Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[wrt350n-kernel.git] / drivers / s390 / block / dasd_diag.c
blobd91df38ee4f7cb4ed418a043e689fc95126e8c7e
1 /*
2 * File...........: linux/drivers/s390/block/dasd_diag.c
3 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4 * Based on.......: linux/drivers/s390/block/mdisk.c
5 * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
6 * Bugreports.to..: <Linux390@de.ibm.com>
7 * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
9 */
11 #include <linux/stddef.h>
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/hdreg.h>
15 #include <linux/bio.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/jiffies.h>
20 #include <asm/dasd.h>
21 #include <asm/debug.h>
22 #include <asm/ebcdic.h>
23 #include <asm/io.h>
24 #include <asm/s390_ext.h>
25 #include <asm/todclk.h>
26 #include <asm/vtoc.h>
27 #include <asm/diag.h>
29 #include "dasd_int.h"
30 #include "dasd_diag.h"
32 #define PRINTK_HEADER "dasd(diag):"
34 MODULE_LICENSE("GPL");
36 /* The maximum number of blocks per request (max_blocks) is dependent on the
37 * amount of storage that is available in the static I/O buffer for each
38 * device. Currently each device gets 2 pages. We want to fit two requests
39 * into the available memory so that we can immediately start the next if one
40 * finishes. */
41 #define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \
42 sizeof(struct dasd_diag_req)) / \
43 sizeof(struct dasd_diag_bio)) / 2)
44 #define DIAG_MAX_RETRIES 32
45 #define DIAG_TIMEOUT 50 * HZ
47 static struct dasd_discipline dasd_diag_discipline;
49 struct dasd_diag_private {
50 struct dasd_diag_characteristics rdc_data;
51 struct dasd_diag_rw_io iob;
52 struct dasd_diag_init_io iib;
53 blocknum_t pt_block;
54 struct ccw_dev_id dev_id;
57 struct dasd_diag_req {
58 unsigned int block_count;
59 struct dasd_diag_bio bio[0];
62 static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */
64 /* Perform DIAG250 call with block I/O parameter list iob (input and output)
65 * and function code cmd.
66 * In case of an exception return 3. Otherwise return result of bitwise OR of
67 * resulting condition code and DIAG return code. */
68 static inline int dia250(void *iob, int cmd)
70 register unsigned long reg2 asm ("2") = (unsigned long) iob;
71 typedef union {
72 struct dasd_diag_init_io init_io;
73 struct dasd_diag_rw_io rw_io;
74 } addr_type;
75 int rc;
77 rc = 3;
78 asm volatile(
79 " diag 2,%2,0x250\n"
80 "0: ipm %0\n"
81 " srl %0,28\n"
82 " or %0,3\n"
83 "1:\n"
84 EX_TABLE(0b,1b)
85 : "+d" (rc), "=m" (*(addr_type *) iob)
86 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob)
87 : "3", "cc");
88 return rc;
91 /* Initialize block I/O to DIAG device using the specified blocksize and
92 * block offset. On success, return zero and set end_block to contain the
93 * number of blocks on the device minus the specified offset. Return non-zero
94 * otherwise. */
95 static inline int
96 mdsk_init_io(struct dasd_device *device, unsigned int blocksize,
97 blocknum_t offset, blocknum_t *end_block)
99 struct dasd_diag_private *private;
100 struct dasd_diag_init_io *iib;
101 int rc;
103 private = (struct dasd_diag_private *) device->private;
104 iib = &private->iib;
105 memset(iib, 0, sizeof (struct dasd_diag_init_io));
107 iib->dev_nr = private->dev_id.devno;
108 iib->block_size = blocksize;
109 iib->offset = offset;
110 iib->flaga = DASD_DIAG_FLAGA_DEFAULT;
112 rc = dia250(iib, INIT_BIO);
114 if ((rc & 3) == 0 && end_block)
115 *end_block = iib->end_block;
117 return rc;
120 /* Remove block I/O environment for device. Return zero on success, non-zero
121 * otherwise. */
122 static inline int
123 mdsk_term_io(struct dasd_device * device)
125 struct dasd_diag_private *private;
126 struct dasd_diag_init_io *iib;
127 int rc;
129 private = (struct dasd_diag_private *) device->private;
130 iib = &private->iib;
131 memset(iib, 0, sizeof (struct dasd_diag_init_io));
132 iib->dev_nr = private->dev_id.devno;
133 rc = dia250(iib, TERM_BIO);
134 return rc;
137 /* Error recovery for failed DIAG requests - try to reestablish the DIAG
138 * environment. */
139 static void
140 dasd_diag_erp(struct dasd_device *device)
142 int rc;
144 mdsk_term_io(device);
145 rc = mdsk_init_io(device, device->block->bp_block, 0, NULL);
146 if (rc)
147 DEV_MESSAGE(KERN_WARNING, device, "DIAG ERP unsuccessful, "
148 "rc=%d", rc);
151 /* Start a given request at the device. Return zero on success, non-zero
152 * otherwise. */
153 static int
154 dasd_start_diag(struct dasd_ccw_req * cqr)
156 struct dasd_device *device;
157 struct dasd_diag_private *private;
158 struct dasd_diag_req *dreq;
159 int rc;
161 device = cqr->startdev;
162 if (cqr->retries < 0) {
163 DEV_MESSAGE(KERN_WARNING, device, "DIAG start_IO: request %p "
164 "- no retry left)", cqr);
165 cqr->status = DASD_CQR_ERROR;
166 return -EIO;
168 private = (struct dasd_diag_private *) device->private;
169 dreq = (struct dasd_diag_req *) cqr->data;
171 private->iob.dev_nr = private->dev_id.devno;
172 private->iob.key = 0;
173 private->iob.flags = DASD_DIAG_RWFLAG_ASYNC;
174 private->iob.block_count = dreq->block_count;
175 private->iob.interrupt_params = (addr_t) cqr;
176 private->iob.bio_list = dreq->bio;
177 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
179 cqr->startclk = get_clock();
180 cqr->starttime = jiffies;
181 cqr->retries--;
183 rc = dia250(&private->iob, RW_BIO);
184 switch (rc) {
185 case 0: /* Synchronous I/O finished successfully */
186 cqr->stopclk = get_clock();
187 cqr->status = DASD_CQR_SUCCESS;
188 /* Indicate to calling function that only a dasd_schedule_bh()
189 and no timer is needed */
190 rc = -EACCES;
191 break;
192 case 8: /* Asynchronous I/O was started */
193 cqr->status = DASD_CQR_IN_IO;
194 rc = 0;
195 break;
196 default: /* Error condition */
197 cqr->status = DASD_CQR_QUEUED;
198 DEV_MESSAGE(KERN_WARNING, device, "dia250 returned rc=%d", rc);
199 dasd_diag_erp(device);
200 rc = -EIO;
201 break;
203 return rc;
206 /* Terminate given request at the device. */
207 static int
208 dasd_diag_term_IO(struct dasd_ccw_req * cqr)
210 struct dasd_device *device;
212 device = cqr->startdev;
213 mdsk_term_io(device);
214 mdsk_init_io(device, device->block->bp_block, 0, NULL);
215 cqr->status = DASD_CQR_CLEAR_PENDING;
216 cqr->stopclk = get_clock();
217 dasd_schedule_device_bh(device);
218 return 0;
221 /* Handle external interruption. */
222 static void
223 dasd_ext_handler(__u16 code)
225 struct dasd_ccw_req *cqr, *next;
226 struct dasd_device *device;
227 unsigned long long expires;
228 unsigned long flags;
229 u8 int_code, status;
230 addr_t ip;
231 int rc;
233 int_code = *((u8 *) DASD_DIAG_LC_INT_CODE);
234 status = *((u8 *) DASD_DIAG_LC_INT_STATUS);
235 switch (int_code) {
236 case DASD_DIAG_CODE_31BIT:
237 ip = (addr_t) *((u32 *) DASD_DIAG_LC_INT_PARM_31BIT);
238 break;
239 case DASD_DIAG_CODE_64BIT:
240 ip = (addr_t) *((u64 *) DASD_DIAG_LC_INT_PARM_64BIT);
241 break;
242 default:
243 return;
245 if (!ip) { /* no intparm: unsolicited interrupt */
246 MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt");
247 return;
249 cqr = (struct dasd_ccw_req *) ip;
250 device = (struct dasd_device *) cqr->startdev;
251 if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
252 DEV_MESSAGE(KERN_WARNING, device,
253 " magic number of dasd_ccw_req 0x%08X doesn't"
254 " match discipline 0x%08X",
255 cqr->magic, *(int *) (&device->discipline->name));
256 return;
259 /* get irq lock to modify request queue */
260 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
262 /* Check for a pending clear operation */
263 if (cqr->status == DASD_CQR_CLEAR_PENDING) {
264 cqr->status = DASD_CQR_CLEARED;
265 dasd_device_clear_timer(device);
266 dasd_schedule_device_bh(device);
267 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
268 return;
271 cqr->stopclk = get_clock();
273 expires = 0;
274 if (status == 0) {
275 cqr->status = DASD_CQR_SUCCESS;
276 /* Start first request on queue if possible -> fast_io. */
277 if (!list_empty(&device->ccw_queue)) {
278 next = list_entry(device->ccw_queue.next,
279 struct dasd_ccw_req, devlist);
280 if (next->status == DASD_CQR_QUEUED) {
281 rc = dasd_start_diag(next);
282 if (rc == 0)
283 expires = next->expires;
284 else if (rc != -EACCES)
285 DEV_MESSAGE(KERN_WARNING, device, "%s",
286 "Interrupt fastpath "
287 "failed!");
290 } else {
291 cqr->status = DASD_CQR_QUEUED;
292 DEV_MESSAGE(KERN_WARNING, device, "interrupt status for "
293 "request %p was %d (%d retries left)", cqr, status,
294 cqr->retries);
295 dasd_diag_erp(device);
298 if (expires != 0)
299 dasd_device_set_timer(device, expires);
300 else
301 dasd_device_clear_timer(device);
302 dasd_schedule_device_bh(device);
304 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
307 /* Check whether device can be controlled by DIAG discipline. Return zero on
308 * success, non-zero otherwise. */
309 static int
310 dasd_diag_check_device(struct dasd_device *device)
312 struct dasd_block *block;
313 struct dasd_diag_private *private;
314 struct dasd_diag_characteristics *rdc_data;
315 struct dasd_diag_bio bio;
316 struct vtoc_cms_label *label;
317 blocknum_t end_block;
318 unsigned int sb, bsize;
319 int rc;
321 private = (struct dasd_diag_private *) device->private;
322 if (private == NULL) {
323 private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
324 if (private == NULL) {
325 DEV_MESSAGE(KERN_WARNING, device, "%s",
326 "memory allocation failed for private data");
327 return -ENOMEM;
329 ccw_device_get_id(device->cdev, &private->dev_id);
330 device->private = (void *) private;
332 block = dasd_alloc_block();
333 if (IS_ERR(block)) {
334 DEV_MESSAGE(KERN_WARNING, device, "%s",
335 "could not allocate dasd block structure");
336 kfree(device->private);
337 return PTR_ERR(block);
339 device->block = block;
340 block->base = device;
342 /* Read Device Characteristics */
343 rdc_data = (void *) &(private->rdc_data);
344 rdc_data->dev_nr = private->dev_id.devno;
345 rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
347 rc = diag210((struct diag210 *) rdc_data);
348 if (rc) {
349 DEV_MESSAGE(KERN_WARNING, device, "failed to retrieve device "
350 "information (rc=%d)", rc);
351 return -ENOTSUPP;
354 /* Figure out position of label block */
355 switch (private->rdc_data.vdev_class) {
356 case DEV_CLASS_FBA:
357 private->pt_block = 1;
358 break;
359 case DEV_CLASS_ECKD:
360 private->pt_block = 2;
361 break;
362 default:
363 DEV_MESSAGE(KERN_WARNING, device, "unsupported device class "
364 "(class=%d)", private->rdc_data.vdev_class);
365 return -ENOTSUPP;
368 DBF_DEV_EVENT(DBF_INFO, device,
369 "%04X: %04X on real %04X/%02X",
370 rdc_data->dev_nr,
371 rdc_data->vdev_type,
372 rdc_data->rdev_type, rdc_data->rdev_model);
374 /* terminate all outstanding operations */
375 mdsk_term_io(device);
377 /* figure out blocksize of device */
378 label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL);
379 if (label == NULL) {
380 DEV_MESSAGE(KERN_WARNING, device, "%s",
381 "No memory to allocate initialization request");
382 return -ENOMEM;
384 rc = 0;
385 end_block = 0;
386 /* try all sizes - needed for ECKD devices */
387 for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
388 mdsk_init_io(device, bsize, 0, &end_block);
389 memset(&bio, 0, sizeof (struct dasd_diag_bio));
390 bio.type = MDSK_READ_REQ;
391 bio.block_number = private->pt_block + 1;
392 bio.buffer = label;
393 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
394 private->iob.dev_nr = rdc_data->dev_nr;
395 private->iob.key = 0;
396 private->iob.flags = 0; /* do synchronous io */
397 private->iob.block_count = 1;
398 private->iob.interrupt_params = 0;
399 private->iob.bio_list = &bio;
400 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
401 rc = dia250(&private->iob, RW_BIO);
402 if (rc == 3) {
403 DEV_MESSAGE(KERN_WARNING, device, "%s",
404 "DIAG call failed");
405 rc = -EOPNOTSUPP;
406 goto out;
408 mdsk_term_io(device);
409 if (rc == 0)
410 break;
412 if (bsize > PAGE_SIZE) {
413 DEV_MESSAGE(KERN_WARNING, device, "device access failed "
414 "(rc=%d)", rc);
415 rc = -EIO;
416 goto out;
418 /* check for label block */
419 if (memcmp(label->label_id, DASD_DIAG_CMS1,
420 sizeof(DASD_DIAG_CMS1)) == 0) {
421 /* get formatted blocksize from label block */
422 bsize = (unsigned int) label->block_size;
423 block->blocks = (unsigned long) label->block_count;
424 } else
425 block->blocks = end_block;
426 block->bp_block = bsize;
427 block->s2b_shift = 0; /* bits to shift 512 to get a block */
428 for (sb = 512; sb < bsize; sb = sb << 1)
429 block->s2b_shift++;
430 rc = mdsk_init_io(device, block->bp_block, 0, NULL);
431 if (rc) {
432 DEV_MESSAGE(KERN_WARNING, device, "DIAG initialization "
433 "failed (rc=%d)", rc);
434 rc = -EIO;
435 } else {
436 DEV_MESSAGE(KERN_INFO, device,
437 "(%ld B/blk): %ldkB",
438 (unsigned long) block->bp_block,
439 (unsigned long) (block->blocks <<
440 block->s2b_shift) >> 1);
442 out:
443 free_page((long) label);
444 return rc;
447 /* Fill in virtual disk geometry for device. Return zero on success, non-zero
448 * otherwise. */
449 static int
450 dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo)
452 if (dasd_check_blocksize(block->bp_block) != 0)
453 return -EINVAL;
454 geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
455 geo->heads = 16;
456 geo->sectors = 128 >> block->s2b_shift;
457 return 0;
460 static dasd_erp_fn_t
461 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
463 return dasd_default_erp_action;
466 static dasd_erp_fn_t
467 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
469 return dasd_default_erp_postaction;
472 /* Create DASD request from block device request. Return pointer to new
473 * request on success, ERR_PTR otherwise. */
474 static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev,
475 struct dasd_block *block,
476 struct request *req)
478 struct dasd_ccw_req *cqr;
479 struct dasd_diag_req *dreq;
480 struct dasd_diag_bio *dbio;
481 struct req_iterator iter;
482 struct bio_vec *bv;
483 char *dst;
484 unsigned int count, datasize;
485 sector_t recid, first_rec, last_rec;
486 unsigned int blksize, off;
487 unsigned char rw_cmd;
489 if (rq_data_dir(req) == READ)
490 rw_cmd = MDSK_READ_REQ;
491 else if (rq_data_dir(req) == WRITE)
492 rw_cmd = MDSK_WRITE_REQ;
493 else
494 return ERR_PTR(-EINVAL);
495 blksize = block->bp_block;
496 /* Calculate record id of first and last block. */
497 first_rec = req->sector >> block->s2b_shift;
498 last_rec = (req->sector + req->nr_sectors - 1) >> block->s2b_shift;
499 /* Check struct bio and count the number of blocks for the request. */
500 count = 0;
501 rq_for_each_segment(bv, req, iter) {
502 if (bv->bv_len & (blksize - 1))
503 /* Fba can only do full blocks. */
504 return ERR_PTR(-EINVAL);
505 count += bv->bv_len >> (block->s2b_shift + 9);
507 /* Paranoia. */
508 if (count != last_rec - first_rec + 1)
509 return ERR_PTR(-EINVAL);
510 /* Build the request */
511 datasize = sizeof(struct dasd_diag_req) +
512 count*sizeof(struct dasd_diag_bio);
513 cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0,
514 datasize, memdev);
515 if (IS_ERR(cqr))
516 return cqr;
518 dreq = (struct dasd_diag_req *) cqr->data;
519 dreq->block_count = count;
520 dbio = dreq->bio;
521 recid = first_rec;
522 rq_for_each_segment(bv, req, iter) {
523 dst = page_address(bv->bv_page) + bv->bv_offset;
524 for (off = 0; off < bv->bv_len; off += blksize) {
525 memset(dbio, 0, sizeof (struct dasd_diag_bio));
526 dbio->type = rw_cmd;
527 dbio->block_number = recid + 1;
528 dbio->buffer = dst;
529 dbio++;
530 dst += blksize;
531 recid++;
534 cqr->retries = DIAG_MAX_RETRIES;
535 cqr->buildclk = get_clock();
536 if (req->cmd_flags & REQ_FAILFAST)
537 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
538 cqr->startdev = memdev;
539 cqr->memdev = memdev;
540 cqr->block = block;
541 cqr->expires = DIAG_TIMEOUT;
542 cqr->status = DASD_CQR_FILLED;
543 return cqr;
546 /* Release DASD request. Return non-zero if request was successful, zero
547 * otherwise. */
548 static int
549 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
551 int status;
553 status = cqr->status == DASD_CQR_DONE;
554 dasd_sfree_request(cqr, cqr->memdev);
555 return status;
558 static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr)
560 cqr->status = DASD_CQR_FILLED;
563 /* Fill in IOCTL data for device. */
564 static int
565 dasd_diag_fill_info(struct dasd_device * device,
566 struct dasd_information2_t * info)
568 struct dasd_diag_private *private;
570 private = (struct dasd_diag_private *) device->private;
571 info->label_block = (unsigned int) private->pt_block;
572 info->FBA_layout = 1;
573 info->format = DASD_FORMAT_LDL;
574 info->characteristics_size = sizeof (struct dasd_diag_characteristics);
575 memcpy(info->characteristics,
576 &((struct dasd_diag_private *) device->private)->rdc_data,
577 sizeof (struct dasd_diag_characteristics));
578 info->confdata_size = 0;
579 return 0;
582 static void
583 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
584 struct irb *stat)
586 DEV_MESSAGE(KERN_ERR, device, "%s",
587 "dump sense not available for DIAG data");
590 static struct dasd_discipline dasd_diag_discipline = {
591 .owner = THIS_MODULE,
592 .name = "DIAG",
593 .ebcname = "DIAG",
594 .max_blocks = DIAG_MAX_BLOCKS,
595 .check_device = dasd_diag_check_device,
596 .fill_geometry = dasd_diag_fill_geometry,
597 .start_IO = dasd_start_diag,
598 .term_IO = dasd_diag_term_IO,
599 .handle_terminated_request = dasd_diag_handle_terminated_request,
600 .erp_action = dasd_diag_erp_action,
601 .erp_postaction = dasd_diag_erp_postaction,
602 .build_cp = dasd_diag_build_cp,
603 .free_cp = dasd_diag_free_cp,
604 .dump_sense = dasd_diag_dump_sense,
605 .fill_info = dasd_diag_fill_info,
608 static int __init
609 dasd_diag_init(void)
611 if (!MACHINE_IS_VM) {
612 MESSAGE_LOG(KERN_INFO,
613 "Machine is not VM: %s "
614 "discipline not initializing",
615 dasd_diag_discipline.name);
616 return -ENODEV;
618 ASCEBC(dasd_diag_discipline.ebcname, 4);
620 ctl_set_bit(0, 9);
621 register_external_interrupt(0x2603, dasd_ext_handler);
622 dasd_diag_discipline_pointer = &dasd_diag_discipline;
623 return 0;
626 static void __exit
627 dasd_diag_cleanup(void)
629 unregister_external_interrupt(0x2603, dasd_ext_handler);
630 ctl_clear_bit(0, 9);
631 dasd_diag_discipline_pointer = NULL;
634 module_init(dasd_diag_init);
635 module_exit(dasd_diag_cleanup);