From 2bb04df7c2af9dad5d28771c723bc39b01cf7df4 Mon Sep 17 00:00:00 2001
From: Stefan Roesch <shr@fb.com>
Date: Tue, 26 Apr 2022 11:21:34 -0700
Subject: [PATCH] io_uring: support CQE32 for nop operation
Git-commit: 2bb04df7c2af9dad5d28771c723bc39b01cf7df4
Patch-mainline: v5.19-rc1
References: bsc#1205205

This adds support for filling the extra1 and extra2 fields for large
CQE's.

Co-developed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Stefan Roesch <shr@fb.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20220426182134.136504-13-shr@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
---
 fs/io_uring.c |   27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -758,6 +758,12 @@ struct io_msg {
 	u32 len;
 };
 
+struct io_nop {
+	struct file			*file;
+	u64				extra1;
+	u64				extra2;
+};
+
 struct io_async_connect {
 	struct sockaddr_storage		address;
 };
@@ -951,6 +957,7 @@ struct io_kiocb {
 		struct io_symlink	symlink;
 		struct io_hardlink	hardlink;
 		struct io_msg		msg;
+		struct io_nop           nop;
 	};
 
 	u8				opcode;
@@ -4726,6 +4733,19 @@ done:
 	return 0;
 }
 
+static int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+	/*
+	 * If the ring is setup with CQE32, relay back addr/addr
+	 */
+	if (req->ctx->flags & IORING_SETUP_CQE32) {
+		req->nop.extra1 = READ_ONCE(sqe->addr);
+		req->nop.extra2 = READ_ONCE(sqe->addr2);
+	}
+
+	return 0;
+}
+
 /*
  * IORING_OP_NOP just posts a completion event, nothing else.
  */
@@ -4742,6 +4762,11 @@ static int io_nop(struct io_kiocb *req,
 	}
 
 	__io_req_complete(req, issue_flags, 0, io_put_kbuf(req, issue_flags));
+	if (!(req->ctx->flags & IORING_SETUP_CQE32))
+		__io_req_complete(req, issue_flags, 0, 0);
+	else
+		__io_req_complete32(req, issue_flags, 0, 0, req->nop.extra1,
+				    req->nop.extra2);
 	return 0;
 }
 
@@ -7393,7 +7418,7 @@ static int io_req_prep(struct io_kiocb *
 {
 	switch (req->opcode) {
 	case IORING_OP_NOP:
-		return 0;
+		return io_nop_prep(req, sqe);
 	case IORING_OP_READV:
 	case IORING_OP_READ_FIXED:
 	case IORING_OP_READ: