[PATCH RFC bpf-next 6/7] bpf,x86: implement bpf_arch_text_poke_type for x86_64

[Menglong Dong]

Implement the bpf_arch_text_poke_type() for x86_64.

Signed-off-by: Menglong Dong <dong...@chinatelecom.cn>
---
 arch/x86/net/bpf_jit_comp.c | 28 +++++++++++++++++++++-------
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 21ce2b8457ec..c82bd282988f 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -597,8 +597,9 @@ static int emit_jump(u8 **pprog, void *func, void *ip)
        return emit_patch(pprog, func, ip, 0xE9);
 }
 
-static int __bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
-                               void *old_addr, void *new_addr)
+static int ___bpf_arch_text_poke(void *ip, enum bpf_text_poke_type old_t,
+                                enum bpf_text_poke_type new_t,
+                                void *old_addr, void *new_addr)
 {
        const u8 *nop_insn = x86_nops[5];
        u8 old_insn[X86_PATCH_SIZE];
@@ -609,7 +610,7 @@ static int __bpf_arch_text_poke(void *ip, enum 
bpf_text_poke_type t,
        memcpy(old_insn, nop_insn, X86_PATCH_SIZE);
        if (old_addr) {
                prog = old_insn;
-               ret = t == BPF_MOD_CALL ?
+               ret = old_t == BPF_MOD_CALL ?
                      emit_call(&prog, old_addr, ip) :
                      emit_jump(&prog, old_addr, ip);
                if (ret)
@@ -619,7 +620,7 @@ static int __bpf_arch_text_poke(void *ip, enum 
bpf_text_poke_type t,
        memcpy(new_insn, nop_insn, X86_PATCH_SIZE);
        if (new_addr) {
                prog = new_insn;
-               ret = t == BPF_MOD_CALL ?
+               ret = new_t == BPF_MOD_CALL ?
                      emit_call(&prog, new_addr, ip) :
                      emit_jump(&prog, new_addr, ip);
                if (ret)
@@ -640,8 +641,15 @@ static int __bpf_arch_text_poke(void *ip, enum 
bpf_text_poke_type t,
        return ret;
 }
 
-int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
-                      void *old_addr, void *new_addr)
+static int __bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
+                                void *old_addr, void *new_addr)
+{
+       return ___bpf_arch_text_poke(ip, t, t, old_addr, new_addr);
+}
+
+int bpf_arch_text_poke_type(void *ip, enum bpf_text_poke_type old_t,
+                           enum bpf_text_poke_type new_t, void *old_addr,
+                           void *new_addr)
 {
        if (!is_kernel_text((long)ip) &&
            !is_bpf_text_address((long)ip))
@@ -655,7 +663,13 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
        if (is_endbr(ip))
                ip += ENDBR_INSN_SIZE;
 
-       return __bpf_arch_text_poke(ip, t, old_addr, new_addr);
+       return ___bpf_arch_text_poke(ip, old_t, new_t, old_addr, new_addr);
+}
+
+int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
+                      void *old_addr, void *new_addr)
+{
+       return bpf_arch_text_poke_type(ip, t, t, old_addr, new_addr);
 }
 
 #define EMIT_LFENCE()  EMIT3(0x0F, 0xAE, 0xE8)
-- 
2.51.2