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>
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>
From recently io_uring provides an option to allocate a file index for
operation registering fixed files. However, it's utterly unusable with
mixed approaches when for a part of files the userspace knows better
where to place it, as it may race and users don't have any sane way to
pick a slot and hoping it will not be taken.
Let the userspace to register a range of fixed file slots in which the
auto-allocation happens. The use case is splittting the fixed table in
two parts, where on of them is used for auto-allocation and another for
slot-specified operations.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/66ab0394e436f38437cf7c44676e1920d09687ad.1656154403.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With IORING_OP_MSG_RING, one ring can send a message to another ring.
Extend that support to also allow sending a fixed file descriptor to
that ring, enabling one ring to pass a registered descriptor to another
one.
Arguments are extended to pass in:
sqe->addr3 fixed file slot in source ring
sqe->file_index fixed file slot in destination ring
IORING_OP_MSG_RING is extended to take a command argument in sqe->addr.
If set to zero (or IORING_MSG_DATA), it sends just a message like before.
If set to IORING_MSG_SEND_FD, a fixed file descriptor is sent according
to the above arguments.
Two common use cases for this are:
1) Server needs to be shutdown or restarted, pass file descriptors to
another onei
2) Backend is split, and one accepts connections, while others then get
the fd passed and handle the actual connection.
Both of those are classic SCM_RIGHTS use cases, and it's not possible to
support them with direct descriptors today.
By default, this will post a CQE to the target ring, similarly to how
IORING_MSG_DATA does it. If IORING_MSG_RING_CQE_SKIP is set, no message
is posted to the target ring. The issuer is expected to notify the
receiver side separately.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The io_uring cancelation API is async, like any other API that we expose
there. For the case of finding a request to cancel, or not finding one,
it is fully sync in that when submission returns, the CQE for both the
cancelation request and the targeted request have been posted to the
CQ ring.
However, if the targeted work is being executed by io-wq, the API can
only start the act of canceling it. This makes it difficult to use in
some circumstances, as the caller then has to wait for the CQEs to come
in and match on the same cancelation data there.
Provide a IORING_REGISTER_SYNC_CANCEL command for io_uring_register()
that does sync cancelations, always. For the io-wq case, it'll wait
for the cancelation to come in before returning. The only expected
returns from this API is:
0 Request found and canceled fine.
> 0 Requests found and canceled. Only happens if asked to
cancel multiple requests, and if the work wasn't in
progress.
-ENOENT Request not found.
-ETIME A timeout on the operation was requested, but the timeout
expired before we could cancel.
and we won't get -EALREADY via this API.
If the timeout value passed in is -1 (tv_sec and tv_nsec), then that
means that no timeout is requested. Otherwise, the timespec passed in
is the amount of time the sync cancel will wait for a successful
cancelation.
Link: https://github.com/axboe/liburing/discussions/608
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation for not having a request to pass in that carries this
state, add a separate cancelation flag that allows the caller to ask
for a fixed file for cancelation.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
By default, the POLL_ADD command does edge triggered poll - if we get
a non-zero mask on the initial poll attempt, we complete the request
successfully.
Support level triggered by always waiting for a notification, regardless
of whether or not the initial mask matches the file state.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull kvm fixes from Paolo Bonzini:
- Check for invalid flags to KVM_CAP_X86_USER_SPACE_MSR
- Fix use of sched_setaffinity in selftests
- Sync kernel headers to tools
- Fix KVM_STATS_UNIT_MAX
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: Protect the unused bits in MSR exiting flags
tools headers UAPI: Sync linux/kvm.h with the kernel sources
KVM: selftests: Fix target thread to be migrated in rseq_test
KVM: stats: Fix value for KVM_STATS_UNIT_MAX for boolean stats
commit 1b870fa557 ("kvm: stats: tell userspace which values are
boolean") added a new stat unit (boolean) but failed to raise
KVM_STATS_UNIT_MAX.
Fix by pointing UNIT_MAX at the new max value of UNIT_BOOLEAN.
Fixes: 1b870fa557 ("kvm: stats: tell userspace which values are boolean")
Reported-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20220719125229.2934273-1-oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull input fixes from Dmitry Torokhov:
- fix Goodix driver to properly behave on the Aya Neo Next
- some more sanity checks in usbtouchscreen driver
- a tweak in wm97xx driver in preparation for remove() to return void
- a clarification in input core regarding units of measurement for
resolution on touch events.
* tag 'input-for-v5.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: document the units for resolution of size axes
Input: goodix - call acpi_device_fix_up_power() in some cases
Input: wm97xx - make .remove() obviously always return 0
Input: usbtouchscreen - add driver_info sanity check
Pull tty and serial driver fixes from Greg KH:
"Here are some TTY and Serial driver fixes for 5.19-rc7. They resolve a
number of reported problems including:
- longtime bug in pty_write() that has been reported in the past.
- 8250 driver fixes
- new serial device ids
- vt overlapping data copy bugfix
- other tiny serial driver bugfixes
All of these have been in linux-next for a while with no reported
problems"
* tag 'tty-5.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: use new tty_insert_flip_string_and_push_buffer() in pty_write()
tty: extract tty_flip_buffer_commit() from tty_flip_buffer_push()
serial: 8250: dw: Fix the macro RZN1_UART_xDMACR_8_WORD_BURST
vt: fix memory overlapping when deleting chars in the buffer
serial: mvebu-uart: correctly report configured baudrate value
serial: 8250: Fix PM usage_count for console handover
serial: 8250: fix return error code in serial8250_request_std_resource()
serial: stm32: Clear prev values before setting RTS delays
tty: Add N_CAN327 line discipline ID for ELM327 based CAN driver
serial: 8250: Fix __stop_tx() & DMA Tx restart races
serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle
tty: serial: samsung_tty: set dma burst_size to 1
serial: 8250: dw: enable using pdata with ACPI
Pull KVM fixes from Paolo Bonzini:
"RISC-V:
- Fix missing PAGE_PFN_MASK
- Fix SRCU deadlock caused by kvm_riscv_check_vcpu_requests()
x86:
- Fix for nested virtualization when TSC scaling is active
- Estimate the size of fastcc subroutines conservatively, avoiding
disastrous underestimation when return thunks are enabled
- Avoid possible use of uninitialized fields of 'struct
kvm_lapic_irq'
Generic:
- Mark as such the boolean values available from the statistics file
descriptors
- Clarify statistics documentation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: emulate: do not adjust size of fastop and setcc subroutines
KVM: x86: Fully initialize 'struct kvm_lapic_irq' in kvm_pv_kick_cpu_op()
Documentation: kvm: clarify histogram units
kvm: stats: tell userspace which values are boolean
x86/kvm: fix FASTOP_SIZE when return thunks are enabled
KVM: nVMX: Always enable TSC scaling for L2 when it was enabled for L1
RISC-V: KVM: Fix SRCU deadlock caused by kvm_riscv_check_vcpu_requests()
riscv: Fix missing PAGE_PFN_MASK
Pull networking fixes from Jakub Kicinski:
"Including fixes from netfilter, bpf and wireless.
Still no major regressions, the release continues to be calm. An
uptick of fixes this time around due to trivial data race fixes and
patches flowing down from subtrees.
There has been a few driver fixes (particularly a few fixes for false
positives due to 66e4c8d950 which went into -next in May!) that make
me worry the wide testing is not exactly fully through.
So "calm" but not "let's just cut the final ASAP" vibes over here.
Current release - regressions:
- wifi: rtw88: fix write to const table of channel parameters
Current release - new code bugs:
- mac80211: add gfp_t arg to ieeee80211_obss_color_collision_notify
- mlx5:
- TC, allow offload from uplink to other PF's VF
- Lag, decouple FDB selection and shared FDB
- Lag, correct get the port select mode str
- bnxt_en: fix and simplify XDP transmit path
- r8152: fix accessing unset transport header
Previous releases - regressions:
- conntrack: fix crash due to confirmed bit load reordering (after
atomic -> refcount conversion)
- stmmac: dwc-qos: disable split header for Tegra194
Previous releases - always broken:
- mlx5e: ring the TX doorbell on DMA errors
- bpf: make sure mac_header was set before using it
- mac80211: do not wake queues on a vif that is being stopped
- mac80211: fix queue selection for mesh/OCB interfaces
- ip: fix dflt addr selection for connected nexthop
- seg6: fix skb checksums for SRH encapsulation/insertion
- xdp: fix spurious packet loss in generic XDP TX path
- bunch of sysctl data race fixes
- nf_log: incorrect offset to network header
Misc:
- bpf: add flags arg to bpf_dynptr_read and bpf_dynptr_write APIs"
* tag 'net-5.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (87 commits)
nfp: flower: configure tunnel neighbour on cmsg rx
net/tls: Check for errors in tls_device_init
MAINTAINERS: Add an additional maintainer to the AMD XGBE driver
xen/netback: avoid entering xenvif_rx_next_skb() with an empty rx queue
selftests/net: test nexthop without gw
ip: fix dflt addr selection for connected nexthop
net: atlantic: remove aq_nic_deinit() when resume
net: atlantic: remove deep parameter on suspend/resume functions
sfc: fix kernel panic when creating VF
seg6: bpf: fix skb checksum in bpf_push_seg6_encap()
seg6: fix skb checksum in SRv6 End.B6 and End.B6.Encaps behaviors
seg6: fix skb checksum evaluation in SRH encapsulation/insertion
sfc: fix use after free when disabling sriov
net: sunhme: output link status with a single print.
r8152: fix accessing unset transport header
net: stmmac: fix leaks in probe
net: ftgmac100: Hold reference returned by of_get_child_by_name()
nexthop: Fix data-races around nexthop_compat_mode.
ipv4: Fix data-races around sysctl_ip_dynaddr.
tcp: Fix a data-race around sysctl_tcp_ecn_fallback.
...
Some of the statistics values exported by KVM are always only 0 or 1.
It can be useful to export this fact to userspace so that it can track
them specially (for example by polling the value every now and then to
compute a % of time spent in a specific state).
Therefore, add "boolean value" as a new "unit". While it is not exactly
a unit, it walks and quacks like one. In particular, using the type
would be wrong because boolean values could be instantaneous or peak
values (e.g. "is the rmap allocated?") or even two-bucket histograms
(e.g. "number of posted vs. non-posted interrupt injections").
Suggested-by: Amneesh Singh <natto@weirdnatto.in>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Today, the resolution of size axes is not documented. As a result, it's
not clear what the canonical interpretation of this value should be. On
Android, there is a need to calculate the size of the touch ellipse in
physical units (millimeters).
After reviewing linux source, it turned out that most of the existing
usages are already interpreting this value as "units/mm". This
documentation will make it explicit. This will help device
implementations with correctly following the linux specs, and will
ensure that the devices will work on Android without needing further
customized parameters for scaling of major/minor values.
Signed-off-by: Siarhei Vishniakou <svv@google.com>
Reviewed-by: Jeff LaBundy <jeff@labundy.com>
Link: https://lore.kernel.org/r/20220520084514.3451193-1-svv@google.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Daniel Borkmann says:
====================
bpf 2022-07-08
We've added 3 non-merge commits during the last 2 day(s) which contain
a total of 7 files changed, 40 insertions(+), 24 deletions(-).
The main changes are:
1) Fix cBPF splat triggered by skb not having a mac header, from Eric Dumazet.
2) Fix spurious packet loss in generic XDP when pushing packets out (note
that native XDP is not affected by the issue), from Johan Almbladh.
3) Fix bpf_dynptr_{read,write}() helper signatures with flag argument before
its set in stone as UAPI, from Joanne Koong.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Add flags arg to bpf_dynptr_read and bpf_dynptr_write APIs
bpf: Make sure mac_header was set before using it
xdp: Fix spurious packet loss in generic XDP TX path
====================
Link: https://lore.kernel.org/r/20220708213418.19626-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull io_uring tweak from Jens Axboe:
"Just a minor tweak to an addition made in this release cycle: padding
a 32-bit value that's in a 64-bit union to avoid any potential
funkiness from that"
* tag 'io_uring-5.19-2022-07-08' of git://git.kernel.dk/linux-block:
io_uring: explicit sqe padding for ioctl commands
Commit 13bbbfbea7 ("bpf: Add bpf_dynptr_read and bpf_dynptr_write")
added the bpf_dynptr_write() and bpf_dynptr_read() APIs.
However, it will be needed for some dynptr types to pass in flags as
well (e.g. when writing to a skb, the user may like to invalidate the
hash or recompute the checksum).
This patch adds a "u64 flags" arg to the bpf_dynptr_read() and
bpf_dynptr_write() APIs before their UAPI signature freezes where
we then cannot change them anymore with a 5.19.x released kernel.
Fixes: 13bbbfbea7 ("bpf: Add bpf_dynptr_read and bpf_dynptr_write")
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20220706232547.4016651-1-joannelkoong@gmail.com
Pull io_uring fixes from Jens Axboe:
"Two minor tweaks:
- While we still can, adjust the send/recv based flags to be in
->ioprio rather than in ->addr2. This is consistent with eg accept,
and also doesn't waste a full 64-bit field for flags (Pavel)
- 5.18-stable fix for re-importing provided buffers. Not much real
world relevance here as it'll only impact non-pollable files gone
async, which is more of a practical test case rather than something
that is used in the wild (Dylan)"
* tag 'io_uring-5.19-2022-07-01' of git://git.kernel.dk/linux-block:
io_uring: fix provided buffer import
io_uring: keep sendrecv flags in ioprio
We waste a u64 SQE field for flags even though we don't need as many
bits and it can be used for something more useful later. Store io_uring
specific send/recv flags in sqe->ioprio instead of ->addr2.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Fixes: 0455d4ccec ("io_uring: add POLL_FIRST support for send/sendmsg and recv/recvmsg")
[axboe: change comment in io_uring.h as well]
Signed-off-by: Jens Axboe <axboe@kernel.dk>