[PATCH 00/13] client side user xattr (RFC8276) support

Frank van der Linden
2020-03-11T19:56:29Z

This patchset implements the client side for NFS user extended attributes,
as defined in RFC8726.

This was originally posted as an RFC in:

https://patchwork.kernel.org/cover/11143565/

Patch 1 is shared with the server side patch, posted
separately.

Most comments in there still apply, except that:

1. Client side caching is now included in this patch set.
2. As per the discussion, user extended attributes are enabled if
the client and server support them (e.g. they support 4.2 and
advertise the user extended attribute FATTR). There are no longer
options to switch them off on either the client or the server.
3. The code is no longer conditioned on a config option.
4. The number of patches has been reduced somewhat by merging
smaller, related ones.

The client side caching is implemented through a per-inode hash table,
which is allocated on demand. See fs/nfs/nfs42xattr.c for details.

This has been tested as follows:

* Linux client and server:
* Test all corner cases (XATTR_SIZE_*)
* Test all failure cases (no xattr, setxattr with different or
invalid flags, etc).
* Verify the content of xattrs across several operations.
* Use KASAN and KMEMLEAK for a longer mix of testruns to verify
that there were no leaks (after unmounting the filesystem).
* Stress tested caching, trying to run the client out of memory.

* Tested against the FreeBSD-current implementation as well, which works
(after I fixed 2 bugs in that implementation, which I'm sending out to
them too).

* Not tested: RDMA (I couldn't get a setup going).

Frank van der Linden (13):
nfs,nfsd: NFSv4.2 extended attribute protocol definitions
nfs: add client side only definitions for user xattrs
NFSv4.2: query the server for extended attribute support
NFSv4.2: define limits and sizes for user xattr handling
NFSv4.2: add client side XDR handling for extended attributes
nfs: define nfs_access_get_cached function
NFSv4.2: query the extended attribute access bits
nfs: modify update_changeattr to deal with regular files
nfs: define and use the NFS_INO_INVALID_XATTR flag
nfs: make the buf_to_pages_noslab function available to the nfs code
NFSv4.2: add the extended attribute proc functions.
NFSv4.2: hook in the user extended attribute handlers
NFSv4.2: add client side xattr caching.

fs/nfs/Makefile | 1 +
fs/nfs/client.c | 19 +-
fs/nfs/dir.c | 24 +-
fs/nfs/inode.c | 16 +-
fs/nfs/internal.h | 28 ++
fs/nfs/nfs42.h | 24 +
fs/nfs/nfs42proc.c | 248 ++++++++++
fs/nfs/nfs42xattr.c | 1083 +++++++++++++++++++++++++++++++++++++++++++
fs/nfs/nfs42xdr.c | 442 ++++++++++++++++++
fs/nfs/nfs4_fs.h | 5 +
fs/nfs/nfs4client.c | 31 ++
fs/nfs/nfs4proc.c | 248 ++++++++--
fs/nfs/nfs4super.c | 10 +
fs/nfs/nfs4xdr.c | 29 ++
fs/nfs/nfstrace.h | 3 +-
include/linux/nfs4.h | 25 +
include/linux/nfs_fs.h | 12 +
include/linux/nfs_fs_sb.h | 6 +
include/linux/nfs_xdr.h | 60 ++-
include/uapi/linux/nfs4.h | 3 +
include/uapi/linux/nfs_fs.h | 1 +
21 files changed, 2276 insertions(+), 42 deletions(-)
create mode 100644 fs/nfs/nfs42xattr.c

--
2.16.6