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* io_uring: zero iocb->ki_pos for stream file typesJens Axboe2021-12-231-3/+7
| | | | | | | | | | | | | | | | io_uring supports using offset == -1 for using the current file position, and we read that in as part of read/write command setup. For the non-iter read/write types we pass in NULL for the position pointer, but for the iter types we should not be passing any anything but 0 for the position for a stream. Clear kiocb->ki_pos if the file is a stream, don't leave it as -1. If we do, then the request will error with -ESPIPE. Fixes: ba04291eb66e ("io_uring: allow use of offset == -1 to mean file position") Link: https://github.com/axboe/liburing/discussions/501 Reported-by: Samuel Williams <samuel.williams@oriontransfer.co.nz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: ensure task_work gets run as part of cancelationsJens Axboe2021-12-101-2/+4
| | | | | | | | | | | | | | If we successfully cancel a work item but that work item needs to be processed through task_work, then we can be sleeping uninterruptibly in io_uring_cancel_generic() and never process it. Hence we don't make forward progress and we end up with an uninterruptible sleep warning. While in there, correct a comment that should be IFF, not IIF. Reported-and-tested-by: syzbot+21e6887c0be14181206d@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: Fix undefined-behaviour in io_issue_sqeYe Bin2021-11-271-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We got issue as follows: ================================================================================ UBSAN: Undefined behaviour in ./include/linux/ktime.h:42:14 signed integer overflow: -4966321760114568020 * 1000000000 cannot be represented in type 'long long int' CPU: 1 PID: 2186 Comm: syz-executor.2 Not tainted 4.19.90+ #12 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78 show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x170/0x1dc lib/dump_stack.c:118 ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161 handle_overflow+0x188/0x1dc lib/ubsan.c:192 __ubsan_handle_mul_overflow+0x34/0x44 lib/ubsan.c:213 ktime_set include/linux/ktime.h:42 [inline] timespec64_to_ktime include/linux/ktime.h:78 [inline] io_timeout fs/io_uring.c:5153 [inline] io_issue_sqe+0x42c8/0x4550 fs/io_uring.c:5599 __io_queue_sqe+0x1b0/0xbc0 fs/io_uring.c:5988 io_queue_sqe+0x1ac/0x248 fs/io_uring.c:6067 io_submit_sqe fs/io_uring.c:6137 [inline] io_submit_sqes+0xed8/0x1c88 fs/io_uring.c:6331 __do_sys_io_uring_enter fs/io_uring.c:8170 [inline] __se_sys_io_uring_enter fs/io_uring.c:8129 [inline] __arm64_sys_io_uring_enter+0x490/0x980 fs/io_uring.c:8129 invoke_syscall arch/arm64/kernel/syscall.c:53 [inline] el0_svc_common+0x374/0x570 arch/arm64/kernel/syscall.c:121 el0_svc_handler+0x190/0x260 arch/arm64/kernel/syscall.c:190 el0_svc+0x10/0x218 arch/arm64/kernel/entry.S:1017 ================================================================================ As ktime_set only judge 'secs' if big than KTIME_SEC_MAX, but if we pass negative value maybe lead to overflow. To address this issue, we must check if 'sec' is negative. Signed-off-by: Ye Bin <yebin10@huawei.com> Link: https://lore.kernel.org/r/20211118015907.844807-1-yebin10@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: fix soft lockup when call __io_remove_buffersYe Bin2021-11-271-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I got issue as follows: [ 567.094140] __io_remove_buffers: [1]start ctx=0xffff8881067bf000 bgid=65533 buf=0xffff8881fefe1680 [ 594.360799] watchdog: BUG: soft lockup - CPU#2 stuck for 26s! [kworker/u32:5:108] [ 594.364987] Modules linked in: [ 594.365405] irq event stamp: 604180238 [ 594.365906] hardirqs last enabled at (604180237): [<ffffffff93fec9bd>] _raw_spin_unlock_irqrestore+0x2d/0x50 [ 594.367181] hardirqs last disabled at (604180238): [<ffffffff93fbbadb>] sysvec_apic_timer_interrupt+0xb/0xc0 [ 594.368420] softirqs last enabled at (569080666): [<ffffffff94200654>] __do_softirq+0x654/0xa9e [ 594.369551] softirqs last disabled at (569080575): [<ffffffff913e1d6a>] irq_exit_rcu+0x1ca/0x250 [ 594.370692] CPU: 2 PID: 108 Comm: kworker/u32:5 Tainted: G L 5.15.0-next-20211112+ #88 [ 594.371891] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014 [ 594.373604] Workqueue: events_unbound io_ring_exit_work [ 594.374303] RIP: 0010:_raw_spin_unlock_irqrestore+0x33/0x50 [ 594.375037] Code: 48 83 c7 18 53 48 89 f3 48 8b 74 24 10 e8 55 f5 55 fd 48 89 ef e8 ed a7 56 fd 80 e7 02 74 06 e8 43 13 7b fd fb bf 01 00 00 00 <e8> f8 78 474 [ 594.377433] RSP: 0018:ffff888101587a70 EFLAGS: 00000202 [ 594.378120] RAX: 0000000024030f0d RBX: 0000000000000246 RCX: 1ffffffff2f09106 [ 594.379053] RDX: 0000000000000000 RSI: ffffffff9449f0e0 RDI: 0000000000000001 [ 594.379991] RBP: ffffffff9586cdc0 R08: 0000000000000001 R09: fffffbfff2effcab [ 594.380923] R10: ffffffff977fe557 R11: fffffbfff2effcaa R12: ffff8881b8f3def0 [ 594.381858] R13: 0000000000000246 R14: ffff888153a8b070 R15: 0000000000000000 [ 594.382787] FS: 0000000000000000(0000) GS:ffff888399c00000(0000) knlGS:0000000000000000 [ 594.383851] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 594.384602] CR2: 00007fcbe71d2000 CR3: 00000000b4216000 CR4: 00000000000006e0 [ 594.385540] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 594.386474] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 594.387403] Call Trace: [ 594.387738] <TASK> [ 594.388042] find_and_remove_object+0x118/0x160 [ 594.389321] delete_object_full+0xc/0x20 [ 594.389852] kfree+0x193/0x470 [ 594.390275] __io_remove_buffers.part.0+0xed/0x147 [ 594.390931] io_ring_ctx_free+0x342/0x6a2 [ 594.392159] io_ring_exit_work+0x41e/0x486 [ 594.396419] process_one_work+0x906/0x15a0 [ 594.399185] worker_thread+0x8b/0xd80 [ 594.400259] kthread+0x3bf/0x4a0 [ 594.401847] ret_from_fork+0x22/0x30 [ 594.402343] </TASK> Message from syslogd@localhost at Nov 13 09:09:54 ... kernel:watchdog: BUG: soft lockup - CPU#2 stuck for 26s! [kworker/u32:5:108] [ 596.793660] __io_remove_buffers: [2099199]start ctx=0xffff8881067bf000 bgid=65533 buf=0xffff8881fefe1680 We can reproduce this issue by follow syzkaller log: r0 = syz_io_uring_setup(0x401, &(0x7f0000000300), &(0x7f0000003000/0x2000)=nil, &(0x7f0000ff8000/0x4000)=nil, &(0x7f0000000280)=<r1=>0x0, &(0x7f0000000380)=<r2=>0x0) sendmsg$ETHTOOL_MSG_FEATURES_SET(0xffffffffffffffff, &(0x7f0000003080)={0x0, 0x0, &(0x7f0000003040)={&(0x7f0000000040)=ANY=[], 0x18}}, 0x0) syz_io_uring_submit(r1, r2, &(0x7f0000000240)=@IORING_OP_PROVIDE_BUFFERS={0x1f, 0x5, 0x0, 0x401, 0x1, 0x0, 0x100, 0x0, 0x1, {0xfffd}}, 0x0) io_uring_enter(r0, 0x3a2d, 0x0, 0x0, 0x0, 0x0) The reason above issue is 'buf->list' has 2,100,000 nodes, occupied cpu lead to soft lockup. To solve this issue, we need add schedule point when do while loop in '__io_remove_buffers'. After add schedule point we do regression, get follow data. [ 240.141864] __io_remove_buffers: [1]start ctx=0xffff888170603000 bgid=65533 buf=0xffff8881116fcb00 [ 268.408260] __io_remove_buffers: [1]start ctx=0xffff8881b92d2000 bgid=65533 buf=0xffff888130c83180 [ 275.899234] __io_remove_buffers: [2099199]start ctx=0xffff888170603000 bgid=65533 buf=0xffff8881116fcb00 [ 296.741404] __io_remove_buffers: [1]start ctx=0xffff8881b659c000 bgid=65533 buf=0xffff8881010fe380 [ 305.090059] __io_remove_buffers: [2099199]start ctx=0xffff8881b92d2000 bgid=65533 buf=0xffff888130c83180 [ 325.415746] __io_remove_buffers: [1]start ctx=0xffff8881b92d1000 bgid=65533 buf=0xffff8881a17d8f00 [ 333.160318] __io_remove_buffers: [2099199]start ctx=0xffff8881b659c000 bgid=65533 buf=0xffff8881010fe380 ... Fixes:8bab4c09f24e("io_uring: allow conditional reschedule for intensive iterators") Signed-off-by: Ye Bin <yebin10@huawei.com> Link: https://lore.kernel.org/r/20211122024737.2198530-1-yebin10@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: fix link traversal lockingPavel Begunkov2021-11-261-18/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | WARNING: inconsistent lock state 5.16.0-rc2-syzkaller #0 Not tainted inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. ffff888078e11418 (&ctx->timeout_lock ){?.+.}-{2:2} , at: io_timeout_fn+0x6f/0x360 fs/io_uring.c:5943 {HARDIRQ-ON-W} state was registered at: [...] spin_unlock_irq include/linux/spinlock.h:399 [inline] __io_poll_remove_one fs/io_uring.c:5669 [inline] __io_poll_remove_one fs/io_uring.c:5654 [inline] io_poll_remove_one+0x236/0x870 fs/io_uring.c:5680 io_poll_remove_all+0x1af/0x235 fs/io_uring.c:5709 io_ring_ctx_wait_and_kill+0x1cc/0x322 fs/io_uring.c:9534 io_uring_release+0x42/0x46 fs/io_uring.c:9554 __fput+0x286/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xc14/0x2b40 kernel/exit.c:832 674ee8e1b4a41 ("io_uring: correct link-list traversal locking") fixed a data race but introduced a possible deadlock and inconsistentcy in irq states. E.g. io_poll_remove_all() spin_lock_irq(timeout_lock) io_poll_remove_one() spin_lock/unlock_irq(poll_lock); spin_unlock_irq(timeout_lock) Another type of problem is freeing a request while holding ->timeout_lock, which may leads to a deadlock in io_commit_cqring() -> io_flush_timeouts() and other places. Having 3 nested locks is also too ugly. Add io_match_task_safe(), which would briefly take and release timeout_lock for race prevention inside, so the actuall request cancellation / free / etc. code doesn't have it taken. Reported-by: syzbot+ff49a3059d49b0ca0eec@syzkaller.appspotmail.com Reported-by: syzbot+847f02ec20a6609a328b@syzkaller.appspotmail.com Reported-by: syzbot+3368aadcd30425ceb53b@syzkaller.appspotmail.com Reported-by: syzbot+51ce8887cdef77c9ac83@syzkaller.appspotmail.com Reported-by: syzbot+3cb756a49d2f394a9ee3@syzkaller.appspotmail.com Fixes: 674ee8e1b4a41 ("io_uring: correct link-list traversal locking") Cc: stable@kernel.org # 5.15+ Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/397f7ebf3f4171f1abe41f708ac1ecb5766f0b68.1637937097.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: fail cancellation for EXITING tasksPavel Begunkov2021-11-261-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | WARNING: CPU: 1 PID: 20 at fs/io_uring.c:6269 io_try_cancel_userdata+0x3c5/0x640 fs/io_uring.c:6269 CPU: 1 PID: 20 Comm: kworker/1:0 Not tainted 5.16.0-rc1-syzkaller #0 Workqueue: events io_fallback_req_func RIP: 0010:io_try_cancel_userdata+0x3c5/0x640 fs/io_uring.c:6269 Call Trace: <TASK> io_req_task_link_timeout+0x6b/0x1e0 fs/io_uring.c:6886 io_fallback_req_func+0xf9/0x1ae fs/io_uring.c:1334 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> We need original task's context to do cancellations, so if it's dying and the callback is executed in a fallback mode, fail the cancellation attempt. Fixes: 89b263f6d56e6 ("io_uring: run linked timeouts from task_work") Cc: stable@kernel.org # 5.15+ Reported-by: syzbot+ab0cfe96c2b3cd1c1153@syzkaller.appspotmail.com Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/4c41c5f379c6941ad5a07cd48cb66ed62199cf7e.1637937097.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: correct link-list traversal lockingPavel Begunkov2021-11-231-4/+8
| | | | | | | | | | | | As io_remove_next_linked() is now under ->timeout_lock (see io_link_timeout_fn), we should update locking around io_for_each_link() and io_match_task() to use the new lock. Cc: stable@kernel.org # 5.15+ Fixes: 89850fce16a1a ("io_uring: run timeouts from task_work") Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/b54541cedf7de59cb5ae36109e58529ca16e66aa.1637631883.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: fix missed comment from *task_file renameKamal Mostafa2021-11-171-1/+1
| | | | | | | | | | Fix comment referring to function "io_uring_del_task_file()", now called "io_uring_del_tctx_node()". Fixes: eef51daa72f7 ("io_uring: rename function *task_file") Signed-off-by: Kamal Mostafa <kamal@canonical.com> Link: https://lore.kernel.org/r/20211116175530.31608-1-kamal@canonical.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: honour zeroes as io-wq worker limitsPavel Begunkov2021-11-081-1/+3
| | | | | | | | | | | | | When we pass in zero as an io-wq worker number limit it shouldn't actually change the limits but return the old value, follow that behaviour with deferred limits setup as well. Cc: stable@kernel.org # 5.15 Reported-by: Beld Zhang <beldzhang@gmail.com> Fixes: e139a1ec92f8d ("io_uring: apply max_workers limit to all future users") Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/1b222a92f7a78a24b042763805e891a4cdd4b544.1636384034.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: remove dead 'sqe' storeJens Axboe2021-11-051-1/+1
| | | | | | | | | The kernel test robot correctly identifies that we store sqe twice, remove the earlier one that is done before validating the index. Fixes: f75d118349be ("io_uring: harder fdinfo sq/cq ring iterating") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: remove redundant assignment to ret in io_register_iowq_max_workers()Nghia Le2021-11-021-1/+0
| | | | | | | | | | | After the assignment, only exit path with label 'err' uses ret as return value. However,before exiting through this path with label 'err', ret is assigned with the return value of io_wq_max_workers(). Hence, the initial assignment is redundant and can be removed. Signed-off-by: Nghia Le <nghialm78@gmail.com> Link: https://lore.kernel.org/r/20211102190521.28291-1-nghialm78@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* io_uring: clean up io_queue_sqe_arm_apollPavel Begunkov2021-11-021-4/+0
| | | | | | | | | | The fix for linked timeout unprep got a bit distored with two rebases, handle linked timeouts for IO_APOLL_READY as with all other cases, i.e. queue it at the end of the function. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/130b1ea5605bbd81d7b874a95332295799d33b81.1635863773.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Merge tag 'selinux-pr-20211101' of ↵Linus Torvalds2021-11-021-8/+63
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: - Add LSM/SELinux/Smack controls and auditing for io-uring. As usual, the individual commit descriptions have more detail, but we were basically missing two things which we're adding here: + establishment of a proper audit context so that auditing of io-uring ops works similarly to how it does for syscalls (with some io-uring additions because io-uring ops are *not* syscalls) + additional LSM hooks to enable access control points for some of the more unusual io-uring features, e.g. credential overrides. The additional audit callouts and LSM hooks were done in conjunction with the io-uring folks, based on conversations and RFC patches earlier in the year. - Fixup the binder credential handling so that the proper credentials are used in the LSM hooks; the commit description and the code comment which is removed in these patches are helpful to understand the background and why this is the proper fix. - Enable SELinux genfscon policy support for securityfs, allowing improved SELinux filesystem labeling for other subsystems which make use of securityfs, e.g. IMA. * tag 'selinux-pr-20211101' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: security: Return xattr name from security_dentry_init_security() selinux: fix a sock regression in selinux_ip_postroute_compat() binder: use cred instead of task for getsecid binder: use cred instead of task for selinux checks binder: use euid from cred instead of using task LSM: Avoid warnings about potentially unused hook variables selinux: fix all of the W=1 build warnings selinux: make better use of the nf_hook_state passed to the NF hooks selinux: fix race condition when computing ocontext SIDs selinux: remove unneeded ipv6 hook wrappers selinux: remove the SELinux lockdown implementation selinux: enable genfscon labeling for securityfs Smack: Brutalist io_uring support selinux: add support for the io_uring access controls lsm,io_uring: add LSM hooks to io_uring io_uring: convert io_uring to the secure anon inode interface fs: add anon_inode_getfile_secure() similar to anon_inode_getfd_secure() audit: add filtering for io_uring records audit,io_uring,io-wq: add some basic audit support to io_uring audit: prepare audit_context for use in calling contexts beyond syscalls
| * lsm,io_uring: add LSM hooks to io_uringPaul Moore2021-09-201-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A full expalantion of io_uring is beyond the scope of this commit description, but in summary it is an asynchronous I/O mechanism which allows for I/O requests and the resulting data to be queued in memory mapped "rings" which are shared between the kernel and userspace. Optionally, io_uring offers the ability for applications to spawn kernel threads to dequeue I/O requests from the ring and submit the requests in the kernel, helping to minimize the syscall overhead. Rings are accessed in userspace by memory mapping a file descriptor provided by the io_uring_setup(2), and can be shared between applications as one might do with any open file descriptor. Finally, process credentials can be registered with a given ring and any process with access to that ring can submit I/O requests using any of the registered credentials. While the io_uring functionality is widely recognized as offering a vastly improved, and high performing asynchronous I/O mechanism, its ability to allow processes to submit I/O requests with credentials other than its own presents a challenge to LSMs. When a process creates a new io_uring ring the ring's credentials are inhertied from the calling process; if this ring is shared with another process operating with different credentials there is the potential to bypass the LSMs security policy. Similarly, registering credentials with a given ring allows any process with access to that ring to submit I/O requests with those credentials. In an effort to allow LSMs to apply security policy to io_uring I/O operations, this patch adds two new LSM hooks. These hooks, in conjunction with the LSM anonymous inode support previously submitted, allow an LSM to apply access control policy to the sharing of io_uring rings as well as any io_uring credential changes requested by a process. The new LSM hooks are described below: * int security_uring_override_creds(cred) Controls if the current task, executing an io_uring operation, is allowed to override it's credentials with @cred. In cases where the current task is a user application, the current credentials will be those of the user application. In cases where the current task is a kernel thread servicing io_uring requests the current credentials will be those of the io_uring ring (inherited from the process that created the ring). * int security_uring_sqpoll(void) Controls if the current task is allowed to create an io_uring polling thread (IORING_SETUP_SQPOLL). Without a SQPOLL thread in the kernel processes must submit I/O requests via io_uring_enter(2) which allows us to compare any requested credential changes against the application making the request. With a SQPOLL thread, we can no longer compare requested credential changes against the application making the request, the comparison is made against the ring's credentials. Signed-off-by: Paul Moore <paul@paul-moore.com>
| * io_uring: convert io_uring to the secure anon inode interfacePaul Moore2021-09-201-2/+2
| | | | | | | | | | | | | | | | | | | | Converting io_uring's anonymous inode to the secure anon inode API enables LSMs to enforce policy on the io_uring anonymous inodes if they chose to do so. This is an important first step towards providing the necessary mechanisms so that LSMs can apply security policy to io_uring operations. Signed-off-by: Paul Moore <paul@paul-moore.com>
| * audit,io_uring,io-wq: add some basic audit support to io_uringPaul Moore2021-09-201-6/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds basic auditing to io_uring operations, regardless of their context. This is accomplished by allocating audit_context structures for the io-wq worker and io_uring SQPOLL kernel threads as well as explicitly auditing the io_uring operations in io_issue_sqe(). Individual io_uring operations can bypass auditing through the "audit_skip" field in the struct io_op_def definition for the operation; although great care must be taken so that security relevant io_uring operations do not bypass auditing; please contact the audit mailing list (see the MAINTAINERS file) with any questions. The io_uring operations are audited using a new AUDIT_URINGOP record, an example is shown below: type=UNKNOWN[1336] msg=audit(1631800225.981:37289): uring_op=19 success=yes exit=0 items=0 ppid=15454 pid=15681 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null) Thanks to Richard Guy Briggs for review and feedback. Signed-off-by: Paul Moore <paul@paul-moore.com>
* | Merge tag 'for-5.16/ki_complete-2021-10-29' of git://git.kernel.dk/linux-blockLinus Torvalds2021-11-011-3/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kiocb->ki_complete() cleanup from Jens Axboe: "This removes the res2 argument from kiocb->ki_complete(). Only the USB gadget code used it, everybody else passes 0. The USB guys checked the user gadget code they could find, and everybody just uses res as expected for the async interface" * tag 'for-5.16/ki_complete-2021-10-29' of git://git.kernel.dk/linux-block: fs: get rid of the res2 iocb->ki_complete argument usb: remove res2 argument from gadget code completions
| * | fs: get rid of the res2 iocb->ki_complete argumentJens Axboe2021-10-251-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The second argument was only used by the USB gadget code, yet everyone pays the overhead of passing a zero to be passed into aio, where it ends up being part of the aio res2 value. Now that everybody is passing in zero, kill off the extra argument. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | Merge tag 'for-5.16/io_uring-2021-10-29' of git://git.kernel.dk/linux-blockLinus Torvalds2021-11-011-825/+889
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring updates from Jens Axboe: "Light on new features - basically just the hybrid mode support. Outside of that it's just fixes, cleanups, and performance improvements. In detail: - Add ring related information to the fdinfo output (Hao) - Hybrid async mode (Hao) - Support for batched issue on block (me) - sqe error trace improvement (me) - IOPOLL efficiency improvements (Pavel) - submit state cleanups and improvements (Pavel) - Completion side improvements (Pavel) - Drain improvements (Pavel) - Buffer selection cleanups (Pavel) - Fixed file node improvements (Pavel) - io-wq setup cancelation fix (Pavel) - Various other performance improvements and cleanups (Pavel) - Misc fixes (Arnd, Bixuan, Changcheng, Hao, me, Noah)" * tag 'for-5.16/io_uring-2021-10-29' of git://git.kernel.dk/linux-block: (97 commits) io-wq: remove worker to owner tw dependency io_uring: harder fdinfo sq/cq ring iterating io_uring: don't assign write hint in the read path io_uring: clusterise ki_flags access in rw_prep io_uring: kill unused param from io_file_supports_nowait io_uring: clean up timeout async_data allocation io_uring: don't try io-wq polling if not supported io_uring: check if opcode needs poll first on arming io_uring: clean iowq submit work cancellation io_uring: clean io_wq_submit_work()'s main loop io-wq: use helper for worker refcounting io_uring: implement async hybrid mode for pollable requests io_uring: Use ERR_CAST() instead of ERR_PTR(PTR_ERR()) io_uring: split logic of force_nonblock io_uring: warning about unused-but-set parameter io_uring: inform block layer of how many requests we are submitting io_uring: simplify io_file_supports_nowait() io_uring: combine REQ_F_NOWAIT_{READ,WRITE} flags io_uring: arm poll for non-nowait files fs/io_uring: Prioritise checking faster conditions first in io_write ...
| * | | io_uring: harder fdinfo sq/cq ring iteratingJens Axboe2021-10-291-22/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ring iteration is racy, which isn't necessarily a problem except it can cause us to iterate the whole thing. That isn't desired or ideal, and it can lead to excessive runtimes of reading fdinfo. Cap the iteration at tail - head OR the ring size. While in there, clean up the ring masking and just dump the raw values along with the masks. That provides more useful debug info. Fixes: 83f84356bc8f ("io_uring: add more uring info to fdinfo for debug") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: don't assign write hint in the read pathJens Axboe2021-10-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Move this out of the generic read/write prep path, and place it in the write specific kiocb setup instead. Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: clusterise ki_flags access in rw_prepPavel Begunkov2021-10-251-10/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ioprio setup doesn't depend on other fields that are modified in io_prep_rw() and we can move it down in the function without worrying about performance. It's useful as it makes iocb->ki_flags accesses/modifications closer together, so it's more likely the compiler will cache it in a register and avoid extra reloads. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/8ee98779c06f1b59f6039b1e292db4332efd664b.1634987320.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: kill unused param from io_file_supports_nowaitPavel Begunkov2021-10-251-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | io_file_supports_nowait() doesn't use rw argument anymore, remove it. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/4bd6709fc573d70c866ea656cb7a7dbe94be8026.1634987320.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: clean up timeout async_data allocationPavel Begunkov2021-10-251-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | opcode prep functions are one of the first things that are called, we can't have ->async_data allocated at this point and it's certainly a bug. Reflect this assumption in io_timeout_prep() and add a WARN_ONCE just in case. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/75a28ca7dbcc5af8b6cd9092819e8384c24dedd4.1634987320.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: don't try io-wq polling if not supportedPavel Begunkov2021-10-251-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If an opcode doesn't support polling, just let it be executed synchronously in iowq, otherwise it will do a nonblock attempt just to fail in io_arm_poll_handler() and return back to blocking execution. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/6401256db01b88f448f15fcd241439cb76f5b940.1634987320.git.asml.silence@gmail.com Reviewed-by: Hao Xu <haoxu@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: check if opcode needs poll first on armingPavel Begunkov2021-10-251-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ->pollout or ->pollin are set only for opcodes that need a file, so if io_arm_poll_handler() tests them first we can be sure that the request has file set and the ->file check can be removed. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/9adfe4f543d984875e516fce6da35348aab48668.1634987320.git.asml.silence@gmail.com Reviewed-by: Hao Xu <haoxu@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: clean iowq submit work cancellationPavel Begunkov2021-10-251-30/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we've got IO_WQ_WORK_CANCEL in io_wq_submit_work(), handle the error on the same lines as the check instead of having a weird code flow. The main loop doesn't change but goes one indention left. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/ff4a09cf41f7a22bbb294b6f1faea721e21fe615.1634987320.git.asml.silence@gmail.com Reviewed-by: Hao Xu <haoxu@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: clean io_wq_submit_work()'s main loopPavel Begunkov2021-10-251-28/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do a bit of cleaning for the main loop of io_wq_submit_work(). Get rid of switch, just replace it with a single if as we're retrying in both other cases. Kill issue_sqe label, Get rid of needs_poll nesting and disambiguate a bit the comment. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/ed12ce0c64e051f9a6b8a37a24f8ea554d299c29.1634987320.git.asml.silence@gmail.com Reviewed-by: Hao Xu <haoxu@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: implement async hybrid mode for pollable requestsHao Xu2021-10-231-1/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current logic of requests with IOSQE_ASYNC is first queueing it to io-worker, then execute it in a synchronous way. For unbound works like pollable requests(e.g. read/write a socketfd), the io-worker may stuck there waiting for events for a long time. And thus other works wait in the list for a long time too. Let's introduce a new way for unbound works (currently pollable requests), with this a request will first be queued to io-worker, then executed in a nonblock try rather than a synchronous way. Failure of that leads it to arm poll stuff and then the worker can begin to handle other works. The detail process of this kind of requests is: step1: original context: queue it to io-worker step2: io-worker context: nonblock try(the old logic is a synchronous try here) | |--fail--> arm poll | |--(fail/ready)-->synchronous issue | |--(succeed)-->worker finish it's job, tw take over the req This works much better than the old IOSQE_ASYNC logic in cases where unbound max_worker is relatively small. In this case, number of io-worker eazily increments to max_worker, new worker cannot be created and running workers stuck there handling old works in IOSQE_ASYNC mode. In my 64-core machine, set unbound max_worker to 20, run echo-server, turns out: (arguments: register_file, connetion number is 1000, message size is 12 Byte) original IOSQE_ASYNC: 76664.151 tps after this patch: 166934.985 tps Suggested-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Link: https://lore.kernel.org/r/20211018133445.103438-1-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: Use ERR_CAST() instead of ERR_PTR(PTR_ERR())Changcheng Deng2021-10-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use ERR_CAST() instead of ERR_PTR(PTR_ERR()). This makes it more readable and also fix this warning detected by err_cast.cocci: ./fs/io_uring.c: WARNING: 3208: 11-18: ERR_CAST can be used with buf Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn> Link: https://lore.kernel.org/r/20211020084948.1038420-1-deng.changcheng@zte.com.cn Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: split logic of force_nonblockHao Xu2021-10-201-22/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently force_nonblock stands for three meanings: - nowait or not - in an io-worker or not(hold uring_lock or not) Let's split the logic to two flags, IO_URING_F_NONBLOCK and IO_URING_F_UNLOCKED for convenience of the next patch. Suggested-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Hao Xu <haoxu@linux.alibaba.com> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/20211018133431.103298-1-haoxu@linux.alibaba.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: warning about unused-but-set parameterArnd Bergmann2021-10-191-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When enabling -Wunused warnings by building with W=1, I get an instance of the -Wunused-but-set-parameter warning in the io_uring code: fs/io_uring.c: In function 'io_queue_async_work': fs/io_uring.c:1445:61: error: parameter 'locked' set but not used [-Werror=unused-but-set-parameter] 1445 | static void io_queue_async_work(struct io_kiocb *req, bool *locked) | ~~~~~~^~~~~~ There are very few warnings of this type, so it would be nice to enable this by default and fix all the existing instances. As the assignment serves no purpose by itself other than to prevent developers from using the variable, an easy workaround is to remove the assignment and just rename the argument to "dont_use". Fixes: f237c30a5610 ("io_uring: batch task work locking") Link: https://lore.kernel.org/lkml/20210920121352.93063-1-arnd@kernel.org/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20211019153507.348480-1-arnd@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: inform block layer of how many requests we are submittingJens Axboe2021-10-191-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The block layer can use this knowledge to make smarter decisions on how to handle the request, if it knows that N more may be coming. Switch to using blk_start_plug_nr_ios() to pass in that information. Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: simplify io_file_supports_nowait()Pavel Begunkov2021-10-191-12/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure that REQ_F_SUPPORT_NOWAIT is always set io_prep_rw(), and so we can stop caring about setting it down the line simplifying io_file_supports_nowait(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/60c8f1f5e2cb45e00f4897b2cec10c5b3669da91.1634425438.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: combine REQ_F_NOWAIT_{READ,WRITE} flagsPavel Begunkov2021-10-191-40/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge REQ_F_NOWAIT_READ and REQ_F_NOWAIT_WRITE into one flag, i.e. REQ_F_SUPPORT_NOWAIT. First it gets rid of dependence on CONFIG_64BIT but also simplifies the code. One thing to consider is when we don't have ->{read,write}_iter and go through loop_rw_iter(). Just fail it with -EAGAIN if we expect nowait behaviour but not sure whether it supports it. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/f832a20e5186c2e79c6519280c238f559a1d2bbc.1634425438.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: arm poll for non-nowait filesPavel Begunkov2021-10-191-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't check if we can do nowait before arming apoll, there are several reasons for that. First, we don't care much about files that don't support nowait. Second, it may be useful -- we don't want to be taking away extra workers from io-wq when it can go in some async. Even if it will go through io-wq eventually, it make difference in the numbers of workers actually used. And the last one, it's needed to clean nowait in future commits. [kernel test robot: fix unused-var] Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/9d06f3cb2c8b686d970269a87986f154edb83043.1634425438.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | fs/io_uring: Prioritise checking faster conditions first in io_writeNoah Goldstein2021-10-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit reorders the conditions in a branch in io_write. The reorder to check 'ret2 == -EAGAIN' first as checking '(req->ctx->flags & IORING_SETUP_IOPOLL)' will likely be more expensive due to 2x memory derefences. Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com> Link: https://lore.kernel.org/r/20211017013229.4124279-1-goldstein.w.n@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: clean io_prep_rw()Pavel Begunkov2021-10-191-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We already store req->file in a variable in io_prep_rw(), just use it instead of a couple of left references to kicob->ki_filp. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/2f5889fc7ab670daefd5ccaedd99416d8355f0ad.1634314022.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: optimise fixed rw rsrc node settingPavel Begunkov2021-10-191-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move fixed rw io_req_set_rsrc_node() from rw prep into io_import_fixed(), if we're using fixed buffers it will always be called during submission as we save the state in advance, Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/68c06f66d5aa9661f1e4b88d08c52d23528297ec.1634314022.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: return iovec from __io_import_iovecPavel Begunkov2021-10-191-22/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We pass iovec** into __io_import_iovec(), which should keep it, initialise and modify accordingly. It's expensive, return it directly from __io_import_iovec encoding errors with ERR_PTR if needed. io_import_iovec keeps the old interface, but it's inline and so everything is optimised nicely. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/6230e9769982f03a8f86fa58df24666088c44d3e.1634314022.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: optimise io_import_iovec fixed pathPavel Begunkov2021-10-191-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Delay loading req->rw.{addr,len} in io_import_iovec until it's really needed, so removing extra loads for the fixed path, which doesn't use them. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/3cc48dd0c4f1a37c4ce9aab5784281a2d83ad8be.1634314022.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: kill io_wq_current_is_worker() in iopollPavel Begunkov2021-10-191-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't decide about locking based on io_wq_current_is_worker(), it's not consistent with all other code and is expensive, use issue_flags. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/7546d5a58efa4360173541c6fe02ee6b8c7b4ea7.1634314022.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: optimise req->ctx reloadsPavel Begunkov2021-10-191-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't load req->ctx in advance, it takes an extra register and the field stays valid even after opcode handlers. It also optimises out req->ctx load in io_iopoll_req_issued() once it's inlined. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/1e45ff671c44be0eb904f2e448a211734893fa0b.1634314022.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: rearrange io_read()/write()Pavel Begunkov2021-10-191-38/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Combine force_nonblock branches (which is already optimised by compiler), flip branches so the most hot/common path is the first, e.g. as with non on-stack iov setup, and add extra likely/unlikely attributions for errror paths. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/2c2536c5896d70994de76e387ea09a0402173a3f.1634144845.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: clean up io_import_iovecPavel Begunkov2021-10-191-15/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make io_import_iovec taking struct io_rw_state instead of an iter pointer. First it takes care of initialising iovec pointer, which can be forgotten. Even more, we can not init it if not needed, e.g. in case of IORING_OP_READ_FIXED or IORING_OP_READ. Also hide saving iter_state inside of it by splitting out an inline function of it to avoid extra ifs. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/b1bbc213a95e5272d4da5867bb977d9acb6f2109.1634144845.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: optimise io_import_iovec nonblock passingPavel Begunkov2021-10-191-22/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | First, change IO_URING_F_NONBLOCK to take sign bit of the int, so checking for it can be turned into test + sign-based-jump, makes the binary smaller and may be faster. Then, instead of passing need_lock boolean into io_import_iovec() just give it issue_flags, which is already stored somewhere. Saves some space on stack, a couple of test + cmov operations and other conversions. note: we still leave force_nonblock = issue_flags & IO_URING_F_NONBLOCK variable, but it's optimised out by the compiler into testing issue_flags directly. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/ee96547e692f6c975c229cd82fc721679571a734.1634144845.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: optimise read/write iov state storingPavel Begunkov2021-10-191-42/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently io_read() and io_write() keep separate pointers to an iter and to struct iov_iter_state, which is not great for register spilling and requires more on-stack copies. They are both either on-stack or in req->async_data at the same time, so use struct io_rw_state and keep a pointer only to it, so having all the state with just one pointer. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/5c5e7ffd7dc25fc35075c70411ba99df72f237fa.1634144845.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: encapsulate rw statePavel Begunkov2021-10-191-19/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new struct io_rw_state storing all iov related bits: fast iov, iterator and iterator state. Not much changes here, simply convert struct io_async_rw to use it. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/e8245ffcb568b228a009ec1eb79c993c813679f1.1634144845.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: optimise rw comletion handlersPavel Begunkov2021-10-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't override req->result in io_complete_rw_iopoll() when it's already of the same value, we have an if just above it, so move the assignment there. Also, add one simle unlikely() in __io_complete_rw_common(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/8dfeb4f84026a20172bcf82c05010abe955874ae.1634144845.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: prioritise read success path over failsPavel Begunkov2021-10-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rearrange io_read return handling so first we expect it completing successfully and only then checking for errors, which is a colder path. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/c91c7c2da11815ec8b04b5d872f60dc4cde662c5.1634144845.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
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