From b69de288e913030082bed3a324ddc58be6c1e983 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 17 Mar 2021 08:37:41 -0600 Subject: io_uring: allow events and user_data update of running poll requests This adds two new POLL_ADD flags, IORING_POLL_UPDATE_EVENTS and IORING_POLL_UPDATE_USER_DATA. As with the other POLL_ADD flag, these are masked into sqe->len. If set, the POLL_ADD will have the following behavior: - sqe->addr must contain the the user_data of the poll request that needs to be modified. This field is otherwise invalid for a POLL_ADD command. - If IORING_POLL_UPDATE_EVENTS is set, sqe->poll_events must contain the new mask for the existing poll request. There are no checks for whether these are identical or not, if a matching poll request is found, then it is re-armed with the new mask. - If IORING_POLL_UPDATE_USER_DATA is set, sqe->off must contain the new user_data for the existing poll request. A POLL_ADD with any of these flags set may complete with any of the following results: 1) 0, which means that we successfully found the existing poll request specified, and performed the re-arm procedure. Any error from that re-arm will be exposed as a completion event for that original poll request, not for the update request. 2) -ENOENT, if no existing poll request was found with the given user_data. 3) -EALREADY, if the existing poll request was already in the process of being removed/canceled/completing. 4) -EACCES, if an attempt was made to modify an internal poll request (eg not one originally issued ass IORING_OP_POLL_ADD). The usual -EINVAL cases apply as well, if any invalid fields are set in the sqe for this command type. Signed-off-by: Jens Axboe --- include/uapi/linux/io_uring.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/uapi/linux/io_uring.h') diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 76c967621601..5beaa6bbc6db 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -166,8 +166,13 @@ enum { * IORING_POLL_ADD_MULTI Multishot poll. Sets IORING_CQE_F_MORE if * the poll handler will continue to report * CQEs on behalf of the same SQE. + * + * IORING_POLL_UPDATE Update existing poll request, matching + * sqe->addr as the old user_data field. */ #define IORING_POLL_ADD_MULTI (1U << 0) +#define IORING_POLL_UPDATE_EVENTS (1U << 1) +#define IORING_POLL_UPDATE_USER_DATA (1U << 2) /* * IO completion data structure (Completion Queue Entry) -- cgit v1.2.3