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/sched.h> 39 #include <linux/mm.h> 40 #include <linux/bio.h> 41 #include <linux/genhd.h> 42 #include <linux/hdreg.h> 43 #include <linux/errno.h> 44 #include <linux/idr.h> 45 #include <linux/interrupt.h> 46 #include <linux/init.h> 47 #include <linux/blkdev.h> 48 #include <linux/blkpg.h> 49 #include <linux/delay.h> 50 #include <linux/mutex.h> 51 #include <asm/uaccess.h> 52 53 #include <scsi/scsi.h> 54 #include <scsi/scsi_cmnd.h> 55 #include <scsi/scsi_dbg.h> 56 #include <scsi/scsi_device.h> 57 #include <scsi/scsi_driver.h> 58 #include <scsi/scsi_eh.h> 59 #include <scsi/scsi_host.h> 60 #include <scsi/scsi_ioctl.h> 61 #include <scsi/scsicam.h> 62 63 #include "scsi_logging.h" 64 65 /* 66 * More than enough for everybody ;) The huge number of majors 67 * is a leftover from 16bit dev_t days, we don't really need that 68 * much numberspace. 69 */ 70 #define SD_MAJORS 16 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 93 /* 94 * This is limited by the naming scheme enforced in sd_probe, 95 * add another character to it if you really need more disks. 96 */ 97 #define SD_MAX_DISKS (((26 * 26) + 26 + 1) * 26) 98 99 /* 100 * Time out in seconds for disks and Magneto-opticals (which are slower). 101 */ 102 #define SD_TIMEOUT (30 * HZ) 103 #define SD_MOD_TIMEOUT (75 * HZ) 104 105 /* 106 * Number of allowed retries 107 */ 108 #define SD_MAX_RETRIES 5 109 #define SD_PASSTHROUGH_RETRIES 1 110 111 /* 112 * Size of the initial data buffer for mode and read capacity data 113 */ 114 #define SD_BUF_SIZE 512 115 116 struct scsi_disk { 117 struct scsi_driver *driver; /* always &sd_template */ 118 struct scsi_device *device; 119 struct class_device cdev; 120 struct gendisk *disk; 121 unsigned int openers; /* protected by BKL for now, yuck */ 122 sector_t capacity; /* size in 512-byte sectors */ 123 u32 index; 124 u8 media_present; 125 u8 write_prot; 126 unsigned WCE : 1; /* state of disk WCE bit */ 127 unsigned RCD : 1; /* state of disk RCD bit, unused */ 128 unsigned DPOFUA : 1; /* state of disk DPOFUA bit */ 129 }; 130 #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,cdev) 131 132 static DEFINE_IDR(sd_index_idr); 133 static DEFINE_SPINLOCK(sd_index_lock); 134 135 /* This semaphore is used to mediate the 0->1 reference get in the 136 * face of object destruction (i.e. we can't allow a get on an 137 * object after last put) */ 138 static DEFINE_MUTEX(sd_ref_mutex); 139 140 static int sd_revalidate_disk(struct gendisk *disk); 141 static void sd_rw_intr(struct scsi_cmnd * SCpnt); 142 143 static int sd_probe(struct device *); 144 static int sd_remove(struct device *); 145 static void sd_shutdown(struct device *dev); 146 static void sd_rescan(struct device *); 147 static int sd_init_command(struct scsi_cmnd *); 148 static int sd_issue_flush(struct device *, sector_t *); 149 static void sd_prepare_flush(request_queue_t *, struct request *); 150 static void sd_read_capacity(struct scsi_disk *sdkp, char *diskname, 151 unsigned char *buffer); 152 static void scsi_disk_release(struct class_device *cdev); 153 154 static const char *sd_cache_types[] = { 155 "write through", "none", "write back", 156 "write back, no read (daft)" 157 }; 158 159 static ssize_t sd_store_cache_type(struct class_device *cdev, const char *buf, 160 size_t count) 161 { 162 int i, ct = -1, rcd, wce, sp; 163 struct scsi_disk *sdkp = to_scsi_disk(cdev); 164 struct scsi_device *sdp = sdkp->device; 165 char buffer[64]; 166 char *buffer_data; 167 struct scsi_mode_data data; 168 struct scsi_sense_hdr sshdr; 169 int len; 170 171 if (sdp->type != TYPE_DISK) 172 /* no cache control on RBC devices; theoretically they 173 * can do it, but there's probably so many exceptions 174 * it's not worth the risk */ 175 return -EINVAL; 176 177 for (i = 0; i < ARRAY_SIZE(sd_cache_types); i++) { 178 const int len = strlen(sd_cache_types[i]); 179 if (strncmp(sd_cache_types[i], buf, len) == 0 && 180 buf[len] == '\n') { 181 ct = i; 182 break; 183 } 184 } 185 if (ct < 0) 186 return -EINVAL; 187 rcd = ct & 0x01 ? 1 : 0; 188 wce = ct & 0x02 ? 1 : 0; 189 if (scsi_mode_sense(sdp, 0x08, 8, buffer, sizeof(buffer), SD_TIMEOUT, 190 SD_MAX_RETRIES, &data, NULL)) 191 return -EINVAL; 192 len = min_t(size_t, sizeof(buffer), data.length - data.header_length - 193 data.block_descriptor_length); 194 buffer_data = buffer + data.header_length + 195 data.block_descriptor_length; 196 buffer_data[2] &= ~0x05; 197 buffer_data[2] |= wce << 2 | rcd; 198 sp = buffer_data[0] & 0x80 ? 1 : 0; 199 200 if (scsi_mode_select(sdp, 1, sp, 8, buffer_data, len, SD_TIMEOUT, 201 SD_MAX_RETRIES, &data, &sshdr)) { 202 if (scsi_sense_valid(&sshdr)) 203 scsi_print_sense_hdr(sdkp->disk->disk_name, &sshdr); 204 return -EINVAL; 205 } 206 sd_revalidate_disk(sdkp->disk); 207 return count; 208 } 209 210 static ssize_t sd_store_allow_restart(struct class_device *cdev, const char *buf, 211 size_t count) 212 { 213 struct scsi_disk *sdkp = to_scsi_disk(cdev); 214 struct scsi_device *sdp = sdkp->device; 215 216 if (!capable(CAP_SYS_ADMIN)) 217 return -EACCES; 218 219 if (sdp->type != TYPE_DISK) 220 return -EINVAL; 221 222 sdp->allow_restart = simple_strtoul(buf, NULL, 10); 223 224 return count; 225 } 226 227 static ssize_t sd_show_cache_type(struct class_device *cdev, char *buf) 228 { 229 struct scsi_disk *sdkp = to_scsi_disk(cdev); 230 int ct = sdkp->RCD + 2*sdkp->WCE; 231 232 return snprintf(buf, 40, "%s\n", sd_cache_types[ct]); 233 } 234 235 static ssize_t sd_show_fua(struct class_device *cdev, char *buf) 236 { 237 struct scsi_disk *sdkp = to_scsi_disk(cdev); 238 239 return snprintf(buf, 20, "%u\n", sdkp->DPOFUA); 240 } 241 242 static ssize_t sd_show_allow_restart(struct class_device *cdev, char *buf) 243 { 244 struct scsi_disk *sdkp = to_scsi_disk(cdev); 245 246 return snprintf(buf, 40, "%d\n", sdkp->device->allow_restart); 247 } 248 249 static struct class_device_attribute sd_disk_attrs[] = { 250 __ATTR(cache_type, S_IRUGO|S_IWUSR, sd_show_cache_type, 251 sd_store_cache_type), 252 __ATTR(FUA, S_IRUGO, sd_show_fua, NULL), 253 __ATTR(allow_restart, S_IRUGO|S_IWUSR, sd_show_allow_restart, 254 sd_store_allow_restart), 255 __ATTR_NULL, 256 }; 257 258 static struct class sd_disk_class = { 259 .name = "scsi_disk", 260 .owner = THIS_MODULE, 261 .release = scsi_disk_release, 262 .class_dev_attrs = sd_disk_attrs, 263 }; 264 265 static struct scsi_driver sd_template = { 266 .owner = THIS_MODULE, 267 .gendrv = { 268 .name = "sd", 269 .probe = sd_probe, 270 .remove = sd_remove, 271 .shutdown = sd_shutdown, 272 }, 273 .rescan = sd_rescan, 274 .init_command = sd_init_command, 275 .issue_flush = sd_issue_flush, 276 }; 277 278 /* 279 * Device no to disk mapping: 280 * 281 * major disc2 disc p1 282 * |............|.............|....|....| <- dev_t 283 * 31 20 19 8 7 4 3 0 284 * 285 * Inside a major, we have 16k disks, however mapped non- 286 * contiguously. The first 16 disks are for major0, the next 287 * ones with major1, ... Disk 256 is for major0 again, disk 272 288 * for major1, ... 289 * As we stay compatible with our numbering scheme, we can reuse 290 * the well-know SCSI majors 8, 65--71, 136--143. 291 */ 292 static int sd_major(int major_idx) 293 { 294 switch (major_idx) { 295 case 0: 296 return SCSI_DISK0_MAJOR; 297 case 1 ... 7: 298 return SCSI_DISK1_MAJOR + major_idx - 1; 299 case 8 ... 15: 300 return SCSI_DISK8_MAJOR + major_idx - 8; 301 default: 302 BUG(); 303 return 0; /* shut up gcc */ 304 } 305 } 306 307 static inline struct scsi_disk *scsi_disk(struct gendisk *disk) 308 { 309 return container_of(disk->private_data, struct scsi_disk, driver); 310 } 311 312 static struct scsi_disk *__scsi_disk_get(struct gendisk *disk) 313 { 314 struct scsi_disk *sdkp = NULL; 315 316 if (disk->private_data) { 317 sdkp = scsi_disk(disk); 318 if (scsi_device_get(sdkp->device) == 0) 319 class_device_get(&sdkp->cdev); 320 else 321 sdkp = NULL; 322 } 323 return sdkp; 324 } 325 326 static struct scsi_disk *scsi_disk_get(struct gendisk *disk) 327 { 328 struct scsi_disk *sdkp; 329 330 mutex_lock(&sd_ref_mutex); 331 sdkp = __scsi_disk_get(disk); 332 mutex_unlock(&sd_ref_mutex); 333 return sdkp; 334 } 335 336 static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev) 337 { 338 struct scsi_disk *sdkp; 339 340 mutex_lock(&sd_ref_mutex); 341 sdkp = dev_get_drvdata(dev); 342 if (sdkp) 343 sdkp = __scsi_disk_get(sdkp->disk); 344 mutex_unlock(&sd_ref_mutex); 345 return sdkp; 346 } 347 348 static void scsi_disk_put(struct scsi_disk *sdkp) 349 { 350 struct scsi_device *sdev = sdkp->device; 351 352 mutex_lock(&sd_ref_mutex); 353 class_device_put(&sdkp->cdev); 354 scsi_device_put(sdev); 355 mutex_unlock(&sd_ref_mutex); 356 } 357 358 /** 359 * sd_init_command - build a scsi (read or write) command from 360 * information in the request structure. 361 * @SCpnt: pointer to mid-level's per scsi command structure that 362 * contains request and into which the scsi command is written 363 * 364 * Returns 1 if successful and 0 if error (or cannot be done now). 365 **/ 366 static int sd_init_command(struct scsi_cmnd * SCpnt) 367 { 368 struct scsi_device *sdp = SCpnt->device; 369 struct request *rq = SCpnt->request; 370 struct gendisk *disk = rq->rq_disk; 371 sector_t block = rq->sector; 372 unsigned int this_count = SCpnt->request_bufflen >> 9; 373 unsigned int timeout = sdp->timeout; 374 375 SCSI_LOG_HLQUEUE(1, printk("sd_init_command: disk=%s, block=%llu, " 376 "count=%d\n", disk->disk_name, 377 (unsigned long long)block, this_count)); 378 379 if (!sdp || !scsi_device_online(sdp) || 380 block + rq->nr_sectors > get_capacity(disk)) { 381 SCSI_LOG_HLQUEUE(2, printk("Finishing %ld sectors\n", 382 rq->nr_sectors)); 383 SCSI_LOG_HLQUEUE(2, printk("Retry with 0x%p\n", SCpnt)); 384 return 0; 385 } 386 387 if (sdp->changed) { 388 /* 389 * quietly refuse to do anything to a changed disc until 390 * the changed bit has been reset 391 */ 392 /* printk("SCSI disk has been changed. Prohibiting further I/O.\n"); */ 393 return 0; 394 } 395 SCSI_LOG_HLQUEUE(2, printk("%s : block=%llu\n", 396 disk->disk_name, (unsigned long long)block)); 397 398 /* 399 * If we have a 1K hardware sectorsize, prevent access to single 400 * 512 byte sectors. In theory we could handle this - in fact 401 * the scsi cdrom driver must be able to handle this because 402 * we typically use 1K blocksizes, and cdroms typically have 403 * 2K hardware sectorsizes. Of course, things are simpler 404 * with the cdrom, since it is read-only. For performance 405 * reasons, the filesystems should be able to handle this 406 * and not force the scsi disk driver to use bounce buffers 407 * for this. 408 */ 409 if (sdp->sector_size == 1024) { 410 if ((block & 1) || (rq->nr_sectors & 1)) { 411 printk(KERN_ERR "sd: Bad block number requested"); 412 return 0; 413 } else { 414 block = block >> 1; 415 this_count = this_count >> 1; 416 } 417 } 418 if (sdp->sector_size == 2048) { 419 if ((block & 3) || (rq->nr_sectors & 3)) { 420 printk(KERN_ERR "sd: Bad block number requested"); 421 return 0; 422 } else { 423 block = block >> 2; 424 this_count = this_count >> 2; 425 } 426 } 427 if (sdp->sector_size == 4096) { 428 if ((block & 7) || (rq->nr_sectors & 7)) { 429 printk(KERN_ERR "sd: Bad block number requested"); 430 return 0; 431 } else { 432 block = block >> 3; 433 this_count = this_count >> 3; 434 } 435 } 436 if (rq_data_dir(rq) == WRITE) { 437 if (!sdp->writeable) { 438 return 0; 439 } 440 SCpnt->cmnd[0] = WRITE_6; 441 SCpnt->sc_data_direction = DMA_TO_DEVICE; 442 } else if (rq_data_dir(rq) == READ) { 443 SCpnt->cmnd[0] = READ_6; 444 SCpnt->sc_data_direction = DMA_FROM_DEVICE; 445 } else { 446 printk(KERN_ERR "sd: Unknown command %lx\n", rq->flags); 447 /* overkill panic("Unknown sd command %lx\n", rq->flags); */ 448 return 0; 449 } 450 451 SCSI_LOG_HLQUEUE(2, printk("%s : %s %d/%ld 512 byte blocks.\n", 452 disk->disk_name, (rq_data_dir(rq) == WRITE) ? 453 "writing" : "reading", this_count, rq->nr_sectors)); 454 455 SCpnt->cmnd[1] = 0; 456 457 if (block > 0xffffffff) { 458 SCpnt->cmnd[0] += READ_16 - READ_6; 459 SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0; 460 SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0; 461 SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0; 462 SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0; 463 SCpnt->cmnd[5] = sizeof(block) > 4 ? (unsigned char) (block >> 32) & 0xff : 0; 464 SCpnt->cmnd[6] = (unsigned char) (block >> 24) & 0xff; 465 SCpnt->cmnd[7] = (unsigned char) (block >> 16) & 0xff; 466 SCpnt->cmnd[8] = (unsigned char) (block >> 8) & 0xff; 467 SCpnt->cmnd[9] = (unsigned char) block & 0xff; 468 SCpnt->cmnd[10] = (unsigned char) (this_count >> 24) & 0xff; 469 SCpnt->cmnd[11] = (unsigned char) (this_count >> 16) & 0xff; 470 SCpnt->cmnd[12] = (unsigned char) (this_count >> 8) & 0xff; 471 SCpnt->cmnd[13] = (unsigned char) this_count & 0xff; 472 SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0; 473 } else if ((this_count > 0xff) || (block > 0x1fffff) || 474 SCpnt->device->use_10_for_rw) { 475 if (this_count > 0xffff) 476 this_count = 0xffff; 477 478 SCpnt->cmnd[0] += READ_10 - READ_6; 479 SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0; 480 SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff; 481 SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff; 482 SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff; 483 SCpnt->cmnd[5] = (unsigned char) block & 0xff; 484 SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0; 485 SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff; 486 SCpnt->cmnd[8] = (unsigned char) this_count & 0xff; 487 } else { 488 if (unlikely(blk_fua_rq(rq))) { 489 /* 490 * This happens only if this drive failed 491 * 10byte rw command with ILLEGAL_REQUEST 492 * during operation and thus turned off 493 * use_10_for_rw. 494 */ 495 printk(KERN_ERR "sd: FUA write on READ/WRITE(6) drive\n"); 496 return 0; 497 } 498 499 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f); 500 SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff); 501 SCpnt->cmnd[3] = (unsigned char) block & 0xff; 502 SCpnt->cmnd[4] = (unsigned char) this_count; 503 SCpnt->cmnd[5] = 0; 504 } 505 SCpnt->request_bufflen = SCpnt->bufflen = 506 this_count * sdp->sector_size; 507 508 /* 509 * We shouldn't disconnect in the middle of a sector, so with a dumb 510 * host adapter, it's safe to assume that we can at least transfer 511 * this many bytes between each connect / disconnect. 512 */ 513 SCpnt->transfersize = sdp->sector_size; 514 SCpnt->underflow = this_count << 9; 515 SCpnt->allowed = SD_MAX_RETRIES; 516 SCpnt->timeout_per_command = timeout; 517 518 /* 519 * This is the completion routine we use. This is matched in terms 520 * of capability to this function. 521 */ 522 SCpnt->done = sd_rw_intr; 523 524 /* 525 * This indicates that the command is ready from our end to be 526 * queued. 527 */ 528 return 1; 529 } 530 531 /** 532 * sd_open - open a scsi disk device 533 * @inode: only i_rdev member may be used 534 * @filp: only f_mode and f_flags may be used 535 * 536 * Returns 0 if successful. Returns a negated errno value in case 537 * of error. 538 * 539 * Note: This can be called from a user context (e.g. fsck(1) ) 540 * or from within the kernel (e.g. as a result of a mount(1) ). 541 * In the latter case @inode and @filp carry an abridged amount 542 * of information as noted above. 543 **/ 544 static int sd_open(struct inode *inode, struct file *filp) 545 { 546 struct gendisk *disk = inode->i_bdev->bd_disk; 547 struct scsi_disk *sdkp; 548 struct scsi_device *sdev; 549 int retval; 550 551 if (!(sdkp = scsi_disk_get(disk))) 552 return -ENXIO; 553 554 555 SCSI_LOG_HLQUEUE(3, printk("sd_open: disk=%s\n", disk->disk_name)); 556 557 sdev = sdkp->device; 558 559 /* 560 * If the device is in error recovery, wait until it is done. 561 * If the device is offline, then disallow any access to it. 562 */ 563 retval = -ENXIO; 564 if (!scsi_block_when_processing_errors(sdev)) 565 goto error_out; 566 567 if (sdev->removable || sdkp->write_prot) 568 check_disk_change(inode->i_bdev); 569 570 /* 571 * If the drive is empty, just let the open fail. 572 */ 573 retval = -ENOMEDIUM; 574 if (sdev->removable && !sdkp->media_present && 575 !(filp->f_flags & O_NDELAY)) 576 goto error_out; 577 578 /* 579 * If the device has the write protect tab set, have the open fail 580 * if the user expects to be able to write to the thing. 581 */ 582 retval = -EROFS; 583 if (sdkp->write_prot && (filp->f_mode & FMODE_WRITE)) 584 goto error_out; 585 586 /* 587 * It is possible that the disk changing stuff resulted in 588 * the device being taken offline. If this is the case, 589 * report this to the user, and don't pretend that the 590 * open actually succeeded. 591 */ 592 retval = -ENXIO; 593 if (!scsi_device_online(sdev)) 594 goto error_out; 595 596 if (!sdkp->openers++ && sdev->removable) { 597 if (scsi_block_when_processing_errors(sdev)) 598 scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT); 599 } 600 601 return 0; 602 603 error_out: 604 scsi_disk_put(sdkp); 605 return retval; 606 } 607 608 /** 609 * sd_release - invoked when the (last) close(2) is called on this 610 * scsi disk. 611 * @inode: only i_rdev member may be used 612 * @filp: only f_mode and f_flags may be used 613 * 614 * Returns 0. 615 * 616 * Note: may block (uninterruptible) if error recovery is underway 617 * on this disk. 618 **/ 619 static int sd_release(struct inode *inode, struct file *filp) 620 { 621 struct gendisk *disk = inode->i_bdev->bd_disk; 622 struct scsi_disk *sdkp = scsi_disk(disk); 623 struct scsi_device *sdev = sdkp->device; 624 625 SCSI_LOG_HLQUEUE(3, printk("sd_release: disk=%s\n", disk->disk_name)); 626 627 if (!--sdkp->openers && sdev->removable) { 628 if (scsi_block_when_processing_errors(sdev)) 629 scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW); 630 } 631 632 /* 633 * XXX and what if there are packets in flight and this close() 634 * XXX is followed by a "rmmod sd_mod"? 635 */ 636 scsi_disk_put(sdkp); 637 return 0; 638 } 639 640 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 641 { 642 struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk); 643 struct scsi_device *sdp = sdkp->device; 644 struct Scsi_Host *host = sdp->host; 645 int diskinfo[4]; 646 647 /* default to most commonly used values */ 648 diskinfo[0] = 0x40; /* 1 << 6 */ 649 diskinfo[1] = 0x20; /* 1 << 5 */ 650 diskinfo[2] = sdkp->capacity >> 11; 651 652 /* override with calculated, extended default, or driver values */ 653 if (host->hostt->bios_param) 654 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo); 655 else 656 scsicam_bios_param(bdev, sdkp->capacity, diskinfo); 657 658 geo->heads = diskinfo[0]; 659 geo->sectors = diskinfo[1]; 660 geo->cylinders = diskinfo[2]; 661 return 0; 662 } 663 664 /** 665 * sd_ioctl - process an ioctl 666 * @inode: only i_rdev/i_bdev members may be used 667 * @filp: only f_mode and f_flags may be used 668 * @cmd: ioctl command number 669 * @arg: this is third argument given to ioctl(2) system call. 670 * Often contains a pointer. 671 * 672 * Returns 0 if successful (some ioctls return postive numbers on 673 * success as well). Returns a negated errno value in case of error. 674 * 675 * Note: most ioctls are forward onto the block subsystem or further 676 * down in the scsi subsytem. 677 **/ 678 static int sd_ioctl(struct inode * inode, struct file * filp, 679 unsigned int cmd, unsigned long arg) 680 { 681 struct block_device *bdev = inode->i_bdev; 682 struct gendisk *disk = bdev->bd_disk; 683 struct scsi_device *sdp = scsi_disk(disk)->device; 684 void __user *p = (void __user *)arg; 685 int error; 686 687 SCSI_LOG_IOCTL(1, printk("sd_ioctl: disk=%s, cmd=0x%x\n", 688 disk->disk_name, cmd)); 689 690 /* 691 * If we are in the middle of error recovery, don't let anyone 692 * else try and use this device. Also, if error recovery fails, it 693 * may try and take the device offline, in which case all further 694 * access to the device is prohibited. 695 */ 696 error = scsi_nonblockable_ioctl(sdp, cmd, p, filp); 697 if (!scsi_block_when_processing_errors(sdp) || !error) 698 return error; 699 700 /* 701 * Send SCSI addressing ioctls directly to mid level, send other 702 * ioctls to block level and then onto mid level if they can't be 703 * resolved. 704 */ 705 switch (cmd) { 706 case SCSI_IOCTL_GET_IDLUN: 707 case SCSI_IOCTL_GET_BUS_NUMBER: 708 return scsi_ioctl(sdp, cmd, p); 709 default: 710 error = scsi_cmd_ioctl(filp, disk, cmd, p); 711 if (error != -ENOTTY) 712 return error; 713 } 714 return scsi_ioctl(sdp, cmd, p); 715 } 716 717 static void set_media_not_present(struct scsi_disk *sdkp) 718 { 719 sdkp->media_present = 0; 720 sdkp->capacity = 0; 721 sdkp->device->changed = 1; 722 } 723 724 /** 725 * sd_media_changed - check if our medium changed 726 * @disk: kernel device descriptor 727 * 728 * Returns 0 if not applicable or no change; 1 if change 729 * 730 * Note: this function is invoked from the block subsystem. 731 **/ 732 static int sd_media_changed(struct gendisk *disk) 733 { 734 struct scsi_disk *sdkp = scsi_disk(disk); 735 struct scsi_device *sdp = sdkp->device; 736 int retval; 737 738 SCSI_LOG_HLQUEUE(3, printk("sd_media_changed: disk=%s\n", 739 disk->disk_name)); 740 741 if (!sdp->removable) 742 return 0; 743 744 /* 745 * If the device is offline, don't send any commands - just pretend as 746 * if the command failed. If the device ever comes back online, we 747 * can deal with it then. It is only because of unrecoverable errors 748 * that we would ever take a device offline in the first place. 749 */ 750 if (!scsi_device_online(sdp)) 751 goto not_present; 752 753 /* 754 * Using TEST_UNIT_READY enables differentiation between drive with 755 * no cartridge loaded - NOT READY, drive with changed cartridge - 756 * UNIT ATTENTION, or with same cartridge - GOOD STATUS. 757 * 758 * Drives that auto spin down. eg iomega jaz 1G, will be started 759 * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever 760 * sd_revalidate() is called. 761 */ 762 retval = -ENODEV; 763 if (scsi_block_when_processing_errors(sdp)) 764 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES); 765 766 /* 767 * Unable to test, unit probably not ready. This usually 768 * means there is no disc in the drive. Mark as changed, 769 * and we will figure it out later once the drive is 770 * available again. 771 */ 772 if (retval) 773 goto not_present; 774 775 /* 776 * For removable scsi disk we have to recognise the presence 777 * of a disk in the drive. This is kept in the struct scsi_disk 778 * struct and tested at open ! Daniel Roche (dan@lectra.fr) 779 */ 780 sdkp->media_present = 1; 781 782 retval = sdp->changed; 783 sdp->changed = 0; 784 785 return retval; 786 787 not_present: 788 set_media_not_present(sdkp); 789 return 1; 790 } 791 792 static int sd_sync_cache(struct scsi_device *sdp) 793 { 794 int retries, res; 795 struct scsi_sense_hdr sshdr; 796 797 if (!scsi_device_online(sdp)) 798 return -ENODEV; 799 800 801 for (retries = 3; retries > 0; --retries) { 802 unsigned char cmd[10] = { 0 }; 803 804 cmd[0] = SYNCHRONIZE_CACHE; 805 /* 806 * Leave the rest of the command zero to indicate 807 * flush everything. 808 */ 809 res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr, 810 SD_TIMEOUT, SD_MAX_RETRIES); 811 if (res == 0) 812 break; 813 } 814 815 if (res) { printk(KERN_WARNING "FAILED\n status = %x, message = %02x, " 816 "host = %d, driver = %02x\n ", 817 status_byte(res), msg_byte(res), 818 host_byte(res), driver_byte(res)); 819 if (driver_byte(res) & DRIVER_SENSE) 820 scsi_print_sense_hdr("sd", &sshdr); 821 } 822 823 return res; 824 } 825 826 static int sd_issue_flush(struct device *dev, sector_t *error_sector) 827 { 828 int ret = 0; 829 struct scsi_device *sdp = to_scsi_device(dev); 830 struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev); 831 832 if (!sdkp) 833 return -ENODEV; 834 835 if (sdkp->WCE) 836 ret = sd_sync_cache(sdp); 837 scsi_disk_put(sdkp); 838 return ret; 839 } 840 841 static void sd_prepare_flush(request_queue_t *q, struct request *rq) 842 { 843 memset(rq->cmd, 0, sizeof(rq->cmd)); 844 rq->flags |= REQ_BLOCK_PC; 845 rq->timeout = SD_TIMEOUT; 846 rq->cmd[0] = SYNCHRONIZE_CACHE; 847 rq->cmd_len = 10; 848 } 849 850 static void sd_rescan(struct device *dev) 851 { 852 struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev); 853 854 if (sdkp) { 855 sd_revalidate_disk(sdkp->disk); 856 scsi_disk_put(sdkp); 857 } 858 } 859 860 861 #ifdef CONFIG_COMPAT 862 /* 863 * This gets directly called from VFS. When the ioctl 864 * is not recognized we go back to the other translation paths. 865 */ 866 static long sd_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 867 { 868 struct block_device *bdev = file->f_dentry->d_inode->i_bdev; 869 struct gendisk *disk = bdev->bd_disk; 870 struct scsi_device *sdev = scsi_disk(disk)->device; 871 872 /* 873 * If we are in the middle of error recovery, don't let anyone 874 * else try and use this device. Also, if error recovery fails, it 875 * may try and take the device offline, in which case all further 876 * access to the device is prohibited. 877 */ 878 if (!scsi_block_when_processing_errors(sdev)) 879 return -ENODEV; 880 881 if (sdev->host->hostt->compat_ioctl) { 882 int ret; 883 884 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg); 885 886 return ret; 887 } 888 889 /* 890 * Let the static ioctl translation table take care of it. 891 */ 892 return -ENOIOCTLCMD; 893 } 894 #endif 895 896 static struct block_device_operations sd_fops = { 897 .owner = THIS_MODULE, 898 .open = sd_open, 899 .release = sd_release, 900 .ioctl = sd_ioctl, 901 .getgeo = sd_getgeo, 902 #ifdef CONFIG_COMPAT 903 .compat_ioctl = sd_compat_ioctl, 904 #endif 905 .media_changed = sd_media_changed, 906 .revalidate_disk = sd_revalidate_disk, 907 }; 908 909 /** 910 * sd_rw_intr - bottom half handler: called when the lower level 911 * driver has completed (successfully or otherwise) a scsi command. 912 * @SCpnt: mid-level's per command structure. 913 * 914 * Note: potentially run from within an ISR. Must not block. 915 **/ 916 static void sd_rw_intr(struct scsi_cmnd * SCpnt) 917 { 918 int result = SCpnt->result; 919 unsigned int xfer_size = SCpnt->request_bufflen; 920 unsigned int good_bytes = result ? 0 : xfer_size; 921 u64 start_lba = SCpnt->request->sector; 922 u64 bad_lba; 923 struct scsi_sense_hdr sshdr; 924 int sense_valid = 0; 925 int sense_deferred = 0; 926 int info_valid; 927 928 if (result) { 929 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr); 930 if (sense_valid) 931 sense_deferred = scsi_sense_is_deferred(&sshdr); 932 } 933 #ifdef CONFIG_SCSI_LOGGING 934 SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: %s: res=0x%x\n", 935 SCpnt->request->rq_disk->disk_name, result)); 936 if (sense_valid) { 937 SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: sb[respc,sk,asc," 938 "ascq]=%x,%x,%x,%x\n", sshdr.response_code, 939 sshdr.sense_key, sshdr.asc, sshdr.ascq)); 940 } 941 #endif 942 if (driver_byte(result) != DRIVER_SENSE && 943 (!sense_valid || sense_deferred)) 944 goto out; 945 946 switch (sshdr.sense_key) { 947 case HARDWARE_ERROR: 948 case MEDIUM_ERROR: 949 if (!blk_fs_request(SCpnt->request)) 950 goto out; 951 info_valid = scsi_get_sense_info_fld(SCpnt->sense_buffer, 952 SCSI_SENSE_BUFFERSIZE, 953 &bad_lba); 954 if (!info_valid) 955 goto out; 956 if (xfer_size <= SCpnt->device->sector_size) 957 goto out; 958 switch (SCpnt->device->sector_size) { 959 case 256: 960 start_lba <<= 1; 961 break; 962 case 512: 963 break; 964 case 1024: 965 start_lba >>= 1; 966 break; 967 case 2048: 968 start_lba >>= 2; 969 break; 970 case 4096: 971 start_lba >>= 3; 972 break; 973 default: 974 /* Print something here with limiting frequency. */ 975 goto out; 976 break; 977 } 978 /* This computation should always be done in terms of 979 * the resolution of the device's medium. 980 */ 981 good_bytes = (bad_lba - start_lba)*SCpnt->device->sector_size; 982 break; 983 case RECOVERED_ERROR: 984 case NO_SENSE: 985 /* Inform the user, but make sure that it's not treated 986 * as a hard error. 987 */ 988 scsi_print_sense("sd", SCpnt); 989 SCpnt->result = 0; 990 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); 991 good_bytes = xfer_size; 992 break; 993 case ILLEGAL_REQUEST: 994 if (SCpnt->device->use_10_for_rw && 995 (SCpnt->cmnd[0] == READ_10 || 996 SCpnt->cmnd[0] == WRITE_10)) 997 SCpnt->device->use_10_for_rw = 0; 998 if (SCpnt->device->use_10_for_ms && 999 (SCpnt->cmnd[0] == MODE_SENSE_10 || 1000 SCpnt->cmnd[0] == MODE_SELECT_10)) 1001 SCpnt->device->use_10_for_ms = 0; 1002 break; 1003 default: 1004 break; 1005 } 1006 out: 1007 scsi_io_completion(SCpnt, good_bytes); 1008 } 1009 1010 static int media_not_present(struct scsi_disk *sdkp, 1011 struct scsi_sense_hdr *sshdr) 1012 { 1013 1014 if (!scsi_sense_valid(sshdr)) 1015 return 0; 1016 /* not invoked for commands that could return deferred errors */ 1017 if (sshdr->sense_key != NOT_READY && 1018 sshdr->sense_key != UNIT_ATTENTION) 1019 return 0; 1020 if (sshdr->asc != 0x3A) /* medium not present */ 1021 return 0; 1022 1023 set_media_not_present(sdkp); 1024 return 1; 1025 } 1026 1027 /* 1028 * spinup disk - called only in sd_revalidate_disk() 1029 */ 1030 static void 1031 sd_spinup_disk(struct scsi_disk *sdkp, char *diskname) 1032 { 1033 unsigned char cmd[10]; 1034 unsigned long spintime_expire = 0; 1035 int retries, spintime; 1036 unsigned int the_result; 1037 struct scsi_sense_hdr sshdr; 1038 int sense_valid = 0; 1039 1040 spintime = 0; 1041 1042 /* Spin up drives, as required. Only do this at boot time */ 1043 /* Spinup needs to be done for module loads too. */ 1044 do { 1045 retries = 0; 1046 1047 do { 1048 cmd[0] = TEST_UNIT_READY; 1049 memset((void *) &cmd[1], 0, 9); 1050 1051 the_result = scsi_execute_req(sdkp->device, cmd, 1052 DMA_NONE, NULL, 0, 1053 &sshdr, SD_TIMEOUT, 1054 SD_MAX_RETRIES); 1055 1056 if (the_result) 1057 sense_valid = scsi_sense_valid(&sshdr); 1058 retries++; 1059 } while (retries < 3 && 1060 (!scsi_status_is_good(the_result) || 1061 ((driver_byte(the_result) & DRIVER_SENSE) && 1062 sense_valid && sshdr.sense_key == UNIT_ATTENTION))); 1063 1064 /* 1065 * If the drive has indicated to us that it doesn't have 1066 * any media in it, don't bother with any of the rest of 1067 * this crap. 1068 */ 1069 if (media_not_present(sdkp, &sshdr)) 1070 return; 1071 1072 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) { 1073 /* no sense, TUR either succeeded or failed 1074 * with a status error */ 1075 if(!spintime && !scsi_status_is_good(the_result)) 1076 printk(KERN_NOTICE "%s: Unit Not Ready, " 1077 "error = 0x%x\n", diskname, the_result); 1078 break; 1079 } 1080 1081 /* 1082 * The device does not want the automatic start to be issued. 1083 */ 1084 if (sdkp->device->no_start_on_add) { 1085 break; 1086 } 1087 1088 /* 1089 * If manual intervention is required, or this is an 1090 * absent USB storage device, a spinup is meaningless. 1091 */ 1092 if (sense_valid && 1093 sshdr.sense_key == NOT_READY && 1094 sshdr.asc == 4 && sshdr.ascq == 3) { 1095 break; /* manual intervention required */ 1096 1097 /* 1098 * Issue command to spin up drive when not ready 1099 */ 1100 } else if (sense_valid && sshdr.sense_key == NOT_READY) { 1101 if (!spintime) { 1102 printk(KERN_NOTICE "%s: Spinning up disk...", 1103 diskname); 1104 cmd[0] = START_STOP; 1105 cmd[1] = 1; /* Return immediately */ 1106 memset((void *) &cmd[2], 0, 8); 1107 cmd[4] = 1; /* Start spin cycle */ 1108 scsi_execute_req(sdkp->device, cmd, DMA_NONE, 1109 NULL, 0, &sshdr, 1110 SD_TIMEOUT, SD_MAX_RETRIES); 1111 spintime_expire = jiffies + 100 * HZ; 1112 spintime = 1; 1113 } 1114 /* Wait 1 second for next try */ 1115 msleep(1000); 1116 printk("."); 1117 1118 /* 1119 * Wait for USB flash devices with slow firmware. 1120 * Yes, this sense key/ASC combination shouldn't 1121 * occur here. It's characteristic of these devices. 1122 */ 1123 } else if (sense_valid && 1124 sshdr.sense_key == UNIT_ATTENTION && 1125 sshdr.asc == 0x28) { 1126 if (!spintime) { 1127 spintime_expire = jiffies + 5 * HZ; 1128 spintime = 1; 1129 } 1130 /* Wait 1 second for next try */ 1131 msleep(1000); 1132 } else { 1133 /* we don't understand the sense code, so it's 1134 * probably pointless to loop */ 1135 if(!spintime) { 1136 printk(KERN_NOTICE "%s: Unit Not Ready, " 1137 "sense:\n", diskname); 1138 scsi_print_sense_hdr("", &sshdr); 1139 } 1140 break; 1141 } 1142 1143 } while (spintime && time_before_eq(jiffies, spintime_expire)); 1144 1145 if (spintime) { 1146 if (scsi_status_is_good(the_result)) 1147 printk("ready\n"); 1148 else 1149 printk("not responding...\n"); 1150 } 1151 } 1152 1153 /* 1154 * read disk capacity 1155 */ 1156 static void 1157 sd_read_capacity(struct scsi_disk *sdkp, char *diskname, 1158 unsigned char *buffer) 1159 { 1160 unsigned char cmd[16]; 1161 int the_result, retries; 1162 int sector_size = 0; 1163 int longrc = 0; 1164 struct scsi_sense_hdr sshdr; 1165 int sense_valid = 0; 1166 struct scsi_device *sdp = sdkp->device; 1167 1168 repeat: 1169 retries = 3; 1170 do { 1171 if (longrc) { 1172 memset((void *) cmd, 0, 16); 1173 cmd[0] = SERVICE_ACTION_IN; 1174 cmd[1] = SAI_READ_CAPACITY_16; 1175 cmd[13] = 12; 1176 memset((void *) buffer, 0, 12); 1177 } else { 1178 cmd[0] = READ_CAPACITY; 1179 memset((void *) &cmd[1], 0, 9); 1180 memset((void *) buffer, 0, 8); 1181 } 1182 1183 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE, 1184 buffer, longrc ? 12 : 8, &sshdr, 1185 SD_TIMEOUT, SD_MAX_RETRIES); 1186 1187 if (media_not_present(sdkp, &sshdr)) 1188 return; 1189 1190 if (the_result) 1191 sense_valid = scsi_sense_valid(&sshdr); 1192 retries--; 1193 1194 } while (the_result && retries); 1195 1196 if (the_result && !longrc) { 1197 printk(KERN_NOTICE "%s : READ CAPACITY failed.\n" 1198 "%s : status=%x, message=%02x, host=%d, driver=%02x \n", 1199 diskname, diskname, 1200 status_byte(the_result), 1201 msg_byte(the_result), 1202 host_byte(the_result), 1203 driver_byte(the_result)); 1204 1205 if (driver_byte(the_result) & DRIVER_SENSE) 1206 scsi_print_sense_hdr("sd", &sshdr); 1207 else 1208 printk("%s : sense not available. \n", diskname); 1209 1210 /* Set dirty bit for removable devices if not ready - 1211 * sometimes drives will not report this properly. */ 1212 if (sdp->removable && 1213 sense_valid && sshdr.sense_key == NOT_READY) 1214 sdp->changed = 1; 1215 1216 /* Either no media are present but the drive didn't tell us, 1217 or they are present but the read capacity command fails */ 1218 /* sdkp->media_present = 0; -- not always correct */ 1219 sdkp->capacity = 0x200000; /* 1 GB - random */ 1220 1221 return; 1222 } else if (the_result && longrc) { 1223 /* READ CAPACITY(16) has been failed */ 1224 printk(KERN_NOTICE "%s : READ CAPACITY(16) failed.\n" 1225 "%s : status=%x, message=%02x, host=%d, driver=%02x \n", 1226 diskname, diskname, 1227 status_byte(the_result), 1228 msg_byte(the_result), 1229 host_byte(the_result), 1230 driver_byte(the_result)); 1231 printk(KERN_NOTICE "%s : use 0xffffffff as device size\n", 1232 diskname); 1233 1234 sdkp->capacity = 1 + (sector_t) 0xffffffff; 1235 goto got_data; 1236 } 1237 1238 if (!longrc) { 1239 sector_size = (buffer[4] << 24) | 1240 (buffer[5] << 16) | (buffer[6] << 8) | buffer[7]; 1241 if (buffer[0] == 0xff && buffer[1] == 0xff && 1242 buffer[2] == 0xff && buffer[3] == 0xff) { 1243 if(sizeof(sdkp->capacity) > 4) { 1244 printk(KERN_NOTICE "%s : very big device. try to use" 1245 " READ CAPACITY(16).\n", diskname); 1246 longrc = 1; 1247 goto repeat; 1248 } 1249 printk(KERN_ERR "%s: too big for this kernel. Use a " 1250 "kernel compiled with support for large block " 1251 "devices.\n", diskname); 1252 sdkp->capacity = 0; 1253 goto got_data; 1254 } 1255 sdkp->capacity = 1 + (((sector_t)buffer[0] << 24) | 1256 (buffer[1] << 16) | 1257 (buffer[2] << 8) | 1258 buffer[3]); 1259 } else { 1260 sdkp->capacity = 1 + (((u64)buffer[0] << 56) | 1261 ((u64)buffer[1] << 48) | 1262 ((u64)buffer[2] << 40) | 1263 ((u64)buffer[3] << 32) | 1264 ((sector_t)buffer[4] << 24) | 1265 ((sector_t)buffer[5] << 16) | 1266 ((sector_t)buffer[6] << 8) | 1267 (sector_t)buffer[7]); 1268 1269 sector_size = (buffer[8] << 24) | 1270 (buffer[9] << 16) | (buffer[10] << 8) | buffer[11]; 1271 } 1272 1273 /* Some devices return the total number of sectors, not the 1274 * highest sector number. Make the necessary adjustment. */ 1275 if (sdp->fix_capacity) 1276 --sdkp->capacity; 1277 1278 got_data: 1279 if (sector_size == 0) { 1280 sector_size = 512; 1281 printk(KERN_NOTICE "%s : sector size 0 reported, " 1282 "assuming 512.\n", diskname); 1283 } 1284 1285 if (sector_size != 512 && 1286 sector_size != 1024 && 1287 sector_size != 2048 && 1288 sector_size != 4096 && 1289 sector_size != 256) { 1290 printk(KERN_NOTICE "%s : unsupported sector size " 1291 "%d.\n", diskname, sector_size); 1292 /* 1293 * The user might want to re-format the drive with 1294 * a supported sectorsize. Once this happens, it 1295 * would be relatively trivial to set the thing up. 1296 * For this reason, we leave the thing in the table. 1297 */ 1298 sdkp->capacity = 0; 1299 /* 1300 * set a bogus sector size so the normal read/write 1301 * logic in the block layer will eventually refuse any 1302 * request on this device without tripping over power 1303 * of two sector size assumptions 1304 */ 1305 sector_size = 512; 1306 } 1307 { 1308 /* 1309 * The msdos fs needs to know the hardware sector size 1310 * So I have created this table. See ll_rw_blk.c 1311 * Jacques Gelinas (Jacques@solucorp.qc.ca) 1312 */ 1313 int hard_sector = sector_size; 1314 sector_t sz = (sdkp->capacity/2) * (hard_sector/256); 1315 request_queue_t *queue = sdp->request_queue; 1316 sector_t mb = sz; 1317 1318 blk_queue_hardsect_size(queue, hard_sector); 1319 /* avoid 64-bit division on 32-bit platforms */ 1320 sector_div(sz, 625); 1321 mb -= sz - 974; 1322 sector_div(mb, 1950); 1323 1324 printk(KERN_NOTICE "SCSI device %s: " 1325 "%llu %d-byte hdwr sectors (%llu MB)\n", 1326 diskname, (unsigned long long)sdkp->capacity, 1327 hard_sector, (unsigned long long)mb); 1328 } 1329 1330 /* Rescale capacity to 512-byte units */ 1331 if (sector_size == 4096) 1332 sdkp->capacity <<= 3; 1333 else if (sector_size == 2048) 1334 sdkp->capacity <<= 2; 1335 else if (sector_size == 1024) 1336 sdkp->capacity <<= 1; 1337 else if (sector_size == 256) 1338 sdkp->capacity >>= 1; 1339 1340 sdkp->device->sector_size = sector_size; 1341 } 1342 1343 /* called with buffer of length 512 */ 1344 static inline int 1345 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage, 1346 unsigned char *buffer, int len, struct scsi_mode_data *data, 1347 struct scsi_sense_hdr *sshdr) 1348 { 1349 return scsi_mode_sense(sdp, dbd, modepage, buffer, len, 1350 SD_TIMEOUT, SD_MAX_RETRIES, data, 1351 sshdr); 1352 } 1353 1354 /* 1355 * read write protect setting, if possible - called only in sd_revalidate_disk() 1356 * called with buffer of length SD_BUF_SIZE 1357 */ 1358 static void 1359 sd_read_write_protect_flag(struct scsi_disk *sdkp, char *diskname, 1360 unsigned char *buffer) 1361 { 1362 int res; 1363 struct scsi_device *sdp = sdkp->device; 1364 struct scsi_mode_data data; 1365 1366 set_disk_ro(sdkp->disk, 0); 1367 if (sdp->skip_ms_page_3f) { 1368 printk(KERN_NOTICE "%s: assuming Write Enabled\n", diskname); 1369 return; 1370 } 1371 1372 if (sdp->use_192_bytes_for_3f) { 1373 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL); 1374 } else { 1375 /* 1376 * First attempt: ask for all pages (0x3F), but only 4 bytes. 1377 * We have to start carefully: some devices hang if we ask 1378 * for more than is available. 1379 */ 1380 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL); 1381 1382 /* 1383 * Second attempt: ask for page 0 When only page 0 is 1384 * implemented, a request for page 3F may return Sense Key 1385 * 5: Illegal Request, Sense Code 24: Invalid field in 1386 * CDB. 1387 */ 1388 if (!scsi_status_is_good(res)) 1389 res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL); 1390 1391 /* 1392 * Third attempt: ask 255 bytes, as we did earlier. 1393 */ 1394 if (!scsi_status_is_good(res)) 1395 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255, 1396 &data, NULL); 1397 } 1398 1399 if (!scsi_status_is_good(res)) { 1400 printk(KERN_WARNING 1401 "%s: test WP failed, assume Write Enabled\n", diskname); 1402 } else { 1403 sdkp->write_prot = ((data.device_specific & 0x80) != 0); 1404 set_disk_ro(sdkp->disk, sdkp->write_prot); 1405 printk(KERN_NOTICE "%s: Write Protect is %s\n", diskname, 1406 sdkp->write_prot ? "on" : "off"); 1407 printk(KERN_DEBUG "%s: Mode Sense: %02x %02x %02x %02x\n", 1408 diskname, buffer[0], buffer[1], buffer[2], buffer[3]); 1409 } 1410 } 1411 1412 /* 1413 * sd_read_cache_type - called only from sd_revalidate_disk() 1414 * called with buffer of length SD_BUF_SIZE 1415 */ 1416 static void 1417 sd_read_cache_type(struct scsi_disk *sdkp, char *diskname, 1418 unsigned char *buffer) 1419 { 1420 int len = 0, res; 1421 struct scsi_device *sdp = sdkp->device; 1422 1423 int dbd; 1424 int modepage; 1425 struct scsi_mode_data data; 1426 struct scsi_sense_hdr sshdr; 1427 1428 if (sdp->skip_ms_page_8) 1429 goto defaults; 1430 1431 if (sdp->type == TYPE_RBC) { 1432 modepage = 6; 1433 dbd = 8; 1434 } else { 1435 modepage = 8; 1436 dbd = 0; 1437 } 1438 1439 /* cautiously ask */ 1440 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, 4, &data, &sshdr); 1441 1442 if (!scsi_status_is_good(res)) 1443 goto bad_sense; 1444 1445 if (!data.header_length) { 1446 modepage = 6; 1447 printk(KERN_ERR "%s: missing header in MODE_SENSE response\n", 1448 diskname); 1449 } 1450 1451 /* that went OK, now ask for the proper length */ 1452 len = data.length; 1453 1454 /* 1455 * We're only interested in the first three bytes, actually. 1456 * But the data cache page is defined for the first 20. 1457 */ 1458 if (len < 3) 1459 goto bad_sense; 1460 if (len > 20) 1461 len = 20; 1462 1463 /* Take headers and block descriptors into account */ 1464 len += data.header_length + data.block_descriptor_length; 1465 if (len > SD_BUF_SIZE) 1466 goto bad_sense; 1467 1468 /* Get the data */ 1469 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len, &data, &sshdr); 1470 1471 if (scsi_status_is_good(res)) { 1472 int ct = 0; 1473 int offset = data.header_length + data.block_descriptor_length; 1474 1475 if (offset >= SD_BUF_SIZE - 2) { 1476 printk(KERN_ERR "%s: malformed MODE SENSE response", 1477 diskname); 1478 goto defaults; 1479 } 1480 1481 if ((buffer[offset] & 0x3f) != modepage) { 1482 printk(KERN_ERR "%s: got wrong page\n", diskname); 1483 goto defaults; 1484 } 1485 1486 if (modepage == 8) { 1487 sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0); 1488 sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0); 1489 } else { 1490 sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0); 1491 sdkp->RCD = 0; 1492 } 1493 1494 sdkp->DPOFUA = (data.device_specific & 0x10) != 0; 1495 if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) { 1496 printk(KERN_NOTICE "SCSI device %s: uses " 1497 "READ/WRITE(6), disabling FUA\n", diskname); 1498 sdkp->DPOFUA = 0; 1499 } 1500 1501 ct = sdkp->RCD + 2*sdkp->WCE; 1502 1503 printk(KERN_NOTICE "SCSI device %s: drive cache: %s%s\n", 1504 diskname, sd_cache_types[ct], 1505 sdkp->DPOFUA ? " w/ FUA" : ""); 1506 1507 return; 1508 } 1509 1510 bad_sense: 1511 if (scsi_sense_valid(&sshdr) && 1512 sshdr.sense_key == ILLEGAL_REQUEST && 1513 sshdr.asc == 0x24 && sshdr.ascq == 0x0) 1514 printk(KERN_NOTICE "%s: cache data unavailable\n", 1515 diskname); /* Invalid field in CDB */ 1516 else 1517 printk(KERN_ERR "%s: asking for cache data failed\n", 1518 diskname); 1519 1520 defaults: 1521 printk(KERN_ERR "%s: assuming drive cache: write through\n", 1522 diskname); 1523 sdkp->WCE = 0; 1524 sdkp->RCD = 0; 1525 sdkp->DPOFUA = 0; 1526 } 1527 1528 /** 1529 * sd_revalidate_disk - called the first time a new disk is seen, 1530 * performs disk spin up, read_capacity, etc. 1531 * @disk: struct gendisk we care about 1532 **/ 1533 static int sd_revalidate_disk(struct gendisk *disk) 1534 { 1535 struct scsi_disk *sdkp = scsi_disk(disk); 1536 struct scsi_device *sdp = sdkp->device; 1537 unsigned char *buffer; 1538 unsigned ordered; 1539 1540 SCSI_LOG_HLQUEUE(3, printk("sd_revalidate_disk: disk=%s\n", disk->disk_name)); 1541 1542 /* 1543 * If the device is offline, don't try and read capacity or any 1544 * of the other niceties. 1545 */ 1546 if (!scsi_device_online(sdp)) 1547 goto out; 1548 1549 buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL | __GFP_DMA); 1550 if (!buffer) { 1551 printk(KERN_WARNING "(sd_revalidate_disk:) Memory allocation " 1552 "failure.\n"); 1553 goto out; 1554 } 1555 1556 /* defaults, until the device tells us otherwise */ 1557 sdp->sector_size = 512; 1558 sdkp->capacity = 0; 1559 sdkp->media_present = 1; 1560 sdkp->write_prot = 0; 1561 sdkp->WCE = 0; 1562 sdkp->RCD = 0; 1563 1564 sd_spinup_disk(sdkp, disk->disk_name); 1565 1566 /* 1567 * Without media there is no reason to ask; moreover, some devices 1568 * react badly if we do. 1569 */ 1570 if (sdkp->media_present) { 1571 sd_read_capacity(sdkp, disk->disk_name, buffer); 1572 sd_read_write_protect_flag(sdkp, disk->disk_name, buffer); 1573 sd_read_cache_type(sdkp, disk->disk_name, buffer); 1574 } 1575 1576 /* 1577 * We now have all cache related info, determine how we deal 1578 * with ordered requests. Note that as the current SCSI 1579 * dispatch function can alter request order, we cannot use 1580 * QUEUE_ORDERED_TAG_* even when ordered tag is supported. 1581 */ 1582 if (sdkp->WCE) 1583 ordered = sdkp->DPOFUA 1584 ? QUEUE_ORDERED_DRAIN_FUA : QUEUE_ORDERED_DRAIN_FLUSH; 1585 else 1586 ordered = QUEUE_ORDERED_DRAIN; 1587 1588 blk_queue_ordered(sdkp->disk->queue, ordered, sd_prepare_flush); 1589 1590 set_capacity(disk, sdkp->capacity); 1591 kfree(buffer); 1592 1593 out: 1594 return 0; 1595 } 1596 1597 /** 1598 * sd_probe - called during driver initialization and whenever a 1599 * new scsi device is attached to the system. It is called once 1600 * for each scsi device (not just disks) present. 1601 * @dev: pointer to device object 1602 * 1603 * Returns 0 if successful (or not interested in this scsi device 1604 * (e.g. scanner)); 1 when there is an error. 1605 * 1606 * Note: this function is invoked from the scsi mid-level. 1607 * This function sets up the mapping between a given 1608 * <host,channel,id,lun> (found in sdp) and new device name 1609 * (e.g. /dev/sda). More precisely it is the block device major 1610 * and minor number that is chosen here. 1611 * 1612 * Assume sd_attach is not re-entrant (for time being) 1613 * Also think about sd_attach() and sd_remove() running coincidentally. 1614 **/ 1615 static int sd_probe(struct device *dev) 1616 { 1617 struct scsi_device *sdp = to_scsi_device(dev); 1618 struct scsi_disk *sdkp; 1619 struct gendisk *gd; 1620 u32 index; 1621 int error; 1622 1623 error = -ENODEV; 1624 if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC) 1625 goto out; 1626 1627 SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp, 1628 "sd_attach\n")); 1629 1630 error = -ENOMEM; 1631 sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL); 1632 if (!sdkp) 1633 goto out; 1634 1635 gd = alloc_disk(16); 1636 if (!gd) 1637 goto out_free; 1638 1639 if (!idr_pre_get(&sd_index_idr, GFP_KERNEL)) 1640 goto out_put; 1641 1642 spin_lock(&sd_index_lock); 1643 error = idr_get_new(&sd_index_idr, NULL, &index); 1644 spin_unlock(&sd_index_lock); 1645 1646 if (index >= SD_MAX_DISKS) 1647 error = -EBUSY; 1648 if (error) 1649 goto out_put; 1650 1651 class_device_initialize(&sdkp->cdev); 1652 sdkp->cdev.dev = &sdp->sdev_gendev; 1653 sdkp->cdev.class = &sd_disk_class; 1654 strncpy(sdkp->cdev.class_id, sdp->sdev_gendev.bus_id, BUS_ID_SIZE); 1655 1656 if (class_device_add(&sdkp->cdev)) 1657 goto out_put; 1658 1659 get_device(&sdp->sdev_gendev); 1660 1661 sdkp->device = sdp; 1662 sdkp->driver = &sd_template; 1663 sdkp->disk = gd; 1664 sdkp->index = index; 1665 sdkp->openers = 0; 1666 1667 if (!sdp->timeout) { 1668 if (sdp->type != TYPE_MOD) 1669 sdp->timeout = SD_TIMEOUT; 1670 else 1671 sdp->timeout = SD_MOD_TIMEOUT; 1672 } 1673 1674 gd->major = sd_major((index & 0xf0) >> 4); 1675 gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00); 1676 gd->minors = 16; 1677 gd->fops = &sd_fops; 1678 1679 if (index < 26) { 1680 sprintf(gd->disk_name, "sd%c", 'a' + index % 26); 1681 } else if (index < (26 + 1) * 26) { 1682 sprintf(gd->disk_name, "sd%c%c", 1683 'a' + index / 26 - 1,'a' + index % 26); 1684 } else { 1685 const unsigned int m1 = (index / 26 - 1) / 26 - 1; 1686 const unsigned int m2 = (index / 26 - 1) % 26; 1687 const unsigned int m3 = index % 26; 1688 sprintf(gd->disk_name, "sd%c%c%c", 1689 'a' + m1, 'a' + m2, 'a' + m3); 1690 } 1691 1692 gd->private_data = &sdkp->driver; 1693 gd->queue = sdkp->device->request_queue; 1694 1695 sd_revalidate_disk(gd); 1696 1697 gd->driverfs_dev = &sdp->sdev_gendev; 1698 gd->flags = GENHD_FL_DRIVERFS; 1699 if (sdp->removable) 1700 gd->flags |= GENHD_FL_REMOVABLE; 1701 1702 dev_set_drvdata(dev, sdkp); 1703 add_disk(gd); 1704 1705 sdev_printk(KERN_NOTICE, sdp, "Attached scsi %sdisk %s\n", 1706 sdp->removable ? "removable " : "", gd->disk_name); 1707 1708 return 0; 1709 1710 out_put: 1711 put_disk(gd); 1712 out_free: 1713 kfree(sdkp); 1714 out: 1715 return error; 1716 } 1717 1718 /** 1719 * sd_remove - called whenever a scsi disk (previously recognized by 1720 * sd_probe) is detached from the system. It is called (potentially 1721 * multiple times) during sd module unload. 1722 * @sdp: pointer to mid level scsi device object 1723 * 1724 * Note: this function is invoked from the scsi mid-level. 1725 * This function potentially frees up a device name (e.g. /dev/sdc) 1726 * that could be re-used by a subsequent sd_probe(). 1727 * This function is not called when the built-in sd driver is "exit-ed". 1728 **/ 1729 static int sd_remove(struct device *dev) 1730 { 1731 struct scsi_disk *sdkp = dev_get_drvdata(dev); 1732 1733 class_device_del(&sdkp->cdev); 1734 del_gendisk(sdkp->disk); 1735 sd_shutdown(dev); 1736 1737 mutex_lock(&sd_ref_mutex); 1738 dev_set_drvdata(dev, NULL); 1739 class_device_put(&sdkp->cdev); 1740 mutex_unlock(&sd_ref_mutex); 1741 1742 return 0; 1743 } 1744 1745 /** 1746 * scsi_disk_release - Called to free the scsi_disk structure 1747 * @cdev: pointer to embedded class device 1748 * 1749 * sd_ref_mutex must be held entering this routine. Because it is 1750 * called on last put, you should always use the scsi_disk_get() 1751 * scsi_disk_put() helpers which manipulate the semaphore directly 1752 * and never do a direct class_device_put(). 1753 **/ 1754 static void scsi_disk_release(struct class_device *cdev) 1755 { 1756 struct scsi_disk *sdkp = to_scsi_disk(cdev); 1757 struct gendisk *disk = sdkp->disk; 1758 1759 spin_lock(&sd_index_lock); 1760 idr_remove(&sd_index_idr, sdkp->index); 1761 spin_unlock(&sd_index_lock); 1762 1763 disk->private_data = NULL; 1764 put_disk(disk); 1765 put_device(&sdkp->device->sdev_gendev); 1766 1767 kfree(sdkp); 1768 } 1769 1770 /* 1771 * Send a SYNCHRONIZE CACHE instruction down to the device through 1772 * the normal SCSI command structure. Wait for the command to 1773 * complete. 1774 */ 1775 static void sd_shutdown(struct device *dev) 1776 { 1777 struct scsi_device *sdp = to_scsi_device(dev); 1778 struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev); 1779 1780 if (!sdkp) 1781 return; /* this can happen */ 1782 1783 if (sdkp->WCE) { 1784 printk(KERN_NOTICE "Synchronizing SCSI cache for disk %s: \n", 1785 sdkp->disk->disk_name); 1786 sd_sync_cache(sdp); 1787 } 1788 scsi_disk_put(sdkp); 1789 } 1790 1791 /** 1792 * init_sd - entry point for this driver (both when built in or when 1793 * a module). 1794 * 1795 * Note: this function registers this driver with the scsi mid-level. 1796 **/ 1797 static int __init init_sd(void) 1798 { 1799 int majors = 0, i; 1800 1801 SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n")); 1802 1803 for (i = 0; i < SD_MAJORS; i++) 1804 if (register_blkdev(sd_major(i), "sd") == 0) 1805 majors++; 1806 1807 if (!majors) 1808 return -ENODEV; 1809 1810 class_register(&sd_disk_class); 1811 1812 return scsi_register_driver(&sd_template.gendrv); 1813 } 1814 1815 /** 1816 * exit_sd - exit point for this driver (when it is a module). 1817 * 1818 * Note: this function unregisters this driver from the scsi mid-level. 1819 **/ 1820 static void __exit exit_sd(void) 1821 { 1822 int i; 1823 1824 SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n")); 1825 1826 scsi_unregister_driver(&sd_template.gendrv); 1827 for (i = 0; i < SD_MAJORS; i++) 1828 unregister_blkdev(sd_major(i), "sd"); 1829 1830 class_unregister(&sd_disk_class); 1831 } 1832 1833 module_init(init_sd); 1834 module_exit(exit_sd); 1835