rdma/cxgb4: Add support for kernel mode SRQ's

This patch implements the srq specific verbs such as create/destroy/modify
and post_srq_recv. And adds srq specific structures and defines to t4.h
and uapi.

Also updates the cq poll logic to deal with completions that are
associated with the SRQ's.

This patch also handles kernel mode SRQ_LIMIT events as well as flushed
SRQ buffers

Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 48 insertions, 3 deletions

diff --git a/drivers/infiniband/hw/cxgb4/resource.c b/drivers/infiniband/hw/cxgb4/resource.c
index 0ef25ae05e6f..57ed26b3cc21 100644
--- a/drivers/infiniband/hw/cxgb4/resource.c
+++ b/drivers/infiniband/hw/cxgb4/resource.c
@@ -53,7 +53,8 @@ static int c4iw_init_qid_table(struct c4iw_rdev *rdev)
 }
 
 /* nr_* must be power of 2 */
-int c4iw_init_resource(struct c4iw_rdev *rdev, u32 nr_tpt, u32 nr_pdid)
+int c4iw_init_resource(struct c4iw_rdev *rdev, u32 nr_tpt,
+		       u32 nr_pdid, u32 nr_srqt)
 {
 	int err = 0;
 	err = c4iw_id_table_alloc(&rdev->resource.tpt_table, 0, nr_tpt, 1,
@@ -67,7 +68,17 @@ int c4iw_init_resource(struct c4iw_rdev *rdev, u32 nr_tpt, u32 nr_pdid)
 					nr_pdid, 1, 0);
 	if (err)
 		goto pdid_err;
+	if (!nr_srqt)
+		err = c4iw_id_table_alloc(&rdev->resource.srq_table, 0,
+					  1, 1, 0);
+	else
+		err = c4iw_id_table_alloc(&rdev->resource.srq_table, 0,
+					  nr_srqt, 0, 0);
+	if (err)
+		goto srq_err;
 	return 0;
+ srq_err:
+	c4iw_id_table_free(&rdev->resource.pdid_table);
  pdid_err:
 	c4iw_id_table_free(&rdev->resource.qid_table);
  qid_err:
@@ -371,13 +382,21 @@ void c4iw_rqtpool_free(struct c4iw_rdev *rdev, u32 addr, int size)
 int c4iw_rqtpool_create(struct c4iw_rdev *rdev)
 {
 	unsigned rqt_start, rqt_chunk, rqt_top;
+	int skip = 0;
 
 	rdev->rqt_pool = gen_pool_create(MIN_RQT_SHIFT, -1);
 	if (!rdev->rqt_pool)
 		return -ENOMEM;
 
-	rqt_start = rdev->lldi.vr->rq.start;
-	rqt_chunk = rdev->lldi.vr->rq.size;
+	/*
+	 * If SRQs are supported, then never use the first RQE from
+	 * the RQT region. This is because HW uses RQT index 0 as NULL.
+	 */
+	if (rdev->lldi.vr->srq.size)
+		skip = T4_RQT_ENTRY_SIZE;
+
+	rqt_start = rdev->lldi.vr->rq.start + skip;
+	rqt_chunk = rdev->lldi.vr->rq.size - skip;
 	rqt_top = rqt_start + rqt_chunk;
 
 	while (rqt_start < rqt_top) {
@@ -405,6 +424,32 @@ void c4iw_rqtpool_destroy(struct c4iw_rdev *rdev)
 	kref_put(&rdev->rqt_kref, destroy_rqtpool);
 }
 
+int c4iw_alloc_srq_idx(struct c4iw_rdev *rdev)
+{
+	int idx;
+
+	idx = c4iw_id_alloc(&rdev->resource.srq_table);
+	mutex_lock(&rdev->stats.lock);
+	if (idx == -1) {
+		rdev->stats.srqt.fail++;
+		mutex_unlock(&rdev->stats.lock);
+		return -ENOMEM;
+	}
+	rdev->stats.srqt.cur++;
+	if (rdev->stats.srqt.cur > rdev->stats.srqt.max)
+		rdev->stats.srqt.max = rdev->stats.srqt.cur;
+	mutex_unlock(&rdev->stats.lock);
+	return idx;
+}
+
+void c4iw_free_srq_idx(struct c4iw_rdev *rdev, int idx)
+{
+	c4iw_id_free(&rdev->resource.srq_table, idx);
+	mutex_lock(&rdev->stats.lock);
+	rdev->stats.srqt.cur--;
+	mutex_unlock(&rdev->stats.lock);
+}
+
 /*
  * On-Chip QP Memory.
  */