Граф коммитов

752765 Коммитов

Автор SHA1 Сообщение Дата
Julian Wiedmann 21b1702af1 s390/qeth: improve fallback to random MAC address
If READ MAC fails to fetch a valid MAC address, allow some more device
types (IQD and z/VM OSD) to fall back to a random address.
Also use eth_hw_addr_random(), for indicating to userspace that the
address type is NET_ADDR_RANDOM.

Note that while z/VM has various protection schemes to prohibit
custom addresses on its NICs, they are all optional. So we should at
least give it a try.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:49 -04:00
Kittipon Meesompop d7e6ed97b5 s390/qeth: add IPv6 RX checksum offload support
Check if a qeth device supports IPv6 RX checksum offload, and hook it up
into the existing NETIF_F_RXCSUM support.
As NETIF_F_RXCSUM is now backed by a combination of HW Assists, we need
to be a little smarter when dealing with errors during a configuration
change:
- switching on NETIF_F_RXCSUM only makes sense if at least one HW Assist
  was enabled successfully.
- for switching off NETIF_F_RXCSUM, all available HW Assists need to be
  deactivated.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:49 -04:00
Kittipon Meesompop 571f9dd802 s390/qeth: add IPv6 TX checksum offload support
Check if a qeth device supports IPv6 TX checksum offload, and advertise
NETIF_F_IPV6_CSUM accordingly. Add support for setting the relevant bits
in IPv6 packet descriptors.

Currently this has only limited use (ie. UDP, or Jumbo Frames). For any
TCP traffic with a standard MSS, the TCP checksum gets calculated
as part of the linear GSO segmentation.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:49 -04:00
Kittipon Meesompop a8155b009f s390/qeth: extend Checksum Offload Assists for IPv6
Add some wrappers to make the protocol-specific Assist code a little
more generic, and use them for sending protocol-agnostic commands in
the Checksum Offload Assist code.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:49 -04:00
Kittipon Meesompop ee75fb8615 s390/qeth: query IPv6 assists during hardsetup
For new functionality, the L2 subdriver will start using IPv6 assists.
So move the query from the L3 subdriver into the common setup path.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:49 -04:00
Kittipon Meesompop 3aade31b2f s390/qeth: add stats counter for RX csum offload
This matches the statistics we gather for the TX offload path.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:48 -04:00
Julian Wiedmann b339c24ebf s390/qeth: disregard IPv4 header for RX csum offload
The kernel does its own validation of the IPv4 header checksum,
drivers/HW are not required to handle this.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:48 -04:00
Julian Wiedmann 6195b93661 s390/qeth: extract csum offload helpers
This consolidates the checksum offload code that was duplicated
over the two qeth subdrivers.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:48 -04:00
Kittipon Meesompop 1b81143281 s390/qeth: de-indent else after return
Trivial cleanup, in preparation for a subsequent patch.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:48 -04:00
Ursula Braun 71c4689780 s390/net: set HW port number in netdevice
struct net_device contains a dev_port field. Store the OSA port number
in this field.

Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:47 -04:00
Julian Wiedmann d8de0ddfad s390/qeth: don't worry about IPs on VLAN removal
When removing a VLAN ID on a L3 device, the driver currently attempts to
walk and unregister the VLAN device's IP addresses.
This can be safely removed - before qeth_l3_vlan_rx_kill_vid() even gets
called, we receive an inet[6]addr event for each IP on the device and
qeth_l3_handle_ip_event() unregisters the address accordingly.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:47 -04:00
Julian Wiedmann d4ac024688 s390/qeth: convert vlan spinlock to mutex
As the vid_list is only accessed from process context, there's no need to
protect it with a spinlock.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:47 -04:00
Julian Wiedmann 7bcd64eb8c s390/qeth: skip QDIO queue handler indirection
Both qeth sub drivers use the same QDIO queue handlers, there's no need
to expose them via the driver's discipline. No functional change.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:47 -04:00
YueHaibing d8fb1648fc bridge: use hlist_entry_safe
Use hlist_entry_safe() instead of open-coding it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:20:48 -04:00
David S. Miller 1e3ac2012d Merge branch 'liquidio-add-support-for-ndo_get_stats64'
Pradeep Nalla says:

====================
liquidio: add support for ndo_get_stats64

Support ndo_get_stats64 instead of ndo_get_stats.  Also add stats for
multicast and broadcast packets.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:19:39 -04:00
Pradeep Nalla 80002347d6 liquidio: add support for ndo_get_stats64 instead of ndo_get_stats
Support ndo_get_stats64 instead of ndo_get_stats.  Also add stats for
multicast and broadcast packets.

Signed-off-by: Pradeep Nalla <pradeep.nalla@cavium.com>
Acked-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:19:38 -04:00
Pradeep Nalla f058ca6b06 liquidio: move a couple of functions to lio_core.c
To support the next patch in this series which has code that calls
octnet_get_link_stats from two different .c files, move that function (and
its dependency octnet_nic_stats_callback) to lio_core.c.  Remove
octnet_get_link_stats's static declaration and add its function prototype
in octeon_network.h.

Signed-off-by: Pradeep Nalla <pradeep.nalla@cavium.com>
Acked-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:19:38 -04:00
David S. Miller 1ecd6e8ad9 phy: Temporary build fix after phylib changes.
Make PHYLIB boolean, because we reference phylib provided symbols now
from net/core/ethtool.c and therefore 'm' doesn't work.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:11:25 -04:00
David S. Miller 21fca6e01b Merge branch 'net-Extend-availability-of-PHY-statistics'
Florian Fainelli says:

====================
net: Extend availability of PHY statistics

This patch series adds support for retrieving PHY statistics with DSA switches
when the CPU port uses a PHY to PHY connection (as opposed to MAC to MAC).
To get there a number of things are done:

- first we move the code dealing with PHY statistics outside of net/core/ethtool.c
  and create helper functions since the same code will be reused
- then we allow network device drivers to provide an ethtool_get_phy_stats callback
  when the standard PHY library helpers are not suitable
- we update the DSA functions dealing with ethtool operations to get passed a
  stringset instead of assuming ETH_SS_STATS like they currently do
- then we provide a set of standard helpers within DSA as a framework and add
  the plumbing to allow retrieving the PHY statistics of the CPU port(s)
- finally plug support for retrieving such PHY statistics with the b53 driver

Changes in v3:

- retrict the b53 change to 539x and 531x5 series of switches
- added a change to dsa_loop.c to help test the feature

Changes in v2:

- got actual testing when the DSA master network device has a PHY that
  already provides statistics (thanks Nikita!)

- fixed the kbuild error reported when CONFIG_PHYLIB=n

- removed the checking of ops which is redundant and not needed
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:04 -04:00
Florian Fainelli 96cbddcd52 net: dsa: loop: Hook PHY statistics
We just return the same statistics through ethtool_get_stats() and
ethtool_get_phy_stats() for simplicity since this is just a mock-up driver.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:03 -04:00
Florian Fainelli c7d28c9df2 net: dsa: b53: Add support for reading PHY statistics
Allow the b53 driver to return PHY statistics when the CPU port used is
different than 5, 7 or 8, because those are typically PHY-less on most
devices. This is useful for debugging link problems between the switch
and an external host when using a non standard CPU port number (e.g: 4).

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:03 -04:00
Florian Fainelli cf96357303 net: dsa: Allow providing PHY statistics from CPU port
Implement the same type of ethtool diversion that we have for
ETH_SS_STATS and make it work with ETH_SS_PHY_STATS. This allows
providing PHY level statistics for CPU ports that are directly
connecting to a PHY device.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:03 -04:00
Florian Fainelli 6207a78c09 net: dsa: Add helper function to obtain PHY device of a given port
In preparation for having more call sites attempting to obtain a
reference against a PHY device corresponding to a particular port,
introduce a helper function for that purpose.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:03 -04:00
Florian Fainelli 89f0904834 net: dsa: Pass stringset to ethtool operations
Up until now we largely assumed that we were interested in ETH_SS_STATS
type of strings for all ethtool operations, this is about to change with
the introduction of additional string sets, e.g: ETH_SS_PHY_STATS.
Update all functions to take an appropriate stringset argument and act
on it when it is different than ETH_SS_STATS for now.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:03 -04:00
Florian Fainelli 1d1e79f1c6 net: dsa: Do not check for ethtool_ops validity
This is completely redundant with what netdev_set_default_ethtool_ops()
does, we are always guaranteed to have a valid dev->ethtool_ops pointer,
however, within that structure, not all function calls may be populated,
so we still have to check them individually.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:02 -04:00
Florian Fainelli 9994338227 net: Allow network devices to have PHY statistics
Add a new callback: get_ethtool_phy_stats() which allows network device
drivers not making use of the PHY library to return PHY statistics.
Update ethtool_get_phy_stats(), __ethtool_get_sset_count() and
__ethtool_get_strings() accordingly to interogate the network device
about ETH_SS_PHY_STATS.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:02 -04:00
Florian Fainelli c59530d0d5 net: Move PHY statistics code into PHY library helpers
In order to make it possible for network device drivers that do not
necessarily have a phy_device attached, but still report PHY statistics,
have a preliminary refactoring consisting in creating helper functions
that encapsulate the PHY device driver knowledge within PHYLIB.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:53:02 -04:00
Guillaume Nault 8349440733 l2tp: consistent reference counting in procfs and debufs
The 'pppol2tp' procfs and 'l2tp/tunnels' debugfs files handle reference
counting of sessions differently than for tunnels.

For consistency, use the same mechanism for handling both sessions and
tunnels. That is, drop the reference on the previous session just
before looking up the next one (rather than in .show()). If necessary
(if dump stops before *_next_session() returns NULL), drop the last
reference in .stop().

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:06:35 -04:00
Jon Maloy 3e5cf362c3 tipc: introduce ioctl for fetching node identity
After the introduction of a 128-bit node identity it may be difficult
for a user to correlate between this identity and the generated node
hash address.

We now try to make this easier by introducing a new ioctl() call for
fetching a node identity by using the hash value as key. This will
be particularly useful when we extend some of the commands in the
'tipc' tool, but we also expect regular user applications to need
this feature.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 11:05:41 -04:00
David S. Miller 79741a38b4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-04-27

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

The main changes are:

1) Add extensive BPF helper description into include/uapi/linux/bpf.h
   and a new script bpf_helpers_doc.py which allows for generating a
   man page out of it. Thus, every helper in BPF now comes with proper
   function signature, detailed description and return code explanation,
   from Quentin.

2) Migrate the BPF collect metadata tunnel tests from BPF samples over
   to the BPF selftests and further extend them with v6 vxlan, geneve
   and ipip tests, simplify the ipip tests, improve documentation and
   convert to bpf_ntoh*() / bpf_hton*() api, from William.

3) Currently, helpers that expect ARG_PTR_TO_MAP_{KEY,VALUE} can only
   access stack and packet memory. Extend this to allow such helpers
   to also use map values, which enabled use cases where value from
   a first lookup can be directly used as a key for a second lookup,
   from Paul.

4) Add a new helper bpf_skb_get_xfrm_state() for tc BPF programs in
   order to retrieve XFRM state information containing SPI, peer
   address and reqid values, from Eyal.

5) Various optimizations in nfp driver's BPF JIT in order to turn ADD
   and SUB instructions with negative immediate into the opposite
   operation with a positive immediate such that nfp can better fit
   small immediates into instructions. Savings in instruction count
   up to 4% have been observed, from Jakub.

6) Add the BPF prog's gpl_compatible flag to struct bpf_prog_info
   and add support for dumping this through bpftool, from Jiri.

7) Move the BPF sockmap samples over into BPF selftests instead since
   sockmap was rather a series of tests than sample anyway and this way
   this can be run from automated bots, from John.

8) Follow-up fix for bpf_adjust_tail() helper in order to make it work
   with generic XDP, from Nikita.

9) Some follow-up cleanups to BTF, namely, removing unused defines from
   BTF uapi header and renaming 'name' struct btf_* members into name_off
   to make it more clear they are offsets into string section, from Martin.

10) Remove test_sock_addr from TEST_GEN_PROGS in BPF selftests since
    not run directly but invoked from test_sock_addr.sh, from Yonghong.

11) Remove redundant ret assignment in sample BPF loader, from Wang.

12) Add couple of missing files to BPF selftest's gitignore, from Anders.

There are two trivial merge conflicts while pulling:

  1) Remove samples/sockmap/Makefile since all sockmap tests have been
     moved to selftests.
  2) Add both hunks from tools/testing/selftests/bpf/.gitignore to the
     file since git should ignore all of them.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26 21:19:50 -04:00
Wang Sheng-Hui c0885f61bb samples, bpf: remove redundant ret assignment in bpf_load_program()
2 redundant ret assignments removed:

* 'ret = 1' before the logic 'if (data_maps)', and if any errors jump to
  label 'done'. No 'ret = 1' needed before the error jump.

* After the '/* load programs */' part, if everything goes well, then
  the BPF code will be loaded and 'ret' set to 0 by load_and_attach().
  If something goes wrong, 'ret' set to none-O, the redundant 'ret = 0'
  after the for clause will make the error skipped.

  For example, if some BPF code cannot provide supported program types
  in ELF SEC("unknown"), the for clause will not call load_and_attach()
  to load the BPF code. 1 should be returned to callees instead of 0.

Signed-off-by: Wang Sheng-Hui <shhuiw@foxmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:47:06 +02:00
Daniel Borkmann a6712d45b0 Merge branch 'bpf-uapi-helper-doc'
Quentin Monnet says:

====================
eBPF helper functions can be called from within eBPF programs to perform
a variety of tasks that would be otherwise hard or impossible to do with
eBPF itself. There is a growing number of such helper functions in the
kernel, but documentation is scarce. The main user space header file
does contain a short commented description of most helpers, but it is
somewhat outdated and not complete. It is more a "cheat sheet" than a
real documentation accessible to new eBPF developers.

This commit attempts to improve the situation by replacing the existing
overview for the helpers with a more developed description. Furthermore,
a Python script is added to generate a manual page for eBPF helpers. The
workflow is the following, and requires the rst2man utility:

    $ ./scripts/bpf_helpers_doc.py \
            --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst
    $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7
    $ man /tmp/bpf-helpers.7

The objective is to keep all documentation related to the helpers in a
single place, and to be able to generate from here a manual page that
could be packaged in the man-pages repository and shipped with most
distributions.

Additionally, parsing the prototypes of the helper functions could
hopefully be reused, with a different Printer object, to generate
header files needed in some eBPF-related projects.

Regarding the description of each helper, it comprises several items:

- The function prototype.
- A description of the function and of its arguments (except for a
  couple of cases, when there are no arguments and the return value
  makes the function usage really obvious).
- A description of return values (if not void).

Additional items such as the list of compatible eBPF program and map
types for each helper, Linux kernel version that introduced the helper,
GPL-only restriction, and commit hash could be added in the future, but
it was decided on the mailing list to leave them aside for now.

For several helpers, descriptions are inspired (at times, nearly copied)
from the commit logs introducing them in the kernel--Many thanks to
their respective authors! Some sentences were also adapted from comments
from the reviews, thanks to the reviewers as well. Descriptions were
completed as much as possible, the objective being to have something easily
accessible even for people just starting with eBPF. There is probably a bit
more work to do in this direction for some helpers.

Some RST formatting is used in the descriptions (not in function
prototypes, to keep them readable, but the Python script provided in
order to generate the RST for the manual page does add formatting to
prototypes, to produce something pretty) to get "bold" and "italics" in
manual pages. Hopefully, the descriptions in bpf.h file remains
perfectly readable. Note that the few trailing white spaces are
intentional, removing them would break paragraphs for rst2man.

The descriptions should ideally be updated each time someone adds a new
helper, or updates the behaviour (new socket option supported, ...) or
the interface (new flags available, ...) of existing ones.

To ease the review process, the documentation has been split into several
patches.

v3 -> v4:
- Add a patch (#9) for newly added BPF helpers.
- Add a patch (#10) to update UAPI bpf.h version under tools/.
- Use SPDX tag in Python script.
- Several fixes on man page header and footer, and helpers documentation.
  Please refer to individual patches for details.

RFC v2 -> PATCH v3:
Several fixes on man page header and footer, and helpers documentation.
Please refer to individual patches for details.

RFC v1 -> RFC v2:
- Remove "For" (compatible program and map types), "Since" (minimal
  Linux kernel version required), "GPL only" sections and commit hashes
  for the helpers.
- Add comment on top of the description list to explain how this
  documentation is supposed to be processed.
- Update Python script accordingly (remove the same sections, and remove
  paragraphs on program types and GPL restrictions from man page
  header).
- Split series into several patches.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
2018-04-27 00:22:01 +02:00
Quentin Monnet 9cde0c8892 bpf: update bpf.h uapi header for tools
Update tools/include/uapi/linux/bpf.h file in order to reflect the
changes for BPF helper functions documentation introduced in previous
commits.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:59 +02:00
Quentin Monnet 2d020dd771 bpf: add documentation for eBPF helpers (65-66)
Add documentation for eBPF helper functions to bpf.h user header file.
This documentation can be parsed with the Python script provided in
another commit of the patch series, in order to provide a RST document
that can later be converted into a man page.

The objective is to make the documentation easily understandable and
accessible to all eBPF developers, including beginners.

This patch contains descriptions for the following helper functions:

Helper from Nikita:
- bpf_xdp_adjust_tail()

Helper from Eyal:
- bpf_skb_get_xfrm_state()

v4:
- New patch (helpers did not exist yet for previous versions).

Cc: Nikita V. Shirokov <tehnerd@tehnerd.com>
Cc: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:59 +02:00
Quentin Monnet ab12704099 bpf: add documentation for eBPF helpers (58-64)
Add documentation for eBPF helper functions to bpf.h user header file.
This documentation can be parsed with the Python script provided in
another commit of the patch series, in order to provide a RST document
that can later be converted into a man page.

The objective is to make the documentation easily understandable and
accessible to all eBPF developers, including beginners.

This patch contains descriptions for the following helper functions, all
written by John:

- bpf_redirect_map()
- bpf_sk_redirect_map()
- bpf_sock_map_update()
- bpf_msg_redirect_map()
- bpf_msg_apply_bytes()
- bpf_msg_cork_bytes()
- bpf_msg_pull_data()

v4:
- bpf_redirect_map(): Fix typos: "XDP_ABORT" changed to "XDP_ABORTED",
  "his" to "this". Also add a paragraph on performance improvement over
  bpf_redirect() helper.

v3:
- bpf_sk_redirect_map(): Improve description of BPF_F_INGRESS flag.
- bpf_msg_redirect_map(): Improve description of BPF_F_INGRESS flag.
- bpf_redirect_map(): Fix note on CPU redirection, not fully implemented
  for generic XDP but supported on native XDP.
- bpf_msg_pull_data(): Clarify comment about invalidated verifier
  checks.

Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:59 +02:00
Quentin Monnet 7aa79a869d bpf: add documentation for eBPF helpers (51-57)
Add documentation for eBPF helper functions to bpf.h user header file.
This documentation can be parsed with the Python script provided in
another commit of the patch series, in order to provide a RST document
that can later be converted into a man page.

The objective is to make the documentation easily understandable and
accessible to all eBPF developers, including beginners.

This patch contains descriptions for the following helper functions:

Helpers from Lawrence:
- bpf_setsockopt()
- bpf_getsockopt()
- bpf_sock_ops_cb_flags_set()

Helpers from Yonghong:
- bpf_perf_event_read_value()
- bpf_perf_prog_read_value()

Helper from Josef:
- bpf_override_return()

Helper from Andrey:
- bpf_bind()

v4:
- bpf_perf_event_read_value(): State that this helper should be
  preferred over bpf_perf_event_read().

v3:
- bpf_perf_event_read_value(): Fix time of selection for perf event type
  in description. Remove occurences of "cores" to avoid confusion with
  "CPU".
- bpf_bind(): Remove last paragraph of description, which was off topic.

Cc: Lawrence Brakmo <brakmo@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Yonghong Song <yhs@fb.com>
[for bpf_perf_event_read_value(), bpf_perf_prog_read_value()]
Acked-by: Andrey Ignatov <rdna@fb.com>
[for bpf_bind()]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:59 +02:00
Quentin Monnet c6b5fb8690 bpf: add documentation for eBPF helpers (42-50)
Add documentation for eBPF helper functions to bpf.h user header file.
This documentation can be parsed with the Python script provided in
another commit of the patch series, in order to provide a RST document
that can later be converted into a man page.

The objective is to make the documentation easily understandable and
accessible to all eBPF developers, including beginners.

This patch contains descriptions for the following helper functions:

Helper from Kaixu:
- bpf_perf_event_read()

Helpers from Martin:
- bpf_skb_under_cgroup()
- bpf_xdp_adjust_head()

Helpers from Sargun:
- bpf_probe_write_user()
- bpf_current_task_under_cgroup()

Helper from Thomas:
- bpf_skb_change_head()

Helper from Gianluca:
- bpf_probe_read_str()

Helpers from Chenbo:
- bpf_get_socket_cookie()
- bpf_get_socket_uid()

v4:
- bpf_perf_event_read(): State that bpf_perf_event_read_value() should
  be preferred over this helper.
- bpf_skb_change_head(): Clarify comment about invalidated verifier
  checks.
- bpf_xdp_adjust_head(): Clarify comment about invalidated verifier
  checks.
- bpf_probe_write_user(): Add that dst must be a valid user space
  address.
- bpf_get_socket_cookie(): Improve description by making clearer that
  the cockie belongs to the socket, and state that it remains stable for
  the life of the socket.

v3:
- bpf_perf_event_read(): Fix time of selection for perf event type in
  description. Remove occurences of "cores" to avoid confusion with
  "CPU".

Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Gianluca Borello <g.borello@gmail.com>
Cc: Chenbo Feng <fengc@google.com>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
[for bpf_skb_under_cgroup(), bpf_xdp_adjust_head()]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:59 +02:00
Quentin Monnet fa15601ab3 bpf: add documentation for eBPF helpers (33-41)
Add documentation for eBPF helper functions to bpf.h user header file.
This documentation can be parsed with the Python script provided in
another commit of the patch series, in order to provide a RST document
that can later be converted into a man page.

The objective is to make the documentation easily understandable and
accessible to all eBPF developers, including beginners.

This patch contains descriptions for the following helper functions, all
written by Daniel:

- bpf_get_hash_recalc()
- bpf_skb_change_tail()
- bpf_skb_pull_data()
- bpf_csum_update()
- bpf_set_hash_invalid()
- bpf_get_numa_node_id()
- bpf_set_hash()
- bpf_skb_adjust_room()
- bpf_xdp_adjust_meta()

v4:
- bpf_skb_change_tail(): Clarify comment about invalidated verifier
  checks.
- bpf_skb_pull_data(): Clarify the motivation for using this helper or
  bpf_skb_load_bytes(), on non-linear buffers. Fix RST formatting for
  *skb*. Clarify comment about invalidated verifier checks.
- bpf_csum_update(): Fix description of checksum (entire packet, not IP
  checksum). Fix a typo: "header" instead of "helper".
- bpf_set_hash_invalid(): Mention bpf_get_hash_recalc().
- bpf_get_numa_node_id(): State that the helper is not restricted to
  programs attached to sockets.
- bpf_skb_adjust_room(): Clarify comment about invalidated verifier
  checks.
- bpf_xdp_adjust_meta(): Clarify comment about invalidated verifier
  checks.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:59 +02:00
Quentin Monnet 1fdd08bedc bpf: add documentation for eBPF helpers (23-32)
Add documentation for eBPF helper functions to bpf.h user header file.
This documentation can be parsed with the Python script provided in
another commit of the patch series, in order to provide a RST document
that can later be converted into a man page.

The objective is to make the documentation easily understandable and
accessible to all eBPF developers, including beginners.

This patch contains descriptions for the following helper functions, all
written by Daniel:

- bpf_get_prandom_u32()
- bpf_get_smp_processor_id()
- bpf_get_cgroup_classid()
- bpf_get_route_realm()
- bpf_skb_load_bytes()
- bpf_csum_diff()
- bpf_skb_get_tunnel_opt()
- bpf_skb_set_tunnel_opt()
- bpf_skb_change_proto()
- bpf_skb_change_type()

v4:
- bpf_get_prandom_u32(): Warn that the prng is not cryptographically
  secure.
- bpf_get_smp_processor_id(): Fix a typo (case).
- bpf_get_cgroup_classid(): Clarify description. Add notes on the helper
  being limited to cgroup v1, and to egress path.
- bpf_get_route_realm(): Add comparison with bpf_get_cgroup_classid().
  Add a note about usage with TC and advantage of clsact. Fix a typo in
  return value ("sdb" instead of "skb").
- bpf_skb_load_bytes(): Make explicit loading large data loads it to the
  eBPF stack.
- bpf_csum_diff(): Add a note on seed that can be cascaded. Link to
  bpf_l3|l4_csum_replace().
- bpf_skb_get_tunnel_opt(): Add a note about usage with "collect
  metadata" mode, and example of this with Geneve.
- bpf_skb_set_tunnel_opt(): Add a link to bpf_skb_get_tunnel_opt()
  description.
- bpf_skb_change_proto(): Mention that the main use case is NAT64.
  Clarify comment about invalidated verifier checks.

v3:
- bpf_get_prandom_u32(): Fix helper name :(. Add description, including
  a note on the internal random state.
- bpf_get_smp_processor_id(): Add description, including a note on the
  processor id remaining stable during program run.
- bpf_get_cgroup_classid(): State that CONFIG_CGROUP_NET_CLASSID is
  required to use the helper. Add a reference to related documentation.
  State that placing a task in net_cls controller disables cgroup-bpf.
- bpf_get_route_realm(): State that CONFIG_CGROUP_NET_CLASSID is
  required to use this helper.
- bpf_skb_load_bytes(): Fix comment on current use cases for the helper.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:59 +02:00
Quentin Monnet c456dec4d2 bpf: add documentation for eBPF helpers (12-22)
Add documentation for eBPF helper functions to bpf.h user header file.
This documentation can be parsed with the Python script provided in
another commit of the patch series, in order to provide a RST document
that can later be converted into a man page.

The objective is to make the documentation easily understandable and
accessible to all eBPF developers, including beginners.

This patch contains descriptions for the following helper functions, all
written by Alexei:

- bpf_get_current_pid_tgid()
- bpf_get_current_uid_gid()
- bpf_get_current_comm()
- bpf_skb_vlan_push()
- bpf_skb_vlan_pop()
- bpf_skb_get_tunnel_key()
- bpf_skb_set_tunnel_key()
- bpf_redirect()
- bpf_perf_event_output()
- bpf_get_stackid()
- bpf_get_current_task()

v4:
- bpf_redirect(): Fix typo: "XDP_ABORT" changed to "XDP_ABORTED". Add
  note on bpf_redirect_map() providing better performance. Replace "Save
  for" with "Except for".
- bpf_skb_vlan_push(): Clarify comment about invalidated verifier
  checks.
- bpf_skb_vlan_pop(): Clarify comment about invalidated verifier
  checks.
- bpf_skb_get_tunnel_key(): Add notes on tunnel_id, "collect metadata"
  mode, and example tunneling protocols with which it can be used.
- bpf_skb_set_tunnel_key(): Add a reference to the description of
  bpf_skb_get_tunnel_key().
- bpf_perf_event_output(): Specify that, and for what purpose, the
  helper can be used with programs attached to TC and XDP.

v3:
- bpf_skb_get_tunnel_key(): Change and improve description and example.
- bpf_redirect(): Improve description of BPF_F_INGRESS flag.
- bpf_perf_event_output(): Fix first sentence of description. Delete
  wrong statement on context being evaluated as a struct pt_reg. Remove
  the long yet incomplete example.
- bpf_get_stackid(): Add a note about PERF_MAX_STACK_DEPTH being
  configurable.

Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:58 +02:00
Quentin Monnet ad4a522349 bpf: add documentation for eBPF helpers (01-11)
Add documentation for eBPF helper functions to bpf.h user header file.
This documentation can be parsed with the Python script provided in
another commit of the patch series, in order to provide a RST document
that can later be converted into a man page.

The objective is to make the documentation easily understandable and
accessible to all eBPF developers, including beginners.

This patch contains descriptions for the following helper functions, all
written by Alexei:

- bpf_map_lookup_elem()
- bpf_map_update_elem()
- bpf_map_delete_elem()
- bpf_probe_read()
- bpf_ktime_get_ns()
- bpf_trace_printk()
- bpf_skb_store_bytes()
- bpf_l3_csum_replace()
- bpf_l4_csum_replace()
- bpf_tail_call()
- bpf_clone_redirect()

v4:
- bpf_map_lookup_elem(): Add "const" qualifier for key.
- bpf_map_update_elem(): Add "const" qualifier for key and value.
- bpf_map_lookup_elem(): Add "const" qualifier for key.
- bpf_skb_store_bytes(): Clarify comment about invalidated verifier
  checks.
- bpf_l3_csum_replace(): Mention L3 instead of just IP, and add a note
  about bpf_csum_diff().
- bpf_l4_csum_replace(): Mention L4 instead of just TCP/UDP, and add a
  note about bpf_csum_diff().
- bpf_tail_call(): Bring minor edits to description.
- bpf_clone_redirect(): Add a note about the relation with
  bpf_redirect(). Also clarify comment about invalidated verifier
  checks.

v3:
- bpf_map_lookup_elem(): Fix description of restrictions for flags
  related to the existence of the entry.
- bpf_trace_printk(): State that trace_pipe can be configured. Fix
  return value in case an unknown format specifier is met. Add a note on
  kernel log notice when the helper is used. Edit example.
- bpf_tail_call(): Improve comment on stack inheritance.
- bpf_clone_redirect(): Improve description of BPF_F_INGRESS flag.

Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:58 +02:00
Quentin Monnet 56a092c895 bpf: add script and prepare bpf.h for new helpers documentation
Remove previous "overview" of eBPF helpers from user bpf.h header.
Replace it by a comment explaining how to process the new documentation
(to come in following patches) with a Python script to produce RST, then
man page documentation.

Also add the aforementioned Python script under scripts/. It is used to
process include/uapi/linux/bpf.h and to extract helper descriptions, to
turn it into a RST document that can further be processed with rst2man
to produce a man page. The script takes one "--filename <path/to/file>"
option. If the script is launched from scripts/ in the kernel root
directory, it should be able to find the location of the header to
parse, and "--filename <path/to/file>" is then optional. If it cannot
find the file, then the option becomes mandatory. RST-formatted
documentation is printed to standard output.

Typical workflow for producing the final man page would be:

    $ ./scripts/bpf_helpers_doc.py \
            --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst
    $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7
    $ man /tmp/bpf-helpers.7

Note that the tool kernel-doc cannot be used to document eBPF helpers,
whose signatures are not available directly in the header files
(pre-processor directives are used to produce them at the beginning of
the compilation process).

v4:
- Also remove overviews for newly added bpf_xdp_adjust_tail() and
  bpf_skb_get_xfrm_state().
- Remove vague statement about what helpers are restricted to GPL
  programs in "LICENSE" section for man page footer.
- Replace license boilerplate with SPDX tag for Python script.

v3:
- Change license for man page.
- Remove "for safety reasons" from man page header text.
- Change "packets metadata" to "packets" in man page header text.
- Move and fix comment on helpers introducing no overhead.
- Remove "NOTES" section from man page footer.
- Add "LICENSE" section to man page footer.
- Edit description of file include/uapi/linux/bpf.h in man page footer.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:21:58 +02:00
Daniel Borkmann 3f13de6d6f Merge branch 'bpf-tunnel-metadata-selftests'
William Tu says:

====================
The patch series provide end-to-end eBPF tunnel testsute.  A common topology
is created below for all types of tunnels:

Topology:
---------
     root namespace   |     at_ns0 namespace
                      |
      -----------     |     -----------
      | tnl dev |     |     | tnl dev |  (overlay network)
      -----------     |     -----------
      metadata-mode   |     native-mode
       with bpf       |
                      |
      ----------      |     ----------
      |  veth1  | --------- |  veth0  |  (underlay network)
      ----------    peer    ----------

Device Configuration
--------------------
 Root namespace with metadata-mode tunnel + BPF
 Device names and addresses:
       veth1 IP: 172.16.1.200, IPv6: 00::22 (underlay)
       tunnel dev <type>11, ex: gre11, IPv4: 10.1.1.200 (overlay)

 Namespace at_ns0 with native tunnel
 Device names and addresses:
       veth0 IPv4: 172.16.1.100, IPv6: 00::11 (underlay)
       tunnel dev <type>00, ex: gre00, IPv4: 10.1.1.100 (overlay)

End-to-end ping packet flow
---------------------------
 Most of the tests start by namespace creation, device configuration,
 then ping the underlay and overlay network.  When doing 'ping 10.1.1.100'
 from root namespace, the following operations happen:
 1) Route lookup shows 10.1.1.100/24 belongs to tnl dev, fwd to tnl dev.
 2) Tnl device's egress BPF program is triggered and set the tunnel metadata,
    with remote_ip=172.16.1.200 and others.
 3) Outer tunnel header is prepended and route the packet to veth1's egress
 4) veth0's ingress queue receive the tunneled packet at namespace at_ns0
 5) Tunnel protocol handler, ex: vxlan_rcv, decap the packet
 6) Forward the packet to the overlay tnl dev

Test Cases
-----------------------------
 Tunnel Type |  BPF Programs
-----------------------------
 GRE:          gre_set_tunnel, gre_get_tunnel
 IP6GRE:       ip6gretap_set_tunnel, ip6gretap_get_tunnel
 ERSPAN:       erspan_set_tunnel, erspan_get_tunnel
 IP6ERSPAN:    ip4ip6erspan_set_tunnel, ip4ip6erspan_get_tunnel
 VXLAN:        vxlan_set_tunnel, vxlan_get_tunnel
 IP6VXLAN:     ip6vxlan_set_tunnel, ip6vxlan_get_tunnel
 GENEVE:       geneve_set_tunnel, geneve_get_tunnel
 IP6GENEVE:    ip6geneve_set_tunnel, ip6geneve_get_tunnel
 IPIP:         ipip_set_tunnel, ipip_get_tunnel
 IP6IP:        ipip6_set_tunnel, ipip6_get_tunnel,
               ip6ip6_set_tunnel, ip6ip6_get_tunnel
 XFRM:         xfrm_get_state
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:11:16 +02:00
William Tu b05cd74043 samples/bpf: remove the bpf tunnel testsuite.
Move the testsuite to
selftests/bpf/{test_tunnel_kern.c, test_tunnel.sh}

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:11:15 +02:00
William Tu 933a741e3b selftests/bpf: bpf tunnel test.
The patch migrates the original tests at samples/bpf/tcbpf2_kern.c
and samples/bpf/test_tunnel_bpf.sh to selftests.  There are a couple
changes from the original:
    1) add ipv6 vxlan, ipv6 geneve, ipv6 ipip tests
    2) simplify the original ipip tests (remove iperf tests)
    3) improve documentation
    4) use bpf_ntoh* and bpf_hton* api

In summary, 'test_tunnel_kern.o' contains the following bpf program:
  GRE: gre_set_tunnel, gre_get_tunnel
  IP6GRE: ip6gretap_set_tunnel, ip6gretap_get_tunnel
  ERSPAN: erspan_set_tunnel, erspan_get_tunnel
  IP6ERSPAN: ip4ip6erspan_set_tunnel, ip4ip6erspan_get_tunnel
  VXLAN: vxlan_set_tunnel, vxlan_get_tunnel
  IP6VXLAN: ip6vxlan_set_tunnel, ip6vxlan_get_tunnel
  GENEVE: geneve_set_tunnel, geneve_get_tunnel
  IP6GENEVE: ip6geneve_set_tunnel, ip6geneve_get_tunnel
  IPIP: ipip_set_tunnel, ipip_get_tunnel
  IP6IP: ipip6_set_tunnel, ipip6_get_tunnel,
         ip6ip6_set_tunnel, ip6ip6_get_tunnel
  XFRM: xfrm_get_state

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-27 00:11:14 +02:00
Nikita V. Shirokov f761312023 bpf: fix xdp_generic for bpf_adjust_tail usecase
When bpf_adjust_tail was introduced for generic xdp, it changed skb's tail
pointer, so it was pointing to the new "end of the packet". However skb's
len field wasn't properly modified, so on the wire ethernet frame had
original (or even bigger, if adjust_head was used) size. This diff is
fixing this.

Fixes: 198d83bb3 (" bpf: make generic xdp compatible w/ bpf_xdp_adjust_tail")
Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-26 22:56:40 +02:00
Jiri Olsa 9b984a20ca tools, bpftool: Display license GPL compatible in prog show/list
Display the license "gpl" string in bpftool prog command, like:

  # bpftool prog list
  5: tracepoint  name func  tag 57cd311f2e27366b  gpl
          loaded_at Apr 26/09:37  uid 0
          xlated 16B  not jited  memlock 4096B

  # bpftool --json --pretty prog show
  [{
          "id": 5,
          "type": "tracepoint",
          "name": "func",
          "tag": "57cd311f2e27366b",
          "gpl_compatible": true,
          "loaded_at": "Apr 26/09:37",
          "uid": 0,
          "bytes_xlated": 16,
          "jited": false,
          "bytes_memlock": 4096
      }
  ]

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-26 22:39:22 +02:00
Jiri Olsa fb6ef42b5c tools, bpf: Sync bpf.h uapi header
Syncing the bpf.h uapi header with tools.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-26 22:38:38 +02:00
Jiri Olsa b85fab0e67 bpf: Add gpl_compatible flag to struct bpf_prog_info
Adding gpl_compatible flag to struct bpf_prog_info
so it can be dumped via bpf_prog_get_info_by_fd and
displayed via bpftool progs dump.

Alexei noticed 4-byte hole in struct bpf_prog_info,
so we put the u32 flags field in there, and we can
keep adding bit fields in there without breaking
user space.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-26 22:36:11 +02:00
David S. Miller cb586c63e3 Merge branch 'udp-gso'
Willem de Bruijn says:

====================
udp gso

Segmentation offload reduces cycles/byte for large packets by
amortizing the cost of protocol stack traversal.

This patchset implements GSO for UDP. A process can concatenate and
submit multiple datagrams to the same destination in one send call
by setting socket option SOL_UDP/UDP_SEGMENT with the segment size,
or passing an analogous cmsg at send time.

The stack will send the entire large (up to network layer max size)
datagram through the protocol layer. At the GSO layer, it is broken
up in individual segments. All receive the same network layer header
and UDP src and dst port. All but the last segment have the same UDP
header, but the last may differ in length and checksum.

Initial results show a significant reduction in UDP cycles/byte.
See the main patch for more details and benchmark results.

        udp
          876 MB/s 14873 msg/s 624666 calls/s
            11,205,777,429      cycles

        udp gso
         2139 MB/s 36282 msg/s 36282 calls/s
            11,204,374,561      cycles

The patch set is broken down as follows:
- patch 1 is a prerequisite: code rearrangement, noop otherwise
- patch 2 implements the gso logic
- patch 3 adds protocol stack support for UDP_SEGMENT
- patch 4,5,7 are refinements
- patch 6 adds the cmsg interface
- patch 8..11 are tests

This idea was presented previously at netconf 2017-2
http://vger.kernel.org/netconf2017_files/rx_hardening_and_udp_gso.pdf

Changes v1 -> v2
  - Convert __udp_gso_segment to modify headers after skb_segment
  - Split main patch into two, one for gso logic, one for UDP_SEGMENT

Changes RFC -> v1
  - MSG_MORE:
      fixed, by allowing checksum offload with corking if gso
  - SKB_GSO_UDP_L4:
      made independent from SKB_GSO_UDP
      and removed skb_is_ufo() wrapper
  - NETIF_F_GSO_UDP_L4:
      add to netdev_features_string
      and to netdev-features.txt
      add BUILD_BUG_ON to match SKB_GSO_UDP_L4 value
  - UDP_MAX_SEGMENTS:
      introduce limit on number of segments per gso skb
      to avoid extreme cases like IP_MAX_MTU/IPV4_MIN_MTU
  - CHECKSUM_PARTIAL:
      test against missing feature after ndo_features_check
      if not supported return error, analogous to udp_send_check
  - MSG_ZEROCOPY: removed, deferred for now
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26 15:10:06 -04:00