xref: /linux/drivers/scsi/sd.c (revision 9cfc5c90ad38c8fc11bfd39de42a107da00871ba)
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 <linux/pr.h>
55 #include <asm/uaccess.h>
56 #include <asm/unaligned.h>
57 
58 #include <scsi/scsi.h>
59 #include <scsi/scsi_cmnd.h>
60 #include <scsi/scsi_dbg.h>
61 #include <scsi/scsi_device.h>
62 #include <scsi/scsi_driver.h>
63 #include <scsi/scsi_eh.h>
64 #include <scsi/scsi_host.h>
65 #include <scsi/scsi_ioctl.h>
66 #include <scsi/scsicam.h>
67 
68 #include "sd.h"
69 #include "scsi_priv.h"
70 #include "scsi_logging.h"
71 
72 MODULE_AUTHOR("Eric Youngdale");
73 MODULE_DESCRIPTION("SCSI disk (sd) driver");
74 MODULE_LICENSE("GPL");
75 
76 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
77 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
78 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
79 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
80 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
81 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
82 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
83 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
84 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
85 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
86 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
87 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
88 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
89 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
90 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
91 MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
92 MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
93 MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
94 MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
95 
96 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
97 #define SD_MINORS	16
98 #else
99 #define SD_MINORS	0
100 #endif
101 
102 static void sd_config_discard(struct scsi_disk *, unsigned int);
103 static void sd_config_write_same(struct scsi_disk *);
104 static int  sd_revalidate_disk(struct gendisk *);
105 static void sd_unlock_native_capacity(struct gendisk *disk);
106 static int  sd_probe(struct device *);
107 static int  sd_remove(struct device *);
108 static void sd_shutdown(struct device *);
109 static int sd_suspend_system(struct device *);
110 static int sd_suspend_runtime(struct device *);
111 static int sd_resume(struct device *);
112 static void sd_rescan(struct device *);
113 static int sd_init_command(struct scsi_cmnd *SCpnt);
114 static void sd_uninit_command(struct scsi_cmnd *SCpnt);
115 static int sd_done(struct scsi_cmnd *);
116 static int sd_eh_action(struct scsi_cmnd *, int);
117 static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
118 static void scsi_disk_release(struct device *cdev);
119 static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);
120 static void sd_print_result(const struct scsi_disk *, const char *, int);
121 
122 static DEFINE_SPINLOCK(sd_index_lock);
123 static DEFINE_IDA(sd_index_ida);
124 
125 /* This semaphore is used to mediate the 0->1 reference get in the
126  * face of object destruction (i.e. we can't allow a get on an
127  * object after last put) */
128 static DEFINE_MUTEX(sd_ref_mutex);
129 
130 static struct kmem_cache *sd_cdb_cache;
131 static mempool_t *sd_cdb_pool;
132 
133 static const char *sd_cache_types[] = {
134 	"write through", "none", "write back",
135 	"write back, no read (daft)"
136 };
137 
138 static void sd_set_flush_flag(struct scsi_disk *sdkp)
139 {
140 	unsigned flush = 0;
141 
142 	if (sdkp->WCE) {
143 		flush |= REQ_FLUSH;
144 		if (sdkp->DPOFUA)
145 			flush |= REQ_FUA;
146 	}
147 
148 	blk_queue_flush(sdkp->disk->queue, flush);
149 }
150 
151 static ssize_t
152 cache_type_store(struct device *dev, struct device_attribute *attr,
153 		 const char *buf, size_t count)
154 {
155 	int i, ct = -1, rcd, wce, sp;
156 	struct scsi_disk *sdkp = to_scsi_disk(dev);
157 	struct scsi_device *sdp = sdkp->device;
158 	char buffer[64];
159 	char *buffer_data;
160 	struct scsi_mode_data data;
161 	struct scsi_sense_hdr sshdr;
162 	static const char temp[] = "temporary ";
163 	int len;
164 
165 	if (sdp->type != TYPE_DISK)
166 		/* no cache control on RBC devices; theoretically they
167 		 * can do it, but there's probably so many exceptions
168 		 * it's not worth the risk */
169 		return -EINVAL;
170 
171 	if (strncmp(buf, temp, sizeof(temp) - 1) == 0) {
172 		buf += sizeof(temp) - 1;
173 		sdkp->cache_override = 1;
174 	} else {
175 		sdkp->cache_override = 0;
176 	}
177 
178 	for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
179 		len = strlen(sd_cache_types[i]);
180 		if (strncmp(sd_cache_types[i], buf, len) == 0 &&
181 		    buf[len] == '\n') {
182 			ct = i;
183 			break;
184 		}
185 	}
186 	if (ct < 0)
187 		return -EINVAL;
188 	rcd = ct & 0x01 ? 1 : 0;
189 	wce = (ct & 0x02) && !sdkp->write_prot ? 1 : 0;
190 
191 	if (sdkp->cache_override) {
192 		sdkp->WCE = wce;
193 		sdkp->RCD = rcd;
194 		sd_set_flush_flag(sdkp);
195 		return count;
196 	}
197 
198 	if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
199 			    SD_MAX_RETRIES, &data, NULL))
200 		return -EINVAL;
201 	len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
202 		  data.block_descriptor_length);
203 	buffer_data = buffer + data.header_length +
204 		data.block_descriptor_length;
205 	buffer_data[2] &= ~0x05;
206 	buffer_data[2] |= wce << 2 | rcd;
207 	sp = buffer_data[0] & 0x80 ? 1 : 0;
208 	buffer_data[0] &= ~0x80;
209 
210 	if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
211 			     SD_MAX_RETRIES, &data, &sshdr)) {
212 		if (scsi_sense_valid(&sshdr))
213 			sd_print_sense_hdr(sdkp, &sshdr);
214 		return -EINVAL;
215 	}
216 	revalidate_disk(sdkp->disk);
217 	return count;
218 }
219 
220 static ssize_t
221 manage_start_stop_show(struct device *dev, struct device_attribute *attr,
222 		       char *buf)
223 {
224 	struct scsi_disk *sdkp = to_scsi_disk(dev);
225 	struct scsi_device *sdp = sdkp->device;
226 
227 	return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
228 }
229 
230 static ssize_t
231 manage_start_stop_store(struct device *dev, struct device_attribute *attr,
232 			const char *buf, size_t count)
233 {
234 	struct scsi_disk *sdkp = to_scsi_disk(dev);
235 	struct scsi_device *sdp = sdkp->device;
236 
237 	if (!capable(CAP_SYS_ADMIN))
238 		return -EACCES;
239 
240 	sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);
241 
242 	return count;
243 }
244 static DEVICE_ATTR_RW(manage_start_stop);
245 
246 static ssize_t
247 allow_restart_show(struct device *dev, struct device_attribute *attr, char *buf)
248 {
249 	struct scsi_disk *sdkp = to_scsi_disk(dev);
250 
251 	return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
252 }
253 
254 static ssize_t
255 allow_restart_store(struct device *dev, struct device_attribute *attr,
256 		    const char *buf, size_t count)
257 {
258 	struct scsi_disk *sdkp = to_scsi_disk(dev);
259 	struct scsi_device *sdp = sdkp->device;
260 
261 	if (!capable(CAP_SYS_ADMIN))
262 		return -EACCES;
263 
264 	if (sdp->type != TYPE_DISK)
265 		return -EINVAL;
266 
267 	sdp->allow_restart = simple_strtoul(buf, NULL, 10);
268 
269 	return count;
270 }
271 static DEVICE_ATTR_RW(allow_restart);
272 
273 static ssize_t
274 cache_type_show(struct device *dev, struct device_attribute *attr, char *buf)
275 {
276 	struct scsi_disk *sdkp = to_scsi_disk(dev);
277 	int ct = sdkp->RCD + 2*sdkp->WCE;
278 
279 	return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
280 }
281 static DEVICE_ATTR_RW(cache_type);
282 
283 static ssize_t
284 FUA_show(struct device *dev, struct device_attribute *attr, char *buf)
285 {
286 	struct scsi_disk *sdkp = to_scsi_disk(dev);
287 
288 	return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
289 }
290 static DEVICE_ATTR_RO(FUA);
291 
292 static ssize_t
293 protection_type_show(struct device *dev, struct device_attribute *attr,
294 		     char *buf)
295 {
296 	struct scsi_disk *sdkp = to_scsi_disk(dev);
297 
298 	return snprintf(buf, 20, "%u\n", sdkp->protection_type);
299 }
300 
301 static ssize_t
302 protection_type_store(struct device *dev, struct device_attribute *attr,
303 		      const char *buf, size_t count)
304 {
305 	struct scsi_disk *sdkp = to_scsi_disk(dev);
306 	unsigned int val;
307 	int err;
308 
309 	if (!capable(CAP_SYS_ADMIN))
310 		return -EACCES;
311 
312 	err = kstrtouint(buf, 10, &val);
313 
314 	if (err)
315 		return err;
316 
317 	if (val >= 0 && val <= SD_DIF_TYPE3_PROTECTION)
318 		sdkp->protection_type = val;
319 
320 	return count;
321 }
322 static DEVICE_ATTR_RW(protection_type);
323 
324 static ssize_t
325 protection_mode_show(struct device *dev, struct device_attribute *attr,
326 		     char *buf)
327 {
328 	struct scsi_disk *sdkp = to_scsi_disk(dev);
329 	struct scsi_device *sdp = sdkp->device;
330 	unsigned int dif, dix;
331 
332 	dif = scsi_host_dif_capable(sdp->host, sdkp->protection_type);
333 	dix = scsi_host_dix_capable(sdp->host, sdkp->protection_type);
334 
335 	if (!dix && scsi_host_dix_capable(sdp->host, SD_DIF_TYPE0_PROTECTION)) {
336 		dif = 0;
337 		dix = 1;
338 	}
339 
340 	if (!dif && !dix)
341 		return snprintf(buf, 20, "none\n");
342 
343 	return snprintf(buf, 20, "%s%u\n", dix ? "dix" : "dif", dif);
344 }
345 static DEVICE_ATTR_RO(protection_mode);
346 
347 static ssize_t
348 app_tag_own_show(struct device *dev, struct device_attribute *attr, char *buf)
349 {
350 	struct scsi_disk *sdkp = to_scsi_disk(dev);
351 
352 	return snprintf(buf, 20, "%u\n", sdkp->ATO);
353 }
354 static DEVICE_ATTR_RO(app_tag_own);
355 
356 static ssize_t
357 thin_provisioning_show(struct device *dev, struct device_attribute *attr,
358 		       char *buf)
359 {
360 	struct scsi_disk *sdkp = to_scsi_disk(dev);
361 
362 	return snprintf(buf, 20, "%u\n", sdkp->lbpme);
363 }
364 static DEVICE_ATTR_RO(thin_provisioning);
365 
366 static const char *lbp_mode[] = {
367 	[SD_LBP_FULL]		= "full",
368 	[SD_LBP_UNMAP]		= "unmap",
369 	[SD_LBP_WS16]		= "writesame_16",
370 	[SD_LBP_WS10]		= "writesame_10",
371 	[SD_LBP_ZERO]		= "writesame_zero",
372 	[SD_LBP_DISABLE]	= "disabled",
373 };
374 
375 static ssize_t
376 provisioning_mode_show(struct device *dev, struct device_attribute *attr,
377 		       char *buf)
378 {
379 	struct scsi_disk *sdkp = to_scsi_disk(dev);
380 
381 	return snprintf(buf, 20, "%s\n", lbp_mode[sdkp->provisioning_mode]);
382 }
383 
384 static ssize_t
385 provisioning_mode_store(struct device *dev, struct device_attribute *attr,
386 			const char *buf, size_t count)
387 {
388 	struct scsi_disk *sdkp = to_scsi_disk(dev);
389 	struct scsi_device *sdp = sdkp->device;
390 
391 	if (!capable(CAP_SYS_ADMIN))
392 		return -EACCES;
393 
394 	if (sdp->type != TYPE_DISK)
395 		return -EINVAL;
396 
397 	if (!strncmp(buf, lbp_mode[SD_LBP_UNMAP], 20))
398 		sd_config_discard(sdkp, SD_LBP_UNMAP);
399 	else if (!strncmp(buf, lbp_mode[SD_LBP_WS16], 20))
400 		sd_config_discard(sdkp, SD_LBP_WS16);
401 	else if (!strncmp(buf, lbp_mode[SD_LBP_WS10], 20))
402 		sd_config_discard(sdkp, SD_LBP_WS10);
403 	else if (!strncmp(buf, lbp_mode[SD_LBP_ZERO], 20))
404 		sd_config_discard(sdkp, SD_LBP_ZERO);
405 	else if (!strncmp(buf, lbp_mode[SD_LBP_DISABLE], 20))
406 		sd_config_discard(sdkp, SD_LBP_DISABLE);
407 	else
408 		return -EINVAL;
409 
410 	return count;
411 }
412 static DEVICE_ATTR_RW(provisioning_mode);
413 
414 static ssize_t
415 max_medium_access_timeouts_show(struct device *dev,
416 				struct device_attribute *attr, char *buf)
417 {
418 	struct scsi_disk *sdkp = to_scsi_disk(dev);
419 
420 	return snprintf(buf, 20, "%u\n", sdkp->max_medium_access_timeouts);
421 }
422 
423 static ssize_t
424 max_medium_access_timeouts_store(struct device *dev,
425 				 struct device_attribute *attr, const char *buf,
426 				 size_t count)
427 {
428 	struct scsi_disk *sdkp = to_scsi_disk(dev);
429 	int err;
430 
431 	if (!capable(CAP_SYS_ADMIN))
432 		return -EACCES;
433 
434 	err = kstrtouint(buf, 10, &sdkp->max_medium_access_timeouts);
435 
436 	return err ? err : count;
437 }
438 static DEVICE_ATTR_RW(max_medium_access_timeouts);
439 
440 static ssize_t
441 max_write_same_blocks_show(struct device *dev, struct device_attribute *attr,
442 			   char *buf)
443 {
444 	struct scsi_disk *sdkp = to_scsi_disk(dev);
445 
446 	return snprintf(buf, 20, "%u\n", sdkp->max_ws_blocks);
447 }
448 
449 static ssize_t
450 max_write_same_blocks_store(struct device *dev, struct device_attribute *attr,
451 			    const char *buf, size_t count)
452 {
453 	struct scsi_disk *sdkp = to_scsi_disk(dev);
454 	struct scsi_device *sdp = sdkp->device;
455 	unsigned long max;
456 	int err;
457 
458 	if (!capable(CAP_SYS_ADMIN))
459 		return -EACCES;
460 
461 	if (sdp->type != TYPE_DISK)
462 		return -EINVAL;
463 
464 	err = kstrtoul(buf, 10, &max);
465 
466 	if (err)
467 		return err;
468 
469 	if (max == 0)
470 		sdp->no_write_same = 1;
471 	else if (max <= SD_MAX_WS16_BLOCKS) {
472 		sdp->no_write_same = 0;
473 		sdkp->max_ws_blocks = max;
474 	}
475 
476 	sd_config_write_same(sdkp);
477 
478 	return count;
479 }
480 static DEVICE_ATTR_RW(max_write_same_blocks);
481 
482 static struct attribute *sd_disk_attrs[] = {
483 	&dev_attr_cache_type.attr,
484 	&dev_attr_FUA.attr,
485 	&dev_attr_allow_restart.attr,
486 	&dev_attr_manage_start_stop.attr,
487 	&dev_attr_protection_type.attr,
488 	&dev_attr_protection_mode.attr,
489 	&dev_attr_app_tag_own.attr,
490 	&dev_attr_thin_provisioning.attr,
491 	&dev_attr_provisioning_mode.attr,
492 	&dev_attr_max_write_same_blocks.attr,
493 	&dev_attr_max_medium_access_timeouts.attr,
494 	NULL,
495 };
496 ATTRIBUTE_GROUPS(sd_disk);
497 
498 static struct class sd_disk_class = {
499 	.name		= "scsi_disk",
500 	.owner		= THIS_MODULE,
501 	.dev_release	= scsi_disk_release,
502 	.dev_groups	= sd_disk_groups,
503 };
504 
505 static const struct dev_pm_ops sd_pm_ops = {
506 	.suspend		= sd_suspend_system,
507 	.resume			= sd_resume,
508 	.poweroff		= sd_suspend_system,
509 	.restore		= sd_resume,
510 	.runtime_suspend	= sd_suspend_runtime,
511 	.runtime_resume		= sd_resume,
512 };
513 
514 static struct scsi_driver sd_template = {
515 	.gendrv = {
516 		.name		= "sd",
517 		.owner		= THIS_MODULE,
518 		.probe		= sd_probe,
519 		.remove		= sd_remove,
520 		.shutdown	= sd_shutdown,
521 		.pm		= &sd_pm_ops,
522 	},
523 	.rescan			= sd_rescan,
524 	.init_command		= sd_init_command,
525 	.uninit_command		= sd_uninit_command,
526 	.done			= sd_done,
527 	.eh_action		= sd_eh_action,
528 };
529 
530 /*
531  * Dummy kobj_map->probe function.
532  * The default ->probe function will call modprobe, which is
533  * pointless as this module is already loaded.
534  */
535 static struct kobject *sd_default_probe(dev_t devt, int *partno, void *data)
536 {
537 	return NULL;
538 }
539 
540 /*
541  * Device no to disk mapping:
542  *
543  *       major         disc2     disc  p1
544  *   |............|.............|....|....| <- dev_t
545  *    31        20 19          8 7  4 3  0
546  *
547  * Inside a major, we have 16k disks, however mapped non-
548  * contiguously. The first 16 disks are for major0, the next
549  * ones with major1, ... Disk 256 is for major0 again, disk 272
550  * for major1, ...
551  * As we stay compatible with our numbering scheme, we can reuse
552  * the well-know SCSI majors 8, 65--71, 136--143.
553  */
554 static int sd_major(int major_idx)
555 {
556 	switch (major_idx) {
557 	case 0:
558 		return SCSI_DISK0_MAJOR;
559 	case 1 ... 7:
560 		return SCSI_DISK1_MAJOR + major_idx - 1;
561 	case 8 ... 15:
562 		return SCSI_DISK8_MAJOR + major_idx - 8;
563 	default:
564 		BUG();
565 		return 0;	/* shut up gcc */
566 	}
567 }
568 
569 static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
570 {
571 	struct scsi_disk *sdkp = NULL;
572 
573 	mutex_lock(&sd_ref_mutex);
574 
575 	if (disk->private_data) {
576 		sdkp = scsi_disk(disk);
577 		if (scsi_device_get(sdkp->device) == 0)
578 			get_device(&sdkp->dev);
579 		else
580 			sdkp = NULL;
581 	}
582 	mutex_unlock(&sd_ref_mutex);
583 	return sdkp;
584 }
585 
586 static void scsi_disk_put(struct scsi_disk *sdkp)
587 {
588 	struct scsi_device *sdev = sdkp->device;
589 
590 	mutex_lock(&sd_ref_mutex);
591 	put_device(&sdkp->dev);
592 	scsi_device_put(sdev);
593 	mutex_unlock(&sd_ref_mutex);
594 }
595 
596 static unsigned char sd_setup_protect_cmnd(struct scsi_cmnd *scmd,
597 					   unsigned int dix, unsigned int dif)
598 {
599 	struct bio *bio = scmd->request->bio;
600 	unsigned int prot_op = sd_prot_op(rq_data_dir(scmd->request), dix, dif);
601 	unsigned int protect = 0;
602 
603 	if (dix) {				/* DIX Type 0, 1, 2, 3 */
604 		if (bio_integrity_flagged(bio, BIP_IP_CHECKSUM))
605 			scmd->prot_flags |= SCSI_PROT_IP_CHECKSUM;
606 
607 		if (bio_integrity_flagged(bio, BIP_CTRL_NOCHECK) == false)
608 			scmd->prot_flags |= SCSI_PROT_GUARD_CHECK;
609 	}
610 
611 	if (dif != SD_DIF_TYPE3_PROTECTION) {	/* DIX/DIF Type 0, 1, 2 */
612 		scmd->prot_flags |= SCSI_PROT_REF_INCREMENT;
613 
614 		if (bio_integrity_flagged(bio, BIP_CTRL_NOCHECK) == false)
615 			scmd->prot_flags |= SCSI_PROT_REF_CHECK;
616 	}
617 
618 	if (dif) {				/* DIX/DIF Type 1, 2, 3 */
619 		scmd->prot_flags |= SCSI_PROT_TRANSFER_PI;
620 
621 		if (bio_integrity_flagged(bio, BIP_DISK_NOCHECK))
622 			protect = 3 << 5;	/* Disable target PI checking */
623 		else
624 			protect = 1 << 5;	/* Enable target PI checking */
625 	}
626 
627 	scsi_set_prot_op(scmd, prot_op);
628 	scsi_set_prot_type(scmd, dif);
629 	scmd->prot_flags &= sd_prot_flag_mask(prot_op);
630 
631 	return protect;
632 }
633 
634 static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
635 {
636 	struct request_queue *q = sdkp->disk->queue;
637 	unsigned int logical_block_size = sdkp->device->sector_size;
638 	unsigned int max_blocks = 0;
639 
640 	q->limits.discard_zeroes_data = 0;
641 	q->limits.discard_alignment = sdkp->unmap_alignment *
642 		logical_block_size;
643 	q->limits.discard_granularity =
644 		max(sdkp->physical_block_size,
645 		    sdkp->unmap_granularity * logical_block_size);
646 
647 	sdkp->provisioning_mode = mode;
648 
649 	switch (mode) {
650 
651 	case SD_LBP_DISABLE:
652 		blk_queue_max_discard_sectors(q, 0);
653 		queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
654 		return;
655 
656 	case SD_LBP_UNMAP:
657 		max_blocks = min_not_zero(sdkp->max_unmap_blocks,
658 					  (u32)SD_MAX_WS16_BLOCKS);
659 		break;
660 
661 	case SD_LBP_WS16:
662 		max_blocks = min_not_zero(sdkp->max_ws_blocks,
663 					  (u32)SD_MAX_WS16_BLOCKS);
664 		q->limits.discard_zeroes_data = sdkp->lbprz;
665 		break;
666 
667 	case SD_LBP_WS10:
668 		max_blocks = min_not_zero(sdkp->max_ws_blocks,
669 					  (u32)SD_MAX_WS10_BLOCKS);
670 		q->limits.discard_zeroes_data = sdkp->lbprz;
671 		break;
672 
673 	case SD_LBP_ZERO:
674 		max_blocks = min_not_zero(sdkp->max_ws_blocks,
675 					  (u32)SD_MAX_WS10_BLOCKS);
676 		q->limits.discard_zeroes_data = 1;
677 		break;
678 	}
679 
680 	blk_queue_max_discard_sectors(q, max_blocks * (logical_block_size >> 9));
681 	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
682 }
683 
684 /**
685  * sd_setup_discard_cmnd - unmap blocks on thinly provisioned device
686  * @sdp: scsi device to operate one
687  * @rq: Request to prepare
688  *
689  * Will issue either UNMAP or WRITE SAME(16) depending on preference
690  * indicated by target device.
691  **/
692 static int sd_setup_discard_cmnd(struct scsi_cmnd *cmd)
693 {
694 	struct request *rq = cmd->request;
695 	struct scsi_device *sdp = cmd->device;
696 	struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
697 	sector_t sector = blk_rq_pos(rq);
698 	unsigned int nr_sectors = blk_rq_sectors(rq);
699 	unsigned int nr_bytes = blk_rq_bytes(rq);
700 	unsigned int len;
701 	int ret;
702 	char *buf;
703 	struct page *page;
704 
705 	sector >>= ilog2(sdp->sector_size) - 9;
706 	nr_sectors >>= ilog2(sdp->sector_size) - 9;
707 
708 	page = alloc_page(GFP_ATOMIC | __GFP_ZERO);
709 	if (!page)
710 		return BLKPREP_DEFER;
711 
712 	switch (sdkp->provisioning_mode) {
713 	case SD_LBP_UNMAP:
714 		buf = page_address(page);
715 
716 		cmd->cmd_len = 10;
717 		cmd->cmnd[0] = UNMAP;
718 		cmd->cmnd[8] = 24;
719 
720 		put_unaligned_be16(6 + 16, &buf[0]);
721 		put_unaligned_be16(16, &buf[2]);
722 		put_unaligned_be64(sector, &buf[8]);
723 		put_unaligned_be32(nr_sectors, &buf[16]);
724 
725 		len = 24;
726 		break;
727 
728 	case SD_LBP_WS16:
729 		cmd->cmd_len = 16;
730 		cmd->cmnd[0] = WRITE_SAME_16;
731 		cmd->cmnd[1] = 0x8; /* UNMAP */
732 		put_unaligned_be64(sector, &cmd->cmnd[2]);
733 		put_unaligned_be32(nr_sectors, &cmd->cmnd[10]);
734 
735 		len = sdkp->device->sector_size;
736 		break;
737 
738 	case SD_LBP_WS10:
739 	case SD_LBP_ZERO:
740 		cmd->cmd_len = 10;
741 		cmd->cmnd[0] = WRITE_SAME;
742 		if (sdkp->provisioning_mode == SD_LBP_WS10)
743 			cmd->cmnd[1] = 0x8; /* UNMAP */
744 		put_unaligned_be32(sector, &cmd->cmnd[2]);
745 		put_unaligned_be16(nr_sectors, &cmd->cmnd[7]);
746 
747 		len = sdkp->device->sector_size;
748 		break;
749 
750 	default:
751 		ret = BLKPREP_KILL;
752 		goto out;
753 	}
754 
755 	rq->completion_data = page;
756 	rq->timeout = SD_TIMEOUT;
757 
758 	cmd->transfersize = len;
759 	cmd->allowed = SD_MAX_RETRIES;
760 
761 	/*
762 	 * Initially __data_len is set to the amount of data that needs to be
763 	 * transferred to the target. This amount depends on whether WRITE SAME
764 	 * or UNMAP is being used. After the scatterlist has been mapped by
765 	 * scsi_init_io() we set __data_len to the size of the area to be
766 	 * discarded on disk. This allows us to report completion on the full
767 	 * amount of blocks described by the request.
768 	 */
769 	blk_add_request_payload(rq, page, len);
770 	ret = scsi_init_io(cmd);
771 	rq->__data_len = nr_bytes;
772 
773 out:
774 	if (ret != BLKPREP_OK)
775 		__free_page(page);
776 	return ret;
777 }
778 
779 static void sd_config_write_same(struct scsi_disk *sdkp)
780 {
781 	struct request_queue *q = sdkp->disk->queue;
782 	unsigned int logical_block_size = sdkp->device->sector_size;
783 
784 	if (sdkp->device->no_write_same) {
785 		sdkp->max_ws_blocks = 0;
786 		goto out;
787 	}
788 
789 	/* Some devices can not handle block counts above 0xffff despite
790 	 * supporting WRITE SAME(16). Consequently we default to 64k
791 	 * blocks per I/O unless the device explicitly advertises a
792 	 * bigger limit.
793 	 */
794 	if (sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS)
795 		sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
796 						   (u32)SD_MAX_WS16_BLOCKS);
797 	else if (sdkp->ws16 || sdkp->ws10 || sdkp->device->no_report_opcodes)
798 		sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks,
799 						   (u32)SD_MAX_WS10_BLOCKS);
800 	else {
801 		sdkp->device->no_write_same = 1;
802 		sdkp->max_ws_blocks = 0;
803 	}
804 
805 out:
806 	blk_queue_max_write_same_sectors(q, sdkp->max_ws_blocks *
807 					 (logical_block_size >> 9));
808 }
809 
810 /**
811  * sd_setup_write_same_cmnd - write the same data to multiple blocks
812  * @cmd: command to prepare
813  *
814  * Will issue either WRITE SAME(10) or WRITE SAME(16) depending on
815  * preference indicated by target device.
816  **/
817 static int sd_setup_write_same_cmnd(struct scsi_cmnd *cmd)
818 {
819 	struct request *rq = cmd->request;
820 	struct scsi_device *sdp = cmd->device;
821 	struct scsi_disk *sdkp = scsi_disk(rq->rq_disk);
822 	struct bio *bio = rq->bio;
823 	sector_t sector = blk_rq_pos(rq);
824 	unsigned int nr_sectors = blk_rq_sectors(rq);
825 	unsigned int nr_bytes = blk_rq_bytes(rq);
826 	int ret;
827 
828 	if (sdkp->device->no_write_same)
829 		return BLKPREP_KILL;
830 
831 	BUG_ON(bio_offset(bio) || bio_iovec(bio).bv_len != sdp->sector_size);
832 
833 	sector >>= ilog2(sdp->sector_size) - 9;
834 	nr_sectors >>= ilog2(sdp->sector_size) - 9;
835 
836 	rq->timeout = SD_WRITE_SAME_TIMEOUT;
837 
838 	if (sdkp->ws16 || sector > 0xffffffff || nr_sectors > 0xffff) {
839 		cmd->cmd_len = 16;
840 		cmd->cmnd[0] = WRITE_SAME_16;
841 		put_unaligned_be64(sector, &cmd->cmnd[2]);
842 		put_unaligned_be32(nr_sectors, &cmd->cmnd[10]);
843 	} else {
844 		cmd->cmd_len = 10;
845 		cmd->cmnd[0] = WRITE_SAME;
846 		put_unaligned_be32(sector, &cmd->cmnd[2]);
847 		put_unaligned_be16(nr_sectors, &cmd->cmnd[7]);
848 	}
849 
850 	cmd->transfersize = sdp->sector_size;
851 	cmd->allowed = SD_MAX_RETRIES;
852 
853 	/*
854 	 * For WRITE_SAME the data transferred in the DATA IN buffer is
855 	 * different from the amount of data actually written to the target.
856 	 *
857 	 * We set up __data_len to the amount of data transferred from the
858 	 * DATA IN buffer so that blk_rq_map_sg set up the proper S/G list
859 	 * to transfer a single sector of data first, but then reset it to
860 	 * the amount of data to be written right after so that the I/O path
861 	 * knows how much to actually write.
862 	 */
863 	rq->__data_len = sdp->sector_size;
864 	ret = scsi_init_io(cmd);
865 	rq->__data_len = nr_bytes;
866 	return ret;
867 }
868 
869 static int sd_setup_flush_cmnd(struct scsi_cmnd *cmd)
870 {
871 	struct request *rq = cmd->request;
872 
873 	/* flush requests don't perform I/O, zero the S/G table */
874 	memset(&cmd->sdb, 0, sizeof(cmd->sdb));
875 
876 	cmd->cmnd[0] = SYNCHRONIZE_CACHE;
877 	cmd->cmd_len = 10;
878 	cmd->transfersize = 0;
879 	cmd->allowed = SD_MAX_RETRIES;
880 
881 	rq->timeout = rq->q->rq_timeout * SD_FLUSH_TIMEOUT_MULTIPLIER;
882 	return BLKPREP_OK;
883 }
884 
885 static int sd_setup_read_write_cmnd(struct scsi_cmnd *SCpnt)
886 {
887 	struct request *rq = SCpnt->request;
888 	struct scsi_device *sdp = SCpnt->device;
889 	struct gendisk *disk = rq->rq_disk;
890 	struct scsi_disk *sdkp;
891 	sector_t block = blk_rq_pos(rq);
892 	sector_t threshold;
893 	unsigned int this_count = blk_rq_sectors(rq);
894 	unsigned int dif, dix;
895 	int ret;
896 	unsigned char protect;
897 
898 	ret = scsi_init_io(SCpnt);
899 	if (ret != BLKPREP_OK)
900 		goto out;
901 	SCpnt = rq->special;
902 	sdkp = scsi_disk(disk);
903 
904 	/* from here on until we're complete, any goto out
905 	 * is used for a killable error condition */
906 	ret = BLKPREP_KILL;
907 
908 	SCSI_LOG_HLQUEUE(1,
909 		scmd_printk(KERN_INFO, SCpnt,
910 			"%s: block=%llu, count=%d\n",
911 			__func__, (unsigned long long)block, this_count));
912 
913 	if (!sdp || !scsi_device_online(sdp) ||
914 	    block + blk_rq_sectors(rq) > get_capacity(disk)) {
915 		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
916 						"Finishing %u sectors\n",
917 						blk_rq_sectors(rq)));
918 		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
919 						"Retry with 0x%p\n", SCpnt));
920 		goto out;
921 	}
922 
923 	if (sdp->changed) {
924 		/*
925 		 * quietly refuse to do anything to a changed disc until
926 		 * the changed bit has been reset
927 		 */
928 		/* printk("SCSI disk has been changed or is not present. Prohibiting further I/O.\n"); */
929 		goto out;
930 	}
931 
932 	/*
933 	 * Some SD card readers can't handle multi-sector accesses which touch
934 	 * the last one or two hardware sectors.  Split accesses as needed.
935 	 */
936 	threshold = get_capacity(disk) - SD_LAST_BUGGY_SECTORS *
937 		(sdp->sector_size / 512);
938 
939 	if (unlikely(sdp->last_sector_bug && block + this_count > threshold)) {
940 		if (block < threshold) {
941 			/* Access up to the threshold but not beyond */
942 			this_count = threshold - block;
943 		} else {
944 			/* Access only a single hardware sector */
945 			this_count = sdp->sector_size / 512;
946 		}
947 	}
948 
949 	SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
950 					(unsigned long long)block));
951 
952 	/*
953 	 * If we have a 1K hardware sectorsize, prevent access to single
954 	 * 512 byte sectors.  In theory we could handle this - in fact
955 	 * the scsi cdrom driver must be able to handle this because
956 	 * we typically use 1K blocksizes, and cdroms typically have
957 	 * 2K hardware sectorsizes.  Of course, things are simpler
958 	 * with the cdrom, since it is read-only.  For performance
959 	 * reasons, the filesystems should be able to handle this
960 	 * and not force the scsi disk driver to use bounce buffers
961 	 * for this.
962 	 */
963 	if (sdp->sector_size == 1024) {
964 		if ((block & 1) || (blk_rq_sectors(rq) & 1)) {
965 			scmd_printk(KERN_ERR, SCpnt,
966 				    "Bad block number requested\n");
967 			goto out;
968 		} else {
969 			block = block >> 1;
970 			this_count = this_count >> 1;
971 		}
972 	}
973 	if (sdp->sector_size == 2048) {
974 		if ((block & 3) || (blk_rq_sectors(rq) & 3)) {
975 			scmd_printk(KERN_ERR, SCpnt,
976 				    "Bad block number requested\n");
977 			goto out;
978 		} else {
979 			block = block >> 2;
980 			this_count = this_count >> 2;
981 		}
982 	}
983 	if (sdp->sector_size == 4096) {
984 		if ((block & 7) || (blk_rq_sectors(rq) & 7)) {
985 			scmd_printk(KERN_ERR, SCpnt,
986 				    "Bad block number requested\n");
987 			goto out;
988 		} else {
989 			block = block >> 3;
990 			this_count = this_count >> 3;
991 		}
992 	}
993 	if (rq_data_dir(rq) == WRITE) {
994 		SCpnt->cmnd[0] = WRITE_6;
995 
996 		if (blk_integrity_rq(rq))
997 			sd_dif_prepare(SCpnt);
998 
999 	} else if (rq_data_dir(rq) == READ) {
1000 		SCpnt->cmnd[0] = READ_6;
1001 	} else {
1002 		scmd_printk(KERN_ERR, SCpnt, "Unknown command %llx\n", (unsigned long long) rq->cmd_flags);
1003 		goto out;
1004 	}
1005 
1006 	SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
1007 					"%s %d/%u 512 byte blocks.\n",
1008 					(rq_data_dir(rq) == WRITE) ?
1009 					"writing" : "reading", this_count,
1010 					blk_rq_sectors(rq)));
1011 
1012 	dix = scsi_prot_sg_count(SCpnt);
1013 	dif = scsi_host_dif_capable(SCpnt->device->host, sdkp->protection_type);
1014 
1015 	if (dif || dix)
1016 		protect = sd_setup_protect_cmnd(SCpnt, dix, dif);
1017 	else
1018 		protect = 0;
1019 
1020 	if (protect && sdkp->protection_type == SD_DIF_TYPE2_PROTECTION) {
1021 		SCpnt->cmnd = mempool_alloc(sd_cdb_pool, GFP_ATOMIC);
1022 
1023 		if (unlikely(SCpnt->cmnd == NULL)) {
1024 			ret = BLKPREP_DEFER;
1025 			goto out;
1026 		}
1027 
1028 		SCpnt->cmd_len = SD_EXT_CDB_SIZE;
1029 		memset(SCpnt->cmnd, 0, SCpnt->cmd_len);
1030 		SCpnt->cmnd[0] = VARIABLE_LENGTH_CMD;
1031 		SCpnt->cmnd[7] = 0x18;
1032 		SCpnt->cmnd[9] = (rq_data_dir(rq) == READ) ? READ_32 : WRITE_32;
1033 		SCpnt->cmnd[10] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
1034 
1035 		/* LBA */
1036 		SCpnt->cmnd[12] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
1037 		SCpnt->cmnd[13] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
1038 		SCpnt->cmnd[14] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
1039 		SCpnt->cmnd[15] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
1040 		SCpnt->cmnd[16] = (unsigned char) (block >> 24) & 0xff;
1041 		SCpnt->cmnd[17] = (unsigned char) (block >> 16) & 0xff;
1042 		SCpnt->cmnd[18] = (unsigned char) (block >> 8) & 0xff;
1043 		SCpnt->cmnd[19] = (unsigned char) block & 0xff;
1044 
1045 		/* Expected Indirect LBA */
1046 		SCpnt->cmnd[20] = (unsigned char) (block >> 24) & 0xff;
1047 		SCpnt->cmnd[21] = (unsigned char) (block >> 16) & 0xff;
1048 		SCpnt->cmnd[22] = (unsigned char) (block >> 8) & 0xff;
1049 		SCpnt->cmnd[23] = (unsigned char) block & 0xff;
1050 
1051 		/* Transfer length */
1052 		SCpnt->cmnd[28] = (unsigned char) (this_count >> 24) & 0xff;
1053 		SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
1054 		SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
1055 		SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
1056 	} else if (sdp->use_16_for_rw || (this_count > 0xffff)) {
1057 		SCpnt->cmnd[0] += READ_16 - READ_6;
1058 		SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
1059 		SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
1060 		SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
1061 		SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
1062 		SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
1063 		SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
1064 		SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
1065 		SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
1066 		SCpnt->cmnd[9] = (unsigned char) block & 0xff;
1067 		SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
1068 		SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
1069 		SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
1070 		SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
1071 		SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
1072 	} else if ((this_count > 0xff) || (block > 0x1fffff) ||
1073 		   scsi_device_protection(SCpnt->device) ||
1074 		   SCpnt->device->use_10_for_rw) {
1075 		SCpnt->cmnd[0] += READ_10 - READ_6;
1076 		SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
1077 		SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
1078 		SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
1079 		SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
1080 		SCpnt->cmnd[5] = (unsigned char) block & 0xff;
1081 		SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
1082 		SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
1083 		SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
1084 	} else {
1085 		if (unlikely(rq->cmd_flags & REQ_FUA)) {
1086 			/*
1087 			 * This happens only if this drive failed
1088 			 * 10byte rw command with ILLEGAL_REQUEST
1089 			 * during operation and thus turned off
1090 			 * use_10_for_rw.
1091 			 */
1092 			scmd_printk(KERN_ERR, SCpnt,
1093 				    "FUA write on READ/WRITE(6) drive\n");
1094 			goto out;
1095 		}
1096 
1097 		SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
1098 		SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
1099 		SCpnt->cmnd[3] = (unsigned char) block & 0xff;
1100 		SCpnt->cmnd[4] = (unsigned char) this_count;
1101 		SCpnt->cmnd[5] = 0;
1102 	}
1103 	SCpnt->sdb.length = this_count * sdp->sector_size;
1104 
1105 	/*
1106 	 * We shouldn't disconnect in the middle of a sector, so with a dumb
1107 	 * host adapter, it's safe to assume that we can at least transfer
1108 	 * this many bytes between each connect / disconnect.
1109 	 */
1110 	SCpnt->transfersize = sdp->sector_size;
1111 	SCpnt->underflow = this_count << 9;
1112 	SCpnt->allowed = SD_MAX_RETRIES;
1113 
1114 	/*
1115 	 * This indicates that the command is ready from our end to be
1116 	 * queued.
1117 	 */
1118 	ret = BLKPREP_OK;
1119  out:
1120 	return ret;
1121 }
1122 
1123 static int sd_init_command(struct scsi_cmnd *cmd)
1124 {
1125 	struct request *rq = cmd->request;
1126 
1127 	if (rq->cmd_flags & REQ_DISCARD)
1128 		return sd_setup_discard_cmnd(cmd);
1129 	else if (rq->cmd_flags & REQ_WRITE_SAME)
1130 		return sd_setup_write_same_cmnd(cmd);
1131 	else if (rq->cmd_flags & REQ_FLUSH)
1132 		return sd_setup_flush_cmnd(cmd);
1133 	else
1134 		return sd_setup_read_write_cmnd(cmd);
1135 }
1136 
1137 static void sd_uninit_command(struct scsi_cmnd *SCpnt)
1138 {
1139 	struct request *rq = SCpnt->request;
1140 
1141 	if (rq->cmd_flags & REQ_DISCARD)
1142 		__free_page(rq->completion_data);
1143 
1144 	if (SCpnt->cmnd != rq->cmd) {
1145 		mempool_free(SCpnt->cmnd, sd_cdb_pool);
1146 		SCpnt->cmnd = NULL;
1147 		SCpnt->cmd_len = 0;
1148 	}
1149 }
1150 
1151 /**
1152  *	sd_open - open a scsi disk device
1153  *	@inode: only i_rdev member may be used
1154  *	@filp: only f_mode and f_flags may be used
1155  *
1156  *	Returns 0 if successful. Returns a negated errno value in case
1157  *	of error.
1158  *
1159  *	Note: This can be called from a user context (e.g. fsck(1) )
1160  *	or from within the kernel (e.g. as a result of a mount(1) ).
1161  *	In the latter case @inode and @filp carry an abridged amount
1162  *	of information as noted above.
1163  *
1164  *	Locking: called with bdev->bd_mutex held.
1165  **/
1166 static int sd_open(struct block_device *bdev, fmode_t mode)
1167 {
1168 	struct scsi_disk *sdkp = scsi_disk_get(bdev->bd_disk);
1169 	struct scsi_device *sdev;
1170 	int retval;
1171 
1172 	if (!sdkp)
1173 		return -ENXIO;
1174 
1175 	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
1176 
1177 	sdev = sdkp->device;
1178 
1179 	/*
1180 	 * If the device is in error recovery, wait until it is done.
1181 	 * If the device is offline, then disallow any access to it.
1182 	 */
1183 	retval = -ENXIO;
1184 	if (!scsi_block_when_processing_errors(sdev))
1185 		goto error_out;
1186 
1187 	if (sdev->removable || sdkp->write_prot)
1188 		check_disk_change(bdev);
1189 
1190 	/*
1191 	 * If the drive is empty, just let the open fail.
1192 	 */
1193 	retval = -ENOMEDIUM;
1194 	if (sdev->removable && !sdkp->media_present && !(mode & FMODE_NDELAY))
1195 		goto error_out;
1196 
1197 	/*
1198 	 * If the device has the write protect tab set, have the open fail
1199 	 * if the user expects to be able to write to the thing.
1200 	 */
1201 	retval = -EROFS;
1202 	if (sdkp->write_prot && (mode & FMODE_WRITE))
1203 		goto error_out;
1204 
1205 	/*
1206 	 * It is possible that the disk changing stuff resulted in
1207 	 * the device being taken offline.  If this is the case,
1208 	 * report this to the user, and don't pretend that the
1209 	 * open actually succeeded.
1210 	 */
1211 	retval = -ENXIO;
1212 	if (!scsi_device_online(sdev))
1213 		goto error_out;
1214 
1215 	if ((atomic_inc_return(&sdkp->openers) == 1) && sdev->removable) {
1216 		if (scsi_block_when_processing_errors(sdev))
1217 			scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
1218 	}
1219 
1220 	return 0;
1221 
1222 error_out:
1223 	scsi_disk_put(sdkp);
1224 	return retval;
1225 }
1226 
1227 /**
1228  *	sd_release - invoked when the (last) close(2) is called on this
1229  *	scsi disk.
1230  *	@inode: only i_rdev member may be used
1231  *	@filp: only f_mode and f_flags may be used
1232  *
1233  *	Returns 0.
1234  *
1235  *	Note: may block (uninterruptible) if error recovery is underway
1236  *	on this disk.
1237  *
1238  *	Locking: called with bdev->bd_mutex held.
1239  **/
1240 static void sd_release(struct gendisk *disk, fmode_t mode)
1241 {
1242 	struct scsi_disk *sdkp = scsi_disk(disk);
1243 	struct scsi_device *sdev = sdkp->device;
1244 
1245 	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
1246 
1247 	if (atomic_dec_return(&sdkp->openers) == 0 && sdev->removable) {
1248 		if (scsi_block_when_processing_errors(sdev))
1249 			scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
1250 	}
1251 
1252 	/*
1253 	 * XXX and what if there are packets in flight and this close()
1254 	 * XXX is followed by a "rmmod sd_mod"?
1255 	 */
1256 
1257 	scsi_disk_put(sdkp);
1258 }
1259 
1260 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
1261 {
1262 	struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
1263 	struct scsi_device *sdp = sdkp->device;
1264 	struct Scsi_Host *host = sdp->host;
1265 	int diskinfo[4];
1266 
1267 	/* default to most commonly used values */
1268         diskinfo[0] = 0x40;	/* 1 << 6 */
1269        	diskinfo[1] = 0x20;	/* 1 << 5 */
1270        	diskinfo[2] = sdkp->capacity >> 11;
1271 
1272 	/* override with calculated, extended default, or driver values */
1273 	if (host->hostt->bios_param)
1274 		host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
1275 	else
1276 		scsicam_bios_param(bdev, sdkp->capacity, diskinfo);
1277 
1278 	geo->heads = diskinfo[0];
1279 	geo->sectors = diskinfo[1];
1280 	geo->cylinders = diskinfo[2];
1281 	return 0;
1282 }
1283 
1284 /**
1285  *	sd_ioctl - process an ioctl
1286  *	@inode: only i_rdev/i_bdev members may be used
1287  *	@filp: only f_mode and f_flags may be used
1288  *	@cmd: ioctl command number
1289  *	@arg: this is third argument given to ioctl(2) system call.
1290  *	Often contains a pointer.
1291  *
1292  *	Returns 0 if successful (some ioctls return positive numbers on
1293  *	success as well). Returns a negated errno value in case of error.
1294  *
1295  *	Note: most ioctls are forward onto the block subsystem or further
1296  *	down in the scsi subsystem.
1297  **/
1298 static int sd_ioctl(struct block_device *bdev, fmode_t mode,
1299 		    unsigned int cmd, unsigned long arg)
1300 {
1301 	struct gendisk *disk = bdev->bd_disk;
1302 	struct scsi_disk *sdkp = scsi_disk(disk);
1303 	struct scsi_device *sdp = sdkp->device;
1304 	void __user *p = (void __user *)arg;
1305 	int error;
1306 
1307 	SCSI_LOG_IOCTL(1, sd_printk(KERN_INFO, sdkp, "sd_ioctl: disk=%s, "
1308 				    "cmd=0x%x\n", disk->disk_name, cmd));
1309 
1310 	error = scsi_verify_blk_ioctl(bdev, cmd);
1311 	if (error < 0)
1312 		return error;
1313 
1314 	/*
1315 	 * If we are in the middle of error recovery, don't let anyone
1316 	 * else try and use this device.  Also, if error recovery fails, it
1317 	 * may try and take the device offline, in which case all further
1318 	 * access to the device is prohibited.
1319 	 */
1320 	error = scsi_ioctl_block_when_processing_errors(sdp, cmd,
1321 			(mode & FMODE_NDELAY) != 0);
1322 	if (error)
1323 		goto out;
1324 
1325 	/*
1326 	 * Send SCSI addressing ioctls directly to mid level, send other
1327 	 * ioctls to block level and then onto mid level if they can't be
1328 	 * resolved.
1329 	 */
1330 	switch (cmd) {
1331 		case SCSI_IOCTL_GET_IDLUN:
1332 		case SCSI_IOCTL_GET_BUS_NUMBER:
1333 			error = scsi_ioctl(sdp, cmd, p);
1334 			break;
1335 		default:
1336 			error = scsi_cmd_blk_ioctl(bdev, mode, cmd, p);
1337 			if (error != -ENOTTY)
1338 				break;
1339 			error = scsi_ioctl(sdp, cmd, p);
1340 			break;
1341 	}
1342 out:
1343 	return error;
1344 }
1345 
1346 static void set_media_not_present(struct scsi_disk *sdkp)
1347 {
1348 	if (sdkp->media_present)
1349 		sdkp->device->changed = 1;
1350 
1351 	if (sdkp->device->removable) {
1352 		sdkp->media_present = 0;
1353 		sdkp->capacity = 0;
1354 	}
1355 }
1356 
1357 static int media_not_present(struct scsi_disk *sdkp,
1358 			     struct scsi_sense_hdr *sshdr)
1359 {
1360 	if (!scsi_sense_valid(sshdr))
1361 		return 0;
1362 
1363 	/* not invoked for commands that could return deferred errors */
1364 	switch (sshdr->sense_key) {
1365 	case UNIT_ATTENTION:
1366 	case NOT_READY:
1367 		/* medium not present */
1368 		if (sshdr->asc == 0x3A) {
1369 			set_media_not_present(sdkp);
1370 			return 1;
1371 		}
1372 	}
1373 	return 0;
1374 }
1375 
1376 /**
1377  *	sd_check_events - check media events
1378  *	@disk: kernel device descriptor
1379  *	@clearing: disk events currently being cleared
1380  *
1381  *	Returns mask of DISK_EVENT_*.
1382  *
1383  *	Note: this function is invoked from the block subsystem.
1384  **/
1385 static unsigned int sd_check_events(struct gendisk *disk, unsigned int clearing)
1386 {
1387 	struct scsi_disk *sdkp = scsi_disk(disk);
1388 	struct scsi_device *sdp = sdkp->device;
1389 	struct scsi_sense_hdr *sshdr = NULL;
1390 	int retval;
1391 
1392 	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_check_events\n"));
1393 
1394 	/*
1395 	 * If the device is offline, don't send any commands - just pretend as
1396 	 * if the command failed.  If the device ever comes back online, we
1397 	 * can deal with it then.  It is only because of unrecoverable errors
1398 	 * that we would ever take a device offline in the first place.
1399 	 */
1400 	if (!scsi_device_online(sdp)) {
1401 		set_media_not_present(sdkp);
1402 		goto out;
1403 	}
1404 
1405 	/*
1406 	 * Using TEST_UNIT_READY enables differentiation between drive with
1407 	 * no cartridge loaded - NOT READY, drive with changed cartridge -
1408 	 * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
1409 	 *
1410 	 * Drives that auto spin down. eg iomega jaz 1G, will be started
1411 	 * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
1412 	 * sd_revalidate() is called.
1413 	 */
1414 	retval = -ENODEV;
1415 
1416 	if (scsi_block_when_processing_errors(sdp)) {
1417 		sshdr  = kzalloc(sizeof(*sshdr), GFP_KERNEL);
1418 		retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES,
1419 					      sshdr);
1420 	}
1421 
1422 	/* failed to execute TUR, assume media not present */
1423 	if (host_byte(retval)) {
1424 		set_media_not_present(sdkp);
1425 		goto out;
1426 	}
1427 
1428 	if (media_not_present(sdkp, sshdr))
1429 		goto out;
1430 
1431 	/*
1432 	 * For removable scsi disk we have to recognise the presence
1433 	 * of a disk in the drive.
1434 	 */
1435 	if (!sdkp->media_present)
1436 		sdp->changed = 1;
1437 	sdkp->media_present = 1;
1438 out:
1439 	/*
1440 	 * sdp->changed is set under the following conditions:
1441 	 *
1442 	 *	Medium present state has changed in either direction.
1443 	 *	Device has indicated UNIT_ATTENTION.
1444 	 */
1445 	kfree(sshdr);
1446 	retval = sdp->changed ? DISK_EVENT_MEDIA_CHANGE : 0;
1447 	sdp->changed = 0;
1448 	return retval;
1449 }
1450 
1451 static int sd_sync_cache(struct scsi_disk *sdkp)
1452 {
1453 	int retries, res;
1454 	struct scsi_device *sdp = sdkp->device;
1455 	const int timeout = sdp->request_queue->rq_timeout
1456 		* SD_FLUSH_TIMEOUT_MULTIPLIER;
1457 	struct scsi_sense_hdr sshdr;
1458 
1459 	if (!scsi_device_online(sdp))
1460 		return -ENODEV;
1461 
1462 	for (retries = 3; retries > 0; --retries) {
1463 		unsigned char cmd[10] = { 0 };
1464 
1465 		cmd[0] = SYNCHRONIZE_CACHE;
1466 		/*
1467 		 * Leave the rest of the command zero to indicate
1468 		 * flush everything.
1469 		 */
1470 		res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0,
1471 					     &sshdr, timeout, SD_MAX_RETRIES,
1472 					     NULL, REQ_PM);
1473 		if (res == 0)
1474 			break;
1475 	}
1476 
1477 	if (res) {
1478 		sd_print_result(sdkp, "Synchronize Cache(10) failed", res);
1479 
1480 		if (driver_byte(res) & DRIVER_SENSE)
1481 			sd_print_sense_hdr(sdkp, &sshdr);
1482 		/* we need to evaluate the error return  */
1483 		if (scsi_sense_valid(&sshdr) &&
1484 			(sshdr.asc == 0x3a ||	/* medium not present */
1485 			 sshdr.asc == 0x20))	/* invalid command */
1486 				/* this is no error here */
1487 				return 0;
1488 
1489 		switch (host_byte(res)) {
1490 		/* ignore errors due to racing a disconnection */
1491 		case DID_BAD_TARGET:
1492 		case DID_NO_CONNECT:
1493 			return 0;
1494 		/* signal the upper layer it might try again */
1495 		case DID_BUS_BUSY:
1496 		case DID_IMM_RETRY:
1497 		case DID_REQUEUE:
1498 		case DID_SOFT_ERROR:
1499 			return -EBUSY;
1500 		default:
1501 			return -EIO;
1502 		}
1503 	}
1504 	return 0;
1505 }
1506 
1507 static void sd_rescan(struct device *dev)
1508 {
1509 	struct scsi_disk *sdkp = dev_get_drvdata(dev);
1510 
1511 	revalidate_disk(sdkp->disk);
1512 }
1513 
1514 
1515 #ifdef CONFIG_COMPAT
1516 /*
1517  * This gets directly called from VFS. When the ioctl
1518  * is not recognized we go back to the other translation paths.
1519  */
1520 static int sd_compat_ioctl(struct block_device *bdev, fmode_t mode,
1521 			   unsigned int cmd, unsigned long arg)
1522 {
1523 	struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
1524 	int error;
1525 
1526 	error = scsi_ioctl_block_when_processing_errors(sdev, cmd,
1527 			(mode & FMODE_NDELAY) != 0);
1528 	if (error)
1529 		return error;
1530 
1531 	/*
1532 	 * Let the static ioctl translation table take care of it.
1533 	 */
1534 	if (!sdev->host->hostt->compat_ioctl)
1535 		return -ENOIOCTLCMD;
1536 	return sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
1537 }
1538 #endif
1539 
1540 static char sd_pr_type(enum pr_type type)
1541 {
1542 	switch (type) {
1543 	case PR_WRITE_EXCLUSIVE:
1544 		return 0x01;
1545 	case PR_EXCLUSIVE_ACCESS:
1546 		return 0x03;
1547 	case PR_WRITE_EXCLUSIVE_REG_ONLY:
1548 		return 0x05;
1549 	case PR_EXCLUSIVE_ACCESS_REG_ONLY:
1550 		return 0x06;
1551 	case PR_WRITE_EXCLUSIVE_ALL_REGS:
1552 		return 0x07;
1553 	case PR_EXCLUSIVE_ACCESS_ALL_REGS:
1554 		return 0x08;
1555 	default:
1556 		return 0;
1557 	}
1558 };
1559 
1560 static int sd_pr_command(struct block_device *bdev, u8 sa,
1561 		u64 key, u64 sa_key, u8 type, u8 flags)
1562 {
1563 	struct scsi_device *sdev = scsi_disk(bdev->bd_disk)->device;
1564 	struct scsi_sense_hdr sshdr;
1565 	int result;
1566 	u8 cmd[16] = { 0, };
1567 	u8 data[24] = { 0, };
1568 
1569 	cmd[0] = PERSISTENT_RESERVE_OUT;
1570 	cmd[1] = sa;
1571 	cmd[2] = type;
1572 	put_unaligned_be32(sizeof(data), &cmd[5]);
1573 
1574 	put_unaligned_be64(key, &data[0]);
1575 	put_unaligned_be64(sa_key, &data[8]);
1576 	data[20] = flags;
1577 
1578 	result = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, &data, sizeof(data),
1579 			&sshdr, SD_TIMEOUT, SD_MAX_RETRIES, NULL);
1580 
1581 	if ((driver_byte(result) & DRIVER_SENSE) &&
1582 	    (scsi_sense_valid(&sshdr))) {
1583 		sdev_printk(KERN_INFO, sdev, "PR command failed: %d\n", result);
1584 		scsi_print_sense_hdr(sdev, NULL, &sshdr);
1585 	}
1586 
1587 	return result;
1588 }
1589 
1590 static int sd_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
1591 		u32 flags)
1592 {
1593 	if (flags & ~PR_FL_IGNORE_KEY)
1594 		return -EOPNOTSUPP;
1595 	return sd_pr_command(bdev, (flags & PR_FL_IGNORE_KEY) ? 0x06 : 0x00,
1596 			old_key, new_key, 0,
1597 			(1 << 0) /* APTPL */ |
1598 			(1 << 2) /* ALL_TG_PT */);
1599 }
1600 
1601 static int sd_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type,
1602 		u32 flags)
1603 {
1604 	if (flags)
1605 		return -EOPNOTSUPP;
1606 	return sd_pr_command(bdev, 0x01, key, 0, sd_pr_type(type), 0);
1607 }
1608 
1609 static int sd_pr_release(struct block_device *bdev, u64 key, enum pr_type type)
1610 {
1611 	return sd_pr_command(bdev, 0x02, key, 0, sd_pr_type(type), 0);
1612 }
1613 
1614 static int sd_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key,
1615 		enum pr_type type, bool abort)
1616 {
1617 	return sd_pr_command(bdev, abort ? 0x05 : 0x04, old_key, new_key,
1618 			     sd_pr_type(type), 0);
1619 }
1620 
1621 static int sd_pr_clear(struct block_device *bdev, u64 key)
1622 {
1623 	return sd_pr_command(bdev, 0x03, key, 0, 0, 0);
1624 }
1625 
1626 static const struct pr_ops sd_pr_ops = {
1627 	.pr_register	= sd_pr_register,
1628 	.pr_reserve	= sd_pr_reserve,
1629 	.pr_release	= sd_pr_release,
1630 	.pr_preempt	= sd_pr_preempt,
1631 	.pr_clear	= sd_pr_clear,
1632 };
1633 
1634 static const struct block_device_operations sd_fops = {
1635 	.owner			= THIS_MODULE,
1636 	.open			= sd_open,
1637 	.release		= sd_release,
1638 	.ioctl			= sd_ioctl,
1639 	.getgeo			= sd_getgeo,
1640 #ifdef CONFIG_COMPAT
1641 	.compat_ioctl		= sd_compat_ioctl,
1642 #endif
1643 	.check_events		= sd_check_events,
1644 	.revalidate_disk	= sd_revalidate_disk,
1645 	.unlock_native_capacity	= sd_unlock_native_capacity,
1646 	.pr_ops			= &sd_pr_ops,
1647 };
1648 
1649 /**
1650  *	sd_eh_action - error handling callback
1651  *	@scmd:		sd-issued command that has failed
1652  *	@eh_disp:	The recovery disposition suggested by the midlayer
1653  *
1654  *	This function is called by the SCSI midlayer upon completion of an
1655  *	error test command (currently TEST UNIT READY). The result of sending
1656  *	the eh command is passed in eh_disp.  We're looking for devices that
1657  *	fail medium access commands but are OK with non access commands like
1658  *	test unit ready (so wrongly see the device as having a successful
1659  *	recovery)
1660  **/
1661 static int sd_eh_action(struct scsi_cmnd *scmd, int eh_disp)
1662 {
1663 	struct scsi_disk *sdkp = scsi_disk(scmd->request->rq_disk);
1664 
1665 	if (!scsi_device_online(scmd->device) ||
1666 	    !scsi_medium_access_command(scmd) ||
1667 	    host_byte(scmd->result) != DID_TIME_OUT ||
1668 	    eh_disp != SUCCESS)
1669 		return eh_disp;
1670 
1671 	/*
1672 	 * The device has timed out executing a medium access command.
1673 	 * However, the TEST UNIT READY command sent during error
1674 	 * handling completed successfully. Either the device is in the
1675 	 * process of recovering or has it suffered an internal failure
1676 	 * that prevents access to the storage medium.
1677 	 */
1678 	sdkp->medium_access_timed_out++;
1679 
1680 	/*
1681 	 * If the device keeps failing read/write commands but TEST UNIT
1682 	 * READY always completes successfully we assume that medium
1683 	 * access is no longer possible and take the device offline.
1684 	 */
1685 	if (sdkp->medium_access_timed_out >= sdkp->max_medium_access_timeouts) {
1686 		scmd_printk(KERN_ERR, scmd,
1687 			    "Medium access timeout failure. Offlining disk!\n");
1688 		scsi_device_set_state(scmd->device, SDEV_OFFLINE);
1689 
1690 		return FAILED;
1691 	}
1692 
1693 	return eh_disp;
1694 }
1695 
1696 static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
1697 {
1698 	u64 start_lba = blk_rq_pos(scmd->request);
1699 	u64 end_lba = blk_rq_pos(scmd->request) + (scsi_bufflen(scmd) / 512);
1700 	u64 factor = scmd->device->sector_size / 512;
1701 	u64 bad_lba;
1702 	int info_valid;
1703 	/*
1704 	 * resid is optional but mostly filled in.  When it's unused,
1705 	 * its value is zero, so we assume the whole buffer transferred
1706 	 */
1707 	unsigned int transferred = scsi_bufflen(scmd) - scsi_get_resid(scmd);
1708 	unsigned int good_bytes;
1709 
1710 	if (scmd->request->cmd_type != REQ_TYPE_FS)
1711 		return 0;
1712 
1713 	info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
1714 					     SCSI_SENSE_BUFFERSIZE,
1715 					     &bad_lba);
1716 	if (!info_valid)
1717 		return 0;
1718 
1719 	if (scsi_bufflen(scmd) <= scmd->device->sector_size)
1720 		return 0;
1721 
1722 	/* be careful ... don't want any overflows */
1723 	do_div(start_lba, factor);
1724 	do_div(end_lba, factor);
1725 
1726 	/* The bad lba was reported incorrectly, we have no idea where
1727 	 * the error is.
1728 	 */
1729 	if (bad_lba < start_lba  || bad_lba >= end_lba)
1730 		return 0;
1731 
1732 	/* This computation should always be done in terms of
1733 	 * the resolution of the device's medium.
1734 	 */
1735 	good_bytes = (bad_lba - start_lba) * scmd->device->sector_size;
1736 	return min(good_bytes, transferred);
1737 }
1738 
1739 /**
1740  *	sd_done - bottom half handler: called when the lower level
1741  *	driver has completed (successfully or otherwise) a scsi command.
1742  *	@SCpnt: mid-level's per command structure.
1743  *
1744  *	Note: potentially run from within an ISR. Must not block.
1745  **/
1746 static int sd_done(struct scsi_cmnd *SCpnt)
1747 {
1748 	int result = SCpnt->result;
1749 	unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
1750 	struct scsi_sense_hdr sshdr;
1751 	struct scsi_disk *sdkp = scsi_disk(SCpnt->request->rq_disk);
1752 	struct request *req = SCpnt->request;
1753 	int sense_valid = 0;
1754 	int sense_deferred = 0;
1755 	unsigned char op = SCpnt->cmnd[0];
1756 	unsigned char unmap = SCpnt->cmnd[1] & 8;
1757 
1758 	if (req->cmd_flags & REQ_DISCARD || req->cmd_flags & REQ_WRITE_SAME) {
1759 		if (!result) {
1760 			good_bytes = blk_rq_bytes(req);
1761 			scsi_set_resid(SCpnt, 0);
1762 		} else {
1763 			good_bytes = 0;
1764 			scsi_set_resid(SCpnt, blk_rq_bytes(req));
1765 		}
1766 	}
1767 
1768 	if (result) {
1769 		sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
1770 		if (sense_valid)
1771 			sense_deferred = scsi_sense_is_deferred(&sshdr);
1772 	}
1773 	sdkp->medium_access_timed_out = 0;
1774 
1775 	if (driver_byte(result) != DRIVER_SENSE &&
1776 	    (!sense_valid || sense_deferred))
1777 		goto out;
1778 
1779 	switch (sshdr.sense_key) {
1780 	case HARDWARE_ERROR:
1781 	case MEDIUM_ERROR:
1782 		good_bytes = sd_completed_bytes(SCpnt);
1783 		break;
1784 	case RECOVERED_ERROR:
1785 		good_bytes = scsi_bufflen(SCpnt);
1786 		break;
1787 	case NO_SENSE:
1788 		/* This indicates a false check condition, so ignore it.  An
1789 		 * unknown amount of data was transferred so treat it as an
1790 		 * error.
1791 		 */
1792 		SCpnt->result = 0;
1793 		memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
1794 		break;
1795 	case ABORTED_COMMAND:
1796 		if (sshdr.asc == 0x10)  /* DIF: Target detected corruption */
1797 			good_bytes = sd_completed_bytes(SCpnt);
1798 		break;
1799 	case ILLEGAL_REQUEST:
1800 		if (sshdr.asc == 0x10)  /* DIX: Host detected corruption */
1801 			good_bytes = sd_completed_bytes(SCpnt);
1802 		/* INVALID COMMAND OPCODE or INVALID FIELD IN CDB */
1803 		if (sshdr.asc == 0x20 || sshdr.asc == 0x24) {
1804 			switch (op) {
1805 			case UNMAP:
1806 				sd_config_discard(sdkp, SD_LBP_DISABLE);
1807 				break;
1808 			case WRITE_SAME_16:
1809 			case WRITE_SAME:
1810 				if (unmap)
1811 					sd_config_discard(sdkp, SD_LBP_DISABLE);
1812 				else {
1813 					sdkp->device->no_write_same = 1;
1814 					sd_config_write_same(sdkp);
1815 
1816 					good_bytes = 0;
1817 					req->__data_len = blk_rq_bytes(req);
1818 					req->cmd_flags |= REQ_QUIET;
1819 				}
1820 			}
1821 		}
1822 		break;
1823 	default:
1824 		break;
1825 	}
1826  out:
1827 	SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
1828 					   "sd_done: completed %d of %d bytes\n",
1829 					   good_bytes, scsi_bufflen(SCpnt)));
1830 
1831 	if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
1832 		sd_dif_complete(SCpnt, good_bytes);
1833 
1834 	return good_bytes;
1835 }
1836 
1837 /*
1838  * spinup disk - called only in sd_revalidate_disk()
1839  */
1840 static void
1841 sd_spinup_disk(struct scsi_disk *sdkp)
1842 {
1843 	unsigned char cmd[10];
1844 	unsigned long spintime_expire = 0;
1845 	int retries, spintime;
1846 	unsigned int the_result;
1847 	struct scsi_sense_hdr sshdr;
1848 	int sense_valid = 0;
1849 
1850 	spintime = 0;
1851 
1852 	/* Spin up drives, as required.  Only do this at boot time */
1853 	/* Spinup needs to be done for module loads too. */
1854 	do {
1855 		retries = 0;
1856 
1857 		do {
1858 			cmd[0] = TEST_UNIT_READY;
1859 			memset((void *) &cmd[1], 0, 9);
1860 
1861 			the_result = scsi_execute_req(sdkp->device, cmd,
1862 						      DMA_NONE, NULL, 0,
1863 						      &sshdr, SD_TIMEOUT,
1864 						      SD_MAX_RETRIES, NULL);
1865 
1866 			/*
1867 			 * If the drive has indicated to us that it
1868 			 * doesn't have any media in it, don't bother
1869 			 * with any more polling.
1870 			 */
1871 			if (media_not_present(sdkp, &sshdr))
1872 				return;
1873 
1874 			if (the_result)
1875 				sense_valid = scsi_sense_valid(&sshdr);
1876 			retries++;
1877 		} while (retries < 3 &&
1878 			 (!scsi_status_is_good(the_result) ||
1879 			  ((driver_byte(the_result) & DRIVER_SENSE) &&
1880 			  sense_valid && sshdr.sense_key == UNIT_ATTENTION)));
1881 
1882 		if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
1883 			/* no sense, TUR either succeeded or failed
1884 			 * with a status error */
1885 			if(!spintime && !scsi_status_is_good(the_result)) {
1886 				sd_print_result(sdkp, "Test Unit Ready failed",
1887 						the_result);
1888 			}
1889 			break;
1890 		}
1891 
1892 		/*
1893 		 * The device does not want the automatic start to be issued.
1894 		 */
1895 		if (sdkp->device->no_start_on_add)
1896 			break;
1897 
1898 		if (sense_valid && sshdr.sense_key == NOT_READY) {
1899 			if (sshdr.asc == 4 && sshdr.ascq == 3)
1900 				break;	/* manual intervention required */
1901 			if (sshdr.asc == 4 && sshdr.ascq == 0xb)
1902 				break;	/* standby */
1903 			if (sshdr.asc == 4 && sshdr.ascq == 0xc)
1904 				break;	/* unavailable */
1905 			/*
1906 			 * Issue command to spin up drive when not ready
1907 			 */
1908 			if (!spintime) {
1909 				sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
1910 				cmd[0] = START_STOP;
1911 				cmd[1] = 1;	/* Return immediately */
1912 				memset((void *) &cmd[2], 0, 8);
1913 				cmd[4] = 1;	/* Start spin cycle */
1914 				if (sdkp->device->start_stop_pwr_cond)
1915 					cmd[4] |= 1 << 4;
1916 				scsi_execute_req(sdkp->device, cmd, DMA_NONE,
1917 						 NULL, 0, &sshdr,
1918 						 SD_TIMEOUT, SD_MAX_RETRIES,
1919 						 NULL);
1920 				spintime_expire = jiffies + 100 * HZ;
1921 				spintime = 1;
1922 			}
1923 			/* Wait 1 second for next try */
1924 			msleep(1000);
1925 			printk(".");
1926 
1927 		/*
1928 		 * Wait for USB flash devices with slow firmware.
1929 		 * Yes, this sense key/ASC combination shouldn't
1930 		 * occur here.  It's characteristic of these devices.
1931 		 */
1932 		} else if (sense_valid &&
1933 				sshdr.sense_key == UNIT_ATTENTION &&
1934 				sshdr.asc == 0x28) {
1935 			if (!spintime) {
1936 				spintime_expire = jiffies + 5 * HZ;
1937 				spintime = 1;
1938 			}
1939 			/* Wait 1 second for next try */
1940 			msleep(1000);
1941 		} else {
1942 			/* we don't understand the sense code, so it's
1943 			 * probably pointless to loop */
1944 			if(!spintime) {
1945 				sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
1946 				sd_print_sense_hdr(sdkp, &sshdr);
1947 			}
1948 			break;
1949 		}
1950 
1951 	} while (spintime && time_before_eq(jiffies, spintime_expire));
1952 
1953 	if (spintime) {
1954 		if (scsi_status_is_good(the_result))
1955 			printk("ready\n");
1956 		else
1957 			printk("not responding...\n");
1958 	}
1959 }
1960 
1961 
1962 /*
1963  * Determine whether disk supports Data Integrity Field.
1964  */
1965 static int sd_read_protection_type(struct scsi_disk *sdkp, unsigned char *buffer)
1966 {
1967 	struct scsi_device *sdp = sdkp->device;
1968 	u8 type;
1969 	int ret = 0;
1970 
1971 	if (scsi_device_protection(sdp) == 0 || (buffer[12] & 1) == 0)
1972 		return ret;
1973 
1974 	type = ((buffer[12] >> 1) & 7) + 1; /* P_TYPE 0 = Type 1 */
1975 
1976 	if (type > SD_DIF_TYPE3_PROTECTION)
1977 		ret = -ENODEV;
1978 	else if (scsi_host_dif_capable(sdp->host, type))
1979 		ret = 1;
1980 
1981 	if (sdkp->first_scan || type != sdkp->protection_type)
1982 		switch (ret) {
1983 		case -ENODEV:
1984 			sd_printk(KERN_ERR, sdkp, "formatted with unsupported" \
1985 				  " protection type %u. Disabling disk!\n",
1986 				  type);
1987 			break;
1988 		case 1:
1989 			sd_printk(KERN_NOTICE, sdkp,
1990 				  "Enabling DIF Type %u protection\n", type);
1991 			break;
1992 		case 0:
1993 			sd_printk(KERN_NOTICE, sdkp,
1994 				  "Disabling DIF Type %u protection\n", type);
1995 			break;
1996 		}
1997 
1998 	sdkp->protection_type = type;
1999 
2000 	return ret;
2001 }
2002 
2003 static void read_capacity_error(struct scsi_disk *sdkp, struct scsi_device *sdp,
2004 			struct scsi_sense_hdr *sshdr, int sense_valid,
2005 			int the_result)
2006 {
2007 	if (driver_byte(the_result) & DRIVER_SENSE)
2008 		sd_print_sense_hdr(sdkp, sshdr);
2009 	else
2010 		sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
2011 
2012 	/*
2013 	 * Set dirty bit for removable devices if not ready -
2014 	 * sometimes drives will not report this properly.
2015 	 */
2016 	if (sdp->removable &&
2017 	    sense_valid && sshdr->sense_key == NOT_READY)
2018 		set_media_not_present(sdkp);
2019 
2020 	/*
2021 	 * We used to set media_present to 0 here to indicate no media
2022 	 * in the drive, but some drives fail read capacity even with
2023 	 * media present, so we can't do that.
2024 	 */
2025 	sdkp->capacity = 0; /* unknown mapped to zero - as usual */
2026 }
2027 
2028 #define RC16_LEN 32
2029 #if RC16_LEN > SD_BUF_SIZE
2030 #error RC16_LEN must not be more than SD_BUF_SIZE
2031 #endif
2032 
2033 #define READ_CAPACITY_RETRIES_ON_RESET	10
2034 
2035 static int read_capacity_16(struct scsi_disk *sdkp, struct scsi_device *sdp,
2036 						unsigned char *buffer)
2037 {
2038 	unsigned char cmd[16];
2039 	struct scsi_sense_hdr sshdr;
2040 	int sense_valid = 0;
2041 	int the_result;
2042 	int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
2043 	unsigned int alignment;
2044 	unsigned long long lba;
2045 	unsigned sector_size;
2046 
2047 	if (sdp->no_read_capacity_16)
2048 		return -EINVAL;
2049 
2050 	do {
2051 		memset(cmd, 0, 16);
2052 		cmd[0] = SERVICE_ACTION_IN_16;
2053 		cmd[1] = SAI_READ_CAPACITY_16;
2054 		cmd[13] = RC16_LEN;
2055 		memset(buffer, 0, RC16_LEN);
2056 
2057 		the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
2058 					buffer, RC16_LEN, &sshdr,
2059 					SD_TIMEOUT, SD_MAX_RETRIES, NULL);
2060 
2061 		if (media_not_present(sdkp, &sshdr))
2062 			return -ENODEV;
2063 
2064 		if (the_result) {
2065 			sense_valid = scsi_sense_valid(&sshdr);
2066 			if (sense_valid &&
2067 			    sshdr.sense_key == ILLEGAL_REQUEST &&
2068 			    (sshdr.asc == 0x20 || sshdr.asc == 0x24) &&
2069 			    sshdr.ascq == 0x00)
2070 				/* Invalid Command Operation Code or
2071 				 * Invalid Field in CDB, just retry
2072 				 * silently with RC10 */
2073 				return -EINVAL;
2074 			if (sense_valid &&
2075 			    sshdr.sense_key == UNIT_ATTENTION &&
2076 			    sshdr.asc == 0x29 && sshdr.ascq == 0x00)
2077 				/* Device reset might occur several times,
2078 				 * give it one more chance */
2079 				if (--reset_retries > 0)
2080 					continue;
2081 		}
2082 		retries--;
2083 
2084 	} while (the_result && retries);
2085 
2086 	if (the_result) {
2087 		sd_print_result(sdkp, "Read Capacity(16) failed", the_result);
2088 		read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
2089 		return -EINVAL;
2090 	}
2091 
2092 	sector_size = get_unaligned_be32(&buffer[8]);
2093 	lba = get_unaligned_be64(&buffer[0]);
2094 
2095 	if (sd_read_protection_type(sdkp, buffer) < 0) {
2096 		sdkp->capacity = 0;
2097 		return -ENODEV;
2098 	}
2099 
2100 	if ((sizeof(sdkp->capacity) == 4) && (lba >= 0xffffffffULL)) {
2101 		sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
2102 			"kernel compiled with support for large block "
2103 			"devices.\n");
2104 		sdkp->capacity = 0;
2105 		return -EOVERFLOW;
2106 	}
2107 
2108 	/* Logical blocks per physical block exponent */
2109 	sdkp->physical_block_size = (1 << (buffer[13] & 0xf)) * sector_size;
2110 
2111 	/* Lowest aligned logical block */
2112 	alignment = ((buffer[14] & 0x3f) << 8 | buffer[15]) * sector_size;
2113 	blk_queue_alignment_offset(sdp->request_queue, alignment);
2114 	if (alignment && sdkp->first_scan)
2115 		sd_printk(KERN_NOTICE, sdkp,
2116 			  "physical block alignment offset: %u\n", alignment);
2117 
2118 	if (buffer[14] & 0x80) { /* LBPME */
2119 		sdkp->lbpme = 1;
2120 
2121 		if (buffer[14] & 0x40) /* LBPRZ */
2122 			sdkp->lbprz = 1;
2123 
2124 		sd_config_discard(sdkp, SD_LBP_WS16);
2125 	}
2126 
2127 	sdkp->capacity = lba + 1;
2128 	return sector_size;
2129 }
2130 
2131 static int read_capacity_10(struct scsi_disk *sdkp, struct scsi_device *sdp,
2132 						unsigned char *buffer)
2133 {
2134 	unsigned char cmd[16];
2135 	struct scsi_sense_hdr sshdr;
2136 	int sense_valid = 0;
2137 	int the_result;
2138 	int retries = 3, reset_retries = READ_CAPACITY_RETRIES_ON_RESET;
2139 	sector_t lba;
2140 	unsigned sector_size;
2141 
2142 	do {
2143 		cmd[0] = READ_CAPACITY;
2144 		memset(&cmd[1], 0, 9);
2145 		memset(buffer, 0, 8);
2146 
2147 		the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
2148 					buffer, 8, &sshdr,
2149 					SD_TIMEOUT, SD_MAX_RETRIES, NULL);
2150 
2151 		if (media_not_present(sdkp, &sshdr))
2152 			return -ENODEV;
2153 
2154 		if (the_result) {
2155 			sense_valid = scsi_sense_valid(&sshdr);
2156 			if (sense_valid &&
2157 			    sshdr.sense_key == UNIT_ATTENTION &&
2158 			    sshdr.asc == 0x29 && sshdr.ascq == 0x00)
2159 				/* Device reset might occur several times,
2160 				 * give it one more chance */
2161 				if (--reset_retries > 0)
2162 					continue;
2163 		}
2164 		retries--;
2165 
2166 	} while (the_result && retries);
2167 
2168 	if (the_result) {
2169 		sd_print_result(sdkp, "Read Capacity(10) failed", the_result);
2170 		read_capacity_error(sdkp, sdp, &sshdr, sense_valid, the_result);
2171 		return -EINVAL;
2172 	}
2173 
2174 	sector_size = get_unaligned_be32(&buffer[4]);
2175 	lba = get_unaligned_be32(&buffer[0]);
2176 
2177 	if (sdp->no_read_capacity_16 && (lba == 0xffffffff)) {
2178 		/* Some buggy (usb cardreader) devices return an lba of
2179 		   0xffffffff when the want to report a size of 0 (with
2180 		   which they really mean no media is present) */
2181 		sdkp->capacity = 0;
2182 		sdkp->physical_block_size = sector_size;
2183 		return sector_size;
2184 	}
2185 
2186 	if ((sizeof(sdkp->capacity) == 4) && (lba == 0xffffffff)) {
2187 		sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use a "
2188 			"kernel compiled with support for large block "
2189 			"devices.\n");
2190 		sdkp->capacity = 0;
2191 		return -EOVERFLOW;
2192 	}
2193 
2194 	sdkp->capacity = lba + 1;
2195 	sdkp->physical_block_size = sector_size;
2196 	return sector_size;
2197 }
2198 
2199 static int sd_try_rc16_first(struct scsi_device *sdp)
2200 {
2201 	if (sdp->host->max_cmd_len < 16)
2202 		return 0;
2203 	if (sdp->try_rc_10_first)
2204 		return 0;
2205 	if (sdp->scsi_level > SCSI_SPC_2)
2206 		return 1;
2207 	if (scsi_device_protection(sdp))
2208 		return 1;
2209 	return 0;
2210 }
2211 
2212 /*
2213  * read disk capacity
2214  */
2215 static void
2216 sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
2217 {
2218 	int sector_size;
2219 	struct scsi_device *sdp = sdkp->device;
2220 	sector_t old_capacity = sdkp->capacity;
2221 
2222 	if (sd_try_rc16_first(sdp)) {
2223 		sector_size = read_capacity_16(sdkp, sdp, buffer);
2224 		if (sector_size == -EOVERFLOW)
2225 			goto got_data;
2226 		if (sector_size == -ENODEV)
2227 			return;
2228 		if (sector_size < 0)
2229 			sector_size = read_capacity_10(sdkp, sdp, buffer);
2230 		if (sector_size < 0)
2231 			return;
2232 	} else {
2233 		sector_size = read_capacity_10(sdkp, sdp, buffer);
2234 		if (sector_size == -EOVERFLOW)
2235 			goto got_data;
2236 		if (sector_size < 0)
2237 			return;
2238 		if ((sizeof(sdkp->capacity) > 4) &&
2239 		    (sdkp->capacity > 0xffffffffULL)) {
2240 			int old_sector_size = sector_size;
2241 			sd_printk(KERN_NOTICE, sdkp, "Very big device. "
2242 					"Trying to use READ CAPACITY(16).\n");
2243 			sector_size = read_capacity_16(sdkp, sdp, buffer);
2244 			if (sector_size < 0) {
2245 				sd_printk(KERN_NOTICE, sdkp,
2246 					"Using 0xffffffff as device size\n");
2247 				sdkp->capacity = 1 + (sector_t) 0xffffffff;
2248 				sector_size = old_sector_size;
2249 				goto got_data;
2250 			}
2251 		}
2252 	}
2253 
2254 	/* Some devices are known to return the total number of blocks,
2255 	 * not the highest block number.  Some devices have versions
2256 	 * which do this and others which do not.  Some devices we might
2257 	 * suspect of doing this but we don't know for certain.
2258 	 *
2259 	 * If we know the reported capacity is wrong, decrement it.  If
2260 	 * we can only guess, then assume the number of blocks is even
2261 	 * (usually true but not always) and err on the side of lowering
2262 	 * the capacity.
2263 	 */
2264 	if (sdp->fix_capacity ||
2265 	    (sdp->guess_capacity && (sdkp->capacity & 0x01))) {
2266 		sd_printk(KERN_INFO, sdkp, "Adjusting the sector count "
2267 				"from its reported value: %llu\n",
2268 				(unsigned long long) sdkp->capacity);
2269 		--sdkp->capacity;
2270 	}
2271 
2272 got_data:
2273 	if (sector_size == 0) {
2274 		sector_size = 512;
2275 		sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
2276 			  "assuming 512.\n");
2277 	}
2278 
2279 	if (sector_size != 512 &&
2280 	    sector_size != 1024 &&
2281 	    sector_size != 2048 &&
2282 	    sector_size != 4096) {
2283 		sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
2284 			  sector_size);
2285 		/*
2286 		 * The user might want to re-format the drive with
2287 		 * a supported sectorsize.  Once this happens, it
2288 		 * would be relatively trivial to set the thing up.
2289 		 * For this reason, we leave the thing in the table.
2290 		 */
2291 		sdkp->capacity = 0;
2292 		/*
2293 		 * set a bogus sector size so the normal read/write
2294 		 * logic in the block layer will eventually refuse any
2295 		 * request on this device without tripping over power
2296 		 * of two sector size assumptions
2297 		 */
2298 		sector_size = 512;
2299 	}
2300 	blk_queue_logical_block_size(sdp->request_queue, sector_size);
2301 
2302 	{
2303 		char cap_str_2[10], cap_str_10[10];
2304 
2305 		string_get_size(sdkp->capacity, sector_size,
2306 				STRING_UNITS_2, cap_str_2, sizeof(cap_str_2));
2307 		string_get_size(sdkp->capacity, sector_size,
2308 				STRING_UNITS_10, cap_str_10,
2309 				sizeof(cap_str_10));
2310 
2311 		if (sdkp->first_scan || old_capacity != sdkp->capacity) {
2312 			sd_printk(KERN_NOTICE, sdkp,
2313 				  "%llu %d-byte logical blocks: (%s/%s)\n",
2314 				  (unsigned long long)sdkp->capacity,
2315 				  sector_size, cap_str_10, cap_str_2);
2316 
2317 			if (sdkp->physical_block_size != sector_size)
2318 				sd_printk(KERN_NOTICE, sdkp,
2319 					  "%u-byte physical blocks\n",
2320 					  sdkp->physical_block_size);
2321 		}
2322 	}
2323 
2324 	if (sdkp->capacity > 0xffffffff) {
2325 		sdp->use_16_for_rw = 1;
2326 		sdkp->max_xfer_blocks = SD_MAX_XFER_BLOCKS;
2327 	} else
2328 		sdkp->max_xfer_blocks = SD_DEF_XFER_BLOCKS;
2329 
2330 	/* Rescale capacity to 512-byte units */
2331 	if (sector_size == 4096)
2332 		sdkp->capacity <<= 3;
2333 	else if (sector_size == 2048)
2334 		sdkp->capacity <<= 2;
2335 	else if (sector_size == 1024)
2336 		sdkp->capacity <<= 1;
2337 
2338 	blk_queue_physical_block_size(sdp->request_queue,
2339 				      sdkp->physical_block_size);
2340 	sdkp->device->sector_size = sector_size;
2341 }
2342 
2343 /* called with buffer of length 512 */
2344 static inline int
2345 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
2346 		 unsigned char *buffer, int len, struct scsi_mode_data *data,
2347 		 struct scsi_sense_hdr *sshdr)
2348 {
2349 	return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
2350 			       SD_TIMEOUT, SD_MAX_RETRIES, data,
2351 			       sshdr);
2352 }
2353 
2354 /*
2355  * read write protect setting, if possible - called only in sd_revalidate_disk()
2356  * called with buffer of length SD_BUF_SIZE
2357  */
2358 static void
2359 sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
2360 {
2361 	int res;
2362 	struct scsi_device *sdp = sdkp->device;
2363 	struct scsi_mode_data data;
2364 	int old_wp = sdkp->write_prot;
2365 
2366 	set_disk_ro(sdkp->disk, 0);
2367 	if (sdp->skip_ms_page_3f) {
2368 		sd_first_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
2369 		return;
2370 	}
2371 
2372 	if (sdp->use_192_bytes_for_3f) {
2373 		res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
2374 	} else {
2375 		/*
2376 		 * First attempt: ask for all pages (0x3F), but only 4 bytes.
2377 		 * We have to start carefully: some devices hang if we ask
2378 		 * for more than is available.
2379 		 */
2380 		res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
2381 
2382 		/*
2383 		 * Second attempt: ask for page 0 When only page 0 is
2384 		 * implemented, a request for page 3F may return Sense Key
2385 		 * 5: Illegal Request, Sense Code 24: Invalid field in
2386 		 * CDB.
2387 		 */
2388 		if (!scsi_status_is_good(res))
2389 			res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
2390 
2391 		/*
2392 		 * Third attempt: ask 255 bytes, as we did earlier.
2393 		 */
2394 		if (!scsi_status_is_good(res))
2395 			res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
2396 					       &data, NULL);
2397 	}
2398 
2399 	if (!scsi_status_is_good(res)) {
2400 		sd_first_printk(KERN_WARNING, sdkp,
2401 			  "Test WP failed, assume Write Enabled\n");
2402 	} else {
2403 		sdkp->write_prot = ((data.device_specific & 0x80) != 0);
2404 		set_disk_ro(sdkp->disk, sdkp->write_prot);
2405 		if (sdkp->first_scan || old_wp != sdkp->write_prot) {
2406 			sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
2407 				  sdkp->write_prot ? "on" : "off");
2408 			sd_printk(KERN_DEBUG, sdkp,
2409 				  "Mode Sense: %02x %02x %02x %02x\n",
2410 				  buffer[0], buffer[1], buffer[2], buffer[3]);
2411 		}
2412 	}
2413 }
2414 
2415 /*
2416  * sd_read_cache_type - called only from sd_revalidate_disk()
2417  * called with buffer of length SD_BUF_SIZE
2418  */
2419 static void
2420 sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
2421 {
2422 	int len = 0, res;
2423 	struct scsi_device *sdp = sdkp->device;
2424 
2425 	int dbd;
2426 	int modepage;
2427 	int first_len;
2428 	struct scsi_mode_data data;
2429 	struct scsi_sense_hdr sshdr;
2430 	int old_wce = sdkp->WCE;
2431 	int old_rcd = sdkp->RCD;
2432 	int old_dpofua = sdkp->DPOFUA;
2433 
2434 
2435 	if (sdkp->cache_override)
2436 		return;
2437 
2438 	first_len = 4;
2439 	if (sdp->skip_ms_page_8) {
2440 		if (sdp->type == TYPE_RBC)
2441 			goto defaults;
2442 		else {
2443 			if (sdp->skip_ms_page_3f)
2444 				goto defaults;
2445 			modepage = 0x3F;
2446 			if (sdp->use_192_bytes_for_3f)
2447 				first_len = 192;
2448 			dbd = 0;
2449 		}
2450 	} else if (sdp->type == TYPE_RBC) {
2451 		modepage = 6;
2452 		dbd = 8;
2453 	} else {
2454 		modepage = 8;
2455 		dbd = 0;
2456 	}
2457 
2458 	/* cautiously ask */
2459 	res = sd_do_mode_sense(sdp, dbd, modepage, buffer, first_len,
2460 			&data, &sshdr);
2461 
2462 	if (!scsi_status_is_good(res))
2463 		goto bad_sense;
2464 
2465 	if (!data.header_length) {
2466 		modepage = 6;
2467 		first_len = 0;
2468 		sd_first_printk(KERN_ERR, sdkp,
2469 				"Missing header in MODE_SENSE response\n");
2470 	}
2471 
2472 	/* that went OK, now ask for the proper length */
2473 	len = data.length;
2474 
2475 	/*
2476 	 * We're only interested in the first three bytes, actually.
2477 	 * But the data cache page is defined for the first 20.
2478 	 */
2479 	if (len < 3)
2480 		goto bad_sense;
2481 	else if (len > SD_BUF_SIZE) {
2482 		sd_first_printk(KERN_NOTICE, sdkp, "Truncating mode parameter "
2483 			  "data from %d to %d bytes\n", len, SD_BUF_SIZE);
2484 		len = SD_BUF_SIZE;
2485 	}
2486 	if (modepage == 0x3F && sdp->use_192_bytes_for_3f)
2487 		len = 192;
2488 
2489 	/* Get the data */
2490 	if (len > first_len)
2491 		res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len,
2492 				&data, &sshdr);
2493 
2494 	if (scsi_status_is_good(res)) {
2495 		int offset = data.header_length + data.block_descriptor_length;
2496 
2497 		while (offset < len) {
2498 			u8 page_code = buffer[offset] & 0x3F;
2499 			u8 spf       = buffer[offset] & 0x40;
2500 
2501 			if (page_code == 8 || page_code == 6) {
2502 				/* We're interested only in the first 3 bytes.
2503 				 */
2504 				if (len - offset <= 2) {
2505 					sd_first_printk(KERN_ERR, sdkp,
2506 						"Incomplete mode parameter "
2507 							"data\n");
2508 					goto defaults;
2509 				} else {
2510 					modepage = page_code;
2511 					goto Page_found;
2512 				}
2513 			} else {
2514 				/* Go to the next page */
2515 				if (spf && len - offset > 3)
2516 					offset += 4 + (buffer[offset+2] << 8) +
2517 						buffer[offset+3];
2518 				else if (!spf && len - offset > 1)
2519 					offset += 2 + buffer[offset+1];
2520 				else {
2521 					sd_first_printk(KERN_ERR, sdkp,
2522 							"Incomplete mode "
2523 							"parameter data\n");
2524 					goto defaults;
2525 				}
2526 			}
2527 		}
2528 
2529 		sd_first_printk(KERN_ERR, sdkp, "No Caching mode page found\n");
2530 		goto defaults;
2531 
2532 	Page_found:
2533 		if (modepage == 8) {
2534 			sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
2535 			sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
2536 		} else {
2537 			sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
2538 			sdkp->RCD = 0;
2539 		}
2540 
2541 		sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
2542 		if (sdp->broken_fua) {
2543 			sd_first_printk(KERN_NOTICE, sdkp, "Disabling FUA\n");
2544 			sdkp->DPOFUA = 0;
2545 		} else if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
2546 			sd_first_printk(KERN_NOTICE, sdkp,
2547 				  "Uses READ/WRITE(6), disabling FUA\n");
2548 			sdkp->DPOFUA = 0;
2549 		}
2550 
2551 		/* No cache flush allowed for write protected devices */
2552 		if (sdkp->WCE && sdkp->write_prot)
2553 			sdkp->WCE = 0;
2554 
2555 		if (sdkp->first_scan || old_wce != sdkp->WCE ||
2556 		    old_rcd != sdkp->RCD || old_dpofua != sdkp->DPOFUA)
2557 			sd_printk(KERN_NOTICE, sdkp,
2558 				  "Write cache: %s, read cache: %s, %s\n",
2559 				  sdkp->WCE ? "enabled" : "disabled",
2560 				  sdkp->RCD ? "disabled" : "enabled",
2561 				  sdkp->DPOFUA ? "supports DPO and FUA"
2562 				  : "doesn't support DPO or FUA");
2563 
2564 		return;
2565 	}
2566 
2567 bad_sense:
2568 	if (scsi_sense_valid(&sshdr) &&
2569 	    sshdr.sense_key == ILLEGAL_REQUEST &&
2570 	    sshdr.asc == 0x24 && sshdr.ascq == 0x0)
2571 		/* Invalid field in CDB */
2572 		sd_first_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
2573 	else
2574 		sd_first_printk(KERN_ERR, sdkp,
2575 				"Asking for cache data failed\n");
2576 
2577 defaults:
2578 	if (sdp->wce_default_on) {
2579 		sd_first_printk(KERN_NOTICE, sdkp,
2580 				"Assuming drive cache: write back\n");
2581 		sdkp->WCE = 1;
2582 	} else {
2583 		sd_first_printk(KERN_ERR, sdkp,
2584 				"Assuming drive cache: write through\n");
2585 		sdkp->WCE = 0;
2586 	}
2587 	sdkp->RCD = 0;
2588 	sdkp->DPOFUA = 0;
2589 }
2590 
2591 /*
2592  * The ATO bit indicates whether the DIF application tag is available
2593  * for use by the operating system.
2594  */
2595 static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
2596 {
2597 	int res, offset;
2598 	struct scsi_device *sdp = sdkp->device;
2599 	struct scsi_mode_data data;
2600 	struct scsi_sense_hdr sshdr;
2601 
2602 	if (sdp->type != TYPE_DISK)
2603 		return;
2604 
2605 	if (sdkp->protection_type == 0)
2606 		return;
2607 
2608 	res = scsi_mode_sense(sdp, 1, 0x0a, buffer, 36, SD_TIMEOUT,
2609 			      SD_MAX_RETRIES, &data, &sshdr);
2610 
2611 	if (!scsi_status_is_good(res) || !data.header_length ||
2612 	    data.length < 6) {
2613 		sd_first_printk(KERN_WARNING, sdkp,
2614 			  "getting Control mode page failed, assume no ATO\n");
2615 
2616 		if (scsi_sense_valid(&sshdr))
2617 			sd_print_sense_hdr(sdkp, &sshdr);
2618 
2619 		return;
2620 	}
2621 
2622 	offset = data.header_length + data.block_descriptor_length;
2623 
2624 	if ((buffer[offset] & 0x3f) != 0x0a) {
2625 		sd_first_printk(KERN_ERR, sdkp, "ATO Got wrong page\n");
2626 		return;
2627 	}
2628 
2629 	if ((buffer[offset + 5] & 0x80) == 0)
2630 		return;
2631 
2632 	sdkp->ATO = 1;
2633 
2634 	return;
2635 }
2636 
2637 /**
2638  * sd_read_block_limits - Query disk device for preferred I/O sizes.
2639  * @disk: disk to query
2640  */
2641 static void sd_read_block_limits(struct scsi_disk *sdkp)
2642 {
2643 	unsigned int sector_sz = sdkp->device->sector_size;
2644 	const int vpd_len = 64;
2645 	u32 max_xfer_length;
2646 	unsigned char *buffer = kmalloc(vpd_len, GFP_KERNEL);
2647 
2648 	if (!buffer ||
2649 	    /* Block Limits VPD */
2650 	    scsi_get_vpd_page(sdkp->device, 0xb0, buffer, vpd_len))
2651 		goto out;
2652 
2653 	max_xfer_length = get_unaligned_be32(&buffer[8]);
2654 	if (max_xfer_length)
2655 		sdkp->max_xfer_blocks = max_xfer_length;
2656 
2657 	blk_queue_io_min(sdkp->disk->queue,
2658 			 get_unaligned_be16(&buffer[6]) * sector_sz);
2659 	blk_queue_io_opt(sdkp->disk->queue,
2660 			 get_unaligned_be32(&buffer[12]) * sector_sz);
2661 
2662 	if (buffer[3] == 0x3c) {
2663 		unsigned int lba_count, desc_count;
2664 
2665 		sdkp->max_ws_blocks = (u32)get_unaligned_be64(&buffer[36]);
2666 
2667 		if (!sdkp->lbpme)
2668 			goto out;
2669 
2670 		lba_count = get_unaligned_be32(&buffer[20]);
2671 		desc_count = get_unaligned_be32(&buffer[24]);
2672 
2673 		if (lba_count && desc_count)
2674 			sdkp->max_unmap_blocks = lba_count;
2675 
2676 		sdkp->unmap_granularity = get_unaligned_be32(&buffer[28]);
2677 
2678 		if (buffer[32] & 0x80)
2679 			sdkp->unmap_alignment =
2680 				get_unaligned_be32(&buffer[32]) & ~(1 << 31);
2681 
2682 		if (!sdkp->lbpvpd) { /* LBP VPD page not provided */
2683 
2684 			if (sdkp->max_unmap_blocks)
2685 				sd_config_discard(sdkp, SD_LBP_UNMAP);
2686 			else
2687 				sd_config_discard(sdkp, SD_LBP_WS16);
2688 
2689 		} else {	/* LBP VPD page tells us what to use */
2690 			if (sdkp->lbpu && sdkp->max_unmap_blocks && !sdkp->lbprz)
2691 				sd_config_discard(sdkp, SD_LBP_UNMAP);
2692 			else if (sdkp->lbpws)
2693 				sd_config_discard(sdkp, SD_LBP_WS16);
2694 			else if (sdkp->lbpws10)
2695 				sd_config_discard(sdkp, SD_LBP_WS10);
2696 			else if (sdkp->lbpu && sdkp->max_unmap_blocks)
2697 				sd_config_discard(sdkp, SD_LBP_UNMAP);
2698 			else
2699 				sd_config_discard(sdkp, SD_LBP_DISABLE);
2700 		}
2701 	}
2702 
2703  out:
2704 	kfree(buffer);
2705 }
2706 
2707 /**
2708  * sd_read_block_characteristics - Query block dev. characteristics
2709  * @disk: disk to query
2710  */
2711 static void sd_read_block_characteristics(struct scsi_disk *sdkp)
2712 {
2713 	unsigned char *buffer;
2714 	u16 rot;
2715 	const int vpd_len = 64;
2716 
2717 	buffer = kmalloc(vpd_len, GFP_KERNEL);
2718 
2719 	if (!buffer ||
2720 	    /* Block Device Characteristics VPD */
2721 	    scsi_get_vpd_page(sdkp->device, 0xb1, buffer, vpd_len))
2722 		goto out;
2723 
2724 	rot = get_unaligned_be16(&buffer[4]);
2725 
2726 	if (rot == 1) {
2727 		queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);
2728 		queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, sdkp->disk->queue);
2729 	}
2730 
2731  out:
2732 	kfree(buffer);
2733 }
2734 
2735 /**
2736  * sd_read_block_provisioning - Query provisioning VPD page
2737  * @disk: disk to query
2738  */
2739 static void sd_read_block_provisioning(struct scsi_disk *sdkp)
2740 {
2741 	unsigned char *buffer;
2742 	const int vpd_len = 8;
2743 
2744 	if (sdkp->lbpme == 0)
2745 		return;
2746 
2747 	buffer = kmalloc(vpd_len, GFP_KERNEL);
2748 
2749 	if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
2750 		goto out;
2751 
2752 	sdkp->lbpvpd	= 1;
2753 	sdkp->lbpu	= (buffer[5] >> 7) & 1;	/* UNMAP */
2754 	sdkp->lbpws	= (buffer[5] >> 6) & 1;	/* WRITE SAME(16) with UNMAP */
2755 	sdkp->lbpws10	= (buffer[5] >> 5) & 1;	/* WRITE SAME(10) with UNMAP */
2756 
2757  out:
2758 	kfree(buffer);
2759 }
2760 
2761 static void sd_read_write_same(struct scsi_disk *sdkp, unsigned char *buffer)
2762 {
2763 	struct scsi_device *sdev = sdkp->device;
2764 
2765 	if (sdev->host->no_write_same) {
2766 		sdev->no_write_same = 1;
2767 
2768 		return;
2769 	}
2770 
2771 	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, INQUIRY) < 0) {
2772 		/* too large values might cause issues with arcmsr */
2773 		int vpd_buf_len = 64;
2774 
2775 		sdev->no_report_opcodes = 1;
2776 
2777 		/* Disable WRITE SAME if REPORT SUPPORTED OPERATION
2778 		 * CODES is unsupported and the device has an ATA
2779 		 * Information VPD page (SAT).
2780 		 */
2781 		if (!scsi_get_vpd_page(sdev, 0x89, buffer, vpd_buf_len))
2782 			sdev->no_write_same = 1;
2783 	}
2784 
2785 	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME_16) == 1)
2786 		sdkp->ws16 = 1;
2787 
2788 	if (scsi_report_opcode(sdev, buffer, SD_BUF_SIZE, WRITE_SAME) == 1)
2789 		sdkp->ws10 = 1;
2790 }
2791 
2792 static int sd_try_extended_inquiry(struct scsi_device *sdp)
2793 {
2794 	/* Attempt VPD inquiry if the device blacklist explicitly calls
2795 	 * for it.
2796 	 */
2797 	if (sdp->try_vpd_pages)
2798 		return 1;
2799 	/*
2800 	 * Although VPD inquiries can go to SCSI-2 type devices,
2801 	 * some USB ones crash on receiving them, and the pages
2802 	 * we currently ask for are for SPC-3 and beyond
2803 	 */
2804 	if (sdp->scsi_level > SCSI_SPC_2 && !sdp->skip_vpd_pages)
2805 		return 1;
2806 	return 0;
2807 }
2808 
2809 /**
2810  *	sd_revalidate_disk - called the first time a new disk is seen,
2811  *	performs disk spin up, read_capacity, etc.
2812  *	@disk: struct gendisk we care about
2813  **/
2814 static int sd_revalidate_disk(struct gendisk *disk)
2815 {
2816 	struct scsi_disk *sdkp = scsi_disk(disk);
2817 	struct scsi_device *sdp = sdkp->device;
2818 	unsigned char *buffer;
2819 	unsigned int max_xfer;
2820 
2821 	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
2822 				      "sd_revalidate_disk\n"));
2823 
2824 	/*
2825 	 * If the device is offline, don't try and read capacity or any
2826 	 * of the other niceties.
2827 	 */
2828 	if (!scsi_device_online(sdp))
2829 		goto out;
2830 
2831 	buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
2832 	if (!buffer) {
2833 		sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
2834 			  "allocation failure.\n");
2835 		goto out;
2836 	}
2837 
2838 	sd_spinup_disk(sdkp);
2839 
2840 	/*
2841 	 * Without media there is no reason to ask; moreover, some devices
2842 	 * react badly if we do.
2843 	 */
2844 	if (sdkp->media_present) {
2845 		sd_read_capacity(sdkp, buffer);
2846 
2847 		if (sd_try_extended_inquiry(sdp)) {
2848 			sd_read_block_provisioning(sdkp);
2849 			sd_read_block_limits(sdkp);
2850 			sd_read_block_characteristics(sdkp);
2851 		}
2852 
2853 		sd_read_write_protect_flag(sdkp, buffer);
2854 		sd_read_cache_type(sdkp, buffer);
2855 		sd_read_app_tag_own(sdkp, buffer);
2856 		sd_read_write_same(sdkp, buffer);
2857 	}
2858 
2859 	sdkp->first_scan = 0;
2860 
2861 	/*
2862 	 * We now have all cache related info, determine how we deal
2863 	 * with flush requests.
2864 	 */
2865 	sd_set_flush_flag(sdkp);
2866 
2867 	max_xfer = sdkp->max_xfer_blocks;
2868 	max_xfer <<= ilog2(sdp->sector_size) - 9;
2869 
2870 	sdkp->disk->queue->limits.max_sectors =
2871 		min_not_zero(queue_max_hw_sectors(sdkp->disk->queue), max_xfer);
2872 
2873 	set_capacity(disk, sdkp->capacity);
2874 	sd_config_write_same(sdkp);
2875 	kfree(buffer);
2876 
2877  out:
2878 	return 0;
2879 }
2880 
2881 /**
2882  *	sd_unlock_native_capacity - unlock native capacity
2883  *	@disk: struct gendisk to set capacity for
2884  *
2885  *	Block layer calls this function if it detects that partitions
2886  *	on @disk reach beyond the end of the device.  If the SCSI host
2887  *	implements ->unlock_native_capacity() method, it's invoked to
2888  *	give it a chance to adjust the device capacity.
2889  *
2890  *	CONTEXT:
2891  *	Defined by block layer.  Might sleep.
2892  */
2893 static void sd_unlock_native_capacity(struct gendisk *disk)
2894 {
2895 	struct scsi_device *sdev = scsi_disk(disk)->device;
2896 
2897 	if (sdev->host->hostt->unlock_native_capacity)
2898 		sdev->host->hostt->unlock_native_capacity(sdev);
2899 }
2900 
2901 /**
2902  *	sd_format_disk_name - format disk name
2903  *	@prefix: name prefix - ie. "sd" for SCSI disks
2904  *	@index: index of the disk to format name for
2905  *	@buf: output buffer
2906  *	@buflen: length of the output buffer
2907  *
2908  *	SCSI disk names starts at sda.  The 26th device is sdz and the
2909  *	27th is sdaa.  The last one for two lettered suffix is sdzz
2910  *	which is followed by sdaaa.
2911  *
2912  *	This is basically 26 base counting with one extra 'nil' entry
2913  *	at the beginning from the second digit on and can be
2914  *	determined using similar method as 26 base conversion with the
2915  *	index shifted -1 after each digit is computed.
2916  *
2917  *	CONTEXT:
2918  *	Don't care.
2919  *
2920  *	RETURNS:
2921  *	0 on success, -errno on failure.
2922  */
2923 static int sd_format_disk_name(char *prefix, int index, char *buf, int buflen)
2924 {
2925 	const int base = 'z' - 'a' + 1;
2926 	char *begin = buf + strlen(prefix);
2927 	char *end = buf + buflen;
2928 	char *p;
2929 	int unit;
2930 
2931 	p = end - 1;
2932 	*p = '\0';
2933 	unit = base;
2934 	do {
2935 		if (p == begin)
2936 			return -EINVAL;
2937 		*--p = 'a' + (index % unit);
2938 		index = (index / unit) - 1;
2939 	} while (index >= 0);
2940 
2941 	memmove(begin, p, end - p);
2942 	memcpy(buf, prefix, strlen(prefix));
2943 
2944 	return 0;
2945 }
2946 
2947 /*
2948  * The asynchronous part of sd_probe
2949  */
2950 static void sd_probe_async(void *data, async_cookie_t cookie)
2951 {
2952 	struct scsi_disk *sdkp = data;
2953 	struct scsi_device *sdp;
2954 	struct gendisk *gd;
2955 	u32 index;
2956 	struct device *dev;
2957 
2958 	sdp = sdkp->device;
2959 	gd = sdkp->disk;
2960 	index = sdkp->index;
2961 	dev = &sdp->sdev_gendev;
2962 
2963 	gd->major = sd_major((index & 0xf0) >> 4);
2964 	gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
2965 	gd->minors = SD_MINORS;
2966 
2967 	gd->fops = &sd_fops;
2968 	gd->private_data = &sdkp->driver;
2969 	gd->queue = sdkp->device->request_queue;
2970 
2971 	/* defaults, until the device tells us otherwise */
2972 	sdp->sector_size = 512;
2973 	sdkp->capacity = 0;
2974 	sdkp->media_present = 1;
2975 	sdkp->write_prot = 0;
2976 	sdkp->cache_override = 0;
2977 	sdkp->WCE = 0;
2978 	sdkp->RCD = 0;
2979 	sdkp->ATO = 0;
2980 	sdkp->first_scan = 1;
2981 	sdkp->max_medium_access_timeouts = SD_MAX_MEDIUM_TIMEOUTS;
2982 
2983 	sd_revalidate_disk(gd);
2984 
2985 	gd->driverfs_dev = &sdp->sdev_gendev;
2986 	gd->flags = GENHD_FL_EXT_DEVT;
2987 	if (sdp->removable) {
2988 		gd->flags |= GENHD_FL_REMOVABLE;
2989 		gd->events |= DISK_EVENT_MEDIA_CHANGE;
2990 	}
2991 
2992 	blk_pm_runtime_init(sdp->request_queue, dev);
2993 	add_disk(gd);
2994 	if (sdkp->capacity)
2995 		sd_dif_config_host(sdkp);
2996 
2997 	sd_revalidate_disk(gd);
2998 
2999 	sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
3000 		  sdp->removable ? "removable " : "");
3001 	scsi_autopm_put_device(sdp);
3002 	put_device(&sdkp->dev);
3003 }
3004 
3005 /**
3006  *	sd_probe - called during driver initialization and whenever a
3007  *	new scsi device is attached to the system. It is called once
3008  *	for each scsi device (not just disks) present.
3009  *	@dev: pointer to device object
3010  *
3011  *	Returns 0 if successful (or not interested in this scsi device
3012  *	(e.g. scanner)); 1 when there is an error.
3013  *
3014  *	Note: this function is invoked from the scsi mid-level.
3015  *	This function sets up the mapping between a given
3016  *	<host,channel,id,lun> (found in sdp) and new device name
3017  *	(e.g. /dev/sda). More precisely it is the block device major
3018  *	and minor number that is chosen here.
3019  *
3020  *	Assume sd_probe is not re-entrant (for time being)
3021  *	Also think about sd_probe() and sd_remove() running coincidentally.
3022  **/
3023 static int sd_probe(struct device *dev)
3024 {
3025 	struct scsi_device *sdp = to_scsi_device(dev);
3026 	struct scsi_disk *sdkp;
3027 	struct gendisk *gd;
3028 	int index;
3029 	int error;
3030 
3031 	scsi_autopm_get_device(sdp);
3032 	error = -ENODEV;
3033 	if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
3034 		goto out;
3035 
3036 	SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
3037 					"sd_probe\n"));
3038 
3039 	error = -ENOMEM;
3040 	sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
3041 	if (!sdkp)
3042 		goto out;
3043 
3044 	gd = alloc_disk(SD_MINORS);
3045 	if (!gd)
3046 		goto out_free;
3047 
3048 	do {
3049 		if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
3050 			goto out_put;
3051 
3052 		spin_lock(&sd_index_lock);
3053 		error = ida_get_new(&sd_index_ida, &index);
3054 		spin_unlock(&sd_index_lock);
3055 	} while (error == -EAGAIN);
3056 
3057 	if (error) {
3058 		sdev_printk(KERN_WARNING, sdp, "sd_probe: memory exhausted.\n");
3059 		goto out_put;
3060 	}
3061 
3062 	error = sd_format_disk_name("sd", index, gd->disk_name, DISK_NAME_LEN);
3063 	if (error) {
3064 		sdev_printk(KERN_WARNING, sdp, "SCSI disk (sd) name length exceeded.\n");
3065 		goto out_free_index;
3066 	}
3067 
3068 	sdkp->device = sdp;
3069 	sdkp->driver = &sd_template;
3070 	sdkp->disk = gd;
3071 	sdkp->index = index;
3072 	atomic_set(&sdkp->openers, 0);
3073 	atomic_set(&sdkp->device->ioerr_cnt, 0);
3074 
3075 	if (!sdp->request_queue->rq_timeout) {
3076 		if (sdp->type != TYPE_MOD)
3077 			blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
3078 		else
3079 			blk_queue_rq_timeout(sdp->request_queue,
3080 					     SD_MOD_TIMEOUT);
3081 	}
3082 
3083 	device_initialize(&sdkp->dev);
3084 	sdkp->dev.parent = dev;
3085 	sdkp->dev.class = &sd_disk_class;
3086 	dev_set_name(&sdkp->dev, "%s", dev_name(dev));
3087 
3088 	error = device_add(&sdkp->dev);
3089 	if (error)
3090 		goto out_free_index;
3091 
3092 	get_device(dev);
3093 	dev_set_drvdata(dev, sdkp);
3094 
3095 	get_device(&sdkp->dev);	/* prevent release before async_schedule */
3096 	async_schedule_domain(sd_probe_async, sdkp, &scsi_sd_probe_domain);
3097 
3098 	return 0;
3099 
3100  out_free_index:
3101 	spin_lock(&sd_index_lock);
3102 	ida_remove(&sd_index_ida, index);
3103 	spin_unlock(&sd_index_lock);
3104  out_put:
3105 	put_disk(gd);
3106  out_free:
3107 	kfree(sdkp);
3108  out:
3109 	scsi_autopm_put_device(sdp);
3110 	return error;
3111 }
3112 
3113 /**
3114  *	sd_remove - called whenever a scsi disk (previously recognized by
3115  *	sd_probe) is detached from the system. It is called (potentially
3116  *	multiple times) during sd module unload.
3117  *	@sdp: pointer to mid level scsi device object
3118  *
3119  *	Note: this function is invoked from the scsi mid-level.
3120  *	This function potentially frees up a device name (e.g. /dev/sdc)
3121  *	that could be re-used by a subsequent sd_probe().
3122  *	This function is not called when the built-in sd driver is "exit-ed".
3123  **/
3124 static int sd_remove(struct device *dev)
3125 {
3126 	struct scsi_disk *sdkp;
3127 	dev_t devt;
3128 
3129 	sdkp = dev_get_drvdata(dev);
3130 	devt = disk_devt(sdkp->disk);
3131 	scsi_autopm_get_device(sdkp->device);
3132 
3133 	async_synchronize_full_domain(&scsi_sd_pm_domain);
3134 	async_synchronize_full_domain(&scsi_sd_probe_domain);
3135 	device_del(&sdkp->dev);
3136 	del_gendisk(sdkp->disk);
3137 	sd_shutdown(dev);
3138 
3139 	blk_register_region(devt, SD_MINORS, NULL,
3140 			    sd_default_probe, NULL, NULL);
3141 
3142 	mutex_lock(&sd_ref_mutex);
3143 	dev_set_drvdata(dev, NULL);
3144 	put_device(&sdkp->dev);
3145 	mutex_unlock(&sd_ref_mutex);
3146 
3147 	return 0;
3148 }
3149 
3150 /**
3151  *	scsi_disk_release - Called to free the scsi_disk structure
3152  *	@dev: pointer to embedded class device
3153  *
3154  *	sd_ref_mutex must be held entering this routine.  Because it is
3155  *	called on last put, you should always use the scsi_disk_get()
3156  *	scsi_disk_put() helpers which manipulate the semaphore directly
3157  *	and never do a direct put_device.
3158  **/
3159 static void scsi_disk_release(struct device *dev)
3160 {
3161 	struct scsi_disk *sdkp = to_scsi_disk(dev);
3162 	struct gendisk *disk = sdkp->disk;
3163 
3164 	spin_lock(&sd_index_lock);
3165 	ida_remove(&sd_index_ida, sdkp->index);
3166 	spin_unlock(&sd_index_lock);
3167 
3168 	disk->private_data = NULL;
3169 	put_disk(disk);
3170 	put_device(&sdkp->device->sdev_gendev);
3171 
3172 	kfree(sdkp);
3173 }
3174 
3175 static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
3176 {
3177 	unsigned char cmd[6] = { START_STOP };	/* START_VALID */
3178 	struct scsi_sense_hdr sshdr;
3179 	struct scsi_device *sdp = sdkp->device;
3180 	int res;
3181 
3182 	if (start)
3183 		cmd[4] |= 1;	/* START */
3184 
3185 	if (sdp->start_stop_pwr_cond)
3186 		cmd[4] |= start ? 1 << 4 : 3 << 4;	/* Active or Standby */
3187 
3188 	if (!scsi_device_online(sdp))
3189 		return -ENODEV;
3190 
3191 	res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
3192 			       SD_TIMEOUT, SD_MAX_RETRIES, NULL, REQ_PM);
3193 	if (res) {
3194 		sd_print_result(sdkp, "Start/Stop Unit failed", res);
3195 		if (driver_byte(res) & DRIVER_SENSE)
3196 			sd_print_sense_hdr(sdkp, &sshdr);
3197 		if (scsi_sense_valid(&sshdr) &&
3198 			/* 0x3a is medium not present */
3199 			sshdr.asc == 0x3a)
3200 			res = 0;
3201 	}
3202 
3203 	/* SCSI error codes must not go to the generic layer */
3204 	if (res)
3205 		return -EIO;
3206 
3207 	return 0;
3208 }
3209 
3210 /*
3211  * Send a SYNCHRONIZE CACHE instruction down to the device through
3212  * the normal SCSI command structure.  Wait for the command to
3213  * complete.
3214  */
3215 static void sd_shutdown(struct device *dev)
3216 {
3217 	struct scsi_disk *sdkp = dev_get_drvdata(dev);
3218 
3219 	if (!sdkp)
3220 		return;         /* this can happen */
3221 
3222 	if (pm_runtime_suspended(dev))
3223 		return;
3224 
3225 	if (sdkp->WCE && sdkp->media_present) {
3226 		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
3227 		sd_sync_cache(sdkp);
3228 	}
3229 
3230 	if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
3231 		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
3232 		sd_start_stop_device(sdkp, 0);
3233 	}
3234 }
3235 
3236 static int sd_suspend_common(struct device *dev, bool ignore_stop_errors)
3237 {
3238 	struct scsi_disk *sdkp = dev_get_drvdata(dev);
3239 	int ret = 0;
3240 
3241 	if (!sdkp)
3242 		return 0;	/* this can happen */
3243 
3244 	if (sdkp->WCE && sdkp->media_present) {
3245 		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
3246 		ret = sd_sync_cache(sdkp);
3247 		if (ret) {
3248 			/* ignore OFFLINE device */
3249 			if (ret == -ENODEV)
3250 				ret = 0;
3251 			goto done;
3252 		}
3253 	}
3254 
3255 	if (sdkp->device->manage_start_stop) {
3256 		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
3257 		/* an error is not worth aborting a system sleep */
3258 		ret = sd_start_stop_device(sdkp, 0);
3259 		if (ignore_stop_errors)
3260 			ret = 0;
3261 	}
3262 
3263 done:
3264 	return ret;
3265 }
3266 
3267 static int sd_suspend_system(struct device *dev)
3268 {
3269 	return sd_suspend_common(dev, true);
3270 }
3271 
3272 static int sd_suspend_runtime(struct device *dev)
3273 {
3274 	return sd_suspend_common(dev, false);
3275 }
3276 
3277 static int sd_resume(struct device *dev)
3278 {
3279 	struct scsi_disk *sdkp = dev_get_drvdata(dev);
3280 
3281 	if (!sdkp->device->manage_start_stop)
3282 		return 0;
3283 
3284 	sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
3285 	return sd_start_stop_device(sdkp, 1);
3286 }
3287 
3288 /**
3289  *	init_sd - entry point for this driver (both when built in or when
3290  *	a module).
3291  *
3292  *	Note: this function registers this driver with the scsi mid-level.
3293  **/
3294 static int __init init_sd(void)
3295 {
3296 	int majors = 0, i, err;
3297 
3298 	SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
3299 
3300 	for (i = 0; i < SD_MAJORS; i++) {
3301 		if (register_blkdev(sd_major(i), "sd") != 0)
3302 			continue;
3303 		majors++;
3304 		blk_register_region(sd_major(i), SD_MINORS, NULL,
3305 				    sd_default_probe, NULL, NULL);
3306 	}
3307 
3308 	if (!majors)
3309 		return -ENODEV;
3310 
3311 	err = class_register(&sd_disk_class);
3312 	if (err)
3313 		goto err_out;
3314 
3315 	sd_cdb_cache = kmem_cache_create("sd_ext_cdb", SD_EXT_CDB_SIZE,
3316 					 0, 0, NULL);
3317 	if (!sd_cdb_cache) {
3318 		printk(KERN_ERR "sd: can't init extended cdb cache\n");
3319 		err = -ENOMEM;
3320 		goto err_out_class;
3321 	}
3322 
3323 	sd_cdb_pool = mempool_create_slab_pool(SD_MEMPOOL_SIZE, sd_cdb_cache);
3324 	if (!sd_cdb_pool) {
3325 		printk(KERN_ERR "sd: can't init extended cdb pool\n");
3326 		err = -ENOMEM;
3327 		goto err_out_cache;
3328 	}
3329 
3330 	err = scsi_register_driver(&sd_template.gendrv);
3331 	if (err)
3332 		goto err_out_driver;
3333 
3334 	return 0;
3335 
3336 err_out_driver:
3337 	mempool_destroy(sd_cdb_pool);
3338 
3339 err_out_cache:
3340 	kmem_cache_destroy(sd_cdb_cache);
3341 
3342 err_out_class:
3343 	class_unregister(&sd_disk_class);
3344 err_out:
3345 	for (i = 0; i < SD_MAJORS; i++)
3346 		unregister_blkdev(sd_major(i), "sd");
3347 	return err;
3348 }
3349 
3350 /**
3351  *	exit_sd - exit point for this driver (when it is a module).
3352  *
3353  *	Note: this function unregisters this driver from the scsi mid-level.
3354  **/
3355 static void __exit exit_sd(void)
3356 {
3357 	int i;
3358 
3359 	SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));
3360 
3361 	scsi_unregister_driver(&sd_template.gendrv);
3362 	mempool_destroy(sd_cdb_pool);
3363 	kmem_cache_destroy(sd_cdb_cache);
3364 
3365 	class_unregister(&sd_disk_class);
3366 
3367 	for (i = 0; i < SD_MAJORS; i++) {
3368 		blk_unregister_region(sd_major(i), SD_MINORS);
3369 		unregister_blkdev(sd_major(i), "sd");
3370 	}
3371 }
3372 
3373 module_init(init_sd);
3374 module_exit(exit_sd);
3375 
3376 static void sd_print_sense_hdr(struct scsi_disk *sdkp,
3377 			       struct scsi_sense_hdr *sshdr)
3378 {
3379 	scsi_print_sense_hdr(sdkp->device,
3380 			     sdkp->disk ? sdkp->disk->disk_name : NULL, sshdr);
3381 }
3382 
3383 static void sd_print_result(const struct scsi_disk *sdkp, const char *msg,
3384 			    int result)
3385 {
3386 	const char *hb_string = scsi_hostbyte_string(result);
3387 	const char *db_string = scsi_driverbyte_string(result);
3388 
3389 	if (hb_string || db_string)
3390 		sd_printk(KERN_INFO, sdkp,
3391 			  "%s: Result: hostbyte=%s driverbyte=%s\n", msg,
3392 			  hb_string ? hb_string : "invalid",
3393 			  db_string ? db_string : "invalid");
3394 	else
3395 		sd_printk(KERN_INFO, sdkp,
3396 			  "%s: Result: hostbyte=0x%02x driverbyte=0x%02x\n",
3397 			  msg, host_byte(result), driver_byte(result));
3398 }
3399 
3400