1d3dd1d56c
This patch grants write delegations for OPEN with NFS4_SHARE_ACCESS_WRITE if there is no conflict with other OPENs. Write delegation conflicts with another OPEN, REMOVE, RENAME and SETATTR are handled the same as read delegation using notify_change, try_break_deleg. The NFSv4.0 protocol does not enable a server to determine that a conflicting GETATTR originated from the client holding the delegation versus coming from some other client. With NFSv4.1 and later, the SEQUENCE operation that begins each COMPOUND contains a client ID, so delegation recall can be safely squelched in this case. With NFSv4.0, however, the server must recall or send a CB_GETATTR (per RFC 7530 Section 16.7.5) even when the GETATTR originates from the client holding that delegation. An NFSv4.0 client can trigger a pathological situation if it always sends a DELEGRETURN preceded by a conflicting GETATTR in the same COMPOUND. COMPOUND execution will always stop at the GETATTR and the DELEGRETURN will never get executed. The server eventually revokes the delegation, which can result in loss of open or lock state. Tracepoint added to track whether read or write delegation is granted. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> |
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.. | ||
acl.h | ||
auth.c | ||
auth.h | ||
blocklayout.c | ||
blocklayoutxdr.c | ||
blocklayoutxdr.h | ||
cache.h | ||
current_stateid.h | ||
export.c | ||
export.h | ||
filecache.c | ||
filecache.h | ||
flexfilelayout.c | ||
flexfilelayoutxdr.c | ||
flexfilelayoutxdr.h | ||
idmap.h | ||
Kconfig | ||
lockd.c | ||
Makefile | ||
netns.h | ||
nfs2acl.c | ||
nfs3acl.c | ||
nfs3proc.c | ||
nfs3xdr.c | ||
nfs4acl.c | ||
nfs4callback.c | ||
nfs4idmap.c | ||
nfs4layouts.c | ||
nfs4proc.c | ||
nfs4recover.c | ||
nfs4state.c | ||
nfs4xdr.c | ||
nfscache.c | ||
nfsctl.c | ||
nfsd.h | ||
nfsfh.c | ||
nfsfh.h | ||
nfsproc.c | ||
nfssvc.c | ||
nfsxdr.c | ||
pnfs.h | ||
state.h | ||
stats.c | ||
stats.h | ||
trace.c | ||
trace.h | ||
vfs.c | ||
vfs.h | ||
xdr3.h | ||
xdr4.h | ||
xdr4cb.h | ||
xdr.h |