IB: Add CQ comp_vector support

Add a num_comp_vectors member to struct ib_device and extend
ib_create_cq() to pass in a comp_vector parameter -- this parallels
the userspace libibverbs API.  Update all hardware drivers to set
num_comp_vectors to 1 and have all ULPs pass 0 for the comp_vector
value.  Pass the value of num_comp_vectors to userspace rather than
hard-coding a value of 1.

We want multiple CQ event vector support (via MSI-X or similar for
adapters that can generate multiple interrupts), but it's not clear
how many vectors we want, or how we want to deal with policy issues
such as how to decide which vector to use or how to set up interrupt
affinity.  This patch is useful for experimenting, since no core
changes will be necessary when updating a driver to support multiple
vectors, and we know that we want to make at least these changes
anyway.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

4 files changed, 5 insertions, 4 deletions

diff --git a/drivers/infiniband/core/mad.c b/drivers/infiniband/core/mad.c
index 6edfecf1be72..85ccf13b8041 100644
--- a/drivers/infiniband/core/mad.c
+++ b/drivers/infiniband/core/mad.c
@@ -2771,7 +2771,7 @@ static int ib_mad_port_open(struct ib_device *device,
 	cq_size = (IB_MAD_QP_SEND_SIZE + IB_MAD_QP_RECV_SIZE) * 2;
 	port_priv->cq = ib_create_cq(port_priv->device,
 				     ib_mad_thread_completion_handler,
-				     NULL, port_priv, cq_size);
+				     NULL, port_priv, cq_size, 0);
 	if (IS_ERR(port_priv->cq)) {
 		printk(KERN_ERR PFX "Couldn't create ib_mad CQ\n");
 		ret = PTR_ERR(port_priv->cq);
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 4fd75afa6a3a..bab66769be14 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -802,6 +802,7 @@ ssize_t ib_uverbs_create_cq(struct ib_uverbs_file *file,
 	INIT_LIST_HEAD(&obj->async_list);
 
 	cq = file->device->ib_dev->create_cq(file->device->ib_dev, cmd.cqe,
+					     cmd.comp_vector,
 					     file->ucontext, &udata);
 	if (IS_ERR(cq)) {
 		ret = PTR_ERR(cq);
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index f8bc822a3cc3..d44e54799651 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -752,7 +752,7 @@ static void ib_uverbs_add_one(struct ib_device *device)
 	spin_unlock(&map_lock);
 
 	uverbs_dev->ib_dev           = device;
-	uverbs_dev->num_comp_vectors = 1;
+	uverbs_dev->num_comp_vectors = device->num_comp_vectors;
 
 	uverbs_dev->dev = cdev_alloc();
 	if (!uverbs_dev->dev)
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index ccdf93d30b01..86ed8af9c7e6 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -609,11 +609,11 @@ EXPORT_SYMBOL(ib_destroy_qp);
 struct ib_cq *ib_create_cq(struct ib_device *device,
 			   ib_comp_handler comp_handler,
 			   void (*event_handler)(struct ib_event *, void *),
-			   void *cq_context, int cqe)
+			   void *cq_context, int cqe, int comp_vector)
 {
 	struct ib_cq *cq;
 
-	cq = device->create_cq(device, cqe, NULL, NULL);
+	cq = device->create_cq(device, cqe, comp_vector, NULL, NULL);
 
 	if (!IS_ERR(cq)) {
 		cq->device        = device;