BMC/Intel-BMC/linux.git/include/uapi/linux/io_uring.h, branch dev-5.14-intel

io_uring: simplify struct io_uring_sqe layout

2021-06-30T20:15:39+00:00

Flatten struct io_uring_sqe, the last union is exactly 64B, so move them out of union { struct { ... }}, and decrease __pad2 size. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/2e21ef7aed136293d654450bc3088973a8adc730.1624543113.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: allow user configurable IO thread CPU affinity

2021-06-17T16:25:50+00:00

io-wq defaults to per-node masks for IO workers. This works fine by default, but isn't particularly handy for workloads that prefer more specific affinities, for either performance or isolation reasons. This adds IORING_REGISTER_IOWQ_AFF that allows the user to pass in a CPU mask that is then applied to IO thread workers, and an IORING_UNREGISTER_IOWQ_AFF that simply resets the masks back to the default of per-node. Note that no care is given to existing IO threads, they will need to go through a reschedule before the affinity is correct if they are already running or sleeping. Signed-off-by: Jens Axboe

io_uring: add feature flag for rsrc tags

2021-06-10T22:33:51+00:00

Add IORING_FEAT_RSRC_TAGS indicating that io_uring supports a bunch of new IORING_REGISTER operations, in particular IORING_REGISTER_[FILES[,UPDATE]2,BUFFERS[2,UPDATE]] that support rsrc tagging, and also indicating implemented dynamic fixed buffer updates. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/9b995d4045b6c6b4ab7510ca124fd25ac2203af7.1623339162.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: change registration/upd/rsrc tagging ABI

2021-06-10T22:33:51+00:00

There are ABI moments about recently added rsrc registration/update and tagging that might become a nuisance in the future. First, IORING_REGISTER_RSRC[_UPD] hide different types of resources under it, so breaks fine control over them by restrictions. It works for now, but once those are wanted under restrictions it would require a rework. It was also inconvenient trying to fit a new resource not supporting all the features (e.g. dynamic update) into the interface, so better to return to IORING_REGISTER_* top level dispatching. Second, register/update were considered to accept a type of resource, however that's not a good idea because there might be several ways of registration of a single resource type, e.g. we may want to add non-contig buffers or anything more exquisite as dma mapped memory. So, remove IORING_RSRC_[FILE,BUFFER] out of the ABI, and place them internally for now to limit changes. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/9b554897a7c17ad6e3becc48dfed2f7af9f423d5.1623339162.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: add full-fledged dynamic buffers support

2021-04-25T16:14:04+00:00

Hook buffers into all rsrc infrastructure, including tagging and updates. Suggested-by: Bijan Mottahedeh Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/119ed51d68a491dae87eb55fb467a47870c86aad.1619356238.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: add generic rsrc update with tags

2021-04-25T16:14:04+00:00

Add IORING_REGISTER_RSRC_UPDATE, which also supports passing in rsrc tags. Implement it for registered files. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/d4dc66df204212f64835ffca2c4eb5e8363f2f05.1619356238.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: add IORING_REGISTER_RSRC

2021-04-25T16:14:04+00:00

Add a new io_uring_register() opcode for rsrc registeration. Instead of accepting a pointer to resources, fds or iovecs, it @arg is now pointing to a struct io_uring_rsrc_register, and the second argument tells how large that struct is to make it easily extendible by adding new fields. All that is done mainly to be able to pass in a pointer with tags. Pass it in and enable CQE posting for file resources. Doesn't support setting tags on update yet. A design choice made here is to not post CQEs on rsrc de-registration, but only when we updated-removed it by rsrc dynamic update. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/c498aaec32a4bb277b2406b9069662c02cdda98c.1619356238.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: enumerate dynamic resources

2021-04-25T16:14:04+00:00

As resources are getting more support and common parts, it'll be more convenient to index resources and use it for indexing. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/f0be63e9310212d5601d36277c2946ff7a040485.1619356238.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: allow events and user_data update of running poll requests

2021-04-11T23:42:00+00:00

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

io_uring: add multishot mode for IORING_OP_POLL_ADD

2021-04-11T23:41:59+00:00

The default io_uring poll mode is one-shot, where once the event triggers, the poll command is completed and won't trigger any further events. If we're doing repeated polling on the same file or socket, then it can be more efficient to do multishot, where we keep triggering whenever the event becomes true. This deviates from the usual norm of having one CQE per SQE submitted. Add a CQE flag, IORING_CQE_F_MORE, which tells the application to expect further completion events from the submitted SQE. Right now the only user of this is POLL_ADD in multishot mode. Since sqe->poll_events is using the space that we normally use for adding flags to commands, use sqe->len for the flag space for POLL_ADD. Multishot mode is selected by setting IORING_POLL_ADD_MULTI in sqe->len. An application should expect more CQEs for the specificed SQE if the CQE is flagged with IORING_CQE_F_MORE. In multishot mode, only cancelation or an error will terminate the poll request, in which case the flag will be cleared. Signed-off-by: Jens Axboe