diff options
Diffstat (limited to 'arch/powerpc/net/bpf_jit_comp64.c')
| -rw-r--r-- | arch/powerpc/net/bpf_jit_comp64.c | 54 |
1 files changed, 53 insertions, 1 deletions
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c index eeda636cd7be..3e4ed5560947 100644 --- a/arch/powerpc/net/bpf_jit_comp64.c +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -17,7 +17,59 @@ #include <linux/bpf.h> #include <asm/security_features.h> -#include "bpf_jit64.h" +#include "bpf_jit.h" + +/* + * Stack layout: + * Ensure the top half (upto local_tmp_var) stays consistent + * with our redzone usage. + * + * [ prev sp ] <------------- + * [ nv gpr save area ] 5*8 | + * [ tail_call_cnt ] 8 | + * [ local_tmp_var ] 16 | + * fp (r31) --> [ ebpf stack space ] upto 512 | + * [ frame header ] 32/112 | + * sp (r1) ---> [ stack pointer ] -------------- + */ + +/* for gpr non volatile registers BPG_REG_6 to 10 */ +#define BPF_PPC_STACK_SAVE (5*8) +/* for bpf JIT code internal usage */ +#define BPF_PPC_STACK_LOCALS 24 +/* stack frame excluding BPF stack, ensure this is quadword aligned */ +#define BPF_PPC_STACKFRAME (STACK_FRAME_MIN_SIZE + \ + BPF_PPC_STACK_LOCALS + BPF_PPC_STACK_SAVE) + +/* BPF register usage */ +#define TMP_REG_1 (MAX_BPF_JIT_REG + 0) +#define TMP_REG_2 (MAX_BPF_JIT_REG + 1) + +/* BPF to ppc register mappings */ +const int b2p[MAX_BPF_JIT_REG + 2] = { + /* function return value */ + [BPF_REG_0] = 8, + /* function arguments */ + [BPF_REG_1] = 3, + [BPF_REG_2] = 4, + [BPF_REG_3] = 5, + [BPF_REG_4] = 6, + [BPF_REG_5] = 7, + /* non volatile registers */ + [BPF_REG_6] = 27, + [BPF_REG_7] = 28, + [BPF_REG_8] = 29, + [BPF_REG_9] = 30, + /* frame pointer aka BPF_REG_10 */ + [BPF_REG_FP] = 31, + /* eBPF jit internal registers */ + [BPF_REG_AX] = 12, + [TMP_REG_1] = 9, + [TMP_REG_2] = 10 +}; + +/* PPC NVR range -- update this if we ever use NVRs below r27 */ +#define BPF_PPC_NVR_MIN 27 static inline bool bpf_has_stack_frame(struct codegen_context *ctx) { |