reiserfs: Move quota calls out of write lock

Calls into highlevel quota code cannot happen under the write lock. These
calls take dqio_mutex which ranks above write lock. So drop write lock
before calling back into quota code.

CC: stable@vger.kernel.org # >= 3.0
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/reiserfs/stree.c b/fs/reiserfs/stree.c
index f8afa4b..2f40a4c 100644
--- a/fs/reiserfs/stree.c
+++ b/fs/reiserfs/stree.c
@@ -1968,7 +1968,9 @@
 		       key2type(&(key->on_disk_key)));
 #endif
 
+	reiserfs_write_unlock(inode->i_sb);
 	retval = dquot_alloc_space_nodirty(inode, pasted_size);
+	reiserfs_write_lock(inode->i_sb);
 	if (retval) {
 		pathrelse(search_path);
 		return retval;
@@ -2061,9 +2063,11 @@
 			       "reiserquota insert_item(): allocating %u id=%u type=%c",
 			       quota_bytes, inode->i_uid, head2type(ih));
 #endif
+		reiserfs_write_unlock(inode->i_sb);
 		/* We can't dirty inode here. It would be immediately written but
 		 * appropriate stat item isn't inserted yet... */
 		retval = dquot_alloc_space_nodirty(inode, quota_bytes);
+		reiserfs_write_lock(inode->i_sb);
 		if (retval) {
 			pathrelse(path);
 			return retval;