Allow clients to request getting a delegation xor an open stateid if a delegation isn't available. This allows the client to avoid sending a final CLOSE for the (useless) open stateid, when it is granted a delegation. This is done by moving the increment of the open stateid and unlocking of the st_mutex until after we acquire a delegation. If we get a delegation, we zero out the op_stateid field and set the NO_OPEN_STATEID flag. If the open stateid was brand new, then unhash it too in this case since it won't be needed. If we can't get a delegation or the new flag wasn't requested, then just increment and copy the open stateid as usual. Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> --- fs/nfsd/nfs4state.c | 28 ++++++++++++++++++++++++---- fs/nfsd/nfs4xdr.c | 5 +++-- include/uapi/linux/nfs4.h | 7 +++++-- 3 files changed, 32 insertions(+), 8 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 9fe67c412f9b..b544320246bf 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -6029,6 +6029,17 @@ static void nfsd4_deleg_xgrade_none_ext(struct nfsd4_open *open, */ } +/* Are we only returning a delegation stateid? */ +static bool open_xor_delegation(struct nfsd4_open *open) +{ + if (!(open->op_deleg_want & OPEN4_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION)) + return false; + if (open->op_delegate_type != NFS4_OPEN_DELEGATE_READ && + open->op_delegate_type != NFS4_OPEN_DELEGATE_WRITE) + return false; + return true; +} + /** * nfsd4_process_open2 - finish open processing * @rqstp: the RPC transaction being executed @@ -6051,6 +6062,7 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf struct nfs4_delegation *dp = NULL; __be32 status; bool new_stp = false; + bool deleg_only = false; /* * Lookup file; if found, lookup stateid and check open request, @@ -6105,9 +6117,6 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf open->op_odstate = NULL; } - nfs4_inc_and_copy_stateid(&open->op_stateid, &stp->st_stid); - mutex_unlock(&stp->st_mutex); - if (nfsd4_has_session(&resp->cstate)) { if (open->op_deleg_want & NFS4_SHARE_WANT_NO_DELEG) { open->op_delegate_type = NFS4_OPEN_DELEGATE_NONE_EXT; @@ -6121,7 +6130,18 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf * OPEN succeeds even if we fail. */ nfs4_open_delegation(open, stp, &resp->cstate.current_fh); + deleg_only = open_xor_delegation(open); nodeleg: + if (deleg_only) { + memcpy(&open->op_stateid, &zero_stateid, sizeof(open->op_stateid)); + open->op_rflags |= OPEN4_RESULT_NO_OPEN_STATEID; + if (new_stp) + release_open_stateid(stp); + } else { + nfs4_inc_and_copy_stateid(&open->op_stateid, &stp->st_stid); + } + mutex_unlock(&stp->st_mutex); + status = nfs_ok; trace_nfsd_open(&stp->st_stid.sc_stateid); out: @@ -6137,7 +6157,7 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf /* * To finish the open response, we just need to set the rflags. */ - open->op_rflags = NFS4_OPEN_RESULT_LOCKTYPE_POSIX; + open->op_rflags |= NFS4_OPEN_RESULT_LOCKTYPE_POSIX; if (nfsd4_has_session(&resp->cstate)) open->op_rflags |= NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK; else if (!(open->op_openowner->oo_flags & NFS4_OO_CONFIRMED)) diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 1c8219ea8af7..8266f910d847 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -1066,7 +1066,7 @@ static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *sh return nfs_ok; if (!argp->minorversion) return nfserr_bad_xdr; - switch (w & NFS4_SHARE_WANT_MASK) { + switch (w & NFS4_SHARE_WANT_TYPE_MASK) { case NFS4_SHARE_WANT_NO_PREFERENCE: case NFS4_SHARE_WANT_READ_DELEG: case NFS4_SHARE_WANT_WRITE_DELEG: @@ -3410,7 +3410,8 @@ static __be32 nfsd4_encode_fattr4_xattr_support(struct xdr_stream *xdr, #define NFSD_OA_SHARE_ACCESS_WANT (BIT(OPEN_ARGS_SHARE_ACCESS_WANT_ANY_DELEG) | \ BIT(OPEN_ARGS_SHARE_ACCESS_WANT_NO_DELEG) | \ - BIT(OPEN_ARGS_SHARE_ACCESS_WANT_CANCEL)) + BIT(OPEN_ARGS_SHARE_ACCESS_WANT_CANCEL) | \ + BIT(OPEN_ARGS_SHARE_ACCESS_WANT_OPEN_XOR_DELEGATION)) #define NFSD_OA_OPEN_CLAIM (BIT(OPEN_ARGS_OPEN_CLAIM_NULL) | \ BIT(OPEN_ARGS_OPEN_CLAIM_PREVIOUS) | \ diff --git a/include/uapi/linux/nfs4.h b/include/uapi/linux/nfs4.h index caf4db2fcbb9..4273e0249fcb 100644 --- a/include/uapi/linux/nfs4.h +++ b/include/uapi/linux/nfs4.h @@ -58,7 +58,7 @@ #define NFS4_SHARE_DENY_BOTH 0x0003 /* nfs41 */ -#define NFS4_SHARE_WANT_MASK 0xFF00 +#define NFS4_SHARE_WANT_TYPE_MASK 0xFF00 #define NFS4_SHARE_WANT_NO_PREFERENCE 0x0000 #define NFS4_SHARE_WANT_READ_DELEG 0x0100 #define NFS4_SHARE_WANT_WRITE_DELEG 0x0200 @@ -66,13 +66,16 @@ #define NFS4_SHARE_WANT_NO_DELEG 0x0400 #define NFS4_SHARE_WANT_CANCEL 0x0500 -#define NFS4_SHARE_WHEN_MASK 0xF0000 +#define NFS4_SHARE_WHEN_MASK 0xF0000 #define NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL 0x10000 #define NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED 0x20000 +#define NFS4_SHARE_WANT_MOD_MASK 0xF00000 #define NFS4_SHARE_WANT_DELEG_TIMESTAMPS 0x100000 #define NFS4_SHARE_WANT_OPEN_XOR_DELEGATION 0x200000 +#define NFS4_SHARE_WANT_MASK (NFS4_SHARE_WANT_TYPE_MASK | NFS4_SHARE_WANT_MOD_MASK) + #define NFS4_CDFC4_FORE 0x1 #define NFS4_CDFC4_BACK 0x2 #define NFS4_CDFC4_BOTH 0x3 -- 2.46.0