static inline enum comp_state check_psn(struct rxe_qp *qp,
struct rxe_pkt_info *pkt,
struct rxe_send_wqe *wqe)
{
s32 diff;
/* check to see if response is past the oldest WQE. if it is, complete
* send/write or error read/atomic
*/
diff = psn_compare(pkt->psn, wqe->last_psn);
if (diff > 0) {
if (wqe->state == wqe_state_pending) {
if (wqe->mask & WR_ATOMIC_OR_READ_MASK)
return COMPST_ERROR_RETRY;
reset_retry_counters(qp);
return COMPST_COMP_WQE;
} else {
return COMPST_DONE;
}
}
/* compare response packet to expected response */
diff = psn_compare(pkt->psn, qp->comp.psn);
if (diff < 0) {
/* response is most likely a retried packet if it matches an
* uncompleted WQE go complete it else ignore it
*/
if (pkt->psn == wqe->last_psn)
return COMPST_COMP_ACK;
else
return COMPST_DONE;
} else if ((diff > 0) && (wqe->mask & WR_ATOMIC_OR_READ_MASK)) {
return COMPST_DONE;
} else {
return COMPST_CHECK_ACK;
}
}
static inline enum comp_state complete_ack(struct rxe_qp *qp,
struct rxe_pkt_info *pkt,
struct rxe_send_wqe *wqe)
{
unsigned long flags;
if (wqe->has_rd_atomic) {
wqe->has_rd_atomic = 0;
atomic_inc(&qp->req.rd_atomic);
if (qp->req.need_rd_atomic) {
qp->comp.timeout_retry = 0;
qp->req.need_rd_atomic = 0;
rxe_run_task(&qp->req.task, 1);
}
}
if (unlikely(qp->req.state == QP_STATE_DRAIN)) {
/* state_lock used by requester & completer */
spin_lock_irqsave(&qp->state_lock, flags);
if ((qp->req.state == QP_STATE_DRAIN) &&
(qp->comp.psn == qp->req.psn)) {
qp->req.state = QP_STATE_DRAINED;
spin_unlock_irqrestore(&qp->state_lock, flags);
if (qp->ibqp.event_handler) {
struct ib_event ev;
ev.device = qp->ibqp.device;
ev.element.qp = &qp->ibqp;
ev.event = IB_EVENT_SQ_DRAINED;
qp->ibqp.event_handler(&ev,
qp->ibqp.qp_context);
}
} else {
spin_unlock_irqrestore(&qp->state_lock, flags);
}
}
do_complete(qp, wqe);
if (psn_compare(pkt->psn, qp->comp.psn) >= 0)
return COMPST_UPDATE_COMP;
else
return COMPST_DONE;
}
static enum resp_states check_psn(struct rxe_qp *qp,
struct rxe_pkt_info *pkt)
{
int diff = psn_compare(pkt->psn, qp->resp.psn);
struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
switch (qp_type(qp)) {
case IB_QPT_RC:
if (diff > 0) {
if (qp->resp.sent_psn_nak)
return RESPST_CLEANUP;
qp->resp.sent_psn_nak = 1;
rxe_counter_inc(rxe, RXE_CNT_OUT_OF_SEQ_REQ);
return RESPST_ERR_PSN_OUT_OF_SEQ;
} else if (diff < 0) {
rxe_counter_inc(rxe, RXE_CNT_DUP_REQ);
return RESPST_DUPLICATE_REQUEST;
}
if (qp->resp.sent_psn_nak)
qp->resp.sent_psn_nak = 0;
break;
case IB_QPT_UC:
if (qp->resp.drop_msg || diff != 0) {
if (pkt->mask & RXE_START_MASK) {
qp->resp.drop_msg = 0;
return RESPST_CHK_OP_SEQ;
}
qp->resp.drop_msg = 1;
return RESPST_CLEANUP;
}
break;
default:
break;
}
return RESPST_CHK_OP_SEQ;
}
static inline enum comp_state complete_wqe(struct rxe_qp *qp,
struct rxe_pkt_info *pkt,
struct rxe_send_wqe *wqe)
{
qp->comp.opcode = -1;
if (pkt) {
if (psn_compare(pkt->psn, qp->comp.psn) >= 0)
qp->comp.psn = (pkt->psn + 1) & BTH_PSN_MASK;
if (qp->req.wait_psn) {
qp->req.wait_psn = 0;
rxe_run_task(&qp->req.task, 1);
}
}
do_complete(qp, wqe);
return COMPST_GET_WQE;
}
/* RDMA read response. If res is not NULL, then we have a current RDMA request
* being processed or replayed.
*/
static enum resp_states read_reply(struct rxe_qp *qp,
struct rxe_pkt_info *req_pkt)
{
struct rxe_pkt_info ack_pkt;
struct sk_buff *skb;
int mtu = qp->mtu;
enum resp_states state;
int payload;
int opcode;
int err;
struct resp_res *res = qp->resp.res;
u32 icrc;
u32 *p;
if (!res) {
/* This is the first time we process that request. Get a
* resource
*/
res = &qp->resp.resources[qp->resp.res_head];
free_rd_atomic_resource(qp, res);
rxe_advance_resp_resource(qp);
res->type = RXE_READ_MASK;
res->replay = 0;
res->read.va = qp->resp.va;
res->read.va_org = qp->resp.va;
res->first_psn = req_pkt->psn;
if (reth_len(req_pkt)) {
res->last_psn = (req_pkt->psn +
(reth_len(req_pkt) + mtu - 1) /
mtu - 1) & BTH_PSN_MASK;
} else {
res->last_psn = res->first_psn;
}
res->cur_psn = req_pkt->psn;
res->read.resid = qp->resp.resid;
res->read.length = qp->resp.resid;
res->read.rkey = qp->resp.rkey;
/* note res inherits the reference to mr from qp */
res->read.mr = qp->resp.mr;
qp->resp.mr = NULL;
qp->resp.res = res;
res->state = rdatm_res_state_new;
}
if (res->state == rdatm_res_state_new) {
if (res->read.resid <= mtu)
opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY;
else
opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST;
} else {
if (res->read.resid > mtu)
opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE;
else
opcode = IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST;
}
res->state = rdatm_res_state_next;
payload = min_t(int, res->read.resid, mtu);
skb = prepare_ack_packet(qp, req_pkt, &ack_pkt, opcode, payload,
res->cur_psn, AETH_ACK_UNLIMITED, &icrc);
if (!skb)
return RESPST_ERR_RNR;
err = rxe_mem_copy(res->read.mr, res->read.va, payload_addr(&ack_pkt),
payload, from_mem_obj, &icrc);
if (err)
pr_err("Failed copying memory\n");
p = payload_addr(&ack_pkt) + payload + bth_pad(&ack_pkt);
*p = ~icrc;
err = rxe_xmit_packet(qp, &ack_pkt, skb);
if (err) {
pr_err("Failed sending RDMA reply.\n");
return RESPST_ERR_RNR;
}
res->read.va += payload;
res->read.resid -= payload;
res->cur_psn = (res->cur_psn + 1) & BTH_PSN_MASK;
if (res->read.resid > 0) {
state = RESPST_DONE;
} else {
qp->resp.res = NULL;
if (!res->replay)
qp->resp.opcode = -1;
if (psn_compare(res->cur_psn, qp->resp.psn) >= 0)
qp->resp.psn = res->cur_psn;
state = RESPST_CLEANUP;
}
return state;
}
int rxe_completer(void *arg)
{
struct rxe_qp *qp = (struct rxe_qp *)arg;
struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
struct rxe_send_wqe *wqe = wqe;
struct sk_buff *skb = NULL;
struct rxe_pkt_info *pkt = NULL;
enum comp_state state;
rxe_add_ref(qp);
if (!qp->valid || qp->req.state == QP_STATE_ERROR ||
qp->req.state == QP_STATE_RESET) {
rxe_drain_resp_pkts(qp, qp->valid &&
qp->req.state == QP_STATE_ERROR);
goto exit;
}
if (qp->comp.timeout) {
qp->comp.timeout_retry = 1;
qp->comp.timeout = 0;
} else {
qp->comp.timeout_retry = 0;
}
if (qp->req.need_retry)
goto exit;
state = COMPST_GET_ACK;
while (1) {
pr_debug("qp#%d state = %s\n", qp_num(qp),
comp_state_name[state]);
switch (state) {
case COMPST_GET_ACK:
skb = skb_dequeue(&qp->resp_pkts);
if (skb) {
pkt = SKB_TO_PKT(skb);
qp->comp.timeout_retry = 0;
}
state = COMPST_GET_WQE;
break;
case COMPST_GET_WQE:
state = get_wqe(qp, pkt, &wqe);
break;
case COMPST_CHECK_PSN:
state = check_psn(qp, pkt, wqe);
break;
case COMPST_CHECK_ACK:
state = check_ack(qp, pkt, wqe);
break;
case COMPST_READ:
state = do_read(qp, pkt, wqe);
break;
case COMPST_ATOMIC:
state = do_atomic(qp, pkt, wqe);
break;
case COMPST_WRITE_SEND:
if (wqe->state == wqe_state_pending &&
wqe->last_psn == pkt->psn)
state = COMPST_COMP_ACK;
else
state = COMPST_UPDATE_COMP;
break;
case COMPST_COMP_ACK:
state = complete_ack(qp, pkt, wqe);
break;
case COMPST_COMP_WQE:
state = complete_wqe(qp, pkt, wqe);
break;
case COMPST_UPDATE_COMP:
if (pkt->mask & RXE_END_MASK)
qp->comp.opcode = -1;
else
qp->comp.opcode = pkt->opcode;
if (psn_compare(pkt->psn, qp->comp.psn) >= 0)
qp->comp.psn = (pkt->psn + 1) & BTH_PSN_MASK;
if (qp->req.wait_psn) {
qp->req.wait_psn = 0;
rxe_run_task(&qp->req.task, 1);
}
state = COMPST_DONE;
break;
case COMPST_DONE:
if (pkt) {
rxe_drop_ref(pkt->qp);
kfree_skb(skb);
skb = NULL;
}
goto done;
case COMPST_EXIT:
if (qp->comp.timeout_retry && wqe) {
state = COMPST_ERROR_RETRY;
break;
}
/* re reset the timeout counter if
* (1) QP is type RC
* (2) the QP is alive
* (3) there is a packet sent by the requester that
* might be acked (we still might get spurious
* timeouts but try to keep them as few as possible)
* (4) the timeout parameter is set
*/
if ((qp_type(qp) == IB_QPT_RC) &&
(qp->req.state == QP_STATE_READY) &&
(psn_compare(qp->req.psn, qp->comp.psn) > 0) &&
qp->qp_timeout_jiffies)
mod_timer(&qp->retrans_timer,
jiffies + qp->qp_timeout_jiffies);
WARN_ON_ONCE(skb);
goto exit;
case COMPST_ERROR_RETRY:
/* we come here if the retry timer fired and we did
* not receive a response packet. try to retry the send
* queue if that makes sense and the limits have not
* been exceeded. remember that some timeouts are
* spurious since we do not reset the timer but kick
* it down the road or let it expire
*/
/* there is nothing to retry in this case */
if (!wqe || (wqe->state == wqe_state_posted)) {
WARN_ON_ONCE(skb);
goto exit;
}
if (qp->comp.retry_cnt > 0) {
if (qp->comp.retry_cnt != 7)
qp->comp.retry_cnt--;
/* no point in retrying if we have already
* seen the last ack that the requester could
* have caused
*/
if (psn_compare(qp->req.psn,
qp->comp.psn) > 0) {
/* tell the requester to retry the
* send queue next time around
*/
rxe_counter_inc(rxe,
RXE_CNT_COMP_RETRY);
qp->req.need_retry = 1;
rxe_run_task(&qp->req.task, 1);
}
if (pkt) {
rxe_drop_ref(pkt->qp);
kfree_skb(skb);
skb = NULL;
}
WARN_ON_ONCE(skb);
goto exit;
} else {
rxe_counter_inc(rxe, RXE_CNT_RETRY_EXCEEDED);
wqe->status = IB_WC_RETRY_EXC_ERR;
state = COMPST_ERROR;
}
break;
case COMPST_RNR_RETRY:
if (qp->comp.rnr_retry > 0) {
if (qp->comp.rnr_retry != 7)
qp->comp.rnr_retry--;
qp->req.need_retry = 1;
pr_debug("qp#%d set rnr nak timer\n",
qp_num(qp));
mod_timer(&qp->rnr_nak_timer,
jiffies + rnrnak_jiffies(aeth_syn(pkt)
& ~AETH_TYPE_MASK));
rxe_drop_ref(pkt->qp);
kfree_skb(skb);
skb = NULL;
goto exit;
} else {
rxe_counter_inc(rxe,
RXE_CNT_RNR_RETRY_EXCEEDED);
wqe->status = IB_WC_RNR_RETRY_EXC_ERR;
state = COMPST_ERROR;
}
break;
case COMPST_ERROR:
WARN_ON_ONCE(wqe->status == IB_WC_SUCCESS);
do_complete(qp, wqe);
rxe_qp_error(qp);
if (pkt) {
rxe_drop_ref(pkt->qp);
kfree_skb(skb);
skb = NULL;
}
WARN_ON_ONCE(skb);
goto exit;
}
}
exit:
/* we come here if we are done with processing and want the task to
* exit from the loop calling us
*/
WARN_ON_ONCE(skb);
rxe_drop_ref(qp);
return -EAGAIN;
done:
/* we come here if we have processed a packet we want the task to call
* us again to see if there is anything else to do
*/
WARN_ON_ONCE(skb);
rxe_drop_ref(qp);
return 0;
}
static inline enum comp_state check_ack(struct rxe_qp *qp,
struct rxe_pkt_info *pkt,
struct rxe_send_wqe *wqe)
{
unsigned int mask = pkt->mask;
u8 syn;
struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
/* Check the sequence only */
switch (qp->comp.opcode) {
case -1:
/* Will catch all *_ONLY cases. */
if (!(mask & RXE_START_MASK))
return COMPST_ERROR;
break;
case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST:
case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE:
if (pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE &&
pkt->opcode != IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST) {
return COMPST_ERROR;
}
break;
default:
WARN_ON_ONCE(1);
}
/* Check operation validity. */
switch (pkt->opcode) {
case IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST:
case IB_OPCODE_RC_RDMA_READ_RESPONSE_LAST:
case IB_OPCODE_RC_RDMA_READ_RESPONSE_ONLY:
syn = aeth_syn(pkt);
if ((syn & AETH_TYPE_MASK) != AETH_ACK)
return COMPST_ERROR;
/* Fall through (IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE
* doesn't have an AETH)
*/
case IB_OPCODE_RC_RDMA_READ_RESPONSE_MIDDLE:
if (wqe->wr.opcode != IB_WR_RDMA_READ &&
wqe->wr.opcode != IB_WR_RDMA_READ_WITH_INV) {
return COMPST_ERROR;
}
reset_retry_counters(qp);
return COMPST_READ;
case IB_OPCODE_RC_ATOMIC_ACKNOWLEDGE:
syn = aeth_syn(pkt);
if ((syn & AETH_TYPE_MASK) != AETH_ACK)
return COMPST_ERROR;
if (wqe->wr.opcode != IB_WR_ATOMIC_CMP_AND_SWP &&
wqe->wr.opcode != IB_WR_ATOMIC_FETCH_AND_ADD)
return COMPST_ERROR;
reset_retry_counters(qp);
return COMPST_ATOMIC;
case IB_OPCODE_RC_ACKNOWLEDGE:
syn = aeth_syn(pkt);
switch (syn & AETH_TYPE_MASK) {
case AETH_ACK:
reset_retry_counters(qp);
return COMPST_WRITE_SEND;
case AETH_RNR_NAK:
rxe_counter_inc(rxe, RXE_CNT_RCV_RNR);
return COMPST_RNR_RETRY;
case AETH_NAK:
switch (syn) {
case AETH_NAK_PSN_SEQ_ERROR:
/* a nak implicitly acks all packets with psns
* before
*/
if (psn_compare(pkt->psn, qp->comp.psn) > 0) {
rxe_counter_inc(rxe,
RXE_CNT_RCV_SEQ_ERR);
qp->comp.psn = pkt->psn;
if (qp->req.wait_psn) {
qp->req.wait_psn = 0;
rxe_run_task(&qp->req.task, 1);
}
}
return COMPST_ERROR_RETRY;
case AETH_NAK_INVALID_REQ:
wqe->status = IB_WC_REM_INV_REQ_ERR;
return COMPST_ERROR;
case AETH_NAK_REM_ACC_ERR:
wqe->status = IB_WC_REM_ACCESS_ERR;
return COMPST_ERROR;
case AETH_NAK_REM_OP_ERR:
wqe->status = IB_WC_REM_OP_ERR;
return COMPST_ERROR;
default:
pr_warn("unexpected nak %x\n", syn);
wqe->status = IB_WC_REM_OP_ERR;
return COMPST_ERROR;
}
default:
return COMPST_ERROR;
}
break;
default:
pr_warn("unexpected opcode\n");
}
return COMPST_ERROR;
}
