From b0ef9647a0cd6cfd63fed48fbbe6005e4ba92571 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 11 Dec 2012 12:10:14 -0500 Subject: [PATCH] NFSv4.1: Be conservative about the client highest slotid If the server sends us a target that looks like an outlier, but is lower than the existing target, then respect it anyway. However defer actually updating the generation counter until we get a target that doesn't look like an outlier. Signed-off-by: Trond Myklebust --- fs/nfs/nfs4session.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/fs/nfs/nfs4session.c b/fs/nfs/nfs4session.c index ed5aa9fa9c7b..1e6c87c443a7 100644 --- a/fs/nfs/nfs4session.c +++ b/fs/nfs/nfs4session.c @@ -273,20 +273,28 @@ void nfs41_wake_slot_table(struct nfs4_slot_table *tbl) } } +static void nfs41_set_max_slotid_locked(struct nfs4_slot_table *tbl, + u32 target_highest_slotid) +{ + u32 max_slotid; + + max_slotid = min(NFS4_MAX_SLOT_TABLE - 1, target_highest_slotid); + if (max_slotid > tbl->server_highest_slotid) + max_slotid = tbl->server_highest_slotid; + if (max_slotid > tbl->target_highest_slotid) + max_slotid = tbl->target_highest_slotid; + tbl->max_slotid = max_slotid; + nfs41_wake_slot_table(tbl); +} + /* Update the client's idea of target_highest_slotid */ static void nfs41_set_target_slotid_locked(struct nfs4_slot_table *tbl, u32 target_highest_slotid) { - unsigned int max_slotid; - if (tbl->target_highest_slotid == target_highest_slotid) return; tbl->target_highest_slotid = target_highest_slotid; tbl->generation++; - - max_slotid = min(NFS4_MAX_SLOT_TABLE - 1, tbl->target_highest_slotid); - tbl->max_slotid = max_slotid; - nfs41_wake_slot_table(tbl); } void nfs41_set_target_slotid(struct nfs4_slot_table *tbl, @@ -296,6 +304,7 @@ void nfs41_set_target_slotid(struct nfs4_slot_table *tbl, nfs41_set_target_slotid_locked(tbl, target_highest_slotid); tbl->d_target_highest_slotid = 0; tbl->d2_target_highest_slotid = 0; + nfs41_set_max_slotid_locked(tbl, target_highest_slotid); spin_unlock(&tbl->slot_tbl_lock); } @@ -370,6 +379,7 @@ void nfs41_update_target_slotid(struct nfs4_slot_table *tbl, nfs41_set_target_slotid_locked(tbl, res->sr_target_highest_slotid); if (tbl->generation == slot->generation) nfs41_set_server_slotid_locked(tbl, res->sr_highest_slotid); + nfs41_set_max_slotid_locked(tbl, res->sr_target_highest_slotid); spin_unlock(&tbl->slot_tbl_lock); } -- 2.20.1