This update further fine tunes the locking of snapshot vnodes in the ffs_copyonwrite routine to avoid a deadlock between the syncer daemon trying to sync out a snapshot vnode and the bufdaemon trying to write out a buffer containing the snapshot inode. With any luck this will be the last snapshot race condition.
This update further fine tunes the locking of snapshot vnodes in
the ffs_copyonwrite routine to avoid a deadlock between the syncer
daemon trying to sync out a snapshot vnode and the bufdaemon
trying to write out a buffer containing the snapshot inode.
With any luck this will be the last snapshot race condition.

Sponsored by:	DARPA & NAI Labs.

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