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| author | OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> | 2008-11-06 21:53:57 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-11-07 00:41:21 +0100 |
| commit | 2bdf67eb1631f30e2f3f5d49e4007c76e88877a8 (patch) | |
| tree | d3d337e52516b3b61cdf4508cf445ef8dcaae2ed /fs/fat/fat.h | |
| parent | fat: Add printf attribute to fat_fs_panic() (diff) | |
| download | linux-2bdf67eb1631f30e2f3f5d49e4007c76e88877a8.tar.xz linux-2bdf67eb1631f30e2f3f5d49e4007c76e88877a8.zip | |
fat: mmu_private race fix
mmu_private is 64bits value, hence it's not atomic to update.
So, the access rule for mmu_private is we must hold ->i_mutex. But,
fat_get_block() path doesn't follow the rule on non-allocation path.
This fixes by using i_size instead if non-allocation path.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/fat/fat.h')
| -rw-r--r-- | fs/fat/fat.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/fat/fat.h b/fs/fat/fat.h index a69f7f9757c0..4efc5038ed29 100644 --- a/fs/fat/fat.h +++ b/fs/fat/fat.h @@ -91,7 +91,9 @@ struct msdos_inode_info { /* for avoiding the race between fat_free() and fat_get_cluster() */ unsigned int cache_valid_id; - loff_t mmu_private; + /* NOTE: mmu_private is 64bits, so must hold ->i_mutex to access */ + loff_t mmu_private; /* physically allocated size */ + int i_start; /* first cluster or 0 */ int i_logstart; /* logical first cluster */ int i_attrs; /* unused attribute bits */ @@ -222,7 +224,7 @@ extern void fat_cache_inval_inode(struct inode *inode); extern int fat_get_cluster(struct inode *inode, int cluster, int *fclus, int *dclus); extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, - unsigned long *mapped_blocks); + unsigned long *mapped_blocks, int create); /* fat/dir.c */ extern const struct file_operations fat_dir_operations; |