[RFC PATCH 0/3] Initial NFS client support for RWF_DONTCACHE

[trondmy@kernel.org]

From: Trond Myklebust <trond.myklebust@hammerspace.com>

The following patch set attempts to add support for the RWF_DONTCACHE
flag in preadv2() and pwritev2() on NFS filesystems.

The main issue is allowing support on 2 stage writes (i.e. unstable
WRITE followed by a COMMIT) since those don't follow the current
assumption that the 'dropbehind' flag can be fulfilled as soon as the
writeback lock is dropped.

Trond Myklebust (3):
  filemap: Add a helper for filesystems implementing dropbehind
  filemap: Mark folios as dropbehind in generic_perform_write()
  NFS: Enable the RWF_DONTCACHE flag for the NFS client

 fs/nfs/file.c            |  2 ++
 fs/nfs/nfs4file.c        |  2 ++
 fs/nfs/write.c           | 12 +++++++++++-
 include/linux/nfs_page.h |  1 +
 include/linux/pagemap.h  |  1 +
 mm/filemap.c             | 21 +++++++++++++++++++++
 6 files changed, 38 insertions(+), 1 deletion(-)

-- 
2.49.0