From 07e8dcbda71ef87e9cbdc42b5bb16a44c1ab839b Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sun, 28 Aug 2016 10:28:25 -0400 Subject: [PATCH] NFSv4.1: Defer bumping the slot sequence number until we free the slot For operations like OPEN or LAYOUTGET, which return recallable state (i.e. delegations and layouts) we want to enable the mechanism for resolving recall races in RFC5661 Section 2.10.6.3. To do so, we will want to defer bumping the slot's sequence number until we have finished processing the RPC results. Signed-off-by: Trond Myklebust --- fs/nfs/nfs4proc.c | 9 +++++++-- fs/nfs/nfs4session.h | 3 ++- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 0cc0c31..de4a89d 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -666,6 +666,11 @@ static void nfs41_sequence_free_slot(struct nfs4_sequence_res *res) tbl = slot->table; session = tbl->session; + /* Bump the slot sequence number */ + if (slot->seq_done) + slot->seq_nr++; + slot->seq_done = 0; + spin_lock(&tbl->slot_tbl_lock); /* Be nice to the server: try to ensure that the last transmitted * value for highest_user_slotid <= target_highest_slotid @@ -716,7 +721,7 @@ int nfs41_sequence_done(struct rpc_task *task, struct nfs4_sequence_res *res) switch (res->sr_status) { case 0: /* Update the slot's sequence and clientid lease timer */ - ++slot->seq_nr; + slot->seq_done = 1; clp = session->clp; do_renew_lease(clp, res->sr_timestamp); /* Check sequence flags */ @@ -771,7 +776,7 @@ int nfs41_sequence_done(struct rpc_task *task, struct nfs4_sequence_res *res) goto retry_nowait; default: /* Just update the slot sequence no. */ - ++slot->seq_nr; + slot->seq_done = 1; } out: /* The session may be reset by one of the error handlers. */ diff --git a/fs/nfs/nfs4session.h b/fs/nfs/nfs4session.h index fa75d7d..f703b75 100644 --- a/fs/nfs/nfs4session.h +++ b/fs/nfs/nfs4session.h @@ -21,7 +21,8 @@ struct nfs4_slot { unsigned long generation; u32 slot_nr; u32 seq_nr; - unsigned int interrupted : 1; + unsigned int interrupted : 1, + seq_done : 1; }; /* Sessions */ -- 2.7.4