reiserfs: locking, release lock around quota operations
Previous commits released the write lock across quota operations but
missed several places. In particular, the free operations can also
call into the file system code and take the write lock, causing
deadlocks.
This patch introduces some more helpers and uses them for quota call
sites. Without this patch applied, reiserfs + quotas runs into deadlocks
under anything more than trivial load.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index 4a3a57c..ad62bdb 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -57,8 +57,11 @@
/* Do quota update inside a transaction for journaled quotas. We must do that
* after delete_object so that quota updates go into the same transaction as
* stat data deletion */
- if (!err)
+ if (!err) {
+ int depth = reiserfs_write_unlock_nested(inode->i_sb);
dquot_free_inode(inode);
+ reiserfs_write_lock_nested(inode->i_sb, depth);
+ }
if (journal_end(&th, inode->i_sb, jbegin_count))
goto out;
@@ -1768,7 +1771,7 @@
struct inode *inode,
struct reiserfs_security_handle *security)
{
- struct super_block *sb;
+ struct super_block *sb = dir->i_sb;
struct reiserfs_iget_args args;
INITIALIZE_PATH(path_to_key);
struct cpu_key key;
@@ -1780,9 +1783,9 @@
BUG_ON(!th->t_trans_id);
- reiserfs_write_unlock(inode->i_sb);
+ depth = reiserfs_write_unlock_nested(sb);
err = dquot_alloc_inode(inode);
- reiserfs_write_lock(inode->i_sb);
+ reiserfs_write_lock_nested(sb, depth);
if (err)
goto out_end_trans;
if (!dir->i_nlink) {
@@ -1790,8 +1793,6 @@
goto out_bad_inode;
}
- sb = dir->i_sb;
-
/* item head of new item */
ih.ih_key.k_dir_id = reiserfs_choose_packing(dir);
ih.ih_key.k_objectid = cpu_to_le32(reiserfs_get_unused_objectid(th));
@@ -1983,14 +1984,16 @@
INODE_PKEY(inode)->k_objectid = 0;
/* Quota change must be inside a transaction for journaling */
+ depth = reiserfs_write_unlock_nested(inode->i_sb);
dquot_free_inode(inode);
+ reiserfs_write_lock_nested(inode->i_sb, depth);
out_end_trans:
journal_end(th, th->t_super, th->t_blocks_allocated);
- reiserfs_write_unlock(inode->i_sb);
/* Drop can be outside and it needs more credits so it's better to have it outside */
+ depth = reiserfs_write_unlock_nested(inode->i_sb);
dquot_drop(inode);
- reiserfs_write_lock(inode->i_sb);
+ reiserfs_write_lock_nested(inode->i_sb, depth);
inode->i_flags |= S_NOQUOTA;
make_bad_inode(inode);