RDMA/nldev: provide detailed CQ information

Implement the RDMA nldev netlink interface for dumping detailed
CQ information.

Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/nldev.c

@@ -80,6 +80,11 @@ static const struct nla_policy nldev_policy[RDMA_NLDEV_ATTR_MAX] = {
 			.len = sizeof(struct __kernel_sockaddr_storage) },
 	[RDMA_NLDEV_ATTR_RES_DST_ADDR]	= {
 			.len = sizeof(struct __kernel_sockaddr_storage) },
+	[RDMA_NLDEV_ATTR_RES_CQ]		= { .type = NLA_NESTED },
+	[RDMA_NLDEV_ATTR_RES_CQ_ENTRY]		= { .type = NLA_NESTED },
+	[RDMA_NLDEV_ATTR_RES_CQE]		= { .type = NLA_U32 },
+	[RDMA_NLDEV_ATTR_RES_USECNT]		= { .type = NLA_U64 },
+	[RDMA_NLDEV_ATTR_RES_POLL_CTX]		= { .type = NLA_U8 },
 };
 
 static int fill_nldev_handle(struct sk_buff *msg, struct ib_device *device)
@@ -359,6 +364,39 @@ out:
 	return -EMSGSIZE;
 }
 
+static int fill_res_cq_entry(struct sk_buff *msg, struct netlink_callback *cb,
+			     struct rdma_restrack_entry *res, uint32_t port)
+{
+	struct ib_cq *cq = container_of(res, struct ib_cq, res);
+	struct nlattr *entry_attr;
+
+	entry_attr = nla_nest_start(msg, RDMA_NLDEV_ATTR_RES_CQ_ENTRY);
+	if (!entry_attr)
+		goto out;
+
+	if (nla_put_u32(msg, RDMA_NLDEV_ATTR_RES_CQE, cq->cqe))
+		goto err;
+	if (nla_put_u64_64bit(msg, RDMA_NLDEV_ATTR_RES_USECNT,
+			      atomic_read(&cq->usecnt), 0))
+		goto err;
+
+	/* Poll context is only valid for kernel CQs */
+	if (rdma_is_kernel_res(res) &&
+	    nla_put_u8(msg, RDMA_NLDEV_ATTR_RES_POLL_CTX, cq->poll_ctx))
+		goto err;
+
+	if (fill_res_name_pid(msg, res))
+		goto err;
+
+	nla_nest_end(msg, entry_attr);
+	return 0;
+
+err:
+	nla_nest_cancel(msg, entry_attr);
+out:
+	return -EMSGSIZE;
+}
+
 static int nldev_get_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
 			  struct netlink_ext_ack *extack)
 {
@@ -651,6 +689,11 @@ static const struct nldev_fill_res_entry fill_entries[RDMA_RESTRACK_MAX] = {
 		.nldev_cmd = RDMA_NLDEV_CMD_RES_CM_ID_GET,
 		.nldev_attr = RDMA_NLDEV_ATTR_RES_CM_ID,
 	},
+	[RDMA_RESTRACK_CQ] = {
+		.fill_res_func = fill_res_cq_entry,
+		.nldev_cmd = RDMA_NLDEV_CMD_RES_CQ_GET,
+		.nldev_attr = RDMA_NLDEV_ATTR_RES_CQ,
+	},
 };
 
 static int res_get_common_dumpit(struct sk_buff *skb,
@@ -799,6 +842,12 @@ static int nldev_res_get_cm_id_dumpit(struct sk_buff *skb,
 	return res_get_common_dumpit(skb, cb, RDMA_RESTRACK_CM_ID);
 }
 
+static int nldev_res_get_cq_dumpit(struct sk_buff *skb,
+				   struct netlink_callback *cb)
+{
+	return res_get_common_dumpit(skb, cb, RDMA_RESTRACK_CQ);
+}
+
 static const struct rdma_nl_cbs nldev_cb_table[RDMA_NLDEV_NUM_OPS] = {
 	[RDMA_NLDEV_CMD_GET] = {
 		.doit = nldev_get_doit,
@@ -828,6 +877,9 @@ static const struct rdma_nl_cbs nldev_cb_table[RDMA_NLDEV_NUM_OPS] = {
 	[RDMA_NLDEV_CMD_RES_CM_ID_GET] = {
 		.dump = nldev_res_get_cm_id_dumpit,
 	},
+	[RDMA_NLDEV_CMD_RES_CQ_GET] = {
+		.dump = nldev_res_get_cq_dumpit,
+	},
 };
 
 void __init nldev_init(void)

include/uapi/rdma/rdma_netlink.h

@@ -240,6 +240,8 @@ enum rdma_nldev_command {
 
 	RDMA_NLDEV_CMD_RES_CM_ID_GET, /* can dump */
 
+	RDMA_NLDEV_CMD_RES_CQ_GET, /* can dump */
+
 	RDMA_NLDEV_NUM_OPS
 };
 
@@ -364,6 +366,12 @@ enum rdma_nldev_attr {
 	RDMA_NLDEV_ATTR_RES_SRC_ADDR,		/* __kernel_sockaddr_storage */
 	RDMA_NLDEV_ATTR_RES_DST_ADDR,		/* __kernel_sockaddr_storage */
 
+	RDMA_NLDEV_ATTR_RES_CQ,			/* nested table */
+	RDMA_NLDEV_ATTR_RES_CQ_ENTRY,		/* nested table */
+	RDMA_NLDEV_ATTR_RES_CQE,		/* u32 */
+	RDMA_NLDEV_ATTR_RES_USECNT,		/* u64 */
+	RDMA_NLDEV_ATTR_RES_POLL_CTX,		/* u8 */
+
 	RDMA_NLDEV_ATTR_MAX
 };
 #endif /* _UAPI_RDMA_NETLINK_H */