[openib-general] [PATCH] RFC libibverbs - Pass provider data through ibv_cmd_req_notify_cq()

[Steve Wise]

Roland,

Here is another change I need to support kernel bypass in the driver I'm
working on.  For this device, the req_notify_cq() operation cannot be
bypassed.  Further, the lib needs to pass some info down to the kernel
verb to correctly implement re-arm.  

This patch enables passing provider-specific data down to the kernel
verb.  A kernel patch is also needed, that I will submit as a separate
RFC patch.  There are no dependencies build-wise between the user and
kernel patches by the way.  You just will need both patches to get
provider data passed down to your kernel verb.

Comments?


Steve.

-------------------------

Pass provider-specific data down in ibv_cmd_req_notify_cq().

From: Steve Wise <swise at opengridcomputing.com>

The Chelsio iwarp provider library needs to pass information to the
kernel verb for re-arming the CQ.

Signed-off-by: Steve Wise <swise at opengridcomputing.com>
---

 libibverbs/include/infiniband/driver.h |    5 ++++-
 libibverbs/src/cmd.c                   |   12 ++++++------
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/libibverbs/include/infiniband/driver.h b/libibverbs/include/infiniband/driver.h
index 45bd1b0..279485b 100644
--- a/libibverbs/include/infiniband/driver.h
+++ b/libibverbs/include/infiniband/driver.h
@@ -95,7 +95,10 @@ int ibv_cmd_create_cq(struct ibv_context
 		      struct ibv_create_cq *cmd, size_t cmd_size,
 		      struct ibv_create_cq_resp *resp, size_t resp_size);
 int ibv_cmd_poll_cq(struct ibv_cq *cq, int ne, struct ibv_wc *wc);
-int ibv_cmd_req_notify_cq(struct ibv_cq *cq, int solicited_only);
+#define IBV_CMD_REQ_NOTIFY_HAS_CMD_DATA
+int ibv_cmd_req_notify_cq(struct ibv_cq *cq, int solicited_only,
+			  struct ibv_req_notify_cq *cmd, size_t cmd_size);
+
 #define IBV_CMD_RESIZE_CQ_HAS_RESP_PARAMS
 int ibv_cmd_resize_cq(struct ibv_cq *cq, int cqe,
 		      struct ibv_resize_cq *cmd, size_t cmd_size,
diff --git a/libibverbs/src/cmd.c b/libibverbs/src/cmd.c
index 8dbdfe8..15eccdc 100644
--- a/libibverbs/src/cmd.c
+++ b/libibverbs/src/cmd.c
@@ -372,15 +372,15 @@ out:
 	return ret;
 }
 
-int ibv_cmd_req_notify_cq(struct ibv_cq *ibcq, int solicited_only)
+int ibv_cmd_req_notify_cq(struct ibv_cq *ibcq, int solicited_only,
+			  struct ibv_req_notify_cq *cmd, size_t cmd_size)
 {
-	struct ibv_req_notify_cq cmd;
 
-	IBV_INIT_CMD(&cmd, sizeof cmd, REQ_NOTIFY_CQ);
-	cmd.cq_handle = ibcq->handle;
-	cmd.solicited = !!solicited_only;
+	IBV_INIT_CMD(cmd, cmd_size, REQ_NOTIFY_CQ);
+	cmd->cq_handle = ibcq->handle;
+	cmd->solicited = !!solicited_only;
 
-	if (write(ibcq->context->cmd_fd, &cmd, sizeof cmd) != sizeof cmd)
+	if (write(ibcq->context->cmd_fd, cmd, cmd_size) != cmd_size)
 		return errno;
 
 	return 0;