Merge branches 'fixes' and 'mmci' into for-linus
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / s390 / block / dasd_diag.c
1 /*
2 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
3 * Based on.......: linux/drivers/s390/block/mdisk.c
4 * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
5 * Bugreports.to..: <Linux390@de.ibm.com>
6 * Copyright IBM Corp. 1999, 2000
7 *
8 */
9
10 #define KMSG_COMPONENT "dasd"
11
12 #include <linux/kernel_stat.h>
13 #include <linux/stddef.h>
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/hdreg.h>
17 #include <linux/bio.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/jiffies.h>
21
22 #include <asm/dasd.h>
23 #include <asm/debug.h>
24 #include <asm/ebcdic.h>
25 #include <asm/io.h>
26 #include <asm/irq.h>
27 #include <asm/vtoc.h>
28 #include <asm/diag.h>
29
30 #include "dasd_int.h"
31 #include "dasd_diag.h"
32
33 #define PRINTK_HEADER "dasd(diag):"
34
35 MODULE_LICENSE("GPL");
36
37 /* The maximum number of blocks per request (max_blocks) is dependent on the
38 * amount of storage that is available in the static I/O buffer for each
39 * device. Currently each device gets 2 pages. We want to fit two requests
40 * into the available memory so that we can immediately start the next if one
41 * finishes. */
42 #define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \
43 sizeof(struct dasd_diag_req)) / \
44 sizeof(struct dasd_diag_bio)) / 2)
45 #define DIAG_MAX_RETRIES 32
46 #define DIAG_TIMEOUT 50
47
48 static struct dasd_discipline dasd_diag_discipline;
49
50 struct dasd_diag_private {
51 struct dasd_diag_characteristics rdc_data;
52 struct dasd_diag_rw_io iob;
53 struct dasd_diag_init_io iib;
54 blocknum_t pt_block;
55 struct ccw_dev_id dev_id;
56 };
57
58 struct dasd_diag_req {
59 unsigned int block_count;
60 struct dasd_diag_bio bio[0];
61 };
62
63 static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */
64
65 /* Perform DIAG250 call with block I/O parameter list iob (input and output)
66 * and function code cmd.
67 * In case of an exception return 3. Otherwise return result of bitwise OR of
68 * resulting condition code and DIAG return code. */
69 static inline int dia250(void *iob, int cmd)
70 {
71 register unsigned long reg2 asm ("2") = (unsigned long) iob;
72 typedef union {
73 struct dasd_diag_init_io init_io;
74 struct dasd_diag_rw_io rw_io;
75 } addr_type;
76 int rc;
77
78 rc = 3;
79 asm volatile(
80 " diag 2,%2,0x250\n"
81 "0: ipm %0\n"
82 " srl %0,28\n"
83 " or %0,3\n"
84 "1:\n"
85 EX_TABLE(0b,1b)
86 : "+d" (rc), "=m" (*(addr_type *) iob)
87 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob)
88 : "3", "cc");
89 return rc;
90 }
91
92 /* Initialize block I/O to DIAG device using the specified blocksize and
93 * block offset. On success, return zero and set end_block to contain the
94 * number of blocks on the device minus the specified offset. Return non-zero
95 * otherwise. */
96 static inline int
97 mdsk_init_io(struct dasd_device *device, unsigned int blocksize,
98 blocknum_t offset, blocknum_t *end_block)
99 {
100 struct dasd_diag_private *private;
101 struct dasd_diag_init_io *iib;
102 int rc;
103
104 private = (struct dasd_diag_private *) device->private;
105 iib = &private->iib;
106 memset(iib, 0, sizeof (struct dasd_diag_init_io));
107
108 iib->dev_nr = private->dev_id.devno;
109 iib->block_size = blocksize;
110 iib->offset = offset;
111 iib->flaga = DASD_DIAG_FLAGA_DEFAULT;
112
113 rc = dia250(iib, INIT_BIO);
114
115 if ((rc & 3) == 0 && end_block)
116 *end_block = iib->end_block;
117
118 return rc;
119 }
120
121 /* Remove block I/O environment for device. Return zero on success, non-zero
122 * otherwise. */
123 static inline int
124 mdsk_term_io(struct dasd_device * device)
125 {
126 struct dasd_diag_private *private;
127 struct dasd_diag_init_io *iib;
128 int rc;
129
130 private = (struct dasd_diag_private *) device->private;
131 iib = &private->iib;
132 memset(iib, 0, sizeof (struct dasd_diag_init_io));
133 iib->dev_nr = private->dev_id.devno;
134 rc = dia250(iib, TERM_BIO);
135 return rc;
136 }
137
138 /* Error recovery for failed DIAG requests - try to reestablish the DIAG
139 * environment. */
140 static void
141 dasd_diag_erp(struct dasd_device *device)
142 {
143 int rc;
144
145 mdsk_term_io(device);
146 rc = mdsk_init_io(device, device->block->bp_block, 0, NULL);
147 if (rc == 4) {
148 if (!(test_and_set_bit(DASD_FLAG_DEVICE_RO, &device->flags)))
149 pr_warning("%s: The access mode of a DIAG device "
150 "changed to read-only\n",
151 dev_name(&device->cdev->dev));
152 rc = 0;
153 }
154 if (rc)
155 pr_warning("%s: DIAG ERP failed with "
156 "rc=%d\n", dev_name(&device->cdev->dev), rc);
157 }
158
159 /* Start a given request at the device. Return zero on success, non-zero
160 * otherwise. */
161 static int
162 dasd_start_diag(struct dasd_ccw_req * cqr)
163 {
164 struct dasd_device *device;
165 struct dasd_diag_private *private;
166 struct dasd_diag_req *dreq;
167 int rc;
168
169 device = cqr->startdev;
170 if (cqr->retries < 0) {
171 DBF_DEV_EVENT(DBF_ERR, device, "DIAG start_IO: request %p "
172 "- no retry left)", cqr);
173 cqr->status = DASD_CQR_ERROR;
174 return -EIO;
175 }
176 private = (struct dasd_diag_private *) device->private;
177 dreq = (struct dasd_diag_req *) cqr->data;
178
179 private->iob.dev_nr = private->dev_id.devno;
180 private->iob.key = 0;
181 private->iob.flags = DASD_DIAG_RWFLAG_ASYNC;
182 private->iob.block_count = dreq->block_count;
183 private->iob.interrupt_params = (addr_t) cqr;
184 private->iob.bio_list = dreq->bio;
185 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
186
187 cqr->startclk = get_clock();
188 cqr->starttime = jiffies;
189 cqr->retries--;
190
191 rc = dia250(&private->iob, RW_BIO);
192 switch (rc) {
193 case 0: /* Synchronous I/O finished successfully */
194 cqr->stopclk = get_clock();
195 cqr->status = DASD_CQR_SUCCESS;
196 /* Indicate to calling function that only a dasd_schedule_bh()
197 and no timer is needed */
198 rc = -EACCES;
199 break;
200 case 8: /* Asynchronous I/O was started */
201 cqr->status = DASD_CQR_IN_IO;
202 rc = 0;
203 break;
204 default: /* Error condition */
205 cqr->status = DASD_CQR_QUEUED;
206 DBF_DEV_EVENT(DBF_WARNING, device, "dia250 returned rc=%d", rc);
207 dasd_diag_erp(device);
208 rc = -EIO;
209 break;
210 }
211 cqr->intrc = rc;
212 return rc;
213 }
214
215 /* Terminate given request at the device. */
216 static int
217 dasd_diag_term_IO(struct dasd_ccw_req * cqr)
218 {
219 struct dasd_device *device;
220
221 device = cqr->startdev;
222 mdsk_term_io(device);
223 mdsk_init_io(device, device->block->bp_block, 0, NULL);
224 cqr->status = DASD_CQR_CLEAR_PENDING;
225 cqr->stopclk = get_clock();
226 dasd_schedule_device_bh(device);
227 return 0;
228 }
229
230 /* Handle external interruption. */
231 static void dasd_ext_handler(struct ext_code ext_code,
232 unsigned int param32, unsigned long param64)
233 {
234 struct dasd_ccw_req *cqr, *next;
235 struct dasd_device *device;
236 unsigned long long expires;
237 unsigned long flags;
238 addr_t ip;
239 int rc;
240
241 switch (ext_code.subcode >> 8) {
242 case DASD_DIAG_CODE_31BIT:
243 ip = (addr_t) param32;
244 break;
245 case DASD_DIAG_CODE_64BIT:
246 ip = (addr_t) param64;
247 break;
248 default:
249 return;
250 }
251 inc_irq_stat(IRQEXT_DSD);
252 if (!ip) { /* no intparm: unsolicited interrupt */
253 DBF_EVENT(DBF_NOTICE, "%s", "caught unsolicited "
254 "interrupt");
255 return;
256 }
257 cqr = (struct dasd_ccw_req *) ip;
258 device = (struct dasd_device *) cqr->startdev;
259 if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
260 DBF_DEV_EVENT(DBF_WARNING, device,
261 " magic number of dasd_ccw_req 0x%08X doesn't"
262 " match discipline 0x%08X",
263 cqr->magic, *(int *) (&device->discipline->name));
264 return;
265 }
266
267 /* get irq lock to modify request queue */
268 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
269
270 /* Check for a pending clear operation */
271 if (cqr->status == DASD_CQR_CLEAR_PENDING) {
272 cqr->status = DASD_CQR_CLEARED;
273 dasd_device_clear_timer(device);
274 dasd_schedule_device_bh(device);
275 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
276 return;
277 }
278
279 cqr->stopclk = get_clock();
280
281 expires = 0;
282 if ((ext_code.subcode & 0xff) == 0) {
283 cqr->status = DASD_CQR_SUCCESS;
284 /* Start first request on queue if possible -> fast_io. */
285 if (!list_empty(&device->ccw_queue)) {
286 next = list_entry(device->ccw_queue.next,
287 struct dasd_ccw_req, devlist);
288 if (next->status == DASD_CQR_QUEUED) {
289 rc = dasd_start_diag(next);
290 if (rc == 0)
291 expires = next->expires;
292 }
293 }
294 } else {
295 cqr->status = DASD_CQR_QUEUED;
296 DBF_DEV_EVENT(DBF_DEBUG, device, "interrupt status for "
297 "request %p was %d (%d retries left)", cqr,
298 ext_code.subcode & 0xff, cqr->retries);
299 dasd_diag_erp(device);
300 }
301
302 if (expires != 0)
303 dasd_device_set_timer(device, expires);
304 else
305 dasd_device_clear_timer(device);
306 dasd_schedule_device_bh(device);
307
308 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
309 }
310
311 /* Check whether device can be controlled by DIAG discipline. Return zero on
312 * success, non-zero otherwise. */
313 static int
314 dasd_diag_check_device(struct dasd_device *device)
315 {
316 struct dasd_block *block;
317 struct dasd_diag_private *private;
318 struct dasd_diag_characteristics *rdc_data;
319 struct dasd_diag_bio bio;
320 struct vtoc_cms_label *label;
321 blocknum_t end_block;
322 unsigned int sb, bsize;
323 int rc;
324
325 private = (struct dasd_diag_private *) device->private;
326 if (private == NULL) {
327 private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
328 if (private == NULL) {
329 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
330 "Allocating memory for private DASD data "
331 "failed\n");
332 return -ENOMEM;
333 }
334 ccw_device_get_id(device->cdev, &private->dev_id);
335 device->private = (void *) private;
336 }
337 block = dasd_alloc_block();
338 if (IS_ERR(block)) {
339 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
340 "could not allocate dasd block structure");
341 device->private = NULL;
342 kfree(private);
343 return PTR_ERR(block);
344 }
345 device->block = block;
346 block->base = device;
347
348 /* Read Device Characteristics */
349 rdc_data = (void *) &(private->rdc_data);
350 rdc_data->dev_nr = private->dev_id.devno;
351 rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
352
353 rc = diag210((struct diag210 *) rdc_data);
354 if (rc) {
355 DBF_DEV_EVENT(DBF_WARNING, device, "failed to retrieve device "
356 "information (rc=%d)", rc);
357 rc = -EOPNOTSUPP;
358 goto out;
359 }
360
361 device->default_expires = DIAG_TIMEOUT;
362
363 /* Figure out position of label block */
364 switch (private->rdc_data.vdev_class) {
365 case DEV_CLASS_FBA:
366 private->pt_block = 1;
367 break;
368 case DEV_CLASS_ECKD:
369 private->pt_block = 2;
370 break;
371 default:
372 pr_warning("%s: Device type %d is not supported "
373 "in DIAG mode\n", dev_name(&device->cdev->dev),
374 private->rdc_data.vdev_class);
375 rc = -EOPNOTSUPP;
376 goto out;
377 }
378
379 DBF_DEV_EVENT(DBF_INFO, device,
380 "%04X: %04X on real %04X/%02X",
381 rdc_data->dev_nr,
382 rdc_data->vdev_type,
383 rdc_data->rdev_type, rdc_data->rdev_model);
384
385 /* terminate all outstanding operations */
386 mdsk_term_io(device);
387
388 /* figure out blocksize of device */
389 label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL);
390 if (label == NULL) {
391 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
392 "No memory to allocate initialization request");
393 rc = -ENOMEM;
394 goto out;
395 }
396 rc = 0;
397 end_block = 0;
398 /* try all sizes - needed for ECKD devices */
399 for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
400 mdsk_init_io(device, bsize, 0, &end_block);
401 memset(&bio, 0, sizeof (struct dasd_diag_bio));
402 bio.type = MDSK_READ_REQ;
403 bio.block_number = private->pt_block + 1;
404 bio.buffer = label;
405 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
406 private->iob.dev_nr = rdc_data->dev_nr;
407 private->iob.key = 0;
408 private->iob.flags = 0; /* do synchronous io */
409 private->iob.block_count = 1;
410 private->iob.interrupt_params = 0;
411 private->iob.bio_list = &bio;
412 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
413 rc = dia250(&private->iob, RW_BIO);
414 if (rc == 3) {
415 pr_warning("%s: A 64-bit DIAG call failed\n",
416 dev_name(&device->cdev->dev));
417 rc = -EOPNOTSUPP;
418 goto out_label;
419 }
420 mdsk_term_io(device);
421 if (rc == 0)
422 break;
423 }
424 if (bsize > PAGE_SIZE) {
425 pr_warning("%s: Accessing the DASD failed because of an "
426 "incorrect format (rc=%d)\n",
427 dev_name(&device->cdev->dev), rc);
428 rc = -EIO;
429 goto out_label;
430 }
431 /* check for label block */
432 if (memcmp(label->label_id, DASD_DIAG_CMS1,
433 sizeof(DASD_DIAG_CMS1)) == 0) {
434 /* get formatted blocksize from label block */
435 bsize = (unsigned int) label->block_size;
436 block->blocks = (unsigned long) label->block_count;
437 } else
438 block->blocks = end_block;
439 block->bp_block = bsize;
440 block->s2b_shift = 0; /* bits to shift 512 to get a block */
441 for (sb = 512; sb < bsize; sb = sb << 1)
442 block->s2b_shift++;
443 rc = mdsk_init_io(device, block->bp_block, 0, NULL);
444 if (rc && (rc != 4)) {
445 pr_warning("%s: DIAG initialization failed with rc=%d\n",
446 dev_name(&device->cdev->dev), rc);
447 rc = -EIO;
448 } else {
449 if (rc == 4)
450 set_bit(DASD_FLAG_DEVICE_RO, &device->flags);
451 pr_info("%s: New DASD with %ld byte/block, total size %ld "
452 "KB%s\n", dev_name(&device->cdev->dev),
453 (unsigned long) block->bp_block,
454 (unsigned long) (block->blocks <<
455 block->s2b_shift) >> 1,
456 (rc == 4) ? ", read-only device" : "");
457 rc = 0;
458 }
459 out_label:
460 free_page((long) label);
461 out:
462 if (rc) {
463 device->block = NULL;
464 dasd_free_block(block);
465 device->private = NULL;
466 kfree(private);
467 }
468 return rc;
469 }
470
471 /* Fill in virtual disk geometry for device. Return zero on success, non-zero
472 * otherwise. */
473 static int
474 dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo)
475 {
476 if (dasd_check_blocksize(block->bp_block) != 0)
477 return -EINVAL;
478 geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
479 geo->heads = 16;
480 geo->sectors = 128 >> block->s2b_shift;
481 return 0;
482 }
483
484 static dasd_erp_fn_t
485 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
486 {
487 return dasd_default_erp_action;
488 }
489
490 static dasd_erp_fn_t
491 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
492 {
493 return dasd_default_erp_postaction;
494 }
495
496 /* Create DASD request from block device request. Return pointer to new
497 * request on success, ERR_PTR otherwise. */
498 static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev,
499 struct dasd_block *block,
500 struct request *req)
501 {
502 struct dasd_ccw_req *cqr;
503 struct dasd_diag_req *dreq;
504 struct dasd_diag_bio *dbio;
505 struct req_iterator iter;
506 struct bio_vec *bv;
507 char *dst;
508 unsigned int count, datasize;
509 sector_t recid, first_rec, last_rec;
510 unsigned int blksize, off;
511 unsigned char rw_cmd;
512
513 if (rq_data_dir(req) == READ)
514 rw_cmd = MDSK_READ_REQ;
515 else if (rq_data_dir(req) == WRITE)
516 rw_cmd = MDSK_WRITE_REQ;
517 else
518 return ERR_PTR(-EINVAL);
519 blksize = block->bp_block;
520 /* Calculate record id of first and last block. */
521 first_rec = blk_rq_pos(req) >> block->s2b_shift;
522 last_rec =
523 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
524 /* Check struct bio and count the number of blocks for the request. */
525 count = 0;
526 rq_for_each_segment(bv, req, iter) {
527 if (bv->bv_len & (blksize - 1))
528 /* Fba can only do full blocks. */
529 return ERR_PTR(-EINVAL);
530 count += bv->bv_len >> (block->s2b_shift + 9);
531 }
532 /* Paranoia. */
533 if (count != last_rec - first_rec + 1)
534 return ERR_PTR(-EINVAL);
535 /* Build the request */
536 datasize = sizeof(struct dasd_diag_req) +
537 count*sizeof(struct dasd_diag_bio);
538 cqr = dasd_smalloc_request(DASD_DIAG_MAGIC, 0, datasize, memdev);
539 if (IS_ERR(cqr))
540 return cqr;
541
542 dreq = (struct dasd_diag_req *) cqr->data;
543 dreq->block_count = count;
544 dbio = dreq->bio;
545 recid = first_rec;
546 rq_for_each_segment(bv, req, iter) {
547 dst = page_address(bv->bv_page) + bv->bv_offset;
548 for (off = 0; off < bv->bv_len; off += blksize) {
549 memset(dbio, 0, sizeof (struct dasd_diag_bio));
550 dbio->type = rw_cmd;
551 dbio->block_number = recid + 1;
552 dbio->buffer = dst;
553 dbio++;
554 dst += blksize;
555 recid++;
556 }
557 }
558 cqr->retries = DIAG_MAX_RETRIES;
559 cqr->buildclk = get_clock();
560 if (blk_noretry_request(req) ||
561 block->base->features & DASD_FEATURE_FAILFAST)
562 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
563 cqr->startdev = memdev;
564 cqr->memdev = memdev;
565 cqr->block = block;
566 cqr->expires = memdev->default_expires * HZ;
567 cqr->status = DASD_CQR_FILLED;
568 return cqr;
569 }
570
571 /* Release DASD request. Return non-zero if request was successful, zero
572 * otherwise. */
573 static int
574 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
575 {
576 int status;
577
578 status = cqr->status == DASD_CQR_DONE;
579 dasd_sfree_request(cqr, cqr->memdev);
580 return status;
581 }
582
583 static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr)
584 {
585 cqr->status = DASD_CQR_FILLED;
586 };
587
588 /* Fill in IOCTL data for device. */
589 static int
590 dasd_diag_fill_info(struct dasd_device * device,
591 struct dasd_information2_t * info)
592 {
593 struct dasd_diag_private *private;
594
595 private = (struct dasd_diag_private *) device->private;
596 info->label_block = (unsigned int) private->pt_block;
597 info->FBA_layout = 1;
598 info->format = DASD_FORMAT_LDL;
599 info->characteristics_size = sizeof (struct dasd_diag_characteristics);
600 memcpy(info->characteristics,
601 &((struct dasd_diag_private *) device->private)->rdc_data,
602 sizeof (struct dasd_diag_characteristics));
603 info->confdata_size = 0;
604 return 0;
605 }
606
607 static void
608 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
609 struct irb *stat)
610 {
611 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
612 "dump sense not available for DIAG data");
613 }
614
615 static struct dasd_discipline dasd_diag_discipline = {
616 .owner = THIS_MODULE,
617 .name = "DIAG",
618 .ebcname = "DIAG",
619 .max_blocks = DIAG_MAX_BLOCKS,
620 .check_device = dasd_diag_check_device,
621 .verify_path = dasd_generic_verify_path,
622 .fill_geometry = dasd_diag_fill_geometry,
623 .start_IO = dasd_start_diag,
624 .term_IO = dasd_diag_term_IO,
625 .handle_terminated_request = dasd_diag_handle_terminated_request,
626 .erp_action = dasd_diag_erp_action,
627 .erp_postaction = dasd_diag_erp_postaction,
628 .build_cp = dasd_diag_build_cp,
629 .free_cp = dasd_diag_free_cp,
630 .dump_sense = dasd_diag_dump_sense,
631 .fill_info = dasd_diag_fill_info,
632 };
633
634 static int __init
635 dasd_diag_init(void)
636 {
637 if (!MACHINE_IS_VM) {
638 pr_info("Discipline %s cannot be used without z/VM\n",
639 dasd_diag_discipline.name);
640 return -ENODEV;
641 }
642 ASCEBC(dasd_diag_discipline.ebcname, 4);
643
644 service_subclass_irq_register();
645 register_external_interrupt(0x2603, dasd_ext_handler);
646 dasd_diag_discipline_pointer = &dasd_diag_discipline;
647 return 0;
648 }
649
650 static void __exit
651 dasd_diag_cleanup(void)
652 {
653 unregister_external_interrupt(0x2603, dasd_ext_handler);
654 service_subclass_irq_unregister();
655 dasd_diag_discipline_pointer = NULL;
656 }
657
658 module_init(dasd_diag_init);
659 module_exit(dasd_diag_cleanup);