tree eb4f9a0418e1190958603360cf9bcea0cbb67727
parent 63ab46abc70b01cb0711301f5ddb08c1c0bb9b1c
author Chuck Lever <cel@netapp.com> 1142880272 -0500
committer Trond Myklebust <Trond.Myklebust@netapp.com> 1142880272 -0500

NFS: make direct write path generate write requests concurrently

Duplicate infrastructure from direct read path that will allow write
path to generate multiple write requests concurrently.  This will
enable us to add support for aio in this path.

Temporarily we will lose the ability to do UNSTABLE writes followed by
a COMMIT in the direct write path.  However, all applications I am
aware of that use NFS O_DIRECT currently write in relatively small
chunks, so this should not be inconvenient in any way.

Test plan:
Millions of fsx-odirect ops. OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>