(&device->cdev->dev, "No operational channel path is left "
3172 "for the device\n");
3173 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone");
3174 /* First of all call extended error reporting. */
3175 dasd_eer_write(device, NULL, DASD_EER_NOPATH);
3176
3177 if (device->state < DASD_STATE_BASIC)
3178 return 0;
3179 /* Device is active. We want to keep it. */
3180 list_for_each_entry(cqr, &device->ccw_queue, devlist)
3181 if ((cqr->status == DASD_CQR_IN_IO) ||
3182 (cqr->status == DASD_CQR_CLEAR_PENDING)) {
3183 cqr->status = DASD_CQR_QUEUED;
3184 cqr->retries++;
3185 }
3186 dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT);
3187 dasd_device_clear_timer(device);
3188 dasd_schedule_device_bh(device);
3189 return 1;
3190 }
3191 EXPORT_SYMBOL_GPL(dasd_generic_last_path_gone);
3192
3193 int dasd_generic_path_operational(struct dasd_device *device)
3194 {
3195 dev_info(&device->cdev->dev, "A channel path to the device has become "
3196 "operational\n");
3197 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational");
3198 dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT);
3199 if (device->stopped & DASD_UNRESUMED_PM) {
3200 dasd_device_remove_stop_bits(device, DASD_UNRESUMED_PM);
3201 dasd_restore_device(device);
3202 return 1;
3203 }
3204 dasd_schedule_device_bh(device);
3205 if (device->block)
3206 dasd_schedule_block_bh(device->block);
3207 return 1;
3208 }
3209 EXPORT_SYMBOL_GPL(dasd_generic_path_operational);
3210
3211 int dasd_generic_notify(struct ccw_device *cdev, int event)
3212 {
3213 struct dasd_device *device;
3214 int ret;
3215
3216 device = dasd_device_from_cdev_locked(cdev);
3217 if (IS_ERR(device))
3218 return 0;
3219 ret = 0;
3220 switch (event) {
3221 case CIO_GONE:
3222 case CIO_BOXED:
3223 case CIO_NO_PATH:
3224 device->path_data.opm = 0;
3225 device->path_data.ppm = 0;
3226 device->path_data.npm = 0;
3227 ret = dasd_generic_last_path_gone(device);
3228 break;
3229 case CIO_OPER:
3230 ret = 1;
3231 if (device->path_data.opm)
3232 ret = dasd_generic_path_operational(device);
3233 break;
3234 }
3235 dasd_put_device(device);
3236 return ret;
3237 }
3238
3239 void dasd_generic_path_event(struct ccw_device *cdev, int *path_event)
3240 {
3241 int chp;
3242 __u8 oldopm, eventlpm;
3243 struct dasd_device *device;
3244
3245 device = dasd_device_from_cdev_locked(cdev);
3246 if (IS_ERR(device))
3247 return;
3248 for (chp = 0; chp < 8; chp++) {
3249 eventlpm = 0x80 >> chp;
3250 if (path_event[chp] & PE_PATH_GONE) {
3251 oldopm = device->path_data.opm;
3252 device->path_data.opm &= ~eventlpm;
3253 device->path_data.ppm &= ~eventlpm;
3254 device->path_data.npm &= ~eventlpm;
3255 if (oldopm && !device->path_data.opm)
3256 dasd_generic_last_path_gone(device);
3257 }
3258 if (path_event[chp] & PE_PATH_AVAILABLE) {
3259 device->path_data.opm &= ~eventlpm;
3260 device->path_data.ppm &= ~eventlpm;
3261 device->path_data.npm &= ~eventlpm;
3262 device->path_data.tbvpm |= eventlpm;
3263 dasd_schedule_device_bh(device);
3264 }
3265 }
3266 dasd_put_device(device);
3267 }
3268 EXPORT_SYMBOL_GPL(dasd_generic_path_event);
3269
3270 int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm)
3271 {
3272 if (!device->path_data.opm && lpm) {
3273 device->path_data.opm = lpm;
3274 dasd_generic_path_operational(device);
3275 } else
3276 device->path_data.opm |= lpm;
3277 return 0;
3278 }
3279 EXPORT_SYMBOL_GPL(dasd_generic_verify_path);
3280
3281
3282 int dasd_generic_pm_freeze(struct ccw_device *cdev)
3283 {
3284 struct dasd_ccw_req *cqr, *n;
3285 int rc;
3286 struct list_head freeze_queue;
3287 struct dasd_device *device = dasd_device_from_cdev(cdev);
3288
3289 if (IS_ERR(device))
3290 return PTR_ERR(device);
3291
3292 /* mark device as suspended */
3293 set_bit(DASD_FLAG_SUSPENDED, &device->flags);
3294
3295 if (device->discipline->freeze)
3296 rc = device->discipline->freeze(device);
3297
3298 /* disallow new I/O */
3299 dasd_device_set_stop_bits(device, DASD_STOPPED_PM);
3300 /* clear active requests */
3301 INIT_LIST_HEAD(&freeze_queue);
3302 spin_lock_irq(get_ccwdev_lock(cdev));
3303 rc = 0;
3304 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
3305 /* Check status and move request to flush_queue */
3306 if (cqr->status == DASD_CQR_IN_IO) {
3307 rc = device->discipline->term_IO(cqr);
3308 if (rc) {
3309 /* unable to terminate requeust */
3310 dev_err(&device->cdev->dev,
3311 "Unable to terminate request %p "
3312 "on suspend\n", cqr);
3313 spin_unlock_irq(get_ccwdev_lock(cdev));
3314 dasd_put_device(device);
3315 return rc;
3316 }
3317 }
3318 list_move_tail(&cqr->devlist, &freeze_queue);
3319 }
3320
3321 spin_unlock_irq(get_ccwdev_lock(cdev));
3322
3323 list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) {
3324 wait_event(dasd_flush_wq,
3325 (cqr->status != DASD_CQR_CLEAR_PENDING));
3326 if (cqr->status == DASD_CQR_CLEARED)
3327 cqr->status = DASD_CQR_QUEUED;
3328 }
3329 /* move freeze_queue to start of the ccw_queue */
3330 spin_lock_irq(get_ccwdev_lock(cdev));
3331 list_splice_tail(&freeze_queue, &device->ccw_queue);
3332 spin_unlock_irq(get_ccwdev_lock(cdev));
3333
3334 dasd_put_device(device);
3335 return rc;
3336 }
3337 EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze);
3338
3339 int dasd_generic_restore_device(struct ccw_device *cdev)
3340 {
3341 struct dasd_device *device = dasd_device_from_cdev(cdev);
3342 int rc = 0;
3343
3344 if (IS_ERR(device))
3345 return PTR_ERR(device);
3346
3347 /* allow new IO again */
3348 dasd_device_remove_stop_bits(device,
3349 (DASD_STOPPED_PM | DASD_UNRESUMED_PM));
3350
3351 dasd_schedule_device_bh(device);
3352
3353 /*
3354 * call discipline restore function
3355 * if device is stopped do nothing e.g. for disconnected devices
3356 */
3357 if (device->discipline->restore && !(device->stopped))
3358 rc = device->discipline->restore(device);
3359 if (rc || device->stopped)
3360 /*
3361 * if the resume failed for the DASD we put it in
3362 * an UNRESUMED stop state
3363 */
3364 device->stopped |= DASD_UNRESUMED_PM;
3365
3366 if (device->block)
3367 dasd_schedule_block_bh(device->block);
3368
3369 clear_bit(DASD_FLAG_SUSPENDED, &device->flags);
3370 dasd_put_device(device);
3371 return 0;
3372 }
3373 EXPORT_SYMBOL_GPL(dasd_generic_restore_device);
3374
3375 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
3376 void *rdc_buffer,
3377 int rdc_buffer_size,
3378 int magic)
3379 {
3380 struct dasd_ccw_req *cqr;
3381 struct ccw1 *ccw;
3382 unsigned long *idaw;
3383
3384 cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device);
3385
3386 if (IS_ERR(cqr)) {
3387 /* internal error 13 - Allocating the RDC request failed*/
3388 dev_err(&device->cdev->dev,
3389 "An error occurred in the DASD device driver, "
3390 "reason=%s\n", "13");
3391 return cqr;
3392 }
3393
3394 ccw = cqr->cpaddr;
3395 ccw->cmd_code = CCW_CMD_RDC;
3396 if (idal_is_needed(rdc_buffer, rdc_buffer_size)) {
3397 idaw = (unsigned long *) (cqr->data);
3398 ccw->cda = (__u32)(addr_t) idaw;
3399 ccw->flags = CCW_FLAG_IDA;
3400 idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size);
3401 } else {
3402 ccw->cda = (__u32)(addr_t) rdc_buffer;
3403 ccw->flags = 0;
3404 }
3405
3406 ccw->count = rdc_buffer_size;
3407 cqr->startdev = device;
3408 cqr->memdev = device;
3409 cqr->expires = 10*HZ;
3410 cqr->retries = 256;
3411 cqr->buildclk = get_clock();
3412 cqr->status = DASD_CQR_FILLED;
3413 return cqr;
3414 }
3415
3416
3417 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
3418 void *rdc_buffer, int rdc_buffer_size)
3419 {
3420 int ret;
3421 struct dasd_ccw_req *cqr;
3422
3423 cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size,
3424 magic);
3425 if (IS_ERR(cqr))
3426 return PTR_ERR(cqr);
3427
3428 ret = dasd_sleep_on(cqr);
3429 dasd_sfree_request(cqr, cqr->memdev);
3430 return ret;
3431 }
3432 EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
3433
3434 /*
3435 * In command mode and transport mode we need to look for sense
3436 * data in different places. The sense data itself is allways
3437 * an array of 32 bytes, so we can unify the sense data access
3438 * for both modes.
3439 */
3440 char *dasd_get_sense(struct irb *irb)
3441 {
3442 struct tsb *tsb = NULL;
3443 char *sense = NULL;
3444
3445 if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
3446 if (irb->scsw.tm.tcw)
3447 tsb = tcw_get_tsb((struct tcw *)(unsigned long)
3448 irb->scsw.tm.tcw);
3449 if (tsb && tsb->length == 64 && tsb->flags)
3450 switch (tsb->flags & 0x07) {
3451 case 1: /* tsa_iostat */
3452 sense = tsb->tsa.iostat.sense;
3453 break;
3454 case 2: /* tsa_ddpc */
3455 sense = tsb->tsa.ddpc.sense;
3456 break;
3457 default:
3458 /* currently we don't use interrogate data */
3459 break;
3460 }
3461 } else if (irb->esw.esw0.erw.cons) {
3462 sense = irb->ecw;
3463 }
3464 return sense;
3465 }
3466 EXPORT_SYMBOL_GPL(dasd_get_sense);
3467
3468 static int __init dasd_init(void)
3469 {
3470 int rc;
3471
3472 init_waitqueue_head(&dasd_init_waitq);
3473 init_waitqueue_head(&dasd_flush_wq);
3474 init_waitqueue_head(&generic_waitq);
3475
3476 /* register 'common' DASD debug area, used for all DBF_XXX calls */
3477 dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
3478 if (dasd_debug_area == NULL) {
3479 rc = -ENOMEM;
3480 goto failed;
3481 }
3482 debug_register_view(dasd_debug_area, &debug_sprintf_view);
3483 debug_set_level(dasd_debug_area, DBF_WARNING);
3484
3485 DBF_EVENT(DBF_EMERG, "%s", "debug area created");
3486
3487 dasd_diag_discipline_pointer = NULL;
3488
3489 dasd_statistics_createroot();
3490
3491 rc = dasd_devmap_init();
3492 if (rc)
3493 goto failed;
3494 rc = dasd_gendisk_init();
3495 if (rc)
3496 goto failed;
3497 rc = dasd_parse();
3498 if (rc)
3499 goto failed;
3500 rc = dasd_eer_init();
3501 if (rc)
3502 goto failed;
3503 #ifdef CONFIG_PROC_FS
3504 rc = dasd_proc_init();
3505 if (rc)
3506 goto failed;
3507 #endif
3508
3509 return 0;
3510 failed:
3511 pr_info("The DASD device driver could not be initialized\n");
3512 dasd_exit();
3513 return rc;
3514 }
3515
3516 module_init(dasd_init);
3517 module_exit(dasd_exit);
3518
3519 EXPORT_SYMBOL(dasd_debug_area);
3520 EXPORT_SYMBOL(dasd_diag_discipline_pointer);
3521
3522 EXPORT_SYMBOL(dasd_add_request_head);
3523 EXPORT_SYMBOL(dasd_add_request_tail);
3524 EXPORT_SYMBOL(dasd_cancel_req);
3525 EXPORT_SYMBOL(dasd_device_clear_timer);
3526 EXPORT_SYMBOL(dasd_block_clear_timer);
3527 EXPORT_SYMBOL(dasd_enable_device);
3528 EXPORT_SYMBOL(dasd_int_handler);
3529 EXPORT_SYMBOL(dasd_kfree_request);
3530 EXPORT_SYMBOL(dasd_kick_device);
3531 EXPORT_SYMBOL(dasd_kmalloc_request);
3532 EXPORT_SYMBOL(dasd_schedule_device_bh);
3533 EXPORT_SYMBOL(dasd_schedule_block_bh);
3534 EXPORT_SYMBOL(dasd_set_target_state);
3535 EXPORT_SYMBOL(dasd_device_set_timer);
3536 EXPORT_SYMBOL(dasd_block_set_timer);
3537 EXPORT_SYMBOL(dasd_sfree_request);
3538 EXPORT_SYMBOL(dasd_sleep_on);
3539 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
3540 EXPORT_SYMBOL(dasd_sleep_on_interruptible);
3541 EXPORT_SYMBOL(dasd_smalloc_request);
3542 EXPORT_SYMBOL(dasd_start_IO);
3543 EXPORT_SYMBOL(dasd_term_IO);
3544
3545 EXPORT_SYMBOL_GPL(dasd_generic_probe);
3546 EXPORT_SYMBOL_GPL(dasd_generic_remove);
3547 EXPORT_SYMBOL_GPL(dasd_generic_notify);
3548 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
3549 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
3550 EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
3551 EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
3552 EXPORT_SYMBOL_GPL(dasd_alloc_block);
3553 EXPORT_SYMBOL_GPL(dasd_free_block);
Linux with added FPC-III support