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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/fs/block_dev.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE | |
6 | */ | |
7 | ||
1da177e4 LT |
8 | #include <linux/init.h> |
9 | #include <linux/mm.h> | |
10 | #include <linux/fcntl.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/kmod.h> | |
13 | #include <linux/major.h> | |
1da177e4 | 14 | #include <linux/smp_lock.h> |
7db9cfd3 | 15 | #include <linux/device_cgroup.h> |
1da177e4 LT |
16 | #include <linux/highmem.h> |
17 | #include <linux/blkdev.h> | |
18 | #include <linux/module.h> | |
19 | #include <linux/blkpg.h> | |
20 | #include <linux/buffer_head.h> | |
585d3bc0 | 21 | #include <linux/pagevec.h> |
811d736f | 22 | #include <linux/writeback.h> |
1da177e4 LT |
23 | #include <linux/mpage.h> |
24 | #include <linux/mount.h> | |
25 | #include <linux/uio.h> | |
26 | #include <linux/namei.h> | |
1368c4f2 | 27 | #include <linux/log2.h> |
2e1483c9 | 28 | #include <linux/kmemleak.h> |
1da177e4 | 29 | #include <asm/uaccess.h> |
07f3f05c | 30 | #include "internal.h" |
1da177e4 LT |
31 | |
32 | struct bdev_inode { | |
33 | struct block_device bdev; | |
34 | struct inode vfs_inode; | |
35 | }; | |
36 | ||
4c54ac62 AB |
37 | static const struct address_space_operations def_blk_aops; |
38 | ||
1da177e4 LT |
39 | static inline struct bdev_inode *BDEV_I(struct inode *inode) |
40 | { | |
41 | return container_of(inode, struct bdev_inode, vfs_inode); | |
42 | } | |
43 | ||
44 | inline struct block_device *I_BDEV(struct inode *inode) | |
45 | { | |
46 | return &BDEV_I(inode)->bdev; | |
47 | } | |
48 | ||
49 | EXPORT_SYMBOL(I_BDEV); | |
50 | ||
51 | static sector_t max_block(struct block_device *bdev) | |
52 | { | |
53 | sector_t retval = ~((sector_t)0); | |
54 | loff_t sz = i_size_read(bdev->bd_inode); | |
55 | ||
56 | if (sz) { | |
57 | unsigned int size = block_size(bdev); | |
58 | unsigned int sizebits = blksize_bits(size); | |
59 | retval = (sz >> sizebits); | |
60 | } | |
61 | return retval; | |
62 | } | |
63 | ||
f9a14399 | 64 | /* Kill _all_ buffers and pagecache , dirty or not.. */ |
1da177e4 LT |
65 | static void kill_bdev(struct block_device *bdev) |
66 | { | |
f9a14399 PZ |
67 | if (bdev->bd_inode->i_mapping->nrpages == 0) |
68 | return; | |
69 | invalidate_bh_lrus(); | |
1da177e4 LT |
70 | truncate_inode_pages(bdev->bd_inode->i_mapping, 0); |
71 | } | |
72 | ||
73 | int set_blocksize(struct block_device *bdev, int size) | |
74 | { | |
75 | /* Size must be a power of two, and between 512 and PAGE_SIZE */ | |
1368c4f2 | 76 | if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size)) |
1da177e4 LT |
77 | return -EINVAL; |
78 | ||
79 | /* Size cannot be smaller than the size supported by the device */ | |
e1defc4f | 80 | if (size < bdev_logical_block_size(bdev)) |
1da177e4 LT |
81 | return -EINVAL; |
82 | ||
83 | /* Don't change the size if it is same as current */ | |
84 | if (bdev->bd_block_size != size) { | |
85 | sync_blockdev(bdev); | |
86 | bdev->bd_block_size = size; | |
87 | bdev->bd_inode->i_blkbits = blksize_bits(size); | |
88 | kill_bdev(bdev); | |
89 | } | |
90 | return 0; | |
91 | } | |
92 | ||
93 | EXPORT_SYMBOL(set_blocksize); | |
94 | ||
95 | int sb_set_blocksize(struct super_block *sb, int size) | |
96 | { | |
1da177e4 LT |
97 | if (set_blocksize(sb->s_bdev, size)) |
98 | return 0; | |
99 | /* If we get here, we know size is power of two | |
100 | * and it's value is between 512 and PAGE_SIZE */ | |
101 | sb->s_blocksize = size; | |
38885bd4 | 102 | sb->s_blocksize_bits = blksize_bits(size); |
1da177e4 LT |
103 | return sb->s_blocksize; |
104 | } | |
105 | ||
106 | EXPORT_SYMBOL(sb_set_blocksize); | |
107 | ||
108 | int sb_min_blocksize(struct super_block *sb, int size) | |
109 | { | |
e1defc4f | 110 | int minsize = bdev_logical_block_size(sb->s_bdev); |
1da177e4 LT |
111 | if (size < minsize) |
112 | size = minsize; | |
113 | return sb_set_blocksize(sb, size); | |
114 | } | |
115 | ||
116 | EXPORT_SYMBOL(sb_min_blocksize); | |
117 | ||
118 | static int | |
119 | blkdev_get_block(struct inode *inode, sector_t iblock, | |
120 | struct buffer_head *bh, int create) | |
121 | { | |
122 | if (iblock >= max_block(I_BDEV(inode))) { | |
123 | if (create) | |
124 | return -EIO; | |
125 | ||
126 | /* | |
127 | * for reads, we're just trying to fill a partial page. | |
128 | * return a hole, they will have to call get_block again | |
129 | * before they can fill it, and they will get -EIO at that | |
130 | * time | |
131 | */ | |
132 | return 0; | |
133 | } | |
134 | bh->b_bdev = I_BDEV(inode); | |
135 | bh->b_blocknr = iblock; | |
136 | set_buffer_mapped(bh); | |
137 | return 0; | |
138 | } | |
139 | ||
b2e895db AM |
140 | static int |
141 | blkdev_get_blocks(struct inode *inode, sector_t iblock, | |
142 | struct buffer_head *bh, int create) | |
143 | { | |
144 | sector_t end_block = max_block(I_BDEV(inode)); | |
145 | unsigned long max_blocks = bh->b_size >> inode->i_blkbits; | |
146 | ||
147 | if ((iblock + max_blocks) > end_block) { | |
148 | max_blocks = end_block - iblock; | |
149 | if ((long)max_blocks <= 0) { | |
150 | if (create) | |
151 | return -EIO; /* write fully beyond EOF */ | |
152 | /* | |
153 | * It is a read which is fully beyond EOF. We return | |
154 | * a !buffer_mapped buffer | |
155 | */ | |
156 | max_blocks = 0; | |
157 | } | |
158 | } | |
159 | ||
160 | bh->b_bdev = I_BDEV(inode); | |
161 | bh->b_blocknr = iblock; | |
162 | bh->b_size = max_blocks << inode->i_blkbits; | |
163 | if (max_blocks) | |
164 | set_buffer_mapped(bh); | |
165 | return 0; | |
166 | } | |
167 | ||
168 | static ssize_t | |
169 | blkdev_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov, | |
170 | loff_t offset, unsigned long nr_segs) | |
171 | { | |
172 | struct file *file = iocb->ki_filp; | |
173 | struct inode *inode = file->f_mapping->host; | |
174 | ||
175 | return blockdev_direct_IO_no_locking(rw, iocb, inode, I_BDEV(inode), | |
176 | iov, offset, nr_segs, blkdev_get_blocks, NULL); | |
177 | } | |
178 | ||
5cee5815 JK |
179 | int __sync_blockdev(struct block_device *bdev, int wait) |
180 | { | |
181 | if (!bdev) | |
182 | return 0; | |
183 | if (!wait) | |
184 | return filemap_flush(bdev->bd_inode->i_mapping); | |
185 | return filemap_write_and_wait(bdev->bd_inode->i_mapping); | |
186 | } | |
187 | ||
585d3bc0 NP |
188 | /* |
189 | * Write out and wait upon all the dirty data associated with a block | |
190 | * device via its mapping. Does not take the superblock lock. | |
191 | */ | |
192 | int sync_blockdev(struct block_device *bdev) | |
193 | { | |
5cee5815 | 194 | return __sync_blockdev(bdev, 1); |
585d3bc0 NP |
195 | } |
196 | EXPORT_SYMBOL(sync_blockdev); | |
197 | ||
198 | /* | |
199 | * Write out and wait upon all dirty data associated with this | |
200 | * device. Filesystem data as well as the underlying block | |
201 | * device. Takes the superblock lock. | |
202 | */ | |
203 | int fsync_bdev(struct block_device *bdev) | |
204 | { | |
205 | struct super_block *sb = get_super(bdev); | |
206 | if (sb) { | |
60b0680f | 207 | int res = sync_filesystem(sb); |
585d3bc0 NP |
208 | drop_super(sb); |
209 | return res; | |
210 | } | |
211 | return sync_blockdev(bdev); | |
212 | } | |
47e4491b | 213 | EXPORT_SYMBOL(fsync_bdev); |
585d3bc0 NP |
214 | |
215 | /** | |
216 | * freeze_bdev -- lock a filesystem and force it into a consistent state | |
217 | * @bdev: blockdevice to lock | |
218 | * | |
585d3bc0 NP |
219 | * If a superblock is found on this device, we take the s_umount semaphore |
220 | * on it to make sure nobody unmounts until the snapshot creation is done. | |
221 | * The reference counter (bd_fsfreeze_count) guarantees that only the last | |
222 | * unfreeze process can unfreeze the frozen filesystem actually when multiple | |
223 | * freeze requests arrive simultaneously. It counts up in freeze_bdev() and | |
224 | * count down in thaw_bdev(). When it becomes 0, thaw_bdev() will unfreeze | |
225 | * actually. | |
226 | */ | |
227 | struct super_block *freeze_bdev(struct block_device *bdev) | |
228 | { | |
229 | struct super_block *sb; | |
230 | int error = 0; | |
231 | ||
232 | mutex_lock(&bdev->bd_fsfreeze_mutex); | |
4504230a CH |
233 | if (++bdev->bd_fsfreeze_count > 1) { |
234 | /* | |
235 | * We don't even need to grab a reference - the first call | |
236 | * to freeze_bdev grab an active reference and only the last | |
237 | * thaw_bdev drops it. | |
238 | */ | |
585d3bc0 | 239 | sb = get_super(bdev); |
4504230a CH |
240 | drop_super(sb); |
241 | mutex_unlock(&bdev->bd_fsfreeze_mutex); | |
242 | return sb; | |
243 | } | |
244 | ||
245 | sb = get_active_super(bdev); | |
246 | if (!sb) | |
247 | goto out; | |
248 | if (sb->s_flags & MS_RDONLY) { | |
4b06e5b9 JN |
249 | sb->s_frozen = SB_FREEZE_TRANS; |
250 | up_write(&sb->s_umount); | |
585d3bc0 NP |
251 | mutex_unlock(&bdev->bd_fsfreeze_mutex); |
252 | return sb; | |
253 | } | |
4504230a CH |
254 | |
255 | sb->s_frozen = SB_FREEZE_WRITE; | |
256 | smp_wmb(); | |
257 | ||
258 | sync_filesystem(sb); | |
259 | ||
260 | sb->s_frozen = SB_FREEZE_TRANS; | |
261 | smp_wmb(); | |
262 | ||
263 | sync_blockdev(sb->s_bdev); | |
264 | ||
265 | if (sb->s_op->freeze_fs) { | |
266 | error = sb->s_op->freeze_fs(sb); | |
267 | if (error) { | |
268 | printk(KERN_ERR | |
269 | "VFS:Filesystem freeze failed\n"); | |
270 | sb->s_frozen = SB_UNFROZEN; | |
271 | deactivate_locked_super(sb); | |
272 | bdev->bd_fsfreeze_count--; | |
273 | mutex_unlock(&bdev->bd_fsfreeze_mutex); | |
274 | return ERR_PTR(error); | |
585d3bc0 NP |
275 | } |
276 | } | |
4504230a | 277 | up_write(&sb->s_umount); |
585d3bc0 | 278 | |
4504230a | 279 | out: |
585d3bc0 NP |
280 | sync_blockdev(bdev); |
281 | mutex_unlock(&bdev->bd_fsfreeze_mutex); | |
4fadd7bb | 282 | return sb; /* thaw_bdev releases s->s_umount */ |
585d3bc0 NP |
283 | } |
284 | EXPORT_SYMBOL(freeze_bdev); | |
285 | ||
286 | /** | |
287 | * thaw_bdev -- unlock filesystem | |
288 | * @bdev: blockdevice to unlock | |
289 | * @sb: associated superblock | |
290 | * | |
291 | * Unlocks the filesystem and marks it writeable again after freeze_bdev(). | |
292 | */ | |
293 | int thaw_bdev(struct block_device *bdev, struct super_block *sb) | |
294 | { | |
4504230a | 295 | int error = -EINVAL; |
585d3bc0 NP |
296 | |
297 | mutex_lock(&bdev->bd_fsfreeze_mutex); | |
4504230a CH |
298 | if (!bdev->bd_fsfreeze_count) |
299 | goto out_unlock; | |
300 | ||
301 | error = 0; | |
302 | if (--bdev->bd_fsfreeze_count > 0) | |
303 | goto out_unlock; | |
304 | ||
305 | if (!sb) | |
306 | goto out_unlock; | |
307 | ||
308 | BUG_ON(sb->s_bdev != bdev); | |
309 | down_write(&sb->s_umount); | |
310 | if (sb->s_flags & MS_RDONLY) | |
4b06e5b9 | 311 | goto out_unfrozen; |
4504230a CH |
312 | |
313 | if (sb->s_op->unfreeze_fs) { | |
314 | error = sb->s_op->unfreeze_fs(sb); | |
315 | if (error) { | |
316 | printk(KERN_ERR | |
317 | "VFS:Filesystem thaw failed\n"); | |
318 | sb->s_frozen = SB_FREEZE_TRANS; | |
319 | bdev->bd_fsfreeze_count++; | |
320 | mutex_unlock(&bdev->bd_fsfreeze_mutex); | |
321 | return error; | |
585d3bc0 | 322 | } |
585d3bc0 NP |
323 | } |
324 | ||
4b06e5b9 | 325 | out_unfrozen: |
4504230a CH |
326 | sb->s_frozen = SB_UNFROZEN; |
327 | smp_wmb(); | |
328 | wake_up(&sb->s_wait_unfrozen); | |
329 | ||
4504230a CH |
330 | if (sb) |
331 | deactivate_locked_super(sb); | |
332 | out_unlock: | |
585d3bc0 NP |
333 | mutex_unlock(&bdev->bd_fsfreeze_mutex); |
334 | return 0; | |
335 | } | |
336 | EXPORT_SYMBOL(thaw_bdev); | |
337 | ||
1da177e4 LT |
338 | static int blkdev_writepage(struct page *page, struct writeback_control *wbc) |
339 | { | |
340 | return block_write_full_page(page, blkdev_get_block, wbc); | |
341 | } | |
342 | ||
343 | static int blkdev_readpage(struct file * file, struct page * page) | |
344 | { | |
345 | return block_read_full_page(page, blkdev_get_block); | |
346 | } | |
347 | ||
6272b5a5 NP |
348 | static int blkdev_write_begin(struct file *file, struct address_space *mapping, |
349 | loff_t pos, unsigned len, unsigned flags, | |
350 | struct page **pagep, void **fsdata) | |
1da177e4 | 351 | { |
6272b5a5 NP |
352 | *pagep = NULL; |
353 | return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, | |
354 | blkdev_get_block); | |
1da177e4 LT |
355 | } |
356 | ||
6272b5a5 NP |
357 | static int blkdev_write_end(struct file *file, struct address_space *mapping, |
358 | loff_t pos, unsigned len, unsigned copied, | |
359 | struct page *page, void *fsdata) | |
1da177e4 | 360 | { |
6272b5a5 NP |
361 | int ret; |
362 | ret = block_write_end(file, mapping, pos, len, copied, page, fsdata); | |
363 | ||
364 | unlock_page(page); | |
365 | page_cache_release(page); | |
366 | ||
367 | return ret; | |
1da177e4 LT |
368 | } |
369 | ||
370 | /* | |
371 | * private llseek: | |
0f7fc9e4 | 372 | * for a block special file file->f_path.dentry->d_inode->i_size is zero |
1da177e4 LT |
373 | * so we compute the size by hand (just as in block_read/write above) |
374 | */ | |
375 | static loff_t block_llseek(struct file *file, loff_t offset, int origin) | |
376 | { | |
377 | struct inode *bd_inode = file->f_mapping->host; | |
378 | loff_t size; | |
379 | loff_t retval; | |
380 | ||
1b1dcc1b | 381 | mutex_lock(&bd_inode->i_mutex); |
1da177e4 LT |
382 | size = i_size_read(bd_inode); |
383 | ||
384 | switch (origin) { | |
385 | case 2: | |
386 | offset += size; | |
387 | break; | |
388 | case 1: | |
389 | offset += file->f_pos; | |
390 | } | |
391 | retval = -EINVAL; | |
392 | if (offset >= 0 && offset <= size) { | |
393 | if (offset != file->f_pos) { | |
394 | file->f_pos = offset; | |
395 | } | |
396 | retval = offset; | |
397 | } | |
1b1dcc1b | 398 | mutex_unlock(&bd_inode->i_mutex); |
1da177e4 LT |
399 | return retval; |
400 | } | |
401 | ||
402 | /* | |
403 | * Filp is never NULL; the only case when ->fsync() is called with | |
404 | * NULL first argument is nfsd_sync_dir() and that's not a directory. | |
405 | */ | |
406 | ||
b1dd3b28 | 407 | int blkdev_fsync(struct file *filp, struct dentry *dentry, int datasync) |
1da177e4 | 408 | { |
ab0a9735 CH |
409 | struct block_device *bdev = I_BDEV(filp->f_mapping->host); |
410 | int error; | |
411 | ||
412 | error = sync_blockdev(bdev); | |
413 | if (error) | |
414 | return error; | |
415 | ||
416 | error = blkdev_issue_flush(bdev, NULL); | |
417 | if (error == -EOPNOTSUPP) | |
418 | error = 0; | |
419 | return error; | |
1da177e4 | 420 | } |
b1dd3b28 | 421 | EXPORT_SYMBOL(blkdev_fsync); |
1da177e4 LT |
422 | |
423 | /* | |
424 | * pseudo-fs | |
425 | */ | |
426 | ||
427 | static __cacheline_aligned_in_smp DEFINE_SPINLOCK(bdev_lock); | |
e18b890b | 428 | static struct kmem_cache * bdev_cachep __read_mostly; |
1da177e4 LT |
429 | |
430 | static struct inode *bdev_alloc_inode(struct super_block *sb) | |
431 | { | |
e94b1766 | 432 | struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL); |
1da177e4 LT |
433 | if (!ei) |
434 | return NULL; | |
435 | return &ei->vfs_inode; | |
436 | } | |
437 | ||
438 | static void bdev_destroy_inode(struct inode *inode) | |
439 | { | |
440 | struct bdev_inode *bdi = BDEV_I(inode); | |
441 | ||
1da177e4 LT |
442 | kmem_cache_free(bdev_cachep, bdi); |
443 | } | |
444 | ||
51cc5068 | 445 | static void init_once(void *foo) |
1da177e4 LT |
446 | { |
447 | struct bdev_inode *ei = (struct bdev_inode *) foo; | |
448 | struct block_device *bdev = &ei->bdev; | |
449 | ||
a35afb83 CL |
450 | memset(bdev, 0, sizeof(*bdev)); |
451 | mutex_init(&bdev->bd_mutex); | |
a35afb83 CL |
452 | INIT_LIST_HEAD(&bdev->bd_inodes); |
453 | INIT_LIST_HEAD(&bdev->bd_list); | |
641dc636 | 454 | #ifdef CONFIG_SYSFS |
a35afb83 | 455 | INIT_LIST_HEAD(&bdev->bd_holder_list); |
641dc636 | 456 | #endif |
a35afb83 | 457 | inode_init_once(&ei->vfs_inode); |
fcccf502 TS |
458 | /* Initialize mutex for freeze. */ |
459 | mutex_init(&bdev->bd_fsfreeze_mutex); | |
1da177e4 LT |
460 | } |
461 | ||
462 | static inline void __bd_forget(struct inode *inode) | |
463 | { | |
464 | list_del_init(&inode->i_devices); | |
465 | inode->i_bdev = NULL; | |
466 | inode->i_mapping = &inode->i_data; | |
467 | } | |
468 | ||
469 | static void bdev_clear_inode(struct inode *inode) | |
470 | { | |
471 | struct block_device *bdev = &BDEV_I(inode)->bdev; | |
472 | struct list_head *p; | |
473 | spin_lock(&bdev_lock); | |
474 | while ( (p = bdev->bd_inodes.next) != &bdev->bd_inodes ) { | |
475 | __bd_forget(list_entry(p, struct inode, i_devices)); | |
476 | } | |
477 | list_del_init(&bdev->bd_list); | |
478 | spin_unlock(&bdev_lock); | |
479 | } | |
480 | ||
ee9b6d61 | 481 | static const struct super_operations bdev_sops = { |
1da177e4 LT |
482 | .statfs = simple_statfs, |
483 | .alloc_inode = bdev_alloc_inode, | |
484 | .destroy_inode = bdev_destroy_inode, | |
485 | .drop_inode = generic_delete_inode, | |
486 | .clear_inode = bdev_clear_inode, | |
487 | }; | |
488 | ||
454e2398 DH |
489 | static int bd_get_sb(struct file_system_type *fs_type, |
490 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) | |
1da177e4 | 491 | { |
454e2398 | 492 | return get_sb_pseudo(fs_type, "bdev:", &bdev_sops, 0x62646576, mnt); |
1da177e4 LT |
493 | } |
494 | ||
495 | static struct file_system_type bd_type = { | |
496 | .name = "bdev", | |
497 | .get_sb = bd_get_sb, | |
498 | .kill_sb = kill_anon_super, | |
499 | }; | |
500 | ||
c2acf7b9 | 501 | struct super_block *blockdev_superblock __read_mostly; |
1da177e4 LT |
502 | |
503 | void __init bdev_cache_init(void) | |
504 | { | |
505 | int err; | |
c2acf7b9 DC |
506 | struct vfsmount *bd_mnt; |
507 | ||
1da177e4 | 508 | bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode), |
fffb60f9 PJ |
509 | 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| |
510 | SLAB_MEM_SPREAD|SLAB_PANIC), | |
20c2df83 | 511 | init_once); |
1da177e4 LT |
512 | err = register_filesystem(&bd_type); |
513 | if (err) | |
514 | panic("Cannot register bdev pseudo-fs"); | |
515 | bd_mnt = kern_mount(&bd_type); | |
1da177e4 LT |
516 | if (IS_ERR(bd_mnt)) |
517 | panic("Cannot create bdev pseudo-fs"); | |
2e1483c9 CM |
518 | /* |
519 | * This vfsmount structure is only used to obtain the | |
520 | * blockdev_superblock, so tell kmemleak not to report it. | |
521 | */ | |
522 | kmemleak_not_leak(bd_mnt); | |
1da177e4 LT |
523 | blockdev_superblock = bd_mnt->mnt_sb; /* For writeback */ |
524 | } | |
525 | ||
526 | /* | |
527 | * Most likely _very_ bad one - but then it's hardly critical for small | |
528 | * /dev and can be fixed when somebody will need really large one. | |
529 | * Keep in mind that it will be fed through icache hash function too. | |
530 | */ | |
531 | static inline unsigned long hash(dev_t dev) | |
532 | { | |
533 | return MAJOR(dev)+MINOR(dev); | |
534 | } | |
535 | ||
536 | static int bdev_test(struct inode *inode, void *data) | |
537 | { | |
538 | return BDEV_I(inode)->bdev.bd_dev == *(dev_t *)data; | |
539 | } | |
540 | ||
541 | static int bdev_set(struct inode *inode, void *data) | |
542 | { | |
543 | BDEV_I(inode)->bdev.bd_dev = *(dev_t *)data; | |
544 | return 0; | |
545 | } | |
546 | ||
547 | static LIST_HEAD(all_bdevs); | |
548 | ||
549 | struct block_device *bdget(dev_t dev) | |
550 | { | |
551 | struct block_device *bdev; | |
552 | struct inode *inode; | |
553 | ||
c2acf7b9 | 554 | inode = iget5_locked(blockdev_superblock, hash(dev), |
1da177e4 LT |
555 | bdev_test, bdev_set, &dev); |
556 | ||
557 | if (!inode) | |
558 | return NULL; | |
559 | ||
560 | bdev = &BDEV_I(inode)->bdev; | |
561 | ||
562 | if (inode->i_state & I_NEW) { | |
563 | bdev->bd_contains = NULL; | |
564 | bdev->bd_inode = inode; | |
565 | bdev->bd_block_size = (1 << inode->i_blkbits); | |
566 | bdev->bd_part_count = 0; | |
567 | bdev->bd_invalidated = 0; | |
568 | inode->i_mode = S_IFBLK; | |
569 | inode->i_rdev = dev; | |
570 | inode->i_bdev = bdev; | |
571 | inode->i_data.a_ops = &def_blk_aops; | |
572 | mapping_set_gfp_mask(&inode->i_data, GFP_USER); | |
573 | inode->i_data.backing_dev_info = &default_backing_dev_info; | |
574 | spin_lock(&bdev_lock); | |
575 | list_add(&bdev->bd_list, &all_bdevs); | |
576 | spin_unlock(&bdev_lock); | |
577 | unlock_new_inode(inode); | |
578 | } | |
579 | return bdev; | |
580 | } | |
581 | ||
582 | EXPORT_SYMBOL(bdget); | |
583 | ||
dddac6a7 AJ |
584 | /** |
585 | * bdgrab -- Grab a reference to an already referenced block device | |
586 | * @bdev: Block device to grab a reference to. | |
587 | */ | |
588 | struct block_device *bdgrab(struct block_device *bdev) | |
589 | { | |
590 | atomic_inc(&bdev->bd_inode->i_count); | |
591 | return bdev; | |
592 | } | |
593 | ||
1da177e4 LT |
594 | long nr_blockdev_pages(void) |
595 | { | |
203a2935 | 596 | struct block_device *bdev; |
1da177e4 LT |
597 | long ret = 0; |
598 | spin_lock(&bdev_lock); | |
203a2935 | 599 | list_for_each_entry(bdev, &all_bdevs, bd_list) { |
1da177e4 LT |
600 | ret += bdev->bd_inode->i_mapping->nrpages; |
601 | } | |
602 | spin_unlock(&bdev_lock); | |
603 | return ret; | |
604 | } | |
605 | ||
606 | void bdput(struct block_device *bdev) | |
607 | { | |
608 | iput(bdev->bd_inode); | |
609 | } | |
610 | ||
611 | EXPORT_SYMBOL(bdput); | |
612 | ||
613 | static struct block_device *bd_acquire(struct inode *inode) | |
614 | { | |
615 | struct block_device *bdev; | |
09d967c6 | 616 | |
1da177e4 LT |
617 | spin_lock(&bdev_lock); |
618 | bdev = inode->i_bdev; | |
09d967c6 OH |
619 | if (bdev) { |
620 | atomic_inc(&bdev->bd_inode->i_count); | |
1da177e4 LT |
621 | spin_unlock(&bdev_lock); |
622 | return bdev; | |
623 | } | |
624 | spin_unlock(&bdev_lock); | |
09d967c6 | 625 | |
1da177e4 LT |
626 | bdev = bdget(inode->i_rdev); |
627 | if (bdev) { | |
628 | spin_lock(&bdev_lock); | |
09d967c6 OH |
629 | if (!inode->i_bdev) { |
630 | /* | |
631 | * We take an additional bd_inode->i_count for inode, | |
632 | * and it's released in clear_inode() of inode. | |
633 | * So, we can access it via ->i_mapping always | |
634 | * without igrab(). | |
635 | */ | |
636 | atomic_inc(&bdev->bd_inode->i_count); | |
637 | inode->i_bdev = bdev; | |
638 | inode->i_mapping = bdev->bd_inode->i_mapping; | |
639 | list_add(&inode->i_devices, &bdev->bd_inodes); | |
640 | } | |
1da177e4 LT |
641 | spin_unlock(&bdev_lock); |
642 | } | |
643 | return bdev; | |
644 | } | |
645 | ||
646 | /* Call when you free inode */ | |
647 | ||
648 | void bd_forget(struct inode *inode) | |
649 | { | |
09d967c6 OH |
650 | struct block_device *bdev = NULL; |
651 | ||
1da177e4 | 652 | spin_lock(&bdev_lock); |
09d967c6 | 653 | if (inode->i_bdev) { |
c2acf7b9 | 654 | if (!sb_is_blkdev_sb(inode->i_sb)) |
09d967c6 | 655 | bdev = inode->i_bdev; |
1da177e4 | 656 | __bd_forget(inode); |
09d967c6 | 657 | } |
1da177e4 | 658 | spin_unlock(&bdev_lock); |
09d967c6 OH |
659 | |
660 | if (bdev) | |
661 | iput(bdev->bd_inode); | |
1da177e4 LT |
662 | } |
663 | ||
664 | int bd_claim(struct block_device *bdev, void *holder) | |
665 | { | |
666 | int res; | |
667 | spin_lock(&bdev_lock); | |
668 | ||
669 | /* first decide result */ | |
670 | if (bdev->bd_holder == holder) | |
671 | res = 0; /* already a holder */ | |
672 | else if (bdev->bd_holder != NULL) | |
673 | res = -EBUSY; /* held by someone else */ | |
674 | else if (bdev->bd_contains == bdev) | |
675 | res = 0; /* is a whole device which isn't held */ | |
676 | ||
677 | else if (bdev->bd_contains->bd_holder == bd_claim) | |
678 | res = 0; /* is a partition of a device that is being partitioned */ | |
679 | else if (bdev->bd_contains->bd_holder != NULL) | |
680 | res = -EBUSY; /* is a partition of a held device */ | |
681 | else | |
682 | res = 0; /* is a partition of an un-held device */ | |
683 | ||
684 | /* now impose change */ | |
685 | if (res==0) { | |
686 | /* note that for a whole device bd_holders | |
687 | * will be incremented twice, and bd_holder will | |
688 | * be set to bd_claim before being set to holder | |
689 | */ | |
690 | bdev->bd_contains->bd_holders ++; | |
691 | bdev->bd_contains->bd_holder = bd_claim; | |
692 | bdev->bd_holders++; | |
693 | bdev->bd_holder = holder; | |
694 | } | |
695 | spin_unlock(&bdev_lock); | |
696 | return res; | |
697 | } | |
698 | ||
699 | EXPORT_SYMBOL(bd_claim); | |
700 | ||
701 | void bd_release(struct block_device *bdev) | |
702 | { | |
703 | spin_lock(&bdev_lock); | |
704 | if (!--bdev->bd_contains->bd_holders) | |
705 | bdev->bd_contains->bd_holder = NULL; | |
706 | if (!--bdev->bd_holders) | |
707 | bdev->bd_holder = NULL; | |
708 | spin_unlock(&bdev_lock); | |
709 | } | |
710 | ||
711 | EXPORT_SYMBOL(bd_release); | |
712 | ||
641dc636 JN |
713 | #ifdef CONFIG_SYSFS |
714 | /* | |
715 | * Functions for bd_claim_by_kobject / bd_release_from_kobject | |
716 | * | |
717 | * If a kobject is passed to bd_claim_by_kobject() | |
718 | * and the kobject has a parent directory, | |
719 | * following symlinks are created: | |
720 | * o from the kobject to the claimed bdev | |
721 | * o from "holders" directory of the bdev to the parent of the kobject | |
722 | * bd_release_from_kobject() removes these symlinks. | |
723 | * | |
724 | * Example: | |
725 | * If /dev/dm-0 maps to /dev/sda, kobject corresponding to | |
726 | * /sys/block/dm-0/slaves is passed to bd_claim_by_kobject(), then: | |
727 | * /sys/block/dm-0/slaves/sda --> /sys/block/sda | |
728 | * /sys/block/sda/holders/dm-0 --> /sys/block/dm-0 | |
729 | */ | |
730 | ||
4d7dd8fd | 731 | static int add_symlink(struct kobject *from, struct kobject *to) |
641dc636 JN |
732 | { |
733 | if (!from || !to) | |
4d7dd8fd AM |
734 | return 0; |
735 | return sysfs_create_link(from, to, kobject_name(to)); | |
641dc636 JN |
736 | } |
737 | ||
738 | static void del_symlink(struct kobject *from, struct kobject *to) | |
739 | { | |
740 | if (!from || !to) | |
741 | return; | |
742 | sysfs_remove_link(from, kobject_name(to)); | |
743 | } | |
744 | ||
745 | /* | |
746 | * 'struct bd_holder' contains pointers to kobjects symlinked by | |
747 | * bd_claim_by_kobject. | |
748 | * It's connected to bd_holder_list which is protected by bdev->bd_sem. | |
749 | */ | |
750 | struct bd_holder { | |
751 | struct list_head list; /* chain of holders of the bdev */ | |
752 | int count; /* references from the holder */ | |
753 | struct kobject *sdir; /* holder object, e.g. "/block/dm-0/slaves" */ | |
754 | struct kobject *hdev; /* e.g. "/block/dm-0" */ | |
755 | struct kobject *hdir; /* e.g. "/block/sda/holders" */ | |
756 | struct kobject *sdev; /* e.g. "/block/sda" */ | |
757 | }; | |
758 | ||
759 | /* | |
760 | * Get references of related kobjects at once. | |
761 | * Returns 1 on success. 0 on failure. | |
762 | * | |
763 | * Should call bd_holder_release_dirs() after successful use. | |
764 | */ | |
765 | static int bd_holder_grab_dirs(struct block_device *bdev, | |
766 | struct bd_holder *bo) | |
767 | { | |
768 | if (!bdev || !bo) | |
769 | return 0; | |
770 | ||
771 | bo->sdir = kobject_get(bo->sdir); | |
772 | if (!bo->sdir) | |
773 | return 0; | |
774 | ||
775 | bo->hdev = kobject_get(bo->sdir->parent); | |
776 | if (!bo->hdev) | |
777 | goto fail_put_sdir; | |
778 | ||
0762b8bd | 779 | bo->sdev = kobject_get(&part_to_dev(bdev->bd_part)->kobj); |
641dc636 JN |
780 | if (!bo->sdev) |
781 | goto fail_put_hdev; | |
782 | ||
4c46501d | 783 | bo->hdir = kobject_get(bdev->bd_part->holder_dir); |
641dc636 JN |
784 | if (!bo->hdir) |
785 | goto fail_put_sdev; | |
786 | ||
787 | return 1; | |
788 | ||
789 | fail_put_sdev: | |
790 | kobject_put(bo->sdev); | |
791 | fail_put_hdev: | |
792 | kobject_put(bo->hdev); | |
793 | fail_put_sdir: | |
794 | kobject_put(bo->sdir); | |
795 | ||
796 | return 0; | |
797 | } | |
798 | ||
799 | /* Put references of related kobjects at once. */ | |
800 | static void bd_holder_release_dirs(struct bd_holder *bo) | |
801 | { | |
802 | kobject_put(bo->hdir); | |
803 | kobject_put(bo->sdev); | |
804 | kobject_put(bo->hdev); | |
805 | kobject_put(bo->sdir); | |
806 | } | |
807 | ||
808 | static struct bd_holder *alloc_bd_holder(struct kobject *kobj) | |
809 | { | |
810 | struct bd_holder *bo; | |
811 | ||
812 | bo = kzalloc(sizeof(*bo), GFP_KERNEL); | |
813 | if (!bo) | |
814 | return NULL; | |
815 | ||
816 | bo->count = 1; | |
817 | bo->sdir = kobj; | |
818 | ||
819 | return bo; | |
820 | } | |
821 | ||
822 | static void free_bd_holder(struct bd_holder *bo) | |
823 | { | |
824 | kfree(bo); | |
825 | } | |
826 | ||
df6c0cd9 JN |
827 | /** |
828 | * find_bd_holder - find matching struct bd_holder from the block device | |
829 | * | |
830 | * @bdev: struct block device to be searched | |
831 | * @bo: target struct bd_holder | |
832 | * | |
833 | * Returns matching entry with @bo in @bdev->bd_holder_list. | |
834 | * If found, increment the reference count and return the pointer. | |
835 | * If not found, returns NULL. | |
836 | */ | |
36a561d6 AM |
837 | static struct bd_holder *find_bd_holder(struct block_device *bdev, |
838 | struct bd_holder *bo) | |
df6c0cd9 JN |
839 | { |
840 | struct bd_holder *tmp; | |
841 | ||
842 | list_for_each_entry(tmp, &bdev->bd_holder_list, list) | |
843 | if (tmp->sdir == bo->sdir) { | |
844 | tmp->count++; | |
845 | return tmp; | |
846 | } | |
847 | ||
848 | return NULL; | |
849 | } | |
850 | ||
641dc636 JN |
851 | /** |
852 | * add_bd_holder - create sysfs symlinks for bd_claim() relationship | |
853 | * | |
854 | * @bdev: block device to be bd_claimed | |
855 | * @bo: preallocated and initialized by alloc_bd_holder() | |
856 | * | |
df6c0cd9 | 857 | * Add @bo to @bdev->bd_holder_list, create symlinks. |
641dc636 | 858 | * |
df6c0cd9 JN |
859 | * Returns 0 if symlinks are created. |
860 | * Returns -ve if something fails. | |
641dc636 JN |
861 | */ |
862 | static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo) | |
863 | { | |
4e91672c | 864 | int err; |
641dc636 JN |
865 | |
866 | if (!bo) | |
4d7dd8fd | 867 | return -EINVAL; |
641dc636 | 868 | |
641dc636 | 869 | if (!bd_holder_grab_dirs(bdev, bo)) |
4d7dd8fd | 870 | return -EBUSY; |
641dc636 | 871 | |
4e91672c JW |
872 | err = add_symlink(bo->sdir, bo->sdev); |
873 | if (err) | |
874 | return err; | |
875 | ||
876 | err = add_symlink(bo->hdir, bo->hdev); | |
877 | if (err) { | |
878 | del_symlink(bo->sdir, bo->sdev); | |
879 | return err; | |
4d7dd8fd | 880 | } |
4e91672c JW |
881 | |
882 | list_add_tail(&bo->list, &bdev->bd_holder_list); | |
883 | return 0; | |
641dc636 JN |
884 | } |
885 | ||
886 | /** | |
887 | * del_bd_holder - delete sysfs symlinks for bd_claim() relationship | |
888 | * | |
889 | * @bdev: block device to be bd_claimed | |
890 | * @kobj: holder's kobject | |
891 | * | |
892 | * If there is matching entry with @kobj in @bdev->bd_holder_list | |
893 | * and no other bd_claim() from the same kobject, | |
894 | * remove the struct bd_holder from the list, delete symlinks for it. | |
895 | * | |
896 | * Returns a pointer to the struct bd_holder when it's removed from the list | |
897 | * and ready to be freed. | |
898 | * Returns NULL if matching claim isn't found or there is other bd_claim() | |
899 | * by the same kobject. | |
900 | */ | |
901 | static struct bd_holder *del_bd_holder(struct block_device *bdev, | |
902 | struct kobject *kobj) | |
903 | { | |
904 | struct bd_holder *bo; | |
905 | ||
906 | list_for_each_entry(bo, &bdev->bd_holder_list, list) { | |
907 | if (bo->sdir == kobj) { | |
908 | bo->count--; | |
909 | BUG_ON(bo->count < 0); | |
910 | if (!bo->count) { | |
911 | list_del(&bo->list); | |
912 | del_symlink(bo->sdir, bo->sdev); | |
913 | del_symlink(bo->hdir, bo->hdev); | |
914 | bd_holder_release_dirs(bo); | |
915 | return bo; | |
916 | } | |
917 | break; | |
918 | } | |
919 | } | |
920 | ||
921 | return NULL; | |
922 | } | |
923 | ||
924 | /** | |
925 | * bd_claim_by_kobject - bd_claim() with additional kobject signature | |
926 | * | |
927 | * @bdev: block device to be claimed | |
928 | * @holder: holder's signature | |
929 | * @kobj: holder's kobject | |
930 | * | |
931 | * Do bd_claim() and if it succeeds, create sysfs symlinks between | |
932 | * the bdev and the holder's kobject. | |
933 | * Use bd_release_from_kobject() when relesing the claimed bdev. | |
934 | * | |
935 | * Returns 0 on success. (same as bd_claim()) | |
936 | * Returns errno on failure. | |
937 | */ | |
938 | static int bd_claim_by_kobject(struct block_device *bdev, void *holder, | |
939 | struct kobject *kobj) | |
940 | { | |
4e91672c | 941 | int err; |
df6c0cd9 | 942 | struct bd_holder *bo, *found; |
641dc636 JN |
943 | |
944 | if (!kobj) | |
945 | return -EINVAL; | |
946 | ||
947 | bo = alloc_bd_holder(kobj); | |
948 | if (!bo) | |
949 | return -ENOMEM; | |
950 | ||
2e7b651d | 951 | mutex_lock(&bdev->bd_mutex); |
df6c0cd9 | 952 | |
4e91672c JW |
953 | err = bd_claim(bdev, holder); |
954 | if (err) | |
4210df28 | 955 | goto fail; |
4e91672c JW |
956 | |
957 | found = find_bd_holder(bdev, bo); | |
958 | if (found) | |
4210df28 | 959 | goto fail; |
4e91672c JW |
960 | |
961 | err = add_bd_holder(bdev, bo); | |
962 | if (err) | |
963 | bd_release(bdev); | |
4210df28 AM |
964 | else |
965 | bo = NULL; | |
966 | fail: | |
b4cf1b72 | 967 | mutex_unlock(&bdev->bd_mutex); |
4210df28 | 968 | free_bd_holder(bo); |
4e91672c | 969 | return err; |
641dc636 JN |
970 | } |
971 | ||
972 | /** | |
973 | * bd_release_from_kobject - bd_release() with additional kobject signature | |
974 | * | |
975 | * @bdev: block device to be released | |
976 | * @kobj: holder's kobject | |
977 | * | |
978 | * Do bd_release() and remove sysfs symlinks created by bd_claim_by_kobject(). | |
979 | */ | |
980 | static void bd_release_from_kobject(struct block_device *bdev, | |
981 | struct kobject *kobj) | |
982 | { | |
641dc636 JN |
983 | if (!kobj) |
984 | return; | |
985 | ||
2e7b651d | 986 | mutex_lock(&bdev->bd_mutex); |
641dc636 | 987 | bd_release(bdev); |
4210df28 | 988 | free_bd_holder(del_bd_holder(bdev, kobj)); |
b4cf1b72 | 989 | mutex_unlock(&bdev->bd_mutex); |
641dc636 JN |
990 | } |
991 | ||
992 | /** | |
993 | * bd_claim_by_disk - wrapper function for bd_claim_by_kobject() | |
994 | * | |
995 | * @bdev: block device to be claimed | |
996 | * @holder: holder's signature | |
997 | * @disk: holder's gendisk | |
998 | * | |
999 | * Call bd_claim_by_kobject() with getting @disk->slave_dir. | |
1000 | */ | |
1001 | int bd_claim_by_disk(struct block_device *bdev, void *holder, | |
1002 | struct gendisk *disk) | |
1003 | { | |
1004 | return bd_claim_by_kobject(bdev, holder, kobject_get(disk->slave_dir)); | |
1005 | } | |
1006 | EXPORT_SYMBOL_GPL(bd_claim_by_disk); | |
1007 | ||
1008 | /** | |
1009 | * bd_release_from_disk - wrapper function for bd_release_from_kobject() | |
1010 | * | |
1011 | * @bdev: block device to be claimed | |
1012 | * @disk: holder's gendisk | |
1013 | * | |
1014 | * Call bd_release_from_kobject() and put @disk->slave_dir. | |
1015 | */ | |
1016 | void bd_release_from_disk(struct block_device *bdev, struct gendisk *disk) | |
1017 | { | |
1018 | bd_release_from_kobject(bdev, disk->slave_dir); | |
1019 | kobject_put(disk->slave_dir); | |
1020 | } | |
1021 | EXPORT_SYMBOL_GPL(bd_release_from_disk); | |
1022 | #endif | |
1023 | ||
1da177e4 LT |
1024 | /* |
1025 | * Tries to open block device by device number. Use it ONLY if you | |
1026 | * really do not have anything better - i.e. when you are behind a | |
1027 | * truly sucky interface and all you are given is a device number. _Never_ | |
1028 | * to be used for internal purposes. If you ever need it - reconsider | |
1029 | * your API. | |
1030 | */ | |
aeb5d727 | 1031 | struct block_device *open_by_devnum(dev_t dev, fmode_t mode) |
1da177e4 LT |
1032 | { |
1033 | struct block_device *bdev = bdget(dev); | |
1034 | int err = -ENOMEM; | |
1da177e4 | 1035 | if (bdev) |
572c4892 | 1036 | err = blkdev_get(bdev, mode); |
1da177e4 LT |
1037 | return err ? ERR_PTR(err) : bdev; |
1038 | } | |
1039 | ||
1040 | EXPORT_SYMBOL(open_by_devnum); | |
1041 | ||
56ade44b AP |
1042 | /** |
1043 | * flush_disk - invalidates all buffer-cache entries on a disk | |
1044 | * | |
1045 | * @bdev: struct block device to be flushed | |
1046 | * | |
1047 | * Invalidates all buffer-cache entries on a disk. It should be called | |
1048 | * when a disk has been changed -- either by a media change or online | |
1049 | * resize. | |
1050 | */ | |
1051 | static void flush_disk(struct block_device *bdev) | |
1052 | { | |
1053 | if (__invalidate_device(bdev)) { | |
1054 | char name[BDEVNAME_SIZE] = ""; | |
1055 | ||
1056 | if (bdev->bd_disk) | |
1057 | disk_name(bdev->bd_disk, 0, name); | |
1058 | printk(KERN_WARNING "VFS: busy inodes on changed media or " | |
1059 | "resized disk %s\n", name); | |
1060 | } | |
1061 | ||
1062 | if (!bdev->bd_disk) | |
1063 | return; | |
1064 | if (disk_partitionable(bdev->bd_disk)) | |
1065 | bdev->bd_invalidated = 1; | |
1066 | } | |
1067 | ||
c3279d14 | 1068 | /** |
57d1b536 | 1069 | * check_disk_size_change - checks for disk size change and adjusts bdev size. |
c3279d14 AP |
1070 | * @disk: struct gendisk to check |
1071 | * @bdev: struct bdev to adjust. | |
1072 | * | |
1073 | * This routine checks to see if the bdev size does not match the disk size | |
1074 | * and adjusts it if it differs. | |
1075 | */ | |
1076 | void check_disk_size_change(struct gendisk *disk, struct block_device *bdev) | |
1077 | { | |
1078 | loff_t disk_size, bdev_size; | |
1079 | ||
1080 | disk_size = (loff_t)get_capacity(disk) << 9; | |
1081 | bdev_size = i_size_read(bdev->bd_inode); | |
1082 | if (disk_size != bdev_size) { | |
1083 | char name[BDEVNAME_SIZE]; | |
1084 | ||
1085 | disk_name(disk, 0, name); | |
1086 | printk(KERN_INFO | |
1087 | "%s: detected capacity change from %lld to %lld\n", | |
1088 | name, bdev_size, disk_size); | |
1089 | i_size_write(bdev->bd_inode, disk_size); | |
608aeef1 | 1090 | flush_disk(bdev); |
c3279d14 AP |
1091 | } |
1092 | } | |
1093 | EXPORT_SYMBOL(check_disk_size_change); | |
1094 | ||
0c002c2f | 1095 | /** |
57d1b536 | 1096 | * revalidate_disk - wrapper for lower-level driver's revalidate_disk call-back |
0c002c2f AP |
1097 | * @disk: struct gendisk to be revalidated |
1098 | * | |
1099 | * This routine is a wrapper for lower-level driver's revalidate_disk | |
1100 | * call-backs. It is used to do common pre and post operations needed | |
1101 | * for all revalidate_disk operations. | |
1102 | */ | |
1103 | int revalidate_disk(struct gendisk *disk) | |
1104 | { | |
c3279d14 | 1105 | struct block_device *bdev; |
0c002c2f AP |
1106 | int ret = 0; |
1107 | ||
1108 | if (disk->fops->revalidate_disk) | |
1109 | ret = disk->fops->revalidate_disk(disk); | |
1110 | ||
c3279d14 AP |
1111 | bdev = bdget_disk(disk, 0); |
1112 | if (!bdev) | |
1113 | return ret; | |
1114 | ||
1115 | mutex_lock(&bdev->bd_mutex); | |
1116 | check_disk_size_change(disk, bdev); | |
1117 | mutex_unlock(&bdev->bd_mutex); | |
1118 | bdput(bdev); | |
0c002c2f AP |
1119 | return ret; |
1120 | } | |
1121 | EXPORT_SYMBOL(revalidate_disk); | |
1122 | ||
1da177e4 LT |
1123 | /* |
1124 | * This routine checks whether a removable media has been changed, | |
1125 | * and invalidates all buffer-cache-entries in that case. This | |
1126 | * is a relatively slow routine, so we have to try to minimize using | |
1127 | * it. Thus it is called only upon a 'mount' or 'open'. This | |
1128 | * is the best way of combining speed and utility, I think. | |
1129 | * People changing diskettes in the middle of an operation deserve | |
1130 | * to lose :-) | |
1131 | */ | |
1132 | int check_disk_change(struct block_device *bdev) | |
1133 | { | |
1134 | struct gendisk *disk = bdev->bd_disk; | |
83d5cde4 | 1135 | const struct block_device_operations *bdops = disk->fops; |
1da177e4 LT |
1136 | |
1137 | if (!bdops->media_changed) | |
1138 | return 0; | |
1139 | if (!bdops->media_changed(bdev->bd_disk)) | |
1140 | return 0; | |
1141 | ||
56ade44b | 1142 | flush_disk(bdev); |
1da177e4 LT |
1143 | if (bdops->revalidate_disk) |
1144 | bdops->revalidate_disk(bdev->bd_disk); | |
1da177e4 LT |
1145 | return 1; |
1146 | } | |
1147 | ||
1148 | EXPORT_SYMBOL(check_disk_change); | |
1149 | ||
1150 | void bd_set_size(struct block_device *bdev, loff_t size) | |
1151 | { | |
e1defc4f | 1152 | unsigned bsize = bdev_logical_block_size(bdev); |
1da177e4 LT |
1153 | |
1154 | bdev->bd_inode->i_size = size; | |
1155 | while (bsize < PAGE_CACHE_SIZE) { | |
1156 | if (size & bsize) | |
1157 | break; | |
1158 | bsize <<= 1; | |
1159 | } | |
1160 | bdev->bd_block_size = bsize; | |
1161 | bdev->bd_inode->i_blkbits = blksize_bits(bsize); | |
1162 | } | |
1163 | EXPORT_SYMBOL(bd_set_size); | |
1164 | ||
9a1c3542 | 1165 | static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part); |
37be4124 | 1166 | |
6d740cd5 PZ |
1167 | /* |
1168 | * bd_mutex locking: | |
1169 | * | |
1170 | * mutex_lock(part->bd_mutex) | |
1171 | * mutex_lock_nested(whole->bd_mutex, 1) | |
1172 | */ | |
1173 | ||
572c4892 | 1174 | static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) |
1da177e4 | 1175 | { |
1da177e4 | 1176 | struct gendisk *disk; |
7db9cfd3 | 1177 | int ret; |
cf771cb5 | 1178 | int partno; |
fe6e9c1f AV |
1179 | int perm = 0; |
1180 | ||
572c4892 | 1181 | if (mode & FMODE_READ) |
fe6e9c1f | 1182 | perm |= MAY_READ; |
572c4892 | 1183 | if (mode & FMODE_WRITE) |
fe6e9c1f AV |
1184 | perm |= MAY_WRITE; |
1185 | /* | |
1186 | * hooks: /n/, see "layering violations". | |
1187 | */ | |
1188 | ret = devcgroup_inode_permission(bdev->bd_inode, perm); | |
82666020 AV |
1189 | if (ret != 0) { |
1190 | bdput(bdev); | |
7db9cfd3 | 1191 | return ret; |
82666020 | 1192 | } |
7db9cfd3 | 1193 | |
1da177e4 | 1194 | lock_kernel(); |
d3374825 | 1195 | restart: |
0762b8bd | 1196 | |
89f97496 | 1197 | ret = -ENXIO; |
cf771cb5 | 1198 | disk = get_gendisk(bdev->bd_dev, &partno); |
0762b8bd TH |
1199 | if (!disk) |
1200 | goto out_unlock_kernel; | |
1da177e4 | 1201 | |
6796bf54 | 1202 | mutex_lock_nested(&bdev->bd_mutex, for_part); |
1da177e4 LT |
1203 | if (!bdev->bd_openers) { |
1204 | bdev->bd_disk = disk; | |
1205 | bdev->bd_contains = bdev; | |
cf771cb5 | 1206 | if (!partno) { |
1da177e4 | 1207 | struct backing_dev_info *bdi; |
89f97496 TH |
1208 | |
1209 | ret = -ENXIO; | |
1210 | bdev->bd_part = disk_get_part(disk, partno); | |
1211 | if (!bdev->bd_part) | |
1212 | goto out_clear; | |
1213 | ||
1da177e4 | 1214 | if (disk->fops->open) { |
572c4892 | 1215 | ret = disk->fops->open(bdev, mode); |
d3374825 N |
1216 | if (ret == -ERESTARTSYS) { |
1217 | /* Lost a race with 'disk' being | |
1218 | * deleted, try again. | |
1219 | * See md.c | |
1220 | */ | |
1221 | disk_put_part(bdev->bd_part); | |
1222 | bdev->bd_part = NULL; | |
1223 | module_put(disk->fops->owner); | |
1224 | put_disk(disk); | |
1225 | bdev->bd_disk = NULL; | |
1226 | mutex_unlock(&bdev->bd_mutex); | |
1227 | goto restart; | |
1228 | } | |
1da177e4 | 1229 | if (ret) |
0762b8bd | 1230 | goto out_clear; |
1da177e4 LT |
1231 | } |
1232 | if (!bdev->bd_openers) { | |
1233 | bd_set_size(bdev,(loff_t)get_capacity(disk)<<9); | |
1234 | bdi = blk_get_backing_dev_info(bdev); | |
1235 | if (bdi == NULL) | |
1236 | bdi = &default_backing_dev_info; | |
1237 | bdev->bd_inode->i_data.backing_dev_info = bdi; | |
1238 | } | |
1239 | if (bdev->bd_invalidated) | |
1240 | rescan_partitions(disk, bdev); | |
1241 | } else { | |
1da177e4 LT |
1242 | struct block_device *whole; |
1243 | whole = bdget_disk(disk, 0); | |
1244 | ret = -ENOMEM; | |
1245 | if (!whole) | |
0762b8bd | 1246 | goto out_clear; |
37be4124 | 1247 | BUG_ON(for_part); |
572c4892 | 1248 | ret = __blkdev_get(whole, mode, 1); |
1da177e4 | 1249 | if (ret) |
0762b8bd | 1250 | goto out_clear; |
1da177e4 | 1251 | bdev->bd_contains = whole; |
1da177e4 LT |
1252 | bdev->bd_inode->i_data.backing_dev_info = |
1253 | whole->bd_inode->i_data.backing_dev_info; | |
89f97496 | 1254 | bdev->bd_part = disk_get_part(disk, partno); |
e71bf0d0 | 1255 | if (!(disk->flags & GENHD_FL_UP) || |
89f97496 | 1256 | !bdev->bd_part || !bdev->bd_part->nr_sects) { |
1da177e4 | 1257 | ret = -ENXIO; |
0762b8bd | 1258 | goto out_clear; |
1da177e4 | 1259 | } |
89f97496 | 1260 | bd_set_size(bdev, (loff_t)bdev->bd_part->nr_sects << 9); |
1da177e4 LT |
1261 | } |
1262 | } else { | |
0762b8bd | 1263 | module_put(disk->fops->owner); |
960cc0f4 | 1264 | put_disk(disk); |
0762b8bd | 1265 | disk = NULL; |
1da177e4 LT |
1266 | if (bdev->bd_contains == bdev) { |
1267 | if (bdev->bd_disk->fops->open) { | |
572c4892 | 1268 | ret = bdev->bd_disk->fops->open(bdev, mode); |
1da177e4 | 1269 | if (ret) |
0762b8bd | 1270 | goto out_unlock_bdev; |
1da177e4 LT |
1271 | } |
1272 | if (bdev->bd_invalidated) | |
1273 | rescan_partitions(bdev->bd_disk, bdev); | |
1da177e4 LT |
1274 | } |
1275 | } | |
1276 | bdev->bd_openers++; | |
37be4124 N |
1277 | if (for_part) |
1278 | bdev->bd_part_count++; | |
c039e313 | 1279 | mutex_unlock(&bdev->bd_mutex); |
1da177e4 LT |
1280 | unlock_kernel(); |
1281 | return 0; | |
1282 | ||
0762b8bd | 1283 | out_clear: |
89f97496 | 1284 | disk_put_part(bdev->bd_part); |
1da177e4 | 1285 | bdev->bd_disk = NULL; |
0762b8bd | 1286 | bdev->bd_part = NULL; |
1da177e4 LT |
1287 | bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info; |
1288 | if (bdev != bdev->bd_contains) | |
572c4892 | 1289 | __blkdev_put(bdev->bd_contains, mode, 1); |
1da177e4 | 1290 | bdev->bd_contains = NULL; |
0762b8bd | 1291 | out_unlock_bdev: |
c039e313 | 1292 | mutex_unlock(&bdev->bd_mutex); |
0762b8bd | 1293 | out_unlock_kernel: |
1da177e4 | 1294 | unlock_kernel(); |
0762b8bd | 1295 | |
0762b8bd TH |
1296 | if (disk) |
1297 | module_put(disk->fops->owner); | |
1298 | put_disk(disk); | |
1299 | bdput(bdev); | |
1300 | ||
1da177e4 LT |
1301 | return ret; |
1302 | } | |
1303 | ||
572c4892 | 1304 | int blkdev_get(struct block_device *bdev, fmode_t mode) |
1da177e4 | 1305 | { |
572c4892 | 1306 | return __blkdev_get(bdev, mode, 0); |
37be4124 | 1307 | } |
1da177e4 LT |
1308 | EXPORT_SYMBOL(blkdev_get); |
1309 | ||
1310 | static int blkdev_open(struct inode * inode, struct file * filp) | |
1311 | { | |
1312 | struct block_device *bdev; | |
1313 | int res; | |
1314 | ||
1315 | /* | |
1316 | * Preserve backwards compatibility and allow large file access | |
1317 | * even if userspace doesn't ask for it explicitly. Some mkfs | |
1318 | * binary needs it. We might want to drop this workaround | |
1319 | * during an unstable branch. | |
1320 | */ | |
1321 | filp->f_flags |= O_LARGEFILE; | |
1322 | ||
572c4892 AV |
1323 | if (filp->f_flags & O_NDELAY) |
1324 | filp->f_mode |= FMODE_NDELAY; | |
1325 | if (filp->f_flags & O_EXCL) | |
1326 | filp->f_mode |= FMODE_EXCL; | |
1327 | if ((filp->f_flags & O_ACCMODE) == 3) | |
1328 | filp->f_mode |= FMODE_WRITE_IOCTL; | |
1329 | ||
1da177e4 | 1330 | bdev = bd_acquire(inode); |
6a2aae06 PE |
1331 | if (bdev == NULL) |
1332 | return -ENOMEM; | |
1da177e4 | 1333 | |
572c4892 AV |
1334 | filp->f_mapping = bdev->bd_inode->i_mapping; |
1335 | ||
1336 | res = blkdev_get(bdev, filp->f_mode); | |
1da177e4 LT |
1337 | if (res) |
1338 | return res; | |
1339 | ||
ebbefc01 CH |
1340 | if (filp->f_mode & FMODE_EXCL) { |
1341 | res = bd_claim(bdev, filp); | |
1342 | if (res) | |
1343 | goto out_blkdev_put; | |
1344 | } | |
1da177e4 | 1345 | |
ebbefc01 | 1346 | return 0; |
1da177e4 | 1347 | |
ebbefc01 | 1348 | out_blkdev_put: |
9a1c3542 | 1349 | blkdev_put(bdev, filp->f_mode); |
1da177e4 LT |
1350 | return res; |
1351 | } | |
1352 | ||
9a1c3542 | 1353 | static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part) |
2e7b651d PZ |
1354 | { |
1355 | int ret = 0; | |
2e7b651d | 1356 | struct gendisk *disk = bdev->bd_disk; |
37be4124 | 1357 | struct block_device *victim = NULL; |
2e7b651d | 1358 | |
6796bf54 | 1359 | mutex_lock_nested(&bdev->bd_mutex, for_part); |
2e7b651d | 1360 | lock_kernel(); |
37be4124 N |
1361 | if (for_part) |
1362 | bdev->bd_part_count--; | |
1363 | ||
2e7b651d PZ |
1364 | if (!--bdev->bd_openers) { |
1365 | sync_blockdev(bdev); | |
1366 | kill_bdev(bdev); | |
1367 | } | |
1368 | if (bdev->bd_contains == bdev) { | |
1369 | if (disk->fops->release) | |
9a1c3542 | 1370 | ret = disk->fops->release(disk, mode); |
2e7b651d PZ |
1371 | } |
1372 | if (!bdev->bd_openers) { | |
1373 | struct module *owner = disk->fops->owner; | |
1374 | ||
1375 | put_disk(disk); | |
1376 | module_put(owner); | |
0762b8bd TH |
1377 | disk_put_part(bdev->bd_part); |
1378 | bdev->bd_part = NULL; | |
2e7b651d PZ |
1379 | bdev->bd_disk = NULL; |
1380 | bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info; | |
37be4124 N |
1381 | if (bdev != bdev->bd_contains) |
1382 | victim = bdev->bd_contains; | |
2e7b651d PZ |
1383 | bdev->bd_contains = NULL; |
1384 | } | |
1385 | unlock_kernel(); | |
1386 | mutex_unlock(&bdev->bd_mutex); | |
1387 | bdput(bdev); | |
37be4124 | 1388 | if (victim) |
9a1c3542 | 1389 | __blkdev_put(victim, mode, 1); |
2e7b651d PZ |
1390 | return ret; |
1391 | } | |
1392 | ||
9a1c3542 | 1393 | int blkdev_put(struct block_device *bdev, fmode_t mode) |
37be4124 | 1394 | { |
9a1c3542 | 1395 | return __blkdev_put(bdev, mode, 0); |
37be4124 | 1396 | } |
2e7b651d PZ |
1397 | EXPORT_SYMBOL(blkdev_put); |
1398 | ||
1da177e4 LT |
1399 | static int blkdev_close(struct inode * inode, struct file * filp) |
1400 | { | |
1401 | struct block_device *bdev = I_BDEV(filp->f_mapping->host); | |
1402 | if (bdev->bd_holder == filp) | |
1403 | bd_release(bdev); | |
9a1c3542 | 1404 | return blkdev_put(bdev, filp->f_mode); |
1da177e4 LT |
1405 | } |
1406 | ||
bb93e3a5 | 1407 | static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg) |
1da177e4 | 1408 | { |
56b26add AV |
1409 | struct block_device *bdev = I_BDEV(file->f_mapping->host); |
1410 | fmode_t mode = file->f_mode; | |
fd4ce1ac CH |
1411 | |
1412 | /* | |
1413 | * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have | |
1414 | * to updated it before every ioctl. | |
1415 | */ | |
56b26add | 1416 | if (file->f_flags & O_NDELAY) |
fd4ce1ac CH |
1417 | mode |= FMODE_NDELAY; |
1418 | else | |
1419 | mode &= ~FMODE_NDELAY; | |
1420 | ||
56b26add | 1421 | return blkdev_ioctl(bdev, mode, cmd, arg); |
1da177e4 LT |
1422 | } |
1423 | ||
eef99380 CH |
1424 | /* |
1425 | * Write data to the block device. Only intended for the block device itself | |
1426 | * and the raw driver which basically is a fake block device. | |
1427 | * | |
1428 | * Does not take i_mutex for the write and thus is not for general purpose | |
1429 | * use. | |
1430 | */ | |
1431 | ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, | |
1432 | unsigned long nr_segs, loff_t pos) | |
1433 | { | |
1434 | struct file *file = iocb->ki_filp; | |
1435 | ssize_t ret; | |
1436 | ||
1437 | BUG_ON(iocb->ki_pos != pos); | |
1438 | ||
1439 | ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos); | |
1440 | if (ret > 0 || ret == -EIOCBQUEUED) { | |
1441 | ssize_t err; | |
1442 | ||
1443 | err = generic_write_sync(file, pos, ret); | |
1444 | if (err < 0 && ret > 0) | |
1445 | ret = err; | |
1446 | } | |
1447 | return ret; | |
1448 | } | |
1449 | EXPORT_SYMBOL_GPL(blkdev_aio_write); | |
1450 | ||
87d8fe1e TT |
1451 | /* |
1452 | * Try to release a page associated with block device when the system | |
1453 | * is under memory pressure. | |
1454 | */ | |
1455 | static int blkdev_releasepage(struct page *page, gfp_t wait) | |
1456 | { | |
1457 | struct super_block *super = BDEV_I(page->mapping->host)->bdev.bd_super; | |
1458 | ||
1459 | if (super && super->s_op->bdev_try_to_free_page) | |
1460 | return super->s_op->bdev_try_to_free_page(super, page, wait); | |
1461 | ||
1462 | return try_to_free_buffers(page); | |
1463 | } | |
1464 | ||
4c54ac62 | 1465 | static const struct address_space_operations def_blk_aops = { |
1da177e4 LT |
1466 | .readpage = blkdev_readpage, |
1467 | .writepage = blkdev_writepage, | |
1468 | .sync_page = block_sync_page, | |
6272b5a5 NP |
1469 | .write_begin = blkdev_write_begin, |
1470 | .write_end = blkdev_write_end, | |
1da177e4 | 1471 | .writepages = generic_writepages, |
87d8fe1e | 1472 | .releasepage = blkdev_releasepage, |
1da177e4 LT |
1473 | .direct_IO = blkdev_direct_IO, |
1474 | }; | |
1475 | ||
4b6f5d20 | 1476 | const struct file_operations def_blk_fops = { |
1da177e4 LT |
1477 | .open = blkdev_open, |
1478 | .release = blkdev_close, | |
1479 | .llseek = block_llseek, | |
543ade1f BP |
1480 | .read = do_sync_read, |
1481 | .write = do_sync_write, | |
1da177e4 | 1482 | .aio_read = generic_file_aio_read, |
eef99380 | 1483 | .aio_write = blkdev_aio_write, |
1da177e4 | 1484 | .mmap = generic_file_mmap, |
b1dd3b28 | 1485 | .fsync = blkdev_fsync, |
bb93e3a5 | 1486 | .unlocked_ioctl = block_ioctl, |
1da177e4 LT |
1487 | #ifdef CONFIG_COMPAT |
1488 | .compat_ioctl = compat_blkdev_ioctl, | |
1489 | #endif | |
7f9c51f0 JA |
1490 | .splice_read = generic_file_splice_read, |
1491 | .splice_write = generic_file_splice_write, | |
1da177e4 LT |
1492 | }; |
1493 | ||
1494 | int ioctl_by_bdev(struct block_device *bdev, unsigned cmd, unsigned long arg) | |
1495 | { | |
1496 | int res; | |
1497 | mm_segment_t old_fs = get_fs(); | |
1498 | set_fs(KERNEL_DS); | |
56b26add | 1499 | res = blkdev_ioctl(bdev, 0, cmd, arg); |
1da177e4 LT |
1500 | set_fs(old_fs); |
1501 | return res; | |
1502 | } | |
1503 | ||
1504 | EXPORT_SYMBOL(ioctl_by_bdev); | |
1505 | ||
1506 | /** | |
1507 | * lookup_bdev - lookup a struct block_device by name | |
94e2959e | 1508 | * @pathname: special file representing the block device |
1da177e4 | 1509 | * |
57d1b536 | 1510 | * Get a reference to the blockdevice at @pathname in the current |
1da177e4 LT |
1511 | * namespace if possible and return it. Return ERR_PTR(error) |
1512 | * otherwise. | |
1513 | */ | |
421748ec | 1514 | struct block_device *lookup_bdev(const char *pathname) |
1da177e4 LT |
1515 | { |
1516 | struct block_device *bdev; | |
1517 | struct inode *inode; | |
421748ec | 1518 | struct path path; |
1da177e4 LT |
1519 | int error; |
1520 | ||
421748ec | 1521 | if (!pathname || !*pathname) |
1da177e4 LT |
1522 | return ERR_PTR(-EINVAL); |
1523 | ||
421748ec | 1524 | error = kern_path(pathname, LOOKUP_FOLLOW, &path); |
1da177e4 LT |
1525 | if (error) |
1526 | return ERR_PTR(error); | |
1527 | ||
421748ec | 1528 | inode = path.dentry->d_inode; |
1da177e4 LT |
1529 | error = -ENOTBLK; |
1530 | if (!S_ISBLK(inode->i_mode)) | |
1531 | goto fail; | |
1532 | error = -EACCES; | |
421748ec | 1533 | if (path.mnt->mnt_flags & MNT_NODEV) |
1da177e4 LT |
1534 | goto fail; |
1535 | error = -ENOMEM; | |
1536 | bdev = bd_acquire(inode); | |
1537 | if (!bdev) | |
1538 | goto fail; | |
1539 | out: | |
421748ec | 1540 | path_put(&path); |
1da177e4 LT |
1541 | return bdev; |
1542 | fail: | |
1543 | bdev = ERR_PTR(error); | |
1544 | goto out; | |
1545 | } | |
d5686b44 | 1546 | EXPORT_SYMBOL(lookup_bdev); |
1da177e4 LT |
1547 | |
1548 | /** | |
30c40d2c | 1549 | * open_bdev_exclusive - open a block device by name and set it up for use |
1da177e4 LT |
1550 | * |
1551 | * @path: special file representing the block device | |
30c40d2c | 1552 | * @mode: FMODE_... combination to pass be used |
1da177e4 LT |
1553 | * @holder: owner for exclusion |
1554 | * | |
1555 | * Open the blockdevice described by the special file at @path, claim it | |
1556 | * for the @holder. | |
1557 | */ | |
30c40d2c | 1558 | struct block_device *open_bdev_exclusive(const char *path, fmode_t mode, void *holder) |
1da177e4 LT |
1559 | { |
1560 | struct block_device *bdev; | |
1da177e4 LT |
1561 | int error = 0; |
1562 | ||
1563 | bdev = lookup_bdev(path); | |
1564 | if (IS_ERR(bdev)) | |
1565 | return bdev; | |
1566 | ||
572c4892 | 1567 | error = blkdev_get(bdev, mode); |
1da177e4 LT |
1568 | if (error) |
1569 | return ERR_PTR(error); | |
1570 | error = -EACCES; | |
30c40d2c | 1571 | if ((mode & FMODE_WRITE) && bdev_read_only(bdev)) |
1da177e4 LT |
1572 | goto blkdev_put; |
1573 | error = bd_claim(bdev, holder); | |
1574 | if (error) | |
1575 | goto blkdev_put; | |
1576 | ||
1577 | return bdev; | |
1578 | ||
1579 | blkdev_put: | |
9a1c3542 | 1580 | blkdev_put(bdev, mode); |
1da177e4 LT |
1581 | return ERR_PTR(error); |
1582 | } | |
1583 | ||
30c40d2c | 1584 | EXPORT_SYMBOL(open_bdev_exclusive); |
1da177e4 LT |
1585 | |
1586 | /** | |
30c40d2c | 1587 | * close_bdev_exclusive - close a blockdevice opened by open_bdev_exclusive() |
1da177e4 LT |
1588 | * |
1589 | * @bdev: blockdevice to close | |
30c40d2c | 1590 | * @mode: mode, must match that used to open. |
1da177e4 | 1591 | * |
30c40d2c | 1592 | * This is the counterpart to open_bdev_exclusive(). |
1da177e4 | 1593 | */ |
30c40d2c | 1594 | void close_bdev_exclusive(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
1595 | { |
1596 | bd_release(bdev); | |
30c40d2c | 1597 | blkdev_put(bdev, mode); |
1da177e4 LT |
1598 | } |
1599 | ||
30c40d2c | 1600 | EXPORT_SYMBOL(close_bdev_exclusive); |
b71e8a4c DH |
1601 | |
1602 | int __invalidate_device(struct block_device *bdev) | |
1603 | { | |
1604 | struct super_block *sb = get_super(bdev); | |
1605 | int res = 0; | |
1606 | ||
1607 | if (sb) { | |
1608 | /* | |
1609 | * no need to lock the super, get_super holds the | |
1610 | * read mutex so the filesystem cannot go away | |
1611 | * under us (->put_super runs with the write lock | |
1612 | * hold). | |
1613 | */ | |
1614 | shrink_dcache_sb(sb); | |
1615 | res = invalidate_inodes(sb); | |
1616 | drop_super(sb); | |
1617 | } | |
f98393a6 | 1618 | invalidate_bdev(bdev); |
b71e8a4c DH |
1619 | return res; |
1620 | } | |
1621 | EXPORT_SYMBOL(__invalidate_device); |