sd.c 50.1 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
/*
 *      sd.c Copyright (C) 1992 Drew Eckhardt
 *           Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
 *
 *      Linux scsi disk driver
 *              Initial versions: Drew Eckhardt
 *              Subsequent revisions: Eric Youngdale
 *	Modification history:
 *       - Drew Eckhardt <drew@colorado.edu> original
 *       - Eric Youngdale <eric@andante.org> add scatter-gather, multiple 
 *         outstanding request, and other enhancements.
 *         Support loadable low-level scsi drivers.
 *       - Jirka Hanika <geo@ff.cuni.cz> support more scsi disks using 
 *         eight major numbers.
 *       - Richard Gooch <rgooch@atnf.csiro.au> support devfs.
 *	 - Torben Mathiasen <tmm@image.dk> Resource allocation fixes in 
 *	   sd_init and cleanups.
 *	 - Alex Davis <letmein@erols.com> Fix problem where partition info
 *	   not being read in sd_open. Fix problem where removable media 
 *	   could be ejected after sd_open.
 *	 - Douglas Gilbert <dgilbert@interlog.com> cleanup for lk 2.5.x
 *	 - Badari Pulavarty <pbadari@us.ibm.com>, Matthew Wilcox 
 *	   <willy@debian.org>, Kurt Garloff <garloff@suse.de>: 
 *	   Support 32k/1M disks.
 *
 *	Logging policy (needs CONFIG_SCSI_LOGGING defined):
 *	 - setting up transfer: SCSI_LOG_HLQUEUE levels 1 and 2
 *	 - end of transfer (bh + scsi_lib): SCSI_LOG_HLCOMPLETE level 1
 *	 - entering sd_ioctl: SCSI_LOG_IOCTL level 1
 *	 - entering other commands: SCSI_LOG_HLQUEUE level 3
 *	Note: when the logging level is set by the user, it must be greater
 *	than the level indicated above to trigger output.	
 */

#include <linux/module.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/bio.h>
#include <linux/genhd.h>
#include <linux/hdreg.h>
#include <linux/errno.h>
#include <linux/idr.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/blkpg.h>
#include <linux/delay.h>
49
#include <linux/mutex.h>
L
Linus Torvalds 已提交
50 51 52 53 54 55 56 57 58 59 60
#include <asm/uaccess.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsicam.h>
61
#include <scsi/sd.h>
L
Linus Torvalds 已提交
62 63 64

#include "scsi_logging.h"

65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84
MODULE_AUTHOR("Eric Youngdale");
MODULE_DESCRIPTION("SCSI disk (sd) driver");
MODULE_LICENSE("GPL");

MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK0_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK1_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK2_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK3_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK4_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK5_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK6_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK7_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK8_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK9_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK10_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK11_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK12_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK13_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK14_MAJOR);
MODULE_ALIAS_BLOCKDEV_MAJOR(SCSI_DISK15_MAJOR);
85 86 87
MODULE_ALIAS_SCSI_DEVICE(TYPE_DISK);
MODULE_ALIAS_SCSI_DEVICE(TYPE_MOD);
MODULE_ALIAS_SCSI_DEVICE(TYPE_RBC);
88

L
Linus Torvalds 已提交
89 90 91 92 93 94
static DEFINE_IDR(sd_index_idr);
static DEFINE_SPINLOCK(sd_index_lock);

/* This semaphore is used to mediate the 0->1 reference get in the
 * face of object destruction (i.e. we can't allow a get on an
 * object after last put) */
95
static DEFINE_MUTEX(sd_ref_mutex);
L
Linus Torvalds 已提交
96

97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119
static const char *sd_cache_types[] = {
	"write through", "none", "write back",
	"write back, no read (daft)"
};

static ssize_t sd_store_cache_type(struct class_device *cdev, const char *buf,
				   size_t count)
{
	int i, ct = -1, rcd, wce, sp;
	struct scsi_disk *sdkp = to_scsi_disk(cdev);
	struct scsi_device *sdp = sdkp->device;
	char buffer[64];
	char *buffer_data;
	struct scsi_mode_data data;
	struct scsi_sense_hdr sshdr;
	int len;

	if (sdp->type != TYPE_DISK)
		/* no cache control on RBC devices; theoretically they
		 * can do it, but there's probably so many exceptions
		 * it's not worth the risk */
		return -EINVAL;

120
	for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) {
121 122 123 124 125 126 127 128 129 130 131 132 133 134
		const int len = strlen(sd_cache_types[i]);
		if (strncmp(sd_cache_types[i], buf, len) == 0 &&
		    buf[len] == '\n') {
			ct = i;
			break;
		}
	}
	if (ct < 0)
		return -EINVAL;
	rcd = ct & 0x01 ? 1 : 0;
	wce = ct & 0x02 ? 1 : 0;
	if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT,
			    SD_MAX_RETRIES, &data, NULL))
		return -EINVAL;
135
	len = min_t(size_t, sizeof(buffer), data.length - data.header_length -
136 137 138 139 140 141 142 143 144 145
		  data.block_descriptor_length);
	buffer_data = buffer + data.header_length +
		data.block_descriptor_length;
	buffer_data[2] &= ~0x05;
	buffer_data[2] |= wce << 2 | rcd;
	sp = buffer_data[0] & 0x80 ? 1 : 0;

	if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT,
			     SD_MAX_RETRIES, &data, &sshdr)) {
		if (scsi_sense_valid(&sshdr))
146
			sd_print_sense_hdr(sdkp, &sshdr);
147 148 149 150 151 152
		return -EINVAL;
	}
	sd_revalidate_disk(sdkp->disk);
	return count;
}

153 154 155 156 157 158 159 160 161 162 163 164 165 166
static ssize_t sd_store_manage_start_stop(struct class_device *cdev,
					  const char *buf, size_t count)
{
	struct scsi_disk *sdkp = to_scsi_disk(cdev);
	struct scsi_device *sdp = sdkp->device;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	sdp->manage_start_stop = simple_strtoul(buf, NULL, 10);

	return count;
}

167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183
static ssize_t sd_store_allow_restart(struct class_device *cdev, const char *buf,
				      size_t count)
{
	struct scsi_disk *sdkp = to_scsi_disk(cdev);
	struct scsi_device *sdp = sdkp->device;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	if (sdp->type != TYPE_DISK)
		return -EINVAL;

	sdp->allow_restart = simple_strtoul(buf, NULL, 10);

	return count;
}

184 185 186 187 188 189 190 191 192 193 194 195 196 197 198
static ssize_t sd_show_cache_type(struct class_device *cdev, char *buf)
{
	struct scsi_disk *sdkp = to_scsi_disk(cdev);
	int ct = sdkp->RCD + 2*sdkp->WCE;

	return snprintf(buf, 40, "%s\n", sd_cache_types[ct]);
}

static ssize_t sd_show_fua(struct class_device *cdev, char *buf)
{
	struct scsi_disk *sdkp = to_scsi_disk(cdev);

	return snprintf(buf, 20, "%u\n", sdkp->DPOFUA);
}

199 200 201 202 203 204 205 206
static ssize_t sd_show_manage_start_stop(struct class_device *cdev, char *buf)
{
	struct scsi_disk *sdkp = to_scsi_disk(cdev);
	struct scsi_device *sdp = sdkp->device;

	return snprintf(buf, 20, "%u\n", sdp->manage_start_stop);
}

207 208 209 210 211 212 213
static ssize_t sd_show_allow_restart(struct class_device *cdev, char *buf)
{
	struct scsi_disk *sdkp = to_scsi_disk(cdev);

	return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart);
}

214 215 216 217
static struct class_device_attribute sd_disk_attrs[] = {
	__ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type,
	       sd_store_cache_type),
	__ATTR(FUA, S_IRUGO, sd_show_fua, NULL),
218 219
	__ATTR(allow_restart, S_IRUGO|S_IWUSR, sd_show_allow_restart,
	       sd_store_allow_restart),
220 221
	__ATTR(manage_start_stop, S_IRUGO|S_IWUSR, sd_show_manage_start_stop,
	       sd_store_manage_start_stop),
222 223 224 225 226 227 228 229 230
	__ATTR_NULL,
};

static struct class sd_disk_class = {
	.name		= "scsi_disk",
	.owner		= THIS_MODULE,
	.release	= scsi_disk_release,
	.class_dev_attrs = sd_disk_attrs,
};
L
Linus Torvalds 已提交
231 232 233 234 235 236 237

static struct scsi_driver sd_template = {
	.owner			= THIS_MODULE,
	.gendrv = {
		.name		= "sd",
		.probe		= sd_probe,
		.remove		= sd_remove,
238 239
		.suspend	= sd_suspend,
		.resume		= sd_resume,
L
Linus Torvalds 已提交
240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280
		.shutdown	= sd_shutdown,
	},
	.rescan			= sd_rescan,
	.init_command		= sd_init_command,
	.issue_flush		= sd_issue_flush,
};

/*
 * Device no to disk mapping:
 * 
 *       major         disc2     disc  p1
 *   |............|.............|....|....| <- dev_t
 *    31        20 19          8 7  4 3  0
 * 
 * Inside a major, we have 16k disks, however mapped non-
 * contiguously. The first 16 disks are for major0, the next
 * ones with major1, ... Disk 256 is for major0 again, disk 272 
 * for major1, ... 
 * As we stay compatible with our numbering scheme, we can reuse 
 * the well-know SCSI majors 8, 65--71, 136--143.
 */
static int sd_major(int major_idx)
{
	switch (major_idx) {
	case 0:
		return SCSI_DISK0_MAJOR;
	case 1 ... 7:
		return SCSI_DISK1_MAJOR + major_idx - 1;
	case 8 ... 15:
		return SCSI_DISK8_MAJOR + major_idx - 8;
	default:
		BUG();
		return 0;	/* shut up gcc */
	}
}

static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
{
	return container_of(disk->private_data, struct scsi_disk, driver);
}

A
Alan Stern 已提交
281
static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
L
Linus Torvalds 已提交
282 283 284
{
	struct scsi_disk *sdkp = NULL;

A
Alan Stern 已提交
285 286 287
	if (disk->private_data) {
		sdkp = scsi_disk(disk);
		if (scsi_device_get(sdkp->device) == 0)
288
			class_device_get(&sdkp->cdev);
A
Alan Stern 已提交
289 290 291 292 293 294 295 296 297 298
		else
			sdkp = NULL;
	}
	return sdkp;
}

static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
{
	struct scsi_disk *sdkp;

299
	mutex_lock(&sd_ref_mutex);
A
Alan Stern 已提交
300
	sdkp = __scsi_disk_get(disk);
301
	mutex_unlock(&sd_ref_mutex);
L
Linus Torvalds 已提交
302
	return sdkp;
A
Alan Stern 已提交
303
}
L
Linus Torvalds 已提交
304

A
Alan Stern 已提交
305 306 307 308
static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev)
{
	struct scsi_disk *sdkp;

309
	mutex_lock(&sd_ref_mutex);
A
Alan Stern 已提交
310 311 312
	sdkp = dev_get_drvdata(dev);
	if (sdkp)
		sdkp = __scsi_disk_get(sdkp->disk);
313
	mutex_unlock(&sd_ref_mutex);
L
Linus Torvalds 已提交
314 315 316 317 318 319 320
	return sdkp;
}

static void scsi_disk_put(struct scsi_disk *sdkp)
{
	struct scsi_device *sdev = sdkp->device;

321
	mutex_lock(&sd_ref_mutex);
322
	class_device_put(&sdkp->cdev);
L
Linus Torvalds 已提交
323
	scsi_device_put(sdev);
324
	mutex_unlock(&sd_ref_mutex);
L
Linus Torvalds 已提交
325 326 327 328 329 330 331 332 333 334 335 336 337 338
}

/**
 *	sd_init_command - build a scsi (read or write) command from
 *	information in the request structure.
 *	@SCpnt: pointer to mid-level's per scsi command structure that
 *	contains request and into which the scsi command is written
 *
 *	Returns 1 if successful and 0 if error (or cannot be done now).
 **/
static int sd_init_command(struct scsi_cmnd * SCpnt)
{
	struct scsi_device *sdp = SCpnt->device;
	struct request *rq = SCpnt->request;
339 340 341 342
	struct gendisk *disk = rq->rq_disk;
	sector_t block = rq->sector;
	unsigned int this_count = SCpnt->request_bufflen >> 9;
	unsigned int timeout = sdp->timeout;
L
Linus Torvalds 已提交
343

344 345 346 347 348
	SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
					"sd_init_command: block=%llu, "
					"count=%d\n",
					(unsigned long long)block,
					this_count));
L
Linus Torvalds 已提交
349 350 351

	if (!sdp || !scsi_device_online(sdp) ||
 	    block + rq->nr_sectors > get_capacity(disk)) {
352 353 354 355 356
		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
						"Finishing %ld sectors\n",
						rq->nr_sectors));
		SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
						"Retry with 0x%p\n", SCpnt));
L
Linus Torvalds 已提交
357 358 359 360 361 362 363 364 365 366 367
		return 0;
	}

	if (sdp->changed) {
		/*
		 * quietly refuse to do anything to a changed disc until 
		 * the changed bit has been reset
		 */
		/* printk("SCSI disk has been changed. Prohibiting further I/O.\n"); */
		return 0;
	}
368 369
	SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
					(unsigned long long)block));
L
Linus Torvalds 已提交
370 371 372 373 374 375 376 377 378 379 380 381 382 383

	/*
	 * If we have a 1K hardware sectorsize, prevent access to single
	 * 512 byte sectors.  In theory we could handle this - in fact
	 * the scsi cdrom driver must be able to handle this because
	 * we typically use 1K blocksizes, and cdroms typically have
	 * 2K hardware sectorsizes.  Of course, things are simpler
	 * with the cdrom, since it is read-only.  For performance
	 * reasons, the filesystems should be able to handle this
	 * and not force the scsi disk driver to use bounce buffers
	 * for this.
	 */
	if (sdp->sector_size == 1024) {
		if ((block & 1) || (rq->nr_sectors & 1)) {
384 385
			scmd_printk(KERN_ERR, SCpnt,
				    "Bad block number requested\n");
L
Linus Torvalds 已提交
386 387 388 389 390 391 392 393
			return 0;
		} else {
			block = block >> 1;
			this_count = this_count >> 1;
		}
	}
	if (sdp->sector_size == 2048) {
		if ((block & 3) || (rq->nr_sectors & 3)) {
394 395
			scmd_printk(KERN_ERR, SCpnt,
				    "Bad block number requested\n");
L
Linus Torvalds 已提交
396 397 398 399 400 401 402 403
			return 0;
		} else {
			block = block >> 2;
			this_count = this_count >> 2;
		}
	}
	if (sdp->sector_size == 4096) {
		if ((block & 7) || (rq->nr_sectors & 7)) {
404 405
			scmd_printk(KERN_ERR, SCpnt,
				    "Bad block number requested\n");
L
Linus Torvalds 已提交
406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421
			return 0;
		} else {
			block = block >> 3;
			this_count = this_count >> 3;
		}
	}
	if (rq_data_dir(rq) == WRITE) {
		if (!sdp->writeable) {
			return 0;
		}
		SCpnt->cmnd[0] = WRITE_6;
		SCpnt->sc_data_direction = DMA_TO_DEVICE;
	} else if (rq_data_dir(rq) == READ) {
		SCpnt->cmnd[0] = READ_6;
		SCpnt->sc_data_direction = DMA_FROM_DEVICE;
	} else {
422
		scmd_printk(KERN_ERR, SCpnt, "Unknown command %x\n", rq->cmd_flags);
L
Linus Torvalds 已提交
423 424 425
		return 0;
	}

426 427 428 429 430
	SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
					"%s %d/%ld 512 byte blocks.\n",
					(rq_data_dir(rq) == WRITE) ?
					"writing" : "reading", this_count,
					rq->nr_sectors));
L
Linus Torvalds 已提交
431 432 433 434 435

	SCpnt->cmnd[1] = 0;
	
	if (block > 0xffffffff) {
		SCpnt->cmnd[0] += READ_16 - READ_6;
T
Tejun Heo 已提交
436
		SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
L
Linus Torvalds 已提交
437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455
		SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
		SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
		SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
		SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0;
		SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff;
		SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff;
		SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff;
		SCpnt->cmnd[9] = (unsigned char) block & 0xff;
		SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff;
		SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff;
		SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff;
		SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
		SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
	} else if ((this_count > 0xff) || (block > 0x1fffff) ||
		   SCpnt->device->use_10_for_rw) {
		if (this_count > 0xffff)
			this_count = 0xffff;

		SCpnt->cmnd[0] += READ_10 - READ_6;
T
Tejun Heo 已提交
456
		SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
L
Linus Torvalds 已提交
457 458 459 460 461 462 463 464
		SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
		SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
		SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
		SCpnt->cmnd[5] = (unsigned char) block & 0xff;
		SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
		SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
		SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
	} else {
T
Tejun Heo 已提交
465 466 467 468 469 470 471
		if (unlikely(blk_fua_rq(rq))) {
			/*
			 * This happens only if this drive failed
			 * 10byte rw command with ILLEGAL_REQUEST
			 * during operation and thus turned off
			 * use_10_for_rw.
			 */
472 473
			scmd_printk(KERN_ERR, SCpnt,
				    "FUA write on READ/WRITE(6) drive\n");
T
Tejun Heo 已提交
474 475 476
			return 0;
		}

L
Linus Torvalds 已提交
477 478 479 480 481 482
		SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
		SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
		SCpnt->cmnd[3] = (unsigned char) block & 0xff;
		SCpnt->cmnd[4] = (unsigned char) this_count;
		SCpnt->cmnd[5] = 0;
	}
483
	SCpnt->request_bufflen = this_count * sdp->sector_size;
L
Linus Torvalds 已提交
484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531

	/*
	 * We shouldn't disconnect in the middle of a sector, so with a dumb
	 * host adapter, it's safe to assume that we can at least transfer
	 * this many bytes between each connect / disconnect.
	 */
	SCpnt->transfersize = sdp->sector_size;
	SCpnt->underflow = this_count << 9;
	SCpnt->allowed = SD_MAX_RETRIES;
	SCpnt->timeout_per_command = timeout;

	/*
	 * This is the completion routine we use.  This is matched in terms
	 * of capability to this function.
	 */
	SCpnt->done = sd_rw_intr;

	/*
	 * This indicates that the command is ready from our end to be
	 * queued.
	 */
	return 1;
}

/**
 *	sd_open - open a scsi disk device
 *	@inode: only i_rdev member may be used
 *	@filp: only f_mode and f_flags may be used
 *
 *	Returns 0 if successful. Returns a negated errno value in case 
 *	of error.
 *
 *	Note: This can be called from a user context (e.g. fsck(1) )
 *	or from within the kernel (e.g. as a result of a mount(1) ).
 *	In the latter case @inode and @filp carry an abridged amount
 *	of information as noted above.
 **/
static int sd_open(struct inode *inode, struct file *filp)
{
	struct gendisk *disk = inode->i_bdev->bd_disk;
	struct scsi_disk *sdkp;
	struct scsi_device *sdev;
	int retval;

	if (!(sdkp = scsi_disk_get(disk)))
		return -ENXIO;


532
	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
L
Linus Torvalds 已提交
533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601

	sdev = sdkp->device;

	/*
	 * If the device is in error recovery, wait until it is done.
	 * If the device is offline, then disallow any access to it.
	 */
	retval = -ENXIO;
	if (!scsi_block_when_processing_errors(sdev))
		goto error_out;

	if (sdev->removable || sdkp->write_prot)
		check_disk_change(inode->i_bdev);

	/*
	 * If the drive is empty, just let the open fail.
	 */
	retval = -ENOMEDIUM;
	if (sdev->removable && !sdkp->media_present &&
	    !(filp->f_flags & O_NDELAY))
		goto error_out;

	/*
	 * If the device has the write protect tab set, have the open fail
	 * if the user expects to be able to write to the thing.
	 */
	retval = -EROFS;
	if (sdkp->write_prot && (filp->f_mode & FMODE_WRITE))
		goto error_out;

	/*
	 * It is possible that the disk changing stuff resulted in
	 * the device being taken offline.  If this is the case,
	 * report this to the user, and don't pretend that the
	 * open actually succeeded.
	 */
	retval = -ENXIO;
	if (!scsi_device_online(sdev))
		goto error_out;

	if (!sdkp->openers++ && sdev->removable) {
		if (scsi_block_when_processing_errors(sdev))
			scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
	}

	return 0;

error_out:
	scsi_disk_put(sdkp);
	return retval;	
}

/**
 *	sd_release - invoked when the (last) close(2) is called on this
 *	scsi disk.
 *	@inode: only i_rdev member may be used
 *	@filp: only f_mode and f_flags may be used
 *
 *	Returns 0. 
 *
 *	Note: may block (uninterruptible) if error recovery is underway
 *	on this disk.
 **/
static int sd_release(struct inode *inode, struct file *filp)
{
	struct gendisk *disk = inode->i_bdev->bd_disk;
	struct scsi_disk *sdkp = scsi_disk(disk);
	struct scsi_device *sdev = sdkp->device;

602
	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
L
Linus Torvalds 已提交
603 604 605 606 607 608 609 610 611 612 613 614 615 616

	if (!--sdkp->openers && sdev->removable) {
		if (scsi_block_when_processing_errors(sdev))
			scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
	}

	/*
	 * XXX and what if there are packets in flight and this close()
	 * XXX is followed by a "rmmod sd_mod"?
	 */
	scsi_disk_put(sdkp);
	return 0;
}

617
static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
L
Linus Torvalds 已提交
618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634
{
	struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
	struct scsi_device *sdp = sdkp->device;
	struct Scsi_Host *host = sdp->host;
	int diskinfo[4];

	/* default to most commonly used values */
        diskinfo[0] = 0x40;	/* 1 << 6 */
       	diskinfo[1] = 0x20;	/* 1 << 5 */
       	diskinfo[2] = sdkp->capacity >> 11;
	
	/* override with calculated, extended default, or driver values */
	if (host->hostt->bios_param)
		host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo);
	else
		scsicam_bios_param(bdev, sdkp->capacity, diskinfo);

635 636 637
	geo->heads = diskinfo[0];
	geo->sectors = diskinfo[1];
	geo->cylinders = diskinfo[2];
L
Linus Torvalds 已提交
638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686
	return 0;
}

/**
 *	sd_ioctl - process an ioctl
 *	@inode: only i_rdev/i_bdev members may be used
 *	@filp: only f_mode and f_flags may be used
 *	@cmd: ioctl command number
 *	@arg: this is third argument given to ioctl(2) system call.
 *	Often contains a pointer.
 *
 *	Returns 0 if successful (some ioctls return postive numbers on
 *	success as well). Returns a negated errno value in case of error.
 *
 *	Note: most ioctls are forward onto the block subsystem or further
 *	down in the scsi subsytem.
 **/
static int sd_ioctl(struct inode * inode, struct file * filp, 
		    unsigned int cmd, unsigned long arg)
{
	struct block_device *bdev = inode->i_bdev;
	struct gendisk *disk = bdev->bd_disk;
	struct scsi_device *sdp = scsi_disk(disk)->device;
	void __user *p = (void __user *)arg;
	int error;
    
	SCSI_LOG_IOCTL(1, printk("sd_ioctl: disk=%s, cmd=0x%x\n",
						disk->disk_name, cmd));

	/*
	 * If we are in the middle of error recovery, don't let anyone
	 * else try and use this device.  Also, if error recovery fails, it
	 * may try and take the device offline, in which case all further
	 * access to the device is prohibited.
	 */
	error = scsi_nonblockable_ioctl(sdp, cmd, p, filp);
	if (!scsi_block_when_processing_errors(sdp) || !error)
		return error;

	/*
	 * Send SCSI addressing ioctls directly to mid level, send other
	 * ioctls to block level and then onto mid level if they can't be
	 * resolved.
	 */
	switch (cmd) {
		case SCSI_IOCTL_GET_IDLUN:
		case SCSI_IOCTL_GET_BUS_NUMBER:
			return scsi_ioctl(sdp, cmd, p);
		default:
687
			error = scsi_cmd_ioctl(filp, disk->queue, disk, cmd, p);
L
Linus Torvalds 已提交
688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714
			if (error != -ENOTTY)
				return error;
	}
	return scsi_ioctl(sdp, cmd, p);
}

static void set_media_not_present(struct scsi_disk *sdkp)
{
	sdkp->media_present = 0;
	sdkp->capacity = 0;
	sdkp->device->changed = 1;
}

/**
 *	sd_media_changed - check if our medium changed
 *	@disk: kernel device descriptor 
 *
 *	Returns 0 if not applicable or no change; 1 if change
 *
 *	Note: this function is invoked from the block subsystem.
 **/
static int sd_media_changed(struct gendisk *disk)
{
	struct scsi_disk *sdkp = scsi_disk(disk);
	struct scsi_device *sdp = sdkp->device;
	int retval;

715
	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_media_changed\n"));
L
Linus Torvalds 已提交
716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767

	if (!sdp->removable)
		return 0;

	/*
	 * If the device is offline, don't send any commands - just pretend as
	 * if the command failed.  If the device ever comes back online, we
	 * can deal with it then.  It is only because of unrecoverable errors
	 * that we would ever take a device offline in the first place.
	 */
	if (!scsi_device_online(sdp))
		goto not_present;

	/*
	 * Using TEST_UNIT_READY enables differentiation between drive with
	 * no cartridge loaded - NOT READY, drive with changed cartridge -
	 * UNIT ATTENTION, or with same cartridge - GOOD STATUS.
	 *
	 * Drives that auto spin down. eg iomega jaz 1G, will be started
	 * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever
	 * sd_revalidate() is called.
	 */
	retval = -ENODEV;
	if (scsi_block_when_processing_errors(sdp))
		retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES);

	/*
	 * Unable to test, unit probably not ready.   This usually
	 * means there is no disc in the drive.  Mark as changed,
	 * and we will figure it out later once the drive is
	 * available again.
	 */
	if (retval)
		 goto not_present;

	/*
	 * For removable scsi disk we have to recognise the presence
	 * of a disk in the drive. This is kept in the struct scsi_disk
	 * struct and tested at open !  Daniel Roche (dan@lectra.fr)
	 */
	sdkp->media_present = 1;

	retval = sdp->changed;
	sdp->changed = 0;

	return retval;

not_present:
	set_media_not_present(sdkp);
	return 1;
}

768
static int sd_sync_cache(struct scsi_disk *sdkp)
L
Linus Torvalds 已提交
769 770
{
	int retries, res;
771
	struct scsi_device *sdp = sdkp->device;
772
	struct scsi_sense_hdr sshdr;
L
Linus Torvalds 已提交
773 774 775 776 777 778 779 780 781 782 783 784 785

	if (!scsi_device_online(sdp))
		return -ENODEV;


	for (retries = 3; retries > 0; --retries) {
		unsigned char cmd[10] = { 0 };

		cmd[0] = SYNCHRONIZE_CACHE;
		/*
		 * Leave the rest of the command zero to indicate
		 * flush everything.
		 */
786 787 788
		res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
				       SD_TIMEOUT, SD_MAX_RETRIES);
		if (res == 0)
L
Linus Torvalds 已提交
789 790 791
			break;
	}

792 793 794 795
	if (res) {
		sd_print_result(sdkp, res);
		if (driver_byte(res) & DRIVER_SENSE)
			sd_print_sense_hdr(sdkp, &sshdr);
L
Linus Torvalds 已提交
796 797
	}

798 799 800
	if (res)
		return -EIO;
	return 0;
L
Linus Torvalds 已提交
801 802 803 804
}

static int sd_issue_flush(struct device *dev, sector_t *error_sector)
{
A
Alan Stern 已提交
805 806
	int ret = 0;
	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
L
Linus Torvalds 已提交
807 808 809 810

	if (!sdkp)
               return -ENODEV;

A
Alan Stern 已提交
811
	if (sdkp->WCE)
812
		ret = sd_sync_cache(sdkp);
A
Alan Stern 已提交
813 814
	scsi_disk_put(sdkp);
	return ret;
L
Linus Torvalds 已提交
815 816
}

817
static void sd_prepare_flush(struct request_queue *q, struct request *rq)
L
Linus Torvalds 已提交
818
{
J
James Bottomley 已提交
819
	memset(rq->cmd, 0, sizeof(rq->cmd));
820
	rq->cmd_type = REQ_TYPE_BLOCK_PC;
J
James Bottomley 已提交
821 822
	rq->timeout = SD_TIMEOUT;
	rq->cmd[0] = SYNCHRONIZE_CACHE;
823
	rq->cmd_len = 10;
L
Linus Torvalds 已提交
824 825 826 827
}

static void sd_rescan(struct device *dev)
{
A
Alan Stern 已提交
828 829 830 831 832 833
	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);

	if (sdkp) {
		sd_revalidate_disk(sdkp->disk);
		scsi_disk_put(sdkp);
	}
L
Linus Torvalds 已提交
834 835 836 837 838 839 840 841 842 843
}


#ifdef CONFIG_COMPAT
/* 
 * This gets directly called from VFS. When the ioctl 
 * is not recognized we go back to the other translation paths. 
 */
static long sd_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
J
Josef Sipek 已提交
844
	struct block_device *bdev = file->f_path.dentry->d_inode->i_bdev;
L
Linus Torvalds 已提交
845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876
	struct gendisk *disk = bdev->bd_disk;
	struct scsi_device *sdev = scsi_disk(disk)->device;

	/*
	 * If we are in the middle of error recovery, don't let anyone
	 * else try and use this device.  Also, if error recovery fails, it
	 * may try and take the device offline, in which case all further
	 * access to the device is prohibited.
	 */
	if (!scsi_block_when_processing_errors(sdev))
		return -ENODEV;
	       
	if (sdev->host->hostt->compat_ioctl) {
		int ret;

		ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);

		return ret;
	}

	/* 
	 * Let the static ioctl translation table take care of it.
	 */
	return -ENOIOCTLCMD; 
}
#endif

static struct block_device_operations sd_fops = {
	.owner			= THIS_MODULE,
	.open			= sd_open,
	.release		= sd_release,
	.ioctl			= sd_ioctl,
877
	.getgeo			= sd_getgeo,
L
Linus Torvalds 已提交
878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894
#ifdef CONFIG_COMPAT
	.compat_ioctl		= sd_compat_ioctl,
#endif
	.media_changed		= sd_media_changed,
	.revalidate_disk	= sd_revalidate_disk,
};

/**
 *	sd_rw_intr - bottom half handler: called when the lower level
 *	driver has completed (successfully or otherwise) a scsi command.
 *	@SCpnt: mid-level's per command structure.
 *
 *	Note: potentially run from within an ISR. Must not block.
 **/
static void sd_rw_intr(struct scsi_cmnd * SCpnt)
{
	int result = SCpnt->result;
895 896 897 898
 	unsigned int xfer_size = SCpnt->request_bufflen;
 	unsigned int good_bytes = result ? 0 : xfer_size;
 	u64 start_lba = SCpnt->request->sector;
 	u64 bad_lba;
L
Linus Torvalds 已提交
899 900 901 902 903 904 905 906 907 908 909
	struct scsi_sense_hdr sshdr;
	int sense_valid = 0;
	int sense_deferred = 0;
	int info_valid;

	if (result) {
		sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
		if (sense_valid)
			sense_deferred = scsi_sense_is_deferred(&sshdr);
	}
#ifdef CONFIG_SCSI_LOGGING
910
	SCSI_LOG_HLCOMPLETE(1, scsi_print_result(SCpnt));
L
Linus Torvalds 已提交
911
	if (sense_valid) {
912 913 914 915 916 917
		SCSI_LOG_HLCOMPLETE(1, scmd_printk(KERN_INFO, SCpnt,
						   "sd_rw_intr: sb[respc,sk,asc,"
						   "ascq]=%x,%x,%x,%x\n",
						   sshdr.response_code,
						   sshdr.sense_key, sshdr.asc,
						   sshdr.ascq));
L
Linus Torvalds 已提交
918 919
	}
#endif
920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938
	if (driver_byte(result) != DRIVER_SENSE &&
	    (!sense_valid || sense_deferred))
		goto out;

	switch (sshdr.sense_key) {
	case HARDWARE_ERROR:
	case MEDIUM_ERROR:
		if (!blk_fs_request(SCpnt->request))
			goto out;
		info_valid = scsi_get_sense_info_fld(SCpnt->sense_buffer,
						     SCSI_SENSE_BUFFERSIZE,
						     &bad_lba);
		if (!info_valid)
			goto out;
		if (xfer_size <= SCpnt->device->sector_size)
			goto out;
		switch (SCpnt->device->sector_size) {
		case 256:
			start_lba <<= 1;
L
Linus Torvalds 已提交
939
			break;
940
		case 512:
L
Linus Torvalds 已提交
941
			break;
942 943 944 945 946 947 948 949
		case 1024:
			start_lba >>= 1;
			break;
		case 2048:
			start_lba >>= 2;
			break;
		case 4096:
			start_lba >>= 3;
L
Linus Torvalds 已提交
950 951
			break;
		default:
952 953
			/* Print something here with limiting frequency. */
			goto out;
L
Linus Torvalds 已提交
954 955
			break;
		}
956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982
		/* This computation should always be done in terms of
		 * the resolution of the device's medium.
		 */
		good_bytes = (bad_lba - start_lba)*SCpnt->device->sector_size;
		break;
	case RECOVERED_ERROR:
	case NO_SENSE:
		/* Inform the user, but make sure that it's not treated
		 * as a hard error.
		 */
		scsi_print_sense("sd", SCpnt);
		SCpnt->result = 0;
		memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
		good_bytes = xfer_size;
		break;
	case ILLEGAL_REQUEST:
		if (SCpnt->device->use_10_for_rw &&
		    (SCpnt->cmnd[0] == READ_10 ||
		     SCpnt->cmnd[0] == WRITE_10))
			SCpnt->device->use_10_for_rw = 0;
		if (SCpnt->device->use_10_for_ms &&
		    (SCpnt->cmnd[0] == MODE_SENSE_10 ||
		     SCpnt->cmnd[0] == MODE_SELECT_10))
			SCpnt->device->use_10_for_ms = 0;
		break;
	default:
		break;
L
Linus Torvalds 已提交
983
	}
984 985
 out:
	scsi_io_completion(SCpnt, good_bytes);
L
Linus Torvalds 已提交
986 987
}

988 989
static int media_not_present(struct scsi_disk *sdkp,
			     struct scsi_sense_hdr *sshdr)
L
Linus Torvalds 已提交
990 991
{

992
	if (!scsi_sense_valid(sshdr))
L
Linus Torvalds 已提交
993 994
		return 0;
	/* not invoked for commands that could return deferred errors */
995 996 997 998 999 1000
	if (sshdr->sense_key != NOT_READY &&
	    sshdr->sense_key != UNIT_ATTENTION)
		return 0;
	if (sshdr->asc != 0x3A) /* medium not present */
		return 0;

L
Linus Torvalds 已提交
1001 1002 1003 1004 1005 1006 1007 1008
	set_media_not_present(sdkp);
	return 1;
}

/*
 * spinup disk - called only in sd_revalidate_disk()
 */
static void
1009
sd_spinup_disk(struct scsi_disk *sdkp)
1010
{
L
Linus Torvalds 已提交
1011
	unsigned char cmd[10];
1012
	unsigned long spintime_expire = 0;
L
Linus Torvalds 已提交
1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028
	int retries, spintime;
	unsigned int the_result;
	struct scsi_sense_hdr sshdr;
	int sense_valid = 0;

	spintime = 0;

	/* Spin up drives, as required.  Only do this at boot time */
	/* Spinup needs to be done for module loads too. */
	do {
		retries = 0;

		do {
			cmd[0] = TEST_UNIT_READY;
			memset((void *) &cmd[1], 0, 9);

1029 1030 1031 1032
			the_result = scsi_execute_req(sdkp->device, cmd,
						      DMA_NONE, NULL, 0,
						      &sshdr, SD_TIMEOUT,
						      SD_MAX_RETRIES);
L
Linus Torvalds 已提交
1033

A
Alan Stern 已提交
1034 1035 1036 1037 1038 1039 1040 1041
			/*
			 * If the drive has indicated to us that it
			 * doesn't have any media in it, don't bother
			 * with any more polling.
			 */
			if (media_not_present(sdkp, &sshdr))
				return;

L
Linus Torvalds 已提交
1042
			if (the_result)
1043
				sense_valid = scsi_sense_valid(&sshdr);
L
Linus Torvalds 已提交
1044 1045 1046 1047 1048 1049 1050 1051 1052
			retries++;
		} while (retries < 3 && 
			 (!scsi_status_is_good(the_result) ||
			  ((driver_byte(the_result) & DRIVER_SENSE) &&
			  sense_valid && sshdr.sense_key == UNIT_ATTENTION)));

		if ((driver_byte(the_result) & DRIVER_SENSE) == 0) {
			/* no sense, TUR either succeeded or failed
			 * with a status error */
1053 1054 1055 1056
			if(!spintime && !scsi_status_is_good(the_result)) {
				sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
				sd_print_result(sdkp, the_result);
			}
L
Linus Torvalds 已提交
1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080
			break;
		}
					
		/*
		 * The device does not want the automatic start to be issued.
		 */
		if (sdkp->device->no_start_on_add) {
			break;
		}

		/*
		 * If manual intervention is required, or this is an
		 * absent USB storage device, a spinup is meaningless.
		 */
		if (sense_valid &&
		    sshdr.sense_key == NOT_READY &&
		    sshdr.asc == 4 && sshdr.ascq == 3) {
			break;		/* manual intervention required */

		/*
		 * Issue command to spin up drive when not ready
		 */
		} else if (sense_valid && sshdr.sense_key == NOT_READY) {
			if (!spintime) {
1081
				sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
L
Linus Torvalds 已提交
1082 1083 1084 1085
				cmd[0] = START_STOP;
				cmd[1] = 1;	/* Return immediately */
				memset((void *) &cmd[2], 0, 8);
				cmd[4] = 1;	/* Start spin cycle */
1086 1087 1088
				scsi_execute_req(sdkp->device, cmd, DMA_NONE,
						 NULL, 0, &sshdr,
						 SD_TIMEOUT, SD_MAX_RETRIES);
1089 1090
				spintime_expire = jiffies + 100 * HZ;
				spintime = 1;
L
Linus Torvalds 已提交
1091 1092 1093 1094
			}
			/* Wait 1 second for next try */
			msleep(1000);
			printk(".");
1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109

		/*
		 * Wait for USB flash devices with slow firmware.
		 * Yes, this sense key/ASC combination shouldn't
		 * occur here.  It's characteristic of these devices.
		 */
		} else if (sense_valid &&
				sshdr.sense_key == UNIT_ATTENTION &&
				sshdr.asc == 0x28) {
			if (!spintime) {
				spintime_expire = jiffies + 5 * HZ;
				spintime = 1;
			}
			/* Wait 1 second for next try */
			msleep(1000);
L
Linus Torvalds 已提交
1110 1111 1112 1113
		} else {
			/* we don't understand the sense code, so it's
			 * probably pointless to loop */
			if(!spintime) {
1114 1115
				sd_printk(KERN_NOTICE, sdkp, "Unit Not Ready\n");
				sd_print_sense_hdr(sdkp, &sshdr);
L
Linus Torvalds 已提交
1116 1117 1118 1119
			}
			break;
		}
				
1120
	} while (spintime && time_before_eq(jiffies, spintime_expire));
L
Linus Torvalds 已提交
1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133

	if (spintime) {
		if (scsi_status_is_good(the_result))
			printk("ready\n");
		else
			printk("not responding...\n");
	}
}

/*
 * read disk capacity
 */
static void
1134
sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer)
1135
{
L
Linus Torvalds 已提交
1136 1137 1138 1139 1140 1141
	unsigned char cmd[16];
	int the_result, retries;
	int sector_size = 0;
	int longrc = 0;
	struct scsi_sense_hdr sshdr;
	int sense_valid = 0;
1142
	struct scsi_device *sdp = sdkp->device;
L
Linus Torvalds 已提交
1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158

repeat:
	retries = 3;
	do {
		if (longrc) {
			memset((void *) cmd, 0, 16);
			cmd[0] = SERVICE_ACTION_IN;
			cmd[1] = SAI_READ_CAPACITY_16;
			cmd[13] = 12;
			memset((void *) buffer, 0, 12);
		} else {
			cmd[0] = READ_CAPACITY;
			memset((void *) &cmd[1], 0, 9);
			memset((void *) buffer, 0, 8);
		}
		
1159 1160 1161
		the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE,
					      buffer, longrc ? 12 : 8, &sshdr,
					      SD_TIMEOUT, SD_MAX_RETRIES);
L
Linus Torvalds 已提交
1162

1163
		if (media_not_present(sdkp, &sshdr))
L
Linus Torvalds 已提交
1164 1165 1166
			return;

		if (the_result)
1167
			sense_valid = scsi_sense_valid(&sshdr);
L
Linus Torvalds 已提交
1168 1169 1170 1171 1172
		retries--;

	} while (the_result && retries);

	if (the_result && !longrc) {
1173 1174
		sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY failed\n");
		sd_print_result(sdkp, the_result);
L
Linus Torvalds 已提交
1175
		if (driver_byte(the_result) & DRIVER_SENSE)
1176
			sd_print_sense_hdr(sdkp, &sshdr);
L
Linus Torvalds 已提交
1177
		else
1178
			sd_printk(KERN_NOTICE, sdkp, "Sense not available.\n");
L
Linus Torvalds 已提交
1179 1180 1181 1182 1183 1184 1185 1186 1187 1188

		/* Set dirty bit for removable devices if not ready -
		 * sometimes drives will not report this properly. */
		if (sdp->removable &&
		    sense_valid && sshdr.sense_key == NOT_READY)
			sdp->changed = 1;

		/* Either no media are present but the drive didn't tell us,
		   or they are present but the read capacity command fails */
		/* sdkp->media_present = 0; -- not always correct */
1189
		sdkp->capacity = 0; /* unknown mapped to zero - as usual */
L
Linus Torvalds 已提交
1190 1191 1192 1193

		return;
	} else if (the_result && longrc) {
		/* READ CAPACITY(16) has been failed */
1194 1195 1196 1197
		sd_printk(KERN_NOTICE, sdkp, "READ CAPACITY(16) failed\n");
		sd_print_result(sdkp, the_result);
		sd_printk(KERN_NOTICE, sdkp, "Use 0xffffffff as device size\n");

L
Linus Torvalds 已提交
1198 1199 1200 1201 1202 1203 1204 1205 1206 1207
		sdkp->capacity = 1 + (sector_t) 0xffffffff;		
		goto got_data;
	}	
	
	if (!longrc) {
		sector_size = (buffer[4] << 24) |
			(buffer[5] << 16) | (buffer[6] << 8) | buffer[7];
		if (buffer[0] == 0xff && buffer[1] == 0xff &&
		    buffer[2] == 0xff && buffer[3] == 0xff) {
			if(sizeof(sdkp->capacity) > 4) {
1208 1209
				sd_printk(KERN_NOTICE, sdkp, "Very big device. "
					  "Trying to use READ CAPACITY(16).\n");
L
Linus Torvalds 已提交
1210 1211 1212
				longrc = 1;
				goto repeat;
			}
1213 1214 1215
			sd_printk(KERN_ERR, sdkp, "Too big for this kernel. Use "
				  "a kernel compiled with support for large "
				  "block devices.\n");
L
Linus Torvalds 已提交
1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238
			sdkp->capacity = 0;
			goto got_data;
		}
		sdkp->capacity = 1 + (((sector_t)buffer[0] << 24) |
			(buffer[1] << 16) |
			(buffer[2] << 8) |
			buffer[3]);			
	} else {
		sdkp->capacity = 1 + (((u64)buffer[0] << 56) |
			((u64)buffer[1] << 48) |
			((u64)buffer[2] << 40) |
			((u64)buffer[3] << 32) |
			((sector_t)buffer[4] << 24) |
			((sector_t)buffer[5] << 16) |
			((sector_t)buffer[6] << 8)  |
			(sector_t)buffer[7]);
			
		sector_size = (buffer[8] << 24) |
			(buffer[9] << 16) | (buffer[10] << 8) | buffer[11];
	}	

	/* Some devices return the total number of sectors, not the
	 * highest sector number.  Make the necessary adjustment. */
1239
	if (sdp->fix_capacity) {
L
Linus Torvalds 已提交
1240 1241
		--sdkp->capacity;

1242 1243 1244 1245 1246 1247 1248 1249 1250
	/* Some devices have version which report the correct sizes
	 * and others which do not. We guess size according to a heuristic
	 * and err on the side of lowering the capacity. */
	} else {
		if (sdp->guess_capacity)
			if (sdkp->capacity & 0x01) /* odd sizes are odd */
				--sdkp->capacity;
	}

L
Linus Torvalds 已提交
1251 1252 1253
got_data:
	if (sector_size == 0) {
		sector_size = 512;
1254 1255
		sd_printk(KERN_NOTICE, sdkp, "Sector size 0 reported, "
			  "assuming 512.\n");
L
Linus Torvalds 已提交
1256 1257 1258 1259 1260 1261 1262
	}

	if (sector_size != 512 &&
	    sector_size != 1024 &&
	    sector_size != 2048 &&
	    sector_size != 4096 &&
	    sector_size != 256) {
1263 1264
		sd_printk(KERN_NOTICE, sdkp, "Unsupported sector size %d.\n",
			  sector_size);
L
Linus Torvalds 已提交
1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286
		/*
		 * The user might want to re-format the drive with
		 * a supported sectorsize.  Once this happens, it
		 * would be relatively trivial to set the thing up.
		 * For this reason, we leave the thing in the table.
		 */
		sdkp->capacity = 0;
		/*
		 * set a bogus sector size so the normal read/write
		 * logic in the block layer will eventually refuse any
		 * request on this device without tripping over power
		 * of two sector size assumptions
		 */
		sector_size = 512;
	}
	{
		/*
		 * The msdos fs needs to know the hardware sector size
		 * So I have created this table. See ll_rw_blk.c
		 * Jacques Gelinas (Jacques@solucorp.qc.ca)
		 */
		int hard_sector = sector_size;
1287
		sector_t sz = (sdkp->capacity/2) * (hard_sector/256);
1288
		struct request_queue *queue = sdp->request_queue;
1289
		sector_t mb = sz;
L
Linus Torvalds 已提交
1290 1291 1292

		blk_queue_hardsect_size(queue, hard_sector);
		/* avoid 64-bit division on 32-bit platforms */
1293
		sector_div(sz, 625);
L
Linus Torvalds 已提交
1294 1295 1296
		mb -= sz - 974;
		sector_div(mb, 1950);

1297 1298 1299 1300
		sd_printk(KERN_NOTICE, sdkp,
			  "%llu %d-byte hardware sectors (%llu MB)\n",
			  (unsigned long long)sdkp->capacity,
			  hard_sector, (unsigned long long)mb);
L
Linus Torvalds 已提交
1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317
	}

	/* Rescale capacity to 512-byte units */
	if (sector_size == 4096)
		sdkp->capacity <<= 3;
	else if (sector_size == 2048)
		sdkp->capacity <<= 2;
	else if (sector_size == 1024)
		sdkp->capacity <<= 1;
	else if (sector_size == 256)
		sdkp->capacity >>= 1;

	sdkp->device->sector_size = sector_size;
}

/* called with buffer of length 512 */
static inline int
1318 1319 1320
sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage,
		 unsigned char *buffer, int len, struct scsi_mode_data *data,
		 struct scsi_sense_hdr *sshdr)
L
Linus Torvalds 已提交
1321
{
1322
	return scsi_mode_sense(sdp, dbd, modepage, buffer, len,
1323
			       SD_TIMEOUT, SD_MAX_RETRIES, data,
1324
			       sshdr);
L
Linus Torvalds 已提交
1325 1326 1327 1328
}

/*
 * read write protect setting, if possible - called only in sd_revalidate_disk()
1329
 * called with buffer of length SD_BUF_SIZE
L
Linus Torvalds 已提交
1330 1331
 */
static void
1332
sd_read_write_protect_flag(struct scsi_disk *sdkp, unsigned char *buffer)
1333
{
L
Linus Torvalds 已提交
1334
	int res;
1335
	struct scsi_device *sdp = sdkp->device;
L
Linus Torvalds 已提交
1336 1337 1338
	struct scsi_mode_data data;

	set_disk_ro(sdkp->disk, 0);
1339
	if (sdp->skip_ms_page_3f) {
1340
		sd_printk(KERN_NOTICE, sdkp, "Assuming Write Enabled\n");
L
Linus Torvalds 已提交
1341 1342 1343
		return;
	}

1344 1345
	if (sdp->use_192_bytes_for_3f) {
		res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL);
L
Linus Torvalds 已提交
1346 1347 1348 1349 1350 1351
	} else {
		/*
		 * First attempt: ask for all pages (0x3F), but only 4 bytes.
		 * We have to start carefully: some devices hang if we ask
		 * for more than is available.
		 */
1352
		res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL);
L
Linus Torvalds 已提交
1353 1354 1355 1356 1357 1358 1359 1360

		/*
		 * Second attempt: ask for page 0 When only page 0 is
		 * implemented, a request for page 3F may return Sense Key
		 * 5: Illegal Request, Sense Code 24: Invalid field in
		 * CDB.
		 */
		if (!scsi_status_is_good(res))
1361
			res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL);
L
Linus Torvalds 已提交
1362 1363 1364 1365 1366

		/*
		 * Third attempt: ask 255 bytes, as we did earlier.
		 */
		if (!scsi_status_is_good(res))
1367 1368
			res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255,
					       &data, NULL);
L
Linus Torvalds 已提交
1369 1370 1371
	}

	if (!scsi_status_is_good(res)) {
1372 1373
		sd_printk(KERN_WARNING, sdkp,
			  "Test WP failed, assume Write Enabled\n");
L
Linus Torvalds 已提交
1374 1375 1376
	} else {
		sdkp->write_prot = ((data.device_specific & 0x80) != 0);
		set_disk_ro(sdkp->disk, sdkp->write_prot);
1377 1378 1379 1380 1381
		sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n",
			  sdkp->write_prot ? "on" : "off");
		sd_printk(KERN_DEBUG, sdkp,
			  "Mode Sense: %02x %02x %02x %02x\n",
			  buffer[0], buffer[1], buffer[2], buffer[3]);
L
Linus Torvalds 已提交
1382 1383 1384 1385 1386
	}
}

/*
 * sd_read_cache_type - called only from sd_revalidate_disk()
1387
 * called with buffer of length SD_BUF_SIZE
L
Linus Torvalds 已提交
1388 1389
 */
static void
1390
sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
1391
{
L
Linus Torvalds 已提交
1392
	int len = 0, res;
1393
	struct scsi_device *sdp = sdkp->device;
L
Linus Torvalds 已提交
1394

1395 1396
	int dbd;
	int modepage;
L
Linus Torvalds 已提交
1397 1398 1399
	struct scsi_mode_data data;
	struct scsi_sense_hdr sshdr;

1400
	if (sdp->skip_ms_page_8)
L
Linus Torvalds 已提交
1401 1402
		goto defaults;

1403
	if (sdp->type == TYPE_RBC) {
1404 1405 1406 1407 1408 1409 1410
		modepage = 6;
		dbd = 8;
	} else {
		modepage = 8;
		dbd = 0;
	}

L
Linus Torvalds 已提交
1411
	/* cautiously ask */
1412
	res = sd_do_mode_sense(sdp, dbd, modepage, buffer, 4, &data, &sshdr);
L
Linus Torvalds 已提交
1413 1414 1415 1416

	if (!scsi_status_is_good(res))
		goto bad_sense;

1417 1418
	if (!data.header_length) {
		modepage = 6;
1419
		sd_printk(KERN_ERR, sdkp, "Missing header in MODE_SENSE response\n");
1420 1421
	}

L
Linus Torvalds 已提交
1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435
	/* that went OK, now ask for the proper length */
	len = data.length;

	/*
	 * We're only interested in the first three bytes, actually.
	 * But the data cache page is defined for the first 20.
	 */
	if (len < 3)
		goto bad_sense;
	if (len > 20)
		len = 20;

	/* Take headers and block descriptors into account */
	len += data.header_length + data.block_descriptor_length;
1436 1437
	if (len > SD_BUF_SIZE)
		goto bad_sense;
L
Linus Torvalds 已提交
1438 1439

	/* Get the data */
1440
	res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len, &data, &sshdr);
L
Linus Torvalds 已提交
1441 1442

	if (scsi_status_is_good(res)) {
1443
		int offset = data.header_length + data.block_descriptor_length;
L
Linus Torvalds 已提交
1444

1445
		if (offset >= SD_BUF_SIZE - 2) {
1446
			sd_printk(KERN_ERR, sdkp, "Malformed MODE SENSE response\n");
1447 1448 1449
			goto defaults;
		}

1450
		if ((buffer[offset] & 0x3f) != modepage) {
1451
			sd_printk(KERN_ERR, sdkp, "Got wrong page\n");
1452 1453 1454 1455 1456 1457 1458 1459 1460 1461
			goto defaults;
		}

		if (modepage == 8) {
			sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0);
			sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0);
		} else {
			sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0);
			sdkp->RCD = 0;
		}
L
Linus Torvalds 已提交
1462

T
Tejun Heo 已提交
1463 1464
		sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
		if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
1465 1466
			sd_printk(KERN_NOTICE, sdkp,
				  "Uses READ/WRITE(6), disabling FUA\n");
T
Tejun Heo 已提交
1467 1468 1469
			sdkp->DPOFUA = 0;
		}

1470 1471
		sd_printk(KERN_NOTICE, sdkp,
		       "Write cache: %s, read cache: %s, %s\n",
1472 1473 1474 1475
		       sdkp->WCE ? "enabled" : "disabled",
		       sdkp->RCD ? "disabled" : "enabled",
		       sdkp->DPOFUA ? "supports DPO and FUA"
		       : "doesn't support DPO or FUA");
L
Linus Torvalds 已提交
1476 1477 1478 1479 1480

		return;
	}

bad_sense:
1481
	if (scsi_sense_valid(&sshdr) &&
L
Linus Torvalds 已提交
1482 1483
	    sshdr.sense_key == ILLEGAL_REQUEST &&
	    sshdr.asc == 0x24 && sshdr.ascq == 0x0)
1484 1485
		/* Invalid field in CDB */
		sd_printk(KERN_NOTICE, sdkp, "Cache data unavailable\n");
L
Linus Torvalds 已提交
1486
	else
1487
		sd_printk(KERN_ERR, sdkp, "Asking for cache data failed\n");
L
Linus Torvalds 已提交
1488 1489

defaults:
1490
	sd_printk(KERN_ERR, sdkp, "Assuming drive cache: write through\n");
L
Linus Torvalds 已提交
1491 1492
	sdkp->WCE = 0;
	sdkp->RCD = 0;
1493
	sdkp->DPOFUA = 0;
L
Linus Torvalds 已提交
1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505
}

/**
 *	sd_revalidate_disk - called the first time a new disk is seen,
 *	performs disk spin up, read_capacity, etc.
 *	@disk: struct gendisk we care about
 **/
static int sd_revalidate_disk(struct gendisk *disk)
{
	struct scsi_disk *sdkp = scsi_disk(disk);
	struct scsi_device *sdp = sdkp->device;
	unsigned char *buffer;
1506
	unsigned ordered;
L
Linus Torvalds 已提交
1507

1508 1509
	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp,
				      "sd_revalidate_disk\n"));
L
Linus Torvalds 已提交
1510 1511 1512 1513 1514 1515 1516 1517

	/*
	 * If the device is offline, don't try and read capacity or any
	 * of the other niceties.
	 */
	if (!scsi_device_online(sdp))
		goto out;

B
Bernhard Walle 已提交
1518
	buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL);
L
Linus Torvalds 已提交
1519
	if (!buffer) {
1520 1521
		sd_printk(KERN_WARNING, sdkp, "sd_revalidate_disk: Memory "
			  "allocation failure.\n");
1522
		goto out;
L
Linus Torvalds 已提交
1523 1524 1525 1526 1527 1528 1529 1530 1531 1532
	}

	/* defaults, until the device tells us otherwise */
	sdp->sector_size = 512;
	sdkp->capacity = 0;
	sdkp->media_present = 1;
	sdkp->write_prot = 0;
	sdkp->WCE = 0;
	sdkp->RCD = 0;

1533
	sd_spinup_disk(sdkp);
L
Linus Torvalds 已提交
1534 1535 1536 1537 1538 1539

	/*
	 * Without media there is no reason to ask; moreover, some devices
	 * react badly if we do.
	 */
	if (sdkp->media_present) {
1540 1541 1542
		sd_read_capacity(sdkp, buffer);
		sd_read_write_protect_flag(sdkp, buffer);
		sd_read_cache_type(sdkp, buffer);
L
Linus Torvalds 已提交
1543
	}
1544 1545 1546 1547 1548 1549 1550 1551

	/*
	 * We now have all cache related info, determine how we deal
	 * with ordered requests.  Note that as the current SCSI
	 * dispatch function can alter request order, we cannot use
	 * QUEUE_ORDERED_TAG_* even when ordered tag is supported.
	 */
	if (sdkp->WCE)
T
Tejun Heo 已提交
1552 1553
		ordered = sdkp->DPOFUA
			? QUEUE_ORDERED_DRAIN_FUA : QUEUE_ORDERED_DRAIN_FLUSH;
1554 1555 1556 1557 1558
	else
		ordered = QUEUE_ORDERED_DRAIN;

	blk_queue_ordered(sdkp->disk->queue, ordered, sd_prepare_flush);

L
Linus Torvalds 已提交
1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592
	set_capacity(disk, sdkp->capacity);
	kfree(buffer);

 out:
	return 0;
}

/**
 *	sd_probe - called during driver initialization and whenever a
 *	new scsi device is attached to the system. It is called once
 *	for each scsi device (not just disks) present.
 *	@dev: pointer to device object
 *
 *	Returns 0 if successful (or not interested in this scsi device 
 *	(e.g. scanner)); 1 when there is an error.
 *
 *	Note: this function is invoked from the scsi mid-level.
 *	This function sets up the mapping between a given 
 *	<host,channel,id,lun> (found in sdp) and new device name 
 *	(e.g. /dev/sda). More precisely it is the block device major 
 *	and minor number that is chosen here.
 *
 *	Assume sd_attach is not re-entrant (for time being)
 *	Also think about sd_attach() and sd_remove() running coincidentally.
 **/
static int sd_probe(struct device *dev)
{
	struct scsi_device *sdp = to_scsi_device(dev);
	struct scsi_disk *sdkp;
	struct gendisk *gd;
	u32 index;
	int error;

	error = -ENODEV;
1593
	if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
L
Linus Torvalds 已提交
1594 1595
		goto out;

1596 1597
	SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
					"sd_attach\n"));
L
Linus Torvalds 已提交
1598 1599

	error = -ENOMEM;
J
Jes Sorensen 已提交
1600
	sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL);
L
Linus Torvalds 已提交
1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626
	if (!sdkp)
		goto out;

	gd = alloc_disk(16);
	if (!gd)
		goto out_free;

	if (!idr_pre_get(&sd_index_idr, GFP_KERNEL))
		goto out_put;

	spin_lock(&sd_index_lock);
	error = idr_get_new(&sd_index_idr, NULL, &index);
	spin_unlock(&sd_index_lock);

	if (index >= SD_MAX_DISKS)
		error = -EBUSY;
	if (error)
		goto out_put;

	sdkp->device = sdp;
	sdkp->driver = &sd_template;
	sdkp->disk = gd;
	sdkp->index = index;
	sdkp->openers = 0;

	if (!sdp->timeout) {
1627
		if (sdp->type != TYPE_MOD)
L
Linus Torvalds 已提交
1628 1629 1630 1631 1632
			sdp->timeout = SD_TIMEOUT;
		else
			sdp->timeout = SD_MOD_TIMEOUT;
	}

1633 1634 1635 1636 1637 1638 1639 1640 1641 1642
	class_device_initialize(&sdkp->cdev);
	sdkp->cdev.dev = &sdp->sdev_gendev;
	sdkp->cdev.class = &sd_disk_class;
	strncpy(sdkp->cdev.class_id, sdp->sdev_gendev.bus_id, BUS_ID_SIZE);

	if (class_device_add(&sdkp->cdev))
		goto out_put;

	get_device(&sdp->sdev_gendev);

L
Linus Torvalds 已提交
1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661
	gd->major = sd_major((index & 0xf0) >> 4);
	gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00);
	gd->minors = 16;
	gd->fops = &sd_fops;

	if (index < 26) {
		sprintf(gd->disk_name, "sd%c", 'a' + index % 26);
	} else if (index < (26 + 1) * 26) {
		sprintf(gd->disk_name, "sd%c%c",
			'a' + index / 26 - 1,'a' + index % 26);
	} else {
		const unsigned int m1 = (index / 26 - 1) / 26 - 1;
		const unsigned int m2 = (index / 26 - 1) % 26;
		const unsigned int m3 =  index % 26;
		sprintf(gd->disk_name, "sd%c%c%c",
			'a' + m1, 'a' + m2, 'a' + m3);
	}

	gd->private_data = &sdkp->driver;
1662
	gd->queue = sdkp->device->request_queue;
L
Linus Torvalds 已提交
1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673

	sd_revalidate_disk(gd);

	gd->driverfs_dev = &sdp->sdev_gendev;
	gd->flags = GENHD_FL_DRIVERFS;
	if (sdp->removable)
		gd->flags |= GENHD_FL_REMOVABLE;

	dev_set_drvdata(dev, sdkp);
	add_disk(gd);

1674 1675
	sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
		  sdp->removable ? "removable " : "");
L
Linus Torvalds 已提交
1676 1677 1678

	return 0;

1679
 out_put:
L
Linus Torvalds 已提交
1680
	put_disk(gd);
1681
 out_free:
L
Linus Torvalds 已提交
1682
	kfree(sdkp);
1683
 out:
L
Linus Torvalds 已提交
1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701
	return error;
}

/**
 *	sd_remove - called whenever a scsi disk (previously recognized by
 *	sd_probe) is detached from the system. It is called (potentially
 *	multiple times) during sd module unload.
 *	@sdp: pointer to mid level scsi device object
 *
 *	Note: this function is invoked from the scsi mid-level.
 *	This function potentially frees up a device name (e.g. /dev/sdc)
 *	that could be re-used by a subsequent sd_probe().
 *	This function is not called when the built-in sd driver is "exit-ed".
 **/
static int sd_remove(struct device *dev)
{
	struct scsi_disk *sdkp = dev_get_drvdata(dev);

1702
	class_device_del(&sdkp->cdev);
L
Linus Torvalds 已提交
1703 1704
	del_gendisk(sdkp->disk);
	sd_shutdown(dev);
A
Alan Stern 已提交
1705

1706
	mutex_lock(&sd_ref_mutex);
A
Alan Stern 已提交
1707
	dev_set_drvdata(dev, NULL);
1708
	class_device_put(&sdkp->cdev);
1709
	mutex_unlock(&sd_ref_mutex);
L
Linus Torvalds 已提交
1710 1711 1712 1713 1714 1715

	return 0;
}

/**
 *	scsi_disk_release - Called to free the scsi_disk structure
1716
 *	@cdev: pointer to embedded class device
L
Linus Torvalds 已提交
1717
 *
1718
 *	sd_ref_mutex must be held entering this routine.  Because it is
L
Linus Torvalds 已提交
1719 1720
 *	called on last put, you should always use the scsi_disk_get()
 *	scsi_disk_put() helpers which manipulate the semaphore directly
1721
 *	and never do a direct class_device_put().
L
Linus Torvalds 已提交
1722
 **/
1723
static void scsi_disk_release(struct class_device *cdev)
L
Linus Torvalds 已提交
1724
{
1725
	struct scsi_disk *sdkp = to_scsi_disk(cdev);
L
Linus Torvalds 已提交
1726 1727 1728 1729 1730 1731 1732 1733
	struct gendisk *disk = sdkp->disk;
	
	spin_lock(&sd_index_lock);
	idr_remove(&sd_index_idr, sdkp->index);
	spin_unlock(&sd_index_lock);

	disk->private_data = NULL;
	put_disk(disk);
A
Alan Stern 已提交
1734
	put_device(&sdkp->device->sdev_gendev);
L
Linus Torvalds 已提交
1735 1736 1737 1738

	kfree(sdkp);
}

1739
static int sd_start_stop_device(struct scsi_disk *sdkp, int start)
1740 1741 1742
{
	unsigned char cmd[6] = { START_STOP };	/* START_VALID */
	struct scsi_sense_hdr sshdr;
1743
	struct scsi_device *sdp = sdkp->device;
1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754
	int res;

	if (start)
		cmd[4] |= 1;	/* START */

	if (!scsi_device_online(sdp))
		return -ENODEV;

	res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr,
			       SD_TIMEOUT, SD_MAX_RETRIES);
	if (res) {
1755 1756
		sd_printk(KERN_WARNING, sdkp, "START_STOP FAILED\n");
		sd_print_result(sdkp, res);
1757
		if (driver_byte(res) & DRIVER_SENSE)
1758
			sd_print_sense_hdr(sdkp, &sshdr);
1759 1760 1761 1762 1763
	}

	return res;
}

L
Linus Torvalds 已提交
1764 1765 1766 1767 1768 1769 1770
/*
 * Send a SYNCHRONIZE CACHE instruction down to the device through
 * the normal SCSI command structure.  Wait for the command to
 * complete.
 */
static void sd_shutdown(struct device *dev)
{
A
Alan Stern 已提交
1771
	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
L
Linus Torvalds 已提交
1772 1773 1774 1775

	if (!sdkp)
		return;         /* this can happen */

A
Alan Stern 已提交
1776
	if (sdkp->WCE) {
1777 1778
		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
		sd_sync_cache(sdkp);
A
Alan Stern 已提交
1779
	}
1780

1781 1782 1783
	if (system_state != SYSTEM_RESTART && sdkp->device->manage_start_stop) {
		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
		sd_start_stop_device(sdkp, 0);
1784 1785
	}

A
Alan Stern 已提交
1786 1787
	scsi_disk_put(sdkp);
}
L
Linus Torvalds 已提交
1788

1789 1790 1791
static int sd_suspend(struct device *dev, pm_message_t mesg)
{
	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
1792
	int ret = 0;
1793 1794 1795 1796 1797

	if (!sdkp)
		return 0;	/* this can happen */

	if (sdkp->WCE) {
1798
		sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
1799 1800
		ret = sd_sync_cache(sdkp);
		if (ret)
1801
			goto done;
1802 1803
	}

1804 1805 1806 1807
	if (mesg.event == PM_EVENT_SUSPEND &&
	    sdkp->device->manage_start_stop) {
		sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
		ret = sd_start_stop_device(sdkp, 0);
1808 1809
	}

1810 1811 1812
done:
	scsi_disk_put(sdkp);
	return ret;
1813 1814 1815 1816 1817
}

static int sd_resume(struct device *dev)
{
	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
1818
	int ret = 0;
1819

1820
	if (!sdkp->device->manage_start_stop)
1821
		goto done;
1822

1823
	sd_printk(KERN_NOTICE, sdkp, "Starting disk\n");
1824
	ret = sd_start_stop_device(sdkp, 1);
1825

1826 1827 1828
done:
	scsi_disk_put(sdkp);
	return ret;
1829 1830
}

L
Linus Torvalds 已提交
1831 1832 1833 1834 1835 1836 1837 1838
/**
 *	init_sd - entry point for this driver (both when built in or when
 *	a module).
 *
 *	Note: this function registers this driver with the scsi mid-level.
 **/
static int __init init_sd(void)
{
1839
	int majors = 0, i, err;
L
Linus Torvalds 已提交
1840 1841 1842 1843 1844 1845 1846 1847 1848 1849

	SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));

	for (i = 0; i < SD_MAJORS; i++)
		if (register_blkdev(sd_major(i), "sd") == 0)
			majors++;

	if (!majors)
		return -ENODEV;

1850 1851 1852
	err = class_register(&sd_disk_class);
	if (err)
		goto err_out;
1853

1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865
	err = scsi_register_driver(&sd_template.gendrv);
	if (err)
		goto err_out_class;

	return 0;

err_out_class:
	class_unregister(&sd_disk_class);
err_out:
	for (i = 0; i < SD_MAJORS; i++)
		unregister_blkdev(sd_major(i), "sd");
	return err;
L
Linus Torvalds 已提交
1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879
}

/**
 *	exit_sd - exit point for this driver (when it is a module).
 *
 *	Note: this function unregisters this driver from the scsi mid-level.
 **/
static void __exit exit_sd(void)
{
	int i;

	SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n"));

	scsi_unregister_driver(&sd_template.gendrv);
1880 1881
	class_unregister(&sd_disk_class);

L
Linus Torvalds 已提交
1882 1883 1884 1885 1886 1887
	for (i = 0; i < SD_MAJORS; i++)
		unregister_blkdev(sd_major(i), "sd");
}

module_init(init_sd);
module_exit(exit_sd);
1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903

static void sd_print_sense_hdr(struct scsi_disk *sdkp,
			       struct scsi_sense_hdr *sshdr)
{
	sd_printk(KERN_INFO, sdkp, "");
	scsi_show_sense_hdr(sshdr);
	sd_printk(KERN_INFO, sdkp, "");
	scsi_show_extd_sense(sshdr->asc, sshdr->ascq);
}

static void sd_print_result(struct scsi_disk *sdkp, int result)
{
	sd_printk(KERN_INFO, sdkp, "");
	scsi_show_result(result);
}