RDMA/nes: Multiple disconnects cause crash during AE handling

There is a double disconnect during AE processing, causing crashes.
While fixing the crash, also simplify the AE handling code.

Signed-off-by: Faisal Latif <faisal.latif@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 28 insertions, 60 deletions

diff --git a/drivers/infiniband/hw/nes/nes_hw.c b/drivers/infiniband/hw/nes/nes_hw.c
index b1c2cbb88f09..310cc7cab396 100644
--- a/drivers/infiniband/hw/nes/nes_hw.c
+++ b/drivers/infiniband/hw/nes/nes_hw.c
@@ -3352,8 +3352,6 @@ static void nes_process_iwarp_aeqe(struct nes_device *nesdev,
         u16 async_event_id;
         u8 tcp_state;
         u8 iwarp_state;
-        int must_disconn = 1;
-        int must_terminate = 0;
         struct ib_event ibevent;
 
         nes_debug(NES_DBG_AEQ, "\n");
@@ -3367,6 +3365,8 @@ static void nes_process_iwarp_aeqe(struct nes_device *nesdev,
                 BUG_ON(!context);
         }
 
+        /* context is nesqp unless async_event_id == CQ ERROR */
+        nesqp = (struct nes_qp *)(unsigned long)context;
         async_event_id = (u16)aeq_info;
         tcp_state = (aeq_info & NES_AEQE_TCP_STATE_MASK) >> NES_AEQE_TCP_STATE_SHIFT;
         iwarp_state = (aeq_info & NES_AEQE_IWARP_STATE_MASK) >> NES_AEQE_IWARP_STATE_SHIFT;
@@ -3378,8 +3378,6 @@ static void nes_process_iwarp_aeqe(struct nes_device *nesdev,
 
         switch (async_event_id) {
                 case NES_AEQE_AEID_LLP_FIN_RECEIVED:
-                        nesqp = (struct nes_qp *)(unsigned long)context;
-
                         if (nesqp->term_flags)
                                 return; /* Ignore it, wait for close complete */
 
@@ -3394,79 +3392,48 @@ static void nes_process_iwarp_aeqe(struct nes_device *nesdev,
                                                 async_event_id, nesqp->last_aeq, tcp_state);
                         }
 
-                        if ((tcp_state != NES_AEQE_TCP_STATE_CLOSE_WAIT) ||
-                                        (nesqp->ibqp_state != IB_QPS_RTS)) {
-                                /* FIN Received but tcp state or IB state moved on,
-                                                should expect a close complete */
-                                return;
-                        }
-
+                        break;
                 case NES_AEQE_AEID_LLP_CLOSE_COMPLETE:
-                        nesqp = (struct nes_qp *)(unsigned long)context;
                         if (nesqp->term_flags) {
                                 nes_terminate_done(nesqp, 0);
                                 return;
                         }
+                        spin_lock_irqsave(&nesqp->lock, flags);
+                        nesqp->hw_iwarp_state = NES_AEQE_IWARP_STATE_CLOSING;
+                        spin_unlock_irqrestore(&nesqp->lock, flags);
+                        nes_hw_modify_qp(nesdev, nesqp, NES_CQP_QP_IWARP_STATE_CLOSING, 0, 0);
+                        nes_cm_disconn(nesqp);
+                        break;
 
-                case NES_AEQE_AEID_LLP_CONNECTION_RESET:
                 case NES_AEQE_AEID_RESET_SENT:
-                        nesqp = (struct nes_qp *)(unsigned long)context;
-                        if (async_event_id == NES_AEQE_AEID_RESET_SENT) {
-                                tcp_state = NES_AEQE_TCP_STATE_CLOSED;
-                        }
+                        tcp_state = NES_AEQE_TCP_STATE_CLOSED;
                         spin_lock_irqsave(&nesqp->lock, flags);
                         nesqp->hw_iwarp_state = iwarp_state;
                         nesqp->hw_tcp_state = tcp_state;
                         nesqp->last_aeq = async_event_id;
-
-                        if ((tcp_state == NES_AEQE_TCP_STATE_CLOSED) ||
-                                        (tcp_state == NES_AEQE_TCP_STATE_TIME_WAIT)) {
-                                nesqp->hte_added = 0;
-                                next_iwarp_state = NES_CQP_QP_IWARP_STATE_ERROR | NES_CQP_QP_DEL_HTE;
-                        }
-
-                        if ((nesqp->ibqp_state == IB_QPS_RTS) &&
-                                        ((tcp_state == NES_AEQE_TCP_STATE_CLOSE_WAIT) ||
-                                        (async_event_id == NES_AEQE_AEID_LLP_CONNECTION_RESET))) {
-                                switch (nesqp->hw_iwarp_state) {
-                                        case NES_AEQE_IWARP_STATE_RTS:
-                                                next_iwarp_state = NES_CQP_QP_IWARP_STATE_CLOSING;
-                                                nesqp->hw_iwarp_state = NES_AEQE_IWARP_STATE_CLOSING;
-                                                break;
-                                        case NES_AEQE_IWARP_STATE_TERMINATE:
-                                                must_disconn = 0; /* terminate path takes care of disconn */
-                                                if (nesqp->term_flags == 0)
-                                                        must_terminate = 1;
-                                                break;
-                                }
-                        } else {
-                                if (async_event_id ==  NES_AEQE_AEID_LLP_FIN_RECEIVED) {
-                                        /* FIN Received but ib state not RTS,
-                                                        close complete will be on its way */
-                                        must_disconn = 0;
-                                }
-                        }
+                        nesqp->hte_added = 0;
                         spin_unlock_irqrestore(&nesqp->lock, flags);
+                        next_iwarp_state = NES_CQP_QP_IWARP_STATE_ERROR | NES_CQP_QP_DEL_HTE;
+                        nes_hw_modify_qp(nesdev, nesqp, next_iwarp_state, 0, 0);
+                        nes_cm_disconn(nesqp);
+                        break;
 
-                        if (must_terminate)
-                                nes_terminate_connection(nesdev, nesqp, aeqe, IB_EVENT_QP_FATAL);
-                        else if (must_disconn) {
-                                if (next_iwarp_state) {
-                                        nes_debug(NES_DBG_AEQ, "issuing hw modifyqp for QP%u. next state = 0x%08X\n",
-                                                  nesqp->hwqp.qp_id, next_iwarp_state);
-                                        nes_hw_modify_qp(nesdev, nesqp, next_iwarp_state, 0, 0);
-                                }
-                                nes_cm_disconn(nesqp);
-                        }
+                case NES_AEQE_AEID_LLP_CONNECTION_RESET:
+                        if (atomic_read(&nesqp->close_timer_started))
+                                return;
+                        spin_lock_irqsave(&nesqp->lock, flags);
+                        nesqp->hw_iwarp_state = iwarp_state;
+                        nesqp->hw_tcp_state = tcp_state;
+                        nesqp->last_aeq = async_event_id;
+                        spin_unlock_irqrestore(&nesqp->lock, flags);
+                        nes_cm_disconn(nesqp);
                         break;
 
                 case NES_AEQE_AEID_TERMINATE_SENT:
-                        nesqp = (struct nes_qp *)(unsigned long)context;
                         nes_terminate_send_fin(nesdev, nesqp, aeqe);
                         break;
 
                 case NES_AEQE_AEID_LLP_TERMINATE_RECEIVED:
-                        nesqp = (struct nes_qp *)(unsigned long)context;
                         nes_terminate_received(nesdev, nesqp, aeqe);
                         break;
 
@@ -3480,7 +3447,8 @@ static void nes_process_iwarp_aeqe(struct nes_device *nesdev,
                 case NES_AEQE_AEID_DDP_UBE_DDP_MESSAGE_TOO_LONG_FOR_AVAILABLE_BUFFER:
                 case NES_AEQE_AEID_AMP_BOUNDS_VIOLATION:
                 case NES_AEQE_AEID_AMP_TO_WRAP:
-                        nesqp = (struct nes_qp *)(unsigned long)context;
+                        printk(KERN_ERR PFX "QP[%u] async_event_id=0x%04X IB_EVENT_QP_ACCESS_ERR\n",
+                                        nesqp->hwqp.qp_id, async_event_id);
                         nes_terminate_connection(nesdev, nesqp, aeqe, IB_EVENT_QP_ACCESS_ERR);
                         break;
 
@@ -3488,7 +3456,6 @@ static void nes_process_iwarp_aeqe(struct nes_device *nesdev,
                 case NES_AEQE_AEID_LLP_SEGMENT_TOO_SMALL:
                 case NES_AEQE_AEID_DDP_UBE_INVALID_MO:
                 case NES_AEQE_AEID_DDP_UBE_INVALID_QN:
-                        nesqp = (struct nes_qp *)(unsigned long)context;
                         if (iwarp_opcode(nesqp, aeq_info) > IWARP_OPCODE_TERM) {
                                 aeq_info &= 0xffff0000;
                                 aeq_info |= NES_AEQE_AEID_RDMAP_ROE_UNEXPECTED_OPCODE;
@@ -3530,7 +3497,8 @@ static void nes_process_iwarp_aeqe(struct nes_device *nesdev,
                 case NES_AEQE_AEID_STAG_ZERO_INVALID:
                 case NES_AEQE_AEID_ROE_INVALID_RDMA_READ_REQUEST:
                 case NES_AEQE_AEID_ROE_INVALID_RDMA_WRITE_OR_READ_RESP:
-                        nesqp = (struct nes_qp *)(unsigned long)context;
+                        printk(KERN_ERR PFX "QP[%u] async_event_id=0x%04X IB_EVENT_QP_FATAL\n",
+                                        nesqp->hwqp.qp_id, async_event_id);
                         nes_terminate_connection(nesdev, nesqp, aeqe, IB_EVENT_QP_FATAL);
                         break;