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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; | |
d3f21473 | 248 | down_write(&sb->s_umount); |
4504230a | 249 | if (sb->s_flags & MS_RDONLY) { |
4b06e5b9 JN |
250 | sb->s_frozen = SB_FREEZE_TRANS; |
251 | up_write(&sb->s_umount); | |
585d3bc0 NP |
252 | mutex_unlock(&bdev->bd_fsfreeze_mutex); |
253 | return sb; | |
254 | } | |
4504230a CH |
255 | |
256 | sb->s_frozen = SB_FREEZE_WRITE; | |
257 | smp_wmb(); | |
258 | ||
259 | sync_filesystem(sb); | |
260 | ||
261 | sb->s_frozen = SB_FREEZE_TRANS; | |
262 | smp_wmb(); | |
263 | ||
264 | sync_blockdev(sb->s_bdev); | |
265 | ||
266 | if (sb->s_op->freeze_fs) { | |
267 | error = sb->s_op->freeze_fs(sb); | |
268 | if (error) { | |
269 | printk(KERN_ERR | |
270 | "VFS:Filesystem freeze failed\n"); | |
271 | sb->s_frozen = SB_UNFROZEN; | |
272 | deactivate_locked_super(sb); | |
273 | bdev->bd_fsfreeze_count--; | |
274 | mutex_unlock(&bdev->bd_fsfreeze_mutex); | |
275 | return ERR_PTR(error); | |
585d3bc0 NP |
276 | } |
277 | } | |
4504230a | 278 | up_write(&sb->s_umount); |
585d3bc0 | 279 | |
4504230a | 280 | out: |
585d3bc0 NP |
281 | sync_blockdev(bdev); |
282 | mutex_unlock(&bdev->bd_fsfreeze_mutex); | |
4fadd7bb | 283 | return sb; /* thaw_bdev releases s->s_umount */ |
585d3bc0 NP |
284 | } |
285 | EXPORT_SYMBOL(freeze_bdev); | |
286 | ||
287 | /** | |
288 | * thaw_bdev -- unlock filesystem | |
289 | * @bdev: blockdevice to unlock | |
290 | * @sb: associated superblock | |
291 | * | |
292 | * Unlocks the filesystem and marks it writeable again after freeze_bdev(). | |
293 | */ | |
294 | int thaw_bdev(struct block_device *bdev, struct super_block *sb) | |
295 | { | |
4504230a | 296 | int error = -EINVAL; |
585d3bc0 NP |
297 | |
298 | mutex_lock(&bdev->bd_fsfreeze_mutex); | |
4504230a CH |
299 | if (!bdev->bd_fsfreeze_count) |
300 | goto out_unlock; | |
301 | ||
302 | error = 0; | |
303 | if (--bdev->bd_fsfreeze_count > 0) | |
304 | goto out_unlock; | |
305 | ||
306 | if (!sb) | |
307 | goto out_unlock; | |
308 | ||
309 | BUG_ON(sb->s_bdev != bdev); | |
310 | down_write(&sb->s_umount); | |
311 | if (sb->s_flags & MS_RDONLY) | |
4b06e5b9 | 312 | goto out_unfrozen; |
4504230a CH |
313 | |
314 | if (sb->s_op->unfreeze_fs) { | |
315 | error = sb->s_op->unfreeze_fs(sb); | |
316 | if (error) { | |
317 | printk(KERN_ERR | |
318 | "VFS:Filesystem thaw failed\n"); | |
319 | sb->s_frozen = SB_FREEZE_TRANS; | |
320 | bdev->bd_fsfreeze_count++; | |
321 | mutex_unlock(&bdev->bd_fsfreeze_mutex); | |
322 | return error; | |
585d3bc0 | 323 | } |
585d3bc0 NP |
324 | } |
325 | ||
4b06e5b9 | 326 | out_unfrozen: |
4504230a CH |
327 | sb->s_frozen = SB_UNFROZEN; |
328 | smp_wmb(); | |
329 | wake_up(&sb->s_wait_unfrozen); | |
330 | ||
4504230a CH |
331 | if (sb) |
332 | deactivate_locked_super(sb); | |
333 | out_unlock: | |
585d3bc0 NP |
334 | mutex_unlock(&bdev->bd_fsfreeze_mutex); |
335 | return 0; | |
336 | } | |
337 | EXPORT_SYMBOL(thaw_bdev); | |
338 | ||
1da177e4 LT |
339 | static int blkdev_writepage(struct page *page, struct writeback_control *wbc) |
340 | { | |
341 | return block_write_full_page(page, blkdev_get_block, wbc); | |
342 | } | |
343 | ||
344 | static int blkdev_readpage(struct file * file, struct page * page) | |
345 | { | |
346 | return block_read_full_page(page, blkdev_get_block); | |
347 | } | |
348 | ||
6272b5a5 NP |
349 | static int blkdev_write_begin(struct file *file, struct address_space *mapping, |
350 | loff_t pos, unsigned len, unsigned flags, | |
351 | struct page **pagep, void **fsdata) | |
1da177e4 | 352 | { |
6272b5a5 NP |
353 | *pagep = NULL; |
354 | return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata, | |
355 | blkdev_get_block); | |
1da177e4 LT |
356 | } |
357 | ||
6272b5a5 NP |
358 | static int blkdev_write_end(struct file *file, struct address_space *mapping, |
359 | loff_t pos, unsigned len, unsigned copied, | |
360 | struct page *page, void *fsdata) | |
1da177e4 | 361 | { |
6272b5a5 NP |
362 | int ret; |
363 | ret = block_write_end(file, mapping, pos, len, copied, page, fsdata); | |
364 | ||
365 | unlock_page(page); | |
366 | page_cache_release(page); | |
367 | ||
368 | return ret; | |
1da177e4 LT |
369 | } |
370 | ||
371 | /* | |
372 | * private llseek: | |
0f7fc9e4 | 373 | * for a block special file file->f_path.dentry->d_inode->i_size is zero |
1da177e4 LT |
374 | * so we compute the size by hand (just as in block_read/write above) |
375 | */ | |
376 | static loff_t block_llseek(struct file *file, loff_t offset, int origin) | |
377 | { | |
378 | struct inode *bd_inode = file->f_mapping->host; | |
379 | loff_t size; | |
380 | loff_t retval; | |
381 | ||
1b1dcc1b | 382 | mutex_lock(&bd_inode->i_mutex); |
1da177e4 LT |
383 | size = i_size_read(bd_inode); |
384 | ||
385 | switch (origin) { | |
386 | case 2: | |
387 | offset += size; | |
388 | break; | |
389 | case 1: | |
390 | offset += file->f_pos; | |
391 | } | |
392 | retval = -EINVAL; | |
393 | if (offset >= 0 && offset <= size) { | |
394 | if (offset != file->f_pos) { | |
395 | file->f_pos = offset; | |
396 | } | |
397 | retval = offset; | |
398 | } | |
1b1dcc1b | 399 | mutex_unlock(&bd_inode->i_mutex); |
1da177e4 LT |
400 | return retval; |
401 | } | |
402 | ||
403 | /* | |
404 | * Filp is never NULL; the only case when ->fsync() is called with | |
405 | * NULL first argument is nfsd_sync_dir() and that's not a directory. | |
406 | */ | |
407 | ||
b1dd3b28 | 408 | int blkdev_fsync(struct file *filp, struct dentry *dentry, int datasync) |
1da177e4 | 409 | { |
b8af67e2 AB |
410 | struct inode *bd_inode = filp->f_mapping->host; |
411 | struct block_device *bdev = I_BDEV(bd_inode); | |
ab0a9735 CH |
412 | int error; |
413 | ||
b8af67e2 AB |
414 | /* |
415 | * There is no need to serialise calls to blkdev_issue_flush with | |
416 | * i_mutex and doing so causes performance issues with concurrent | |
417 | * O_SYNC writers to a block device. | |
418 | */ | |
419 | mutex_unlock(&bd_inode->i_mutex); | |
420 | ||
ab0a9735 CH |
421 | error = blkdev_issue_flush(bdev, NULL); |
422 | if (error == -EOPNOTSUPP) | |
423 | error = 0; | |
b8af67e2 AB |
424 | |
425 | mutex_lock(&bd_inode->i_mutex); | |
426 | ||
ab0a9735 | 427 | return error; |
1da177e4 | 428 | } |
b1dd3b28 | 429 | EXPORT_SYMBOL(blkdev_fsync); |
1da177e4 LT |
430 | |
431 | /* | |
432 | * pseudo-fs | |
433 | */ | |
434 | ||
435 | static __cacheline_aligned_in_smp DEFINE_SPINLOCK(bdev_lock); | |
e18b890b | 436 | static struct kmem_cache * bdev_cachep __read_mostly; |
1da177e4 LT |
437 | |
438 | static struct inode *bdev_alloc_inode(struct super_block *sb) | |
439 | { | |
e94b1766 | 440 | struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL); |
1da177e4 LT |
441 | if (!ei) |
442 | return NULL; | |
443 | return &ei->vfs_inode; | |
444 | } | |
445 | ||
446 | static void bdev_destroy_inode(struct inode *inode) | |
447 | { | |
448 | struct bdev_inode *bdi = BDEV_I(inode); | |
449 | ||
1da177e4 LT |
450 | kmem_cache_free(bdev_cachep, bdi); |
451 | } | |
452 | ||
51cc5068 | 453 | static void init_once(void *foo) |
1da177e4 LT |
454 | { |
455 | struct bdev_inode *ei = (struct bdev_inode *) foo; | |
456 | struct block_device *bdev = &ei->bdev; | |
457 | ||
a35afb83 CL |
458 | memset(bdev, 0, sizeof(*bdev)); |
459 | mutex_init(&bdev->bd_mutex); | |
a35afb83 CL |
460 | INIT_LIST_HEAD(&bdev->bd_inodes); |
461 | INIT_LIST_HEAD(&bdev->bd_list); | |
641dc636 | 462 | #ifdef CONFIG_SYSFS |
a35afb83 | 463 | INIT_LIST_HEAD(&bdev->bd_holder_list); |
641dc636 | 464 | #endif |
a35afb83 | 465 | inode_init_once(&ei->vfs_inode); |
fcccf502 TS |
466 | /* Initialize mutex for freeze. */ |
467 | mutex_init(&bdev->bd_fsfreeze_mutex); | |
1da177e4 LT |
468 | } |
469 | ||
470 | static inline void __bd_forget(struct inode *inode) | |
471 | { | |
472 | list_del_init(&inode->i_devices); | |
473 | inode->i_bdev = NULL; | |
474 | inode->i_mapping = &inode->i_data; | |
475 | } | |
476 | ||
477 | static void bdev_clear_inode(struct inode *inode) | |
478 | { | |
479 | struct block_device *bdev = &BDEV_I(inode)->bdev; | |
480 | struct list_head *p; | |
481 | spin_lock(&bdev_lock); | |
482 | while ( (p = bdev->bd_inodes.next) != &bdev->bd_inodes ) { | |
483 | __bd_forget(list_entry(p, struct inode, i_devices)); | |
484 | } | |
485 | list_del_init(&bdev->bd_list); | |
486 | spin_unlock(&bdev_lock); | |
487 | } | |
488 | ||
ee9b6d61 | 489 | static const struct super_operations bdev_sops = { |
1da177e4 LT |
490 | .statfs = simple_statfs, |
491 | .alloc_inode = bdev_alloc_inode, | |
492 | .destroy_inode = bdev_destroy_inode, | |
493 | .drop_inode = generic_delete_inode, | |
494 | .clear_inode = bdev_clear_inode, | |
495 | }; | |
496 | ||
454e2398 DH |
497 | static int bd_get_sb(struct file_system_type *fs_type, |
498 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) | |
1da177e4 | 499 | { |
454e2398 | 500 | return get_sb_pseudo(fs_type, "bdev:", &bdev_sops, 0x62646576, mnt); |
1da177e4 LT |
501 | } |
502 | ||
503 | static struct file_system_type bd_type = { | |
504 | .name = "bdev", | |
505 | .get_sb = bd_get_sb, | |
506 | .kill_sb = kill_anon_super, | |
507 | }; | |
508 | ||
c2acf7b9 | 509 | struct super_block *blockdev_superblock __read_mostly; |
1da177e4 LT |
510 | |
511 | void __init bdev_cache_init(void) | |
512 | { | |
513 | int err; | |
c2acf7b9 DC |
514 | struct vfsmount *bd_mnt; |
515 | ||
1da177e4 | 516 | bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode), |
fffb60f9 PJ |
517 | 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| |
518 | SLAB_MEM_SPREAD|SLAB_PANIC), | |
20c2df83 | 519 | init_once); |
1da177e4 LT |
520 | err = register_filesystem(&bd_type); |
521 | if (err) | |
522 | panic("Cannot register bdev pseudo-fs"); | |
523 | bd_mnt = kern_mount(&bd_type); | |
1da177e4 LT |
524 | if (IS_ERR(bd_mnt)) |
525 | panic("Cannot create bdev pseudo-fs"); | |
2e1483c9 CM |
526 | /* |
527 | * This vfsmount structure is only used to obtain the | |
528 | * blockdev_superblock, so tell kmemleak not to report it. | |
529 | */ | |
530 | kmemleak_not_leak(bd_mnt); | |
1da177e4 LT |
531 | blockdev_superblock = bd_mnt->mnt_sb; /* For writeback */ |
532 | } | |
533 | ||
534 | /* | |
535 | * Most likely _very_ bad one - but then it's hardly critical for small | |
536 | * /dev and can be fixed when somebody will need really large one. | |
537 | * Keep in mind that it will be fed through icache hash function too. | |
538 | */ | |
539 | static inline unsigned long hash(dev_t dev) | |
540 | { | |
541 | return MAJOR(dev)+MINOR(dev); | |
542 | } | |
543 | ||
544 | static int bdev_test(struct inode *inode, void *data) | |
545 | { | |
546 | return BDEV_I(inode)->bdev.bd_dev == *(dev_t *)data; | |
547 | } | |
548 | ||
549 | static int bdev_set(struct inode *inode, void *data) | |
550 | { | |
551 | BDEV_I(inode)->bdev.bd_dev = *(dev_t *)data; | |
552 | return 0; | |
553 | } | |
554 | ||
555 | static LIST_HEAD(all_bdevs); | |
556 | ||
557 | struct block_device *bdget(dev_t dev) | |
558 | { | |
559 | struct block_device *bdev; | |
560 | struct inode *inode; | |
561 | ||
c2acf7b9 | 562 | inode = iget5_locked(blockdev_superblock, hash(dev), |
1da177e4 LT |
563 | bdev_test, bdev_set, &dev); |
564 | ||
565 | if (!inode) | |
566 | return NULL; | |
567 | ||
568 | bdev = &BDEV_I(inode)->bdev; | |
569 | ||
570 | if (inode->i_state & I_NEW) { | |
571 | bdev->bd_contains = NULL; | |
572 | bdev->bd_inode = inode; | |
573 | bdev->bd_block_size = (1 << inode->i_blkbits); | |
574 | bdev->bd_part_count = 0; | |
575 | bdev->bd_invalidated = 0; | |
576 | inode->i_mode = S_IFBLK; | |
577 | inode->i_rdev = dev; | |
578 | inode->i_bdev = bdev; | |
579 | inode->i_data.a_ops = &def_blk_aops; | |
580 | mapping_set_gfp_mask(&inode->i_data, GFP_USER); | |
581 | inode->i_data.backing_dev_info = &default_backing_dev_info; | |
582 | spin_lock(&bdev_lock); | |
583 | list_add(&bdev->bd_list, &all_bdevs); | |
584 | spin_unlock(&bdev_lock); | |
585 | unlock_new_inode(inode); | |
586 | } | |
587 | return bdev; | |
588 | } | |
589 | ||
590 | EXPORT_SYMBOL(bdget); | |
591 | ||
dddac6a7 AJ |
592 | /** |
593 | * bdgrab -- Grab a reference to an already referenced block device | |
594 | * @bdev: Block device to grab a reference to. | |
595 | */ | |
596 | struct block_device *bdgrab(struct block_device *bdev) | |
597 | { | |
598 | atomic_inc(&bdev->bd_inode->i_count); | |
599 | return bdev; | |
600 | } | |
601 | ||
1da177e4 LT |
602 | long nr_blockdev_pages(void) |
603 | { | |
203a2935 | 604 | struct block_device *bdev; |
1da177e4 LT |
605 | long ret = 0; |
606 | spin_lock(&bdev_lock); | |
203a2935 | 607 | list_for_each_entry(bdev, &all_bdevs, bd_list) { |
1da177e4 LT |
608 | ret += bdev->bd_inode->i_mapping->nrpages; |
609 | } | |
610 | spin_unlock(&bdev_lock); | |
611 | return ret; | |
612 | } | |
613 | ||
614 | void bdput(struct block_device *bdev) | |
615 | { | |
616 | iput(bdev->bd_inode); | |
617 | } | |
618 | ||
619 | EXPORT_SYMBOL(bdput); | |
620 | ||
621 | static struct block_device *bd_acquire(struct inode *inode) | |
622 | { | |
623 | struct block_device *bdev; | |
09d967c6 | 624 | |
1da177e4 LT |
625 | spin_lock(&bdev_lock); |
626 | bdev = inode->i_bdev; | |
09d967c6 OH |
627 | if (bdev) { |
628 | atomic_inc(&bdev->bd_inode->i_count); | |
1da177e4 LT |
629 | spin_unlock(&bdev_lock); |
630 | return bdev; | |
631 | } | |
632 | spin_unlock(&bdev_lock); | |
09d967c6 | 633 | |
1da177e4 LT |
634 | bdev = bdget(inode->i_rdev); |
635 | if (bdev) { | |
636 | spin_lock(&bdev_lock); | |
09d967c6 OH |
637 | if (!inode->i_bdev) { |
638 | /* | |
639 | * We take an additional bd_inode->i_count for inode, | |
640 | * and it's released in clear_inode() of inode. | |
641 | * So, we can access it via ->i_mapping always | |
642 | * without igrab(). | |
643 | */ | |
644 | atomic_inc(&bdev->bd_inode->i_count); | |
645 | inode->i_bdev = bdev; | |
646 | inode->i_mapping = bdev->bd_inode->i_mapping; | |
647 | list_add(&inode->i_devices, &bdev->bd_inodes); | |
648 | } | |
1da177e4 LT |
649 | spin_unlock(&bdev_lock); |
650 | } | |
651 | return bdev; | |
652 | } | |
653 | ||
654 | /* Call when you free inode */ | |
655 | ||
656 | void bd_forget(struct inode *inode) | |
657 | { | |
09d967c6 OH |
658 | struct block_device *bdev = NULL; |
659 | ||
1da177e4 | 660 | spin_lock(&bdev_lock); |
09d967c6 | 661 | if (inode->i_bdev) { |
c2acf7b9 | 662 | if (!sb_is_blkdev_sb(inode->i_sb)) |
09d967c6 | 663 | bdev = inode->i_bdev; |
1da177e4 | 664 | __bd_forget(inode); |
09d967c6 | 665 | } |
1da177e4 | 666 | spin_unlock(&bdev_lock); |
09d967c6 OH |
667 | |
668 | if (bdev) | |
669 | iput(bdev->bd_inode); | |
1da177e4 LT |
670 | } |
671 | ||
672 | int bd_claim(struct block_device *bdev, void *holder) | |
673 | { | |
674 | int res; | |
675 | spin_lock(&bdev_lock); | |
676 | ||
677 | /* first decide result */ | |
678 | if (bdev->bd_holder == holder) | |
679 | res = 0; /* already a holder */ | |
680 | else if (bdev->bd_holder != NULL) | |
681 | res = -EBUSY; /* held by someone else */ | |
682 | else if (bdev->bd_contains == bdev) | |
683 | res = 0; /* is a whole device which isn't held */ | |
684 | ||
685 | else if (bdev->bd_contains->bd_holder == bd_claim) | |
686 | res = 0; /* is a partition of a device that is being partitioned */ | |
687 | else if (bdev->bd_contains->bd_holder != NULL) | |
688 | res = -EBUSY; /* is a partition of a held device */ | |
689 | else | |
690 | res = 0; /* is a partition of an un-held device */ | |
691 | ||
692 | /* now impose change */ | |
693 | if (res==0) { | |
694 | /* note that for a whole device bd_holders | |
695 | * will be incremented twice, and bd_holder will | |
696 | * be set to bd_claim before being set to holder | |
697 | */ | |
698 | bdev->bd_contains->bd_holders ++; | |
699 | bdev->bd_contains->bd_holder = bd_claim; | |
700 | bdev->bd_holders++; | |
701 | bdev->bd_holder = holder; | |
702 | } | |
703 | spin_unlock(&bdev_lock); | |
704 | return res; | |
705 | } | |
706 | ||
707 | EXPORT_SYMBOL(bd_claim); | |
708 | ||
709 | void bd_release(struct block_device *bdev) | |
710 | { | |
711 | spin_lock(&bdev_lock); | |
712 | if (!--bdev->bd_contains->bd_holders) | |
713 | bdev->bd_contains->bd_holder = NULL; | |
714 | if (!--bdev->bd_holders) | |
715 | bdev->bd_holder = NULL; | |
716 | spin_unlock(&bdev_lock); | |
717 | } | |
718 | ||
719 | EXPORT_SYMBOL(bd_release); | |
720 | ||
641dc636 JN |
721 | #ifdef CONFIG_SYSFS |
722 | /* | |
723 | * Functions for bd_claim_by_kobject / bd_release_from_kobject | |
724 | * | |
725 | * If a kobject is passed to bd_claim_by_kobject() | |
726 | * and the kobject has a parent directory, | |
727 | * following symlinks are created: | |
728 | * o from the kobject to the claimed bdev | |
729 | * o from "holders" directory of the bdev to the parent of the kobject | |
730 | * bd_release_from_kobject() removes these symlinks. | |
731 | * | |
732 | * Example: | |
733 | * If /dev/dm-0 maps to /dev/sda, kobject corresponding to | |
734 | * /sys/block/dm-0/slaves is passed to bd_claim_by_kobject(), then: | |
735 | * /sys/block/dm-0/slaves/sda --> /sys/block/sda | |
736 | * /sys/block/sda/holders/dm-0 --> /sys/block/dm-0 | |
737 | */ | |
738 | ||
4d7dd8fd | 739 | static int add_symlink(struct kobject *from, struct kobject *to) |
641dc636 JN |
740 | { |
741 | if (!from || !to) | |
4d7dd8fd AM |
742 | return 0; |
743 | return sysfs_create_link(from, to, kobject_name(to)); | |
641dc636 JN |
744 | } |
745 | ||
746 | static void del_symlink(struct kobject *from, struct kobject *to) | |
747 | { | |
748 | if (!from || !to) | |
749 | return; | |
750 | sysfs_remove_link(from, kobject_name(to)); | |
751 | } | |
752 | ||
753 | /* | |
754 | * 'struct bd_holder' contains pointers to kobjects symlinked by | |
755 | * bd_claim_by_kobject. | |
756 | * It's connected to bd_holder_list which is protected by bdev->bd_sem. | |
757 | */ | |
758 | struct bd_holder { | |
759 | struct list_head list; /* chain of holders of the bdev */ | |
760 | int count; /* references from the holder */ | |
761 | struct kobject *sdir; /* holder object, e.g. "/block/dm-0/slaves" */ | |
762 | struct kobject *hdev; /* e.g. "/block/dm-0" */ | |
763 | struct kobject *hdir; /* e.g. "/block/sda/holders" */ | |
764 | struct kobject *sdev; /* e.g. "/block/sda" */ | |
765 | }; | |
766 | ||
767 | /* | |
768 | * Get references of related kobjects at once. | |
769 | * Returns 1 on success. 0 on failure. | |
770 | * | |
771 | * Should call bd_holder_release_dirs() after successful use. | |
772 | */ | |
773 | static int bd_holder_grab_dirs(struct block_device *bdev, | |
774 | struct bd_holder *bo) | |
775 | { | |
776 | if (!bdev || !bo) | |
777 | return 0; | |
778 | ||
779 | bo->sdir = kobject_get(bo->sdir); | |
780 | if (!bo->sdir) | |
781 | return 0; | |
782 | ||
783 | bo->hdev = kobject_get(bo->sdir->parent); | |
784 | if (!bo->hdev) | |
785 | goto fail_put_sdir; | |
786 | ||
0762b8bd | 787 | bo->sdev = kobject_get(&part_to_dev(bdev->bd_part)->kobj); |
641dc636 JN |
788 | if (!bo->sdev) |
789 | goto fail_put_hdev; | |
790 | ||
4c46501d | 791 | bo->hdir = kobject_get(bdev->bd_part->holder_dir); |
641dc636 JN |
792 | if (!bo->hdir) |
793 | goto fail_put_sdev; | |
794 | ||
795 | return 1; | |
796 | ||
797 | fail_put_sdev: | |
798 | kobject_put(bo->sdev); | |
799 | fail_put_hdev: | |
800 | kobject_put(bo->hdev); | |
801 | fail_put_sdir: | |
802 | kobject_put(bo->sdir); | |
803 | ||
804 | return 0; | |
805 | } | |
806 | ||
807 | /* Put references of related kobjects at once. */ | |
808 | static void bd_holder_release_dirs(struct bd_holder *bo) | |
809 | { | |
810 | kobject_put(bo->hdir); | |
811 | kobject_put(bo->sdev); | |
812 | kobject_put(bo->hdev); | |
813 | kobject_put(bo->sdir); | |
814 | } | |
815 | ||
816 | static struct bd_holder *alloc_bd_holder(struct kobject *kobj) | |
817 | { | |
818 | struct bd_holder *bo; | |
819 | ||
820 | bo = kzalloc(sizeof(*bo), GFP_KERNEL); | |
821 | if (!bo) | |
822 | return NULL; | |
823 | ||
824 | bo->count = 1; | |
825 | bo->sdir = kobj; | |
826 | ||
827 | return bo; | |
828 | } | |
829 | ||
830 | static void free_bd_holder(struct bd_holder *bo) | |
831 | { | |
832 | kfree(bo); | |
833 | } | |
834 | ||
df6c0cd9 JN |
835 | /** |
836 | * find_bd_holder - find matching struct bd_holder from the block device | |
837 | * | |
838 | * @bdev: struct block device to be searched | |
839 | * @bo: target struct bd_holder | |
840 | * | |
841 | * Returns matching entry with @bo in @bdev->bd_holder_list. | |
842 | * If found, increment the reference count and return the pointer. | |
843 | * If not found, returns NULL. | |
844 | */ | |
36a561d6 AM |
845 | static struct bd_holder *find_bd_holder(struct block_device *bdev, |
846 | struct bd_holder *bo) | |
df6c0cd9 JN |
847 | { |
848 | struct bd_holder *tmp; | |
849 | ||
850 | list_for_each_entry(tmp, &bdev->bd_holder_list, list) | |
851 | if (tmp->sdir == bo->sdir) { | |
852 | tmp->count++; | |
853 | return tmp; | |
854 | } | |
855 | ||
856 | return NULL; | |
857 | } | |
858 | ||
641dc636 JN |
859 | /** |
860 | * add_bd_holder - create sysfs symlinks for bd_claim() relationship | |
861 | * | |
862 | * @bdev: block device to be bd_claimed | |
863 | * @bo: preallocated and initialized by alloc_bd_holder() | |
864 | * | |
df6c0cd9 | 865 | * Add @bo to @bdev->bd_holder_list, create symlinks. |
641dc636 | 866 | * |
df6c0cd9 JN |
867 | * Returns 0 if symlinks are created. |
868 | * Returns -ve if something fails. | |
641dc636 JN |
869 | */ |
870 | static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo) | |
871 | { | |
4e91672c | 872 | int err; |
641dc636 JN |
873 | |
874 | if (!bo) | |
4d7dd8fd | 875 | return -EINVAL; |
641dc636 | 876 | |
641dc636 | 877 | if (!bd_holder_grab_dirs(bdev, bo)) |
4d7dd8fd | 878 | return -EBUSY; |
641dc636 | 879 | |
4e91672c JW |
880 | err = add_symlink(bo->sdir, bo->sdev); |
881 | if (err) | |
882 | return err; | |
883 | ||
884 | err = add_symlink(bo->hdir, bo->hdev); | |
885 | if (err) { | |
886 | del_symlink(bo->sdir, bo->sdev); | |
887 | return err; | |
4d7dd8fd | 888 | } |
4e91672c JW |
889 | |
890 | list_add_tail(&bo->list, &bdev->bd_holder_list); | |
891 | return 0; | |
641dc636 JN |
892 | } |
893 | ||
894 | /** | |
895 | * del_bd_holder - delete sysfs symlinks for bd_claim() relationship | |
896 | * | |
897 | * @bdev: block device to be bd_claimed | |
898 | * @kobj: holder's kobject | |
899 | * | |
900 | * If there is matching entry with @kobj in @bdev->bd_holder_list | |
901 | * and no other bd_claim() from the same kobject, | |
902 | * remove the struct bd_holder from the list, delete symlinks for it. | |
903 | * | |
904 | * Returns a pointer to the struct bd_holder when it's removed from the list | |
905 | * and ready to be freed. | |
906 | * Returns NULL if matching claim isn't found or there is other bd_claim() | |
907 | * by the same kobject. | |
908 | */ | |
909 | static struct bd_holder *del_bd_holder(struct block_device *bdev, | |
910 | struct kobject *kobj) | |
911 | { | |
912 | struct bd_holder *bo; | |
913 | ||
914 | list_for_each_entry(bo, &bdev->bd_holder_list, list) { | |
915 | if (bo->sdir == kobj) { | |
916 | bo->count--; | |
917 | BUG_ON(bo->count < 0); | |
918 | if (!bo->count) { | |
919 | list_del(&bo->list); | |
920 | del_symlink(bo->sdir, bo->sdev); | |
921 | del_symlink(bo->hdir, bo->hdev); | |
922 | bd_holder_release_dirs(bo); | |
923 | return bo; | |
924 | } | |
925 | break; | |
926 | } | |
927 | } | |
928 | ||
929 | return NULL; | |
930 | } | |
931 | ||
932 | /** | |
933 | * bd_claim_by_kobject - bd_claim() with additional kobject signature | |
934 | * | |
935 | * @bdev: block device to be claimed | |
936 | * @holder: holder's signature | |
937 | * @kobj: holder's kobject | |
938 | * | |
939 | * Do bd_claim() and if it succeeds, create sysfs symlinks between | |
940 | * the bdev and the holder's kobject. | |
941 | * Use bd_release_from_kobject() when relesing the claimed bdev. | |
942 | * | |
943 | * Returns 0 on success. (same as bd_claim()) | |
944 | * Returns errno on failure. | |
945 | */ | |
946 | static int bd_claim_by_kobject(struct block_device *bdev, void *holder, | |
947 | struct kobject *kobj) | |
948 | { | |
4e91672c | 949 | int err; |
df6c0cd9 | 950 | struct bd_holder *bo, *found; |
641dc636 JN |
951 | |
952 | if (!kobj) | |
953 | return -EINVAL; | |
954 | ||
955 | bo = alloc_bd_holder(kobj); | |
956 | if (!bo) | |
957 | return -ENOMEM; | |
958 | ||
2e7b651d | 959 | mutex_lock(&bdev->bd_mutex); |
df6c0cd9 | 960 | |
4e91672c JW |
961 | err = bd_claim(bdev, holder); |
962 | if (err) | |
4210df28 | 963 | goto fail; |
4e91672c JW |
964 | |
965 | found = find_bd_holder(bdev, bo); | |
966 | if (found) | |
4210df28 | 967 | goto fail; |
4e91672c JW |
968 | |
969 | err = add_bd_holder(bdev, bo); | |
970 | if (err) | |
971 | bd_release(bdev); | |
4210df28 AM |
972 | else |
973 | bo = NULL; | |
974 | fail: | |
b4cf1b72 | 975 | mutex_unlock(&bdev->bd_mutex); |
4210df28 | 976 | free_bd_holder(bo); |
4e91672c | 977 | return err; |
641dc636 JN |
978 | } |
979 | ||
980 | /** | |
981 | * bd_release_from_kobject - bd_release() with additional kobject signature | |
982 | * | |
983 | * @bdev: block device to be released | |
984 | * @kobj: holder's kobject | |
985 | * | |
986 | * Do bd_release() and remove sysfs symlinks created by bd_claim_by_kobject(). | |
987 | */ | |
988 | static void bd_release_from_kobject(struct block_device *bdev, | |
989 | struct kobject *kobj) | |
990 | { | |
641dc636 JN |
991 | if (!kobj) |
992 | return; | |
993 | ||
2e7b651d | 994 | mutex_lock(&bdev->bd_mutex); |
641dc636 | 995 | bd_release(bdev); |
4210df28 | 996 | free_bd_holder(del_bd_holder(bdev, kobj)); |
b4cf1b72 | 997 | mutex_unlock(&bdev->bd_mutex); |
641dc636 JN |
998 | } |
999 | ||
1000 | /** | |
1001 | * bd_claim_by_disk - wrapper function for bd_claim_by_kobject() | |
1002 | * | |
1003 | * @bdev: block device to be claimed | |
1004 | * @holder: holder's signature | |
1005 | * @disk: holder's gendisk | |
1006 | * | |
1007 | * Call bd_claim_by_kobject() with getting @disk->slave_dir. | |
1008 | */ | |
1009 | int bd_claim_by_disk(struct block_device *bdev, void *holder, | |
1010 | struct gendisk *disk) | |
1011 | { | |
1012 | return bd_claim_by_kobject(bdev, holder, kobject_get(disk->slave_dir)); | |
1013 | } | |
1014 | EXPORT_SYMBOL_GPL(bd_claim_by_disk); | |
1015 | ||
1016 | /** | |
1017 | * bd_release_from_disk - wrapper function for bd_release_from_kobject() | |
1018 | * | |
1019 | * @bdev: block device to be claimed | |
1020 | * @disk: holder's gendisk | |
1021 | * | |
1022 | * Call bd_release_from_kobject() and put @disk->slave_dir. | |
1023 | */ | |
1024 | void bd_release_from_disk(struct block_device *bdev, struct gendisk *disk) | |
1025 | { | |
1026 | bd_release_from_kobject(bdev, disk->slave_dir); | |
1027 | kobject_put(disk->slave_dir); | |
1028 | } | |
1029 | EXPORT_SYMBOL_GPL(bd_release_from_disk); | |
1030 | #endif | |
1031 | ||
1da177e4 LT |
1032 | /* |
1033 | * Tries to open block device by device number. Use it ONLY if you | |
1034 | * really do not have anything better - i.e. when you are behind a | |
1035 | * truly sucky interface and all you are given is a device number. _Never_ | |
1036 | * to be used for internal purposes. If you ever need it - reconsider | |
1037 | * your API. | |
1038 | */ | |
aeb5d727 | 1039 | struct block_device *open_by_devnum(dev_t dev, fmode_t mode) |
1da177e4 LT |
1040 | { |
1041 | struct block_device *bdev = bdget(dev); | |
1042 | int err = -ENOMEM; | |
1da177e4 | 1043 | if (bdev) |
572c4892 | 1044 | err = blkdev_get(bdev, mode); |
1da177e4 LT |
1045 | return err ? ERR_PTR(err) : bdev; |
1046 | } | |
1047 | ||
1048 | EXPORT_SYMBOL(open_by_devnum); | |
1049 | ||
56ade44b AP |
1050 | /** |
1051 | * flush_disk - invalidates all buffer-cache entries on a disk | |
1052 | * | |
1053 | * @bdev: struct block device to be flushed | |
1054 | * | |
1055 | * Invalidates all buffer-cache entries on a disk. It should be called | |
1056 | * when a disk has been changed -- either by a media change or online | |
1057 | * resize. | |
1058 | */ | |
1059 | static void flush_disk(struct block_device *bdev) | |
1060 | { | |
1061 | if (__invalidate_device(bdev)) { | |
1062 | char name[BDEVNAME_SIZE] = ""; | |
1063 | ||
1064 | if (bdev->bd_disk) | |
1065 | disk_name(bdev->bd_disk, 0, name); | |
1066 | printk(KERN_WARNING "VFS: busy inodes on changed media or " | |
1067 | "resized disk %s\n", name); | |
1068 | } | |
1069 | ||
1070 | if (!bdev->bd_disk) | |
1071 | return; | |
1072 | if (disk_partitionable(bdev->bd_disk)) | |
1073 | bdev->bd_invalidated = 1; | |
1074 | } | |
1075 | ||
c3279d14 | 1076 | /** |
57d1b536 | 1077 | * check_disk_size_change - checks for disk size change and adjusts bdev size. |
c3279d14 AP |
1078 | * @disk: struct gendisk to check |
1079 | * @bdev: struct bdev to adjust. | |
1080 | * | |
1081 | * This routine checks to see if the bdev size does not match the disk size | |
1082 | * and adjusts it if it differs. | |
1083 | */ | |
1084 | void check_disk_size_change(struct gendisk *disk, struct block_device *bdev) | |
1085 | { | |
1086 | loff_t disk_size, bdev_size; | |
1087 | ||
1088 | disk_size = (loff_t)get_capacity(disk) << 9; | |
1089 | bdev_size = i_size_read(bdev->bd_inode); | |
1090 | if (disk_size != bdev_size) { | |
1091 | char name[BDEVNAME_SIZE]; | |
1092 | ||
1093 | disk_name(disk, 0, name); | |
1094 | printk(KERN_INFO | |
1095 | "%s: detected capacity change from %lld to %lld\n", | |
1096 | name, bdev_size, disk_size); | |
1097 | i_size_write(bdev->bd_inode, disk_size); | |
608aeef1 | 1098 | flush_disk(bdev); |
c3279d14 AP |
1099 | } |
1100 | } | |
1101 | EXPORT_SYMBOL(check_disk_size_change); | |
1102 | ||
0c002c2f | 1103 | /** |
57d1b536 | 1104 | * revalidate_disk - wrapper for lower-level driver's revalidate_disk call-back |
0c002c2f AP |
1105 | * @disk: struct gendisk to be revalidated |
1106 | * | |
1107 | * This routine is a wrapper for lower-level driver's revalidate_disk | |
1108 | * call-backs. It is used to do common pre and post operations needed | |
1109 | * for all revalidate_disk operations. | |
1110 | */ | |
1111 | int revalidate_disk(struct gendisk *disk) | |
1112 | { | |
c3279d14 | 1113 | struct block_device *bdev; |
0c002c2f AP |
1114 | int ret = 0; |
1115 | ||
1116 | if (disk->fops->revalidate_disk) | |
1117 | ret = disk->fops->revalidate_disk(disk); | |
1118 | ||
c3279d14 AP |
1119 | bdev = bdget_disk(disk, 0); |
1120 | if (!bdev) | |
1121 | return ret; | |
1122 | ||
1123 | mutex_lock(&bdev->bd_mutex); | |
1124 | check_disk_size_change(disk, bdev); | |
1125 | mutex_unlock(&bdev->bd_mutex); | |
1126 | bdput(bdev); | |
0c002c2f AP |
1127 | return ret; |
1128 | } | |
1129 | EXPORT_SYMBOL(revalidate_disk); | |
1130 | ||
1da177e4 LT |
1131 | /* |
1132 | * This routine checks whether a removable media has been changed, | |
1133 | * and invalidates all buffer-cache-entries in that case. This | |
1134 | * is a relatively slow routine, so we have to try to minimize using | |
1135 | * it. Thus it is called only upon a 'mount' or 'open'. This | |
1136 | * is the best way of combining speed and utility, I think. | |
1137 | * People changing diskettes in the middle of an operation deserve | |
1138 | * to lose :-) | |
1139 | */ | |
1140 | int check_disk_change(struct block_device *bdev) | |
1141 | { | |
1142 | struct gendisk *disk = bdev->bd_disk; | |
83d5cde4 | 1143 | const struct block_device_operations *bdops = disk->fops; |
1da177e4 LT |
1144 | |
1145 | if (!bdops->media_changed) | |
1146 | return 0; | |
1147 | if (!bdops->media_changed(bdev->bd_disk)) | |
1148 | return 0; | |
1149 | ||
56ade44b | 1150 | flush_disk(bdev); |
1da177e4 LT |
1151 | if (bdops->revalidate_disk) |
1152 | bdops->revalidate_disk(bdev->bd_disk); | |
1da177e4 LT |
1153 | return 1; |
1154 | } | |
1155 | ||
1156 | EXPORT_SYMBOL(check_disk_change); | |
1157 | ||
1158 | void bd_set_size(struct block_device *bdev, loff_t size) | |
1159 | { | |
e1defc4f | 1160 | unsigned bsize = bdev_logical_block_size(bdev); |
1da177e4 LT |
1161 | |
1162 | bdev->bd_inode->i_size = size; | |
1163 | while (bsize < PAGE_CACHE_SIZE) { | |
1164 | if (size & bsize) | |
1165 | break; | |
1166 | bsize <<= 1; | |
1167 | } | |
1168 | bdev->bd_block_size = bsize; | |
1169 | bdev->bd_inode->i_blkbits = blksize_bits(bsize); | |
1170 | } | |
1171 | EXPORT_SYMBOL(bd_set_size); | |
1172 | ||
9a1c3542 | 1173 | static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part); |
37be4124 | 1174 | |
6d740cd5 PZ |
1175 | /* |
1176 | * bd_mutex locking: | |
1177 | * | |
1178 | * mutex_lock(part->bd_mutex) | |
1179 | * mutex_lock_nested(whole->bd_mutex, 1) | |
1180 | */ | |
1181 | ||
572c4892 | 1182 | static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) |
1da177e4 | 1183 | { |
1da177e4 | 1184 | struct gendisk *disk; |
7db9cfd3 | 1185 | int ret; |
cf771cb5 | 1186 | int partno; |
fe6e9c1f AV |
1187 | int perm = 0; |
1188 | ||
572c4892 | 1189 | if (mode & FMODE_READ) |
fe6e9c1f | 1190 | perm |= MAY_READ; |
572c4892 | 1191 | if (mode & FMODE_WRITE) |
fe6e9c1f AV |
1192 | perm |= MAY_WRITE; |
1193 | /* | |
1194 | * hooks: /n/, see "layering violations". | |
1195 | */ | |
1196 | ret = devcgroup_inode_permission(bdev->bd_inode, perm); | |
82666020 AV |
1197 | if (ret != 0) { |
1198 | bdput(bdev); | |
7db9cfd3 | 1199 | return ret; |
82666020 | 1200 | } |
7db9cfd3 | 1201 | |
1da177e4 | 1202 | lock_kernel(); |
d3374825 | 1203 | restart: |
0762b8bd | 1204 | |
89f97496 | 1205 | ret = -ENXIO; |
cf771cb5 | 1206 | disk = get_gendisk(bdev->bd_dev, &partno); |
0762b8bd TH |
1207 | if (!disk) |
1208 | goto out_unlock_kernel; | |
1da177e4 | 1209 | |
6796bf54 | 1210 | mutex_lock_nested(&bdev->bd_mutex, for_part); |
1da177e4 LT |
1211 | if (!bdev->bd_openers) { |
1212 | bdev->bd_disk = disk; | |
1213 | bdev->bd_contains = bdev; | |
cf771cb5 | 1214 | if (!partno) { |
1da177e4 | 1215 | struct backing_dev_info *bdi; |
89f97496 TH |
1216 | |
1217 | ret = -ENXIO; | |
1218 | bdev->bd_part = disk_get_part(disk, partno); | |
1219 | if (!bdev->bd_part) | |
1220 | goto out_clear; | |
1221 | ||
1da177e4 | 1222 | if (disk->fops->open) { |
572c4892 | 1223 | ret = disk->fops->open(bdev, mode); |
d3374825 N |
1224 | if (ret == -ERESTARTSYS) { |
1225 | /* Lost a race with 'disk' being | |
1226 | * deleted, try again. | |
1227 | * See md.c | |
1228 | */ | |
1229 | disk_put_part(bdev->bd_part); | |
1230 | bdev->bd_part = NULL; | |
1231 | module_put(disk->fops->owner); | |
1232 | put_disk(disk); | |
1233 | bdev->bd_disk = NULL; | |
1234 | mutex_unlock(&bdev->bd_mutex); | |
1235 | goto restart; | |
1236 | } | |
1da177e4 | 1237 | if (ret) |
0762b8bd | 1238 | goto out_clear; |
1da177e4 LT |
1239 | } |
1240 | if (!bdev->bd_openers) { | |
1241 | bd_set_size(bdev,(loff_t)get_capacity(disk)<<9); | |
1242 | bdi = blk_get_backing_dev_info(bdev); | |
1243 | if (bdi == NULL) | |
1244 | bdi = &default_backing_dev_info; | |
1245 | bdev->bd_inode->i_data.backing_dev_info = bdi; | |
1246 | } | |
1247 | if (bdev->bd_invalidated) | |
1248 | rescan_partitions(disk, bdev); | |
1249 | } else { | |
1da177e4 LT |
1250 | struct block_device *whole; |
1251 | whole = bdget_disk(disk, 0); | |
1252 | ret = -ENOMEM; | |
1253 | if (!whole) | |
0762b8bd | 1254 | goto out_clear; |
37be4124 | 1255 | BUG_ON(for_part); |
572c4892 | 1256 | ret = __blkdev_get(whole, mode, 1); |
1da177e4 | 1257 | if (ret) |
0762b8bd | 1258 | goto out_clear; |
1da177e4 | 1259 | bdev->bd_contains = whole; |
1da177e4 LT |
1260 | bdev->bd_inode->i_data.backing_dev_info = |
1261 | whole->bd_inode->i_data.backing_dev_info; | |
89f97496 | 1262 | bdev->bd_part = disk_get_part(disk, partno); |
e71bf0d0 | 1263 | if (!(disk->flags & GENHD_FL_UP) || |
89f97496 | 1264 | !bdev->bd_part || !bdev->bd_part->nr_sects) { |
1da177e4 | 1265 | ret = -ENXIO; |
0762b8bd | 1266 | goto out_clear; |
1da177e4 | 1267 | } |
89f97496 | 1268 | bd_set_size(bdev, (loff_t)bdev->bd_part->nr_sects << 9); |
1da177e4 LT |
1269 | } |
1270 | } else { | |
0762b8bd | 1271 | module_put(disk->fops->owner); |
960cc0f4 | 1272 | put_disk(disk); |
0762b8bd | 1273 | disk = NULL; |
1da177e4 LT |
1274 | if (bdev->bd_contains == bdev) { |
1275 | if (bdev->bd_disk->fops->open) { | |
572c4892 | 1276 | ret = bdev->bd_disk->fops->open(bdev, mode); |
1da177e4 | 1277 | if (ret) |
0762b8bd | 1278 | goto out_unlock_bdev; |
1da177e4 LT |
1279 | } |
1280 | if (bdev->bd_invalidated) | |
1281 | rescan_partitions(bdev->bd_disk, bdev); | |
1da177e4 LT |
1282 | } |
1283 | } | |
1284 | bdev->bd_openers++; | |
37be4124 N |
1285 | if (for_part) |
1286 | bdev->bd_part_count++; | |
c039e313 | 1287 | mutex_unlock(&bdev->bd_mutex); |
1da177e4 LT |
1288 | unlock_kernel(); |
1289 | return 0; | |
1290 | ||
0762b8bd | 1291 | out_clear: |
89f97496 | 1292 | disk_put_part(bdev->bd_part); |
1da177e4 | 1293 | bdev->bd_disk = NULL; |
0762b8bd | 1294 | bdev->bd_part = NULL; |
1da177e4 LT |
1295 | bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info; |
1296 | if (bdev != bdev->bd_contains) | |
572c4892 | 1297 | __blkdev_put(bdev->bd_contains, mode, 1); |
1da177e4 | 1298 | bdev->bd_contains = NULL; |
0762b8bd | 1299 | out_unlock_bdev: |
c039e313 | 1300 | mutex_unlock(&bdev->bd_mutex); |
0762b8bd | 1301 | out_unlock_kernel: |
1da177e4 | 1302 | unlock_kernel(); |
0762b8bd | 1303 | |
0762b8bd TH |
1304 | if (disk) |
1305 | module_put(disk->fops->owner); | |
1306 | put_disk(disk); | |
1307 | bdput(bdev); | |
1308 | ||
1da177e4 LT |
1309 | return ret; |
1310 | } | |
1311 | ||
572c4892 | 1312 | int blkdev_get(struct block_device *bdev, fmode_t mode) |
1da177e4 | 1313 | { |
572c4892 | 1314 | return __blkdev_get(bdev, mode, 0); |
37be4124 | 1315 | } |
1da177e4 LT |
1316 | EXPORT_SYMBOL(blkdev_get); |
1317 | ||
1318 | static int blkdev_open(struct inode * inode, struct file * filp) | |
1319 | { | |
1320 | struct block_device *bdev; | |
1321 | int res; | |
1322 | ||
1323 | /* | |
1324 | * Preserve backwards compatibility and allow large file access | |
1325 | * even if userspace doesn't ask for it explicitly. Some mkfs | |
1326 | * binary needs it. We might want to drop this workaround | |
1327 | * during an unstable branch. | |
1328 | */ | |
1329 | filp->f_flags |= O_LARGEFILE; | |
1330 | ||
572c4892 AV |
1331 | if (filp->f_flags & O_NDELAY) |
1332 | filp->f_mode |= FMODE_NDELAY; | |
1333 | if (filp->f_flags & O_EXCL) | |
1334 | filp->f_mode |= FMODE_EXCL; | |
1335 | if ((filp->f_flags & O_ACCMODE) == 3) | |
1336 | filp->f_mode |= FMODE_WRITE_IOCTL; | |
1337 | ||
1da177e4 | 1338 | bdev = bd_acquire(inode); |
6a2aae06 PE |
1339 | if (bdev == NULL) |
1340 | return -ENOMEM; | |
1da177e4 | 1341 | |
572c4892 AV |
1342 | filp->f_mapping = bdev->bd_inode->i_mapping; |
1343 | ||
1344 | res = blkdev_get(bdev, filp->f_mode); | |
1da177e4 LT |
1345 | if (res) |
1346 | return res; | |
1347 | ||
ebbefc01 CH |
1348 | if (filp->f_mode & FMODE_EXCL) { |
1349 | res = bd_claim(bdev, filp); | |
1350 | if (res) | |
1351 | goto out_blkdev_put; | |
1352 | } | |
1da177e4 | 1353 | |
ebbefc01 | 1354 | return 0; |
1da177e4 | 1355 | |
ebbefc01 | 1356 | out_blkdev_put: |
9a1c3542 | 1357 | blkdev_put(bdev, filp->f_mode); |
1da177e4 LT |
1358 | return res; |
1359 | } | |
1360 | ||
9a1c3542 | 1361 | static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part) |
2e7b651d PZ |
1362 | { |
1363 | int ret = 0; | |
2e7b651d | 1364 | struct gendisk *disk = bdev->bd_disk; |
37be4124 | 1365 | struct block_device *victim = NULL; |
2e7b651d | 1366 | |
6796bf54 | 1367 | mutex_lock_nested(&bdev->bd_mutex, for_part); |
2e7b651d | 1368 | lock_kernel(); |
37be4124 N |
1369 | if (for_part) |
1370 | bdev->bd_part_count--; | |
1371 | ||
2e7b651d PZ |
1372 | if (!--bdev->bd_openers) { |
1373 | sync_blockdev(bdev); | |
1374 | kill_bdev(bdev); | |
1375 | } | |
1376 | if (bdev->bd_contains == bdev) { | |
1377 | if (disk->fops->release) | |
9a1c3542 | 1378 | ret = disk->fops->release(disk, mode); |
2e7b651d PZ |
1379 | } |
1380 | if (!bdev->bd_openers) { | |
1381 | struct module *owner = disk->fops->owner; | |
1382 | ||
1383 | put_disk(disk); | |
1384 | module_put(owner); | |
0762b8bd TH |
1385 | disk_put_part(bdev->bd_part); |
1386 | bdev->bd_part = NULL; | |
2e7b651d PZ |
1387 | bdev->bd_disk = NULL; |
1388 | bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info; | |
37be4124 N |
1389 | if (bdev != bdev->bd_contains) |
1390 | victim = bdev->bd_contains; | |
2e7b651d PZ |
1391 | bdev->bd_contains = NULL; |
1392 | } | |
1393 | unlock_kernel(); | |
1394 | mutex_unlock(&bdev->bd_mutex); | |
1395 | bdput(bdev); | |
37be4124 | 1396 | if (victim) |
9a1c3542 | 1397 | __blkdev_put(victim, mode, 1); |
2e7b651d PZ |
1398 | return ret; |
1399 | } | |
1400 | ||
9a1c3542 | 1401 | int blkdev_put(struct block_device *bdev, fmode_t mode) |
37be4124 | 1402 | { |
9a1c3542 | 1403 | return __blkdev_put(bdev, mode, 0); |
37be4124 | 1404 | } |
2e7b651d PZ |
1405 | EXPORT_SYMBOL(blkdev_put); |
1406 | ||
1da177e4 LT |
1407 | static int blkdev_close(struct inode * inode, struct file * filp) |
1408 | { | |
1409 | struct block_device *bdev = I_BDEV(filp->f_mapping->host); | |
1410 | if (bdev->bd_holder == filp) | |
1411 | bd_release(bdev); | |
9a1c3542 | 1412 | return blkdev_put(bdev, filp->f_mode); |
1da177e4 LT |
1413 | } |
1414 | ||
bb93e3a5 | 1415 | static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg) |
1da177e4 | 1416 | { |
56b26add AV |
1417 | struct block_device *bdev = I_BDEV(file->f_mapping->host); |
1418 | fmode_t mode = file->f_mode; | |
fd4ce1ac CH |
1419 | |
1420 | /* | |
1421 | * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have | |
1422 | * to updated it before every ioctl. | |
1423 | */ | |
56b26add | 1424 | if (file->f_flags & O_NDELAY) |
fd4ce1ac CH |
1425 | mode |= FMODE_NDELAY; |
1426 | else | |
1427 | mode &= ~FMODE_NDELAY; | |
1428 | ||
56b26add | 1429 | return blkdev_ioctl(bdev, mode, cmd, arg); |
1da177e4 LT |
1430 | } |
1431 | ||
eef99380 CH |
1432 | /* |
1433 | * Write data to the block device. Only intended for the block device itself | |
1434 | * and the raw driver which basically is a fake block device. | |
1435 | * | |
1436 | * Does not take i_mutex for the write and thus is not for general purpose | |
1437 | * use. | |
1438 | */ | |
1439 | ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, | |
1440 | unsigned long nr_segs, loff_t pos) | |
1441 | { | |
1442 | struct file *file = iocb->ki_filp; | |
1443 | ssize_t ret; | |
1444 | ||
1445 | BUG_ON(iocb->ki_pos != pos); | |
1446 | ||
1447 | ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos); | |
1448 | if (ret > 0 || ret == -EIOCBQUEUED) { | |
1449 | ssize_t err; | |
1450 | ||
1451 | err = generic_write_sync(file, pos, ret); | |
1452 | if (err < 0 && ret > 0) | |
1453 | ret = err; | |
1454 | } | |
1455 | return ret; | |
1456 | } | |
1457 | EXPORT_SYMBOL_GPL(blkdev_aio_write); | |
1458 | ||
87d8fe1e TT |
1459 | /* |
1460 | * Try to release a page associated with block device when the system | |
1461 | * is under memory pressure. | |
1462 | */ | |
1463 | static int blkdev_releasepage(struct page *page, gfp_t wait) | |
1464 | { | |
1465 | struct super_block *super = BDEV_I(page->mapping->host)->bdev.bd_super; | |
1466 | ||
1467 | if (super && super->s_op->bdev_try_to_free_page) | |
1468 | return super->s_op->bdev_try_to_free_page(super, page, wait); | |
1469 | ||
1470 | return try_to_free_buffers(page); | |
1471 | } | |
1472 | ||
4c54ac62 | 1473 | static const struct address_space_operations def_blk_aops = { |
1da177e4 LT |
1474 | .readpage = blkdev_readpage, |
1475 | .writepage = blkdev_writepage, | |
1476 | .sync_page = block_sync_page, | |
6272b5a5 NP |
1477 | .write_begin = blkdev_write_begin, |
1478 | .write_end = blkdev_write_end, | |
1da177e4 | 1479 | .writepages = generic_writepages, |
87d8fe1e | 1480 | .releasepage = blkdev_releasepage, |
1da177e4 LT |
1481 | .direct_IO = blkdev_direct_IO, |
1482 | }; | |
1483 | ||
4b6f5d20 | 1484 | const struct file_operations def_blk_fops = { |
1da177e4 LT |
1485 | .open = blkdev_open, |
1486 | .release = blkdev_close, | |
1487 | .llseek = block_llseek, | |
543ade1f BP |
1488 | .read = do_sync_read, |
1489 | .write = do_sync_write, | |
1da177e4 | 1490 | .aio_read = generic_file_aio_read, |
eef99380 | 1491 | .aio_write = blkdev_aio_write, |
1da177e4 | 1492 | .mmap = generic_file_mmap, |
b1dd3b28 | 1493 | .fsync = blkdev_fsync, |
bb93e3a5 | 1494 | .unlocked_ioctl = block_ioctl, |
1da177e4 LT |
1495 | #ifdef CONFIG_COMPAT |
1496 | .compat_ioctl = compat_blkdev_ioctl, | |
1497 | #endif | |
7f9c51f0 JA |
1498 | .splice_read = generic_file_splice_read, |
1499 | .splice_write = generic_file_splice_write, | |
1da177e4 LT |
1500 | }; |
1501 | ||
1502 | int ioctl_by_bdev(struct block_device *bdev, unsigned cmd, unsigned long arg) | |
1503 | { | |
1504 | int res; | |
1505 | mm_segment_t old_fs = get_fs(); | |
1506 | set_fs(KERNEL_DS); | |
56b26add | 1507 | res = blkdev_ioctl(bdev, 0, cmd, arg); |
1da177e4 LT |
1508 | set_fs(old_fs); |
1509 | return res; | |
1510 | } | |
1511 | ||
1512 | EXPORT_SYMBOL(ioctl_by_bdev); | |
1513 | ||
1514 | /** | |
1515 | * lookup_bdev - lookup a struct block_device by name | |
94e2959e | 1516 | * @pathname: special file representing the block device |
1da177e4 | 1517 | * |
57d1b536 | 1518 | * Get a reference to the blockdevice at @pathname in the current |
1da177e4 LT |
1519 | * namespace if possible and return it. Return ERR_PTR(error) |
1520 | * otherwise. | |
1521 | */ | |
421748ec | 1522 | struct block_device *lookup_bdev(const char *pathname) |
1da177e4 LT |
1523 | { |
1524 | struct block_device *bdev; | |
1525 | struct inode *inode; | |
421748ec | 1526 | struct path path; |
1da177e4 LT |
1527 | int error; |
1528 | ||
421748ec | 1529 | if (!pathname || !*pathname) |
1da177e4 LT |
1530 | return ERR_PTR(-EINVAL); |
1531 | ||
421748ec | 1532 | error = kern_path(pathname, LOOKUP_FOLLOW, &path); |
1da177e4 LT |
1533 | if (error) |
1534 | return ERR_PTR(error); | |
1535 | ||
421748ec | 1536 | inode = path.dentry->d_inode; |
1da177e4 LT |
1537 | error = -ENOTBLK; |
1538 | if (!S_ISBLK(inode->i_mode)) | |
1539 | goto fail; | |
1540 | error = -EACCES; | |
421748ec | 1541 | if (path.mnt->mnt_flags & MNT_NODEV) |
1da177e4 LT |
1542 | goto fail; |
1543 | error = -ENOMEM; | |
1544 | bdev = bd_acquire(inode); | |
1545 | if (!bdev) | |
1546 | goto fail; | |
1547 | out: | |
421748ec | 1548 | path_put(&path); |
1da177e4 LT |
1549 | return bdev; |
1550 | fail: | |
1551 | bdev = ERR_PTR(error); | |
1552 | goto out; | |
1553 | } | |
d5686b44 | 1554 | EXPORT_SYMBOL(lookup_bdev); |
1da177e4 LT |
1555 | |
1556 | /** | |
30c40d2c | 1557 | * open_bdev_exclusive - open a block device by name and set it up for use |
1da177e4 LT |
1558 | * |
1559 | * @path: special file representing the block device | |
30c40d2c | 1560 | * @mode: FMODE_... combination to pass be used |
1da177e4 LT |
1561 | * @holder: owner for exclusion |
1562 | * | |
1563 | * Open the blockdevice described by the special file at @path, claim it | |
1564 | * for the @holder. | |
1565 | */ | |
30c40d2c | 1566 | struct block_device *open_bdev_exclusive(const char *path, fmode_t mode, void *holder) |
1da177e4 LT |
1567 | { |
1568 | struct block_device *bdev; | |
1da177e4 LT |
1569 | int error = 0; |
1570 | ||
1571 | bdev = lookup_bdev(path); | |
1572 | if (IS_ERR(bdev)) | |
1573 | return bdev; | |
1574 | ||
572c4892 | 1575 | error = blkdev_get(bdev, mode); |
1da177e4 LT |
1576 | if (error) |
1577 | return ERR_PTR(error); | |
1578 | error = -EACCES; | |
30c40d2c | 1579 | if ((mode & FMODE_WRITE) && bdev_read_only(bdev)) |
1da177e4 LT |
1580 | goto blkdev_put; |
1581 | error = bd_claim(bdev, holder); | |
1582 | if (error) | |
1583 | goto blkdev_put; | |
1584 | ||
1585 | return bdev; | |
1586 | ||
1587 | blkdev_put: | |
9a1c3542 | 1588 | blkdev_put(bdev, mode); |
1da177e4 LT |
1589 | return ERR_PTR(error); |
1590 | } | |
1591 | ||
30c40d2c | 1592 | EXPORT_SYMBOL(open_bdev_exclusive); |
1da177e4 LT |
1593 | |
1594 | /** | |
30c40d2c | 1595 | * close_bdev_exclusive - close a blockdevice opened by open_bdev_exclusive() |
1da177e4 LT |
1596 | * |
1597 | * @bdev: blockdevice to close | |
30c40d2c | 1598 | * @mode: mode, must match that used to open. |
1da177e4 | 1599 | * |
30c40d2c | 1600 | * This is the counterpart to open_bdev_exclusive(). |
1da177e4 | 1601 | */ |
30c40d2c | 1602 | void close_bdev_exclusive(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
1603 | { |
1604 | bd_release(bdev); | |
30c40d2c | 1605 | blkdev_put(bdev, mode); |
1da177e4 LT |
1606 | } |
1607 | ||
30c40d2c | 1608 | EXPORT_SYMBOL(close_bdev_exclusive); |
b71e8a4c DH |
1609 | |
1610 | int __invalidate_device(struct block_device *bdev) | |
1611 | { | |
1612 | struct super_block *sb = get_super(bdev); | |
1613 | int res = 0; | |
1614 | ||
1615 | if (sb) { | |
1616 | /* | |
1617 | * no need to lock the super, get_super holds the | |
1618 | * read mutex so the filesystem cannot go away | |
1619 | * under us (->put_super runs with the write lock | |
1620 | * hold). | |
1621 | */ | |
1622 | shrink_dcache_sb(sb); | |
1623 | res = invalidate_inodes(sb); | |
1624 | drop_super(sb); | |
1625 | } | |
f98393a6 | 1626 | invalidate_bdev(bdev); |
b71e8a4c DH |
1627 | return res; |
1628 | } | |
1629 | EXPORT_SYMBOL(__invalidate_device); |