From 7d3fd88d61a41016da01889f076fd1c60c7298fc Mon Sep 17 00:00:00 2001 From: Josh Triplett Date: Tue, 14 Feb 2023 16:42:22 -0800 Subject: io_uring: Support calling io_uring_register with a registered ring fd Add a new flag IORING_REGISTER_USE_REGISTERED_RING (set via the high bit of the opcode) to treat the fd as a registered index rather than a file descriptor. This makes it possible for a library to open an io_uring, register the ring fd, close the ring fd, and subsequently use the ring entirely via registered index. Signed-off-by: Josh Triplett Link: https://lore.kernel.org/r/f2396369e638284586b069dbddffb8c992afba95.1676419314.git.josh@joshtriplett.org [axboe: remove extra high bit clear] Signed-off-by: Jens Axboe --- include/uapi/linux/io_uring.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 636a4c2c1294..97661a60b28c 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -472,6 +472,7 @@ struct io_uring_params { #define IORING_FEAT_RSRC_TAGS (1U << 10) #define IORING_FEAT_CQE_SKIP (1U << 11) #define IORING_FEAT_LINKED_FILE (1U << 12) +#define IORING_FEAT_REG_REG_RING (1U << 13) /* * io_uring_register(2) opcodes and arguments @@ -519,7 +520,10 @@ enum { IORING_REGISTER_FILE_ALLOC_RANGE = 25, /* this goes last */ - IORING_REGISTER_LAST + IORING_REGISTER_LAST, + + /* flag added to the opcode to use a registered ring fd */ + IORING_REGISTER_USE_REGISTERED_RING = 1U << 31 }; /* io-wq worker categories */ -- cgit v1.2.3