Commit Graph

9807 Commits

Author SHA1 Message Date
Hao Luo
4976b718c3 bpf: Introduce pseudo_btf_id
Pseudo_btf_id is a type of ld_imm insn that associates a btf_id to a
ksym so that further dereferences on the ksym can use the BTF info
to validate accesses. Internally, when seeing a pseudo_btf_id ld insn,
the verifier reads the btf_id stored in the insn[0]'s imm field and
marks the dst_reg as PTR_TO_BTF_ID. The btf_id points to a VAR_KIND,
which is encoded in btf_vminux by pahole. If the VAR is not of a struct
type, the dst reg will be marked as PTR_TO_MEM instead of PTR_TO_BTF_ID
and the mem_size is resolved to the size of the VAR's type.

>From the VAR btf_id, the verifier can also read the address of the
ksym's corresponding kernel var from kallsyms and use that to fill
dst_reg.

Therefore, the proper functionality of pseudo_btf_id depends on (1)
kallsyms and (2) the encoding of kernel global VARs in pahole, which
should be available since pahole v1.18.

Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200929235049.2533242-2-haoluo@google.com
2020-10-02 14:59:25 -07:00
Chuck Lever
ba1df797e5 NFSACL: Replace PROC() macro with open code
Clean up: Follow-up on ten-year-old commit b9081d90f5 ("NFS: kill
off complicated macro 'PROC'") by performing the same conversion in
the NFSACL code. To reduce the chance of error, I copied the original
C preprocessor output and then made some minor edits.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-10-02 09:37:41 -04:00
Avihai Horon
9f85cbe50a RDMA/uverbs: Expose the new GID query API to user space
Expose the query GID table and entry API to user space by adding two new
methods and method handlers to the device object.

This API provides a faster way to query a GID table using single call and
will be used in libibverbs to improve current approach that requires
multiple calls to open, close and read multiple sysfs files for a single
GID table entry.

Link: https://lore.kernel.org/r/20200923165015.2491894-5-leon@kernel.org
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-10-01 21:20:11 -03:00
Avihai Horon
c4b4d548fa RDMA/core: Introduce new GID table query API
Introduce rdma_query_gid_table which enables querying all the GID tables
of a given device and copying the attributes of all valid GID entries to a
provided buffer.

This API provides a faster way to query a GID table using single call and
will be used in libibverbs to improve current approach that requires
multiple calls to open, close and read multiple sysfs files for a single
GID table entry.

Link: https://lore.kernel.org/r/20200923165015.2491894-4-leon@kernel.org
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-10-01 21:20:11 -03:00
David S. Miller
23a1f682a9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2020-10-01

The following pull-request contains BPF updates for your *net-next* tree.

We've added 90 non-merge commits during the last 8 day(s) which contain
a total of 103 files changed, 7662 insertions(+), 1894 deletions(-).

Note that once bpf(/net) tree gets merged into net-next, there will be a small
merge conflict in tools/lib/bpf/btf.c between commit 1245008122 ("libbpf: Fix
native endian assumption when parsing BTF") from the bpf tree and the commit
3289959b97 ("libbpf: Support BTF loading and raw data output in both endianness")
from the bpf-next tree. Correct resolution would be to stick with bpf-next, it
should look like:

  [...]
        /* check BTF magic */
        if (fread(&magic, 1, sizeof(magic), f) < sizeof(magic)) {
                err = -EIO;
                goto err_out;
        }
        if (magic != BTF_MAGIC && magic != bswap_16(BTF_MAGIC)) {
                /* definitely not a raw BTF */
                err = -EPROTO;
                goto err_out;
        }

        /* get file size */
  [...]

The main changes are:

1) Add bpf_snprintf_btf() and bpf_seq_printf_btf() helpers to support displaying
   BTF-based kernel data structures out of BPF programs, from Alan Maguire.

2) Speed up RCU tasks trace grace periods by a factor of 50 & fix a few race
   conditions exposed by it. It was discussed to take these via BPF and
   networking tree to get better testing exposure, from Paul E. McKenney.

3) Support multi-attach for freplace programs, needed for incremental attachment
   of multiple XDP progs using libxdp dispatcher model, from Toke Høiland-Jørgensen.

4) libbpf support for appending new BTF types at the end of BTF object, allowing
   intrusive changes of prog's BTF (useful for future linking), from Andrii Nakryiko.

5) Several BPF helper improvements e.g. avoid atomic op in cookie generator and add
   a redirect helper into neighboring subsys, from Daniel Borkmann.

6) Allow map updates on sockmaps from bpf_iter context in order to migrate sockmaps
   from one to another, from Lorenz Bauer.

7) Fix 32 bit to 64 bit assignment from latest alu32 bounds tracking which caused
   a verifier issue due to type downgrade to scalar, from John Fastabend.

8) Follow-up on tail-call support in BPF subprogs which optimizes x64 JIT prologue
   and epilogue sections, from Maciej Fijalkowski.

9) Add an option to perf RB map to improve sharing of event entries by avoiding remove-
   on-close behavior. Also, add BPF_PROG_TEST_RUN for raw_tracepoint, from Song Liu.

10) Fix a crash in AF_XDP's socket_release when memory allocation for UMEMs fails,
    from Magnus Karlsson.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-01 14:29:01 -07:00
Yishai Hadas
677cf51f71 RDMA/mlx5: Extend advice MR to support non faulting mode
Extend advice MR to support non faulting mode, this can improve
performance by increasing the populated page tables in the device.

Link: https://lore.kernel.org/r/20200930163828.1336747-4-leon@kernel.org
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-10-01 16:44:05 -03:00
Mike Snitzer
61931c0ee9 dm: export dm_copy_name_and_uuid
Allow DM targets to access the configured name and uuid.
Also, bump DM ioctl version.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-10-01 15:03:40 -04:00
Jacob Pan
6278eecba3 iommu/vt-d: Check UAPI data processed by IOMMU core
IOMMU generic layer already does sanity checks on UAPI data for version
match and argsz range based on generic information.

This patch adjusts the following data checking responsibilities:
- removes the redundant version check from VT-d driver
- removes the check for vendor specific data size
- adds check for the use of reserved/undefined flags

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/1601051567-54787-7-git-send-email-jacob.jun.pan@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-10-01 14:52:46 +02:00
Jacob Pan
d90573812e iommu/uapi: Handle data and argsz filled by users
IOMMU user APIs are responsible for processing user data. This patch
changes the interface such that user pointers can be passed into IOMMU
code directly. Separate kernel APIs without user pointers are introduced
for in-kernel users of the UAPI functionality.

IOMMU UAPI data has a user filled argsz field which indicates the data
length of the structure. User data is not trusted, argsz must be
validated based on the current kernel data size, mandatory data size,
and feature flags.

User data may also be extended, resulting in possible argsz increase.
Backward compatibility is ensured based on size and flags (or
the functional equivalent fields) checking.

This patch adds sanity checks in the IOMMU layer. In addition to argsz,
reserved/unused fields in padding, flags, and version are also checked.
Details are documented in Documentation/userspace-api/iommu.rst

Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/1601051567-54787-6-git-send-email-jacob.jun.pan@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-10-01 14:52:46 +02:00
Jacob Pan
8d3bb3b8cb iommu/uapi: Use named union for user data
IOMMU UAPI data size is filled by the user space which must be validated
by the kernel. To ensure backward compatibility, user data can only be
extended by either re-purpose padding bytes or extend the variable sized
union at the end. No size change is allowed before the union. Therefore,
the minimum size is the offset of the union.

To use offsetof() on the union, we must make it named.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/linux-iommu/20200611145518.0c2817d6@x1.home/
Link: https://lore.kernel.org/r/1601051567-54787-4-git-send-email-jacob.jun.pan@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-10-01 14:52:46 +02:00
Jacob Pan
1e6aaae93e iommu/uapi: Add argsz for user filled data
As IOMMU UAPI gets extended, user data size may increase. To support
backward compatibiliy, this patch introduces a size field to each UAPI
data structures. It is *always* the responsibility for the user to fill in
the correct size. Padding fields are adjusted to ensure 8 byte alignment.

Specific scenarios for user data handling are documented in:
Documentation/userspace-api/iommu.rst

As there is no current users of the API, struct version is not
incremented.

Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/1601051567-54787-3-git-send-email-jacob.jun.pan@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2020-10-01 14:52:46 +02:00
Song Liu
792caccc45 bpf: Introduce BPF_F_PRESERVE_ELEMS for perf event array
Currently, perf event in perf event array is removed from the array when
the map fd used to add the event is closed. This behavior makes it
difficult to the share perf events with perf event array.

Introduce perf event map that keeps the perf event open with a new flag
BPF_F_PRESERVE_ELEMS. With this flag set, perf events in the array are not
removed when the original map fd is closed. Instead, the perf event will
stay in the map until 1) it is explicitly removed from the array; or 2)
the array is freed.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200930224927.1936644-2-songliubraving@fb.com
2020-09-30 23:18:12 -07:00
Jens Axboe
9055420072 io_uring: provide IORING_ENTER_SQ_WAIT for SQPOLL SQ ring waits
When using SQPOLL, applications can run into the issue of running out of
SQ ring entries because the thread hasn't consumed them yet. The only
option for dealing with that is checking later, or busy checking for the
condition.

Provide IORING_ENTER_SQ_WAIT if applications want to wait on this
condition.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:32:33 -06:00
Stefano Garzarella
7e84e1c756 io_uring: allow disabling rings during the creation
This patch adds a new IORING_SETUP_R_DISABLED flag to start the
rings disabled, allowing the user to register restrictions,
buffers, files, before to start processing SQEs.

When IORING_SETUP_R_DISABLED is set, SQE are not processed and
SQPOLL kthread is not started.

The restrictions registration are allowed only when the rings
are disable to prevent concurrency issue while processing SQEs.

The rings can be enabled using IORING_REGISTER_ENABLE_RINGS
opcode with io_uring_register(2).

Suggested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:32:33 -06:00
Stefano Garzarella
21b55dbc06 io_uring: add IOURING_REGISTER_RESTRICTIONS opcode
The new io_uring_register(2) IOURING_REGISTER_RESTRICTIONS opcode
permanently installs a feature allowlist on an io_ring_ctx.
The io_ring_ctx can then be passed to untrusted code with the
knowledge that only operations present in the allowlist can be
executed.

The allowlist approach ensures that new features added to io_uring
do not accidentally become available when an existing application
is launched on a newer kernel version.

Currently is it possible to restrict sqe opcodes, sqe flags, and
register opcodes.

IOURING_REGISTER_RESTRICTIONS can only be made once. Afterwards
it is not possible to change restrictions anymore.
This prevents untrusted code from removing restrictions.

Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:32:33 -06:00
Stefano Garzarella
9d4a75efa2 io_uring: use an enumeration for io_uring_register(2) opcodes
The enumeration allows us to keep track of the last
io_uring_register(2) opcode available.

Behaviour and opcodes names don't change.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-30 20:32:33 -06:00
Daniel Borkmann
b4ab314149 bpf: Add redirect_neigh helper as redirect drop-in
Add a redirect_neigh() helper as redirect() drop-in replacement
for the xmit side. Main idea for the helper is to be very similar
in semantics to the latter just that the skb gets injected into
the neighboring subsystem in order to let the stack do the work
it knows best anyway to populate the L2 addresses of the packet
and then hand over to dev_queue_xmit() as redirect() does.

This solves two bigger items: i) skbs don't need to go up to the
stack on the host facing veth ingress side for traffic egressing
the container to achieve the same for populating L2 which also
has the huge advantage that ii) the skb->sk won't get orphaned in
ip_rcv_core() when entering the IP routing layer on the host stack.

Given that skb->sk neither gets orphaned when crossing the netns
as per 9c4c325252 ("skbuff: preserve sock reference when scrubbing
the skb.") the helper can then push the skbs directly to the phys
device where FQ scheduler can do its work and TCP stack gets proper
backpressure given we hold on to skb->sk as long as skb is still
residing in queues.

With the helper used in BPF data path to then push the skb to the
phys device, I observed a stable/consistent TCP_STREAM improvement
on veth devices for traffic going container -> host -> host ->
container from ~10Gbps to ~15Gbps for a single stream in my test
environment.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: David Ahern <dsahern@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Cc: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/bpf/f207de81629e1724899b73b8112e0013be782d35.1601477936.git.daniel@iogearbox.net
2020-09-30 11:50:35 -07:00
Daniel Borkmann
b426ce83ba bpf: Add classid helper only based on skb->sk
Similarly to 5a52ae4e32 ("bpf: Allow to retrieve cgroup v1 classid
from v2 hooks"), add a helper to retrieve cgroup v1 classid solely
based on the skb->sk, so it can be used as key as part of BPF map
lookups out of tc from host ns, in particular given the skb->sk is
retained these days when crossing net ns thanks to 9c4c325252
("skbuff: preserve sock reference when scrubbing the skb."). This
is similar to bpf_skb_cgroup_id() which implements the same for v2.
Kubernetes ecosystem is still operating on v1 however, hence net_cls
needs to be used there until this can be dropped in with the v2
helper of bpf_skb_cgroup_id().

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/ed633cf27a1c620e901c5aa99ebdefb028dce600.1601477936.git.daniel@iogearbox.net
2020-09-30 11:50:34 -07:00
Jose M. Guisado Gomez
002f217653 netfilter: nf_tables: add userdata attributes to nft_chain
Enables storing userdata for nft_chain. Field udata points to user data
and udlen stores its length.

Adds new attribute flag NFTA_CHAIN_USERDATA.

Signed-off-by: Jose M. Guisado Gomez <guigom@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-09-30 11:46:50 +02:00
Kent Gibson
b234d233fe gpio: uapi: document uAPI v1 as deprecated
Update uAPI documentation to deprecate v1 structs and ioctls.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-09-30 10:57:08 +02:00
Kent Gibson
b53911aa87 gpio: uapi: define uAPI v2
Add a new version of the uAPI to address existing 32/64-bit alignment
issues, add support for debounce and event sequence numbers, allow
requested lines with different configurations, and provide some future
proofing by adding padding reserved for future use.

The alignment issue relates to the gpioevent_data, which packs to different
sizes on 32-bit and 64-bit platforms. That creates problems for 32-bit apps
running on 64-bit kernels.  uAPI v2 addresses that particular issue, and
the problem more generally, by adding pad fields that explicitly pad
structs out to 64-bit boundaries, so they will pack to the same size now,
and even if some of the reserved padding is used for __u64 fields in the
future.

The new structs have been analysed with pahole to ensure that they
are sized as expected and contain no implicit padding.

The lack of future proofing in v1 makes it impossible to, for example,
add the debounce feature that is included in v2.
The future proofing is addressed by providing configurable attributes in
line config and reserved padding in all structs for future features.
Specifically, the line request, config, info, info_changed and event
structs receive updated versions and new ioctls.

As the majority of the structs and ioctls were being replaced, it is
opportune to rework some of the other aspects of the uAPI:

v1 has three different flags fields, each with their own separate
bit definitions.  In v2 that is collapsed to one - gpio_v2_line_flag.

The handle and event requests are merged into a single request, the line
request, as the two requests were mostly the same other than the edge
detection provided by event requests.  As a byproduct, the v2 uAPI allows
for multiple lines producing edge events on the same line handle.
This is a new capability as v1 only supports a single line in an event
request.

As a consequence, there are now only two types of file handle to be
concerned with, the chip and the line, and it is clearer which ioctls
apply to which type of handle.

There is also some minor renaming of fields for consistency compared to
their v1 counterparts, e.g. offset rather than lineoffset or line_offset,
and consumer rather than consumer_label.

Additionally, v1 GPIOHANDLES_MAX becomes GPIO_V2_LINES_MAX in v2 for
clarity, and the gpiohandle_data __u8 array becomes a bitmap in
gpio_v2_line_values.

The v2 uAPI is mostly a reorganisation and extension of v1, so userspace
code, particularly libgpiod, should readily port to it.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-09-30 10:56:38 +02:00
Kent Gibson
539430fbbc gpio: uapi: define GPIO_MAX_NAME_SIZE for array sizes
Replace constant array sizes with a macro constant to clarify the source
of array sizes, provide a place to document any constraints on the size,
and to simplify array sizing in userspace if constructing structs
from their composite fields.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-09-30 10:56:34 +02:00
Alistair Delva
91e515c2f0 virtio-gpu api: fix 64/32 compat issue with blob implementation
We encountered this issue when booting blob with a 32-bit kernel.
The implementation doesn't match v6 of the virtio-spec change, so fix
this.

Fixes: ff886cbdcc ("virtio-gpu api: blob resources")
Signed-off-by: Alistair Delva <adelva@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200929215333.1241-1-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2020-09-30 08:31:08 +02:00
Jacob Keller
2ec13cbcfa devlink: include <linux/const.h> for _BITUL
Commit 5d5b4128c4 ("devlink: introduce flash update overwrite mask")
added a usage of _BITUL to the UAPI <linux/devlink.h> header, but failed
to include the header file where it was defined. It happens that this
does not break any existing kernel include chains because it gets
included through other sources. However, when including the UAPI headers
in a userspace application (such as devlink in iproute2), _BITUL is not
defined.

Fixes: 5d5b4128c4 ("devlink: introduce flash update overwrite mask")
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-29 13:58:41 -07:00
Mike Snitzer
1471308fb5 Merge remote-tracking branch 'jens/for-5.10/block' into dm-5.10
DM depends on these block 5.10 commits:

22ada802ed block: use lcm_not_zero() when stacking chunk_sectors
07d098e6bb block: allow 'chunk_sectors' to be non-power-of-2
021a24460d block: add QUEUE_FLAG_NOWAIT
6abc49468e dm: add support for REQ_NOWAIT and enable it for linear target

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-09-29 16:31:35 -04:00
Tom Parkin
3f47cb4c1c l2tp: report rx cookie discards in netlink get
When an L2TPv3 session receives a data frame with an incorrect cookie
l2tp_core logs a warning message and bumps a stats counter to reflect
the fact that the packet has been dropped.

However, the stats counter in question is missing from the l2tp_netlink
get message for tunnel and session instances.

Include the statistic in the netlink get response.

Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-29 13:26:36 -07:00
Toke Høiland-Jørgensen
4a1e7c0c63 bpf: Support attaching freplace programs to multiple attach points
This enables support for attaching freplace programs to multiple attach
points. It does this by amending the UAPI for bpf_link_Create with a target
btf ID that can be used to supply the new attachment point along with the
target program fd. The target must be compatible with the target that was
supplied at program load time.

The implementation reuses the checks that were factored out of
check_attach_btf_id() to ensure compatibility between the BTF types of the
old and new attachment. If these match, a new bpf_tracing_link will be
created for the new attach target, allowing multiple attachments to
co-exist simultaneously.

The code could theoretically support multiple-attach of other types of
tracing programs as well, but since I don't have a use case for any of
those, there is no API support for doing so.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355169.48470.17165680973640685368.stgit@toke.dk
2020-09-29 13:09:24 -07:00
Krzysztof Wilczyński
3789af9a13 PCI/PM: Rename pci_dev.d3_delay to d3hot_delay
PCI devices support two variants of the D3 power state: D3hot (main power
present) D3cold (main power removed).  Previously struct pci_dev contained:

  unsigned int    d3_delay;       /* D3->D0 transition time in ms */
  unsigned int    d3cold_delay;   /* D3cold->D0 transition time in ms */

"d3_delay" refers specifically to the D3hot state.  Rename it to
"d3hot_delay" to avoid ambiguity and align with the ACPI "_DSM for
Specifying Device Readiness Durations" in the PCI Firmware spec r3.2,
sec 4.6.9.

There is no change to the functionality.

Link: https://lore.kernel.org/r/20200730210848.1578826-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-09-29 14:21:50 -05:00
Gurchetan Singh
bf36dea176 drm/virtgpu api: cross-device feature
This feature was recently added to virtio-gpu, lets make
it userspace queryable. It's an error to use
BLOB_FLAG_USE_CROSS_DEVICE when this feature is not present.

Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-7-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2020-09-29 11:23:18 +02:00
Gurchetan Singh
7a571c76dd drm/virtgpu api: host visible feature
This exposes the host visible feature to userspace.  Without it,
it is an error to specify BLOB_MEM_HOST3D with
BLOG_FLAG_USE_MAPPABLE.

Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-6-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2020-09-29 11:23:14 +02:00
Gurchetan Singh
eda3e1018f drm/virtgpu api: blob resources
This makes blob resources available to guest userspace. They are needed
for GL4.5, Vulkan and zero-copy virtio-gpu.

For Mesa, blob resources have been tested with Piglit's ARB_buffer_storage
tests and apitraces.  Apitraces of GL4.5 games show we're between 70%
to 80% of host performance on Iris, based on a apitrace of a 2013 GL4.5
game:

11.204 FPS (guest)
15.947 FPS (host)

This is still better than the status quo, when said game was unplayable
with Virgl due to an inefficient GL4.3 fallback.  But there's still room
for improvement if we want to match HW-assisted virtualization.

For Vulkan, blob resources have been tested with dEQP.vk.memory* and
running Vulkan applications in production with the "Cuttlefish" virtual
Android device.  This has been done with Lingfeng Yang's "gfxstream"
Vulkan implementation, which virtualizes Vulkan across many Google
products.

Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Chia-I Wu <olvaffe@gmail.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-5-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2020-09-29 11:23:08 +02:00
Gerd Hoffmann
e5cd6cbe02 virtio-gpu api: host visible feature
This patch adds a new virtgpu feature that allows directly
mapping host allocated resources.

This is based on virtio shared memory regions, which allows
querying for memory regions using PCI transport. Each shared
memory region has an associated "shmid", the meaning of which
is device specific.

For virtio-gpu, we can define the shared memory region with id
VIRTIO_GPU_SHM_ID_HOST_VISIBLE to be the "host visible memory
region".

The presence of the host visible memory region means the following
hypercalls are supported:

1) VIRTIO_GPU_CMD_RESOURCE_MAP_BLOB

This hypercall tells the host to inject the host resource's
mapping in an offset into virtio-gpu's PCI address space.
This is typically done via KVM_SET_USER_MEMORY_REGION on Linux
hosts.

On success, VIRTIO_GPU_RESP_OK_MAP_INFO is returned, which
specifies the host buffer's caching type and possibly in the
future performance hints about the buffer..

2) VIRTIO_GPU_CMD_RESOURCE_UNMAP_BLOB

This hypercall tells the host to remove the host resource's
mapping from the guest VM.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-4-gurchetansingh@chromium.org
Co-developed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
2020-09-29 11:23:00 +02:00
Gerd Hoffmann
ff886cbdcc virtio-gpu api: blob resources
A blob resource is a container for:
   - VIRTIO_GPU_BLOB_MEM_GUEST: a guest memory allocation
     (referred to as a "guest-only blob resource")

   - VIRTIO_GPU_BLOB_MEM_HOST3D: a host3d memory allocation
     (referred to as a "host-only blob resource")

   - VIRTIO_GPU_BLOB_MEM_HOST3D_GUEST: a guest + host3d memory allocation
     (referred to as a "default blob resource").

The memory properties of the blob resource must be described by
`blob_mem`.

For default and guest only blob resources set, `nents` guest system
pages are assigned to the resource.  For default blob resources,
these guest pages are used for transfer operations. Attach/detach is
also possible to allow swap-in/swap-out, but isn't required since it
may not be applicable to future blob mem types
(shared guest/guest vram).

Host allocations depend on whether the 3D is supported. If 3D is not
supported, the only valid field for `blob_mem` is
VIRTIO_GPU_BLOB_MEM_GUEST.

If 3D is supported, the virtio-gpu resource is created from the
context local object identified by the `blob_id`. The actual host
allocation done by the CMD_SUBMIT_3D.

Userspace must specify if the blob resource is intended to be used
for userspace mapping, sharing between virtio-gpu contexts and/or
sharing between virtio devices. This is done via `blob_flags`.

For 3D hosts, both VIRTIO_GPU_CMD_TRANSFER_TO_HOST_3D and
VIRTIO_GPU_CMD_TRANSFER_FROM_HOST_3D may be used to update
the host resource. There is no restriction on the image/buffer
view the guest/host userspace has on the blob resource.

VIRTIO_GPU_CMD_SET_SCANOUT_BLOB / VIRTIO_GPU_CMD_RESOURCE_FLUSH may
be used with blob resources as well.  The modifier is intentionally
left out of SCANOUT_BLOB, and auxilary blobs are also left out
as a simplification.

The use case for blob resources is zero-copy, needed for coherent
memory in virglrenderer. Host only blob resources are not mappable
without the feature described in the next patch, but are shareable.

Future work:
   - Emulated coherent `blob_mem` type for QEMU/vhost-user
   - A `blob_mem` type for guest-only resources imported in
     cache-coherent FOSS GPU/display drivers.
   - Display integration involving the blob model using seamless
     Wayland windows.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Chia-I Wu <olvaffe@gmail.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-3-gurchetansingh@chromium.org
Co-developed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
2020-09-29 11:22:49 +02:00
Alan Maguire
eb411377ae bpf: Add bpf_seq_printf_btf helper
A helper is added to allow seq file writing of kernel data
structures using vmlinux BTF.  Its signature is

long bpf_seq_printf_btf(struct seq_file *m, struct btf_ptr *ptr,
                        u32 btf_ptr_size, u64 flags);

Flags and struct btf_ptr definitions/use are identical to the
bpf_snprintf_btf helper, and the helper returns 0 on success
or a negative error value.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-8-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Alan Maguire
c4d0bfb450 bpf: Add bpf_snprintf_btf helper
A helper is added to support tracing kernel type information in BPF
using the BPF Type Format (BTF).  Its signature is

long bpf_snprintf_btf(char *str, u32 str_size, struct btf_ptr *ptr,
		      u32 btf_ptr_size, u64 flags);

struct btf_ptr * specifies

- a pointer to the data to be traced
- the BTF id of the type of data pointed to
- a flags field is provided for future use; these flags
  are not to be confused with the BTF_F_* flags
  below that control how the btf_ptr is displayed; the
  flags member of the struct btf_ptr may be used to
  disambiguate types in kernel versus module BTF, etc;
  the main distinction is the flags relate to the type
  and information needed in identifying it; not how it
  is displayed.

For example a BPF program with a struct sk_buff *skb
could do the following:

	static struct btf_ptr b = { };

	b.ptr = skb;
	b.type_id = __builtin_btf_type_id(struct sk_buff, 1);
	bpf_snprintf_btf(str, sizeof(str), &b, sizeof(b), 0, 0);

Default output looks like this:

(struct sk_buff){
 .transport_header = (__u16)65535,
 .mac_header = (__u16)65535,
 .end = (sk_buff_data_t)192,
 .head = (unsigned char *)0x000000007524fd8b,
 .data = (unsigned char *)0x000000007524fd8b,
 .truesize = (unsigned int)768,
 .users = (refcount_t){
  .refs = (atomic_t){
   .counter = (int)1,
  },
 },
}

Flags modifying display are as follows:

- BTF_F_COMPACT:	no formatting around type information
- BTF_F_NONAME:		no struct/union member names/types
- BTF_F_PTR_RAW:	show raw (unobfuscated) pointer values;
			equivalent to %px.
- BTF_F_ZERO:		show zero-valued struct/union members;
			they are not displayed by default

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-4-git-send-email-alan.maguire@oracle.com
2020-09-28 18:26:58 -07:00
Song Liu
1b4d60ec16 bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint
Add .test_run for raw_tracepoint. Also, introduce a new feature that runs
the target program on a specific CPU. This is achieved by a new flag in
bpf_attr.test, BPF_F_TEST_RUN_ON_CPU. When this flag is set, the program
is triggered on cpu with id bpf_attr.test.cpu. This feature is needed for
BPF programs that handle perf_event and other percpu resources, as the
program can access these resource locally.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200925205432.1777-2-songliubraving@fb.com
2020-09-28 21:52:36 +02:00
Rajkumar Manoharan
f5bec330e3 nl80211: extend support to config spatial reuse parameter set
Allow the user to configure below Spatial Reuse Parameter Set element.
  * Non-SRG OBSS PD Max Offset
  * SRG BSS Color Bitmap
  * SRG Partial BSSID Bitmap

Signed-off-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
Link: https://lore.kernel.org/r/1601278091-20313-2-git-send-email-rmanohar@codeaurora.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-09-28 15:07:41 +02:00
Thomas Pedersen
58ef7c1b55 nl80211: include frequency offset in survey info
Recently channels gained a potential frequency offset, so
include this in the per-channel survey info.

Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200922022818.15855-16-thomas@adapt-ip.com
[add the offset only if non-zero]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-09-28 14:09:52 +02:00
Alexander Graf
1a155254ff KVM: x86: Introduce MSR filtering
It's not desireable to have all MSRs always handled by KVM kernel space. Some
MSRs would be useful to handle in user space to either emulate behavior (like
uCode updates) or differentiate whether they are valid based on the CPU model.

To allow user space to specify which MSRs it wants to see handled by KVM,
this patch introduces a new ioctl to push filter rules with bitmaps into
KVM. Based on these bitmaps, KVM can then decide whether to reject MSR access.
With the addition of KVM_CAP_X86_USER_SPACE_MSR it can also deflect the
denied MSR events to user space to operate on.

If no filter is populated, MSR handling stays identical to before.

Signed-off-by: Alexander Graf <graf@amazon.com>

Message-Id: <20200925143422.21718-8-graf@amazon.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-28 07:58:08 -04:00
Alexander Graf
1ae099540e KVM: x86: Allow deflecting unknown MSR accesses to user space
MSRs are weird. Some of them are normal control registers, such as EFER.
Some however are registers that really are model specific, not very
interesting to virtualization workloads, and not performance critical.
Others again are really just windows into package configuration.

Out of these MSRs, only the first category is necessary to implement in
kernel space. Rarely accessed MSRs, MSRs that should be fine tunes against
certain CPU models and MSRs that contain information on the package level
are much better suited for user space to process. However, over time we have
accumulated a lot of MSRs that are not the first category, but still handled
by in-kernel KVM code.

This patch adds a generic interface to handle WRMSR and RDMSR from user
space. With this, any future MSR that is part of the latter categories can
be handled in user space.

Furthermore, it allows us to replace the existing "ignore_msrs" logic with
something that applies per-VM rather than on the full system. That way you
can run productive VMs in parallel to experimental ones where you don't care
about proper MSR handling.

Signed-off-by: Alexander Graf <graf@amazon.com>
Reviewed-by: Jim Mattson <jmattson@google.com>

Message-Id: <20200925143422.21718-3-graf@amazon.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-28 07:58:04 -04:00
Thomas Pedersen
d2b7588a47 nl80211: support S1G capability overrides in assoc
NL80211_ATTR_S1G_CAPABILITY can be passed along with
NL80211_ATTR_S1G_CAPABILITY_MASK to NL80211_CMD_ASSOCIATE
to indicate S1G capabilities which should override the
hardware capabilities in eg. the association request.

Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200922022818.15855-4-thomas@adapt-ip.com
[johannes: always require both attributes together, commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-09-28 13:53:05 +02:00
Tova Mussai
c8cb5b854b nl80211/cfg80211: support 6 GHz scanning
Support 6 GHz scanning, by
 * a new scan flag to scan for colocated BSSes advertised
   by (and found) APs on 2.4 & 5 GHz
 * doing the necessary reduced neighbor report parsing for
   this, to find them
 * adding the ability to split the scan request in case the
   device by itself cannot support this.

Also add some necessary bits in mac80211 to not break with
these changes.

Signed-off-by: Tova Mussai <tova.mussai@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20200918113313.232917c93af9.Ida22f0212f9122f47094d81659e879a50434a6a2@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-09-28 13:53:04 +02:00
Dafna Hirschfeld
62aacfa9bf media: v4l2: extend the CSC API to subdevice.
This patch extends the CSC API in video devices to be supported
also on sub-devices. The flag V4L2_MBUS_FRAMEFMT_SET_CSC set by
the application when calling VIDIOC_SUBDEV_S_FMT ioctl.
The flags:

V4L2_SUBDEV_MBUS_CODE_CSC_COLORSPACE,
V4L2_SUBDEV_MBUS_CODE_CSC_XFER_FUNC,
V4L2_SUBDEV_MBUS_CODE_CSC_YCBCR_ENC/V4L2_SUBDEV_MBUS_CODE_CSC_HSV_ENC
V4L2_SUBDEV_MBUS_CODE_CSC_QUANTIZATION

are set by the driver in the VIDIOC_SUBDEV_ENUM_MBUS_CODE ioctl.

New 'flags' fields were added to the structs
v4l2_subdev_mbus_code_enum, v4l2_mbus_framefmt which are borrowed
from the 'reserved' field

The patch also replaces the 'ycbcr_enc' field in
'struct v4l2_mbus_framefmt' with a union that includes 'hsv_enc'

Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-09-26 10:22:29 +02:00
Dafna Hirschfeld
b38c73ca1c media: v4l2: add support for colorspace conversion API (CSC) for video capture
For video capture it is the driver that reports the colorspace,
transfer function, Y'CbCr/HSV encoding and quantization range
used by the video, and there is no way to request something
different, even though many HDTV receivers have some sort of
colorspace conversion capabilities.

For output video this feature already exists since the application
specifies this information for the video format it will send out, and
the transmitter will enable any available CSC if a format conversion has
to be performed in order to match the capabilities of the sink.

For video capture we propose adding new v4l2_pix_format flag:
V4L2_PIX_FMT_FLAG_SET_CSC. The flag is set by the application,
the driver will interpret the colorspace, xfer_func, ycbcr_enc/hsv_enc
and quantization fields as the requested colorspace information and will
attempt to do the conversion it supports.

Drivers set the flags
V4L2_FMT_FLAG_CSC_COLORSPACE,
V4L2_FMT_FLAG_CSC_XFER_FUNC,
V4L2_FMT_FLAG_CSC_YCBCR_ENC/V4L2_FMT_FLAG_CSC_HSV_ENC,
V4L2_FMT_FLAG_CSC_QUANTIZATION,
in the flags field of the struct v4l2_fmtdesc during enumeration to
indicate that they support colorspace conversion for the respective field.

Drivers do not have to actually look at the flags. If the flags are not
set, then the fields 'colorspace', 'xfer_func', 'ycbcr_enc/hsv_enc',
and 'quantization' are set to the default values by the core, i.e. just
pass on the received format without conversion.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-09-26 10:20:57 +02:00
Jacob Keller
5d5b4128c4 devlink: introduce flash update overwrite mask
Sections of device flash may contain settings or device identifying
information. When performing a flash update, it is generally expected
that these settings and identifiers are not overwritten.

However, it may sometimes be useful to allow overwriting these fields
when performing a flash update. Some examples include, 1) customizing
the initial device config on first programming, such as overwriting
default device identifying information, or 2) reverting a device
configuration to known good state provided in the new firmware image, or
3) in case it is suspected that current firmware logic for managing the
preservation of fields during an update is broken.

Although some devices are able to completely separate these types of
settings and fields into separate components, this is not true for all
hardware.

To support controlling this behavior, a new
DEVLINK_ATTR_FLASH_UPDATE_OVERWRITE_MASK is defined. This is an
nla_bitfield32 which will define what subset of fields in a component
should be overwritten during an update.

If no bits are specified, or of the overwrite mask is not provided, then
an update should not overwrite anything, and should maintain the
settings and identifiers as they are in the previous image.

If the overwrite mask has the DEVLINK_FLASH_OVERWRITE_SETTINGS bit set,
then the device should be configured to overwrite any of the settings in
the requested component with settings found in the provided image.

Similarly, if the DEVLINK_FLASH_OVERWRITE_IDENTIFIERS bit is set, the
device should be configured to overwrite any device identifiers in the
requested component with the identifiers from the image.

Multiple overwrite modes may be combined to indicate that a combination
of the set of fields that should be overwritten.

Drivers which support the new overwrite mask must set the
DEVLINK_SUPPORT_FLASH_UPDATE_OVERWRITE_MASK in the
supported_flash_update_params field of their devlink_ops.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-25 17:20:57 -07:00
Martin KaFai Lau
27e5203bd9 bpf: Change bpf_sk_assign to accept ARG_PTR_TO_BTF_ID_SOCK_COMMON
This patch changes the bpf_sk_assign() to take
ARG_PTR_TO_BTF_ID_SOCK_COMMON such that they will work with the pointer
returned by the bpf_skc_to_*() helpers also.

The bpf_sk_lookup_assign() is taking ARG_PTR_TO_SOCKET_"OR_NULL".  Meaning
it specifically takes a literal NULL.  ARG_PTR_TO_BTF_ID_SOCK_COMMON
does not allow a literal NULL, so another ARG type is required
for this purpose and another follow-up patch can be used if
there is such need.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200925000415.3857374-1-kafai@fb.com
2020-09-25 13:58:02 -07:00
Martin KaFai Lau
c0df236e13 bpf: Change bpf_tcp_*_syncookie to accept ARG_PTR_TO_BTF_ID_SOCK_COMMON
This patch changes the bpf_tcp_*_syncookie() to take
ARG_PTR_TO_BTF_ID_SOCK_COMMON such that they will work with the pointer
returned by the bpf_skc_to_*() helpers also.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/20200925000409.3856725-1-kafai@fb.com
2020-09-25 13:58:01 -07:00
Martin KaFai Lau
592a349864 bpf: Change bpf_sk_storage_*() to accept ARG_PTR_TO_BTF_ID_SOCK_COMMON
This patch changes the bpf_sk_storage_*() to take
ARG_PTR_TO_BTF_ID_SOCK_COMMON such that they will work with the pointer
returned by the bpf_skc_to_*() helpers also.

A micro benchmark has been done on a "cgroup_skb/egress" bpf program
which does a bpf_sk_storage_get().  It was driven by netperf doing
a 4096 connected UDP_STREAM test with 64bytes packet.
The stats from "kernel.bpf_stats_enabled" shows no meaningful difference.

The sk_storage_get_btf_proto, sk_storage_delete_btf_proto,
btf_sk_storage_get_proto, and btf_sk_storage_delete_proto are
no longer needed, so they are removed.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/20200925000402.3856307-1-kafai@fb.com
2020-09-25 13:58:01 -07:00
Martin KaFai Lau
a5fa25adf0 bpf: Change bpf_sk_release and bpf_sk_*cgroup_id to accept ARG_PTR_TO_BTF_ID_SOCK_COMMON
The previous patch allows the networking bpf prog to use the
bpf_skc_to_*() helpers to get a PTR_TO_BTF_ID socket pointer,
e.g. "struct tcp_sock *".  It allows the bpf prog to read all the
fields of the tcp_sock.

This patch changes the bpf_sk_release() and bpf_sk_*cgroup_id()
to take ARG_PTR_TO_BTF_ID_SOCK_COMMON such that they will
work with the pointer returned by the bpf_skc_to_*() helpers
also.  For example, the following will work:

	sk = bpf_skc_lookup_tcp(skb, tuple, tuplen, BPF_F_CURRENT_NETNS, 0);
	if (!sk)
		return;
	tp = bpf_skc_to_tcp_sock(sk);
	if (!tp) {
		bpf_sk_release(sk);
		return;
	}
	lsndtime = tp->lsndtime;
	/* Pass tp to bpf_sk_release() will also work */
	bpf_sk_release(tp);

Since PTR_TO_BTF_ID could be NULL, the helper taking
ARG_PTR_TO_BTF_ID_SOCK_COMMON has to check for NULL at runtime.

A btf_id of "struct sock" may not always mean a fullsock.  Regardless
the helper's running context may get a non-fullsock or not,
considering fullsock check/handling is pretty cheap, it is better to
keep the same verifier expectation on helper that takes ARG_PTR_TO_BTF_ID*
will be able to handle the minisock situation.  In the bpf_sk_*cgroup_id()
case,  it will try to get a fullsock by using sk_to_full_sk() as its
skb variant bpf_sk"b"_*cgroup_id() has already been doing.

bpf_sk_release can already handle minisock, so nothing special has to
be done.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200925000356.3856047-1-kafai@fb.com
2020-09-25 13:58:01 -07:00
Peter Oskolkov
2a36ab717e rseq/membarrier: Add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ
This patchset is based on Google-internal RSEQ work done by Paul
Turner and Andrew Hunter.

When working with per-CPU RSEQ-based memory allocations, it is
sometimes important to make sure that a global memory location is no
longer accessed from RSEQ critical sections. For example, there can be
two per-CPU lists, one is "active" and accessed per-CPU, while another
one is inactive and worked on asynchronously "off CPU" (e.g.  garbage
collection is performed). Then at some point the two lists are
swapped, and a fast RCU-like mechanism is required to make sure that
the previously active list is no longer accessed.

This patch introduces such a mechanism: in short, membarrier() syscall
issues an IPI to a CPU, restarting a potentially active RSEQ critical
section on the CPU.

Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lkml.kernel.org/r/20200923233618.2572849-1-posk@google.com
2020-09-25 14:23:27 +02:00