Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * gendisk handling | |
3 | */ | |
4 | ||
1da177e4 LT |
5 | #include <linux/module.h> |
6 | #include <linux/fs.h> | |
7 | #include <linux/genhd.h> | |
b446b60e | 8 | #include <linux/kdev_t.h> |
1da177e4 LT |
9 | #include <linux/kernel.h> |
10 | #include <linux/blkdev.h> | |
11 | #include <linux/init.h> | |
12 | #include <linux/spinlock.h> | |
f500975a | 13 | #include <linux/proc_fs.h> |
1da177e4 LT |
14 | #include <linux/seq_file.h> |
15 | #include <linux/slab.h> | |
16 | #include <linux/kmod.h> | |
17 | #include <linux/kobj_map.h> | |
58383af6 | 18 | #include <linux/mutex.h> |
bcce3de1 | 19 | #include <linux/idr.h> |
77ea887e | 20 | #include <linux/log2.h> |
25e823c8 | 21 | #include <linux/pm_runtime.h> |
1da177e4 | 22 | |
ff88972c AB |
23 | #include "blk.h" |
24 | ||
edfaa7c3 | 25 | static DEFINE_MUTEX(block_class_lock); |
edfaa7c3 | 26 | struct kobject *block_depr; |
1da177e4 | 27 | |
bcce3de1 TH |
28 | /* for extended dynamic devt allocation, currently only one major is used */ |
29 | #define MAX_EXT_DEVT (1 << MINORBITS) | |
30 | ||
31 | /* For extended devt allocation. ext_devt_mutex prevents look up | |
32 | * results from going away underneath its user. | |
33 | */ | |
34 | static DEFINE_MUTEX(ext_devt_mutex); | |
35 | static DEFINE_IDR(ext_devt_idr); | |
36 | ||
1826eadf AB |
37 | static struct device_type disk_type; |
38 | ||
12c2bdb2 DB |
39 | static void disk_check_events(struct disk_events *ev, |
40 | unsigned int *clearing_ptr); | |
9f53d2fe | 41 | static void disk_alloc_events(struct gendisk *disk); |
77ea887e TH |
42 | static void disk_add_events(struct gendisk *disk); |
43 | static void disk_del_events(struct gendisk *disk); | |
44 | static void disk_release_events(struct gendisk *disk); | |
45 | ||
e71bf0d0 TH |
46 | /** |
47 | * disk_get_part - get partition | |
48 | * @disk: disk to look partition from | |
49 | * @partno: partition number | |
50 | * | |
51 | * Look for partition @partno from @disk. If found, increment | |
52 | * reference count and return it. | |
53 | * | |
54 | * CONTEXT: | |
55 | * Don't care. | |
56 | * | |
57 | * RETURNS: | |
58 | * Pointer to the found partition on success, NULL if not found. | |
59 | */ | |
60 | struct hd_struct *disk_get_part(struct gendisk *disk, int partno) | |
61 | { | |
540eed56 TH |
62 | struct hd_struct *part = NULL; |
63 | struct disk_part_tbl *ptbl; | |
e71bf0d0 | 64 | |
540eed56 | 65 | if (unlikely(partno < 0)) |
e71bf0d0 | 66 | return NULL; |
540eed56 | 67 | |
e71bf0d0 | 68 | rcu_read_lock(); |
540eed56 TH |
69 | |
70 | ptbl = rcu_dereference(disk->part_tbl); | |
71 | if (likely(partno < ptbl->len)) { | |
72 | part = rcu_dereference(ptbl->part[partno]); | |
73 | if (part) | |
74 | get_device(part_to_dev(part)); | |
75 | } | |
76 | ||
e71bf0d0 TH |
77 | rcu_read_unlock(); |
78 | ||
79 | return part; | |
80 | } | |
81 | EXPORT_SYMBOL_GPL(disk_get_part); | |
82 | ||
83 | /** | |
84 | * disk_part_iter_init - initialize partition iterator | |
85 | * @piter: iterator to initialize | |
86 | * @disk: disk to iterate over | |
87 | * @flags: DISK_PITER_* flags | |
88 | * | |
89 | * Initialize @piter so that it iterates over partitions of @disk. | |
90 | * | |
91 | * CONTEXT: | |
92 | * Don't care. | |
93 | */ | |
94 | void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk, | |
95 | unsigned int flags) | |
96 | { | |
540eed56 TH |
97 | struct disk_part_tbl *ptbl; |
98 | ||
99 | rcu_read_lock(); | |
100 | ptbl = rcu_dereference(disk->part_tbl); | |
101 | ||
e71bf0d0 TH |
102 | piter->disk = disk; |
103 | piter->part = NULL; | |
104 | ||
105 | if (flags & DISK_PITER_REVERSE) | |
540eed56 | 106 | piter->idx = ptbl->len - 1; |
71982a40 | 107 | else if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0)) |
e71bf0d0 | 108 | piter->idx = 0; |
b5d0b9df TH |
109 | else |
110 | piter->idx = 1; | |
e71bf0d0 TH |
111 | |
112 | piter->flags = flags; | |
540eed56 TH |
113 | |
114 | rcu_read_unlock(); | |
e71bf0d0 TH |
115 | } |
116 | EXPORT_SYMBOL_GPL(disk_part_iter_init); | |
117 | ||
118 | /** | |
119 | * disk_part_iter_next - proceed iterator to the next partition and return it | |
120 | * @piter: iterator of interest | |
121 | * | |
122 | * Proceed @piter to the next partition and return it. | |
123 | * | |
124 | * CONTEXT: | |
125 | * Don't care. | |
126 | */ | |
127 | struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter) | |
128 | { | |
540eed56 | 129 | struct disk_part_tbl *ptbl; |
e71bf0d0 TH |
130 | int inc, end; |
131 | ||
132 | /* put the last partition */ | |
133 | disk_put_part(piter->part); | |
134 | piter->part = NULL; | |
135 | ||
540eed56 | 136 | /* get part_tbl */ |
e71bf0d0 | 137 | rcu_read_lock(); |
540eed56 | 138 | ptbl = rcu_dereference(piter->disk->part_tbl); |
e71bf0d0 TH |
139 | |
140 | /* determine iteration parameters */ | |
141 | if (piter->flags & DISK_PITER_REVERSE) { | |
142 | inc = -1; | |
71982a40 TH |
143 | if (piter->flags & (DISK_PITER_INCL_PART0 | |
144 | DISK_PITER_INCL_EMPTY_PART0)) | |
b5d0b9df TH |
145 | end = -1; |
146 | else | |
147 | end = 0; | |
e71bf0d0 TH |
148 | } else { |
149 | inc = 1; | |
540eed56 | 150 | end = ptbl->len; |
e71bf0d0 TH |
151 | } |
152 | ||
153 | /* iterate to the next partition */ | |
154 | for (; piter->idx != end; piter->idx += inc) { | |
155 | struct hd_struct *part; | |
156 | ||
540eed56 | 157 | part = rcu_dereference(ptbl->part[piter->idx]); |
e71bf0d0 TH |
158 | if (!part) |
159 | continue; | |
c83f6bf9 | 160 | if (!part_nr_sects_read(part) && |
71982a40 TH |
161 | !(piter->flags & DISK_PITER_INCL_EMPTY) && |
162 | !(piter->flags & DISK_PITER_INCL_EMPTY_PART0 && | |
163 | piter->idx == 0)) | |
e71bf0d0 TH |
164 | continue; |
165 | ||
ed9e1982 | 166 | get_device(part_to_dev(part)); |
e71bf0d0 TH |
167 | piter->part = part; |
168 | piter->idx += inc; | |
169 | break; | |
170 | } | |
171 | ||
172 | rcu_read_unlock(); | |
173 | ||
174 | return piter->part; | |
175 | } | |
176 | EXPORT_SYMBOL_GPL(disk_part_iter_next); | |
177 | ||
178 | /** | |
179 | * disk_part_iter_exit - finish up partition iteration | |
180 | * @piter: iter of interest | |
181 | * | |
182 | * Called when iteration is over. Cleans up @piter. | |
183 | * | |
184 | * CONTEXT: | |
185 | * Don't care. | |
186 | */ | |
187 | void disk_part_iter_exit(struct disk_part_iter *piter) | |
188 | { | |
189 | disk_put_part(piter->part); | |
190 | piter->part = NULL; | |
191 | } | |
192 | EXPORT_SYMBOL_GPL(disk_part_iter_exit); | |
193 | ||
a6f23657 JA |
194 | static inline int sector_in_part(struct hd_struct *part, sector_t sector) |
195 | { | |
196 | return part->start_sect <= sector && | |
c83f6bf9 | 197 | sector < part->start_sect + part_nr_sects_read(part); |
a6f23657 JA |
198 | } |
199 | ||
e71bf0d0 TH |
200 | /** |
201 | * disk_map_sector_rcu - map sector to partition | |
202 | * @disk: gendisk of interest | |
203 | * @sector: sector to map | |
204 | * | |
205 | * Find out which partition @sector maps to on @disk. This is | |
206 | * primarily used for stats accounting. | |
207 | * | |
208 | * CONTEXT: | |
209 | * RCU read locked. The returned partition pointer is valid only | |
210 | * while preemption is disabled. | |
211 | * | |
212 | * RETURNS: | |
074a7aca | 213 | * Found partition on success, part0 is returned if no partition matches |
e71bf0d0 TH |
214 | */ |
215 | struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) | |
216 | { | |
540eed56 | 217 | struct disk_part_tbl *ptbl; |
a6f23657 | 218 | struct hd_struct *part; |
e71bf0d0 TH |
219 | int i; |
220 | ||
540eed56 TH |
221 | ptbl = rcu_dereference(disk->part_tbl); |
222 | ||
a6f23657 JA |
223 | part = rcu_dereference(ptbl->last_lookup); |
224 | if (part && sector_in_part(part, sector)) | |
225 | return part; | |
226 | ||
540eed56 | 227 | for (i = 1; i < ptbl->len; i++) { |
a6f23657 | 228 | part = rcu_dereference(ptbl->part[i]); |
e71bf0d0 | 229 | |
a6f23657 JA |
230 | if (part && sector_in_part(part, sector)) { |
231 | rcu_assign_pointer(ptbl->last_lookup, part); | |
e71bf0d0 | 232 | return part; |
a6f23657 | 233 | } |
e71bf0d0 | 234 | } |
074a7aca | 235 | return &disk->part0; |
e71bf0d0 TH |
236 | } |
237 | EXPORT_SYMBOL_GPL(disk_map_sector_rcu); | |
238 | ||
1da177e4 LT |
239 | /* |
240 | * Can be deleted altogether. Later. | |
241 | * | |
242 | */ | |
243 | static struct blk_major_name { | |
244 | struct blk_major_name *next; | |
245 | int major; | |
246 | char name[16]; | |
68eef3b4 | 247 | } *major_names[BLKDEV_MAJOR_HASH_SIZE]; |
1da177e4 LT |
248 | |
249 | /* index in the above - for now: assume no multimajor ranges */ | |
e61eb2e9 | 250 | static inline int major_to_index(unsigned major) |
1da177e4 | 251 | { |
68eef3b4 | 252 | return major % BLKDEV_MAJOR_HASH_SIZE; |
7170be5f NH |
253 | } |
254 | ||
68eef3b4 | 255 | #ifdef CONFIG_PROC_FS |
cf771cb5 | 256 | void blkdev_show(struct seq_file *seqf, off_t offset) |
7170be5f | 257 | { |
68eef3b4 | 258 | struct blk_major_name *dp; |
7170be5f | 259 | |
68eef3b4 | 260 | if (offset < BLKDEV_MAJOR_HASH_SIZE) { |
edfaa7c3 | 261 | mutex_lock(&block_class_lock); |
68eef3b4 | 262 | for (dp = major_names[offset]; dp; dp = dp->next) |
cf771cb5 | 263 | seq_printf(seqf, "%3d %s\n", dp->major, dp->name); |
edfaa7c3 | 264 | mutex_unlock(&block_class_lock); |
1da177e4 | 265 | } |
1da177e4 | 266 | } |
68eef3b4 | 267 | #endif /* CONFIG_PROC_FS */ |
1da177e4 | 268 | |
9e8c0bcc MN |
269 | /** |
270 | * register_blkdev - register a new block device | |
271 | * | |
272 | * @major: the requested major device number [1..255]. If @major=0, try to | |
273 | * allocate any unused major number. | |
274 | * @name: the name of the new block device as a zero terminated string | |
275 | * | |
276 | * The @name must be unique within the system. | |
277 | * | |
278 | * The return value depends on the @major input parameter. | |
279 | * - if a major device number was requested in range [1..255] then the | |
280 | * function returns zero on success, or a negative error code | |
281 | * - if any unused major number was requested with @major=0 parameter | |
282 | * then the return value is the allocated major number in range | |
283 | * [1..255] or a negative error code otherwise | |
284 | */ | |
1da177e4 LT |
285 | int register_blkdev(unsigned int major, const char *name) |
286 | { | |
287 | struct blk_major_name **n, *p; | |
288 | int index, ret = 0; | |
289 | ||
edfaa7c3 | 290 | mutex_lock(&block_class_lock); |
1da177e4 LT |
291 | |
292 | /* temporary */ | |
293 | if (major == 0) { | |
294 | for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) { | |
295 | if (major_names[index] == NULL) | |
296 | break; | |
297 | } | |
298 | ||
299 | if (index == 0) { | |
300 | printk("register_blkdev: failed to get major for %s\n", | |
301 | name); | |
302 | ret = -EBUSY; | |
303 | goto out; | |
304 | } | |
305 | major = index; | |
306 | ret = major; | |
307 | } | |
308 | ||
309 | p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL); | |
310 | if (p == NULL) { | |
311 | ret = -ENOMEM; | |
312 | goto out; | |
313 | } | |
314 | ||
315 | p->major = major; | |
316 | strlcpy(p->name, name, sizeof(p->name)); | |
317 | p->next = NULL; | |
318 | index = major_to_index(major); | |
319 | ||
320 | for (n = &major_names[index]; *n; n = &(*n)->next) { | |
321 | if ((*n)->major == major) | |
322 | break; | |
323 | } | |
324 | if (!*n) | |
325 | *n = p; | |
326 | else | |
327 | ret = -EBUSY; | |
328 | ||
329 | if (ret < 0) { | |
330 | printk("register_blkdev: cannot get major %d for %s\n", | |
331 | major, name); | |
332 | kfree(p); | |
333 | } | |
334 | out: | |
edfaa7c3 | 335 | mutex_unlock(&block_class_lock); |
1da177e4 LT |
336 | return ret; |
337 | } | |
338 | ||
339 | EXPORT_SYMBOL(register_blkdev); | |
340 | ||
f4480240 | 341 | void unregister_blkdev(unsigned int major, const char *name) |
1da177e4 LT |
342 | { |
343 | struct blk_major_name **n; | |
344 | struct blk_major_name *p = NULL; | |
345 | int index = major_to_index(major); | |
1da177e4 | 346 | |
edfaa7c3 | 347 | mutex_lock(&block_class_lock); |
1da177e4 LT |
348 | for (n = &major_names[index]; *n; n = &(*n)->next) |
349 | if ((*n)->major == major) | |
350 | break; | |
294462a5 AM |
351 | if (!*n || strcmp((*n)->name, name)) { |
352 | WARN_ON(1); | |
294462a5 | 353 | } else { |
1da177e4 LT |
354 | p = *n; |
355 | *n = p->next; | |
356 | } | |
edfaa7c3 | 357 | mutex_unlock(&block_class_lock); |
1da177e4 | 358 | kfree(p); |
1da177e4 LT |
359 | } |
360 | ||
361 | EXPORT_SYMBOL(unregister_blkdev); | |
362 | ||
363 | static struct kobj_map *bdev_map; | |
364 | ||
870d6656 TH |
365 | /** |
366 | * blk_mangle_minor - scatter minor numbers apart | |
367 | * @minor: minor number to mangle | |
368 | * | |
369 | * Scatter consecutively allocated @minor number apart if MANGLE_DEVT | |
370 | * is enabled. Mangling twice gives the original value. | |
371 | * | |
372 | * RETURNS: | |
373 | * Mangled value. | |
374 | * | |
375 | * CONTEXT: | |
376 | * Don't care. | |
377 | */ | |
378 | static int blk_mangle_minor(int minor) | |
379 | { | |
380 | #ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT | |
381 | int i; | |
382 | ||
383 | for (i = 0; i < MINORBITS / 2; i++) { | |
384 | int low = minor & (1 << i); | |
385 | int high = minor & (1 << (MINORBITS - 1 - i)); | |
386 | int distance = MINORBITS - 1 - 2 * i; | |
387 | ||
388 | minor ^= low | high; /* clear both bits */ | |
389 | low <<= distance; /* swap the positions */ | |
390 | high >>= distance; | |
391 | minor |= low | high; /* and set */ | |
392 | } | |
393 | #endif | |
394 | return minor; | |
395 | } | |
396 | ||
bcce3de1 TH |
397 | /** |
398 | * blk_alloc_devt - allocate a dev_t for a partition | |
399 | * @part: partition to allocate dev_t for | |
bcce3de1 TH |
400 | * @devt: out parameter for resulting dev_t |
401 | * | |
402 | * Allocate a dev_t for block device. | |
403 | * | |
404 | * RETURNS: | |
405 | * 0 on success, allocated dev_t is returned in *@devt. -errno on | |
406 | * failure. | |
407 | * | |
408 | * CONTEXT: | |
409 | * Might sleep. | |
410 | */ | |
411 | int blk_alloc_devt(struct hd_struct *part, dev_t *devt) | |
412 | { | |
413 | struct gendisk *disk = part_to_disk(part); | |
414 | int idx, rc; | |
415 | ||
416 | /* in consecutive minor range? */ | |
417 | if (part->partno < disk->minors) { | |
418 | *devt = MKDEV(disk->major, disk->first_minor + part->partno); | |
419 | return 0; | |
420 | } | |
421 | ||
422 | /* allocate ext devt */ | |
423 | do { | |
424 | if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL)) | |
425 | return -ENOMEM; | |
7b74e912 | 426 | mutex_lock(&ext_devt_mutex); |
bcce3de1 | 427 | rc = idr_get_new(&ext_devt_idr, part, &idx); |
7b74e912 | 428 | mutex_unlock(&ext_devt_mutex); |
bcce3de1 TH |
429 | } while (rc == -EAGAIN); |
430 | ||
431 | if (rc) | |
432 | return rc; | |
433 | ||
434 | if (idx > MAX_EXT_DEVT) { | |
7b74e912 | 435 | mutex_lock(&ext_devt_mutex); |
bcce3de1 | 436 | idr_remove(&ext_devt_idr, idx); |
7b74e912 | 437 | mutex_unlock(&ext_devt_mutex); |
bcce3de1 TH |
438 | return -EBUSY; |
439 | } | |
440 | ||
870d6656 | 441 | *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx)); |
bcce3de1 TH |
442 | return 0; |
443 | } | |
444 | ||
445 | /** | |
446 | * blk_free_devt - free a dev_t | |
447 | * @devt: dev_t to free | |
448 | * | |
449 | * Free @devt which was allocated using blk_alloc_devt(). | |
450 | * | |
451 | * CONTEXT: | |
452 | * Might sleep. | |
453 | */ | |
454 | void blk_free_devt(dev_t devt) | |
455 | { | |
456 | might_sleep(); | |
457 | ||
458 | if (devt == MKDEV(0, 0)) | |
459 | return; | |
460 | ||
461 | if (MAJOR(devt) == BLOCK_EXT_MAJOR) { | |
462 | mutex_lock(&ext_devt_mutex); | |
870d6656 | 463 | idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt))); |
bcce3de1 TH |
464 | mutex_unlock(&ext_devt_mutex); |
465 | } | |
466 | } | |
467 | ||
1f014290 TH |
468 | static char *bdevt_str(dev_t devt, char *buf) |
469 | { | |
470 | if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) { | |
471 | char tbuf[BDEVT_SIZE]; | |
472 | snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt)); | |
473 | snprintf(buf, BDEVT_SIZE, "%-9s", tbuf); | |
474 | } else | |
475 | snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt)); | |
476 | ||
477 | return buf; | |
478 | } | |
479 | ||
1da177e4 LT |
480 | /* |
481 | * Register device numbers dev..(dev+range-1) | |
482 | * range must be nonzero | |
483 | * The hash chain is sorted on range, so that subranges can override. | |
484 | */ | |
edfaa7c3 | 485 | void blk_register_region(dev_t devt, unsigned long range, struct module *module, |
1da177e4 LT |
486 | struct kobject *(*probe)(dev_t, int *, void *), |
487 | int (*lock)(dev_t, void *), void *data) | |
488 | { | |
edfaa7c3 | 489 | kobj_map(bdev_map, devt, range, module, probe, lock, data); |
1da177e4 LT |
490 | } |
491 | ||
492 | EXPORT_SYMBOL(blk_register_region); | |
493 | ||
edfaa7c3 | 494 | void blk_unregister_region(dev_t devt, unsigned long range) |
1da177e4 | 495 | { |
edfaa7c3 | 496 | kobj_unmap(bdev_map, devt, range); |
1da177e4 LT |
497 | } |
498 | ||
499 | EXPORT_SYMBOL(blk_unregister_region); | |
500 | ||
cf771cb5 | 501 | static struct kobject *exact_match(dev_t devt, int *partno, void *data) |
1da177e4 LT |
502 | { |
503 | struct gendisk *p = data; | |
edfaa7c3 | 504 | |
ed9e1982 | 505 | return &disk_to_dev(p)->kobj; |
1da177e4 LT |
506 | } |
507 | ||
edfaa7c3 | 508 | static int exact_lock(dev_t devt, void *data) |
1da177e4 LT |
509 | { |
510 | struct gendisk *p = data; | |
511 | ||
512 | if (!get_disk(p)) | |
513 | return -1; | |
514 | return 0; | |
515 | } | |
516 | ||
4752bc30 | 517 | static void register_disk(struct gendisk *disk) |
d2bf1b67 TH |
518 | { |
519 | struct device *ddev = disk_to_dev(disk); | |
520 | struct block_device *bdev; | |
521 | struct disk_part_iter piter; | |
522 | struct hd_struct *part; | |
523 | int err; | |
524 | ||
525 | ddev->parent = disk->driverfs_dev; | |
526 | ||
527 | dev_set_name(ddev, disk->disk_name); | |
528 | ||
529 | /* delay uevents, until we scanned partition table */ | |
530 | dev_set_uevent_suppress(ddev, 1); | |
531 | ||
532 | if (device_add(ddev)) | |
533 | return; | |
534 | if (!sysfs_deprecated) { | |
535 | err = sysfs_create_link(block_depr, &ddev->kobj, | |
536 | kobject_name(&ddev->kobj)); | |
537 | if (err) { | |
538 | device_del(ddev); | |
539 | return; | |
540 | } | |
541 | } | |
25e823c8 ML |
542 | |
543 | /* | |
544 | * avoid probable deadlock caused by allocating memory with | |
545 | * GFP_KERNEL in runtime_resume callback of its all ancestor | |
546 | * devices | |
547 | */ | |
548 | pm_runtime_set_memalloc_noio(ddev, true); | |
549 | ||
d2bf1b67 TH |
550 | disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj); |
551 | disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj); | |
552 | ||
553 | /* No minors to use for partitions */ | |
d27769ec | 554 | if (!disk_part_scan_enabled(disk)) |
d2bf1b67 TH |
555 | goto exit; |
556 | ||
557 | /* No such device (e.g., media were just removed) */ | |
558 | if (!get_capacity(disk)) | |
559 | goto exit; | |
560 | ||
561 | bdev = bdget_disk(disk, 0); | |
562 | if (!bdev) | |
563 | goto exit; | |
564 | ||
565 | bdev->bd_invalidated = 1; | |
566 | err = blkdev_get(bdev, FMODE_READ, NULL); | |
567 | if (err < 0) | |
568 | goto exit; | |
569 | blkdev_put(bdev, FMODE_READ); | |
570 | ||
571 | exit: | |
572 | /* announce disk after possible partitions are created */ | |
573 | dev_set_uevent_suppress(ddev, 0); | |
574 | kobject_uevent(&ddev->kobj, KOBJ_ADD); | |
575 | ||
576 | /* announce possible partitions */ | |
577 | disk_part_iter_init(&piter, disk, 0); | |
578 | while ((part = disk_part_iter_next(&piter))) | |
579 | kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD); | |
580 | disk_part_iter_exit(&piter); | |
581 | } | |
582 | ||
1da177e4 LT |
583 | /** |
584 | * add_disk - add partitioning information to kernel list | |
585 | * @disk: per-device partitioning information | |
586 | * | |
587 | * This function registers the partitioning information in @disk | |
588 | * with the kernel. | |
3e1a7ff8 TH |
589 | * |
590 | * FIXME: error handling | |
1da177e4 LT |
591 | */ |
592 | void add_disk(struct gendisk *disk) | |
593 | { | |
cf0ca9fe | 594 | struct backing_dev_info *bdi; |
3e1a7ff8 | 595 | dev_t devt; |
6ffeea77 | 596 | int retval; |
cf0ca9fe | 597 | |
3e1a7ff8 TH |
598 | /* minors == 0 indicates to use ext devt from part0 and should |
599 | * be accompanied with EXT_DEVT flag. Make sure all | |
600 | * parameters make sense. | |
601 | */ | |
602 | WARN_ON(disk->minors && !(disk->major || disk->first_minor)); | |
603 | WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT)); | |
604 | ||
1da177e4 | 605 | disk->flags |= GENHD_FL_UP; |
3e1a7ff8 TH |
606 | |
607 | retval = blk_alloc_devt(&disk->part0, &devt); | |
608 | if (retval) { | |
609 | WARN_ON(1); | |
610 | return; | |
611 | } | |
612 | disk_to_dev(disk)->devt = devt; | |
613 | ||
614 | /* ->major and ->first_minor aren't supposed to be | |
615 | * dereferenced from here on, but set them just in case. | |
616 | */ | |
617 | disk->major = MAJOR(devt); | |
618 | disk->first_minor = MINOR(devt); | |
619 | ||
9f53d2fe SG |
620 | disk_alloc_events(disk); |
621 | ||
9f5e4865 | 622 | /* Register BDI before referencing it from bdev */ |
01ea5063 SJK |
623 | bdi = &disk->queue->backing_dev_info; |
624 | bdi_register_dev(bdi, disk_devt(disk)); | |
625 | ||
f331c029 TH |
626 | blk_register_region(disk_devt(disk), disk->minors, NULL, |
627 | exact_match, exact_lock, disk); | |
1da177e4 LT |
628 | register_disk(disk); |
629 | blk_register_queue(disk); | |
cf0ca9fe | 630 | |
523e1d39 TH |
631 | /* |
632 | * Take an extra ref on queue which will be put on disk_release() | |
633 | * so that it sticks around as long as @disk is there. | |
634 | */ | |
09ac46c4 | 635 | WARN_ON_ONCE(!blk_get_queue(disk->queue)); |
523e1d39 | 636 | |
ed9e1982 TH |
637 | retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj, |
638 | "bdi"); | |
6ffeea77 | 639 | WARN_ON(retval); |
1da177e4 | 640 | |
77ea887e | 641 | disk_add_events(disk); |
1da177e4 | 642 | } |
1da177e4 | 643 | EXPORT_SYMBOL(add_disk); |
1da177e4 | 644 | |
d2bf1b67 | 645 | void del_gendisk(struct gendisk *disk) |
1da177e4 | 646 | { |
d2bf1b67 TH |
647 | struct disk_part_iter piter; |
648 | struct hd_struct *part; | |
649 | ||
77ea887e TH |
650 | disk_del_events(disk); |
651 | ||
d2bf1b67 TH |
652 | /* invalidate stuff */ |
653 | disk_part_iter_init(&piter, disk, | |
654 | DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE); | |
655 | while ((part = disk_part_iter_next(&piter))) { | |
656 | invalidate_partition(disk, part->partno); | |
657 | delete_partition(disk, part->partno); | |
658 | } | |
659 | disk_part_iter_exit(&piter); | |
660 | ||
661 | invalidate_partition(disk, 0); | |
d2bf1b67 TH |
662 | set_capacity(disk, 0); |
663 | disk->flags &= ~GENHD_FL_UP; | |
664 | ||
ed9e1982 | 665 | sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi"); |
cf0ca9fe | 666 | bdi_unregister(&disk->queue->backing_dev_info); |
1da177e4 | 667 | blk_unregister_queue(disk); |
f331c029 | 668 | blk_unregister_region(disk_devt(disk), disk->minors); |
d2bf1b67 TH |
669 | |
670 | part_stat_set_all(&disk->part0, 0); | |
671 | disk->part0.stamp = 0; | |
672 | ||
673 | kobject_put(disk->part0.holder_dir); | |
674 | kobject_put(disk->slave_dir); | |
675 | disk->driverfs_dev = NULL; | |
676 | if (!sysfs_deprecated) | |
677 | sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); | |
25e823c8 | 678 | pm_runtime_set_memalloc_noio(disk_to_dev(disk), false); |
d2bf1b67 | 679 | device_del(disk_to_dev(disk)); |
7b74e912 | 680 | blk_free_devt(disk_to_dev(disk)->devt); |
1da177e4 | 681 | } |
d2bf1b67 | 682 | EXPORT_SYMBOL(del_gendisk); |
1da177e4 | 683 | |
1da177e4 LT |
684 | /** |
685 | * get_gendisk - get partitioning information for a given device | |
710027a4 | 686 | * @devt: device to get partitioning information for |
496aa8a9 | 687 | * @partno: returned partition index |
1da177e4 LT |
688 | * |
689 | * This function gets the structure containing partitioning | |
710027a4 | 690 | * information for the given device @devt. |
1da177e4 | 691 | */ |
cf771cb5 | 692 | struct gendisk *get_gendisk(dev_t devt, int *partno) |
1da177e4 | 693 | { |
bcce3de1 TH |
694 | struct gendisk *disk = NULL; |
695 | ||
696 | if (MAJOR(devt) != BLOCK_EXT_MAJOR) { | |
697 | struct kobject *kobj; | |
698 | ||
699 | kobj = kobj_lookup(bdev_map, devt, partno); | |
700 | if (kobj) | |
701 | disk = dev_to_disk(kobj_to_dev(kobj)); | |
702 | } else { | |
703 | struct hd_struct *part; | |
704 | ||
705 | mutex_lock(&ext_devt_mutex); | |
870d6656 | 706 | part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt))); |
bcce3de1 TH |
707 | if (part && get_disk(part_to_disk(part))) { |
708 | *partno = part->partno; | |
709 | disk = part_to_disk(part); | |
710 | } | |
711 | mutex_unlock(&ext_devt_mutex); | |
712 | } | |
edfaa7c3 | 713 | |
bcce3de1 | 714 | return disk; |
1da177e4 | 715 | } |
b6ac23af | 716 | EXPORT_SYMBOL(get_gendisk); |
1da177e4 | 717 | |
f331c029 TH |
718 | /** |
719 | * bdget_disk - do bdget() by gendisk and partition number | |
720 | * @disk: gendisk of interest | |
721 | * @partno: partition number | |
722 | * | |
723 | * Find partition @partno from @disk, do bdget() on it. | |
724 | * | |
725 | * CONTEXT: | |
726 | * Don't care. | |
727 | * | |
728 | * RETURNS: | |
729 | * Resulting block_device on success, NULL on failure. | |
730 | */ | |
aeb3d3a8 | 731 | struct block_device *bdget_disk(struct gendisk *disk, int partno) |
f331c029 | 732 | { |
548b10eb TH |
733 | struct hd_struct *part; |
734 | struct block_device *bdev = NULL; | |
f331c029 | 735 | |
548b10eb | 736 | part = disk_get_part(disk, partno); |
2bbedcb4 | 737 | if (part) |
548b10eb TH |
738 | bdev = bdget(part_devt(part)); |
739 | disk_put_part(part); | |
f331c029 | 740 | |
548b10eb | 741 | return bdev; |
f331c029 TH |
742 | } |
743 | EXPORT_SYMBOL(bdget_disk); | |
744 | ||
5c6f35c5 GKH |
745 | /* |
746 | * print a full list of all partitions - intended for places where the root | |
747 | * filesystem can't be mounted and thus to give the victim some idea of what | |
748 | * went wrong | |
749 | */ | |
750 | void __init printk_all_partitions(void) | |
751 | { | |
def4e38d TH |
752 | struct class_dev_iter iter; |
753 | struct device *dev; | |
754 | ||
755 | class_dev_iter_init(&iter, &block_class, NULL, &disk_type); | |
756 | while ((dev = class_dev_iter_next(&iter))) { | |
757 | struct gendisk *disk = dev_to_disk(dev); | |
e71bf0d0 TH |
758 | struct disk_part_iter piter; |
759 | struct hd_struct *part; | |
1f014290 TH |
760 | char name_buf[BDEVNAME_SIZE]; |
761 | char devt_buf[BDEVT_SIZE]; | |
def4e38d TH |
762 | |
763 | /* | |
764 | * Don't show empty devices or things that have been | |
25985edc | 765 | * suppressed |
def4e38d TH |
766 | */ |
767 | if (get_capacity(disk) == 0 || | |
768 | (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)) | |
769 | continue; | |
770 | ||
771 | /* | |
772 | * Note, unlike /proc/partitions, I am showing the | |
773 | * numbers in hex - the same format as the root= | |
774 | * option takes. | |
775 | */ | |
074a7aca TH |
776 | disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); |
777 | while ((part = disk_part_iter_next(&piter))) { | |
778 | bool is_part0 = part == &disk->part0; | |
def4e38d | 779 | |
b5af921e | 780 | printk("%s%s %10llu %s %s", is_part0 ? "" : " ", |
1f014290 | 781 | bdevt_str(part_devt(part), devt_buf), |
c83f6bf9 VG |
782 | (unsigned long long)part_nr_sects_read(part) >> 1 |
783 | , disk_name(disk, part->partno, name_buf), | |
1ad7e899 | 784 | part->info ? part->info->uuid : ""); |
074a7aca TH |
785 | if (is_part0) { |
786 | if (disk->driverfs_dev != NULL && | |
787 | disk->driverfs_dev->driver != NULL) | |
788 | printk(" driver: %s\n", | |
789 | disk->driverfs_dev->driver->name); | |
790 | else | |
791 | printk(" (driver?)\n"); | |
792 | } else | |
793 | printk("\n"); | |
794 | } | |
e71bf0d0 | 795 | disk_part_iter_exit(&piter); |
def4e38d TH |
796 | } |
797 | class_dev_iter_exit(&iter); | |
dd2a345f DG |
798 | } |
799 | ||
1da177e4 LT |
800 | #ifdef CONFIG_PROC_FS |
801 | /* iterator */ | |
def4e38d | 802 | static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos) |
68c4d4a7 | 803 | { |
def4e38d TH |
804 | loff_t skip = *pos; |
805 | struct class_dev_iter *iter; | |
806 | struct device *dev; | |
68c4d4a7 | 807 | |
aeb3d3a8 | 808 | iter = kmalloc(sizeof(*iter), GFP_KERNEL); |
def4e38d TH |
809 | if (!iter) |
810 | return ERR_PTR(-ENOMEM); | |
811 | ||
812 | seqf->private = iter; | |
813 | class_dev_iter_init(iter, &block_class, NULL, &disk_type); | |
814 | do { | |
815 | dev = class_dev_iter_next(iter); | |
816 | if (!dev) | |
817 | return NULL; | |
818 | } while (skip--); | |
819 | ||
820 | return dev_to_disk(dev); | |
68c4d4a7 GKH |
821 | } |
822 | ||
def4e38d | 823 | static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos) |
1da177e4 | 824 | { |
edfaa7c3 | 825 | struct device *dev; |
1da177e4 | 826 | |
def4e38d TH |
827 | (*pos)++; |
828 | dev = class_dev_iter_next(seqf->private); | |
2ac3cee5 | 829 | if (dev) |
68c4d4a7 | 830 | return dev_to_disk(dev); |
2ac3cee5 | 831 | |
1da177e4 LT |
832 | return NULL; |
833 | } | |
834 | ||
def4e38d | 835 | static void disk_seqf_stop(struct seq_file *seqf, void *v) |
27f30251 | 836 | { |
def4e38d | 837 | struct class_dev_iter *iter = seqf->private; |
27f30251 | 838 | |
def4e38d TH |
839 | /* stop is called even after start failed :-( */ |
840 | if (iter) { | |
841 | class_dev_iter_exit(iter); | |
842 | kfree(iter); | |
5c0ef6d0 | 843 | } |
1da177e4 LT |
844 | } |
845 | ||
def4e38d | 846 | static void *show_partition_start(struct seq_file *seqf, loff_t *pos) |
1da177e4 | 847 | { |
06768067 | 848 | void *p; |
def4e38d TH |
849 | |
850 | p = disk_seqf_start(seqf, pos); | |
b9f985b6 | 851 | if (!IS_ERR_OR_NULL(p) && !*pos) |
def4e38d TH |
852 | seq_puts(seqf, "major minor #blocks name\n\n"); |
853 | return p; | |
1da177e4 LT |
854 | } |
855 | ||
cf771cb5 | 856 | static int show_partition(struct seq_file *seqf, void *v) |
1da177e4 LT |
857 | { |
858 | struct gendisk *sgp = v; | |
e71bf0d0 TH |
859 | struct disk_part_iter piter; |
860 | struct hd_struct *part; | |
1da177e4 LT |
861 | char buf[BDEVNAME_SIZE]; |
862 | ||
1da177e4 | 863 | /* Don't show non-partitionable removeable devices or empty devices */ |
d27769ec | 864 | if (!get_capacity(sgp) || (!disk_max_parts(sgp) && |
f331c029 | 865 | (sgp->flags & GENHD_FL_REMOVABLE))) |
1da177e4 LT |
866 | return 0; |
867 | if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO) | |
868 | return 0; | |
869 | ||
870 | /* show the full disk and all non-0 size partitions of it */ | |
074a7aca | 871 | disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0); |
e71bf0d0 | 872 | while ((part = disk_part_iter_next(&piter))) |
1f014290 | 873 | seq_printf(seqf, "%4d %7d %10llu %s\n", |
f331c029 | 874 | MAJOR(part_devt(part)), MINOR(part_devt(part)), |
c83f6bf9 | 875 | (unsigned long long)part_nr_sects_read(part) >> 1, |
f331c029 | 876 | disk_name(sgp, part->partno, buf)); |
e71bf0d0 | 877 | disk_part_iter_exit(&piter); |
1da177e4 LT |
878 | |
879 | return 0; | |
880 | } | |
881 | ||
f500975a | 882 | static const struct seq_operations partitions_op = { |
def4e38d TH |
883 | .start = show_partition_start, |
884 | .next = disk_seqf_next, | |
885 | .stop = disk_seqf_stop, | |
edfaa7c3 | 886 | .show = show_partition |
1da177e4 | 887 | }; |
f500975a AD |
888 | |
889 | static int partitions_open(struct inode *inode, struct file *file) | |
890 | { | |
891 | return seq_open(file, &partitions_op); | |
892 | } | |
893 | ||
894 | static const struct file_operations proc_partitions_operations = { | |
895 | .open = partitions_open, | |
896 | .read = seq_read, | |
897 | .llseek = seq_lseek, | |
898 | .release = seq_release, | |
899 | }; | |
1da177e4 LT |
900 | #endif |
901 | ||
902 | ||
cf771cb5 | 903 | static struct kobject *base_probe(dev_t devt, int *partno, void *data) |
1da177e4 | 904 | { |
edfaa7c3 | 905 | if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0) |
1da177e4 | 906 | /* Make old-style 2.4 aliases work */ |
edfaa7c3 | 907 | request_module("block-major-%d", MAJOR(devt)); |
1da177e4 LT |
908 | return NULL; |
909 | } | |
910 | ||
911 | static int __init genhd_device_init(void) | |
912 | { | |
e105b8bf DW |
913 | int error; |
914 | ||
915 | block_class.dev_kobj = sysfs_dev_block_kobj; | |
916 | error = class_register(&block_class); | |
ee27a558 RM |
917 | if (unlikely(error)) |
918 | return error; | |
edfaa7c3 | 919 | bdev_map = kobj_map_init(base_probe, &block_class_lock); |
1da177e4 | 920 | blk_dev_init(); |
edfaa7c3 | 921 | |
561ec68e ZY |
922 | register_blkdev(BLOCK_EXT_MAJOR, "blkext"); |
923 | ||
edfaa7c3 | 924 | /* create top-level block dir */ |
e52eec13 AK |
925 | if (!sysfs_deprecated) |
926 | block_depr = kobject_create_and_add("block", NULL); | |
830d3cfb | 927 | return 0; |
1da177e4 LT |
928 | } |
929 | ||
930 | subsys_initcall(genhd_device_init); | |
931 | ||
edfaa7c3 KS |
932 | static ssize_t disk_range_show(struct device *dev, |
933 | struct device_attribute *attr, char *buf) | |
1da177e4 | 934 | { |
edfaa7c3 | 935 | struct gendisk *disk = dev_to_disk(dev); |
1da177e4 | 936 | |
edfaa7c3 | 937 | return sprintf(buf, "%d\n", disk->minors); |
1da177e4 LT |
938 | } |
939 | ||
1f014290 TH |
940 | static ssize_t disk_ext_range_show(struct device *dev, |
941 | struct device_attribute *attr, char *buf) | |
942 | { | |
943 | struct gendisk *disk = dev_to_disk(dev); | |
944 | ||
b5d0b9df | 945 | return sprintf(buf, "%d\n", disk_max_parts(disk)); |
1f014290 TH |
946 | } |
947 | ||
edfaa7c3 KS |
948 | static ssize_t disk_removable_show(struct device *dev, |
949 | struct device_attribute *attr, char *buf) | |
a7fd6706 | 950 | { |
edfaa7c3 | 951 | struct gendisk *disk = dev_to_disk(dev); |
a7fd6706 | 952 | |
edfaa7c3 KS |
953 | return sprintf(buf, "%d\n", |
954 | (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0)); | |
a7fd6706 KS |
955 | } |
956 | ||
1c9ce527 KS |
957 | static ssize_t disk_ro_show(struct device *dev, |
958 | struct device_attribute *attr, char *buf) | |
959 | { | |
960 | struct gendisk *disk = dev_to_disk(dev); | |
961 | ||
b7db9956 | 962 | return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0); |
1c9ce527 KS |
963 | } |
964 | ||
edfaa7c3 KS |
965 | static ssize_t disk_capability_show(struct device *dev, |
966 | struct device_attribute *attr, char *buf) | |
86ce18d7 | 967 | { |
edfaa7c3 KS |
968 | struct gendisk *disk = dev_to_disk(dev); |
969 | ||
970 | return sprintf(buf, "%x\n", disk->flags); | |
86ce18d7 | 971 | } |
edfaa7c3 | 972 | |
c72758f3 MP |
973 | static ssize_t disk_alignment_offset_show(struct device *dev, |
974 | struct device_attribute *attr, | |
975 | char *buf) | |
976 | { | |
977 | struct gendisk *disk = dev_to_disk(dev); | |
978 | ||
979 | return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue)); | |
980 | } | |
981 | ||
86b37281 MP |
982 | static ssize_t disk_discard_alignment_show(struct device *dev, |
983 | struct device_attribute *attr, | |
984 | char *buf) | |
985 | { | |
986 | struct gendisk *disk = dev_to_disk(dev); | |
987 | ||
dd3d145d | 988 | return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue)); |
86b37281 MP |
989 | } |
990 | ||
edfaa7c3 | 991 | static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL); |
1f014290 | 992 | static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL); |
edfaa7c3 | 993 | static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL); |
1c9ce527 | 994 | static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL); |
e5610521 | 995 | static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL); |
c72758f3 | 996 | static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL); |
86b37281 MP |
997 | static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show, |
998 | NULL); | |
edfaa7c3 | 999 | static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL); |
074a7aca | 1000 | static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); |
316d315b | 1001 | static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); |
c17bb495 | 1002 | #ifdef CONFIG_FAIL_MAKE_REQUEST |
edfaa7c3 | 1003 | static struct device_attribute dev_attr_fail = |
eddb2e26 | 1004 | __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store); |
c17bb495 | 1005 | #endif |
581d4e28 JA |
1006 | #ifdef CONFIG_FAIL_IO_TIMEOUT |
1007 | static struct device_attribute dev_attr_fail_timeout = | |
1008 | __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show, | |
1009 | part_timeout_store); | |
1010 | #endif | |
edfaa7c3 KS |
1011 | |
1012 | static struct attribute *disk_attrs[] = { | |
1013 | &dev_attr_range.attr, | |
1f014290 | 1014 | &dev_attr_ext_range.attr, |
edfaa7c3 | 1015 | &dev_attr_removable.attr, |
1c9ce527 | 1016 | &dev_attr_ro.attr, |
edfaa7c3 | 1017 | &dev_attr_size.attr, |
c72758f3 | 1018 | &dev_attr_alignment_offset.attr, |
86b37281 | 1019 | &dev_attr_discard_alignment.attr, |
edfaa7c3 KS |
1020 | &dev_attr_capability.attr, |
1021 | &dev_attr_stat.attr, | |
316d315b | 1022 | &dev_attr_inflight.attr, |
edfaa7c3 KS |
1023 | #ifdef CONFIG_FAIL_MAKE_REQUEST |
1024 | &dev_attr_fail.attr, | |
581d4e28 JA |
1025 | #endif |
1026 | #ifdef CONFIG_FAIL_IO_TIMEOUT | |
1027 | &dev_attr_fail_timeout.attr, | |
edfaa7c3 KS |
1028 | #endif |
1029 | NULL | |
1030 | }; | |
1031 | ||
1032 | static struct attribute_group disk_attr_group = { | |
1033 | .attrs = disk_attrs, | |
1034 | }; | |
1035 | ||
a4dbd674 | 1036 | static const struct attribute_group *disk_attr_groups[] = { |
edfaa7c3 KS |
1037 | &disk_attr_group, |
1038 | NULL | |
1da177e4 LT |
1039 | }; |
1040 | ||
540eed56 TH |
1041 | /** |
1042 | * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way | |
1043 | * @disk: disk to replace part_tbl for | |
1044 | * @new_ptbl: new part_tbl to install | |
1045 | * | |
1046 | * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The | |
1047 | * original ptbl is freed using RCU callback. | |
1048 | * | |
1049 | * LOCKING: | |
1050 | * Matching bd_mutx locked. | |
1051 | */ | |
1052 | static void disk_replace_part_tbl(struct gendisk *disk, | |
1053 | struct disk_part_tbl *new_ptbl) | |
1054 | { | |
1055 | struct disk_part_tbl *old_ptbl = disk->part_tbl; | |
1056 | ||
1057 | rcu_assign_pointer(disk->part_tbl, new_ptbl); | |
a6f23657 JA |
1058 | |
1059 | if (old_ptbl) { | |
1060 | rcu_assign_pointer(old_ptbl->last_lookup, NULL); | |
57bdfbf9 | 1061 | kfree_rcu(old_ptbl, rcu_head); |
a6f23657 | 1062 | } |
540eed56 TH |
1063 | } |
1064 | ||
1065 | /** | |
1066 | * disk_expand_part_tbl - expand disk->part_tbl | |
1067 | * @disk: disk to expand part_tbl for | |
1068 | * @partno: expand such that this partno can fit in | |
1069 | * | |
1070 | * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl | |
1071 | * uses RCU to allow unlocked dereferencing for stats and other stuff. | |
1072 | * | |
1073 | * LOCKING: | |
1074 | * Matching bd_mutex locked, might sleep. | |
1075 | * | |
1076 | * RETURNS: | |
1077 | * 0 on success, -errno on failure. | |
1078 | */ | |
1079 | int disk_expand_part_tbl(struct gendisk *disk, int partno) | |
1080 | { | |
1081 | struct disk_part_tbl *old_ptbl = disk->part_tbl; | |
1082 | struct disk_part_tbl *new_ptbl; | |
1083 | int len = old_ptbl ? old_ptbl->len : 0; | |
1084 | int target = partno + 1; | |
1085 | size_t size; | |
1086 | int i; | |
1087 | ||
1088 | /* disk_max_parts() is zero during initialization, ignore if so */ | |
1089 | if (disk_max_parts(disk) && target > disk_max_parts(disk)) | |
1090 | return -EINVAL; | |
1091 | ||
1092 | if (target <= len) | |
1093 | return 0; | |
1094 | ||
1095 | size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]); | |
1096 | new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id); | |
1097 | if (!new_ptbl) | |
1098 | return -ENOMEM; | |
1099 | ||
540eed56 TH |
1100 | new_ptbl->len = target; |
1101 | ||
1102 | for (i = 0; i < len; i++) | |
1103 | rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]); | |
1104 | ||
1105 | disk_replace_part_tbl(disk, new_ptbl); | |
1106 | return 0; | |
1107 | } | |
1108 | ||
edfaa7c3 | 1109 | static void disk_release(struct device *dev) |
1da177e4 | 1110 | { |
edfaa7c3 KS |
1111 | struct gendisk *disk = dev_to_disk(dev); |
1112 | ||
77ea887e | 1113 | disk_release_events(disk); |
1da177e4 | 1114 | kfree(disk->random); |
540eed56 | 1115 | disk_replace_part_tbl(disk, NULL); |
074a7aca | 1116 | free_part_stats(&disk->part0); |
6d1d8050 | 1117 | free_part_info(&disk->part0); |
523e1d39 TH |
1118 | if (disk->queue) |
1119 | blk_put_queue(disk->queue); | |
1da177e4 LT |
1120 | kfree(disk); |
1121 | } | |
edfaa7c3 KS |
1122 | struct class block_class = { |
1123 | .name = "block", | |
1da177e4 LT |
1124 | }; |
1125 | ||
2c9ede55 | 1126 | static char *block_devnode(struct device *dev, umode_t *mode) |
b03f38b6 KS |
1127 | { |
1128 | struct gendisk *disk = dev_to_disk(dev); | |
1129 | ||
e454cea2 KS |
1130 | if (disk->devnode) |
1131 | return disk->devnode(disk, mode); | |
b03f38b6 KS |
1132 | return NULL; |
1133 | } | |
1134 | ||
1826eadf | 1135 | static struct device_type disk_type = { |
edfaa7c3 KS |
1136 | .name = "disk", |
1137 | .groups = disk_attr_groups, | |
1138 | .release = disk_release, | |
e454cea2 | 1139 | .devnode = block_devnode, |
1da177e4 LT |
1140 | }; |
1141 | ||
a6e2ba88 | 1142 | #ifdef CONFIG_PROC_FS |
cf771cb5 TH |
1143 | /* |
1144 | * aggregate disk stat collector. Uses the same stats that the sysfs | |
1145 | * entries do, above, but makes them available through one seq_file. | |
1146 | * | |
1147 | * The output looks suspiciously like /proc/partitions with a bunch of | |
1148 | * extra fields. | |
1149 | */ | |
1150 | static int diskstats_show(struct seq_file *seqf, void *v) | |
1da177e4 LT |
1151 | { |
1152 | struct gendisk *gp = v; | |
e71bf0d0 TH |
1153 | struct disk_part_iter piter; |
1154 | struct hd_struct *hd; | |
1da177e4 | 1155 | char buf[BDEVNAME_SIZE]; |
c9959059 | 1156 | int cpu; |
1da177e4 LT |
1157 | |
1158 | /* | |
ed9e1982 | 1159 | if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next) |
cf771cb5 | 1160 | seq_puts(seqf, "major minor name" |
1da177e4 LT |
1161 | " rio rmerge rsect ruse wio wmerge " |
1162 | "wsect wuse running use aveq" | |
1163 | "\n\n"); | |
1164 | */ | |
9f5e4865 | 1165 | |
71982a40 | 1166 | disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0); |
e71bf0d0 | 1167 | while ((hd = disk_part_iter_next(&piter))) { |
074a7aca | 1168 | cpu = part_stat_lock(); |
c9959059 | 1169 | part_round_stats(cpu, hd); |
074a7aca | 1170 | part_stat_unlock(); |
f95fe9cf HP |
1171 | seq_printf(seqf, "%4d %7d %s %lu %lu %lu " |
1172 | "%u %lu %lu %lu %u %u %u %u\n", | |
f331c029 TH |
1173 | MAJOR(part_devt(hd)), MINOR(part_devt(hd)), |
1174 | disk_name(gp, hd->partno, buf), | |
53f22956 LY |
1175 | part_stat_read(hd, ios[READ]), |
1176 | part_stat_read(hd, merges[READ]), | |
f95fe9cf | 1177 | part_stat_read(hd, sectors[READ]), |
53f22956 LY |
1178 | jiffies_to_msecs(part_stat_read(hd, ticks[READ])), |
1179 | part_stat_read(hd, ios[WRITE]), | |
1180 | part_stat_read(hd, merges[WRITE]), | |
f95fe9cf | 1181 | part_stat_read(hd, sectors[WRITE]), |
53f22956 | 1182 | jiffies_to_msecs(part_stat_read(hd, ticks[WRITE])), |
316d315b | 1183 | part_in_flight(hd), |
28f39d55 JM |
1184 | jiffies_to_msecs(part_stat_read(hd, io_ticks)), |
1185 | jiffies_to_msecs(part_stat_read(hd, time_in_queue)) | |
1186 | ); | |
1da177e4 | 1187 | } |
e71bf0d0 | 1188 | disk_part_iter_exit(&piter); |
9f5e4865 | 1189 | |
1da177e4 LT |
1190 | return 0; |
1191 | } | |
1192 | ||
31d85ab2 | 1193 | static const struct seq_operations diskstats_op = { |
def4e38d TH |
1194 | .start = disk_seqf_start, |
1195 | .next = disk_seqf_next, | |
1196 | .stop = disk_seqf_stop, | |
1da177e4 LT |
1197 | .show = diskstats_show |
1198 | }; | |
f500975a | 1199 | |
31d85ab2 AD |
1200 | static int diskstats_open(struct inode *inode, struct file *file) |
1201 | { | |
1202 | return seq_open(file, &diskstats_op); | |
1203 | } | |
1204 | ||
1205 | static const struct file_operations proc_diskstats_operations = { | |
1206 | .open = diskstats_open, | |
1207 | .read = seq_read, | |
1208 | .llseek = seq_lseek, | |
1209 | .release = seq_release, | |
1210 | }; | |
1211 | ||
f500975a AD |
1212 | static int __init proc_genhd_init(void) |
1213 | { | |
31d85ab2 | 1214 | proc_create("diskstats", 0, NULL, &proc_diskstats_operations); |
f500975a AD |
1215 | proc_create("partitions", 0, NULL, &proc_partitions_operations); |
1216 | return 0; | |
1217 | } | |
1218 | module_init(proc_genhd_init); | |
a6e2ba88 | 1219 | #endif /* CONFIG_PROC_FS */ |
1da177e4 | 1220 | |
cf771cb5 | 1221 | dev_t blk_lookup_devt(const char *name, int partno) |
a142be85 | 1222 | { |
def4e38d TH |
1223 | dev_t devt = MKDEV(0, 0); |
1224 | struct class_dev_iter iter; | |
1225 | struct device *dev; | |
a142be85 | 1226 | |
def4e38d TH |
1227 | class_dev_iter_init(&iter, &block_class, NULL, &disk_type); |
1228 | while ((dev = class_dev_iter_next(&iter))) { | |
a142be85 | 1229 | struct gendisk *disk = dev_to_disk(dev); |
548b10eb | 1230 | struct hd_struct *part; |
a142be85 | 1231 | |
3ada8b7e | 1232 | if (strcmp(dev_name(dev), name)) |
f331c029 | 1233 | continue; |
f331c029 | 1234 | |
41b8c853 NB |
1235 | if (partno < disk->minors) { |
1236 | /* We need to return the right devno, even | |
1237 | * if the partition doesn't exist yet. | |
1238 | */ | |
1239 | devt = MKDEV(MAJOR(dev->devt), | |
1240 | MINOR(dev->devt) + partno); | |
1241 | break; | |
1242 | } | |
548b10eb | 1243 | part = disk_get_part(disk, partno); |
2bbedcb4 | 1244 | if (part) { |
f331c029 | 1245 | devt = part_devt(part); |
e71bf0d0 | 1246 | disk_put_part(part); |
548b10eb | 1247 | break; |
def4e38d | 1248 | } |
548b10eb | 1249 | disk_put_part(part); |
5c0ef6d0 | 1250 | } |
def4e38d | 1251 | class_dev_iter_exit(&iter); |
edfaa7c3 KS |
1252 | return devt; |
1253 | } | |
edfaa7c3 KS |
1254 | EXPORT_SYMBOL(blk_lookup_devt); |
1255 | ||
1da177e4 LT |
1256 | struct gendisk *alloc_disk(int minors) |
1257 | { | |
c304a51b | 1258 | return alloc_disk_node(minors, NUMA_NO_NODE); |
1946089a | 1259 | } |
689d6fac | 1260 | EXPORT_SYMBOL(alloc_disk); |
1946089a CL |
1261 | |
1262 | struct gendisk *alloc_disk_node(int minors, int node_id) | |
1263 | { | |
1264 | struct gendisk *disk; | |
1265 | ||
94f6030c CL |
1266 | disk = kmalloc_node(sizeof(struct gendisk), |
1267 | GFP_KERNEL | __GFP_ZERO, node_id); | |
1da177e4 | 1268 | if (disk) { |
074a7aca | 1269 | if (!init_part_stats(&disk->part0)) { |
1da177e4 LT |
1270 | kfree(disk); |
1271 | return NULL; | |
1272 | } | |
bf91db18 | 1273 | disk->node_id = node_id; |
540eed56 TH |
1274 | if (disk_expand_part_tbl(disk, 0)) { |
1275 | free_part_stats(&disk->part0); | |
b5d0b9df TH |
1276 | kfree(disk); |
1277 | return NULL; | |
1da177e4 | 1278 | } |
540eed56 | 1279 | disk->part_tbl->part[0] = &disk->part0; |
6c23a968 | 1280 | |
c83f6bf9 VG |
1281 | /* |
1282 | * set_capacity() and get_capacity() currently don't use | |
1283 | * seqcounter to read/update the part0->nr_sects. Still init | |
1284 | * the counter as we can read the sectors in IO submission | |
1285 | * patch using seqence counters. | |
1286 | * | |
1287 | * TODO: Ideally set_capacity() and get_capacity() should be | |
1288 | * converted to make use of bd_mutex and sequence counters. | |
1289 | */ | |
1290 | seqcount_init(&disk->part0.nr_sects_seq); | |
6c23a968 | 1291 | hd_ref_init(&disk->part0); |
b5d0b9df | 1292 | |
1da177e4 | 1293 | disk->minors = minors; |
1da177e4 | 1294 | rand_initialize_disk(disk); |
ed9e1982 TH |
1295 | disk_to_dev(disk)->class = &block_class; |
1296 | disk_to_dev(disk)->type = &disk_type; | |
1297 | device_initialize(disk_to_dev(disk)); | |
1da177e4 LT |
1298 | } |
1299 | return disk; | |
1300 | } | |
1946089a | 1301 | EXPORT_SYMBOL(alloc_disk_node); |
1da177e4 LT |
1302 | |
1303 | struct kobject *get_disk(struct gendisk *disk) | |
1304 | { | |
1305 | struct module *owner; | |
1306 | struct kobject *kobj; | |
1307 | ||
1308 | if (!disk->fops) | |
1309 | return NULL; | |
1310 | owner = disk->fops->owner; | |
1311 | if (owner && !try_module_get(owner)) | |
1312 | return NULL; | |
ed9e1982 | 1313 | kobj = kobject_get(&disk_to_dev(disk)->kobj); |
1da177e4 LT |
1314 | if (kobj == NULL) { |
1315 | module_put(owner); | |
1316 | return NULL; | |
1317 | } | |
1318 | return kobj; | |
1319 | ||
1320 | } | |
1321 | ||
1322 | EXPORT_SYMBOL(get_disk); | |
1323 | ||
1324 | void put_disk(struct gendisk *disk) | |
1325 | { | |
1326 | if (disk) | |
ed9e1982 | 1327 | kobject_put(&disk_to_dev(disk)->kobj); |
1da177e4 LT |
1328 | } |
1329 | ||
1330 | EXPORT_SYMBOL(put_disk); | |
1331 | ||
e3264a4d HR |
1332 | static void set_disk_ro_uevent(struct gendisk *gd, int ro) |
1333 | { | |
1334 | char event[] = "DISK_RO=1"; | |
1335 | char *envp[] = { event, NULL }; | |
1336 | ||
1337 | if (!ro) | |
1338 | event[8] = '0'; | |
1339 | kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp); | |
1340 | } | |
1341 | ||
1da177e4 LT |
1342 | void set_device_ro(struct block_device *bdev, int flag) |
1343 | { | |
b7db9956 | 1344 | bdev->bd_part->policy = flag; |
1da177e4 LT |
1345 | } |
1346 | ||
1347 | EXPORT_SYMBOL(set_device_ro); | |
1348 | ||
1349 | void set_disk_ro(struct gendisk *disk, int flag) | |
1350 | { | |
e71bf0d0 TH |
1351 | struct disk_part_iter piter; |
1352 | struct hd_struct *part; | |
1353 | ||
e3264a4d HR |
1354 | if (disk->part0.policy != flag) { |
1355 | set_disk_ro_uevent(disk, flag); | |
1356 | disk->part0.policy = flag; | |
1357 | } | |
1358 | ||
1359 | disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); | |
e71bf0d0 TH |
1360 | while ((part = disk_part_iter_next(&piter))) |
1361 | part->policy = flag; | |
1362 | disk_part_iter_exit(&piter); | |
1da177e4 LT |
1363 | } |
1364 | ||
1365 | EXPORT_SYMBOL(set_disk_ro); | |
1366 | ||
1367 | int bdev_read_only(struct block_device *bdev) | |
1368 | { | |
1369 | if (!bdev) | |
1370 | return 0; | |
b7db9956 | 1371 | return bdev->bd_part->policy; |
1da177e4 LT |
1372 | } |
1373 | ||
1374 | EXPORT_SYMBOL(bdev_read_only); | |
1375 | ||
cf771cb5 | 1376 | int invalidate_partition(struct gendisk *disk, int partno) |
1da177e4 LT |
1377 | { |
1378 | int res = 0; | |
cf771cb5 | 1379 | struct block_device *bdev = bdget_disk(disk, partno); |
1da177e4 | 1380 | if (bdev) { |
2ef41634 | 1381 | fsync_bdev(bdev); |
93b270f7 | 1382 | res = __invalidate_device(bdev, true); |
1da177e4 LT |
1383 | bdput(bdev); |
1384 | } | |
1385 | return res; | |
1386 | } | |
1387 | ||
1388 | EXPORT_SYMBOL(invalidate_partition); | |
77ea887e TH |
1389 | |
1390 | /* | |
1391 | * Disk events - monitor disk events like media change and eject request. | |
1392 | */ | |
1393 | struct disk_events { | |
1394 | struct list_head node; /* all disk_event's */ | |
1395 | struct gendisk *disk; /* the associated disk */ | |
1396 | spinlock_t lock; | |
1397 | ||
fdd514e1 | 1398 | struct mutex block_mutex; /* protects blocking */ |
77ea887e TH |
1399 | int block; /* event blocking depth */ |
1400 | unsigned int pending; /* events already sent out */ | |
1401 | unsigned int clearing; /* events being cleared */ | |
1402 | ||
1403 | long poll_msecs; /* interval, -1 for default */ | |
1404 | struct delayed_work dwork; | |
1405 | }; | |
1406 | ||
1407 | static const char *disk_events_strs[] = { | |
1408 | [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "media_change", | |
1409 | [ilog2(DISK_EVENT_EJECT_REQUEST)] = "eject_request", | |
1410 | }; | |
1411 | ||
1412 | static char *disk_uevents[] = { | |
1413 | [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "DISK_MEDIA_CHANGE=1", | |
1414 | [ilog2(DISK_EVENT_EJECT_REQUEST)] = "DISK_EJECT_REQUEST=1", | |
1415 | }; | |
1416 | ||
1417 | /* list of all disk_events */ | |
1418 | static DEFINE_MUTEX(disk_events_mutex); | |
1419 | static LIST_HEAD(disk_events); | |
1420 | ||
1421 | /* disable in-kernel polling by default */ | |
1422 | static unsigned long disk_events_dfl_poll_msecs = 0; | |
1423 | ||
1424 | static unsigned long disk_events_poll_jiffies(struct gendisk *disk) | |
1425 | { | |
1426 | struct disk_events *ev = disk->ev; | |
1427 | long intv_msecs = 0; | |
1428 | ||
1429 | /* | |
1430 | * If device-specific poll interval is set, always use it. If | |
1431 | * the default is being used, poll iff there are events which | |
1432 | * can't be monitored asynchronously. | |
1433 | */ | |
1434 | if (ev->poll_msecs >= 0) | |
1435 | intv_msecs = ev->poll_msecs; | |
1436 | else if (disk->events & ~disk->async_events) | |
1437 | intv_msecs = disk_events_dfl_poll_msecs; | |
1438 | ||
1439 | return msecs_to_jiffies(intv_msecs); | |
1440 | } | |
1441 | ||
c3af54af TH |
1442 | /** |
1443 | * disk_block_events - block and flush disk event checking | |
1444 | * @disk: disk to block events for | |
1445 | * | |
1446 | * On return from this function, it is guaranteed that event checking | |
1447 | * isn't in progress and won't happen until unblocked by | |
1448 | * disk_unblock_events(). Events blocking is counted and the actual | |
1449 | * unblocking happens after the matching number of unblocks are done. | |
1450 | * | |
1451 | * Note that this intentionally does not block event checking from | |
1452 | * disk_clear_events(). | |
1453 | * | |
1454 | * CONTEXT: | |
1455 | * Might sleep. | |
1456 | */ | |
1457 | void disk_block_events(struct gendisk *disk) | |
77ea887e TH |
1458 | { |
1459 | struct disk_events *ev = disk->ev; | |
1460 | unsigned long flags; | |
1461 | bool cancel; | |
1462 | ||
c3af54af TH |
1463 | if (!ev) |
1464 | return; | |
1465 | ||
fdd514e1 TH |
1466 | /* |
1467 | * Outer mutex ensures that the first blocker completes canceling | |
1468 | * the event work before further blockers are allowed to finish. | |
1469 | */ | |
1470 | mutex_lock(&ev->block_mutex); | |
1471 | ||
77ea887e TH |
1472 | spin_lock_irqsave(&ev->lock, flags); |
1473 | cancel = !ev->block++; | |
1474 | spin_unlock_irqrestore(&ev->lock, flags); | |
1475 | ||
c3af54af TH |
1476 | if (cancel) |
1477 | cancel_delayed_work_sync(&disk->ev->dwork); | |
fdd514e1 TH |
1478 | |
1479 | mutex_unlock(&ev->block_mutex); | |
77ea887e TH |
1480 | } |
1481 | ||
1482 | static void __disk_unblock_events(struct gendisk *disk, bool check_now) | |
1483 | { | |
1484 | struct disk_events *ev = disk->ev; | |
1485 | unsigned long intv; | |
1486 | unsigned long flags; | |
1487 | ||
1488 | spin_lock_irqsave(&ev->lock, flags); | |
1489 | ||
1490 | if (WARN_ON_ONCE(ev->block <= 0)) | |
1491 | goto out_unlock; | |
1492 | ||
1493 | if (--ev->block) | |
1494 | goto out_unlock; | |
1495 | ||
1496 | /* | |
1497 | * Not exactly a latency critical operation, set poll timer | |
1498 | * slack to 25% and kick event check. | |
1499 | */ | |
1500 | intv = disk_events_poll_jiffies(disk); | |
1501 | set_timer_slack(&ev->dwork.timer, intv / 4); | |
1502 | if (check_now) | |
3b07e9ca | 1503 | queue_delayed_work(system_freezable_wq, &ev->dwork, 0); |
77ea887e | 1504 | else if (intv) |
3b07e9ca | 1505 | queue_delayed_work(system_freezable_wq, &ev->dwork, intv); |
77ea887e TH |
1506 | out_unlock: |
1507 | spin_unlock_irqrestore(&ev->lock, flags); | |
1508 | } | |
1509 | ||
77ea887e TH |
1510 | /** |
1511 | * disk_unblock_events - unblock disk event checking | |
1512 | * @disk: disk to unblock events for | |
1513 | * | |
1514 | * Undo disk_block_events(). When the block count reaches zero, it | |
1515 | * starts events polling if configured. | |
1516 | * | |
1517 | * CONTEXT: | |
1518 | * Don't care. Safe to call from irq context. | |
1519 | */ | |
1520 | void disk_unblock_events(struct gendisk *disk) | |
1521 | { | |
1522 | if (disk->ev) | |
facc31dd | 1523 | __disk_unblock_events(disk, false); |
77ea887e TH |
1524 | } |
1525 | ||
1526 | /** | |
85ef06d1 TH |
1527 | * disk_flush_events - schedule immediate event checking and flushing |
1528 | * @disk: disk to check and flush events for | |
1529 | * @mask: events to flush | |
77ea887e | 1530 | * |
85ef06d1 TH |
1531 | * Schedule immediate event checking on @disk if not blocked. Events in |
1532 | * @mask are scheduled to be cleared from the driver. Note that this | |
1533 | * doesn't clear the events from @disk->ev. | |
77ea887e TH |
1534 | * |
1535 | * CONTEXT: | |
85ef06d1 | 1536 | * If @mask is non-zero must be called with bdev->bd_mutex held. |
77ea887e | 1537 | */ |
85ef06d1 | 1538 | void disk_flush_events(struct gendisk *disk, unsigned int mask) |
77ea887e | 1539 | { |
a9dce2a3 | 1540 | struct disk_events *ev = disk->ev; |
a9dce2a3 TH |
1541 | |
1542 | if (!ev) | |
1543 | return; | |
1544 | ||
85ef06d1 TH |
1545 | spin_lock_irq(&ev->lock); |
1546 | ev->clearing |= mask; | |
41f63c53 | 1547 | if (!ev->block) |
3b07e9ca | 1548 | mod_delayed_work(system_freezable_wq, &ev->dwork, 0); |
85ef06d1 | 1549 | spin_unlock_irq(&ev->lock); |
77ea887e | 1550 | } |
77ea887e TH |
1551 | |
1552 | /** | |
1553 | * disk_clear_events - synchronously check, clear and return pending events | |
1554 | * @disk: disk to fetch and clear events from | |
1555 | * @mask: mask of events to be fetched and clearted | |
1556 | * | |
1557 | * Disk events are synchronously checked and pending events in @mask | |
1558 | * are cleared and returned. This ignores the block count. | |
1559 | * | |
1560 | * CONTEXT: | |
1561 | * Might sleep. | |
1562 | */ | |
1563 | unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask) | |
1564 | { | |
1565 | const struct block_device_operations *bdops = disk->fops; | |
1566 | struct disk_events *ev = disk->ev; | |
1567 | unsigned int pending; | |
12c2bdb2 | 1568 | unsigned int clearing = mask; |
77ea887e TH |
1569 | |
1570 | if (!ev) { | |
1571 | /* for drivers still using the old ->media_changed method */ | |
1572 | if ((mask & DISK_EVENT_MEDIA_CHANGE) && | |
1573 | bdops->media_changed && bdops->media_changed(disk)) | |
1574 | return DISK_EVENT_MEDIA_CHANGE; | |
1575 | return 0; | |
1576 | } | |
1577 | ||
12c2bdb2 DB |
1578 | disk_block_events(disk); |
1579 | ||
1580 | /* | |
1581 | * store the union of mask and ev->clearing on the stack so that the | |
1582 | * race with disk_flush_events does not cause ambiguity (ev->clearing | |
1583 | * can still be modified even if events are blocked). | |
1584 | */ | |
77ea887e | 1585 | spin_lock_irq(&ev->lock); |
12c2bdb2 DB |
1586 | clearing |= ev->clearing; |
1587 | ev->clearing = 0; | |
77ea887e TH |
1588 | spin_unlock_irq(&ev->lock); |
1589 | ||
12c2bdb2 | 1590 | disk_check_events(ev, &clearing); |
aea24a8b | 1591 | /* |
12c2bdb2 DB |
1592 | * if ev->clearing is not 0, the disk_flush_events got called in the |
1593 | * middle of this function, so we want to run the workfn without delay. | |
aea24a8b | 1594 | */ |
12c2bdb2 | 1595 | __disk_unblock_events(disk, ev->clearing ? true : false); |
77ea887e TH |
1596 | |
1597 | /* then, fetch and clear pending events */ | |
1598 | spin_lock_irq(&ev->lock); | |
77ea887e TH |
1599 | pending = ev->pending & mask; |
1600 | ev->pending &= ~mask; | |
1601 | spin_unlock_irq(&ev->lock); | |
12c2bdb2 | 1602 | WARN_ON_ONCE(clearing & mask); |
77ea887e TH |
1603 | |
1604 | return pending; | |
1605 | } | |
1606 | ||
12c2bdb2 DB |
1607 | /* |
1608 | * Separate this part out so that a different pointer for clearing_ptr can be | |
1609 | * passed in for disk_clear_events. | |
1610 | */ | |
77ea887e TH |
1611 | static void disk_events_workfn(struct work_struct *work) |
1612 | { | |
1613 | struct delayed_work *dwork = to_delayed_work(work); | |
1614 | struct disk_events *ev = container_of(dwork, struct disk_events, dwork); | |
12c2bdb2 DB |
1615 | |
1616 | disk_check_events(ev, &ev->clearing); | |
1617 | } | |
1618 | ||
1619 | static void disk_check_events(struct disk_events *ev, | |
1620 | unsigned int *clearing_ptr) | |
1621 | { | |
77ea887e TH |
1622 | struct gendisk *disk = ev->disk; |
1623 | char *envp[ARRAY_SIZE(disk_uevents) + 1] = { }; | |
12c2bdb2 | 1624 | unsigned int clearing = *clearing_ptr; |
77ea887e TH |
1625 | unsigned int events; |
1626 | unsigned long intv; | |
1627 | int nr_events = 0, i; | |
1628 | ||
1629 | /* check events */ | |
1630 | events = disk->fops->check_events(disk, clearing); | |
1631 | ||
1632 | /* accumulate pending events and schedule next poll if necessary */ | |
1633 | spin_lock_irq(&ev->lock); | |
1634 | ||
1635 | events &= ~ev->pending; | |
1636 | ev->pending |= events; | |
12c2bdb2 | 1637 | *clearing_ptr &= ~clearing; |
77ea887e TH |
1638 | |
1639 | intv = disk_events_poll_jiffies(disk); | |
1640 | if (!ev->block && intv) | |
3b07e9ca | 1641 | queue_delayed_work(system_freezable_wq, &ev->dwork, intv); |
77ea887e TH |
1642 | |
1643 | spin_unlock_irq(&ev->lock); | |
1644 | ||
7c88a168 TH |
1645 | /* |
1646 | * Tell userland about new events. Only the events listed in | |
1647 | * @disk->events are reported. Unlisted events are processed the | |
1648 | * same internally but never get reported to userland. | |
1649 | */ | |
77ea887e | 1650 | for (i = 0; i < ARRAY_SIZE(disk_uevents); i++) |
7c88a168 | 1651 | if (events & disk->events & (1 << i)) |
77ea887e TH |
1652 | envp[nr_events++] = disk_uevents[i]; |
1653 | ||
1654 | if (nr_events) | |
1655 | kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp); | |
1656 | } | |
1657 | ||
1658 | /* | |
1659 | * A disk events enabled device has the following sysfs nodes under | |
1660 | * its /sys/block/X/ directory. | |
1661 | * | |
1662 | * events : list of all supported events | |
1663 | * events_async : list of events which can be detected w/o polling | |
1664 | * events_poll_msecs : polling interval, 0: disable, -1: system default | |
1665 | */ | |
1666 | static ssize_t __disk_events_show(unsigned int events, char *buf) | |
1667 | { | |
1668 | const char *delim = ""; | |
1669 | ssize_t pos = 0; | |
1670 | int i; | |
1671 | ||
1672 | for (i = 0; i < ARRAY_SIZE(disk_events_strs); i++) | |
1673 | if (events & (1 << i)) { | |
1674 | pos += sprintf(buf + pos, "%s%s", | |
1675 | delim, disk_events_strs[i]); | |
1676 | delim = " "; | |
1677 | } | |
1678 | if (pos) | |
1679 | pos += sprintf(buf + pos, "\n"); | |
1680 | return pos; | |
1681 | } | |
1682 | ||
1683 | static ssize_t disk_events_show(struct device *dev, | |
1684 | struct device_attribute *attr, char *buf) | |
1685 | { | |
1686 | struct gendisk *disk = dev_to_disk(dev); | |
1687 | ||
1688 | return __disk_events_show(disk->events, buf); | |
1689 | } | |
1690 | ||
1691 | static ssize_t disk_events_async_show(struct device *dev, | |
1692 | struct device_attribute *attr, char *buf) | |
1693 | { | |
1694 | struct gendisk *disk = dev_to_disk(dev); | |
1695 | ||
1696 | return __disk_events_show(disk->async_events, buf); | |
1697 | } | |
1698 | ||
1699 | static ssize_t disk_events_poll_msecs_show(struct device *dev, | |
1700 | struct device_attribute *attr, | |
1701 | char *buf) | |
1702 | { | |
1703 | struct gendisk *disk = dev_to_disk(dev); | |
1704 | ||
1705 | return sprintf(buf, "%ld\n", disk->ev->poll_msecs); | |
1706 | } | |
1707 | ||
1708 | static ssize_t disk_events_poll_msecs_store(struct device *dev, | |
1709 | struct device_attribute *attr, | |
1710 | const char *buf, size_t count) | |
1711 | { | |
1712 | struct gendisk *disk = dev_to_disk(dev); | |
1713 | long intv; | |
1714 | ||
1715 | if (!count || !sscanf(buf, "%ld", &intv)) | |
1716 | return -EINVAL; | |
1717 | ||
1718 | if (intv < 0 && intv != -1) | |
1719 | return -EINVAL; | |
1720 | ||
c3af54af | 1721 | disk_block_events(disk); |
77ea887e TH |
1722 | disk->ev->poll_msecs = intv; |
1723 | __disk_unblock_events(disk, true); | |
1724 | ||
1725 | return count; | |
1726 | } | |
1727 | ||
1728 | static const DEVICE_ATTR(events, S_IRUGO, disk_events_show, NULL); | |
1729 | static const DEVICE_ATTR(events_async, S_IRUGO, disk_events_async_show, NULL); | |
1730 | static const DEVICE_ATTR(events_poll_msecs, S_IRUGO|S_IWUSR, | |
1731 | disk_events_poll_msecs_show, | |
1732 | disk_events_poll_msecs_store); | |
1733 | ||
1734 | static const struct attribute *disk_events_attrs[] = { | |
1735 | &dev_attr_events.attr, | |
1736 | &dev_attr_events_async.attr, | |
1737 | &dev_attr_events_poll_msecs.attr, | |
1738 | NULL, | |
1739 | }; | |
1740 | ||
1741 | /* | |
1742 | * The default polling interval can be specified by the kernel | |
1743 | * parameter block.events_dfl_poll_msecs which defaults to 0 | |
1744 | * (disable). This can also be modified runtime by writing to | |
1745 | * /sys/module/block/events_dfl_poll_msecs. | |
1746 | */ | |
1747 | static int disk_events_set_dfl_poll_msecs(const char *val, | |
1748 | const struct kernel_param *kp) | |
1749 | { | |
1750 | struct disk_events *ev; | |
1751 | int ret; | |
1752 | ||
1753 | ret = param_set_ulong(val, kp); | |
1754 | if (ret < 0) | |
1755 | return ret; | |
1756 | ||
1757 | mutex_lock(&disk_events_mutex); | |
1758 | ||
1759 | list_for_each_entry(ev, &disk_events, node) | |
85ef06d1 | 1760 | disk_flush_events(ev->disk, 0); |
77ea887e TH |
1761 | |
1762 | mutex_unlock(&disk_events_mutex); | |
1763 | ||
1764 | return 0; | |
1765 | } | |
1766 | ||
1767 | static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops = { | |
1768 | .set = disk_events_set_dfl_poll_msecs, | |
1769 | .get = param_get_ulong, | |
1770 | }; | |
1771 | ||
1772 | #undef MODULE_PARAM_PREFIX | |
1773 | #define MODULE_PARAM_PREFIX "block." | |
1774 | ||
1775 | module_param_cb(events_dfl_poll_msecs, &disk_events_dfl_poll_msecs_param_ops, | |
1776 | &disk_events_dfl_poll_msecs, 0644); | |
1777 | ||
1778 | /* | |
9f53d2fe | 1779 | * disk_{alloc|add|del|release}_events - initialize and destroy disk_events. |
77ea887e | 1780 | */ |
9f53d2fe | 1781 | static void disk_alloc_events(struct gendisk *disk) |
77ea887e TH |
1782 | { |
1783 | struct disk_events *ev; | |
1784 | ||
75e3f3ee | 1785 | if (!disk->fops->check_events) |
77ea887e TH |
1786 | return; |
1787 | ||
1788 | ev = kzalloc(sizeof(*ev), GFP_KERNEL); | |
1789 | if (!ev) { | |
1790 | pr_warn("%s: failed to initialize events\n", disk->disk_name); | |
1791 | return; | |
1792 | } | |
1793 | ||
77ea887e TH |
1794 | INIT_LIST_HEAD(&ev->node); |
1795 | ev->disk = disk; | |
1796 | spin_lock_init(&ev->lock); | |
fdd514e1 | 1797 | mutex_init(&ev->block_mutex); |
77ea887e TH |
1798 | ev->block = 1; |
1799 | ev->poll_msecs = -1; | |
1800 | INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn); | |
1801 | ||
9f53d2fe SG |
1802 | disk->ev = ev; |
1803 | } | |
1804 | ||
1805 | static void disk_add_events(struct gendisk *disk) | |
1806 | { | |
1807 | if (!disk->ev) | |
1808 | return; | |
1809 | ||
1810 | /* FIXME: error handling */ | |
1811 | if (sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs) < 0) | |
1812 | pr_warn("%s: failed to create sysfs files for events\n", | |
1813 | disk->disk_name); | |
1814 | ||
77ea887e | 1815 | mutex_lock(&disk_events_mutex); |
9f53d2fe | 1816 | list_add_tail(&disk->ev->node, &disk_events); |
77ea887e TH |
1817 | mutex_unlock(&disk_events_mutex); |
1818 | ||
1819 | /* | |
1820 | * Block count is initialized to 1 and the following initial | |
1821 | * unblock kicks it into action. | |
1822 | */ | |
1823 | __disk_unblock_events(disk, true); | |
1824 | } | |
1825 | ||
1826 | static void disk_del_events(struct gendisk *disk) | |
1827 | { | |
1828 | if (!disk->ev) | |
1829 | return; | |
1830 | ||
c3af54af | 1831 | disk_block_events(disk); |
77ea887e TH |
1832 | |
1833 | mutex_lock(&disk_events_mutex); | |
1834 | list_del_init(&disk->ev->node); | |
1835 | mutex_unlock(&disk_events_mutex); | |
1836 | ||
1837 | sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs); | |
1838 | } | |
1839 | ||
1840 | static void disk_release_events(struct gendisk *disk) | |
1841 | { | |
1842 | /* the block count should be 1 from disk_del_events() */ | |
1843 | WARN_ON_ONCE(disk->ev && disk->ev->block != 1); | |
1844 | kfree(disk->ev); | |
1845 | } |