user/sven/linux.git/include/uapi/linux/io_uring.h, branch v5.13.16

io_uring: add feature flag for rsrc tags

2021-06-10T22:33:51Z

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

2021-06-10T22:33:51Z

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

2021-04-25T16:14:04Z

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

2021-04-25T16:14:04Z

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

2021-04-25T16:14:04Z

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

2021-04-25T16:14:04Z

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

2021-04-11T23:42:00Z

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

2021-04-11T23:41:59Z

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

io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS

2021-02-24T03:32:11Z

A few reasons to do this: - The naming of the manager and worker have changed. That's a user visible change, so makes sense to flag it. - Opening certain files that use ->signal (like /proc/self or /dev/tty) now works, and the flag tells the application upfront that this is the case. - Related to the above, using signalfd will now work as well. Signed-off-by: Jens Axboe

io_uring: Add skip option for __io_sqe_files_update

2021-02-01T17:02:43Z

This patch adds support for skipping a file descriptor when using IORING_REGISTER_FILES_UPDATE. __io_sqe_files_update will skip fds set to IORING_REGISTER_FILES_SKIP. IORING_REGISTER_FILES_SKIP is inturn added as a #define in io_uring.h Signed-off-by: noah Signed-off-by: Jens Axboe