Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / infiniband / hw / cxgb4 / cq.c
diff --git a/kernel/drivers/infiniband/hw/cxgb4/cq.c b/kernel/drivers/infiniband/hw/cxgb4/cq.c
new file mode 100644 (file)
index 0000000..68ddb37
--- /dev/null
@@ -0,0 +1,1015 @@
+/*
+ * Copyright (c) 2009-2010 Chelsio, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer in the documentation and/or other materials
+ *       provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "iw_cxgb4.h"
+
+static int destroy_cq(struct c4iw_rdev *rdev, struct t4_cq *cq,
+                     struct c4iw_dev_ucontext *uctx)
+{
+       struct fw_ri_res_wr *res_wr;
+       struct fw_ri_res *res;
+       int wr_len;
+       struct c4iw_wr_wait wr_wait;
+       struct sk_buff *skb;
+       int ret;
+
+       wr_len = sizeof *res_wr + sizeof *res;
+       skb = alloc_skb(wr_len, GFP_KERNEL);
+       if (!skb)
+               return -ENOMEM;
+       set_wr_txq(skb, CPL_PRIORITY_CONTROL, 0);
+
+       res_wr = (struct fw_ri_res_wr *)__skb_put(skb, wr_len);
+       memset(res_wr, 0, wr_len);
+       res_wr->op_nres = cpu_to_be32(
+                       FW_WR_OP_V(FW_RI_RES_WR) |
+                       FW_RI_RES_WR_NRES_V(1) |
+                       FW_WR_COMPL_F);
+       res_wr->len16_pkd = cpu_to_be32(DIV_ROUND_UP(wr_len, 16));
+       res_wr->cookie = (uintptr_t)&wr_wait;
+       res = res_wr->res;
+       res->u.cq.restype = FW_RI_RES_TYPE_CQ;
+       res->u.cq.op = FW_RI_RES_OP_RESET;
+       res->u.cq.iqid = cpu_to_be32(cq->cqid);
+
+       c4iw_init_wr_wait(&wr_wait);
+       ret = c4iw_ofld_send(rdev, skb);
+       if (!ret) {
+               ret = c4iw_wait_for_reply(rdev, &wr_wait, 0, 0, __func__);
+       }
+
+       kfree(cq->sw_queue);
+       dma_free_coherent(&(rdev->lldi.pdev->dev),
+                         cq->memsize, cq->queue,
+                         dma_unmap_addr(cq, mapping));
+       c4iw_put_cqid(rdev, cq->cqid, uctx);
+       return ret;
+}
+
+static int create_cq(struct c4iw_rdev *rdev, struct t4_cq *cq,
+                    struct c4iw_dev_ucontext *uctx)
+{
+       struct fw_ri_res_wr *res_wr;
+       struct fw_ri_res *res;
+       int wr_len;
+       int user = (uctx != &rdev->uctx);
+       struct c4iw_wr_wait wr_wait;
+       int ret;
+       struct sk_buff *skb;
+
+       cq->cqid = c4iw_get_cqid(rdev, uctx);
+       if (!cq->cqid) {
+               ret = -ENOMEM;
+               goto err1;
+       }
+
+       if (!user) {
+               cq->sw_queue = kzalloc(cq->memsize, GFP_KERNEL);
+               if (!cq->sw_queue) {
+                       ret = -ENOMEM;
+                       goto err2;
+               }
+       }
+       cq->queue = dma_alloc_coherent(&rdev->lldi.pdev->dev, cq->memsize,
+                                      &cq->dma_addr, GFP_KERNEL);
+       if (!cq->queue) {
+               ret = -ENOMEM;
+               goto err3;
+       }
+       dma_unmap_addr_set(cq, mapping, cq->dma_addr);
+       memset(cq->queue, 0, cq->memsize);
+
+       /* build fw_ri_res_wr */
+       wr_len = sizeof *res_wr + sizeof *res;
+
+       skb = alloc_skb(wr_len, GFP_KERNEL);
+       if (!skb) {
+               ret = -ENOMEM;
+               goto err4;
+       }
+       set_wr_txq(skb, CPL_PRIORITY_CONTROL, 0);
+
+       res_wr = (struct fw_ri_res_wr *)__skb_put(skb, wr_len);
+       memset(res_wr, 0, wr_len);
+       res_wr->op_nres = cpu_to_be32(
+                       FW_WR_OP_V(FW_RI_RES_WR) |
+                       FW_RI_RES_WR_NRES_V(1) |
+                       FW_WR_COMPL_F);
+       res_wr->len16_pkd = cpu_to_be32(DIV_ROUND_UP(wr_len, 16));
+       res_wr->cookie = (uintptr_t)&wr_wait;
+       res = res_wr->res;
+       res->u.cq.restype = FW_RI_RES_TYPE_CQ;
+       res->u.cq.op = FW_RI_RES_OP_WRITE;
+       res->u.cq.iqid = cpu_to_be32(cq->cqid);
+       res->u.cq.iqandst_to_iqandstindex = cpu_to_be32(
+                       FW_RI_RES_WR_IQANUS_V(0) |
+                       FW_RI_RES_WR_IQANUD_V(1) |
+                       FW_RI_RES_WR_IQANDST_F |
+                       FW_RI_RES_WR_IQANDSTINDEX_V(
+                               rdev->lldi.ciq_ids[cq->vector]));
+       res->u.cq.iqdroprss_to_iqesize = cpu_to_be16(
+                       FW_RI_RES_WR_IQDROPRSS_F |
+                       FW_RI_RES_WR_IQPCIECH_V(2) |
+                       FW_RI_RES_WR_IQINTCNTTHRESH_V(0) |
+                       FW_RI_RES_WR_IQO_F |
+                       FW_RI_RES_WR_IQESIZE_V(1));
+       res->u.cq.iqsize = cpu_to_be16(cq->size);
+       res->u.cq.iqaddr = cpu_to_be64(cq->dma_addr);
+
+       c4iw_init_wr_wait(&wr_wait);
+
+       ret = c4iw_ofld_send(rdev, skb);
+       if (ret)
+               goto err4;
+       PDBG("%s wait_event wr_wait %p\n", __func__, &wr_wait);
+       ret = c4iw_wait_for_reply(rdev, &wr_wait, 0, 0, __func__);
+       if (ret)
+               goto err4;
+
+       cq->gen = 1;
+       cq->rdev = rdev;
+       if (user) {
+               u32 off = (cq->cqid << rdev->cqshift) & PAGE_MASK;
+
+               cq->ugts = (u64)rdev->bar2_pa + off;
+       } else if (is_t4(rdev->lldi.adapter_type)) {
+               cq->gts = rdev->lldi.gts_reg;
+               cq->qid_mask = -1U;
+       } else {
+               u32 off = ((cq->cqid << rdev->cqshift) & PAGE_MASK) + 12;
+
+               cq->gts = rdev->bar2_kva + off;
+               cq->qid_mask = rdev->qpmask;
+       }
+       return 0;
+err4:
+       dma_free_coherent(&rdev->lldi.pdev->dev, cq->memsize, cq->queue,
+                         dma_unmap_addr(cq, mapping));
+err3:
+       kfree(cq->sw_queue);
+err2:
+       c4iw_put_cqid(rdev, cq->cqid, uctx);
+err1:
+       return ret;
+}
+
+static void insert_recv_cqe(struct t4_wq *wq, struct t4_cq *cq)
+{
+       struct t4_cqe cqe;
+
+       PDBG("%s wq %p cq %p sw_cidx %u sw_pidx %u\n", __func__,
+            wq, cq, cq->sw_cidx, cq->sw_pidx);
+       memset(&cqe, 0, sizeof(cqe));
+       cqe.header = cpu_to_be32(CQE_STATUS_V(T4_ERR_SWFLUSH) |
+                                CQE_OPCODE_V(FW_RI_SEND) |
+                                CQE_TYPE_V(0) |
+                                CQE_SWCQE_V(1) |
+                                CQE_QPID_V(wq->sq.qid));
+       cqe.bits_type_ts = cpu_to_be64(CQE_GENBIT_V((u64)cq->gen));
+       cq->sw_queue[cq->sw_pidx] = cqe;
+       t4_swcq_produce(cq);
+}
+
+int c4iw_flush_rq(struct t4_wq *wq, struct t4_cq *cq, int count)
+{
+       int flushed = 0;
+       int in_use = wq->rq.in_use - count;
+
+       BUG_ON(in_use < 0);
+       PDBG("%s wq %p cq %p rq.in_use %u skip count %u\n", __func__,
+            wq, cq, wq->rq.in_use, count);
+       while (in_use--) {
+               insert_recv_cqe(wq, cq);
+               flushed++;
+       }
+       return flushed;
+}
+
+static void insert_sq_cqe(struct t4_wq *wq, struct t4_cq *cq,
+                         struct t4_swsqe *swcqe)
+{
+       struct t4_cqe cqe;
+
+       PDBG("%s wq %p cq %p sw_cidx %u sw_pidx %u\n", __func__,
+            wq, cq, cq->sw_cidx, cq->sw_pidx);
+       memset(&cqe, 0, sizeof(cqe));
+       cqe.header = cpu_to_be32(CQE_STATUS_V(T4_ERR_SWFLUSH) |
+                                CQE_OPCODE_V(swcqe->opcode) |
+                                CQE_TYPE_V(1) |
+                                CQE_SWCQE_V(1) |
+                                CQE_QPID_V(wq->sq.qid));
+       CQE_WRID_SQ_IDX(&cqe) = swcqe->idx;
+       cqe.bits_type_ts = cpu_to_be64(CQE_GENBIT_V((u64)cq->gen));
+       cq->sw_queue[cq->sw_pidx] = cqe;
+       t4_swcq_produce(cq);
+}
+
+static void advance_oldest_read(struct t4_wq *wq);
+
+int c4iw_flush_sq(struct c4iw_qp *qhp)
+{
+       int flushed = 0;
+       struct t4_wq *wq = &qhp->wq;
+       struct c4iw_cq *chp = to_c4iw_cq(qhp->ibqp.send_cq);
+       struct t4_cq *cq = &chp->cq;
+       int idx;
+       struct t4_swsqe *swsqe;
+
+       if (wq->sq.flush_cidx == -1)
+               wq->sq.flush_cidx = wq->sq.cidx;
+       idx = wq->sq.flush_cidx;
+       BUG_ON(idx >= wq->sq.size);
+       while (idx != wq->sq.pidx) {
+               swsqe = &wq->sq.sw_sq[idx];
+               BUG_ON(swsqe->flushed);
+               swsqe->flushed = 1;
+               insert_sq_cqe(wq, cq, swsqe);
+               if (wq->sq.oldest_read == swsqe) {
+                       BUG_ON(swsqe->opcode != FW_RI_READ_REQ);
+                       advance_oldest_read(wq);
+               }
+               flushed++;
+               if (++idx == wq->sq.size)
+                       idx = 0;
+       }
+       wq->sq.flush_cidx += flushed;
+       if (wq->sq.flush_cidx >= wq->sq.size)
+               wq->sq.flush_cidx -= wq->sq.size;
+       return flushed;
+}
+
+static void flush_completed_wrs(struct t4_wq *wq, struct t4_cq *cq)
+{
+       struct t4_swsqe *swsqe;
+       int cidx;
+
+       if (wq->sq.flush_cidx == -1)
+               wq->sq.flush_cidx = wq->sq.cidx;
+       cidx = wq->sq.flush_cidx;
+       BUG_ON(cidx > wq->sq.size);
+
+       while (cidx != wq->sq.pidx) {
+               swsqe = &wq->sq.sw_sq[cidx];
+               if (!swsqe->signaled) {
+                       if (++cidx == wq->sq.size)
+                               cidx = 0;
+               } else if (swsqe->complete) {
+
+                       BUG_ON(swsqe->flushed);
+
+                       /*
+                        * Insert this completed cqe into the swcq.
+                        */
+                       PDBG("%s moving cqe into swcq sq idx %u cq idx %u\n",
+                                       __func__, cidx, cq->sw_pidx);
+                       swsqe->cqe.header |= htonl(CQE_SWCQE_V(1));
+                       cq->sw_queue[cq->sw_pidx] = swsqe->cqe;
+                       t4_swcq_produce(cq);
+                       swsqe->flushed = 1;
+                       if (++cidx == wq->sq.size)
+                               cidx = 0;
+                       wq->sq.flush_cidx = cidx;
+               } else
+                       break;
+       }
+}
+
+static void create_read_req_cqe(struct t4_wq *wq, struct t4_cqe *hw_cqe,
+               struct t4_cqe *read_cqe)
+{
+       read_cqe->u.scqe.cidx = wq->sq.oldest_read->idx;
+       read_cqe->len = htonl(wq->sq.oldest_read->read_len);
+       read_cqe->header = htonl(CQE_QPID_V(CQE_QPID(hw_cqe)) |
+                       CQE_SWCQE_V(SW_CQE(hw_cqe)) |
+                       CQE_OPCODE_V(FW_RI_READ_REQ) |
+                       CQE_TYPE_V(1));
+       read_cqe->bits_type_ts = hw_cqe->bits_type_ts;
+}
+
+static void advance_oldest_read(struct t4_wq *wq)
+{
+
+       u32 rptr = wq->sq.oldest_read - wq->sq.sw_sq + 1;
+
+       if (rptr == wq->sq.size)
+               rptr = 0;
+       while (rptr != wq->sq.pidx) {
+               wq->sq.oldest_read = &wq->sq.sw_sq[rptr];
+
+               if (wq->sq.oldest_read->opcode == FW_RI_READ_REQ)
+                       return;
+               if (++rptr == wq->sq.size)
+                       rptr = 0;
+       }
+       wq->sq.oldest_read = NULL;
+}
+
+/*
+ * Move all CQEs from the HWCQ into the SWCQ.
+ * Deal with out-of-order and/or completions that complete
+ * prior unsignalled WRs.
+ */
+void c4iw_flush_hw_cq(struct c4iw_cq *chp)
+{
+       struct t4_cqe *hw_cqe, *swcqe, read_cqe;
+       struct c4iw_qp *qhp;
+       struct t4_swsqe *swsqe;
+       int ret;
+
+       PDBG("%s  cqid 0x%x\n", __func__, chp->cq.cqid);
+       ret = t4_next_hw_cqe(&chp->cq, &hw_cqe);
+
+       /*
+        * This logic is similar to poll_cq(), but not quite the same
+        * unfortunately.  Need to move pertinent HW CQEs to the SW CQ but
+        * also do any translation magic that poll_cq() normally does.
+        */
+       while (!ret) {
+               qhp = get_qhp(chp->rhp, CQE_QPID(hw_cqe));
+
+               /*
+                * drop CQEs with no associated QP
+                */
+               if (qhp == NULL)
+                       goto next_cqe;
+
+               if (CQE_OPCODE(hw_cqe) == FW_RI_TERMINATE)
+                       goto next_cqe;
+
+               if (CQE_OPCODE(hw_cqe) == FW_RI_READ_RESP) {
+
+                       /* If we have reached here because of async
+                        * event or other error, and have egress error
+                        * then drop
+                        */
+                       if (CQE_TYPE(hw_cqe) == 1)
+                               goto next_cqe;
+
+                       /* drop peer2peer RTR reads.
+                        */
+                       if (CQE_WRID_STAG(hw_cqe) == 1)
+                               goto next_cqe;
+
+                       /*
+                        * Eat completions for unsignaled read WRs.
+                        */
+                       if (!qhp->wq.sq.oldest_read->signaled) {
+                               advance_oldest_read(&qhp->wq);
+                               goto next_cqe;
+                       }
+
+                       /*
+                        * Don't write to the HWCQ, create a new read req CQE
+                        * in local memory and move it into the swcq.
+                        */
+                       create_read_req_cqe(&qhp->wq, hw_cqe, &read_cqe);
+                       hw_cqe = &read_cqe;
+                       advance_oldest_read(&qhp->wq);
+               }
+
+               /* if its a SQ completion, then do the magic to move all the
+                * unsignaled and now in-order completions into the swcq.
+                */
+               if (SQ_TYPE(hw_cqe)) {
+                       swsqe = &qhp->wq.sq.sw_sq[CQE_WRID_SQ_IDX(hw_cqe)];
+                       swsqe->cqe = *hw_cqe;
+                       swsqe->complete = 1;
+                       flush_completed_wrs(&qhp->wq, &chp->cq);
+               } else {
+                       swcqe = &chp->cq.sw_queue[chp->cq.sw_pidx];
+                       *swcqe = *hw_cqe;
+                       swcqe->header |= cpu_to_be32(CQE_SWCQE_V(1));
+                       t4_swcq_produce(&chp->cq);
+               }
+next_cqe:
+               t4_hwcq_consume(&chp->cq);
+               ret = t4_next_hw_cqe(&chp->cq, &hw_cqe);
+       }
+}
+
+static int cqe_completes_wr(struct t4_cqe *cqe, struct t4_wq *wq)
+{
+       if (CQE_OPCODE(cqe) == FW_RI_TERMINATE)
+               return 0;
+
+       if ((CQE_OPCODE(cqe) == FW_RI_RDMA_WRITE) && RQ_TYPE(cqe))
+               return 0;
+
+       if ((CQE_OPCODE(cqe) == FW_RI_READ_RESP) && SQ_TYPE(cqe))
+               return 0;
+
+       if (CQE_SEND_OPCODE(cqe) && RQ_TYPE(cqe) && t4_rq_empty(wq))
+               return 0;
+       return 1;
+}
+
+void c4iw_count_rcqes(struct t4_cq *cq, struct t4_wq *wq, int *count)
+{
+       struct t4_cqe *cqe;
+       u32 ptr;
+
+       *count = 0;
+       PDBG("%s count zero %d\n", __func__, *count);
+       ptr = cq->sw_cidx;
+       while (ptr != cq->sw_pidx) {
+               cqe = &cq->sw_queue[ptr];
+               if (RQ_TYPE(cqe) && (CQE_OPCODE(cqe) != FW_RI_READ_RESP) &&
+                   (CQE_QPID(cqe) == wq->sq.qid) && cqe_completes_wr(cqe, wq))
+                       (*count)++;
+               if (++ptr == cq->size)
+                       ptr = 0;
+       }
+       PDBG("%s cq %p count %d\n", __func__, cq, *count);
+}
+
+/*
+ * poll_cq
+ *
+ * Caller must:
+ *     check the validity of the first CQE,
+ *     supply the wq assicated with the qpid.
+ *
+ * credit: cq credit to return to sge.
+ * cqe_flushed: 1 iff the CQE is flushed.
+ * cqe: copy of the polled CQE.
+ *
+ * return value:
+ *    0                    CQE returned ok.
+ *    -EAGAIN       CQE skipped, try again.
+ *    -EOVERFLOW    CQ overflow detected.
+ */
+static int poll_cq(struct t4_wq *wq, struct t4_cq *cq, struct t4_cqe *cqe,
+                  u8 *cqe_flushed, u64 *cookie, u32 *credit)
+{
+       int ret = 0;
+       struct t4_cqe *hw_cqe, read_cqe;
+
+       *cqe_flushed = 0;
+       *credit = 0;
+       ret = t4_next_cqe(cq, &hw_cqe);
+       if (ret)
+               return ret;
+
+       PDBG("%s CQE OVF %u qpid 0x%0x genbit %u type %u status 0x%0x"
+            " opcode 0x%0x len 0x%0x wrid_hi_stag 0x%x wrid_low_msn 0x%x\n",
+            __func__, CQE_OVFBIT(hw_cqe), CQE_QPID(hw_cqe),
+            CQE_GENBIT(hw_cqe), CQE_TYPE(hw_cqe), CQE_STATUS(hw_cqe),
+            CQE_OPCODE(hw_cqe), CQE_LEN(hw_cqe), CQE_WRID_HI(hw_cqe),
+            CQE_WRID_LOW(hw_cqe));
+
+       /*
+        * skip cqe's not affiliated with a QP.
+        */
+       if (wq == NULL) {
+               ret = -EAGAIN;
+               goto skip_cqe;
+       }
+
+       /*
+       * skip hw cqe's if the wq is flushed.
+       */
+       if (wq->flushed && !SW_CQE(hw_cqe)) {
+               ret = -EAGAIN;
+               goto skip_cqe;
+       }
+
+       /*
+        * skip TERMINATE cqes...
+        */
+       if (CQE_OPCODE(hw_cqe) == FW_RI_TERMINATE) {
+               ret = -EAGAIN;
+               goto skip_cqe;
+       }
+
+       /*
+        * Gotta tweak READ completions:
+        *      1) the cqe doesn't contain the sq_wptr from the wr.
+        *      2) opcode not reflected from the wr.
+        *      3) read_len not reflected from the wr.
+        *      4) cq_type is RQ_TYPE not SQ_TYPE.
+        */
+       if (RQ_TYPE(hw_cqe) && (CQE_OPCODE(hw_cqe) == FW_RI_READ_RESP)) {
+
+               /* If we have reached here because of async
+                * event or other error, and have egress error
+                * then drop
+                */
+               if (CQE_TYPE(hw_cqe) == 1) {
+                       if (CQE_STATUS(hw_cqe))
+                               t4_set_wq_in_error(wq);
+                       ret = -EAGAIN;
+                       goto skip_cqe;
+               }
+
+               /* If this is an unsolicited read response, then the read
+                * was generated by the kernel driver as part of peer-2-peer
+                * connection setup.  So ignore the completion.
+                */
+               if (CQE_WRID_STAG(hw_cqe) == 1) {
+                       if (CQE_STATUS(hw_cqe))
+                               t4_set_wq_in_error(wq);
+                       ret = -EAGAIN;
+                       goto skip_cqe;
+               }
+
+               /*
+                * Eat completions for unsignaled read WRs.
+                */
+               if (!wq->sq.oldest_read->signaled) {
+                       advance_oldest_read(wq);
+                       ret = -EAGAIN;
+                       goto skip_cqe;
+               }
+
+               /*
+                * Don't write to the HWCQ, so create a new read req CQE
+                * in local memory.
+                */
+               create_read_req_cqe(wq, hw_cqe, &read_cqe);
+               hw_cqe = &read_cqe;
+               advance_oldest_read(wq);
+       }
+
+       if (CQE_STATUS(hw_cqe) || t4_wq_in_error(wq)) {
+               *cqe_flushed = (CQE_STATUS(hw_cqe) == T4_ERR_SWFLUSH);
+               t4_set_wq_in_error(wq);
+       }
+
+       /*
+        * RECV completion.
+        */
+       if (RQ_TYPE(hw_cqe)) {
+
+               /*
+                * HW only validates 4 bits of MSN.  So we must validate that
+                * the MSN in the SEND is the next expected MSN.  If its not,
+                * then we complete this with T4_ERR_MSN and mark the wq in
+                * error.
+                */
+
+               if (t4_rq_empty(wq)) {
+                       t4_set_wq_in_error(wq);
+                       ret = -EAGAIN;
+                       goto skip_cqe;
+               }
+               if (unlikely((CQE_WRID_MSN(hw_cqe) != (wq->rq.msn)))) {
+                       t4_set_wq_in_error(wq);
+                       hw_cqe->header |= htonl(CQE_STATUS_V(T4_ERR_MSN));
+                       goto proc_cqe;
+               }
+               goto proc_cqe;
+       }
+
+       /*
+        * If we get here its a send completion.
+        *
+        * Handle out of order completion. These get stuffed
+        * in the SW SQ. Then the SW SQ is walked to move any
+        * now in-order completions into the SW CQ.  This handles
+        * 2 cases:
+        *      1) reaping unsignaled WRs when the first subsequent
+        *         signaled WR is completed.
+        *      2) out of order read completions.
+        */
+       if (!SW_CQE(hw_cqe) && (CQE_WRID_SQ_IDX(hw_cqe) != wq->sq.cidx)) {
+               struct t4_swsqe *swsqe;
+
+               PDBG("%s out of order completion going in sw_sq at idx %u\n",
+                    __func__, CQE_WRID_SQ_IDX(hw_cqe));
+               swsqe = &wq->sq.sw_sq[CQE_WRID_SQ_IDX(hw_cqe)];
+               swsqe->cqe = *hw_cqe;
+               swsqe->complete = 1;
+               ret = -EAGAIN;
+               goto flush_wq;
+       }
+
+proc_cqe:
+       *cqe = *hw_cqe;
+
+       /*
+        * Reap the associated WR(s) that are freed up with this
+        * completion.
+        */
+       if (SQ_TYPE(hw_cqe)) {
+               int idx = CQE_WRID_SQ_IDX(hw_cqe);
+               BUG_ON(idx >= wq->sq.size);
+
+               /*
+               * Account for any unsignaled completions completed by
+               * this signaled completion.  In this case, cidx points
+               * to the first unsignaled one, and idx points to the
+               * signaled one.  So adjust in_use based on this delta.
+               * if this is not completing any unsigned wrs, then the
+               * delta will be 0. Handle wrapping also!
+               */
+               if (idx < wq->sq.cidx)
+                       wq->sq.in_use -= wq->sq.size + idx - wq->sq.cidx;
+               else
+                       wq->sq.in_use -= idx - wq->sq.cidx;
+               BUG_ON(wq->sq.in_use <= 0 && wq->sq.in_use >= wq->sq.size);
+
+               wq->sq.cidx = (uint16_t)idx;
+               PDBG("%s completing sq idx %u\n", __func__, wq->sq.cidx);
+               *cookie = wq->sq.sw_sq[wq->sq.cidx].wr_id;
+               if (c4iw_wr_log)
+                       c4iw_log_wr_stats(wq, hw_cqe);
+               t4_sq_consume(wq);
+       } else {
+               PDBG("%s completing rq idx %u\n", __func__, wq->rq.cidx);
+               *cookie = wq->rq.sw_rq[wq->rq.cidx].wr_id;
+               BUG_ON(t4_rq_empty(wq));
+               if (c4iw_wr_log)
+                       c4iw_log_wr_stats(wq, hw_cqe);
+               t4_rq_consume(wq);
+               goto skip_cqe;
+       }
+
+flush_wq:
+       /*
+        * Flush any completed cqes that are now in-order.
+        */
+       flush_completed_wrs(wq, cq);
+
+skip_cqe:
+       if (SW_CQE(hw_cqe)) {
+               PDBG("%s cq %p cqid 0x%x skip sw cqe cidx %u\n",
+                    __func__, cq, cq->cqid, cq->sw_cidx);
+               t4_swcq_consume(cq);
+       } else {
+               PDBG("%s cq %p cqid 0x%x skip hw cqe cidx %u\n",
+                    __func__, cq, cq->cqid, cq->cidx);
+               t4_hwcq_consume(cq);
+       }
+       return ret;
+}
+
+/*
+ * Get one cq entry from c4iw and map it to openib.
+ *
+ * Returns:
+ *     0                       cqe returned
+ *     -ENODATA                EMPTY;
+ *     -EAGAIN                 caller must try again
+ *     any other -errno        fatal error
+ */
+static int c4iw_poll_cq_one(struct c4iw_cq *chp, struct ib_wc *wc)
+{
+       struct c4iw_qp *qhp = NULL;
+       struct t4_cqe uninitialized_var(cqe), *rd_cqe;
+       struct t4_wq *wq;
+       u32 credit = 0;
+       u8 cqe_flushed;
+       u64 cookie = 0;
+       int ret;
+
+       ret = t4_next_cqe(&chp->cq, &rd_cqe);
+
+       if (ret)
+               return ret;
+
+       qhp = get_qhp(chp->rhp, CQE_QPID(rd_cqe));
+       if (!qhp)
+               wq = NULL;
+       else {
+               spin_lock(&qhp->lock);
+               wq = &(qhp->wq);
+       }
+       ret = poll_cq(wq, &(chp->cq), &cqe, &cqe_flushed, &cookie, &credit);
+       if (ret)
+               goto out;
+
+       wc->wr_id = cookie;
+       wc->qp = &qhp->ibqp;
+       wc->vendor_err = CQE_STATUS(&cqe);
+       wc->wc_flags = 0;
+
+       PDBG("%s qpid 0x%x type %d opcode %d status 0x%x len %u wrid hi 0x%x "
+            "lo 0x%x cookie 0x%llx\n", __func__, CQE_QPID(&cqe),
+            CQE_TYPE(&cqe), CQE_OPCODE(&cqe), CQE_STATUS(&cqe), CQE_LEN(&cqe),
+            CQE_WRID_HI(&cqe), CQE_WRID_LOW(&cqe), (unsigned long long)cookie);
+
+       if (CQE_TYPE(&cqe) == 0) {
+               if (!CQE_STATUS(&cqe))
+                       wc->byte_len = CQE_LEN(&cqe);
+               else
+                       wc->byte_len = 0;
+               wc->opcode = IB_WC_RECV;
+               if (CQE_OPCODE(&cqe) == FW_RI_SEND_WITH_INV ||
+                   CQE_OPCODE(&cqe) == FW_RI_SEND_WITH_SE_INV) {
+                       wc->ex.invalidate_rkey = CQE_WRID_STAG(&cqe);
+                       wc->wc_flags |= IB_WC_WITH_INVALIDATE;
+               }
+       } else {
+               switch (CQE_OPCODE(&cqe)) {
+               case FW_RI_RDMA_WRITE:
+                       wc->opcode = IB_WC_RDMA_WRITE;
+                       break;
+               case FW_RI_READ_REQ:
+                       wc->opcode = IB_WC_RDMA_READ;
+                       wc->byte_len = CQE_LEN(&cqe);
+                       break;
+               case FW_RI_SEND_WITH_INV:
+               case FW_RI_SEND_WITH_SE_INV:
+                       wc->opcode = IB_WC_SEND;
+                       wc->wc_flags |= IB_WC_WITH_INVALIDATE;
+                       break;
+               case FW_RI_SEND:
+               case FW_RI_SEND_WITH_SE:
+                       wc->opcode = IB_WC_SEND;
+                       break;
+               case FW_RI_BIND_MW:
+                       wc->opcode = IB_WC_BIND_MW;
+                       break;
+
+               case FW_RI_LOCAL_INV:
+                       wc->opcode = IB_WC_LOCAL_INV;
+                       break;
+               case FW_RI_FAST_REGISTER:
+                       wc->opcode = IB_WC_FAST_REG_MR;
+                       break;
+               default:
+                       printk(KERN_ERR MOD "Unexpected opcode %d "
+                              "in the CQE received for QPID=0x%0x\n",
+                              CQE_OPCODE(&cqe), CQE_QPID(&cqe));
+                       ret = -EINVAL;
+                       goto out;
+               }
+       }
+
+       if (cqe_flushed)
+               wc->status = IB_WC_WR_FLUSH_ERR;
+       else {
+
+               switch (CQE_STATUS(&cqe)) {
+               case T4_ERR_SUCCESS:
+                       wc->status = IB_WC_SUCCESS;
+                       break;
+               case T4_ERR_STAG:
+                       wc->status = IB_WC_LOC_ACCESS_ERR;
+                       break;
+               case T4_ERR_PDID:
+                       wc->status = IB_WC_LOC_PROT_ERR;
+                       break;
+               case T4_ERR_QPID:
+               case T4_ERR_ACCESS:
+                       wc->status = IB_WC_LOC_ACCESS_ERR;
+                       break;
+               case T4_ERR_WRAP:
+                       wc->status = IB_WC_GENERAL_ERR;
+                       break;
+               case T4_ERR_BOUND:
+                       wc->status = IB_WC_LOC_LEN_ERR;
+                       break;
+               case T4_ERR_INVALIDATE_SHARED_MR:
+               case T4_ERR_INVALIDATE_MR_WITH_MW_BOUND:
+                       wc->status = IB_WC_MW_BIND_ERR;
+                       break;
+               case T4_ERR_CRC:
+               case T4_ERR_MARKER:
+               case T4_ERR_PDU_LEN_ERR:
+               case T4_ERR_OUT_OF_RQE:
+               case T4_ERR_DDP_VERSION:
+               case T4_ERR_RDMA_VERSION:
+               case T4_ERR_DDP_QUEUE_NUM:
+               case T4_ERR_MSN:
+               case T4_ERR_TBIT:
+               case T4_ERR_MO:
+               case T4_ERR_MSN_RANGE:
+               case T4_ERR_IRD_OVERFLOW:
+               case T4_ERR_OPCODE:
+               case T4_ERR_INTERNAL_ERR:
+                       wc->status = IB_WC_FATAL_ERR;
+                       break;
+               case T4_ERR_SWFLUSH:
+                       wc->status = IB_WC_WR_FLUSH_ERR;
+                       break;
+               default:
+                       printk(KERN_ERR MOD
+                              "Unexpected cqe_status 0x%x for QPID=0x%0x\n",
+                              CQE_STATUS(&cqe), CQE_QPID(&cqe));
+                       ret = -EINVAL;
+               }
+       }
+out:
+       if (wq)
+               spin_unlock(&qhp->lock);
+       return ret;
+}
+
+int c4iw_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *wc)
+{
+       struct c4iw_cq *chp;
+       unsigned long flags;
+       int npolled;
+       int err = 0;
+
+       chp = to_c4iw_cq(ibcq);
+
+       spin_lock_irqsave(&chp->lock, flags);
+       for (npolled = 0; npolled < num_entries; ++npolled) {
+               do {
+                       err = c4iw_poll_cq_one(chp, wc + npolled);
+               } while (err == -EAGAIN);
+               if (err)
+                       break;
+       }
+       spin_unlock_irqrestore(&chp->lock, flags);
+       return !err || err == -ENODATA ? npolled : err;
+}
+
+int c4iw_destroy_cq(struct ib_cq *ib_cq)
+{
+       struct c4iw_cq *chp;
+       struct c4iw_ucontext *ucontext;
+
+       PDBG("%s ib_cq %p\n", __func__, ib_cq);
+       chp = to_c4iw_cq(ib_cq);
+
+       remove_handle(chp->rhp, &chp->rhp->cqidr, chp->cq.cqid);
+       atomic_dec(&chp->refcnt);
+       wait_event(chp->wait, !atomic_read(&chp->refcnt));
+
+       ucontext = ib_cq->uobject ? to_c4iw_ucontext(ib_cq->uobject->context)
+                                 : NULL;
+       destroy_cq(&chp->rhp->rdev, &chp->cq,
+                  ucontext ? &ucontext->uctx : &chp->cq.rdev->uctx);
+       kfree(chp);
+       return 0;
+}
+
+struct ib_cq *c4iw_create_cq(struct ib_device *ibdev, int entries,
+                            int vector, struct ib_ucontext *ib_context,
+                            struct ib_udata *udata)
+{
+       struct c4iw_dev *rhp;
+       struct c4iw_cq *chp;
+       struct c4iw_create_cq_resp uresp;
+       struct c4iw_ucontext *ucontext = NULL;
+       int ret;
+       size_t memsize, hwentries;
+       struct c4iw_mm_entry *mm, *mm2;
+
+       PDBG("%s ib_dev %p entries %d\n", __func__, ibdev, entries);
+
+       rhp = to_c4iw_dev(ibdev);
+
+       if (vector >= rhp->rdev.lldi.nciq)
+               return ERR_PTR(-EINVAL);
+
+       chp = kzalloc(sizeof(*chp), GFP_KERNEL);
+       if (!chp)
+               return ERR_PTR(-ENOMEM);
+
+       if (ib_context)
+               ucontext = to_c4iw_ucontext(ib_context);
+
+       /* account for the status page. */
+       entries++;
+
+       /* IQ needs one extra entry to differentiate full vs empty. */
+       entries++;
+
+       /*
+        * entries must be multiple of 16 for HW.
+        */
+       entries = roundup(entries, 16);
+
+       /*
+        * Make actual HW queue 2x to avoid cdix_inc overflows.
+        */
+       hwentries = min(entries * 2, rhp->rdev.hw_queue.t4_max_iq_size);
+
+       /*
+        * Make HW queue at least 64 entries so GTS updates aren't too
+        * frequent.
+        */
+       if (hwentries < 64)
+               hwentries = 64;
+
+       memsize = hwentries * sizeof *chp->cq.queue;
+
+       /*
+        * memsize must be a multiple of the page size if its a user cq.
+        */
+       if (ucontext)
+               memsize = roundup(memsize, PAGE_SIZE);
+       chp->cq.size = hwentries;
+       chp->cq.memsize = memsize;
+       chp->cq.vector = vector;
+
+       ret = create_cq(&rhp->rdev, &chp->cq,
+                       ucontext ? &ucontext->uctx : &rhp->rdev.uctx);
+       if (ret)
+               goto err1;
+
+       chp->rhp = rhp;
+       chp->cq.size--;                         /* status page */
+       chp->ibcq.cqe = entries - 2;
+       spin_lock_init(&chp->lock);
+       spin_lock_init(&chp->comp_handler_lock);
+       atomic_set(&chp->refcnt, 1);
+       init_waitqueue_head(&chp->wait);
+       ret = insert_handle(rhp, &rhp->cqidr, chp, chp->cq.cqid);
+       if (ret)
+               goto err2;
+
+       if (ucontext) {
+               mm = kmalloc(sizeof *mm, GFP_KERNEL);
+               if (!mm)
+                       goto err3;
+               mm2 = kmalloc(sizeof *mm2, GFP_KERNEL);
+               if (!mm2)
+                       goto err4;
+
+               uresp.qid_mask = rhp->rdev.cqmask;
+               uresp.cqid = chp->cq.cqid;
+               uresp.size = chp->cq.size;
+               uresp.memsize = chp->cq.memsize;
+               spin_lock(&ucontext->mmap_lock);
+               uresp.key = ucontext->key;
+               ucontext->key += PAGE_SIZE;
+               uresp.gts_key = ucontext->key;
+               ucontext->key += PAGE_SIZE;
+               spin_unlock(&ucontext->mmap_lock);
+               ret = ib_copy_to_udata(udata, &uresp,
+                                      sizeof(uresp) - sizeof(uresp.reserved));
+               if (ret)
+                       goto err5;
+
+               mm->key = uresp.key;
+               mm->addr = virt_to_phys(chp->cq.queue);
+               mm->len = chp->cq.memsize;
+               insert_mmap(ucontext, mm);
+
+               mm2->key = uresp.gts_key;
+               mm2->addr = chp->cq.ugts;
+               mm2->len = PAGE_SIZE;
+               insert_mmap(ucontext, mm2);
+       }
+       PDBG("%s cqid 0x%0x chp %p size %u memsize %zu, dma_addr 0x%0llx\n",
+            __func__, chp->cq.cqid, chp, chp->cq.size,
+            chp->cq.memsize, (unsigned long long) chp->cq.dma_addr);
+       return &chp->ibcq;
+err5:
+       kfree(mm2);
+err4:
+       kfree(mm);
+err3:
+       remove_handle(rhp, &rhp->cqidr, chp->cq.cqid);
+err2:
+       destroy_cq(&chp->rhp->rdev, &chp->cq,
+                  ucontext ? &ucontext->uctx : &rhp->rdev.uctx);
+err1:
+       kfree(chp);
+       return ERR_PTR(ret);
+}
+
+int c4iw_resize_cq(struct ib_cq *cq, int cqe, struct ib_udata *udata)
+{
+       return -ENOSYS;
+}
+
+int c4iw_arm_cq(struct ib_cq *ibcq, enum ib_cq_notify_flags flags)
+{
+       struct c4iw_cq *chp;
+       int ret;
+       unsigned long flag;
+
+       chp = to_c4iw_cq(ibcq);
+       spin_lock_irqsave(&chp->lock, flag);
+       ret = t4_arm_cq(&chp->cq,
+                       (flags & IB_CQ_SOLICITED_MASK) == IB_CQ_SOLICITED);
+       spin_unlock_irqrestore(&chp->lock, flag);
+       if (ret && !(flags & IB_CQ_REPORT_MISSED_EVENTS))
+               ret = 0;
+       return ret;
+}