IB/qib: Fix race between qib_error_qp() and receive packet processing

[pandora-kernel.git] / drivers / infiniband / hw / qib / qib_rc.c

diff --git a/drivers/infiniband/hw/qib/qib_rc.c b/drivers/infiniband/hw/qib/qib_rc.c
index 40c0a37..a093111 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_rc.c
+++ b/drivers/infiniband/hw/qib/qib_rc.c
@@ -868,7 +868,7 @@ done:
 
 /*
  * Back up requester to resend the last un-ACKed request.
- * The QP s_lock should be held and interrupts disabled.
+ * The QP r_lock and s_lock should be held and interrupts disabled.
  */
 static void qib_restart_rc(struct qib_qp *qp, u32 psn, int wait)
 {
@@ -911,7 +911,8 @@ static void rc_timeout(unsigned long arg)
        struct qib_ibport *ibp;
        unsigned long flags;
 
-       spin_lock_irqsave(&qp->s_lock, flags);
+       spin_lock_irqsave(&qp->r_lock, flags);
+       spin_lock(&qp->s_lock);
        if (qp->s_flags & QIB_S_TIMER) {
                ibp = to_iport(qp->ibqp.device, qp->port_num);
                ibp->n_rc_timeouts++;
@@ -920,7 +921,8 @@ static void rc_timeout(unsigned long arg)
                qib_restart_rc(qp, qp->s_last_psn + 1, 1);
                qib_schedule_send(qp);
        }
-       spin_unlock_irqrestore(&qp->s_lock, flags);
+       spin_unlock(&qp->s_lock);
+       spin_unlock_irqrestore(&qp->r_lock, flags);
 }
 
 /*
@@ -1414,10 +1416,6 @@ static void qib_rc_rcv_resp(struct qib_ibport *ibp,
 
        spin_lock_irqsave(&qp->s_lock, flags);
 
-       /* Double check we can process this now that we hold the s_lock. */
-       if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK))
-               goto ack_done;
-
        /* Ignore invalid responses. */
        if (qib_cmp24(psn, qp->s_next_psn) >= 0)
                goto ack_done;
@@ -1661,9 +1659,6 @@ static int qib_rc_rcv_error(struct qib_other_headers *ohdr,
        ibp->n_rc_dupreq++;
 
        spin_lock_irqsave(&qp->s_lock, flags);
-       /* Double check we can process this now that we hold the s_lock. */
-       if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK))
-               goto unlock_done;
 
        for (i = qp->r_head_ack_queue; ; i = prev) {
                if (i == qp->s_tail_ack_queue)
@@ -1878,9 +1873,6 @@ void qib_rc_rcv(struct qib_ctxtdata *rcd, struct qib_ib_header *hdr,
        psn = be32_to_cpu(ohdr->bth[2]);
        opcode >>= 24;
 
-       /* Prevent simultaneous processing after APM on different CPUs */
-       spin_lock(&qp->r_lock);
-
        /*
         * Process responses (ACKs) before anything else.  Note that the
         * packet sequence number will be for something in the send work
@@ -1891,14 +1883,14 @@ void qib_rc_rcv(struct qib_ctxtdata *rcd, struct qib_ib_header *hdr,
            opcode <= OP(ATOMIC_ACKNOWLEDGE)) {
                qib_rc_rcv_resp(ibp, ohdr, data, tlen, qp, opcode, psn,
                                hdrsize, pmtu, rcd);
-               goto runlock;
+               return;
        }
 
        /* Compute 24 bits worth of difference. */
        diff = qib_cmp24(psn, qp->r_psn);
        if (unlikely(diff)) {
                if (qib_rc_rcv_error(ohdr, data, qp, opcode, psn, diff, rcd))
-                       goto runlock;
+                       return;
                goto send_ack;
        }
 
@@ -2090,9 +2082,6 @@ send_last:
                if (next > QIB_MAX_RDMA_ATOMIC)
                        next = 0;
                spin_lock_irqsave(&qp->s_lock, flags);
-               /* Double check we can process this while holding the s_lock. */
-               if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK))
-                       goto srunlock;
                if (unlikely(next == qp->s_tail_ack_queue)) {
                        if (!qp->s_ack_queue[next].sent)
                                goto nack_inv_unlck;
@@ -2146,7 +2135,7 @@ send_last:
                qp->s_flags |= QIB_S_RESP_PENDING;
                qib_schedule_send(qp);
 
-               goto srunlock;
+               goto sunlock;
        }
 
        case OP(COMPARE_SWAP):
@@ -2165,9 +2154,6 @@ send_last:
                if (next > QIB_MAX_RDMA_ATOMIC)
                        next = 0;
                spin_lock_irqsave(&qp->s_lock, flags);
-               /* Double check we can process this while holding the s_lock. */
-               if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK))
-                       goto srunlock;
                if (unlikely(next == qp->s_tail_ack_queue)) {
                        if (!qp->s_ack_queue[next].sent)
                                goto nack_inv_unlck;
@@ -2213,7 +2199,7 @@ send_last:
                qp->s_flags |= QIB_S_RESP_PENDING;
                qib_schedule_send(qp);
 
-               goto srunlock;
+               goto sunlock;
        }
 
        default:
@@ -2227,7 +2213,7 @@ send_last:
        /* Send an ACK if requested or required. */
        if (psn & (1 << 31))
                goto send_ack;
-       goto runlock;
+       return;
 
 rnr_nak:
        qp->r_nak_state = IB_RNR_NAK | qp->r_min_rnr_timer;
@@ -2238,7 +2224,7 @@ rnr_nak:
                atomic_inc(&qp->refcount);
                list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
        }
-       goto runlock;
+       return;
 
 nack_op_err:
        qib_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
@@ -2250,7 +2236,7 @@ nack_op_err:
                atomic_inc(&qp->refcount);
                list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
        }
-       goto runlock;
+       return;
 
 nack_inv_unlck:
        spin_unlock_irqrestore(&qp->s_lock, flags);
@@ -2264,7 +2250,7 @@ nack_inv:
                atomic_inc(&qp->refcount);
                list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
        }
-       goto runlock;
+       return;
 
 nack_acc_unlck:
        spin_unlock_irqrestore(&qp->s_lock, flags);
@@ -2274,13 +2260,6 @@ nack_acc:
        qp->r_ack_psn = qp->r_psn;
 send_ack:
        qib_send_rc_ack(qp);
-runlock:
-       spin_unlock(&qp->r_lock);
-       return;
-
-srunlock:
-       spin_unlock_irqrestore(&qp->s_lock, flags);
-       spin_unlock(&qp->r_lock);
        return;
 
 sunlock: