[openib-general] [PATCH 1/5] [RFC] core kernel changes for resize CQ

[Roland Dreier]

Core kernel changes to add support for the resize CQ operation for
userspace CQs.

---

--- infiniband/include/rdma/ib_user_verbs.h	(revision 5179)
+++ infiniband/include/rdma/ib_user_verbs.h	(working copy)
@@ -265,6 +265,17 @@ struct ib_uverbs_create_cq_resp {
 	__u32 cqe;
 };
 
+struct ib_uverbs_resize_cq {
+	__u64 response;
+	__u32 cq_handle;
+	__u32 cqe;
+	__u64 driver_data[0];
+};
+
+struct ib_uverbs_resize_cq_resp {
+	__u32 cqe;
+};
+
 struct ib_uverbs_poll_cq {
 	__u64 response;
 	__u32 cq_handle;
--- infiniband/include/rdma/ib_verbs.h	(revision 5179)
+++ infiniband/include/rdma/ib_verbs.h	(working copy)
@@ -880,7 +880,8 @@ struct ib_device {
 						struct ib_ucontext *context,
 						struct ib_udata *udata);
 	int                        (*destroy_cq)(struct ib_cq *cq);
-	int                        (*resize_cq)(struct ib_cq *cq, int cqe);
+	int                        (*resize_cq)(struct ib_cq *cq, int cqe,
+						struct ib_udata *udata);
 	int                        (*poll_cq)(struct ib_cq *cq, int num_entries,
 					      struct ib_wc *wc);
 	int                        (*peek_cq)(struct ib_cq *cq, int wc_cnt);
--- infiniband/core/uverbs_main.c	(revision 5179)
+++ infiniband/core/uverbs_main.c	(working copy)
@@ -91,6 +91,7 @@ static ssize_t (*uverbs_cmd_table[])(str
 	[IB_USER_VERBS_CMD_DEREG_MR]      	= ib_uverbs_dereg_mr,
 	[IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
 	[IB_USER_VERBS_CMD_CREATE_CQ]     	= ib_uverbs_create_cq,
+	[IB_USER_VERBS_CMD_RESIZE_CQ]     	= ib_uverbs_resize_cq,
 	[IB_USER_VERBS_CMD_POLL_CQ]     	= ib_uverbs_poll_cq,
 	[IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]     	= ib_uverbs_req_notify_cq,
 	[IB_USER_VERBS_CMD_DESTROY_CQ]    	= ib_uverbs_destroy_cq,
--- infiniband/core/verbs.c	(revision 5179)
+++ infiniband/core/verbs.c	(working copy)
@@ -325,7 +325,7 @@ int ib_resize_cq(struct ib_cq *cq,
                  int           cqe)
 {
 	return cq->device->resize_cq ?
-		cq->device->resize_cq(cq, cqe) : -ENOSYS;
+		cq->device->resize_cq(cq, cqe, NULL) : -ENOSYS;
 }
 EXPORT_SYMBOL(ib_resize_cq);
 
--- infiniband/core/uverbs.h	(revision 5179)
+++ infiniband/core/uverbs.h	(working copy)
@@ -185,6 +185,7 @@ IB_UVERBS_DECLARE_CMD(reg_mr);
 IB_UVERBS_DECLARE_CMD(dereg_mr);
 IB_UVERBS_DECLARE_CMD(create_comp_channel);
 IB_UVERBS_DECLARE_CMD(create_cq);
+IB_UVERBS_DECLARE_CMD(resize_cq);
 IB_UVERBS_DECLARE_CMD(poll_cq);
 IB_UVERBS_DECLARE_CMD(req_notify_cq);
 IB_UVERBS_DECLARE_CMD(destroy_cq);
--- infiniband/core/uverbs_cmd.c	(revision 5179)
+++ infiniband/core/uverbs_cmd.c	(working copy)
@@ -675,6 +675,46 @@ err:
 	return ret;
 }
 
+ssize_t ib_uverbs_resize_cq(struct ib_uverbs_file *file,
+			    const char __user *buf, int in_len,
+			    int out_len)
+{
+	struct ib_uverbs_resize_cq	cmd;
+	struct ib_uverbs_resize_cq_resp	resp;
+	struct ib_udata                 udata;
+	struct ib_cq			*cq;
+	int				ret = -EINVAL;
+
+	if (copy_from_user(&cmd, buf, sizeof cmd))
+		return -EFAULT;
+
+	INIT_UDATA(&udata, buf + sizeof cmd,
+		   (unsigned long) cmd.response + sizeof resp,
+		   in_len - sizeof cmd, out_len - sizeof resp);
+
+	down(&ib_uverbs_idr_mutex);
+
+	cq = idr_find(&ib_uverbs_cq_idr, cmd.cq_handle);
+	if (!cq || cq->uobject->context != file->ucontext || !cq->device->resize_cq)
+		goto out;
+
+	ret = cq->device->resize_cq(cq, cmd.cqe, &udata);
+	if (ret)
+		goto out;
+
+	memset(&resp, 0, sizeof resp);
+	resp.cqe = cq->cqe;
+
+	if (copy_to_user((void __user *) (unsigned long) cmd.response,
+			 &resp, sizeof resp))
+		ret = -EFAULT;
+
+out:
+	up(&ib_uverbs_idr_mutex);
+
+	return ret ? ret : in_len;
+}
+
 ssize_t ib_uverbs_poll_cq(struct ib_uverbs_file *file,
 			  const char __user *buf, int in_len,
 			  int out_len)