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dasd.c
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1 /*
2  * Author(s)......: Holger Smolinski <[email protected]>
3  * Horst Hummel <[email protected]>
4  * Carsten Otte <[email protected]>
5  * Martin Schwidefsky <[email protected]>
6  * Bugreports.to..: <[email protected]>
7  * Copyright IBM Corp. 1999, 2009
8  */
9 
10 #define KMSG_COMPONENT "dasd"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12 
13 #include <linux/kmod.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/ctype.h>
17 #include <linux/major.h>
18 #include <linux/slab.h>
19 #include <linux/hdreg.h>
20 #include <linux/async.h>
21 #include <linux/mutex.h>
22 #include <linux/debugfs.h>
23 #include <linux/seq_file.h>
24 #include <linux/vmalloc.h>
25 
26 #include <asm/ccwdev.h>
27 #include <asm/ebcdic.h>
28 #include <asm/idals.h>
29 #include <asm/itcw.h>
30 #include <asm/diag.h>
31 
32 /* This is ugly... */
33 #define PRINTK_HEADER "dasd:"
34 
35 #include "dasd_int.h"
36 /*
37  * SECTION: Constant definitions to be used within this file
38  */
39 #define DASD_CHANQ_MAX_SIZE 4
40 
41 #define DASD_SLEEPON_START_TAG (void *) 1
42 #define DASD_SLEEPON_END_TAG (void *) 2
43 
44 /*
45  * SECTION: exported variables of dasd.c
46  */
48 static struct dentry *dasd_debugfs_root_entry;
50 void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
51 
52 MODULE_AUTHOR("Holger Smolinski <[email protected]>");
53 MODULE_DESCRIPTION("Linux on S/390 DASD device driver,"
54  " Copyright IBM Corp. 2000");
56 MODULE_LICENSE("GPL");
57 
58 /*
59  * SECTION: prototypes for static functions of dasd.c
60  */
61 static int dasd_alloc_queue(struct dasd_block *);
62 static void dasd_setup_queue(struct dasd_block *);
63 static void dasd_free_queue(struct dasd_block *);
64 static void dasd_flush_request_queue(struct dasd_block *);
65 static int dasd_flush_block_queue(struct dasd_block *);
66 static void dasd_device_tasklet(struct dasd_device *);
67 static void dasd_block_tasklet(struct dasd_block *);
68 static void do_kick_device(struct work_struct *);
69 static void do_restore_device(struct work_struct *);
70 static void do_reload_device(struct work_struct *);
71 static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
72 static void dasd_device_timeout(unsigned long);
73 static void dasd_block_timeout(unsigned long);
74 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
75 static void dasd_profile_init(struct dasd_profile *, struct dentry *);
76 static void dasd_profile_exit(struct dasd_profile *);
77 
78 /*
79  * SECTION: Operations on the device structure.
80  */
81 static wait_queue_head_t dasd_init_waitq;
82 static wait_queue_head_t dasd_flush_wq;
83 static wait_queue_head_t generic_waitq;
84 static wait_queue_head_t shutdown_waitq;
85 
86 /*
87  * Allocate memory for a new device structure.
88  */
90 {
91  struct dasd_device *device;
92 
93  device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
94  if (!device)
95  return ERR_PTR(-ENOMEM);
96 
97  /* Get two pages for normal block device operations. */
98  device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
99  if (!device->ccw_mem) {
100  kfree(device);
101  return ERR_PTR(-ENOMEM);
102  }
103  /* Get one page for error recovery. */
104  device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
105  if (!device->erp_mem) {
106  free_pages((unsigned long) device->ccw_mem, 1);
107  kfree(device);
108  return ERR_PTR(-ENOMEM);
109  }
110 
111  dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
112  dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
113  spin_lock_init(&device->mem_lock);
114  atomic_set(&device->tasklet_scheduled, 0);
115  tasklet_init(&device->tasklet,
116  (void (*)(unsigned long)) dasd_device_tasklet,
117  (unsigned long) device);
118  INIT_LIST_HEAD(&device->ccw_queue);
119  init_timer(&device->timer);
120  device->timer.function = dasd_device_timeout;
121  device->timer.data = (unsigned long) device;
122  INIT_WORK(&device->kick_work, do_kick_device);
123  INIT_WORK(&device->restore_device, do_restore_device);
124  INIT_WORK(&device->reload_device, do_reload_device);
125  device->state = DASD_STATE_NEW;
126  device->target = DASD_STATE_NEW;
127  mutex_init(&device->state_mutex);
128  spin_lock_init(&device->profile.lock);
129  return device;
130 }
131 
132 /*
133  * Free memory of a device structure.
134  */
136 {
137  kfree(device->private);
138  free_page((unsigned long) device->erp_mem);
139  free_pages((unsigned long) device->ccw_mem, 1);
140  kfree(device);
141 }
142 
143 /*
144  * Allocate memory for a new device structure.
145  */
147 {
148  struct dasd_block *block;
149 
150  block = kzalloc(sizeof(*block), GFP_ATOMIC);
151  if (!block)
152  return ERR_PTR(-ENOMEM);
153  /* open_count = 0 means device online but not in use */
154  atomic_set(&block->open_count, -1);
155 
157  atomic_set(&block->tasklet_scheduled, 0);
158  tasklet_init(&block->tasklet,
159  (void (*)(unsigned long)) dasd_block_tasklet,
160  (unsigned long) block);
161  INIT_LIST_HEAD(&block->ccw_queue);
162  spin_lock_init(&block->queue_lock);
163  init_timer(&block->timer);
164  block->timer.function = dasd_block_timeout;
165  block->timer.data = (unsigned long) block;
166  spin_lock_init(&block->profile.lock);
167 
168  return block;
169 }
170 
171 /*
172  * Free memory of a device structure.
173  */
175 {
176  kfree(block);
177 }
178 
179 /*
180  * Make a new device known to the system.
181  */
182 static int dasd_state_new_to_known(struct dasd_device *device)
183 {
184  int rc;
185 
186  /*
187  * As long as the device is not in state DASD_STATE_NEW we want to
188  * keep the reference count > 0.
189  */
190  dasd_get_device(device);
191 
192  if (device->block) {
193  rc = dasd_alloc_queue(device->block);
194  if (rc) {
195  dasd_put_device(device);
196  return rc;
197  }
198  }
199  device->state = DASD_STATE_KNOWN;
200  return 0;
201 }
202 
203 /*
204  * Let the system forget about a device.
205  */
206 static int dasd_state_known_to_new(struct dasd_device *device)
207 {
208  /* Disable extended error reporting for this device. */
209  dasd_eer_disable(device);
210  /* Forget the discipline information. */
211  if (device->discipline) {
212  if (device->discipline->uncheck_device)
213  device->discipline->uncheck_device(device);
214  module_put(device->discipline->owner);
215  }
216  device->discipline = NULL;
217  if (device->base_discipline)
218  module_put(device->base_discipline->owner);
219  device->base_discipline = NULL;
220  device->state = DASD_STATE_NEW;
221 
222  if (device->block)
223  dasd_free_queue(device->block);
224 
225  /* Give up reference we took in dasd_state_new_to_known. */
226  dasd_put_device(device);
227  return 0;
228 }
229 
230 static struct dentry *dasd_debugfs_setup(const char *name,
231  struct dentry *base_dentry)
232 {
233  struct dentry *pde;
234 
235  if (!base_dentry)
236  return NULL;
237  pde = debugfs_create_dir(name, base_dentry);
238  if (!pde || IS_ERR(pde))
239  return NULL;
240  return pde;
241 }
242 
243 /*
244  * Request the irq line for the device.
245  */
246 static int dasd_state_known_to_basic(struct dasd_device *device)
247 {
248  struct dasd_block *block = device->block;
249  int rc;
250 
251  /* Allocate and register gendisk structure. */
252  if (block) {
253  rc = dasd_gendisk_alloc(block);
254  if (rc)
255  return rc;
256  block->debugfs_dentry =
257  dasd_debugfs_setup(block->gdp->disk_name,
258  dasd_debugfs_root_entry);
259  dasd_profile_init(&block->profile, block->debugfs_dentry);
261  dasd_profile_on(&device->block->profile);
262  }
263  device->debugfs_dentry =
264  dasd_debugfs_setup(dev_name(&device->cdev->dev),
265  dasd_debugfs_root_entry);
266  dasd_profile_init(&device->profile, device->debugfs_dentry);
267 
268  /* register 'device' debug area, used for all DBF_DEV_XXX calls */
269  device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
270  8 * sizeof(long));
273  DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
274 
275  device->state = DASD_STATE_BASIC;
276  return 0;
277 }
278 
279 /*
280  * Release the irq line for the device. Terminate any running i/o.
281  */
282 static int dasd_state_basic_to_known(struct dasd_device *device)
283 {
284  int rc;
285  if (device->block) {
286  dasd_profile_exit(&device->block->profile);
287  if (device->block->debugfs_dentry)
288  debugfs_remove(device->block->debugfs_dentry);
289  dasd_gendisk_free(device->block);
290  dasd_block_clear_timer(device->block);
291  }
292  rc = dasd_flush_device_queue(device);
293  if (rc)
294  return rc;
295  dasd_device_clear_timer(device);
296  dasd_profile_exit(&device->profile);
297  if (device->debugfs_dentry)
299 
300  DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
301  if (device->debug_area != NULL) {
302  debug_unregister(device->debug_area);
303  device->debug_area = NULL;
304  }
305  device->state = DASD_STATE_KNOWN;
306  return 0;
307 }
308 
309 /*
310  * Do the initial analysis. The do_analysis function may return
311  * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
312  * until the discipline decides to continue the startup sequence
313  * by calling the function dasd_change_state. The eckd disciplines
314  * uses this to start a ccw that detects the format. The completion
315  * interrupt for this detection ccw uses the kernel event daemon to
316  * trigger the call to dasd_change_state. All this is done in the
317  * discipline code, see dasd_eckd.c.
318  * After the analysis ccw is done (do_analysis returned 0) the block
319  * device is setup.
320  * In case the analysis returns an error, the device setup is stopped
321  * (a fake disk was already added to allow formatting).
322  */
323 static int dasd_state_basic_to_ready(struct dasd_device *device)
324 {
325  int rc;
326  struct dasd_block *block;
327 
328  rc = 0;
329  block = device->block;
330  /* make disk known with correct capacity */
331  if (block) {
332  if (block->base->discipline->do_analysis != NULL)
333  rc = block->base->discipline->do_analysis(block);
334  if (rc) {
335  if (rc != -EAGAIN)
336  device->state = DASD_STATE_UNFMT;
337  return rc;
338  }
339  dasd_setup_queue(block);
340  set_capacity(block->gdp,
341  block->blocks << block->s2b_shift);
342  device->state = DASD_STATE_READY;
343  rc = dasd_scan_partitions(block);
344  if (rc)
345  device->state = DASD_STATE_BASIC;
346  } else {
347  device->state = DASD_STATE_READY;
348  }
349  return rc;
350 }
351 
352 /*
353  * Remove device from block device layer. Destroy dirty buffers.
354  * Forget format information. Check if the target level is basic
355  * and if it is create fake disk for formatting.
356  */
357 static int dasd_state_ready_to_basic(struct dasd_device *device)
358 {
359  int rc;
360 
361  device->state = DASD_STATE_BASIC;
362  if (device->block) {
363  struct dasd_block *block = device->block;
364  rc = dasd_flush_block_queue(block);
365  if (rc) {
366  device->state = DASD_STATE_READY;
367  return rc;
368  }
369  dasd_flush_request_queue(block);
371  block->blocks = 0;
372  block->bp_block = 0;
373  block->s2b_shift = 0;
374  }
375  return 0;
376 }
377 
378 /*
379  * Back to basic.
380  */
381 static int dasd_state_unfmt_to_basic(struct dasd_device *device)
382 {
383  device->state = DASD_STATE_BASIC;
384  return 0;
385 }
386 
387 /*
388  * Make the device online and schedule the bottom half to start
389  * the requeueing of requests from the linux request queue to the
390  * ccw queue.
391  */
392 static int
393 dasd_state_ready_to_online(struct dasd_device * device)
394 {
395  int rc;
396  struct gendisk *disk;
397  struct disk_part_iter piter;
398  struct hd_struct *part;
399 
400  if (device->discipline->ready_to_online) {
401  rc = device->discipline->ready_to_online(device);
402  if (rc)
403  return rc;
404  }
405  device->state = DASD_STATE_ONLINE;
406  if (device->block) {
407  dasd_schedule_block_bh(device->block);
408  if ((device->features & DASD_FEATURE_USERAW)) {
409  disk = device->block->gdp;
410  kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
411  return 0;
412  }
413  disk = device->block->bdev->bd_disk;
414  disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
415  while ((part = disk_part_iter_next(&piter)))
416  kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
417  disk_part_iter_exit(&piter);
418  }
419  return 0;
420 }
421 
422 /*
423  * Stop the requeueing of requests again.
424  */
425 static int dasd_state_online_to_ready(struct dasd_device *device)
426 {
427  int rc;
428  struct gendisk *disk;
429  struct disk_part_iter piter;
430  struct hd_struct *part;
431 
432  if (device->discipline->online_to_ready) {
433  rc = device->discipline->online_to_ready(device);
434  if (rc)
435  return rc;
436  }
437  device->state = DASD_STATE_READY;
438  if (device->block && !(device->features & DASD_FEATURE_USERAW)) {
439  disk = device->block->bdev->bd_disk;
440  disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
441  while ((part = disk_part_iter_next(&piter)))
442  kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
443  disk_part_iter_exit(&piter);
444  }
445  return 0;
446 }
447 
448 /*
449  * Device startup state changes.
450  */
451 static int dasd_increase_state(struct dasd_device *device)
452 {
453  int rc;
454 
455  rc = 0;
456  if (device->state == DASD_STATE_NEW &&
457  device->target >= DASD_STATE_KNOWN)
458  rc = dasd_state_new_to_known(device);
459 
460  if (!rc &&
461  device->state == DASD_STATE_KNOWN &&
462  device->target >= DASD_STATE_BASIC)
463  rc = dasd_state_known_to_basic(device);
464 
465  if (!rc &&
466  device->state == DASD_STATE_BASIC &&
467  device->target >= DASD_STATE_READY)
468  rc = dasd_state_basic_to_ready(device);
469 
470  if (!rc &&
471  device->state == DASD_STATE_UNFMT &&
472  device->target > DASD_STATE_UNFMT)
473  rc = -EPERM;
474 
475  if (!rc &&
476  device->state == DASD_STATE_READY &&
477  device->target >= DASD_STATE_ONLINE)
478  rc = dasd_state_ready_to_online(device);
479 
480  return rc;
481 }
482 
483 /*
484  * Device shutdown state changes.
485  */
486 static int dasd_decrease_state(struct dasd_device *device)
487 {
488  int rc;
489 
490  rc = 0;
491  if (device->state == DASD_STATE_ONLINE &&
492  device->target <= DASD_STATE_READY)
493  rc = dasd_state_online_to_ready(device);
494 
495  if (!rc &&
496  device->state == DASD_STATE_READY &&
497  device->target <= DASD_STATE_BASIC)
498  rc = dasd_state_ready_to_basic(device);
499 
500  if (!rc &&
501  device->state == DASD_STATE_UNFMT &&
502  device->target <= DASD_STATE_BASIC)
503  rc = dasd_state_unfmt_to_basic(device);
504 
505  if (!rc &&
506  device->state == DASD_STATE_BASIC &&
507  device->target <= DASD_STATE_KNOWN)
508  rc = dasd_state_basic_to_known(device);
509 
510  if (!rc &&
511  device->state == DASD_STATE_KNOWN &&
512  device->target <= DASD_STATE_NEW)
513  rc = dasd_state_known_to_new(device);
514 
515  return rc;
516 }
517 
518 /*
519  * This is the main startup/shutdown routine.
520  */
521 static void dasd_change_state(struct dasd_device *device)
522 {
523  int rc;
524 
525  if (device->state == device->target)
526  /* Already where we want to go today... */
527  return;
528  if (device->state < device->target)
529  rc = dasd_increase_state(device);
530  else
531  rc = dasd_decrease_state(device);
532  if (rc == -EAGAIN)
533  return;
534  if (rc)
535  device->target = device->state;
536 
537  /* let user-space know that the device status changed */
538  kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
539 
540  if (device->state == device->target)
541  wake_up(&dasd_init_waitq);
542 }
543 
544 /*
545  * Kick starter for devices that did not complete the startup/shutdown
546  * procedure or were sleeping because of a pending state.
547  * dasd_kick_device will schedule a call do do_kick_device to the kernel
548  * event daemon.
549  */
550 static void do_kick_device(struct work_struct *work)
551 {
552  struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
553  mutex_lock(&device->state_mutex);
554  dasd_change_state(device);
555  mutex_unlock(&device->state_mutex);
556  dasd_schedule_device_bh(device);
557  dasd_put_device(device);
558 }
559 
560 void dasd_kick_device(struct dasd_device *device)
561 {
562  dasd_get_device(device);
563  /* queue call to dasd_kick_device to the kernel event daemon. */
564  schedule_work(&device->kick_work);
565 }
566 
567 /*
568  * dasd_reload_device will schedule a call do do_reload_device to the kernel
569  * event daemon.
570  */
571 static void do_reload_device(struct work_struct *work)
572 {
573  struct dasd_device *device = container_of(work, struct dasd_device,
574  reload_device);
575  device->discipline->reload(device);
576  dasd_put_device(device);
577 }
578 
579 void dasd_reload_device(struct dasd_device *device)
580 {
581  dasd_get_device(device);
582  /* queue call to dasd_reload_device to the kernel event daemon. */
583  schedule_work(&device->reload_device);
584 }
586 
587 /*
588  * dasd_restore_device will schedule a call do do_restore_device to the kernel
589  * event daemon.
590  */
591 static void do_restore_device(struct work_struct *work)
592 {
593  struct dasd_device *device = container_of(work, struct dasd_device,
595  device->cdev->drv->restore(device->cdev);
596  dasd_put_device(device);
597 }
598 
599 void dasd_restore_device(struct dasd_device *device)
600 {
601  dasd_get_device(device);
602  /* queue call to dasd_restore_device to the kernel event daemon. */
603  schedule_work(&device->restore_device);
604 }
605 
606 /*
607  * Set the target state for a device and starts the state change.
608  */
609 void dasd_set_target_state(struct dasd_device *device, int target)
610 {
611  dasd_get_device(device);
612  mutex_lock(&device->state_mutex);
613  /* If we are in probeonly mode stop at DASD_STATE_READY. */
614  if (dasd_probeonly && target > DASD_STATE_READY)
615  target = DASD_STATE_READY;
616  if (device->target != target) {
617  if (device->state == target)
618  wake_up(&dasd_init_waitq);
619  device->target = target;
620  }
621  if (device->state != device->target)
622  dasd_change_state(device);
623  mutex_unlock(&device->state_mutex);
624  dasd_put_device(device);
625 }
626 
627 /*
628  * Enable devices with device numbers in [from..to].
629  */
630 static inline int _wait_for_device(struct dasd_device *device)
631 {
632  return (device->state == device->target);
633 }
634 
635 void dasd_enable_device(struct dasd_device *device)
636 {
638  if (device->state <= DASD_STATE_KNOWN)
639  /* No discipline for device found. */
641  /* Now wait for the devices to come up. */
642  wait_event(dasd_init_waitq, _wait_for_device(device));
643 
644  dasd_reload_device(device);
645  if (device->discipline->kick_validate)
646  device->discipline->kick_validate(device);
647 }
648 
649 /*
650  * SECTION: device operation (interrupt handler, start i/o, term i/o ...)
651  */
652 
654 
655 #ifdef CONFIG_DASD_PROFILE
657 static struct dentry *dasd_global_profile_dentry;
658 static struct dentry *dasd_debugfs_global_entry;
659 
660 /*
661  * Add profiling information for cqr before execution.
662  */
663 static void dasd_profile_start(struct dasd_block *block,
664  struct dasd_ccw_req *cqr,
665  struct request *req)
666 {
667  struct list_head *l;
668  unsigned int counter;
669  struct dasd_device *device;
670 
671  /* count the length of the chanq for statistics */
672  counter = 0;
673  if (dasd_global_profile_level || block->profile.data)
674  list_for_each(l, &block->ccw_queue)
675  if (++counter >= 31)
676  break;
677 
678  if (dasd_global_profile_level) {
679  dasd_global_profile_data.dasd_io_nr_req[counter]++;
680  if (rq_data_dir(req) == READ)
681  dasd_global_profile_data.dasd_read_nr_req[counter]++;
682  }
683 
684  spin_lock(&block->profile.lock);
685  if (block->profile.data)
686  block->profile.data->dasd_io_nr_req[counter]++;
687  if (rq_data_dir(req) == READ)
688  block->profile.data->dasd_read_nr_req[counter]++;
689  spin_unlock(&block->profile.lock);
690 
691  /*
692  * We count the request for the start device, even though it may run on
693  * some other device due to error recovery. This way we make sure that
694  * we count each request only once.
695  */
696  device = cqr->startdev;
697  if (device->profile.data) {
698  counter = 1; /* request is not yet queued on the start device */
699  list_for_each(l, &device->ccw_queue)
700  if (++counter >= 31)
701  break;
702  }
703  spin_lock(&device->profile.lock);
704  if (device->profile.data) {
705  device->profile.data->dasd_io_nr_req[counter]++;
706  if (rq_data_dir(req) == READ)
707  device->profile.data->dasd_read_nr_req[counter]++;
708  }
709  spin_unlock(&device->profile.lock);
710 }
711 
712 /*
713  * Add profiling information for cqr after execution.
714  */
715 
716 #define dasd_profile_counter(value, index) \
717 { \
718  for (index = 0; index < 31 && value >> (2+index); index++) \
719  ; \
720 }
721 
722 static void dasd_profile_end_add_data(struct dasd_profile_info *data,
723  int is_alias,
724  int is_tpm,
725  int is_read,
726  long sectors,
727  int sectors_ind,
728  int tottime_ind,
729  int tottimeps_ind,
730  int strtime_ind,
731  int irqtime_ind,
732  int irqtimeps_ind,
733  int endtime_ind)
734 {
735  /* in case of an overflow, reset the whole profile */
736  if (data->dasd_io_reqs == UINT_MAX) {
737  memset(data, 0, sizeof(*data));
738  getnstimeofday(&data->starttod);
739  }
740  data->dasd_io_reqs++;
741  data->dasd_io_sects += sectors;
742  if (is_alias)
743  data->dasd_io_alias++;
744  if (is_tpm)
745  data->dasd_io_tpm++;
746 
747  data->dasd_io_secs[sectors_ind]++;
748  data->dasd_io_times[tottime_ind]++;
749  data->dasd_io_timps[tottimeps_ind]++;
750  data->dasd_io_time1[strtime_ind]++;
751  data->dasd_io_time2[irqtime_ind]++;
752  data->dasd_io_time2ps[irqtimeps_ind]++;
753  data->dasd_io_time3[endtime_ind]++;
754 
755  if (is_read) {
756  data->dasd_read_reqs++;
757  data->dasd_read_sects += sectors;
758  if (is_alias)
759  data->dasd_read_alias++;
760  if (is_tpm)
761  data->dasd_read_tpm++;
762  data->dasd_read_secs[sectors_ind]++;
763  data->dasd_read_times[tottime_ind]++;
764  data->dasd_read_time1[strtime_ind]++;
765  data->dasd_read_time2[irqtime_ind]++;
766  data->dasd_read_time3[endtime_ind]++;
767  }
768 }
769 
770 static void dasd_profile_end(struct dasd_block *block,
771  struct dasd_ccw_req *cqr,
772  struct request *req)
773 {
774  long strtime, irqtime, endtime, tottime; /* in microseconds */
775  long tottimeps, sectors;
776  struct dasd_device *device;
777  int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind;
778  int irqtime_ind, irqtimeps_ind, endtime_ind;
779 
780  device = cqr->startdev;
781  if (!(dasd_global_profile_level ||
782  block->profile.data ||
783  device->profile.data))
784  return;
785 
786  sectors = blk_rq_sectors(req);
787  if (!cqr->buildclk || !cqr->startclk ||
788  !cqr->stopclk || !cqr->endclk ||
789  !sectors)
790  return;
791 
792  strtime = ((cqr->startclk - cqr->buildclk) >> 12);
793  irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
794  endtime = ((cqr->endclk - cqr->stopclk) >> 12);
795  tottime = ((cqr->endclk - cqr->buildclk) >> 12);
796  tottimeps = tottime / sectors;
797 
798  dasd_profile_counter(sectors, sectors_ind);
799  dasd_profile_counter(tottime, tottime_ind);
800  dasd_profile_counter(tottimeps, tottimeps_ind);
801  dasd_profile_counter(strtime, strtime_ind);
802  dasd_profile_counter(irqtime, irqtime_ind);
803  dasd_profile_counter(irqtime / sectors, irqtimeps_ind);
804  dasd_profile_counter(endtime, endtime_ind);
805 
806  if (dasd_global_profile_level) {
807  dasd_profile_end_add_data(&dasd_global_profile_data,
808  cqr->startdev != block->base,
809  cqr->cpmode == 1,
810  rq_data_dir(req) == READ,
811  sectors, sectors_ind, tottime_ind,
812  tottimeps_ind, strtime_ind,
813  irqtime_ind, irqtimeps_ind,
814  endtime_ind);
815  }
816 
817  spin_lock(&block->profile.lock);
818  if (block->profile.data)
819  dasd_profile_end_add_data(block->profile.data,
820  cqr->startdev != block->base,
821  cqr->cpmode == 1,
822  rq_data_dir(req) == READ,
823  sectors, sectors_ind, tottime_ind,
824  tottimeps_ind, strtime_ind,
825  irqtime_ind, irqtimeps_ind,
826  endtime_ind);
827  spin_unlock(&block->profile.lock);
828 
829  spin_lock(&device->profile.lock);
830  if (device->profile.data)
831  dasd_profile_end_add_data(device->profile.data,
832  cqr->startdev != block->base,
833  cqr->cpmode == 1,
834  rq_data_dir(req) == READ,
835  sectors, sectors_ind, tottime_ind,
836  tottimeps_ind, strtime_ind,
837  irqtime_ind, irqtimeps_ind,
838  endtime_ind);
839  spin_unlock(&device->profile.lock);
840 }
841 
843 {
844  struct dasd_profile_info *data;
845 
846  spin_lock_bh(&profile->lock);
847  data = profile->data;
848  if (!data) {
849  spin_unlock_bh(&profile->lock);
850  return;
851  }
852  memset(data, 0, sizeof(*data));
853  getnstimeofday(&data->starttod);
854  spin_unlock_bh(&profile->lock);
855 }
856 
857 void dasd_global_profile_reset(void)
858 {
859  memset(&dasd_global_profile_data, 0, sizeof(dasd_global_profile_data));
861 }
862 
863 int dasd_profile_on(struct dasd_profile *profile)
864 {
865  struct dasd_profile_info *data;
866 
867  data = kzalloc(sizeof(*data), GFP_KERNEL);
868  if (!data)
869  return -ENOMEM;
870  spin_lock_bh(&profile->lock);
871  if (profile->data) {
872  spin_unlock_bh(&profile->lock);
873  kfree(data);
874  return 0;
875  }
876  getnstimeofday(&data->starttod);
877  profile->data = data;
878  spin_unlock_bh(&profile->lock);
879  return 0;
880 }
881 
882 void dasd_profile_off(struct dasd_profile *profile)
883 {
884  spin_lock_bh(&profile->lock);
885  kfree(profile->data);
886  profile->data = NULL;
887  spin_unlock_bh(&profile->lock);
888 }
889 
890 char *dasd_get_user_string(const char __user *user_buf, size_t user_len)
891 {
892  char *buffer;
893 
894  buffer = vmalloc(user_len + 1);
895  if (buffer == NULL)
896  return ERR_PTR(-ENOMEM);
897  if (copy_from_user(buffer, user_buf, user_len) != 0) {
898  vfree(buffer);
899  return ERR_PTR(-EFAULT);
900  }
901  /* got the string, now strip linefeed. */
902  if (buffer[user_len - 1] == '\n')
903  buffer[user_len - 1] = 0;
904  else
905  buffer[user_len] = 0;
906  return buffer;
907 }
908 
909 static ssize_t dasd_stats_write(struct file *file,
910  const char __user *user_buf,
911  size_t user_len, loff_t *pos)
912 {
913  char *buffer, *str;
914  int rc;
915  struct seq_file *m = (struct seq_file *)file->private_data;
916  struct dasd_profile *prof = m->private;
917 
918  if (user_len > 65536)
919  user_len = 65536;
920  buffer = dasd_get_user_string(user_buf, user_len);
921  if (IS_ERR(buffer))
922  return PTR_ERR(buffer);
923 
924  str = skip_spaces(buffer);
925  rc = user_len;
926  if (strncmp(str, "reset", 5) == 0) {
927  dasd_profile_reset(prof);
928  } else if (strncmp(str, "on", 2) == 0) {
929  rc = dasd_profile_on(prof);
930  if (!rc)
931  rc = user_len;
932  } else if (strncmp(str, "off", 3) == 0) {
933  dasd_profile_off(prof);
934  } else
935  rc = -EINVAL;
936  vfree(buffer);
937  return rc;
938 }
939 
940 static void dasd_stats_array(struct seq_file *m, unsigned int *array)
941 {
942  int i;
943 
944  for (i = 0; i < 32; i++)
945  seq_printf(m, "%u ", array[i]);
946  seq_putc(m, '\n');
947 }
948 
949 static void dasd_stats_seq_print(struct seq_file *m,
950  struct dasd_profile_info *data)
951 {
952  seq_printf(m, "start_time %ld.%09ld\n",
953  data->starttod.tv_sec, data->starttod.tv_nsec);
954  seq_printf(m, "total_requests %u\n", data->dasd_io_reqs);
955  seq_printf(m, "total_sectors %u\n", data->dasd_io_sects);
956  seq_printf(m, "total_pav %u\n", data->dasd_io_alias);
957  seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm);
958  seq_printf(m, "histogram_sectors ");
959  dasd_stats_array(m, data->dasd_io_secs);
960  seq_printf(m, "histogram_io_times ");
961  dasd_stats_array(m, data->dasd_io_times);
962  seq_printf(m, "histogram_io_times_weighted ");
963  dasd_stats_array(m, data->dasd_io_timps);
964  seq_printf(m, "histogram_time_build_to_ssch ");
965  dasd_stats_array(m, data->dasd_io_time1);
966  seq_printf(m, "histogram_time_ssch_to_irq ");
967  dasd_stats_array(m, data->dasd_io_time2);
968  seq_printf(m, "histogram_time_ssch_to_irq_weighted ");
969  dasd_stats_array(m, data->dasd_io_time2ps);
970  seq_printf(m, "histogram_time_irq_to_end ");
971  dasd_stats_array(m, data->dasd_io_time3);
972  seq_printf(m, "histogram_ccw_queue_length ");
973  dasd_stats_array(m, data->dasd_io_nr_req);
974  seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs);
975  seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects);
976  seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias);
977  seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm);
978  seq_printf(m, "histogram_read_sectors ");
979  dasd_stats_array(m, data->dasd_read_secs);
980  seq_printf(m, "histogram_read_times ");
981  dasd_stats_array(m, data->dasd_read_times);
982  seq_printf(m, "histogram_read_time_build_to_ssch ");
983  dasd_stats_array(m, data->dasd_read_time1);
984  seq_printf(m, "histogram_read_time_ssch_to_irq ");
985  dasd_stats_array(m, data->dasd_read_time2);
986  seq_printf(m, "histogram_read_time_irq_to_end ");
987  dasd_stats_array(m, data->dasd_read_time3);
988  seq_printf(m, "histogram_read_ccw_queue_length ");
989  dasd_stats_array(m, data->dasd_read_nr_req);
990 }
991 
992 static int dasd_stats_show(struct seq_file *m, void *v)
993 {
994  struct dasd_profile *profile;
995  struct dasd_profile_info *data;
996 
997  profile = m->private;
998  spin_lock_bh(&profile->lock);
999  data = profile->data;
1000  if (!data) {
1001  spin_unlock_bh(&profile->lock);
1002  seq_printf(m, "disabled\n");
1003  return 0;
1004  }
1005  dasd_stats_seq_print(m, data);
1006  spin_unlock_bh(&profile->lock);
1007  return 0;
1008 }
1009 
1010 static int dasd_stats_open(struct inode *inode, struct file *file)
1011 {
1012  struct dasd_profile *profile = inode->i_private;
1013  return single_open(file, dasd_stats_show, profile);
1014 }
1015 
1016 static const struct file_operations dasd_stats_raw_fops = {
1017  .owner = THIS_MODULE,
1018  .open = dasd_stats_open,
1019  .read = seq_read,
1020  .llseek = seq_lseek,
1021  .release = single_release,
1022  .write = dasd_stats_write,
1023 };
1024 
1025 static ssize_t dasd_stats_global_write(struct file *file,
1026  const char __user *user_buf,
1027  size_t user_len, loff_t *pos)
1028 {
1029  char *buffer, *str;
1030  ssize_t rc;
1031 
1032  if (user_len > 65536)
1033  user_len = 65536;
1034  buffer = dasd_get_user_string(user_buf, user_len);
1035  if (IS_ERR(buffer))
1036  return PTR_ERR(buffer);
1037  str = skip_spaces(buffer);
1038  rc = user_len;
1039  if (strncmp(str, "reset", 5) == 0) {
1041  } else if (strncmp(str, "on", 2) == 0) {
1043  dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY;
1044  } else if (strncmp(str, "off", 3) == 0) {
1045  dasd_global_profile_level = DASD_PROFILE_OFF;
1046  } else
1047  rc = -EINVAL;
1048  vfree(buffer);
1049  return rc;
1050 }
1051 
1052 static int dasd_stats_global_show(struct seq_file *m, void *v)
1053 {
1054  if (!dasd_global_profile_level) {
1055  seq_printf(m, "disabled\n");
1056  return 0;
1057  }
1058  dasd_stats_seq_print(m, &dasd_global_profile_data);
1059  return 0;
1060 }
1061 
1062 static int dasd_stats_global_open(struct inode *inode, struct file *file)
1063 {
1064  return single_open(file, dasd_stats_global_show, NULL);
1065 }
1066 
1067 static const struct file_operations dasd_stats_global_fops = {
1068  .owner = THIS_MODULE,
1069  .open = dasd_stats_global_open,
1070  .read = seq_read,
1071  .llseek = seq_lseek,
1072  .release = single_release,
1073  .write = dasd_stats_global_write,
1074 };
1075 
1076 static void dasd_profile_init(struct dasd_profile *profile,
1077  struct dentry *base_dentry)
1078 {
1079  umode_t mode;
1080  struct dentry *pde;
1081 
1082  if (!base_dentry)
1083  return;
1084  profile->dentry = NULL;
1085  profile->data = NULL;
1086  mode = (S_IRUSR | S_IWUSR | S_IFREG);
1087  pde = debugfs_create_file("statistics", mode, base_dentry,
1088  profile, &dasd_stats_raw_fops);
1089  if (pde && !IS_ERR(pde))
1090  profile->dentry = pde;
1091  return;
1092 }
1093 
1094 static void dasd_profile_exit(struct dasd_profile *profile)
1095 {
1096  dasd_profile_off(profile);
1097  if (profile->dentry) {
1098  debugfs_remove(profile->dentry);
1099  profile->dentry = NULL;
1100  }
1101 }
1102 
1103 static void dasd_statistics_removeroot(void)
1104 {
1105  dasd_global_profile_level = DASD_PROFILE_OFF;
1106  if (dasd_global_profile_dentry) {
1107  debugfs_remove(dasd_global_profile_dentry);
1108  dasd_global_profile_dentry = NULL;
1109  }
1110  if (dasd_debugfs_global_entry)
1111  debugfs_remove(dasd_debugfs_global_entry);
1112  if (dasd_debugfs_root_entry)
1113  debugfs_remove(dasd_debugfs_root_entry);
1114 }
1115 
1116 static void dasd_statistics_createroot(void)
1117 {
1118  umode_t mode;
1119  struct dentry *pde;
1120 
1121  dasd_debugfs_root_entry = NULL;
1122  dasd_debugfs_global_entry = NULL;
1123  dasd_global_profile_dentry = NULL;
1124  pde = debugfs_create_dir("dasd", NULL);
1125  if (!pde || IS_ERR(pde))
1126  goto error;
1127  dasd_debugfs_root_entry = pde;
1128  pde = debugfs_create_dir("global", dasd_debugfs_root_entry);
1129  if (!pde || IS_ERR(pde))
1130  goto error;
1131  dasd_debugfs_global_entry = pde;
1132 
1133  mode = (S_IRUSR | S_IWUSR | S_IFREG);
1134  pde = debugfs_create_file("statistics", mode, dasd_debugfs_global_entry,
1135  NULL, &dasd_stats_global_fops);
1136  if (!pde || IS_ERR(pde))
1137  goto error;
1138  dasd_global_profile_dentry = pde;
1139  return;
1140 
1141 error:
1142  DBF_EVENT(DBF_ERR, "%s",
1143  "Creation of the dasd debugfs interface failed");
1144  dasd_statistics_removeroot();
1145  return;
1146 }
1147 
1148 #else
1149 #define dasd_profile_start(block, cqr, req) do {} while (0)
1150 #define dasd_profile_end(block, cqr, req) do {} while (0)
1151 
1152 static void dasd_statistics_createroot(void)
1153 {
1154  return;
1155 }
1156 
1157 static void dasd_statistics_removeroot(void)
1158 {
1159  return;
1160 }
1161 
1162 int dasd_stats_generic_show(struct seq_file *m, void *v)
1163 {
1164  seq_printf(m, "Statistics are not activated in this kernel\n");
1165  return 0;
1166 }
1167 
1168 static void dasd_profile_init(struct dasd_profile *profile,
1169  struct dentry *base_dentry)
1170 {
1171  return;
1172 }
1173 
1174 static void dasd_profile_exit(struct dasd_profile *profile)
1175 {
1176  return;
1177 }
1178 
1179 int dasd_profile_on(struct dasd_profile *profile)
1180 {
1181  return 0;
1182 }
1183 
1184 #endif /* CONFIG_DASD_PROFILE */
1185 
1186 /*
1187  * Allocate memory for a channel program with 'cplength' channel
1188  * command words and 'datasize' additional space. There are two
1189  * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed
1190  * memory and 2) dasd_smalloc_request uses the static ccw memory
1191  * that gets allocated for each device.
1192  */
1193 struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength,
1194  int datasize,
1195  struct dasd_device *device)
1196 {
1197  struct dasd_ccw_req *cqr;
1198 
1199  /* Sanity checks */
1200  BUG_ON(datasize > PAGE_SIZE ||
1201  (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
1202 
1203  cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
1204  if (cqr == NULL)
1205  return ERR_PTR(-ENOMEM);
1206  cqr->cpaddr = NULL;
1207  if (cplength > 0) {
1208  cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
1209  GFP_ATOMIC | GFP_DMA);
1210  if (cqr->cpaddr == NULL) {
1211  kfree(cqr);
1212  return ERR_PTR(-ENOMEM);
1213  }
1214  }
1215  cqr->data = NULL;
1216  if (datasize > 0) {
1217  cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA);
1218  if (cqr->data == NULL) {
1219  kfree(cqr->cpaddr);
1220  kfree(cqr);
1221  return ERR_PTR(-ENOMEM);
1222  }
1223  }
1224  cqr->magic = magic;
1226  dasd_get_device(device);
1227  return cqr;
1228 }
1229 
1230 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength,
1231  int datasize,
1232  struct dasd_device *device)
1233 {
1234  unsigned long flags;
1235  struct dasd_ccw_req *cqr;
1236  char *data;
1237  int size;
1238 
1239  size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
1240  if (cplength > 0)
1241  size += cplength * sizeof(struct ccw1);
1242  if (datasize > 0)
1243  size += datasize;
1244  spin_lock_irqsave(&device->mem_lock, flags);
1245  cqr = (struct dasd_ccw_req *)
1246  dasd_alloc_chunk(&device->ccw_chunks, size);
1247  spin_unlock_irqrestore(&device->mem_lock, flags);
1248  if (cqr == NULL)
1249  return ERR_PTR(-ENOMEM);
1250  memset(cqr, 0, sizeof(struct dasd_ccw_req));
1251  data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
1252  cqr->cpaddr = NULL;
1253  if (cplength > 0) {
1254  cqr->cpaddr = (struct ccw1 *) data;
1255  data += cplength*sizeof(struct ccw1);
1256  memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
1257  }
1258  cqr->data = NULL;
1259  if (datasize > 0) {
1260  cqr->data = data;
1261  memset(cqr->data, 0, datasize);
1262  }
1263  cqr->magic = magic;
1265  dasd_get_device(device);
1266  return cqr;
1267 }
1268 
1269 /*
1270  * Free memory of a channel program. This function needs to free all the
1271  * idal lists that might have been created by dasd_set_cda and the
1272  * struct dasd_ccw_req itself.
1273  */
1274 void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1275 {
1276 #ifdef CONFIG_64BIT
1277  struct ccw1 *ccw;
1278 
1279  /* Clear any idals used for the request. */
1280  ccw = cqr->cpaddr;
1281  do {
1282  clear_normalized_cda(ccw);
1283  } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
1284 #endif
1285  kfree(cqr->cpaddr);
1286  kfree(cqr->data);
1287  kfree(cqr);
1288  dasd_put_device(device);
1289 }
1290 
1291 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1292 {
1293  unsigned long flags;
1294 
1295  spin_lock_irqsave(&device->mem_lock, flags);
1296  dasd_free_chunk(&device->ccw_chunks, cqr);
1297  spin_unlock_irqrestore(&device->mem_lock, flags);
1298  dasd_put_device(device);
1299 }
1300 
1301 /*
1302  * Check discipline magic in cqr.
1303  */
1304 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
1305 {
1306  struct dasd_device *device;
1307 
1308  if (cqr == NULL)
1309  return -EINVAL;
1310  device = cqr->startdev;
1311  if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
1312  DBF_DEV_EVENT(DBF_WARNING, device,
1313  " dasd_ccw_req 0x%08x magic doesn't match"
1314  " discipline 0x%08x",
1315  cqr->magic,
1316  *(unsigned int *) device->discipline->name);
1317  return -EINVAL;
1318  }
1319  return 0;
1320 }
1321 
1322 /*
1323  * Terminate the current i/o and set the request to clear_pending.
1324  * Timer keeps device runnig.
1325  * ccw_device_clear can fail if the i/o subsystem
1326  * is in a bad mood.
1327  */
1328 int dasd_term_IO(struct dasd_ccw_req *cqr)
1329 {
1330  struct dasd_device *device;
1331  int retries, rc;
1332  char errorstring[ERRORLENGTH];
1333 
1334  /* Check the cqr */
1335  rc = dasd_check_cqr(cqr);
1336  if (rc)
1337  return rc;
1338  retries = 0;
1339  device = (struct dasd_device *) cqr->startdev;
1340  while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
1341  rc = ccw_device_clear(device->cdev, (long) cqr);
1342  switch (rc) {
1343  case 0: /* termination successful */
1344  cqr->status = DASD_CQR_CLEAR_PENDING;
1345  cqr->stopclk = get_clock();
1346  cqr->starttime = 0;
1347  DBF_DEV_EVENT(DBF_DEBUG, device,
1348  "terminate cqr %p successful",
1349  cqr);
1350  break;
1351  case -ENODEV:
1352  DBF_DEV_EVENT(DBF_ERR, device, "%s",
1353  "device gone, retry");
1354  break;
1355  case -EIO:
1356  DBF_DEV_EVENT(DBF_ERR, device, "%s",
1357  "I/O error, retry");
1358  break;
1359  case -EINVAL:
1360  case -EBUSY:
1361  DBF_DEV_EVENT(DBF_ERR, device, "%s",
1362  "device busy, retry later");
1363  break;
1364  default:
1365  /* internal error 10 - unknown rc*/
1366  snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
1367  dev_err(&device->cdev->dev, "An error occurred in the "
1368  "DASD device driver, reason=%s\n", errorstring);
1369  BUG();
1370  break;
1371  }
1372  retries++;
1373  }
1374  dasd_schedule_device_bh(device);
1375  return rc;
1376 }
1377 
1378 /*
1379  * Start the i/o. This start_IO can fail if the channel is really busy.
1380  * In that case set up a timer to start the request later.
1381  */
1382 int dasd_start_IO(struct dasd_ccw_req *cqr)
1383 {
1384  struct dasd_device *device;
1385  int rc;
1386  char errorstring[ERRORLENGTH];
1387 
1388  /* Check the cqr */
1389  rc = dasd_check_cqr(cqr);
1390  if (rc) {
1391  cqr->intrc = rc;
1392  return rc;
1393  }
1394  device = (struct dasd_device *) cqr->startdev;
1395  if (((cqr->block &&
1396  test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) ||
1397  test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) &&
1398  !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
1399  DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p "
1400  "because of stolen lock", cqr);
1401  cqr->status = DASD_CQR_ERROR;
1402  cqr->intrc = -EPERM;
1403  return -EPERM;
1404  }
1405  if (cqr->retries < 0) {
1406  /* internal error 14 - start_IO run out of retries */
1407  sprintf(errorstring, "14 %p", cqr);
1408  dev_err(&device->cdev->dev, "An error occurred in the DASD "
1409  "device driver, reason=%s\n", errorstring);
1410  cqr->status = DASD_CQR_ERROR;
1411  return -EIO;
1412  }
1413  cqr->startclk = get_clock();
1414  cqr->starttime = jiffies;
1415  cqr->retries--;
1416  if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1417  cqr->lpm &= device->path_data.opm;
1418  if (!cqr->lpm)
1419  cqr->lpm = device->path_data.opm;
1420  }
1421  if (cqr->cpmode == 1) {
1422  rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
1423  (long) cqr, cqr->lpm);
1424  } else {
1425  rc = ccw_device_start(device->cdev, cqr->cpaddr,
1426  (long) cqr, cqr->lpm, 0);
1427  }
1428  switch (rc) {
1429  case 0:
1430  cqr->status = DASD_CQR_IN_IO;
1431  break;
1432  case -EBUSY:
1433  DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1434  "start_IO: device busy, retry later");
1435  break;
1436  case -ETIMEDOUT:
1437  DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1438  "start_IO: request timeout, retry later");
1439  break;
1440  case -EACCES:
1441  /* -EACCES indicates that the request used only a subset of the
1442  * available paths and all these paths are gone. If the lpm of
1443  * this request was only a subset of the opm (e.g. the ppm) then
1444  * we just do a retry with all available paths.
1445  * If we already use the full opm, something is amiss, and we
1446  * need a full path verification.
1447  */
1448  if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1449  DBF_DEV_EVENT(DBF_WARNING, device,
1450  "start_IO: selected paths gone (%x)",
1451  cqr->lpm);
1452  } else if (cqr->lpm != device->path_data.opm) {
1453  cqr->lpm = device->path_data.opm;
1454  DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
1455  "start_IO: selected paths gone,"
1456  " retry on all paths");
1457  } else {
1458  DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1459  "start_IO: all paths in opm gone,"
1460  " do path verification");
1462  device->path_data.opm = 0;
1463  device->path_data.ppm = 0;
1464  device->path_data.npm = 0;
1465  device->path_data.tbvpm =
1466  ccw_device_get_path_mask(device->cdev);
1467  }
1468  break;
1469  case -ENODEV:
1470  DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1471  "start_IO: -ENODEV device gone, retry");
1472  break;
1473  case -EIO:
1474  DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1475  "start_IO: -EIO device gone, retry");
1476  break;
1477  case -EINVAL:
1478  /* most likely caused in power management context */
1479  DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1480  "start_IO: -EINVAL device currently "
1481  "not accessible");
1482  break;
1483  default:
1484  /* internal error 11 - unknown rc */
1485  snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
1486  dev_err(&device->cdev->dev,
1487  "An error occurred in the DASD device driver, "
1488  "reason=%s\n", errorstring);
1489  BUG();
1490  break;
1491  }
1492  cqr->intrc = rc;
1493  return rc;
1494 }
1495 
1496 /*
1497  * Timeout function for dasd devices. This is used for different purposes
1498  * 1) missing interrupt handler for normal operation
1499  * 2) delayed start of request where start_IO failed with -EBUSY
1500  * 3) timeout for missing state change interrupts
1501  * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
1502  * DASD_CQR_QUEUED for 2) and 3).
1503  */
1504 static void dasd_device_timeout(unsigned long ptr)
1505 {
1506  unsigned long flags;
1507  struct dasd_device *device;
1508 
1509  device = (struct dasd_device *) ptr;
1510  spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1511  /* re-activate request queue */
1513  spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1514  dasd_schedule_device_bh(device);
1515 }
1516 
1517 /*
1518  * Setup timeout for a device in jiffies.
1519  */
1520 void dasd_device_set_timer(struct dasd_device *device, int expires)
1521 {
1522  if (expires == 0)
1523  del_timer(&device->timer);
1524  else
1525  mod_timer(&device->timer, jiffies + expires);
1526 }
1527 
1528 /*
1529  * Clear timeout for a device.
1530  */
1532 {
1533  del_timer(&device->timer);
1534 }
1535 
1536 static void dasd_handle_killed_request(struct ccw_device *cdev,
1537  unsigned long intparm)
1538 {
1539  struct dasd_ccw_req *cqr;
1540  struct dasd_device *device;
1541 
1542  if (!intparm)
1543  return;
1544  cqr = (struct dasd_ccw_req *) intparm;
1545  if (cqr->status != DASD_CQR_IN_IO) {
1546  DBF_EVENT_DEVID(DBF_DEBUG, cdev,
1547  "invalid status in handle_killed_request: "
1548  "%02x", cqr->status);
1549  return;
1550  }
1551 
1552  device = dasd_device_from_cdev_locked(cdev);
1553  if (IS_ERR(device)) {
1554  DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1555  "unable to get device from cdev");
1556  return;
1557  }
1558 
1559  if (!cqr->startdev ||
1560  device != cqr->startdev ||
1561  strncmp(cqr->startdev->discipline->ebcname,
1562  (char *) &cqr->magic, 4)) {
1563  DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1564  "invalid device in request");
1565  dasd_put_device(device);
1566  return;
1567  }
1568 
1569  /* Schedule request to be retried. */
1570  cqr->status = DASD_CQR_QUEUED;
1571 
1572  dasd_device_clear_timer(device);
1573  dasd_schedule_device_bh(device);
1574  dasd_put_device(device);
1575 }
1576 
1578 {
1579  /* First of all start sense subsystem status request. */
1580  dasd_eer_snss(device);
1581 
1583  dasd_schedule_device_bh(device);
1584  if (device->block)
1585  dasd_schedule_block_bh(device->block);
1586 }
1587 
1588 /*
1589  * Interrupt handler for "normal" ssch-io based dasd devices.
1590  */
1591 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
1592  struct irb *irb)
1593 {
1594  struct dasd_ccw_req *cqr, *next;
1595  struct dasd_device *device;
1596  unsigned long long now;
1597  int expires;
1598 
1599  if (IS_ERR(irb)) {
1600  switch (PTR_ERR(irb)) {
1601  case -EIO:
1602  break;
1603  case -ETIMEDOUT:
1604  DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1605  "request timed out\n", __func__);
1606  break;
1607  default:
1608  DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1609  "unknown error %ld\n", __func__,
1610  PTR_ERR(irb));
1611  }
1612  dasd_handle_killed_request(cdev, intparm);
1613  return;
1614  }
1615 
1616  now = get_clock();
1617  cqr = (struct dasd_ccw_req *) intparm;
1618  /* check for conditions that should be handled immediately */
1619  if (!cqr ||
1620  !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1621  scsw_cstat(&irb->scsw) == 0)) {
1622  if (cqr)
1623  memcpy(&cqr->irb, irb, sizeof(*irb));
1624  device = dasd_device_from_cdev_locked(cdev);
1625  if (IS_ERR(device))
1626  return;
1627  /* ignore unsolicited interrupts for DIAG discipline */
1628  if (device->discipline == dasd_diag_discipline_pointer) {
1629  dasd_put_device(device);
1630  return;
1631  }
1632  device->discipline->dump_sense_dbf(device, irb, "int");
1633  if (device->features & DASD_FEATURE_ERPLOG)
1634  device->discipline->dump_sense(device, cqr, irb);
1635  device->discipline->check_for_device_change(device, cqr, irb);
1636  dasd_put_device(device);
1637  }
1638  if (!cqr)
1639  return;
1640 
1641  device = (struct dasd_device *) cqr->startdev;
1642  if (!device ||
1643  strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
1644  DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1645  "invalid device in request");
1646  return;
1647  }
1648 
1649  /* Check for clear pending */
1650  if (cqr->status == DASD_CQR_CLEAR_PENDING &&
1651  scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
1652  cqr->status = DASD_CQR_CLEARED;
1653  dasd_device_clear_timer(device);
1654  wake_up(&dasd_flush_wq);
1655  dasd_schedule_device_bh(device);
1656  return;
1657  }
1658 
1659  /* check status - the request might have been killed by dyn detach */
1660  if (cqr->status != DASD_CQR_IN_IO) {
1661  DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
1662  "status %02x", dev_name(&cdev->dev), cqr->status);
1663  return;
1664  }
1665 
1666  next = NULL;
1667  expires = 0;
1668  if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1669  scsw_cstat(&irb->scsw) == 0) {
1670  /* request was completed successfully */
1671  cqr->status = DASD_CQR_SUCCESS;
1672  cqr->stopclk = now;
1673  /* Start first request on queue if possible -> fast_io. */
1674  if (cqr->devlist.next != &device->ccw_queue) {
1675  next = list_entry(cqr->devlist.next,
1676  struct dasd_ccw_req, devlist);
1677  }
1678  } else { /* error */
1679  /*
1680  * If we don't want complex ERP for this request, then just
1681  * reset this and retry it in the fastpath
1682  */
1683  if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
1684  cqr->retries > 0) {
1685  if (cqr->lpm == device->path_data.opm)
1686  DBF_DEV_EVENT(DBF_DEBUG, device,
1687  "default ERP in fastpath "
1688  "(%i retries left)",
1689  cqr->retries);
1690  if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))
1691  cqr->lpm = device->path_data.opm;
1692  cqr->status = DASD_CQR_QUEUED;
1693  next = cqr;
1694  } else
1695  cqr->status = DASD_CQR_ERROR;
1696  }
1697  if (next && (next->status == DASD_CQR_QUEUED) &&
1698  (!device->stopped)) {
1699  if (device->discipline->start_IO(next) == 0)
1700  expires = next->expires;
1701  }
1702  if (expires != 0)
1703  dasd_device_set_timer(device, expires);
1704  else
1705  dasd_device_clear_timer(device);
1706  dasd_schedule_device_bh(device);
1707 }
1708 
1709 enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb)
1710 {
1711  struct dasd_device *device;
1712 
1713  device = dasd_device_from_cdev_locked(cdev);
1714 
1715  if (IS_ERR(device))
1716  goto out;
1717  if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
1718  device->state != device->target ||
1719  !device->discipline->check_for_device_change){
1720  dasd_put_device(device);
1721  goto out;
1722  }
1723  if (device->discipline->dump_sense_dbf)
1724  device->discipline->dump_sense_dbf(device, irb, "uc");
1725  device->discipline->check_for_device_change(device, NULL, irb);
1726  dasd_put_device(device);
1727 out:
1728  return UC_TODO_RETRY;
1729 }
1731 
1732 /*
1733  * If we have an error on a dasd_block layer request then we cancel
1734  * and return all further requests from the same dasd_block as well.
1735  */
1736 static void __dasd_device_recovery(struct dasd_device *device,
1737  struct dasd_ccw_req *ref_cqr)
1738 {
1739  struct list_head *l, *n;
1740  struct dasd_ccw_req *cqr;
1741 
1742  /*
1743  * only requeue request that came from the dasd_block layer
1744  */
1745  if (!ref_cqr->block)
1746  return;
1747 
1748  list_for_each_safe(l, n, &device->ccw_queue) {
1749  cqr = list_entry(l, struct dasd_ccw_req, devlist);
1750  if (cqr->status == DASD_CQR_QUEUED &&
1751  ref_cqr->block == cqr->block) {
1752  cqr->status = DASD_CQR_CLEARED;
1753  }
1754  }
1755 };
1756 
1757 /*
1758  * Remove those ccw requests from the queue that need to be returned
1759  * to the upper layer.
1760  */
1761 static void __dasd_device_process_ccw_queue(struct dasd_device *device,
1762  struct list_head *final_queue)
1763 {
1764  struct list_head *l, *n;
1765  struct dasd_ccw_req *cqr;
1766 
1767  /* Process request with final status. */
1768  list_for_each_safe(l, n, &device->ccw_queue) {
1769  cqr = list_entry(l, struct dasd_ccw_req, devlist);
1770 
1771  /* Stop list processing at the first non-final request. */
1772  if (cqr->status == DASD_CQR_QUEUED ||
1773  cqr->status == DASD_CQR_IN_IO ||
1775  break;
1776  if (cqr->status == DASD_CQR_ERROR) {
1777  __dasd_device_recovery(device, cqr);
1778  }
1779  /* Rechain finished requests to final queue */
1780  list_move_tail(&cqr->devlist, final_queue);
1781  }
1782 }
1783 
1784 /*
1785  * the cqrs from the final queue are returned to the upper layer
1786  * by setting a dasd_block state and calling the callback function
1787  */
1788 static void __dasd_device_process_final_queue(struct dasd_device *device,
1789  struct list_head *final_queue)
1790 {
1791  struct list_head *l, *n;
1792  struct dasd_ccw_req *cqr;
1793  struct dasd_block *block;
1794  void (*callback)(struct dasd_ccw_req *, void *data);
1795  void *callback_data;
1796  char errorstring[ERRORLENGTH];
1797 
1798  list_for_each_safe(l, n, final_queue) {
1799  cqr = list_entry(l, struct dasd_ccw_req, devlist);
1800  list_del_init(&cqr->devlist);
1801  block = cqr->block;
1802  callback = cqr->callback;
1803  callback_data = cqr->callback_data;
1804  if (block)
1805  spin_lock_bh(&block->queue_lock);
1806  switch (cqr->status) {
1807  case DASD_CQR_SUCCESS:
1808  cqr->status = DASD_CQR_DONE;
1809  break;
1810  case DASD_CQR_ERROR:
1811  cqr->status = DASD_CQR_NEED_ERP;
1812  break;
1813  case DASD_CQR_CLEARED:
1814  cqr->status = DASD_CQR_TERMINATED;
1815  break;
1816  default:
1817  /* internal error 12 - wrong cqr status*/
1818  snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
1819  dev_err(&device->cdev->dev,
1820  "An error occurred in the DASD device driver, "
1821  "reason=%s\n", errorstring);
1822  BUG();
1823  }
1824  if (cqr->callback != NULL)
1825  (callback)(cqr, callback_data);
1826  if (block)
1827  spin_unlock_bh(&block->queue_lock);
1828  }
1829 }
1830 
1831 /*
1832  * Take a look at the first request on the ccw queue and check
1833  * if it reached its expire time. If so, terminate the IO.
1834  */
1835 static void __dasd_device_check_expire(struct dasd_device *device)
1836 {
1837  struct dasd_ccw_req *cqr;
1838 
1839  if (list_empty(&device->ccw_queue))
1840  return;
1841  cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1842  if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
1843  (time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
1844  if (device->discipline->term_IO(cqr) != 0) {
1845  /* Hmpf, try again in 5 sec */
1846  dev_err(&device->cdev->dev,
1847  "cqr %p timed out (%lus) but cannot be "
1848  "ended, retrying in 5 s\n",
1849  cqr, (cqr->expires/HZ));
1850  cqr->expires += 5*HZ;
1851  dasd_device_set_timer(device, 5*HZ);
1852  } else {
1853  dev_err(&device->cdev->dev,
1854  "cqr %p timed out (%lus), %i retries "
1855  "remaining\n", cqr, (cqr->expires/HZ),
1856  cqr->retries);
1857  }
1858  }
1859 }
1860 
1861 /*
1862  * Take a look at the first request on the ccw queue and check
1863  * if it needs to be started.
1864  */
1865 static void __dasd_device_start_head(struct dasd_device *device)
1866 {
1867  struct dasd_ccw_req *cqr;
1868  int rc;
1869 
1870  if (list_empty(&device->ccw_queue))
1871  return;
1872  cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1873  if (cqr->status != DASD_CQR_QUEUED)
1874  return;
1875  /* when device is stopped, return request to previous layer
1876  * exception: only the disconnect or unresumed bits are set and the
1877  * cqr is a path verification request
1878  */
1879  if (device->stopped &&
1880  !(!(device->stopped & ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
1881  && test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))) {
1882  cqr->intrc = -EAGAIN;
1883  cqr->status = DASD_CQR_CLEARED;
1884  dasd_schedule_device_bh(device);
1885  return;
1886  }
1887 
1888  rc = device->discipline->start_IO(cqr);
1889  if (rc == 0)
1890  dasd_device_set_timer(device, cqr->expires);
1891  else if (rc == -EACCES) {
1892  dasd_schedule_device_bh(device);
1893  } else
1894  /* Hmpf, try again in 1/2 sec */
1895  dasd_device_set_timer(device, 50);
1896 }
1897 
1898 static void __dasd_device_check_path_events(struct dasd_device *device)
1899 {
1900  int rc;
1901 
1902  if (device->path_data.tbvpm) {
1903  if (device->stopped & ~(DASD_STOPPED_DC_WAIT |
1905  return;
1906  rc = device->discipline->verify_path(
1907  device, device->path_data.tbvpm);
1908  if (rc)
1909  dasd_device_set_timer(device, 50);
1910  else
1911  device->path_data.tbvpm = 0;
1912  }
1913 };
1914 
1915 /*
1916  * Go through all request on the dasd_device request queue,
1917  * terminate them on the cdev if necessary, and return them to the
1918  * submitting layer via callback.
1919  * Note:
1920  * Make sure that all 'submitting layers' still exist when
1921  * this function is called!. In other words, when 'device' is a base
1922  * device then all block layer requests must have been removed before
1923  * via dasd_flush_block_queue.
1924  */
1926 {
1927  struct dasd_ccw_req *cqr, *n;
1928  int rc;
1929  struct list_head flush_queue;
1930 
1931  INIT_LIST_HEAD(&flush_queue);
1932  spin_lock_irq(get_ccwdev_lock(device->cdev));
1933  rc = 0;
1934  list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
1935  /* Check status and move request to flush_queue */
1936  switch (cqr->status) {
1937  case DASD_CQR_IN_IO:
1938  rc = device->discipline->term_IO(cqr);
1939  if (rc) {
1940  /* unable to terminate requeust */
1941  dev_err(&device->cdev->dev,
1942  "Flushing the DASD request queue "
1943  "failed for request %p\n", cqr);
1944  /* stop flush processing */
1945  goto finished;
1946  }
1947  break;
1948  case DASD_CQR_QUEUED:
1949  cqr->stopclk = get_clock();
1950  cqr->status = DASD_CQR_CLEARED;
1951  break;
1952  default: /* no need to modify the others */
1953  break;
1954  }
1955  list_move_tail(&cqr->devlist, &flush_queue);
1956  }
1957 finished:
1958  spin_unlock_irq(get_ccwdev_lock(device->cdev));
1959  /*
1960  * After this point all requests must be in state CLEAR_PENDING,
1961  * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
1962  * one of the others.
1963  */
1964  list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
1965  wait_event(dasd_flush_wq,
1966  (cqr->status != DASD_CQR_CLEAR_PENDING));
1967  /*
1968  * Now set each request back to TERMINATED, DONE or NEED_ERP
1969  * and call the callback function of flushed requests
1970  */
1971  __dasd_device_process_final_queue(device, &flush_queue);
1972  return rc;
1973 }
1974 
1975 /*
1976  * Acquire the device lock and process queues for the device.
1977  */
1978 static void dasd_device_tasklet(struct dasd_device *device)
1979 {
1980  struct list_head final_queue;
1981 
1982  atomic_set (&device->tasklet_scheduled, 0);
1983  INIT_LIST_HEAD(&final_queue);
1984  spin_lock_irq(get_ccwdev_lock(device->cdev));
1985  /* Check expire time of first request on the ccw queue. */
1986  __dasd_device_check_expire(device);
1987  /* find final requests on ccw queue */
1988  __dasd_device_process_ccw_queue(device, &final_queue);
1989  __dasd_device_check_path_events(device);
1990  spin_unlock_irq(get_ccwdev_lock(device->cdev));
1991  /* Now call the callback function of requests with final status */
1992  __dasd_device_process_final_queue(device, &final_queue);
1993  spin_lock_irq(get_ccwdev_lock(device->cdev));
1994  /* Now check if the head of the ccw queue needs to be started. */
1995  __dasd_device_start_head(device);
1996  spin_unlock_irq(get_ccwdev_lock(device->cdev));
1997  if (waitqueue_active(&shutdown_waitq))
1998  wake_up(&shutdown_waitq);
1999  dasd_put_device(device);
2000 }
2001 
2002 /*
2003  * Schedules a call to dasd_tasklet over the device tasklet.
2004  */
2006 {
2007  /* Protect against rescheduling. */
2008  if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
2009  return;
2010  dasd_get_device(device);
2011  tasklet_hi_schedule(&device->tasklet);
2012 }
2013 
2014 void dasd_device_set_stop_bits(struct dasd_device *device, int bits)
2015 {
2016  device->stopped |= bits;
2017 }
2019 
2021 {
2022  device->stopped &= ~bits;
2023  if (!device->stopped)
2024  wake_up(&generic_waitq);
2025 }
2027 
2028 /*
2029  * Queue a request to the head of the device ccw_queue.
2030  * Start the I/O if possible.
2031  */
2033 {
2034  struct dasd_device *device;
2035  unsigned long flags;
2036 
2037  device = cqr->startdev;
2038  spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2039  cqr->status = DASD_CQR_QUEUED;
2040  list_add(&cqr->devlist, &device->ccw_queue);
2041  /* let the bh start the request to keep them in order */
2042  dasd_schedule_device_bh(device);
2043  spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2044 }
2045 
2046 /*
2047  * Queue a request to the tail of the device ccw_queue.
2048  * Start the I/O if possible.
2049  */
2051 {
2052  struct dasd_device *device;
2053  unsigned long flags;
2054 
2055  device = cqr->startdev;
2056  spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2057  cqr->status = DASD_CQR_QUEUED;
2058  list_add_tail(&cqr->devlist, &device->ccw_queue);
2059  /* let the bh start the request to keep them in order */
2060  dasd_schedule_device_bh(device);
2061  spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2062 }
2063 
2064 /*
2065  * Wakeup helper for the 'sleep_on' functions.
2066  */
2067 void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
2068 {
2069  spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2071  spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2072  wake_up(&generic_waitq);
2073 }
2075 
2076 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
2077 {
2078  struct dasd_device *device;
2079  int rc;
2080 
2081  device = cqr->startdev;
2082  spin_lock_irq(get_ccwdev_lock(device->cdev));
2083  rc = (cqr->callback_data == DASD_SLEEPON_END_TAG);
2084  spin_unlock_irq(get_ccwdev_lock(device->cdev));
2085  return rc;
2086 }
2087 
2088 /*
2089  * checks if error recovery is necessary, returns 1 if yes, 0 otherwise.
2090  */
2091 static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr)
2092 {
2093  struct dasd_device *device;
2094  dasd_erp_fn_t erp_fn;
2095 
2096  if (cqr->status == DASD_CQR_FILLED)
2097  return 0;
2098  device = cqr->startdev;
2099  if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2100  if (cqr->status == DASD_CQR_TERMINATED) {
2101  device->discipline->handle_terminated_request(cqr);
2102  return 1;
2103  }
2104  if (cqr->status == DASD_CQR_NEED_ERP) {
2105  erp_fn = device->discipline->erp_action(cqr);
2106  erp_fn(cqr);
2107  return 1;
2108  }
2109  if (cqr->status == DASD_CQR_FAILED)
2110  dasd_log_sense(cqr, &cqr->irb);
2111  if (cqr->refers) {
2112  __dasd_process_erp(device, cqr);
2113  return 1;
2114  }
2115  }
2116  return 0;
2117 }
2118 
2119 static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr)
2120 {
2121  if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2122  if (cqr->refers) /* erp is not done yet */
2123  return 1;
2124  return ((cqr->status != DASD_CQR_DONE) &&
2125  (cqr->status != DASD_CQR_FAILED));
2126  } else
2127  return (cqr->status == DASD_CQR_FILLED);
2128 }
2129 
2130 static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
2131 {
2132  struct dasd_device *device;
2133  int rc;
2134  struct list_head ccw_queue;
2135  struct dasd_ccw_req *cqr;
2136 
2137  INIT_LIST_HEAD(&ccw_queue);
2138  maincqr->status = DASD_CQR_FILLED;
2139  device = maincqr->startdev;
2140  list_add(&maincqr->blocklist, &ccw_queue);
2141  for (cqr = maincqr; __dasd_sleep_on_loop_condition(cqr);
2142  cqr = list_first_entry(&ccw_queue,
2143  struct dasd_ccw_req, blocklist)) {
2144 
2145  if (__dasd_sleep_on_erp(cqr))
2146  continue;
2147  if (cqr->status != DASD_CQR_FILLED) /* could be failed */
2148  continue;
2149  if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2150  !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2151  cqr->status = DASD_CQR_FAILED;
2152  cqr->intrc = -EPERM;
2153  continue;
2154  }
2155  /* Non-temporary stop condition will trigger fail fast */
2156  if (device->stopped & ~DASD_STOPPED_PENDING &&
2158  (!dasd_eer_enabled(device))) {
2159  cqr->status = DASD_CQR_FAILED;
2160  cqr->intrc = -EAGAIN;
2161  continue;
2162  }
2163  /* Don't try to start requests if device is stopped */
2164  if (interruptible) {
2166  generic_waitq, !(device->stopped));
2167  if (rc == -ERESTARTSYS) {
2168  cqr->status = DASD_CQR_FAILED;
2169  maincqr->intrc = rc;
2170  continue;
2171  }
2172  } else
2173  wait_event(generic_waitq, !(device->stopped));
2174 
2175  if (!cqr->callback)
2176  cqr->callback = dasd_wakeup_cb;
2177 
2179  dasd_add_request_tail(cqr);
2180  if (interruptible) {
2182  generic_waitq, _wait_for_wakeup(cqr));
2183  if (rc == -ERESTARTSYS) {
2184  dasd_cancel_req(cqr);
2185  /* wait (non-interruptible) for final status */
2186  wait_event(generic_waitq,
2187  _wait_for_wakeup(cqr));
2188  cqr->status = DASD_CQR_FAILED;
2189  maincqr->intrc = rc;
2190  continue;
2191  }
2192  } else
2193  wait_event(generic_waitq, _wait_for_wakeup(cqr));
2194  }
2195 
2196  maincqr->endclk = get_clock();
2197  if ((maincqr->status != DASD_CQR_DONE) &&
2198  (maincqr->intrc != -ERESTARTSYS))
2199  dasd_log_sense(maincqr, &maincqr->irb);
2200  if (maincqr->status == DASD_CQR_DONE)
2201  rc = 0;
2202  else if (maincqr->intrc)
2203  rc = maincqr->intrc;
2204  else
2205  rc = -EIO;
2206  return rc;
2207 }
2208 
2209 /*
2210  * Queue a request to the tail of the device ccw_queue and wait for
2211  * it's completion.
2212  */
2213 int dasd_sleep_on(struct dasd_ccw_req *cqr)
2214 {
2215  return _dasd_sleep_on(cqr, 0);
2216 }
2217 
2218 /*
2219  * Queue a request to the tail of the device ccw_queue and wait
2220  * interruptible for it's completion.
2221  */
2223 {
2224  return _dasd_sleep_on(cqr, 1);
2225 }
2226 
2227 /*
2228  * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
2229  * for eckd devices) the currently running request has to be terminated
2230  * and be put back to status queued, before the special request is added
2231  * to the head of the queue. Then the special request is waited on normally.
2232  */
2233 static inline int _dasd_term_running_cqr(struct dasd_device *device)
2234 {
2235  struct dasd_ccw_req *cqr;
2236  int rc;
2237 
2238  if (list_empty(&device->ccw_queue))
2239  return 0;
2240  cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2241  rc = device->discipline->term_IO(cqr);
2242  if (!rc)
2243  /*
2244  * CQR terminated because a more important request is pending.
2245  * Undo decreasing of retry counter because this is
2246  * not an error case.
2247  */
2248  cqr->retries++;
2249  return rc;
2250 }
2251 
2253 {
2254  struct dasd_device *device;
2255  int rc;
2256 
2257  device = cqr->startdev;
2258  if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2259  !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2260  cqr->status = DASD_CQR_FAILED;
2261  cqr->intrc = -EPERM;
2262  return -EIO;
2263  }
2264  spin_lock_irq(get_ccwdev_lock(device->cdev));
2265  rc = _dasd_term_running_cqr(device);
2266  if (rc) {
2267  spin_unlock_irq(get_ccwdev_lock(device->cdev));
2268  return rc;
2269  }
2270  cqr->callback = dasd_wakeup_cb;
2272  cqr->status = DASD_CQR_QUEUED;
2273  /*
2274  * add new request as second
2275  * first the terminated cqr needs to be finished
2276  */
2277  list_add(&cqr->devlist, device->ccw_queue.next);
2278 
2279  /* let the bh start the request to keep them in order */
2280  dasd_schedule_device_bh(device);
2281 
2282  spin_unlock_irq(get_ccwdev_lock(device->cdev));
2283 
2284  wait_event(generic_waitq, _wait_for_wakeup(cqr));
2285 
2286  if (cqr->status == DASD_CQR_DONE)
2287  rc = 0;
2288  else if (cqr->intrc)
2289  rc = cqr->intrc;
2290  else
2291  rc = -EIO;
2292  return rc;
2293 }
2294 
2295 /*
2296  * Cancels a request that was started with dasd_sleep_on_req.
2297  * This is useful to timeout requests. The request will be
2298  * terminated if it is currently in i/o.
2299  * Returns 1 if the request has been terminated.
2300  * 0 if there was no need to terminate the request (not started yet)
2301  * negative error code if termination failed
2302  * Cancellation of a request is an asynchronous operation! The calling
2303  * function has to wait until the request is properly returned via callback.
2304  */
2306 {
2307  struct dasd_device *device = cqr->startdev;
2308  unsigned long flags;
2309  int rc;
2310 
2311  rc = 0;
2312  spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2313  switch (cqr->status) {
2314  case DASD_CQR_QUEUED:
2315  /* request was not started - just set to cleared */
2316  cqr->status = DASD_CQR_CLEARED;
2317  break;
2318  case DASD_CQR_IN_IO:
2319  /* request in IO - terminate IO and release again */
2320  rc = device->discipline->term_IO(cqr);
2321  if (rc) {
2322  dev_err(&device->cdev->dev,
2323  "Cancelling request %p failed with rc=%d\n",
2324  cqr, rc);
2325  } else {
2326  cqr->stopclk = get_clock();
2327  }
2328  break;
2329  default: /* already finished or clear pending - do nothing */
2330  break;
2331  }
2332  spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2333  dasd_schedule_device_bh(device);
2334  return rc;
2335 }
2336 
2337 
2338 /*
2339  * SECTION: Operations of the dasd_block layer.
2340  */
2341 
2342 /*
2343  * Timeout function for dasd_block. This is used when the block layer
2344  * is waiting for something that may not come reliably, (e.g. a state
2345  * change interrupt)
2346  */
2347 static void dasd_block_timeout(unsigned long ptr)
2348 {
2349  unsigned long flags;
2350  struct dasd_block *block;
2351 
2352  block = (struct dasd_block *) ptr;
2353  spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
2354  /* re-activate request queue */
2356  spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
2357  dasd_schedule_block_bh(block);
2358 }
2359 
2360 /*
2361  * Setup timeout for a dasd_block in jiffies.
2362  */
2363 void dasd_block_set_timer(struct dasd_block *block, int expires)
2364 {
2365  if (expires == 0)
2366  del_timer(&block->timer);
2367  else
2368  mod_timer(&block->timer, jiffies + expires);
2369 }
2370 
2371 /*
2372  * Clear timeout for a dasd_block.
2373  */
2375 {
2376  del_timer(&block->timer);
2377 }
2378 
2379 /*
2380  * Process finished error recovery ccw.
2381  */
2382 static void __dasd_process_erp(struct dasd_device *device,
2383  struct dasd_ccw_req *cqr)
2384 {
2385  dasd_erp_fn_t erp_fn;
2386 
2387  if (cqr->status == DASD_CQR_DONE)
2388  DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
2389  else
2390  dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
2391  erp_fn = device->discipline->erp_postaction(cqr);
2392  erp_fn(cqr);
2393 }
2394 
2395 /*
2396  * Fetch requests from the block device queue.
2397  */
2398 static void __dasd_process_request_queue(struct dasd_block *block)
2399 {
2400  struct request_queue *queue;
2401  struct request *req;
2402  struct dasd_ccw_req *cqr;
2403  struct dasd_device *basedev;
2404  unsigned long flags;
2405  queue = block->request_queue;
2406  basedev = block->base;
2407  /* No queue ? Then there is nothing to do. */
2408  if (queue == NULL)
2409  return;
2410 
2411  /*
2412  * We requeue request from the block device queue to the ccw
2413  * queue only in two states. In state DASD_STATE_READY the
2414  * partition detection is done and we need to requeue requests
2415  * for that. State DASD_STATE_ONLINE is normal block device
2416  * operation.
2417  */
2418  if (basedev->state < DASD_STATE_READY) {
2419  while ((req = blk_fetch_request(block->request_queue)))
2420  __blk_end_request_all(req, -EIO);
2421  return;
2422  }
2423  /* Now we try to fetch requests from the request queue */
2424  while ((req = blk_peek_request(queue))) {
2425  if (basedev->features & DASD_FEATURE_READONLY &&
2426  rq_data_dir(req) == WRITE) {
2427  DBF_DEV_EVENT(DBF_ERR, basedev,
2428  "Rejecting write request %p",
2429  req);
2430  blk_start_request(req);
2431  __blk_end_request_all(req, -EIO);
2432  continue;
2433  }
2434  cqr = basedev->discipline->build_cp(basedev, block, req);
2435  if (IS_ERR(cqr)) {
2436  if (PTR_ERR(cqr) == -EBUSY)
2437  break; /* normal end condition */
2438  if (PTR_ERR(cqr) == -ENOMEM)
2439  break; /* terminate request queue loop */
2440  if (PTR_ERR(cqr) == -EAGAIN) {
2441  /*
2442  * The current request cannot be build right
2443  * now, we have to try later. If this request
2444  * is the head-of-queue we stop the device
2445  * for 1/2 second.
2446  */
2447  if (!list_empty(&block->ccw_queue))
2448  break;
2450  get_ccwdev_lock(basedev->cdev), flags);
2451  dasd_device_set_stop_bits(basedev,
2453  spin_unlock_irqrestore(
2454  get_ccwdev_lock(basedev->cdev), flags);
2455  dasd_block_set_timer(block, HZ/2);
2456  break;
2457  }
2458  DBF_DEV_EVENT(DBF_ERR, basedev,
2459  "CCW creation failed (rc=%ld) "
2460  "on request %p",
2461  PTR_ERR(cqr), req);
2462  blk_start_request(req);
2463  __blk_end_request_all(req, -EIO);
2464  continue;
2465  }
2466  /*
2467  * Note: callback is set to dasd_return_cqr_cb in
2468  * __dasd_block_start_head to cover erp requests as well
2469  */
2470  cqr->callback_data = (void *) req;
2471  cqr->status = DASD_CQR_FILLED;
2472  blk_start_request(req);
2473  list_add_tail(&cqr->blocklist, &block->ccw_queue);
2474  dasd_profile_start(block, cqr, req);
2475  }
2476 }
2477 
2478 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
2479 {
2480  struct request *req;
2481  int status;
2482  int error = 0;
2483 
2484  req = (struct request *) cqr->callback_data;
2485  dasd_profile_end(cqr->block, cqr, req);
2486  status = cqr->block->base->discipline->free_cp(cqr, req);
2487  if (status <= 0)
2488  error = status ? status : -EIO;
2489  __blk_end_request_all(req, error);
2490 }
2491 
2492 /*
2493  * Process ccw request queue.
2494  */
2495 static void __dasd_process_block_ccw_queue(struct dasd_block *block,
2496  struct list_head *final_queue)
2497 {
2498  struct list_head *l, *n;
2499  struct dasd_ccw_req *cqr;
2500  dasd_erp_fn_t erp_fn;
2501  unsigned long flags;
2502  struct dasd_device *base = block->base;
2503 
2504 restart:
2505  /* Process request with final status. */
2506  list_for_each_safe(l, n, &block->ccw_queue) {
2507  cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2508  if (cqr->status != DASD_CQR_DONE &&
2509  cqr->status != DASD_CQR_FAILED &&
2510  cqr->status != DASD_CQR_NEED_ERP &&
2511  cqr->status != DASD_CQR_TERMINATED)
2512  continue;
2513 
2514  if (cqr->status == DASD_CQR_TERMINATED) {
2515  base->discipline->handle_terminated_request(cqr);
2516  goto restart;
2517  }
2518 
2519  /* Process requests that may be recovered */
2520  if (cqr->status == DASD_CQR_NEED_ERP) {
2521  erp_fn = base->discipline->erp_action(cqr);
2522  if (IS_ERR(erp_fn(cqr)))
2523  continue;
2524  goto restart;
2525  }
2526 
2527  /* log sense for fatal error */
2528  if (cqr->status == DASD_CQR_FAILED) {
2529  dasd_log_sense(cqr, &cqr->irb);
2530  }
2531 
2532  /* First of all call extended error reporting. */
2533  if (dasd_eer_enabled(base) &&
2534  cqr->status == DASD_CQR_FAILED) {
2535  dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
2536 
2537  /* restart request */
2538  cqr->status = DASD_CQR_FILLED;
2539  cqr->retries = 255;
2540  spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
2542  spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
2543  flags);
2544  goto restart;
2545  }
2546 
2547  /* Process finished ERP request. */
2548  if (cqr->refers) {
2549  __dasd_process_erp(base, cqr);
2550  goto restart;
2551  }
2552 
2553  /* Rechain finished requests to final queue */
2554  cqr->endclk = get_clock();
2555  list_move_tail(&cqr->blocklist, final_queue);
2556  }
2557 }
2558 
2559 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
2560 {
2562 }
2563 
2564 static void __dasd_block_start_head(struct dasd_block *block)
2565 {
2566  struct dasd_ccw_req *cqr;
2567 
2568  if (list_empty(&block->ccw_queue))
2569  return;
2570  /* We allways begin with the first requests on the queue, as some
2571  * of previously started requests have to be enqueued on a
2572  * dasd_device again for error recovery.
2573  */
2574  list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
2575  if (cqr->status != DASD_CQR_FILLED)
2576  continue;
2577  if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) &&
2578  !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2579  cqr->status = DASD_CQR_FAILED;
2580  cqr->intrc = -EPERM;
2581  dasd_schedule_block_bh(block);
2582  continue;
2583  }
2584  /* Non-temporary stop condition will trigger fail fast */
2585  if (block->base->stopped & ~DASD_STOPPED_PENDING &&
2587  (!dasd_eer_enabled(block->base))) {
2588  cqr->status = DASD_CQR_FAILED;
2589  dasd_schedule_block_bh(block);
2590  continue;
2591  }
2592  /* Don't try to start requests if device is stopped */
2593  if (block->base->stopped)
2594  return;
2595 
2596  /* just a fail safe check, should not happen */
2597  if (!cqr->startdev)
2598  cqr->startdev = block->base;
2599 
2600  /* make sure that the requests we submit find their way back */
2601  cqr->callback = dasd_return_cqr_cb;
2602 
2603  dasd_add_request_tail(cqr);
2604  }
2605 }
2606 
2607 /*
2608  * Central dasd_block layer routine. Takes requests from the generic
2609  * block layer request queue, creates ccw requests, enqueues them on
2610  * a dasd_device and processes ccw requests that have been returned.
2611  */
2612 static void dasd_block_tasklet(struct dasd_block *block)
2613 {
2614  struct list_head final_queue;
2615  struct list_head *l, *n;
2616  struct dasd_ccw_req *cqr;
2617 
2618  atomic_set(&block->tasklet_scheduled, 0);
2619  INIT_LIST_HEAD(&final_queue);
2620  spin_lock(&block->queue_lock);
2621  /* Finish off requests on ccw queue */
2622  __dasd_process_block_ccw_queue(block, &final_queue);
2623  spin_unlock(&block->queue_lock);
2624  /* Now call the callback function of requests with final status */
2625  spin_lock_irq(&block->request_queue_lock);
2626  list_for_each_safe(l, n, &final_queue) {
2627  cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2628  list_del_init(&cqr->blocklist);
2629  __dasd_cleanup_cqr(cqr);
2630  }
2631  spin_lock(&block->queue_lock);
2632  /* Get new request from the block device request queue */
2633  __dasd_process_request_queue(block);
2634  /* Now check if the head of the ccw queue needs to be started. */
2635  __dasd_block_start_head(block);
2636  spin_unlock(&block->queue_lock);
2637  spin_unlock_irq(&block->request_queue_lock);
2638  if (waitqueue_active(&shutdown_waitq))
2639  wake_up(&shutdown_waitq);
2640  dasd_put_device(block->base);
2641 }
2642 
2643 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
2644 {
2645  wake_up(&dasd_flush_wq);
2646 }
2647 
2648 /*
2649  * Go through all request on the dasd_block request queue, cancel them
2650  * on the respective dasd_device, and return them to the generic
2651  * block layer.
2652  */
2653 static int dasd_flush_block_queue(struct dasd_block *block)
2654 {
2655  struct dasd_ccw_req *cqr, *n;
2656  int rc, i;
2657  struct list_head flush_queue;
2658 
2659  INIT_LIST_HEAD(&flush_queue);
2660  spin_lock_bh(&block->queue_lock);
2661  rc = 0;
2662 restart:
2663  list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
2664  /* if this request currently owned by a dasd_device cancel it */
2665  if (cqr->status >= DASD_CQR_QUEUED)
2666  rc = dasd_cancel_req(cqr);
2667  if (rc < 0)
2668  break;
2669  /* Rechain request (including erp chain) so it won't be
2670  * touched by the dasd_block_tasklet anymore.
2671  * Replace the callback so we notice when the request
2672  * is returned from the dasd_device layer.
2673  */
2674  cqr->callback = _dasd_wake_block_flush_cb;
2675  for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
2676  list_move_tail(&cqr->blocklist, &flush_queue);
2677  if (i > 1)
2678  /* moved more than one request - need to restart */
2679  goto restart;
2680  }
2681  spin_unlock_bh(&block->queue_lock);
2682  /* Now call the callback function of flushed requests */
2683 restart_cb:
2684  list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
2685  wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
2686  /* Process finished ERP request. */
2687  if (cqr->refers) {
2688  spin_lock_bh(&block->queue_lock);
2689  __dasd_process_erp(block->base, cqr);
2690  spin_unlock_bh(&block->queue_lock);
2691  /* restart list_for_xx loop since dasd_process_erp
2692  * might remove multiple elements */
2693  goto restart_cb;
2694  }
2695  /* call the callback function */
2696  spin_lock_irq(&block->request_queue_lock);
2697  cqr->endclk = get_clock();
2698  list_del_init(&cqr->blocklist);
2699  __dasd_cleanup_cqr(cqr);
2700  spin_unlock_irq(&block->request_queue_lock);
2701  }
2702  return rc;
2703 }
2704 
2705 /*
2706  * Schedules a call to dasd_tasklet over the device tasklet.
2707  */
2709 {
2710  /* Protect against rescheduling. */
2711  if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
2712  return;
2713  /* life cycle of block is bound to it's base device */
2714  dasd_get_device(block->base);
2715  tasklet_hi_schedule(&block->tasklet);
2716 }
2717 
2718 
2719 /*
2720  * SECTION: external block device operations
2721  * (request queue handling, open, release, etc.)
2722  */
2723 
2724 /*
2725  * Dasd request queue function. Called from ll_rw_blk.c
2726  */
2727 static void do_dasd_request(struct request_queue *queue)
2728 {
2729  struct dasd_block *block;
2730 
2731  block = queue->queuedata;
2732  spin_lock(&block->queue_lock);
2733  /* Get new request from the block device request queue */
2734  __dasd_process_request_queue(block);
2735  /* Now check if the head of the ccw queue needs to be started. */
2736  __dasd_block_start_head(block);
2737  spin_unlock(&block->queue_lock);
2738 }
2739 
2740 /*
2741  * Allocate and initialize request queue and default I/O scheduler.
2742  */
2743 static int dasd_alloc_queue(struct dasd_block *block)
2744 {
2745  int rc;
2746 
2747  block->request_queue = blk_init_queue(do_dasd_request,
2748  &block->request_queue_lock);
2749  if (block->request_queue == NULL)
2750  return -ENOMEM;
2751 
2752  block->request_queue->queuedata = block;
2753 
2754  elevator_exit(block->request_queue->elevator);
2755  block->request_queue->elevator = NULL;
2756  rc = elevator_init(block->request_queue, "deadline");
2757  if (rc) {
2759  return rc;
2760  }
2761  return 0;
2762 }
2763 
2764 /*
2765  * Allocate and initialize request queue.
2766  */
2767 static void dasd_setup_queue(struct dasd_block *block)
2768 {
2769  int max;
2770 
2771  if (block->base->features & DASD_FEATURE_USERAW) {
2772  /*
2773  * the max_blocks value for raw_track access is 256
2774  * it is higher than the native ECKD value because we
2775  * only need one ccw per track
2776  * so the max_hw_sectors are
2777  * 2048 x 512B = 1024kB = 16 tracks
2778  */
2779  max = 2048;
2780  } else {
2781  max = block->base->discipline->max_blocks << block->s2b_shift;
2782  }
2784  block->bp_block);
2787  /* with page sized segments we can translate each segement into
2788  * one idaw/tidaw
2789  */
2792 }
2793 
2794 /*
2795  * Deactivate and free request queue.
2796  */
2797 static void dasd_free_queue(struct dasd_block *block)
2798 {
2799  if (block->request_queue) {
2801  block->request_queue = NULL;
2802  }
2803 }
2804 
2805 /*
2806  * Flush request on the request queue.
2807  */
2808 static void dasd_flush_request_queue(struct dasd_block *block)
2809 {
2810  struct request *req;
2811 
2812  if (!block->request_queue)
2813  return;
2814 
2815  spin_lock_irq(&block->request_queue_lock);
2816  while ((req = blk_fetch_request(block->request_queue)))
2817  __blk_end_request_all(req, -EIO);
2818  spin_unlock_irq(&block->request_queue_lock);
2819 }
2820 
2821 static int dasd_open(struct block_device *bdev, fmode_t mode)
2822 {
2823  struct dasd_device *base;
2824  int rc;
2825 
2826  base = dasd_device_from_gendisk(bdev->bd_disk);
2827  if (!base)
2828  return -ENODEV;
2829 
2830  atomic_inc(&base->block->open_count);
2831  if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
2832  rc = -ENODEV;
2833  goto unlock;
2834  }
2835 
2836  if (!try_module_get(base->discipline->owner)) {
2837  rc = -EINVAL;
2838  goto unlock;
2839  }
2840 
2841  if (dasd_probeonly) {
2842  dev_info(&base->cdev->dev,
2843  "Accessing the DASD failed because it is in "
2844  "probeonly mode\n");
2845  rc = -EPERM;
2846  goto out;
2847  }
2848 
2849  if (base->state <= DASD_STATE_BASIC) {
2850  DBF_DEV_EVENT(DBF_ERR, base, " %s",
2851  " Cannot open unrecognized device");
2852  rc = -ENODEV;
2853  goto out;
2854  }
2855 
2856  if ((mode & FMODE_WRITE) &&
2857  (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) ||
2858  (base->features & DASD_FEATURE_READONLY))) {
2859  rc = -EROFS;
2860  goto out;
2861  }
2862 
2863  dasd_put_device(base);
2864  return 0;
2865 
2866 out:
2867  module_put(base->discipline->owner);
2868 unlock:
2869  atomic_dec(&base->block->open_count);
2870  dasd_put_device(base);
2871  return rc;
2872 }
2873 
2874 static int dasd_release(struct gendisk *disk, fmode_t mode)
2875 {
2876  struct dasd_device *base;
2877 
2878  base = dasd_device_from_gendisk(disk);
2879  if (!base)
2880  return -ENODEV;
2881 
2882  atomic_dec(&base->block->open_count);
2883  module_put(base->discipline->owner);
2884  dasd_put_device(base);
2885  return 0;
2886 }
2887 
2888 /*
2889  * Return disk geometry.
2890  */
2891 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
2892 {
2893  struct dasd_device *base;
2894 
2895  base = dasd_device_from_gendisk(bdev->bd_disk);
2896  if (!base)
2897  return -ENODEV;
2898 
2899  if (!base->discipline ||
2900  !base->discipline->fill_geometry) {
2901  dasd_put_device(base);
2902  return -EINVAL;
2903  }
2904  base->discipline->fill_geometry(base->block, geo);
2905  geo->start = get_start_sect(bdev) >> base->block->s2b_shift;
2906  dasd_put_device(base);
2907  return 0;
2908 }
2909 
2910 const struct block_device_operations
2912  .owner = THIS_MODULE,
2913  .open = dasd_open,
2914  .release = dasd_release,
2915  .ioctl = dasd_ioctl,
2916  .compat_ioctl = dasd_ioctl,
2917  .getgeo = dasd_getgeo,
2918 };
2919 
2920 /*******************************************************************************
2921  * end of block device operations
2922  */
2923 
2924 static void
2925 dasd_exit(void)
2926 {
2927 #ifdef CONFIG_PROC_FS
2928  dasd_proc_exit();
2929 #endif
2930  dasd_eer_exit();
2931  if (dasd_page_cache != NULL) {
2934  }
2936  dasd_devmap_exit();
2937  if (dasd_debug_area != NULL) {
2938  debug_unregister(dasd_debug_area);
2939  dasd_debug_area = NULL;
2940  }
2941  dasd_statistics_removeroot();
2942 }
2943 
2944 /*
2945  * SECTION: common functions for ccw_driver use
2946  */
2947 
2948 /*
2949  * Is the device read-only?
2950  * Note that this function does not report the setting of the
2951  * readonly device attribute, but how it is configured in z/VM.
2952  */
2953 int dasd_device_is_ro(struct dasd_device *device)
2954 {
2955  struct ccw_dev_id dev_id;
2956  struct diag210 diag_data;
2957  int rc;
2958 
2959  if (!MACHINE_IS_VM)
2960  return 0;
2961  ccw_device_get_id(device->cdev, &dev_id);
2962  memset(&diag_data, 0, sizeof(diag_data));
2963  diag_data.vrdcdvno = dev_id.devno;
2964  diag_data.vrdclen = sizeof(diag_data);
2965  rc = diag210(&diag_data);
2966  if (rc == 0 || rc == 2) {
2967  return diag_data.vrdcvfla & 0x80;
2968  } else {
2969  DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d",
2970  dev_id.devno, rc);
2971  return 0;
2972  }
2973 }
2975 
2976 static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
2977 {
2978  struct ccw_device *cdev = data;
2979  int ret;
2980 
2981  ret = ccw_device_set_online(cdev);
2982  if (ret)
2983  pr_warning("%s: Setting the DASD online failed with rc=%d\n",
2984  dev_name(&cdev->dev), ret);
2985 }
2986 
2987 /*
2988  * Initial attempt at a probe function. this can be simplified once
2989  * the other detection code is gone.
2990  */
2992  struct dasd_discipline *discipline)
2993 {
2994  int ret;
2995 
2996  ret = dasd_add_sysfs_files(cdev);
2997  if (ret) {
2998  DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s",
2999  "dasd_generic_probe: could not add "
3000  "sysfs entries");
3001  return ret;
3002  }
3003  cdev->handler = &dasd_int_handler;
3004 
3005  /*
3006  * Automatically online either all dasd devices (dasd_autodetect)
3007  * or all devices specified with dasd= parameters during
3008  * initial probe.
3009  */
3010  if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
3011  (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
3012  async_schedule(dasd_generic_auto_online, cdev);
3013  return 0;
3014 }
3015 
3016 /*
3017  * This will one day be called from a global not_oper handler.
3018  * It is also used by driver_unregister during module unload.
3019  */
3021 {
3022  struct dasd_device *device;
3023  struct dasd_block *block;
3024 
3025  cdev->handler = NULL;
3026 
3028  device = dasd_device_from_cdev(cdev);
3029  if (IS_ERR(device))
3030  return;
3031  if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3032  /* Already doing offline processing */
3033  dasd_put_device(device);
3034  return;
3035  }
3036  /*
3037  * This device is removed unconditionally. Set offline
3038  * flag to prevent dasd_open from opening it while it is
3039  * no quite down yet.
3040  */
3042  /* dasd_delete_device destroys the device reference. */
3043  block = device->block;
3044  dasd_delete_device(device);
3045  /*
3046  * life cycle of block is bound to device, so delete it after
3047  * device was safely removed
3048  */
3049  if (block)
3050  dasd_free_block(block);
3051 }
3052 
3053 /*
3054  * Activate a device. This is called from dasd_{eckd,fba}_probe() when either
3055  * the device is detected for the first time and is supposed to be used
3056  * or the user has started activation through sysfs.
3057  */
3059  struct dasd_discipline *base_discipline)
3060 {
3061  struct dasd_discipline *discipline;
3062  struct dasd_device *device;
3063  int rc;
3064 
3065  /* first online clears initial online feature flag */
3067  device = dasd_create_device(cdev);
3068  if (IS_ERR(device))
3069  return PTR_ERR(device);
3070 
3071  discipline = base_discipline;
3072  if (device->features & DASD_FEATURE_USEDIAG) {
3073  if (!dasd_diag_discipline_pointer) {
3074  pr_warning("%s Setting the DASD online failed because "
3075  "of missing DIAG discipline\n",
3076  dev_name(&cdev->dev));
3077  dasd_delete_device(device);
3078  return -ENODEV;
3079  }
3080  discipline = dasd_diag_discipline_pointer;
3081  }
3082  if (!try_module_get(base_discipline->owner)) {
3083  dasd_delete_device(device);
3084  return -EINVAL;
3085  }
3086  if (!try_module_get(discipline->owner)) {
3087  module_put(base_discipline->owner);
3088  dasd_delete_device(device);
3089  return -EINVAL;
3090  }
3091  device->base_discipline = base_discipline;
3092  device->discipline = discipline;
3093 
3094  /* check_device will allocate block device if necessary */
3095  rc = discipline->check_device(device);
3096  if (rc) {
3097  pr_warning("%s Setting the DASD online with discipline %s "
3098  "failed with rc=%i\n",
3099  dev_name(&cdev->dev), discipline->name, rc);
3100  module_put(discipline->owner);
3101  module_put(base_discipline->owner);
3102  dasd_delete_device(device);
3103  return rc;
3104  }
3105 
3107  if (device->state <= DASD_STATE_KNOWN) {
3108  pr_warning("%s Setting the DASD online failed because of a "
3109  "missing discipline\n", dev_name(&cdev->dev));
3110  rc = -ENODEV;
3112  if (device->block)
3113  dasd_free_block(device->block);
3114  dasd_delete_device(device);
3115  } else
3116  pr_debug("dasd_generic device %s found\n",
3117  dev_name(&cdev->dev));
3118 
3119  wait_event(dasd_init_waitq, _wait_for_device(device));
3120 
3121  dasd_put_device(device);
3122  return rc;
3123 }
3124 
3126 {
3127  struct dasd_device *device;
3128  struct dasd_block *block;
3129  int max_count, open_count;
3130 
3131  device = dasd_device_from_cdev(cdev);
3132  if (IS_ERR(device))
3133  return PTR_ERR(device);
3134  if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3135  /* Already doing offline processing */
3136  dasd_put_device(device);
3137  return 0;
3138  }
3139  /*
3140  * We must make sure that this device is currently not in use.
3141  * The open_count is increased for every opener, that includes
3142  * the blkdev_get in dasd_scan_partitions. We are only interested
3143  * in the other openers.
3144  */
3145  if (device->block) {
3146  max_count = device->block->bdev ? 0 : -1;
3147  open_count = atomic_read(&device->block->open_count);
3148  if (open_count > max_count) {
3149  if (open_count > 0)
3150  pr_warning("%s: The DASD cannot be set offline "
3151  "with open count %i\n",
3152  dev_name(&cdev->dev), open_count);
3153  else
3154  pr_warning("%s: The DASD cannot be set offline "
3155  "while it is in use\n",
3156  dev_name(&cdev->dev));
3157  clear_bit(DASD_FLAG_OFFLINE, &device->flags);
3158  dasd_put_device(device);
3159  return -EBUSY;
3160  }
3161  }
3163  /* dasd_delete_device destroys the device reference. */
3164  block = device->block;
3165  dasd_delete_device(device);
3166  /*
3167  * life cycle of block is bound to device, so delete it after
3168  * device was safely removed
3169  */
3170  if (block)
3171  dasd_free_block(block);
3172  return 0;
3173 }
3174 
3176 {
3177  struct dasd_ccw_req *cqr;
3178 
3179  dev_warn(&device->cdev->dev, "No operational channel path is left "
3180  "for the device\n");
3181  DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone");
3182  /* First of all call extended error reporting. */
3184 
3185  if (device->state < DASD_STATE_BASIC)
3186  return 0;
3187  /* Device is active. We want to keep it. */
3188  list_for_each_entry(cqr, &device->ccw_queue, devlist)
3189  if ((cqr->status == DASD_CQR_IN_IO) ||
3190  (cqr->status == DASD_CQR_CLEAR_PENDING)) {
3191  cqr->status = DASD_CQR_QUEUED;
3192  cqr->retries++;
3193  }
3195  dasd_device_clear_timer(device);
3196  dasd_schedule_device_bh(device);
3197  return 1;
3198 }
3200 
3202 {
3203  dev_info(&device->cdev->dev, "A channel path to the device has become "
3204  "operational\n");
3205  DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational");
3207  if (device->stopped & DASD_UNRESUMED_PM) {
3209  dasd_restore_device(device);
3210  return 1;
3211  }
3212  dasd_schedule_device_bh(device);
3213  if (device->block)
3214  dasd_schedule_block_bh(device->block);
3215  return 1;
3216 }
3218 
3219 int dasd_generic_notify(struct ccw_device *cdev, int event)
3220 {
3221  struct dasd_device *device;
3222  int ret;
3223 
3224  device = dasd_device_from_cdev_locked(cdev);
3225  if (IS_ERR(device))
3226  return 0;
3227  ret = 0;
3228  switch (event) {
3229  case CIO_GONE:
3230  case CIO_BOXED:
3231  case CIO_NO_PATH:
3232  device->path_data.opm = 0;
3233  device->path_data.ppm = 0;
3234  device->path_data.npm = 0;
3235  ret = dasd_generic_last_path_gone(device);
3236  break;
3237  case CIO_OPER:
3238  ret = 1;
3239  if (device->path_data.opm)
3240  ret = dasd_generic_path_operational(device);
3241  break;
3242  }
3243  dasd_put_device(device);
3244  return ret;
3245 }
3246 
3247 void dasd_generic_path_event(struct ccw_device *cdev, int *path_event)
3248 {
3249  int chp;
3250  __u8 oldopm, eventlpm;
3251  struct dasd_device *device;
3252 
3253  device = dasd_device_from_cdev_locked(cdev);
3254  if (IS_ERR(device))
3255  return;
3256  for (chp = 0; chp < 8; chp++) {
3257  eventlpm = 0x80 >> chp;
3258  if (path_event[chp] & PE_PATH_GONE) {
3259  oldopm = device->path_data.opm;
3260  device->path_data.opm &= ~eventlpm;
3261  device->path_data.ppm &= ~eventlpm;
3262  device->path_data.npm &= ~eventlpm;
3263  if (oldopm && !device->path_data.opm)
3265  }
3266  if (path_event[chp] & PE_PATH_AVAILABLE) {
3267  device->path_data.opm &= ~eventlpm;
3268  device->path_data.ppm &= ~eventlpm;
3269  device->path_data.npm &= ~eventlpm;
3270  device->path_data.tbvpm |= eventlpm;
3271  dasd_schedule_device_bh(device);
3272  }
3273  if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) {
3274  if (!(device->path_data.opm & eventlpm) &&
3275  !(device->path_data.tbvpm & eventlpm)) {
3276  /*
3277  * we can not establish a pathgroup on an
3278  * unavailable path, so trigger a path
3279  * verification first
3280  */
3281  device->path_data.tbvpm |= eventlpm;
3282  dasd_schedule_device_bh(device);
3283  }
3284  DBF_DEV_EVENT(DBF_WARNING, device, "%s",
3285  "Pathgroup re-established\n");
3286  if (device->discipline->kick_validate)
3287  device->discipline->kick_validate(device);
3288  }
3289  }
3290  dasd_put_device(device);
3291 }
3293 
3295 {
3296  if (!device->path_data.opm && lpm) {
3297  device->path_data.opm = lpm;
3299  } else
3300  device->path_data.opm |= lpm;
3301  return 0;
3302 }
3304 
3305 
3307 {
3308  struct dasd_ccw_req *cqr, *n;
3309  int rc;
3310  struct list_head freeze_queue;
3311  struct dasd_device *device = dasd_device_from_cdev(cdev);
3312 
3313  if (IS_ERR(device))
3314  return PTR_ERR(device);
3315 
3316  /* mark device as suspended */
3317  set_bit(DASD_FLAG_SUSPENDED, &device->flags);
3318 
3319  if (device->discipline->freeze)
3320  rc = device->discipline->freeze(device);
3321 
3322  /* disallow new I/O */
3324  /* clear active requests */
3325  INIT_LIST_HEAD(&freeze_queue);
3326  spin_lock_irq(get_ccwdev_lock(cdev));
3327  rc = 0;
3328  list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
3329  /* Check status and move request to flush_queue */
3330  if (cqr->status == DASD_CQR_IN_IO) {
3331  rc = device->discipline->term_IO(cqr);
3332  if (rc) {
3333  /* unable to terminate requeust */
3334  dev_err(&device->cdev->dev,
3335  "Unable to terminate request %p "
3336  "on suspend\n", cqr);
3337  spin_unlock_irq(get_ccwdev_lock(cdev));
3338  dasd_put_device(device);
3339  return rc;
3340  }
3341  }
3342  list_move_tail(&cqr->devlist, &freeze_queue);
3343  }
3344 
3345  spin_unlock_irq(get_ccwdev_lock(cdev));
3346 
3347  list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) {
3348  wait_event(dasd_flush_wq,
3349  (cqr->status != DASD_CQR_CLEAR_PENDING));
3350  if (cqr->status == DASD_CQR_CLEARED)
3351  cqr->status = DASD_CQR_QUEUED;
3352  }
3353  /* move freeze_queue to start of the ccw_queue */
3354  spin_lock_irq(get_ccwdev_lock(cdev));
3355  list_splice_tail(&freeze_queue, &device->ccw_queue);
3356  spin_unlock_irq(get_ccwdev_lock(cdev));
3357 
3358  dasd_put_device(device);
3359  return rc;
3360 }
3362 
3364 {
3365  struct dasd_device *device = dasd_device_from_cdev(cdev);
3366  int rc = 0;
3367 
3368  if (IS_ERR(device))
3369  return PTR_ERR(device);
3370 
3371  /* allow new IO again */
3374 
3375  dasd_schedule_device_bh(device);
3376 
3377  /*
3378  * call discipline restore function
3379  * if device is stopped do nothing e.g. for disconnected devices
3380  */
3381  if (device->discipline->restore && !(device->stopped))
3382  rc = device->discipline->restore(device);
3383  if (rc || device->stopped)
3384  /*
3385  * if the resume failed for the DASD we put it in
3386  * an UNRESUMED stop state
3387  */
3388  device->stopped |= DASD_UNRESUMED_PM;
3389 
3390  if (device->block)
3391  dasd_schedule_block_bh(device->block);
3392 
3393  clear_bit(DASD_FLAG_SUSPENDED, &device->flags);
3394  dasd_put_device(device);
3395  return 0;
3396 }
3398 
3399 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
3400  void *rdc_buffer,
3401  int rdc_buffer_size,
3402  int magic)
3403 {
3404  struct dasd_ccw_req *cqr;
3405  struct ccw1 *ccw;
3406  unsigned long *idaw;
3407 
3408  cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device);
3409 
3410  if (IS_ERR(cqr)) {
3411  /* internal error 13 - Allocating the RDC request failed*/
3412  dev_err(&device->cdev->dev,
3413  "An error occurred in the DASD device driver, "
3414  "reason=%s\n", "13");
3415  return cqr;
3416  }
3417 
3418  ccw = cqr->cpaddr;
3419  ccw->cmd_code = CCW_CMD_RDC;
3420  if (idal_is_needed(rdc_buffer, rdc_buffer_size)) {
3421  idaw = (unsigned long *) (cqr->data);
3422  ccw->cda = (__u32)(addr_t) idaw;
3423  ccw->flags = CCW_FLAG_IDA;
3424  idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size);
3425  } else {
3426  ccw->cda = (__u32)(addr_t) rdc_buffer;
3427  ccw->flags = 0;
3428  }
3429 
3430  ccw->count = rdc_buffer_size;
3431  cqr->startdev = device;
3432  cqr->memdev = device;
3433  cqr->expires = 10*HZ;
3434  cqr->retries = 256;
3435  cqr->buildclk = get_clock();
3436  cqr->status = DASD_CQR_FILLED;
3437  return cqr;
3438 }
3439 
3440 
3441 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
3442  void *rdc_buffer, int rdc_buffer_size)
3443 {
3444  int ret;
3445  struct dasd_ccw_req *cqr;
3446 
3447  cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size,
3448  magic);
3449  if (IS_ERR(cqr))
3450  return PTR_ERR(cqr);
3451 
3452  ret = dasd_sleep_on(cqr);
3453  dasd_sfree_request(cqr, cqr->memdev);
3454  return ret;
3455 }
3457 
3458 /*
3459  * In command mode and transport mode we need to look for sense
3460  * data in different places. The sense data itself is allways
3461  * an array of 32 bytes, so we can unify the sense data access
3462  * for both modes.
3463  */
3464 char *dasd_get_sense(struct irb *irb)
3465 {
3466  struct tsb *tsb = NULL;
3467  char *sense = NULL;
3468 
3469  if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
3470  if (irb->scsw.tm.tcw)
3471  tsb = tcw_get_tsb((struct tcw *)(unsigned long)
3472  irb->scsw.tm.tcw);
3473  if (tsb && tsb->length == 64 && tsb->flags)
3474  switch (tsb->flags & 0x07) {
3475  case 1: /* tsa_iostat */
3476  sense = tsb->tsa.iostat.sense;
3477  break;
3478  case 2: /* tsa_ddpc */
3479  sense = tsb->tsa.ddpc.sense;
3480  break;
3481  default:
3482  /* currently we don't use interrogate data */
3483  break;
3484  }
3485  } else if (irb->esw.esw0.erw.cons) {
3486  sense = irb->ecw;
3487  }
3488  return sense;
3489 }
3491 
3492 static inline int _wait_for_empty_queues(struct dasd_device *device)
3493 {
3494  if (device->block)
3495  return list_empty(&device->ccw_queue) &&
3496  list_empty(&device->block->ccw_queue);
3497  else
3498  return list_empty(&device->ccw_queue);
3499 }
3500 
3502 {
3503  struct dasd_device *device;
3504 
3505  device = dasd_device_from_cdev(cdev);
3506  if (IS_ERR(device))
3507  return;
3508 
3509  if (device->block)
3510  dasd_schedule_block_bh(device->block);
3511 
3512  dasd_schedule_device_bh(device);
3513 
3514  wait_event(shutdown_waitq, _wait_for_empty_queues(device));
3515 }
3517 
3518 static int __init dasd_init(void)
3519 {
3520  int rc;
3521 
3522  init_waitqueue_head(&dasd_init_waitq);
3523  init_waitqueue_head(&dasd_flush_wq);
3524  init_waitqueue_head(&generic_waitq);
3525  init_waitqueue_head(&shutdown_waitq);
3526 
3527  /* register 'common' DASD debug area, used for all DBF_XXX calls */
3528  dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
3529  if (dasd_debug_area == NULL) {
3530  rc = -ENOMEM;
3531  goto failed;
3532  }
3533  debug_register_view(dasd_debug_area, &debug_sprintf_view);
3534  debug_set_level(dasd_debug_area, DBF_WARNING);
3535 
3536  DBF_EVENT(DBF_EMERG, "%s", "debug area created");
3537 
3538  dasd_diag_discipline_pointer = NULL;
3539 
3540  dasd_statistics_createroot();
3541 
3542  rc = dasd_devmap_init();
3543  if (rc)
3544  goto failed;
3545  rc = dasd_gendisk_init();
3546  if (rc)
3547  goto failed;
3548  rc = dasd_parse();
3549  if (rc)
3550  goto failed;
3551  rc = dasd_eer_init();
3552  if (rc)
3553  goto failed;
3554 #ifdef CONFIG_PROC_FS
3555  rc = dasd_proc_init();
3556  if (rc)
3557  goto failed;
3558 #endif
3559 
3560  return 0;
3561 failed:
3562  pr_info("The DASD device driver could not be initialized\n");
3563  dasd_exit();
3564  return rc;
3565 }
3566 
3567 module_init(dasd_init);
3568 module_exit(dasd_exit);
3569 
3570 EXPORT_SYMBOL(dasd_debug_area);
3571 EXPORT_SYMBOL(dasd_diag_discipline_pointer);
3572 
3595