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>
This commit is contained in:
Jeff Layton 2014-08-12 08:03:49 -04:00
parent 566709bd62
commit b84d49f944

View File

@ -1022,18 +1022,21 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
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;
}
}