[PATCH 1/3] io_uring: add IOSQE_MULTI_CQES/REQ_F_MULTI_CQES for multishot requests

Hao Xu
2021-04-07T11:23:48Z

Since we now have requests that may generate multiple cqes, we need a
new flag to mark them, so that we can maintain features like drain io
easily for them.

Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
---
fs/io_uring.c | 5 ++++-
include/uapi/linux/io_uring.h | 3 +++
2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 81e5d156af1c..192463bb977a 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -102,7 +102,7 @@

#define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
- IOSQE_BUFFER_SELECT)
+ IOSQE_BUFFER_SELECT | IOSQE_MULTI_CQES)

struct io_uring {
u32 head ____cacheline_aligned_in_smp;
@@ -700,6 +700,7 @@ enum {
REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
+ REQ_F_MULTI_CQES_BIT = IOSQE_MULTI_CQES_BIT,

REQ_F_FAIL_LINK_BIT,
REQ_F_INFLIGHT_BIT,
@@ -766,6 +767,8 @@ enum {
REQ_F_ASYNC_WRITE = BIT(REQ_F_ASYNC_WRITE_BIT),
/* regular file */
REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
+ /* a request can generate multiple cqes */
+ REQ_F_MULTI_CQES = BIT(REQ_F_MULTI_CQES_BIT),
};

struct async_poll {
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 5beaa6bbc6db..303ac8005572 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -70,6 +70,7 @@ enum {
IOSQE_IO_HARDLINK_BIT,
IOSQE_ASYNC_BIT,
IOSQE_BUFFER_SELECT_BIT,
+ IOSQE_MULTI_CQES_BIT,
};

/*
@@ -87,6 +88,8 @@ enum {
#define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT)
/* select buffer from sqe->buf_group */
#define IOSQE_BUFFER_SELECT (1U << IOSQE_BUFFER_SELECT_BIT)
+/* may generate multiple cqes */
+#define IOSQE_MULTI_CQES (1U << IOSQE_MULTI_CQES_BIT)

/*
* io_uring_setup() flags
--
1.8.3.1