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| author | Mikulas Patocka <mpatocka@redhat.com> | 2009-06-22 13:12:14 +0400 |
|---|---|---|
| committer | Alasdair G Kergon <agk@redhat.com> | 2009-06-22 13:12:14 +0400 |
| commit | 5657e8fa45cf230df278040c420fb80e06309d8f (patch) | |
| tree | 7817e1bd6c9b721be85fe54a1aec6ef971d7d96b | |
| parent | 8cbeb67ad50f7d68e5e83be2cb2284de8f9c03b5 (diff) | |
| download | linux-5657e8fa45cf230df278040c420fb80e06309d8f.tar.xz | |
dm: use i_size_read
Use i_size_read() instead of reading i_size.
If someone changes the size of the device simultaneously, i_size_read
is guaranteed to return a valid value (either the old one or the new one).
i_size can return some intermediate invalid value (on 32-bit computers
with 64-bit i_size, the reads to both halves of i_size can be interleaved
with updates to i_size, resulting in garbage being returned).
Cc: stable@kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
| -rw-r--r-- | drivers/md/dm-exception-store.h | 2 | ||||
| -rw-r--r-- | drivers/md/dm-log.c | 2 | ||||
| -rw-r--r-- | drivers/md/dm-table.c | 3 |
3 files changed, 4 insertions, 3 deletions
diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h index c92701dc5001..2442c8c07898 100644 --- a/drivers/md/dm-exception-store.h +++ b/drivers/md/dm-exception-store.h @@ -156,7 +156,7 @@ static inline void dm_consecutive_chunk_count_inc(struct dm_snap_exception *e) */ static inline sector_t get_dev_size(struct block_device *bdev) { - return bdev->bd_inode->i_size >> SECTOR_SHIFT; + return i_size_read(bdev->bd_inode) >> SECTOR_SHIFT; } static inline chunk_t sector_to_chunk(struct dm_exception_store *store, diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c index 6fa8ccf91c70..6352a9ad4446 100644 --- a/drivers/md/dm-log.c +++ b/drivers/md/dm-log.c @@ -416,7 +416,7 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti, bitset_size, ti->limits.logical_block_size); - if (buf_size > dev->bdev->bd_inode->i_size) { + if (buf_size > i_size_read(dev->bdev->bd_inode)) { DMWARN("log device %s too small: need %llu bytes", dev->name, (unsigned long long)buf_size); kfree(lc); diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index e9a73bb242b0..0e2210c0c168 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -388,7 +388,8 @@ static void close_dev(struct dm_dev_internal *d, struct mapped_device *md) static int check_device_area(struct dm_dev_internal *dd, sector_t start, sector_t len) { - sector_t dev_size = dd->dm_dev.bdev->bd_inode->i_size >> SECTOR_SHIFT; + sector_t dev_size = i_size_read(dd->dm_dev.bdev->bd_inode) >> + SECTOR_SHIFT; if (!dev_size) return 1; |