[PATCH for-next 3/4] io-uring: add recycle_async to ops

[Dylan Yudaken <dylany@fb.com>]

Some ops recycle or cache async data when they are done.
Build this into the framework for async data so that we can rely on
io_uring to know when a request is done (rather than doing it inline in a
handler).

Signed-off-by: Dylan Yudaken <dylany@fb.com>
---
 io_uring/io_uring.c | 8 ++++++--
 io_uring/opdef.h    | 1 +
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 32110c5b4059..3e9fdaf9c72c 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1578,8 +1578,12 @@ static void io_clean_op(struct io_kiocb *req)
 	if (req->flags & REQ_F_CREDS)
 		put_cred(req->creds);
 	if (req->flags & REQ_F_ASYNC_DATA) {
-		kfree(req->async_data);
-		req->async_data = NULL;
+		const struct io_op_def *def = &io_op_defs[req->opcode];
+
+		if (!(def->recycle_async && def->recycle_async(req))) {
+			kfree(req->async_data);
+			req->async_data = NULL;
+		}
 	}
 	req->flags &= ~IO_REQ_CLEAN_FLAGS;
 }
diff --git a/io_uring/opdef.h b/io_uring/opdef.h
index ece8ed4f96c4..3de64731fc5f 100644
--- a/io_uring/opdef.h
+++ b/io_uring/opdef.h
@@ -34,6 +34,7 @@ struct io_op_def {
 	int (*issue)(struct io_kiocb *, unsigned int);
 	int (*prep_async)(struct io_kiocb *);
 	void (*cleanup)(struct io_kiocb *);
+	bool (*recycle_async)(struct io_kiocb *);
 };
 
 extern const struct io_op_def io_op_defs[];
-- 
2.30.2