linux-stable/fs/nfsd
Jeff Layton daab110e47 nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operations
With NFSv3 nfsd will always attempt to send along WCC data to the
client. This generally involves saving off the in-core inode information
prior to doing the operation on the given filehandle, and then issuing a
vfs_getattr to it after the op.

Some filesystems (particularly clustered or networked ones) have an
expensive ->getattr inode operation. Atomicity is also often difficult
or impossible to guarantee on such filesystems. For those, we're best
off not trying to provide WCC information to the client at all, and to
simply allow it to poll for that information as needed with a GETATTR
RPC.

This patch adds a new flags field to struct export_operations, and
defines a new EXPORT_OP_NOWCC flag that filesystems can use to indicate
that nfsd should not attempt to provide WCC info in NFSv3 replies. It
also adds a blurb about the new flags field and flag to the exporting
documentation.

The server will also now skip collecting this information for NFSv2 as
well, since that info is never used there anyway.

Note that this patch does not add this flag to any filesystem
export_operations structures. This was originally developed to allow
reexporting nfs via nfsd.

Other filesystems may want to consider enabling this flag too. It's hard
to tell however which ones have export operations to enable export via
knfsd and which ones mostly rely on them for open-by-filehandle support,
so I'm leaving that up to the individual maintainers to decide. I am
cc'ing the relevant lists for those filesystems that I think may want to
consider adding this though.

Cc: HPDD-discuss@lists.01.org
Cc: ceph-devel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: fuse-devel@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-12-09 09:39:38 -05:00
..
acl.h nfsd: eliminate an unnecessary acl size limit 2019-08-28 21:13:45 -04:00
auth.c nfsd: auth: Fix gid sorting when rootsquash enabled 2018-01-22 20:13:07 -08:00
auth.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
blocklayout.c block: add a bdev_is_partition helper 2020-09-25 08:18:57 -06:00
blocklayoutxdr.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
blocklayoutxdr.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cache.h nfsd4: make drc_slab global, not per-net 2020-06-01 17:44:45 -04:00
current_stateid.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
export.c NFSD: Map nfserr_wrongsec outside of nfsd_dispatch 2020-10-02 09:37:42 -04:00
export.h knfsd: Allow lockless lookups of the exports 2018-10-29 16:58:04 -04:00
fault_inject.c nfsd: no need to check return value of debugfs_create functions 2019-07-03 16:57:17 +02:00
filecache.c nfsd: Fix error return code in nfsd_file_cache_init() 2020-11-30 14:45:56 -05:00
filecache.h nfsd: convert file cache to use over/underflow safe refcount 2020-02-06 11:22:55 -05:00
flexfilelayout.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
flexfilelayoutxdr.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
flexfilelayoutxdr.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
idmap.h
Kconfig NFSv4.2: Fix NFS4ERR_STALE error when doing inter server copy 2020-10-21 10:31:20 -04:00
lockd.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile nfsd: remove fault injection code 2020-09-25 18:01:26 -04:00
netns.h nfsd: netns.h: delete a duplicated word 2020-07-24 17:25:13 -04:00
nfs2acl.c NFSD: Add common helpers to decode void args and encode void results 2020-11-30 14:46:35 -05:00
nfs3acl.c NFSD: Add common helpers to decode void args and encode void results 2020-11-30 14:46:35 -05:00
nfs3proc.c NFSD: Add common helpers to decode void args and encode void results 2020-11-30 14:46:35 -05:00
nfs3xdr.c nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operations 2020-12-09 09:39:38 -05:00
nfs4acl.c nfsd: check permissions when setting ACLs 2016-06-24 12:11:52 -04:00
nfs4callback.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
nfs4idmap.c nfsd: Use seq_putc() in two functions 2020-07-13 17:28:46 -04:00
nfs4layouts.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
nfs4proc.c NFSD: Fix sparse warning in nfs4proc.c 2020-12-09 09:38:34 -05:00
nfs4recover.c nfsd: avoid a NULL dereference in __cld_pipe_upcall() 2020-07-13 17:28:46 -04:00
nfs4state.c NFSD: Fix 5 seconds delay when doing inter server copy 2020-12-09 09:38:34 -05:00
nfs4xdr.c Revert "nfsd4: support change_attr_type attribute" 2020-12-09 09:39:38 -05:00
nfscache.c silence nfscache allocation warnings with kvzalloc 2020-09-25 18:01:28 -04:00
nfsctl.c nfsd: remove fault injection code 2020-09-25 18:01:26 -04:00
nfsd.h Revert "nfsd4: support change_attr_type attribute" 2020-12-09 09:39:38 -05:00
nfsfh.c nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operations 2020-12-09 09:39:38 -05:00
nfsfh.h nfsd: add a new EXPORT_OP_NOWCC flag to struct export_operations 2020-12-09 09:39:38 -05:00
nfsproc.c NFSD: Add common helpers to decode void args and encode void results 2020-11-30 14:46:35 -05:00
nfssvc.c nfsd: Fix message level for normal termination 2020-12-09 09:38:33 -05:00
nfsxdr.c NFSD: Add common helpers to decode void args and encode void results 2020-11-30 14:46:35 -05:00
pnfs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
state.h nfsd: remove fault injection code 2020-09-25 18:01:26 -04:00
stats.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
stats.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace.c NFSD: Add SPDX header for fs/nfsd/trace.c 2020-11-30 13:00:24 -05:00
trace.h NFSD: Add tracepoints in nfsd4_decode/encode_compound() 2020-11-30 14:46:35 -05:00
vfs.c NFSD: Correct type annotations in user xattr helpers 2020-09-25 18:01:27 -04:00
vfs.h nfsd: define xattr functions to call into their vfs counterparts 2020-07-13 17:27:03 -04:00
xdr.h NFSD: Add common helpers to decode void args and encode void results 2020-11-30 14:46:35 -05:00
xdr3.h NFSD: Add common helpers to decode void args and encode void results 2020-11-30 14:46:35 -05:00
xdr4.h nfsd: simplify nfsd4_change_info 2020-12-09 09:39:37 -05:00
xdr4cb.h NFSD CB_OFFLOAD xdr 2018-09-25 20:34:54 -04:00