may be needed. We can validate cached dentries in two ways. A per-dentry lease may be issued by the MDS, or a per-directory cap may be issued that acts as a lease on the entire directory. In the latter case, a 'gen' value is used to determine which dentries belong to the currently leased directory contents. We normally prepopulate the dcache and icache with readdir results. This makes subsequent lookups and getattrs avoid any server interaction. It also lets us satisfy readdir operation by peeking at the dcache IFF we hold the per-directory cap/lease, previously performed a readdir, and haven't dropped any of the resulting dentries. Signed-off-by: Sage Weil ±WôF”"x