Commit Graph

492 Commits

Author SHA1 Message Date
Pavel Begunkov 7fa8e84192 io_uring/net: rename io_uring_tx_zerocopy_callback
Just a simple renaming patch, io_uring_tx_zerocopy_callback() is too
bulky and doesn't follow usual naming style.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/24d78325403ca6dcb1ec4bced1e33cacc9b832a5.1667557923.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-21 07:38:31 -07:00
Pavel Begunkov fc1dd0d4fa io_uring/net: preset notif tw handler
We're going to have multiple notification tw functions. In preparation
for future changes default the tw callback in advance so later we can
replace it with other versions.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7acdbea5e20eadd844513320cd454af14ba50f64.1667557923.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-21 07:38:31 -07:00
Pavel Begunkov 5bc8e8884b io_uring/net: remove extra notif rsrc setup
io_send_zc_prep() sets up notification's rsrc_node when needed, don't
unconditionally install it on notif alloc.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/dbe4875ac33e180b9799d8537a5e27935e82aac4.1667557923.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-21 07:38:31 -07:00
Pavel Begunkov 3671163beb io_uring: move kbuf put out of generic tw complete
There are multiple users of io_req_task_complete() including zc
notifications, but only read requests use selected buffers. As we
already have an rw specific tw function, move io_put_kbuf() in there.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/94374c7649aaefc3a17808dc4701f25ccd457e25.1667557923.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-21 07:38:31 -07:00
Stefan Metzmacher e307e66981 io_uring/net: introduce IORING_SEND_ZC_REPORT_USAGE flag
It might be useful for applications to detect if a zero copy transfer with
SEND[MSG]_ZC was actually possible or not. The application can fallback to
plain SEND[MSG] in order to avoid the overhead of two cqes per request. Or
it can generate a log message that could indicate to an administrator that
no zero copy was possible and could explain degraded performance.

Cc: stable@vger.kernel.org # 6.1
Link: https://lore.kernel.org/io-uring/fb6a7599-8a9b-15e5-9b64-6cd9d01c6ff4@gmail.com/T/#m2b0d9df94ce43b0e69e6c089bdff0ce6babbdfaa
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8945b01756d902f5d5b0667f20b957ad3f742e5e.1666895626.git.metze@samba.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-21 07:38:31 -07:00
Pavel Begunkov 7fdbc5f014 io_uring: disallow self-propelled ring polling
When we post a CQE we wake all ring pollers as it normally should be.
However, if a CQE was generated by a multishot poll request targeting
its own ring, it'll wake that request up, which will make it to post
a new CQE, which will wake the request and so on until it exhausts all
CQ entries.

Don't allow multishot polling io_uring files but downgrade them to
oneshots, which was always stated as a correct behaviour that the
userspace should check for.

Cc: stable@vger.kernel.org
Fixes: aa43477b04 ("io_uring: poll rework")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3124038c0e7474d427538c2d915335ec28c92d21.1668785722.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-18 09:29:31 -07:00
Pavel Begunkov 100d6b17c0 io_uring: fix multishot recv request leaks
Having REQ_F_POLLED set doesn't guarantee that the request is
executed as a multishot from the polling path. Fortunately for us, if
the code thinks it's multishot issue when it's not, it can only ask to
skip completion so leaking the request. Use issue_flags to mark
multipoll issues.

Cc: stable@vger.kernel.org
Fixes: 1300ebb20286b ("io_uring: multishot recv")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/37762040ba9c52b81b92a2f5ebfd4ee484088951.1668710222.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-17 12:33:33 -07:00
Pavel Begunkov 9148286476 io_uring: fix multishot accept request leaks
Having REQ_F_POLLED set doesn't guarantee that the request is
executed as a multishot from the polling path. Fortunately for us, if
the code thinks it's multishot issue when it's not, it can only ask to
skip completion so leaking the request. Use issue_flags to mark
multipoll issues.

Cc: stable@vger.kernel.org
Fixes: 390ed29b5e ("io_uring: add IORING_ACCEPT_MULTISHOT for accept")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7700ac57653f2823e30b34dc74da68678c0c5f13.1668710222.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-17 12:33:33 -07:00
Pavel Begunkov 539bcb57da io_uring: fix tw losing poll events
We may never try to process a poll wake and its mask if there was
multiple wake ups racing for queueing up a tw. Force
io_poll_check_events() to update the mask by vfs_poll().

Cc: stable@vger.kernel.org
Fixes: aa43477b04 ("io_uring: poll rework")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/00344d60f8b18907171178d7cf598de71d127b0b.1668710222.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-17 12:33:33 -07:00
Pavel Begunkov b98186aee2 io_uring: update res mask in io_poll_check_events
When io_poll_check_events() collides with someone attempting to queue a
task work, it'll spin for one more time. However, it'll continue to use
the mask from the first iteration instead of updating it. For example,
if the first wake up was a EPOLLIN and the second EPOLLOUT, the
userspace will not get EPOLLOUT in time.

Clear the mask for all subsequent iterations to force vfs_poll().

Cc: stable@vger.kernel.org
Fixes: aa43477b04 ("io_uring: poll rework")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/2dac97e8f691231049cb259c4ae57e79e40b537c.1668710222.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-17 12:33:33 -07:00
Pavel Begunkov 12e4e8c7ab io_uring/rw: enable bio caches for IRQ rw
Now we can use IOCB_ALLOC_CACHE not only for iopoll'ed reads/write but
also for normal IRQ driven I/O.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/fb8bd092ed5a4a3b037e84e4777074d07aa5639a.1667384020.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-16 09:44:27 -07:00
Pavel Begunkov 5576035f15 io_uring/poll: lockdep annote io_poll_req_insert_locked
Add a lockdep annotation in io_poll_req_insert_locked().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8115d8e702733754d0aea119e9b5bb63d1eb8b24.1668184658.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-11 09:59:27 -07:00
Pavel Begunkov 30a33669fa io_uring/poll: fix double poll req->flags races
io_poll_double_prepare()            | io_poll_wake()
                                    | poll->head = NULL
smp_load(&poll->head); /* NULL */   |
flags = req->flags;                 |
                                    | req->flags &= ~SINGLE_POLL;
req->flags = flags | DOUBLE_POLL    |

The idea behind io_poll_double_prepare() is to serialise with the
first poll entry by taking the wq lock. However, it's not safe to assume
that io_poll_wake() is not running when we can't grab the lock and so we
may race modifying req->flags.

Skip double poll setup if that happens. It's ok because the first poll
entry will only be removed when it's definitely completing, e.g.
pollfree or oneshot with a valid mask.

Fixes: 49f1c68e04 ("io_uring: optimise submission side poll_refs")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b7fab2d502f6121a7d7b199fe4d914a43ca9cdfd.1668184658.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-11 09:59:27 -07:00
Jens Axboe 3851d25c75 io_uring: check for rollover of buffer ID when providing buffers
We already check if the chosen starting offset for the buffer IDs fit
within an unsigned short, as 65535 is the maximum value for a provided
buffer. But if the caller asks to add N buffers at offset M, and M + N
would exceed the size of the unsigned short, we simply add buffers with
wrapping around the ID.

This is not necessarily a bug and could in fact be a valid use case, but
it seems confusing and inconsistent with the initial check for starting
offset. Let's check for wrap consistently, and error the addition if we
do need to wrap.

Reported-by: Olivier Langlois <olivier@trillion01.com>
Link: https://github.com/axboe/liburing/issues/726
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-10 11:07:41 -07:00
Dylan Yudaken 0fc8c2acbf io_uring: calculate CQEs from the user visible value
io_cqring_wait (and it's wake function io_has_work) used cached_cq_tail in
order to calculate the number of CQEs. cached_cq_tail is set strictly
before the user visible rings->cq.tail

However as far as userspace is concerned,  if io_uring_enter(2) is called
with a minimum number of events, they will verify by checking
rings->cq.tail.

It is therefore possible for io_uring_enter(2) to return early with fewer
events visible to the user.

Instead make the wait functions read from the user visible value, so there
will be no discrepency.

This is triggered eventually by the following reproducer:

struct io_uring_sqe *sqe;
struct io_uring_cqe *cqe;
unsigned int cqe_ready;
struct io_uring ring;
int ret, i;

ret = io_uring_queue_init(N, &ring, 0);
assert(!ret);
while(true) {
	for (i = 0; i < N; i++) {
		sqe = io_uring_get_sqe(&ring);
		io_uring_prep_nop(sqe);
		sqe->flags |= IOSQE_ASYNC;
	}
	ret = io_uring_submit(&ring);
	assert(ret == N);

	do {
		ret = io_uring_wait_cqes(&ring, &cqe, N, NULL, NULL);
	} while(ret == -EINTR);
	cqe_ready = io_uring_cq_ready(&ring);
	assert(!ret);
	assert(cqe_ready == N);
	io_uring_cq_advance(&ring, N);
}

Fixes: ad3eb2c89f ("io_uring: split overflow state into SQ and CQ side")
Signed-off-by: Dylan Yudaken <dylany@meta.com>
Link: https://lore.kernel.org/r/20221108153016.1854297-1-dylany@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-11-08 10:36:15 -07:00
Christian Brauner 5a6f52d20c
acl: conver higher-level helpers to rely on mnt_idmap
Convert an initial portion to rely on struct mnt_idmap by converting the
high level xattr helpers.

Reviewed-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-31 17:48:12 +01:00
Dylan Yudaken b3026767e1 io_uring: unlock if __io_run_local_work locked inside
It is possible for tw to lock the ring, and this was not propogated out to
io_run_local_work. This can cause an unlock to be missed.

Instead pass a pointer to locked into __io_run_local_work.

Fixes: 8ac5d85a89 ("io_uring: add local task_work run helper that is entered locked")
Signed-off-by: Dylan Yudaken <dylany@meta.com>
Link: https://lore.kernel.org/r/20221027144429.3971400-3-dylany@meta.com
[axboe: WARN_ON() -> WARN_ON_ONCE() and add a minor comment]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-27 09:52:12 -06:00
Dylan Yudaken 8de11cdc96 io_uring: use io_run_local_work_locked helper
prefer to use io_run_local_work_locked helper for consistency

Signed-off-by: Dylan Yudaken <dylany@meta.com>
Link: https://lore.kernel.org/r/20221027144429.3971400-2-dylany@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-27 09:51:47 -06:00
Pavel Begunkov cc767e7c69 io_uring/net: fail zc sendmsg when unsupported by socket
The previous patch fails zerocopy send requests for protocols that don't
support it, do the same for zerocopy sendmsg.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0854e7bb4c3d810a48ec8b5853e2f61af36a0467.1666346426.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-22 08:43:03 -06:00
Pavel Begunkov edf8143879 io_uring/net: fail zc send when unsupported by socket
If a protocol doesn't support zerocopy it will silently fall back to
copying. This type of behaviour has always been a source of troubles
so it's better to fail such requests instead.

Cc: <stable@vger.kernel.org> # 6.0
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/2db3c7f16bb6efab4b04569cd16e6242b40c5cb3.1666346426.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-22 08:43:03 -06:00
Rafael Mendonca 996d3efeb0 io-wq: Fix memory leak in worker creation
If the CPU mask allocation for a node fails, then the memory allocated for
the 'io_wqe' struct of the current node doesn't get freed on the error
handling path, since it has not yet been added to the 'wqes' array.

This was spotted when fuzzing v6.1-rc1 with Syzkaller:
BUG: memory leak
unreferenced object 0xffff8880093d5000 (size 1024):
  comm "syz-executor.2", pid 7701, jiffies 4295048595 (age 13.900s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000cb463369>] __kmem_cache_alloc_node+0x18e/0x720
    [<00000000147a3f9c>] kmalloc_node_trace+0x2a/0x130
    [<000000004e107011>] io_wq_create+0x7b9/0xdc0
    [<00000000c38b2018>] io_uring_alloc_task_context+0x31e/0x59d
    [<00000000867399da>] __io_uring_add_tctx_node.cold+0x19/0x1ba
    [<000000007e0e7a79>] io_uring_setup.cold+0x1b80/0x1dce
    [<00000000b545e9f6>] __x64_sys_io_uring_setup+0x5d/0x80
    [<000000008a8a7508>] do_syscall_64+0x5d/0x90
    [<000000004ac08bec>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 0e03496d19 ("io-wq: use private CPU mask")
Cc: stable@vger.kernel.org
Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Link: https://lore.kernel.org/r/20221020014710.902201-1-rafaelmendsr@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-20 05:48:59 -07:00
Harshit Mogalapalli 16bbdfe5fb io_uring/msg_ring: Fix NULL pointer dereference in io_msg_send_fd()
Syzkaller produced the below call trace:

 BUG: KASAN: null-ptr-deref in io_msg_ring+0x3cb/0x9f0
 Write of size 8 at addr 0000000000000070 by task repro/16399

 CPU: 0 PID: 16399 Comm: repro Not tainted 6.1.0-rc1 #28
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7
 Call Trace:
  <TASK>
  dump_stack_lvl+0xcd/0x134
  ? io_msg_ring+0x3cb/0x9f0
  kasan_report+0xbc/0xf0
  ? io_msg_ring+0x3cb/0x9f0
  kasan_check_range+0x140/0x190
  io_msg_ring+0x3cb/0x9f0
  ? io_msg_ring_prep+0x300/0x300
  io_issue_sqe+0x698/0xca0
  io_submit_sqes+0x92f/0x1c30
  __do_sys_io_uring_enter+0xae4/0x24b0
....
 RIP: 0033:0x7f2eaf8f8289
 RSP: 002b:00007fff40939718 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2eaf8f8289
 RDX: 0000000000000000 RSI: 0000000000006f71 RDI: 0000000000000004
 RBP: 00007fff409397a0 R08: 0000000000000000 R09: 0000000000000039
 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004006d0
 R13: 00007fff40939880 R14: 0000000000000000 R15: 0000000000000000
  </TASK>
 Kernel panic - not syncing: panic_on_warn set ...

We don't have a NULL check on file_ptr in io_msg_send_fd() function,
so when file_ptr is NUL src_file is also NULL and get_file()
dereferences a NULL pointer and leads to above crash.

Add a NULL check to fix this issue.

Fixes: e6130eba8a ("io_uring: add support for passing fixed file descriptors")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Link: https://lore.kernel.org/r/20221019171218.1337614-1-harshit.m.mogalapalli@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-19 12:33:33 -07:00
Jens Axboe 5c61795ea9 io_uring/rw: remove leftover debug statement
This debug statement was never meant to go into the upstream release,
kill it off before it ends up in a release. It was just part of the
testing for the initial version of the patch.

Fixes: 2ec33a6c3c ("io_uring/rw: ensure kiocb_end_write() is always called")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-16 17:24:10 -06:00
Pavel Begunkov 02bac94bd8 io_uring: don't iopoll from io_ring_ctx_wait_and_kill()
We should not be completing requests from a task context that has already
undergone io_uring cancellations, i.e. __io_uring_cancel(), as there are
some assumptions, e.g. around cached task refs draining. Remove
iopolling from io_ring_ctx_wait_and_kill() as it can be called later
after PF_EXITING is set with the last task_work run.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7c03cc91455c4a1af49c6b9cbda4e57ea467aa11.1665891182.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-16 17:08:42 -06:00
Pavel Begunkov 34f0bc427e io_uring: reuse io_alloc_req()
Don't duplicate io_alloc_req() in io_req_caches_free() but reuse the
helper.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6005fc88274864a49fc3096c22d8bdd605cf8576.1665891182.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-16 17:08:42 -06:00
Pavel Begunkov 4d5059512d io_uring: kill hot path fixed file bitmap debug checks
We test file_table.bitmap in io_file_get_fixed() to check invariants,
don't do it, it's expensive and was showing up in profiles. No reports of
this triggering has come in. Move the check to the file clear instead,
which will still catch any wrong usage.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/cf77f2ded68d2e5b2bc7355784d969837d48e023.1665891182.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-16 17:07:53 -06:00
Pavel Begunkov 38eddb2c75 io_uring: remove FFS_SCM
THe lifetime of SCM'ed files is bound to ring_sock, which is destroyed
strictly after we're done with registered file tables. This means there
is no need for the FFS_SCM hack, which was not available on 32-bit builds
anyway.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/984226a1045adf42dc35d8bd7fb5a8bbfa472ce1.1665891182.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-16 17:07:12 -06:00
Jens Axboe 2ec33a6c3c io_uring/rw: ensure kiocb_end_write() is always called
A previous commit moved the notifications and end-write handling, but
it is now missing a few spots where we also want to call both of those.
Without that, we can potentially be missing file notifications, and
more importantly, have an imbalance in the super_block writers sem
accounting.

Fixes: b000145e99 ("io_uring/rw: defer fsnotify calls to task context")
Reported-by: Dave Chinner <david@fromorbit.com>
Link: https://lore.kernel.org/all/20221010050319.GC2703033@dread.disaster.area/
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Pavel Begunkov 00927931cb io_uring: fix fdinfo sqe offsets calculation
Only with the big sqe feature they take 128 bytes per entry, but we
unconditionally advance by 128B. Fix it by using sq_shift.

Fixes: 3b8fdd1dc3 ("io_uring/fdinfo: fix sqe dumping for IORING_SETUP_SQE128")
Reported-and-tested-by: syzbot+e5198737e8a2d23d958c@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8b41287cb75d5efb8fcb5cccde845ddbbadd8372.1665449983.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Stefan Roesch c86416c6ff io_uring: local variable rw shadows outer variable in io_write
This fixes the shadowing of the outer variable rw in the function
io_write(). No issue is caused by this, but let's silence the shadowing
warning anyway.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Stefan Roesch <shr@devkernel.io>
Link: https://lore.kernel.org/r/20221010234330.244244-1-shr@devkernel.io
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Jens Axboe 11528491c6 io_uring/opdef: remove 'audit_skip' from SENDMSG_ZC
The msg variants of sending aren't audited separately, so we should not
be setting audit_skip for the zerocopy sendmsg variant either.

Fixes: 493108d95f ("io_uring/net: zerocopy sendmsg")
Reported-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Pavel Begunkov 44f87745d5 io_uring: optimise locking for local tw with submit_wait
Running local task_work requires taking uring_lock, for submit + wait we
can try to run them right after submit while we still hold the lock and
save one lock/unlokc pair. The optimisation was implemented in the first
local tw patches but got dropped for simplicity.

Suggested-by: Dylan Yudaken <dylany@fb.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/281fc79d98b5d91fe4778c5137a17a2ab4693e5c.1665088876.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Pavel Begunkov fc86f9d3bb io_uring: remove redundant memory barrier in io_req_local_work_add
io_cqring_wake() needs a barrier for the waitqueue_active() check.
However, in the case of io_req_local_work_add(), we call llist_add()
first, which implies an atomic. Hence we can replace smb_mb() with
smp_mb__after_atomic().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/43983bc8bc507172adda7a0f00cab1aff09fd238.1665018309.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Jens Axboe 3fb1bd6881 io_uring/net: handle -EINPROGRESS correct for IORING_OP_CONNECT
We treat EINPROGRESS like EAGAIN, but if we're retrying post getting
EINPROGRESS, then we just need to check the socket for errors and
terminate the request.

This was exposed on a bluetooth connection request which ends up
taking a while and hitting EINPROGRESS, and yields a CQE result of
-EBADFD because we're retrying a connect on a socket that is now
connected.

Cc: stable@vger.kernel.org
Fixes: 87f80d623c ("io_uring: handle connect -EINPROGRESS like -EAGAIN")
Link: https://github.com/axboe/liburing/issues/671
Reported-by: Aidan Sun <aidansun05@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Pavel Begunkov b7a817752e io_uring: remove notif leftovers
Notifications were killed but there is a couple of fields and struct
declarations left, remove them.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8df8877d677be5a2b43afd936d600e60105ea960.1664849941.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Pavel Begunkov 42b6419d0a io_uring: correct pinned_vm accounting
->mm_account should be released only after we free all registered
buffers, otherwise __io_sqe_buffers_unregister() will see a NULL
->mm_account and skip locked_vm accounting.

Cc: <Stable@vger.kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6d798f65ed4ab8db3664c4d3397d4af16ca98846.1664849932.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:56 -06:00
Pavel Begunkov 0091bfc817 io_uring/af_unix: defer registered files gc to io_uring release
Instead of putting io_uring's registered files in unix_gc() we want it
to be done by io_uring itself. The trick here is to consider io_uring
registered files for cycle detection but not actually putting them down.
Because io_uring can't register other ring instances, this will remove
all refs to the ring file triggering the ->release path and clean up
with io_ring_ctx_free().

Cc: stable@vger.kernel.org
Fixes: 6b06314c47 ("io_uring: add file set registration")
Reported-and-tested-by: David Bouman <dbouman03@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
[axboe: add kerneldoc comment to skb, fold in skb leak fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-12 16:30:34 -06:00
Pavel Begunkov d7cce96c44 io_uring: limit registration w/ SINGLE_ISSUER
IORING_SETUP_SINGLE_ISSUER restricts what tasks can submit requests.
Extend it to registration as well, so non-owning task can't do
registrations. It's not necessary at the moment but might be useful in
the future.

Cc: <stable@vger.kernel.org> # 6.0
Fixes: 97bbdc06a4 ("io_uring: add IORING_SETUP_SINGLE_ISSUER")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f52a6a9c8a8990d4a831f73c0571e7406aac2bba.1664237592.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-07 12:25:30 -06:00
Dylan Yudaken 4add705e4e io_uring: remove io_register_submitter
this is no longer needed, as submitter_task is set at creation time.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Fixes: 97bbdc06a4 ("io_uring: add IORING_SETUP_SINGLE_ISSUER")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-07 12:25:30 -06:00
Dylan Yudaken 97c96e9fa3 io_uring: simplify __io_uring_add_tctx_node
Remove submitter parameter from __io_uring_add_tctx_node.

It was only called from one place, and we can do that logic in that one
place.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Fixes: 97bbdc06a4 ("io_uring: add IORING_SETUP_SINGLE_ISSUER")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-07 12:25:30 -06:00
Linus Torvalds 7c989b1da3 for-6.1/passthrough-2022-10-04
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Merge tag 'for-6.1/passthrough-2022-10-04' of git://git.kernel.dk/linux

Pull passthrough updates from Jens Axboe:
 "With these changes, passthrough NVMe support over io_uring now
  performs at the same level as block device O_DIRECT, and in many cases
  6-8% better.

  This contains:

   - Add support for fixed buffers for passthrough (Anuj, Kanchan)

   - Enable batched allocations and freeing on passthrough, similarly to
     what we support on the normal storage path (me)

   - Fix from Geert fixing an issue with !CONFIG_IO_URING"

* tag 'for-6.1/passthrough-2022-10-04' of git://git.kernel.dk/linux:
  io_uring: Add missing inline to io_uring_cmd_import_fixed() dummy
  nvme: wire up fixed buffer support for nvme passthrough
  nvme: pass ubuffer as an integer
  block: extend functionality to map bvec iterator
  block: factor out blk_rq_map_bio_alloc helper
  block: rename bio_map_put to blk_mq_map_bio_put
  nvme: refactor nvme_alloc_request
  nvme: refactor nvme_add_user_metadata
  nvme: Use blk_rq_map_user_io helper
  scsi: Use blk_rq_map_user_io helper
  block: add blk_rq_map_user_io
  io_uring: introduce fixed buffer support for io_uring_cmd
  io_uring: add io_uring_cmd_import_fixed
  nvme: enable batched completions of passthrough IO
  nvme: split out metadata vs non metadata end_io uring_cmd completions
  block: allow end_io based requests in the completion batch handling
  block: change request end_io handler to pass back a return value
  block: enable batched allocation for blk_mq_alloc_request()
  block: kill deprecated BUG_ON() in the flush handling
2022-10-07 09:35:50 -07:00
Linus Torvalds 513389809e for-6.1/block-2022-10-03
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Merge tag 'for-6.1/block-2022-10-03' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - NVMe pull requests via Christoph:
      - handle number of queue changes in the TCP and RDMA drivers
        (Daniel Wagner)
      - allow changing the number of queues in nvmet (Daniel Wagner)
      - also consider host_iface when checking ip options (Daniel
        Wagner)
      - don't map pages which can't come from HIGHMEM (Fabio M. De
        Francesco)
      - avoid unnecessary flush bios in nvmet (Guixin Liu)
      - shrink and better pack the nvme_iod structure (Keith Busch)
      - add comment for unaligned "fake" nqn (Linjun Bao)
      - print actual source IP address through sysfs "address" attr
        (Martin Belanger)
      - various cleanups (Jackie Liu, Wolfram Sang, Genjian Zhang)
      - handle effects after freeing the request (Keith Busch)
      - copy firmware_rev on each init (Keith Busch)
      - restrict management ioctls to admin (Keith Busch)
      - ensure subsystem reset is single threaded (Keith Busch)
      - report the actual number of tagset maps in nvme-pci (Keith
        Busch)
      - small fabrics authentication fixups (Christoph Hellwig)
      - add common code for tagset allocation and freeing (Christoph
        Hellwig)
      - stop using the request_queue in nvmet (Christoph Hellwig)
      - set min_align_mask before calculating max_hw_sectors (Rishabh
        Bhatnagar)
      - send a rediscover uevent when a persistent discovery controller
        reconnects (Sagi Grimberg)
      - misc nvmet-tcp fixes (Varun Prakash, zhenwei pi)

 - MD pull request via Song:
      - Various raid5 fix and clean up, by Logan Gunthorpe and David
        Sloan.
      - Raid10 performance optimization, by Yu Kuai.

 - sbitmap wakeup hang fixes (Hugh, Keith, Jan, Yu)

 - IO scheduler switching quisce fix (Keith)

 - s390/dasd block driver updates (Stefan)

 - support for recovery for the ublk driver (ZiyangZhang)

 - rnbd drivers fixes and updates (Guoqing, Santosh, ye, Christoph)

 - blk-mq and null_blk map fixes (Bart)

 - various bcache fixes (Coly, Jilin, Jules)

 - nbd signal hang fix (Shigeru)

 - block writeback throttling fix (Yu)

 - optimize the passthrough mapping handling (me)

 - prepare block cgroups to being gendisk based (Christoph)

 - get rid of an old PSI hack in the block layer, moving it to the
   callers instead where it belongs (Christoph)

 - blk-throttle fixes and cleanups (Yu)

 - misc fixes and cleanups (Liu Shixin, Liu Song, Miaohe, Pankaj,
   Ping-Xiang, Wolfram, Saurabh, Li Jinlin, Li Lei, Lin, Li zeming,
   Miaohe, Bart, Coly, Gaosheng

* tag 'for-6.1/block-2022-10-03' of git://git.kernel.dk/linux: (162 commits)
  sbitmap: fix lockup while swapping
  block: add rationale for not using blk_mq_plug() when applicable
  block: adapt blk_mq_plug() to not plug for writes that require a zone lock
  s390/dasd: use blk_mq_alloc_disk
  blk-cgroup: don't update the blkg lookup hint in blkg_conf_prep
  nvmet: don't look at the request_queue in nvmet_bdev_set_limits
  nvmet: don't look at the request_queue in nvmet_bdev_zone_mgmt_emulate_all
  blk-mq: use quiesced elevator switch when reinitializing queues
  block: replace blk_queue_nowait with bdev_nowait
  nvme: remove nvme_ctrl_init_connect_q
  nvme-loop: use the tagset alloc/free helpers
  nvme-loop: store the generic nvme_ctrl in set->driver_data
  nvme-loop: initialize sqsize later
  nvme-fc: use the tagset alloc/free helpers
  nvme-fc: store the generic nvme_ctrl in set->driver_data
  nvme-fc: keep ctrl->sqsize in sync with opts->queue_size
  nvme-rdma: use the tagset alloc/free helpers
  nvme-rdma: store the generic nvme_ctrl in set->driver_data
  nvme-tcp: use the tagset alloc/free helpers
  nvme-tcp: store the generic nvme_ctrl in set->driver_data
  ...
2022-10-07 09:19:14 -07:00
Linus Torvalds 0a78a376ef for-6.1/io_uring-2022-10-03
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Merge tag 'for-6.1/io_uring-2022-10-03' of git://git.kernel.dk/linux

Pull io_uring updates from Jens Axboe:

 - Add supported for more directly managed task_work running.

   This is beneficial for real world applications that end up issuing
   lots of system calls as part of handling work. Normal task_work will
   always execute as we transition in and out of the kernel, even for
   "unrelated" system calls. It's more efficient to defer the handling
   of io_uring's deferred work until the application wants it to be run,
   generally in batches.

   As part of ongoing work to write an io_uring network backend for
   Thrift, this has been shown to greatly improve performance. (Dylan)

 - Add IOPOLL support for passthrough (Kanchan)

 - Improvements and fixes to the send zero-copy support (Pavel)

 - Partial IO handling fixes (Pavel)

 - CQE ordering fixes around CQ ring overflow (Pavel)

 - Support sendto() for non-zc as well (Pavel)

 - Support sendmsg for zerocopy (Pavel)

 - Networking iov_iter fix (Stefan)

 - Misc fixes and cleanups (Pavel, me)

* tag 'for-6.1/io_uring-2022-10-03' of git://git.kernel.dk/linux: (56 commits)
  io_uring/net: fix notif cqe reordering
  io_uring/net: don't update msg_name if not provided
  io_uring: don't gate task_work run on TIF_NOTIFY_SIGNAL
  io_uring/rw: defer fsnotify calls to task context
  io_uring/net: fix fast_iov assignment in io_setup_async_msg()
  io_uring/net: fix non-zc send with address
  io_uring/net: don't skip notifs for failed requests
  io_uring/rw: don't lose short results on io_setup_async_rw()
  io_uring/rw: fix unexpected link breakage
  io_uring/net: fix cleanup double free free_iov init
  io_uring: fix CQE reordering
  io_uring/net: fix UAF in io_sendrecv_fail()
  selftest/net: adjust io_uring sendzc notif handling
  io_uring: ensure local task_work marks task as running
  io_uring/net: zerocopy sendmsg
  io_uring/net: combine fail handlers
  io_uring/net: rename io_sendzc()
  io_uring/net: support non-zerocopy sendto
  io_uring/net: refactor io_setup_async_addr
  io_uring/net: don't lose partial send_zc on fail
  ...
2022-10-07 08:52:43 -07:00
Linus Torvalds 4c0ed7d8d6 whack-a-mole: constifying struct path *
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Merge tag 'pull-path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs constification updates from Al Viro:
 "whack-a-mole: constifying struct path *"

* tag 'pull-path' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ecryptfs: constify path
  spufs: constify path
  nd_jump_link(): constify path
  audit_init_parent(): constify path
  __io_setxattr(): constify path
  do_proc_readlink(): constify path
  overlayfs: constify path
  fs/notify: constify path
  may_linkat(): constify path
  do_sys_name_to_handle(): constify path
  ->getprocattr(): attribute name is const char *, TYVM...
2022-10-06 17:31:02 -07:00
Linus Torvalds a0debc4c7a io_uring-6.0-2022-09-29
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Merge tag 'io_uring-6.0-2022-09-29' of git://git.kernel.dk/linux

Pull io_uring fixes from Jens Axboe:
 "Two fixes that should go into 6.0:

   - Tweak the single issuer logic to register the task at creation,
     rather than at first submit. SINGLE_ISSUER was added for 6.0, and
     after some discussion on this, we decided to make it a bit stricter
     while it's still possible to do so (Dylan).

   - Stefan from Samba had some doubts on the level triggered poll that
     was added for this release. Rather than attempt to mess around with
     it now, just do the quick one-liner to disable it for release and
     we have time to discuss and change it for 6.1 instead (me)"

* tag 'io_uring-6.0-2022-09-29' of git://git.kernel.dk/linux:
  io_uring/poll: disable level triggered poll
  io_uring: register single issuer task at creation
2022-09-30 09:28:39 -07:00
Anuj Gupta 9cda70f622 io_uring: introduce fixed buffer support for io_uring_cmd
Add IORING_URING_CMD_FIXED flag that is to be used for sending io_uring
command with previously registered buffers. User-space passes the buffer
index in sqe->buf_index, same as done in read/write variants that uses
fixed buffers.

Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20220930062749.152261-3-anuj20.g@samsung.com
[axboe: shuffle valid flags check before acting on it]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-30 07:50:59 -06:00
Anuj Gupta a9216fac3e io_uring: add io_uring_cmd_import_fixed
This is a new helper that callers can use to obtain a bvec iterator for
the previously mapped buffer. This is preparatory work to enable
fixed-buffer support for io_uring_cmd.

Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20220930062749.152261-2-anuj20.g@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-30 07:49:11 -06:00
Jens Axboe 5853a7b551 Merge branch 'for-6.1/io_uring' into for-6.1/passthrough
* for-6.1/io_uring: (56 commits)
  io_uring/net: fix notif cqe reordering
  io_uring/net: don't update msg_name if not provided
  io_uring: don't gate task_work run on TIF_NOTIFY_SIGNAL
  io_uring/rw: defer fsnotify calls to task context
  io_uring/net: fix fast_iov assignment in io_setup_async_msg()
  io_uring/net: fix non-zc send with address
  io_uring/net: don't skip notifs for failed requests
  io_uring/rw: don't lose short results on io_setup_async_rw()
  io_uring/rw: fix unexpected link breakage
  io_uring/net: fix cleanup double free free_iov init
  io_uring: fix CQE reordering
  io_uring/net: fix UAF in io_sendrecv_fail()
  selftest/net: adjust io_uring sendzc notif handling
  io_uring: ensure local task_work marks task as running
  io_uring/net: zerocopy sendmsg
  io_uring/net: combine fail handlers
  io_uring/net: rename io_sendzc()
  io_uring/net: support non-zerocopy sendto
  io_uring/net: refactor io_setup_async_addr
  io_uring/net: don't lose partial send_zc on fail
  ...
2022-09-30 07:47:42 -06:00
Jens Axboe 736feaa3a0 Merge branch 'for-6.1/block' into for-6.1/passthrough
* for-6.1/block: (162 commits)
  sbitmap: fix lockup while swapping
  block: add rationale for not using blk_mq_plug() when applicable
  block: adapt blk_mq_plug() to not plug for writes that require a zone lock
  s390/dasd: use blk_mq_alloc_disk
  blk-cgroup: don't update the blkg lookup hint in blkg_conf_prep
  nvmet: don't look at the request_queue in nvmet_bdev_set_limits
  nvmet: don't look at the request_queue in nvmet_bdev_zone_mgmt_emulate_all
  blk-mq: use quiesced elevator switch when reinitializing queues
  block: replace blk_queue_nowait with bdev_nowait
  nvme: remove nvme_ctrl_init_connect_q
  nvme-loop: use the tagset alloc/free helpers
  nvme-loop: store the generic nvme_ctrl in set->driver_data
  nvme-loop: initialize sqsize later
  nvme-fc: use the tagset alloc/free helpers
  nvme-fc: store the generic nvme_ctrl in set->driver_data
  nvme-fc: keep ctrl->sqsize in sync with opts->queue_size
  nvme-rdma: use the tagset alloc/free helpers
  nvme-rdma: store the generic nvme_ctrl in set->driver_data
  nvme-tcp: use the tagset alloc/free helpers
  nvme-tcp: store the generic nvme_ctrl in set->driver_data
  ...

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-30 07:47:38 -06:00
Pavel Begunkov 108893ddcc io_uring/net: fix notif cqe reordering
send zc is not restricted to !IO_URING_F_UNLOCKED anymore and so
we can't use task-tw ordering trick to order notification cqes
with requests completions. In this case leave it alone and let
io_send_zc_cleanup() flush it.

Cc: stable@vger.kernel.org
Fixes: 53bdc88aac ("io_uring/notif: order notif vs send CQEs")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0031f3a00d492e814a4a0935a2029a46d9c9ba06.1664486545.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-29 17:46:04 -06:00
Pavel Begunkov 6f10ae8a15 io_uring/net: don't update msg_name if not provided
io_sendmsg_copy_hdr() may clear msg->msg_name if the userspace didn't
provide it, we should retain NULL in this case.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/97d49f61b5ec76d0900df658cfde3aa59ff22121.1664486545.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-29 17:46:04 -06:00
Jens Axboe 46a525e199 io_uring: don't gate task_work run on TIF_NOTIFY_SIGNAL
This isn't a reliable mechanism to tell if we have task_work pending, we
really should be looking at whether we have any items queued. This is
problematic if forward progress is gated on running said task_work. One
such example is reading from a pipe, where the write side has been closed
right before the read is started. The fput() of the file queues TWA_RESUME
task_work, and we need that task_work to be run before ->release() is
called for the pipe. If ->release() isn't called, then the read will sit
forever waiting on data that will never arise.

Fix this by io_run_task_work() so it checks if we have task_work pending
rather than rely on TIF_NOTIFY_SIGNAL for that. The latter obviously
doesn't work for task_work that is queued without TWA_SIGNAL.

Reported-by: Christiano Haesbaert <haesbaert@haesbaert.org>
Cc: stable@vger.kernel.org
Link: https://github.com/axboe/liburing/issues/665
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-29 16:07:45 -06:00
Jens Axboe b000145e99 io_uring/rw: defer fsnotify calls to task context
We can't call these off the kiocb completion as that might be off
soft/hard irq context. Defer the calls to when we process the
task_work for this request. That avoids valid complaints like:

stack backtrace:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.0.0-rc6-syzkaller-00321-g105a36f3694e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_usage_bug kernel/locking/lockdep.c:3961 [inline]
 valid_state kernel/locking/lockdep.c:3973 [inline]
 mark_lock_irq kernel/locking/lockdep.c:4176 [inline]
 mark_lock.part.0.cold+0x18/0xd8 kernel/locking/lockdep.c:4632
 mark_lock kernel/locking/lockdep.c:4596 [inline]
 mark_usage kernel/locking/lockdep.c:4527 [inline]
 __lock_acquire+0x11d9/0x56d0 kernel/locking/lockdep.c:5007
 lock_acquire kernel/locking/lockdep.c:5666 [inline]
 lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631
 __fs_reclaim_acquire mm/page_alloc.c:4674 [inline]
 fs_reclaim_acquire+0x115/0x160 mm/page_alloc.c:4688
 might_alloc include/linux/sched/mm.h:271 [inline]
 slab_pre_alloc_hook mm/slab.h:700 [inline]
 slab_alloc mm/slab.c:3278 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3471 [inline]
 kmem_cache_alloc+0x39/0x520 mm/slab.c:3491
 fanotify_alloc_fid_event fs/notify/fanotify/fanotify.c:580 [inline]
 fanotify_alloc_event fs/notify/fanotify/fanotify.c:813 [inline]
 fanotify_handle_event+0x1130/0x3f40 fs/notify/fanotify/fanotify.c:948
 send_to_group fs/notify/fsnotify.c:360 [inline]
 fsnotify+0xafb/0x1680 fs/notify/fsnotify.c:570
 __fsnotify_parent+0x62f/0xa60 fs/notify/fsnotify.c:230
 fsnotify_parent include/linux/fsnotify.h:77 [inline]
 fsnotify_file include/linux/fsnotify.h:99 [inline]
 fsnotify_access include/linux/fsnotify.h:309 [inline]
 __io_complete_rw_common+0x485/0x720 io_uring/rw.c:195
 io_complete_rw+0x1a/0x1f0 io_uring/rw.c:228
 iomap_dio_complete_work fs/iomap/direct-io.c:144 [inline]
 iomap_dio_bio_end_io+0x438/0x5e0 fs/iomap/direct-io.c:178
 bio_endio+0x5f9/0x780 block/bio.c:1564
 req_bio_endio block/blk-mq.c:695 [inline]
 blk_update_request+0x3fc/0x1300 block/blk-mq.c:825
 scsi_end_request+0x7a/0x9a0 drivers/scsi/scsi_lib.c:541
 scsi_io_completion+0x173/0x1f70 drivers/scsi/scsi_lib.c:971
 scsi_complete+0x122/0x3b0 drivers/scsi/scsi_lib.c:1438
 blk_complete_reqs+0xad/0xe0 block/blk-mq.c:1022
 __do_softirq+0x1d3/0x9c6 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
 common_interrupt+0xa9/0xc0 arch/x86/kernel/irq.c:240

Fixes: f63cf5192f ("io_uring: ensure that fsnotify is always called")
Link: https://lore.kernel.org/all/20220929135627.ykivmdks2w5vzrwg@quack3/
Reported-by: syzbot+dfcc5f4da15868df7d4d@syzkaller.appspotmail.com
Reported-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-29 11:00:41 -06:00
Stefan Metzmacher 3e4cb6ebbb io_uring/net: fix fast_iov assignment in io_setup_async_msg()
I hit a very bad problem during my tests of SENDMSG_ZC.
BUG(); in first_iovec_segment() triggered very easily.
The problem was io_setup_async_msg() in the partial retry case,
which seems to happen more often with _ZC.

iov_iter_iovec_advance() may change i->iov in order to have i->iov_offset
being only relative to the first element.

Which means kmsg->msg.msg_iter.iov is no longer the
same as kmsg->fast_iov.

But this would rewind the copy to be the start of
async_msg->fast_iov, which means the internal
state of sync_msg->msg.msg_iter is inconsitent.

I tested with 5 vectors with length like this 4, 0, 64, 20, 8388608
and got a short writes with:
- ret=2675244 min_ret=8388692 => remaining 5713448 sr->done_io=2675244
- ret=-EAGAIN => io_uring_poll_arm
- ret=4911225 min_ret=5713448 => remaining 802223  sr->done_io=7586469
- ret=-EAGAIN => io_uring_poll_arm
- ret=802223  min_ret=802223  => res=8388692

While this was easily triggered with SENDMSG_ZC (queued for 6.1),
it was a potential problem starting with 7ba89d2af1
in 5.18 for IORING_OP_RECVMSG.
And also with 4c3c09439c in 5.19
for IORING_OP_SENDMSG.

However 257e84a537 introduced the critical
code into io_setup_async_msg() in 5.11.

Fixes: 7ba89d2af1 ("io_uring: ensure recv and recvmsg handle MSG_WAITALL correctly")
Fixes: 257e84a537 ("io_uring: refactor sendmsg/recvmsg iov managing")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b2e7be246e2fb173520862b0c7098e55767567a2.1664436949.git.metze@samba.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-29 07:08:21 -06:00
Pavel Begunkov 04360d3e05 io_uring/net: fix non-zc send with address
We're currently ignoring the dest address with non-zerocopy send because
even though we copy it from the userspace shortly after ->msg_name gets
zeroed. Move msghdr init earlier.

Fixes: 516e82f0e0 ("io_uring/net: support non-zerocopy sendto")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/176ced5e8568aa5d300ca899b7f05b303ebc49fd.1664409532.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-28 19:29:12 -06:00
Jens Axboe d59bd748db io_uring/poll: disable level triggered poll
Stefan reports that there are issues with the level triggered
notification. Since we're late in the cycle, and it was introduced for
the 6.0 release, just disable it at prep time and we can bring this
back when Samba is happy with it.

Reported-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-28 19:27:11 -06:00
Pavel Begunkov 6ae91ac9a6 io_uring/net: don't skip notifs for failed requests
We currently only add a notification CQE when the send succeded, i.e.
cqe.res >= 0. However, it'd be more robust to do buffer notifications
for failed requests as well in case drivers decide do something fanky.

Always return a buffer notification after initial prep, don't hide it.
This behaviour is better aligned with documentation and the patch also
helps the userspace to respect it.

Cc: stable@vger.kernel.org # 6.0
Suggested-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9c8bead87b2b980fcec441b8faef52188b4a6588.1664292100.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-28 07:53:15 -06:00
Christoph Hellwig 568ec936bf block: replace blk_queue_nowait with bdev_nowait
Replace blk_queue_nowait with a bdev_nowait helpers that takes the
block_device given that the I/O submission path should not have to
look into the request_queue.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Link: https://lore.kernel.org/r/20220927075815.269694-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27 09:57:58 -06:00
Pavel Begunkov c278d9f8ac io_uring/rw: don't lose short results on io_setup_async_rw()
If a retry io_setup_async_rw() fails we lose result from the first
io_iter_do_read(), which is a problem mostly for streams/sockets.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0e8d20cebe5fc9c96ed268463c394237daabc384.1664235732.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-26 18:44:15 -06:00
Pavel Begunkov bf68b5b343 io_uring/rw: fix unexpected link breakage
req->cqe.res is set in io_read() to the amount of bytes left to be done,
which is used to figure out whether to fail a read or not. However,
io_read() may do another without returning, and we stash the previous
value into ->bytes_done but forget to update cqe.res. Then we ask a read
to do strictly less than cqe.res but expect the return to be exactly
cqe.res.

Fix the bug by updating cqe.res for retries.

Cc: stable@vger.kernel.org
Reported-and-Tested-by: Beld Zhang <beldzhang@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3a1088440c7be98e5800267af922a67da0ef9f13.1664235732.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-26 18:44:15 -06:00
Dylan Yudaken 7cae596bc3 io_uring: register single issuer task at creation
Instead of picking the task from the first submitter task, rather use the
creator task or in the case of disabled (IORING_SETUP_R_DISABLED) the
enabling task.

This approach allows a lot of simplification of the logic here. This
removes init logic from the submission path, which can always be a bit
confusing, but also removes the need for locking to write (or read) the
submitter_task.

Users that want to move a ring before submitting can create the ring
disabled and then enable it on the submitting task.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Fixes: 97bbdc06a4 ("io_uring: add IORING_SETUP_SINGLE_ISSUER")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-26 11:26:18 -06:00
Pavel Begunkov 4c17a496a7 io_uring/net: fix cleanup double free free_iov init
Having ->async_data doesn't mean it's initialised and previously we vere
relying on setting F_CLEANUP at the right moment. With zc sendmsg
though, we set F_CLEANUP early in prep when we alloc a notif and so we
may allocate async_data, fail in copy_msg_hdr() leaving
struct io_async_msghdr not initialised correctly but with F_CLEANUP
set, which causes a ->free_iov double free and probably other nastiness.

Always initialise ->free_iov. Also, now it might point to fast_iov when
fails, so avoid freeing it during cleanups.

Reported-by: syzbot+edfd15cd4246a3fc615a@syzkaller.appspotmail.com
Fixes: 493108d95f ("io_uring/net: zerocopy sendmsg")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-26 08:36:50 -06:00
Linus Torvalds 3db61221f4 io_uring-6.0-2022-09-23
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Merge tag 'io_uring-6.0-2022-09-23' of git://git.kernel.dk/linux

Pull io_uring fix from Jens Axboe:
 "Just a single fix for an issue with un-reaped IOPOLL requests on ring
  exit"

* tag 'io_uring-6.0-2022-09-23' of git://git.kernel.dk/linux:
  io_uring: ensure that cached task references are always put on exit
2022-09-24 08:27:08 -07:00
Jens Axboe e775f93f2a io_uring: ensure that cached task references are always put on exit
io_uring caches task references to avoid doing atomics for each of them
per request. If a request is put from the same task that allocated it,
then we can maintain a per-ctx cache of them. This obviously relies
on io_uring always pruning caches in a reliable way, and there's
currently a case off io_uring fd release where we can miss that.

One example is a ring setup with IOPOLL, which relies on the task
polling for completions, which will free them. However, if such a task
submits a request and then exits or closes the ring without reaping
the completion, then ring release will reap and put. If release happens
from that very same task, the completed request task refs will get
put back into the cache pool. This is problematic, as we're now beyond
the point of pruning caches.

Manually drop these caches after doing an IOPOLL reap. This releases
references from the current task, which is enough. If another task
happens to be doing the release, then the caching will not be
triggered and there's no issue.

Cc: stable@vger.kernel.org
Fixes: e98e49b2bb ("io_uring: extend task put optimisations")
Reported-by: Homin Rhee <hominlab@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-23 18:51:08 -06:00
Pavel Begunkov aa1df3a360 io_uring: fix CQE reordering
Overflowing CQEs may result in reordering, which is buggy in case of
links, F_MORE and so on. If we guarantee that we don't reorder for
the unlikely event of a CQ ring overflow, then we can further extend
this to not have to terminate multishot requests if it happens. For
other operations, like zerocopy sends, we have no choice but to honor
CQE ordering.

Reported-by: Dylan Yudaken <dylany@fb.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/ec3bc55687b0768bbe20fb62d7d06cfced7d7e70.1663892031.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-23 15:04:20 -06:00
Pavel Begunkov a75155faef io_uring/net: fix UAF in io_sendrecv_fail()
We should not assume anything about ->free_iov just from
REQ_F_ASYNC_DATA but rather rely on REQ_F_NEED_CLEANUP, as we may
allocate ->async_data but failed init would leave the field in not
consistent state. The easiest solution is to remove removing
REQ_F_NEED_CLEANUP and so ->async_data dealloc from io_sendrecv_fail()
and let io_send_zc_cleanup() do the job. The catch here is that we also
need to prevent double notif flushing, just test it for NULL and zero
where it's needed.

BUG: KASAN: use-after-free in io_sendrecv_fail+0x3b0/0x3e0 io_uring/net.c:1221
Write of size 8 at addr ffff8880771b4080 by task syz-executor.3/30199

CPU: 1 PID: 30199 Comm: syz-executor.3 Not tainted 6.0.0-rc6-next-20220923-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15e/0x45d mm/kasan/report.c:395
 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495
 io_sendrecv_fail+0x3b0/0x3e0 io_uring/net.c:1221
 io_req_complete_failed+0x155/0x1b0 io_uring/io_uring.c:873
 io_drain_req io_uring/io_uring.c:1648 [inline]
 io_queue_sqe_fallback.cold+0x29f/0x788 io_uring/io_uring.c:1931
 io_submit_sqe io_uring/io_uring.c:2160 [inline]
 io_submit_sqes+0x1180/0x1df0 io_uring/io_uring.c:2276
 __do_sys_io_uring_enter+0xac6/0x2410 io_uring/io_uring.c:3216
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: c4c0009e0b ("io_uring/net: combine fail handlers")
Reported-by: syzbot+4c597a574a3f5a251bda@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/23ab8346e407ea50b1198a172c8a97e1cf22915b.1663945875.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-23 14:57:38 -06:00
Jens Axboe ec7fd2562f io_uring: ensure local task_work marks task as running
io_uring will run task_work from contexts that have been prepared for
waiting, and in doing so it'll implicitly set the task running again
to avoid issues with blocking conditions. The new deferred local
task_work doesn't do that, which can result in spews on this being
an invalid condition:



[  112.917576] do not call blocking ops when !TASK_RUNNING; state=1 set at [<00000000ad64af64>] prepare_to_wait_exclusive+0x3f/0xd0
[  112.983088] WARNING: CPU: 1 PID: 190 at kernel/sched/core.c:9819 __might_sleep+0x5a/0x60
[  112.987240] Modules linked in:
[  112.990504] CPU: 1 PID: 190 Comm: io_uring Not tainted 6.0.0-rc6+ #1617
[  113.053136] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
[  113.133650] RIP: 0010:__might_sleep+0x5a/0x60
[  113.136507] Code: ee 48 89 df 5b 31 d2 5d e9 33 ff ff ff 48 8b 90 30 0b 00 00 48 c7 c7 90 de 45 82 c6 05 20 8b 79 01 01 48 89 d1 e8 3a 49 77 00 <0f> 0b eb d1 66 90 0f 1f 44 00 00 9c 58 f6 c4 02 74 35 65 8b 05 ed
[  113.223940] RSP: 0018:ffffc90000537ca0 EFLAGS: 00010286
[  113.232903] RAX: 0000000000000000 RBX: ffffffff8246782c RCX: ffffffff8270bcc8
IOPS=133.15K, BW=520MiB/s, IOS/call=32/31
[  113.353457] RDX: ffffc90000537b50 RSI: 00000000ffffdfff RDI: 0000000000000001
[  113.358970] RBP: 00000000000003bc R08: 0000000000000000 R09: c0000000ffffdfff
[  113.361746] R10: 0000000000000001 R11: ffffc90000537b48 R12: ffff888103f97280
[  113.424038] R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
[  113.428009] FS:  00007f67ae7fc700(0000) GS:ffff88842fc80000(0000) knlGS:0000000000000000
[  113.432794] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  113.503186] CR2: 00007f67b8b9b3b0 CR3: 0000000102b9b005 CR4: 0000000000770ee0
[  113.507291] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  113.512669] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  113.574374] PKRU: 55555554
[  113.576800] Call Trace:
[  113.578325]  <TASK>
[  113.579799]  set_page_dirty_lock+0x1b/0x90
[  113.582411]  __bio_release_pages+0x141/0x160
[  113.673078]  ? set_next_entity+0xd7/0x190
[  113.675632]  blk_rq_unmap_user+0xaa/0x210
[  113.678398]  ? timerqueue_del+0x2a/0x40
[  113.679578]  nvme_uring_task_cb+0x94/0xb0
[  113.683025]  __io_run_local_work+0x8a/0x150
[  113.743724]  ? io_cqring_wait+0x33d/0x500
[  113.746091]  io_run_local_work.part.76+0x2e/0x60
[  113.750091]  io_cqring_wait+0x2e7/0x500
[  113.752395]  ? trace_event_raw_event_io_uring_req_failed+0x180/0x180
[  113.823533]  __x64_sys_io_uring_enter+0x131/0x3c0
[  113.827382]  ? switch_fpu_return+0x49/0xc0
[  113.830753]  do_syscall_64+0x34/0x80
[  113.832620]  entry_SYSCALL_64_after_hwframe+0x5e/0xc8

Ensure that we mark current as TASK_RUNNING for deferred task_work
as well.

Fixes: c0e0d6ba25 ("io_uring: add IORING_SETUP_DEFER_TASKRUN")
Reported-by: Stefan Roesch <shr@fb.com>
Reviewed-by: Dylan Yudaken <dylany@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 19:39:35 -06:00
Pavel Begunkov 493108d95f io_uring/net: zerocopy sendmsg
Add a zerocopy version of sendmsg.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6aabc4bdfc0ec78df6ec9328137e394af9d4e7ef.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov c4c0009e0b io_uring/net: combine fail handlers
Merge io_send_zc_fail() into io_sendrecv_fail(), saves a few lines of
code and some headache for following patch.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e0eba1d577413aef5602cd45f588b9230207082d.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov b0e9b5517e io_uring/net: rename io_sendzc()
Simple renaming of io_sendzc*() functions in preparatio to adding
a zerocopy sendmsg variant.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/265af46829e6076dd220011b1858dc3151969226.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov 516e82f0e0 io_uring/net: support non-zerocopy sendto
We have normal sends, but what is missing is sendto-like requests. Add
sendto() capabilities to IORING_OP_SEND by passing in addr just as we do
for IORING_OP_SEND_ZC.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/69fbd8b2cb830e57d1bf9ec351e9bf95c5b77e3f.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov 6ae61b7aa2 io_uring/net: refactor io_setup_async_addr
Instead of passing the right address into io_setup_async_addr() only
specify local on-stack storage and let the function infer where to grab
it from. It optimises out one local variable we have to deal with.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6bfa9ab810d776853eb26ed59301e2536c3a5471.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov 5693bcce89 io_uring/net: don't lose partial send_zc on fail
Partial zc send may end up in io_req_complete_failed(), which not only
would return invalid result but also mask out the notification leading
to lifetime issues.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5673285b5e83e6ceca323727b4ddaa584b5cc91e.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov 7e6b638ed5 io_uring/net: don't lose partial send/recv on fail
Just as with rw, partial send/recv may end up in
io_req_complete_failed() and loose the result, make sure we return the
number of bytes processed.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a4ff95897b5419356fca9ea55db91ac15b2975f9.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov 47b4c68660 io_uring/rw: don't lose partial IO result on fail
A partially done read/write may end up in io_req_complete_failed() and
loose the result, make sure we return the number of bytes processed.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/05e0879c226bcd53b441bf92868eadd4bf04e2fc.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov a47b255e90 io_uring: add custom opcode hooks on fail
Sometimes we have to do a little bit of a fixup on a request failuer in
io_req_complete_failed(). Add a callback in opdef for that.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b734cff4e67cb30cca976b9face321023f37549a.1663668091.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Jens Axboe 3b8fdd1dc3 io_uring/fdinfo: fix sqe dumping for IORING_SETUP_SQE128
If we have doubly sized SQEs, then we need to shift the sq index by 1
to account for using two entries for a single request. The CQE dumping
gets this right, but the SQE one does not.

Improve the SQE dumping in general, the information dumped is pretty
sparse and doesn't even cover the whole basic part of the SQE. Include
information on the extended part of the SQE, if doubly sized SQEs are
in use. A typical dump now looks like the following:

[...]
SQEs:	32
   32: opcode:URING_CMD, fd:0, flags:1, off:3225964160, addr:0x0, rw_flags:0x0, buf_index:0 user_data:2721, e0:0x0, e1:0xffffb8041000, e2:0x100000000000, e3:0x5500, e4:0x7, e5:0x0, e6:0x0, e7:0x0
   33: opcode:URING_CMD, fd:0, flags:1, off:3225964160, addr:0x0, rw_flags:0x0, buf_index:0 user_data:2722, e0:0x0, e1:0xffffb8043000, e2:0x100000000000, e3:0x5508, e4:0x7, e5:0x0, e6:0x0, e7:0x0
   34: opcode:URING_CMD, fd:0, flags:1, off:3225964160, addr:0x0, rw_flags:0x0, buf_index:0 user_data:2723, e0:0x0, e1:0xffffb8045000, e2:0x100000000000, e3:0x5510, e4:0x7, e5:0x0, e6:0x0, e7:0x0
[...]

Fixes: ebdeb7c01d ("io_uring: add support for 128-byte SQEs")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Jens Axboe 4f731705cc io_uring/fdinfo: get rid of unnecessary is_cqe32 variable
We already have the cq_shift, just use that to tell if we have doubly
sized CQEs or not.

While in there, cleanup the CQE32 vs normal CQE size printing.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:02 -06:00
Pavel Begunkov c0dc995eb2 io_uring: remove unused return from io_disarm_next
We removed conditional io_commit_cqring_flush() guarding against
spurious eventfd and the io_disarm_next()'s return value is not used
anymore, just void it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9a441c9a32a58bcc586076fa9a7d0dc33f1fb3cb.1662652536.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:01 -06:00
Pavel Begunkov 7924fdfeea io_uring: add fast path for io_run_local_work()
We'll grab uring_lock and call __io_run_local_work() with several
atomics inside even if there are no task works. Skip it if ->work_llist
is empty.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/f6a885f372bad2d77d9cd87341b0a86a4000c0ff.1662652536.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:01 -06:00
Pavel Begunkov 1f8d5bbe98 io_uring/iopoll: unify tw breaking logic
Let's keep checks for whether to break the iopoll loop or not same for
normal and defer tw, this includes ->cached_cq_tail checks guarding
against polling more than asked for.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d2fa8a44f8114f55a4807528da438cde93815360.1662652536.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:15:01 -06:00
Pavel Begunkov 9d54bd6a3b io_uring/iopoll: fix unexpected returns
We may propagate a positive return value of io_run_task_work() out of
io_iopoll_check(), which breaks our tests. io_run_task_work() doesn't
return anything useful for us, ignore the return value.

Fixes: c0e0d6ba25 ("io_uring: add IORING_SETUP_DEFER_TASKRUN")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/c442bb87f79cea10b3f857cbd4b9a4f0a0493fa3.1662652536.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:14:59 -06:00
Pavel Begunkov 6567506b68 io_uring: disallow defer-tw run w/ no submitters
We try to restrict CQ waiters when IORING_SETUP_DEFER_TASKRUN is set,
but if nothing has been submitted yet it'll allow any waiter, which
violates the contract.

Fixes: c0e0d6ba25 ("io_uring: add IORING_SETUP_DEFER_TASKRUN")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/b4f0d3f14236d7059d08c5abe2661ef0b78b5528.1662652536.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:14:55 -06:00
Pavel Begunkov 76de6749d1 io_uring: further limit non-owner defer-tw cq waiting
In case of DEFER_TASK_WORK we try to restrict waiters to only one task,
which is also the only submitter; however, we don't do it reliably,
which might be very confusing and backfire in the future. E.g. we
currently allow multiple tasks in io_iopoll_check().

Fixes: c0e0d6ba25 ("io_uring: add IORING_SETUP_DEFER_TASKRUN")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/94c83c0a7fe468260ee2ec31bdb0095d6e874ba2.1662652536.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 13:14:46 -06:00
Pavel Begunkov ac9e5784bb io_uring/net: use io_sr_msg for sendzc
Reuse struct io_sr_msg for zerocopy sends, which is handy. There is
only one zerocopy specific field, namely .notif, and we have enough
space for it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/408c5b1b2d8869e1a12da5f5a78ed72cac112149.1662639236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Pavel Begunkov 0b048557db io_uring/net: refactor io_sr_msg types
In preparation for using struct io_sr_msg for zerocopy sends, clean up
types. First, flags can be u16 as it's provided by the userspace in u16
ioprio, as well as addr_len. This saves us 4 bytes. Also use unsigned
for size and done_io, both are as well limited to u32.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/42c2639d6385b8b2181342d2af3a42d3b1c5bcd2.1662639236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Pavel Begunkov cd9021e88f io_uring/net: add non-bvec sg chunking callback
Add a sg_from_iter() for when we initiate non-bvec zerocopy sends, which
helps us to remove some extra steps from io_sg_from_iter(). The only
thing the new function has to do before giving control away to
__zerocopy_sg_from_iter() is to check if the skb has managed frags and
downgrade them if so.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/cda3dea0d36f7931f63a70f350130f085ac3f3dd.1662639236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Pavel Begunkov 6bf8ad25fc io_uring/net: io_async_msghdr caches for sendzc
We already keep io_async_msghdr caches for normal send/recv requests,
use them also for zerocopy send.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/42fa615b6e0be25f47a685c35d7b5e4f1b03d348.1662639236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Pavel Begunkov 858c293e5d io_uring/net: use async caches for async prep
send/recv have async_data caches but there are only used from within
issue handlers. Extend their use also to ->prep_async, should be handy
with links and IOSQE_ASYNC.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b9a2264b807582a97ed606c5bfcdc2399384e8a5.1662639236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Pavel Begunkov 95eafc74be io_uring/net: reshuffle error handling
We should prioritise send/recv retry cases over failures, they're more
important. Shuffle -ERESTARTSYS after we handled retries.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d9059691b30d0963b7269fa4a0c81ee7720555e6.1662639236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Pavel Begunkov e9a8842854 io_uring: use io_cq_lock consistently
There is one place when we forgot to change hand coded spin locking with
io_cq_lock(), change it to be more consistent. Note, the unlock part is
already __io_cq_unlock_post().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/91699b9a00a07128f7ca66136bdbbfc67a64659e.1662639236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Pavel Begunkov 385c609f9b io_uring: kill an outdated comment
Request referencing has changed a while ago and there is no notion left
of submission/completion references, kill an outdated comment.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/38902e7229d68cecd62702436d627d4858b0d9d4.1662639236.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Dylan Yudaken 4ab9d46507 io_uring: allow buffer recycling in READV
In commit 934447a603 ("io_uring: do not recycle buffer in READV") a
temporary fix was put in io_kbuf_recycle to simply never recycle READV
buffers.

Instead of that, rather treat READV with REQ_F_BUFFER_SELECTED the same as
a READ with REQ_F_BUFFER_SELECTED. Since READV requires iov_len of 1 they
are essentially the same.
In order to do this inside io_prep_rw() add some validation to check that
it is in fact only length 1, and also extract the length of the buffer at
prep time.

This allows removal of the io_iov_buffer_select codepaths as they are only
used from the READV op.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220907165152.994979-1-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Jens Axboe de97fcb303 fs: add batch and poll flags to the uring_cmd_iopoll() handler
We need the poll_flags to know how to poll for the IO, and we should
have the batch structure in preparation for supporting batched
completions with iopoll.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Jens Axboe dac6a0eae7 io_uring: ensure iopoll runs local task work as well
Combine the two checks we have for task_work running and whether or not
we need to shuffle the mutex into one, so we unify how task_work is run
in the iopoll loop. This helps ensure that local task_work is run when
needed, and also optimizes that path to avoid a mutex shuffle if it's
not needed.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Jens Axboe 8ac5d85a89 io_uring: add local task_work run helper that is entered locked
We have a few spots that drop the mutex just to run local task_work,
which immediately tries to grab it again. Add a helper that just passes
in whether we're locked already.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:43 -06:00
Jens Axboe a1119fb071 io_uring: cleanly separate request types for iopoll
After the addition of iopoll support for passthrough, there's a bit of
a mixup here. Clean it up and get rid of the casting for the passthrough
command type.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Kanchan Joshi 5756a3a7e7 io_uring: add iopoll infrastructure for io_uring_cmd
Put this up in the same way as iopoll is done for regular read/write IO.
Make place for storing a cookie into struct io_uring_cmd on submission.
Perform the completion using the ->uring_cmd_iopoll handler.

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Link: https://lore.kernel.org/r/20220823161443.49436-3-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Dylan Yudaken f75d5036d0 io_uring: trace local task work run
Add tracing for io_run_local_task_work

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220830125013.570060-8-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Dylan Yudaken 21a091b970 io_uring: signal registered eventfd to process deferred task work
Some workloads rely on a registered eventfd (via
io_uring_register_eventfd(3)) in order to wake up and process the
io_uring.

In the case of a ring setup with IORING_SETUP_DEFER_TASKRUN, that eventfd
also needs to be signalled when there are tasks to run.

This changes an old behaviour which assumed 1 eventfd signal implied at
least 1 CQE, however only when this new flag is set (and so old users will
not notice). This should be expected with the IORING_SETUP_DEFER_TASKRUN
flag as it is not guaranteed that every task will result in a CQE.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220830125013.570060-7-dylany@fb.com
[axboe: fold in call_rcu() serialization fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Dylan Yudaken d8e9214f11 io_uring: move io_eventfd_put
Non functional change: move this function above io_eventfd_signal so it
can be used from there

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220830125013.570060-6-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Dylan Yudaken c0e0d6ba25 io_uring: add IORING_SETUP_DEFER_TASKRUN
Allow deferring async tasks until the user calls io_uring_enter(2) with
the IORING_ENTER_GETEVENTS flag. Enable this mode with a flag at
io_uring_setup time. This functionality requires that the later
io_uring_enter will be called from the same submission task, and therefore
restrict this flag to work only when IORING_SETUP_SINGLE_ISSUER is also
set.

Being able to hand pick when tasks are run prevents the problem where
there is current work to be done, however task work runs anyway.

For example, a common workload would obtain a batch of CQEs, and process
each one. Interrupting this to additional taskwork would add latency but
not gain anything. If instead task work is deferred to just before more
CQEs are obtained then no additional latency is added.

The way this is implemented is by trying to keep task work local to a
io_ring_ctx, rather than to the submission task. This is required, as the
application will want to wake up only a single io_ring_ctx at a time to
process work, and so the lists of work have to be kept separate.

This has some other benefits like not having to check the task continually
in handle_tw_list (and potentially unlocking/locking those), and reducing
locks in the submit & process completions path.

There are networking cases where using this option can reduce request
latency by 50%. For example a contrived example using [1] where the client
sends 2k data and receives the same data back while doing some system
calls (to trigger task work) shows this reduction. The reason ends up
being that if sending responses is delayed by processing task work, then
the client side sits idle. Whereas reordering the sends first means that
the client runs it's workload in parallel with the local task work.

[1]:
Using https://github.com/DylanZA/netbench/tree/defer_run
Client:
./netbench  --client_only 1 --control_port 10000 --host <host> --tx "epoll --threads 16 --per_thread 1 --size 2048 --resp 2048 --workload 1000"
Server:
./netbench  --server_only 1 --control_port 10000  --rx "io_uring --defer_taskrun 0 --workload 100"   --rx "io_uring  --defer_taskrun 1 --workload 100"

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220830125013.570060-5-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Dylan Yudaken 2327337b88 io_uring: do not run task work at the start of io_uring_enter
This is not needed, and it is normally better to wait for task work until
after submissions. This will allow greater batching if either work arrives
in the meanwhile, or if the submissions cause task work to be queued up.

For SQPOLL this also no longer runs task work, but this is handled inside
the SQPOLL loop anyway.

For IOPOLL io_iopoll_check will run task work anyway

And otherwise io_cqring_wait will run task work

Suggested-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220830125013.570060-4-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Dylan Yudaken b4c98d59a7 io_uring: introduce io_has_work
This will be used later to know if the ring has outstanding work. Right
now just if there is overflow CQEs to copy to the main CQE ring, but later
will include deferred tasks

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220830125013.570060-3-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Dylan Yudaken 32d91f0590 io_uring: remove unnecessary variable
'running' is set once and read once, so can easily just remove it

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220830125013.570060-2-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-21 10:30:42 -06:00
Linus Torvalds 38eddeedbb io_uring-6.0-2022-09-18
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Merge tag 'io_uring-6.0-2022-09-18' of git://git.kernel.dk/linux

Pull io_uring fixes from Jens Axboe:
 "Nothing really major here, but figured it'd be nicer to just get these
  flushed out for -rc6 so that the 6.1 branch will have them as well.
  That'll make our lives easier going forward in terms of development,
  and avoid trivial conflicts in this area.

   - Simple trace rename so that the returned opcode name is consistent
     with the enum definition (Stefan)

   - Send zc rsrc request vs notification lifetime fix (Pavel)"

* tag 'io_uring-6.0-2022-09-18' of git://git.kernel.dk/linux:
  io_uring/opdef: rename SENDZC_NOTIF to SEND_ZC
  io_uring/net: fix zc fixed buf lifetime
2022-09-18 09:25:27 -07:00
Stefan Metzmacher 9bd3f72822 io_uring/opdef: rename SENDZC_NOTIF to SEND_ZC
It's confusing to see the string SENDZC_NOTIF in ftrace output
when using IORING_OP_SEND_ZC.

Fixes: b48c312be0 ("io_uring/net: simplify zerocopy send user API")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: io-uring@vger.kernel.org
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8e5cd8616919c92b6c3c7b6ea419fdffd5b97f3c.1663363798.git.metze@samba.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-18 06:59:13 -06:00
Pavel Begunkov e3366e0234 io_uring/net: fix zc fixed buf lifetime
Notifications usually outlive requests, so we need to pin buffers with
it by assigning a rsrc to it instead of the request.

Fixed: b48c312be0 ("io_uring/net: simplify zerocopy send user API")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/dd6406ff8a90887f2b36ed6205dac9fda17c1f35.1663366886.git.asml.silence@gmail.com
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-18 05:07:51 -06:00
Linus Torvalds 0158137d81 io_uring-6.0-2022-09-16
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Merge tag 'io_uring-6.0-2022-09-16' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:
 "Two small patches:

   - Fix using an unsigned type for the return value, introduced in this
     release (Pavel)

   - Stable fix for a missing check for a fixed file on put (me)"

* tag 'io_uring-6.0-2022-09-16' of git://git.kernel.dk/linux-block:
  io_uring/msg_ring: check file type before putting
  io_uring/rw: fix error'ed retry return values
2022-09-16 06:50:25 -07:00
Jens Axboe fc7222c3a9 io_uring/msg_ring: check file type before putting
If we're invoked with a fixed file, follow the normal rules of not
calling io_fput_file(). Fixed files are permanently registered to the
ring, and do not need putting separately.

Cc: stable@vger.kernel.org
Fixes: aa184e8671 ("io_uring: don't attempt to IOPOLL for MSG_RING requests")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-15 11:44:35 -06:00
Pavel Begunkov 62bb0647b1 io_uring/rw: fix error'ed retry return values
Kernel test robot reports that we test negativity of an unsigned in
io_fixup_rw_res() after a recent change, which masks error codes and
messes up the return value in case I/O is re-retried and failed with
an error.

Fixes: 4d9cb92ca4 ("io_uring/rw: fix short rw error handling")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9754a0970af1861e7865f9014f735c70dc60bf79.1663071587.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-13 07:47:11 -06:00
Linus Torvalds d2b768c3d4 io_uring-6.0-2022-09-09
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Merge tag 'io_uring-6.0-2022-09-09' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:

 - Removed function that became unused after last week's merge (Jiapeng)

 - Two small fixes for kbuf recycling (Pavel)

 - Include address copy for zc send for POLLFIRST (Pavel)

 - Fix for short IO handling in the normal read/write path (Pavel)

* tag 'io_uring-6.0-2022-09-09' of git://git.kernel.dk/linux-block:
  io_uring/rw: fix short rw error handling
  io_uring/net: copy addr for zc on POLL_FIRST
  io_uring: recycle kbuf recycle on tw requeue
  io_uring/kbuf: fix not advancing READV kbuf ring
  io_uring/notif: Remove the unused function io_notif_complete()
2022-09-09 14:57:18 -04:00
Pavel Begunkov 4d9cb92ca4 io_uring/rw: fix short rw error handling
We have a couple of problems, first reports of unexpected link breakage
for reads when cqe->res indicates that the IO was done in full. The
reason here is partial IO with retries.

TL;DR; we compare the result in __io_complete_rw_common() against
req->cqe.res, but req->cqe.res doesn't store the full length but rather
the length left to be done. So, when we pass the full corrected result
via kiocb_done() -> __io_complete_rw_common(), it fails.

The second problem is that we don't try to correct res in
io_complete_rw(), which, for instance, might be a problem for O_DIRECT
but when a prefix of data was cached in the page cache. We also
definitely don't want to pass a corrected result into io_rw_done().

The fix here is to leave __io_complete_rw_common() alone, always pass
not corrected result into it and fix it up as the last step just before
actually finishing the I/O.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://github.com/axboe/liburing/issues/643
Reported-by: Beld Zhang <beldzhang@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-09 08:57:57 -06:00
Pavel Begunkov 3c8400532d io_uring/net: copy addr for zc on POLL_FIRST
Every time we return from an issue handler and expect the request to be
retried we should also setup it for async exec ourselves. Do that when
we return on IORING_RECVSEND_POLL_FIRST in io_sendzc(), otherwise it'll
re-read the address, which might be a surprise for the userspace.

Fixes: 092aeedb75 ("io_uring: allow to pass addr into sendzc")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/ab1d0657890d6721339c56d2e161a4bba06f85d0.1662642013.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-08 08:28:38 -06:00
Pavel Begunkov 336d28a8f3 io_uring: recycle kbuf recycle on tw requeue
When we queue a request via tw for execution it's not going to be
executed immediately, so when io_queue_async() hits IO_APOLL_READY
and queues a tw but doesn't try to recycle/consume the buffer some other
request may try to use the the buffer.

Fixes: c7fb19428d ("io_uring: add support for ring mapped supplied buffers")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a19bc9e211e3184215a58e129b62f440180e9212.1662480490.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-07 10:36:10 -06:00
Pavel Begunkov df6d3422d3 io_uring/kbuf: fix not advancing READV kbuf ring
When we don't recycle a selected ring buffer we should advance the head
of the ring, so don't just skip io_kbuf_recycle() for IORING_OP_READV
but adjust the ring.

Fixes: 934447a603 ("io_uring: do not recycle buffer in READV")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/a6d85e2611471bcb5d5dcd63a8342077ddc2d73d.1662480490.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-07 10:36:10 -06:00
Jiapeng Chong 4fa07edbb7 io_uring/notif: Remove the unused function io_notif_complete()
The function io_notif_complete() is defined in the notif.c file, but not
called elsewhere, so delete this unused function.

io_uring/notif.c:24:20: warning: unused function 'io_notif_complete' [-Wunused-function].

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2047
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/20220905020436.51894-1-jiapeng.chong@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-05 11:42:39 -06:00
Linus Torvalds cec53f4c8d io_uring-6.0-2022-09-02
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Merge tag 'io_uring-6.0-2022-09-02' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:

 - A single fix for over-eager retries for networking (Pavel)

 - Revert the notification slot support for zerocopy sends.

   It turns out that even after more than a year or development and
   testing, there's not full agreement on whether just using plain
   ordered notifications is Good Enough to avoid the complexity of using
   the notifications slots. Because of that, we decided that it's best
   left to a future final decision.

   We can always bring back this feature, but we can't really change it
   or remove it once we've released 6.0 with it enabled. The reverts
   leave the usual CQE notifications as the primary interface for
   knowing when data was sent, and when it was acked. (Pavel)

* tag 'io_uring-6.0-2022-09-02' of git://git.kernel.dk/linux-block:
  selftests/net: return back io_uring zc send tests
  io_uring/net: simplify zerocopy send user API
  io_uring/notif: remove notif registration
  Revert "io_uring: rename IORING_OP_FILES_UPDATE"
  Revert "io_uring: add zc notification flush requests"
  selftests/net: temporarily disable io_uring zc test
  io_uring/net: fix overexcessive retries
2022-09-02 16:37:01 -07:00
Al Viro e81f574da0 __io_setxattr(): constify path
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-09-01 17:39:05 -04:00
Pavel Begunkov b48c312be0 io_uring/net: simplify zerocopy send user API
Following user feedback, this patch simplifies zerocopy send API. One of
the main complaints is that the current API is difficult with the
userspace managing notification slots, and then send retries with error
handling make it even worse.

Instead of keeping notification slots change it to the per-request
notifications model, which posts both completion and notification CQEs
for each request when any data has been sent, and only one CQE if it
fails. All notification CQEs will have IORING_CQE_F_NOTIF set and
IORING_CQE_F_MORE in completion CQEs indicates whether to wait a
notification or not.

IOSQE_CQE_SKIP_SUCCESS is disallowed with zerocopy sends for now.

This is less flexible, but greatly simplifies the user API and also the
kernel implementation. We reuse notif helpers in this patch, but in the
future there won't be need for keeping two requests.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/95287640ab98fc9417370afb16e310677c63e6ce.1662027856.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01 09:13:33 -06:00
Pavel Begunkov 57f332246a io_uring/notif: remove notif registration
We're going to remove the userspace exposed zerocopy notification API,
remove notification registration.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/6ff00b97be99869c386958a990593c9c31cf105b.1662027856.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01 09:13:33 -06:00
Pavel Begunkov d9808ceb31 Revert "io_uring: rename IORING_OP_FILES_UPDATE"
This reverts commit 4379d5f15b.

We removed notification flushing, also cleanup uapi preparation changes
to not pollute it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/89edc3905350f91e1b6e26d9dbf42ee44fd451a2.1662027856.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01 09:13:33 -06:00
Pavel Begunkov 23c12d5fc0 Revert "io_uring: add zc notification flush requests"
This reverts commit 492dddb4f6.

Soon we won't have the very notion of notification flushing, so remove
notification flushing requests.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8850334ca56e65b413cb34fd158db81d7b2865a3.1662027856.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01 09:13:33 -06:00
Linus Torvalds 9c9d1896fa lsm/stable-6.0 PR 20220829
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Merge tag 'lsm-pr-20220829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm

Pull LSM support for IORING_OP_URING_CMD from Paul Moore:
 "Add SELinux and Smack controls to the io_uring IORING_OP_URING_CMD.

  These are necessary as without them the IORING_OP_URING_CMD remains
  outside the purview of the LSMs (Luis' LSM patch, Casey's Smack patch,
  and my SELinux patch). They have been discussed at length with the
  io_uring folks, and Jens has given his thumbs-up on the relevant
  patches (see the commit descriptions).

  There is one patch that is not strictly necessary, but it makes
  testing much easier and is very trivial: the /dev/null
  IORING_OP_URING_CMD patch."

* tag 'lsm-pr-20220829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  Smack: Provide read control for io_uring_cmd
  /dev/null: add IORING_OP_URING_CMD support
  selinux: implement the security_uring_cmd() LSM hook
  lsm,io_uring: add LSM hooks for the new uring_cmd file op
2022-08-31 09:23:16 -07:00
Pavel Begunkov dfb58b1796 io_uring/net: fix overexcessive retries
Length parameter of io_sg_from_iter() can be smaller than the iterator's
size, as it's with TCP, so when we set from->count at the end of the
function we truncate the iterator forcing TCP to return preliminary with
a short send. It affects zerocopy sends with large payload sizes and
leads to retries and possible request failures.

Fixes: 3ff1a0d395 ("io_uring: enable managed frags with register buffers")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0bc0d5179c665b4ef5c328377c84c7a1f298467e.1661530037.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-26 10:31:42 -06:00
Luis Chamberlain 2a58401240 lsm,io_uring: add LSM hooks for the new uring_cmd file op
io-uring cmd support was added through ee692a21e9 ("fs,io_uring:
add infrastructure for uring-cmd"), this extended the struct
file_operations to allow a new command which each subsystem can use
to enable command passthrough. Add an LSM specific for the command
passthrough which enables LSMs to inspect the command details.

This was discussed long ago without no clear pointer for something
conclusive, so this enables LSMs to at least reject this new file
operation.

[0] https://lkml.kernel.org/r/8adf55db-7bab-f59d-d612-ed906b948d19@schaufler-ca.com

Cc: stable@vger.kernel.org
Fixes: ee692a21e9 ("fs,io_uring: add infrastructure for uring-cmd")
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-08-26 11:19:43 -04:00
Pavel Begunkov 581711c466 io_uring/net: save address for sendzc async execution
We usually copy all bits that a request needs from the userspace for
async execution, so the userspace can keep them on the stack. However,
send zerocopy violates this pattern for addresses and may reloads it
e.g. from io-wq. Save the address if any in ->async_data as usual.

Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d7512d7aa9abcd36e9afe1a4d292a24cb2d157e5.1661342812.git.asml.silence@gmail.com
[axboe: fold in incremental fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-25 07:52:30 -06:00
Pavel Begunkov 5916943943 io_uring: conditional ->async_data allocation
There are opcodes that need ->async_data only in some cases and
allocation it unconditionally may hurt performance. Add an option to
opdef to make move the allocation part from the core io_uring to opcode
specific code.
Note, we can't just set opdef->async_size to zero because there are
other helpers that rely on it, e.g. io_alloc_async_data().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9dc62be9e88dd0ed63c48365340e8922d2498293.1661342812.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-24 08:57:28 -06:00
Pavel Begunkov 53bdc88aac io_uring/notif: order notif vs send CQEs
Currently, there is no ordering between notification CQEs and
completions of the send flushing it, this quite complicates the
userspace, especially since we don't flush notification when the
send(+flush) request fails, i.e. there will be only one CQE. What we
can do is to make sure that notification completions come only after
sends.

The easiest way to achieve this is to not try to complete a notification
inline from io_sendzc() but defer it to task_work, considering that
io-wq sendzc is disallowed CQEs will be naturally ordered because
task_works will only be executed after we're done with submission and so
inline completion.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/cddfd1c2bf91f22b9fe08e13b7dffdd8f858a151.1661342812.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-24 08:57:28 -06:00
Pavel Begunkov 986e263def io_uring/net: fix indentation
Fix up indentation before we get complaints from tooling.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/bd5754e3764215ccd7fb04cd636ea9167aaa275d.1661342812.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-24 08:57:15 -06:00
Pavel Begunkov 5a848b7c9e io_uring/net: fix zc send link failing
Failed requests should be marked with req_set_fail(), so links and cqe
skipping work correctly, which is missing in io_sendzc(). Note,
io_sendzc() return IOU_OK on failure, so the core code won't do the
cleanup for us.

Fixes: 06a5464be8 ("io_uring: wire send zc request type")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e47d46fda9db30154ce66a549bb0d3380b780520.1661342812.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-24 08:57:00 -06:00
Pavel Begunkov 2cacedc873 io_uring/net: fix must_hold annotation
Fix up the io_alloc_notif()'s __must_hold as we don't have a ctx
argument there but should get it from the slot instead.

Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/cbb0a920f18e0aed590bf58300af817b9befb8a3.1661342812.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-24 08:57:00 -06:00
Kanchan Joshi a9c3eda7ea io_uring: fix submission-failure handling for uring-cmd
If ->uring_cmd returned an error value different from -EAGAIN or
-EIOCBQUEUED, it gets overridden with IOU_OK. This invites trouble
as caller (io_uring core code) handles IOU_OK differently than other
error codes.
Fix this by returning the actual error code.

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-23 09:46:17 -06:00
Jens Axboe 47abea041f io_uring: fix off-by-one in sync cancelation file check
The passed in index should be validated against the number of registered
files we have, it needs to be smaller than the index value to avoid going
one beyond the end.

Fixes: 78a861b949 ("io_uring: add sync cancelation API through io_uring_register()")
Reported-by: Luo Likang <luolikang@nsfocus.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-23 07:26:08 -06:00
Pavel Begunkov 3f743e9bbb io_uring/net: use right helpers for async_data
There is another spot where we check ->async_data directly instead of
using req_has_async_data(), which is the way to do it, fix it up.

Fixes: 43e0bbbd0b ("io_uring: add netmsg cache")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/42f33b9a81dd6ae65dda92f0372b0ff82d548517.1660822636.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-18 07:27:20 -06:00
Pavel Begunkov 5993000dc6 io_uring/notif: raise limit on notification slots
1024 notification slots is rather an arbitrary value, raise it up,
everything is accounted to memcg.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/eb78a0a5f2fa5941f8e845cdae5fb399bf7ba0be.1660566179.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-15 21:34:00 -06:00
Pavel Begunkov 86dc8f23bb io_uring/net: improve zc addr import error handling
We may account memory to a memcg of a request that didn't even got to
the network layer. It's not a bug as it'll be routinely cleaned up on
flush, but it might be confusing for the userspace.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b8aae61f4c3ddc4da97c1da876bb73871f352d50.1660566179.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-15 21:34:00 -06:00
Pavel Begunkov 063604265f io_uring/net: use right helpers for async recycle
We have a helper that checks for whether a request contains anything in
->async_data or not, namely req_has_async_data(). It's better to use it
as it might have some extra considerations.

Fixes: 43e0bbbd0b ("io_uring: add netmsg cache")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b7414da4e7c3c32c31fc02dfd1355af4ccf4ca5f.1660566179.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-15 21:34:00 -06:00
Linus Torvalds 1da8cf961b io_uring-6.0-2022-08-13
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Merge tag 'io_uring-6.0-2022-08-13' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:

 - Regression fix for this merge window, fixing a wrong order of
   arguments for io_req_set_res() for passthru (Dylan)

 - Fix for the audit code leaking context memory (Peilin)

 - Ensure that provided buffers are memcg accounted (Pavel)

 - Correctly handle short zero-copy sends (Pavel)

 - Sparse warning fixes for the recvmsg multishot command (Dylan)

 - Error handling fix for passthru (Anuj)

 - Remove randomization of struct kiocb fields, to avoid it growing in
   size if re-arranged in such a fashion that it grows more holes or
   padding (Keith, Linus)

 - Small series improving type safety of the sqe fields (Stefan)

* tag 'io_uring-6.0-2022-08-13' of git://git.kernel.dk/linux-block:
  io_uring: add missing BUILD_BUG_ON() checks for new io_uring_sqe fields
  io_uring: make io_kiocb_to_cmd() typesafe
  fs: don't randomize struct kiocb fields
  io_uring: consistently make use of io_notif_to_data()
  io_uring: fix error handling for io_uring_cmd
  io_uring: fix io_recvmsg_prep_multishot sparse warnings
  io_uring/net: send retry for zerocopy
  io_uring: mem-account pbuf buckets
  audit, io_uring, io-wq: Fix memory leak in io_sq_thread() and io_wqe_worker()
  io_uring: pass correct parameters to io_req_set_res
2022-08-13 13:28:54 -07:00
Stefan Metzmacher 9c71d39aa0 io_uring: add missing BUILD_BUG_ON() checks for new io_uring_sqe fields
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Link: https://lore.kernel.org/r/ffcaf8dc4778db4af673822df60dbda6efdd3065.1660201408.git.metze@samba.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-12 17:01:00 -06:00
Stefan Metzmacher f2ccb5aed7 io_uring: make io_kiocb_to_cmd() typesafe
We need to make sure (at build time) that struct io_cmd_data is not
casted to a structure that's larger.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Link: https://lore.kernel.org/r/c024cdf25ae19fc0319d4180e2298bade8ed17b8.1660201408.git.metze@samba.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-12 17:01:00 -06:00
Stefan Metzmacher da2634e89c io_uring: consistently make use of io_notif_to_data()
This makes the assignment typesafe. It prepares
changing io_kiocb_to_cmd() in the next commit.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Link: https://lore.kernel.org/r/8da6e9d12cf95ad4bc73274406d12bca7aabf72e.1660201408.git.metze@samba.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-11 10:56:13 -06:00
Anuj Gupta 3ed159c984 io_uring: fix error handling for io_uring_cmd
Commit 97b388d70b ("io_uring: handle completions in the core") moved the
error handling from handler to core. But for io_uring_cmd handler we end
up completing more than once (both in handler and in core) leading to
use_after_free.
Change io_uring_cmd handler to avoid calling io_uring_cmd_done in case
of error.

Fixes: 97b388d70b ("io_uring: handle completions in the core")
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20220811091459.6929-1-anuj20.g@samsung.com
[axboe: fix ret vs req typo]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-11 10:56:00 -06:00
Dylan Yudaken d1f6222c49 io_uring: fix io_recvmsg_prep_multishot sparse warnings
Fix casts missing the __user parts. This seemed to only cause errors on
the alpha build, or if checked with sparse, but it was definitely an
oversight.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 9bb66906f2 ("io_uring: support multishot in recvmsg")
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220805115450.3921352-1-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-05 08:41:18 -06:00
Pavel Begunkov 4a933e6208 io_uring/net: send retry for zerocopy
io_uring handles short sends/recvs for stream sockets when MSG_WAITALL
is set, however new zerocopy send is inconsistent in this regard, which
might be confusing. Handle short sends.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b876a4838597d9bba4f3215db60d72c33c448ad0.1659622472.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-04 08:35:16 -06:00
Pavel Begunkov cc18cc5e82 io_uring: mem-account pbuf buckets
Potentially, someone may create as many pbuf bucket as there are indexes
in an xarray without any other restrictions bounding our memory usage,
put memory needed for the buckets under memory accounting.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d34c452e45793e978d26e2606211ec9070d329ea.1659622312.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-04 08:35:07 -06:00
Peilin Ye f482aa9865 audit, io_uring, io-wq: Fix memory leak in io_sq_thread() and io_wqe_worker()
Currently @audit_context is allocated twice for io_uring workers:

  1. copy_process() calls audit_alloc();
  2. io_sq_thread() or io_wqe_worker() calls audit_alloc_kernel() (which
     is effectively audit_alloc()) and overwrites @audit_context,
     causing:

  BUG: memory leak
  unreferenced object 0xffff888144547400 (size 1024):
<...>
    hex dump (first 32 bytes):
      00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00  ................
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [<ffffffff8135cfc3>] audit_alloc+0x133/0x210
      [<ffffffff81239e63>] copy_process+0xcd3/0x2340
      [<ffffffff8123b5f3>] create_io_thread+0x63/0x90
      [<ffffffff81686604>] create_io_worker+0xb4/0x230
      [<ffffffff81686f68>] io_wqe_enqueue+0x248/0x3b0
      [<ffffffff8167663a>] io_queue_iowq+0xba/0x200
      [<ffffffff816768b3>] io_queue_async+0x113/0x180
      [<ffffffff816840df>] io_req_task_submit+0x18f/0x1a0
      [<ffffffff816841cd>] io_apoll_task_func+0xdd/0x120
      [<ffffffff8167d49f>] tctx_task_work+0x11f/0x570
      [<ffffffff81272c4e>] task_work_run+0x7e/0xc0
      [<ffffffff8125a688>] get_signal+0xc18/0xf10
      [<ffffffff8111645b>] arch_do_signal_or_restart+0x2b/0x730
      [<ffffffff812ea44e>] exit_to_user_mode_prepare+0x5e/0x180
      [<ffffffff844ae1b2>] syscall_exit_to_user_mode+0x12/0x20
      [<ffffffff844a7e80>] do_syscall_64+0x40/0x80

Then,

  3. io_sq_thread() or io_wqe_worker() frees @audit_context using
     audit_free();
  4. do_exit() eventually calls audit_free() again, which is okay
     because audit_free() does a NULL check.

As suggested by Paul Moore, fix it by deleting audit_alloc_kernel() and
redundant audit_free() calls.

Fixes: 5bd2182d58 ("audit,io_uring,io-wq: add some basic audit support to io_uring")
Suggested-by: Paul Moore <paul@paul-moore.com>
Cc: stable@vger.kernel.org
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Link: https://lore.kernel.org/r/20220803222343.31673-1-yepeilin.cs@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-04 08:33:54 -06:00
Linus Torvalds 5264406cdb iov_iter work, part 1 - isolated cleanups and optimizations.
One of the goals is to reduce the overhead of using ->read_iter()
 and ->write_iter() instead of ->read()/->write(); new_sync_{read,write}()
 has a surprising amount of overhead, in particular inside iocb_flags().
 That's why the beginning of the series is in this pile; it's not directly
 iov_iter-related, but it's a part of the same work...
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-work.iov_iter-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs iov_iter updates from Al Viro:
 "Part 1 - isolated cleanups and optimizations.

  One of the goals is to reduce the overhead of using ->read_iter() and
  ->write_iter() instead of ->read()/->write().

  new_sync_{read,write}() has a surprising amount of overhead, in
  particular inside iocb_flags(). That's the explanation for the
  beginning of the series is in this pile; it's not directly
  iov_iter-related, but it's a part of the same work..."

* tag 'pull-work.iov_iter-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  first_iovec_segment(): just return address
  iov_iter: massage calling conventions for first_{iovec,bvec}_segment()
  iov_iter: first_{iovec,bvec}_segment() - simplify a bit
  iov_iter: lift dealing with maxpages out of first_{iovec,bvec}_segment()
  iov_iter_get_pages{,_alloc}(): cap the maxsize with MAX_RW_COUNT
  iov_iter_bvec_advance(): don't bother with bvec_iter
  copy_page_{to,from}_iter(): switch iovec variants to generic
  keep iocb_flags() result cached in struct file
  iocb: delay evaluation of IS_SYNC(...) until we want to check IOCB_DSYNC
  struct file: use anonymous union member for rcuhead and llist
  btrfs: use IOMAP_DIO_NOSYNC
  teach iomap_dio_rw() to suppress dsync
  No need of likely/unlikely on calls of check_copy_size()
2022-08-03 13:50:22 -07:00
Ming Lei ff2557b722 io_uring: pass correct parameters to io_req_set_res
The two parameters of 'res' and 'cflags' are swapped, so fix it.
Without this fix, 'ublk del' hangs forever.

Cc: Pavel Begunkov <asml.silence@gmail.com>
Fixes: de23077eda ("io_uring: set completion results upfront")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220803120757.1668278-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-03 08:45:25 -06:00
Linus Torvalds 42df1cbf6a for-5.20/io_uring-zerocopy-send-2022-07-29
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Merge tag 'for-5.20/io_uring-zerocopy-send-2022-07-29' of git://git.kernel.dk/linux-block

Pull io_uring zerocopy support from Jens Axboe:
 "This adds support for efficient support for zerocopy sends through
  io_uring. Both ipv4 and ipv6 is supported, as well as both TCP and
  UDP.

  The core network changes to support this is in a stable branch from
  Jakub that both io_uring and net-next has pulled in, and the io_uring
  changes are layered on top of that.

  All of the work has been done by Pavel"

* tag 'for-5.20/io_uring-zerocopy-send-2022-07-29' of git://git.kernel.dk/linux-block: (34 commits)
  io_uring: notification completion optimisation
  io_uring: export req alloc from core
  io_uring/net: use unsigned for flags
  io_uring/net: make page accounting more consistent
  io_uring/net: checks errors of zc mem accounting
  io_uring/net: improve io_get_notif_slot types
  selftests/io_uring: test zerocopy send
  io_uring: enable managed frags with register buffers
  io_uring: add zc notification flush requests
  io_uring: rename IORING_OP_FILES_UPDATE
  io_uring: flush notifiers after sendzc
  io_uring: sendzc with fixed buffers
  io_uring: allow to pass addr into sendzc
  io_uring: account locked pages for non-fixed zc
  io_uring: wire send zc request type
  io_uring: add notification slot registration
  io_uring: add rsrc referencing for notifiers
  io_uring: complete notifiers in tw
  io_uring: cache struct io_notif
  io_uring: add zc notification infrastructure
  ...
2022-08-02 13:37:55 -07:00
Pavel Begunkov 14b146b688 io_uring: notification completion optimisation
We want to use all optimisations that we have for io_uring requests like
completion batching, memory caching and more but for zc notifications.
Fortunately, notification perfectly fit the request model so we can
overlay them onto struct io_kiocb and use all the infratructure.

Most of the fields of struct io_notif natively fits into io_kiocb, so we
replace struct io_notif with struct io_kiocb carrying struct
io_notif_data in the cmd cache line. Then we adapt io_alloc_notif() to
use io_alloc_req()/io_alloc_req_refill(), and kill leftovers of hand
coded caching. __io_notif_complete_tw() is converted to use io_uring's
tw infra.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9e010125175e80baf51f0ca63bdc7cc6a4a9fa56.1658913593.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-27 08:50:50 -06:00
Pavel Begunkov bd1a3783dd io_uring: export req alloc from core
We want to do request allocation out of the core io_uring code, make the
allocation functions public for other io_uring parts.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0314fedd3a02a514210ba42d4720332538c65956.1658913593.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-27 08:50:50 -06:00
Pavel Begunkov 293402e564 io_uring/net: use unsigned for flags
Use unsigned int type for msg flags.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5cfaed13d3191337b14b8664ca68b515d9e2d1b4.1658742118.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-25 09:48:25 -06:00
Pavel Begunkov 6a9ce66f4d io_uring/net: make page accounting more consistent
Make network page accounting more consistent with how buffer
registration is working, i.e. account all memory to ctx->user.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/4aacfe64bbb81b27f9ecf5d5c219c69a07e5aa56.1658742118.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-25 09:48:25 -06:00
Pavel Begunkov 2e32ba5607 io_uring/net: checks errors of zc mem accounting
mm_account_pinned_pages() may fail, don't ignore the return value.

Fixes: e29e3bd4b9 ("io_uring: account locked pages for non-fixed zc")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/dae0542ed8e6706071bb83ad3e7ad6a70d207fd9.1658742118.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-25 09:48:17 -06:00
Pavel Begunkov cb309ae49d io_uring/net: improve io_get_notif_slot types
Don't use signed int for slot indexing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e4d15aefebb5e55729dd9b5ec01ab16b70033343.1658742118.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-25 09:47:45 -06:00
Pavel Begunkov 3ff1a0d395 io_uring: enable managed frags with register buffers
io_uring's registered buffers infra has a good performant way of pinning
pages, so let's use SKBFL_MANAGED_FRAG_REFS when our requests are purely
register buffer backed.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/278731d3f20caf346cfc025fbee0b4c9ee4ed751.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov 492dddb4f6 io_uring: add zc notification flush requests
Overlay notification control onto IORING_OP_RSRC_UPDATE (former
IORING_OP_FILES_UPDATE). It allows to flush a range of zc notifications
from slots with indexes [sqe->off, sqe->off+sqe->len). If sqe->arg is
not zero, it also copies sqe->arg as a new tag for all flushed
notifications.

Note, it doesn't flush a notification of a slot if there was no requests
attached to it (since last flush or registration).

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/df13e2363400682a73dd9e71c3b990b8d1ff0333.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov 4379d5f15b io_uring: rename IORING_OP_FILES_UPDATE
IORING_OP_FILES_UPDATE will be a more generic opcode serving different
resource types, rename it into IORING_OP_RSRC_UPDATE and add subtype
handling.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0a907133907d9af3415a8a7aa1802c6aa97c03c6.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov 63809137eb io_uring: flush notifiers after sendzc
Allow to flush notifiers as a part of sendzc request by setting
IORING_SENDZC_FLUSH flag. When the sendzc request succeedes it will
flush the used [active] notifier.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e0b4d9a6797e2fd6092824fe42953db7a519bbc8.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov 10c7d33ecd io_uring: sendzc with fixed buffers
Allow zerocopy sends to use fixed buffers. There is an optimisation for
this case, the network layer don't need to reference the pages, see
SKBFL_MANAGED_FRAG_REFS, so io_uring have to ensure validity of fixed
buffers until the notifier is released.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e1d8bd1b5934e541d90c1824eb4020ae3f5f43f3.1657643355.git.asml.silence@gmail.com
[axboe: fold in 32-bit pointer cast warning fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov 092aeedb75 io_uring: allow to pass addr into sendzc
Allow to specify an address to zerocopy sends making it more like
sendto(2).

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/70417a8f7c5b51ab454690bae08adc0c187f89e8.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov e29e3bd4b9 io_uring: account locked pages for non-fixed zc
Fixed buffers are RLIMIT_MEMLOCK accounted, however it doesn't cover iovec
based zerocopy sends. Do the accounting on the io_uring side.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/19b6e3975440f59f1f6199c7ee7acf977b4eecdc.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov 06a5464be8 io_uring: wire send zc request type
Add a new io_uring opcode IORING_OP_SENDZC. The main distinction from
IORING_OP_SEND is that the user should specify a notification slot
index in sqe::notification_idx and the buffers are safe to reuse only
when the used notification is flushed and completes.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a80387c6a68ce9cf99b3b6ef6f71068468761fb7.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov bc24d6bd32 io_uring: add notification slot registration
Let the userspace to register and unregister notification slots.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a0aa8161fe3ebb2a4cc6e5dbd0cffb96e6881cf5.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:07 -06:00
Pavel Begunkov 68ef5578ef io_uring: add rsrc referencing for notifiers
In preparation to zerocopy sends with fixed buffers make notifiers to
reference the rsrc node to protect the used fixed buffers. We can't just
grab it for a send request as notifiers can likely outlive requests that
used it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3cd7a01d26837945b6982fa9cf15a63230f2ed4f.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:06 -06:00
Pavel Begunkov e58d498e81 io_uring: complete notifiers in tw
We need a task context to post CQEs but using wq is too expensive.
Try to complete notifiers using task_work and fall back to wq if fails.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/089799ab665b10b78fdc614ae6d59fa7ef0d5f91.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:06 -06:00
Pavel Begunkov eb4a299b2f io_uring: cache struct io_notif
kmalloc'ing struct io_notif is too expensive when done frequently, cache
them as many other resources in io_uring. Keep two list, the first one
is from where we're getting notifiers, it's protected by ->uring_lock.
The second is protected by ->completion_lock, to which we queue released
notifiers. Then we splice one list into another when needed.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/9dec18f7fcbab9f4bd40b96e5ae158b119945230.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:06 -06:00
Pavel Begunkov eb42cebb2c io_uring: add zc notification infrastructure
Add internal part of send zerocopy notifications. There are two main
structures, the first one is struct io_notif, which carries inside
struct ubuf_info and maps 1:1 to it. io_uring will be binding a number
of zerocopy send requests to it and ask to complete (aka flush) it. When
flushed and all attached requests and skbs complete, it'll generate one
and only one CQE. There are intended to be passed into the network layer
as struct msghdr::msg_ubuf.

The second concept is notification slots. The userspace will be able to
register an array of slots and subsequently addressing them by the index
in the array. Slots are independent of each other. Each slot can have
only one notifier at a time (called active notifier) but many notifiers
during the lifetime. When active, a notifier not going to post any
completion but the userspace can attach requests to it by specifying
the corresponding slot while issueing send zc requests. Eventually, the
userspace will want to "flush" the notifier losing any way to attach
new requests to it, however it can use the next atomatically added
notifier of this slot or of any other slot.

When the network layer is done with all enqueued skbs attached to a
notifier and doesn't need the specified in them user data, the flushed
notifier will post a CQE.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3ecf54c31a85762bf679b0a432c9f43ecf7e61cc.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:06 -06:00
Pavel Begunkov e70cb60893 io_uring: export io_put_task()
Make io_put_task() available to non-core parts of io_uring, we'll need
it for notification infrastructure.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3686807d4c03b72e389947b0e8692d4d44334ef0.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:06 -06:00
Pavel Begunkov e02b665127 io_uring: initialise msghdr::msg_ubuf
Initialise newly added ->msg_ubuf in io_recv() and io_send().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b8f9f263875a4a36e7f26cc5d55ebe315308f57d.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:41:06 -06:00
Stefan Roesch 1c849b481b io_uring: Add tracepoint for short writes
This adds the io_uring_short_write tracepoint to io_uring. A short write
is issued if not all pages that are required for a write are in the page
cache and the async buffered writes have to return EAGAIN.

Signed-off-by: Stefan Roesch <shr@fb.com>
Link: https://lore.kernel.org/r/20220616212221.2024518-13-shr@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:32 -06:00
Jens Axboe e053aaf4da io_uring: fix issue with io_write() not always undoing sb_start_write()
This is actually an older issue, but we never used to hit the -EAGAIN
path before having done sb_start_write(). Make sure that we always call
kiocb_end_write() if we need to retry the write, so that we keep the
calls to sb_start_write() etc balanced.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:32 -06:00
Stefan Roesch 4e17aaab54 io_uring: Add support for async buffered writes
This enables the async buffered writes for the filesystems that support
async buffered writes in io-uring. Buffered writes are enabled for
blocks that are already in the page cache or can be acquired with noio.

Signed-off-by: Stefan Roesch <shr@fb.com>
Link: https://lore.kernel.org/r/20220616212221.2024518-12-shr@fb.com
[axboe: adapt to 5.20 branch]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:32 -06:00
Jens Axboe f6b543fd03 io_uring: ensure REQ_F_ISREG is set async offload
If we're offloading requests directly to io-wq because IOSQE_ASYNC was
set in the sqe, we can miss hashing writes appropriately because we
haven't set REQ_F_ISREG yet. This can cause a performance regression
with buffered writes, as io-wq then no longer correctly serializes writes
to that file.

Ensure that we set the flags in io_prep_async_work(), which will cause
the io-wq work item to be hashed appropriately.

Fixes: 584b0180f0 ("io_uring: move read/write file prep state into actual opcode handler")
Link: https://lore.kernel.org/io-uring/20220608080054.GB22428@xsang-OptiPlex-9020/
Reported-by: kernel test robot <oliver.sang@intel.com>
Tested-by: Yin Fengwei <fengwei.yin@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:18 -06:00
Jens Axboe 4f6a94d337 net: fix compat pointer in get_compat_msghdr()
A previous change enabled external users to copy the data before
calling __get_compat_msghdr(), but didn't modify get_compat_msghdr() or
__io_compat_recvmsg_copy_hdr() to take that into account. They are both
stil passing in the __user pointer rather than the copied version.

Ensure we pass in the kernel struct, not the pointer to the user data.

Link: https://lore.kernel.org/all/46439555-644d-08a1-7d66-16f8f9a320f0@samsung.com/
Fixes: 1a3e4e94a1b9 ("net: copy from user before calling __get_compat_msghdr")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:18 -06:00
Michal Koutný 4890422992 io_uring: Don't require reinitable percpu_ref
The commit 8bb649ee1d ("io_uring: remove ring quiesce for
io_uring_register") removed the worklow relying on reinit/resurrection
of the percpu_ref, hence, initialization with that requested is a relic.

This is based on code review, this causes no real bug (and theoretically
can't). Technically it's a revert of commit 214828962d ("io_uring:
initialize percpu refcounters using PERCU_REF_ALLOW_REINIT") but since
the flag omission is now justified, I'm not making this a revert.

Fixes: 8bb649ee1d ("io_uring: remove ring quiesce for io_uring_register")
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:18 -06:00
Dylan Yudaken 9b0fc3c054 io_uring: fix types in io_recvmsg_multishot_overflow
io_recvmsg_multishot_overflow had incorrect types on non x64 system.
But also it had an unnecessary INT_MAX check, which could just be done
by changing the type of the accumulator to int (also simplifying the
casts).

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: a8b38c4ce724 ("io_uring: support multishot in recvmsg")
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220715130252.610639-1-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:18 -06:00
Uros Bizjak 4ccc6db090 io_uring: Use atomic_long_try_cmpxchg in __io_account_mem
Use atomic_long_try_cmpxchg instead of
atomic_long_cmpxchg (*ptr, old, new) == old in __io_account_mem.
x86 CMPXCHG instruction returns success in ZF flag, so this
change saves a compare after cmpxchg (and related move
instruction in front of cmpxchg).

Also, atomic_long_try_cmpxchg implicitly assigns old *ptr value
to "old" when cmpxchg fails, enabling further code simplifications.

No functional change intended.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:18 -06:00
Dylan Yudaken 9bb66906f2 io_uring: support multishot in recvmsg
Similar to multishot recv, this will require provided buffers to be
used. However recvmsg is much more complex than recv as it has multiple
outputs. Specifically flags, name, and control messages.

Support this by introducing a new struct io_uring_recvmsg_out with 4
fields. namelen, controllen and flags match the similar out fields in
msghdr from standard recvmsg(2), payloadlen is the length of the payload
following the header.
This struct is placed at the start of the returned buffer. Based on what
the user specifies in struct msghdr, the next bytes of the buffer will be
name (the next msg_namelen bytes), and then control (the next
msg_controllen bytes). The payload will come at the end. The return value
in the CQE is the total used size of the provided buffer.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220714110258.1336200-4-dylany@fb.com
[axboe: style fixups, see link]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:18 -06:00
Dylan Yudaken 72c531f8ef net: copy from user before calling __get_compat_msghdr
this is in preparation for multishot receive from io_uring, where it needs
to have access to the original struct user_msghdr.

functionally this should be a no-op.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220714110258.1336200-3-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken 7fa875b8e5 net: copy from user before calling __copy_msghdr
this is in preparation for multishot receive from io_uring, where it needs
to have access to the original struct user_msghdr.

functionally this should be a no-op.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220714110258.1336200-2-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken 6d2f75a0cf io_uring: support 0 length iov in buffer select in compat
Match up work done in "io_uring: allow iov_len = 0 for recvmsg and buffer
select", but for compat code path.

Fixes: a68caad69ce5 ("io_uring: allow iov_len = 0 for recvmsg and buffer select")
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220708181838.1495428-3-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken e2df2ccb75 io_uring: fix multishot ending when not polled
If multishot is not actually polling then return IOU_OK rather than the
result.
If the result was > 0 this will confuse things further up the callstack
which expect a return <= 0.

Fixes: 1300ebb20286 ("io_uring: multishot recv")
Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220708181838.1495428-2-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Jens Axboe 43e0bbbd0b io_uring: add netmsg cache
For recvmsg/sendmsg, if they don't complete inline, we currently need
to allocate a struct io_async_msghdr for each request. This is a
somewhat large struct.

Hook up sendmsg/recvmsg to use the io_alloc_cache. This reduces the
alloc + free overhead considerably, yielding 4-5% of extra performance
running netbench.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Jens Axboe 9731bc9855 io_uring: impose max limit on apoll cache
Caches like this tend to grow to the peak size, and then never get any
smaller. Impose a max limit on the size, to prevent it from growing too
big.

A somewhat randomly chosen 512 is the max size we'll allow the cache
to get. If a batch of frees come in and would bring it over that, we
simply start kfree'ing the surplus.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Jens Axboe 9b797a37c4 io_uring: add abstraction around apoll cache
In preparation for adding limits, and one more user, abstract out the
core bits of the allocation+free cache.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Jens Axboe 9da7471ed1 io_uring: move apoll cache to poll.c
This is where it's used, move the flush handler in there.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Pavel Begunkov e8375e43ca io_uring: consolidate hash_locked io-wq handling
Don't duplicate code disabling REQ_F_HASH_LOCKED for IO_URING_F_UNLOCKED
(i.e. io-wq), move the handling into __io_arm_poll_handler().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0ff0ffdfaa65b3d536131535c3dad3c63d9b7bb0.1657203020.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Pavel Begunkov b21a51e26e io_uring: clear REQ_F_HASH_LOCKED on hash removal
Instead of clearing REQ_F_HASH_LOCKED while arming a poll, unset the bit
when we're removing the entry from the table in io_poll_tw_hash_eject().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/02e48bb88d6f1480c94ac2924c43ad1fbd48e92a.1657203020.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Pavel Begunkov ceff501790 io_uring: don't race double poll setting REQ_F_ASYNC_DATA
Just as with io_poll_double_prepare() setting REQ_F_DOUBLE_POLL, we can
race with the first poll entry when setting REQ_F_ASYNC_DATA. Move it
under io_poll_double_prepare().

Fixes: a18427bb2d9b ("io_uring: optimise submission side poll_refs")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/df6920f509c11115aa2bce8b34dc5fdb0eb98920.1657203020.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Pavel Begunkov 7a121ced6e io_uring: don't miss setting REQ_F_DOUBLE_POLL
When adding a second poll entry we should set REQ_F_DOUBLE_POLL
unconditionally. We might race with the first entry removal but that
doesn't change the rule.

Fixes: a18427bb2d9b ("io_uring: optimise submission side poll_refs")
Reported-and-tested-by: syzbot+49950ba66096b1f0209b@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8b680d83ded07424db83e8745585e7a6d72826ef.1657203020.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken cf0dd9527e io_uring: disable multishot recvmsg
recvmsg has semantics that do not make it trivial to extend to
multishot. Specifically it has user pointers and returns data in the
original parameter. In order to make this API useful these will need to be
somehow included with the provided buffers.

For now remove multishot for recvmsg as it is not useful.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220704140106.200167-1-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken e0486f3f7c io_uring: only trace one of complete or overflow
In overflow we see a duplcate line in the trace, and in some cases 3
lines (if initial io_post_aux_cqe fails).
Instead just trace once for each CQE

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220630091231.1456789-13-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken b3fdea6ecb io_uring: multishot recv
Support multishot receive for io_uring.
Typical server applications will run a loop where for each recv CQE it
requeues another recv/recvmsg.

This can be simplified by using the existing multishot functionality
combined with io_uring's provided buffers.
The API is to add the IORING_RECV_MULTISHOT flag to the SQE. CQEs will
then be posted (with IORING_CQE_F_MORE flag set) when data is available
and is read. Once an error occurs or the socket ends, the multishot will
be removed and a completion without IORING_CQE_F_MORE will be posted.

The benefit to this is that the recv is much more performant.
 * Subsequent receives are queued up straight away without requiring the
   application to finish a processing loop.
 * If there are more data in the socket (sat the provided buffer size is
   smaller than the socket buffer) then the data is immediately
   returned, improving batching.
 * Poll is only armed once and reused, saving CPU cycles

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220630091231.1456789-11-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken cbd2574854 io_uring: fix multishot accept ordering
Similar to multishot poll, drop multishot accept when CQE overflow occurs.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220630091231.1456789-10-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken a2da676376 io_uring: fix multishot poll on overflow
On overflow, multishot poll can still complete with the IORING_CQE_F_MORE
flag set.
If in the meantime the user clears a CQE and a the poll was cancelled then
the poll will post a CQE without the IORING_CQE_F_MORE (and likely result
-ECANCELED).

However when processing the application will encounter the non-overflow
CQE which indicates that there will be no more events posted. Typical
userspace applications would free memory associated with the poll in this
case.
It will then subsequently receive the earlier CQE which has overflowed,
which breaks the contract given by the IORING_CQE_F_MORE flag.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220630091231.1456789-9-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken 52120f0fad io_uring: add allow_overflow to io_post_aux_cqe
Some use cases of io_post_aux_cqe would not want to overflow as is, but
might want to change the flags/result. For example multishot receive
requires in order CQE, and so if there is an overflow it would need to
stop receiving until the overflow is taken care of.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220630091231.1456789-8-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken 114eccdf0e io_uring: add IOU_STOP_MULTISHOT return code
For multishot we want a way to signal the caller that multishot has ended
but also this might not be an error return.

For example sockets return 0 when closed, which should end a multishot
recv, but still have a CQE with result 0

Introduce IOU_STOP_MULTISHOT which does this and indicates that the return
code is stored inside req->cqe

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220630091231.1456789-7-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:17 -06:00
Dylan Yudaken 2ba69707d9 io_uring: clean up io_poll_check_events return values
The values returned are a bit confusing, where 0 and 1 have implied
meaning, so add some definitions for them.

Signed-off-by: Dylan Yudaken <dylany@fb.com>
Link: https://lore.kernel.org/r/20220630091231.1456789-6-dylany@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:16 -06:00