[PATCH 4/6] Revert "io_uring: always go async for unsupported fadvise flags"

[Jens Axboe <axboe@kernel.dk>]

This reverts commit c31cc60fddd11134031e7f9eb76812353cfaac84.

In preparation for handling this a bit differently, revert this
cleanup.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 io_uring/advise.c | 25 ++++++++++---------------
 1 file changed, 10 insertions(+), 15 deletions(-)

diff --git a/io_uring/advise.c b/io_uring/advise.c
index 7085804c513c..cf600579bffe 100644
--- a/io_uring/advise.c
+++ b/io_uring/advise.c
@@ -62,18 +62,6 @@ int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
 #endif
 }
 
-static bool io_fadvise_force_async(struct io_fadvise *fa)
-{
-	switch (fa->advice) {
-	case POSIX_FADV_NORMAL:
-	case POSIX_FADV_RANDOM:
-	case POSIX_FADV_SEQUENTIAL:
-		return false;
-	default:
-		return true;
-	}
-}
-
 int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	struct io_fadvise *fa = io_kiocb_to_cmd(req, struct io_fadvise);
@@ -84,8 +72,6 @@ int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	fa->offset = READ_ONCE(sqe->off);
 	fa->len = READ_ONCE(sqe->len);
 	fa->advice = READ_ONCE(sqe->fadvise_advice);
-	if (io_fadvise_force_async(fa))
-		req->flags |= REQ_F_FORCE_ASYNC;
 	return 0;
 }
 
@@ -94,7 +80,16 @@ int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
 	struct io_fadvise *fa = io_kiocb_to_cmd(req, struct io_fadvise);
 	int ret;
 
-	WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK && io_fadvise_force_async(fa));
+	if (issue_flags & IO_URING_F_NONBLOCK) {
+		switch (fa->advice) {
+		case POSIX_FADV_NORMAL:
+		case POSIX_FADV_RANDOM:
+		case POSIX_FADV_SEQUENTIAL:
+			break;
+		default:
+			return -EAGAIN;
+		}
+	}
 
 	ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
 	if (ret < 0)
-- 
2.39.2