linux-toradex.git/arch/powerpc/net, branch v4.8

powerpc/ebpf/jit: Implement JIT compiler for extended BPF

2016-06-24T05:17:57+00:00

PPC64 eBPF JIT compiler.

Enable with:
  echo 1 > /proc/sys/net/core/bpf_jit_enable
or
  echo 2 > /proc/sys/net/core/bpf_jit_enable

... to see the generated JIT code. This can further be processed with
tools/net/bpf_jit_disasm.

With CONFIG_TEST_BPF=m and 'modprobe test_bpf':

 test_bpf: Summary: 305 PASSED, 0 FAILED, [297/297 JIT'ed]

... on both ppc64 BE and LE.

The details of the approach are documented through various comments in
the code.

Acked-by: Alexei Starovoitov 
Signed-off-by: Naveen N. Rao 
Signed-off-by: Michael Ellerman

powerpc/bpf/jit: Isolate classic BPF JIT specifics into a separate header

2016-06-24T05:15:51+00:00

Break out classic BPF JIT specifics into a separate header in
preparation for eBPF JIT implementation. Note that ppc32 will still need
the classic BPF JIT.

Acked-by: Alexei Starovoitov 
Signed-off-by: Naveen N. Rao 
Signed-off-by: Michael Ellerman

powerpc/bpf/jit: A few cleanups

2016-06-24T05:15:37+00:00

1. Per the ISA, ADDIS actually uses RT, rather than RS. Though
   the result is the same, make the usage clear.
2. The multiply instruction used is a 32-bit multiply. Rename PPC_MUL()
   to PPC_MULW() to make the same clear.
3. PPC_STW[U] take the entire 16-bit immediate value and do not require
   word-alignment, per the ISA. Change the macros to use IMM_L().
4. A few white-space cleanups to satisfy checkpatch.pl.

Acked-by: Alexei Starovoitov 
Signed-off-by: Naveen N. Rao 
Signed-off-by: Michael Ellerman

powerpc/bpf/jit: Introduce rotate immediate instructions

2016-06-24T05:15:14+00:00

Since we will be using the rotate immediate instructions for extended
BPF JIT, let's introduce macros for the same. And since the shift
immediate operations use the rotate immediate instructions, let's redo
those macros to use the newly introduced instructions.

Acked-by: Alexei Starovoitov 
Signed-off-by: Naveen N. Rao 
Signed-off-by: Michael Ellerman

powerpc/bpf/jit: Optimize 64-bit Immediate loads

2016-06-24T05:15:04+00:00

Similar to the LI32() optimization, if the value can be represented
in 32-bits, use LI32(). Also handle loading a few specific forms of
immediate values in an optimum manner.

Acked-by: Alexei Starovoitov 
Signed-off-by: Naveen N. Rao 
Signed-off-by: Michael Ellerman

powerpc/bpf/jit: Fix/enhance 32-bit Load Immediate implementation

2016-06-24T05:14:45+00:00

The existing LI32() macro can sometimes result in a sign-extended 32-bit
load that does not clear the top 32-bits properly. As an example,
loading 0x7fffffff results in the register containing
0xffffffff7fffffff. While this does not impact classic BPF JIT
implementation (since that only uses the lower word for all operations),
we would like to share this macro between classic BPF JIT and extended
BPF JIT, wherein the entire 64-bit value in the register matters. Fix
this by first doing a shifted LI followed by ORI.

An additional optimization is with loading values between -32768 to -1,
where we now only need a single LI.

The new implementation now generates the same or less number of
instructions.

Acked-by: Alexei Starovoitov 
Signed-off-by: Naveen N. Rao 
Signed-off-by: Michael Ellerman

net: filter: make JITs zero A for SKF_AD_ALU_XOR_X

2016-01-06T05:43:52+00:00

The SKF_AD_ALU_XOR_X ancillary is not like the other ancillary data
instructions since it XORs A with X while all the others replace A with
some loaded value.  All the BPF JITs fail to clear A if this is used as
the first instruction in a filter.  This was found using american fuzzy
lop.

Add a helper to determine if A needs to be cleared given the first
instruction in a filter, and use this in the JITs.  Except for ARM, the
rest have only been compile-tested.

Fixes: 3480593131e0 ("net: filter: get rid of BPF_S_* enum")
Signed-off-by: Rabin Vincent 
Acked-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

ebpf: migrate bpf_prog's flags to bitfield

2015-10-03T12:02:39+00:00

As we need to add further flags to the bpf_prog structure, lets migrate
both bools to a bitfield representation. The size of the base structure
(excluding insns) remains unchanged at 40 bytes.

Add also tags for the kmemchecker, so that it doesn't throw false
positives. Even in case gcc would generate suboptimal code, it's not
being accessed in performance critical paths.

Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

ppc: bpf: Add SKF_AD_CPU for ppc32

2015-02-20T20:19:43+00:00

Signed-off-by: Denis Kirjanov 
Signed-off-by: David S. Miller

ppc: bpf: rename bpf_jit_64.S to bpf_jit_asm.S

2015-02-20T20:19:43+00:00

Signed-off-by: Denis Kirjanov 
Signed-off-by: David S. Miller