This patch is a follow-up for patch "net: filter: add vlan tag access"
to support the new VLAN_TAG/VLAN_TAG_PRESENT accessors in BPF JIT.
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is a follow-up for patch "filter: add XOR instruction for use
with X/K" that implements BPF PowerPC JIT parts for the BPF XOR operation.
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Anything that uses a constructed instruction (ie. from ppc-opcode.h),
need to use the new R0 macro, as %r0 is not going to work.
Also convert usages of macros where we are just determining an offset
(usually for a load/store), like:
std r14,STK_REG(r14)(r1)
Can't use STK_REG(r14) as %r14 doesn't work in the STK_REG macro since
it's just calculating an offset.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now the helper function from filter.c for negative offsets is exported,
it can be used it in the jit to handle negative offsets.
First modify the asm load helper functions to handle:
- know positive offsets
- know negative offsets
- any offset
then the compiler can be modified to explicitly use these helper
when appropriate.
This fixes the case of a negative X register and allows to lift
the restriction that bpf programs with negative offsets can't
be jited.
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jan Seiffert <kaffeemonster@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An implementation of a code generator for BPF programs to speed up packet
filtering on PPC64, inspired by Eric Dumazet's x86-64 version.
Filter code is generated as an ABI-compliant function in module_alloc()'d mem
with stackframe & prologue/epilogue generated if required (simple filters don't
need anything more than an li/blr). The filter's local variables, M[], live in
registers. Supports all BPF opcodes, although "complicated" loads from negative
packet offsets (e.g. SKF_LL_OFF) are not yet supported.
There are a couple of further optimisations left for future work; many-pass
assembly with branch-reach reduction and a register allocator to push M[]
variables into volatile registers would improve the code quality further.
This currently supports big-endian 64-bit PowerPC only (but is fairly simple
to port to PPC32 or LE!).
Enabled in the same way as x86-64:
echo 1 > /proc/sys/net/core/bpf_jit_enable
Or, enabled with extra debug output:
echo 2 > /proc/sys/net/core/bpf_jit_enable
Signed-off-by: Matt Evans <matt@ozlabs.org>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
