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1 /*
2 * File...........: linux/drivers/s390/block/dasd.c
3 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4 * Horst Hummel <Horst.Hummel@de.ibm.com>
5 * Carsten Otte <Cotte@de.ibm.com>
6 * Martin Schwidefsky <schwidefsky@de.ibm.com>
7 * Bugreports.to..: <Linux390@de.ibm.com>
8 * Copyright IBM Corp. 1999, 2009
9 */
10
11 #define KMSG_COMPONENT "dasd"
12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14 #include <linux/kmod.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/ctype.h>
18 #include <linux/major.h>
19 #include <linux/slab.h>
20 #include <linux/buffer_head.h>
21 #include <linux/hdreg.h>
22 #include <linux/async.h>
23
24 #include <asm/ccwdev.h>
25 #include <asm/ebcdic.h>
26 #include <asm/idals.h>
27 #include <asm/todclk.h>
28 #include <asm/itcw.h>
29
30 /* This is ugly... */
31 #define PRINTK_HEADER "dasd:"
32
33 #include "dasd_int.h"
34 /*
35 * SECTION: Constant definitions to be used within this file
36 */
37 #define DASD_CHANQ_MAX_SIZE 4
38
39 /*
40 * SECTION: exported variables of dasd.c
41 */
42 debug_info_t *dasd_debug_area;
43 struct dasd_discipline *dasd_diag_discipline_pointer;
44 void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
45
46 MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>");
47 MODULE_DESCRIPTION("Linux on S/390 DASD device driver,"
48 " Copyright 2000 IBM Corporation");
49 MODULE_SUPPORTED_DEVICE("dasd");
50 MODULE_LICENSE("GPL");
51
52 /*
53 * SECTION: prototypes for static functions of dasd.c
54 */
55 static int dasd_alloc_queue(struct dasd_block *);
56 static void dasd_setup_queue(struct dasd_block *);
57 static void dasd_free_queue(struct dasd_block *);
58 static void dasd_flush_request_queue(struct dasd_block *);
59 static int dasd_flush_block_queue(struct dasd_block *);
60 static void dasd_device_tasklet(struct dasd_device *);
61 static void dasd_block_tasklet(struct dasd_block *);
62 static void do_kick_device(struct work_struct *);
63 static void do_restore_device(struct work_struct *);
64 static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
65 static void dasd_device_timeout(unsigned long);
66 static void dasd_block_timeout(unsigned long);
67
68 /*
69 * SECTION: Operations on the device structure.
70 */
71 static wait_queue_head_t dasd_init_waitq;
72 static wait_queue_head_t dasd_flush_wq;
73 static wait_queue_head_t generic_waitq;
74
75 /*
76 * Allocate memory for a new device structure.
77 */
78 struct dasd_device *dasd_alloc_device(void)
79 {
80 struct dasd_device *device;
81
82 device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
83 if (!device)
84 return ERR_PTR(-ENOMEM);
85
86 /* Get two pages for normal block device operations. */
87 device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
88 if (!device->ccw_mem) {
89 kfree(device);
90 return ERR_PTR(-ENOMEM);
91 }
92 /* Get one page for error recovery. */
93 device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
94 if (!device->erp_mem) {
95 free_pages((unsigned long) device->ccw_mem, 1);
96 kfree(device);
97 return ERR_PTR(-ENOMEM);
98 }
99
100 dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
101 dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
102 spin_lock_init(&device->mem_lock);
103 atomic_set(&device->tasklet_scheduled, 0);
104 tasklet_init(&device->tasklet,
105 (void (*)(unsigned long)) dasd_device_tasklet,
106 (unsigned long) device);
107 INIT_LIST_HEAD(&device->ccw_queue);
108 init_timer(&device->timer);
109 device->timer.function = dasd_device_timeout;
110 device->timer.data = (unsigned long) device;
111 INIT_WORK(&device->kick_work, do_kick_device);
112 INIT_WORK(&device->restore_device, do_restore_device);
113 device->state = DASD_STATE_NEW;
114 device->target = DASD_STATE_NEW;
115
116 return device;
117 }
118
119 /*
120 * Free memory of a device structure.
121 */
122 void dasd_free_device(struct dasd_device *device)
123 {
124 kfree(device->private);
125 free_page((unsigned long) device->erp_mem);
126 free_pages((unsigned long) device->ccw_mem, 1);
127 kfree(device);
128 }
129
130 /*
131 * Allocate memory for a new device structure.
132 */
133 struct dasd_block *dasd_alloc_block(void)
134 {
135 struct dasd_block *block;
136
137 block = kzalloc(sizeof(*block), GFP_ATOMIC);
138 if (!block)
139 return ERR_PTR(-ENOMEM);
140 /* open_count = 0 means device online but not in use */
141 atomic_set(&block->open_count, -1);
142
143 spin_lock_init(&block->request_queue_lock);
144 atomic_set(&block->tasklet_scheduled, 0);
145 tasklet_init(&block->tasklet,
146 (void (*)(unsigned long)) dasd_block_tasklet,
147 (unsigned long) block);
148 INIT_LIST_HEAD(&block->ccw_queue);
149 spin_lock_init(&block->queue_lock);
150 init_timer(&block->timer);
151 block->timer.function = dasd_block_timeout;
152 block->timer.data = (unsigned long) block;
153
154 return block;
155 }
156
157 /*
158 * Free memory of a device structure.
159 */
160 void dasd_free_block(struct dasd_block *block)
161 {
162 kfree(block);
163 }
164
165 /*
166 * Make a new device known to the system.
167 */
168 static int dasd_state_new_to_known(struct dasd_device *device)
169 {
170 int rc;
171
172 /*
173 * As long as the device is not in state DASD_STATE_NEW we want to
174 * keep the reference count > 0.
175 */
176 dasd_get_device(device);
177
178 if (device->block) {
179 rc = dasd_alloc_queue(device->block);
180 if (rc) {
181 dasd_put_device(device);
182 return rc;
183 }
184 }
185 device->state = DASD_STATE_KNOWN;
186 return 0;
187 }
188
189 /*
190 * Let the system forget about a device.
191 */
192 static int dasd_state_known_to_new(struct dasd_device *device)
193 {
194 /* Disable extended error reporting for this device. */
195 dasd_eer_disable(device);
196 /* Forget the discipline information. */
197 if (device->discipline) {
198 if (device->discipline->uncheck_device)
199 device->discipline->uncheck_device(device);
200 module_put(device->discipline->owner);
201 }
202 device->discipline = NULL;
203 if (device->base_discipline)
204 module_put(device->base_discipline->owner);
205 device->base_discipline = NULL;
206 device->state = DASD_STATE_NEW;
207
208 if (device->block)
209 dasd_free_queue(device->block);
210
211 /* Give up reference we took in dasd_state_new_to_known. */
212 dasd_put_device(device);
213 return 0;
214 }
215
216 /*
217 * Request the irq line for the device.
218 */
219 static int dasd_state_known_to_basic(struct dasd_device *device)
220 {
221 int rc;
222
223 /* Allocate and register gendisk structure. */
224 if (device->block) {
225 rc = dasd_gendisk_alloc(device->block);
226 if (rc)
227 return rc;
228 }
229 /* register 'device' debug area, used for all DBF_DEV_XXX calls */
230 device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
231 8 * sizeof(long));
232 debug_register_view(device->debug_area, &debug_sprintf_view);
233 debug_set_level(device->debug_area, DBF_WARNING);
234 DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
235
236 device->state = DASD_STATE_BASIC;
237 return 0;
238 }
239
240 /*
241 * Release the irq line for the device. Terminate any running i/o.
242 */
243 static int dasd_state_basic_to_known(struct dasd_device *device)
244 {
245 int rc;
246 if (device->block) {
247 dasd_gendisk_free(device->block);
248 dasd_block_clear_timer(device->block);
249 }
250 rc = dasd_flush_device_queue(device);
251 if (rc)
252 return rc;
253 dasd_device_clear_timer(device);
254
255 DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
256 if (device->debug_area != NULL) {
257 debug_unregister(device->debug_area);
258 device->debug_area = NULL;
259 }
260 device->state = DASD_STATE_KNOWN;
261 return 0;
262 }
263
264 /*
265 * Do the initial analysis. The do_analysis function may return
266 * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
267 * until the discipline decides to continue the startup sequence
268 * by calling the function dasd_change_state. The eckd disciplines
269 * uses this to start a ccw that detects the format. The completion
270 * interrupt for this detection ccw uses the kernel event daemon to
271 * trigger the call to dasd_change_state. All this is done in the
272 * discipline code, see dasd_eckd.c.
273 * After the analysis ccw is done (do_analysis returned 0) the block
274 * device is setup.
275 * In case the analysis returns an error, the device setup is stopped
276 * (a fake disk was already added to allow formatting).
277 */
278 static int dasd_state_basic_to_ready(struct dasd_device *device)
279 {
280 int rc;
281 struct dasd_block *block;
282
283 rc = 0;
284 block = device->block;
285 /* make disk known with correct capacity */
286 if (block) {
287 if (block->base->discipline->do_analysis != NULL)
288 rc = block->base->discipline->do_analysis(block);
289 if (rc) {
290 if (rc != -EAGAIN)
291 device->state = DASD_STATE_UNFMT;
292 return rc;
293 }
294 dasd_setup_queue(block);
295 set_capacity(block->gdp,
296 block->blocks << block->s2b_shift);
297 device->state = DASD_STATE_READY;
298 rc = dasd_scan_partitions(block);
299 if (rc)
300 device->state = DASD_STATE_BASIC;
301 } else {
302 device->state = DASD_STATE_READY;
303 }
304 return rc;
305 }
306
307 /*
308 * Remove device from block device layer. Destroy dirty buffers.
309 * Forget format information. Check if the target level is basic
310 * and if it is create fake disk for formatting.
311 */
312 static int dasd_state_ready_to_basic(struct dasd_device *device)
313 {
314 int rc;
315
316 device->state = DASD_STATE_BASIC;
317 if (device->block) {
318 struct dasd_block *block = device->block;
319 rc = dasd_flush_block_queue(block);
320 if (rc) {
321 device->state = DASD_STATE_READY;
322 return rc;
323 }
324 dasd_destroy_partitions(block);
325 dasd_flush_request_queue(block);
326 block->blocks = 0;
327 block->bp_block = 0;
328 block->s2b_shift = 0;
329 }
330 return 0;
331 }
332
333 /*
334 * Back to basic.
335 */
336 static int dasd_state_unfmt_to_basic(struct dasd_device *device)
337 {
338 device->state = DASD_STATE_BASIC;
339 return 0;
340 }
341
342 /*
343 * Make the device online and schedule the bottom half to start
344 * the requeueing of requests from the linux request queue to the
345 * ccw queue.
346 */
347 static int
348 dasd_state_ready_to_online(struct dasd_device * device)
349 {
350 int rc;
351 struct gendisk *disk;
352 struct disk_part_iter piter;
353 struct hd_struct *part;
354
355 if (device->discipline->ready_to_online) {
356 rc = device->discipline->ready_to_online(device);
357 if (rc)
358 return rc;
359 }
360 device->state = DASD_STATE_ONLINE;
361 if (device->block) {
362 dasd_schedule_block_bh(device->block);
363 disk = device->block->bdev->bd_disk;
364 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
365 while ((part = disk_part_iter_next(&piter)))
366 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
367 disk_part_iter_exit(&piter);
368 }
369 return 0;
370 }
371
372 /*
373 * Stop the requeueing of requests again.
374 */
375 static int dasd_state_online_to_ready(struct dasd_device *device)
376 {
377 int rc;
378 struct gendisk *disk;
379 struct disk_part_iter piter;
380 struct hd_struct *part;
381
382 if (device->discipline->online_to_ready) {
383 rc = device->discipline->online_to_ready(device);
384 if (rc)
385 return rc;
386 }
387 device->state = DASD_STATE_READY;
388 if (device->block) {
389 disk = device->block->bdev->bd_disk;
390 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
391 while ((part = disk_part_iter_next(&piter)))
392 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
393 disk_part_iter_exit(&piter);
394 }
395 return 0;
396 }
397
398 /*
399 * Device startup state changes.
400 */
401 static int dasd_increase_state(struct dasd_device *device)
402 {
403 int rc;
404
405 rc = 0;
406 if (device->state == DASD_STATE_NEW &&
407 device->target >= DASD_STATE_KNOWN)
408 rc = dasd_state_new_to_known(device);
409
410 if (!rc &&
411 device->state == DASD_STATE_KNOWN &&
412 device->target >= DASD_STATE_BASIC)
413 rc = dasd_state_known_to_basic(device);
414
415 if (!rc &&
416 device->state == DASD_STATE_BASIC &&
417 device->target >= DASD_STATE_READY)
418 rc = dasd_state_basic_to_ready(device);
419
420 if (!rc &&
421 device->state == DASD_STATE_UNFMT &&
422 device->target > DASD_STATE_UNFMT)
423 rc = -EPERM;
424
425 if (!rc &&
426 device->state == DASD_STATE_READY &&
427 device->target >= DASD_STATE_ONLINE)
428 rc = dasd_state_ready_to_online(device);
429
430 return rc;
431 }
432
433 /*
434 * Device shutdown state changes.
435 */
436 static int dasd_decrease_state(struct dasd_device *device)
437 {
438 int rc;
439
440 rc = 0;
441 if (device->state == DASD_STATE_ONLINE &&
442 device->target <= DASD_STATE_READY)
443 rc = dasd_state_online_to_ready(device);
444
445 if (!rc &&
446 device->state == DASD_STATE_READY &&
447 device->target <= DASD_STATE_BASIC)
448 rc = dasd_state_ready_to_basic(device);
449
450 if (!rc &&
451 device->state == DASD_STATE_UNFMT &&
452 device->target <= DASD_STATE_BASIC)
453 rc = dasd_state_unfmt_to_basic(device);
454
455 if (!rc &&
456 device->state == DASD_STATE_BASIC &&
457 device->target <= DASD_STATE_KNOWN)
458 rc = dasd_state_basic_to_known(device);
459
460 if (!rc &&
461 device->state == DASD_STATE_KNOWN &&
462 device->target <= DASD_STATE_NEW)
463 rc = dasd_state_known_to_new(device);
464
465 return rc;
466 }
467
468 /*
469 * This is the main startup/shutdown routine.
470 */
471 static void dasd_change_state(struct dasd_device *device)
472 {
473 int rc;
474
475 if (device->state == device->target)
476 /* Already where we want to go today... */
477 return;
478 if (device->state < device->target)
479 rc = dasd_increase_state(device);
480 else
481 rc = dasd_decrease_state(device);
482 if (rc == -EAGAIN)
483 return;
484 if (rc)
485 device->target = device->state;
486
487 if (device->state == device->target) {
488 wake_up(&dasd_init_waitq);
489 dasd_put_device(device);
490 }
491
492 /* let user-space know that the device status changed */
493 kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
494 }
495
496 /*
497 * Kick starter for devices that did not complete the startup/shutdown
498 * procedure or were sleeping because of a pending state.
499 * dasd_kick_device will schedule a call do do_kick_device to the kernel
500 * event daemon.
501 */
502 static void do_kick_device(struct work_struct *work)
503 {
504 struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
505 dasd_change_state(device);
506 dasd_schedule_device_bh(device);
507 dasd_put_device(device);
508 }
509
510 void dasd_kick_device(struct dasd_device *device)
511 {
512 dasd_get_device(device);
513 /* queue call to dasd_kick_device to the kernel event daemon. */
514 schedule_work(&device->kick_work);
515 }
516
517 /*
518 * dasd_restore_device will schedule a call do do_restore_device to the kernel
519 * event daemon.
520 */
521 static void do_restore_device(struct work_struct *work)
522 {
523 struct dasd_device *device = container_of(work, struct dasd_device,
524 restore_device);
525 device->cdev->drv->restore(device->cdev);
526 dasd_put_device(device);
527 }
528
529 void dasd_restore_device(struct dasd_device *device)
530 {
531 dasd_get_device(device);
532 /* queue call to dasd_restore_device to the kernel event daemon. */
533 schedule_work(&device->restore_device);
534 }
535
536 /*
537 * Set the target state for a device and starts the state change.
538 */
539 void dasd_set_target_state(struct dasd_device *device, int target)
540 {
541 dasd_get_device(device);
542 /* If we are in probeonly mode stop at DASD_STATE_READY. */
543 if (dasd_probeonly && target > DASD_STATE_READY)
544 target = DASD_STATE_READY;
545 if (device->target != target) {
546 if (device->state == target) {
547 wake_up(&dasd_init_waitq);
548 dasd_put_device(device);
549 }
550 device->target = target;
551 }
552 if (device->state != device->target)
553 dasd_change_state(device);
554 }
555
556 /*
557 * Enable devices with device numbers in [from..to].
558 */
559 static inline int _wait_for_device(struct dasd_device *device)
560 {
561 return (device->state == device->target);
562 }
563
564 void dasd_enable_device(struct dasd_device *device)
565 {
566 dasd_set_target_state(device, DASD_STATE_ONLINE);
567 if (device->state <= DASD_STATE_KNOWN)
568 /* No discipline for device found. */
569 dasd_set_target_state(device, DASD_STATE_NEW);
570 /* Now wait for the devices to come up. */
571 wait_event(dasd_init_waitq, _wait_for_device(device));
572 }
573
574 /*
575 * SECTION: device operation (interrupt handler, start i/o, term i/o ...)
576 */
577 #ifdef CONFIG_DASD_PROFILE
578
579 struct dasd_profile_info_t dasd_global_profile;
580 unsigned int dasd_profile_level = DASD_PROFILE_OFF;
581
582 /*
583 * Increments counter in global and local profiling structures.
584 */
585 #define dasd_profile_counter(value, counter, block) \
586 { \
587 int index; \
588 for (index = 0; index < 31 && value >> (2+index); index++); \
589 dasd_global_profile.counter[index]++; \
590 block->profile.counter[index]++; \
591 }
592
593 /*
594 * Add profiling information for cqr before execution.
595 */
596 static void dasd_profile_start(struct dasd_block *block,
597 struct dasd_ccw_req *cqr,
598 struct request *req)
599 {
600 struct list_head *l;
601 unsigned int counter;
602
603 if (dasd_profile_level != DASD_PROFILE_ON)
604 return;
605
606 /* count the length of the chanq for statistics */
607 counter = 0;
608 list_for_each(l, &block->ccw_queue)
609 if (++counter >= 31)
610 break;
611 dasd_global_profile.dasd_io_nr_req[counter]++;
612 block->profile.dasd_io_nr_req[counter]++;
613 }
614
615 /*
616 * Add profiling information for cqr after execution.
617 */
618 static void dasd_profile_end(struct dasd_block *block,
619 struct dasd_ccw_req *cqr,
620 struct request *req)
621 {
622 long strtime, irqtime, endtime, tottime; /* in microseconds */
623 long tottimeps, sectors;
624
625 if (dasd_profile_level != DASD_PROFILE_ON)
626 return;
627
628 sectors = blk_rq_sectors(req);
629 if (!cqr->buildclk || !cqr->startclk ||
630 !cqr->stopclk || !cqr->endclk ||
631 !sectors)
632 return;
633
634 strtime = ((cqr->startclk - cqr->buildclk) >> 12);
635 irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
636 endtime = ((cqr->endclk - cqr->stopclk) >> 12);
637 tottime = ((cqr->endclk - cqr->buildclk) >> 12);
638 tottimeps = tottime / sectors;
639
640 if (!dasd_global_profile.dasd_io_reqs)
641 memset(&dasd_global_profile, 0,
642 sizeof(struct dasd_profile_info_t));
643 dasd_global_profile.dasd_io_reqs++;
644 dasd_global_profile.dasd_io_sects += sectors;
645
646 if (!block->profile.dasd_io_reqs)
647 memset(&block->profile, 0,
648 sizeof(struct dasd_profile_info_t));
649 block->profile.dasd_io_reqs++;
650 block->profile.dasd_io_sects += sectors;
651
652 dasd_profile_counter(sectors, dasd_io_secs, block);
653 dasd_profile_counter(tottime, dasd_io_times, block);
654 dasd_profile_counter(tottimeps, dasd_io_timps, block);
655 dasd_profile_counter(strtime, dasd_io_time1, block);
656 dasd_profile_counter(irqtime, dasd_io_time2, block);
657 dasd_profile_counter(irqtime / sectors, dasd_io_time2ps, block);
658 dasd_profile_counter(endtime, dasd_io_time3, block);
659 }
660 #else
661 #define dasd_profile_start(block, cqr, req) do {} while (0)
662 #define dasd_profile_end(block, cqr, req) do {} while (0)
663 #endif /* CONFIG_DASD_PROFILE */
664
665 /*
666 * Allocate memory for a channel program with 'cplength' channel
667 * command words and 'datasize' additional space. There are two
668 * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed
669 * memory and 2) dasd_smalloc_request uses the static ccw memory
670 * that gets allocated for each device.
671 */
672 struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength,
673 int datasize,
674 struct dasd_device *device)
675 {
676 struct dasd_ccw_req *cqr;
677
678 /* Sanity checks */
679 BUG_ON(datasize > PAGE_SIZE ||
680 (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
681
682 cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
683 if (cqr == NULL)
684 return ERR_PTR(-ENOMEM);
685 cqr->cpaddr = NULL;
686 if (cplength > 0) {
687 cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
688 GFP_ATOMIC | GFP_DMA);
689 if (cqr->cpaddr == NULL) {
690 kfree(cqr);
691 return ERR_PTR(-ENOMEM);
692 }
693 }
694 cqr->data = NULL;
695 if (datasize > 0) {
696 cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA);
697 if (cqr->data == NULL) {
698 kfree(cqr->cpaddr);
699 kfree(cqr);
700 return ERR_PTR(-ENOMEM);
701 }
702 }
703 cqr->magic = magic;
704 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
705 dasd_get_device(device);
706 return cqr;
707 }
708
709 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength,
710 int datasize,
711 struct dasd_device *device)
712 {
713 unsigned long flags;
714 struct dasd_ccw_req *cqr;
715 char *data;
716 int size;
717
718 /* Sanity checks */
719 BUG_ON(datasize > PAGE_SIZE ||
720 (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
721
722 size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
723 if (cplength > 0)
724 size += cplength * sizeof(struct ccw1);
725 if (datasize > 0)
726 size += datasize;
727 spin_lock_irqsave(&device->mem_lock, flags);
728 cqr = (struct dasd_ccw_req *)
729 dasd_alloc_chunk(&device->ccw_chunks, size);
730 spin_unlock_irqrestore(&device->mem_lock, flags);
731 if (cqr == NULL)
732 return ERR_PTR(-ENOMEM);
733 memset(cqr, 0, sizeof(struct dasd_ccw_req));
734 data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
735 cqr->cpaddr = NULL;
736 if (cplength > 0) {
737 cqr->cpaddr = (struct ccw1 *) data;
738 data += cplength*sizeof(struct ccw1);
739 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
740 }
741 cqr->data = NULL;
742 if (datasize > 0) {
743 cqr->data = data;
744 memset(cqr->data, 0, datasize);
745 }
746 cqr->magic = magic;
747 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
748 dasd_get_device(device);
749 return cqr;
750 }
751
752 /*
753 * Free memory of a channel program. This function needs to free all the
754 * idal lists that might have been created by dasd_set_cda and the
755 * struct dasd_ccw_req itself.
756 */
757 void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
758 {
759 #ifdef CONFIG_64BIT
760 struct ccw1 *ccw;
761
762 /* Clear any idals used for the request. */
763 ccw = cqr->cpaddr;
764 do {
765 clear_normalized_cda(ccw);
766 } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
767 #endif
768 kfree(cqr->cpaddr);
769 kfree(cqr->data);
770 kfree(cqr);
771 dasd_put_device(device);
772 }
773
774 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
775 {
776 unsigned long flags;
777
778 spin_lock_irqsave(&device->mem_lock, flags);
779 dasd_free_chunk(&device->ccw_chunks, cqr);
780 spin_unlock_irqrestore(&device->mem_lock, flags);
781 dasd_put_device(device);
782 }
783
784 /*
785 * Check discipline magic in cqr.
786 */
787 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
788 {
789 struct dasd_device *device;
790
791 if (cqr == NULL)
792 return -EINVAL;
793 device = cqr->startdev;
794 if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
795 DBF_DEV_EVENT(DBF_WARNING, device,
796 " dasd_ccw_req 0x%08x magic doesn't match"
797 " discipline 0x%08x",
798 cqr->magic,
799 *(unsigned int *) device->discipline->name);
800 return -EINVAL;
801 }
802 return 0;
803 }
804
805 /*
806 * Terminate the current i/o and set the request to clear_pending.
807 * Timer keeps device runnig.
808 * ccw_device_clear can fail if the i/o subsystem
809 * is in a bad mood.
810 */
811 int dasd_term_IO(struct dasd_ccw_req *cqr)
812 {
813 struct dasd_device *device;
814 int retries, rc;
815 char errorstring[ERRORLENGTH];
816
817 /* Check the cqr */
818 rc = dasd_check_cqr(cqr);
819 if (rc)
820 return rc;
821 retries = 0;
822 device = (struct dasd_device *) cqr->startdev;
823 while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
824 rc = ccw_device_clear(device->cdev, (long) cqr);
825 switch (rc) {
826 case 0: /* termination successful */
827 cqr->retries--;
828 cqr->status = DASD_CQR_CLEAR_PENDING;
829 cqr->stopclk = get_clock();
830 cqr->starttime = 0;
831 DBF_DEV_EVENT(DBF_DEBUG, device,
832 "terminate cqr %p successful",
833 cqr);
834 break;
835 case -ENODEV:
836 DBF_DEV_EVENT(DBF_ERR, device, "%s",
837 "device gone, retry");
838 break;
839 case -EIO:
840 DBF_DEV_EVENT(DBF_ERR, device, "%s",
841 "I/O error, retry");
842 break;
843 case -EINVAL:
844 case -EBUSY:
845 DBF_DEV_EVENT(DBF_ERR, device, "%s",
846 "device busy, retry later");
847 break;
848 default:
849 /* internal error 10 - unknown rc*/
850 snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
851 dev_err(&device->cdev->dev, "An error occurred in the "
852 "DASD device driver, reason=%s\n", errorstring);
853 BUG();
854 break;
855 }
856 retries++;
857 }
858 dasd_schedule_device_bh(device);
859 return rc;
860 }
861
862 /*
863 * Start the i/o. This start_IO can fail if the channel is really busy.
864 * In that case set up a timer to start the request later.
865 */
866 int dasd_start_IO(struct dasd_ccw_req *cqr)
867 {
868 struct dasd_device *device;
869 int rc;
870 char errorstring[ERRORLENGTH];
871
872 /* Check the cqr */
873 rc = dasd_check_cqr(cqr);
874 if (rc) {
875 cqr->intrc = rc;
876 return rc;
877 }
878 device = (struct dasd_device *) cqr->startdev;
879 if (cqr->retries < 0) {
880 /* internal error 14 - start_IO run out of retries */
881 sprintf(errorstring, "14 %p", cqr);
882 dev_err(&device->cdev->dev, "An error occurred in the DASD "
883 "device driver, reason=%s\n", errorstring);
884 cqr->status = DASD_CQR_ERROR;
885 return -EIO;
886 }
887 cqr->startclk = get_clock();
888 cqr->starttime = jiffies;
889 cqr->retries--;
890 if (cqr->cpmode == 1) {
891 rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
892 (long) cqr, cqr->lpm);
893 } else {
894 rc = ccw_device_start(device->cdev, cqr->cpaddr,
895 (long) cqr, cqr->lpm, 0);
896 }
897 switch (rc) {
898 case 0:
899 cqr->status = DASD_CQR_IN_IO;
900 break;
901 case -EBUSY:
902 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
903 "start_IO: device busy, retry later");
904 break;
905 case -ETIMEDOUT:
906 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
907 "start_IO: request timeout, retry later");
908 break;
909 case -EACCES:
910 /* -EACCES indicates that the request used only a
911 * subset of the available pathes and all these
912 * pathes are gone.
913 * Do a retry with all available pathes.
914 */
915 cqr->lpm = LPM_ANYPATH;
916 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
917 "start_IO: selected pathes gone,"
918 " retry on all pathes");
919 break;
920 case -ENODEV:
921 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
922 "start_IO: -ENODEV device gone, retry");
923 break;
924 case -EIO:
925 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
926 "start_IO: -EIO device gone, retry");
927 break;
928 case -EINVAL:
929 /* most likely caused in power management context */
930 DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
931 "start_IO: -EINVAL device currently "
932 "not accessible");
933 break;
934 default:
935 /* internal error 11 - unknown rc */
936 snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
937 dev_err(&device->cdev->dev,
938 "An error occurred in the DASD device driver, "
939 "reason=%s\n", errorstring);
940 BUG();
941 break;
942 }
943 cqr->intrc = rc;
944 return rc;
945 }
946
947 /*
948 * Timeout function for dasd devices. This is used for different purposes
949 * 1) missing interrupt handler for normal operation
950 * 2) delayed start of request where start_IO failed with -EBUSY
951 * 3) timeout for missing state change interrupts
952 * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
953 * DASD_CQR_QUEUED for 2) and 3).
954 */
955 static void dasd_device_timeout(unsigned long ptr)
956 {
957 unsigned long flags;
958 struct dasd_device *device;
959
960 device = (struct dasd_device *) ptr;
961 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
962 /* re-activate request queue */
963 device->stopped &= ~DASD_STOPPED_PENDING;
964 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
965 dasd_schedule_device_bh(device);
966 }
967
968 /*
969 * Setup timeout for a device in jiffies.
970 */
971 void dasd_device_set_timer(struct dasd_device *device, int expires)
972 {
973 if (expires == 0)
974 del_timer(&device->timer);
975 else
976 mod_timer(&device->timer, jiffies + expires);
977 }
978
979 /*
980 * Clear timeout for a device.
981 */
982 void dasd_device_clear_timer(struct dasd_device *device)
983 {
984 del_timer(&device->timer);
985 }
986
987 static void dasd_handle_killed_request(struct ccw_device *cdev,
988 unsigned long intparm)
989 {
990 struct dasd_ccw_req *cqr;
991 struct dasd_device *device;
992
993 if (!intparm)
994 return;
995 cqr = (struct dasd_ccw_req *) intparm;
996 if (cqr->status != DASD_CQR_IN_IO) {
997 DBF_EVENT(DBF_DEBUG,
998 "invalid status in handle_killed_request: "
999 "bus_id %s, status %02x",
1000 dev_name(&cdev->dev), cqr->status);
1001 return;
1002 }
1003
1004 device = (struct dasd_device *) cqr->startdev;
1005 if (device == NULL ||
1006 device != dasd_device_from_cdev_locked(cdev) ||
1007 strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
1008 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid device in request: "
1009 "bus_id %s", dev_name(&cdev->dev));
1010 return;
1011 }
1012
1013 /* Schedule request to be retried. */
1014 cqr->status = DASD_CQR_QUEUED;
1015
1016 dasd_device_clear_timer(device);
1017 dasd_schedule_device_bh(device);
1018 dasd_put_device(device);
1019 }
1020
1021 void dasd_generic_handle_state_change(struct dasd_device *device)
1022 {
1023 /* First of all start sense subsystem status request. */
1024 dasd_eer_snss(device);
1025
1026 device->stopped &= ~DASD_STOPPED_PENDING;
1027 dasd_schedule_device_bh(device);
1028 if (device->block)
1029 dasd_schedule_block_bh(device->block);
1030 }
1031
1032 /*
1033 * Interrupt handler for "normal" ssch-io based dasd devices.
1034 */
1035 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
1036 struct irb *irb)
1037 {
1038 struct dasd_ccw_req *cqr, *next;
1039 struct dasd_device *device;
1040 unsigned long long now;
1041 int expires;
1042
1043 if (IS_ERR(irb)) {
1044 switch (PTR_ERR(irb)) {
1045 case -EIO:
1046 break;
1047 case -ETIMEDOUT:
1048 DBF_EVENT(DBF_WARNING, "%s(%s): request timed out\n",
1049 __func__, dev_name(&cdev->dev));
1050 break;
1051 default:
1052 DBF_EVENT(DBF_WARNING, "%s(%s): unknown error %ld\n",
1053 __func__, dev_name(&cdev->dev), PTR_ERR(irb));
1054 }
1055 dasd_handle_killed_request(cdev, intparm);
1056 return;
1057 }
1058
1059 now = get_clock();
1060
1061 /* check for unsolicited interrupts */
1062 cqr = (struct dasd_ccw_req *) intparm;
1063 if (!cqr || ((scsw_cc(&irb->scsw) == 1) &&
1064 (scsw_fctl(&irb->scsw) & SCSW_FCTL_START_FUNC) &&
1065 (scsw_stctl(&irb->scsw) & SCSW_STCTL_STATUS_PEND))) {
1066 if (cqr && cqr->status == DASD_CQR_IN_IO)
1067 cqr->status = DASD_CQR_QUEUED;
1068 device = dasd_device_from_cdev_locked(cdev);
1069 if (!IS_ERR(device)) {
1070 dasd_device_clear_timer(device);
1071 device->discipline->handle_unsolicited_interrupt(device,
1072 irb);
1073 dasd_put_device(device);
1074 }
1075 return;
1076 }
1077
1078 device = (struct dasd_device *) cqr->startdev;
1079 if (!device ||
1080 strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
1081 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid device in request: "
1082 "bus_id %s", dev_name(&cdev->dev));
1083 return;
1084 }
1085
1086 /* Check for clear pending */
1087 if (cqr->status == DASD_CQR_CLEAR_PENDING &&
1088 scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
1089 cqr->status = DASD_CQR_CLEARED;
1090 dasd_device_clear_timer(device);
1091 wake_up(&dasd_flush_wq);
1092 dasd_schedule_device_bh(device);
1093 return;
1094 }
1095
1096 /* check status - the request might have been killed by dyn detach */
1097 if (cqr->status != DASD_CQR_IN_IO) {
1098 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
1099 "status %02x", dev_name(&cdev->dev), cqr->status);
1100 return;
1101 }
1102
1103 next = NULL;
1104 expires = 0;
1105 if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1106 scsw_cstat(&irb->scsw) == 0) {
1107 /* request was completed successfully */
1108 cqr->status = DASD_CQR_SUCCESS;
1109 cqr->stopclk = now;
1110 /* Start first request on queue if possible -> fast_io. */
1111 if (cqr->devlist.next != &device->ccw_queue) {
1112 next = list_entry(cqr->devlist.next,
1113 struct dasd_ccw_req, devlist);
1114 }
1115 } else { /* error */
1116 memcpy(&cqr->irb, irb, sizeof(struct irb));
1117 /* log sense for every failed I/O to s390 debugfeature */
1118 dasd_log_sense_dbf(cqr, irb);
1119 if (device->features & DASD_FEATURE_ERPLOG) {
1120 dasd_log_sense(cqr, irb);
1121 }
1122
1123 /*
1124 * If we don't want complex ERP for this request, then just
1125 * reset this and retry it in the fastpath
1126 */
1127 if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
1128 cqr->retries > 0) {
1129 if (cqr->lpm == LPM_ANYPATH)
1130 DBF_DEV_EVENT(DBF_DEBUG, device,
1131 "default ERP in fastpath "
1132 "(%i retries left)",
1133 cqr->retries);
1134 cqr->lpm = LPM_ANYPATH;
1135 cqr->status = DASD_CQR_QUEUED;
1136 next = cqr;
1137 } else
1138 cqr->status = DASD_CQR_ERROR;
1139 }
1140 if (next && (next->status == DASD_CQR_QUEUED) &&
1141 (!device->stopped)) {
1142 if (device->discipline->start_IO(next) == 0)
1143 expires = next->expires;
1144 }
1145 if (expires != 0)
1146 dasd_device_set_timer(device, expires);
1147 else
1148 dasd_device_clear_timer(device);
1149 dasd_schedule_device_bh(device);
1150 }
1151
1152 /*
1153 * If we have an error on a dasd_block layer request then we cancel
1154 * and return all further requests from the same dasd_block as well.
1155 */
1156 static void __dasd_device_recovery(struct dasd_device *device,
1157 struct dasd_ccw_req *ref_cqr)
1158 {
1159 struct list_head *l, *n;
1160 struct dasd_ccw_req *cqr;
1161
1162 /*
1163 * only requeue request that came from the dasd_block layer
1164 */
1165 if (!ref_cqr->block)
1166 return;
1167
1168 list_for_each_safe(l, n, &device->ccw_queue) {
1169 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1170 if (cqr->status == DASD_CQR_QUEUED &&
1171 ref_cqr->block == cqr->block) {
1172 cqr->status = DASD_CQR_CLEARED;
1173 }
1174 }
1175 };
1176
1177 /*
1178 * Remove those ccw requests from the queue that need to be returned
1179 * to the upper layer.
1180 */
1181 static void __dasd_device_process_ccw_queue(struct dasd_device *device,
1182 struct list_head *final_queue)
1183 {
1184 struct list_head *l, *n;
1185 struct dasd_ccw_req *cqr;
1186
1187 /* Process request with final status. */
1188 list_for_each_safe(l, n, &device->ccw_queue) {
1189 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1190
1191 /* Stop list processing at the first non-final request. */
1192 if (cqr->status == DASD_CQR_QUEUED ||
1193 cqr->status == DASD_CQR_IN_IO ||
1194 cqr->status == DASD_CQR_CLEAR_PENDING)
1195 break;
1196 if (cqr->status == DASD_CQR_ERROR) {
1197 __dasd_device_recovery(device, cqr);
1198 }
1199 /* Rechain finished requests to final queue */
1200 list_move_tail(&cqr->devlist, final_queue);
1201 }
1202 }
1203
1204 /*
1205 * the cqrs from the final queue are returned to the upper layer
1206 * by setting a dasd_block state and calling the callback function
1207 */
1208 static void __dasd_device_process_final_queue(struct dasd_device *device,
1209 struct list_head *final_queue)
1210 {
1211 struct list_head *l, *n;
1212 struct dasd_ccw_req *cqr;
1213 struct dasd_block *block;
1214 void (*callback)(struct dasd_ccw_req *, void *data);
1215 void *callback_data;
1216 char errorstring[ERRORLENGTH];
1217
1218 list_for_each_safe(l, n, final_queue) {
1219 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1220 list_del_init(&cqr->devlist);
1221 block = cqr->block;
1222 callback = cqr->callback;
1223 callback_data = cqr->callback_data;
1224 if (block)
1225 spin_lock_bh(&block->queue_lock);
1226 switch (cqr->status) {
1227 case DASD_CQR_SUCCESS:
1228 cqr->status = DASD_CQR_DONE;
1229 break;
1230 case DASD_CQR_ERROR:
1231 cqr->status = DASD_CQR_NEED_ERP;
1232 break;
1233 case DASD_CQR_CLEARED:
1234 cqr->status = DASD_CQR_TERMINATED;
1235 break;
1236 default:
1237 /* internal error 12 - wrong cqr status*/
1238 snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
1239 dev_err(&device->cdev->dev,
1240 "An error occurred in the DASD device driver, "
1241 "reason=%s\n", errorstring);
1242 BUG();
1243 }
1244 if (cqr->callback != NULL)
1245 (callback)(cqr, callback_data);
1246 if (block)
1247 spin_unlock_bh(&block->queue_lock);
1248 }
1249 }
1250
1251 /*
1252 * Take a look at the first request on the ccw queue and check
1253 * if it reached its expire time. If so, terminate the IO.
1254 */
1255 static void __dasd_device_check_expire(struct dasd_device *device)
1256 {
1257 struct dasd_ccw_req *cqr;
1258
1259 if (list_empty(&device->ccw_queue))
1260 return;
1261 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1262 if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
1263 (time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
1264 if (device->discipline->term_IO(cqr) != 0) {
1265 /* Hmpf, try again in 5 sec */
1266 dev_err(&device->cdev->dev,
1267 "cqr %p timed out (%is) but cannot be "
1268 "ended, retrying in 5 s\n",
1269 cqr, (cqr->expires/HZ));
1270 cqr->expires += 5*HZ;
1271 dasd_device_set_timer(device, 5*HZ);
1272 } else {
1273 dev_err(&device->cdev->dev,
1274 "cqr %p timed out (%is), %i retries "
1275 "remaining\n", cqr, (cqr->expires/HZ),
1276 cqr->retries);
1277 }
1278 }
1279 }
1280
1281 /*
1282 * Take a look at the first request on the ccw queue and check
1283 * if it needs to be started.
1284 */
1285 static void __dasd_device_start_head(struct dasd_device *device)
1286 {
1287 struct dasd_ccw_req *cqr;
1288 int rc;
1289
1290 if (list_empty(&device->ccw_queue))
1291 return;
1292 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1293 if (cqr->status != DASD_CQR_QUEUED)
1294 return;
1295 /* when device is stopped, return request to previous layer */
1296 if (device->stopped) {
1297 cqr->status = DASD_CQR_CLEARED;
1298 dasd_schedule_device_bh(device);
1299 return;
1300 }
1301
1302 rc = device->discipline->start_IO(cqr);
1303 if (rc == 0)
1304 dasd_device_set_timer(device, cqr->expires);
1305 else if (rc == -EACCES) {
1306 dasd_schedule_device_bh(device);
1307 } else
1308 /* Hmpf, try again in 1/2 sec */
1309 dasd_device_set_timer(device, 50);
1310 }
1311
1312 /*
1313 * Go through all request on the dasd_device request queue,
1314 * terminate them on the cdev if necessary, and return them to the
1315 * submitting layer via callback.
1316 * Note:
1317 * Make sure that all 'submitting layers' still exist when
1318 * this function is called!. In other words, when 'device' is a base
1319 * device then all block layer requests must have been removed before
1320 * via dasd_flush_block_queue.
1321 */
1322 int dasd_flush_device_queue(struct dasd_device *device)
1323 {
1324 struct dasd_ccw_req *cqr, *n;
1325 int rc;
1326 struct list_head flush_queue;
1327
1328 INIT_LIST_HEAD(&flush_queue);
1329 spin_lock_irq(get_ccwdev_lock(device->cdev));
1330 rc = 0;
1331 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
1332 /* Check status and move request to flush_queue */
1333 switch (cqr->status) {
1334 case DASD_CQR_IN_IO:
1335 rc = device->discipline->term_IO(cqr);
1336 if (rc) {
1337 /* unable to terminate requeust */
1338 dev_err(&device->cdev->dev,
1339 "Flushing the DASD request queue "
1340 "failed for request %p\n", cqr);
1341 /* stop flush processing */
1342 goto finished;
1343 }
1344 break;
1345 case DASD_CQR_QUEUED:
1346 cqr->stopclk = get_clock();
1347 cqr->status = DASD_CQR_CLEARED;
1348 break;
1349 default: /* no need to modify the others */
1350 break;
1351 }
1352 list_move_tail(&cqr->devlist, &flush_queue);
1353 }
1354 finished:
1355 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1356 /*
1357 * After this point all requests must be in state CLEAR_PENDING,
1358 * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
1359 * one of the others.
1360 */
1361 list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
1362 wait_event(dasd_flush_wq,
1363 (cqr->status != DASD_CQR_CLEAR_PENDING));
1364 /*
1365 * Now set each request back to TERMINATED, DONE or NEED_ERP
1366 * and call the callback function of flushed requests
1367 */
1368 __dasd_device_process_final_queue(device, &flush_queue);
1369 return rc;
1370 }
1371
1372 /*
1373 * Acquire the device lock and process queues for the device.
1374 */
1375 static void dasd_device_tasklet(struct dasd_device *device)
1376 {
1377 struct list_head final_queue;
1378
1379 atomic_set (&device->tasklet_scheduled, 0);
1380 INIT_LIST_HEAD(&final_queue);
1381 spin_lock_irq(get_ccwdev_lock(device->cdev));
1382 /* Check expire time of first request on the ccw queue. */
1383 __dasd_device_check_expire(device);
1384 /* find final requests on ccw queue */
1385 __dasd_device_process_ccw_queue(device, &final_queue);
1386 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1387 /* Now call the callback function of requests with final status */
1388 __dasd_device_process_final_queue(device, &final_queue);
1389 spin_lock_irq(get_ccwdev_lock(device->cdev));
1390 /* Now check if the head of the ccw queue needs to be started. */
1391 __dasd_device_start_head(device);
1392 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1393 dasd_put_device(device);
1394 }
1395
1396 /*
1397 * Schedules a call to dasd_tasklet over the device tasklet.
1398 */
1399 void dasd_schedule_device_bh(struct dasd_device *device)
1400 {
1401 /* Protect against rescheduling. */
1402 if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
1403 return;
1404 dasd_get_device(device);
1405 tasklet_hi_schedule(&device->tasklet);
1406 }
1407
1408 /*
1409 * Queue a request to the head of the device ccw_queue.
1410 * Start the I/O if possible.
1411 */
1412 void dasd_add_request_head(struct dasd_ccw_req *cqr)
1413 {
1414 struct dasd_device *device;
1415 unsigned long flags;
1416
1417 device = cqr->startdev;
1418 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1419 cqr->status = DASD_CQR_QUEUED;
1420 list_add(&cqr->devlist, &device->ccw_queue);
1421 /* let the bh start the request to keep them in order */
1422 dasd_schedule_device_bh(device);
1423 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1424 }
1425
1426 /*
1427 * Queue a request to the tail of the device ccw_queue.
1428 * Start the I/O if possible.
1429 */
1430 void dasd_add_request_tail(struct dasd_ccw_req *cqr)
1431 {
1432 struct dasd_device *device;
1433 unsigned long flags;
1434
1435 device = cqr->startdev;
1436 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1437 cqr->status = DASD_CQR_QUEUED;
1438 list_add_tail(&cqr->devlist, &device->ccw_queue);
1439 /* let the bh start the request to keep them in order */
1440 dasd_schedule_device_bh(device);
1441 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1442 }
1443
1444 /*
1445 * Wakeup helper for the 'sleep_on' functions.
1446 */
1447 static void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
1448 {
1449 wake_up((wait_queue_head_t *) data);
1450 }
1451
1452 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
1453 {
1454 struct dasd_device *device;
1455 int rc;
1456
1457 device = cqr->startdev;
1458 spin_lock_irq(get_ccwdev_lock(device->cdev));
1459 rc = ((cqr->status == DASD_CQR_DONE ||
1460 cqr->status == DASD_CQR_NEED_ERP ||
1461 cqr->status == DASD_CQR_TERMINATED) &&
1462 list_empty(&cqr->devlist));
1463 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1464 return rc;
1465 }
1466
1467 /*
1468 * Queue a request to the tail of the device ccw_queue and wait for
1469 * it's completion.
1470 */
1471 int dasd_sleep_on(struct dasd_ccw_req *cqr)
1472 {
1473 struct dasd_device *device;
1474 int rc;
1475
1476 device = cqr->startdev;
1477
1478 cqr->callback = dasd_wakeup_cb;
1479 cqr->callback_data = (void *) &generic_waitq;
1480 dasd_add_request_tail(cqr);
1481 wait_event(generic_waitq, _wait_for_wakeup(cqr));
1482
1483 if (cqr->status == DASD_CQR_DONE)
1484 rc = 0;
1485 else if (cqr->intrc)
1486 rc = cqr->intrc;
1487 else
1488 rc = -EIO;
1489 return rc;
1490 }
1491
1492 /*
1493 * Queue a request to the tail of the device ccw_queue and wait
1494 * interruptible for it's completion.
1495 */
1496 int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
1497 {
1498 struct dasd_device *device;
1499 int rc;
1500
1501 device = cqr->startdev;
1502 cqr->callback = dasd_wakeup_cb;
1503 cqr->callback_data = (void *) &generic_waitq;
1504 dasd_add_request_tail(cqr);
1505 rc = wait_event_interruptible(generic_waitq, _wait_for_wakeup(cqr));
1506 if (rc == -ERESTARTSYS) {
1507 dasd_cancel_req(cqr);
1508 /* wait (non-interruptible) for final status */
1509 wait_event(generic_waitq, _wait_for_wakeup(cqr));
1510 cqr->intrc = rc;
1511 }
1512
1513 if (cqr->status == DASD_CQR_DONE)
1514 rc = 0;
1515 else if (cqr->intrc)
1516 rc = cqr->intrc;
1517 else
1518 rc = -EIO;
1519 return rc;
1520 }
1521
1522 /*
1523 * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
1524 * for eckd devices) the currently running request has to be terminated
1525 * and be put back to status queued, before the special request is added
1526 * to the head of the queue. Then the special request is waited on normally.
1527 */
1528 static inline int _dasd_term_running_cqr(struct dasd_device *device)
1529 {
1530 struct dasd_ccw_req *cqr;
1531
1532 if (list_empty(&device->ccw_queue))
1533 return 0;
1534 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1535 return device->discipline->term_IO(cqr);
1536 }
1537
1538 int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
1539 {
1540 struct dasd_device *device;
1541 int rc;
1542
1543 device = cqr->startdev;
1544 spin_lock_irq(get_ccwdev_lock(device->cdev));
1545 rc = _dasd_term_running_cqr(device);
1546 if (rc) {
1547 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1548 return rc;
1549 }
1550
1551 cqr->callback = dasd_wakeup_cb;
1552 cqr->callback_data = (void *) &generic_waitq;
1553 cqr->status = DASD_CQR_QUEUED;
1554 list_add(&cqr->devlist, &device->ccw_queue);
1555
1556 /* let the bh start the request to keep them in order */
1557 dasd_schedule_device_bh(device);
1558
1559 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1560
1561 wait_event(generic_waitq, _wait_for_wakeup(cqr));
1562
1563 if (cqr->status == DASD_CQR_DONE)
1564 rc = 0;
1565 else if (cqr->intrc)
1566 rc = cqr->intrc;
1567 else
1568 rc = -EIO;
1569 return rc;
1570 }
1571
1572 /*
1573 * Cancels a request that was started with dasd_sleep_on_req.
1574 * This is useful to timeout requests. The request will be
1575 * terminated if it is currently in i/o.
1576 * Returns 1 if the request has been terminated.
1577 * 0 if there was no need to terminate the request (not started yet)
1578 * negative error code if termination failed
1579 * Cancellation of a request is an asynchronous operation! The calling
1580 * function has to wait until the request is properly returned via callback.
1581 */
1582 int dasd_cancel_req(struct dasd_ccw_req *cqr)
1583 {
1584 struct dasd_device *device = cqr->startdev;
1585 unsigned long flags;
1586 int rc;
1587
1588 rc = 0;
1589 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1590 switch (cqr->status) {
1591 case DASD_CQR_QUEUED:
1592 /* request was not started - just set to cleared */
1593 cqr->status = DASD_CQR_CLEARED;
1594 break;
1595 case DASD_CQR_IN_IO:
1596 /* request in IO - terminate IO and release again */
1597 rc = device->discipline->term_IO(cqr);
1598 if (rc) {
1599 dev_err(&device->cdev->dev,
1600 "Cancelling request %p failed with rc=%d\n",
1601 cqr, rc);
1602 } else {
1603 cqr->stopclk = get_clock();
1604 rc = 1;
1605 }
1606 break;
1607 default: /* already finished or clear pending - do nothing */
1608 break;
1609 }
1610 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1611 dasd_schedule_device_bh(device);
1612 return rc;
1613 }
1614
1615
1616 /*
1617 * SECTION: Operations of the dasd_block layer.
1618 */
1619
1620 /*
1621 * Timeout function for dasd_block. This is used when the block layer
1622 * is waiting for something that may not come reliably, (e.g. a state
1623 * change interrupt)
1624 */
1625 static void dasd_block_timeout(unsigned long ptr)
1626 {
1627 unsigned long flags;
1628 struct dasd_block *block;
1629
1630 block = (struct dasd_block *) ptr;
1631 spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
1632 /* re-activate request queue */
1633 block->base->stopped &= ~DASD_STOPPED_PENDING;
1634 spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
1635 dasd_schedule_block_bh(block);
1636 }
1637
1638 /*
1639 * Setup timeout for a dasd_block in jiffies.
1640 */
1641 void dasd_block_set_timer(struct dasd_block *block, int expires)
1642 {
1643 if (expires == 0)
1644 del_timer(&block->timer);
1645 else
1646 mod_timer(&block->timer, jiffies + expires);
1647 }
1648
1649 /*
1650 * Clear timeout for a dasd_block.
1651 */
1652 void dasd_block_clear_timer(struct dasd_block *block)
1653 {
1654 del_timer(&block->timer);
1655 }
1656
1657 /*
1658 * Process finished error recovery ccw.
1659 */
1660 static inline void __dasd_block_process_erp(struct dasd_block *block,
1661 struct dasd_ccw_req *cqr)
1662 {
1663 dasd_erp_fn_t erp_fn;
1664 struct dasd_device *device = block->base;
1665
1666 if (cqr->status == DASD_CQR_DONE)
1667 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
1668 else
1669 dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
1670 erp_fn = device->discipline->erp_postaction(cqr);
1671 erp_fn(cqr);
1672 }
1673
1674 /*
1675 * Fetch requests from the block device queue.
1676 */
1677 static void __dasd_process_request_queue(struct dasd_block *block)
1678 {
1679 struct request_queue *queue;
1680 struct request *req;
1681 struct dasd_ccw_req *cqr;
1682 struct dasd_device *basedev;
1683 unsigned long flags;
1684 queue = block->request_queue;
1685 basedev = block->base;
1686 /* No queue ? Then there is nothing to do. */
1687 if (queue == NULL)
1688 return;
1689
1690 /*
1691 * We requeue request from the block device queue to the ccw
1692 * queue only in two states. In state DASD_STATE_READY the
1693 * partition detection is done and we need to requeue requests
1694 * for that. State DASD_STATE_ONLINE is normal block device
1695 * operation.
1696 */
1697 if (basedev->state < DASD_STATE_READY) {
1698 while ((req = blk_fetch_request(block->request_queue)))
1699 __blk_end_request_all(req, -EIO);
1700 return;
1701 }
1702 /* Now we try to fetch requests from the request queue */
1703 while (!blk_queue_plugged(queue) && (req = blk_peek_request(queue))) {
1704 if (basedev->features & DASD_FEATURE_READONLY &&
1705 rq_data_dir(req) == WRITE) {
1706 DBF_DEV_EVENT(DBF_ERR, basedev,
1707 "Rejecting write request %p",
1708 req);
1709 blk_start_request(req);
1710 __blk_end_request_all(req, -EIO);
1711 continue;
1712 }
1713 cqr = basedev->discipline->build_cp(basedev, block, req);
1714 if (IS_ERR(cqr)) {
1715 if (PTR_ERR(cqr) == -EBUSY)
1716 break; /* normal end condition */
1717 if (PTR_ERR(cqr) == -ENOMEM)
1718 break; /* terminate request queue loop */
1719 if (PTR_ERR(cqr) == -EAGAIN) {
1720 /*
1721 * The current request cannot be build right
1722 * now, we have to try later. If this request
1723 * is the head-of-queue we stop the device
1724 * for 1/2 second.
1725 */
1726 if (!list_empty(&block->ccw_queue))
1727 break;
1728 spin_lock_irqsave(get_ccwdev_lock(basedev->cdev), flags);
1729 basedev->stopped |= DASD_STOPPED_PENDING;
1730 spin_unlock_irqrestore(get_ccwdev_lock(basedev->cdev), flags);
1731 dasd_block_set_timer(block, HZ/2);
1732 break;
1733 }
1734 DBF_DEV_EVENT(DBF_ERR, basedev,
1735 "CCW creation failed (rc=%ld) "
1736 "on request %p",
1737 PTR_ERR(cqr), req);
1738 blk_start_request(req);
1739 __blk_end_request_all(req, -EIO);
1740 continue;
1741 }
1742 /*
1743 * Note: callback is set to dasd_return_cqr_cb in
1744 * __dasd_block_start_head to cover erp requests as well
1745 */
1746 cqr->callback_data = (void *) req;
1747 cqr->status = DASD_CQR_FILLED;
1748 blk_start_request(req);
1749 list_add_tail(&cqr->blocklist, &block->ccw_queue);
1750 dasd_profile_start(block, cqr, req);
1751 }
1752 }
1753
1754 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
1755 {
1756 struct request *req;
1757 int status;
1758 int error = 0;
1759
1760 req = (struct request *) cqr->callback_data;
1761 dasd_profile_end(cqr->block, cqr, req);
1762 status = cqr->block->base->discipline->free_cp(cqr, req);
1763 if (status <= 0)
1764 error = status ? status : -EIO;
1765 __blk_end_request_all(req, error);
1766 }
1767
1768 /*
1769 * Process ccw request queue.
1770 */
1771 static void __dasd_process_block_ccw_queue(struct dasd_block *block,
1772 struct list_head *final_queue)
1773 {
1774 struct list_head *l, *n;
1775 struct dasd_ccw_req *cqr;
1776 dasd_erp_fn_t erp_fn;
1777 unsigned long flags;
1778 struct dasd_device *base = block->base;
1779
1780 restart:
1781 /* Process request with final status. */
1782 list_for_each_safe(l, n, &block->ccw_queue) {
1783 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
1784 if (cqr->status != DASD_CQR_DONE &&
1785 cqr->status != DASD_CQR_FAILED &&
1786 cqr->status != DASD_CQR_NEED_ERP &&
1787 cqr->status != DASD_CQR_TERMINATED)
1788 continue;
1789
1790 if (cqr->status == DASD_CQR_TERMINATED) {
1791 base->discipline->handle_terminated_request(cqr);
1792 goto restart;
1793 }
1794
1795 /* Process requests that may be recovered */
1796 if (cqr->status == DASD_CQR_NEED_ERP) {
1797 erp_fn = base->discipline->erp_action(cqr);
1798 erp_fn(cqr);
1799 goto restart;
1800 }
1801
1802 /* log sense for fatal error */
1803 if (cqr->status == DASD_CQR_FAILED) {
1804 dasd_log_sense(cqr, &cqr->irb);
1805 }
1806
1807 /* First of all call extended error reporting. */
1808 if (dasd_eer_enabled(base) &&
1809 cqr->status == DASD_CQR_FAILED) {
1810 dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
1811
1812 /* restart request */
1813 cqr->status = DASD_CQR_FILLED;
1814 cqr->retries = 255;
1815 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
1816 base->stopped |= DASD_STOPPED_QUIESCE;
1817 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
1818 flags);
1819 goto restart;
1820 }
1821
1822 /* Process finished ERP request. */
1823 if (cqr->refers) {
1824 __dasd_block_process_erp(block, cqr);
1825 goto restart;
1826 }
1827
1828 /* Rechain finished requests to final queue */
1829 cqr->endclk = get_clock();
1830 list_move_tail(&cqr->blocklist, final_queue);
1831 }
1832 }
1833
1834 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
1835 {
1836 dasd_schedule_block_bh(cqr->block);
1837 }
1838
1839 static void __dasd_block_start_head(struct dasd_block *block)
1840 {
1841 struct dasd_ccw_req *cqr;
1842
1843 if (list_empty(&block->ccw_queue))
1844 return;
1845 /* We allways begin with the first requests on the queue, as some
1846 * of previously started requests have to be enqueued on a
1847 * dasd_device again for error recovery.
1848 */
1849 list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
1850 if (cqr->status != DASD_CQR_FILLED)
1851 continue;
1852 /* Non-temporary stop condition will trigger fail fast */
1853 if (block->base->stopped & ~DASD_STOPPED_PENDING &&
1854 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
1855 (!dasd_eer_enabled(block->base))) {
1856 cqr->status = DASD_CQR_FAILED;
1857 dasd_schedule_block_bh(block);
1858 continue;
1859 }
1860 /* Don't try to start requests if device is stopped */
1861 if (block->base->stopped)
1862 return;
1863
1864 /* just a fail safe check, should not happen */
1865 if (!cqr->startdev)
1866 cqr->startdev = block->base;
1867
1868 /* make sure that the requests we submit find their way back */
1869 cqr->callback = dasd_return_cqr_cb;
1870
1871 dasd_add_request_tail(cqr);
1872 }
1873 }
1874
1875 /*
1876 * Central dasd_block layer routine. Takes requests from the generic
1877 * block layer request queue, creates ccw requests, enqueues them on
1878 * a dasd_device and processes ccw requests that have been returned.
1879 */
1880 static void dasd_block_tasklet(struct dasd_block *block)
1881 {
1882 struct list_head final_queue;
1883 struct list_head *l, *n;
1884 struct dasd_ccw_req *cqr;
1885
1886 atomic_set(&block->tasklet_scheduled, 0);
1887 INIT_LIST_HEAD(&final_queue);
1888 spin_lock(&block->queue_lock);
1889 /* Finish off requests on ccw queue */
1890 __dasd_process_block_ccw_queue(block, &final_queue);
1891 spin_unlock(&block->queue_lock);
1892 /* Now call the callback function of requests with final status */
1893 spin_lock_irq(&block->request_queue_lock);
1894 list_for_each_safe(l, n, &final_queue) {
1895 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
1896 list_del_init(&cqr->blocklist);
1897 __dasd_cleanup_cqr(cqr);
1898 }
1899 spin_lock(&block->queue_lock);
1900 /* Get new request from the block device request queue */
1901 __dasd_process_request_queue(block);
1902 /* Now check if the head of the ccw queue needs to be started. */
1903 __dasd_block_start_head(block);
1904 spin_unlock(&block->queue_lock);
1905 spin_unlock_irq(&block->request_queue_lock);
1906 dasd_put_device(block->base);
1907 }
1908
1909 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
1910 {
1911 wake_up(&dasd_flush_wq);
1912 }
1913
1914 /*
1915 * Go through all request on the dasd_block request queue, cancel them
1916 * on the respective dasd_device, and return them to the generic
1917 * block layer.
1918 */
1919 static int dasd_flush_block_queue(struct dasd_block *block)
1920 {
1921 struct dasd_ccw_req *cqr, *n;
1922 int rc, i;
1923 struct list_head flush_queue;
1924
1925 INIT_LIST_HEAD(&flush_queue);
1926 spin_lock_bh(&block->queue_lock);
1927 rc = 0;
1928 restart:
1929 list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
1930 /* if this request currently owned by a dasd_device cancel it */
1931 if (cqr->status >= DASD_CQR_QUEUED)
1932 rc = dasd_cancel_req(cqr);
1933 if (rc < 0)
1934 break;
1935 /* Rechain request (including erp chain) so it won't be
1936 * touched by the dasd_block_tasklet anymore.
1937 * Replace the callback so we notice when the request
1938 * is returned from the dasd_device layer.
1939 */
1940 cqr->callback = _dasd_wake_block_flush_cb;
1941 for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
1942 list_move_tail(&cqr->blocklist, &flush_queue);
1943 if (i > 1)
1944 /* moved more than one request - need to restart */
1945 goto restart;
1946 }
1947 spin_unlock_bh(&block->queue_lock);
1948 /* Now call the callback function of flushed requests */
1949 restart_cb:
1950 list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
1951 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
1952 /* Process finished ERP request. */
1953 if (cqr->refers) {
1954 spin_lock_bh(&block->queue_lock);
1955 __dasd_block_process_erp(block, cqr);
1956 spin_unlock_bh(&block->queue_lock);
1957 /* restart list_for_xx loop since dasd_process_erp
1958 * might remove multiple elements */
1959 goto restart_cb;
1960 }
1961 /* call the callback function */
1962 spin_lock_irq(&block->request_queue_lock);
1963 cqr->endclk = get_clock();
1964 list_del_init(&cqr->blocklist);
1965 __dasd_cleanup_cqr(cqr);
1966 spin_unlock_irq(&block->request_queue_lock);
1967 }
1968 return rc;
1969 }
1970
1971 /*
1972 * Schedules a call to dasd_tasklet over the device tasklet.
1973 */
1974 void dasd_schedule_block_bh(struct dasd_block *block)
1975 {
1976 /* Protect against rescheduling. */
1977 if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
1978 return;
1979 /* life cycle of block is bound to it's base device */
1980 dasd_get_device(block->base);
1981 tasklet_hi_schedule(&block->tasklet);
1982 }
1983
1984
1985 /*
1986 * SECTION: external block device operations
1987 * (request queue handling, open, release, etc.)
1988 */
1989
1990 /*
1991 * Dasd request queue function. Called from ll_rw_blk.c
1992 */
1993 static void do_dasd_request(struct request_queue *queue)
1994 {
1995 struct dasd_block *block;
1996
1997 block = queue->queuedata;
1998 spin_lock(&block->queue_lock);
1999 /* Get new request from the block device request queue */
2000 __dasd_process_request_queue(block);
2001 /* Now check if the head of the ccw queue needs to be started. */
2002 __dasd_block_start_head(block);
2003 spin_unlock(&block->queue_lock);
2004 }
2005
2006 /*
2007 * Allocate and initialize request queue and default I/O scheduler.
2008 */
2009 static int dasd_alloc_queue(struct dasd_block *block)
2010 {
2011 int rc;
2012
2013 block->request_queue = blk_init_queue(do_dasd_request,
2014 &block->request_queue_lock);
2015 if (block->request_queue == NULL)
2016 return -ENOMEM;
2017
2018 block->request_queue->queuedata = block;
2019
2020 elevator_exit(block->request_queue->elevator);
2021 block->request_queue->elevator = NULL;
2022 rc = elevator_init(block->request_queue, "deadline");
2023 if (rc) {
2024 blk_cleanup_queue(block->request_queue);
2025 return rc;
2026 }
2027 return 0;
2028 }
2029
2030 /*
2031 * Allocate and initialize request queue.
2032 */
2033 static void dasd_setup_queue(struct dasd_block *block)
2034 {
2035 int max;
2036
2037 blk_queue_logical_block_size(block->request_queue, block->bp_block);
2038 max = block->base->discipline->max_blocks << block->s2b_shift;
2039 blk_queue_max_sectors(block->request_queue, max);
2040 blk_queue_max_phys_segments(block->request_queue, -1L);
2041 blk_queue_max_hw_segments(block->request_queue, -1L);
2042 /* with page sized segments we can translate each segement into
2043 * one idaw/tidaw
2044 */
2045 blk_queue_max_segment_size(block->request_queue, PAGE_SIZE);
2046 blk_queue_segment_boundary(block->request_queue, PAGE_SIZE - 1);
2047 blk_queue_ordered(block->request_queue, QUEUE_ORDERED_DRAIN, NULL);
2048 }
2049
2050 /*
2051 * Deactivate and free request queue.
2052 */
2053 static void dasd_free_queue(struct dasd_block *block)
2054 {
2055 if (block->request_queue) {
2056 blk_cleanup_queue(block->request_queue);
2057 block->request_queue = NULL;
2058 }
2059 }
2060
2061 /*
2062 * Flush request on the request queue.
2063 */
2064 static void dasd_flush_request_queue(struct dasd_block *block)
2065 {
2066 struct request *req;
2067
2068 if (!block->request_queue)
2069 return;
2070
2071 spin_lock_irq(&block->request_queue_lock);
2072 while ((req = blk_fetch_request(block->request_queue)))
2073 __blk_end_request_all(req, -EIO);
2074 spin_unlock_irq(&block->request_queue_lock);
2075 }
2076
2077 static int dasd_open(struct block_device *bdev, fmode_t mode)
2078 {
2079 struct dasd_block *block = bdev->bd_disk->private_data;
2080 struct dasd_device *base = block->base;
2081 int rc;
2082
2083 atomic_inc(&block->open_count);
2084 if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
2085 rc = -ENODEV;
2086 goto unlock;
2087 }
2088
2089 if (!try_module_get(base->discipline->owner)) {
2090 rc = -EINVAL;
2091 goto unlock;
2092 }
2093
2094 if (dasd_probeonly) {
2095 dev_info(&base->cdev->dev,
2096 "Accessing the DASD failed because it is in "
2097 "probeonly mode\n");
2098 rc = -EPERM;
2099 goto out;
2100 }
2101
2102 if (base->state <= DASD_STATE_BASIC) {
2103 DBF_DEV_EVENT(DBF_ERR, base, " %s",
2104 " Cannot open unrecognized device");
2105 rc = -ENODEV;
2106 goto out;
2107 }
2108
2109 return 0;
2110
2111 out:
2112 module_put(base->discipline->owner);
2113 unlock:
2114 atomic_dec(&block->open_count);
2115 return rc;
2116 }
2117
2118 static int dasd_release(struct gendisk *disk, fmode_t mode)
2119 {
2120 struct dasd_block *block = disk->private_data;
2121
2122 atomic_dec(&block->open_count);
2123 module_put(block->base->discipline->owner);
2124 return 0;
2125 }
2126
2127 /*
2128 * Return disk geometry.
2129 */
2130 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
2131 {
2132 struct dasd_block *block;
2133 struct dasd_device *base;
2134
2135 block = bdev->bd_disk->private_data;
2136 if (!block)
2137 return -ENODEV;
2138 base = block->base;
2139
2140 if (!base->discipline ||
2141 !base->discipline->fill_geometry)
2142 return -EINVAL;
2143
2144 base->discipline->fill_geometry(block, geo);
2145 geo->start = get_start_sect(bdev) >> block->s2b_shift;
2146 return 0;
2147 }
2148
2149 const struct block_device_operations
2150 dasd_device_operations = {
2151 .owner = THIS_MODULE,
2152 .open = dasd_open,
2153 .release = dasd_release,
2154 .ioctl = dasd_ioctl,
2155 .compat_ioctl = dasd_ioctl,
2156 .getgeo = dasd_getgeo,
2157 };
2158
2159 /*******************************************************************************
2160 * end of block device operations
2161 */
2162
2163 static void
2164 dasd_exit(void)
2165 {
2166 #ifdef CONFIG_PROC_FS
2167 dasd_proc_exit();
2168 #endif
2169 dasd_eer_exit();
2170 if (dasd_page_cache != NULL) {
2171 kmem_cache_destroy(dasd_page_cache);
2172 dasd_page_cache = NULL;
2173 }
2174 dasd_gendisk_exit();
2175 dasd_devmap_exit();
2176 if (dasd_debug_area != NULL) {
2177 debug_unregister(dasd_debug_area);
2178 dasd_debug_area = NULL;
2179 }
2180 }
2181
2182 /*
2183 * SECTION: common functions for ccw_driver use
2184 */
2185
2186 static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
2187 {
2188 struct ccw_device *cdev = data;
2189 int ret;
2190
2191 ret = ccw_device_set_online(cdev);
2192 if (ret)
2193 pr_warning("%s: Setting the DASD online failed with rc=%d\n",
2194 dev_name(&cdev->dev), ret);
2195 else {
2196 struct dasd_device *device = dasd_device_from_cdev(cdev);
2197 wait_event(dasd_init_waitq, _wait_for_device(device));
2198 dasd_put_device(device);
2199 }
2200 }
2201
2202 /*
2203 * Initial attempt at a probe function. this can be simplified once
2204 * the other detection code is gone.
2205 */
2206 int dasd_generic_probe(struct ccw_device *cdev,
2207 struct dasd_discipline *discipline)
2208 {
2209 int ret;
2210
2211 ret = ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP);
2212 if (ret) {
2213 DBF_EVENT(DBF_WARNING,
2214 "dasd_generic_probe: could not set ccw-device options "
2215 "for %s\n", dev_name(&cdev->dev));
2216 return ret;
2217 }
2218 ret = dasd_add_sysfs_files(cdev);
2219 if (ret) {
2220 DBF_EVENT(DBF_WARNING,
2221 "dasd_generic_probe: could not add sysfs entries "
2222 "for %s\n", dev_name(&cdev->dev));
2223 return ret;
2224 }
2225 cdev->handler = &dasd_int_handler;
2226
2227 /*
2228 * Automatically online either all dasd devices (dasd_autodetect)
2229 * or all devices specified with dasd= parameters during
2230 * initial probe.
2231 */
2232 if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
2233 (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
2234 async_schedule(dasd_generic_auto_online, cdev);
2235 return 0;
2236 }
2237
2238 /*
2239 * This will one day be called from a global not_oper handler.
2240 * It is also used by driver_unregister during module unload.
2241 */
2242 void dasd_generic_remove(struct ccw_device *cdev)
2243 {
2244 struct dasd_device *device;
2245 struct dasd_block *block;
2246
2247 cdev->handler = NULL;
2248
2249 dasd_remove_sysfs_files(cdev);
2250 device = dasd_device_from_cdev(cdev);
2251 if (IS_ERR(device))
2252 return;
2253 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
2254 /* Already doing offline processing */
2255 dasd_put_device(device);
2256 return;
2257 }
2258 /*
2259 * This device is removed unconditionally. Set offline
2260 * flag to prevent dasd_open from opening it while it is
2261 * no quite down yet.
2262 */
2263 dasd_set_target_state(device, DASD_STATE_NEW);
2264 /* dasd_delete_device destroys the device reference. */
2265 block = device->block;
2266 device->block = NULL;
2267 dasd_delete_device(device);
2268 /*
2269 * life cycle of block is bound to device, so delete it after
2270 * device was safely removed
2271 */
2272 if (block)
2273 dasd_free_block(block);
2274 }
2275
2276 /*
2277 * Activate a device. This is called from dasd_{eckd,fba}_probe() when either
2278 * the device is detected for the first time and is supposed to be used
2279 * or the user has started activation through sysfs.
2280 */
2281 int dasd_generic_set_online(struct ccw_device *cdev,
2282 struct dasd_discipline *base_discipline)
2283 {
2284 struct dasd_discipline *discipline;
2285 struct dasd_device *device;
2286 int rc;
2287
2288 /* first online clears initial online feature flag */
2289 dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
2290 device = dasd_create_device(cdev);
2291 if (IS_ERR(device))
2292 return PTR_ERR(device);
2293
2294 discipline = base_discipline;
2295 if (device->features & DASD_FEATURE_USEDIAG) {
2296 if (!dasd_diag_discipline_pointer) {
2297 pr_warning("%s Setting the DASD online failed because "
2298 "of missing DIAG discipline\n",
2299 dev_name(&cdev->dev));
2300 dasd_delete_device(device);
2301 return -ENODEV;
2302 }
2303 discipline = dasd_diag_discipline_pointer;
2304 }
2305 if (!try_module_get(base_discipline->owner)) {
2306 dasd_delete_device(device);
2307 return -EINVAL;
2308 }
2309 if (!try_module_get(discipline->owner)) {
2310 module_put(base_discipline->owner);
2311 dasd_delete_device(device);
2312 return -EINVAL;
2313 }
2314 device->base_discipline = base_discipline;
2315 device->discipline = discipline;
2316
2317 /* check_device will allocate block device if necessary */
2318 rc = discipline->check_device(device);
2319 if (rc) {
2320 pr_warning("%s Setting the DASD online with discipline %s "
2321 "failed with rc=%i\n",
2322 dev_name(&cdev->dev), discipline->name, rc);
2323 module_put(discipline->owner);
2324 module_put(base_discipline->owner);
2325 dasd_delete_device(device);
2326 return rc;
2327 }
2328
2329 dasd_set_target_state(device, DASD_STATE_ONLINE);
2330 if (device->state <= DASD_STATE_KNOWN) {
2331 pr_warning("%s Setting the DASD online failed because of a "
2332 "missing discipline\n", dev_name(&cdev->dev));
2333 rc = -ENODEV;
2334 dasd_set_target_state(device, DASD_STATE_NEW);
2335 if (device->block)
2336 dasd_free_block(device->block);
2337 dasd_delete_device(device);
2338 } else
2339 pr_debug("dasd_generic device %s found\n",
2340 dev_name(&cdev->dev));
2341 dasd_put_device(device);
2342 return rc;
2343 }
2344
2345 int dasd_generic_set_offline(struct ccw_device *cdev)
2346 {
2347 struct dasd_device *device;
2348 struct dasd_block *block;
2349 int max_count, open_count;
2350
2351 device = dasd_device_from_cdev(cdev);
2352 if (IS_ERR(device))
2353 return PTR_ERR(device);
2354 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
2355 /* Already doing offline processing */
2356 dasd_put_device(device);
2357 return 0;
2358 }
2359 /*
2360 * We must make sure that this device is currently not in use.
2361 * The open_count is increased for every opener, that includes
2362 * the blkdev_get in dasd_scan_partitions. We are only interested
2363 * in the other openers.
2364 */
2365 if (device->block) {
2366 max_count = device->block->bdev ? 0 : -1;
2367 open_count = atomic_read(&device->block->open_count);
2368 if (open_count > max_count) {
2369 if (open_count > 0)
2370 pr_warning("%s: The DASD cannot be set offline "
2371 "with open count %i\n",
2372 dev_name(&cdev->dev), open_count);
2373 else
2374 pr_warning("%s: The DASD cannot be set offline "
2375 "while it is in use\n",
2376 dev_name(&cdev->dev));
2377 clear_bit(DASD_FLAG_OFFLINE, &device->flags);
2378 dasd_put_device(device);
2379 return -EBUSY;
2380 }
2381 }
2382 dasd_set_target_state(device, DASD_STATE_NEW);
2383 /* dasd_delete_device destroys the device reference. */
2384 block = device->block;
2385 device->block = NULL;
2386 dasd_delete_device(device);
2387 /*
2388 * life cycle of block is bound to device, so delete it after
2389 * device was safely removed
2390 */
2391 if (block)
2392 dasd_free_block(block);
2393 return 0;
2394 }
2395
2396 int dasd_generic_notify(struct ccw_device *cdev, int event)
2397 {
2398 struct dasd_device *device;
2399 struct dasd_ccw_req *cqr;
2400 int ret;
2401
2402 device = dasd_device_from_cdev_locked(cdev);
2403 if (IS_ERR(device))
2404 return 0;
2405 ret = 0;
2406 switch (event) {
2407 case CIO_GONE:
2408 case CIO_BOXED:
2409 case CIO_NO_PATH:
2410 /* First of all call extended error reporting. */
2411 dasd_eer_write(device, NULL, DASD_EER_NOPATH);
2412
2413 if (device->state < DASD_STATE_BASIC)
2414 break;
2415 /* Device is active. We want to keep it. */
2416 list_for_each_entry(cqr, &device->ccw_queue, devlist)
2417 if (cqr->status == DASD_CQR_IN_IO) {
2418 cqr->status = DASD_CQR_QUEUED;
2419 cqr->retries++;
2420 }
2421 device->stopped |= DASD_STOPPED_DC_WAIT;
2422 dasd_device_clear_timer(device);
2423 dasd_schedule_device_bh(device);
2424 ret = 1;
2425 break;
2426 case CIO_OPER:
2427 /* FIXME: add a sanity check. */
2428 device->stopped &= ~DASD_STOPPED_DC_WAIT;
2429 if (device->stopped & DASD_UNRESUMED_PM) {
2430 device->stopped &= ~DASD_UNRESUMED_PM;
2431 dasd_restore_device(device);
2432 ret = 1;
2433 break;
2434 }
2435 dasd_schedule_device_bh(device);
2436 if (device->block)
2437 dasd_schedule_block_bh(device->block);
2438 ret = 1;
2439 break;
2440 }
2441 dasd_put_device(device);
2442 return ret;
2443 }
2444
2445 int dasd_generic_pm_freeze(struct ccw_device *cdev)
2446 {
2447 struct dasd_ccw_req *cqr, *n;
2448 int rc;
2449 struct list_head freeze_queue;
2450 struct dasd_device *device = dasd_device_from_cdev(cdev);
2451
2452 if (IS_ERR(device))
2453 return PTR_ERR(device);
2454 /* disallow new I/O */
2455 device->stopped |= DASD_STOPPED_PM;
2456 /* clear active requests */
2457 INIT_LIST_HEAD(&freeze_queue);
2458 spin_lock_irq(get_ccwdev_lock(cdev));
2459 rc = 0;
2460 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
2461 /* Check status and move request to flush_queue */
2462 if (cqr->status == DASD_CQR_IN_IO) {
2463 rc = device->discipline->term_IO(cqr);
2464 if (rc) {
2465 /* unable to terminate requeust */
2466 dev_err(&device->cdev->dev,
2467 "Unable to terminate request %p "
2468 "on suspend\n", cqr);
2469 spin_unlock_irq(get_ccwdev_lock(cdev));
2470 dasd_put_device(device);
2471 return rc;
2472 }
2473 }
2474 list_move_tail(&cqr->devlist, &freeze_queue);
2475 }
2476
2477 spin_unlock_irq(get_ccwdev_lock(cdev));
2478
2479 list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) {
2480 wait_event(dasd_flush_wq,
2481 (cqr->status != DASD_CQR_CLEAR_PENDING));
2482 if (cqr->status == DASD_CQR_CLEARED)
2483 cqr->status = DASD_CQR_QUEUED;
2484 }
2485 /* move freeze_queue to start of the ccw_queue */
2486 spin_lock_irq(get_ccwdev_lock(cdev));
2487 list_splice_tail(&freeze_queue, &device->ccw_queue);
2488 spin_unlock_irq(get_ccwdev_lock(cdev));
2489
2490 if (device->discipline->freeze)
2491 rc = device->discipline->freeze(device);
2492
2493 dasd_put_device(device);
2494 return rc;
2495 }
2496 EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze);
2497
2498 int dasd_generic_restore_device(struct ccw_device *cdev)
2499 {
2500 struct dasd_device *device = dasd_device_from_cdev(cdev);
2501 int rc = 0;
2502
2503 if (IS_ERR(device))
2504 return PTR_ERR(device);
2505
2506 /* allow new IO again */
2507 device->stopped &= ~DASD_STOPPED_PM;
2508 device->stopped &= ~DASD_UNRESUMED_PM;
2509
2510 dasd_schedule_device_bh(device);
2511 if (device->block)
2512 dasd_schedule_block_bh(device->block);
2513
2514 if (device->discipline->restore)
2515 rc = device->discipline->restore(device);
2516 if (rc)
2517 /*
2518 * if the resume failed for the DASD we put it in
2519 * an UNRESUMED stop state
2520 */
2521 device->stopped |= DASD_UNRESUMED_PM;
2522
2523 dasd_put_device(device);
2524 return 0;
2525 }
2526 EXPORT_SYMBOL_GPL(dasd_generic_restore_device);
2527
2528 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
2529 void *rdc_buffer,
2530 int rdc_buffer_size,
2531 int magic)
2532 {
2533 struct dasd_ccw_req *cqr;
2534 struct ccw1 *ccw;
2535
2536 cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device);
2537
2538 if (IS_ERR(cqr)) {
2539 /* internal error 13 - Allocating the RDC request failed*/
2540 dev_err(&device->cdev->dev,
2541 "An error occurred in the DASD device driver, "
2542 "reason=%s\n", "13");
2543 return cqr;
2544 }
2545
2546 ccw = cqr->cpaddr;
2547 ccw->cmd_code = CCW_CMD_RDC;
2548 ccw->cda = (__u32)(addr_t)rdc_buffer;
2549 ccw->count = rdc_buffer_size;
2550
2551 cqr->startdev = device;
2552 cqr->memdev = device;
2553 cqr->expires = 10*HZ;
2554 clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
2555 cqr->retries = 2;
2556 cqr->buildclk = get_clock();
2557 cqr->status = DASD_CQR_FILLED;
2558 return cqr;
2559 }
2560
2561
2562 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
2563 void *rdc_buffer, int rdc_buffer_size)
2564 {
2565 int ret;
2566 struct dasd_ccw_req *cqr;
2567
2568 cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size,
2569 magic);
2570 if (IS_ERR(cqr))
2571 return PTR_ERR(cqr);
2572
2573 ret = dasd_sleep_on(cqr);
2574 dasd_sfree_request(cqr, cqr->memdev);
2575 return ret;
2576 }
2577 EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
2578
2579 /*
2580 * In command mode and transport mode we need to look for sense
2581 * data in different places. The sense data itself is allways
2582 * an array of 32 bytes, so we can unify the sense data access
2583 * for both modes.
2584 */
2585 char *dasd_get_sense(struct irb *irb)
2586 {
2587 struct tsb *tsb = NULL;
2588 char *sense = NULL;
2589
2590 if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
2591 if (irb->scsw.tm.tcw)
2592 tsb = tcw_get_tsb((struct tcw *)(unsigned long)
2593 irb->scsw.tm.tcw);
2594 if (tsb && tsb->length == 64 && tsb->flags)
2595 switch (tsb->flags & 0x07) {
2596 case 1: /* tsa_iostat */
2597 sense = tsb->tsa.iostat.sense;
2598 break;
2599 case 2: /* tsa_ddpc */
2600 sense = tsb->tsa.ddpc.sense;
2601 break;
2602 default:
2603 /* currently we don't use interrogate data */
2604 break;
2605 }
2606 } else if (irb->esw.esw0.erw.cons) {
2607 sense = irb->ecw;
2608 }
2609 return sense;
2610 }
2611 EXPORT_SYMBOL_GPL(dasd_get_sense);
2612
2613 static int __init dasd_init(void)
2614 {
2615 int rc;
2616
2617 init_waitqueue_head(&dasd_init_waitq);
2618 init_waitqueue_head(&dasd_flush_wq);
2619 init_waitqueue_head(&generic_waitq);
2620
2621 /* register 'common' DASD debug area, used for all DBF_XXX calls */
2622 dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
2623 if (dasd_debug_area == NULL) {
2624 rc = -ENOMEM;
2625 goto failed;
2626 }
2627 debug_register_view(dasd_debug_area, &debug_sprintf_view);
2628 debug_set_level(dasd_debug_area, DBF_WARNING);
2629
2630 DBF_EVENT(DBF_EMERG, "%s", "debug area created");
2631
2632 dasd_diag_discipline_pointer = NULL;
2633
2634 rc = dasd_devmap_init();
2635 if (rc)
2636 goto failed;
2637 rc = dasd_gendisk_init();
2638 if (rc)
2639 goto failed;
2640 rc = dasd_parse();
2641 if (rc)
2642 goto failed;
2643 rc = dasd_eer_init();
2644 if (rc)
2645 goto failed;
2646 #ifdef CONFIG_PROC_FS
2647 rc = dasd_proc_init();
2648 if (rc)
2649 goto failed;
2650 #endif
2651
2652 return 0;
2653 failed:
2654 pr_info("The DASD device driver could not be initialized\n");
2655 dasd_exit();
2656 return rc;
2657 }
2658
2659 module_init(dasd_init);
2660 module_exit(dasd_exit);
2661
2662 EXPORT_SYMBOL(dasd_debug_area);
2663 EXPORT_SYMBOL(dasd_diag_discipline_pointer);
2664
2665 EXPORT_SYMBOL(dasd_add_request_head);
2666 EXPORT_SYMBOL(dasd_add_request_tail);
2667 EXPORT_SYMBOL(dasd_cancel_req);
2668 EXPORT_SYMBOL(dasd_device_clear_timer);
2669 EXPORT_SYMBOL(dasd_block_clear_timer);
2670 EXPORT_SYMBOL(dasd_enable_device);
2671 EXPORT_SYMBOL(dasd_int_handler);
2672 EXPORT_SYMBOL(dasd_kfree_request);
2673 EXPORT_SYMBOL(dasd_kick_device);
2674 EXPORT_SYMBOL(dasd_kmalloc_request);
2675 EXPORT_SYMBOL(dasd_schedule_device_bh);
2676 EXPORT_SYMBOL(dasd_schedule_block_bh);
2677 EXPORT_SYMBOL(dasd_set_target_state);
2678 EXPORT_SYMBOL(dasd_device_set_timer);
2679 EXPORT_SYMBOL(dasd_block_set_timer);
2680 EXPORT_SYMBOL(dasd_sfree_request);
2681 EXPORT_SYMBOL(dasd_sleep_on);
2682 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
2683 EXPORT_SYMBOL(dasd_sleep_on_interruptible);
2684 EXPORT_SYMBOL(dasd_smalloc_request);
2685 EXPORT_SYMBOL(dasd_start_IO);
2686 EXPORT_SYMBOL(dasd_term_IO);
2687
2688 EXPORT_SYMBOL_GPL(dasd_generic_probe);
2689 EXPORT_SYMBOL_GPL(dasd_generic_remove);
2690 EXPORT_SYMBOL_GPL(dasd_generic_notify);
2691 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
2692 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
2693 EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
2694 EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
2695 EXPORT_SYMBOL_GPL(dasd_alloc_block);
2696 EXPORT_SYMBOL_GPL(dasd_free_block);