[PATCH v2 01/12] io_uring: support CQE32 in io_uring_cqe

[Stefan Roesch <shr@fb.com>]

This adds the struct io_uring_cqe_extra in the structure io_uring_cqe to
support large CQE's.

Co-developed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Stefan Roesch <shr@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 include/uapi/linux/io_uring.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index ee677dbd6a6d..c0e9b5e8d20c 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -111,6 +111,7 @@ enum {
 #define IORING_SETUP_R_DISABLED	(1U << 6)	/* start with ring disabled */
 #define IORING_SETUP_SUBMIT_ALL	(1U << 7)	/* continue submit on error */
 #define IORING_SETUP_SQE128	(1U << 8)	/* SQEs are 128b */
+#define IORING_SETUP_CQE32	(1U << 9)	/* CQEs are 32b */
 
 enum {
 	IORING_OP_NOP,
@@ -201,6 +202,11 @@ enum {
 #define IORING_POLL_UPDATE_EVENTS	(1U << 1)
 #define IORING_POLL_UPDATE_USER_DATA	(1U << 2)
 
+struct io_uring_cqe_extra {
+	__u64	extra1;
+	__u64	extra2;
+};
+
 /*
  * IO completion data structure (Completion Queue Entry)
  */
@@ -208,6 +214,12 @@ struct io_uring_cqe {
 	__u64	user_data;	/* sqe->data submission passed back */
 	__s32	res;		/* result code for this event */
 	__u32	flags;
+
+	/*
+	 * If the ring is initialized with IORING_SETUP_CQE32, then this field
+	 * contains 16-bytes of padding, doubling the size of the CQE.
+	 */
+	struct io_uring_cqe_extra	b[];
 };
 
 /*
-- 
2.30.2