[PATCH] IB uverbs: add mthca user QP support

Add support for userspace queue pairs (QPs) to mthca.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 212 insertions, 85 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_dev.h b/drivers/infiniband/hw/mthca/mthca_dev.h
index 751f69479a78..5ecdd2eeeb0f 100644
--- a/drivers/infiniband/hw/mthca/mthca_dev.h
+++ b/drivers/infiniband/hw/mthca/mthca_dev.h
@@ -440,12 +440,14 @@ int mthca_alloc_qp(struct mthca_dev *dev,
                    struct mthca_cq *recv_cq,
                    enum ib_qp_type type,
                    enum ib_sig_type send_policy,
+                   struct ib_qp_cap *cap,
                    struct mthca_qp *qp);
 int mthca_alloc_sqp(struct mthca_dev *dev,
                     struct mthca_pd *pd,
                     struct mthca_cq *send_cq,
                     struct mthca_cq *recv_cq,
                     enum ib_sig_type send_policy,
+                    struct ib_qp_cap *cap,
                     int qpn,
                     int port,
                     struct mthca_sqp *sqp);
diff --git a/drivers/infiniband/hw/mthca/mthca_provider.c b/drivers/infiniband/hw/mthca/mthca_provider.c
index 9feb7618ba41..7a58ce90e179 100644
--- a/drivers/infiniband/hw/mthca/mthca_provider.c
+++ b/drivers/infiniband/hw/mthca/mthca_provider.c
@@ -424,6 +424,7 @@ static struct ib_qp *mthca_create_qp(struct ib_pd *pd,
                                      struct ib_qp_init_attr *init_attr,
                                      struct ib_udata *udata)
 {
+        struct mthca_create_qp ucmd;
         struct mthca_qp *qp;
         int err;
 
@@ -432,41 +433,82 @@ static struct ib_qp *mthca_create_qp(struct ib_pd *pd,
         case IB_QPT_UC:
         case IB_QPT_UD:
         {
+                struct mthca_ucontext *context;
+
                 qp = kmalloc(sizeof *qp, GFP_KERNEL);
                 if (!qp)
                         return ERR_PTR(-ENOMEM);
 
-                qp->sq.max    = init_attr->cap.max_send_wr;
-                qp->rq.max    = init_attr->cap.max_recv_wr;
-                qp->sq.max_gs = init_attr->cap.max_send_sge;
-                qp->rq.max_gs = init_attr->cap.max_recv_sge;
+                if (pd->uobject) {
+                        context = to_mucontext(pd->uobject->context);
+
+                        if (ib_copy_from_udata(&ucmd, udata, sizeof ucmd))
+                                return ERR_PTR(-EFAULT);
+
+                        err = mthca_map_user_db(to_mdev(pd->device), &context->uar,
+                                                context->db_tab,
+                                                ucmd.sq_db_index, ucmd.sq_db_page);
+                        if (err) {
+                                kfree(qp);
+                                return ERR_PTR(err);
+                        }
+
+                        err = mthca_map_user_db(to_mdev(pd->device), &context->uar,
+                                                context->db_tab,
+                                                ucmd.rq_db_index, ucmd.rq_db_page);
+                        if (err) {
+                                mthca_unmap_user_db(to_mdev(pd->device),
+                                                    &context->uar,
+                                                    context->db_tab,
+                                                    ucmd.sq_db_index);
+                                kfree(qp);
+                                return ERR_PTR(err);
+                        }
+
+                        qp->mr.ibmr.lkey = ucmd.lkey;
+                        qp->sq.db_index  = ucmd.sq_db_index;
+                        qp->rq.db_index  = ucmd.rq_db_index;
+                }
 
                 err = mthca_alloc_qp(to_mdev(pd->device), to_mpd(pd),
                                      to_mcq(init_attr->send_cq),
                                      to_mcq(init_attr->recv_cq),
                                      init_attr->qp_type, init_attr->sq_sig_type,
-                                     qp);
+                                     &init_attr->cap, qp);
+
+                if (err && pd->uobject) {
+                        context = to_mucontext(pd->uobject->context);
+
+                        mthca_unmap_user_db(to_mdev(pd->device),
+                                            &context->uar,
+                                            context->db_tab,
+                                            ucmd.sq_db_index);
+                        mthca_unmap_user_db(to_mdev(pd->device),
+                                            &context->uar,
+                                            context->db_tab,
+                                            ucmd.rq_db_index);
+                }
+
                 qp->ibqp.qp_num = qp->qpn;
                 break;
         }
         case IB_QPT_SMI:
         case IB_QPT_GSI:
         {
+                /* Don't allow userspace to create special QPs */
+                if (pd->uobject)
+                        return ERR_PTR(-EINVAL);
+
                 qp = kmalloc(sizeof (struct mthca_sqp), GFP_KERNEL);
                 if (!qp)
                         return ERR_PTR(-ENOMEM);
 
-                qp->sq.max    = init_attr->cap.max_send_wr;
-                qp->rq.max    = init_attr->cap.max_recv_wr;
-                qp->sq.max_gs = init_attr->cap.max_send_sge;
-                qp->rq.max_gs = init_attr->cap.max_recv_sge;
-
                 qp->ibqp.qp_num = init_attr->qp_type == IB_QPT_SMI ? 0 : 1;
 
                 err = mthca_alloc_sqp(to_mdev(pd->device), to_mpd(pd),
                                       to_mcq(init_attr->send_cq),
                                       to_mcq(init_attr->recv_cq),
-                                      init_attr->sq_sig_type,
+                                      init_attr->sq_sig_type, &init_attr->cap,
                                       qp->ibqp.qp_num, init_attr->port_num,
                                       to_msqp(qp));
                 break;
@@ -481,13 +523,27 @@ static struct ib_qp *mthca_create_qp(struct ib_pd *pd,
                 return ERR_PTR(err);
         }
 
-        init_attr->cap.max_inline_data = 0;
+        init_attr->cap.max_inline_data = 0;
+        init_attr->cap.max_send_wr     = qp->sq.max;
+        init_attr->cap.max_recv_wr     = qp->rq.max;
+        init_attr->cap.max_send_sge    = qp->sq.max_gs;
+        init_attr->cap.max_recv_sge    = qp->rq.max_gs;
 
         return &qp->ibqp;
 }
 
 static int mthca_destroy_qp(struct ib_qp *qp)
 {
+        if (qp->uobject) {
+                mthca_unmap_user_db(to_mdev(qp->device),
+                                    &to_mucontext(qp->uobject->context)->uar,
+                                    to_mucontext(qp->uobject->context)->db_tab,
+                                    to_mqp(qp)->sq.db_index);
+                mthca_unmap_user_db(to_mdev(qp->device),
+                                    &to_mucontext(qp->uobject->context)->uar,
+                                    to_mucontext(qp->uobject->context)->db_tab,
+                                    to_mqp(qp)->rq.db_index);
+        }
         mthca_free_qp(to_mdev(qp->device), to_mqp(qp));
         kfree(qp);
         return 0;
diff --git a/drivers/infiniband/hw/mthca/mthca_qp.c b/drivers/infiniband/hw/mthca/mthca_qp.c
index 163a8ef4186f..f7126b14d5ae 100644
--- a/drivers/infiniband/hw/mthca/mthca_qp.c
+++ b/drivers/infiniband/hw/mthca/mthca_qp.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2004 Topspin Communications.  All rights reserved.
+ * Copyright (c) 2005 Cisco Systems. 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
@@ -46,7 +47,9 @@ enum {
         MTHCA_MAX_DIRECT_QP_SIZE = 4 * PAGE_SIZE,
         MTHCA_ACK_REQ_FREQ       = 10,
         MTHCA_FLIGHT_LIMIT       = 9,
-        MTHCA_UD_HEADER_SIZE     = 72 /* largest UD header possible */
+        MTHCA_UD_HEADER_SIZE     = 72, /* largest UD header possible */
+        MTHCA_INLINE_HEADER_SIZE = 4,  /* data segment overhead for inline */
+        MTHCA_INLINE_CHUNK_SIZE  = 16  /* inline data segment chunk */
 };
 
 enum {
@@ -689,7 +692,11 @@ int mthca_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, int attr_mask)
 
         /* leave arbel_sched_queue as 0 */
 
-        qp_context->usr_page   = cpu_to_be32(dev->driver_uar.index);
+        if (qp->ibqp.uobject)
+                qp_context->usr_page =
+                        cpu_to_be32(to_mucontext(qp->ibqp.uobject->context)->uar.index);
+        else
+                qp_context->usr_page = cpu_to_be32(dev->driver_uar.index);
         qp_context->local_qpn  = cpu_to_be32(qp->qpn);
         if (attr_mask & IB_QP_DEST_QPN) {
                 qp_context->remote_qpn = cpu_to_be32(attr->dest_qp_num);
@@ -954,6 +961,15 @@ static int mthca_alloc_wqe_buf(struct mthca_dev *dev,
 
         qp->send_wqe_offset = ALIGN(qp->rq.max << qp->rq.wqe_shift,
                                     1 << qp->sq.wqe_shift);
+
+        /*
+         * If this is a userspace QP, we don't actually have to
+         * allocate anything.  All we need is to calculate the WQE
+         * sizes and the send_wqe_offset, so we're done now.
+         */
+        if (pd->ibpd.uobject)
+                return 0;
+
         size = PAGE_ALIGN(qp->send_wqe_offset +
                           (qp->sq.max << qp->sq.wqe_shift));
 
@@ -1053,10 +1069,32 @@ static int mthca_alloc_wqe_buf(struct mthca_dev *dev,
         return err;
 }
 
-static int mthca_alloc_memfree(struct mthca_dev *dev,
+static void mthca_free_wqe_buf(struct mthca_dev *dev,
                                struct mthca_qp *qp)
 {
-        int ret = 0;
+        int i;
+        int size = PAGE_ALIGN(qp->send_wqe_offset +
+                              (qp->sq.max << qp->sq.wqe_shift));
+
+        if (qp->is_direct) {
+                dma_free_coherent(&dev->pdev->dev, size, qp->queue.direct.buf,
+                                  pci_unmap_addr(&qp->queue.direct, mapping));
+        } else {
+                for (i = 0; i < size / PAGE_SIZE; ++i) {
+                        dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
+                                          qp->queue.page_list[i].buf,
+                                          pci_unmap_addr(&qp->queue.page_list[i],
+                                                         mapping));
+                }
+        }
+
+        kfree(qp->wrid);
+}
+
+static int mthca_map_memfree(struct mthca_dev *dev,
+                             struct mthca_qp *qp)
+{
+        int ret;
 
         if (mthca_is_memfree(dev)) {
                 ret = mthca_table_get(dev, dev->qp_table.qp_table, qp->qpn);
@@ -1067,35 +1105,15 @@ static int mthca_alloc_memfree(struct mthca_dev *dev,
                 if (ret)
                         goto err_qpc;
 
-                ret = mthca_table_get(dev, dev->qp_table.rdb_table,
-                                      qp->qpn << dev->qp_table.rdb_shift);
-                if (ret)
-                        goto err_eqpc;
-
-                qp->rq.db_index = mthca_alloc_db(dev, MTHCA_DB_TYPE_RQ,
-                                                 qp->qpn, &qp->rq.db);
-                if (qp->rq.db_index < 0) {
-                        ret = -ENOMEM;
-                        goto err_rdb;
-                }
+                ret = mthca_table_get(dev, dev->qp_table.rdb_table,
+                                      qp->qpn << dev->qp_table.rdb_shift);
+                if (ret)
+                        goto err_eqpc;
 
-                qp->sq.db_index = mthca_alloc_db(dev, MTHCA_DB_TYPE_SQ,
-                                                 qp->qpn, &qp->sq.db);
-                if (qp->sq.db_index < 0) {
-                        ret = -ENOMEM;
-                        goto err_rq_db;
-                }
         }
 
         return 0;
 
-err_rq_db:
-        mthca_free_db(dev, MTHCA_DB_TYPE_RQ, qp->rq.db_index);
-
-err_rdb:
-        mthca_table_put(dev, dev->qp_table.rdb_table,
-                        qp->qpn << dev->qp_table.rdb_shift);
-
 err_eqpc:
         mthca_table_put(dev, dev->qp_table.eqp_table, qp->qpn);
 
@@ -1105,6 +1123,35 @@ err_qpc:
         return ret;
 }
 
+static void mthca_unmap_memfree(struct mthca_dev *dev,
+                                struct mthca_qp *qp)
+{
+        mthca_table_put(dev, dev->qp_table.rdb_table,
+                        qp->qpn << dev->qp_table.rdb_shift);
+        mthca_table_put(dev, dev->qp_table.eqp_table, qp->qpn);
+        mthca_table_put(dev, dev->qp_table.qp_table, qp->qpn);
+}
+
+static int mthca_alloc_memfree(struct mthca_dev *dev,
+                               struct mthca_qp *qp)
+{
+        int ret = 0;
+
+        if (mthca_is_memfree(dev)) {
+                qp->rq.db_index = mthca_alloc_db(dev, MTHCA_DB_TYPE_RQ,
+                                                 qp->qpn, &qp->rq.db);
+                if (qp->rq.db_index < 0)
+                        return ret;
+
+                qp->sq.db_index = mthca_alloc_db(dev, MTHCA_DB_TYPE_SQ,
+                                                 qp->qpn, &qp->sq.db);
+                if (qp->sq.db_index < 0)
+                        mthca_free_db(dev, MTHCA_DB_TYPE_RQ, qp->rq.db_index);
+        }
+
+        return ret;
+}
+
 static void mthca_free_memfree(struct mthca_dev *dev,
                                struct mthca_qp *qp)
 {
@@ -1112,11 +1159,6 @@ static void mthca_free_memfree(struct mthca_dev *dev,
                 mthca_free_db(dev, MTHCA_DB_TYPE_SQ, qp->sq.db_index);
                 mthca_free_db(dev, MTHCA_DB_TYPE_RQ, qp->rq.db_index);
         }
-
-        mthca_table_put(dev, dev->qp_table.rdb_table,
-                        qp->qpn << dev->qp_table.rdb_shift);
-        mthca_table_put(dev, dev->qp_table.eqp_table, qp->qpn);
-        mthca_table_put(dev, dev->qp_table.qp_table, qp->qpn);
 }
 
 static void mthca_wq_init(struct mthca_wq* wq)
@@ -1147,13 +1189,28 @@ static int mthca_alloc_qp_common(struct mthca_dev *dev,
         mthca_wq_init(&qp->sq);
         mthca_wq_init(&qp->rq);
 
-        ret = mthca_alloc_memfree(dev, qp);
+        ret = mthca_map_memfree(dev, qp);
         if (ret)
                 return ret;
 
         ret = mthca_alloc_wqe_buf(dev, pd, qp);
         if (ret) {
-                mthca_free_memfree(dev, qp);
+                mthca_unmap_memfree(dev, qp);
+                return ret;
+        }
+
+        /*
+         * If this is a userspace QP, we're done now.  The doorbells
+         * will be allocated and buffers will be initialized in
+         * userspace.
+         */
+        if (pd->ibpd.uobject)
+                return 0;
+
+        ret = mthca_alloc_memfree(dev, qp);
+        if (ret) {
+                mthca_free_wqe_buf(dev, qp);
+                mthca_unmap_memfree(dev, qp);
                 return ret;
         }
 
@@ -1186,22 +1243,39 @@ static int mthca_alloc_qp_common(struct mthca_dev *dev,
         return 0;
 }
 
-static void mthca_align_qp_size(struct mthca_dev *dev, struct mthca_qp *qp)
+static int mthca_set_qp_size(struct mthca_dev *dev, struct ib_qp_cap *cap,
+                             struct mthca_qp *qp)
 {
-        int i;
-
-        if (!mthca_is_memfree(dev))
-                return;
+        /* Sanity check QP size before proceeding */
+        if (cap->max_send_wr  > 65536 || cap->max_recv_wr  > 65536 ||
+            cap->max_send_sge > 64    || cap->max_recv_sge > 64)
+                return -EINVAL;
 
-        for (i = 0; 1 << i < qp->rq.max; ++i)
-                ; /* nothing */
+        if (mthca_is_memfree(dev)) {
+                qp->rq.max = cap->max_recv_wr ?
+                        roundup_pow_of_two(cap->max_recv_wr) : 0;
+                qp->sq.max = cap->max_send_wr ?
+                        roundup_pow_of_two(cap->max_send_wr) : 0;
+        } else {
+                qp->rq.max = cap->max_recv_wr;
+                qp->sq.max = cap->max_send_wr;
+        }
 
-        qp->rq.max = 1 << i;
+        qp->rq.max_gs = cap->max_recv_sge;
+        qp->sq.max_gs = max_t(int, cap->max_send_sge,
+                              ALIGN(cap->max_inline_data + MTHCA_INLINE_HEADER_SIZE,
+                                    MTHCA_INLINE_CHUNK_SIZE) /
+                              sizeof (struct mthca_data_seg));
 
-        for (i = 0; 1 << i < qp->sq.max; ++i)
-                ; /* nothing */
+        /*
+         * For MLX transport we need 2 extra S/G entries:
+         * one for the header and one for the checksum at the end
+         */
+        if ((qp->transport == MLX && qp->sq.max_gs + 2 > dev->limits.max_sg) ||
+            qp->sq.max_gs > dev->limits.max_sg || qp->rq.max_gs > dev->limits.max_sg)
+                return -EINVAL;
 
-        qp->sq.max = 1 << i;
+        return 0;
 }
 
 int mthca_alloc_qp(struct mthca_dev *dev,
@@ -1210,11 +1284,14 @@ int mthca_alloc_qp(struct mthca_dev *dev,
                    struct mthca_cq *recv_cq,
                    enum ib_qp_type type,
                    enum ib_sig_type send_policy,
+                   struct ib_qp_cap *cap,
                    struct mthca_qp *qp)
 {
         int err;
 
-        mthca_align_qp_size(dev, qp);
+        err = mthca_set_qp_size(dev, cap, qp);
+        if (err)
+                return err;
 
         switch (type) {
         case IB_QPT_RC: qp->transport = RC; break;
@@ -1247,14 +1324,17 @@ int mthca_alloc_sqp(struct mthca_dev *dev,
                     struct mthca_cq *send_cq,
                     struct mthca_cq *recv_cq,
                     enum ib_sig_type send_policy,
+                    struct ib_qp_cap *cap,
                     int qpn,
                     int port,
                     struct mthca_sqp *sqp)
 {
-        int err = 0;
         u32 mqpn = qpn * 2 + dev->qp_table.sqp_start + port - 1;
+        int err;
 
-        mthca_align_qp_size(dev, &sqp->qp);
+        err = mthca_set_qp_size(dev, cap, &sqp->qp);
+        if (err)
+                return err;
 
         sqp->header_buf_size = sqp->qp.sq.max * MTHCA_UD_HEADER_SIZE;
         sqp->header_buf = dma_alloc_coherent(&dev->pdev->dev, sqp->header_buf_size,
@@ -1313,8 +1393,6 @@ void mthca_free_qp(struct mthca_dev *dev,
                    struct mthca_qp *qp)
 {
         u8 status;
-        int size;
-        int i;
         struct mthca_cq *send_cq;
         struct mthca_cq *recv_cq;
 
@@ -1344,31 +1422,22 @@ void mthca_free_qp(struct mthca_dev *dev,
         if (qp->state != IB_QPS_RESET)
                 mthca_MODIFY_QP(dev, MTHCA_TRANS_ANY2RST, qp->qpn, 0, NULL, 0, &status);
 
-        mthca_cq_clean(dev, to_mcq(qp->ibqp.send_cq)->cqn, qp->qpn);
-        if (qp->ibqp.send_cq != qp->ibqp.recv_cq)
-                mthca_cq_clean(dev, to_mcq(qp->ibqp.recv_cq)->cqn, qp->qpn);
-
-        mthca_free_mr(dev, &qp->mr);
-
-        size = PAGE_ALIGN(qp->send_wqe_offset +
-                          (qp->sq.max << qp->sq.wqe_shift));
+        /*
+         * If this is a userspace QP, the buffers, MR, CQs and so on
+         * will be cleaned up in userspace, so all we have to do is
+         * unref the mem-free tables and free the QPN in our table.
+         */
+        if (!qp->ibqp.uobject) {
+                mthca_cq_clean(dev, to_mcq(qp->ibqp.send_cq)->cqn, qp->qpn);
+                if (qp->ibqp.send_cq != qp->ibqp.recv_cq)
+                        mthca_cq_clean(dev, to_mcq(qp->ibqp.recv_cq)->cqn, qp->qpn);
 
-        if (qp->is_direct) {
-                pci_free_consistent(dev->pdev, size,
-                                    qp->queue.direct.buf,
-                                    pci_unmap_addr(&qp->queue.direct, mapping));
-        } else {
-                for (i = 0; i < size / PAGE_SIZE; ++i) {
-                        pci_free_consistent(dev->pdev, PAGE_SIZE,
-                                            qp->queue.page_list[i].buf,
-                                            pci_unmap_addr(&qp->queue.page_list[i],
-                                                           mapping));
-                }
+                mthca_free_mr(dev, &qp->mr);
+                mthca_free_memfree(dev, qp);
+                mthca_free_wqe_buf(dev, qp);
         }
 
-        kfree(qp->wrid);
-
-        mthca_free_memfree(dev, qp);
+        mthca_unmap_memfree(dev, qp);
 
         if (is_sqp(dev, qp)) {
                 atomic_dec(&(to_mpd(qp->ibqp.pd)->sqp_count));