[PATCH v2 1/1] io_uring: extract the function that checks the legitimacy of sq/cq entries

[Xin Wang <yw987194828@gmail.com>]

In the io_uring_create function, the sq_entries and cq_entries passed
in by the user are examined. The checking logic is the same for both, so
the common code can be extracted for reuse.

Extract the common code as io_validate_entries function.

Changes:
V1->V2::
  - Replace function name 'io_validate_entries' with 'io_validate_ring_entries'
    to enhance readability.
  - Removed unnecessary parentheses.
  - Line Wrapping.

====================

Signed-off-by: Xin Wang <yw987194828@gmail.com>
---
 io_uring/io_uring.c | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index cd9a137ad6ce..4c3580229283 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -3819,6 +3819,19 @@ static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
 					 O_RDWR | O_CLOEXEC, NULL);
 }
 
+static bool io_validate_ring_entries(unsigned int *entries,
+				     unsigned int max_entries, __u32 flags)
+{
+	if (!*entries)
+		return false;
+	if (*entries > max_entries) {
+		if (!(flags & IORING_SETUP_CLAMP))
+			return false;
+		*entries = max_entries;
+	}
+	return true;
+}
+
 static __cold int io_uring_create(unsigned entries, struct io_uring_params *p,
 				  struct io_uring_params __user *params)
 {
@@ -3827,13 +3840,8 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p,
 	struct file *file;
 	int ret;
 
-	if (!entries)
+	if (!io_validate_ring_entries(&entries, IORING_MAX_ENTRIES, p->flags))
 		return -EINVAL;
-	if (entries > IORING_MAX_ENTRIES) {
-		if (!(p->flags & IORING_SETUP_CLAMP))
-			return -EINVAL;
-		entries = IORING_MAX_ENTRIES;
-	}
 
 	if ((p->flags & IORING_SETUP_REGISTERED_FD_ONLY)
 	    && !(p->flags & IORING_SETUP_NO_MMAP))
@@ -3854,13 +3862,8 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p,
 		 * to a power-of-two, if it isn't already. We do NOT impose
 		 * any cq vs sq ring sizing.
 		 */
-		if (!p->cq_entries)
+		if (!io_validate_ring_entries(&p->cq_entries, IORING_MAX_CQ_ENTRIES, p->flags))
 			return -EINVAL;
-		if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
-			if (!(p->flags & IORING_SETUP_CLAMP))
-				return -EINVAL;
-			p->cq_entries = IORING_MAX_CQ_ENTRIES;
-		}
 		p->cq_entries = roundup_pow_of_two(p->cq_entries);
 		if (p->cq_entries < p->sq_entries)
 			return -EINVAL;
-- 
2.25.1