a7942e5c8be8c91dfc3f5dd45ee96fa4195be987
[linux-2.6.git] / drivers / scsi / sd.c
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/module.h>
36 #include <linux/fs.h>
37 #include <linux/kernel.h>
38 #include <linux/mm.h>
39 #include <linux/bio.h>
40 #include <linux/genhd.h>
41 #include <linux/hdreg.h>
42 #include <linux/errno.h>
43 #include <linux/idr.h>
44 #include <linux/interrupt.h>
45 #include <linux/init.h>
46 #include <linux/blkdev.h>
47 #include <linux/blkpg.h>
48 #include <linux/delay.h>
49 #include <linux/mutex.h>
50 #include <linux/string_helpers.h>
51 #include <linux/async.h>
52 #include <linux/slab.h>
53 #include <asm/uaccess.h>
54 #include <asm/unaligned.h>
55
56 #include <scsi/scsi.h>
57 #include <scsi/scsi_cmnd.h>
58 #include <scsi/scsi_dbg.h>
59 #include <scsi/scsi_device.h>
60 #include <scsi/scsi_driver.h>
61 #include <scsi/scsi_eh.h>
62 #include <scsi/scsi_host.h>
63 #include <scsi/scsi_ioctl.h>
64 #include <scsi/scsicam.h>
65
66 #include "sd.h"
67 #include "scsi_logging.h"
68
69 MODULE_AUTHOR("Eric Youngdale");
70 MODULE_DESCRIPTION("SCSI disk (sd) driver");
71 MODULE_LICENSE("GPL");
72
73 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
74 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
75 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
76 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
77 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
78 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
79 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
80 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
81 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
82 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
83 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
84 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
85 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
86 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
87 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
88 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
89 MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
90 MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
91 MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
92
93 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
94 #define SD_MINORS       16
95 #else
96 #define SD_MINORS       0
97 #endif
98
99 static void sd_config_discard(struct scsi_disk *, unsigned int);
100 static int  sd_revalidate_disk(struct gendisk *);
101 static void sd_unlock_native_capacity(struct gendisk *disk);
102 static int  sd_probe(struct device *);
103 static int  sd_remove(struct device *);
104 static void sd_shutdown(struct device *);
105 static int sd_suspend(struct device *, pm_message_t state);
106 static int sd_resume(struct device *);
107 static void sd_rescan(struct device *);
108 static int sd_done(struct scsi_cmnd *);
109 static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
110 static void scsi_disk_release(struct device *cdev);
111 static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);
112 static void sd_print_result(struct scsi_disk *, int);
113
114 static DEFINE_SPINLOCK(sd_index_lock);
115 static DEFINE_IDA(sd_index_ida);
116
117 /* This semaphore is used to mediate the 0->1 reference get in the
118  * face of object destruction (i.e. we can't allow a get on an
119  * object after last put) */
120 static DEFINE_MUTEX(sd_ref_mutex);
121
122 static struct kmem_cache *sd_cdb_cache;
123 static mempool_t *sd_cdb_pool;
124
125 static const char *sd_cache_types[] = {
126         "write through", "none", "write back",
127         "write back, no read (daft)"
128 };
129
130 static ssize_t
131 sd_store_cache_type(struct device *dev, struct device_attribute *attr,
132                     const char *buf, size_t count)
133 {
134         int i, ct = -1, rcd, wce, sp;
135         struct scsi_disk *sdkp = to_scsi_disk(dev);
136         struct scsi_device *sdp = sdkp->device;
137         char buffer[64];
138         char *buffer_data;
139         struct scsi_mode_data data;
140         struct scsi_sense_hdr sshdr;
141         int len;
142
143         if (sdp->type != TYPE_DISK)
144                 /* no cache control on RBC devices; theoretically they
145                  * can do it, but there's probably so many exceptions
146                  * it's not worth the risk */
147                 return -EINVAL;
148
149         for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
150                 len = strlen(sd_cache_types[i]);
151                 if (strncmp(sd_cache_types[i], buf, len) == 0 &&
152                     buf[len] == '\n') {
153                         ct = i;
154                         break;
155                 }
156         }
157         if (ct < 0)
158                 return -EINVAL;
159         rcd = ct & 0x01 ? 1 : 0;
160         wce = ct & 0x02 ? 1 : 0;
161         if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
162                             SD_MAX_RETRIES, &data, NULL))
163                 return -EINVAL;
164         len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
165                   data.block_descriptor_length);
166         buffer_data = buffer + data.header_length +
167                 data.block_descriptor_length;
168         buffer_data[2] &= ~0x05;
169         buffer_data[2] |= wce << 2 | rcd;
170         sp = buffer_data[0] & 0x80 ? 1 : 0;
171
172         if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
173                              SD_MAX_RETRIES, &data, &sshdr)) {
174                 if (scsi_sense_valid(&sshdr))
175                         sd_print_sense_hdr(sdkp, &sshdr);
176                 return -EINVAL;
177         }
178         revalidate_disk(sdkp->disk);
179         return count;
180 }
181
182 static ssize_t
183 sd_store_manage_start_stop(struct device *dev, struct device_attribute *attr,
184                            const char *buf, size_t count)
185 {
186         struct scsi_disk *sdkp = to_scsi_disk(dev);
187         struct scsi_device *sdp = sdkp->device;
188
189         if (!capable(CAP_SYS_ADMIN))
190                 return -EACCES;
191
192         sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);
193
194         return count;
195 }
196
197 static ssize_t
198 sd_store_allow_restart(struct device *dev, struct device_attribute *attr,
199                        const char *buf, size_t count)
200 {
201         struct scsi_disk *sdkp = to_scsi_disk(dev);
202         struct scsi_device *sdp = sdkp->device;
203
204         if (!capable(CAP_SYS_ADMIN))
205                 return -EACCES;
206
207         if (sdp->type != TYPE_DISK)
208                 return -EINVAL;
209
210         sdp->allow_restart = simple_strtoul(buf, NULL, 10);
211
212         return count;
213 }
214
215 static ssize_t
216 sd_show_cache_type(struct device *dev, struct device_attribute *attr,
217                    char *buf)
218 {
219         struct scsi_disk *sdkp = to_scsi_disk(dev);
220         int ct = sdkp->RCD + 2*sdkp->WCE;
221
222         return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
223 }
224
225 static ssize_t
226 sd_show_fua(struct device *dev, struct device_attribute *attr, char *buf)
227 {
228         struct scsi_disk *sdkp = to_scsi_disk(dev);
229
230         return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
231 }
232
233 static ssize_t
234 sd_show_manage_start_stop(struct device *dev, struct device_attribute *attr,
235                           char *buf)
236 {
237         struct scsi_disk *sdkp = to_scsi_disk(dev);
238         struct scsi_device *sdp = sdkp->device;
239
240         return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
241 }
242
243 static ssize_t
244 sd_show_allow_restart(struct device *dev, struct device_attribute *attr,
245                       char *buf)
246 {
247         struct scsi_disk *sdkp = to_scsi_disk(dev);
248
249         return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
250 }
251
252 static ssize_t
253 sd_show_protection_type(struct device *dev, struct device_attribute *attr,
254                         char *buf)
255 {
256         struct scsi_disk *sdkp = to_scsi_disk(dev);
257
258         return snprintf(buf, 20, "%u\n", sdkp->protection_type);
259 }
260
261 static ssize_t
262 sd_show_protection_mode(struct device *dev, struct device_attribute *attr,
263                         char *buf)
264 {
265         struct scsi_disk *sdkp = to_scsi_disk(dev);
266         struct scsi_device *sdp = sdkp->device;
267         unsigned int dif, dix;
268
269         dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
270         dix = scsi_host_dix_capable(sdp->host, sdkp->protection_type);
271
272         if (!dix && scsi_host_dix_capable(sdp->host, SD_DIF_TYPE0_PROTECTION)) {
273                 dif = 0;
274                 dix = 1;
275         }
276
277         if (!dif && !dix)
278                 return snprintf(buf, 20, "none\n");
279
280         return snprintf(buf, 20, "%s%u\n", dix ? "dix" : "dif", dif);
281 }
282
283 static ssize_t
284 sd_show_app_tag_own(struct device *dev, struct device_attribute *attr,
285                     char *buf)
286 {
287         struct scsi_disk *sdkp = to_scsi_disk(dev);
288
289         return snprintf(buf, 20, "%u\n", sdkp->ATO);
290 }
291
292 static ssize_t
293 sd_show_thin_provisioning(struct device *dev, struct device_attribute *attr,
294                           char *buf)
295 {
296         struct scsi_disk *sdkp = to_scsi_disk(dev);
297
298         return snprintf(buf, 20, "%u\n", sdkp->lbpme);
299 }
300
301 static const char *lbp_mode[] = {
302         [SD_LBP_FULL]           = "full",
303         [SD_LBP_UNMAP]          = "unmap",
304         [SD_LBP_WS16]           = "writesame_16",
305         [SD_LBP_WS10]           = "writesame_10",
306         [SD_LBP_ZERO]           = "writesame_zero",
307         [SD_LBP_DISABLE]        = "disabled",
308 };
309
310 static ssize_t
311 sd_show_provisioning_mode(struct device *dev, struct device_attribute *attr,
312                           char *buf)
313 {
314         struct scsi_disk *sdkp = to_scsi_disk(dev);
315
316         return snprintf(buf, 20, "%s\n", lbp_mode[sdkp->provisioning_mode]);
317 }
318
319 static ssize_t
320 sd_store_provisioning_mode(struct device *dev, struct device_attribute *attr,
321                            const char *buf, size_t count)
322 {
323         struct scsi_disk *sdkp = to_scsi_disk(dev);
324         struct scsi_device *sdp = sdkp->device;
325
326         if (!capable(CAP_SYS_ADMIN))
327                 return -EACCES;
328
329         if (sdp->type != TYPE_DISK)
330                 return -EINVAL;
331
332         if (!strncmp(buf, lbp_mode[SD_LBP_UNMAP], 20))
333                 sd_config_discard(sdkp, SD_LBP_UNMAP);
334         else if (!strncmp(buf, lbp_mode[SD_LBP_WS16], 20))
335                 sd_config_discard(sdkp, SD_LBP_WS16);
336         else if (!strncmp(buf, lbp_mode[SD_LBP_WS10], 20))
337                 sd_config_discard(sdkp, SD_LBP_WS10);
338         else if (!strncmp(buf, lbp_mode[SD_LBP_ZERO], 20))
339                 sd_config_discard(sdkp, SD_LBP_ZERO);
340         else if (!strncmp(buf, lbp_mode[SD_LBP_DISABLE], 20))
341                 sd_config_discard(sdkp, SD_LBP_DISABLE);
342         else
343                 return -EINVAL;
344
345         return count;
346 }
347
348 static struct device_attribute sd_disk_attrs[] = {
349         __ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
350                sd_store_cache_type),
351         __ATTR(FUA, S_IRUGO, sd_show_fua, NULL),
352         __ATTR(allow_restart, S_IRUGO|S_IWUSR, sd_show_allow_restart,
353                sd_store_allow_restart),
354         __ATTR(manage_start_stop, S_IRUGO|S_IWUSR, sd_show_manage_start_stop,
355                sd_store_manage_start_stop),
356         __ATTR(protection_type, S_IRUGO, sd_show_protection_type, NULL),
357         __ATTR(protection_mode, S_IRUGO, sd_show_protection_mode, NULL),
358         __ATTR(app_tag_own, S_IRUGO, sd_show_app_tag_own, NULL),
359         __ATTR(thin_provisioning, S_IRUGO, sd_show_thin_provisioning, NULL),
360         __ATTR(provisioning_mode, S_IRUGO|S_IWUSR, sd_show_provisioning_mode,
361                sd_store_provisioning_mode),
362         __ATTR_NULL,
363 };
364
365 static struct class sd_disk_class = {
366         .name           = "scsi_disk",
367         .owner          = THIS_MODULE,
368         .dev_release    = scsi_disk_release,
369         .dev_attrs      = sd_disk_attrs,
370 };
371
372 static struct scsi_driver sd_template = {
373         .owner                  = THIS_MODULE,
374         .gendrv = {
375                 .name           = "sd",
376                 .probe          = sd_probe,
377                 .remove         = sd_remove,
378                 .suspend        = sd_suspend,
379                 .resume         = sd_resume,
380                 .shutdown       = sd_shutdown,
381         },
382         .rescan                 = sd_rescan,
383         .done                   = sd_done,
384 };
385
386 /*
387  * Device no to disk mapping:
388  * 
389  *       major         disc2     disc  p1
390  *   |............|.............|....|....| <- dev_t
391  *    31        20 19          8 7  4 3  0
392  * 
393  * Inside a major, we have 16k disks, however mapped non-
394  * contiguously. The first 16 disks are for major0, the next
395  * ones with major1, ... Disk 256 is for major0 again, disk 272 
396  * for major1, ... 
397  * As we stay compatible with our numbering scheme, we can reuse 
398  * the well-know SCSI majors 8, 65--71, 136--143.
399  */
400 static int sd_major(int major_idx)
401 {
402         switch (major_idx) {
403         case 0:
404                 return SCSI_DISK0_MAJOR;
405         case 1 ... 7:
406                 return SCSI_DISK1_MAJOR + major_idx - 1;
407         case 8 ... 15:
408                 return SCSI_DISK8_MAJOR + major_idx - 8;
409         default:
410                 BUG();
411                 return 0;       /* shut up gcc */
412         }
413 }
414
415 static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
416 {
417         struct scsi_disk *sdkp = NULL;
418
419         if (disk->private_data) {
420                 sdkp = scsi_disk(disk);
421                 if (scsi_device_get(sdkp->device) == 0)
422                         get_device(&sdkp->dev);
423                 else
424                         sdkp = NULL;
425         }
426         return sdkp;
427 }
428
429 static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
430 {
431         struct scsi_disk *sdkp;
432
433         mutex_lock(&sd_ref_mutex);
434         sdkp = __scsi_disk_get(disk);
435         mutex_unlock(&sd_ref_mutex);
436         return sdkp;
437 }
438
439 static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev)
440 {
441         struct scsi_disk *sdkp;
442
443         mutex_lock(&sd_ref_mutex);
444         sdkp = dev_get_drvdata(dev);
445         if (sdkp)
446                 sdkp = __scsi_disk_get(sdkp->disk);
447         mutex_unlock(&sd_ref_mutex);
448         return sdkp;
449 }
450
451 static void scsi_disk_put(struct scsi_disk *sdkp)
452 {
453         struct scsi_device *sdev = sdkp->device;
454
455         mutex_lock(&sd_ref_mutex);
456         put_device(&sdkp->dev);
457         scsi_device_put(sdev);
458         mutex_unlock(&sd_ref_mutex);
459 }
460
461 static void sd_prot_op(struct scsi_cmnd *scmd, unsigned int dif)
462 {
463         unsigned int prot_op = SCSI_PROT_NORMAL;
464         unsigned int dix = scsi_prot_sg_count(scmd);
465
466         if (scmd->sc_data_direction == DMA_FROM_DEVICE) {
467                 if (dif && dix)
468                         prot_op = SCSI_PROT_READ_PASS;
469                 else if (dif && !dix)
470                         prot_op = SCSI_PROT_READ_STRIP;
471                 else if (!dif && dix)
472                         prot_op = SCSI_PROT_READ_INSERT;
473         } else {
474                 if (dif && dix)
475                         prot_op = SCSI_PROT_WRITE_PASS;
476                 else if (dif && !dix)
477                         prot_op = SCSI_PROT_WRITE_INSERT;
478                 else if (!dif && dix)
479                         prot_op = SCSI_PROT_WRITE_STRIP;
480         }
481
482         scsi_set_prot_op(scmd, prot_op);
483         scsi_set_prot_type(scmd, dif);
484 }
485
486 static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
487 {
488         struct request_queue *q = sdkp->disk->queue;
489         unsigned int logical_block_size = sdkp->device->sector_size;
490         unsigned int max_blocks = 0;
491
492         q->limits.discard_zeroes_data = sdkp->lbprz;
493         q->limits.discard_alignment = sdkp->unmap_alignment *
494                 logical_block_size;
495         q->limits.discard_granularity =
496                 max(sdkp->physical_block_size,
497                     sdkp->unmap_granularity * logical_block_size);
498
499         switch (mode) {
500
501         case SD_LBP_DISABLE:
502                 q->limits.max_discard_sectors = 0;
503                 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
504                 return;
505
506         case SD_LBP_UNMAP:
507                 max_blocks = min_not_zero(sdkp->max_unmap_blocks, 0xffffffff);
508                 break;
509
510         case SD_LBP_WS16:
511                 max_blocks = min_not_zero(sdkp->max_ws_blocks, 0xffffffff);
512                 break;
513
514         case SD_LBP_WS10:
515                 max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
516                 break;
517
518         case SD_LBP_ZERO:
519                 max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
520                 q->limits.discard_zeroes_data = 1;
521                 break;
522         }
523
524         q->limits.max_discard_sectors = max_blocks * (logical_block_size >> 9);
525         queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
526
527         sdkp->provisioning_mode = mode;
528 }
529
530 /**
531  * scsi_setup_discard_cmnd - unmap blocks on thinly provisioned device
532  * @sdp: scsi device to operate one
533  * @rq: Request to prepare
534  *
535  * Will issue either UNMAP or WRITE SAME(16) depending on preference
536  * indicated by target device.
537  **/
538 static int scsi_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
539 {
540         struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
541         struct bio *bio = rq->bio;
542         sector_t sector = bio->bi_sector;
543         unsigned int nr_sectors = bio_sectors(bio);
544         unsigned int len;
545         int ret;
546         char *buf;
547         struct page *page;
548
549         if (sdkp->device->sector_size == 4096) {
550                 sector >>= 3;
551                 nr_sectors >>= 3;
552         }
553
554         rq->timeout = SD_TIMEOUT;
555
556         memset(rq->cmd, 0, rq->cmd_len);
557
558         page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
559         if (!page)
560                 return BLKPREP_DEFER;
561
562         switch (sdkp->provisioning_mode) {
563         case SD_LBP_UNMAP:
564                 buf = page_address(page);
565
566                 rq->cmd_len = 10;
567                 rq->cmd[0] = UNMAP;
568                 rq->cmd[8] = 24;
569
570                 put_unaligned_be16(6 + 16, &buf[0]);
571                 put_unaligned_be16(16, &buf[2]);
572                 put_unaligned_be64(sector, &buf[8]);
573                 put_unaligned_be32(nr_sectors, &buf[16]);
574
575                 len = 24;
576                 break;
577
578         case SD_LBP_WS16:
579                 rq->cmd_len = 16;
580                 rq->cmd[0] = WRITE_SAME_16;
581                 rq->cmd[1] = 0x8; /* UNMAP */
582                 put_unaligned_be64(sector, &rq->cmd[2]);
583                 put_unaligned_be32(nr_sectors, &rq->cmd[10]);
584
585                 len = sdkp->device->sector_size;
586                 break;
587
588         case SD_LBP_WS10:
589         case SD_LBP_ZERO:
590                 rq->cmd_len = 10;
591                 rq->cmd[0] = WRITE_SAME;
592                 if (sdkp->provisioning_mode == SD_LBP_WS10)
593                         rq->cmd[1] = 0x8; /* UNMAP */
594                 put_unaligned_be32(sector, &rq->cmd[2]);
595                 put_unaligned_be16(nr_sectors, &rq->cmd[7]);
596
597                 len = sdkp->device->sector_size;
598                 break;
599
600         default:
601                 ret = BLKPREP_KILL;
602                 goto out;
603         }
604
605         blk_add_request_payload(rq, page, len);
606         ret = scsi_setup_blk_pc_cmnd(sdp, rq);
607         rq->buffer = page_address(page);
608
609 out:
610         if (ret != BLKPREP_OK) {
611                 __free_page(page);
612                 rq->buffer = NULL;
613         }
614         return ret;
615 }
616
617 static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq)
618 {
619         rq->timeout = SD_FLUSH_TIMEOUT;
620         rq->retries = SD_MAX_RETRIES;
621         rq->cmd[0] = SYNCHRONIZE_CACHE;
622         rq->cmd_len = 10;
623
624         return scsi_setup_blk_pc_cmnd(sdp, rq);
625 }
626
627 static void sd_unprep_fn(struct request_queue *q, struct request *rq)
628 {
629         if (rq->cmd_flags & REQ_DISCARD) {
630                 free_page((unsigned long)rq->buffer);
631                 rq->buffer = NULL;
632         }
633 }
634
635 /**
636  *      sd_init_command - build a scsi (read or write) command from
637  *      information in the request structure.
638  *      @SCpnt: pointer to mid-level's per scsi command structure that
639  *      contains request and into which the scsi command is written
640  *
641  *      Returns 1 if successful and 0 if error (or cannot be done now).
642  **/
643 static int sd_prep_fn(struct request_queue *q, struct request *rq)
644 {
645         struct scsi_cmnd *SCpnt;
646         struct scsi_device *sdp = q->queuedata;
647         struct gendisk *disk = rq->rq_disk;
648         struct scsi_disk *sdkp;
649         sector_t block = blk_rq_pos(rq);
650         sector_t threshold;
651         unsigned int this_count = blk_rq_sectors(rq);
652         int ret, host_dif;
653         unsigned char protect;
654
655         /*
656          * Discard request come in as REQ_TYPE_FS but we turn them into
657          * block PC requests to make life easier.
658          */
659         if (rq->cmd_flags & REQ_DISCARD) {
660                 ret = scsi_setup_discard_cmnd(sdp, rq);
661                 goto out;
662         } else if (rq->cmd_flags & REQ_FLUSH) {
663                 ret = scsi_setup_flush_cmnd(sdp, rq);
664                 goto out;
665         } else if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
666                 ret = scsi_setup_blk_pc_cmnd(sdp, rq);
667                 goto out;
668         } else if (rq->cmd_type != REQ_TYPE_FS) {
669                 ret = BLKPREP_KILL;
670                 goto out;
671         }
672         ret = scsi_setup_fs_cmnd(sdp, rq);
673         if (ret != BLKPREP_OK)
674                 goto out;
675         SCpnt = rq->special;
676         sdkp = scsi_disk(disk);
677
678         /* from here on until we're complete, any goto out
679          * is used for a killable error condition */
680         ret = BLKPREP_KILL;
681
682         SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
683                                         "sd_init_command: block=%llu, "
684                                         "count=%d\n",
685                                         (unsigned long long)block,
686                                         this_count));
687
688         if (!sdp || !scsi_device_online(sdp) ||
689             block + blk_rq_sectors(rq) > get_capacity(disk)) {
690                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
691                                                 "Finishing %u sectors\n",
692                                                 blk_rq_sectors(rq)));
693                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
694                                                 "Retry with 0x%p\n", SCpnt));
695                 goto out;
696         }
697
698         if (sdp->changed) {
699                 /*
700                  * quietly refuse to do anything to a changed disc until 
701                  * the changed bit has been reset
702                  */
703                 /* printk("SCSI disk has been changed or is not present. Prohibiting further I/O.\n"); */
704                 goto out;
705         }
706
707         /*
708          * Some SD card readers can't handle multi-sector accesses which touch
709          * the last one or two hardware sectors.  Split accesses as needed.
710          */
711         threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
712                 (sdp->sector_size / 512);
713
714         if (unlikely(sdp->last_sector_bug && block + this_count > threshold)) {
715                 if (block < threshold) {
716                         /* Access up to the threshold but not beyond */
717                         this_count = threshold - block;
718                 } else {
719                         /* Access only a single hardware sector */
720                         this_count = sdp->sector_size / 512;
721                 }
722         }
723
724         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
725                                         (unsigned long long)block));
726
727         /*
728          * If we have a 1K hardware sectorsize, prevent access to single
729          * 512 byte sectors.  In theory we could handle this - in fact
730          * the scsi cdrom driver must be able to handle this because
731          * we typically use 1K blocksizes, and cdroms typically have
732          * 2K hardware sectorsizes.  Of course, things are simpler
733          * with the cdrom, since it is read-only.  For performance
734          * reasons, the filesystems should be able to handle this
735          * and not force the scsi disk driver to use bounce buffers
736          * for this.
737          */
738         if (sdp->sector_size == 1024) {
739                 if ((block & 1) || (blk_rq_sectors(rq) & 1)) {
740                         scmd_printk(KERN_ERR, SCpnt,
741                                     "Bad block number requested\n");
742                         goto out;
743                 } else {
744                         block = block >> 1;
745                         this_count = this_count >> 1;
746                 }
747         }
748         if (sdp->sector_size == 2048) {
749                 if ((block & 3) || (blk_rq_sectors(rq) & 3)) {
750                         scmd_printk(KERN_ERR, SCpnt,
751                                     "Bad block number requested\n");
752                         goto out;
753                 } else {
754                         block = block >> 2;
755                         this_count = this_count >> 2;
756                 }
757         }
758         if (sdp->sector_size == 4096) {
759                 if ((block & 7) || (blk_rq_sectors(rq) & 7)) {
760                         scmd_printk(KERN_ERR, SCpnt,
761                                     "Bad block number requested\n");
762                         goto out;
763                 } else {
764                         block = block >> 3;
765                         this_count = this_count >> 3;
766                 }
767         }
768         if (rq_data_dir(rq) == WRITE) {
769                 if (!sdp->writeable) {
770                         goto out;
771                 }
772                 SCpnt->cmnd[0] = WRITE_6;
773                 SCpnt->sc_data_direction = DMA_TO_DEVICE;
774
775                 if (blk_integrity_rq(rq) &&
776                     sd_dif_prepare(rq, block, sdp->sector_size) == -EIO)
777                         goto out;
778
779         } else if (rq_data_dir(rq) == READ) {
780                 SCpnt->cmnd[0] = READ_6;
781                 SCpnt->sc_data_direction = DMA_FROM_DEVICE;
782         } else {
783                 scmd_printk(KERN_ERR, SCpnt, "Unknown command %x\n", rq->cmd_flags);
784                 goto out;
785         }
786
787         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
788                                         "%s %d/%u 512 byte blocks.\n",
789                                         (rq_data_dir(rq) == WRITE) ?
790                                         "writing" : "reading", this_count,
791                                         blk_rq_sectors(rq)));
792
793         /* Set RDPROTECT/WRPROTECT if disk is formatted with DIF */
794         host_dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
795         if (host_dif)
796                 protect = 1 << 5;
797         else
798                 protect = 0;
799
800         if (host_dif == SD_DIF_TYPE2_PROTECTION) {
801                 SCpnt->cmnd = mempool_alloc(sd_cdb_pool, GFP_ATOMIC);
802
803                 if (unlikely(SCpnt->cmnd == NULL)) {
804                         ret = BLKPREP_DEFER;
805                         goto out;
806                 }
807
808                 SCpnt->cmd_len = SD_EXT_CDB_SIZE;
809                 memset(SCpnt->cmnd, 0, SCpnt->cmd_len);
810                 SCpnt->cmnd[0] = VARIABLE_LENGTH_CMD;
811                 SCpnt->cmnd[7] = 0x18;
812                 SCpnt->cmnd[9] = (rq_data_dir(rq) == READ) ? READ_32 : WRITE_32;
813                 SCpnt->cmnd[10] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
814
815                 /* LBA */
816                 SCpnt->cmnd[12] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
817                 SCpnt->cmnd[13] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
818                 SCpnt->cmnd[14] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
819                 SCpnt->cmnd[15] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
820                 SCpnt->cmnd[16] = (unsigned char) (block >> 24) & 0xff;
821                 SCpnt->cmnd[17] = (unsigned char) (block >> 16) & 0xff;
822                 SCpnt->cmnd[18] = (unsigned char) (block >> 8) & 0xff;
823                 SCpnt->cmnd[19] = (unsigned char) block & 0xff;
824
825                 /* Expected Indirect LBA */
826                 SCpnt->cmnd[20] = (unsigned char) (block >> 24) & 0xff;
827                 SCpnt->cmnd[21] = (unsigned char) (block >> 16) & 0xff;
828                 SCpnt->cmnd[22] = (unsigned char) (block >> 8) & 0xff;
829                 SCpnt->cmnd[23] = (unsigned char) block & 0xff;
830
831                 /* Transfer length */
832                 SCpnt->cmnd[28] = (unsigned char) (this_count >> 24) & 0xff;
833                 SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
834                 SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
835                 SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
836         } else if (block > 0xffffffff) {
837                 SCpnt->cmnd[0] += READ_16 - READ_6;
838                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
839                 SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
840                 SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
841                 SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
842                 SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
843                 SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
844                 SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
845                 SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
846                 SCpnt->cmnd[9] = (unsigned char) block & 0xff;
847                 SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
848                 SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
849                 SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
850                 SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
851                 SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
852         } else if ((this_count > 0xff) || (block > 0x1fffff) ||
853                    scsi_device_protection(SCpnt->device) ||
854                    SCpnt->device->use_10_for_rw) {
855                 if (this_count > 0xffff)
856                         this_count = 0xffff;
857
858                 SCpnt->cmnd[0] += READ_10 - READ_6;
859                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
860                 SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
861                 SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
862                 SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
863                 SCpnt->cmnd[5] = (unsigned char) block & 0xff;
864                 SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
865                 SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
866                 SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
867         } else {
868                 if (unlikely(rq->cmd_flags & REQ_FUA)) {
869                         /*
870                          * This happens only if this drive failed
871                          * 10byte rw command with ILLEGAL_REQUEST
872                          * during operation and thus turned off
873                          * use_10_for_rw.
874                          */
875                         scmd_printk(KERN_ERR, SCpnt,
876                                     "FUA write on READ/WRITE(6) drive\n");
877                         goto out;
878                 }
879
880                 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
881                 SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
882                 SCpnt->cmnd[3] = (unsigned char) block & 0xff;
883                 SCpnt->cmnd[4] = (unsigned char) this_count;
884                 SCpnt->cmnd[5] = 0;
885         }
886         SCpnt->sdb.length = this_count * sdp->sector_size;
887
888         /* If DIF or DIX is enabled, tell HBA how to handle request */
889         if (host_dif || scsi_prot_sg_count(SCpnt))
890                 sd_prot_op(SCpnt, host_dif);
891
892         /*
893          * We shouldn't disconnect in the middle of a sector, so with a dumb
894          * host adapter, it's safe to assume that we can at least transfer
895          * this many bytes between each connect / disconnect.
896          */
897         SCpnt->transfersize = sdp->sector_size;
898         SCpnt->underflow = this_count << 9;
899         SCpnt->allowed = SD_MAX_RETRIES;
900
901         /*
902          * This indicates that the command is ready from our end to be
903          * queued.
904          */
905         ret = BLKPREP_OK;
906  out:
907         return scsi_prep_return(q, rq, ret);
908 }
909
910 /**
911  *      sd_open - open a scsi disk device
912  *      @inode: only i_rdev member may be used
913  *      @filp: only f_mode and f_flags may be used
914  *
915  *      Returns 0 if successful. Returns a negated errno value in case 
916  *      of error.
917  *
918  *      Note: This can be called from a user context (e.g. fsck(1) )
919  *      or from within the kernel (e.g. as a result of a mount(1) ).
920  *      In the latter case @inode and @filp carry an abridged amount
921  *      of information as noted above.
922  *
923  *      Locking: called with bdev->bd_mutex held.
924  **/
925 static int sd_open(struct block_device *bdev, fmode_t mode)
926 {
927         struct scsi_disk *sdkp = scsi_disk_get(bdev->bd_disk);
928         struct scsi_device *sdev;
929         int retval;
930
931         if (!sdkp)
932                 return -ENXIO;
933
934         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
935
936         sdev = sdkp->device;
937
938         retval = scsi_autopm_get_device(sdev);
939         if (retval)
940                 goto error_autopm;
941
942         /*
943          * If the device is in error recovery, wait until it is done.
944          * If the device is offline, then disallow any access to it.
945          */
946         retval = -ENXIO;
947         if (!scsi_block_when_processing_errors(sdev))
948                 goto error_out;
949
950         if (sdev->removable || sdkp->write_prot)
951                 check_disk_change(bdev);
952
953         /*
954          * If the drive is empty, just let the open fail.
955          */
956         retval = -ENOMEDIUM;
957         if (sdev->removable && !sdkp->media_present && !(mode & FMODE_NDELAY))
958                 goto error_out;
959
960         /*
961          * If the device has the write protect tab set, have the open fail
962          * if the user expects to be able to write to the thing.
963          */
964         retval = -EROFS;
965         if (sdkp->write_prot && (mode & FMODE_WRITE))
966                 goto error_out;
967
968         /*
969          * It is possible that the disk changing stuff resulted in
970          * the device being taken offline.  If this is the case,
971          * report this to the user, and don't pretend that the
972          * open actually succeeded.
973          */
974         retval = -ENXIO;
975         if (!scsi_device_online(sdev))
976                 goto error_out;
977
978         if ((atomic_inc_return(&sdkp->openers) == 1) && sdev->removable) {
979                 if (scsi_block_when_processing_errors(sdev))
980                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
981         }
982
983         return 0;
984
985 error_out:
986         scsi_autopm_put_device(sdev);
987 error_autopm:
988         scsi_disk_put(sdkp);
989         return retval;  
990 }
991
992 /**
993  *      sd_release - invoked when the (last) close(2) is called on this
994  *      scsi disk.
995  *      @inode: only i_rdev member may be used
996  *      @filp: only f_mode and f_flags may be used
997  *
998  *      Returns 0. 
999  *
1000  *      Note: may block (uninterruptible) if error recovery is underway
1001  *      on this disk.
1002  *
1003  *      Locking: called with bdev->bd_mutex held.
1004  **/
1005 static int sd_release(struct gendisk *disk, fmode_t mode)
1006 {
1007         struct scsi_disk *sdkp = scsi_disk(disk);
1008         struct scsi_device *sdev = sdkp->device;
1009
1010         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
1011
1012         if (atomic_dec_return(&sdkp->openers) == 0 && sdev->removable) {
1013                 if (scsi_block_when_processing_errors(sdev))
1014                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
1015         }
1016
1017         /*
1018          * XXX and what if there are packets in flight and this close()
1019          * XXX is followed by a "rmmod sd_mod"?
1020          */
1021
1022         scsi_autopm_put_device(sdev);
1023         scsi_disk_put(sdkp);
1024         return 0;
1025 }
1026
1027 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1028 {
1029         struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
1030         struct scsi_device *sdp = sdkp->device;
1031         struct Scsi_Host *host = sdp->host;
1032         int diskinfo[4];
1033
1034         /* default to most commonly used values */
1035         diskinfo[0] = 0x40;     /* 1 << 6 */
1036         diskinfo[1] = 0x20;     /* 1 << 5 */
1037         diskinfo[2] = sdkp->capacity >> 11;
1038         
1039         /* override with calculated, extended default, or driver values */
1040         if (host->hostt->bios_param)
1041                 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
1042         else
1043                 scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
1044
1045         geo->heads = diskinfo[0];
1046         geo->sectors = diskinfo[1];
1047         geo->cylinders = diskinfo[2];
1048         return 0;
1049 }
1050
1051 /**
1052  *      sd_ioctl - process an ioctl
1053  *      @inode: only i_rdev/i_bdev members may be used
1054  *      @filp: only f_mode and f_flags may be used
1055  *      @cmd: ioctl command number
1056  *      @arg: this is third argument given to ioctl(2) system call.
1057  *      Often contains a pointer.
1058  *
1059  *      Returns 0 if successful (some ioctls return positive numbers on
1060  *      success as well). Returns a negated errno value in case of error.
1061  *
1062  *      Note: most ioctls are forward onto the block subsystem or further
1063  *      down in the scsi subsystem.
1064  **/
1065 static int sd_ioctl(struct block_device *bdev, fmode_t mode,
1066                     unsigned int cmd, unsigned long arg)
1067 {
1068         struct gendisk *disk = bdev->bd_disk;
1069         struct scsi_disk *sdkp = scsi_disk(disk);
1070         struct scsi_device *sdp = sdkp->device;
1071         void __user *p = (void __user *)arg;
1072         int error;
1073     
1074         SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
1075                                     "cmd=0x%x\n", disk->disk_name, cmd));
1076
1077         /*
1078          * If we are in the middle of error recovery, don't let anyone
1079          * else try and use this device.  Also, if error recovery fails, it
1080          * may try and take the device offline, in which case all further
1081          * access to the device is prohibited.
1082          */
1083         error = scsi_nonblockable_ioctl(sdp, cmd, p,
1084                                         (mode & FMODE_NDELAY) != 0);
1085         if (!scsi_block_when_processing_errors(sdp) || !error)
1086                 goto out;
1087
1088         /*
1089          * Send SCSI addressing ioctls directly to mid level, send other
1090          * ioctls to block level and then onto mid level if they can't be
1091          * resolved.
1092          */
1093         switch (cmd) {
1094                 case SCSI_IOCTL_GET_IDLUN:
1095                 case SCSI_IOCTL_GET_BUS_NUMBER:
1096                         error = scsi_ioctl(sdp, cmd, p);
1097                         break;
1098                 default:
1099                         error = scsi_cmd_ioctl(disk->queue, disk, mode, cmd, p);
1100                         if (error != -ENOTTY)
1101                                 break;
1102                         error = scsi_ioctl(sdp, cmd, p);
1103                         break;
1104         }
1105 out:
1106         return error;
1107 }
1108
1109 static void set_media_not_present(struct scsi_disk *sdkp)
1110 {
1111         if (sdkp->media_present)
1112                 sdkp->device->changed = 1;
1113
1114         if (sdkp->device->removable) {
1115                 sdkp->media_present = 0;
1116                 sdkp->capacity = 0;
1117         }
1118 }
1119
1120 static int media_not_present(struct scsi_disk *sdkp,
1121                              struct scsi_sense_hdr *sshdr)
1122 {
1123         if (!scsi_sense_valid(sshdr))
1124                 return 0;
1125
1126         /* not invoked for commands that could return deferred errors */
1127         switch (sshdr->sense_key) {
1128         case UNIT_ATTENTION:
1129         case NOT_READY:
1130                 /* medium not present */
1131                 if (sshdr->asc == 0x3A) {
1132                         set_media_not_present(sdkp);
1133                         return 1;
1134                 }
1135         }
1136         return 0;
1137 }
1138
1139 /**
1140  *      sd_check_events - check media events
1141  *      @disk: kernel device descriptor
1142  *      @clearing: disk events currently being cleared
1143  *
1144  *      Returns mask of DISK_EVENT_*.
1145  *
1146  *      Note: this function is invoked from the block subsystem.
1147  **/
1148 static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
1149 {
1150         struct scsi_disk *sdkp = scsi_disk(disk);
1151         struct scsi_device *sdp = sdkp->device;
1152         struct scsi_sense_hdr *sshdr = NULL;
1153         int retval;
1154
1155         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
1156
1157         /*
1158          * If the device is offline, don't send any commands - just pretend as
1159          * if the command failed.  If the device ever comes back online, we
1160          * can deal with it then.  It is only because of unrecoverable errors
1161          * that we would ever take a device offline in the first place.
1162          */
1163         if (!scsi_device_online(sdp)) {
1164                 set_media_not_present(sdkp);
1165                 goto out;
1166         }
1167
1168         /*
1169          * Using TEST_UNIT_READY enables differentiation between drive with
1170          * no cartridge loaded - NOT READY, drive with changed cartridge -
1171          * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
1172          *
1173          * Drives that auto spin down. eg iomega jaz 1G, will be started
1174          * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
1175          * sd_revalidate() is called.
1176          */
1177         retval = -ENODEV;
1178
1179         if (scsi_block_when_processing_errors(sdp)) {
1180                 sshdr  = kzalloc(sizeof(*sshdr), GFP_KERNEL);
1181                 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES,
1182                                               sshdr);
1183         }
1184
1185         /* failed to execute TUR, assume media not present */
1186         if (host_byte(retval)) {
1187                 set_media_not_present(sdkp);
1188                 goto out;
1189         }
1190
1191         if (media_not_present(sdkp, sshdr))
1192                 goto out;
1193
1194         /*
1195          * For removable scsi disk we have to recognise the presence
1196          * of a disk in the drive.
1197          */
1198         if (!sdkp->media_present)
1199                 sdp->changed = 1;
1200         sdkp->media_present = 1;
1201 out:
1202         /*
1203          * sdp->changed is set under the following conditions:
1204          *
1205          *      Medium present state has changed in either direction.
1206          *      Device has indicated UNIT_ATTENTION.
1207          */
1208         kfree(sshdr);
1209         retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
1210         sdp->changed = 0;
1211         return retval;
1212 }
1213
1214 static int sd_sync_cache(struct scsi_disk *sdkp)
1215 {
1216         int retries, res;
1217         struct scsi_device *sdp = sdkp->device;
1218         struct scsi_sense_hdr sshdr;
1219
1220         if (!scsi_device_online(sdp))
1221                 return -ENODEV;
1222
1223
1224         for (retries = 3; retries > 0; --retries) {
1225                 unsigned char cmd[10] = { 0 };
1226
1227                 cmd[0] = SYNCHRONIZE_CACHE;
1228                 /*
1229                  * Leave the rest of the command zero to indicate
1230                  * flush everything.
1231                  */
1232                 res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
1233                                        SD_FLUSH_TIMEOUT, SD_MAX_RETRIES, NULL);
1234                 if (res == 0)
1235                         break;
1236         }
1237
1238         if (res) {
1239                 sd_print_result(sdkp, res);
1240                 if (driver_byte(res) & DRIVER_SENSE)
1241                         sd_print_sense_hdr(sdkp, &sshdr);
1242         }
1243
1244         if (res)
1245                 return -EIO;
1246         return 0;
1247 }
1248
1249 static void sd_rescan(struct device *dev)
1250 {
1251         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
1252
1253         if (sdkp) {
1254                 revalidate_disk(sdkp->disk);
1255                 scsi_disk_put(sdkp);
1256         }
1257 }
1258
1259
1260 #ifdef CONFIG_COMPAT
1261 /* 
1262  * This gets directly called from VFS. When the ioctl 
1263  * is not recognized we go back to the other translation paths. 
1264  */
1265 static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
1266                            unsigned int cmd, unsigned long arg)
1267 {
1268         struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
1269
1270         /*
1271          * If we are in the middle of error recovery, don't let anyone
1272          * else try and use this device.  Also, if error recovery fails, it
1273          * may try and take the device offline, in which case all further
1274          * access to the device is prohibited.
1275          */
1276         if (!scsi_block_when_processing_errors(sdev))
1277                 return -ENODEV;
1278                
1279         if (sdev->host->hostt->compat_ioctl) {
1280                 int ret;
1281
1282                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
1283
1284                 return ret;
1285         }
1286
1287         /* 
1288          * Let the static ioctl translation table take care of it.
1289          */
1290         return -ENOIOCTLCMD; 
1291 }
1292 #endif
1293
1294 static const struct block_device_operations sd_fops = {
1295         .owner                  = THIS_MODULE,
1296         .open                   = sd_open,
1297         .release                = sd_release,
1298         .ioctl                  = sd_ioctl,
1299         .getgeo                 = sd_getgeo,
1300 #ifdef CONFIG_COMPAT
1301         .compat_ioctl           = sd_compat_ioctl,
1302 #endif
1303         .check_events           = sd_check_events,
1304         .revalidate_disk        = sd_revalidate_disk,
1305         .unlock_native_capacity = sd_unlock_native_capacity,
1306 };
1307
1308 static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
1309 {
1310         u64 start_lba = blk_rq_pos(scmd->request);
1311         u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
1312         u64 bad_lba;
1313         int info_valid;
1314         /*
1315          * resid is optional but mostly filled in.  When it's unused,
1316          * its value is zero, so we assume the whole buffer transferred
1317          */
1318         unsigned int transferred = scsi_bufflen(scmd) - scsi_get_resid(scmd);
1319         unsigned int good_bytes;
1320
1321         if (scmd->request->cmd_type != REQ_TYPE_FS)
1322                 return 0;
1323
1324         info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
1325                                              SCSI_SENSE_BUFFERSIZE,
1326                                              &bad_lba);
1327         if (!info_valid)
1328                 return 0;
1329
1330         if (scsi_bufflen(scmd) <= scmd->device->sector_size)
1331                 return 0;
1332
1333         if (scmd->device->sector_size < 512) {
1334                 /* only legitimate sector_size here is 256 */
1335                 start_lba <<= 1;
1336                 end_lba <<= 1;
1337         } else {
1338                 /* be careful ... don't want any overflows */
1339                 u64 factor = scmd->device->sector_size / 512;
1340                 do_div(start_lba, factor);
1341                 do_div(end_lba, factor);
1342         }
1343
1344         /* The bad lba was reported incorrectly, we have no idea where
1345          * the error is.
1346          */
1347         if (bad_lba < start_lba  || bad_lba >= end_lba)
1348                 return 0;
1349
1350         /* This computation should always be done in terms of
1351          * the resolution of the device's medium.
1352          */
1353         good_bytes = (bad_lba - start_lba) * scmd->device->sector_size;
1354         return min(good_bytes, transferred);
1355 }
1356
1357 /**
1358  *      sd_done - bottom half handler: called when the lower level
1359  *      driver has completed (successfully or otherwise) a scsi command.
1360  *      @SCpnt: mid-level's per command structure.
1361  *
1362  *      Note: potentially run from within an ISR. Must not block.
1363  **/
1364 static int sd_done(struct scsi_cmnd *SCpnt)
1365 {
1366         int result = SCpnt->result;
1367         unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
1368         struct scsi_sense_hdr sshdr;
1369         struct scsi_disk *sdkp = scsi_disk(SCpnt->request->rq_disk);
1370         int sense_valid = 0;
1371         int sense_deferred = 0;
1372         unsigned char op = SCpnt->cmnd[0];
1373
1374         if ((SCpnt->request->cmd_flags & REQ_DISCARD) && !result)
1375                 scsi_set_resid(SCpnt, 0);
1376
1377         if (result) {
1378                 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
1379                 if (sense_valid)
1380                         sense_deferred = scsi_sense_is_deferred(&sshdr);
1381         }
1382 #ifdef CONFIG_SCSI_LOGGING
1383         SCSI_LOG_HLCOMPLETE(1, scsi_print_result(SCpnt));
1384         if (sense_valid) {
1385                 SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
1386                                                    "sd_done: sb[respc,sk,asc,"
1387                                                    "ascq]=%x,%x,%x,%x\n",
1388                                                    sshdr.response_code,
1389                                                    sshdr.sense_key, sshdr.asc,
1390                                                    sshdr.ascq));
1391         }
1392 #endif
1393         if (driver_byte(result) != DRIVER_SENSE &&
1394             (!sense_valid || sense_deferred))
1395                 goto out;
1396
1397         switch (sshdr.sense_key) {
1398         case HARDWARE_ERROR:
1399         case MEDIUM_ERROR:
1400                 good_bytes = sd_completed_bytes(SCpnt);
1401                 break;
1402         case RECOVERED_ERROR:
1403                 good_bytes = scsi_bufflen(SCpnt);
1404                 break;
1405         case NO_SENSE:
1406                 /* This indicates a false check condition, so ignore it.  An
1407                  * unknown amount of data was transferred so treat it as an
1408                  * error.
1409                  */
1410                 scsi_print_sense("sd", SCpnt);
1411                 SCpnt->result = 0;
1412                 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1413                 break;
1414         case ABORTED_COMMAND:
1415                 if (sshdr.asc == 0x10)  /* DIF: Target detected corruption */
1416                         good_bytes = sd_completed_bytes(SCpnt);
1417                 break;
1418         case ILLEGAL_REQUEST:
1419                 if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
1420                         good_bytes = sd_completed_bytes(SCpnt);
1421                 /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
1422                 if ((sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1423                     (op == UNMAP || op == WRITE_SAME_16 || op == WRITE_SAME))
1424                         sd_config_discard(sdkp, SD_LBP_DISABLE);
1425                 break;
1426         default:
1427                 break;
1428         }
1429  out:
1430         if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
1431                 sd_dif_complete(SCpnt, good_bytes);
1432
1433         if (scsi_host_dif_capable(sdkp->device->host, sdkp->protection_type)
1434             == SD_DIF_TYPE2_PROTECTION && SCpnt->cmnd != SCpnt->request->cmd) {
1435
1436                 /* We have to print a failed command here as the
1437                  * extended CDB gets freed before scsi_io_completion()
1438                  * is called.
1439                  */
1440                 if (result)
1441                         scsi_print_command(SCpnt);
1442
1443                 mempool_free(SCpnt->cmnd, sd_cdb_pool);
1444                 SCpnt->cmnd = NULL;
1445                 SCpnt->cmd_len = 0;
1446         }
1447
1448         return good_bytes;
1449 }
1450
1451 /*
1452  * spinup disk - called only in sd_revalidate_disk()
1453  */
1454 static void
1455 sd_spinup_disk(struct scsi_disk *sdkp)
1456 {
1457         unsigned char cmd[10];
1458         unsigned long spintime_expire = 0;
1459         int retries, spintime;
1460         unsigned int the_result;
1461         struct scsi_sense_hdr sshdr;
1462         int sense_valid = 0;
1463
1464         spintime = 0;
1465
1466         /* Spin up drives, as required.  Only do this at boot time */
1467         /* Spinup needs to be done for module loads too. */
1468         do {
1469                 retries = 0;
1470
1471                 do {
1472                         cmd[0] = TEST_UNIT_READY;
1473                         memset((void *) &cmd[1], 0, 9);
1474
1475                         the_result = scsi_execute_req(sdkp->device, cmd,
1476                                                       DMA_NONE, NULL, 0,
1477                                                       &sshdr, SD_TIMEOUT,
1478                                                       SD_MAX_RETRIES, NULL);
1479
1480                         /*
1481                          * If the drive has indicated to us that it
1482                          * doesn't have any media in it, don't bother
1483                          * with any more polling.
1484                          */
1485                         if (media_not_present(sdkp, &sshdr))
1486                                 return;
1487
1488                         if (the_result)
1489                                 sense_valid = scsi_sense_valid(&sshdr);
1490                         retries++;
1491                 } while (retries < 3 && 
1492                          (!scsi_status_is_good(the_result) ||
1493                           ((driver_byte(the_result) & DRIVER_SENSE) &&
1494                           sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
1495
1496                 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
1497                         /* no sense, TUR either succeeded or failed
1498                          * with a status error */
1499                         if(!spintime && !scsi_status_is_good(the_result)) {
1500                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1501                                 sd_print_result(sdkp, the_result);
1502                         }
1503                         break;
1504                 }
1505                                         
1506                 /*
1507                  * The device does not want the automatic start to be issued.
1508                  */
1509                 if (sdkp->device->no_start_on_add)
1510                         break;
1511
1512                 if (sense_valid && sshdr.sense_key == NOT_READY) {
1513                         if (sshdr.asc == 4 && sshdr.ascq == 3)
1514                                 break;  /* manual intervention required */
1515                         if (sshdr.asc == 4 && sshdr.ascq == 0xb)
1516                                 break;  /* standby */
1517                         if (sshdr.asc == 4 && sshdr.ascq == 0xc)
1518                                 break;  /* unavailable */
1519                         /*
1520                          * Issue command to spin up drive when not ready
1521                          */
1522                         if (!spintime) {
1523                                 sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
1524                                 cmd[0] = START_STOP;
1525                                 cmd[1] = 1;     /* Return immediately */
1526                                 memset((void *) &cmd[2], 0, 8);
1527                                 cmd[4] = 1;     /* Start spin cycle */
1528                                 if (sdkp->device->start_stop_pwr_cond)
1529                                         cmd[4] |= 1 << 4;
1530                                 scsi_execute_req(sdkp->device, cmd, DMA_NONE,
1531                                                  NULL, 0, &sshdr,
1532                                                  SD_TIMEOUT, SD_MAX_RETRIES,
1533                                                  NULL);
1534                                 spintime_expire = jiffies + 100 * HZ;
1535                                 spintime = 1;
1536                         }
1537                         /* Wait 1 second for next try */
1538                         msleep(1000);
1539                         printk(".");
1540
1541                 /*
1542                  * Wait for USB flash devices with slow firmware.
1543                  * Yes, this sense key/ASC combination shouldn't
1544                  * occur here.  It's characteristic of these devices.
1545                  */
1546                 } else if (sense_valid &&
1547                                 sshdr.sense_key == UNIT_ATTENTION &&
1548                                 sshdr.asc == 0x28) {
1549                         if (!spintime) {
1550                                 spintime_expire = jiffies + 5 * HZ;
1551                                 spintime = 1;
1552                         }
1553                         /* Wait 1 second for next try */
1554                         msleep(1000);
1555                 } else {
1556                         /* we don't understand the sense code, so it's
1557                          * probably pointless to loop */
1558                         if(!spintime) {
1559                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1560                                 sd_print_sense_hdr(sdkp, &sshdr);
1561                         }
1562                         break;
1563                 }
1564                                 
1565         } while (spintime && time_before_eq(jiffies, spintime_expire));
1566
1567         if (spintime) {
1568                 if (scsi_status_is_good(the_result))
1569                         printk("ready\n");
1570                 else
1571                         printk("not responding...\n");
1572         }
1573 }
1574
1575
1576 /*
1577  * Determine whether disk supports Data Integrity Field.
1578  */
1579 static void sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
1580 {
1581         struct scsi_device *sdp = sdkp->device;
1582         u8 type;
1583
1584         if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
1585                 return;
1586
1587         type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
1588
1589         if (type == sdkp->protection_type || !sdkp->first_scan)
1590                 return;
1591
1592         sdkp->protection_type = type;
1593
1594         if (type > SD_DIF_TYPE3_PROTECTION) {
1595                 sd_printk(KERN_ERR, sdkp, "formatted with unsupported " \
1596                           "protection type %u. Disabling disk!\n", type);
1597                 sdkp->capacity = 0;
1598                 return;
1599         }
1600
1601         if (scsi_host_dif_capable(sdp->host, type))
1602                 sd_printk(KERN_NOTICE, sdkp,
1603                           "Enabling DIF Type %u protection\n", type);
1604         else
1605                 sd_printk(KERN_NOTICE, sdkp,
1606                           "Disabling DIF Type %u protection\n", type);
1607 }
1608
1609 static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
1610                         struct scsi_sense_hdr *sshdr, int sense_valid,
1611                         int the_result)
1612 {
1613         sd_print_result(sdkp, the_result);
1614         if (driver_byte(the_result) & DRIVER_SENSE)
1615                 sd_print_sense_hdr(sdkp, sshdr);
1616         else
1617                 sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
1618
1619         /*
1620          * Set dirty bit for removable devices if not ready -
1621          * sometimes drives will not report this properly.
1622          */
1623         if (sdp->removable &&
1624             sense_valid && sshdr->sense_key == NOT_READY)
1625                 set_media_not_present(sdkp);
1626
1627         /*
1628          * We used to set media_present to 0 here to indicate no media
1629          * in the drive, but some drives fail read capacity even with
1630          * media present, so we can't do that.
1631          */
1632         sdkp->capacity = 0; /* unknown mapped to zero - as usual */
1633 }
1634
1635 #define RC16_LEN 32
1636 #if RC16_LEN > SD_BUF_SIZE
1637 #error RC16_LEN must not be more than SD_BUF_SIZE
1638 #endif
1639
1640 #define READ_CAPACITY_RETRIES_ON_RESET  10
1641
1642 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
1643                                                 unsigned char *buffer)
1644 {
1645         unsigned char cmd[16];
1646         struct scsi_sense_hdr sshdr;
1647         int sense_valid = 0;
1648         int the_result;
1649         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1650         unsigned int alignment;
1651         unsigned long long lba;
1652         unsigned sector_size;
1653
1654         if (sdp->no_read_capacity_16)
1655                 return -EINVAL;
1656
1657         do {
1658                 memset(cmd, 0, 16);
1659                 cmd[0] = SERVICE_ACTION_IN;
1660                 cmd[1] = SAI_READ_CAPACITY_16;
1661                 cmd[13] = RC16_LEN;
1662                 memset(buffer, 0, RC16_LEN);
1663
1664                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1665                                         buffer, RC16_LEN, &sshdr,
1666                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1667
1668                 if (media_not_present(sdkp, &sshdr))
1669                         return -ENODEV;
1670
1671                 if (the_result) {
1672                         sense_valid = scsi_sense_valid(&sshdr);
1673                         if (sense_valid &&
1674                             sshdr.sense_key == ILLEGAL_REQUEST &&
1675                             (sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1676                             sshdr.ascq == 0x00)
1677                                 /* Invalid Command Operation Code or
1678                                  * Invalid Field in CDB, just retry
1679                                  * silently with RC10 */
1680                                 return -EINVAL;
1681                         if (sense_valid &&
1682                             sshdr.sense_key == UNIT_ATTENTION &&
1683                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1684                                 /* Device reset might occur several times,
1685                                  * give it one more chance */
1686                                 if (--reset_retries > 0)
1687                                         continue;
1688                 }
1689                 retries--;
1690
1691         } while (the_result && retries);
1692
1693         if (the_result) {
1694                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY(16) failed\n");
1695                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1696                 return -EINVAL;
1697         }
1698
1699         sector_size = get_unaligned_be32(&buffer[8]);
1700         lba = get_unaligned_be64(&buffer[0]);
1701
1702         sd_read_protection_type(sdkp, buffer);
1703
1704         if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
1705                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1706                         "kernel compiled with support for large block "
1707                         "devices.\n");
1708                 sdkp->capacity = 0;
1709                 return -EOVERFLOW;
1710         }
1711
1712         /* Logical blocks per physical block exponent */
1713         sdkp->physical_block_size = (1 << (buffer[13] & 0xf)) * sector_size;
1714
1715         /* Lowest aligned logical block */
1716         alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size;
1717         blk_queue_alignment_offset(sdp->request_queue, alignment);
1718         if (alignment && sdkp->first_scan)
1719                 sd_printk(KERN_NOTICE, sdkp,
1720                           "physical block alignment offset: %u\n", alignment);
1721
1722         if (buffer[14] & 0x80) { /* LBPME */
1723                 sdkp->lbpme = 1;
1724
1725                 if (buffer[14] & 0x40) /* LBPRZ */
1726                         sdkp->lbprz = 1;
1727
1728                 sd_config_discard(sdkp, SD_LBP_WS16);
1729         }
1730
1731         sdkp->capacity = lba + 1;
1732         return sector_size;
1733 }
1734
1735 static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
1736                                                 unsigned char *buffer)
1737 {
1738         unsigned char cmd[16];
1739         struct scsi_sense_hdr sshdr;
1740         int sense_valid = 0;
1741         int the_result;
1742         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1743         sector_t lba;
1744         unsigned sector_size;
1745
1746         do {
1747                 cmd[0] = READ_CAPACITY;
1748                 memset(&cmd[1], 0, 9);
1749                 memset(buffer, 0, 8);
1750
1751                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1752                                         buffer, 8, &sshdr,
1753                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1754
1755                 if (media_not_present(sdkp, &sshdr))
1756                         return -ENODEV;
1757
1758                 if (the_result) {
1759                         sense_valid = scsi_sense_valid(&sshdr);
1760                         if (sense_valid &&
1761                             sshdr.sense_key == UNIT_ATTENTION &&
1762                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1763                                 /* Device reset might occur several times,
1764                                  * give it one more chance */
1765                                 if (--reset_retries > 0)
1766                                         continue;
1767                 }
1768                 retries--;
1769
1770         } while (the_result && retries);
1771
1772         if (the_result) {
1773                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY failed\n");
1774                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1775                 return -EINVAL;
1776         }
1777
1778         sector_size = get_unaligned_be32(&buffer[4]);
1779         lba = get_unaligned_be32(&buffer[0]);
1780
1781         if (sdp->no_read_capacity_16 && (lba == 0xffffffff)) {
1782                 /* Some buggy (usb cardreader) devices return an lba of
1783                    0xffffffff when the want to report a size of 0 (with
1784                    which they really mean no media is present) */
1785                 sdkp->capacity = 0;
1786                 sdkp->physical_block_size = sector_size;
1787                 return sector_size;
1788         }
1789
1790         if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
1791                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1792                         "kernel compiled with support for large block "
1793                         "devices.\n");
1794                 sdkp->capacity = 0;
1795                 return -EOVERFLOW;
1796         }
1797
1798         sdkp->capacity = lba + 1;
1799         sdkp->physical_block_size = sector_size;
1800         return sector_size;
1801 }
1802
1803 static int sd_try_rc16_first(struct scsi_device *sdp)
1804 {
1805         if (sdp->host->max_cmd_len < 16)
1806                 return 0;
1807         if (sdp->scsi_level > SCSI_SPC_2)
1808                 return 1;
1809         if (scsi_device_protection(sdp))
1810                 return 1;
1811         return 0;
1812 }
1813
1814 /*
1815  * read disk capacity
1816  */
1817 static void
1818 sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
1819 {
1820         int sector_size;
1821         struct scsi_device *sdp = sdkp->device;
1822         sector_t old_capacity = sdkp->capacity;
1823
1824         if (sd_try_rc16_first(sdp)) {
1825                 sector_size = read_capacity_16(sdkp, sdp, buffer);
1826                 if (sector_size == -EOVERFLOW)
1827                         goto got_data;
1828                 if (sector_size == -ENODEV)
1829                         return;
1830                 if (sector_size < 0)
1831                         sector_size = read_capacity_10(sdkp, sdp, buffer);
1832                 if (sector_size < 0)
1833                         return;
1834         } else {
1835                 sector_size = read_capacity_10(sdkp, sdp, buffer);
1836                 if (sector_size == -EOVERFLOW)
1837                         goto got_data;
1838                 if (sector_size < 0)
1839                         return;
1840                 if ((sizeof(sdkp->capacity) > 4) &&
1841                     (sdkp->capacity > 0xffffffffULL)) {
1842                         int old_sector_size = sector_size;
1843                         sd_printk(KERN_NOTICE, sdkp, "Very big device. "
1844                                         "Trying to use READ CAPACITY(16).\n");
1845                         sector_size = read_capacity_16(sdkp, sdp, buffer);
1846                         if (sector_size < 0) {
1847                                 sd_printk(KERN_NOTICE, sdkp,
1848                                         "Using 0xffffffff as device size\n");
1849                                 sdkp->capacity = 1 + (sector_t) 0xffffffff;
1850                                 sector_size = old_sector_size;
1851                                 goto got_data;
1852                         }
1853                 }
1854         }
1855
1856         /* Some devices are known to return the total number of blocks,
1857          * not the highest block number.  Some devices have versions
1858          * which do this and others which do not.  Some devices we might
1859          * suspect of doing this but we don't know for certain.
1860          *
1861          * If we know the reported capacity is wrong, decrement it.  If
1862          * we can only guess, then assume the number of blocks is even
1863          * (usually true but not always) and err on the side of lowering
1864          * the capacity.
1865          */
1866         if (sdp->fix_capacity ||
1867             (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
1868                 sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
1869                                 "from its reported value: %llu\n",
1870                                 (unsigned long long) sdkp->capacity);
1871                 --sdkp->capacity;
1872         }
1873
1874 got_data:
1875         if (sector_size == 0) {
1876                 sector_size = 512;
1877                 sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
1878                           "assuming 512.\n");
1879         }
1880
1881         if (sector_size != 512 &&
1882             sector_size != 1024 &&
1883             sector_size != 2048 &&
1884             sector_size != 4096 &&
1885             sector_size != 256) {
1886                 sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
1887                           sector_size);
1888                 /*
1889                  * The user might want to re-format the drive with
1890                  * a supported sectorsize.  Once this happens, it
1891                  * would be relatively trivial to set the thing up.
1892                  * For this reason, we leave the thing in the table.
1893                  */
1894                 sdkp->capacity = 0;
1895                 /*
1896                  * set a bogus sector size so the normal read/write
1897                  * logic in the block layer will eventually refuse any
1898                  * request on this device without tripping over power
1899                  * of two sector size assumptions
1900                  */
1901                 sector_size = 512;
1902         }
1903         blk_queue_logical_block_size(sdp->request_queue, sector_size);
1904
1905         {
1906                 char cap_str_2[10], cap_str_10[10];
1907                 u64 sz = (u64)sdkp->capacity << ilog2(sector_size);
1908
1909                 string_get_size(sz, STRING_UNITS_2, cap_str_2,
1910                                 sizeof(cap_str_2));
1911                 string_get_size(sz, STRING_UNITS_10, cap_str_10,
1912                                 sizeof(cap_str_10));
1913
1914                 if (sdkp->first_scan || old_capacity != sdkp->capacity) {
1915                         sd_printk(KERN_NOTICE, sdkp,
1916                                   "%llu %d-byte logical blocks: (%s/%s)\n",
1917                                   (unsigned long long)sdkp->capacity,
1918                                   sector_size, cap_str_10, cap_str_2);
1919
1920                         if (sdkp->physical_block_size != sector_size)
1921                                 sd_printk(KERN_NOTICE, sdkp,
1922                                           "%u-byte physical blocks\n",
1923                                           sdkp->physical_block_size);
1924                 }
1925         }
1926
1927         /* Rescale capacity to 512-byte units */
1928         if (sector_size == 4096)
1929                 sdkp->capacity <<= 3;
1930         else if (sector_size == 2048)
1931                 sdkp->capacity <<= 2;
1932         else if (sector_size == 1024)
1933                 sdkp->capacity <<= 1;
1934         else if (sector_size == 256)
1935                 sdkp->capacity >>= 1;
1936
1937         blk_queue_physical_block_size(sdp->request_queue,
1938                                       sdkp->physical_block_size);
1939         sdkp->device->sector_size = sector_size;
1940 }
1941
1942 /* called with buffer of length 512 */
1943 static inline int
1944 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
1945                  unsigned char *buffer, int len, struct scsi_mode_data *data,
1946                  struct scsi_sense_hdr *sshdr)
1947 {
1948         return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
1949                                SD_TIMEOUT, SD_MAX_RETRIES, data,
1950                                sshdr);
1951 }
1952
1953 /*
1954  * read write protect setting, if possible - called only in sd_revalidate_disk()
1955  * called with buffer of length SD_BUF_SIZE
1956  */
1957 static void
1958 sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
1959 {
1960         int res;
1961         struct scsi_device *sdp = sdkp->device;
1962         struct scsi_mode_data data;
1963         int old_wp = sdkp->write_prot;
1964
1965         set_disk_ro(sdkp->disk, 0);
1966         if (sdp->skip_ms_page_3f) {
1967                 sd_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
1968                 return;
1969         }
1970
1971         if (sdp->use_192_bytes_for_3f) {
1972                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
1973         } else {
1974                 /*
1975                  * First attempt: ask for all pages (0x3F), but only 4 bytes.
1976                  * We have to start carefully: some devices hang if we ask
1977                  * for more than is available.
1978                  */
1979                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
1980
1981                 /*
1982                  * Second attempt: ask for page 0 When only page 0 is
1983                  * implemented, a request for page 3F may return Sense Key
1984                  * 5: Illegal Request, Sense Code 24: Invalid field in
1985                  * CDB.
1986                  */
1987                 if (!scsi_status_is_good(res))
1988                         res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
1989
1990                 /*
1991                  * Third attempt: ask 255 bytes, as we did earlier.
1992                  */
1993                 if (!scsi_status_is_good(res))
1994                         res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
1995                                                &data, NULL);
1996         }
1997
1998         if (!scsi_status_is_good(res)) {
1999                 sd_printk(KERN_WARNING, sdkp,
2000                           "Test WP failed, assume Write Enabled\n");
2001         } else {
2002                 sdkp->write_prot = ((data.device_specific & 0x80) != 0);
2003                 set_disk_ro(sdkp->disk, sdkp->write_prot);
2004                 if (sdkp->first_scan || old_wp != sdkp->write_prot) {
2005                         sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
2006                                   sdkp->write_prot ? "on" : "off");
2007                         sd_printk(KERN_DEBUG, sdkp,
2008                                   "Mode Sense: %02x %02x %02x %02x\n",
2009                                   buffer[0], buffer[1], buffer[2], buffer[3]);
2010                 }
2011         }
2012 }
2013
2014 /*
2015  * sd_read_cache_type - called only from sd_revalidate_disk()
2016  * called with buffer of length SD_BUF_SIZE
2017  */
2018 static void
2019 sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
2020 {
2021         int len = 0, res;
2022         struct scsi_device *sdp = sdkp->device;
2023
2024         int dbd;
2025         int modepage;
2026         int first_len;
2027         struct scsi_mode_data data;
2028         struct scsi_sense_hdr sshdr;
2029         int old_wce = sdkp->WCE;
2030         int old_rcd = sdkp->RCD;
2031         int old_dpofua = sdkp->DPOFUA;
2032
2033         first_len = 4;
2034         if (sdp->skip_ms_page_8) {
2035                 if (sdp->type == TYPE_RBC)
2036                         goto defaults;
2037                 else {
2038                         if (sdp->skip_ms_page_3f)
2039                                 goto defaults;
2040                         modepage = 0x3F;
2041                         if (sdp->use_192_bytes_for_3f)
2042                                 first_len = 192;
2043                         dbd = 0;
2044                 }
2045         } else if (sdp->type == TYPE_RBC) {
2046                 modepage = 6;
2047                 dbd = 8;
2048         } else {
2049                 modepage = 8;
2050                 dbd = 0;
2051         }
2052
2053         /* cautiously ask */
2054         res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len,
2055                         &data, &sshdr);
2056
2057         if (!scsi_status_is_good(res))
2058                 goto bad_sense;
2059
2060         if (!data.header_length) {
2061                 modepage = 6;
2062                 first_len = 0;
2063                 sd_printk(KERN_ERR, sdkp, "Missing header in MODE_SENSE response\n");
2064         }
2065
2066         /* that went OK, now ask for the proper length */
2067         len = data.length;
2068
2069         /*
2070          * We're only interested in the first three bytes, actually.
2071          * But the data cache page is defined for the first 20.
2072          */
2073         if (len < 3)
2074                 goto bad_sense;
2075         else if (len > SD_BUF_SIZE) {
2076                 sd_printk(KERN_NOTICE, sdkp, "Truncating mode parameter "
2077                           "data from %d to %d bytes\n", len, SD_BUF_SIZE);
2078                 len = SD_BUF_SIZE;
2079         }
2080         if (modepage == 0x3F && sdp->use_192_bytes_for_3f)
2081                 len = 192;
2082
2083         /* Get the data */
2084         if (len > first_len)
2085                 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len,
2086                                 &data, &sshdr);
2087
2088         if (scsi_status_is_good(res)) {
2089                 int offset = data.header_length + data.block_descriptor_length;
2090
2091                 while (offset < len) {
2092                         u8 page_code = buffer[offset] & 0x3F;
2093                         u8 spf       = buffer[offset] & 0x40;
2094
2095                         if (page_code == 8 || page_code == 6) {
2096                                 /* We're interested only in the first 3 bytes.
2097                                  */
2098                                 if (len - offset <= 2) {
2099                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2100                                                   "mode parameter data\n");
2101                                         goto defaults;
2102                                 } else {
2103                                         modepage = page_code;
2104                                         goto Page_found;
2105                                 }
2106                         } else {
2107                                 /* Go to the next page */
2108                                 if (spf && len - offset > 3)
2109                                         offset += 4 + (buffer[offset+2] << 8) +
2110                                                 buffer[offset+3];
2111                                 else if (!spf && len - offset > 1)
2112                                         offset += 2 + buffer[offset+1];
2113                                 else {
2114                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2115                                                   "mode parameter data\n");
2116                                         goto defaults;
2117                                 }
2118                         }
2119                 }
2120
2121                 if (modepage == 0x3F) {
2122                         sd_printk(KERN_ERR, sdkp, "No Caching mode page "
2123                                   "present\n");
2124                         goto defaults;
2125                 } else if ((buffer[offset] & 0x3f) != modepage) {
2126                         sd_printk(KERN_ERR, sdkp, "Got wrong page\n");
2127                         goto defaults;
2128                 }
2129         Page_found:
2130                 if (modepage == 8) {
2131                         sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
2132                         sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
2133                 } else {
2134                         sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
2135                         sdkp->RCD = 0;
2136                 }
2137
2138                 sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
2139                 if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
2140                         sd_printk(KERN_NOTICE, sdkp,
2141                                   "Uses READ/WRITE(6), disabling FUA\n");
2142                         sdkp->DPOFUA = 0;
2143                 }
2144
2145                 if (sdkp->first_scan || old_wce != sdkp->WCE ||
2146                     old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
2147                         sd_printk(KERN_NOTICE, sdkp,
2148                                   "Write cache: %s, read cache: %s, %s\n",
2149                                   sdkp->WCE ? "enabled" : "disabled",
2150                                   sdkp->RCD ? "disabled" : "enabled",
2151                                   sdkp->DPOFUA ? "supports DPO and FUA"
2152                                   : "doesn't support DPO or FUA");
2153
2154                 return;
2155         }
2156
2157 bad_sense:
2158         if (scsi_sense_valid(&sshdr) &&
2159             sshdr.sense_key == ILLEGAL_REQUEST &&
2160             sshdr.asc == 0x24 && sshdr.ascq == 0x0)
2161                 /* Invalid field in CDB */
2162                 sd_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
2163         else
2164                 sd_printk(KERN_ERR, sdkp, "Asking for cache data failed\n");
2165
2166 defaults:
2167         sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n");
2168         sdkp->WCE = 0;
2169         sdkp->RCD = 0;
2170         sdkp->DPOFUA = 0;
2171 }
2172
2173 /*
2174  * The ATO bit indicates whether the DIF application tag is available
2175  * for use by the operating system.
2176  */
2177 static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
2178 {
2179         int res, offset;
2180         struct scsi_device *sdp = sdkp->device;
2181         struct scsi_mode_data data;
2182         struct scsi_sense_hdr sshdr;
2183
2184         if (sdp->type != TYPE_DISK)
2185                 return;
2186
2187         if (sdkp->protection_type == 0)
2188                 return;
2189
2190         res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
2191                               SD_MAX_RETRIES, &data, &sshdr);
2192
2193         if (!scsi_status_is_good(res) || !data.header_length ||
2194             data.length < 6) {
2195                 sd_printk(KERN_WARNING, sdkp,
2196                           "getting Control mode page failed, assume no ATO\n");
2197
2198                 if (scsi_sense_valid(&sshdr))
2199                         sd_print_sense_hdr(sdkp, &sshdr);
2200
2201                 return;
2202         }
2203
2204         offset = data.header_length + data.block_descriptor_length;
2205
2206         if ((buffer[offset] & 0x3f) != 0x0a) {
2207                 sd_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
2208                 return;
2209         }
2210
2211         if ((buffer[offset + 5] & 0x80) == 0)
2212                 return;
2213
2214         sdkp->ATO = 1;
2215
2216         return;
2217 }
2218
2219 /**
2220  * sd_read_block_limits - Query disk device for preferred I/O sizes.
2221  * @disk: disk to query
2222  */
2223 static void sd_read_block_limits(struct scsi_disk *sdkp)
2224 {
2225         unsigned int sector_sz = sdkp->device->sector_size;
2226         const int vpd_len = 64;
2227         unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
2228
2229         if (!buffer ||
2230             /* Block Limits VPD */
2231             scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
2232                 goto out;
2233
2234         blk_queue_io_min(sdkp->disk->queue,
2235                          get_unaligned_be16(&buffer[6]) * sector_sz);
2236         blk_queue_io_opt(sdkp->disk->queue,
2237                          get_unaligned_be32(&buffer[12]) * sector_sz);
2238
2239         if (buffer[3] == 0x3c) {
2240                 unsigned int lba_count, desc_count;
2241
2242                 sdkp->max_ws_blocks =
2243                         (u32) min_not_zero(get_unaligned_be64(&buffer[36]),
2244                                            (u64)0xffffffff);
2245
2246                 if (!sdkp->lbpme)
2247                         goto out;
2248
2249                 lba_count = get_unaligned_be32(&buffer[20]);
2250                 desc_count = get_unaligned_be32(&buffer[24]);
2251
2252                 if (lba_count && desc_count)
2253                         sdkp->max_unmap_blocks = lba_count;
2254
2255                 sdkp->unmap_granularity = get_unaligned_be32(&buffer[28]);
2256
2257                 if (buffer[32] & 0x80)
2258                         sdkp->unmap_alignment =
2259                                 get_unaligned_be32(&buffer[32]) & ~(1 << 31);
2260
2261                 if (!sdkp->lbpvpd) { /* LBP VPD page not provided */
2262
2263                         if (sdkp->max_unmap_blocks)
2264                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2265                         else
2266                                 sd_config_discard(sdkp, SD_LBP_WS16);
2267
2268                 } else {        /* LBP VPD page tells us what to use */
2269
2270                         if (sdkp->lbpu && sdkp->max_unmap_blocks)
2271                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2272                         else if (sdkp->lbpws)
2273                                 sd_config_discard(sdkp, SD_LBP_WS16);
2274                         else if (sdkp->lbpws10)
2275                                 sd_config_discard(sdkp, SD_LBP_WS10);
2276                         else
2277                                 sd_config_discard(sdkp, SD_LBP_DISABLE);
2278                 }
2279         }
2280
2281  out:
2282         kfree(buffer);
2283 }
2284
2285 /**
2286  * sd_read_block_characteristics - Query block dev. characteristics
2287  * @disk: disk to query
2288  */
2289 static void sd_read_block_characteristics(struct scsi_disk *sdkp)
2290 {
2291         unsigned char *buffer;
2292         u16 rot;
2293         const int vpd_len = 64;
2294
2295         buffer = kmalloc(vpd_len, GFP_KERNEL);
2296
2297         if (!buffer ||
2298             /* Block Device Characteristics VPD */
2299             scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
2300                 goto out;
2301
2302         rot = get_unaligned_be16(&buffer[4]);
2303
2304         if (rot == 1)
2305                 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
2306
2307  out:
2308         kfree(buffer);
2309 }
2310
2311 /**
2312  * sd_read_block_provisioning - Query provisioning VPD page
2313  * @disk: disk to query
2314  */
2315 static void sd_read_block_provisioning(struct scsi_disk *sdkp)
2316 {
2317         unsigned char *buffer;
2318         const int vpd_len = 8;
2319
2320         if (sdkp->lbpme == 0)
2321                 return;
2322
2323         buffer = kmalloc(vpd_len, GFP_KERNEL);
2324
2325         if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
2326                 goto out;
2327
2328         sdkp->lbpvpd    = 1;
2329         sdkp->lbpu      = (buffer[5] >> 7) & 1; /* UNMAP */
2330         sdkp->lbpws     = (buffer[5] >> 6) & 1; /* WRITE SAME(16) with UNMAP */
2331         sdkp->lbpws10   = (buffer[5] >> 5) & 1; /* WRITE SAME(10) with UNMAP */
2332
2333  out:
2334         kfree(buffer);
2335 }
2336
2337 static int sd_try_extended_inquiry(struct scsi_device *sdp)
2338 {
2339         /*
2340          * Although VPD inquiries can go to SCSI-2 type devices,
2341          * some USB ones crash on receiving them, and the pages
2342          * we currently ask for are for SPC-3 and beyond
2343          */
2344         if (sdp->scsi_level > SCSI_SPC_2)
2345                 return 1;
2346         return 0;
2347 }
2348
2349 /**
2350  *      sd_revalidate_disk - called the first time a new disk is seen,
2351  *      performs disk spin up, read_capacity, etc.
2352  *      @disk: struct gendisk we care about
2353  **/
2354 static int sd_revalidate_disk(struct gendisk *disk)
2355 {
2356         struct scsi_disk *sdkp = scsi_disk(disk);
2357         struct scsi_device *sdp = sdkp->device;
2358         unsigned char *buffer;
2359         unsigned flush = 0;
2360
2361         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
2362                                       "sd_revalidate_disk\n"));
2363
2364         /*
2365          * If the device is offline, don't try and read capacity or any
2366          * of the other niceties.
2367          */
2368         if (!scsi_device_online(sdp))
2369                 goto out;
2370
2371         buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
2372         if (!buffer) {
2373                 sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
2374                           "allocation failure.\n");
2375                 goto out;
2376         }
2377
2378         sd_spinup_disk(sdkp);
2379
2380         /*
2381          * Without media there is no reason to ask; moreover, some devices
2382          * react badly if we do.
2383          */
2384         if (sdkp->media_present) {
2385                 sd_read_capacity(sdkp, buffer);
2386
2387                 if (sd_try_extended_inquiry(sdp)) {
2388                         sd_read_block_provisioning(sdkp);
2389                         sd_read_block_limits(sdkp);
2390                         sd_read_block_characteristics(sdkp);
2391                 }
2392
2393                 sd_read_write_protect_flag(sdkp, buffer);
2394                 sd_read_cache_type(sdkp, buffer);
2395                 sd_read_app_tag_own(sdkp, buffer);
2396         }
2397
2398         sdkp->first_scan = 0;
2399
2400         /*
2401          * We now have all cache related info, determine how we deal
2402          * with flush requests.
2403          */
2404         if (sdkp->WCE) {
2405                 flush |= REQ_FLUSH;
2406                 if (sdkp->DPOFUA)
2407                         flush |= REQ_FUA;
2408         }
2409
2410         blk_queue_flush(sdkp->disk->queue, flush);
2411
2412         set_capacity(disk, sdkp->capacity);
2413         kfree(buffer);
2414
2415  out:
2416         return 0;
2417 }
2418
2419 /**
2420  *      sd_unlock_native_capacity - unlock native capacity
2421  *      @disk: struct gendisk to set capacity for
2422  *
2423  *      Block layer calls this function if it detects that partitions
2424  *      on @disk reach beyond the end of the device.  If the SCSI host
2425  *      implements ->unlock_native_capacity() method, it's invoked to
2426  *      give it a chance to adjust the device capacity.
2427  *
2428  *      CONTEXT:
2429  *      Defined by block layer.  Might sleep.
2430  */
2431 static void sd_unlock_native_capacity(struct gendisk *disk)
2432 {
2433         struct scsi_device *sdev = scsi_disk(disk)->device;
2434
2435         if (sdev->host->hostt->unlock_native_capacity)
2436                 sdev->host->hostt->unlock_native_capacity(sdev);
2437 }
2438
2439 /**
2440  *      sd_format_disk_name - format disk name
2441  *      @prefix: name prefix - ie. "sd" for SCSI disks
2442  *      @index: index of the disk to format name for
2443  *      @buf: output buffer
2444  *      @buflen: length of the output buffer
2445  *
2446  *      SCSI disk names starts at sda.  The 26th device is sdz and the
2447  *      27th is sdaa.  The last one for two lettered suffix is sdzz
2448  *      which is followed by sdaaa.
2449  *
2450  *      This is basically 26 base counting with one extra 'nil' entry
2451  *      at the beginning from the second digit on and can be
2452  *      determined using similar method as 26 base conversion with the
2453  *      index shifted -1 after each digit is computed.
2454  *
2455  *      CONTEXT:
2456  *      Don't care.
2457  *
2458  *      RETURNS:
2459  *      0 on success, -errno on failure.
2460  */
2461 static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
2462 {
2463         const int base = 'z' - 'a' + 1;
2464         char *begin = buf + strlen(prefix);
2465         char *end = buf + buflen;
2466         char *p;
2467         int unit;
2468
2469         p = end - 1;
2470         *p = '\0';
2471         unit = base;
2472         do {
2473                 if (p == begin)
2474                         return -EINVAL;
2475                 *--p = 'a' + (index % unit);
2476                 index = (index / unit) - 1;
2477         } while (index >= 0);
2478
2479         memmove(begin, p, end - p);
2480         memcpy(buf, prefix, strlen(prefix));
2481
2482         return 0;
2483 }
2484
2485 /*
2486  * The asynchronous part of sd_probe
2487  */
2488 static void sd_probe_async(void *data, async_cookie_t cookie)
2489 {
2490         struct scsi_disk *sdkp = data;
2491         struct scsi_device *sdp;
2492         struct gendisk *gd;
2493         u32 index;
2494         struct device *dev;
2495
2496         sdp = sdkp->device;
2497         gd = sdkp->disk;
2498         index = sdkp->index;
2499         dev = &sdp->sdev_gendev;
2500
2501         gd->major = sd_major((index & 0xf0) >> 4);
2502         gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
2503         gd->minors = SD_MINORS;
2504
2505         gd->fops = &sd_fops;
2506         gd->private_data = &sdkp->driver;
2507         gd->queue = sdkp->device->request_queue;
2508
2509         /* defaults, until the device tells us otherwise */
2510         sdp->sector_size = 512;
2511         sdkp->capacity = 0;
2512         sdkp->media_present = 1;
2513         sdkp->write_prot = 0;
2514         sdkp->WCE = 0;
2515         sdkp->RCD = 0;
2516         sdkp->ATO = 0;
2517         sdkp->first_scan = 1;
2518
2519         sd_revalidate_disk(gd);
2520
2521         blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
2522         blk_queue_unprep_rq(sdp->request_queue, sd_unprep_fn);
2523
2524         gd->driverfs_dev = &sdp->sdev_gendev;
2525         gd->flags = GENHD_FL_EXT_DEVT;
2526         if (sdp->removable) {
2527                 gd->flags |= GENHD_FL_REMOVABLE;
2528                 gd->events |= DISK_EVENT_MEDIA_CHANGE;
2529         }
2530
2531         add_disk(gd);
2532         sd_dif_config_host(sdkp);
2533
2534         sd_revalidate_disk(gd);
2535
2536         sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
2537                   sdp->removable ? "removable " : "");
2538         scsi_autopm_put_device(sdp);
2539         put_device(&sdkp->dev);
2540 }
2541
2542 /**
2543  *      sd_probe - called during driver initialization and whenever a
2544  *      new scsi device is attached to the system. It is called once
2545  *      for each scsi device (not just disks) present.
2546  *      @dev: pointer to device object
2547  *
2548  *      Returns 0 if successful (or not interested in this scsi device 
2549  *      (e.g. scanner)); 1 when there is an error.
2550  *
2551  *      Note: this function is invoked from the scsi mid-level.
2552  *      This function sets up the mapping between a given 
2553  *      <host,channel,id,lun> (found in sdp) and new device name 
2554  *      (e.g. /dev/sda). More precisely it is the block device major 
2555  *      and minor number that is chosen here.
2556  *
2557  *      Assume sd_attach is not re-entrant (for time being)
2558  *      Also think about sd_attach() and sd_remove() running coincidentally.
2559  **/
2560 static int sd_probe(struct device *dev)
2561 {
2562         struct scsi_device *sdp = to_scsi_device(dev);
2563         struct scsi_disk *sdkp;
2564         struct gendisk *gd;
2565         int index;
2566         int error;
2567
2568         error = -ENODEV;
2569         if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
2570                 goto out;
2571
2572         SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
2573                                         "sd_attach\n"));
2574
2575         error = -ENOMEM;
2576         sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
2577         if (!sdkp)
2578                 goto out;
2579
2580         gd = alloc_disk(SD_MINORS);
2581         if (!gd)
2582                 goto out_free;
2583
2584         do {
2585                 if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
2586                         goto out_put;
2587
2588                 spin_lock(&sd_index_lock);
2589                 error = ida_get_new(&sd_index_ida, &index);
2590                 spin_unlock(&sd_index_lock);
2591         } while (error == -EAGAIN);
2592
2593         if (error)
2594                 goto out_put;
2595
2596         if (index >= SD_MAX_DISKS) {
2597                 error = -ENODEV;
2598                 sdev_printk(KERN_WARNING, sdp, "SCSI disk (sd) name space exhausted.\n");
2599                 goto out_free_index;
2600         }
2601
2602         error = sd_format_disk_name("sd", index, gd->disk_name, DISK_NAME_LEN);
2603         if (error)
2604                 goto out_free_index;
2605
2606         sdkp->device = sdp;
2607         sdkp->driver = &sd_template;
2608         sdkp->disk = gd;
2609         sdkp->index = index;
2610         atomic_set(&sdkp->openers, 0);
2611
2612         if (!sdp->request_queue->rq_timeout) {
2613                 if (sdp->type != TYPE_MOD)
2614                         blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
2615                 else
2616                         blk_queue_rq_timeout(sdp->request_queue,
2617                                              SD_MOD_TIMEOUT);
2618         }
2619
2620         device_initialize(&sdkp->dev);
2621         sdkp->dev.parent = dev;
2622         sdkp->dev.class = &sd_disk_class;
2623         dev_set_name(&sdkp->dev, dev_name(dev));
2624
2625         if (device_add(&sdkp->dev))
2626                 goto out_free_index;
2627
2628         get_device(dev);
2629         dev_set_drvdata(dev, sdkp);
2630
2631         get_device(&sdkp->dev); /* prevent release before async_schedule */
2632         async_schedule(sd_probe_async, sdkp);
2633
2634         return 0;
2635
2636  out_free_index:
2637         spin_lock(&sd_index_lock);
2638         ida_remove(&sd_index_ida, index);
2639         spin_unlock(&sd_index_lock);
2640  out_put:
2641         put_disk(gd);
2642  out_free:
2643         kfree(sdkp);
2644  out:
2645         return error;
2646 }
2647
2648 /**
2649  *      sd_remove - called whenever a scsi disk (previously recognized by
2650  *      sd_probe) is detached from the system. It is called (potentially
2651  *      multiple times) during sd module unload.
2652  *      @sdp: pointer to mid level scsi device object
2653  *
2654  *      Note: this function is invoked from the scsi mid-level.
2655  *      This function potentially frees up a device name (e.g. /dev/sdc)
2656  *      that could be re-used by a subsequent sd_probe().
2657  *      This function is not called when the built-in sd driver is "exit-ed".
2658  **/
2659 static int sd_remove(struct device *dev)
2660 {
2661         struct scsi_disk *sdkp;
2662
2663         sdkp = dev_get_drvdata(dev);
2664         scsi_autopm_get_device(sdkp->device);
2665
2666         async_synchronize_full();
2667         blk_queue_prep_rq(sdkp->device->request_queue, scsi_prep_fn);
2668         blk_queue_unprep_rq(sdkp->device->request_queue, NULL);
2669         device_del(&sdkp->dev);
2670         del_gendisk(sdkp->disk);
2671         sd_shutdown(dev);
2672
2673         mutex_lock(&sd_ref_mutex);
2674         dev_set_drvdata(dev, NULL);
2675         put_device(&sdkp->dev);
2676         mutex_unlock(&sd_ref_mutex);
2677
2678         return 0;
2679 }
2680
2681 /**
2682  *      scsi_disk_release - Called to free the scsi_disk structure
2683  *      @dev: pointer to embedded class device
2684  *
2685  *      sd_ref_mutex must be held entering this routine.  Because it is
2686  *      called on last put, you should always use the scsi_disk_get()
2687  *      scsi_disk_put() helpers which manipulate the semaphore directly
2688  *      and never do a direct put_device.
2689  **/
2690 static void scsi_disk_release(struct device *dev)
2691 {
2692         struct scsi_disk *sdkp = to_scsi_disk(dev);
2693         struct gendisk *disk = sdkp->disk;
2694         
2695         spin_lock(&sd_index_lock);
2696         ida_remove(&sd_index_ida, sdkp->index);
2697         spin_unlock(&sd_index_lock);
2698
2699         disk->private_data = NULL;
2700         put_disk(disk);
2701         put_device(&sdkp->device->sdev_gendev);
2702
2703         kfree(sdkp);
2704 }
2705
2706 static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
2707 {
2708         unsigned char cmd[6] = { START_STOP };  /* START_VALID */
2709         struct scsi_sense_hdr sshdr;
2710         struct scsi_device *sdp = sdkp->device;
2711         int res;
2712
2713         if (start)
2714                 cmd[4] |= 1;    /* START */
2715
2716         if (sdp->start_stop_pwr_cond)
2717                 cmd[4] |= start ? 1 << 4 : 3 << 4;      /* Active or Standby */
2718
2719         if (!scsi_device_online(sdp))
2720                 return -ENODEV;
2721
2722         res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
2723                                SD_TIMEOUT, SD_MAX_RETRIES, NULL);
2724         if (res) {
2725                 sd_printk(KERN_WARNING, sdkp, "START_STOP FAILED\n");
2726                 sd_print_result(sdkp, res);
2727                 if (driver_byte(res) & DRIVER_SENSE)
2728                         sd_print_sense_hdr(sdkp, &sshdr);
2729         }
2730
2731         return res;
2732 }
2733
2734 /*
2735  * Send a SYNCHRONIZE CACHE instruction down to the device through
2736  * the normal SCSI command structure.  Wait for the command to
2737  * complete.
2738  */
2739 static void sd_shutdown(struct device *dev)
2740 {
2741         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2742
2743         if (!sdkp)
2744                 return;         /* this can happen */
2745
2746         if (sdkp->WCE) {
2747                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
2748                 sd_sync_cache(sdkp);
2749         }
2750
2751         if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
2752                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
2753                 sd_start_stop_device(sdkp, 0);
2754         }
2755
2756         scsi_disk_put(sdkp);
2757 }
2758
2759 static int sd_suspend(struct device *dev, pm_message_t mesg)
2760 {
2761         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2762         int ret = 0;
2763
2764         if (!sdkp)
2765                 return 0;       /* this can happen */
2766
2767         if (sdkp->WCE) {
2768                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
2769                 ret = sd_sync_cache(sdkp);
2770                 if (ret)
2771                         goto done;
2772         }
2773
2774         if ((mesg.event & PM_EVENT_SLEEP) && sdkp->device->manage_start_stop) {
2775                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
2776                 ret = sd_start_stop_device(sdkp, 0);
2777         }
2778
2779 done:
2780         scsi_disk_put(sdkp);
2781         return ret;
2782 }
2783
2784 static int sd_resume(struct device *dev)
2785 {
2786         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2787         int ret = 0;
2788
2789         if (!sdkp->device->manage_start_stop)
2790                 goto done;
2791
2792         sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
2793         ret = sd_start_stop_device(sdkp, 1);
2794
2795 done:
2796         scsi_disk_put(sdkp);
2797         return ret;
2798 }
2799
2800 /**
2801  *      init_sd - entry point for this driver (both when built in or when
2802  *      a module).
2803  *
2804  *      Note: this function registers this driver with the scsi mid-level.
2805  **/
2806 static int __init init_sd(void)
2807 {
2808         int majors = 0, i, err;
2809
2810         SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
2811
2812         for (i = 0; i < SD_MAJORS; i++)
2813                 if (register_blkdev(sd_major(i), "sd") == 0)
2814                         majors++;
2815
2816         if (!majors)
2817                 return -ENODEV;
2818
2819         err = class_register(&sd_disk_class);
2820         if (err)
2821                 goto err_out;
2822
2823         err = scsi_register_driver(&sd_template.gendrv);
2824         if (err)
2825                 goto err_out_class;
2826
2827         sd_cdb_cache = kmem_cache_create("sd_ext_cdb", SD_EXT_CDB_SIZE,
2828                                          0, 0, NULL);
2829         if (!sd_cdb_cache) {
2830                 printk(KERN_ERR "sd: can't init extended cdb cache\n");
2831                 goto err_out_class;
2832         }
2833
2834         sd_cdb_pool = mempool_create_slab_pool(SD_MEMPOOL_SIZE, sd_cdb_cache);
2835         if (!sd_cdb_pool) {
2836                 printk(KERN_ERR "sd: can't init extended cdb pool\n");
2837                 goto err_out_cache;
2838         }
2839
2840         return 0;
2841
2842 err_out_cache:
2843         kmem_cache_destroy(sd_cdb_cache);
2844
2845 err_out_class:
2846         class_unregister(&sd_disk_class);
2847 err_out:
2848         for (i = 0; i < SD_MAJORS; i++)
2849                 unregister_blkdev(sd_major(i), "sd");
2850         return err;
2851 }
2852
2853 /**
2854  *      exit_sd - exit point for this driver (when it is a module).
2855  *
2856  *      Note: this function unregisters this driver from the scsi mid-level.
2857  **/
2858 static void __exit exit_sd(void)
2859 {
2860         int i;
2861
2862         SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
2863
2864         mempool_destroy(sd_cdb_pool);
2865         kmem_cache_destroy(sd_cdb_cache);
2866
2867         scsi_unregister_driver(&sd_template.gendrv);
2868         class_unregister(&sd_disk_class);
2869
2870         for (i = 0; i < SD_MAJORS; i++)
2871                 unregister_blkdev(sd_major(i), "sd");
2872 }
2873
2874 module_init(init_sd);
2875 module_exit(exit_sd);
2876
2877 static void sd_print_sense_hdr(struct scsi_disk *sdkp,
2878                                struct scsi_sense_hdr *sshdr)
2879 {
2880         sd_printk(KERN_INFO, sdkp, " ");
2881         scsi_show_sense_hdr(sshdr);
2882         sd_printk(KERN_INFO, sdkp, " ");
2883         scsi_show_extd_sense(sshdr->asc, sshdr->ascq);
2884 }
2885
2886 static void sd_print_result(struct scsi_disk *sdkp, int result)
2887 {
2888         sd_printk(KERN_INFO, sdkp, " ");
2889         scsi_show_result(result);
2890 }
2891