From 88fd9e5352fe05f7fe57778293aebd4cd106960b Mon Sep 17 00:00:00 2001 From: KP Singh Date: Wed, 4 Mar 2020 20:18:47 +0100 Subject: bpf: Refactor trampoline update code As we need to introduce a third type of attachment for trampolines, the flattened signature of arch_prepare_bpf_trampoline gets even more complicated. Refactor the prog and count argument to arch_prepare_bpf_trampoline to use bpf_tramp_progs to simplify the addition and accounting for new attachment types. Signed-off-by: KP Singh Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200304191853.1529-2-kpsingh@chromium.org --- arch/x86/net/bpf_jit_comp.c | 31 ++++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) (limited to 'arch/x86/net') diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 9ba08e9abc09..15c7d28bc05c 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1362,12 +1362,12 @@ static void restore_regs(const struct btf_func_model *m, u8 **prog, int nr_args, } static int invoke_bpf(const struct btf_func_model *m, u8 **pprog, - struct bpf_prog **progs, int prog_cnt, int stack_size) + struct bpf_tramp_progs *tp, int stack_size) { u8 *prog = *pprog; int cnt = 0, i; - for (i = 0; i < prog_cnt; i++) { + for (i = 0; i < tp->nr_progs; i++) { if (emit_call(&prog, __bpf_prog_enter, prog)) return -EINVAL; /* remember prog start time returned by __bpf_prog_enter */ @@ -1376,17 +1376,17 @@ static int invoke_bpf(const struct btf_func_model *m, u8 **pprog, /* arg1: lea rdi, [rbp - stack_size] */ EMIT4(0x48, 0x8D, 0x7D, -stack_size); /* arg2: progs[i]->insnsi for interpreter */ - if (!progs[i]->jited) + if (!tp->progs[i]->jited) emit_mov_imm64(&prog, BPF_REG_2, - (long) progs[i]->insnsi >> 32, - (u32) (long) progs[i]->insnsi); + (long) tp->progs[i]->insnsi >> 32, + (u32) (long) tp->progs[i]->insnsi); /* call JITed bpf program or interpreter */ - if (emit_call(&prog, progs[i]->bpf_func, prog)) + if (emit_call(&prog, tp->progs[i]->bpf_func, prog)) return -EINVAL; /* arg1: mov rdi, progs[i] */ - emit_mov_imm64(&prog, BPF_REG_1, (long) progs[i] >> 32, - (u32) (long) progs[i]); + emit_mov_imm64(&prog, BPF_REG_1, (long) tp->progs[i] >> 32, + (u32) (long) tp->progs[i]); /* arg2: mov rsi, rbx <- start time in nsec */ emit_mov_reg(&prog, true, BPF_REG_2, BPF_REG_6); if (emit_call(&prog, __bpf_prog_exit, prog)) @@ -1458,12 +1458,13 @@ static int invoke_bpf(const struct btf_func_model *m, u8 **pprog, */ int arch_prepare_bpf_trampoline(void *image, void *image_end, const struct btf_func_model *m, u32 flags, - struct bpf_prog **fentry_progs, int fentry_cnt, - struct bpf_prog **fexit_progs, int fexit_cnt, + struct bpf_tramp_progs *tprogs, void *orig_call) { int cnt = 0, nr_args = m->nr_args; int stack_size = nr_args * 8; + struct bpf_tramp_progs *fentry = &tprogs[BPF_TRAMP_FENTRY]; + struct bpf_tramp_progs *fexit = &tprogs[BPF_TRAMP_FEXIT]; u8 *prog; /* x86-64 supports up to 6 arguments. 7+ can be added in the future */ @@ -1492,12 +1493,12 @@ int arch_prepare_bpf_trampoline(void *image, void *image_end, save_regs(m, &prog, nr_args, stack_size); - if (fentry_cnt) - if (invoke_bpf(m, &prog, fentry_progs, fentry_cnt, stack_size)) + if (fentry->nr_progs) + if (invoke_bpf(m, &prog, fentry, stack_size)) return -EINVAL; if (flags & BPF_TRAMP_F_CALL_ORIG) { - if (fentry_cnt) + if (fentry->nr_progs) restore_regs(m, &prog, nr_args, stack_size); /* call original function */ @@ -1507,8 +1508,8 @@ int arch_prepare_bpf_trampoline(void *image, void *image_end, emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8); } - if (fexit_cnt) - if (invoke_bpf(m, &prog, fexit_progs, fexit_cnt, stack_size)) + if (fexit->nr_progs) + if (invoke_bpf(m, &prog, fexit, stack_size)) return -EINVAL; if (flags & BPF_TRAMP_F_RESTORE_REGS) -- cgit v1.2.3