diff options
| author | Hou Tao <houtao1@huawei.com> | 2022-12-16 05:23:53 +0100 |
|---|---|---|
| committer | Mike Snitzer <snitzer@kernel.org> | 2023-02-17 20:49:21 +0100 |
| commit | a2f998a78a425edde5a1a1973c1d4854fe9d019f (patch) | |
| tree | 291cf12c7f177e9c60fbc9a0772b69364f64cf80 /drivers/md | |
| parent | dm ioctl: assert _hash_lock is held in __hash_remove (diff) | |
| download | linux-a2f998a78a425edde5a1a1973c1d4854fe9d019f.tar.xz linux-a2f998a78a425edde5a1a1973c1d4854fe9d019f.zip | |
dm ioctl: remove unnecessary check when using dm_get_mdptr()
__hash_remove() removes hash_cell with _hash_lock locked, so acquiring
_hash_lock can guarantee no-NULL hc returned from dm_get_mdptr() must
have not been removed and hc->md must still be md.
__hash_remove() also acquires dm_hash_cells_mutex before setting mdptr
as NULL. So in dm_copy_name_and_uuid(), after acquiring
dm_hash_cells_mutex and ensuring returned hc is not NULL, the returned
hc must still be alive and hc->md must still be md.
Remove the unnecessary hc->md != md checks when using dm_get_mdptr()
with _hash_lock or dm_hash_cells_mutex acquired.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-ioctl.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 067dfc08d4c3..50a1259294d1 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -789,7 +789,7 @@ static struct dm_table *dm_get_inactive_table(struct mapped_device *md, int *src down_read(&_hash_lock); hc = dm_get_mdptr(md); - if (!hc || hc->md != md) { + if (!hc) { DMERR("device has been removed from the dev hash table."); goto out; } @@ -1500,7 +1500,7 @@ static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_si /* stage inactive table */ down_write(&_hash_lock); hc = dm_get_mdptr(md); - if (!hc || hc->md != md) { + if (!hc) { DMERR("device has been removed from the dev hash table."); up_write(&_hash_lock); r = -ENXIO; @@ -2152,7 +2152,7 @@ int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid) mutex_lock(&dm_hash_cells_mutex); hc = dm_get_mdptr(md); - if (!hc || hc->md != md) { + if (!hc) { r = -ENXIO; goto out; } |