io_uring: add REQ_F_APOLL_MULTISHOT for requests

Add a flag to indicate multishot mode for fast poll. currently only
accept use it, but there may be more operations leveraging it in the
future. Also add a mask IO_APOLL_MULTI_POLLED which stands for
REQ_F_APOLL_MULTI | REQ_F_POLLED, to make the code short and cleaner.

Signed-off-by: Hao Xu <howeyxu@tencent.com>
Link: https://lore.kernel.org/r/20220514142046.58072-3-haoxu.linux@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index c4bd0faf0b274034ac260a2dffb34f7d394438d1..e1e550de59566887449ffd4fc0c69d79b0883e3a 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -116,6 +116,8 @@
 #define IO_REQ_CLEAN_SLOW_FLAGS (REQ_F_REFCOUNT | REQ_F_LINK | REQ_F_HARDLINK |\
                                 IO_REQ_CLEAN_FLAGS)
 
+#define IO_APOLL_MULTI_POLLED (REQ_F_APOLL_MULTISHOT | REQ_F_POLLED)
+
 #define IO_TCTX_REFS_CACHE_NR  (1U << 10)
 
 struct io_uring {
@@ -812,6 +814,7 @@ enum {
        REQ_F_SINGLE_POLL_BIT,
        REQ_F_DOUBLE_POLL_BIT,
        REQ_F_PARTIAL_IO_BIT,
+       REQ_F_APOLL_MULTISHOT_BIT,
        /* keep async read/write and isreg together and in order */
        REQ_F_SUPPORT_NOWAIT_BIT,
        REQ_F_ISREG_BIT,
@@ -876,6 +879,8 @@ enum {
        REQ_F_DOUBLE_POLL       = BIT(REQ_F_DOUBLE_POLL_BIT),
        /* request has already done partial IO */
        REQ_F_PARTIAL_IO        = BIT(REQ_F_PARTIAL_IO_BIT),
+       /* fast poll multishot mode */
+       REQ_F_APOLL_MULTISHOT   = BIT(REQ_F_APOLL_MULTISHOT_BIT),
 };
 
 struct async_poll {