tree 0065bcc05b19a99d8785ce523f992a48fe573e79
parent 79835a710d6ff811659c8de46f89c7577c3b8cc6
author J. Bruce Fields <bfields@redhat.com> 1316617093 -0400
committer root <root@serles.lst.de> 1319806740 +0200

leases: fix write-open/read-lease race

In setlease, we use i_writecount to decide whether we can give out a
read lease.

In open, we break leases before incrementing i_writecount.

There is therefore a window between the break lease and the i_writecount
increment when setlease could add a new read lease.

This would leave us with a simultaneous write open and read lease, which
shouldn't happen.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>