diff options
| author | Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> | 2016-09-24 02:05:00 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2016-10-04 20:33:19 +1100 |
| commit | 7b847f523fe07b4ad73a01cec49a4da86a9be412 (patch) | |
| tree | 054b86d2a84abc70d93b77b2a672cb189e67b613 /arch/powerpc/net/bpf_jit64.h | |
| parent | 2685f826e5ffd1ab73b26fd5ac4e1f7048cb6ff6 (diff) | |
powerpc/bpf: Introduce accessors for using the tmp local stack space
While at it, ensure that the location of the local save area is
consistent whether or not we setup our own stackframe. This property is
utilised in the next patch that adds support for tail calls.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/net/bpf_jit64.h')
| -rw-r--r-- | arch/powerpc/net/bpf_jit64.h | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/arch/powerpc/net/bpf_jit64.h b/arch/powerpc/net/bpf_jit64.h index 5046d6f65c02..a1645d7a4033 100644 --- a/arch/powerpc/net/bpf_jit64.h +++ b/arch/powerpc/net/bpf_jit64.h @@ -16,22 +16,25 @@ /* * Stack layout: + * Ensure the top half (upto local_tmp_var) stays consistent + * with our redzone usage. * * [ prev sp ] <------------- * [ nv gpr save area ] 8*8 | + * [ tail_call_cnt ] 8 | + * [ local_tmp_var ] 8 | * fp (r31) --> [ ebpf stack space ] 512 | - * [ local/tmp var space ] 16 | * [ frame header ] 32/112 | * sp (r1) ---> [ stack pointer ] -------------- */ -/* for bpf JIT code internal usage */ -#define BPF_PPC_STACK_LOCALS 16 /* for gpr non volatile registers BPG_REG_6 to 10, plus skb cache registers */ #define BPF_PPC_STACK_SAVE (8*8) +/* for bpf JIT code internal usage */ +#define BPF_PPC_STACK_LOCALS 16 /* Ensure this is quadword aligned */ -#define BPF_PPC_STACKFRAME (STACK_FRAME_MIN_SIZE + BPF_PPC_STACK_LOCALS + \ - MAX_BPF_STACK + BPF_PPC_STACK_SAVE) +#define BPF_PPC_STACKFRAME (STACK_FRAME_MIN_SIZE + MAX_BPF_STACK + \ + BPF_PPC_STACK_LOCALS + BPF_PPC_STACK_SAVE) #ifndef __ASSEMBLY__ @@ -65,6 +68,9 @@ static const int b2p[] = { [TMP_REG_2] = 10 }; +/* PPC NVR range -- update this if we ever use NVRs below r24 */ +#define BPF_PPC_NVR_MIN 24 + /* Assembly helpers */ #define DECLARE_LOAD_FUNC(func) u64 func(u64 r3, u64 r4); \ u64 func##_negative_offset(u64 r3, u64 r4); \ |