verbs: Enhance async FD usage

Enhance async FD usage by adding an option to enforce it be a mandatory attribute in a given device once the applicable objects are created (e.g.QP, CQ, etc.). This is some preparation step before introducing in the next patch the ibv_import_device() verb which must use its own async FD to be able to get events on its private created objects. In addition, we moved ibv_cmd_alloc_async_fd() to be called as part of ibv_open_device() in case wasn't allocated yet (i.e. ioctl flow), this will be aligned with the import device flow that will be introduced. Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
linux-rdma · Jul 9, 2020 · 317d889 · 317d889
1 parent 5f200b1
commit 317d889
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Showing 8 changed files with 30 additions and 6 deletions.
diff --git a/libibverbs/cmd_cq.c b/libibverbs/cmd_cq.c
@@ -31,13 +31,15 @@
  */
 
 #include <infiniband/cmd_write.h>
+#include "ibverbs.h"
 
 static int ibv_icmd_create_cq(struct ibv_context *context, int cqe,
 			      struct ibv_comp_channel *channel, int comp_vector,
 			      uint32_t flags, struct ibv_cq *cq,
 			      struct ibv_command_buffer *link)
 {
 	DECLARE_FBCMD_BUFFER(cmdb, UVERBS_OBJECT_CQ, UVERBS_METHOD_CQ_CREATE, 8, link);
+	struct verbs_ex_private *priv = get_priv(context);
 	struct ib_uverbs_attr *handle;
 	struct ib_uverbs_attr *async_fd_attr;
 	uint32_t resp_cqe;
@@ -54,8 +56,11 @@ static int ibv_icmd_create_cq(struct ibv_context *context, int cqe,
 		fill_attr_in_fd(cmdb, UVERBS_ATTR_CREATE_CQ_COMP_CHANNEL, channel->fd);
 	fill_attr_in_uint32(cmdb, UVERBS_ATTR_CREATE_CQ_COMP_VECTOR, comp_vector);
 	async_fd_attr = fill_attr_in_fd(cmdb, UVERBS_ATTR_CREATE_CQ_EVENT_FD, context->async_fd);
-	/* Prevent fallback to the 'write' mode if kernel doesn't support it */
-	attr_optional(async_fd_attr);
+	if (priv->imported)
+		fallback_require_ioctl(cmdb);
+	else
+		/* Prevent fallback to the 'write' mode if kernel doesn't support it */
+		attr_optional(async_fd_attr);
 
 	if (flags) {
 		fallback_require_ex(cmdb);

diff --git a/libibverbs/cmd_device.c b/libibverbs/cmd_device.c
@@ -99,7 +99,7 @@ int ibv_cmd_query_port(struct ibv_context *context, uint8_t port_num,
 	return 0;
 }
 
-static int cmd_alloc_async_fd(struct ibv_context *context)
+int ibv_cmd_alloc_async_fd(struct ibv_context *context)
 {
 	DECLARE_COMMAND_BUFFER(cmdb, UVERBS_OBJECT_ASYNC_EVENT,
 			       UVERBS_METHOD_ASYNC_EVENT_ALLOC, 1);
@@ -153,9 +153,6 @@ static int cmd_get_context(struct verbs_context *context_ex,
 		return 0;
 	}
 	case SUCCESS:
-		ret = cmd_alloc_async_fd(context);
-		if (ret)
-			return ret;
 		break;
 	default:
 		return ret;

diff --git a/libibverbs/cmd_qp.c b/libibverbs/cmd_qp.c
@@ -76,6 +76,7 @@ static int ibv_icmd_create_qp(struct ibv_context *context,
 			      struct ibv_command_buffer *link)
 {
 	DECLARE_FBCMD_BUFFER(cmdb, UVERBS_OBJECT_QP, UVERBS_METHOD_QP_CREATE, 15, link);
+	struct verbs_ex_private *priv = get_priv(context);
 	struct ib_uverbs_attr *handle;
 	uint32_t qp_num;
 	uint32_t pd_handle;
@@ -172,6 +173,9 @@ static int ibv_icmd_create_qp(struct ibv_context *context,
 	fill_attr_in_ptr(cmdb, UVERBS_ATTR_CREATE_QP_CAP, &attr_ex->cap);
 	fill_attr_in_fd(cmdb, UVERBS_ATTR_CREATE_QP_EVENT_FD, context->async_fd);
 
+	if (priv->imported)
+		fallback_require_ioctl(cmdb);
+
 	if (attr_ex->sq_sig_all)
 		create_flags |= IB_UVERBS_QP_CREATE_SQ_SIG_ALL;
 

diff --git a/libibverbs/cmd_srq.c b/libibverbs/cmd_srq.c
@@ -53,6 +53,7 @@ static int ibv_icmd_create_srq(struct ibv_pd *pd, struct verbs_srq *vsrq,
 			       struct ibv_command_buffer *link)
 {
 	DECLARE_FBCMD_BUFFER(cmdb, UVERBS_OBJECT_SRQ, UVERBS_METHOD_SRQ_CREATE, 13, link);
+	struct verbs_ex_private *priv = get_priv(pd->context);
 	struct ib_uverbs_attr *handle;
 	uint32_t max_wr;
 	uint32_t max_sge;
@@ -107,6 +108,9 @@ static int ibv_icmd_create_srq(struct ibv_pd *pd, struct verbs_srq *vsrq,
 	fill_attr_out_ptr(cmdb, UVERBS_ATTR_CREATE_SRQ_RESP_MAX_WR, &max_wr);
 	fill_attr_out_ptr(cmdb, UVERBS_ATTR_CREATE_SRQ_RESP_MAX_SGE, &max_sge);
 
+	if (priv->imported)
+		fallback_require_ioctl(cmdb);
+
 	switch (execute_ioctl_fallback(srq->context, create_srq, cmdb, &ret)) {
 	case TRY_WRITE: {
 		if (attr_ex->srq_type == IBV_SRQT_BASIC && abi_ver > 5) {

diff --git a/libibverbs/cmd_wq.c b/libibverbs/cmd_wq.c
@@ -31,13 +31,15 @@
  */
 
 #include <infiniband/cmd_write.h>
+#include "ibverbs.h"
 
 static int ibv_icmd_create_wq(struct ibv_context *context,
 			      struct ibv_wq_init_attr *wq_init_attr,
 			      struct ibv_wq *wq,
 			      struct ibv_command_buffer *link)
 {
 	DECLARE_FBCMD_BUFFER(cmdb, UVERBS_OBJECT_WQ, UVERBS_METHOD_WQ_CREATE, 13, link);
+	struct verbs_ex_private *priv = get_priv(context);
 	struct ib_uverbs_attr *handle;
 	uint32_t max_wr;
 	uint32_t max_sge;
@@ -62,6 +64,8 @@ static int ibv_icmd_create_wq(struct ibv_context *context,
 	fill_attr_out_ptr(cmdb, UVERBS_ATTR_CREATE_WQ_RESP_MAX_SGE, &max_sge);
 	fill_attr_out_ptr(cmdb, UVERBS_ATTR_CREATE_WQ_RESP_WQ_NUM, &wq_num);
 
+	if (priv->imported)
+		fallback_require_ioctl(cmdb);
 	fallback_require_ex(cmdb);
 
 	switch (execute_ioctl_fallback(context, create_wq, cmdb, &ret)) {

diff --git a/libibverbs/device.c b/libibverbs/device.c
@@ -344,6 +344,7 @@ struct ibv_context *verbs_open_device(struct ibv_device *device, void *private_d
 	struct verbs_device *verbs_device = verbs_get_device(device);
 	int cmd_fd;
 	struct verbs_context *context_ex;
+	int ret;
 
 	/*
 	 * We'll only be doing writes, but we need O_RDWR in case the
@@ -363,6 +364,13 @@ struct ibv_context *verbs_open_device(struct ibv_device *device, void *private_d
 		return NULL;
 
 	set_lib_ops(context_ex);
+	if (context_ex->context.async_fd == -1) {
+		ret = ibv_cmd_alloc_async_fd(&context_ex->context);
+		if (ret) {
+			ibv_close_device(&context_ex->context);
+			return NULL;
+		}
+	}
 
 	return &context_ex->context;
 }

diff --git a/libibverbs/driver.h b/libibverbs/driver.h
@@ -453,6 +453,7 @@ int ibv_cmd_query_device_ex(struct ibv_context *context,
 int ibv_cmd_query_port(struct ibv_context *context, uint8_t port_num,
 		       struct ibv_port_attr *port_attr,
 		       struct ibv_query_port *cmd, size_t cmd_size);
+int ibv_cmd_alloc_async_fd(struct ibv_context *context);
 int ibv_cmd_alloc_pd(struct ibv_context *context, struct ibv_pd *pd,
 		     struct ibv_alloc_pd *cmd, size_t cmd_size,
 		     struct ib_uverbs_alloc_pd_resp *resp, size_t resp_size);

diff --git a/libibverbs/ibverbs.h b/libibverbs/ibverbs.h
@@ -74,6 +74,7 @@ struct verbs_ex_private {
 	uint32_t driver_id;
 	bool use_ioctl_write;
 	struct verbs_context_ops ops;
+	bool imported;
 };
 
 static inline struct verbs_ex_private *get_priv(struct ibv_context *ctx)