diff options
| author | Jan Kara <jack@suse.cz> | 2010-05-13 21:58:50 +0400 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2010-05-21 21:30:45 +0400 |
| commit | bc8e5f07392f05c47c8bdeff4f7098db440d065c (patch) | |
| tree | 5ab56dabd75912267764849a594ec2f271fd4352 /include | |
| parent | 12755627bdcddcdb30a1bfb9a09395a52b1d6838 (diff) | |
| download | linux-bc8e5f07392f05c47c8bdeff4f7098db440d065c.tar.xz | |
quota: Refactor dquot_transfer code so that OCFS2 can pass in its references
Currently, __dquot_transfer() acquires its own references of dquot structures
that will be put into inode. But for OCFS2, this creates a lock inversion
between dq_lock (waited on in dqget) and transaction start (started in
ocfs2_setattr). Currently, deadlock is impossible because dq_lock is acquired
only during dquot_acquire and dquot_release and we already hold a reference to
dquot structures in ocfs2_setattr so neither of these functions can be called
while we call dquot_transfer. But this is rather subtle and it is hard to teach
lockdep about it. So provide __dquot_transfer function that can be passed dquot
references directly. OCFS2 can then pass acquired dquot references directly to
__dquot_transfer with proper locking.
Signed-off-by: Jan Kara <jack@suse.cz>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/quotaops.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h index 8a7818764a67..370abb1e99cb 100644 --- a/include/linux/quotaops.h +++ b/include/linux/quotaops.h @@ -76,6 +76,7 @@ int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct fs_disk_quota *di); +int __dquot_transfer(struct inode *inode, struct dquot **transfer_to); int dquot_transfer(struct inode *inode, struct iattr *iattr); int vfs_dq_quota_on_remount(struct super_block *sb); |