Introduce a helper to store 64-bit immediate on the trampoline stack with a help of a register. Signed-off-by: Menglong Dong --- arch/riscv/net/bpf_jit_comp64.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index 37888abee70c..e4f45e2e7e2f 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -926,6 +926,14 @@ static void restore_stack_args(int nr_stack_args, int args_off, int stk_arg_off, } } +static void emit_store_stack_imm64(u8 reg, int stack_off, u64 imm64, + struct rv_jit_context *ctx) +{ + /* Load imm64 into reg and store it at [FP + stack_off]. */ + emit_imm(reg, (s64)imm64, ctx); + emit_sd(RV_REG_FP, stack_off, reg, ctx); +} + static int invoke_bpf_prog(struct bpf_tramp_link *l, int args_off, int retval_off, int run_ctx_off, bool save_ret, struct rv_jit_context *ctx) { @@ -933,12 +941,10 @@ static int invoke_bpf_prog(struct bpf_tramp_link *l, int args_off, int retval_of struct bpf_prog *p = l->link.prog; int cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie); - if (l->cookie) { - emit_imm(RV_REG_T1, l->cookie, ctx); - emit_sd(RV_REG_FP, -run_ctx_off + cookie_off, RV_REG_T1, ctx); - } else { + if (l->cookie) + emit_store_stack_imm64(RV_REG_T1, -run_ctx_off + cookie_off, l->cookie, ctx); + else emit_sd(RV_REG_FP, -run_ctx_off + cookie_off, RV_REG_ZERO, ctx); - } /* arg1: prog */ emit_imm(RV_REG_A0, (const s64)p, ctx); @@ -1123,13 +1129,10 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, emit_sd(RV_REG_FP, -sreg_off, RV_REG_S1, ctx); /* store ip address of the traced function */ - if (flags & BPF_TRAMP_F_IP_ARG) { - emit_imm(RV_REG_T1, (const s64)func_addr, ctx); - emit_sd(RV_REG_FP, -ip_off, RV_REG_T1, ctx); - } + if (flags & BPF_TRAMP_F_IP_ARG) + emit_store_stack_imm64(RV_REG_T1, -ip_off, (u64)func_addr, ctx); - emit_li(RV_REG_T1, nr_arg_slots, ctx); - emit_sd(RV_REG_FP, -nregs_off, RV_REG_T1, ctx); + emit_store_stack_imm64(RV_REG_T1, -nregs_off, nr_arg_slots, ctx); store_args(nr_arg_slots, args_off, ctx); -- 2.52.0