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 <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4session.c b/fs/nfs/nfs4session.c
index ed5aa9f..1e6c87c 100644
--- a/fs/nfs/nfs4session.c
+++ b/fs/nfs/nfs4session.c
@@ -273,20 +273,28 @@
}
}
+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 @@
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 @@
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);
}