Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 | /* * gendisk handling */ #include <linux/config.h> #include <linux/module.h> #include <linux/fs.h> #include <linux/genhd.h> #include <linux/kernel.h> #include <linux/blkdev.h> #include <linux/init.h> #include <linux/spinlock.h> #include <linux/seq_file.h> #include <linux/slab.h> #include <linux/kmod.h> #include <linux/kobj_map.h> #include <linux/buffer_head.h> #define MAX_PROBE_HASH 255 /* random */ static struct subsystem block_subsys; static DECLARE_MUTEX(block_subsys_sem); /* * Can be deleted altogether. Later. * */ static struct blk_major_name { struct blk_major_name *next; int major; char name[16]; } *major_names[MAX_PROBE_HASH]; /* index in the above - for now: assume no multimajor ranges */ static inline int major_to_index(int major) { return major % MAX_PROBE_HASH; } #ifdef CONFIG_PROC_FS /* get block device names in somewhat random order */ int get_blkdev_list(char *p, int used) { struct blk_major_name *n; int i, len; len = snprintf(p, (PAGE_SIZE-used), "\nBlock devices:\n"); down(&block_subsys_sem); for (i = 0; i < ARRAY_SIZE(major_names); i++) { for (n = major_names[i]; n; n = n->next) { /* * If the curent string plus the 5 extra characters * in the line would run us off the page, then we're done */ if ((len + used + strlen(n->name) + 5) >= PAGE_SIZE) goto page_full; len += sprintf(p+len, "%3d %s\n", n->major, n->name); } } page_full: up(&block_subsys_sem); return len; } #endif int register_blkdev(unsigned int major, const char *name) { struct blk_major_name **n, *p; int index, ret = 0; down(&block_subsys_sem); /* temporary */ if (major == 0) { for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) { if (major_names[index] == NULL) break; } if (index == 0) { printk("register_blkdev: failed to get major for %s\n", name); ret = -EBUSY; goto out; } major = index; ret = major; } p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL); if (p == NULL) { ret = -ENOMEM; goto out; } p->major = major; strlcpy(p->name, name, sizeof(p->name)); p->next = NULL; index = major_to_index(major); for (n = &major_names[index]; *n; n = &(*n)->next) { if ((*n)->major == major) break; } if (!*n) *n = p; else ret = -EBUSY; if (ret < 0) { printk("register_blkdev: cannot get major %d for %s\n", major, name); kfree(p); } out: up(&block_subsys_sem); return ret; } EXPORT_SYMBOL(register_blkdev); /* todo: make void - error printk here */ int unregister_blkdev(unsigned int major, const char *name) { struct blk_major_name **n; struct blk_major_name *p = NULL; int index = major_to_index(major); int ret = 0; down(&block_subsys_sem); for (n = &major_names[index]; *n; n = &(*n)->next) if ((*n)->major == major) break; if (!*n || strcmp((*n)->name, name)) ret = -EINVAL; else { p = *n; *n = p->next; } up(&block_subsys_sem); kfree(p); return ret; } EXPORT_SYMBOL(unregister_blkdev); static struct kobj_map *bdev_map; /* * Register device numbers dev..(dev+range-1) * range must be nonzero * The hash chain is sorted on range, so that subranges can override. */ void blk_register_region(dev_t dev, unsigned long range, struct module *module, struct kobject *(*probe)(dev_t, int *, void *), int (*lock)(dev_t, void *), void *data) { kobj_map(bdev_map, dev, range, module, probe, lock, data); } EXPORT_SYMBOL(blk_register_region); void blk_unregister_region(dev_t dev, unsigned long range) { kobj_unmap(bdev_map, dev, range); } EXPORT_SYMBOL(blk_unregister_region); static struct kobject *exact_match(dev_t dev, int *part, void *data) { struct gendisk *p = data; return &p->kobj; } static int exact_lock(dev_t dev, void *data) { struct gendisk *p = data; if (!get_disk(p)) return -1; return 0; } /** * add_disk - add partitioning information to kernel list * @disk: per-device partitioning information * * This function registers the partitioning information in @disk * with the kernel. */ void add_disk(struct gendisk *disk) { disk->flags |= GENHD_FL_UP; blk_register_region(MKDEV(disk->major, disk->first_minor), disk->minors, NULL, exact_match, exact_lock, disk); register_disk(disk); blk_register_queue(disk); } EXPORT_SYMBOL(add_disk); EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */ void unlink_gendisk(struct gendisk *disk) { blk_unregister_queue(disk); blk_unregister_region(MKDEV(disk->major, disk->first_minor), disk->minors); } #define to_disk(obj) container_of(obj,struct gendisk,kobj) /** * get_gendisk - get partitioning information for a given device * @dev: device to get partitioning information for * * This function gets the structure containing partitioning * information for the given device @dev. */ struct gendisk *get_gendisk(dev_t dev, int *part) { struct kobject *kobj = kobj_lookup(bdev_map, dev, part); return kobj ? to_disk(kobj) : NULL; } #ifdef CONFIG_PROC_FS /* iterator */ static void *part_start(struct seq_file *part, loff_t *pos) { struct list_head *p; loff_t l = *pos; down(&block_subsys_sem); list_for_each(p, &block_subsys.kset.list) if (!l--) return list_entry(p, struct gendisk, kobj.entry); return NULL; } static void *part_next(struct seq_file *part, void *v, loff_t *pos) { struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; ++*pos; return p==&block_subsys.kset.list ? NULL : list_entry(p, struct gendisk, kobj.entry); } static void part_stop(struct seq_file *part, void *v) { up(&block_subsys_sem); } static int show_partition(struct seq_file *part, void *v) { struct gendisk *sgp = v; int n; char buf[BDEVNAME_SIZE]; if (&sgp->kobj.entry == block_subsys.kset.list.next) seq_puts(part, "major minor #blocks name\n\n"); /* Don't show non-partitionable removeable devices or empty devices */ if (!get_capacity(sgp) || (sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE))) return 0; if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO) return 0; /* show the full disk and all non-0 size partitions of it */ seq_printf(part, "%4d %4d %10llu %s\n", sgp->major, sgp->first_minor, (unsigned long long)get_capacity(sgp) >> 1, disk_name(sgp, 0, buf)); for (n = 0; n < sgp->minors - 1; n++) { if (!sgp->part[n]) continue; if (sgp->part[n]->nr_sects == 0) continue; seq_printf(part, "%4d %4d %10llu %s\n", sgp->major, n + 1 + sgp->first_minor, (unsigned long long)sgp->part[n]->nr_sects >> 1 , disk_name(sgp, n + 1, buf)); } return 0; } struct seq_operations partitions_op = { .start =part_start, .next = part_next, .stop = part_stop, .show = show_partition }; #endif extern int blk_dev_init(void); static struct kobject *base_probe(dev_t dev, int *part, void *data) { if (request_module("block-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0) /* Make old-style 2.4 aliases work */ request_module("block-major-%d", MAJOR(dev)); return NULL; } static int __init genhd_device_init(void) { bdev_map = kobj_map_init(base_probe, &block_subsys_sem); blk_dev_init(); subsystem_register(&block_subsys); return 0; } subsys_initcall(genhd_device_init); /* * kobject & sysfs bindings for block devices */ static ssize_t disk_attr_show(struct kobject *kobj, struct attribute *attr, char *page) { struct gendisk *disk = to_disk(kobj); struct disk_attribute *disk_attr = container_of(attr,struct disk_attribute,attr); ssize_t ret = -EIO; if (disk_attr->show) ret = disk_attr->show(disk,page); return ret; } static struct sysfs_ops disk_sysfs_ops = { .show = &disk_attr_show, }; static ssize_t disk_dev_read(struct gendisk * disk, char *page) { dev_t base = MKDEV(disk->major, disk->first_minor); return print_dev_t(page, base); } static ssize_t disk_range_read(struct gendisk * disk, char *page) { return sprintf(page, "%d\n", disk->minors); } static ssize_t disk_removable_read(struct gendisk * disk, char *page) { return sprintf(page, "%d\n", (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0)); } static ssize_t disk_size_read(struct gendisk * disk, char *page) { return sprintf(page, "%llu\n", (unsigned long long)get_capacity(disk)); } static ssize_t disk_stats_read(struct gendisk * disk, char *page) { preempt_disable(); disk_round_stats(disk); preempt_enable(); return sprintf(page, "%8u %8u %8llu %8u " "%8u %8u %8llu %8u " "%8u %8u %8u" "\n", disk_stat_read(disk, reads), disk_stat_read(disk, read_merges), (unsigned long long)disk_stat_read(disk, read_sectors), jiffies_to_msecs(disk_stat_read(disk, read_ticks)), disk_stat_read(disk, writes), disk_stat_read(disk, write_merges), (unsigned long long)disk_stat_read(disk, write_sectors), jiffies_to_msecs(disk_stat_read(disk, write_ticks)), disk->in_flight, jiffies_to_msecs(disk_stat_read(disk, io_ticks)), jiffies_to_msecs(disk_stat_read(disk, time_in_queue))); } static struct disk_attribute disk_attr_dev = { .attr = {.name = "dev", .mode = S_IRUGO }, .show = disk_dev_read }; static struct disk_attribute disk_attr_range = { .attr = {.name = "range", .mode = S_IRUGO }, .show = disk_range_read }; static struct disk_attribute disk_attr_removable = { .attr = {.name = "removable", .mode = S_IRUGO }, .show = disk_removable_read }; static struct disk_attribute disk_attr_size = { .attr = {.name = "size", .mode = S_IRUGO }, .show = disk_size_read }; static struct disk_attribute disk_attr_stat = { .attr = {.name = "stat", .mode = S_IRUGO }, .show = disk_stats_read }; static struct attribute * default_attrs[] = { &disk_attr_dev.attr, &disk_attr_range.attr, &disk_attr_removable.attr, &disk_attr_size.attr, &disk_attr_stat.attr, NULL, }; static void disk_release(struct kobject * kobj) { struct gendisk *disk = to_disk(kobj); kfree(disk->random); kfree(disk->part); free_disk_stats(disk); kfree(disk); } static struct kobj_type ktype_block = { .release = disk_release, .sysfs_ops = &disk_sysfs_ops, .default_attrs = default_attrs, }; extern struct kobj_type ktype_part; static int block_hotplug_filter(struct kset *kset, struct kobject *kobj) { struct kobj_type *ktype = get_ktype(kobj); return ((ktype == &ktype_block) || (ktype == &ktype_part)); } static int block_hotplug(struct kset *kset, struct kobject *kobj, char **envp, int num_envp, char *buffer, int buffer_size) { struct kobj_type *ktype = get_ktype(kobj); struct device *physdev; struct gendisk *disk; struct hd_struct *part; int length = 0; int i = 0; if (ktype == &ktype_block) { disk = container_of(kobj, struct gendisk, kobj); add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &length, "MINOR=%u", disk->first_minor); } else if (ktype == &ktype_part) { disk = container_of(kobj->parent, struct gendisk, kobj); part = container_of(kobj, struct hd_struct, kobj); add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &length, "MINOR=%u", disk->first_minor + part->partno); } else return 0; add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &length, "MAJOR=%u", disk->major); /* add physical device, backing this device */ physdev = disk->driverfs_dev; if (physdev) { char *path = kobject_get_path(&physdev->kobj, GFP_KERNEL); add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &length, "PHYSDEVPATH=%s", path); kfree(path); if (physdev->bus) add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &length, "PHYSDEVBUS=%s", physdev->bus->name); if (physdev->driver) add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &length, "PHYSDEVDRIVER=%s", physdev->driver->name); } /* terminate, set to next free slot, shrink available space */ envp[i] = NULL; envp = &envp[i]; num_envp -= i; buffer = &buffer[length]; buffer_size -= length; return 0; } static struct kset_hotplug_ops block_hotplug_ops = { .filter = block_hotplug_filter, .hotplug = block_hotplug, }; /* declare block_subsys. */ static decl_subsys(block, &ktype_block, &block_hotplug_ops); /* * aggregate disk stat collector. Uses the same stats that the sysfs * entries do, above, but makes them available through one seq_file. * Watching a few disks may be efficient through sysfs, but watching * all of them will be more efficient through this interface. * * The output looks suspiciously like /proc/partitions with a bunch of * extra fields. */ /* iterator */ static void *diskstats_start(struct seq_file *part, loff_t *pos) { loff_t k = *pos; struct list_head *p; down(&block_subsys_sem); list_for_each(p, &block_subsys.kset.list) if (!k--) return list_entry(p, struct gendisk, kobj.entry); return NULL; } static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos) { struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; ++*pos; return p==&block_subsys.kset.list ? NULL : list_entry(p, struct gendisk, kobj.entry); } static void diskstats_stop(struct seq_file *part, void *v) { up(&block_subsys_sem); } static int diskstats_show(struct seq_file *s, void *v) { struct gendisk *gp = v; char buf[BDEVNAME_SIZE]; int n = 0; /* if (&sgp->kobj.entry == block_subsys.kset.list.next) seq_puts(s, "major minor name" " rio rmerge rsect ruse wio wmerge " "wsect wuse running use aveq" "\n\n"); */ preempt_disable(); disk_round_stats(gp); preempt_enable(); seq_printf(s, "%4d %4d %s %u %u %llu %u %u %u %llu %u %u %u %u\n", gp->major, n + gp->first_minor, disk_name(gp, n, buf), disk_stat_read(gp, reads), disk_stat_read(gp, read_merges), (unsigned long long)disk_stat_read(gp, read_sectors), jiffies_to_msecs(disk_stat_read(gp, read_ticks)), disk_stat_read(gp, writes), disk_stat_read(gp, write_merges), (unsigned long long)disk_stat_read(gp, write_sectors), jiffies_to_msecs(disk_stat_read(gp, write_ticks)), gp->in_flight, jiffies_to_msecs(disk_stat_read(gp, io_ticks)), jiffies_to_msecs(disk_stat_read(gp, time_in_queue))); /* now show all non-0 size partitions of it */ for (n = 0; n < gp->minors - 1; n++) { struct hd_struct *hd = gp->part[n]; if (hd && hd->nr_sects) seq_printf(s, "%4d %4d %s %u %u %u %u\n", gp->major, n + gp->first_minor + 1, disk_name(gp, n + 1, buf), hd->reads, hd->read_sectors, hd->writes, hd->write_sectors); } return 0; } struct seq_operations diskstats_op = { .start = diskstats_start, .next = diskstats_next, .stop = diskstats_stop, .show = diskstats_show }; struct gendisk *alloc_disk(int minors) { return alloc_disk_node(minors, -1); } struct gendisk *alloc_disk_node(int minors, int node_id) { struct gendisk *disk; disk = kmalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id); if (disk) { memset(disk, 0, sizeof(struct gendisk)); if (!init_disk_stats(disk)) { kfree(disk); return NULL; } if (minors > 1) { int size = (minors - 1) * sizeof(struct hd_struct *); disk->part = kmalloc_node(size, GFP_KERNEL, node_id); if (!disk->part) { kfree(disk); return NULL; } memset(disk->part, 0, size); } disk->minors = minors; kobj_set_kset_s(disk,block_subsys); kobject_init(&disk->kobj); rand_initialize_disk(disk); } return disk; } EXPORT_SYMBOL(alloc_disk); EXPORT_SYMBOL(alloc_disk_node); struct kobject *get_disk(struct gendisk *disk) { struct module *owner; struct kobject *kobj; if (!disk->fops) return NULL; owner = disk->fops->owner; if (owner && !try_module_get(owner)) return NULL; kobj = kobject_get(&disk->kobj); if (kobj == NULL) { module_put(owner); return NULL; } return kobj; } EXPORT_SYMBOL(get_disk); void put_disk(struct gendisk *disk) { if (disk) kobject_put(&disk->kobj); } EXPORT_SYMBOL(put_disk); void set_device_ro(struct block_device *bdev, int flag) { if (bdev->bd_contains != bdev) bdev->bd_part->policy = flag; else bdev->bd_disk->policy = flag; } EXPORT_SYMBOL(set_device_ro); void set_disk_ro(struct gendisk *disk, int flag) { int i; disk->policy = flag; for (i = 0; i < disk->minors - 1; i++) if (disk->part[i]) disk->part[i]->policy = flag; } EXPORT_SYMBOL(set_disk_ro); int bdev_read_only(struct block_device *bdev) { if (!bdev) return 0; else if (bdev->bd_contains != bdev) return bdev->bd_part->policy; else return bdev->bd_disk->policy; } EXPORT_SYMBOL(bdev_read_only); int invalidate_partition(struct gendisk *disk, int index) { int res = 0; struct block_device *bdev = bdget_disk(disk, index); if (bdev) { fsync_bdev(bdev); res = __invalidate_device(bdev); bdput(bdev); } return res; } EXPORT_SYMBOL(invalidate_partition); |