Merge branch 'wire-accept4' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl...
[cascardo/linux.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 <linux/pm_runtime.h>
54 #include <asm/uaccess.h>
55 #include <asm/unaligned.h>
56
57 #include <scsi/scsi.h>
58 #include <scsi/scsi_cmnd.h>
59 #include <scsi/scsi_dbg.h>
60 #include <scsi/scsi_device.h>
61 #include <scsi/scsi_driver.h>
62 #include <scsi/scsi_eh.h>
63 #include <scsi/scsi_host.h>
64 #include <scsi/scsi_ioctl.h>
65 #include <scsi/scsicam.h>
66
67 #include "sd.h"
68 #include "scsi_logging.h"
69
70 MODULE_AUTHOR("Eric Youngdale");
71 MODULE_DESCRIPTION("SCSI disk (sd) driver");
72 MODULE_LICENSE("GPL");
73
74 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
75 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
76 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
77 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
78 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
79 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
80 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
81 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
82 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
83 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
84 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
85 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
86 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
87 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
88 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
89 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
90 MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
91 MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
92 MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
93
94 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
95 #define SD_MINORS       16
96 #else
97 #define SD_MINORS       0
98 #endif
99
100 static void sd_config_discard(struct scsi_disk *, unsigned int);
101 static int  sd_revalidate_disk(struct gendisk *);
102 static void sd_unlock_native_capacity(struct gendisk *disk);
103 static int  sd_probe(struct device *);
104 static int  sd_remove(struct device *);
105 static void sd_shutdown(struct device *);
106 static int sd_suspend(struct device *, pm_message_t state);
107 static int sd_resume(struct device *);
108 static void sd_rescan(struct device *);
109 static int sd_done(struct scsi_cmnd *);
110 static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
111 static void scsi_disk_release(struct device *cdev);
112 static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);
113 static void sd_print_result(struct scsi_disk *, int);
114
115 static DEFINE_SPINLOCK(sd_index_lock);
116 static DEFINE_IDA(sd_index_ida);
117
118 /* This semaphore is used to mediate the 0->1 reference get in the
119  * face of object destruction (i.e. we can't allow a get on an
120  * object after last put) */
121 static DEFINE_MUTEX(sd_ref_mutex);
122
123 static struct kmem_cache *sd_cdb_cache;
124 static mempool_t *sd_cdb_pool;
125
126 static const char *sd_cache_types[] = {
127         "write through", "none", "write back",
128         "write back, no read (daft)"
129 };
130
131 static ssize_t
132 sd_store_cache_type(struct device *dev, struct device_attribute *attr,
133                     const char *buf, size_t count)
134 {
135         int i, ct = -1, rcd, wce, sp;
136         struct scsi_disk *sdkp = to_scsi_disk(dev);
137         struct scsi_device *sdp = sdkp->device;
138         char buffer[64];
139         char *buffer_data;
140         struct scsi_mode_data data;
141         struct scsi_sense_hdr sshdr;
142         int len;
143
144         if (sdp->type != TYPE_DISK)
145                 /* no cache control on RBC devices; theoretically they
146                  * can do it, but there's probably so many exceptions
147                  * it's not worth the risk */
148                 return -EINVAL;
149
150         for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
151                 len = strlen(sd_cache_types[i]);
152                 if (strncmp(sd_cache_types[i], buf, len) == 0 &&
153                     buf[len] == '\n') {
154                         ct = i;
155                         break;
156                 }
157         }
158         if (ct < 0)
159                 return -EINVAL;
160         rcd = ct & 0x01 ? 1 : 0;
161         wce = ct & 0x02 ? 1 : 0;
162         if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
163                             SD_MAX_RETRIES, &data, NULL))
164                 return -EINVAL;
165         len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
166                   data.block_descriptor_length);
167         buffer_data = buffer + data.header_length +
168                 data.block_descriptor_length;
169         buffer_data[2] &= ~0x05;
170         buffer_data[2] |= wce << 2 | rcd;
171         sp = buffer_data[0] & 0x80 ? 1 : 0;
172
173         if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
174                              SD_MAX_RETRIES, &data, &sshdr)) {
175                 if (scsi_sense_valid(&sshdr))
176                         sd_print_sense_hdr(sdkp, &sshdr);
177                 return -EINVAL;
178         }
179         revalidate_disk(sdkp->disk);
180         return count;
181 }
182
183 static ssize_t
184 sd_store_manage_start_stop(struct device *dev, struct device_attribute *attr,
185                            const char *buf, size_t count)
186 {
187         struct scsi_disk *sdkp = to_scsi_disk(dev);
188         struct scsi_device *sdp = sdkp->device;
189
190         if (!capable(CAP_SYS_ADMIN))
191                 return -EACCES;
192
193         sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);
194
195         return count;
196 }
197
198 static ssize_t
199 sd_store_allow_restart(struct device *dev, struct device_attribute *attr,
200                        const char *buf, size_t count)
201 {
202         struct scsi_disk *sdkp = to_scsi_disk(dev);
203         struct scsi_device *sdp = sdkp->device;
204
205         if (!capable(CAP_SYS_ADMIN))
206                 return -EACCES;
207
208         if (sdp->type != TYPE_DISK)
209                 return -EINVAL;
210
211         sdp->allow_restart = simple_strtoul(buf, NULL, 10);
212
213         return count;
214 }
215
216 static ssize_t
217 sd_show_cache_type(struct device *dev, struct device_attribute *attr,
218                    char *buf)
219 {
220         struct scsi_disk *sdkp = to_scsi_disk(dev);
221         int ct = sdkp->RCD + 2*sdkp->WCE;
222
223         return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
224 }
225
226 static ssize_t
227 sd_show_fua(struct device *dev, struct device_attribute *attr, char *buf)
228 {
229         struct scsi_disk *sdkp = to_scsi_disk(dev);
230
231         return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
232 }
233
234 static ssize_t
235 sd_show_manage_start_stop(struct device *dev, struct device_attribute *attr,
236                           char *buf)
237 {
238         struct scsi_disk *sdkp = to_scsi_disk(dev);
239         struct scsi_device *sdp = sdkp->device;
240
241         return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
242 }
243
244 static ssize_t
245 sd_show_allow_restart(struct device *dev, struct device_attribute *attr,
246                       char *buf)
247 {
248         struct scsi_disk *sdkp = to_scsi_disk(dev);
249
250         return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
251 }
252
253 static ssize_t
254 sd_show_protection_type(struct device *dev, struct device_attribute *attr,
255                         char *buf)
256 {
257         struct scsi_disk *sdkp = to_scsi_disk(dev);
258
259         return snprintf(buf, 20, "%u\n", sdkp->protection_type);
260 }
261
262 static ssize_t
263 sd_show_protection_mode(struct device *dev, struct device_attribute *attr,
264                         char *buf)
265 {
266         struct scsi_disk *sdkp = to_scsi_disk(dev);
267         struct scsi_device *sdp = sdkp->device;
268         unsigned int dif, dix;
269
270         dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
271         dix = scsi_host_dix_capable(sdp->host, sdkp->protection_type);
272
273         if (!dix && scsi_host_dix_capable(sdp->host, SD_DIF_TYPE0_PROTECTION)) {
274                 dif = 0;
275                 dix = 1;
276         }
277
278         if (!dif && !dix)
279                 return snprintf(buf, 20, "none\n");
280
281         return snprintf(buf, 20, "%s%u\n", dix ? "dix" : "dif", dif);
282 }
283
284 static ssize_t
285 sd_show_app_tag_own(struct device *dev, struct device_attribute *attr,
286                     char *buf)
287 {
288         struct scsi_disk *sdkp = to_scsi_disk(dev);
289
290         return snprintf(buf, 20, "%u\n", sdkp->ATO);
291 }
292
293 static ssize_t
294 sd_show_thin_provisioning(struct device *dev, struct device_attribute *attr,
295                           char *buf)
296 {
297         struct scsi_disk *sdkp = to_scsi_disk(dev);
298
299         return snprintf(buf, 20, "%u\n", sdkp->lbpme);
300 }
301
302 static const char *lbp_mode[] = {
303         [SD_LBP_FULL]           = "full",
304         [SD_LBP_UNMAP]          = "unmap",
305         [SD_LBP_WS16]           = "writesame_16",
306         [SD_LBP_WS10]           = "writesame_10",
307         [SD_LBP_ZERO]           = "writesame_zero",
308         [SD_LBP_DISABLE]        = "disabled",
309 };
310
311 static ssize_t
312 sd_show_provisioning_mode(struct device *dev, struct device_attribute *attr,
313                           char *buf)
314 {
315         struct scsi_disk *sdkp = to_scsi_disk(dev);
316
317         return snprintf(buf, 20, "%s\n", lbp_mode[sdkp->provisioning_mode]);
318 }
319
320 static ssize_t
321 sd_store_provisioning_mode(struct device *dev, struct device_attribute *attr,
322                            const char *buf, size_t count)
323 {
324         struct scsi_disk *sdkp = to_scsi_disk(dev);
325         struct scsi_device *sdp = sdkp->device;
326
327         if (!capable(CAP_SYS_ADMIN))
328                 return -EACCES;
329
330         if (sdp->type != TYPE_DISK)
331                 return -EINVAL;
332
333         if (!strncmp(buf, lbp_mode[SD_LBP_UNMAP], 20))
334                 sd_config_discard(sdkp, SD_LBP_UNMAP);
335         else if (!strncmp(buf, lbp_mode[SD_LBP_WS16], 20))
336                 sd_config_discard(sdkp, SD_LBP_WS16);
337         else if (!strncmp(buf, lbp_mode[SD_LBP_WS10], 20))
338                 sd_config_discard(sdkp, SD_LBP_WS10);
339         else if (!strncmp(buf, lbp_mode[SD_LBP_ZERO], 20))
340                 sd_config_discard(sdkp, SD_LBP_ZERO);
341         else if (!strncmp(buf, lbp_mode[SD_LBP_DISABLE], 20))
342                 sd_config_discard(sdkp, SD_LBP_DISABLE);
343         else
344                 return -EINVAL;
345
346         return count;
347 }
348
349 static struct device_attribute sd_disk_attrs[] = {
350         __ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
351                sd_store_cache_type),
352         __ATTR(FUA, S_IRUGO, sd_show_fua, NULL),
353         __ATTR(allow_restart, S_IRUGO|S_IWUSR, sd_show_allow_restart,
354                sd_store_allow_restart),
355         __ATTR(manage_start_stop, S_IRUGO|S_IWUSR, sd_show_manage_start_stop,
356                sd_store_manage_start_stop),
357         __ATTR(protection_type, S_IRUGO, sd_show_protection_type, NULL),
358         __ATTR(protection_mode, S_IRUGO, sd_show_protection_mode, NULL),
359         __ATTR(app_tag_own, S_IRUGO, sd_show_app_tag_own, NULL),
360         __ATTR(thin_provisioning, S_IRUGO, sd_show_thin_provisioning, NULL),
361         __ATTR(provisioning_mode, S_IRUGO|S_IWUSR, sd_show_provisioning_mode,
362                sd_store_provisioning_mode),
363         __ATTR_NULL,
364 };
365
366 static struct class sd_disk_class = {
367         .name           = "scsi_disk",
368         .owner          = THIS_MODULE,
369         .dev_release    = scsi_disk_release,
370         .dev_attrs      = sd_disk_attrs,
371 };
372
373 static struct scsi_driver sd_template = {
374         .owner                  = THIS_MODULE,
375         .gendrv = {
376                 .name           = "sd",
377                 .probe          = sd_probe,
378                 .remove         = sd_remove,
379                 .suspend        = sd_suspend,
380                 .resume         = sd_resume,
381                 .shutdown       = sd_shutdown,
382         },
383         .rescan                 = sd_rescan,
384         .done                   = sd_done,
385 };
386
387 /*
388  * Device no to disk mapping:
389  * 
390  *       major         disc2     disc  p1
391  *   |............|.............|....|....| <- dev_t
392  *    31        20 19          8 7  4 3  0
393  * 
394  * Inside a major, we have 16k disks, however mapped non-
395  * contiguously. The first 16 disks are for major0, the next
396  * ones with major1, ... Disk 256 is for major0 again, disk 272 
397  * for major1, ... 
398  * As we stay compatible with our numbering scheme, we can reuse 
399  * the well-know SCSI majors 8, 65--71, 136--143.
400  */
401 static int sd_major(int major_idx)
402 {
403         switch (major_idx) {
404         case 0:
405                 return SCSI_DISK0_MAJOR;
406         case 1 ... 7:
407                 return SCSI_DISK1_MAJOR + major_idx - 1;
408         case 8 ... 15:
409                 return SCSI_DISK8_MAJOR + major_idx - 8;
410         default:
411                 BUG();
412                 return 0;       /* shut up gcc */
413         }
414 }
415
416 static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
417 {
418         struct scsi_disk *sdkp = NULL;
419
420         if (disk->private_data) {
421                 sdkp = scsi_disk(disk);
422                 if (scsi_device_get(sdkp->device) == 0)
423                         get_device(&sdkp->dev);
424                 else
425                         sdkp = NULL;
426         }
427         return sdkp;
428 }
429
430 static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
431 {
432         struct scsi_disk *sdkp;
433
434         mutex_lock(&sd_ref_mutex);
435         sdkp = __scsi_disk_get(disk);
436         mutex_unlock(&sd_ref_mutex);
437         return sdkp;
438 }
439
440 static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev)
441 {
442         struct scsi_disk *sdkp;
443
444         mutex_lock(&sd_ref_mutex);
445         sdkp = dev_get_drvdata(dev);
446         if (sdkp)
447                 sdkp = __scsi_disk_get(sdkp->disk);
448         mutex_unlock(&sd_ref_mutex);
449         return sdkp;
450 }
451
452 static void scsi_disk_put(struct scsi_disk *sdkp)
453 {
454         struct scsi_device *sdev = sdkp->device;
455
456         mutex_lock(&sd_ref_mutex);
457         put_device(&sdkp->dev);
458         scsi_device_put(sdev);
459         mutex_unlock(&sd_ref_mutex);
460 }
461
462 static void sd_prot_op(struct scsi_cmnd *scmd, unsigned int dif)
463 {
464         unsigned int prot_op = SCSI_PROT_NORMAL;
465         unsigned int dix = scsi_prot_sg_count(scmd);
466
467         if (scmd->sc_data_direction == DMA_FROM_DEVICE) {
468                 if (dif && dix)
469                         prot_op = SCSI_PROT_READ_PASS;
470                 else if (dif && !dix)
471                         prot_op = SCSI_PROT_READ_STRIP;
472                 else if (!dif && dix)
473                         prot_op = SCSI_PROT_READ_INSERT;
474         } else {
475                 if (dif && dix)
476                         prot_op = SCSI_PROT_WRITE_PASS;
477                 else if (dif && !dix)
478                         prot_op = SCSI_PROT_WRITE_INSERT;
479                 else if (!dif && dix)
480                         prot_op = SCSI_PROT_WRITE_STRIP;
481         }
482
483         scsi_set_prot_op(scmd, prot_op);
484         scsi_set_prot_type(scmd, dif);
485 }
486
487 static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
488 {
489         struct request_queue *q = sdkp->disk->queue;
490         unsigned int logical_block_size = sdkp->device->sector_size;
491         unsigned int max_blocks = 0;
492
493         q->limits.discard_zeroes_data = sdkp->lbprz;
494         q->limits.discard_alignment = sdkp->unmap_alignment *
495                 logical_block_size;
496         q->limits.discard_granularity =
497                 max(sdkp->physical_block_size,
498                     sdkp->unmap_granularity * logical_block_size);
499
500         switch (mode) {
501
502         case SD_LBP_DISABLE:
503                 q->limits.max_discard_sectors = 0;
504                 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
505                 return;
506
507         case SD_LBP_UNMAP:
508                 max_blocks = min_not_zero(sdkp->max_unmap_blocks, 0xffffffff);
509                 break;
510
511         case SD_LBP_WS16:
512                 max_blocks = min_not_zero(sdkp->max_ws_blocks, 0xffffffff);
513                 break;
514
515         case SD_LBP_WS10:
516                 max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
517                 break;
518
519         case SD_LBP_ZERO:
520                 max_blocks = min_not_zero(sdkp->max_ws_blocks, (u32)0xffff);
521                 q->limits.discard_zeroes_data = 1;
522                 break;
523         }
524
525         q->limits.max_discard_sectors = max_blocks * (logical_block_size >> 9);
526         queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
527
528         sdkp->provisioning_mode = mode;
529 }
530
531 /**
532  * scsi_setup_discard_cmnd - unmap blocks on thinly provisioned device
533  * @sdp: scsi device to operate one
534  * @rq: Request to prepare
535  *
536  * Will issue either UNMAP or WRITE SAME(16) depending on preference
537  * indicated by target device.
538  **/
539 static int scsi_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
540 {
541         struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
542         struct bio *bio = rq->bio;
543         sector_t sector = bio->bi_sector;
544         unsigned int nr_sectors = bio_sectors(bio);
545         unsigned int len;
546         int ret;
547         char *buf;
548         struct page *page;
549
550         if (sdkp->device->sector_size == 4096) {
551                 sector >>= 3;
552                 nr_sectors >>= 3;
553         }
554
555         rq->timeout = SD_TIMEOUT;
556
557         memset(rq->cmd, 0, rq->cmd_len);
558
559         page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
560         if (!page)
561                 return BLKPREP_DEFER;
562
563         switch (sdkp->provisioning_mode) {
564         case SD_LBP_UNMAP:
565                 buf = page_address(page);
566
567                 rq->cmd_len = 10;
568                 rq->cmd[0] = UNMAP;
569                 rq->cmd[8] = 24;
570
571                 put_unaligned_be16(6 + 16, &buf[0]);
572                 put_unaligned_be16(16, &buf[2]);
573                 put_unaligned_be64(sector, &buf[8]);
574                 put_unaligned_be32(nr_sectors, &buf[16]);
575
576                 len = 24;
577                 break;
578
579         case SD_LBP_WS16:
580                 rq->cmd_len = 16;
581                 rq->cmd[0] = WRITE_SAME_16;
582                 rq->cmd[1] = 0x8; /* UNMAP */
583                 put_unaligned_be64(sector, &rq->cmd[2]);
584                 put_unaligned_be32(nr_sectors, &rq->cmd[10]);
585
586                 len = sdkp->device->sector_size;
587                 break;
588
589         case SD_LBP_WS10:
590         case SD_LBP_ZERO:
591                 rq->cmd_len = 10;
592                 rq->cmd[0] = WRITE_SAME;
593                 if (sdkp->provisioning_mode == SD_LBP_WS10)
594                         rq->cmd[1] = 0x8; /* UNMAP */
595                 put_unaligned_be32(sector, &rq->cmd[2]);
596                 put_unaligned_be16(nr_sectors, &rq->cmd[7]);
597
598                 len = sdkp->device->sector_size;
599                 break;
600
601         default:
602                 ret = BLKPREP_KILL;
603                 goto out;
604         }
605
606         blk_add_request_payload(rq, page, len);
607         ret = scsi_setup_blk_pc_cmnd(sdp, rq);
608         rq->buffer = page_address(page);
609
610 out:
611         if (ret != BLKPREP_OK) {
612                 __free_page(page);
613                 rq->buffer = NULL;
614         }
615         return ret;
616 }
617
618 static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq)
619 {
620         rq->timeout = SD_FLUSH_TIMEOUT;
621         rq->retries = SD_MAX_RETRIES;
622         rq->cmd[0] = SYNCHRONIZE_CACHE;
623         rq->cmd_len = 10;
624
625         return scsi_setup_blk_pc_cmnd(sdp, rq);
626 }
627
628 static void sd_unprep_fn(struct request_queue *q, struct request *rq)
629 {
630         if (rq->cmd_flags & REQ_DISCARD) {
631                 free_page((unsigned long)rq->buffer);
632                 rq->buffer = NULL;
633         }
634 }
635
636 /**
637  *      sd_init_command - build a scsi (read or write) command from
638  *      information in the request structure.
639  *      @SCpnt: pointer to mid-level's per scsi command structure that
640  *      contains request and into which the scsi command is written
641  *
642  *      Returns 1 if successful and 0 if error (or cannot be done now).
643  **/
644 static int sd_prep_fn(struct request_queue *q, struct request *rq)
645 {
646         struct scsi_cmnd *SCpnt;
647         struct scsi_device *sdp = q->queuedata;
648         struct gendisk *disk = rq->rq_disk;
649         struct scsi_disk *sdkp;
650         sector_t block = blk_rq_pos(rq);
651         sector_t threshold;
652         unsigned int this_count = blk_rq_sectors(rq);
653         int ret, host_dif;
654         unsigned char protect;
655
656         /*
657          * Discard request come in as REQ_TYPE_FS but we turn them into
658          * block PC requests to make life easier.
659          */
660         if (rq->cmd_flags & REQ_DISCARD) {
661                 ret = scsi_setup_discard_cmnd(sdp, rq);
662                 goto out;
663         } else if (rq->cmd_flags & REQ_FLUSH) {
664                 ret = scsi_setup_flush_cmnd(sdp, rq);
665                 goto out;
666         } else if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
667                 ret = scsi_setup_blk_pc_cmnd(sdp, rq);
668                 goto out;
669         } else if (rq->cmd_type != REQ_TYPE_FS) {
670                 ret = BLKPREP_KILL;
671                 goto out;
672         }
673         ret = scsi_setup_fs_cmnd(sdp, rq);
674         if (ret != BLKPREP_OK)
675                 goto out;
676         SCpnt = rq->special;
677         sdkp = scsi_disk(disk);
678
679         /* from here on until we're complete, any goto out
680          * is used for a killable error condition */
681         ret = BLKPREP_KILL;
682
683         SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
684                                         "sd_init_command: block=%llu, "
685                                         "count=%d\n",
686                                         (unsigned long long)block,
687                                         this_count));
688
689         if (!sdp || !scsi_device_online(sdp) ||
690             block + blk_rq_sectors(rq) > get_capacity(disk)) {
691                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
692                                                 "Finishing %u sectors\n",
693                                                 blk_rq_sectors(rq)));
694                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
695                                                 "Retry with 0x%p\n", SCpnt));
696                 goto out;
697         }
698
699         if (sdp->changed) {
700                 /*
701                  * quietly refuse to do anything to a changed disc until 
702                  * the changed bit has been reset
703                  */
704                 /* printk("SCSI disk has been changed or is not present. Prohibiting further I/O.\n"); */
705                 goto out;
706         }
707
708         /*
709          * Some SD card readers can't handle multi-sector accesses which touch
710          * the last one or two hardware sectors.  Split accesses as needed.
711          */
712         threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
713                 (sdp->sector_size / 512);
714
715         if (unlikely(sdp->last_sector_bug && block + this_count > threshold)) {
716                 if (block < threshold) {
717                         /* Access up to the threshold but not beyond */
718                         this_count = threshold - block;
719                 } else {
720                         /* Access only a single hardware sector */
721                         this_count = sdp->sector_size / 512;
722                 }
723         }
724
725         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
726                                         (unsigned long long)block));
727
728         /*
729          * If we have a 1K hardware sectorsize, prevent access to single
730          * 512 byte sectors.  In theory we could handle this - in fact
731          * the scsi cdrom driver must be able to handle this because
732          * we typically use 1K blocksizes, and cdroms typically have
733          * 2K hardware sectorsizes.  Of course, things are simpler
734          * with the cdrom, since it is read-only.  For performance
735          * reasons, the filesystems should be able to handle this
736          * and not force the scsi disk driver to use bounce buffers
737          * for this.
738          */
739         if (sdp->sector_size == 1024) {
740                 if ((block & 1) || (blk_rq_sectors(rq) & 1)) {
741                         scmd_printk(KERN_ERR, SCpnt,
742                                     "Bad block number requested\n");
743                         goto out;
744                 } else {
745                         block = block >> 1;
746                         this_count = this_count >> 1;
747                 }
748         }
749         if (sdp->sector_size == 2048) {
750                 if ((block & 3) || (blk_rq_sectors(rq) & 3)) {
751                         scmd_printk(KERN_ERR, SCpnt,
752                                     "Bad block number requested\n");
753                         goto out;
754                 } else {
755                         block = block >> 2;
756                         this_count = this_count >> 2;
757                 }
758         }
759         if (sdp->sector_size == 4096) {
760                 if ((block & 7) || (blk_rq_sectors(rq) & 7)) {
761                         scmd_printk(KERN_ERR, SCpnt,
762                                     "Bad block number requested\n");
763                         goto out;
764                 } else {
765                         block = block >> 3;
766                         this_count = this_count >> 3;
767                 }
768         }
769         if (rq_data_dir(rq) == WRITE) {
770                 if (!sdp->writeable) {
771                         goto out;
772                 }
773                 SCpnt->cmnd[0] = WRITE_6;
774                 SCpnt->sc_data_direction = DMA_TO_DEVICE;
775
776                 if (blk_integrity_rq(rq) &&
777                     sd_dif_prepare(rq, block, sdp->sector_size) == -EIO)
778                         goto out;
779
780         } else if (rq_data_dir(rq) == READ) {
781                 SCpnt->cmnd[0] = READ_6;
782                 SCpnt->sc_data_direction = DMA_FROM_DEVICE;
783         } else {
784                 scmd_printk(KERN_ERR, SCpnt, "Unknown command %x\n", rq->cmd_flags);
785                 goto out;
786         }
787
788         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
789                                         "%s %d/%u 512 byte blocks.\n",
790                                         (rq_data_dir(rq) == WRITE) ?
791                                         "writing" : "reading", this_count,
792                                         blk_rq_sectors(rq)));
793
794         /* Set RDPROTECT/WRPROTECT if disk is formatted with DIF */
795         host_dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
796         if (host_dif)
797                 protect = 1 << 5;
798         else
799                 protect = 0;
800
801         if (host_dif == SD_DIF_TYPE2_PROTECTION) {
802                 SCpnt->cmnd = mempool_alloc(sd_cdb_pool, GFP_ATOMIC);
803
804                 if (unlikely(SCpnt->cmnd == NULL)) {
805                         ret = BLKPREP_DEFER;
806                         goto out;
807                 }
808
809                 SCpnt->cmd_len = SD_EXT_CDB_SIZE;
810                 memset(SCpnt->cmnd, 0, SCpnt->cmd_len);
811                 SCpnt->cmnd[0] = VARIABLE_LENGTH_CMD;
812                 SCpnt->cmnd[7] = 0x18;
813                 SCpnt->cmnd[9] = (rq_data_dir(rq) == READ) ? READ_32 : WRITE_32;
814                 SCpnt->cmnd[10] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
815
816                 /* LBA */
817                 SCpnt->cmnd[12] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
818                 SCpnt->cmnd[13] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
819                 SCpnt->cmnd[14] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
820                 SCpnt->cmnd[15] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
821                 SCpnt->cmnd[16] = (unsigned char) (block >> 24) & 0xff;
822                 SCpnt->cmnd[17] = (unsigned char) (block >> 16) & 0xff;
823                 SCpnt->cmnd[18] = (unsigned char) (block >> 8) & 0xff;
824                 SCpnt->cmnd[19] = (unsigned char) block & 0xff;
825
826                 /* Expected Indirect LBA */
827                 SCpnt->cmnd[20] = (unsigned char) (block >> 24) & 0xff;
828                 SCpnt->cmnd[21] = (unsigned char) (block >> 16) & 0xff;
829                 SCpnt->cmnd[22] = (unsigned char) (block >> 8) & 0xff;
830                 SCpnt->cmnd[23] = (unsigned char) block & 0xff;
831
832                 /* Transfer length */
833                 SCpnt->cmnd[28] = (unsigned char) (this_count >> 24) & 0xff;
834                 SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
835                 SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
836                 SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
837         } else if (block > 0xffffffff) {
838                 SCpnt->cmnd[0] += READ_16 - READ_6;
839                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
840                 SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
841                 SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
842                 SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
843                 SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
844                 SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
845                 SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
846                 SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
847                 SCpnt->cmnd[9] = (unsigned char) block & 0xff;
848                 SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
849                 SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
850                 SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
851                 SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
852                 SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
853         } else if ((this_count > 0xff) || (block > 0x1fffff) ||
854                    scsi_device_protection(SCpnt->device) ||
855                    SCpnt->device->use_10_for_rw) {
856                 if (this_count > 0xffff)
857                         this_count = 0xffff;
858
859                 SCpnt->cmnd[0] += READ_10 - READ_6;
860                 SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
861                 SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
862                 SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
863                 SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
864                 SCpnt->cmnd[5] = (unsigned char) block & 0xff;
865                 SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
866                 SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
867                 SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
868         } else {
869                 if (unlikely(rq->cmd_flags & REQ_FUA)) {
870                         /*
871                          * This happens only if this drive failed
872                          * 10byte rw command with ILLEGAL_REQUEST
873                          * during operation and thus turned off
874                          * use_10_for_rw.
875                          */
876                         scmd_printk(KERN_ERR, SCpnt,
877                                     "FUA write on READ/WRITE(6) drive\n");
878                         goto out;
879                 }
880
881                 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
882                 SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
883                 SCpnt->cmnd[3] = (unsigned char) block & 0xff;
884                 SCpnt->cmnd[4] = (unsigned char) this_count;
885                 SCpnt->cmnd[5] = 0;
886         }
887         SCpnt->sdb.length = this_count * sdp->sector_size;
888
889         /* If DIF or DIX is enabled, tell HBA how to handle request */
890         if (host_dif || scsi_prot_sg_count(SCpnt))
891                 sd_prot_op(SCpnt, host_dif);
892
893         /*
894          * We shouldn't disconnect in the middle of a sector, so with a dumb
895          * host adapter, it's safe to assume that we can at least transfer
896          * this many bytes between each connect / disconnect.
897          */
898         SCpnt->transfersize = sdp->sector_size;
899         SCpnt->underflow = this_count << 9;
900         SCpnt->allowed = SD_MAX_RETRIES;
901
902         /*
903          * This indicates that the command is ready from our end to be
904          * queued.
905          */
906         ret = BLKPREP_OK;
907  out:
908         return scsi_prep_return(q, rq, ret);
909 }
910
911 /**
912  *      sd_open - open a scsi disk device
913  *      @inode: only i_rdev member may be used
914  *      @filp: only f_mode and f_flags may be used
915  *
916  *      Returns 0 if successful. Returns a negated errno value in case 
917  *      of error.
918  *
919  *      Note: This can be called from a user context (e.g. fsck(1) )
920  *      or from within the kernel (e.g. as a result of a mount(1) ).
921  *      In the latter case @inode and @filp carry an abridged amount
922  *      of information as noted above.
923  *
924  *      Locking: called with bdev->bd_mutex held.
925  **/
926 static int sd_open(struct block_device *bdev, fmode_t mode)
927 {
928         struct scsi_disk *sdkp = scsi_disk_get(bdev->bd_disk);
929         struct scsi_device *sdev;
930         int retval;
931
932         if (!sdkp)
933                 return -ENXIO;
934
935         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
936
937         sdev = sdkp->device;
938
939         retval = scsi_autopm_get_device(sdev);
940         if (retval)
941                 goto error_autopm;
942
943         /*
944          * If the device is in error recovery, wait until it is done.
945          * If the device is offline, then disallow any access to it.
946          */
947         retval = -ENXIO;
948         if (!scsi_block_when_processing_errors(sdev))
949                 goto error_out;
950
951         if (sdev->removable || sdkp->write_prot)
952                 check_disk_change(bdev);
953
954         /*
955          * If the drive is empty, just let the open fail.
956          */
957         retval = -ENOMEDIUM;
958         if (sdev->removable && !sdkp->media_present && !(mode & FMODE_NDELAY))
959                 goto error_out;
960
961         /*
962          * If the device has the write protect tab set, have the open fail
963          * if the user expects to be able to write to the thing.
964          */
965         retval = -EROFS;
966         if (sdkp->write_prot && (mode & FMODE_WRITE))
967                 goto error_out;
968
969         /*
970          * It is possible that the disk changing stuff resulted in
971          * the device being taken offline.  If this is the case,
972          * report this to the user, and don't pretend that the
973          * open actually succeeded.
974          */
975         retval = -ENXIO;
976         if (!scsi_device_online(sdev))
977                 goto error_out;
978
979         if ((atomic_inc_return(&sdkp->openers) == 1) && sdev->removable) {
980                 if (scsi_block_when_processing_errors(sdev))
981                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
982         }
983
984         return 0;
985
986 error_out:
987         scsi_autopm_put_device(sdev);
988 error_autopm:
989         scsi_disk_put(sdkp);
990         return retval;  
991 }
992
993 /**
994  *      sd_release - invoked when the (last) close(2) is called on this
995  *      scsi disk.
996  *      @inode: only i_rdev member may be used
997  *      @filp: only f_mode and f_flags may be used
998  *
999  *      Returns 0. 
1000  *
1001  *      Note: may block (uninterruptible) if error recovery is underway
1002  *      on this disk.
1003  *
1004  *      Locking: called with bdev->bd_mutex held.
1005  **/
1006 static int sd_release(struct gendisk *disk, fmode_t mode)
1007 {
1008         struct scsi_disk *sdkp = scsi_disk(disk);
1009         struct scsi_device *sdev = sdkp->device;
1010
1011         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
1012
1013         if (atomic_dec_return(&sdkp->openers) == 0 && sdev->removable) {
1014                 if (scsi_block_when_processing_errors(sdev))
1015                         scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
1016         }
1017
1018         /*
1019          * XXX and what if there are packets in flight and this close()
1020          * XXX is followed by a "rmmod sd_mod"?
1021          */
1022
1023         scsi_autopm_put_device(sdev);
1024         scsi_disk_put(sdkp);
1025         return 0;
1026 }
1027
1028 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1029 {
1030         struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
1031         struct scsi_device *sdp = sdkp->device;
1032         struct Scsi_Host *host = sdp->host;
1033         int diskinfo[4];
1034
1035         /* default to most commonly used values */
1036         diskinfo[0] = 0x40;     /* 1 << 6 */
1037         diskinfo[1] = 0x20;     /* 1 << 5 */
1038         diskinfo[2] = sdkp->capacity >> 11;
1039         
1040         /* override with calculated, extended default, or driver values */
1041         if (host->hostt->bios_param)
1042                 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
1043         else
1044                 scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
1045
1046         geo->heads = diskinfo[0];
1047         geo->sectors = diskinfo[1];
1048         geo->cylinders = diskinfo[2];
1049         return 0;
1050 }
1051
1052 /**
1053  *      sd_ioctl - process an ioctl
1054  *      @inode: only i_rdev/i_bdev members may be used
1055  *      @filp: only f_mode and f_flags may be used
1056  *      @cmd: ioctl command number
1057  *      @arg: this is third argument given to ioctl(2) system call.
1058  *      Often contains a pointer.
1059  *
1060  *      Returns 0 if successful (some ioctls return positive numbers on
1061  *      success as well). Returns a negated errno value in case of error.
1062  *
1063  *      Note: most ioctls are forward onto the block subsystem or further
1064  *      down in the scsi subsystem.
1065  **/
1066 static int sd_ioctl(struct block_device *bdev, fmode_t mode,
1067                     unsigned int cmd, unsigned long arg)
1068 {
1069         struct gendisk *disk = bdev->bd_disk;
1070         struct scsi_disk *sdkp = scsi_disk(disk);
1071         struct scsi_device *sdp = sdkp->device;
1072         void __user *p = (void __user *)arg;
1073         int error;
1074     
1075         SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
1076                                     "cmd=0x%x\n", disk->disk_name, cmd));
1077
1078         /*
1079          * If we are in the middle of error recovery, don't let anyone
1080          * else try and use this device.  Also, if error recovery fails, it
1081          * may try and take the device offline, in which case all further
1082          * access to the device is prohibited.
1083          */
1084         error = scsi_nonblockable_ioctl(sdp, cmd, p,
1085                                         (mode & FMODE_NDELAY) != 0);
1086         if (!scsi_block_when_processing_errors(sdp) || !error)
1087                 goto out;
1088
1089         /*
1090          * Send SCSI addressing ioctls directly to mid level, send other
1091          * ioctls to block level and then onto mid level if they can't be
1092          * resolved.
1093          */
1094         switch (cmd) {
1095                 case SCSI_IOCTL_GET_IDLUN:
1096                 case SCSI_IOCTL_GET_BUS_NUMBER:
1097                         error = scsi_ioctl(sdp, cmd, p);
1098                         break;
1099                 default:
1100                         error = scsi_cmd_ioctl(disk->queue, disk, mode, cmd, p);
1101                         if (error != -ENOTTY)
1102                                 break;
1103                         error = scsi_ioctl(sdp, cmd, p);
1104                         break;
1105         }
1106 out:
1107         return error;
1108 }
1109
1110 static void set_media_not_present(struct scsi_disk *sdkp)
1111 {
1112         if (sdkp->media_present)
1113                 sdkp->device->changed = 1;
1114
1115         if (sdkp->device->removable) {
1116                 sdkp->media_present = 0;
1117                 sdkp->capacity = 0;
1118         }
1119 }
1120
1121 static int media_not_present(struct scsi_disk *sdkp,
1122                              struct scsi_sense_hdr *sshdr)
1123 {
1124         if (!scsi_sense_valid(sshdr))
1125                 return 0;
1126
1127         /* not invoked for commands that could return deferred errors */
1128         switch (sshdr->sense_key) {
1129         case UNIT_ATTENTION:
1130         case NOT_READY:
1131                 /* medium not present */
1132                 if (sshdr->asc == 0x3A) {
1133                         set_media_not_present(sdkp);
1134                         return 1;
1135                 }
1136         }
1137         return 0;
1138 }
1139
1140 /**
1141  *      sd_check_events - check media events
1142  *      @disk: kernel device descriptor
1143  *      @clearing: disk events currently being cleared
1144  *
1145  *      Returns mask of DISK_EVENT_*.
1146  *
1147  *      Note: this function is invoked from the block subsystem.
1148  **/
1149 static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
1150 {
1151         struct scsi_disk *sdkp = scsi_disk(disk);
1152         struct scsi_device *sdp = sdkp->device;
1153         struct scsi_sense_hdr *sshdr = NULL;
1154         int retval;
1155
1156         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
1157
1158         /*
1159          * If the device is offline, don't send any commands - just pretend as
1160          * if the command failed.  If the device ever comes back online, we
1161          * can deal with it then.  It is only because of unrecoverable errors
1162          * that we would ever take a device offline in the first place.
1163          */
1164         if (!scsi_device_online(sdp)) {
1165                 set_media_not_present(sdkp);
1166                 goto out;
1167         }
1168
1169         /*
1170          * Using TEST_UNIT_READY enables differentiation between drive with
1171          * no cartridge loaded - NOT READY, drive with changed cartridge -
1172          * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
1173          *
1174          * Drives that auto spin down. eg iomega jaz 1G, will be started
1175          * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
1176          * sd_revalidate() is called.
1177          */
1178         retval = -ENODEV;
1179
1180         if (scsi_block_when_processing_errors(sdp)) {
1181                 sshdr  = kzalloc(sizeof(*sshdr), GFP_KERNEL);
1182                 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES,
1183                                               sshdr);
1184         }
1185
1186         /* failed to execute TUR, assume media not present */
1187         if (host_byte(retval)) {
1188                 set_media_not_present(sdkp);
1189                 goto out;
1190         }
1191
1192         if (media_not_present(sdkp, sshdr))
1193                 goto out;
1194
1195         /*
1196          * For removable scsi disk we have to recognise the presence
1197          * of a disk in the drive.
1198          */
1199         if (!sdkp->media_present)
1200                 sdp->changed = 1;
1201         sdkp->media_present = 1;
1202 out:
1203         /*
1204          * sdp->changed is set under the following conditions:
1205          *
1206          *      Medium present state has changed in either direction.
1207          *      Device has indicated UNIT_ATTENTION.
1208          */
1209         kfree(sshdr);
1210         retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
1211         sdp->changed = 0;
1212         return retval;
1213 }
1214
1215 static int sd_sync_cache(struct scsi_disk *sdkp)
1216 {
1217         int retries, res;
1218         struct scsi_device *sdp = sdkp->device;
1219         struct scsi_sense_hdr sshdr;
1220
1221         if (!scsi_device_online(sdp))
1222                 return -ENODEV;
1223
1224
1225         for (retries = 3; retries > 0; --retries) {
1226                 unsigned char cmd[10] = { 0 };
1227
1228                 cmd[0] = SYNCHRONIZE_CACHE;
1229                 /*
1230                  * Leave the rest of the command zero to indicate
1231                  * flush everything.
1232                  */
1233                 res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
1234                                        SD_FLUSH_TIMEOUT, SD_MAX_RETRIES, NULL);
1235                 if (res == 0)
1236                         break;
1237         }
1238
1239         if (res) {
1240                 sd_print_result(sdkp, res);
1241                 if (driver_byte(res) & DRIVER_SENSE)
1242                         sd_print_sense_hdr(sdkp, &sshdr);
1243         }
1244
1245         if (res)
1246                 return -EIO;
1247         return 0;
1248 }
1249
1250 static void sd_rescan(struct device *dev)
1251 {
1252         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
1253
1254         if (sdkp) {
1255                 revalidate_disk(sdkp->disk);
1256                 scsi_disk_put(sdkp);
1257         }
1258 }
1259
1260
1261 #ifdef CONFIG_COMPAT
1262 /* 
1263  * This gets directly called from VFS. When the ioctl 
1264  * is not recognized we go back to the other translation paths. 
1265  */
1266 static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
1267                            unsigned int cmd, unsigned long arg)
1268 {
1269         struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
1270
1271         /*
1272          * If we are in the middle of error recovery, don't let anyone
1273          * else try and use this device.  Also, if error recovery fails, it
1274          * may try and take the device offline, in which case all further
1275          * access to the device is prohibited.
1276          */
1277         if (!scsi_block_when_processing_errors(sdev))
1278                 return -ENODEV;
1279                
1280         if (sdev->host->hostt->compat_ioctl) {
1281                 int ret;
1282
1283                 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
1284
1285                 return ret;
1286         }
1287
1288         /* 
1289          * Let the static ioctl translation table take care of it.
1290          */
1291         return -ENOIOCTLCMD; 
1292 }
1293 #endif
1294
1295 static const struct block_device_operations sd_fops = {
1296         .owner                  = THIS_MODULE,
1297         .open                   = sd_open,
1298         .release                = sd_release,
1299         .ioctl                  = sd_ioctl,
1300         .getgeo                 = sd_getgeo,
1301 #ifdef CONFIG_COMPAT
1302         .compat_ioctl           = sd_compat_ioctl,
1303 #endif
1304         .check_events           = sd_check_events,
1305         .revalidate_disk        = sd_revalidate_disk,
1306         .unlock_native_capacity = sd_unlock_native_capacity,
1307 };
1308
1309 static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
1310 {
1311         u64 start_lba = blk_rq_pos(scmd->request);
1312         u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
1313         u64 bad_lba;
1314         int info_valid;
1315         /*
1316          * resid is optional but mostly filled in.  When it's unused,
1317          * its value is zero, so we assume the whole buffer transferred
1318          */
1319         unsigned int transferred = scsi_bufflen(scmd) - scsi_get_resid(scmd);
1320         unsigned int good_bytes;
1321
1322         if (scmd->request->cmd_type != REQ_TYPE_FS)
1323                 return 0;
1324
1325         info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
1326                                              SCSI_SENSE_BUFFERSIZE,
1327                                              &bad_lba);
1328         if (!info_valid)
1329                 return 0;
1330
1331         if (scsi_bufflen(scmd) <= scmd->device->sector_size)
1332                 return 0;
1333
1334         if (scmd->device->sector_size < 512) {
1335                 /* only legitimate sector_size here is 256 */
1336                 start_lba <<= 1;
1337                 end_lba <<= 1;
1338         } else {
1339                 /* be careful ... don't want any overflows */
1340                 u64 factor = scmd->device->sector_size / 512;
1341                 do_div(start_lba, factor);
1342                 do_div(end_lba, factor);
1343         }
1344
1345         /* The bad lba was reported incorrectly, we have no idea where
1346          * the error is.
1347          */
1348         if (bad_lba < start_lba  || bad_lba >= end_lba)
1349                 return 0;
1350
1351         /* This computation should always be done in terms of
1352          * the resolution of the device's medium.
1353          */
1354         good_bytes = (bad_lba - start_lba) * scmd->device->sector_size;
1355         return min(good_bytes, transferred);
1356 }
1357
1358 /**
1359  *      sd_done - bottom half handler: called when the lower level
1360  *      driver has completed (successfully or otherwise) a scsi command.
1361  *      @SCpnt: mid-level's per command structure.
1362  *
1363  *      Note: potentially run from within an ISR. Must not block.
1364  **/
1365 static int sd_done(struct scsi_cmnd *SCpnt)
1366 {
1367         int result = SCpnt->result;
1368         unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
1369         struct scsi_sense_hdr sshdr;
1370         struct scsi_disk *sdkp = scsi_disk(SCpnt->request->rq_disk);
1371         int sense_valid = 0;
1372         int sense_deferred = 0;
1373         unsigned char op = SCpnt->cmnd[0];
1374
1375         if ((SCpnt->request->cmd_flags & REQ_DISCARD) && !result)
1376                 scsi_set_resid(SCpnt, 0);
1377
1378         if (result) {
1379                 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
1380                 if (sense_valid)
1381                         sense_deferred = scsi_sense_is_deferred(&sshdr);
1382         }
1383 #ifdef CONFIG_SCSI_LOGGING
1384         SCSI_LOG_HLCOMPLETE(1, scsi_print_result(SCpnt));
1385         if (sense_valid) {
1386                 SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
1387                                                    "sd_done: sb[respc,sk,asc,"
1388                                                    "ascq]=%x,%x,%x,%x\n",
1389                                                    sshdr.response_code,
1390                                                    sshdr.sense_key, sshdr.asc,
1391                                                    sshdr.ascq));
1392         }
1393 #endif
1394         if (driver_byte(result) != DRIVER_SENSE &&
1395             (!sense_valid || sense_deferred))
1396                 goto out;
1397
1398         switch (sshdr.sense_key) {
1399         case HARDWARE_ERROR:
1400         case MEDIUM_ERROR:
1401                 good_bytes = sd_completed_bytes(SCpnt);
1402                 break;
1403         case RECOVERED_ERROR:
1404                 good_bytes = scsi_bufflen(SCpnt);
1405                 break;
1406         case NO_SENSE:
1407                 /* This indicates a false check condition, so ignore it.  An
1408                  * unknown amount of data was transferred so treat it as an
1409                  * error.
1410                  */
1411                 scsi_print_sense("sd", SCpnt);
1412                 SCpnt->result = 0;
1413                 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1414                 break;
1415         case ABORTED_COMMAND:
1416                 if (sshdr.asc == 0x10)  /* DIF: Target detected corruption */
1417                         good_bytes = sd_completed_bytes(SCpnt);
1418                 break;
1419         case ILLEGAL_REQUEST:
1420                 if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
1421                         good_bytes = sd_completed_bytes(SCpnt);
1422                 /* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
1423                 if ((sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1424                     (op == UNMAP || op == WRITE_SAME_16 || op == WRITE_SAME))
1425                         sd_config_discard(sdkp, SD_LBP_DISABLE);
1426                 break;
1427         default:
1428                 break;
1429         }
1430  out:
1431         if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
1432                 sd_dif_complete(SCpnt, good_bytes);
1433
1434         if (scsi_host_dif_capable(sdkp->device->host, sdkp->protection_type)
1435             == SD_DIF_TYPE2_PROTECTION && SCpnt->cmnd != SCpnt->request->cmd) {
1436
1437                 /* We have to print a failed command here as the
1438                  * extended CDB gets freed before scsi_io_completion()
1439                  * is called.
1440                  */
1441                 if (result)
1442                         scsi_print_command(SCpnt);
1443
1444                 mempool_free(SCpnt->cmnd, sd_cdb_pool);
1445                 SCpnt->cmnd = NULL;
1446                 SCpnt->cmd_len = 0;
1447         }
1448
1449         return good_bytes;
1450 }
1451
1452 /*
1453  * spinup disk - called only in sd_revalidate_disk()
1454  */
1455 static void
1456 sd_spinup_disk(struct scsi_disk *sdkp)
1457 {
1458         unsigned char cmd[10];
1459         unsigned long spintime_expire = 0;
1460         int retries, spintime;
1461         unsigned int the_result;
1462         struct scsi_sense_hdr sshdr;
1463         int sense_valid = 0;
1464
1465         spintime = 0;
1466
1467         /* Spin up drives, as required.  Only do this at boot time */
1468         /* Spinup needs to be done for module loads too. */
1469         do {
1470                 retries = 0;
1471
1472                 do {
1473                         cmd[0] = TEST_UNIT_READY;
1474                         memset((void *) &cmd[1], 0, 9);
1475
1476                         the_result = scsi_execute_req(sdkp->device, cmd,
1477                                                       DMA_NONE, NULL, 0,
1478                                                       &sshdr, SD_TIMEOUT,
1479                                                       SD_MAX_RETRIES, NULL);
1480
1481                         /*
1482                          * If the drive has indicated to us that it
1483                          * doesn't have any media in it, don't bother
1484                          * with any more polling.
1485                          */
1486                         if (media_not_present(sdkp, &sshdr))
1487                                 return;
1488
1489                         if (the_result)
1490                                 sense_valid = scsi_sense_valid(&sshdr);
1491                         retries++;
1492                 } while (retries < 3 && 
1493                          (!scsi_status_is_good(the_result) ||
1494                           ((driver_byte(the_result) & DRIVER_SENSE) &&
1495                           sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
1496
1497                 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
1498                         /* no sense, TUR either succeeded or failed
1499                          * with a status error */
1500                         if(!spintime && !scsi_status_is_good(the_result)) {
1501                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1502                                 sd_print_result(sdkp, the_result);
1503                         }
1504                         break;
1505                 }
1506                                         
1507                 /*
1508                  * The device does not want the automatic start to be issued.
1509                  */
1510                 if (sdkp->device->no_start_on_add)
1511                         break;
1512
1513                 if (sense_valid && sshdr.sense_key == NOT_READY) {
1514                         if (sshdr.asc == 4 && sshdr.ascq == 3)
1515                                 break;  /* manual intervention required */
1516                         if (sshdr.asc == 4 && sshdr.ascq == 0xb)
1517                                 break;  /* standby */
1518                         if (sshdr.asc == 4 && sshdr.ascq == 0xc)
1519                                 break;  /* unavailable */
1520                         /*
1521                          * Issue command to spin up drive when not ready
1522                          */
1523                         if (!spintime) {
1524                                 sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
1525                                 cmd[0] = START_STOP;
1526                                 cmd[1] = 1;     /* Return immediately */
1527                                 memset((void *) &cmd[2], 0, 8);
1528                                 cmd[4] = 1;     /* Start spin cycle */
1529                                 if (sdkp->device->start_stop_pwr_cond)
1530                                         cmd[4] |= 1 << 4;
1531                                 scsi_execute_req(sdkp->device, cmd, DMA_NONE,
1532                                                  NULL, 0, &sshdr,
1533                                                  SD_TIMEOUT, SD_MAX_RETRIES,
1534                                                  NULL);
1535                                 spintime_expire = jiffies + 100 * HZ;
1536                                 spintime = 1;
1537                         }
1538                         /* Wait 1 second for next try */
1539                         msleep(1000);
1540                         printk(".");
1541
1542                 /*
1543                  * Wait for USB flash devices with slow firmware.
1544                  * Yes, this sense key/ASC combination shouldn't
1545                  * occur here.  It's characteristic of these devices.
1546                  */
1547                 } else if (sense_valid &&
1548                                 sshdr.sense_key == UNIT_ATTENTION &&
1549                                 sshdr.asc == 0x28) {
1550                         if (!spintime) {
1551                                 spintime_expire = jiffies + 5 * HZ;
1552                                 spintime = 1;
1553                         }
1554                         /* Wait 1 second for next try */
1555                         msleep(1000);
1556                 } else {
1557                         /* we don't understand the sense code, so it's
1558                          * probably pointless to loop */
1559                         if(!spintime) {
1560                                 sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1561                                 sd_print_sense_hdr(sdkp, &sshdr);
1562                         }
1563                         break;
1564                 }
1565                                 
1566         } while (spintime && time_before_eq(jiffies, spintime_expire));
1567
1568         if (spintime) {
1569                 if (scsi_status_is_good(the_result))
1570                         printk("ready\n");
1571                 else
1572                         printk("not responding...\n");
1573         }
1574 }
1575
1576
1577 /*
1578  * Determine whether disk supports Data Integrity Field.
1579  */
1580 static void sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
1581 {
1582         struct scsi_device *sdp = sdkp->device;
1583         u8 type;
1584
1585         if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
1586                 return;
1587
1588         type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
1589
1590         if (type == sdkp->protection_type || !sdkp->first_scan)
1591                 return;
1592
1593         sdkp->protection_type = type;
1594
1595         if (type > SD_DIF_TYPE3_PROTECTION) {
1596                 sd_printk(KERN_ERR, sdkp, "formatted with unsupported " \
1597                           "protection type %u. Disabling disk!\n", type);
1598                 sdkp->capacity = 0;
1599                 return;
1600         }
1601
1602         if (scsi_host_dif_capable(sdp->host, type))
1603                 sd_printk(KERN_NOTICE, sdkp,
1604                           "Enabling DIF Type %u protection\n", type);
1605         else
1606                 sd_printk(KERN_NOTICE, sdkp,
1607                           "Disabling DIF Type %u protection\n", type);
1608 }
1609
1610 static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
1611                         struct scsi_sense_hdr *sshdr, int sense_valid,
1612                         int the_result)
1613 {
1614         sd_print_result(sdkp, the_result);
1615         if (driver_byte(the_result) & DRIVER_SENSE)
1616                 sd_print_sense_hdr(sdkp, sshdr);
1617         else
1618                 sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
1619
1620         /*
1621          * Set dirty bit for removable devices if not ready -
1622          * sometimes drives will not report this properly.
1623          */
1624         if (sdp->removable &&
1625             sense_valid && sshdr->sense_key == NOT_READY)
1626                 set_media_not_present(sdkp);
1627
1628         /*
1629          * We used to set media_present to 0 here to indicate no media
1630          * in the drive, but some drives fail read capacity even with
1631          * media present, so we can't do that.
1632          */
1633         sdkp->capacity = 0; /* unknown mapped to zero - as usual */
1634 }
1635
1636 #define RC16_LEN 32
1637 #if RC16_LEN > SD_BUF_SIZE
1638 #error RC16_LEN must not be more than SD_BUF_SIZE
1639 #endif
1640
1641 #define READ_CAPACITY_RETRIES_ON_RESET  10
1642
1643 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
1644                                                 unsigned char *buffer)
1645 {
1646         unsigned char cmd[16];
1647         struct scsi_sense_hdr sshdr;
1648         int sense_valid = 0;
1649         int the_result;
1650         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1651         unsigned int alignment;
1652         unsigned long long lba;
1653         unsigned sector_size;
1654
1655         if (sdp->no_read_capacity_16)
1656                 return -EINVAL;
1657
1658         do {
1659                 memset(cmd, 0, 16);
1660                 cmd[0] = SERVICE_ACTION_IN;
1661                 cmd[1] = SAI_READ_CAPACITY_16;
1662                 cmd[13] = RC16_LEN;
1663                 memset(buffer, 0, RC16_LEN);
1664
1665                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1666                                         buffer, RC16_LEN, &sshdr,
1667                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1668
1669                 if (media_not_present(sdkp, &sshdr))
1670                         return -ENODEV;
1671
1672                 if (the_result) {
1673                         sense_valid = scsi_sense_valid(&sshdr);
1674                         if (sense_valid &&
1675                             sshdr.sense_key == ILLEGAL_REQUEST &&
1676                             (sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
1677                             sshdr.ascq == 0x00)
1678                                 /* Invalid Command Operation Code or
1679                                  * Invalid Field in CDB, just retry
1680                                  * silently with RC10 */
1681                                 return -EINVAL;
1682                         if (sense_valid &&
1683                             sshdr.sense_key == UNIT_ATTENTION &&
1684                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1685                                 /* Device reset might occur several times,
1686                                  * give it one more chance */
1687                                 if (--reset_retries > 0)
1688                                         continue;
1689                 }
1690                 retries--;
1691
1692         } while (the_result && retries);
1693
1694         if (the_result) {
1695                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY(16) failed\n");
1696                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1697                 return -EINVAL;
1698         }
1699
1700         sector_size = get_unaligned_be32(&buffer[8]);
1701         lba = get_unaligned_be64(&buffer[0]);
1702
1703         sd_read_protection_type(sdkp, buffer);
1704
1705         if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
1706                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1707                         "kernel compiled with support for large block "
1708                         "devices.\n");
1709                 sdkp->capacity = 0;
1710                 return -EOVERFLOW;
1711         }
1712
1713         /* Logical blocks per physical block exponent */
1714         sdkp->physical_block_size = (1 << (buffer[13] & 0xf)) * sector_size;
1715
1716         /* Lowest aligned logical block */
1717         alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size;
1718         blk_queue_alignment_offset(sdp->request_queue, alignment);
1719         if (alignment && sdkp->first_scan)
1720                 sd_printk(KERN_NOTICE, sdkp,
1721                           "physical block alignment offset: %u\n", alignment);
1722
1723         if (buffer[14] & 0x80) { /* LBPME */
1724                 sdkp->lbpme = 1;
1725
1726                 if (buffer[14] & 0x40) /* LBPRZ */
1727                         sdkp->lbprz = 1;
1728
1729                 sd_config_discard(sdkp, SD_LBP_WS16);
1730         }
1731
1732         sdkp->capacity = lba + 1;
1733         return sector_size;
1734 }
1735
1736 static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
1737                                                 unsigned char *buffer)
1738 {
1739         unsigned char cmd[16];
1740         struct scsi_sense_hdr sshdr;
1741         int sense_valid = 0;
1742         int the_result;
1743         int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
1744         sector_t lba;
1745         unsigned sector_size;
1746
1747         do {
1748                 cmd[0] = READ_CAPACITY;
1749                 memset(&cmd[1], 0, 9);
1750                 memset(buffer, 0, 8);
1751
1752                 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
1753                                         buffer, 8, &sshdr,
1754                                         SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1755
1756                 if (media_not_present(sdkp, &sshdr))
1757                         return -ENODEV;
1758
1759                 if (the_result) {
1760                         sense_valid = scsi_sense_valid(&sshdr);
1761                         if (sense_valid &&
1762                             sshdr.sense_key == UNIT_ATTENTION &&
1763                             sshdr.asc == 0x29 && sshdr.ascq == 0x00)
1764                                 /* Device reset might occur several times,
1765                                  * give it one more chance */
1766                                 if (--reset_retries > 0)
1767                                         continue;
1768                 }
1769                 retries--;
1770
1771         } while (the_result && retries);
1772
1773         if (the_result) {
1774                 sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY failed\n");
1775                 read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
1776                 return -EINVAL;
1777         }
1778
1779         sector_size = get_unaligned_be32(&buffer[4]);
1780         lba = get_unaligned_be32(&buffer[0]);
1781
1782         if (sdp->no_read_capacity_16 && (lba == 0xffffffff)) {
1783                 /* Some buggy (usb cardreader) devices return an lba of
1784                    0xffffffff when the want to report a size of 0 (with
1785                    which they really mean no media is present) */
1786                 sdkp->capacity = 0;
1787                 sdkp->physical_block_size = sector_size;
1788                 return sector_size;
1789         }
1790
1791         if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
1792                 sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
1793                         "kernel compiled with support for large block "
1794                         "devices.\n");
1795                 sdkp->capacity = 0;
1796                 return -EOVERFLOW;
1797         }
1798
1799         sdkp->capacity = lba + 1;
1800         sdkp->physical_block_size = sector_size;
1801         return sector_size;
1802 }
1803
1804 static int sd_try_rc16_first(struct scsi_device *sdp)
1805 {
1806         if (sdp->host->max_cmd_len < 16)
1807                 return 0;
1808         if (sdp->scsi_level > SCSI_SPC_2)
1809                 return 1;
1810         if (scsi_device_protection(sdp))
1811                 return 1;
1812         return 0;
1813 }
1814
1815 /*
1816  * read disk capacity
1817  */
1818 static void
1819 sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
1820 {
1821         int sector_size;
1822         struct scsi_device *sdp = sdkp->device;
1823         sector_t old_capacity = sdkp->capacity;
1824
1825         if (sd_try_rc16_first(sdp)) {
1826                 sector_size = read_capacity_16(sdkp, sdp, buffer);
1827                 if (sector_size == -EOVERFLOW)
1828                         goto got_data;
1829                 if (sector_size == -ENODEV)
1830                         return;
1831                 if (sector_size < 0)
1832                         sector_size = read_capacity_10(sdkp, sdp, buffer);
1833                 if (sector_size < 0)
1834                         return;
1835         } else {
1836                 sector_size = read_capacity_10(sdkp, sdp, buffer);
1837                 if (sector_size == -EOVERFLOW)
1838                         goto got_data;
1839                 if (sector_size < 0)
1840                         return;
1841                 if ((sizeof(sdkp->capacity) > 4) &&
1842                     (sdkp->capacity > 0xffffffffULL)) {
1843                         int old_sector_size = sector_size;
1844                         sd_printk(KERN_NOTICE, sdkp, "Very big device. "
1845                                         "Trying to use READ CAPACITY(16).\n");
1846                         sector_size = read_capacity_16(sdkp, sdp, buffer);
1847                         if (sector_size < 0) {
1848                                 sd_printk(KERN_NOTICE, sdkp,
1849                                         "Using 0xffffffff as device size\n");
1850                                 sdkp->capacity = 1 + (sector_t) 0xffffffff;
1851                                 sector_size = old_sector_size;
1852                                 goto got_data;
1853                         }
1854                 }
1855         }
1856
1857         /* Some devices are known to return the total number of blocks,
1858          * not the highest block number.  Some devices have versions
1859          * which do this and others which do not.  Some devices we might
1860          * suspect of doing this but we don't know for certain.
1861          *
1862          * If we know the reported capacity is wrong, decrement it.  If
1863          * we can only guess, then assume the number of blocks is even
1864          * (usually true but not always) and err on the side of lowering
1865          * the capacity.
1866          */
1867         if (sdp->fix_capacity ||
1868             (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
1869                 sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
1870                                 "from its reported value: %llu\n",
1871                                 (unsigned long long) sdkp->capacity);
1872                 --sdkp->capacity;
1873         }
1874
1875 got_data:
1876         if (sector_size == 0) {
1877                 sector_size = 512;
1878                 sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
1879                           "assuming 512.\n");
1880         }
1881
1882         if (sector_size != 512 &&
1883             sector_size != 1024 &&
1884             sector_size != 2048 &&
1885             sector_size != 4096 &&
1886             sector_size != 256) {
1887                 sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
1888                           sector_size);
1889                 /*
1890                  * The user might want to re-format the drive with
1891                  * a supported sectorsize.  Once this happens, it
1892                  * would be relatively trivial to set the thing up.
1893                  * For this reason, we leave the thing in the table.
1894                  */
1895                 sdkp->capacity = 0;
1896                 /*
1897                  * set a bogus sector size so the normal read/write
1898                  * logic in the block layer will eventually refuse any
1899                  * request on this device without tripping over power
1900                  * of two sector size assumptions
1901                  */
1902                 sector_size = 512;
1903         }
1904         blk_queue_logical_block_size(sdp->request_queue, sector_size);
1905
1906         {
1907                 char cap_str_2[10], cap_str_10[10];
1908                 u64 sz = (u64)sdkp->capacity << ilog2(sector_size);
1909
1910                 string_get_size(sz, STRING_UNITS_2, cap_str_2,
1911                                 sizeof(cap_str_2));
1912                 string_get_size(sz, STRING_UNITS_10, cap_str_10,
1913                                 sizeof(cap_str_10));
1914
1915                 if (sdkp->first_scan || old_capacity != sdkp->capacity) {
1916                         sd_printk(KERN_NOTICE, sdkp,
1917                                   "%llu %d-byte logical blocks: (%s/%s)\n",
1918                                   (unsigned long long)sdkp->capacity,
1919                                   sector_size, cap_str_10, cap_str_2);
1920
1921                         if (sdkp->physical_block_size != sector_size)
1922                                 sd_printk(KERN_NOTICE, sdkp,
1923                                           "%u-byte physical blocks\n",
1924                                           sdkp->physical_block_size);
1925                 }
1926         }
1927
1928         /* Rescale capacity to 512-byte units */
1929         if (sector_size == 4096)
1930                 sdkp->capacity <<= 3;
1931         else if (sector_size == 2048)
1932                 sdkp->capacity <<= 2;
1933         else if (sector_size == 1024)
1934                 sdkp->capacity <<= 1;
1935         else if (sector_size == 256)
1936                 sdkp->capacity >>= 1;
1937
1938         blk_queue_physical_block_size(sdp->request_queue,
1939                                       sdkp->physical_block_size);
1940         sdkp->device->sector_size = sector_size;
1941 }
1942
1943 /* called with buffer of length 512 */
1944 static inline int
1945 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
1946                  unsigned char *buffer, int len, struct scsi_mode_data *data,
1947                  struct scsi_sense_hdr *sshdr)
1948 {
1949         return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
1950                                SD_TIMEOUT, SD_MAX_RETRIES, data,
1951                                sshdr);
1952 }
1953
1954 /*
1955  * read write protect setting, if possible - called only in sd_revalidate_disk()
1956  * called with buffer of length SD_BUF_SIZE
1957  */
1958 static void
1959 sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
1960 {
1961         int res;
1962         struct scsi_device *sdp = sdkp->device;
1963         struct scsi_mode_data data;
1964         int old_wp = sdkp->write_prot;
1965
1966         set_disk_ro(sdkp->disk, 0);
1967         if (sdp->skip_ms_page_3f) {
1968                 sd_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
1969                 return;
1970         }
1971
1972         if (sdp->use_192_bytes_for_3f) {
1973                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
1974         } else {
1975                 /*
1976                  * First attempt: ask for all pages (0x3F), but only 4 bytes.
1977                  * We have to start carefully: some devices hang if we ask
1978                  * for more than is available.
1979                  */
1980                 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
1981
1982                 /*
1983                  * Second attempt: ask for page 0 When only page 0 is
1984                  * implemented, a request for page 3F may return Sense Key
1985                  * 5: Illegal Request, Sense Code 24: Invalid field in
1986                  * CDB.
1987                  */
1988                 if (!scsi_status_is_good(res))
1989                         res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
1990
1991                 /*
1992                  * Third attempt: ask 255 bytes, as we did earlier.
1993                  */
1994                 if (!scsi_status_is_good(res))
1995                         res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
1996                                                &data, NULL);
1997         }
1998
1999         if (!scsi_status_is_good(res)) {
2000                 sd_printk(KERN_WARNING, sdkp,
2001                           "Test WP failed, assume Write Enabled\n");
2002         } else {
2003                 sdkp->write_prot = ((data.device_specific & 0x80) != 0);
2004                 set_disk_ro(sdkp->disk, sdkp->write_prot);
2005                 if (sdkp->first_scan || old_wp != sdkp->write_prot) {
2006                         sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
2007                                   sdkp->write_prot ? "on" : "off");
2008                         sd_printk(KERN_DEBUG, sdkp,
2009                                   "Mode Sense: %02x %02x %02x %02x\n",
2010                                   buffer[0], buffer[1], buffer[2], buffer[3]);
2011                 }
2012         }
2013 }
2014
2015 /*
2016  * sd_read_cache_type - called only from sd_revalidate_disk()
2017  * called with buffer of length SD_BUF_SIZE
2018  */
2019 static void
2020 sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
2021 {
2022         int len = 0, res;
2023         struct scsi_device *sdp = sdkp->device;
2024
2025         int dbd;
2026         int modepage;
2027         int first_len;
2028         struct scsi_mode_data data;
2029         struct scsi_sense_hdr sshdr;
2030         int old_wce = sdkp->WCE;
2031         int old_rcd = sdkp->RCD;
2032         int old_dpofua = sdkp->DPOFUA;
2033
2034         first_len = 4;
2035         if (sdp->skip_ms_page_8) {
2036                 if (sdp->type == TYPE_RBC)
2037                         goto defaults;
2038                 else {
2039                         if (sdp->skip_ms_page_3f)
2040                                 goto defaults;
2041                         modepage = 0x3F;
2042                         if (sdp->use_192_bytes_for_3f)
2043                                 first_len = 192;
2044                         dbd = 0;
2045                 }
2046         } else if (sdp->type == TYPE_RBC) {
2047                 modepage = 6;
2048                 dbd = 8;
2049         } else {
2050                 modepage = 8;
2051                 dbd = 0;
2052         }
2053
2054         /* cautiously ask */
2055         res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len,
2056                         &data, &sshdr);
2057
2058         if (!scsi_status_is_good(res))
2059                 goto bad_sense;
2060
2061         if (!data.header_length) {
2062                 modepage = 6;
2063                 first_len = 0;
2064                 sd_printk(KERN_ERR, sdkp, "Missing header in MODE_SENSE response\n");
2065         }
2066
2067         /* that went OK, now ask for the proper length */
2068         len = data.length;
2069
2070         /*
2071          * We're only interested in the first three bytes, actually.
2072          * But the data cache page is defined for the first 20.
2073          */
2074         if (len < 3)
2075                 goto bad_sense;
2076         else if (len > SD_BUF_SIZE) {
2077                 sd_printk(KERN_NOTICE, sdkp, "Truncating mode parameter "
2078                           "data from %d to %d bytes\n", len, SD_BUF_SIZE);
2079                 len = SD_BUF_SIZE;
2080         }
2081         if (modepage == 0x3F && sdp->use_192_bytes_for_3f)
2082                 len = 192;
2083
2084         /* Get the data */
2085         if (len > first_len)
2086                 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len,
2087                                 &data, &sshdr);
2088
2089         if (scsi_status_is_good(res)) {
2090                 int offset = data.header_length + data.block_descriptor_length;
2091
2092                 while (offset < len) {
2093                         u8 page_code = buffer[offset] & 0x3F;
2094                         u8 spf       = buffer[offset] & 0x40;
2095
2096                         if (page_code == 8 || page_code == 6) {
2097                                 /* We're interested only in the first 3 bytes.
2098                                  */
2099                                 if (len - offset <= 2) {
2100                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2101                                                   "mode parameter data\n");
2102                                         goto defaults;
2103                                 } else {
2104                                         modepage = page_code;
2105                                         goto Page_found;
2106                                 }
2107                         } else {
2108                                 /* Go to the next page */
2109                                 if (spf && len - offset > 3)
2110                                         offset += 4 + (buffer[offset+2] << 8) +
2111                                                 buffer[offset+3];
2112                                 else if (!spf && len - offset > 1)
2113                                         offset += 2 + buffer[offset+1];
2114                                 else {
2115                                         sd_printk(KERN_ERR, sdkp, "Incomplete "
2116                                                   "mode parameter data\n");
2117                                         goto defaults;
2118                                 }
2119                         }
2120                 }
2121
2122                 if (modepage == 0x3F) {
2123                         sd_printk(KERN_ERR, sdkp, "No Caching mode page "
2124                                   "present\n");
2125                         goto defaults;
2126                 } else if ((buffer[offset] & 0x3f) != modepage) {
2127                         sd_printk(KERN_ERR, sdkp, "Got wrong page\n");
2128                         goto defaults;
2129                 }
2130         Page_found:
2131                 if (modepage == 8) {
2132                         sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
2133                         sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
2134                 } else {
2135                         sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
2136                         sdkp->RCD = 0;
2137                 }
2138
2139                 sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
2140                 if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
2141                         sd_printk(KERN_NOTICE, sdkp,
2142                                   "Uses READ/WRITE(6), disabling FUA\n");
2143                         sdkp->DPOFUA = 0;
2144                 }
2145
2146                 if (sdkp->first_scan || old_wce != sdkp->WCE ||
2147                     old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
2148                         sd_printk(KERN_NOTICE, sdkp,
2149                                   "Write cache: %s, read cache: %s, %s\n",
2150                                   sdkp->WCE ? "enabled" : "disabled",
2151                                   sdkp->RCD ? "disabled" : "enabled",
2152                                   sdkp->DPOFUA ? "supports DPO and FUA"
2153                                   : "doesn't support DPO or FUA");
2154
2155                 return;
2156         }
2157
2158 bad_sense:
2159         if (scsi_sense_valid(&sshdr) &&
2160             sshdr.sense_key == ILLEGAL_REQUEST &&
2161             sshdr.asc == 0x24 && sshdr.ascq == 0x0)
2162                 /* Invalid field in CDB */
2163                 sd_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
2164         else
2165                 sd_printk(KERN_ERR, sdkp, "Asking for cache data failed\n");
2166
2167 defaults:
2168         sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n");
2169         sdkp->WCE = 0;
2170         sdkp->RCD = 0;
2171         sdkp->DPOFUA = 0;
2172 }
2173
2174 /*
2175  * The ATO bit indicates whether the DIF application tag is available
2176  * for use by the operating system.
2177  */
2178 static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
2179 {
2180         int res, offset;
2181         struct scsi_device *sdp = sdkp->device;
2182         struct scsi_mode_data data;
2183         struct scsi_sense_hdr sshdr;
2184
2185         if (sdp->type != TYPE_DISK)
2186                 return;
2187
2188         if (sdkp->protection_type == 0)
2189                 return;
2190
2191         res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
2192                               SD_MAX_RETRIES, &data, &sshdr);
2193
2194         if (!scsi_status_is_good(res) || !data.header_length ||
2195             data.length < 6) {
2196                 sd_printk(KERN_WARNING, sdkp,
2197                           "getting Control mode page failed, assume no ATO\n");
2198
2199                 if (scsi_sense_valid(&sshdr))
2200                         sd_print_sense_hdr(sdkp, &sshdr);
2201
2202                 return;
2203         }
2204
2205         offset = data.header_length + data.block_descriptor_length;
2206
2207         if ((buffer[offset] & 0x3f) != 0x0a) {
2208                 sd_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
2209                 return;
2210         }
2211
2212         if ((buffer[offset + 5] & 0x80) == 0)
2213                 return;
2214
2215         sdkp->ATO = 1;
2216
2217         return;
2218 }
2219
2220 /**
2221  * sd_read_block_limits - Query disk device for preferred I/O sizes.
2222  * @disk: disk to query
2223  */
2224 static void sd_read_block_limits(struct scsi_disk *sdkp)
2225 {
2226         unsigned int sector_sz = sdkp->device->sector_size;
2227         const int vpd_len = 64;
2228         unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
2229
2230         if (!buffer ||
2231             /* Block Limits VPD */
2232             scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
2233                 goto out;
2234
2235         blk_queue_io_min(sdkp->disk->queue,
2236                          get_unaligned_be16(&buffer[6]) * sector_sz);
2237         blk_queue_io_opt(sdkp->disk->queue,
2238                          get_unaligned_be32(&buffer[12]) * sector_sz);
2239
2240         if (buffer[3] == 0x3c) {
2241                 unsigned int lba_count, desc_count;
2242
2243                 sdkp->max_ws_blocks =
2244                         (u32) min_not_zero(get_unaligned_be64(&buffer[36]),
2245                                            (u64)0xffffffff);
2246
2247                 if (!sdkp->lbpme)
2248                         goto out;
2249
2250                 lba_count = get_unaligned_be32(&buffer[20]);
2251                 desc_count = get_unaligned_be32(&buffer[24]);
2252
2253                 if (lba_count && desc_count)
2254                         sdkp->max_unmap_blocks = lba_count;
2255
2256                 sdkp->unmap_granularity = get_unaligned_be32(&buffer[28]);
2257
2258                 if (buffer[32] & 0x80)
2259                         sdkp->unmap_alignment =
2260                                 get_unaligned_be32(&buffer[32]) & ~(1 << 31);
2261
2262                 if (!sdkp->lbpvpd) { /* LBP VPD page not provided */
2263
2264                         if (sdkp->max_unmap_blocks)
2265                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2266                         else
2267                                 sd_config_discard(sdkp, SD_LBP_WS16);
2268
2269                 } else {        /* LBP VPD page tells us what to use */
2270
2271                         if (sdkp->lbpu && sdkp->max_unmap_blocks)
2272                                 sd_config_discard(sdkp, SD_LBP_UNMAP);
2273                         else if (sdkp->lbpws)
2274                                 sd_config_discard(sdkp, SD_LBP_WS16);
2275                         else if (sdkp->lbpws10)
2276                                 sd_config_discard(sdkp, SD_LBP_WS10);
2277                         else
2278                                 sd_config_discard(sdkp, SD_LBP_DISABLE);
2279                 }
2280         }
2281
2282  out:
2283         kfree(buffer);
2284 }
2285
2286 /**
2287  * sd_read_block_characteristics - Query block dev. characteristics
2288  * @disk: disk to query
2289  */
2290 static void sd_read_block_characteristics(struct scsi_disk *sdkp)
2291 {
2292         unsigned char *buffer;
2293         u16 rot;
2294         const int vpd_len = 64;
2295
2296         buffer = kmalloc(vpd_len, GFP_KERNEL);
2297
2298         if (!buffer ||
2299             /* Block Device Characteristics VPD */
2300             scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
2301                 goto out;
2302
2303         rot = get_unaligned_be16(&buffer[4]);
2304
2305         if (rot == 1)
2306                 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
2307
2308  out:
2309         kfree(buffer);
2310 }
2311
2312 /**
2313  * sd_read_block_provisioning - Query provisioning VPD page
2314  * @disk: disk to query
2315  */
2316 static void sd_read_block_provisioning(struct scsi_disk *sdkp)
2317 {
2318         unsigned char *buffer;
2319         const int vpd_len = 8;
2320
2321         if (sdkp->lbpme == 0)
2322                 return;
2323
2324         buffer = kmalloc(vpd_len, GFP_KERNEL);
2325
2326         if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
2327                 goto out;
2328
2329         sdkp->lbpvpd    = 1;
2330         sdkp->lbpu      = (buffer[5] >> 7) & 1; /* UNMAP */
2331         sdkp->lbpws     = (buffer[5] >> 6) & 1; /* WRITE SAME(16) with UNMAP */
2332         sdkp->lbpws10   = (buffer[5] >> 5) & 1; /* WRITE SAME(10) with UNMAP */
2333
2334  out:
2335         kfree(buffer);
2336 }
2337
2338 static int sd_try_extended_inquiry(struct scsi_device *sdp)
2339 {
2340         /*
2341          * Although VPD inquiries can go to SCSI-2 type devices,
2342          * some USB ones crash on receiving them, and the pages
2343          * we currently ask for are for SPC-3 and beyond
2344          */
2345         if (sdp->scsi_level > SCSI_SPC_2)
2346                 return 1;
2347         return 0;
2348 }
2349
2350 /**
2351  *      sd_revalidate_disk - called the first time a new disk is seen,
2352  *      performs disk spin up, read_capacity, etc.
2353  *      @disk: struct gendisk we care about
2354  **/
2355 static int sd_revalidate_disk(struct gendisk *disk)
2356 {
2357         struct scsi_disk *sdkp = scsi_disk(disk);
2358         struct scsi_device *sdp = sdkp->device;
2359         unsigned char *buffer;
2360         unsigned flush = 0;
2361
2362         SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
2363                                       "sd_revalidate_disk\n"));
2364
2365         /*
2366          * If the device is offline, don't try and read capacity or any
2367          * of the other niceties.
2368          */
2369         if (!scsi_device_online(sdp))
2370                 goto out;
2371
2372         buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
2373         if (!buffer) {
2374                 sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
2375                           "allocation failure.\n");
2376                 goto out;
2377         }
2378
2379         sd_spinup_disk(sdkp);
2380
2381         /*
2382          * Without media there is no reason to ask; moreover, some devices
2383          * react badly if we do.
2384          */
2385         if (sdkp->media_present) {
2386                 sd_read_capacity(sdkp, buffer);
2387
2388                 if (sd_try_extended_inquiry(sdp)) {
2389                         sd_read_block_provisioning(sdkp);
2390                         sd_read_block_limits(sdkp);
2391                         sd_read_block_characteristics(sdkp);
2392                 }
2393
2394                 sd_read_write_protect_flag(sdkp, buffer);
2395                 sd_read_cache_type(sdkp, buffer);
2396                 sd_read_app_tag_own(sdkp, buffer);
2397         }
2398
2399         sdkp->first_scan = 0;
2400
2401         /*
2402          * We now have all cache related info, determine how we deal
2403          * with flush requests.
2404          */
2405         if (sdkp->WCE) {
2406                 flush |= REQ_FLUSH;
2407                 if (sdkp->DPOFUA)
2408                         flush |= REQ_FUA;
2409         }
2410
2411         blk_queue_flush(sdkp->disk->queue, flush);
2412
2413         set_capacity(disk, sdkp->capacity);
2414         kfree(buffer);
2415
2416  out:
2417         return 0;
2418 }
2419
2420 /**
2421  *      sd_unlock_native_capacity - unlock native capacity
2422  *      @disk: struct gendisk to set capacity for
2423  *
2424  *      Block layer calls this function if it detects that partitions
2425  *      on @disk reach beyond the end of the device.  If the SCSI host
2426  *      implements ->unlock_native_capacity() method, it's invoked to
2427  *      give it a chance to adjust the device capacity.
2428  *
2429  *      CONTEXT:
2430  *      Defined by block layer.  Might sleep.
2431  */
2432 static void sd_unlock_native_capacity(struct gendisk *disk)
2433 {
2434         struct scsi_device *sdev = scsi_disk(disk)->device;
2435
2436         if (sdev->host->hostt->unlock_native_capacity)
2437                 sdev->host->hostt->unlock_native_capacity(sdev);
2438 }
2439
2440 /**
2441  *      sd_format_disk_name - format disk name
2442  *      @prefix: name prefix - ie. "sd" for SCSI disks
2443  *      @index: index of the disk to format name for
2444  *      @buf: output buffer
2445  *      @buflen: length of the output buffer
2446  *
2447  *      SCSI disk names starts at sda.  The 26th device is sdz and the
2448  *      27th is sdaa.  The last one for two lettered suffix is sdzz
2449  *      which is followed by sdaaa.
2450  *
2451  *      This is basically 26 base counting with one extra 'nil' entry
2452  *      at the beginning from the second digit on and can be
2453  *      determined using similar method as 26 base conversion with the
2454  *      index shifted -1 after each digit is computed.
2455  *
2456  *      CONTEXT:
2457  *      Don't care.
2458  *
2459  *      RETURNS:
2460  *      0 on success, -errno on failure.
2461  */
2462 static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
2463 {
2464         const int base = 'z' - 'a' + 1;
2465         char *begin = buf + strlen(prefix);
2466         char *end = buf + buflen;
2467         char *p;
2468         int unit;
2469
2470         p = end - 1;
2471         *p = '\0';
2472         unit = base;
2473         do {
2474                 if (p == begin)
2475                         return -EINVAL;
2476                 *--p = 'a' + (index % unit);
2477                 index = (index / unit) - 1;
2478         } while (index >= 0);
2479
2480         memmove(begin, p, end - p);
2481         memcpy(buf, prefix, strlen(prefix));
2482
2483         return 0;
2484 }
2485
2486 /*
2487  * The asynchronous part of sd_probe
2488  */
2489 static void sd_probe_async(void *data, async_cookie_t cookie)
2490 {
2491         struct scsi_disk *sdkp = data;
2492         struct scsi_device *sdp;
2493         struct gendisk *gd;
2494         u32 index;
2495         struct device *dev;
2496
2497         sdp = sdkp->device;
2498         gd = sdkp->disk;
2499         index = sdkp->index;
2500         dev = &sdp->sdev_gendev;
2501
2502         gd->major = sd_major((index & 0xf0) >> 4);
2503         gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
2504         gd->minors = SD_MINORS;
2505
2506         gd->fops = &sd_fops;
2507         gd->private_data = &sdkp->driver;
2508         gd->queue = sdkp->device->request_queue;
2509
2510         /* defaults, until the device tells us otherwise */
2511         sdp->sector_size = 512;
2512         sdkp->capacity = 0;
2513         sdkp->media_present = 1;
2514         sdkp->write_prot = 0;
2515         sdkp->WCE = 0;
2516         sdkp->RCD = 0;
2517         sdkp->ATO = 0;
2518         sdkp->first_scan = 1;
2519
2520         sd_revalidate_disk(gd);
2521
2522         blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
2523         blk_queue_unprep_rq(sdp->request_queue, sd_unprep_fn);
2524
2525         gd->driverfs_dev = &sdp->sdev_gendev;
2526         gd->flags = GENHD_FL_EXT_DEVT;
2527         if (sdp->removable) {
2528                 gd->flags |= GENHD_FL_REMOVABLE;
2529                 gd->events |= DISK_EVENT_MEDIA_CHANGE;
2530         }
2531
2532         add_disk(gd);
2533         sd_dif_config_host(sdkp);
2534
2535         sd_revalidate_disk(gd);
2536
2537         sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
2538                   sdp->removable ? "removable " : "");
2539         scsi_autopm_put_device(sdp);
2540         put_device(&sdkp->dev);
2541 }
2542
2543 /**
2544  *      sd_probe - called during driver initialization and whenever a
2545  *      new scsi device is attached to the system. It is called once
2546  *      for each scsi device (not just disks) present.
2547  *      @dev: pointer to device object
2548  *
2549  *      Returns 0 if successful (or not interested in this scsi device 
2550  *      (e.g. scanner)); 1 when there is an error.
2551  *
2552  *      Note: this function is invoked from the scsi mid-level.
2553  *      This function sets up the mapping between a given 
2554  *      <host,channel,id,lun> (found in sdp) and new device name 
2555  *      (e.g. /dev/sda). More precisely it is the block device major 
2556  *      and minor number that is chosen here.
2557  *
2558  *      Assume sd_attach is not re-entrant (for time being)
2559  *      Also think about sd_attach() and sd_remove() running coincidentally.
2560  **/
2561 static int sd_probe(struct device *dev)
2562 {
2563         struct scsi_device *sdp = to_scsi_device(dev);
2564         struct scsi_disk *sdkp;
2565         struct gendisk *gd;
2566         int index;
2567         int error;
2568
2569         error = -ENODEV;
2570         if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
2571                 goto out;
2572
2573         SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
2574                                         "sd_attach\n"));
2575
2576         error = -ENOMEM;
2577         sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
2578         if (!sdkp)
2579                 goto out;
2580
2581         gd = alloc_disk(SD_MINORS);
2582         if (!gd)
2583                 goto out_free;
2584
2585         do {
2586                 if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
2587                         goto out_put;
2588
2589                 spin_lock(&sd_index_lock);
2590                 error = ida_get_new(&sd_index_ida, &index);
2591                 spin_unlock(&sd_index_lock);
2592         } while (error == -EAGAIN);
2593
2594         if (error) {
2595                 sdev_printk(KERN_WARNING, sdp, "sd_probe: memory exhausted.\n");
2596                 goto out_put;
2597         }
2598
2599         error = sd_format_disk_name("sd", index, gd->disk_name, DISK_NAME_LEN);
2600         if (error) {
2601                 sdev_printk(KERN_WARNING, sdp, "SCSI disk (sd) name length exceeded.\n");
2602                 goto out_free_index;
2603         }
2604
2605         sdkp->device = sdp;
2606         sdkp->driver = &sd_template;
2607         sdkp->disk = gd;
2608         sdkp->index = index;
2609         atomic_set(&sdkp->openers, 0);
2610
2611         if (!sdp->request_queue->rq_timeout) {
2612                 if (sdp->type != TYPE_MOD)
2613                         blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
2614                 else
2615                         blk_queue_rq_timeout(sdp->request_queue,
2616                                              SD_MOD_TIMEOUT);
2617         }
2618
2619         device_initialize(&sdkp->dev);
2620         sdkp->dev.parent = dev;
2621         sdkp->dev.class = &sd_disk_class;
2622         dev_set_name(&sdkp->dev, dev_name(dev));
2623
2624         if (device_add(&sdkp->dev))
2625                 goto out_free_index;
2626
2627         get_device(dev);
2628         dev_set_drvdata(dev, sdkp);
2629
2630         get_device(&sdkp->dev); /* prevent release before async_schedule */
2631         async_schedule(sd_probe_async, sdkp);
2632
2633         return 0;
2634
2635  out_free_index:
2636         spin_lock(&sd_index_lock);
2637         ida_remove(&sd_index_ida, index);
2638         spin_unlock(&sd_index_lock);
2639  out_put:
2640         put_disk(gd);
2641  out_free:
2642         kfree(sdkp);
2643  out:
2644         return error;
2645 }
2646
2647 /**
2648  *      sd_remove - called whenever a scsi disk (previously recognized by
2649  *      sd_probe) is detached from the system. It is called (potentially
2650  *      multiple times) during sd module unload.
2651  *      @sdp: pointer to mid level scsi device object
2652  *
2653  *      Note: this function is invoked from the scsi mid-level.
2654  *      This function potentially frees up a device name (e.g. /dev/sdc)
2655  *      that could be re-used by a subsequent sd_probe().
2656  *      This function is not called when the built-in sd driver is "exit-ed".
2657  **/
2658 static int sd_remove(struct device *dev)
2659 {
2660         struct scsi_disk *sdkp;
2661
2662         sdkp = dev_get_drvdata(dev);
2663         scsi_autopm_get_device(sdkp->device);
2664
2665         async_synchronize_full();
2666         blk_queue_prep_rq(sdkp->device->request_queue, scsi_prep_fn);
2667         blk_queue_unprep_rq(sdkp->device->request_queue, NULL);
2668         device_del(&sdkp->dev);
2669         del_gendisk(sdkp->disk);
2670         sd_shutdown(dev);
2671
2672         mutex_lock(&sd_ref_mutex);
2673         dev_set_drvdata(dev, NULL);
2674         put_device(&sdkp->dev);
2675         mutex_unlock(&sd_ref_mutex);
2676
2677         return 0;
2678 }
2679
2680 /**
2681  *      scsi_disk_release - Called to free the scsi_disk structure
2682  *      @dev: pointer to embedded class device
2683  *
2684  *      sd_ref_mutex must be held entering this routine.  Because it is
2685  *      called on last put, you should always use the scsi_disk_get()
2686  *      scsi_disk_put() helpers which manipulate the semaphore directly
2687  *      and never do a direct put_device.
2688  **/
2689 static void scsi_disk_release(struct device *dev)
2690 {
2691         struct scsi_disk *sdkp = to_scsi_disk(dev);
2692         struct gendisk *disk = sdkp->disk;
2693         
2694         spin_lock(&sd_index_lock);
2695         ida_remove(&sd_index_ida, sdkp->index);
2696         spin_unlock(&sd_index_lock);
2697
2698         disk->private_data = NULL;
2699         put_disk(disk);
2700         put_device(&sdkp->device->sdev_gendev);
2701
2702         kfree(sdkp);
2703 }
2704
2705 static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
2706 {
2707         unsigned char cmd[6] = { START_STOP };  /* START_VALID */
2708         struct scsi_sense_hdr sshdr;
2709         struct scsi_device *sdp = sdkp->device;
2710         int res;
2711
2712         if (start)
2713                 cmd[4] |= 1;    /* START */
2714
2715         if (sdp->start_stop_pwr_cond)
2716                 cmd[4] |= start ? 1 << 4 : 3 << 4;      /* Active or Standby */
2717
2718         if (!scsi_device_online(sdp))
2719                 return -ENODEV;
2720
2721         res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
2722                                SD_TIMEOUT, SD_MAX_RETRIES, NULL);
2723         if (res) {
2724                 sd_printk(KERN_WARNING, sdkp, "START_STOP FAILED\n");
2725                 sd_print_result(sdkp, res);
2726                 if (driver_byte(res) & DRIVER_SENSE)
2727                         sd_print_sense_hdr(sdkp, &sshdr);
2728         }
2729
2730         return res;
2731 }
2732
2733 /*
2734  * Send a SYNCHRONIZE CACHE instruction down to the device through
2735  * the normal SCSI command structure.  Wait for the command to
2736  * complete.
2737  */
2738 static void sd_shutdown(struct device *dev)
2739 {
2740         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2741
2742         if (!sdkp)
2743                 return;         /* this can happen */
2744
2745         if (pm_runtime_suspended(dev))
2746                 goto exit;
2747
2748         if (sdkp->WCE) {
2749                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
2750                 sd_sync_cache(sdkp);
2751         }
2752
2753         if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
2754                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
2755                 sd_start_stop_device(sdkp, 0);
2756         }
2757
2758 exit:
2759         scsi_disk_put(sdkp);
2760 }
2761
2762 static int sd_suspend(struct device *dev, pm_message_t mesg)
2763 {
2764         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2765         int ret = 0;
2766
2767         if (!sdkp)
2768                 return 0;       /* this can happen */
2769
2770         if (sdkp->WCE) {
2771                 sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
2772                 ret = sd_sync_cache(sdkp);
2773                 if (ret)
2774                         goto done;
2775         }
2776
2777         if ((mesg.event & PM_EVENT_SLEEP) && sdkp->device->manage_start_stop) {
2778                 sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
2779                 ret = sd_start_stop_device(sdkp, 0);
2780         }
2781
2782 done:
2783         scsi_disk_put(sdkp);
2784         return ret;
2785 }
2786
2787 static int sd_resume(struct device *dev)
2788 {
2789         struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
2790         int ret = 0;
2791
2792         if (!sdkp->device->manage_start_stop)
2793                 goto done;
2794
2795         sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
2796         ret = sd_start_stop_device(sdkp, 1);
2797
2798 done:
2799         scsi_disk_put(sdkp);
2800         return ret;
2801 }
2802
2803 /**
2804  *      init_sd - entry point for this driver (both when built in or when
2805  *      a module).
2806  *
2807  *      Note: this function registers this driver with the scsi mid-level.
2808  **/
2809 static int __init init_sd(void)
2810 {
2811         int majors = 0, i, err;
2812
2813         SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
2814
2815         for (i = 0; i < SD_MAJORS; i++)
2816                 if (register_blkdev(sd_major(i), "sd") == 0)
2817                         majors++;
2818
2819         if (!majors)
2820                 return -ENODEV;
2821
2822         err = class_register(&sd_disk_class);
2823         if (err)
2824                 goto err_out;
2825
2826         err = scsi_register_driver(&sd_template.gendrv);
2827         if (err)
2828                 goto err_out_class;
2829
2830         sd_cdb_cache = kmem_cache_create("sd_ext_cdb", SD_EXT_CDB_SIZE,
2831                                          0, 0, NULL);
2832         if (!sd_cdb_cache) {
2833                 printk(KERN_ERR "sd: can't init extended cdb cache\n");
2834                 goto err_out_class;
2835         }
2836
2837         sd_cdb_pool = mempool_create_slab_pool(SD_MEMPOOL_SIZE, sd_cdb_cache);
2838         if (!sd_cdb_pool) {
2839                 printk(KERN_ERR "sd: can't init extended cdb pool\n");
2840                 goto err_out_cache;
2841         }
2842
2843         return 0;
2844
2845 err_out_cache:
2846         kmem_cache_destroy(sd_cdb_cache);
2847
2848 err_out_class:
2849         class_unregister(&sd_disk_class);
2850 err_out:
2851         for (i = 0; i < SD_MAJORS; i++)
2852                 unregister_blkdev(sd_major(i), "sd");
2853         return err;
2854 }
2855
2856 /**
2857  *      exit_sd - exit point for this driver (when it is a module).
2858  *
2859  *      Note: this function unregisters this driver from the scsi mid-level.
2860  **/
2861 static void __exit exit_sd(void)
2862 {
2863         int i;
2864
2865         SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
2866
2867         mempool_destroy(sd_cdb_pool);
2868         kmem_cache_destroy(sd_cdb_cache);
2869
2870         scsi_unregister_driver(&sd_template.gendrv);
2871         class_unregister(&sd_disk_class);
2872
2873         for (i = 0; i < SD_MAJORS; i++)
2874                 unregister_blkdev(sd_major(i), "sd");
2875 }
2876
2877 module_init(init_sd);
2878 module_exit(exit_sd);
2879
2880 static void sd_print_sense_hdr(struct scsi_disk *sdkp,
2881                                struct scsi_sense_hdr *sshdr)
2882 {
2883         sd_printk(KERN_INFO, sdkp, " ");
2884         scsi_show_sense_hdr(sshdr);
2885         sd_printk(KERN_INFO, sdkp, " ");
2886         scsi_show_extd_sense(sshdr->asc, sshdr->ascq);
2887 }
2888
2889 static void sd_print_result(struct scsi_disk *sdkp, int result)
2890 {
2891         sd_printk(KERN_INFO, sdkp, " ");
2892         scsi_show_result(result);
2893 }
2894