diff options
author | Roland Dreier <rolandd@cisco.com> | 2005-11-15 00:19:21 -0800 |
---|---|---|
committer | Roland Dreier <rolandd@cisco.com> | 2005-11-15 00:19:21 -0800 |
commit | 47f2bce9021b4974ed33b072ebb8348c8145c946 (patch) | |
tree | 2d17f2cdc77646d07cb2a598e3d2bcbdf94675ad | |
parent | 5f068992a1bccda5574b4f6d33458ef806686d7f (diff) | |
download | op-kernel-dev-47f2bce9021b4974ed33b072ebb8348c8145c946.zip op-kernel-dev-47f2bce9021b4974ed33b072ebb8348c8145c946.tar.gz |
[IB] srp: don't post receive if no send buf available
Have __srp_get_tx_iu() fail if the target port's request limit will
not allow the initiator to post a send. This avoids continuing on and
posting a receive, and then failing to post a corresponding send. If
that happens, then the initiator will end up with an extra receive
posted, and if this happens to much, the receive queue will overflow.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
-rw-r--r-- | drivers/infiniband/ulp/srp/ib_srp.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index a364530..ee9fe22 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -802,13 +802,21 @@ static int srp_post_recv(struct srp_target_port *target) /* * Must be called with target->scsi_host->host_lock held to protect - * req_lim and tx_head. + * req_lim and tx_head. Lock cannot be dropped between call here and + * call to __srp_post_send(). */ static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target) { if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE) return NULL; + if (unlikely(target->req_lim < 1)) { + if (printk_ratelimit()) + printk(KERN_DEBUG PFX "Target has req_lim %d\n", + target->req_lim); + return NULL; + } + return target->tx_ring[target->tx_head & SRP_SQ_SIZE]; } @@ -823,11 +831,6 @@ static int __srp_post_send(struct srp_target_port *target, struct ib_send_wr wr, *bad_wr; int ret = 0; - if (target->req_lim < 1) { - printk(KERN_ERR PFX "Target has req_lim %d\n", target->req_lim); - return -EAGAIN; - } - list.addr = iu->dma; list.length = len; list.lkey = target->srp_host->mr->lkey; |