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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/scsi/sd.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/scsi/sd.c')
-rw-r--r--drivers/scsi/sd.c1740
1 files changed, 1740 insertions, 0 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
new file mode 100644
index 000000000000..19afb25e44d3
--- /dev/null
+++ b/drivers/scsi/sd.c
@@ -0,0 +1,1740 @@
1/*
2 * sd.c Copyright (C) 1992 Drew Eckhardt
3 * Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
4 *
5 * Linux scsi disk driver
6 * Initial versions: Drew Eckhardt
7 * Subsequent revisions: Eric Youngdale
8 * Modification history:
9 * - Drew Eckhardt <drew@colorado.edu> original
10 * - Eric Youngdale <eric@andante.org> add scatter-gather, multiple
11 * outstanding request, and other enhancements.
12 * Support loadable low-level scsi drivers.
13 * - Jirka Hanika <geo@ff.cuni.cz> support more scsi disks using
14 * eight major numbers.
15 * - Richard Gooch <rgooch@atnf.csiro.au> support devfs.
16 * - Torben Mathiasen <tmm@image.dk> Resource allocation fixes in
17 * sd_init and cleanups.
18 * - Alex Davis <letmein@erols.com> Fix problem where partition info
19 * not being read in sd_open. Fix problem where removable media
20 * could be ejected after sd_open.
21 * - Douglas Gilbert <dgilbert@interlog.com> cleanup for lk 2.5.x
22 * - Badari Pulavarty <pbadari@us.ibm.com>, Matthew Wilcox
23 * <willy@debian.org>, Kurt Garloff <garloff@suse.de>:
24 * Support 32k/1M disks.
25 *
26 * Logging policy (needs CONFIG_SCSI_LOGGING defined):
27 * - setting up transfer: SCSI_LOG_HLQUEUE levels 1 and 2
28 * - end of transfer (bh + scsi_lib): SCSI_LOG_HLCOMPLETE level 1
29 * - entering sd_ioctl: SCSI_LOG_IOCTL level 1
30 * - entering other commands: SCSI_LOG_HLQUEUE level 3
31 * Note: when the logging level is set by the user, it must be greater
32 * than the level indicated above to trigger output.
33 */
34
35#include <linux/config.h>
36#include <linux/module.h>
37#include <linux/fs.h>
38#include <linux/kernel.h>
39#include <linux/sched.h>
40#include <linux/mm.h>
41#include <linux/bio.h>
42#include <linux/genhd.h>
43#include <linux/hdreg.h>
44#include <linux/errno.h>
45#include <linux/idr.h>
46#include <linux/interrupt.h>
47#include <linux/init.h>
48#include <linux/blkdev.h>
49#include <linux/blkpg.h>
50#include <linux/kref.h>
51#include <linux/delay.h>
52#include <asm/uaccess.h>
53
54#include <scsi/scsi.h>
55#include <scsi/scsi_cmnd.h>
56#include <scsi/scsi_dbg.h>
57#include <scsi/scsi_device.h>
58#include <scsi/scsi_driver.h>
59#include <scsi/scsi_eh.h>
60#include <scsi/scsi_host.h>
61#include <scsi/scsi_ioctl.h>
62#include <scsi/scsi_request.h>
63#include <scsi/scsicam.h>
64
65#include "scsi_logging.h"
66
67/*
68 * More than enough for everybody ;) The huge number of majors
69 * is a leftover from 16bit dev_t days, we don't really need that
70 * much numberspace.
71 */
72#define SD_MAJORS 16
73
74/*
75 * This is limited by the naming scheme enforced in sd_probe,
76 * add another character to it if you really need more disks.
77 */
78#define SD_MAX_DISKS (((26 * 26) + 26 + 1) * 26)
79
80/*
81 * Time out in seconds for disks and Magneto-opticals (which are slower).
82 */
83#define SD_TIMEOUT (30 * HZ)
84#define SD_MOD_TIMEOUT (75 * HZ)
85
86/*
87 * Number of allowed retries
88 */
89#define SD_MAX_RETRIES 5
90#define SD_PASSTHROUGH_RETRIES 1
91
92static void scsi_disk_release(struct kref *kref);
93
94struct scsi_disk {
95 struct scsi_driver *driver; /* always &sd_template */
96 struct scsi_device *device;
97 struct kref kref;
98 struct gendisk *disk;
99 unsigned int openers; /* protected by BKL for now, yuck */
100 sector_t capacity; /* size in 512-byte sectors */
101 u32 index;
102 u8 media_present;
103 u8 write_prot;
104 unsigned WCE : 1; /* state of disk WCE bit */
105 unsigned RCD : 1; /* state of disk RCD bit, unused */
106};
107
108static DEFINE_IDR(sd_index_idr);
109static DEFINE_SPINLOCK(sd_index_lock);
110
111/* This semaphore is used to mediate the 0->1 reference get in the
112 * face of object destruction (i.e. we can't allow a get on an
113 * object after last put) */
114static DECLARE_MUTEX(sd_ref_sem);
115
116static int sd_revalidate_disk(struct gendisk *disk);
117static void sd_rw_intr(struct scsi_cmnd * SCpnt);
118
119static int sd_probe(struct device *);
120static int sd_remove(struct device *);
121static void sd_shutdown(struct device *dev);
122static void sd_rescan(struct device *);
123static int sd_init_command(struct scsi_cmnd *);
124static int sd_issue_flush(struct device *, sector_t *);
125static void sd_end_flush(request_queue_t *, struct request *);
126static int sd_prepare_flush(request_queue_t *, struct request *);
127static void sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
128 struct scsi_request *SRpnt, unsigned char *buffer);
129
130static struct scsi_driver sd_template = {
131 .owner = THIS_MODULE,
132 .gendrv = {
133 .name = "sd",
134 .probe = sd_probe,
135 .remove = sd_remove,
136 .shutdown = sd_shutdown,
137 },
138 .rescan = sd_rescan,
139 .init_command = sd_init_command,
140 .issue_flush = sd_issue_flush,
141 .prepare_flush = sd_prepare_flush,
142 .end_flush = sd_end_flush,
143};
144
145/*
146 * Device no to disk mapping:
147 *
148 * major disc2 disc p1
149 * |............|.............|....|....| <- dev_t
150 * 31 20 19 8 7 4 3 0
151 *
152 * Inside a major, we have 16k disks, however mapped non-
153 * contiguously. The first 16 disks are for major0, the next
154 * ones with major1, ... Disk 256 is for major0 again, disk 272
155 * for major1, ...
156 * As we stay compatible with our numbering scheme, we can reuse
157 * the well-know SCSI majors 8, 65--71, 136--143.
158 */
159static int sd_major(int major_idx)
160{
161 switch (major_idx) {
162 case 0:
163 return SCSI_DISK0_MAJOR;
164 case 1 ... 7:
165 return SCSI_DISK1_MAJOR + major_idx - 1;
166 case 8 ... 15:
167 return SCSI_DISK8_MAJOR + major_idx - 8;
168 default:
169 BUG();
170 return 0; /* shut up gcc */
171 }
172}
173
174#define to_scsi_disk(obj) container_of(obj,struct scsi_disk,kref)
175
176static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
177{
178 return container_of(disk->private_data, struct scsi_disk, driver);
179}
180
181static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
182{
183 struct scsi_disk *sdkp = NULL;
184
185 down(&sd_ref_sem);
186 if (disk->private_data == NULL)
187 goto out;
188 sdkp = scsi_disk(disk);
189 kref_get(&sdkp->kref);
190 if (scsi_device_get(sdkp->device))
191 goto out_put;
192 up(&sd_ref_sem);
193 return sdkp;
194
195 out_put:
196 kref_put(&sdkp->kref, scsi_disk_release);
197 sdkp = NULL;
198 out:
199 up(&sd_ref_sem);
200 return sdkp;
201}
202
203static void scsi_disk_put(struct scsi_disk *sdkp)
204{
205 struct scsi_device *sdev = sdkp->device;
206
207 down(&sd_ref_sem);
208 kref_put(&sdkp->kref, scsi_disk_release);
209 scsi_device_put(sdev);
210 up(&sd_ref_sem);
211}
212
213/**
214 * sd_init_command - build a scsi (read or write) command from
215 * information in the request structure.
216 * @SCpnt: pointer to mid-level's per scsi command structure that
217 * contains request and into which the scsi command is written
218 *
219 * Returns 1 if successful and 0 if error (or cannot be done now).
220 **/
221static int sd_init_command(struct scsi_cmnd * SCpnt)
222{
223 unsigned int this_count, timeout;
224 struct gendisk *disk;
225 sector_t block;
226 struct scsi_device *sdp = SCpnt->device;
227 struct request *rq = SCpnt->request;
228
229 timeout = sdp->timeout;
230
231 /*
232 * SG_IO from block layer already setup, just copy cdb basically
233 */
234 if (blk_pc_request(rq)) {
235 if (sizeof(rq->cmd) > sizeof(SCpnt->cmnd))
236 return 0;
237
238 memcpy(SCpnt->cmnd, rq->cmd, sizeof(SCpnt->cmnd));
239 if (rq_data_dir(rq) == WRITE)
240 SCpnt->sc_data_direction = DMA_TO_DEVICE;
241 else if (rq->data_len)
242 SCpnt->sc_data_direction = DMA_FROM_DEVICE;
243 else
244 SCpnt->sc_data_direction = DMA_NONE;
245
246 this_count = rq->data_len;
247 if (rq->timeout)
248 timeout = rq->timeout;
249
250 SCpnt->transfersize = rq->data_len;
251 SCpnt->allowed = SD_PASSTHROUGH_RETRIES;
252 goto queue;
253 }
254
255 /*
256 * we only do REQ_CMD and REQ_BLOCK_PC
257 */
258 if (!blk_fs_request(rq))
259 return 0;
260
261 disk = rq->rq_disk;
262 block = rq->sector;
263 this_count = SCpnt->request_bufflen >> 9;
264
265 SCSI_LOG_HLQUEUE(1, printk("sd_init_command: disk=%s, block=%llu, "
266 "count=%d\n", disk->disk_name,
267 (unsigned long long)block, this_count));
268
269 if (!sdp || !scsi_device_online(sdp) ||
270 block + rq->nr_sectors > get_capacity(disk)) {
271 SCSI_LOG_HLQUEUE(2, printk("Finishing %ld sectors\n",
272 rq->nr_sectors));
273 SCSI_LOG_HLQUEUE(2, printk("Retry with 0x%p\n", SCpnt));
274 return 0;
275 }
276
277 if (sdp->changed) {
278 /*
279 * quietly refuse to do anything to a changed disc until
280 * the changed bit has been reset
281 */
282 /* printk("SCSI disk has been changed. Prohibiting further I/O.\n"); */
283 return 0;
284 }
285 SCSI_LOG_HLQUEUE(2, printk("%s : block=%llu\n",
286 disk->disk_name, (unsigned long long)block));
287
288 /*
289 * If we have a 1K hardware sectorsize, prevent access to single
290 * 512 byte sectors. In theory we could handle this - in fact
291 * the scsi cdrom driver must be able to handle this because
292 * we typically use 1K blocksizes, and cdroms typically have
293 * 2K hardware sectorsizes. Of course, things are simpler
294 * with the cdrom, since it is read-only. For performance
295 * reasons, the filesystems should be able to handle this
296 * and not force the scsi disk driver to use bounce buffers
297 * for this.
298 */
299 if (sdp->sector_size == 1024) {
300 if ((block & 1) || (rq->nr_sectors & 1)) {
301 printk(KERN_ERR "sd: Bad block number requested");
302 return 0;
303 } else {
304 block = block >> 1;
305 this_count = this_count >> 1;
306 }
307 }
308 if (sdp->sector_size == 2048) {
309 if ((block & 3) || (rq->nr_sectors & 3)) {
310 printk(KERN_ERR "sd: Bad block number requested");
311 return 0;
312 } else {
313 block = block >> 2;
314 this_count = this_count >> 2;
315 }
316 }
317 if (sdp->sector_size == 4096) {
318 if ((block & 7) || (rq->nr_sectors & 7)) {
319 printk(KERN_ERR "sd: Bad block number requested");
320 return 0;
321 } else {
322 block = block >> 3;
323 this_count = this_count >> 3;
324 }
325 }
326 if (rq_data_dir(rq) == WRITE) {
327 if (!sdp->writeable) {
328 return 0;
329 }
330 SCpnt->cmnd[0] = WRITE_6;
331 SCpnt->sc_data_direction = DMA_TO_DEVICE;
332 } else if (rq_data_dir(rq) == READ) {
333 SCpnt->cmnd[0] = READ_6;
334 SCpnt->sc_data_direction = DMA_FROM_DEVICE;
335 } else {
336 printk(KERN_ERR "sd: Unknown command %lx\n", rq->flags);
337/* overkill panic("Unknown sd command %lx\n", rq->flags); */
338 return 0;
339 }
340
341 SCSI_LOG_HLQUEUE(2, printk("%s : %s %d/%ld 512 byte blocks.\n",
342 disk->disk_name, (rq_data_dir(rq) == WRITE) ?
343 "writing" : "reading", this_count, rq->nr_sectors));
344
345 SCpnt->cmnd[1] = 0;
346
347 if (block > 0xffffffff) {
348 SCpnt->cmnd[0] += READ_16 - READ_6;
349 SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
350 SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
351 SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
352 SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
353 SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
354 SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
355 SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
356 SCpnt->cmnd[9] = (unsigned char) block & 0xff;
357 SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
358 SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
359 SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
360 SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
361 SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
362 } else if ((this_count > 0xff) || (block > 0x1fffff) ||
363 SCpnt->device->use_10_for_rw) {
364 if (this_count > 0xffff)
365 this_count = 0xffff;
366
367 SCpnt->cmnd[0] += READ_10 - READ_6;
368 SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
369 SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
370 SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
371 SCpnt->cmnd[5] = (unsigned char) block & 0xff;
372 SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
373 SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
374 SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
375 } else {
376 if (this_count > 0xff)
377 this_count = 0xff;
378
379 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
380 SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
381 SCpnt->cmnd[3] = (unsigned char) block & 0xff;
382 SCpnt->cmnd[4] = (unsigned char) this_count;
383 SCpnt->cmnd[5] = 0;
384 }
385 SCpnt->request_bufflen = SCpnt->bufflen =
386 this_count * sdp->sector_size;
387
388 /*
389 * We shouldn't disconnect in the middle of a sector, so with a dumb
390 * host adapter, it's safe to assume that we can at least transfer
391 * this many bytes between each connect / disconnect.
392 */
393 SCpnt->transfersize = sdp->sector_size;
394 SCpnt->underflow = this_count << 9;
395 SCpnt->allowed = SD_MAX_RETRIES;
396
397queue:
398 SCpnt->timeout_per_command = timeout;
399
400 /*
401 * This is the completion routine we use. This is matched in terms
402 * of capability to this function.
403 */
404 SCpnt->done = sd_rw_intr;
405
406 /*
407 * This indicates that the command is ready from our end to be
408 * queued.
409 */
410 return 1;
411}
412
413/**
414 * sd_open - open a scsi disk device
415 * @inode: only i_rdev member may be used
416 * @filp: only f_mode and f_flags may be used
417 *
418 * Returns 0 if successful. Returns a negated errno value in case
419 * of error.
420 *
421 * Note: This can be called from a user context (e.g. fsck(1) )
422 * or from within the kernel (e.g. as a result of a mount(1) ).
423 * In the latter case @inode and @filp carry an abridged amount
424 * of information as noted above.
425 **/
426static int sd_open(struct inode *inode, struct file *filp)
427{
428 struct gendisk *disk = inode->i_bdev->bd_disk;
429 struct scsi_disk *sdkp;
430 struct scsi_device *sdev;
431 int retval;
432
433 if (!(sdkp = scsi_disk_get(disk)))
434 return -ENXIO;
435
436
437 SCSI_LOG_HLQUEUE(3, printk("sd_open: disk=%s\n", disk->disk_name));
438
439 sdev = sdkp->device;
440
441 /*
442 * If the device is in error recovery, wait until it is done.
443 * If the device is offline, then disallow any access to it.
444 */
445 retval = -ENXIO;
446 if (!scsi_block_when_processing_errors(sdev))
447 goto error_out;
448
449 if (sdev->removable || sdkp->write_prot)
450 check_disk_change(inode->i_bdev);
451
452 /*
453 * If the drive is empty, just let the open fail.
454 */
455 retval = -ENOMEDIUM;
456 if (sdev->removable && !sdkp->media_present &&
457 !(filp->f_flags & O_NDELAY))
458 goto error_out;
459
460 /*
461 * If the device has the write protect tab set, have the open fail
462 * if the user expects to be able to write to the thing.
463 */
464 retval = -EROFS;
465 if (sdkp->write_prot && (filp->f_mode & FMODE_WRITE))
466 goto error_out;
467
468 /*
469 * It is possible that the disk changing stuff resulted in
470 * the device being taken offline. If this is the case,
471 * report this to the user, and don't pretend that the
472 * open actually succeeded.
473 */
474 retval = -ENXIO;
475 if (!scsi_device_online(sdev))
476 goto error_out;
477
478 if (!sdkp->openers++ && sdev->removable) {
479 if (scsi_block_when_processing_errors(sdev))
480 scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
481 }
482
483 return 0;
484
485error_out:
486 scsi_disk_put(sdkp);
487 return retval;
488}
489
490/**
491 * sd_release - invoked when the (last) close(2) is called on this
492 * scsi disk.
493 * @inode: only i_rdev member may be used
494 * @filp: only f_mode and f_flags may be used
495 *
496 * Returns 0.
497 *
498 * Note: may block (uninterruptible) if error recovery is underway
499 * on this disk.
500 **/
501static int sd_release(struct inode *inode, struct file *filp)
502{
503 struct gendisk *disk = inode->i_bdev->bd_disk;
504 struct scsi_disk *sdkp = scsi_disk(disk);
505 struct scsi_device *sdev = sdkp->device;
506
507 SCSI_LOG_HLQUEUE(3, printk("sd_release: disk=%s\n", disk->disk_name));
508
509 if (!--sdkp->openers && sdev->removable) {
510 if (scsi_block_when_processing_errors(sdev))
511 scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
512 }
513
514 /*
515 * XXX and what if there are packets in flight and this close()
516 * XXX is followed by a "rmmod sd_mod"?
517 */
518 scsi_disk_put(sdkp);
519 return 0;
520}
521
522static int sd_hdio_getgeo(struct block_device *bdev, struct hd_geometry __user *loc)
523{
524 struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
525 struct scsi_device *sdp = sdkp->device;
526 struct Scsi_Host *host = sdp->host;
527 int diskinfo[4];
528
529 /* default to most commonly used values */
530 diskinfo[0] = 0x40; /* 1 << 6 */
531 diskinfo[1] = 0x20; /* 1 << 5 */
532 diskinfo[2] = sdkp->capacity >> 11;
533
534 /* override with calculated, extended default, or driver values */
535 if (host->hostt->bios_param)
536 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
537 else
538 scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
539
540 if (put_user(diskinfo[0], &loc->heads))
541 return -EFAULT;
542 if (put_user(diskinfo[1], &loc->sectors))
543 return -EFAULT;
544 if (put_user(diskinfo[2], &loc->cylinders))
545 return -EFAULT;
546 if (put_user((unsigned)get_start_sect(bdev),
547 (unsigned long __user *)&loc->start))
548 return -EFAULT;
549 return 0;
550}
551
552/**
553 * sd_ioctl - process an ioctl
554 * @inode: only i_rdev/i_bdev members may be used
555 * @filp: only f_mode and f_flags may be used
556 * @cmd: ioctl command number
557 * @arg: this is third argument given to ioctl(2) system call.
558 * Often contains a pointer.
559 *
560 * Returns 0 if successful (some ioctls return postive numbers on
561 * success as well). Returns a negated errno value in case of error.
562 *
563 * Note: most ioctls are forward onto the block subsystem or further
564 * down in the scsi subsytem.
565 **/
566static int sd_ioctl(struct inode * inode, struct file * filp,
567 unsigned int cmd, unsigned long arg)
568{
569 struct block_device *bdev = inode->i_bdev;
570 struct gendisk *disk = bdev->bd_disk;
571 struct scsi_device *sdp = scsi_disk(disk)->device;
572 void __user *p = (void __user *)arg;
573 int error;
574
575 SCSI_LOG_IOCTL(1, printk("sd_ioctl: disk=%s, cmd=0x%x\n",
576 disk->disk_name, cmd));
577
578 /*
579 * If we are in the middle of error recovery, don't let anyone
580 * else try and use this device. Also, if error recovery fails, it
581 * may try and take the device offline, in which case all further
582 * access to the device is prohibited.
583 */
584 error = scsi_nonblockable_ioctl(sdp, cmd, p, filp);
585 if (!scsi_block_when_processing_errors(sdp) || !error)
586 return error;
587
588 if (cmd == HDIO_GETGEO) {
589 if (!arg)
590 return -EINVAL;
591 return sd_hdio_getgeo(bdev, p);
592 }
593
594 /*
595 * Send SCSI addressing ioctls directly to mid level, send other
596 * ioctls to block level and then onto mid level if they can't be
597 * resolved.
598 */
599 switch (cmd) {
600 case SCSI_IOCTL_GET_IDLUN:
601 case SCSI_IOCTL_GET_BUS_NUMBER:
602 return scsi_ioctl(sdp, cmd, p);
603 default:
604 error = scsi_cmd_ioctl(filp, disk, cmd, p);
605 if (error != -ENOTTY)
606 return error;
607 }
608 return scsi_ioctl(sdp, cmd, p);
609}
610
611static void set_media_not_present(struct scsi_disk *sdkp)
612{
613 sdkp->media_present = 0;
614 sdkp->capacity = 0;
615 sdkp->device->changed = 1;
616}
617
618/**
619 * sd_media_changed - check if our medium changed
620 * @disk: kernel device descriptor
621 *
622 * Returns 0 if not applicable or no change; 1 if change
623 *
624 * Note: this function is invoked from the block subsystem.
625 **/
626static int sd_media_changed(struct gendisk *disk)
627{
628 struct scsi_disk *sdkp = scsi_disk(disk);
629 struct scsi_device *sdp = sdkp->device;
630 int retval;
631
632 SCSI_LOG_HLQUEUE(3, printk("sd_media_changed: disk=%s\n",
633 disk->disk_name));
634
635 if (!sdp->removable)
636 return 0;
637
638 /*
639 * If the device is offline, don't send any commands - just pretend as
640 * if the command failed. If the device ever comes back online, we
641 * can deal with it then. It is only because of unrecoverable errors
642 * that we would ever take a device offline in the first place.
643 */
644 if (!scsi_device_online(sdp))
645 goto not_present;
646
647 /*
648 * Using TEST_UNIT_READY enables differentiation between drive with
649 * no cartridge loaded - NOT READY, drive with changed cartridge -
650 * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
651 *
652 * Drives that auto spin down. eg iomega jaz 1G, will be started
653 * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
654 * sd_revalidate() is called.
655 */
656 retval = -ENODEV;
657 if (scsi_block_when_processing_errors(sdp))
658 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES);
659
660 /*
661 * Unable to test, unit probably not ready. This usually
662 * means there is no disc in the drive. Mark as changed,
663 * and we will figure it out later once the drive is
664 * available again.
665 */
666 if (retval)
667 goto not_present;
668
669 /*
670 * For removable scsi disk we have to recognise the presence
671 * of a disk in the drive. This is kept in the struct scsi_disk
672 * struct and tested at open ! Daniel Roche (dan@lectra.fr)
673 */
674 sdkp->media_present = 1;
675
676 retval = sdp->changed;
677 sdp->changed = 0;
678
679 return retval;
680
681not_present:
682 set_media_not_present(sdkp);
683 return 1;
684}
685
686static int sd_sync_cache(struct scsi_device *sdp)
687{
688 struct scsi_request *sreq;
689 int retries, res;
690
691 if (!scsi_device_online(sdp))
692 return -ENODEV;
693
694 sreq = scsi_allocate_request(sdp, GFP_KERNEL);
695 if (!sreq) {
696 printk("FAILED\n No memory for request\n");
697 return -ENOMEM;
698 }
699
700 sreq->sr_data_direction = DMA_NONE;
701 for (retries = 3; retries > 0; --retries) {
702 unsigned char cmd[10] = { 0 };
703
704 cmd[0] = SYNCHRONIZE_CACHE;
705 /*
706 * Leave the rest of the command zero to indicate
707 * flush everything.
708 */
709 scsi_wait_req(sreq, cmd, NULL, 0, SD_TIMEOUT, SD_MAX_RETRIES);
710 if (sreq->sr_result == 0)
711 break;
712 }
713
714 res = sreq->sr_result;
715 if (res) {
716 printk(KERN_WARNING "FAILED\n status = %x, message = %02x, "
717 "host = %d, driver = %02x\n ",
718 status_byte(res), msg_byte(res),
719 host_byte(res), driver_byte(res));
720 if (driver_byte(res) & DRIVER_SENSE)
721 scsi_print_req_sense("sd", sreq);
722 }
723
724 scsi_release_request(sreq);
725 return res;
726}
727
728static int sd_issue_flush(struct device *dev, sector_t *error_sector)
729{
730 struct scsi_device *sdp = to_scsi_device(dev);
731 struct scsi_disk *sdkp = dev_get_drvdata(dev);
732
733 if (!sdkp)
734 return -ENODEV;
735
736 if (!sdkp->WCE)
737 return 0;
738
739 return sd_sync_cache(sdp);
740}
741
742static void sd_end_flush(request_queue_t *q, struct request *flush_rq)
743{
744 struct request *rq = flush_rq->end_io_data;
745 struct scsi_cmnd *cmd = rq->special;
746 unsigned int bytes = rq->hard_nr_sectors << 9;
747
748 if (!flush_rq->errors) {
749 spin_unlock(q->queue_lock);
750 scsi_io_completion(cmd, bytes, 0);
751 spin_lock(q->queue_lock);
752 } else if (blk_barrier_postflush(rq)) {
753 spin_unlock(q->queue_lock);
754 scsi_io_completion(cmd, 0, bytes);
755 spin_lock(q->queue_lock);
756 } else {
757 /*
758 * force journal abort of barriers
759 */
760 end_that_request_first(rq, -EOPNOTSUPP, rq->hard_nr_sectors);
761 end_that_request_last(rq);
762 }
763}
764
765static int sd_prepare_flush(request_queue_t *q, struct request *rq)
766{
767 struct scsi_device *sdev = q->queuedata;
768 struct scsi_disk *sdkp = dev_get_drvdata(&sdev->sdev_gendev);
769
770 if (sdkp->WCE) {
771 memset(rq->cmd, 0, sizeof(rq->cmd));
772 rq->flags |= REQ_BLOCK_PC | REQ_SOFTBARRIER;
773 rq->timeout = SD_TIMEOUT;
774 rq->cmd[0] = SYNCHRONIZE_CACHE;
775 return 1;
776 }
777
778 return 0;
779}
780
781static void sd_rescan(struct device *dev)
782{
783 struct scsi_disk *sdkp = dev_get_drvdata(dev);
784 sd_revalidate_disk(sdkp->disk);
785}
786
787
788#ifdef CONFIG_COMPAT
789/*
790 * This gets directly called from VFS. When the ioctl
791 * is not recognized we go back to the other translation paths.
792 */
793static long sd_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
794{
795 struct block_device *bdev = file->f_dentry->d_inode->i_bdev;
796 struct gendisk *disk = bdev->bd_disk;
797 struct scsi_device *sdev = scsi_disk(disk)->device;
798
799 /*
800 * If we are in the middle of error recovery, don't let anyone
801 * else try and use this device. Also, if error recovery fails, it
802 * may try and take the device offline, in which case all further
803 * access to the device is prohibited.
804 */
805 if (!scsi_block_when_processing_errors(sdev))
806 return -ENODEV;
807
808 if (sdev->host->hostt->compat_ioctl) {
809 int ret;
810
811 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
812
813 return ret;
814 }
815
816 /*
817 * Let the static ioctl translation table take care of it.
818 */
819 return -ENOIOCTLCMD;
820}
821#endif
822
823static struct block_device_operations sd_fops = {
824 .owner = THIS_MODULE,
825 .open = sd_open,
826 .release = sd_release,
827 .ioctl = sd_ioctl,
828#ifdef CONFIG_COMPAT
829 .compat_ioctl = sd_compat_ioctl,
830#endif
831 .media_changed = sd_media_changed,
832 .revalidate_disk = sd_revalidate_disk,
833};
834
835/**
836 * sd_rw_intr - bottom half handler: called when the lower level
837 * driver has completed (successfully or otherwise) a scsi command.
838 * @SCpnt: mid-level's per command structure.
839 *
840 * Note: potentially run from within an ISR. Must not block.
841 **/
842static void sd_rw_intr(struct scsi_cmnd * SCpnt)
843{
844 int result = SCpnt->result;
845 int this_count = SCpnt->bufflen;
846 int good_bytes = (result == 0 ? this_count : 0);
847 sector_t block_sectors = 1;
848 u64 first_err_block;
849 sector_t error_sector;
850 struct scsi_sense_hdr sshdr;
851 int sense_valid = 0;
852 int sense_deferred = 0;
853 int info_valid;
854
855 if (result) {
856 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
857 if (sense_valid)
858 sense_deferred = scsi_sense_is_deferred(&sshdr);
859 }
860
861#ifdef CONFIG_SCSI_LOGGING
862 SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: %s: res=0x%x\n",
863 SCpnt->request->rq_disk->disk_name, result));
864 if (sense_valid) {
865 SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: sb[respc,sk,asc,"
866 "ascq]=%x,%x,%x,%x\n", sshdr.response_code,
867 sshdr.sense_key, sshdr.asc, sshdr.ascq));
868 }
869#endif
870 /*
871 Handle MEDIUM ERRORs that indicate partial success. Since this is a
872 relatively rare error condition, no care is taken to avoid
873 unnecessary additional work such as memcpy's that could be avoided.
874 */
875
876 /*
877 * If SG_IO from block layer then set good_bytes to stop retries;
878 * else if errors, check them, and if necessary prepare for
879 * (partial) retries.
880 */
881 if (blk_pc_request(SCpnt->request))
882 good_bytes = this_count;
883 else if (driver_byte(result) != 0 &&
884 sense_valid && !sense_deferred) {
885 switch (sshdr.sense_key) {
886 case MEDIUM_ERROR:
887 if (!blk_fs_request(SCpnt->request))
888 break;
889 info_valid = scsi_get_sense_info_fld(
890 SCpnt->sense_buffer, SCSI_SENSE_BUFFERSIZE,
891 &first_err_block);
892 /*
893 * May want to warn and skip if following cast results
894 * in actual truncation (if sector_t < 64 bits)
895 */
896 error_sector = (sector_t)first_err_block;
897 if (SCpnt->request->bio != NULL)
898 block_sectors = bio_sectors(SCpnt->request->bio);
899 switch (SCpnt->device->sector_size) {
900 case 1024:
901 error_sector <<= 1;
902 if (block_sectors < 2)
903 block_sectors = 2;
904 break;
905 case 2048:
906 error_sector <<= 2;
907 if (block_sectors < 4)
908 block_sectors = 4;
909 break;
910 case 4096:
911 error_sector <<=3;
912 if (block_sectors < 8)
913 block_sectors = 8;
914 break;
915 case 256:
916 error_sector >>= 1;
917 break;
918 default:
919 break;
920 }
921
922 error_sector &= ~(block_sectors - 1);
923 good_bytes = (error_sector - SCpnt->request->sector) << 9;
924 if (good_bytes < 0 || good_bytes >= this_count)
925 good_bytes = 0;
926 break;
927
928 case RECOVERED_ERROR: /* an error occurred, but it recovered */
929 case NO_SENSE: /* LLDD got sense data */
930 /*
931 * Inform the user, but make sure that it's not treated
932 * as a hard error.
933 */
934 scsi_print_sense("sd", SCpnt);
935 SCpnt->result = 0;
936 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
937 good_bytes = this_count;
938 break;
939
940 case ILLEGAL_REQUEST:
941 if (SCpnt->device->use_10_for_rw &&
942 (SCpnt->cmnd[0] == READ_10 ||
943 SCpnt->cmnd[0] == WRITE_10))
944 SCpnt->device->use_10_for_rw = 0;
945 if (SCpnt->device->use_10_for_ms &&
946 (SCpnt->cmnd[0] == MODE_SENSE_10 ||
947 SCpnt->cmnd[0] == MODE_SELECT_10))
948 SCpnt->device->use_10_for_ms = 0;
949 break;
950
951 default:
952 break;
953 }
954 }
955 /*
956 * This calls the generic completion function, now that we know
957 * how many actual sectors finished, and how many sectors we need
958 * to say have failed.
959 */
960 scsi_io_completion(SCpnt, good_bytes, block_sectors << 9);
961}
962
963static int media_not_present(struct scsi_disk *sdkp, struct scsi_request *srp)
964{
965 struct scsi_sense_hdr sshdr;
966
967 if (!srp->sr_result)
968 return 0;
969 if (!(driver_byte(srp->sr_result) & DRIVER_SENSE))
970 return 0;
971 /* not invoked for commands that could return deferred errors */
972 if (scsi_request_normalize_sense(srp, &sshdr)) {
973 if (sshdr.sense_key != NOT_READY &&
974 sshdr.sense_key != UNIT_ATTENTION)
975 return 0;
976 if (sshdr.asc != 0x3A) /* medium not present */
977 return 0;
978 }
979 set_media_not_present(sdkp);
980 return 1;
981}
982
983/*
984 * spinup disk - called only in sd_revalidate_disk()
985 */
986static void
987sd_spinup_disk(struct scsi_disk *sdkp, char *diskname,
988 struct scsi_request *SRpnt, unsigned char *buffer) {
989 unsigned char cmd[10];
990 unsigned long spintime_value = 0;
991 int retries, spintime;
992 unsigned int the_result;
993 struct scsi_sense_hdr sshdr;
994 int sense_valid = 0;
995
996 spintime = 0;
997
998 /* Spin up drives, as required. Only do this at boot time */
999 /* Spinup needs to be done for module loads too. */
1000 do {
1001 retries = 0;
1002
1003 do {
1004 cmd[0] = TEST_UNIT_READY;
1005 memset((void *) &cmd[1], 0, 9);
1006
1007 SRpnt->sr_cmd_len = 0;
1008 memset(SRpnt->sr_sense_buffer, 0,
1009 SCSI_SENSE_BUFFERSIZE);
1010 SRpnt->sr_data_direction = DMA_NONE;
1011
1012 scsi_wait_req (SRpnt, (void *) cmd, (void *) buffer,
1013 0/*512*/, SD_TIMEOUT, SD_MAX_RETRIES);
1014
1015 the_result = SRpnt->sr_result;
1016 if (the_result)
1017 sense_valid = scsi_request_normalize_sense(
1018 SRpnt, &sshdr);
1019 retries++;
1020 } while (retries < 3 &&
1021 (!scsi_status_is_good(the_result) ||
1022 ((driver_byte(the_result) & DRIVER_SENSE) &&
1023 sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
1024
1025 /*
1026 * If the drive has indicated to us that it doesn't have
1027 * any media in it, don't bother with any of the rest of
1028 * this crap.
1029 */
1030 if (media_not_present(sdkp, SRpnt))
1031 return;
1032
1033 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
1034 /* no sense, TUR either succeeded or failed
1035 * with a status error */
1036 if(!spintime && !scsi_status_is_good(the_result))
1037 printk(KERN_NOTICE "%s: Unit Not Ready, "
1038 "error = 0x%x\n", diskname, the_result);
1039 break;
1040 }
1041
1042 /*
1043 * The device does not want the automatic start to be issued.
1044 */
1045 if (sdkp->device->no_start_on_add) {
1046 break;
1047 }
1048
1049 /*
1050 * If manual intervention is required, or this is an
1051 * absent USB storage device, a spinup is meaningless.
1052 */
1053 if (sense_valid &&
1054 sshdr.sense_key == NOT_READY &&
1055 sshdr.asc == 4 && sshdr.ascq == 3) {
1056 break; /* manual intervention required */
1057
1058 /*
1059 * Issue command to spin up drive when not ready
1060 */
1061 } else if (sense_valid && sshdr.sense_key == NOT_READY) {
1062 if (!spintime) {
1063 printk(KERN_NOTICE "%s: Spinning up disk...",
1064 diskname);
1065 cmd[0] = START_STOP;
1066 cmd[1] = 1; /* Return immediately */
1067 memset((void *) &cmd[2], 0, 8);
1068 cmd[4] = 1; /* Start spin cycle */
1069 SRpnt->sr_cmd_len = 0;
1070 memset(SRpnt->sr_sense_buffer, 0,
1071 SCSI_SENSE_BUFFERSIZE);
1072
1073 SRpnt->sr_data_direction = DMA_NONE;
1074 scsi_wait_req(SRpnt, (void *)cmd,
1075 (void *) buffer, 0/*512*/,
1076 SD_TIMEOUT, SD_MAX_RETRIES);
1077 spintime_value = jiffies;
1078 }
1079 spintime = 1;
1080 /* Wait 1 second for next try */
1081 msleep(1000);
1082 printk(".");
1083 } else {
1084 /* we don't understand the sense code, so it's
1085 * probably pointless to loop */
1086 if(!spintime) {
1087 printk(KERN_NOTICE "%s: Unit Not Ready, "
1088 "sense:\n", diskname);
1089 scsi_print_req_sense("", SRpnt);
1090 }
1091 break;
1092 }
1093
1094 } while (spintime &&
1095 time_after(spintime_value + 100 * HZ, jiffies));
1096
1097 if (spintime) {
1098 if (scsi_status_is_good(the_result))
1099 printk("ready\n");
1100 else
1101 printk("not responding...\n");
1102 }
1103}
1104
1105/*
1106 * read disk capacity
1107 */
1108static void
1109sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
1110 struct scsi_request *SRpnt, unsigned char *buffer) {
1111 unsigned char cmd[16];
1112 struct scsi_device *sdp = sdkp->device;
1113 int the_result, retries;
1114 int sector_size = 0;
1115 int longrc = 0;
1116 struct scsi_sense_hdr sshdr;
1117 int sense_valid = 0;
1118
1119repeat:
1120 retries = 3;
1121 do {
1122 if (longrc) {
1123 memset((void *) cmd, 0, 16);
1124 cmd[0] = SERVICE_ACTION_IN;
1125 cmd[1] = SAI_READ_CAPACITY_16;
1126 cmd[13] = 12;
1127 memset((void *) buffer, 0, 12);
1128 } else {
1129 cmd[0] = READ_CAPACITY;
1130 memset((void *) &cmd[1], 0, 9);
1131 memset((void *) buffer, 0, 8);
1132 }
1133
1134 SRpnt->sr_cmd_len = 0;
1135 memset(SRpnt->sr_sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1136 SRpnt->sr_data_direction = DMA_FROM_DEVICE;
1137
1138 scsi_wait_req(SRpnt, (void *) cmd, (void *) buffer,
1139 longrc ? 12 : 8, SD_TIMEOUT, SD_MAX_RETRIES);
1140
1141 if (media_not_present(sdkp, SRpnt))
1142 return;
1143
1144 the_result = SRpnt->sr_result;
1145 if (the_result)
1146 sense_valid = scsi_request_normalize_sense(SRpnt,
1147 &sshdr);
1148 retries--;
1149
1150 } while (the_result && retries);
1151
1152 if (the_result && !longrc) {
1153 printk(KERN_NOTICE "%s : READ CAPACITY failed.\n"
1154 "%s : status=%x, message=%02x, host=%d, driver=%02x \n",
1155 diskname, diskname,
1156 status_byte(the_result),
1157 msg_byte(the_result),
1158 host_byte(the_result),
1159 driver_byte(the_result));
1160
1161 if (driver_byte(the_result) & DRIVER_SENSE)
1162 scsi_print_req_sense("sd", SRpnt);
1163 else
1164 printk("%s : sense not available. \n", diskname);
1165
1166 /* Set dirty bit for removable devices if not ready -
1167 * sometimes drives will not report this properly. */
1168 if (sdp->removable &&
1169 sense_valid && sshdr.sense_key == NOT_READY)
1170 sdp->changed = 1;
1171
1172 /* Either no media are present but the drive didn't tell us,
1173 or they are present but the read capacity command fails */
1174 /* sdkp->media_present = 0; -- not always correct */
1175 sdkp->capacity = 0x200000; /* 1 GB - random */
1176
1177 return;
1178 } else if (the_result && longrc) {
1179 /* READ CAPACITY(16) has been failed */
1180 printk(KERN_NOTICE "%s : READ CAPACITY(16) failed.\n"
1181 "%s : status=%x, message=%02x, host=%d, driver=%02x \n",
1182 diskname, diskname,
1183 status_byte(the_result),
1184 msg_byte(the_result),
1185 host_byte(the_result),
1186 driver_byte(the_result));
1187 printk(KERN_NOTICE "%s : use 0xffffffff as device size\n",
1188 diskname);
1189
1190 sdkp->capacity = 1 + (sector_t) 0xffffffff;
1191 goto got_data;
1192 }
1193
1194 if (!longrc) {
1195 sector_size = (buffer[4] << 24) |
1196 (buffer[5] << 16) | (buffer[6] << 8) | buffer[7];
1197 if (buffer[0] == 0xff && buffer[1] == 0xff &&
1198 buffer[2] == 0xff && buffer[3] == 0xff) {
1199 if(sizeof(sdkp->capacity) > 4) {
1200 printk(KERN_NOTICE "%s : very big device. try to use"
1201 " READ CAPACITY(16).\n", diskname);
1202 longrc = 1;
1203 goto repeat;
1204 }
1205 printk(KERN_ERR "%s: too big for this kernel. Use a "
1206 "kernel compiled with support for large block "
1207 "devices.\n", diskname);
1208 sdkp->capacity = 0;
1209 goto got_data;
1210 }
1211 sdkp->capacity = 1 + (((sector_t)buffer[0] << 24) |
1212 (buffer[1] << 16) |
1213 (buffer[2] << 8) |
1214 buffer[3]);
1215 } else {
1216 sdkp->capacity = 1 + (((u64)buffer[0] << 56) |
1217 ((u64)buffer[1] << 48) |
1218 ((u64)buffer[2] << 40) |
1219 ((u64)buffer[3] << 32) |
1220 ((sector_t)buffer[4] << 24) |
1221 ((sector_t)buffer[5] << 16) |
1222 ((sector_t)buffer[6] << 8) |
1223 (sector_t)buffer[7]);
1224
1225 sector_size = (buffer[8] << 24) |
1226 (buffer[9] << 16) | (buffer[10] << 8) | buffer[11];
1227 }
1228
1229 /* Some devices return the total number of sectors, not the
1230 * highest sector number. Make the necessary adjustment. */
1231 if (sdp->fix_capacity)
1232 --sdkp->capacity;
1233
1234got_data:
1235 if (sector_size == 0) {
1236 sector_size = 512;
1237 printk(KERN_NOTICE "%s : sector size 0 reported, "
1238 "assuming 512.\n", diskname);
1239 }
1240
1241 if (sector_size != 512 &&
1242 sector_size != 1024 &&
1243 sector_size != 2048 &&
1244 sector_size != 4096 &&
1245 sector_size != 256) {
1246 printk(KERN_NOTICE "%s : unsupported sector size "
1247 "%d.\n", diskname, sector_size);
1248 /*
1249 * The user might want to re-format the drive with
1250 * a supported sectorsize. Once this happens, it
1251 * would be relatively trivial to set the thing up.
1252 * For this reason, we leave the thing in the table.
1253 */
1254 sdkp->capacity = 0;
1255 /*
1256 * set a bogus sector size so the normal read/write
1257 * logic in the block layer will eventually refuse any
1258 * request on this device without tripping over power
1259 * of two sector size assumptions
1260 */
1261 sector_size = 512;
1262 }
1263 {
1264 /*
1265 * The msdos fs needs to know the hardware sector size
1266 * So I have created this table. See ll_rw_blk.c
1267 * Jacques Gelinas (Jacques@solucorp.qc.ca)
1268 */
1269 int hard_sector = sector_size;
1270 sector_t sz = sdkp->capacity * (hard_sector/256);
1271 request_queue_t *queue = sdp->request_queue;
1272 sector_t mb;
1273
1274 blk_queue_hardsect_size(queue, hard_sector);
1275 /* avoid 64-bit division on 32-bit platforms */
1276 mb = sz >> 1;
1277 sector_div(sz, 1250);
1278 mb -= sz - 974;
1279 sector_div(mb, 1950);
1280
1281 printk(KERN_NOTICE "SCSI device %s: "
1282 "%llu %d-byte hdwr sectors (%llu MB)\n",
1283 diskname, (unsigned long long)sdkp->capacity,
1284 hard_sector, (unsigned long long)mb);
1285 }
1286
1287 /* Rescale capacity to 512-byte units */
1288 if (sector_size == 4096)
1289 sdkp->capacity <<= 3;
1290 else if (sector_size == 2048)
1291 sdkp->capacity <<= 2;
1292 else if (sector_size == 1024)
1293 sdkp->capacity <<= 1;
1294 else if (sector_size == 256)
1295 sdkp->capacity >>= 1;
1296
1297 sdkp->device->sector_size = sector_size;
1298}
1299
1300/* called with buffer of length 512 */
1301static inline int
1302sd_do_mode_sense(struct scsi_request *SRpnt, int dbd, int modepage,
1303 unsigned char *buffer, int len, struct scsi_mode_data *data)
1304{
1305 return __scsi_mode_sense(SRpnt, dbd, modepage, buffer, len,
1306 SD_TIMEOUT, SD_MAX_RETRIES, data);
1307}
1308
1309/*
1310 * read write protect setting, if possible - called only in sd_revalidate_disk()
1311 * called with buffer of length 512
1312 */
1313static void
1314sd_read_write_protect_flag(struct scsi_disk *sdkp, char *diskname,
1315 struct scsi_request *SRpnt, unsigned char *buffer) {
1316 int res;
1317 struct scsi_mode_data data;
1318
1319 set_disk_ro(sdkp->disk, 0);
1320 if (sdkp->device->skip_ms_page_3f) {
1321 printk(KERN_NOTICE "%s: assuming Write Enabled\n", diskname);
1322 return;
1323 }
1324
1325 if (sdkp->device->use_192_bytes_for_3f) {
1326 res = sd_do_mode_sense(SRpnt, 0, 0x3F, buffer, 192, &data);
1327 } else {
1328 /*
1329 * First attempt: ask for all pages (0x3F), but only 4 bytes.
1330 * We have to start carefully: some devices hang if we ask
1331 * for more than is available.
1332 */
1333 res = sd_do_mode_sense(SRpnt, 0, 0x3F, buffer, 4, &data);
1334
1335 /*
1336 * Second attempt: ask for page 0 When only page 0 is
1337 * implemented, a request for page 3F may return Sense Key
1338 * 5: Illegal Request, Sense Code 24: Invalid field in
1339 * CDB.
1340 */
1341 if (!scsi_status_is_good(res))
1342 res = sd_do_mode_sense(SRpnt, 0, 0, buffer, 4, &data);
1343
1344 /*
1345 * Third attempt: ask 255 bytes, as we did earlier.
1346 */
1347 if (!scsi_status_is_good(res))
1348 res = sd_do_mode_sense(SRpnt, 0, 0x3F, buffer, 255,
1349 &data);
1350 }
1351
1352 if (!scsi_status_is_good(res)) {
1353 printk(KERN_WARNING
1354 "%s: test WP failed, assume Write Enabled\n", diskname);
1355 } else {
1356 sdkp->write_prot = ((data.device_specific & 0x80) != 0);
1357 set_disk_ro(sdkp->disk, sdkp->write_prot);
1358 printk(KERN_NOTICE "%s: Write Protect is %s\n", diskname,
1359 sdkp->write_prot ? "on" : "off");
1360 printk(KERN_DEBUG "%s: Mode Sense: %02x %02x %02x %02x\n",
1361 diskname, buffer[0], buffer[1], buffer[2], buffer[3]);
1362 }
1363}
1364
1365/*
1366 * sd_read_cache_type - called only from sd_revalidate_disk()
1367 * called with buffer of length 512
1368 */
1369static void
1370sd_read_cache_type(struct scsi_disk *sdkp, char *diskname,
1371 struct scsi_request *SRpnt, unsigned char *buffer) {
1372 int len = 0, res;
1373
1374 const int dbd = 0; /* DBD */
1375 const int modepage = 0x08; /* current values, cache page */
1376 struct scsi_mode_data data;
1377 struct scsi_sense_hdr sshdr;
1378
1379 if (sdkp->device->skip_ms_page_8)
1380 goto defaults;
1381
1382 /* cautiously ask */
1383 res = sd_do_mode_sense(SRpnt, dbd, modepage, buffer, 4, &data);
1384
1385 if (!scsi_status_is_good(res))
1386 goto bad_sense;
1387
1388 /* that went OK, now ask for the proper length */
1389 len = data.length;
1390
1391 /*
1392 * We're only interested in the first three bytes, actually.
1393 * But the data cache page is defined for the first 20.
1394 */
1395 if (len < 3)
1396 goto bad_sense;
1397 if (len > 20)
1398 len = 20;
1399
1400 /* Take headers and block descriptors into account */
1401 len += data.header_length + data.block_descriptor_length;
1402
1403 /* Get the data */
1404 res = sd_do_mode_sense(SRpnt, dbd, modepage, buffer, len, &data);
1405
1406 if (scsi_status_is_good(res)) {
1407 const char *types[] = {
1408 "write through", "none", "write back",
1409 "write back, no read (daft)"
1410 };
1411 int ct = 0;
1412 int offset = data.header_length +
1413 data.block_descriptor_length + 2;
1414
1415 sdkp->WCE = ((buffer[offset] & 0x04) != 0);
1416 sdkp->RCD = ((buffer[offset] & 0x01) != 0);
1417
1418 ct = sdkp->RCD + 2*sdkp->WCE;
1419
1420 printk(KERN_NOTICE "SCSI device %s: drive cache: %s\n",
1421 diskname, types[ct]);
1422
1423 return;
1424 }
1425
1426bad_sense:
1427 if (scsi_request_normalize_sense(SRpnt, &sshdr) &&
1428 sshdr.sense_key == ILLEGAL_REQUEST &&
1429 sshdr.asc == 0x24 && sshdr.ascq == 0x0)
1430 printk(KERN_NOTICE "%s: cache data unavailable\n",
1431 diskname); /* Invalid field in CDB */
1432 else
1433 printk(KERN_ERR "%s: asking for cache data failed\n",
1434 diskname);
1435
1436defaults:
1437 printk(KERN_ERR "%s: assuming drive cache: write through\n",
1438 diskname);
1439 sdkp->WCE = 0;
1440 sdkp->RCD = 0;
1441}
1442
1443/**
1444 * sd_revalidate_disk - called the first time a new disk is seen,
1445 * performs disk spin up, read_capacity, etc.
1446 * @disk: struct gendisk we care about
1447 **/
1448static int sd_revalidate_disk(struct gendisk *disk)
1449{
1450 struct scsi_disk *sdkp = scsi_disk(disk);
1451 struct scsi_device *sdp = sdkp->device;
1452 struct scsi_request *sreq;
1453 unsigned char *buffer;
1454
1455 SCSI_LOG_HLQUEUE(3, printk("sd_revalidate_disk: disk=%s\n", disk->disk_name));
1456
1457 /*
1458 * If the device is offline, don't try and read capacity or any
1459 * of the other niceties.
1460 */
1461 if (!scsi_device_online(sdp))
1462 goto out;
1463
1464 sreq = scsi_allocate_request(sdp, GFP_KERNEL);
1465 if (!sreq) {
1466 printk(KERN_WARNING "(sd_revalidate_disk:) Request allocation "
1467 "failure.\n");
1468 goto out;
1469 }
1470
1471 buffer = kmalloc(512, GFP_KERNEL | __GFP_DMA);
1472 if (!buffer) {
1473 printk(KERN_WARNING "(sd_revalidate_disk:) Memory allocation "
1474 "failure.\n");
1475 goto out_release_request;
1476 }
1477
1478 /* defaults, until the device tells us otherwise */
1479 sdp->sector_size = 512;
1480 sdkp->capacity = 0;
1481 sdkp->media_present = 1;
1482 sdkp->write_prot = 0;
1483 sdkp->WCE = 0;
1484 sdkp->RCD = 0;
1485
1486 sd_spinup_disk(sdkp, disk->disk_name, sreq, buffer);
1487
1488 /*
1489 * Without media there is no reason to ask; moreover, some devices
1490 * react badly if we do.
1491 */
1492 if (sdkp->media_present) {
1493 sd_read_capacity(sdkp, disk->disk_name, sreq, buffer);
1494 if (sdp->removable)
1495 sd_read_write_protect_flag(sdkp, disk->disk_name,
1496 sreq, buffer);
1497 sd_read_cache_type(sdkp, disk->disk_name, sreq, buffer);
1498 }
1499
1500 set_capacity(disk, sdkp->capacity);
1501 kfree(buffer);
1502
1503 out_release_request:
1504 scsi_release_request(sreq);
1505 out:
1506 return 0;
1507}
1508
1509/**
1510 * sd_probe - called during driver initialization and whenever a
1511 * new scsi device is attached to the system. It is called once
1512 * for each scsi device (not just disks) present.
1513 * @dev: pointer to device object
1514 *
1515 * Returns 0 if successful (or not interested in this scsi device
1516 * (e.g. scanner)); 1 when there is an error.
1517 *
1518 * Note: this function is invoked from the scsi mid-level.
1519 * This function sets up the mapping between a given
1520 * <host,channel,id,lun> (found in sdp) and new device name
1521 * (e.g. /dev/sda). More precisely it is the block device major
1522 * and minor number that is chosen here.
1523 *
1524 * Assume sd_attach is not re-entrant (for time being)
1525 * Also think about sd_attach() and sd_remove() running coincidentally.
1526 **/
1527static int sd_probe(struct device *dev)
1528{
1529 struct scsi_device *sdp = to_scsi_device(dev);
1530 struct scsi_disk *sdkp;
1531 struct gendisk *gd;
1532 u32 index;
1533 int error;
1534
1535 error = -ENODEV;
1536 if ((sdp->type != TYPE_DISK) && (sdp->type != TYPE_MOD))
1537 goto out;
1538
1539 SCSI_LOG_HLQUEUE(3, printk("sd_attach: scsi device: <%d,%d,%d,%d>\n",
1540 sdp->host->host_no, sdp->channel, sdp->id, sdp->lun));
1541
1542 error = -ENOMEM;
1543 sdkp = kmalloc(sizeof(*sdkp), GFP_KERNEL);
1544 if (!sdkp)
1545 goto out;
1546
1547 memset (sdkp, 0, sizeof(*sdkp));
1548 kref_init(&sdkp->kref);
1549
1550 gd = alloc_disk(16);
1551 if (!gd)
1552 goto out_free;
1553
1554 if (!idr_pre_get(&sd_index_idr, GFP_KERNEL))
1555 goto out_put;
1556
1557 spin_lock(&sd_index_lock);
1558 error = idr_get_new(&sd_index_idr, NULL, &index);
1559 spin_unlock(&sd_index_lock);
1560
1561 if (index >= SD_MAX_DISKS)
1562 error = -EBUSY;
1563 if (error)
1564 goto out_put;
1565
1566 sdkp->device = sdp;
1567 sdkp->driver = &sd_template;
1568 sdkp->disk = gd;
1569 sdkp->index = index;
1570 sdkp->openers = 0;
1571
1572 if (!sdp->timeout) {
1573 if (sdp->type == TYPE_DISK)
1574 sdp->timeout = SD_TIMEOUT;
1575 else
1576 sdp->timeout = SD_MOD_TIMEOUT;
1577 }
1578
1579 gd->major = sd_major((index & 0xf0) >> 4);
1580 gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
1581 gd->minors = 16;
1582 gd->fops = &sd_fops;
1583
1584 if (index < 26) {
1585 sprintf(gd->disk_name, "sd%c", 'a' + index % 26);
1586 } else if (index < (26 + 1) * 26) {
1587 sprintf(gd->disk_name, "sd%c%c",
1588 'a' + index / 26 - 1,'a' + index % 26);
1589 } else {
1590 const unsigned int m1 = (index / 26 - 1) / 26 - 1;
1591 const unsigned int m2 = (index / 26 - 1) % 26;
1592 const unsigned int m3 = index % 26;
1593 sprintf(gd->disk_name, "sd%c%c%c",
1594 'a' + m1, 'a' + m2, 'a' + m3);
1595 }
1596
1597 strcpy(gd->devfs_name, sdp->devfs_name);
1598
1599 gd->private_data = &sdkp->driver;
1600
1601 sd_revalidate_disk(gd);
1602
1603 gd->driverfs_dev = &sdp->sdev_gendev;
1604 gd->flags = GENHD_FL_DRIVERFS;
1605 if (sdp->removable)
1606 gd->flags |= GENHD_FL_REMOVABLE;
1607 gd->queue = sdkp->device->request_queue;
1608
1609 dev_set_drvdata(dev, sdkp);
1610 add_disk(gd);
1611
1612 printk(KERN_NOTICE "Attached scsi %sdisk %s at scsi%d, channel %d, "
1613 "id %d, lun %d\n", sdp->removable ? "removable " : "",
1614 gd->disk_name, sdp->host->host_no, sdp->channel,
1615 sdp->id, sdp->lun);
1616
1617 return 0;
1618
1619out_put:
1620 put_disk(gd);
1621out_free:
1622 kfree(sdkp);
1623out:
1624 return error;
1625}
1626
1627/**
1628 * sd_remove - called whenever a scsi disk (previously recognized by
1629 * sd_probe) is detached from the system. It is called (potentially
1630 * multiple times) during sd module unload.
1631 * @sdp: pointer to mid level scsi device object
1632 *
1633 * Note: this function is invoked from the scsi mid-level.
1634 * This function potentially frees up a device name (e.g. /dev/sdc)
1635 * that could be re-used by a subsequent sd_probe().
1636 * This function is not called when the built-in sd driver is "exit-ed".
1637 **/
1638static int sd_remove(struct device *dev)
1639{
1640 struct scsi_disk *sdkp = dev_get_drvdata(dev);
1641
1642 del_gendisk(sdkp->disk);
1643 sd_shutdown(dev);
1644 down(&sd_ref_sem);
1645 kref_put(&sdkp->kref, scsi_disk_release);
1646 up(&sd_ref_sem);
1647
1648 return 0;
1649}
1650
1651/**
1652 * scsi_disk_release - Called to free the scsi_disk structure
1653 * @kref: pointer to embedded kref
1654 *
1655 * sd_ref_sem must be held entering this routine. Because it is
1656 * called on last put, you should always use the scsi_disk_get()
1657 * scsi_disk_put() helpers which manipulate the semaphore directly
1658 * and never do a direct kref_put().
1659 **/
1660static void scsi_disk_release(struct kref *kref)
1661{
1662 struct scsi_disk *sdkp = to_scsi_disk(kref);
1663 struct gendisk *disk = sdkp->disk;
1664
1665 spin_lock(&sd_index_lock);
1666 idr_remove(&sd_index_idr, sdkp->index);
1667 spin_unlock(&sd_index_lock);
1668
1669 disk->private_data = NULL;
1670
1671 put_disk(disk);
1672
1673 kfree(sdkp);
1674}
1675
1676/*
1677 * Send a SYNCHRONIZE CACHE instruction down to the device through
1678 * the normal SCSI command structure. Wait for the command to
1679 * complete.
1680 */
1681static void sd_shutdown(struct device *dev)
1682{
1683 struct scsi_device *sdp = to_scsi_device(dev);
1684 struct scsi_disk *sdkp = dev_get_drvdata(dev);
1685
1686 if (!sdkp)
1687 return; /* this can happen */
1688
1689 if (!sdkp->WCE)
1690 return;
1691
1692 printk(KERN_NOTICE "Synchronizing SCSI cache for disk %s: \n",
1693 sdkp->disk->disk_name);
1694 sd_sync_cache(sdp);
1695}
1696
1697/**
1698 * init_sd - entry point for this driver (both when built in or when
1699 * a module).
1700 *
1701 * Note: this function registers this driver with the scsi mid-level.
1702 **/
1703static int __init init_sd(void)
1704{
1705 int majors = 0, i;
1706
1707 SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
1708
1709 for (i = 0; i < SD_MAJORS; i++)
1710 if (register_blkdev(sd_major(i), "sd") == 0)
1711 majors++;
1712
1713 if (!majors)
1714 return -ENODEV;
1715
1716 return scsi_register_driver(&sd_template.gendrv);
1717}
1718
1719/**
1720 * exit_sd - exit point for this driver (when it is a module).
1721 *
1722 * Note: this function unregisters this driver from the scsi mid-level.
1723 **/
1724static void __exit exit_sd(void)
1725{
1726 int i;
1727
1728 SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
1729
1730 scsi_unregister_driver(&sd_template.gendrv);
1731 for (i = 0; i < SD_MAJORS; i++)
1732 unregister_blkdev(sd_major(i), "sd");
1733}
1734
1735MODULE_LICENSE("GPL");
1736MODULE_AUTHOR("Eric Youngdale");
1737MODULE_DESCRIPTION("SCSI disk (sd) driver");
1738
1739module_init(init_sd);
1740module_exit(exit_sd);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-01 13:33:43 -0400