Since commit cd17d777 ("bpf/tools: sync bpf.h") clang decided
that it can do a single u64 store into user_ip6[2] instead of two
separate u32 ones:

 #  17: (18) r2 = 0x100000000000000
 #  ; ctx->user_ip6[2] = bpf_htonl(DST_REWRITE_IP6_2);
 #  19: (7b) *(u64 *)(r1 +16) = r2
 #  invalid bpf_context access off=16 size=8

>From the compiler point of view it does look like a correct thing
to do, so let's support it on the kernel side.

Credit to Andrii Nakryiko for a proper implementation of
bpf_ctx_wide_store_ok.

Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Fixes: cd17d777 ("bpf/tools: sync bpf.h")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Andrii Nakryiko says:

====================
This patchset adds a high-level API for setting up and polling perf buffers
associated with BPF_MAP_TYPE_PERF_EVENT_ARRAY map. Details of APIs are
described in corresponding commit.

Patch #1 adds a set of APIs to set up and work with perf buffer.
Patch #2 enhances libbpf to support auto-setting PERF_EVENT_ARRAY map size.
Patch #3 adds test.
Patch #4 converts bpftool map event_pipe to new API.
Patch #5 updates README to mention perf_buffer_ prefix.

v6->v7:
- __x64_ syscall prefix (Yonghong);
v5->v6:
- fix C99 for loop variable initialization usage (Yonghong);
v4->v5:
- initialize perf_buffer_raw_opts in bpftool map event_pipe (Jakub);
- add perf_buffer_ to README;
v3->v4:
- fixed bpftool event_pipe cmd error handling (Jakub);
v2->v3:
- added perf_buffer__new_raw for more low-level control;
- converted bpftool map event_pipe to new API (Daniel);
- fixed bug with error handling in create_maps (Song);
v1->v2:
- add auto-sizing of PERF_EVENT_ARRAY maps;
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

perf_buffer "object" is part of libbpf API now, add it to the list of
libbpf function prefixes.
Suggested-by: Daniel Borkman <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Switch event_pipe implementation to rely on new libbpf perf buffer API
(it's raw low-level variant).
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Add test verifying perf buffer API functionality.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

For BPF_MAP_TYPE_PERF_EVENT_ARRAY typically correct size is number of
possible CPUs. This is impossible to specify at compilation time. This
change adds automatic setting of PERF_EVENT_ARRAY size to number of
system CPUs, unless non-zero size is specified explicitly. This allows
to adjust size for advanced specific cases, while providing convenient
and logical defaults.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

BPF_MAP_TYPE_PERF_EVENT_ARRAY map is often used to send data from BPF program
to user space for additional processing. libbpf already has very low-level API
to read single CPU perf buffer, bpf_perf_event_read_simple(), but it's hard to
use and requires a lot of code to set everything up. This patch adds
perf_buffer abstraction on top of it, abstracting setting up and polling
per-CPU logic into simple and convenient API, similar to what BCC provides.

perf_buffer__new() sets up per-CPU ring buffers and updates corresponding BPF
map entries. It accepts two user-provided callbacks: one for handling raw
samples and one for get notifications of lost samples due to buffer overflow.

perf_buffer__new_raw() is similar, but provides more control over how
perf events are set up (by accepting user-provided perf_event_attr), how
they are handled (perf_event_header pointer is passed directly to
user-provided callback), and on which CPUs ring buffers are created
(it's possible to provide a list of CPUs and corresponding map keys to
update). This API allows advanced users fuller control.

perf_buffer__poll() is used to fetch ring buffer data across all CPUs,
utilizing epoll instance.

perf_buffer__free() does corresponding clean up and unsets FDs from BPF map.

All APIs are not thread-safe. User should ensure proper locking/coordination if
used in multi-threaded set up.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Forgot to add it in the original patch.

Fixes: b5587398 ("selftests/bpf: test BPF_SOCK_OPS_RTT_CB")
Reported-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Commit 2589726d ("bpf: introduce bounded loops") caused a change
in the way some registers liveliness is reported in the test_align.
Add missing "_w" to a couple of tests. Note, there are no offset
changes!

Fixes: 2589726d ("bpf: introduce bounded loops")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Commit 66d0d5a8 ("riscv: bpf: eliminate zero extension code-gen")
added the new zero-extension optimization for some BPF ALU operations.

Since then, bugs in the JIT that have been fixed in the bpf tree require
this optimization to be added to other operations: commit 1e692f09
("bpf, riscv: clear high 32 bits for ALU32 add/sub/neg/lsh/rsh/arsh"),
and commit fe121ee5 ("bpf, riscv: clear target register high 32-bits
for and/or/xor on ALU32").

Now that these have been merged to bpf-next, the zext optimization can
be enabled for the fixed operations.
Signed-off-by: Luke Nelson <luke.r.nels@gmail.com>
Cc: Song Liu <liu.song.a23@gmail.com>
Cc: Jiong Wang <jiong.wang@netronome.com>
Cc: Xi Wang <xi.wang@gmail.com>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Acked-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Michael reported crash with by bpf program in json mode on powerpc:

  # bpftool prog -p dump jited id 14
  [{
        "name": "0xd00000000a9aa760",
        "insns": [{
                "pc": "0x0",
                "operation": "nop",
                "operands": [null
                ]
            },{
                "pc": "0x4",
                "operation": "nop",
                "operands": [null
                ]
            },{
                "pc": "0x8",
                "operation": "mflr",
  Segmentation fault (core dumped)

The code is assuming char pointers in format, which is not always
true at least for powerpc. Fixing this by dumping the whole string
into buffer based on its format.

Please note that libopcodes code does not check return values from
fprintf callback, but as per Jakub suggestion returning -1 on allocation
failure so we do the best effort to propagate the error.

Fixes: 107f0412 ("tools: bpftool: add JSON output for `bpftool prog dump jited *` command")
Reported-by: Michael Petlan <mpetlan@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Add a new "bpftool prog run" subcommand to run a loaded program on input
data (and possibly with input context) passed by the user.

Print output data (and output context if relevant) into a file or into
the console. Print return value and duration for the test run into the
console.

A "repeat" argument can be passed to run the program several times in a
row.

The command does not perform any kind of verification based on program
type (Is this program type allowed to use an input context?) or on data
consistency (Can I work with empty input data?), this is left to the
kernel.

Example invocation:

    # perl -e 'print "\x0" x 14' | ./bpftool prog run \
            pinned /sys/fs/bpf/sample_ret0 \
            data_in - data_out - repeat 5
    0000000 0000 0000 0000 0000 0000 0000 0000      | ........ ......
    Return value: 0, duration (average): 260ns

When one of data_in or ctx_in is "-", bpftool reads from standard input,
in binary format. Other formats (JSON, hexdump) might be supported (via
an optional command line keyword like "data_fmt_in") in the future if
relevant, but this would require doing more parsing in bpftool.

v2:
- Fix argument names for function check_single_stdin(). (Yonghong)
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Andrii Nakryiko says:

====================
This patch set implements an update to how BTF-defined maps are specified. The
change is in how integer attributes, e.g., type, max_entries, map_flags, are
specified: now they are captured as part of map definition struct's BTF type
information (using array dimension), eliminating the need for compile-time
data initialization and keeping all the metadata in one place.

All existing selftests that were using BTF-defined maps are updated, along
with some other selftests, that were switched to new syntax.

v4->v5:
- revert sample_map_ret0.c, which is loaded with iproute2 (kernel test robot);
v3->v4:
- add acks;
- fix int -> uint type in commit message;
v2->v3:
- rename __int into __uint (Yonghong);
v1->v2:
- split bpf_helpers.h change from libbpf change (Song).
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Convert selftests that were originally left out and new ones added
recently to consistently use BTF-defined maps.
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Convert all the existing selftests that are already using BTF-defined
maps to use new syntax (with no static data initialization).
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Add simple __uint and __type macro that hide details of how type and
integer values are captured in BTF-defined maps.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Change BTF-defined map definitions to capture compile-time integer
values as part of BTF type definition, to avoid split of key/value type
information and actual type/size/flags initialization for maps.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Andrii Nakryiko says:

====================
This patchset adds the following APIs to allow attaching BPF programs to
tracing entities:
- bpf_program__attach_perf_event for attaching to any opened perf event FD,
  allowing users full control;
- bpf_program__attach_kprobe for attaching to kernel probes (both entry and
  return probes);
- bpf_program__attach_uprobe for attaching to user probes (both entry/return);
- bpf_program__attach_tracepoint for attaching to kernel tracepoints;
- bpf_program__attach_raw_tracepoint for attaching to raw kernel tracepoint
  (wrapper around bpf_raw_tracepoint_open);

This set of APIs makes libbpf more useful for tracing applications.

All attach APIs return abstract struct bpf_link that encapsulates logic of
detaching BPF program. See patch #2 for details. bpf_assoc was considered as
an alternative name for this opaque "handle", but bpf_link seems to be
appropriate semantically and is nice and short.

Pre-patch #1 makes internal libbpf_strerror_r helper function work w/ negative
error codes, lifting the burder off callers to keep track of error sign.
Patch #2 adds bpf_link abstraction.
Patch #3 adds attach_perf_event, which is the base for all other APIs.
Patch #4 adds kprobe/uprobe APIs.
Patch #5 adds tracepoint API.
Patch #6 adds raw_tracepoint API.
Patch #7 converts one existing test to use attach_perf_event.
Patch #8 adds new kprobe/uprobe tests.
Patch #9 converts some selftests currently using tracepoint to new APIs.

v4->v5:
- typo and small nits (Yonghong);
- validate pfd in attach_perf_event (Yonghong);
- parse_uint_from_file fixes (Yonghong);
- check for malloc failure in attach_raw_tracepoint (Yonghong);
- attach_probes selftests clean up fixes (Yonghong);
v3->v4:
- proper errno handling (Stanislav);
- bpf_fd -> prog_fd (Stanislav);
- switch to fprintf (Song);
v2->v3:
- added bpf_link concept (Daniel);
- didn't add generic bpf_link__attach_program for reasons described in [0];
- dropped Stanislav's Reviewed-by from patches #2-#6, in case he doesn't like
  the change;
v1->v2:
- preserve errno before close() call (Stanislav);
- use libbpf_perf_event_disable_and_close in selftest (Stanislav);
- remove unnecessary memset (Stanislav);

[0] https://lore.kernel.org/bpf/CAEf4BzZ7EM5eP2eaZn7T2Yb5QgVRiwAs+epeLR1g01TTx-6m6Q@mail.gmail.com/
====================
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Convert some existing tests that attach to tracepoints to use
bpf_program__attach_tracepoint API instead.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Add tests verifying kprobe/kretprobe/uprobe/uretprobe APIs work as
expected.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Use new bpf_program__attach_perf_event() in test previously relying on
direct ioctl manipulations.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Add a wrapper utilizing bpf_link "infrastructure" to allow attaching BPF
programs to raw tracepoints.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Allow attaching BPF programs to kernel tracepoint BPF hooks specified by
category and name.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Add ability to attach to kernel and user probes and retprobes.
Implementation depends on perf event support for kprobes/uprobes.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

bpf_program__attach_perf_event allows to attach BPF program to existing
perf event hook, providing most generic and most low-level way to attach BPF
programs. It returns struct bpf_link, which should be passed to
bpf_link__destroy to detach and free resources, associated with a link.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

bpf_link is an abstraction of an association of a BPF program and one of
many possible BPF attachment points (hooks). This allows to have uniform
interface for detaching BPF programs regardless of the nature of link
and how it was created. Details of creation and setting up of a specific
bpf_link is handled by corresponding attachment methods
(bpf_program__attach_xxx) added in subsequent commits. Once successfully
created, bpf_link has to be eventually destroyed with
bpf_link__destroy(), at which point BPF program is disassociated from
a hook and all the relevant resources are freed.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

It's often inconvenient to switch sign of error when passing it into
libbpf_strerror_r. It's better for it to handle that automatically.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Daniel Borkmann says:

====================
pull-request: bpf-next 2019-07-03

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

There is a minor merge conflict in mlx5 due to 8960b389 ("linux/dim:
Rename externally used net_dim members") which has been pulled into your
tree in the meantime, but resolution seems not that bad ... getting current
bpf-next out now before there's coming more on mlx5. ;) I'm Cc'ing Saeed
just so he's aware of the resolution below:

** First conflict in drivers/net/ethernet/mellanox/mlx5/core/en_main.c:

  <<<<<<< HEAD
  static int mlx5e_open_cq(struct mlx5e_channel *c,
                           struct dim_cq_moder moder,
                           struct mlx5e_cq_param *param,
                           struct mlx5e_cq *cq)
  =======
  int mlx5e_open_cq(struct mlx5e_channel *c, struct net_dim_cq_moder moder,
                    struct mlx5e_cq_param *param, struct mlx5e_cq *cq)
  >>>>>>> e5a3e259

Resolution is to take the second chunk and rename net_dim_cq_moder into
dim_cq_moder. Also the signature for mlx5e_open_cq() in ...

  drivers/net/ethernet/mellanox/mlx5/core/en.h +977

... and in mlx5e_open_xsk() ...

  drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c +64

... needs the same rename from net_dim_cq_moder into dim_cq_moder.

** Second conflict in drivers/net/ethernet/mellanox/mlx5/core/en_main.c:

  <<<<<<< HEAD
          int cpu = cpumask_first(mlx5_comp_irq_get_affinity_mask(priv->mdev, ix));
          struct dim_cq_moder icocq_moder = {0, 0};
          struct net_device *netdev = priv->netdev;
          struct mlx5e_channel *c;
          unsigned int irq;
  =======
          struct net_dim_cq_moder icocq_moder = {0, 0};
  >>>>>>> e5a3e259

Take the second chunk and rename net_dim_cq_moder into dim_cq_moder
as well.

Let me know if you run into any issues. Anyway, the main changes are:

1) Long-awaited AF_XDP support for mlx5e driver, from Maxim.

2) Addition of two new per-cgroup BPF hooks for getsockopt and
   setsockopt along with a new sockopt program type which allows more
   fine-grained pass/reject settings for containers. Also add a sock_ops
   callback that can be selectively enabled on a per-socket basis and is
   executed for every RTT to help tracking TCP statistics, both features
   from Stanislav.

3) Follow-up fix from loops in precision tracking which was not propagating
   precision marks and as a result verifier assumed that some branches were
   not taken and therefore wrongly removed as dead code, from Alexei.

4) Fix BPF cgroup release synchronization race which could lead to a
   double-free if a leaf's cgroup_bpf object is released and a new BPF
   program is attached to the one of ancestor cgroups in parallel, from Roman.

5) Support for bulking XDP_TX on veth devices which improves performance
   in some cases by around 9%, from Toshiaki.

6) Allow for lookups into BPF devmap and improve feedback when calling into
   bpf_redirect_map() as lookup is now performed right away in the helper
   itself, from Toke.

7) Add support for fq's Earliest Departure Time to the Host Bandwidth
   Manager (HBM) sample BPF program, from Lawrence.

8) Various cleanups and minor fixes all over the place from many others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Both MTK_TRGMII_MT7621_CLK and MTK_PATH_BIT are defined as bit 10.

This can causes issues on non-MT7621 devices which has the
MTK_PATH_BIT(MTK_ETH_PATH_GMAC1_RGMII) and MTK_TRGMII capability set.
The wrong TRGMII setup code can be executed. The current wrongly executed
code doesn’t do any harm on MT7623 and the TRGMII setup for the MT7623
SOC side is done in MT7530 driver So it wasn’t noticed in the test.

Move all capability bits in one enum so that they are all unique and easy
to expand in the future.

Because mtk_eth_path enum is merged in to mkt_eth_capabilities, the
variable path value is no longer between 0 to number of paths,
mtk_eth_path_name can’t be used anymore in this form. Convert the
mtk_eth_path_name array to a function to lookup the pathname.

The old code walked thru the mtk_eth_path enum, which is also merged
with mkt_eth_capabilities. Expand array mtk_eth_muxc so it can store the
name and capability bit of the mux. Convert the code so it can walk thru
the mtk_eth_muxc array.

Fixes: 8efaa653 ("net: ethernet: mediatek: Add MT7621 TRGMII mode support")
Signed-off-by: René van Dorst <opensource@vdorst.com>

v1->v2:
- Move all capability bits in one enum, suggested by Willem de Bruijn
- Convert the mtk_eth_path_name array to a function to lookup the pathname
- Expand array mtk_eth_muxc so it can also store the name and capability
  bit of the mux
- Updated commit message
Signed-off-by: David S. Miller <davem@davemloft.net>

Enable GMAC v4.xx and beyond to support 16KiB buffer.
Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, gratuitous ARP/ND packets are sent every `miimon'
milliseconds. This commit allows a user to specify a custom delay
through a new option, `peer_notif_delay'.

Like for `updelay' and `downdelay', this delay should be a multiple of
`miimon' to avoid managing an additional work queue. The configuration
logic is copied from `updelay' and `downdelay'. However, the default
value cannot be set using a module parameter: Netlink or sysfs should
be used to configure this feature.

When setting `miimon' to 100 and `peer_notif_delay' to 500, we can
observe the 500 ms delay is respected:

    20:30:19.354693 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28
    20:30:19.874892 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28
    20:30:20.394919 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28
    20:30:20.914963 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28

In bond_mii_monitor(), I have tried to keep the lock logic readable.
The change is due to the fact we cannot rely on a notification to
lower the value of `bond->send_peer_notif' as `NETDEV_NOTIFY_PEERS' is
only triggered once every N times, while we need to decrement the
counter each time.

iproute2 also needs to be updated to be able to specify this new
attribute through `ip link'.
Signed-off-by: Vincent Bernat <vincent@bernat.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

The variable err is being assigned with a value that is never
read and it is being updated in the next statement with a new value.
The assignment is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently the check to see if a page is allocated is incorrect
and is checking if the pointer page is null, not *page as
intended.  Fix this.

Addresses-Coverity: ("Dereference before null check")
Fixes: f5cedc84 ("gve: Add transmit and receive support")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Paolo Abeni says:

====================
net: use ICW for sk_proto->{send,recv}msg

This series extends ICW usage to one of the few remaining spots in fast-path
still hitting per packet retpoline overhead, namely the sk_proto->{send,recv}msg
calls.

The first 3 patches in this series refactor the existing code so that applying
the ICW macros is straight-forward: we demux inet_{recv,send}msg in ipv4 and
ipv6 variants so that each of them can easily select the appropriate TCP or UDP
direct call. While at it, a new helper is created to avoid excessive code
duplication, and the current ICWs for inet_{recv,send}msg are adjusted
accordingly.

The last 2 patches really introduce the new ICW use-case, respectively for the
ipv6 and the ipv4 code path.

This gives up to 5% performance improvement under UDP flood, and smaller but
measurable gains for TCP RR workloads.

v1 -> v2:
 - drop inet6_{recv,send}msg declaration from header file,
   prefer ICW macro instead
 - avoid unneeded reclaration for udp_sendmsg, as suggested by Willem
====================
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This avoids an indirect call per syscall for common ipv4 transports

v1 -> v2:
 - avoid unneeded reclaration for udp_sendmsg, as suggested by Willem
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This avoids an indirect call per syscall for common ipv6 transports
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After the previous patch we have ipv{6,4} variants for {recv,send}msg,
we should use the generic _INET ICW variant to call into the proper
build-in.

This also allows dropping the now unused and rather ugly _INET4 ICW macro

v1 -> v2:
 - use ICW macro to declare inet6_{recv,send}msg
 - fix a couple of checkpatch offender in the code context
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This will simplify indirect call wrapper invocation in the following
patch.

No functional change intended, any - out-of-tree - IPv6 user of
inet_{recv,send}msg can keep using the existing functions.

SCTP code still uses the existing version even for ipv6: as this series
will not add ICW for SCTP, moving to the new helper would not give
any benefit.

The only other in-kernel user of inet_{recv,send}msg is
pvcalls_conn_back_read(), but psvcalls explicitly creates only IPv4 socket,
so no need to update that code path, too.

v1 -> v2: drop inet6_{recv,send}msg declaration from header file,
   prefer ICW macro instead
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The same code is replicated verbatim in multiple places, and the next
patches will introduce an additional user for it. Factor out a
helper and use it where appropriate. No functional change intended.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The variable err is being initialized with a value that is never
read and it is being updated later with a new value. The
initialization is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>