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1 | /* | |
2 | * gendisk handling | |
3 | */ | |
4 | ||
5 | #include <linux/module.h> | |
6 | #include <linux/fs.h> | |
7 | #include <linux/genhd.h> | |
8 | #include <linux/kdev_t.h> | |
9 | #include <linux/kernel.h> | |
10 | #include <linux/blkdev.h> | |
11 | #include <linux/init.h> | |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/proc_fs.h> | |
14 | #include <linux/seq_file.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/kmod.h> | |
17 | #include <linux/kobj_map.h> | |
18 | #include <linux/buffer_head.h> | |
19 | #include <linux/mutex.h> | |
20 | #include <linux/idr.h> | |
21 | ||
22 | #include "blk.h" | |
23 | ||
24 | static DEFINE_MUTEX(block_class_lock); | |
25 | #ifndef CONFIG_SYSFS_DEPRECATED | |
26 | struct kobject *block_depr; | |
27 | #endif | |
28 | ||
29 | /* for extended dynamic devt allocation, currently only one major is used */ | |
30 | #define MAX_EXT_DEVT (1 << MINORBITS) | |
31 | ||
32 | /* For extended devt allocation. ext_devt_mutex prevents look up | |
33 | * results from going away underneath its user. | |
34 | */ | |
35 | static DEFINE_MUTEX(ext_devt_mutex); | |
36 | static DEFINE_IDR(ext_devt_idr); | |
37 | ||
38 | static struct device_type disk_type; | |
39 | ||
40 | /** | |
41 | * disk_get_part - get partition | |
42 | * @disk: disk to look partition from | |
43 | * @partno: partition number | |
44 | * | |
45 | * Look for partition @partno from @disk. If found, increment | |
46 | * reference count and return it. | |
47 | * | |
48 | * CONTEXT: | |
49 | * Don't care. | |
50 | * | |
51 | * RETURNS: | |
52 | * Pointer to the found partition on success, NULL if not found. | |
53 | */ | |
54 | struct hd_struct *disk_get_part(struct gendisk *disk, int partno) | |
55 | { | |
56 | struct hd_struct *part = NULL; | |
57 | struct disk_part_tbl *ptbl; | |
58 | ||
59 | if (unlikely(partno < 0)) | |
60 | return NULL; | |
61 | ||
62 | rcu_read_lock(); | |
63 | ||
64 | ptbl = rcu_dereference(disk->part_tbl); | |
65 | if (likely(partno < ptbl->len)) { | |
66 | part = rcu_dereference(ptbl->part[partno]); | |
67 | if (part) | |
68 | get_device(part_to_dev(part)); | |
69 | } | |
70 | ||
71 | rcu_read_unlock(); | |
72 | ||
73 | return part; | |
74 | } | |
75 | EXPORT_SYMBOL_GPL(disk_get_part); | |
76 | ||
77 | /** | |
78 | * disk_part_iter_init - initialize partition iterator | |
79 | * @piter: iterator to initialize | |
80 | * @disk: disk to iterate over | |
81 | * @flags: DISK_PITER_* flags | |
82 | * | |
83 | * Initialize @piter so that it iterates over partitions of @disk. | |
84 | * | |
85 | * CONTEXT: | |
86 | * Don't care. | |
87 | */ | |
88 | void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk, | |
89 | unsigned int flags) | |
90 | { | |
91 | struct disk_part_tbl *ptbl; | |
92 | ||
93 | rcu_read_lock(); | |
94 | ptbl = rcu_dereference(disk->part_tbl); | |
95 | ||
96 | piter->disk = disk; | |
97 | piter->part = NULL; | |
98 | ||
99 | if (flags & DISK_PITER_REVERSE) | |
100 | piter->idx = ptbl->len - 1; | |
101 | else if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0)) | |
102 | piter->idx = 0; | |
103 | else | |
104 | piter->idx = 1; | |
105 | ||
106 | piter->flags = flags; | |
107 | ||
108 | rcu_read_unlock(); | |
109 | } | |
110 | EXPORT_SYMBOL_GPL(disk_part_iter_init); | |
111 | ||
112 | /** | |
113 | * disk_part_iter_next - proceed iterator to the next partition and return it | |
114 | * @piter: iterator of interest | |
115 | * | |
116 | * Proceed @piter to the next partition and return it. | |
117 | * | |
118 | * CONTEXT: | |
119 | * Don't care. | |
120 | */ | |
121 | struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter) | |
122 | { | |
123 | struct disk_part_tbl *ptbl; | |
124 | int inc, end; | |
125 | ||
126 | /* put the last partition */ | |
127 | disk_put_part(piter->part); | |
128 | piter->part = NULL; | |
129 | ||
130 | /* get part_tbl */ | |
131 | rcu_read_lock(); | |
132 | ptbl = rcu_dereference(piter->disk->part_tbl); | |
133 | ||
134 | /* determine iteration parameters */ | |
135 | if (piter->flags & DISK_PITER_REVERSE) { | |
136 | inc = -1; | |
137 | if (piter->flags & (DISK_PITER_INCL_PART0 | | |
138 | DISK_PITER_INCL_EMPTY_PART0)) | |
139 | end = -1; | |
140 | else | |
141 | end = 0; | |
142 | } else { | |
143 | inc = 1; | |
144 | end = ptbl->len; | |
145 | } | |
146 | ||
147 | /* iterate to the next partition */ | |
148 | for (; piter->idx != end; piter->idx += inc) { | |
149 | struct hd_struct *part; | |
150 | ||
151 | part = rcu_dereference(ptbl->part[piter->idx]); | |
152 | if (!part) | |
153 | continue; | |
154 | if (!part->nr_sects && | |
155 | !(piter->flags & DISK_PITER_INCL_EMPTY) && | |
156 | !(piter->flags & DISK_PITER_INCL_EMPTY_PART0 && | |
157 | piter->idx == 0)) | |
158 | continue; | |
159 | ||
160 | get_device(part_to_dev(part)); | |
161 | piter->part = part; | |
162 | piter->idx += inc; | |
163 | break; | |
164 | } | |
165 | ||
166 | rcu_read_unlock(); | |
167 | ||
168 | return piter->part; | |
169 | } | |
170 | EXPORT_SYMBOL_GPL(disk_part_iter_next); | |
171 | ||
172 | /** | |
173 | * disk_part_iter_exit - finish up partition iteration | |
174 | * @piter: iter of interest | |
175 | * | |
176 | * Called when iteration is over. Cleans up @piter. | |
177 | * | |
178 | * CONTEXT: | |
179 | * Don't care. | |
180 | */ | |
181 | void disk_part_iter_exit(struct disk_part_iter *piter) | |
182 | { | |
183 | disk_put_part(piter->part); | |
184 | piter->part = NULL; | |
185 | } | |
186 | EXPORT_SYMBOL_GPL(disk_part_iter_exit); | |
187 | ||
188 | static inline int sector_in_part(struct hd_struct *part, sector_t sector) | |
189 | { | |
190 | return part->start_sect <= sector && | |
191 | sector < part->start_sect + part->nr_sects; | |
192 | } | |
193 | ||
194 | /** | |
195 | * disk_map_sector_rcu - map sector to partition | |
196 | * @disk: gendisk of interest | |
197 | * @sector: sector to map | |
198 | * | |
199 | * Find out which partition @sector maps to on @disk. This is | |
200 | * primarily used for stats accounting. | |
201 | * | |
202 | * CONTEXT: | |
203 | * RCU read locked. The returned partition pointer is valid only | |
204 | * while preemption is disabled. | |
205 | * | |
206 | * RETURNS: | |
207 | * Found partition on success, part0 is returned if no partition matches | |
208 | */ | |
209 | struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) | |
210 | { | |
211 | struct disk_part_tbl *ptbl; | |
212 | struct hd_struct *part; | |
213 | int i; | |
214 | ||
215 | ptbl = rcu_dereference(disk->part_tbl); | |
216 | ||
217 | part = rcu_dereference(ptbl->last_lookup); | |
218 | if (part && sector_in_part(part, sector)) | |
219 | return part; | |
220 | ||
221 | for (i = 1; i < ptbl->len; i++) { | |
222 | part = rcu_dereference(ptbl->part[i]); | |
223 | ||
224 | if (part && sector_in_part(part, sector)) { | |
225 | rcu_assign_pointer(ptbl->last_lookup, part); | |
226 | return part; | |
227 | } | |
228 | } | |
229 | return &disk->part0; | |
230 | } | |
231 | EXPORT_SYMBOL_GPL(disk_map_sector_rcu); | |
232 | ||
233 | /* | |
234 | * Can be deleted altogether. Later. | |
235 | * | |
236 | */ | |
237 | static struct blk_major_name { | |
238 | struct blk_major_name *next; | |
239 | int major; | |
240 | char name[16]; | |
241 | } *major_names[BLKDEV_MAJOR_HASH_SIZE]; | |
242 | ||
243 | /* index in the above - for now: assume no multimajor ranges */ | |
244 | static inline int major_to_index(int major) | |
245 | { | |
246 | return major % BLKDEV_MAJOR_HASH_SIZE; | |
247 | } | |
248 | ||
249 | #ifdef CONFIG_PROC_FS | |
250 | void blkdev_show(struct seq_file *seqf, off_t offset) | |
251 | { | |
252 | struct blk_major_name *dp; | |
253 | ||
254 | if (offset < BLKDEV_MAJOR_HASH_SIZE) { | |
255 | mutex_lock(&block_class_lock); | |
256 | for (dp = major_names[offset]; dp; dp = dp->next) | |
257 | seq_printf(seqf, "%3d %s\n", dp->major, dp->name); | |
258 | mutex_unlock(&block_class_lock); | |
259 | } | |
260 | } | |
261 | #endif /* CONFIG_PROC_FS */ | |
262 | ||
263 | /** | |
264 | * register_blkdev - register a new block device | |
265 | * | |
266 | * @major: the requested major device number [1..255]. If @major=0, try to | |
267 | * allocate any unused major number. | |
268 | * @name: the name of the new block device as a zero terminated string | |
269 | * | |
270 | * The @name must be unique within the system. | |
271 | * | |
272 | * The return value depends on the @major input parameter. | |
273 | * - if a major device number was requested in range [1..255] then the | |
274 | * function returns zero on success, or a negative error code | |
275 | * - if any unused major number was requested with @major=0 parameter | |
276 | * then the return value is the allocated major number in range | |
277 | * [1..255] or a negative error code otherwise | |
278 | */ | |
279 | int register_blkdev(unsigned int major, const char *name) | |
280 | { | |
281 | struct blk_major_name **n, *p; | |
282 | int index, ret = 0; | |
283 | ||
284 | mutex_lock(&block_class_lock); | |
285 | ||
286 | /* temporary */ | |
287 | if (major == 0) { | |
288 | for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) { | |
289 | if (major_names[index] == NULL) | |
290 | break; | |
291 | } | |
292 | ||
293 | if (index == 0) { | |
294 | printk("register_blkdev: failed to get major for %s\n", | |
295 | name); | |
296 | ret = -EBUSY; | |
297 | goto out; | |
298 | } | |
299 | major = index; | |
300 | ret = major; | |
301 | } | |
302 | ||
303 | p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL); | |
304 | if (p == NULL) { | |
305 | ret = -ENOMEM; | |
306 | goto out; | |
307 | } | |
308 | ||
309 | p->major = major; | |
310 | strlcpy(p->name, name, sizeof(p->name)); | |
311 | p->next = NULL; | |
312 | index = major_to_index(major); | |
313 | ||
314 | for (n = &major_names[index]; *n; n = &(*n)->next) { | |
315 | if ((*n)->major == major) | |
316 | break; | |
317 | } | |
318 | if (!*n) | |
319 | *n = p; | |
320 | else | |
321 | ret = -EBUSY; | |
322 | ||
323 | if (ret < 0) { | |
324 | printk("register_blkdev: cannot get major %d for %s\n", | |
325 | major, name); | |
326 | kfree(p); | |
327 | } | |
328 | out: | |
329 | mutex_unlock(&block_class_lock); | |
330 | return ret; | |
331 | } | |
332 | ||
333 | EXPORT_SYMBOL(register_blkdev); | |
334 | ||
335 | void unregister_blkdev(unsigned int major, const char *name) | |
336 | { | |
337 | struct blk_major_name **n; | |
338 | struct blk_major_name *p = NULL; | |
339 | int index = major_to_index(major); | |
340 | ||
341 | mutex_lock(&block_class_lock); | |
342 | for (n = &major_names[index]; *n; n = &(*n)->next) | |
343 | if ((*n)->major == major) | |
344 | break; | |
345 | if (!*n || strcmp((*n)->name, name)) { | |
346 | WARN_ON(1); | |
347 | } else { | |
348 | p = *n; | |
349 | *n = p->next; | |
350 | } | |
351 | mutex_unlock(&block_class_lock); | |
352 | kfree(p); | |
353 | } | |
354 | ||
355 | EXPORT_SYMBOL(unregister_blkdev); | |
356 | ||
357 | static struct kobj_map *bdev_map; | |
358 | ||
359 | /** | |
360 | * blk_mangle_minor - scatter minor numbers apart | |
361 | * @minor: minor number to mangle | |
362 | * | |
363 | * Scatter consecutively allocated @minor number apart if MANGLE_DEVT | |
364 | * is enabled. Mangling twice gives the original value. | |
365 | * | |
366 | * RETURNS: | |
367 | * Mangled value. | |
368 | * | |
369 | * CONTEXT: | |
370 | * Don't care. | |
371 | */ | |
372 | static int blk_mangle_minor(int minor) | |
373 | { | |
374 | #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT | |
375 | int i; | |
376 | ||
377 | for (i = 0; i < MINORBITS / 2; i++) { | |
378 | int low = minor & (1 << i); | |
379 | int high = minor & (1 << (MINORBITS - 1 - i)); | |
380 | int distance = MINORBITS - 1 - 2 * i; | |
381 | ||
382 | minor ^= low | high; /* clear both bits */ | |
383 | low <<= distance; /* swap the positions */ | |
384 | high >>= distance; | |
385 | minor |= low | high; /* and set */ | |
386 | } | |
387 | #endif | |
388 | return minor; | |
389 | } | |
390 | ||
391 | /** | |
392 | * blk_alloc_devt - allocate a dev_t for a partition | |
393 | * @part: partition to allocate dev_t for | |
394 | * @devt: out parameter for resulting dev_t | |
395 | * | |
396 | * Allocate a dev_t for block device. | |
397 | * | |
398 | * RETURNS: | |
399 | * 0 on success, allocated dev_t is returned in *@devt. -errno on | |
400 | * failure. | |
401 | * | |
402 | * CONTEXT: | |
403 | * Might sleep. | |
404 | */ | |
405 | int blk_alloc_devt(struct hd_struct *part, dev_t *devt) | |
406 | { | |
407 | struct gendisk *disk = part_to_disk(part); | |
408 | int idx, rc; | |
409 | ||
410 | /* in consecutive minor range? */ | |
411 | if (part->partno < disk->minors) { | |
412 | *devt = MKDEV(disk->major, disk->first_minor + part->partno); | |
413 | return 0; | |
414 | } | |
415 | ||
416 | /* allocate ext devt */ | |
417 | do { | |
418 | if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL)) | |
419 | return -ENOMEM; | |
420 | rc = idr_get_new(&ext_devt_idr, part, &idx); | |
421 | } while (rc == -EAGAIN); | |
422 | ||
423 | if (rc) | |
424 | return rc; | |
425 | ||
426 | if (idx > MAX_EXT_DEVT) { | |
427 | idr_remove(&ext_devt_idr, idx); | |
428 | return -EBUSY; | |
429 | } | |
430 | ||
431 | *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx)); | |
432 | return 0; | |
433 | } | |
434 | ||
435 | /** | |
436 | * blk_free_devt - free a dev_t | |
437 | * @devt: dev_t to free | |
438 | * | |
439 | * Free @devt which was allocated using blk_alloc_devt(). | |
440 | * | |
441 | * CONTEXT: | |
442 | * Might sleep. | |
443 | */ | |
444 | void blk_free_devt(dev_t devt) | |
445 | { | |
446 | might_sleep(); | |
447 | ||
448 | if (devt == MKDEV(0, 0)) | |
449 | return; | |
450 | ||
451 | if (MAJOR(devt) == BLOCK_EXT_MAJOR) { | |
452 | mutex_lock(&ext_devt_mutex); | |
453 | idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt))); | |
454 | mutex_unlock(&ext_devt_mutex); | |
455 | } | |
456 | } | |
457 | ||
458 | static char *bdevt_str(dev_t devt, char *buf) | |
459 | { | |
460 | if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) { | |
461 | char tbuf[BDEVT_SIZE]; | |
462 | snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt)); | |
463 | snprintf(buf, BDEVT_SIZE, "%-9s", tbuf); | |
464 | } else | |
465 | snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt)); | |
466 | ||
467 | return buf; | |
468 | } | |
469 | ||
470 | /* | |
471 | * Register device numbers dev..(dev+range-1) | |
472 | * range must be nonzero | |
473 | * The hash chain is sorted on range, so that subranges can override. | |
474 | */ | |
475 | void blk_register_region(dev_t devt, unsigned long range, struct module *module, | |
476 | struct kobject *(*probe)(dev_t, int *, void *), | |
477 | int (*lock)(dev_t, void *), void *data) | |
478 | { | |
479 | kobj_map(bdev_map, devt, range, module, probe, lock, data); | |
480 | } | |
481 | ||
482 | EXPORT_SYMBOL(blk_register_region); | |
483 | ||
484 | void blk_unregister_region(dev_t devt, unsigned long range) | |
485 | { | |
486 | kobj_unmap(bdev_map, devt, range); | |
487 | } | |
488 | ||
489 | EXPORT_SYMBOL(blk_unregister_region); | |
490 | ||
491 | static struct kobject *exact_match(dev_t devt, int *partno, void *data) | |
492 | { | |
493 | struct gendisk *p = data; | |
494 | ||
495 | return &disk_to_dev(p)->kobj; | |
496 | } | |
497 | ||
498 | static int exact_lock(dev_t devt, void *data) | |
499 | { | |
500 | struct gendisk *p = data; | |
501 | ||
502 | if (!get_disk(p)) | |
503 | return -1; | |
504 | return 0; | |
505 | } | |
506 | ||
507 | /** | |
508 | * add_disk - add partitioning information to kernel list | |
509 | * @disk: per-device partitioning information | |
510 | * | |
511 | * This function registers the partitioning information in @disk | |
512 | * with the kernel. | |
513 | * | |
514 | * FIXME: error handling | |
515 | */ | |
516 | void add_disk(struct gendisk *disk) | |
517 | { | |
518 | struct backing_dev_info *bdi; | |
519 | dev_t devt; | |
520 | int retval; | |
521 | ||
522 | /* minors == 0 indicates to use ext devt from part0 and should | |
523 | * be accompanied with EXT_DEVT flag. Make sure all | |
524 | * parameters make sense. | |
525 | */ | |
526 | WARN_ON(disk->minors && !(disk->major || disk->first_minor)); | |
527 | WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT)); | |
528 | ||
529 | disk->flags |= GENHD_FL_UP; | |
530 | ||
531 | retval = blk_alloc_devt(&disk->part0, &devt); | |
532 | if (retval) { | |
533 | WARN_ON(1); | |
534 | return; | |
535 | } | |
536 | disk_to_dev(disk)->devt = devt; | |
537 | ||
538 | /* ->major and ->first_minor aren't supposed to be | |
539 | * dereferenced from here on, but set them just in case. | |
540 | */ | |
541 | disk->major = MAJOR(devt); | |
542 | disk->first_minor = MINOR(devt); | |
543 | ||
544 | blk_register_region(disk_devt(disk), disk->minors, NULL, | |
545 | exact_match, exact_lock, disk); | |
546 | register_disk(disk); | |
547 | blk_register_queue(disk); | |
548 | ||
549 | bdi = &disk->queue->backing_dev_info; | |
550 | bdi_register_dev(bdi, disk_devt(disk)); | |
551 | retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj, | |
552 | "bdi"); | |
553 | WARN_ON(retval); | |
554 | } | |
555 | ||
556 | EXPORT_SYMBOL(add_disk); | |
557 | EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */ | |
558 | ||
559 | void unlink_gendisk(struct gendisk *disk) | |
560 | { | |
561 | sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi"); | |
562 | bdi_unregister(&disk->queue->backing_dev_info); | |
563 | blk_unregister_queue(disk); | |
564 | blk_unregister_region(disk_devt(disk), disk->minors); | |
565 | } | |
566 | ||
567 | /** | |
568 | * get_gendisk - get partitioning information for a given device | |
569 | * @devt: device to get partitioning information for | |
570 | * @partno: returned partition index | |
571 | * | |
572 | * This function gets the structure containing partitioning | |
573 | * information for the given device @devt. | |
574 | */ | |
575 | struct gendisk *get_gendisk(dev_t devt, int *partno) | |
576 | { | |
577 | struct gendisk *disk = NULL; | |
578 | ||
579 | if (MAJOR(devt) != BLOCK_EXT_MAJOR) { | |
580 | struct kobject *kobj; | |
581 | ||
582 | kobj = kobj_lookup(bdev_map, devt, partno); | |
583 | if (kobj) | |
584 | disk = dev_to_disk(kobj_to_dev(kobj)); | |
585 | } else { | |
586 | struct hd_struct *part; | |
587 | ||
588 | mutex_lock(&ext_devt_mutex); | |
589 | part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt))); | |
590 | if (part && get_disk(part_to_disk(part))) { | |
591 | *partno = part->partno; | |
592 | disk = part_to_disk(part); | |
593 | } | |
594 | mutex_unlock(&ext_devt_mutex); | |
595 | } | |
596 | ||
597 | return disk; | |
598 | } | |
599 | EXPORT_SYMBOL(get_gendisk); | |
600 | ||
601 | /** | |
602 | * bdget_disk - do bdget() by gendisk and partition number | |
603 | * @disk: gendisk of interest | |
604 | * @partno: partition number | |
605 | * | |
606 | * Find partition @partno from @disk, do bdget() on it. | |
607 | * | |
608 | * CONTEXT: | |
609 | * Don't care. | |
610 | * | |
611 | * RETURNS: | |
612 | * Resulting block_device on success, NULL on failure. | |
613 | */ | |
614 | struct block_device *bdget_disk(struct gendisk *disk, int partno) | |
615 | { | |
616 | struct hd_struct *part; | |
617 | struct block_device *bdev = NULL; | |
618 | ||
619 | part = disk_get_part(disk, partno); | |
620 | if (part) | |
621 | bdev = bdget(part_devt(part)); | |
622 | disk_put_part(part); | |
623 | ||
624 | return bdev; | |
625 | } | |
626 | EXPORT_SYMBOL(bdget_disk); | |
627 | ||
628 | /* | |
629 | * print a full list of all partitions - intended for places where the root | |
630 | * filesystem can't be mounted and thus to give the victim some idea of what | |
631 | * went wrong | |
632 | */ | |
633 | void __init printk_all_partitions(void) | |
634 | { | |
635 | struct class_dev_iter iter; | |
636 | struct device *dev; | |
637 | ||
638 | class_dev_iter_init(&iter, &block_class, NULL, &disk_type); | |
639 | while ((dev = class_dev_iter_next(&iter))) { | |
640 | struct gendisk *disk = dev_to_disk(dev); | |
641 | struct disk_part_iter piter; | |
642 | struct hd_struct *part; | |
643 | char name_buf[BDEVNAME_SIZE]; | |
644 | char devt_buf[BDEVT_SIZE]; | |
645 | ||
646 | /* | |
647 | * Don't show empty devices or things that have been | |
648 | * surpressed | |
649 | */ | |
650 | if (get_capacity(disk) == 0 || | |
651 | (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)) | |
652 | continue; | |
653 | ||
654 | /* | |
655 | * Note, unlike /proc/partitions, I am showing the | |
656 | * numbers in hex - the same format as the root= | |
657 | * option takes. | |
658 | */ | |
659 | disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); | |
660 | while ((part = disk_part_iter_next(&piter))) { | |
661 | bool is_part0 = part == &disk->part0; | |
662 | ||
663 | printk("%s%s %10llu %s", is_part0 ? "" : " ", | |
664 | bdevt_str(part_devt(part), devt_buf), | |
665 | (unsigned long long)part->nr_sects >> 1, | |
666 | disk_name(disk, part->partno, name_buf)); | |
667 | if (is_part0) { | |
668 | if (disk->driverfs_dev != NULL && | |
669 | disk->driverfs_dev->driver != NULL) | |
670 | printk(" driver: %s\n", | |
671 | disk->driverfs_dev->driver->name); | |
672 | else | |
673 | printk(" (driver?)\n"); | |
674 | } else | |
675 | printk("\n"); | |
676 | } | |
677 | disk_part_iter_exit(&piter); | |
678 | } | |
679 | class_dev_iter_exit(&iter); | |
680 | } | |
681 | ||
682 | #ifdef CONFIG_PROC_FS | |
683 | /* iterator */ | |
684 | static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos) | |
685 | { | |
686 | loff_t skip = *pos; | |
687 | struct class_dev_iter *iter; | |
688 | struct device *dev; | |
689 | ||
690 | iter = kmalloc(sizeof(*iter), GFP_KERNEL); | |
691 | if (!iter) | |
692 | return ERR_PTR(-ENOMEM); | |
693 | ||
694 | seqf->private = iter; | |
695 | class_dev_iter_init(iter, &block_class, NULL, &disk_type); | |
696 | do { | |
697 | dev = class_dev_iter_next(iter); | |
698 | if (!dev) | |
699 | return NULL; | |
700 | } while (skip--); | |
701 | ||
702 | return dev_to_disk(dev); | |
703 | } | |
704 | ||
705 | static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos) | |
706 | { | |
707 | struct device *dev; | |
708 | ||
709 | (*pos)++; | |
710 | dev = class_dev_iter_next(seqf->private); | |
711 | if (dev) | |
712 | return dev_to_disk(dev); | |
713 | ||
714 | return NULL; | |
715 | } | |
716 | ||
717 | static void disk_seqf_stop(struct seq_file *seqf, void *v) | |
718 | { | |
719 | struct class_dev_iter *iter = seqf->private; | |
720 | ||
721 | /* stop is called even after start failed :-( */ | |
722 | if (iter) { | |
723 | class_dev_iter_exit(iter); | |
724 | kfree(iter); | |
725 | } | |
726 | } | |
727 | ||
728 | static void *show_partition_start(struct seq_file *seqf, loff_t *pos) | |
729 | { | |
730 | static void *p; | |
731 | ||
732 | p = disk_seqf_start(seqf, pos); | |
733 | if (!IS_ERR(p) && p && !*pos) | |
734 | seq_puts(seqf, "major minor #blocks name\n\n"); | |
735 | return p; | |
736 | } | |
737 | ||
738 | static int show_partition(struct seq_file *seqf, void *v) | |
739 | { | |
740 | struct gendisk *sgp = v; | |
741 | struct disk_part_iter piter; | |
742 | struct hd_struct *part; | |
743 | char buf[BDEVNAME_SIZE]; | |
744 | ||
745 | /* Don't show non-partitionable removeable devices or empty devices */ | |
746 | if (!get_capacity(sgp) || (!disk_partitionable(sgp) && | |
747 | (sgp->flags & GENHD_FL_REMOVABLE))) | |
748 | return 0; | |
749 | if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO) | |
750 | return 0; | |
751 | ||
752 | /* show the full disk and all non-0 size partitions of it */ | |
753 | disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0); | |
754 | while ((part = disk_part_iter_next(&piter))) | |
755 | seq_printf(seqf, "%4d %7d %10llu %s\n", | |
756 | MAJOR(part_devt(part)), MINOR(part_devt(part)), | |
757 | (unsigned long long)part->nr_sects >> 1, | |
758 | disk_name(sgp, part->partno, buf)); | |
759 | disk_part_iter_exit(&piter); | |
760 | ||
761 | return 0; | |
762 | } | |
763 | ||
764 | static const struct seq_operations partitions_op = { | |
765 | .start = show_partition_start, | |
766 | .next = disk_seqf_next, | |
767 | .stop = disk_seqf_stop, | |
768 | .show = show_partition | |
769 | }; | |
770 | ||
771 | static int partitions_open(struct inode *inode, struct file *file) | |
772 | { | |
773 | return seq_open(file, &partitions_op); | |
774 | } | |
775 | ||
776 | static const struct file_operations proc_partitions_operations = { | |
777 | .open = partitions_open, | |
778 | .read = seq_read, | |
779 | .llseek = seq_lseek, | |
780 | .release = seq_release, | |
781 | }; | |
782 | #endif | |
783 | ||
784 | ||
785 | static struct kobject *base_probe(dev_t devt, int *partno, void *data) | |
786 | { | |
787 | if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0) | |
788 | /* Make old-style 2.4 aliases work */ | |
789 | request_module("block-major-%d", MAJOR(devt)); | |
790 | return NULL; | |
791 | } | |
792 | ||
793 | static int __init genhd_device_init(void) | |
794 | { | |
795 | int error; | |
796 | ||
797 | block_class.dev_kobj = sysfs_dev_block_kobj; | |
798 | error = class_register(&block_class); | |
799 | if (unlikely(error)) | |
800 | return error; | |
801 | bdev_map = kobj_map_init(base_probe, &block_class_lock); | |
802 | blk_dev_init(); | |
803 | ||
804 | register_blkdev(BLOCK_EXT_MAJOR, "blkext"); | |
805 | ||
806 | #ifndef CONFIG_SYSFS_DEPRECATED | |
807 | /* create top-level block dir */ | |
808 | block_depr = kobject_create_and_add("block", NULL); | |
809 | #endif | |
810 | return 0; | |
811 | } | |
812 | ||
813 | subsys_initcall(genhd_device_init); | |
814 | ||
815 | static ssize_t disk_range_show(struct device *dev, | |
816 | struct device_attribute *attr, char *buf) | |
817 | { | |
818 | struct gendisk *disk = dev_to_disk(dev); | |
819 | ||
820 | return sprintf(buf, "%d\n", disk->minors); | |
821 | } | |
822 | ||
823 | static ssize_t disk_ext_range_show(struct device *dev, | |
824 | struct device_attribute *attr, char *buf) | |
825 | { | |
826 | struct gendisk *disk = dev_to_disk(dev); | |
827 | ||
828 | return sprintf(buf, "%d\n", disk_max_parts(disk)); | |
829 | } | |
830 | ||
831 | static ssize_t disk_removable_show(struct device *dev, | |
832 | struct device_attribute *attr, char *buf) | |
833 | { | |
834 | struct gendisk *disk = dev_to_disk(dev); | |
835 | ||
836 | return sprintf(buf, "%d\n", | |
837 | (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0)); | |
838 | } | |
839 | ||
840 | static ssize_t disk_ro_show(struct device *dev, | |
841 | struct device_attribute *attr, char *buf) | |
842 | { | |
843 | struct gendisk *disk = dev_to_disk(dev); | |
844 | ||
845 | return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0); | |
846 | } | |
847 | ||
848 | static ssize_t disk_capability_show(struct device *dev, | |
849 | struct device_attribute *attr, char *buf) | |
850 | { | |
851 | struct gendisk *disk = dev_to_disk(dev); | |
852 | ||
853 | return sprintf(buf, "%x\n", disk->flags); | |
854 | } | |
855 | ||
856 | static ssize_t disk_alignment_offset_show(struct device *dev, | |
857 | struct device_attribute *attr, | |
858 | char *buf) | |
859 | { | |
860 | struct gendisk *disk = dev_to_disk(dev); | |
861 | ||
862 | return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue)); | |
863 | } | |
864 | ||
865 | static ssize_t disk_discard_alignment_show(struct device *dev, | |
866 | struct device_attribute *attr, | |
867 | char *buf) | |
868 | { | |
869 | struct gendisk *disk = dev_to_disk(dev); | |
870 | ||
871 | return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue)); | |
872 | } | |
873 | ||
874 | static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL); | |
875 | static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL); | |
876 | static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL); | |
877 | static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL); | |
878 | static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL); | |
879 | static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL); | |
880 | static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show, | |
881 | NULL); | |
882 | static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL); | |
883 | static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); | |
884 | static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); | |
885 | #ifdef CONFIG_FAIL_MAKE_REQUEST | |
886 | static struct device_attribute dev_attr_fail = | |
887 | __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store); | |
888 | #endif | |
889 | #ifdef CONFIG_FAIL_IO_TIMEOUT | |
890 | static struct device_attribute dev_attr_fail_timeout = | |
891 | __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show, | |
892 | part_timeout_store); | |
893 | #endif | |
894 | ||
895 | static struct attribute *disk_attrs[] = { | |
896 | &dev_attr_range.attr, | |
897 | &dev_attr_ext_range.attr, | |
898 | &dev_attr_removable.attr, | |
899 | &dev_attr_ro.attr, | |
900 | &dev_attr_size.attr, | |
901 | &dev_attr_alignment_offset.attr, | |
902 | &dev_attr_discard_alignment.attr, | |
903 | &dev_attr_capability.attr, | |
904 | &dev_attr_stat.attr, | |
905 | &dev_attr_inflight.attr, | |
906 | #ifdef CONFIG_FAIL_MAKE_REQUEST | |
907 | &dev_attr_fail.attr, | |
908 | #endif | |
909 | #ifdef CONFIG_FAIL_IO_TIMEOUT | |
910 | &dev_attr_fail_timeout.attr, | |
911 | #endif | |
912 | NULL | |
913 | }; | |
914 | ||
915 | static struct attribute_group disk_attr_group = { | |
916 | .attrs = disk_attrs, | |
917 | }; | |
918 | ||
919 | static const struct attribute_group *disk_attr_groups[] = { | |
920 | &disk_attr_group, | |
921 | NULL | |
922 | }; | |
923 | ||
924 | static void disk_free_ptbl_rcu_cb(struct rcu_head *head) | |
925 | { | |
926 | struct disk_part_tbl *ptbl = | |
927 | container_of(head, struct disk_part_tbl, rcu_head); | |
928 | ||
929 | kfree(ptbl); | |
930 | } | |
931 | ||
932 | /** | |
933 | * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way | |
934 | * @disk: disk to replace part_tbl for | |
935 | * @new_ptbl: new part_tbl to install | |
936 | * | |
937 | * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The | |
938 | * original ptbl is freed using RCU callback. | |
939 | * | |
940 | * LOCKING: | |
941 | * Matching bd_mutx locked. | |
942 | */ | |
943 | static void disk_replace_part_tbl(struct gendisk *disk, | |
944 | struct disk_part_tbl *new_ptbl) | |
945 | { | |
946 | struct disk_part_tbl *old_ptbl = disk->part_tbl; | |
947 | ||
948 | rcu_assign_pointer(disk->part_tbl, new_ptbl); | |
949 | ||
950 | if (old_ptbl) { | |
951 | rcu_assign_pointer(old_ptbl->last_lookup, NULL); | |
952 | call_rcu(&old_ptbl->rcu_head, disk_free_ptbl_rcu_cb); | |
953 | } | |
954 | } | |
955 | ||
956 | /** | |
957 | * disk_expand_part_tbl - expand disk->part_tbl | |
958 | * @disk: disk to expand part_tbl for | |
959 | * @partno: expand such that this partno can fit in | |
960 | * | |
961 | * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl | |
962 | * uses RCU to allow unlocked dereferencing for stats and other stuff. | |
963 | * | |
964 | * LOCKING: | |
965 | * Matching bd_mutex locked, might sleep. | |
966 | * | |
967 | * RETURNS: | |
968 | * 0 on success, -errno on failure. | |
969 | */ | |
970 | int disk_expand_part_tbl(struct gendisk *disk, int partno) | |
971 | { | |
972 | struct disk_part_tbl *old_ptbl = disk->part_tbl; | |
973 | struct disk_part_tbl *new_ptbl; | |
974 | int len = old_ptbl ? old_ptbl->len : 0; | |
975 | int target = partno + 1; | |
976 | size_t size; | |
977 | int i; | |
978 | ||
979 | /* disk_max_parts() is zero during initialization, ignore if so */ | |
980 | if (disk_max_parts(disk) && target > disk_max_parts(disk)) | |
981 | return -EINVAL; | |
982 | ||
983 | if (target <= len) | |
984 | return 0; | |
985 | ||
986 | size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]); | |
987 | new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id); | |
988 | if (!new_ptbl) | |
989 | return -ENOMEM; | |
990 | ||
991 | new_ptbl->len = target; | |
992 | ||
993 | for (i = 0; i < len; i++) | |
994 | rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]); | |
995 | ||
996 | disk_replace_part_tbl(disk, new_ptbl); | |
997 | return 0; | |
998 | } | |
999 | ||
1000 | static void disk_release(struct device *dev) | |
1001 | { | |
1002 | struct gendisk *disk = dev_to_disk(dev); | |
1003 | ||
1004 | kfree(disk->random); | |
1005 | disk_replace_part_tbl(disk, NULL); | |
1006 | free_part_stats(&disk->part0); | |
1007 | free_part_info(&disk->part0); | |
1008 | kfree(disk); | |
1009 | } | |
1010 | struct class block_class = { | |
1011 | .name = "block", | |
1012 | }; | |
1013 | ||
1014 | static char *block_devnode(struct device *dev, mode_t *mode) | |
1015 | { | |
1016 | struct gendisk *disk = dev_to_disk(dev); | |
1017 | ||
1018 | if (disk->devnode) | |
1019 | return disk->devnode(disk, mode); | |
1020 | return NULL; | |
1021 | } | |
1022 | ||
1023 | static struct device_type disk_type = { | |
1024 | .name = "disk", | |
1025 | .groups = disk_attr_groups, | |
1026 | .release = disk_release, | |
1027 | .devnode = block_devnode, | |
1028 | }; | |
1029 | ||
1030 | #ifdef CONFIG_PROC_FS | |
1031 | /* | |
1032 | * aggregate disk stat collector. Uses the same stats that the sysfs | |
1033 | * entries do, above, but makes them available through one seq_file. | |
1034 | * | |
1035 | * The output looks suspiciously like /proc/partitions with a bunch of | |
1036 | * extra fields. | |
1037 | */ | |
1038 | static int diskstats_show(struct seq_file *seqf, void *v) | |
1039 | { | |
1040 | struct gendisk *gp = v; | |
1041 | struct disk_part_iter piter; | |
1042 | struct hd_struct *hd; | |
1043 | char buf[BDEVNAME_SIZE]; | |
1044 | int cpu; | |
1045 | ||
1046 | /* | |
1047 | if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next) | |
1048 | seq_puts(seqf, "major minor name" | |
1049 | " rio rmerge rsect ruse wio wmerge " | |
1050 | "wsect wuse running use aveq" | |
1051 | "\n\n"); | |
1052 | */ | |
1053 | ||
1054 | disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0); | |
1055 | while ((hd = disk_part_iter_next(&piter))) { | |
1056 | cpu = part_stat_lock(); | |
1057 | part_round_stats(cpu, hd); | |
1058 | part_stat_unlock(); | |
1059 | seq_printf(seqf, "%4d %7d %s %lu %lu %llu " | |
1060 | "%u %lu %lu %llu %u %u %u %u\n", | |
1061 | MAJOR(part_devt(hd)), MINOR(part_devt(hd)), | |
1062 | disk_name(gp, hd->partno, buf), | |
1063 | part_stat_read(hd, ios[0]), | |
1064 | part_stat_read(hd, merges[0]), | |
1065 | (unsigned long long)part_stat_read(hd, sectors[0]), | |
1066 | jiffies_to_msecs(part_stat_read(hd, ticks[0])), | |
1067 | part_stat_read(hd, ios[1]), | |
1068 | part_stat_read(hd, merges[1]), | |
1069 | (unsigned long long)part_stat_read(hd, sectors[1]), | |
1070 | jiffies_to_msecs(part_stat_read(hd, ticks[1])), | |
1071 | part_in_flight(hd), | |
1072 | jiffies_to_msecs(part_stat_read(hd, io_ticks)), | |
1073 | jiffies_to_msecs(part_stat_read(hd, time_in_queue)) | |
1074 | ); | |
1075 | } | |
1076 | disk_part_iter_exit(&piter); | |
1077 | ||
1078 | return 0; | |
1079 | } | |
1080 | ||
1081 | static const struct seq_operations diskstats_op = { | |
1082 | .start = disk_seqf_start, | |
1083 | .next = disk_seqf_next, | |
1084 | .stop = disk_seqf_stop, | |
1085 | .show = diskstats_show | |
1086 | }; | |
1087 | ||
1088 | static int diskstats_open(struct inode *inode, struct file *file) | |
1089 | { | |
1090 | return seq_open(file, &diskstats_op); | |
1091 | } | |
1092 | ||
1093 | static const struct file_operations proc_diskstats_operations = { | |
1094 | .open = diskstats_open, | |
1095 | .read = seq_read, | |
1096 | .llseek = seq_lseek, | |
1097 | .release = seq_release, | |
1098 | }; | |
1099 | ||
1100 | static int __init proc_genhd_init(void) | |
1101 | { | |
1102 | proc_create("diskstats", 0, NULL, &proc_diskstats_operations); | |
1103 | proc_create("partitions", 0, NULL, &proc_partitions_operations); | |
1104 | return 0; | |
1105 | } | |
1106 | module_init(proc_genhd_init); | |
1107 | #endif /* CONFIG_PROC_FS */ | |
1108 | ||
1109 | static void media_change_notify_thread(struct work_struct *work) | |
1110 | { | |
1111 | struct gendisk *gd = container_of(work, struct gendisk, async_notify); | |
1112 | char event[] = "MEDIA_CHANGE=1"; | |
1113 | char *envp[] = { event, NULL }; | |
1114 | ||
1115 | /* | |
1116 | * set enviroment vars to indicate which event this is for | |
1117 | * so that user space will know to go check the media status. | |
1118 | */ | |
1119 | kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp); | |
1120 | put_device(gd->driverfs_dev); | |
1121 | } | |
1122 | ||
1123 | #if 0 | |
1124 | void genhd_media_change_notify(struct gendisk *disk) | |
1125 | { | |
1126 | get_device(disk->driverfs_dev); | |
1127 | schedule_work(&disk->async_notify); | |
1128 | } | |
1129 | EXPORT_SYMBOL_GPL(genhd_media_change_notify); | |
1130 | #endif /* 0 */ | |
1131 | ||
1132 | dev_t blk_lookup_devt(const char *name, int partno) | |
1133 | { | |
1134 | dev_t devt = MKDEV(0, 0); | |
1135 | struct class_dev_iter iter; | |
1136 | struct device *dev; | |
1137 | ||
1138 | class_dev_iter_init(&iter, &block_class, NULL, &disk_type); | |
1139 | while ((dev = class_dev_iter_next(&iter))) { | |
1140 | struct gendisk *disk = dev_to_disk(dev); | |
1141 | struct hd_struct *part; | |
1142 | ||
1143 | if (strcmp(dev_name(dev), name)) | |
1144 | continue; | |
1145 | ||
1146 | if (partno < disk->minors) { | |
1147 | /* We need to return the right devno, even | |
1148 | * if the partition doesn't exist yet. | |
1149 | */ | |
1150 | devt = MKDEV(MAJOR(dev->devt), | |
1151 | MINOR(dev->devt) + partno); | |
1152 | break; | |
1153 | } | |
1154 | part = disk_get_part(disk, partno); | |
1155 | if (part) { | |
1156 | devt = part_devt(part); | |
1157 | disk_put_part(part); | |
1158 | break; | |
1159 | } | |
1160 | disk_put_part(part); | |
1161 | } | |
1162 | class_dev_iter_exit(&iter); | |
1163 | return devt; | |
1164 | } | |
1165 | EXPORT_SYMBOL(blk_lookup_devt); | |
1166 | ||
1167 | struct gendisk *alloc_disk(int minors) | |
1168 | { | |
1169 | return alloc_disk_node(minors, -1); | |
1170 | } | |
1171 | EXPORT_SYMBOL(alloc_disk); | |
1172 | ||
1173 | struct gendisk *alloc_disk_node(int minors, int node_id) | |
1174 | { | |
1175 | struct gendisk *disk; | |
1176 | ||
1177 | disk = kmalloc_node(sizeof(struct gendisk), | |
1178 | GFP_KERNEL | __GFP_ZERO, node_id); | |
1179 | if (disk) { | |
1180 | if (!init_part_stats(&disk->part0)) { | |
1181 | kfree(disk); | |
1182 | return NULL; | |
1183 | } | |
1184 | disk->node_id = node_id; | |
1185 | if (disk_expand_part_tbl(disk, 0)) { | |
1186 | free_part_stats(&disk->part0); | |
1187 | kfree(disk); | |
1188 | return NULL; | |
1189 | } | |
1190 | disk->part_tbl->part[0] = &disk->part0; | |
1191 | ||
1192 | disk->minors = minors; | |
1193 | rand_initialize_disk(disk); | |
1194 | disk_to_dev(disk)->class = &block_class; | |
1195 | disk_to_dev(disk)->type = &disk_type; | |
1196 | device_initialize(disk_to_dev(disk)); | |
1197 | INIT_WORK(&disk->async_notify, | |
1198 | media_change_notify_thread); | |
1199 | } | |
1200 | return disk; | |
1201 | } | |
1202 | EXPORT_SYMBOL(alloc_disk_node); | |
1203 | ||
1204 | struct kobject *get_disk(struct gendisk *disk) | |
1205 | { | |
1206 | struct module *owner; | |
1207 | struct kobject *kobj; | |
1208 | ||
1209 | if (!disk->fops) | |
1210 | return NULL; | |
1211 | owner = disk->fops->owner; | |
1212 | if (owner && !try_module_get(owner)) | |
1213 | return NULL; | |
1214 | kobj = kobject_get(&disk_to_dev(disk)->kobj); | |
1215 | if (kobj == NULL) { | |
1216 | module_put(owner); | |
1217 | return NULL; | |
1218 | } | |
1219 | return kobj; | |
1220 | ||
1221 | } | |
1222 | ||
1223 | EXPORT_SYMBOL(get_disk); | |
1224 | ||
1225 | void put_disk(struct gendisk *disk) | |
1226 | { | |
1227 | if (disk) | |
1228 | kobject_put(&disk_to_dev(disk)->kobj); | |
1229 | } | |
1230 | ||
1231 | EXPORT_SYMBOL(put_disk); | |
1232 | ||
1233 | static void set_disk_ro_uevent(struct gendisk *gd, int ro) | |
1234 | { | |
1235 | char event[] = "DISK_RO=1"; | |
1236 | char *envp[] = { event, NULL }; | |
1237 | ||
1238 | if (!ro) | |
1239 | event[8] = '0'; | |
1240 | kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp); | |
1241 | } | |
1242 | ||
1243 | void set_device_ro(struct block_device *bdev, int flag) | |
1244 | { | |
1245 | bdev->bd_part->policy = flag; | |
1246 | } | |
1247 | ||
1248 | EXPORT_SYMBOL(set_device_ro); | |
1249 | ||
1250 | void set_disk_ro(struct gendisk *disk, int flag) | |
1251 | { | |
1252 | struct disk_part_iter piter; | |
1253 | struct hd_struct *part; | |
1254 | ||
1255 | if (disk->part0.policy != flag) { | |
1256 | set_disk_ro_uevent(disk, flag); | |
1257 | disk->part0.policy = flag; | |
1258 | } | |
1259 | ||
1260 | disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); | |
1261 | while ((part = disk_part_iter_next(&piter))) | |
1262 | part->policy = flag; | |
1263 | disk_part_iter_exit(&piter); | |
1264 | } | |
1265 | ||
1266 | EXPORT_SYMBOL(set_disk_ro); | |
1267 | ||
1268 | int bdev_read_only(struct block_device *bdev) | |
1269 | { | |
1270 | if (!bdev) | |
1271 | return 0; | |
1272 | return bdev->bd_part->policy; | |
1273 | } | |
1274 | ||
1275 | EXPORT_SYMBOL(bdev_read_only); | |
1276 | ||
1277 | int invalidate_partition(struct gendisk *disk, int partno) | |
1278 | { | |
1279 | int res = 0; | |
1280 | struct block_device *bdev = bdget_disk(disk, partno); | |
1281 | if (bdev) { | |
1282 | fsync_bdev(bdev); | |
1283 | res = __invalidate_device(bdev); | |
1284 | bdput(bdev); | |
1285 | } | |
1286 | return res; | |
1287 | } | |
1288 | ||
1289 | EXPORT_SYMBOL(invalidate_partition); |