Commit Graph

753706 Commits

Author SHA1 Message Date
Linus Torvalds
bb609316d4 Merge branch 'parisc-4.17-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc fixes from Helge Deller:
 "Fix two section mismatches, convert to read_persistent_clock64(), add
  further documentation regarding the HPMC crash handler and make
  bzImage the default build target"

* 'parisc-4.17-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Fix section mismatches
  parisc: drivers.c: Fix section mismatches
  parisc: time: Convert read_persistent_clock() to read_persistent_clock64()
  parisc: Document rules regarding checksum of HPMC handler
  parisc: Make bzImage default build target
2018-05-03 18:31:19 -10:00
Alexei Starovoitov
5234ccf2be Merge branch 'move-ld_abs-to-native-BPF'
Daniel Borkmann says:

====================
This set simplifies BPF JITs significantly by moving ld_abs/ld_ind
to native BPF, for details see individual patches. Main rationale
is in patch 'implement ld_abs/ld_ind in native bpf'. Thanks!

v1 -> v2:
  - Added missing seen_lds_abs in LDX_MSH and use X = A
    initially due to being preserved on func call.
  - Added a large batch of cBPF tests into test_bpf.
  - Added x32 removal of LD_ABS/LD_IND, so all JITs are
    covered.
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:22 -07:00
Daniel Borkmann
32b3652c30 bpf: sync tools bpf.h uapi header
Only sync the header from include/uapi/linux/bpf.h.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann
24dea04767 bpf, x32: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from x32 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann
e1cf4befa2 bpf, s390x: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from s390x JIT.
Tested on s390x instance on LinuxONE.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann
dbf44daf7c bpf, ppc64: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from ppc64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann
4db25cc988 bpf, mips64: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from mips64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann
0d2d0cedc0 bpf, arm32: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from arm32 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann
fe83963b7c bpf, sparc64: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from sparc64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann
816d9ef32a bpf, arm64: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from arm64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Daniel Borkmann
e782bdcf58 bpf, x64: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from x64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Daniel Borkmann
4e1ec56cdc bpf: add skb_load_bytes_relative helper
This adds a small BPF helper similar to bpf_skb_load_bytes() that
is able to load relative to mac/net header offset from the skb's
linear data. Compared to bpf_skb_load_bytes(), it takes a fifth
argument namely start_header, which is either BPF_HDR_START_MAC
or BPF_HDR_START_NET. This allows for a more flexible alternative
compared to LD_ABS/LD_IND with negative offset. It's enabled for
tc BPF programs as well as sock filter program types where it's
mainly useful in reuseport programs to ease access to lower header
data.

Reference: https://lists.iovisor.org/pipermail/iovisor-dev/2017-March/000698.html
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Daniel Borkmann
e0cea7ce98 bpf: implement ld_abs/ld_ind in native bpf
The main part of this work is to finally allow removal of LD_ABS
and LD_IND from the BPF core by reimplementing them through native
eBPF instead. Both LD_ABS/LD_IND were carried over from cBPF and
keeping them around in native eBPF caused way more trouble than
actually worth it. To just list some of the security issues in
the past:

  * fdfaf64e75 ("x86: bpf_jit: support negative offsets")
  * 35607b02db ("sparc: bpf_jit: fix loads from negative offsets")
  * e0ee9c1215 ("x86: bpf_jit: fix two bugs in eBPF JIT compiler")
  * 07aee94394 ("bpf, sparc: fix usage of wrong reg for load_skb_regs after call")
  * 6d59b7dbf7 ("bpf, s390x: do not reload skb pointers in non-skb context")
  * 87338c8e2c ("bpf, ppc64: do not reload skb pointers in non-skb context")

For programs in native eBPF, LD_ABS/LD_IND are pretty much legacy
these days due to their limitations and more efficient/flexible
alternatives that have been developed over time such as direct
packet access. LD_ABS/LD_IND only cover 1/2/4 byte loads into a
register, the load happens in host endianness and its exception
handling can yield unexpected behavior. The latter is explained
in depth in f6b1b3bf0d ("bpf: fix subprog verifier bypass by
div/mod by 0 exception") with similar cases of exceptions we had.
In native eBPF more recent program types will disable LD_ABS/LD_IND
altogether through may_access_skb() in verifier, and given the
limitations in terms of exception handling, it's also disabled
in programs that use BPF to BPF calls.

In terms of cBPF, the LD_ABS/LD_IND is used in networking programs
to access packet data. It is not used in seccomp-BPF but programs
that use it for socket filtering or reuseport for demuxing with
cBPF. This is mostly relevant for applications that have not yet
migrated to native eBPF.

The main complexity and source of bugs in LD_ABS/LD_IND is coming
from their implementation in the various JITs. Most of them keep
the model around from cBPF times by implementing a fastpath written
in asm. They use typically two from the BPF program hidden CPU
registers for caching the skb's headlen (skb->len - skb->data_len)
and skb->data. Throughout the JIT phase this requires to keep track
whether LD_ABS/LD_IND are used and if so, the two registers need
to be recached each time a BPF helper would change the underlying
packet data in native eBPF case. At least in eBPF case, available
CPU registers are rare and the additional exit path out of the
asm written JIT helper makes it also inflexible since not all
parts of the JITer are in control from plain C. A LD_ABS/LD_IND
implementation in eBPF therefore allows to significantly reduce
the complexity in JITs with comparable performance results for
them, e.g.:

test_bpf             tcpdump port 22             tcpdump complex
x64      - before    15 21 10                    14 19  18
         - after      7 10 10                     7 10  15
arm64    - before    40 91 92                    40 91 151
         - after     51 64 73                    51 62 113

For cBPF we now track any usage of LD_ABS/LD_IND in bpf_convert_filter()
and cache the skb's headlen and data in the cBPF prologue. The
BPF_REG_TMP gets remapped from R8 to R2 since it's mainly just
used as a local temporary variable. This allows to shrink the
image on x86_64 also for seccomp programs slightly since mapping
to %rsi is not an ereg. In callee-saved R8 and R9 we now track
skb data and headlen, respectively. For normal prologue emission
in the JITs this does not add any extra instructions since R8, R9
are pushed to stack in any case from eBPF side. cBPF uses the
convert_bpf_ld_abs() emitter which probes the fast path inline
already and falls back to bpf_skb_load_helper_{8,16,32}() helper
relying on the cached skb data and headlen as well. R8 and R9
never need to be reloaded due to bpf_helper_changes_pkt_data()
since all skb access in cBPF is read-only. Then, for the case
of native eBPF, we use the bpf_gen_ld_abs() emitter, which calls
the bpf_skb_load_helper_{8,16,32}_no_cache() helper unconditionally,
does neither cache skb data and headlen nor has an inlined fast
path. The reason for the latter is that native eBPF does not have
any extra registers available anyway, but even if there were, it
avoids any reload of skb data and headlen in the first place.
Additionally, for the negative offsets, we provide an alternative
bpf_skb_load_bytes_relative() helper in eBPF which operates
similarly as bpf_skb_load_bytes() and allows for more flexibility.
Tested myself on x64, arm64, s390x, from Sandipan on ppc64.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Daniel Borkmann
93731ef086 bpf: migrate ebpf ld_abs/ld_ind tests to test_verifier
Remove all eBPF tests involving LD_ABS/LD_IND from test_bpf.ko. Reason
is that the eBPF tests from test_bpf module do not go via BPF verifier
and therefore any instruction rewrites from verifier cannot take place.

Therefore, move them into test_verifier which runs out of user space,
so that verfier can rewrite LD_ABS/LD_IND internally in upcoming patches.
It will have the same effect since runtime tests are also performed from
there. This also allows to finally unexport bpf_skb_vlan_{push,pop}_proto
and keep it internal to core kernel.

Additionally, also add further cBPF LD_ABS/LD_IND test coverage into
test_bpf.ko suite.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Daniel Borkmann
b390134c24 bpf: prefix cbpf internal helpers with bpf_
No change in functionality, just remove the '__' prefix and replace it
with a 'bpf_' prefix instead. We later on add a couple of more helpers
for cBPF and keeping the scheme with '__' is suboptimal there.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Alexei Starovoitov
08dbc7a66a Merge branch 'AF_XDP-initial-support'
Björn Töpel says:

====================
This patch set introduces a new address family called AF_XDP that is
optimized for high performance packet processing and, in upcoming
patch sets, zero-copy semantics. In this patch set, we have removed
all zero-copy related code in order to make it smaller, simpler and
hopefully more review friendly. This patch set only supports copy-mode
for the generic XDP path (XDP_SKB) for both RX and TX and copy-mode
for RX using the XDP_DRV path. Zero-copy support requires XDP and
driver changes that Jesper Dangaard Brouer is working on. Some of his
work has already been accepted. We will publish our zero-copy support
for RX and TX on top of his patch sets at a later point in time.

An AF_XDP socket (XSK) is created with the normal socket()
syscall. Associated with each XSK are two queues: the RX queue and the
TX queue. A socket can receive packets on the RX queue and it can send
packets on the TX queue. These queues are registered and sized with
the setsockopts XDP_RX_RING and XDP_TX_RING, respectively. It is
mandatory to have at least one of these queues for each socket. In
contrast to AF_PACKET V2/V3 these descriptor queues are separated from
packet buffers. An RX or TX descriptor points to a data buffer in a
memory area called a UMEM. RX and TX can share the same UMEM so that a
packet does not have to be copied between RX and TX. Moreover, if a
packet needs to be kept for a while due to a possible retransmit, the
descriptor that points to that packet can be changed to point to
another and reused right away. This again avoids copying data.

This new dedicated packet buffer area is call a UMEM. It consists of a
number of equally size frames and each frame has a unique frame id. A
descriptor in one of the queues references a frame by referencing its
frame id. The user space allocates memory for this UMEM using whatever
means it feels is most appropriate (malloc, mmap, huge pages,
etc). This memory area is then registered with the kernel using the new
setsockopt XDP_UMEM_REG. The UMEM also has two queues: the FILL queue
and the COMPLETION queue. The fill queue is used by the application to
send down frame ids for the kernel to fill in with RX packet
data. References to these frames will then appear in the RX queue of
the XSK once they have been received. The completion queue, on the
other hand, contains frame ids that the kernel has transmitted
completely and can now be used again by user space, for either TX or
RX. Thus, the frame ids appearing in the completion queue are ids that
were previously transmitted using the TX queue. In summary, the RX and
FILL queues are used for the RX path and the TX and COMPLETION queues
are used for the TX path.

The socket is then finally bound with a bind() call to a device and a
specific queue id on that device, and it is not until bind is
completed that traffic starts to flow. Note that in this patch set,
all packet data is copied out to user-space.

A new feature in this patch set is that the UMEM can be shared between
processes, if desired. If a process wants to do this, it simply skips
the registration of the UMEM and its corresponding two queues, sets a
flag in the bind call and submits the XSK of the process it would like
to share UMEM with as well as its own newly created XSK socket. The
new process will then receive frame id references in its own RX queue
that point to this shared UMEM. Note that since the queue structures
are single-consumer / single-producer (for performance reasons), the
new process has to create its own socket with associated RX and TX
queues, since it cannot share this with the other process. This is
also the reason that there is only one set of FILL and COMPLETION
queues per UMEM. It is the responsibility of a single process to
handle the UMEM. If multiple-producer / multiple-consumer queues are
implemented in the future, this requirement could be relaxed.

How is then packets distributed between these two XSK? We have
introduced a new BPF map called XSKMAP (or BPF_MAP_TYPE_XSKMAP in
full). The user-space application can place an XSK at an arbitrary
place in this map. The XDP program can then redirect a packet to a
specific index in this map and at this point XDP validates that the
XSK in that map was indeed bound to that device and queue number. If
not, the packet is dropped. If the map is empty at that index, the
packet is also dropped. This also means that it is currently mandatory
to have an XDP program loaded (and one XSK in the XSKMAP) to be able
to get any traffic to user space through the XSK.

AF_XDP can operate in two different modes: XDP_SKB and XDP_DRV. If the
driver does not have support for XDP, or XDP_SKB is explicitly chosen
when loading the XDP program, XDP_SKB mode is employed that uses SKBs
together with the generic XDP support and copies out the data to user
space. A fallback mode that works for any network device. On the other
hand, if the driver has support for XDP, it will be used by the AF_XDP
code to provide better performance, but there is still a copy of the
data into user space.

There is a xdpsock benchmarking/test application included that
demonstrates how to use AF_XDP sockets with both private and shared
UMEMs. Say that you would like your UDP traffic from port 4242 to end
up in queue 16, that we will enable AF_XDP on. Here, we use ethtool
for this:

      ethtool -N p3p2 rx-flow-hash udp4 fn
      ethtool -N p3p2 flow-type udp4 src-port 4242 dst-port 4242 \
          action 16

Running the rxdrop benchmark in XDP_DRV mode can then be done
using:

      samples/bpf/xdpsock -i p3p2 -q 16 -r -N

For XDP_SKB mode, use the switch "-S" instead of "-N" and all options
can be displayed with "-h", as usual.

We have run some benchmarks on a dual socket system with two Broadwell
E5 2660 @ 2.0 GHz with hyperthreading turned off. Each socket has 14
cores which gives a total of 28, but only two cores are used in these
experiments. One for TR/RX and one for the user space application. The
memory is DDR4 @ 2133 MT/s (1067 MHz) and the size of each DIMM is
8192MB and with 8 of those DIMMs in the system we have 64 GB of total
memory. The compiler used is gcc (Ubuntu 7.3.0-16ubuntu3) 7.3.0. The
NIC is Intel I40E 40Gbit/s using the i40e driver.

Below are the results in Mpps of the I40E NIC benchmark runs for 64
and 1500 byte packets, generated by a commercial packet generator HW
outputing packets at full 40 Gbit/s line rate. The results are without
retpoline so that we can compare against previous numbers. With
retpoline, the AF_XDP numbers drop with between 10 - 15 percent.

AF_XDP performance 64 byte packets. Results from V2 in parenthesis.
Benchmark   XDP_SKB   XDP_DRV
rxdrop       2.9(3.0)   9.6(9.5)
txpush       2.6(2.5)   NA*
l2fwd        1.9(1.9)   2.5(2.5) (TX using XDP_SKB in both cases)

AF_XDP performance 1500 byte packets:
Benchmark   XDP_SKB   XDP_DRV
rxdrop       2.1(2.2)   3.3(3.3)
l2fwd        1.4(1.4)   1.8(1.8) (TX using XDP_SKB in both cases)

* NA since we have no support for TX using the XDP_DRV infrastructure
  in this patch set. This is for a future patch set since it involves
  changes to the XDP NDOs. Some of this has been upstreamed by Jesper
  Dangaard Brouer.

XDP performance on our system as a base line:

64 byte packets:
XDP stats       CPU     pps         issue-pps
XDP-RX CPU      16      32.3(32.9)M  0

1500 byte packets:
XDP stats       CPU     pps         issue-pps
XDP-RX CPU      16      3.3(3.3)M    0

Changes from V2:

* Fixed a race in XSKMAP map found by Will. The code has been
  completely rearchitected and is now simpler, faster, and hopefully
  also not racy. Please review and check if it holds.

If you would like to diff V2 against V3, you can find them here:
https://github.com/bjoto/linux/tree/af-xdp-v2-on-bpf-next
https://github.com/bjoto/linux/tree/af-xdp-v3-on-bpf-next

The structure of the patch set is as follows:

Patches 1-3: Basic socket and umem plumbing
Patches 4-9: RX support together with the new XSKMAP
Patches 10-13: TX support
Patch 14: Statistics support with getsockopt()
Patch 15: Sample application

We based this patch set on bpf-next commit a3fe1f6f2a ("tools:
bpftool: change time format for program 'loaded at:' information")

To do for this patch set:

* Syzkaller torture session being worked on

Post-series plan:

* Optimize performance

* Kernel selftest

* Kernel load module support of AF_XDP would be nice. Unclear how to
  achieve this though since our XDP code depends on net/core.

* Support for AF_XDP sockets without an XPD program loaded. In this
  case all the traffic on a queue should go up to the user space socket.

* Daniel Borkmann's suggestion for a "copy to XDP socket, and return
  XDP_PASS" for a tcpdump-like functionality.

* And of course getting to zero-copy support in small increments,
  starting with TX then adding RX.

Thanks: Björn and Magnus
====================

Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:21:21 -07:00
Magnus Karlsson
b4b8faa1de samples/bpf: sample application and documentation for AF_XDP sockets
This is a sample application for AF_XDP sockets. The application
supports three different modes of operation: rxdrop, txonly and l2fwd.

To show-case a simple round-robin load-balancing between a set of
sockets in an xskmap, set the RR_LB compile time define option to 1 in
"xdpsock.h".

v2: The entries variable was calculated twice in {umem,xq}_nb_avail.

Co-authored-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:25 -07:00
Magnus Karlsson
af75d9e02d xsk: statistics support
In this commit, a new getsockopt is added: XDP_STATISTICS. This is
used to obtain stats from the sockets.

v2: getsockopt now returns size of stats structure.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:25 -07:00
Magnus Karlsson
35fcde7f8d xsk: support for Tx
Here, Tx support is added. The user fills the Tx queue with frames to
be sent by the kernel, and let's the kernel know using the sendmsg
syscall.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:25 -07:00
Magnus Karlsson
865b03f211 dev: packet: make packet_direct_xmit a common function
The new dev_direct_xmit will be used by AF_XDP in later commits.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Magnus Karlsson
f61459030e xsk: add Tx queue setup and mmap support
Another setsockopt (XDP_TX_QUEUE) is added to let the process allocate
a queue, where the user process can pass frames to be transmitted by
the kernel.

The mmapping of the queue is done using the XDP_PGOFF_TX_QUEUE offset.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Magnus Karlsson
fe2308328c xsk: add umem completion queue support and mmap
Here, we add another setsockopt for registered user memory (umem)
called XDP_UMEM_COMPLETION_QUEUE. Using this socket option, the
process can ask the kernel to allocate a queue (ring buffer) and also
mmap it (XDP_UMEM_PGOFF_COMPLETION_QUEUE) into the process.

The queue is used to explicitly pass ownership of umem frames from the
kernel to user process. This will be used by the TX path to tell user
space that a certain frame has been transmitted and user space can use
it for something else, if it wishes.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Björn Töpel
02671e23e7 xsk: wire up XDP_SKB side of AF_XDP
This commit wires up the xskmap to XDP_SKB layer.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Björn Töpel
1b1a251c83 xsk: wire up XDP_DRV side of AF_XDP
This commit wires up the xskmap to XDP_DRV layer.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Björn Töpel
fbfc504a24 bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP
The xskmap is yet another BPF map, very much inspired by
dev/cpu/sockmap, and is a holder of AF_XDP sockets. A user application
adds AF_XDP sockets into the map, and by using the bpf_redirect_map
helper, an XDP program can redirect XDP frames to an AF_XDP socket.

Note that a socket that is bound to certain ifindex/queue index will
*only* accept XDP frames from that netdev/queue index. If an XDP
program tries to redirect from a netdev/queue index other than what
the socket is bound to, the frame will not be received on the socket.

A socket can reside in multiple maps.

v3: Fixed race and simplified code.
v2: Removed one indirection in map lookup.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Björn Töpel
c497176cb2 xsk: add Rx receive functions and poll support
Here the actual receive functions of AF_XDP are implemented, that in a
later commit, will be called from the XDP layers.

There's one set of functions for the XDP_DRV side and another for
XDP_SKB (generic).

A new XDP API, xdp_return_buff, is also introduced.

Adding xdp_return_buff, which is analogous to xdp_return_frame, but
acts upon an struct xdp_buff. The API will be used by AF_XDP in future
commits.

Support for the poll syscall is also implemented.

v2: xskq_validate_id did not update cons_tail.
    The entries variable was calculated twice in xskq_nb_avail.
    Squashed xdp_return_buff commit.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Magnus Karlsson
965a990984 xsk: add support for bind for Rx
Here, the bind syscall is added. Binding an AF_XDP socket, means
associating the socket to an umem, a netdev and a queue index. This
can be done in two ways.

The first way, creating a "socket from scratch". Create the umem using
the XDP_UMEM_REG setsockopt and an associated fill queue with
XDP_UMEM_FILL_QUEUE. Create the Rx queue using the XDP_RX_QUEUE
setsockopt. Call bind passing ifindex and queue index ("channel" in
ethtool speak).

The second way to bind a socket, is simply skipping the
umem/netdev/queue index, and passing another already setup AF_XDP
socket. The new socket will then have the same umem/netdev/queue index
as the parent so it will share the same umem. You must also set the
flags field in the socket address to XDP_SHARED_UMEM.

v2: Use PTR_ERR instead of passing error variable explicitly.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:23 -07:00
Björn Töpel
b9b6b68e8a xsk: add Rx queue setup and mmap support
Another setsockopt (XDP_RX_QUEUE) is added to let the process allocate
a queue, where the kernel can pass completed Rx frames from the kernel
to user process.

The mmapping of the queue is done using the XDP_PGOFF_RX_QUEUE offset.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:23 -07:00
Magnus Karlsson
423f38329d xsk: add umem fill queue support and mmap
Here, we add another setsockopt for registered user memory (umem)
called XDP_UMEM_FILL_QUEUE. Using this socket option, the process can
ask the kernel to allocate a queue (ring buffer) and also mmap it
(XDP_UMEM_PGOFF_FILL_QUEUE) into the process.

The queue is used to explicitly pass ownership of umem frames from the
user process to the kernel. These frames will in a later patch be
filled in with Rx packet data by the kernel.

v2: Fixed potential crash in xsk_mmap.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:23 -07:00
Björn Töpel
c0c77d8fb7 xsk: add user memory registration support sockopt
In this commit the base structure of the AF_XDP address family is set
up. Further, we introduce the abilty register a window of user memory
to the kernel via the XDP_UMEM_REG setsockopt syscall. The memory
window is viewed by an AF_XDP socket as a set of equally large
frames. After a user memory registration all frames are "owned" by the
user application, and not the kernel.

v2: More robust checks on umem creation and unaccount on error.
    Call set_page_dirty_lock on cleanup.
    Simplified xdp_umem_reg.

Co-authored-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:23 -07:00
Björn Töpel
68e8b849b2 net: initial AF_XDP skeleton
Buildable skeleton of AF_XDP without any functionality. Just what it
takes to register a new address family.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:23 -07:00
Eric Dumazet
a8d7aa17bb dccp: fix tasklet usage
syzbot reported a crash in tasklet_action_common() caused by dccp.

dccp needs to make sure socket wont disappear before tasklet handler
has completed.

This patch takes a reference on the socket when arming the tasklet,
and moves the sock_put() from dccp_write_xmit_timer() to dccp_write_xmitlet()

kernel BUG at kernel/softirq.c:514!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.17.0-rc3+ #30
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tasklet_action_common.isra.19+0x6db/0x700 kernel/softirq.c:515
RSP: 0018:ffff8801d9b3faf8 EFLAGS: 00010246
dccp_close: ABORT with 65423 bytes unread
RAX: 1ffff1003b367f6b RBX: ffff8801daf1f3f0 RCX: 0000000000000000
RDX: ffff8801cf895498 RSI: 0000000000000004 RDI: 0000000000000000
RBP: ffff8801d9b3fc40 R08: ffffed0039f12a95 R09: ffffed0039f12a94
dccp_close: ABORT with 65423 bytes unread
R10: ffffed0039f12a94 R11: ffff8801cf8954a3 R12: 0000000000000000
R13: ffff8801d9b3fc18 R14: dffffc0000000000 R15: ffff8801cf895490
FS:  0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2bc28000 CR3: 00000001a08a9000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tasklet_action+0x1d/0x20 kernel/softirq.c:533
 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
dccp_close: ABORT with 65423 bytes unread
 run_ksoftirqd+0x86/0x100 kernel/softirq.c:646
 smpboot_thread_fn+0x417/0x870 kernel/smpboot.c:164
 kthread+0x345/0x410 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Code: 48 8b 85 e8 fe ff ff 48 8b 95 f0 fe ff ff e9 94 fb ff ff 48 89 95 f0 fe ff ff e8 81 53 6e 00 48 8b 95 f0 fe ff ff e9 62 fb ff ff <0f> 0b 48 89 cf 48 89 8d e8 fe ff ff e8 64 53 6e 00 48 8b 8d e8
RIP: tasklet_action_common.isra.19+0x6db/0x700 kernel/softirq.c:515 RSP: ffff8801d9b3faf8

Fixes: dc841e30ea ("dccp: Extend CCID packet dequeueing interface")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Cc: dccp@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 15:14:57 -04:00
David S. Miller
31140b47fe Merge branch 'smc-fixes'
Ursula Braun says:

====================
net/smc: fixes 2018/05/03

here are smc fixes for 2 problems:
 * receive buffers in SMC must be registered. If registration fails
   these buffers must not be kept within the link group for reuse.
   Patch 1 is a preparational patch; patch 2 contains the fix.
 * sendpage: do not hold the sock lock when calling kernel_sendpage()
             or sock_no_sendpage()
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 14:47:32 -04:00
Stefan Raspl
bda27ff5c4 smc: fix sendpage() call
The sendpage() call grabs the sock lock before calling the default
implementation - which tries to grab it once again.

Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com><
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 14:47:31 -04:00
Karsten Graul
a6920d1d13 net/smc: handle unregistered buffers
When smc_wr_reg_send() fails then tag (regerr) the affected buffer and
free it in smc_buf_unuse().

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 14:47:31 -04:00
Karsten Graul
e63a5f8c19 net/smc: call consolidation
Consolidate the call to smc_wr_reg_send() in a new function.
No functional changes.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 14:47:31 -04:00
Colin Ian King
df80b8fb3c qed: fix spelling mistake: "offloded" -> "offloaded"
Trivial fix to spelling mistake in DP_NOTICE message

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 14:45:51 -04:00
David S. Miller
62264f99fb Merge branch 'bridge-FDB-Notify-about-removal-of-non-user-added-entries'
Petr Machata says:

====================
bridge: FDB: Notify about removal of non-user-added entries

Device drivers may generally need to keep in sync with bridge's FDB. In
particular, for its offload of tc mirror action where the mirrored-to
device is a gretap device, mlxsw needs to listen to a number of events,
FDB events among the others. SWITCHDEV_FDB_{ADD,DEL}_TO_DEVICE would be
a natural notification in that case.

However, for removal of FDB entries added due to device activity (as
opposed to explicit addition through "bridge fdb add" or similar), there
are no notifications.

Thus in patch #1, add the "added_by_user" field to switchdev
notifications sent for FDB activity. Adapt drivers to ignore activity on
non-user-added entries, to maintain the current behavior. Specifically
in case of mlxsw, allow mlxsw_sp_span_respin() call for any and all FDB
updates.

In patch #2, change the bridge driver to actually emit notifications for
these FDB entries. Take care not to send notification for bridge
updates that itself originate in SWITCHDEV_FDB_*_TO_BRIDGE events.

Changes from v1 to v2:
- Instead of introducing a new variant of fdb_delete(), add a new
  parameter to the existing function.
- Name the parameter swdev_notify, not notify.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:46:48 -04:00
Petr Machata
161d82de1f net: bridge: Notify about !added_by_user FDB entries
Do not automatically bail out on sending notifications about activity on
non-user-added FDB entries. Instead, notify about this activity except
for cases where the activity itself originates in a notification, to
avoid sending duplicate notifications.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:46:47 -04:00
Petr Machata
816a3bed95 switchdev: Add fdb.added_by_user to switchdev notifications
The following patch enables sending notifications also for events on FDB
entries that weren't added by the user. Give the drivers the information
necessary to distinguish between the two origins of FDB entries.

To maintain the current behavior, have switchdev-implementing drivers
bail out on notifications about non-user-added FDB entries. In case of
mlxsw driver, allow a call to mlxsw_sp_span_respin() so that SPAN over
bridge catches up with the changed FDB.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:46:47 -04:00
David S. Miller
0e913f28ba Merge branch 'mlxsw-Introduce-support-for-CQEv1-2'
Ido Schimmel says:

====================
mlxsw: Introduce support for CQEv1/2

Jiri says:

Current SwitchX2 and Spectrum FWs support CQEv0 and that is what we
implement in mlxsw. Spectrum FW also supports CQE v1 and v2.
However, Spectrum-2 won't support CQEv0. Prepare for it and setup the
CQE versions to use according to what is queried from FW.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:44:43 -04:00
Jiri Pirko
41107685b9 mlxsw: pci: Check number of CQEs for CQE version 2
Check number of CQEs for CQE version 2 reported by QUERY_AQ_CAP command.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:44:43 -04:00
Jiri Pirko
8404f6f2e8 mlxsw: pci: Allow to use CQEs of version 1 and version 2
Use previously added resources to query FW support for multiple versions
of CQEs. Use the biggest version supported. For SDQs, it has no sense to
use version 2 as it does not introduce any new features, but it is
twice the size of CQE version 1.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:44:43 -04:00
Jiri Pirko
b76550bbed mlxsw: pci: Introduce helpers to work with multiple CQE versions
Introduce definitions of fields in CQE version 1 and 2. Also, introduce
common helpers that would call appropriate version-specific helpers
according to the version enum passed.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:44:42 -04:00
Jiri Pirko
9b934a3bdc mlxsw: resources: Add CQE versions resources
Add resources that FW uses to report supported CQE versions.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:44:42 -04:00
Nikolay Aleksandrov
faa1cd8298 net: bridge: avoid duplicate notification on up/down/change netdev events
While handling netdevice events, br_device_event() sometimes uses
br_stp_(disable|enable)_port which unconditionally send a notification,
but then a second notification for the same event is sent at the end of
the br_device_event() function. To avoid sending duplicate notifications
in such cases, check if one has already been sent (i.e.
br_stp_enable/disable_port have been called).
The patch is based on a change by Satish Ashok.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:40:54 -04:00
David S. Miller
2e51855194 Merge branch 'selftests-forwarding-sysctl'
Petr Machata says:

====================
selftests: forwarding: Updates to sysctl handling

Some selftests need to adjust sysctl settings. In order to be neutral to
the system that the test is run on, it is a good practice to change back
to the original setting after the test ends. That involves some
boilerplate that can be abstracted away.

In patch #1, introduce two functions, sysctl_set() and sysctl_restore().
The former stores the current value of a given setting, and sets a new
value. The latter restores the setting to the previously-stored value.

In patch #2, use these wrappers in a number of tests.

Additionally in patch #3, fix a problem in mirror_gre_nh.sh, which
neglected to set a sysctl that's crucial for the test to work.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:37:03 -04:00
Petr Machata
7eaaf0bc52 selftests: forwarding: mirror_gre_nh: Unset RP filter
The test fails to work if reverse-path filtering is in effect on the
mirrored-to host interface, or for all interfaces.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:37:02 -04:00
Petr Machata
d51d10aa1d selftests: forwarding: Use sysctl_set(), sysctl_restore()
Instead of hand-managing the sysctl set and restore, use the wrappers
sysctl_set() and sysctl_restore() to do the bookkeeping automatically.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:37:02 -04:00
Petr Machata
f5ae57784b selftests: forwarding: lib: Add sysctl_set(), sysctl_restore()
Add two helper functions: sysctl_set() to change the value of a given
sysctl setting, and sysctl_restore() to change it back to what it was.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-03 13:37:02 -04:00