[PATCH 00/14] server side user xattr support (RFC 8276)

Frank van der Linden
2020-03-11T20:00:03Z

This patchset implements the server 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 client side patch, posted
separately.

Most comments in there still apply, except that:

1. 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.
2. The code is no longer conditioned on a config option.
3. The number of patches has been reduced somewhat by merging
smaller, related ones.

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).

* 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 (14):
nfs,nfsd: NFSv4.2 extended attribute protocol definitions
xattr: modify vfs_{set,remove}xattr for NFS server use
nfsd: split off the write decode code in to a separate function
nfsd: make sure the nfsd4_ops array has the right size
nfsd: add defines for NFSv4.2 extended attribute support
nfsd: define xattr functions to call in to their vfs counterparts
nfsd: take xattr bits in to account for permission checks
nfsd: add structure definitions for xattr requests / responses
nfsd: use kvmalloc in svcxdr_tmpalloc
nfsd: implement the xattr procedure functions.
nfsd: add user xattr RPC XDR encoding/decoding logic
nfsd: add xattr operations to ops array
xattr: add a function to check if a namespace is supported
nfsd: add fattr support for user extended attributes

fs/nfsd/nfs4proc.c | 141 +++++++++++-
fs/nfsd/nfs4xdr.c | 535 +++++++++++++++++++++++++++++++++++++++++++---
fs/nfsd/nfsd.h | 5 +-
fs/nfsd/vfs.c | 142 ++++++++++++
fs/nfsd/vfs.h | 10 +
fs/nfsd/xdr4.h | 31 +++
fs/xattr.c | 90 +++++++-
include/linux/nfs4.h | 22 +-
include/linux/xattr.h | 4 +
include/uapi/linux/nfs4.h | 3 +
10 files changed, 940 insertions(+), 43 deletions(-)

--
2.16.6