io_uring/zcrx: move area reg checks into io_import_area

io_import_area() is responsible for importing memory and parsing
io_uring_zcrx_area_reg, so move all area reg structure checks into the
function.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: isilence

io_uring/zcrx.c

@@ -26,6 +26,8 @@
 #include "zcrx.h"
 #include "rsrc.h"
 
+#define IO_ZCRX_AREA_SUPPORTED_FLAGS	(IORING_ZCRX_AREA_DMABUF)
+
 #define IO_DMA_ATTR (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING)
 
 static inline struct io_zcrx_ifq *io_pp_to_ifq(struct page_pool *pp)
@@ -231,6 +233,13 @@ static int io_import_area(struct io_zcrx_ifq *ifq,
 {
 	int ret;
 
+	if (area_reg->flags & ~IO_ZCRX_AREA_SUPPORTED_FLAGS)
+		return -EINVAL;
+	if (area_reg->rq_area_token)
+		return -EINVAL;
+	if (area_reg->__resv2[0] || area_reg->__resv2[1])
+		return -EINVAL;
+
 	ret = io_validate_user_buf_range(area_reg->addr, area_reg->len);
 	if (ret)
 		return ret;
@@ -395,8 +404,6 @@ static void io_zcrx_free_area(struct io_zcrx_area *area)
 	kfree(area);
 }
 
-#define IO_ZCRX_AREA_SUPPORTED_FLAGS	(IORING_ZCRX_AREA_DMABUF)
-
 static int io_zcrx_append_area(struct io_zcrx_ifq *ifq,
 				struct io_zcrx_area *area)
 {
@@ -413,13 +420,6 @@ static int io_zcrx_create_area(struct io_zcrx_ifq *ifq,
 	unsigned nr_iovs;
 	int i, ret;
 
-	if (area_reg->flags & ~IO_ZCRX_AREA_SUPPORTED_FLAGS)
-		return -EINVAL;
-	if (area_reg->rq_area_token)
-		return -EINVAL;
-	if (area_reg->__resv2[0] || area_reg->__resv2[1])
-		return -EINVAL;
-
 	ret = -ENOMEM;
 	area = kzalloc(sizeof(*area), GFP_KERNEL);
 	if (!area)