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 = this_count * sdp->sector_size; 506 507 /* 508 * We shouldn't disconnect in the middle of a sector, so with a dumb 509 * host adapter, it's safe to assume that we can at least transfer 510 * this many bytes between each connect / disconnect. 511 */ 512 SCpnt->transfersize = sdp->sector_size; 513 SCpnt->underflow = this_count << 9; 514 SCpnt->allowed = SD_MAX_RETRIES; 515 SCpnt->timeout_per_command = timeout; 516 517 /* 518 * This is the completion routine we use. This is matched in terms 519 * of capability to this function. 520 */ 521 SCpnt->done = sd_rw_intr; 522 523 /* 524 * This indicates that the command is ready from our end to be 525 * queued. 526 */ 527 return 1; 528 } 529 530 /** 531 * sd_open - open a scsi disk device 532 * @inode: only i_rdev member may be used 533 * @filp: only f_mode and f_flags may be used 534 * 535 * Returns 0 if successful. Returns a negated errno value in case 536 * of error. 537 * 538 * Note: This can be called from a user context (e.g. fsck(1) ) 539 * or from within the kernel (e.g. as a result of a mount(1) ). 540 * In the latter case @inode and @filp carry an abridged amount 541 * of information as noted above. 542 **/ 543 static int sd_open(struct inode *inode, struct file *filp) 544 { 545 struct gendisk *disk = inode->i_bdev->bd_disk; 546 struct scsi_disk *sdkp; 547 struct scsi_device *sdev; 548 int retval; 549 550 if (!(sdkp = scsi_disk_get(disk))) 551 return -ENXIO; 552 553 554 SCSI_LOG_HLQUEUE(3, printk("sd_open: disk=%s\n", disk->disk_name)); 555 556 sdev = sdkp->device; 557 558 /* 559 * If the device is in error recovery, wait until it is done. 560 * If the device is offline, then disallow any access to it. 561 */ 562 retval = -ENXIO; 563 if (!scsi_block_when_processing_errors(sdev)) 564 goto error_out; 565 566 if (sdev->removable || sdkp->write_prot) 567 check_disk_change(inode->i_bdev); 568 569 /* 570 * If the drive is empty, just let the open fail. 571 */ 572 retval = -ENOMEDIUM; 573 if (sdev->removable && !sdkp->media_present && 574 !(filp->f_flags & O_NDELAY)) 575 goto error_out; 576 577 /* 578 * If the device has the write protect tab set, have the open fail 579 * if the user expects to be able to write to the thing. 580 */ 581 retval = -EROFS; 582 if (sdkp->write_prot && (filp->f_mode & FMODE_WRITE)) 583 goto error_out; 584 585 /* 586 * It is possible that the disk changing stuff resulted in 587 * the device being taken offline. If this is the case, 588 * report this to the user, and don't pretend that the 589 * open actually succeeded. 590 */ 591 retval = -ENXIO; 592 if (!scsi_device_online(sdev)) 593 goto error_out; 594 595 if (!sdkp->openers++ && sdev->removable) { 596 if (scsi_block_when_processing_errors(sdev)) 597 scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT); 598 } 599 600 return 0; 601 602 error_out: 603 scsi_disk_put(sdkp); 604 return retval; 605 } 606 607 /** 608 * sd_release - invoked when the (last) close(2) is called on this 609 * scsi disk. 610 * @inode: only i_rdev member may be used 611 * @filp: only f_mode and f_flags may be used 612 * 613 * Returns 0. 614 * 615 * Note: may block (uninterruptible) if error recovery is underway 616 * on this disk. 617 **/ 618 static int sd_release(struct inode *inode, struct file *filp) 619 { 620 struct gendisk *disk = inode->i_bdev->bd_disk; 621 struct scsi_disk *sdkp = scsi_disk(disk); 622 struct scsi_device *sdev = sdkp->device; 623 624 SCSI_LOG_HLQUEUE(3, printk("sd_release: disk=%s\n", disk->disk_name)); 625 626 if (!--sdkp->openers && sdev->removable) { 627 if (scsi_block_when_processing_errors(sdev)) 628 scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW); 629 } 630 631 /* 632 * XXX and what if there are packets in flight and this close() 633 * XXX is followed by a "rmmod sd_mod"? 634 */ 635 scsi_disk_put(sdkp); 636 return 0; 637 } 638 639 static int sd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 640 { 641 struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk); 642 struct scsi_device *sdp = sdkp->device; 643 struct Scsi_Host *host = sdp->host; 644 int diskinfo[4]; 645 646 /* default to most commonly used values */ 647 diskinfo[0] = 0x40; /* 1 << 6 */ 648 diskinfo[1] = 0x20; /* 1 << 5 */ 649 diskinfo[2] = sdkp->capacity >> 11; 650 651 /* override with calculated, extended default, or driver values */ 652 if (host->hostt->bios_param) 653 host->hostt->bios_param(sdp, bdev, sdkp->capacity, diskinfo); 654 else 655 scsicam_bios_param(bdev, sdkp->capacity, diskinfo); 656 657 geo->heads = diskinfo[0]; 658 geo->sectors = diskinfo[1]; 659 geo->cylinders = diskinfo[2]; 660 return 0; 661 } 662 663 /** 664 * sd_ioctl - process an ioctl 665 * @inode: only i_rdev/i_bdev members may be used 666 * @filp: only f_mode and f_flags may be used 667 * @cmd: ioctl command number 668 * @arg: this is third argument given to ioctl(2) system call. 669 * Often contains a pointer. 670 * 671 * Returns 0 if successful (some ioctls return postive numbers on 672 * success as well). Returns a negated errno value in case of error. 673 * 674 * Note: most ioctls are forward onto the block subsystem or further 675 * down in the scsi subsytem. 676 **/ 677 static int sd_ioctl(struct inode * inode, struct file * filp, 678 unsigned int cmd, unsigned long arg) 679 { 680 struct block_device *bdev = inode->i_bdev; 681 struct gendisk *disk = bdev->bd_disk; 682 struct scsi_device *sdp = scsi_disk(disk)->device; 683 void __user *p = (void __user *)arg; 684 int error; 685 686 SCSI_LOG_IOCTL(1, printk("sd_ioctl: disk=%s, cmd=0x%x\n", 687 disk->disk_name, cmd)); 688 689 /* 690 * If we are in the middle of error recovery, don't let anyone 691 * else try and use this device. Also, if error recovery fails, it 692 * may try and take the device offline, in which case all further 693 * access to the device is prohibited. 694 */ 695 error = scsi_nonblockable_ioctl(sdp, cmd, p, filp); 696 if (!scsi_block_when_processing_errors(sdp) || !error) 697 return error; 698 699 /* 700 * Send SCSI addressing ioctls directly to mid level, send other 701 * ioctls to block level and then onto mid level if they can't be 702 * resolved. 703 */ 704 switch (cmd) { 705 case SCSI_IOCTL_GET_IDLUN: 706 case SCSI_IOCTL_GET_BUS_NUMBER: 707 return scsi_ioctl(sdp, cmd, p); 708 default: 709 error = scsi_cmd_ioctl(filp, disk, cmd, p); 710 if (error != -ENOTTY) 711 return error; 712 } 713 return scsi_ioctl(sdp, cmd, p); 714 } 715 716 static void set_media_not_present(struct scsi_disk *sdkp) 717 { 718 sdkp->media_present = 0; 719 sdkp->capacity = 0; 720 sdkp->device->changed = 1; 721 } 722 723 /** 724 * sd_media_changed - check if our medium changed 725 * @disk: kernel device descriptor 726 * 727 * Returns 0 if not applicable or no change; 1 if change 728 * 729 * Note: this function is invoked from the block subsystem. 730 **/ 731 static int sd_media_changed(struct gendisk *disk) 732 { 733 struct scsi_disk *sdkp = scsi_disk(disk); 734 struct scsi_device *sdp = sdkp->device; 735 int retval; 736 737 SCSI_LOG_HLQUEUE(3, printk("sd_media_changed: disk=%s\n", 738 disk->disk_name)); 739 740 if (!sdp->removable) 741 return 0; 742 743 /* 744 * If the device is offline, don't send any commands - just pretend as 745 * if the command failed. If the device ever comes back online, we 746 * can deal with it then. It is only because of unrecoverable errors 747 * that we would ever take a device offline in the first place. 748 */ 749 if (!scsi_device_online(sdp)) 750 goto not_present; 751 752 /* 753 * Using TEST_UNIT_READY enables differentiation between drive with 754 * no cartridge loaded - NOT READY, drive with changed cartridge - 755 * UNIT ATTENTION, or with same cartridge - GOOD STATUS. 756 * 757 * Drives that auto spin down. eg iomega jaz 1G, will be started 758 * by sd_spinup_disk() from sd_revalidate_disk(), which happens whenever 759 * sd_revalidate() is called. 760 */ 761 retval = -ENODEV; 762 if (scsi_block_when_processing_errors(sdp)) 763 retval = scsi_test_unit_ready(sdp, SD_TIMEOUT, SD_MAX_RETRIES); 764 765 /* 766 * Unable to test, unit probably not ready. This usually 767 * means there is no disc in the drive. Mark as changed, 768 * and we will figure it out later once the drive is 769 * available again. 770 */ 771 if (retval) 772 goto not_present; 773 774 /* 775 * For removable scsi disk we have to recognise the presence 776 * of a disk in the drive. This is kept in the struct scsi_disk 777 * struct and tested at open ! Daniel Roche (dan@lectra.fr) 778 */ 779 sdkp->media_present = 1; 780 781 retval = sdp->changed; 782 sdp->changed = 0; 783 784 return retval; 785 786 not_present: 787 set_media_not_present(sdkp); 788 return 1; 789 } 790 791 static int sd_sync_cache(struct scsi_device *sdp) 792 { 793 int retries, res; 794 struct scsi_sense_hdr sshdr; 795 796 if (!scsi_device_online(sdp)) 797 return -ENODEV; 798 799 800 for (retries = 3; retries > 0; --retries) { 801 unsigned char cmd[10] = { 0 }; 802 803 cmd[0] = SYNCHRONIZE_CACHE; 804 /* 805 * Leave the rest of the command zero to indicate 806 * flush everything. 807 */ 808 res = scsi_execute_req(sdp, cmd, DMA_NONE, NULL, 0, &sshdr, 809 SD_TIMEOUT, SD_MAX_RETRIES); 810 if (res == 0) 811 break; 812 } 813 814 if (res) { printk(KERN_WARNING "FAILED\n status = %x, message = %02x, " 815 "host = %d, driver = %02x\n ", 816 status_byte(res), msg_byte(res), 817 host_byte(res), driver_byte(res)); 818 if (driver_byte(res) & DRIVER_SENSE) 819 scsi_print_sense_hdr("sd", &sshdr); 820 } 821 822 return res; 823 } 824 825 static int sd_issue_flush(struct device *dev, sector_t *error_sector) 826 { 827 int ret = 0; 828 struct scsi_device *sdp = to_scsi_device(dev); 829 struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev); 830 831 if (!sdkp) 832 return -ENODEV; 833 834 if (sdkp->WCE) 835 ret = sd_sync_cache(sdp); 836 scsi_disk_put(sdkp); 837 return ret; 838 } 839 840 static void sd_prepare_flush(request_queue_t *q, struct request *rq) 841 { 842 memset(rq->cmd, 0, sizeof(rq->cmd)); 843 rq->flags |= REQ_BLOCK_PC; 844 rq->timeout = SD_TIMEOUT; 845 rq->cmd[0] = SYNCHRONIZE_CACHE; 846 rq->cmd_len = 10; 847 } 848 849 static void sd_rescan(struct device *dev) 850 { 851 struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev); 852 853 if (sdkp) { 854 sd_revalidate_disk(sdkp->disk); 855 scsi_disk_put(sdkp); 856 } 857 } 858 859 860 #ifdef CONFIG_COMPAT 861 /* 862 * This gets directly called from VFS. When the ioctl 863 * is not recognized we go back to the other translation paths. 864 */ 865 static long sd_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 866 { 867 struct block_device *bdev = file->f_dentry->d_inode->i_bdev; 868 struct gendisk *disk = bdev->bd_disk; 869 struct scsi_device *sdev = scsi_disk(disk)->device; 870 871 /* 872 * If we are in the middle of error recovery, don't let anyone 873 * else try and use this device. Also, if error recovery fails, it 874 * may try and take the device offline, in which case all further 875 * access to the device is prohibited. 876 */ 877 if (!scsi_block_when_processing_errors(sdev)) 878 return -ENODEV; 879 880 if (sdev->host->hostt->compat_ioctl) { 881 int ret; 882 883 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg); 884 885 return ret; 886 } 887 888 /* 889 * Let the static ioctl translation table take care of it. 890 */ 891 return -ENOIOCTLCMD; 892 } 893 #endif 894 895 static struct block_device_operations sd_fops = { 896 .owner = THIS_MODULE, 897 .open = sd_open, 898 .release = sd_release, 899 .ioctl = sd_ioctl, 900 .getgeo = sd_getgeo, 901 #ifdef CONFIG_COMPAT 902 .compat_ioctl = sd_compat_ioctl, 903 #endif 904 .media_changed = sd_media_changed, 905 .revalidate_disk = sd_revalidate_disk, 906 }; 907 908 /** 909 * sd_rw_intr - bottom half handler: called when the lower level 910 * driver has completed (successfully or otherwise) a scsi command. 911 * @SCpnt: mid-level's per command structure. 912 * 913 * Note: potentially run from within an ISR. Must not block. 914 **/ 915 static void sd_rw_intr(struct scsi_cmnd * SCpnt) 916 { 917 int result = SCpnt->result; 918 unsigned int xfer_size = SCpnt->request_bufflen; 919 unsigned int good_bytes = result ? 0 : xfer_size; 920 u64 start_lba = SCpnt->request->sector; 921 u64 bad_lba; 922 struct scsi_sense_hdr sshdr; 923 int sense_valid = 0; 924 int sense_deferred = 0; 925 int info_valid; 926 927 if (result) { 928 sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr); 929 if (sense_valid) 930 sense_deferred = scsi_sense_is_deferred(&sshdr); 931 } 932 #ifdef CONFIG_SCSI_LOGGING 933 SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: %s: res=0x%x\n", 934 SCpnt->request->rq_disk->disk_name, result)); 935 if (sense_valid) { 936 SCSI_LOG_HLCOMPLETE(1, printk("sd_rw_intr: sb[respc,sk,asc," 937 "ascq]=%x,%x,%x,%x\n", sshdr.response_code, 938 sshdr.sense_key, sshdr.asc, sshdr.ascq)); 939 } 940 #endif 941 if (driver_byte(result) != DRIVER_SENSE && 942 (!sense_valid || sense_deferred)) 943 goto out; 944 945 switch (sshdr.sense_key) { 946 case HARDWARE_ERROR: 947 case MEDIUM_ERROR: 948 if (!blk_fs_request(SCpnt->request)) 949 goto out; 950 info_valid = scsi_get_sense_info_fld(SCpnt->sense_buffer, 951 SCSI_SENSE_BUFFERSIZE, 952 &bad_lba); 953 if (!info_valid) 954 goto out; 955 if (xfer_size <= SCpnt->device->sector_size) 956 goto out; 957 switch (SCpnt->device->sector_size) { 958 case 256: 959 start_lba <<= 1; 960 break; 961 case 512: 962 break; 963 case 1024: 964 start_lba >>= 1; 965 break; 966 case 2048: 967 start_lba >>= 2; 968 break; 969 case 4096: 970 start_lba >>= 3; 971 break; 972 default: 973 /* Print something here with limiting frequency. */ 974 goto out; 975 break; 976 } 977 /* This computation should always be done in terms of 978 * the resolution of the device's medium. 979 */ 980 good_bytes = (bad_lba - start_lba)*SCpnt->device->sector_size; 981 break; 982 case RECOVERED_ERROR: 983 case NO_SENSE: 984 /* Inform the user, but make sure that it's not treated 985 * as a hard error. 986 */ 987 scsi_print_sense("sd", SCpnt); 988 SCpnt->result = 0; 989 memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE); 990 good_bytes = xfer_size; 991 break; 992 case ILLEGAL_REQUEST: 993 if (SCpnt->device->use_10_for_rw && 994 (SCpnt->cmnd[0] == READ_10 || 995 SCpnt->cmnd[0] == WRITE_10)) 996 SCpnt->device->use_10_for_rw = 0; 997 if (SCpnt->device->use_10_for_ms && 998 (SCpnt->cmnd[0] == MODE_SENSE_10 || 999 SCpnt->cmnd[0] == MODE_SELECT_10)) 1000 SCpnt->device->use_10_for_ms = 0; 1001 break; 1002 default: 1003 break; 1004 } 1005 out: 1006 scsi_io_completion(SCpnt, good_bytes); 1007 } 1008 1009 static int media_not_present(struct scsi_disk *sdkp, 1010 struct scsi_sense_hdr *sshdr) 1011 { 1012 1013 if (!scsi_sense_valid(sshdr)) 1014 return 0; 1015 /* not invoked for commands that could return deferred errors */ 1016 if (sshdr->sense_key != NOT_READY && 1017 sshdr->sense_key != UNIT_ATTENTION) 1018 return 0; 1019 if (sshdr->asc != 0x3A) /* medium not present */ 1020 return 0; 1021 1022 set_media_not_present(sdkp); 1023 return 1; 1024 } 1025 1026 /* 1027 * spinup disk - called only in sd_revalidate_disk() 1028 */ 1029 static void 1030 sd_spinup_disk(struct scsi_disk *sdkp, char *diskname) 1031 { 1032 unsigned char cmd[10]; 1033 unsigned long spintime_expire = 0; 1034 int retries, spintime; 1035 unsigned int the_result; 1036 struct scsi_sense_hdr sshdr; 1037 int sense_valid = 0; 1038 1039 spintime = 0; 1040 1041 /* Spin up drives, as required. Only do this at boot time */ 1042 /* Spinup needs to be done for module loads too. */ 1043 do { 1044 retries = 0; 1045 1046 do { 1047 cmd[0] = TEST_UNIT_READY; 1048 memset((void *) &cmd[1], 0, 9); 1049 1050 the_result = scsi_execute_req(sdkp->device, cmd, 1051 DMA_NONE, NULL, 0, 1052 &sshdr, SD_TIMEOUT, 1053 SD_MAX_RETRIES); 1054 1055 if (the_result) 1056 sense_valid = scsi_sense_valid(&sshdr); 1057 retries++; 1058 } while (retries < 3 && 1059 (!scsi_status_is_good(the_result) || 1060 ((driver_byte(the_result) & DRIVER_SENSE) && 1061 sense_valid && sshdr.sense_key == UNIT_ATTENTION))); 1062 1063 /* 1064 * If the drive has indicated to us that it doesn't have 1065 * any media in it, don't bother with any of the rest of 1066 * this crap. 1067 */ 1068 if (media_not_present(sdkp, &sshdr)) 1069 return; 1070 1071 if ((driver_byte(the_result) & DRIVER_SENSE) == 0) { 1072 /* no sense, TUR either succeeded or failed 1073 * with a status error */ 1074 if(!spintime && !scsi_status_is_good(the_result)) 1075 printk(KERN_NOTICE "%s: Unit Not Ready, " 1076 "error = 0x%x\n", diskname, the_result); 1077 break; 1078 } 1079 1080 /* 1081 * The device does not want the automatic start to be issued. 1082 */ 1083 if (sdkp->device->no_start_on_add) { 1084 break; 1085 } 1086 1087 /* 1088 * If manual intervention is required, or this is an 1089 * absent USB storage device, a spinup is meaningless. 1090 */ 1091 if (sense_valid && 1092 sshdr.sense_key == NOT_READY && 1093 sshdr.asc == 4 && sshdr.ascq == 3) { 1094 break; /* manual intervention required */ 1095 1096 /* 1097 * Issue command to spin up drive when not ready 1098 */ 1099 } else if (sense_valid && sshdr.sense_key == NOT_READY) { 1100 if (!spintime) { 1101 printk(KERN_NOTICE "%s: Spinning up disk...", 1102 diskname); 1103 cmd[0] = START_STOP; 1104 cmd[1] = 1; /* Return immediately */ 1105 memset((void *) &cmd[2], 0, 8); 1106 cmd[4] = 1; /* Start spin cycle */ 1107 scsi_execute_req(sdkp->device, cmd, DMA_NONE, 1108 NULL, 0, &sshdr, 1109 SD_TIMEOUT, SD_MAX_RETRIES); 1110 spintime_expire = jiffies + 100 * HZ; 1111 spintime = 1; 1112 } 1113 /* Wait 1 second for next try */ 1114 msleep(1000); 1115 printk("."); 1116 1117 /* 1118 * Wait for USB flash devices with slow firmware. 1119 * Yes, this sense key/ASC combination shouldn't 1120 * occur here. It's characteristic of these devices. 1121 */ 1122 } else if (sense_valid && 1123 sshdr.sense_key == UNIT_ATTENTION && 1124 sshdr.asc == 0x28) { 1125 if (!spintime) { 1126 spintime_expire = jiffies + 5 * HZ; 1127 spintime = 1; 1128 } 1129 /* Wait 1 second for next try */ 1130 msleep(1000); 1131 } else { 1132 /* we don't understand the sense code, so it's 1133 * probably pointless to loop */ 1134 if(!spintime) { 1135 printk(KERN_NOTICE "%s: Unit Not Ready, " 1136 "sense:\n", diskname); 1137 scsi_print_sense_hdr("", &sshdr); 1138 } 1139 break; 1140 } 1141 1142 } while (spintime && time_before_eq(jiffies, spintime_expire)); 1143 1144 if (spintime) { 1145 if (scsi_status_is_good(the_result)) 1146 printk("ready\n"); 1147 else 1148 printk("not responding...\n"); 1149 } 1150 } 1151 1152 /* 1153 * read disk capacity 1154 */ 1155 static void 1156 sd_read_capacity(struct scsi_disk *sdkp, char *diskname, 1157 unsigned char *buffer) 1158 { 1159 unsigned char cmd[16]; 1160 int the_result, retries; 1161 int sector_size = 0; 1162 int longrc = 0; 1163 struct scsi_sense_hdr sshdr; 1164 int sense_valid = 0; 1165 struct scsi_device *sdp = sdkp->device; 1166 1167 repeat: 1168 retries = 3; 1169 do { 1170 if (longrc) { 1171 memset((void *) cmd, 0, 16); 1172 cmd[0] = SERVICE_ACTION_IN; 1173 cmd[1] = SAI_READ_CAPACITY_16; 1174 cmd[13] = 12; 1175 memset((void *) buffer, 0, 12); 1176 } else { 1177 cmd[0] = READ_CAPACITY; 1178 memset((void *) &cmd[1], 0, 9); 1179 memset((void *) buffer, 0, 8); 1180 } 1181 1182 the_result = scsi_execute_req(sdp, cmd, DMA_FROM_DEVICE, 1183 buffer, longrc ? 12 : 8, &sshdr, 1184 SD_TIMEOUT, SD_MAX_RETRIES); 1185 1186 if (media_not_present(sdkp, &sshdr)) 1187 return; 1188 1189 if (the_result) 1190 sense_valid = scsi_sense_valid(&sshdr); 1191 retries--; 1192 1193 } while (the_result && retries); 1194 1195 if (the_result && !longrc) { 1196 printk(KERN_NOTICE "%s : READ CAPACITY failed.\n" 1197 "%s : status=%x, message=%02x, host=%d, driver=%02x \n", 1198 diskname, diskname, 1199 status_byte(the_result), 1200 msg_byte(the_result), 1201 host_byte(the_result), 1202 driver_byte(the_result)); 1203 1204 if (driver_byte(the_result) & DRIVER_SENSE) 1205 scsi_print_sense_hdr("sd", &sshdr); 1206 else 1207 printk("%s : sense not available. \n", diskname); 1208 1209 /* Set dirty bit for removable devices if not ready - 1210 * sometimes drives will not report this properly. */ 1211 if (sdp->removable && 1212 sense_valid && sshdr.sense_key == NOT_READY) 1213 sdp->changed = 1; 1214 1215 /* Either no media are present but the drive didn't tell us, 1216 or they are present but the read capacity command fails */ 1217 /* sdkp->media_present = 0; -- not always correct */ 1218 sdkp->capacity = 0x200000; /* 1 GB - random */ 1219 1220 return; 1221 } else if (the_result && longrc) { 1222 /* READ CAPACITY(16) has been failed */ 1223 printk(KERN_NOTICE "%s : READ CAPACITY(16) failed.\n" 1224 "%s : status=%x, message=%02x, host=%d, driver=%02x \n", 1225 diskname, diskname, 1226 status_byte(the_result), 1227 msg_byte(the_result), 1228 host_byte(the_result), 1229 driver_byte(the_result)); 1230 printk(KERN_NOTICE "%s : use 0xffffffff as device size\n", 1231 diskname); 1232 1233 sdkp->capacity = 1 + (sector_t) 0xffffffff; 1234 goto got_data; 1235 } 1236 1237 if (!longrc) { 1238 sector_size = (buffer[4] << 24) | 1239 (buffer[5] << 16) | (buffer[6] << 8) | buffer[7]; 1240 if (buffer[0] == 0xff && buffer[1] == 0xff && 1241 buffer[2] == 0xff && buffer[3] == 0xff) { 1242 if(sizeof(sdkp->capacity) > 4) { 1243 printk(KERN_NOTICE "%s : very big device. try to use" 1244 " READ CAPACITY(16).\n", diskname); 1245 longrc = 1; 1246 goto repeat; 1247 } 1248 printk(KERN_ERR "%s: too big for this kernel. Use a " 1249 "kernel compiled with support for large block " 1250 "devices.\n", diskname); 1251 sdkp->capacity = 0; 1252 goto got_data; 1253 } 1254 sdkp->capacity = 1 + (((sector_t)buffer[0] << 24) | 1255 (buffer[1] << 16) | 1256 (buffer[2] << 8) | 1257 buffer[3]); 1258 } else { 1259 sdkp->capacity = 1 + (((u64)buffer[0] << 56) | 1260 ((u64)buffer[1] << 48) | 1261 ((u64)buffer[2] << 40) | 1262 ((u64)buffer[3] << 32) | 1263 ((sector_t)buffer[4] << 24) | 1264 ((sector_t)buffer[5] << 16) | 1265 ((sector_t)buffer[6] << 8) | 1266 (sector_t)buffer[7]); 1267 1268 sector_size = (buffer[8] << 24) | 1269 (buffer[9] << 16) | (buffer[10] << 8) | buffer[11]; 1270 } 1271 1272 /* Some devices return the total number of sectors, not the 1273 * highest sector number. Make the necessary adjustment. */ 1274 if (sdp->fix_capacity) 1275 --sdkp->capacity; 1276 1277 got_data: 1278 if (sector_size == 0) { 1279 sector_size = 512; 1280 printk(KERN_NOTICE "%s : sector size 0 reported, " 1281 "assuming 512.\n", diskname); 1282 } 1283 1284 if (sector_size != 512 && 1285 sector_size != 1024 && 1286 sector_size != 2048 && 1287 sector_size != 4096 && 1288 sector_size != 256) { 1289 printk(KERN_NOTICE "%s : unsupported sector size " 1290 "%d.\n", diskname, sector_size); 1291 /* 1292 * The user might want to re-format the drive with 1293 * a supported sectorsize. Once this happens, it 1294 * would be relatively trivial to set the thing up. 1295 * For this reason, we leave the thing in the table. 1296 */ 1297 sdkp->capacity = 0; 1298 /* 1299 * set a bogus sector size so the normal read/write 1300 * logic in the block layer will eventually refuse any 1301 * request on this device without tripping over power 1302 * of two sector size assumptions 1303 */ 1304 sector_size = 512; 1305 } 1306 { 1307 /* 1308 * The msdos fs needs to know the hardware sector size 1309 * So I have created this table. See ll_rw_blk.c 1310 * Jacques Gelinas (Jacques@solucorp.qc.ca) 1311 */ 1312 int hard_sector = sector_size; 1313 sector_t sz = (sdkp->capacity/2) * (hard_sector/256); 1314 request_queue_t *queue = sdp->request_queue; 1315 sector_t mb = sz; 1316 1317 blk_queue_hardsect_size(queue, hard_sector); 1318 /* avoid 64-bit division on 32-bit platforms */ 1319 sector_div(sz, 625); 1320 mb -= sz - 974; 1321 sector_div(mb, 1950); 1322 1323 printk(KERN_NOTICE "SCSI device %s: " 1324 "%llu %d-byte hdwr sectors (%llu MB)\n", 1325 diskname, (unsigned long long)sdkp->capacity, 1326 hard_sector, (unsigned long long)mb); 1327 } 1328 1329 /* Rescale capacity to 512-byte units */ 1330 if (sector_size == 4096) 1331 sdkp->capacity <<= 3; 1332 else if (sector_size == 2048) 1333 sdkp->capacity <<= 2; 1334 else if (sector_size == 1024) 1335 sdkp->capacity <<= 1; 1336 else if (sector_size == 256) 1337 sdkp->capacity >>= 1; 1338 1339 sdkp->device->sector_size = sector_size; 1340 } 1341 1342 /* called with buffer of length 512 */ 1343 static inline int 1344 sd_do_mode_sense(struct scsi_device *sdp, int dbd, int modepage, 1345 unsigned char *buffer, int len, struct scsi_mode_data *data, 1346 struct scsi_sense_hdr *sshdr) 1347 { 1348 return scsi_mode_sense(sdp, dbd, modepage, buffer, len, 1349 SD_TIMEOUT, SD_MAX_RETRIES, data, 1350 sshdr); 1351 } 1352 1353 /* 1354 * read write protect setting, if possible - called only in sd_revalidate_disk() 1355 * called with buffer of length SD_BUF_SIZE 1356 */ 1357 static void 1358 sd_read_write_protect_flag(struct scsi_disk *sdkp, char *diskname, 1359 unsigned char *buffer) 1360 { 1361 int res; 1362 struct scsi_device *sdp = sdkp->device; 1363 struct scsi_mode_data data; 1364 1365 set_disk_ro(sdkp->disk, 0); 1366 if (sdp->skip_ms_page_3f) { 1367 printk(KERN_NOTICE "%s: assuming Write Enabled\n", diskname); 1368 return; 1369 } 1370 1371 if (sdp->use_192_bytes_for_3f) { 1372 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 192, &data, NULL); 1373 } else { 1374 /* 1375 * First attempt: ask for all pages (0x3F), but only 4 bytes. 1376 * We have to start carefully: some devices hang if we ask 1377 * for more than is available. 1378 */ 1379 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 4, &data, NULL); 1380 1381 /* 1382 * Second attempt: ask for page 0 When only page 0 is 1383 * implemented, a request for page 3F may return Sense Key 1384 * 5: Illegal Request, Sense Code 24: Invalid field in 1385 * CDB. 1386 */ 1387 if (!scsi_status_is_good(res)) 1388 res = sd_do_mode_sense(sdp, 0, 0, buffer, 4, &data, NULL); 1389 1390 /* 1391 * Third attempt: ask 255 bytes, as we did earlier. 1392 */ 1393 if (!scsi_status_is_good(res)) 1394 res = sd_do_mode_sense(sdp, 0, 0x3F, buffer, 255, 1395 &data, NULL); 1396 } 1397 1398 if (!scsi_status_is_good(res)) { 1399 printk(KERN_WARNING 1400 "%s: test WP failed, assume Write Enabled\n", diskname); 1401 } else { 1402 sdkp->write_prot = ((data.device_specific & 0x80) != 0); 1403 set_disk_ro(sdkp->disk, sdkp->write_prot); 1404 printk(KERN_NOTICE "%s: Write Protect is %s\n", diskname, 1405 sdkp->write_prot ? "on" : "off"); 1406 printk(KERN_DEBUG "%s: Mode Sense: %02x %02x %02x %02x\n", 1407 diskname, buffer[0], buffer[1], buffer[2], buffer[3]); 1408 } 1409 } 1410 1411 /* 1412 * sd_read_cache_type - called only from sd_revalidate_disk() 1413 * called with buffer of length SD_BUF_SIZE 1414 */ 1415 static void 1416 sd_read_cache_type(struct scsi_disk *sdkp, char *diskname, 1417 unsigned char *buffer) 1418 { 1419 int len = 0, res; 1420 struct scsi_device *sdp = sdkp->device; 1421 1422 int dbd; 1423 int modepage; 1424 struct scsi_mode_data data; 1425 struct scsi_sense_hdr sshdr; 1426 1427 if (sdp->skip_ms_page_8) 1428 goto defaults; 1429 1430 if (sdp->type == TYPE_RBC) { 1431 modepage = 6; 1432 dbd = 8; 1433 } else { 1434 modepage = 8; 1435 dbd = 0; 1436 } 1437 1438 /* cautiously ask */ 1439 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, 4, &data, &sshdr); 1440 1441 if (!scsi_status_is_good(res)) 1442 goto bad_sense; 1443 1444 if (!data.header_length) { 1445 modepage = 6; 1446 printk(KERN_ERR "%s: missing header in MODE_SENSE response\n", 1447 diskname); 1448 } 1449 1450 /* that went OK, now ask for the proper length */ 1451 len = data.length; 1452 1453 /* 1454 * We're only interested in the first three bytes, actually. 1455 * But the data cache page is defined for the first 20. 1456 */ 1457 if (len < 3) 1458 goto bad_sense; 1459 if (len > 20) 1460 len = 20; 1461 1462 /* Take headers and block descriptors into account */ 1463 len += data.header_length + data.block_descriptor_length; 1464 if (len > SD_BUF_SIZE) 1465 goto bad_sense; 1466 1467 /* Get the data */ 1468 res = sd_do_mode_sense(sdp, dbd, modepage, buffer, len, &data, &sshdr); 1469 1470 if (scsi_status_is_good(res)) { 1471 int ct = 0; 1472 int offset = data.header_length + data.block_descriptor_length; 1473 1474 if (offset >= SD_BUF_SIZE - 2) { 1475 printk(KERN_ERR "%s: malformed MODE SENSE response", 1476 diskname); 1477 goto defaults; 1478 } 1479 1480 if ((buffer[offset] & 0x3f) != modepage) { 1481 printk(KERN_ERR "%s: got wrong page\n", diskname); 1482 goto defaults; 1483 } 1484 1485 if (modepage == 8) { 1486 sdkp->WCE = ((buffer[offset + 2] & 0x04) != 0); 1487 sdkp->RCD = ((buffer[offset + 2] & 0x01) != 0); 1488 } else { 1489 sdkp->WCE = ((buffer[offset + 2] & 0x01) == 0); 1490 sdkp->RCD = 0; 1491 } 1492 1493 sdkp->DPOFUA = (data.device_specific & 0x10) != 0; 1494 if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) { 1495 printk(KERN_NOTICE "SCSI device %s: uses " 1496 "READ/WRITE(6), disabling FUA\n", diskname); 1497 sdkp->DPOFUA = 0; 1498 } 1499 1500 ct = sdkp->RCD + 2*sdkp->WCE; 1501 1502 printk(KERN_NOTICE "SCSI device %s: drive cache: %s%s\n", 1503 diskname, sd_cache_types[ct], 1504 sdkp->DPOFUA ? " w/ FUA" : ""); 1505 1506 return; 1507 } 1508 1509 bad_sense: 1510 if (scsi_sense_valid(&sshdr) && 1511 sshdr.sense_key == ILLEGAL_REQUEST && 1512 sshdr.asc == 0x24 && sshdr.ascq == 0x0) 1513 printk(KERN_NOTICE "%s: cache data unavailable\n", 1514 diskname); /* Invalid field in CDB */ 1515 else 1516 printk(KERN_ERR "%s: asking for cache data failed\n", 1517 diskname); 1518 1519 defaults: 1520 printk(KERN_ERR "%s: assuming drive cache: write through\n", 1521 diskname); 1522 sdkp->WCE = 0; 1523 sdkp->RCD = 0; 1524 sdkp->DPOFUA = 0; 1525 } 1526 1527 /** 1528 * sd_revalidate_disk - called the first time a new disk is seen, 1529 * performs disk spin up, read_capacity, etc. 1530 * @disk: struct gendisk we care about 1531 **/ 1532 static int sd_revalidate_disk(struct gendisk *disk) 1533 { 1534 struct scsi_disk *sdkp = scsi_disk(disk); 1535 struct scsi_device *sdp = sdkp->device; 1536 unsigned char *buffer; 1537 unsigned ordered; 1538 1539 SCSI_LOG_HLQUEUE(3, printk("sd_revalidate_disk: disk=%s\n", disk->disk_name)); 1540 1541 /* 1542 * If the device is offline, don't try and read capacity or any 1543 * of the other niceties. 1544 */ 1545 if (!scsi_device_online(sdp)) 1546 goto out; 1547 1548 buffer = kmalloc(SD_BUF_SIZE, GFP_KERNEL | __GFP_DMA); 1549 if (!buffer) { 1550 printk(KERN_WARNING "(sd_revalidate_disk:) Memory allocation " 1551 "failure.\n"); 1552 goto out; 1553 } 1554 1555 /* defaults, until the device tells us otherwise */ 1556 sdp->sector_size = 512; 1557 sdkp->capacity = 0; 1558 sdkp->media_present = 1; 1559 sdkp->write_prot = 0; 1560 sdkp->WCE = 0; 1561 sdkp->RCD = 0; 1562 1563 sd_spinup_disk(sdkp, disk->disk_name); 1564 1565 /* 1566 * Without media there is no reason to ask; moreover, some devices 1567 * react badly if we do. 1568 */ 1569 if (sdkp->media_present) { 1570 sd_read_capacity(sdkp, disk->disk_name, buffer); 1571 sd_read_write_protect_flag(sdkp, disk->disk_name, buffer); 1572 sd_read_cache_type(sdkp, disk->disk_name, buffer); 1573 } 1574 1575 /* 1576 * We now have all cache related info, determine how we deal 1577 * with ordered requests. Note that as the current SCSI 1578 * dispatch function can alter request order, we cannot use 1579 * QUEUE_ORDERED_TAG_* even when ordered tag is supported. 1580 */ 1581 if (sdkp->WCE) 1582 ordered = sdkp->DPOFUA 1583 ? QUEUE_ORDERED_DRAIN_FUA : QUEUE_ORDERED_DRAIN_FLUSH; 1584 else 1585 ordered = QUEUE_ORDERED_DRAIN; 1586 1587 blk_queue_ordered(sdkp->disk->queue, ordered, sd_prepare_flush); 1588 1589 set_capacity(disk, sdkp->capacity); 1590 kfree(buffer); 1591 1592 out: 1593 return 0; 1594 } 1595 1596 /** 1597 * sd_probe - called during driver initialization and whenever a 1598 * new scsi device is attached to the system. It is called once 1599 * for each scsi device (not just disks) present. 1600 * @dev: pointer to device object 1601 * 1602 * Returns 0 if successful (or not interested in this scsi device 1603 * (e.g. scanner)); 1 when there is an error. 1604 * 1605 * Note: this function is invoked from the scsi mid-level. 1606 * This function sets up the mapping between a given 1607 * <host,channel,id,lun> (found in sdp) and new device name 1608 * (e.g. /dev/sda). More precisely it is the block device major 1609 * and minor number that is chosen here. 1610 * 1611 * Assume sd_attach is not re-entrant (for time being) 1612 * Also think about sd_attach() and sd_remove() running coincidentally. 1613 **/ 1614 static int sd_probe(struct device *dev) 1615 { 1616 struct scsi_device *sdp = to_scsi_device(dev); 1617 struct scsi_disk *sdkp; 1618 struct gendisk *gd; 1619 u32 index; 1620 int error; 1621 1622 error = -ENODEV; 1623 if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC) 1624 goto out; 1625 1626 SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp, 1627 "sd_attach\n")); 1628 1629 error = -ENOMEM; 1630 sdkp = kzalloc(sizeof(*sdkp), GFP_KERNEL); 1631 if (!sdkp) 1632 goto out; 1633 1634 gd = alloc_disk(16); 1635 if (!gd) 1636 goto out_free; 1637 1638 if (!idr_pre_get(&sd_index_idr, GFP_KERNEL)) 1639 goto out_put; 1640 1641 spin_lock(&sd_index_lock); 1642 error = idr_get_new(&sd_index_idr, NULL, &index); 1643 spin_unlock(&sd_index_lock); 1644 1645 if (index >= SD_MAX_DISKS) 1646 error = -EBUSY; 1647 if (error) 1648 goto out_put; 1649 1650 class_device_initialize(&sdkp->cdev); 1651 sdkp->cdev.dev = &sdp->sdev_gendev; 1652 sdkp->cdev.class = &sd_disk_class; 1653 strncpy(sdkp->cdev.class_id, sdp->sdev_gendev.bus_id, BUS_ID_SIZE); 1654 1655 if (class_device_add(&sdkp->cdev)) 1656 goto out_put; 1657 1658 get_device(&sdp->sdev_gendev); 1659 1660 sdkp->device = sdp; 1661 sdkp->driver = &sd_template; 1662 sdkp->disk = gd; 1663 sdkp->index = index; 1664 sdkp->openers = 0; 1665 1666 if (!sdp->timeout) { 1667 if (sdp->type != TYPE_MOD) 1668 sdp->timeout = SD_TIMEOUT; 1669 else 1670 sdp->timeout = SD_MOD_TIMEOUT; 1671 } 1672 1673 gd->major = sd_major((index & 0xf0) >> 4); 1674 gd->first_minor = ((index & 0xf) << 4) | (index & 0xfff00); 1675 gd->minors = 16; 1676 gd->fops = &sd_fops; 1677 1678 if (index < 26) { 1679 sprintf(gd->disk_name, "sd%c", 'a' + index % 26); 1680 } else if (index < (26 + 1) * 26) { 1681 sprintf(gd->disk_name, "sd%c%c", 1682 'a' + index / 26 - 1,'a' + index % 26); 1683 } else { 1684 const unsigned int m1 = (index / 26 - 1) / 26 - 1; 1685 const unsigned int m2 = (index / 26 - 1) % 26; 1686 const unsigned int m3 = index % 26; 1687 sprintf(gd->disk_name, "sd%c%c%c", 1688 'a' + m1, 'a' + m2, 'a' + m3); 1689 } 1690 1691 gd->private_data = &sdkp->driver; 1692 gd->queue = sdkp->device->request_queue; 1693 1694 sd_revalidate_disk(gd); 1695 1696 gd->driverfs_dev = &sdp->sdev_gendev; 1697 gd->flags = GENHD_FL_DRIVERFS; 1698 if (sdp->removable) 1699 gd->flags |= GENHD_FL_REMOVABLE; 1700 1701 dev_set_drvdata(dev, sdkp); 1702 add_disk(gd); 1703 1704 sdev_printk(KERN_NOTICE, sdp, "Attached scsi %sdisk %s\n", 1705 sdp->removable ? "removable " : "", gd->disk_name); 1706 1707 return 0; 1708 1709 out_put: 1710 put_disk(gd); 1711 out_free: 1712 kfree(sdkp); 1713 out: 1714 return error; 1715 } 1716 1717 /** 1718 * sd_remove - called whenever a scsi disk (previously recognized by 1719 * sd_probe) is detached from the system. It is called (potentially 1720 * multiple times) during sd module unload. 1721 * @sdp: pointer to mid level scsi device object 1722 * 1723 * Note: this function is invoked from the scsi mid-level. 1724 * This function potentially frees up a device name (e.g. /dev/sdc) 1725 * that could be re-used by a subsequent sd_probe(). 1726 * This function is not called when the built-in sd driver is "exit-ed". 1727 **/ 1728 static int sd_remove(struct device *dev) 1729 { 1730 struct scsi_disk *sdkp = dev_get_drvdata(dev); 1731 1732 class_device_del(&sdkp->cdev); 1733 del_gendisk(sdkp->disk); 1734 sd_shutdown(dev); 1735 1736 mutex_lock(&sd_ref_mutex); 1737 dev_set_drvdata(dev, NULL); 1738 class_device_put(&sdkp->cdev); 1739 mutex_unlock(&sd_ref_mutex); 1740 1741 return 0; 1742 } 1743 1744 /** 1745 * scsi_disk_release - Called to free the scsi_disk structure 1746 * @cdev: pointer to embedded class device 1747 * 1748 * sd_ref_mutex must be held entering this routine. Because it is 1749 * called on last put, you should always use the scsi_disk_get() 1750 * scsi_disk_put() helpers which manipulate the semaphore directly 1751 * and never do a direct class_device_put(). 1752 **/ 1753 static void scsi_disk_release(struct class_device *cdev) 1754 { 1755 struct scsi_disk *sdkp = to_scsi_disk(cdev); 1756 struct gendisk *disk = sdkp->disk; 1757 1758 spin_lock(&sd_index_lock); 1759 idr_remove(&sd_index_idr, sdkp->index); 1760 spin_unlock(&sd_index_lock); 1761 1762 disk->private_data = NULL; 1763 put_disk(disk); 1764 put_device(&sdkp->device->sdev_gendev); 1765 1766 kfree(sdkp); 1767 } 1768 1769 /* 1770 * Send a SYNCHRONIZE CACHE instruction down to the device through 1771 * the normal SCSI command structure. Wait for the command to 1772 * complete. 1773 */ 1774 static void sd_shutdown(struct device *dev) 1775 { 1776 struct scsi_device *sdp = to_scsi_device(dev); 1777 struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev); 1778 1779 if (!sdkp) 1780 return; /* this can happen */ 1781 1782 if (sdkp->WCE) { 1783 printk(KERN_NOTICE "Synchronizing SCSI cache for disk %s: \n", 1784 sdkp->disk->disk_name); 1785 sd_sync_cache(sdp); 1786 } 1787 scsi_disk_put(sdkp); 1788 } 1789 1790 /** 1791 * init_sd - entry point for this driver (both when built in or when 1792 * a module). 1793 * 1794 * Note: this function registers this driver with the scsi mid-level. 1795 **/ 1796 static int __init init_sd(void) 1797 { 1798 int majors = 0, i; 1799 1800 SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n")); 1801 1802 for (i = 0; i < SD_MAJORS; i++) 1803 if (register_blkdev(sd_major(i), "sd") == 0) 1804 majors++; 1805 1806 if (!majors) 1807 return -ENODEV; 1808 1809 class_register(&sd_disk_class); 1810 1811 return scsi_register_driver(&sd_template.gendrv); 1812 } 1813 1814 /** 1815 * exit_sd - exit point for this driver (when it is a module). 1816 * 1817 * Note: this function unregisters this driver from the scsi mid-level. 1818 **/ 1819 static void __exit exit_sd(void) 1820 { 1821 int i; 1822 1823 SCSI_LOG_HLQUEUE(3, printk("exit_sd: exiting sd driver\n")); 1824 1825 scsi_unregister_driver(&sd_template.gendrv); 1826 for (i = 0; i < SD_MAJORS; i++) 1827 unregister_blkdev(sd_major(i), "sd"); 1828 1829 class_unregister(&sd_disk_class); 1830 } 1831 1832 module_init(init_sd); 1833 module_exit(exit_sd); 1834