RDMA/uverbs: Add support for UCAPs in context creation

Add support for file descriptor array attribute for GET_CONTEXT
commands.

Check that the file descriptor (fd) array represents fds for valid UCAPs.
Store the enabled UCAPs from the fd array as a bitmask in ib_ucontext.

Signed-off-by: Chiara Meiohas <cmeiohas@nvidia.com>
Link: https://patch.msgid.link/ebfb30bc947e2259b193c96a319c80e82599045b.1741261611.git.leon@kernel.org
Reviewed-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

Author: chiarameiohas

drivers/infiniband/core/uverbs_cmd.c

@@ -42,6 +42,7 @@
 
 #include <rdma/uverbs_types.h>
 #include <rdma/uverbs_std_types.h>
+#include <rdma/ib_ucaps.h>
 #include "rdma_core.h"
 
 #include "uverbs.h"
@@ -232,6 +233,8 @@ int ib_init_ucontext(struct uverbs_attr_bundle *attrs)
 {
 	struct ib_ucontext *ucontext = attrs->context;
 	struct ib_uverbs_file *file = attrs->ufile;
+	int *fd_array;
+	int fd_count;
 	int ret;
 
 	if (!down_read_trylock(&file->hw_destroy_rwsem))
@@ -247,6 +250,22 @@ int ib_init_ucontext(struct uverbs_attr_bundle *attrs)
 	if (ret)
 		goto err;
 
+	if (uverbs_attr_is_valid(attrs, UVERBS_ATTR_GET_CONTEXT_FD_ARR)) {
+		fd_count = uverbs_attr_ptr_get_array_size(attrs,
+							  UVERBS_ATTR_GET_CONTEXT_FD_ARR,
+							  sizeof(int));
+		if (fd_count < 0) {
+			ret = fd_count;
+			goto err_uncharge;
+		}
+
+		fd_array = uverbs_attr_get_alloced_ptr(attrs,
+						       UVERBS_ATTR_GET_CONTEXT_FD_ARR);
+		ret = ib_get_ucaps(fd_array, fd_count, &ucontext->enabled_caps);
+		if (ret)
+			goto err_uncharge;
+	}
+
 	ret = ucontext->device->ops.alloc_ucontext(ucontext,
 						   &attrs->driver_udata);
 	if (ret)

drivers/infiniband/core/uverbs_std_types_device.c

@@ -437,6 +437,10 @@ DECLARE_UVERBS_NAMED_METHOD(
 			    UVERBS_ATTR_TYPE(u32), UA_OPTIONAL),
 	UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_GET_CONTEXT_CORE_SUPPORT,
 			    UVERBS_ATTR_TYPE(u64), UA_OPTIONAL),
+	UVERBS_ATTR_PTR_IN(UVERBS_ATTR_GET_CONTEXT_FD_ARR,
+			   UVERBS_ATTR_MIN_SIZE(sizeof(int)),
+			   UA_OPTIONAL,
+			   UA_ALLOC_AND_COPY),
 	UVERBS_ATTR_UHW());
 
 DECLARE_UVERBS_NAMED_METHOD(

include/rdma/ib_verbs.h

@@ -1530,6 +1530,7 @@ struct ib_ucontext {
 	struct ib_uverbs_file  *ufile;
 
 	struct ib_rdmacg_object	cg_obj;
+	u64 enabled_caps;
 	/*
 	 * Implementation details of the RDMA core, don't use in drivers:
 	 */

include/uapi/rdma/ib_user_ioctl_cmds.h

@@ -88,6 +88,7 @@ enum uverbs_attrs_query_port_cmd_attr_ids {
 enum uverbs_attrs_get_context_attr_ids {
 	UVERBS_ATTR_GET_CONTEXT_NUM_COMP_VECTORS,
 	UVERBS_ATTR_GET_CONTEXT_CORE_SUPPORT,
+	UVERBS_ATTR_GET_CONTEXT_FD_ARR,
 };
 
 enum uverbs_attrs_query_context_attr_ids {