locks: don't reuse file_lock in __posix_lock_file
Currently in the case where a new file lock completely replaces the old
one, we end up overwriting the existing lock with the new info. This
means that we have to call fl_release_private inside i_lock. Change the
code to instead copy the info to new_fl, insert that lock into the
correct spot and then delete the old lock. In a later patch, we'll defer
the freeing of the old lock until after the i_lock has been dropped.
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
diff --git a/fs/locks.c b/fs/locks.c
index 2c2d4f5..7dd4def 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1022,18 +1022,21 @@
locks_delete_lock(before);
continue;
}
- /* Replace the old lock with the new one.
- * Wake up anybody waiting for the old one,
- * as the change in lock type might satisfy
- * their needs.
+ /*
+ * Replace the old lock with new_fl, and
+ * remove the old one. It's safe to do the
+ * insert here since we know that we won't be
+ * using new_fl later, and that the lock is
+ * just replacing an existing lock.
*/
- locks_wake_up_blocks(fl);
- fl->fl_start = request->fl_start;
- fl->fl_end = request->fl_end;
- fl->fl_type = request->fl_type;
- locks_release_private(fl);
- locks_copy_private(fl, request);
- request = fl;
+ error = -ENOLCK;
+ if (!new_fl)
+ goto out;
+ locks_copy_lock(new_fl, request);
+ request = new_fl;
+ new_fl = NULL;
+ locks_delete_lock(before);
+ locks_insert_lock(before, request);
added = true;
}
}