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| author | Dylan Yudaken <dylany@fb.com> | 2022-06-13 06:12:52 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-06-13 07:58:11 -0600 |
| commit | 9b02761ff329c80c90af874bbb1e97d8ca6f0575 (patch) | |
| tree | 0a60657885bed77a6382709d4005d035cbb2f37c | |
| parent | 2c9bc6ba8529c28da2b2afeffea88958ca315e5a (diff) | |
| download | liburing-9b02761ff329c80c90af874bbb1e97d8ca6f0575.tar.gz | |
add io_uring_buf_ring_init
Kernel expects the tail to start at 0, so provide an API to init the
ring appropriately.
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | man/io_uring_buf_ring_init.3 | 30 | ||||
| -rw-r--r-- | man/io_uring_register_buf_ring.3 | 5 | ||||
| -rw-r--r-- | src/include/liburing.h | 5 | ||||
| -rw-r--r-- | test/send_recvmsg.c | 1 |
4 files changed, 40 insertions, 1 deletions
diff --git a/man/io_uring_buf_ring_init.3 b/man/io_uring_buf_ring_init.3 new file mode 100644 index 0000000..50cf69a --- /dev/null +++ b/man/io_uring_buf_ring_init.3 @@ -0,0 +1,30 @@ +.\" Copyright (C) 2022 Dylan Yudaken <dylany@fb.com> +.\" +.\" SPDX-License-Identifier: LGPL-2.0-or-later +.\" +.TH io_uring_buf_ring_init 3 "June 13, 2022" "liburing-2.2" "liburing Manual" +.SH NAME +io_uring_buf_ring_init \- Initialise a buffer ring +.SH SYNOPSIS +.nf +.B #include <liburing.h> +.PP +.BI "void io_uring_buf_ring_init(struct io_uring_buf_ring *" br ");" +.fi +.SH DESCRIPTION +.PP +.BR io_uring_buf_ring_init (3) +initialises +.IR br +so that it is ready to be used. It may be called after +.BR io_uring_register_buf_ring (3) +but must be called before the buffer ring is used in any other way. + +.SH RETURN VALUE +None + +.SH SEE ALSO +.BR io_uring_register_buf_ring (3), +.BR io_uring_buf_ring_add (3) +.BR io_uring_buf_ring_advance (3), +.BR io_uring_buf_ring_cq_advance (3) diff --git a/man/io_uring_register_buf_ring.3 b/man/io_uring_register_buf_ring.3 index 9e0b53d..9e520bf 100644 --- a/man/io_uring_register_buf_ring.3 +++ b/man/io_uring_register_buf_ring.3 @@ -115,7 +115,9 @@ is the length of the buffer in bytes, and .I bid is the buffer ID that will be returned in the CQE once consumed. -Reserved fields must not be touched. Applications may use +Reserved fields must not be touched. Applications must use +.BR io_uring_buf_ring_init (3) +to initialise the buffer ring. Applications may use .BR io_uring_buf_ring_add (3) and .BR io_uring_buf_ring_advance (3) @@ -131,6 +133,7 @@ On success returns 0. On failure it returns .BR -errno . .SH SEE ALSO +.BR io_uring_buf_ring_init (3), .BR io_uring_buf_ring_add (3), .BR io_uring_buf_ring_advance (3), .BR io_uring_buf_ring_cq_advance (3) diff --git a/src/include/liburing.h b/src/include/liburing.h index 9beef0b..c31ece2 100644 --- a/src/include/liburing.h +++ b/src/include/liburing.h @@ -1097,6 +1097,11 @@ static inline int io_uring_buf_ring_mask(__u32 ring_entries) return ring_entries - 1; } +static inline void io_uring_buf_ring_init(struct io_uring_buf_ring *br) +{ + br->tail = 0; +} + /* * Assign 'buf' with the addr/len/buffer ID supplied */ diff --git a/test/send_recvmsg.c b/test/send_recvmsg.c index 6f18bae..cce6c45 100644 --- a/test/send_recvmsg.c +++ b/test/send_recvmsg.c @@ -199,6 +199,7 @@ static void *recv_fn(void *data) } br = ptr; + io_uring_buf_ring_init(br); io_uring_buf_ring_add(br, buf, sizeof(buf), BUF_BID, io_uring_buf_ring_mask(1), 0); io_uring_buf_ring_advance(br, 1); |