kernel/git/stable/linux.git/fs/io-wq.h, branch master

io_uring: move to separate directory

2022-07-25T00:39:10+00:00

In preparation for splitting io_uring up a bit, move it into its own top level directory. It didn't really belong in fs/ anyway, as it's not a file system only API. This adds io_uring/ and moves the core files in there, and updates the MAINTAINERS file for the new location. Signed-off-by: Jens Axboe

io_uring: add support for IORING_ASYNC_CANCEL_ALL

2022-04-25T00:18:18+00:00

The current cancelation will lookup and cancel the first request it finds based on the key passed in. Add a flag that allows to cancel any request that matches they key. It completes with the number of requests found and canceled, or res < 0 if an error occured. Signed-off-by: Jens Axboe Link: https://lore.kernel.org/r/20220418164402.75259-4-axboe@kernel.dk

io_uring: stop using io_wq_work as an fd placeholder

2022-04-11T23:06:20+00:00

There are two reasons why this isn't the best idea: - It's an odd area to grab a bit of storage space, hence it's an odd area to grab storage from. - It puts the 3rd io_kiocb cacheline into the hot path, where normal hot path just needs the first two. Use 'cflags' for joint fd/cflags storage. We only need fd until we successfully issue, and we only need cflags once a request is done and is completed. Fixes: 6bf9c47a3989 ("io_uring: defer file assignment") Signed-off-by: Jens Axboe

io_uring: defer file assignment

2022-04-07T17:17:28+00:00

If an application uses direct open or accept, it knows in advance what direct descriptor value it will get as it picks it itself. This allows combined requests such as: sqe = io_uring_get_sqe(ring); io_uring_prep_openat_direct(sqe, ..., file_slot); sqe->flags |= IOSQE_IO_LINK | IOSQE_CQE_SKIP_SUCCESS; sqe = io_uring_get_sqe(ring); io_uring_prep_read(sqe,file_slot, buf, buf_size, 0); sqe->flags |= IOSQE_FIXED_FILE; io_uring_submit(ring); where we prepare both a file open and read, and only get a completion event for the read when both have completed successfully. Currently links are fully prepared before the head is issued, but that fails if the dependent link needs a file assigned that isn't valid until the head has completed. Conversely, if the same chain is performed but the fixed file slot is already valid, then we would be unexpectedly returning data from the old file slot rather than the newly opened one. Make sure we're consistent here. Allow deferral of file setup, which makes this documented case work. Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Jens Axboe

Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2022-01-17T03:49:30+00:00

Pull signal/exit/ptrace updates from Eric Biederman: "This set of changes deletes some dead code, makes a lot of cleanups which hopefully make the code easier to follow, and fixes bugs found along the way. The end-game which I have not yet reached yet is for fatal signals that generate coredumps to be short-circuit deliverable from complete_signal, for force_siginfo_to_task not to require changing userspace configured signal delivery state, and for the ptrace stops to always happen in locations where we can guarantee on all architectures that the all of the registers are saved and available on the stack. Removal of profile_task_ext, profile_munmap, and profile_handoff_task are the big successes for dead code removal this round. A bunch of small bug fixes are included, as most of the issues reported were small enough that they would not affect bisection so I simply added the fixes and did not fold the fixes into the changes they were fixing. There was a bug that broke coredumps piped to systemd-coredump. I dropped the change that caused that bug and replaced it entirely with something much more restrained. Unfortunately that required some rebasing. Some successes after this set of changes: There are few enough calls to do_exit to audit in a reasonable amount of time. The lifetime of struct kthread now matches the lifetime of struct task, and the pointer to struct kthread is no longer stored in set_child_tid. The flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is removed. Issues where task->exit_code was examined with signal->group_exit_code should been examined were fixed. There are several loosely related changes included because I am cleaning up and if I don't include them they will probably get lost. The original postings of these changes can be found at: https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org I trimmed back the last set of changes to only the obviously correct once. Simply because there was less time for review than I had hoped" * 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits) ptrace/m68k: Stop open coding ptrace_report_syscall ptrace: Remove unused regs argument from ptrace_report_syscall ptrace: Remove second setting of PT_SEIZED in ptrace_attach taskstats: Cleanup the use of task->exit_code exit: Use the correct exit_code in /proc//stat exit: Fix the exit_code for wait_task_zombie exit: Coredumps reach do_group_exit exit: Remove profile_handoff_task exit: Remove profile_task_exit & profile_munmap signal: clean up kernel-doc comments signal: Remove the helper signal_group_exit signal: Rename group_exit_task group_exec_task coredump: Stop setting signal->group_exit_task signal: Remove SIGNAL_GROUP_COREDUMP signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process signal: Make coredump handling explicit in complete_signal signal: Have prepare_signal detect coredumps using signal->core_state signal: Have the oom killer detect coredumps using signal->core_state exit: Move force_uaccess back into do_exit exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit ...

kthread: Generalize pf_io_worker so it can point to struct kthread

2022-01-08T15:39:49+00:00

The point of using set_child_tid to hold the kthread pointer was that it already did what is necessary. There are now restrictions on when set_child_tid can be initialized and when set_child_tid can be used in schedule_tail. Which indicates that continuing to use set_child_tid to hold the kthread pointer is a bad idea. Instead of continuing to use the set_child_tid field of task_struct generalize the pf_io_worker field of task_struct and use it to hold the kthread pointer. Rename pf_io_worker (which is a void * pointer) to worker_private so it can be used to store kthreads struct kthread pointer. Update the kthread code to store the kthread pointer in the worker_private field. Remove the places where set_child_tid had to be dealt with carefully because kthreads also used it. Link: https://lkml.kernel.org/r/CAHk-=wgtFAA9SbVYg0gR1tqPMC17-NYcs0GQkaYg1bGhh1uJQQ@mail.gmail.com Link: https://lkml.kernel.org/r/87a6grvqy8.fsf_-_@email.froward.int.ebiederm.org Suggested-by: Linus Torvalds Signed-off-by: "Eric W. Biederman"

io-wq: add helper to merge two wq_lists

2021-12-07T22:01:57+00:00

add a helper to merge two wq_lists, it will be useful in the next patches. Reviewed-by: Pavel Begunkov Signed-off-by: Hao Xu Link: https://lore.kernel.org/r/20211207093951.247840-2-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe

io_uring: optimise INIT_WQ_LIST

2021-10-19T11:49:54+00:00

The invariant of io_wq_work_list is that it's empty IFF ->first is NULL, so no need to initially set ->last. With now having more users of the list it may play a role, i.e. used in each tw iteration and on every completion flushing. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/c464ab5cab6e46a858c6d39c107e92b3b5291f13.1633373302.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: use single linked list for iopoll

2021-10-19T11:49:53+00:00

Use single linked lists for keeping iopoll requests, takes less space, may be faster, but mostly will be of benefit for further patches. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/314033676b100cd485518c3bc55e1b95a0dcd71f.1632516769.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io-wq: add io_wq_work_node based stack

2021-10-19T11:49:53+00:00

Apart from just using lists (i.e. io_wq_work_list), we also want to have stacks, which are a bit faster, and have some interoperability between them. Add a stack implementation based on io_wq_work_node and some helpers. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/5d3a412a5ac0d47e0f0499d70d2207d70a68925e.1632516769.git.asml.silence@gmail.com Signed-off-by: Jens Axboe