IB/mthca: Add device-specific support for resizing CQs

Add low-level driver support for resizing CQs (both kernel and
userspace) to mthca.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 123 insertions, 4 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_provider.c b/drivers/infiniband/hw/mthca/mthca_provider.c
index e88e39aef85a..cd2038bdd1ac 100644
--- a/drivers/infiniband/hw/mthca/mthca_provider.c
+++ b/drivers/infiniband/hw/mthca/mthca_provider.c
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
  * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
- * Copyright (c) 2005 Cisco Systems. All rights reserved.
+ * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
  * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
  * Copyright (c) 2004 Voltaire, Inc. All rights reserved.
  *
@@ -669,9 +669,9 @@ static struct ib_cq *mthca_create_cq(struct ib_device *ibdev, int entries,
         }
 
         if (context) {
-                cq->mr.ibmr.lkey    = ucmd.lkey;
-                cq->set_ci_db_index = ucmd.set_db_index;
-                cq->arm_db_index    = ucmd.arm_db_index;
+                cq->buf.mr.ibmr.lkey = ucmd.lkey;
+                cq->set_ci_db_index  = ucmd.set_db_index;
+                cq->arm_db_index     = ucmd.arm_db_index;
         }
 
         for (nent = 1; nent <= entries; nent <<= 1)
@@ -689,6 +689,8 @@ static struct ib_cq *mthca_create_cq(struct ib_device *ibdev, int entries,
                 goto err_free;
         }
 
+        cq->resize_buf = NULL;
+
         return &cq->ibcq;
 
 err_free:
@@ -707,6 +709,121 @@ err_unmap_set:
         return ERR_PTR(err);
 }
 
+static int mthca_alloc_resize_buf(struct mthca_dev *dev, struct mthca_cq *cq,
+                                  int entries)
+{
+        int ret;
+
+        spin_lock_irq(&cq->lock);
+        if (cq->resize_buf) {
+                ret = -EBUSY;
+                goto unlock;
+        }
+
+        cq->resize_buf = kmalloc(sizeof *cq->resize_buf, GFP_ATOMIC);
+        if (!cq->resize_buf) {
+                ret = -ENOMEM;
+                goto unlock;
+        }
+
+        cq->resize_buf->state = CQ_RESIZE_ALLOC;
+
+        ret = 0;
+
+unlock:
+        spin_unlock_irq(&cq->lock);
+
+        if (ret)
+                return ret;
+
+        ret = mthca_alloc_cq_buf(dev, &cq->resize_buf->buf, entries);
+        if (ret) {
+                spin_lock_irq(&cq->lock);
+                kfree(cq->resize_buf);
+                cq->resize_buf = NULL;
+                spin_unlock_irq(&cq->lock);
+                return ret;
+        }
+
+        cq->resize_buf->cqe = entries - 1;
+
+        spin_lock_irq(&cq->lock);
+        cq->resize_buf->state = CQ_RESIZE_READY;
+        spin_unlock_irq(&cq->lock);
+
+        return 0;
+}
+
+static int mthca_resize_cq(struct ib_cq *ibcq, int entries, struct ib_udata *udata)
+{
+        struct mthca_dev *dev = to_mdev(ibcq->device);
+        struct mthca_cq *cq = to_mcq(ibcq);
+        struct mthca_resize_cq ucmd;
+        u32 lkey;
+        u8 status;
+        int ret;
+
+        if (entries < 1 || entries > dev->limits.max_cqes)
+                return -EINVAL;
+
+        entries = roundup_pow_of_two(entries + 1);
+        if (entries == ibcq->cqe + 1)
+                return 0;
+
+        if (cq->is_kernel) {
+                ret = mthca_alloc_resize_buf(dev, cq, entries);
+                if (ret)
+                        return ret;
+                lkey = cq->resize_buf->buf.mr.ibmr.lkey;
+        } else {
+                if (ib_copy_from_udata(&ucmd, udata, sizeof ucmd))
+                        return -EFAULT;
+                lkey = ucmd.lkey;
+        }
+
+        ret = mthca_RESIZE_CQ(dev, cq->cqn, lkey, long_log2(entries), &status);
+        if (status)
+                ret = -EINVAL;
+
+        if (ret) {
+                if (cq->resize_buf) {
+                        mthca_free_cq_buf(dev, &cq->resize_buf->buf,
+                                          cq->resize_buf->cqe);
+                        kfree(cq->resize_buf);
+                        spin_lock_irq(&cq->lock);
+                        cq->resize_buf = NULL;
+                        spin_unlock_irq(&cq->lock);
+                }
+                return ret;
+        }
+
+        if (cq->is_kernel) {
+                struct mthca_cq_buf tbuf;
+                int tcqe;
+
+                spin_lock_irq(&cq->lock);
+                if (cq->resize_buf->state == CQ_RESIZE_READY) {
+                        mthca_cq_resize_copy_cqes(cq);
+                        tbuf         = cq->buf;
+                        tcqe         = cq->ibcq.cqe;
+                        cq->buf      = cq->resize_buf->buf;
+                        cq->ibcq.cqe = cq->resize_buf->cqe;
+                } else {
+                        tbuf = cq->resize_buf->buf;
+                        tcqe = cq->resize_buf->cqe;
+                }
+
+                kfree(cq->resize_buf);
+                cq->resize_buf = NULL;
+                spin_unlock_irq(&cq->lock);
+
+                mthca_free_cq_buf(dev, &tbuf, tcqe);
+        } else
+                ibcq->cqe = entries - 1;
+
+        return 0;
+}
+
 static int mthca_destroy_cq(struct ib_cq *cq)
 {
         if (cq->uobject) {
@@ -1113,6 +1230,7 @@ int mthca_register_device(struct mthca_dev *dev)
                 (1ull << IB_USER_VERBS_CMD_DEREG_MR)            |
                 (1ull << IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL) |
                 (1ull << IB_USER_VERBS_CMD_CREATE_CQ)           |
+                (1ull << IB_USER_VERBS_CMD_RESIZE_CQ)           |
                 (1ull << IB_USER_VERBS_CMD_DESTROY_CQ)          |
                 (1ull << IB_USER_VERBS_CMD_CREATE_QP)           |
                 (1ull << IB_USER_VERBS_CMD_MODIFY_QP)           |
@@ -1154,6 +1272,7 @@ int mthca_register_device(struct mthca_dev *dev)
         dev->ib_dev.modify_qp            = mthca_modify_qp;
         dev->ib_dev.destroy_qp           = mthca_destroy_qp;
         dev->ib_dev.create_cq            = mthca_create_cq;
+        dev->ib_dev.resize_cq            = mthca_resize_cq;
         dev->ib_dev.destroy_cq           = mthca_destroy_cq;
         dev->ib_dev.poll_cq              = mthca_poll_cq;
         dev->ib_dev.get_dma_mr           = mthca_get_dma_mr;