[tip:x86/debug] x86/asm/bpf: Annotate callable functions

From: tip-bot for Josh Poimboeuf
Date: Thu Feb 25 2016 - 00:52:15 EST


Commit-ID: 2d8fe90a1b96d52c2a3f719c385b846b02f0bcd8
Gitweb: http://git.kernel.org/tip/2d8fe90a1b96d52c2a3f719c385b846b02f0bcd8
Author: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
AuthorDate: Thu, 21 Jan 2016 16:49:26 -0600
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 24 Feb 2016 08:35:43 +0100

x86/asm/bpf: Annotate callable functions

bpf_jit.S has several functions which can be called from C code. Give
them proper ELF annotations.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Bernd Petrovitsch <bernd@xxxxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Brian Gerst <brgerst@xxxxxxxxx>
Cc: Chris J Arges <chris.j.arges@xxxxxxxxxxxxx>
Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Jiri Slaby <jslaby@xxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Michal Marek <mmarek@xxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxx>
Cc: Pedro Alves <palves@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: live-patching@xxxxxxxxxxxxxxx
Cc: netdev@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/bbe1de0c299fecd4fc9a1766bae8be2647bedb01.1453405861.git.jpoimboe@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/net/bpf_jit.S | 39 ++++++++++++++++-----------------------
1 file changed, 16 insertions(+), 23 deletions(-)

diff --git a/arch/x86/net/bpf_jit.S b/arch/x86/net/bpf_jit.S
index 4093216..eb4a3bd 100644
--- a/arch/x86/net/bpf_jit.S
+++ b/arch/x86/net/bpf_jit.S
@@ -22,15 +22,16 @@
32 /* space for rbx,r13,r14,r15 */ + \
8 /* space for skb_copy_bits */)

-sk_load_word:
- .globl sk_load_word
+#define FUNC(name) \
+ .globl name; \
+ .type name, @function; \
+ name:

+FUNC(sk_load_word)
test %esi,%esi
js bpf_slow_path_word_neg

-sk_load_word_positive_offset:
- .globl sk_load_word_positive_offset
-
+FUNC(sk_load_word_positive_offset)
mov %r9d,%eax # hlen
sub %esi,%eax # hlen - offset
cmp $3,%eax
@@ -39,15 +40,11 @@ sk_load_word_positive_offset:
bswap %eax /* ntohl() */
ret

-sk_load_half:
- .globl sk_load_half
-
+FUNC(sk_load_half)
test %esi,%esi
js bpf_slow_path_half_neg

-sk_load_half_positive_offset:
- .globl sk_load_half_positive_offset
-
+FUNC(sk_load_half_positive_offset)
mov %r9d,%eax
sub %esi,%eax # hlen - offset
cmp $1,%eax
@@ -56,15 +53,11 @@ sk_load_half_positive_offset:
rol $8,%ax # ntohs()
ret

-sk_load_byte:
- .globl sk_load_byte
-
+FUNC(sk_load_byte)
test %esi,%esi
js bpf_slow_path_byte_neg

-sk_load_byte_positive_offset:
- .globl sk_load_byte_positive_offset
-
+FUNC(sk_load_byte_positive_offset)
cmp %esi,%r9d /* if (offset >= hlen) goto bpf_slow_path_byte */
jle bpf_slow_path_byte
movzbl (SKBDATA,%rsi),%eax
@@ -120,8 +113,8 @@ bpf_slow_path_byte:
bpf_slow_path_word_neg:
cmp SKF_MAX_NEG_OFF, %esi /* test range */
jl bpf_error /* offset lower -> error */
-sk_load_word_negative_offset:
- .globl sk_load_word_negative_offset
+
+FUNC(sk_load_word_negative_offset)
sk_negative_common(4)
mov (%rax), %eax
bswap %eax
@@ -130,8 +123,8 @@ sk_load_word_negative_offset:
bpf_slow_path_half_neg:
cmp SKF_MAX_NEG_OFF, %esi
jl bpf_error
-sk_load_half_negative_offset:
- .globl sk_load_half_negative_offset
+
+FUNC(sk_load_half_negative_offset)
sk_negative_common(2)
mov (%rax),%ax
rol $8,%ax
@@ -141,8 +134,8 @@ sk_load_half_negative_offset:
bpf_slow_path_byte_neg:
cmp SKF_MAX_NEG_OFF, %esi
jl bpf_error
-sk_load_byte_negative_offset:
- .globl sk_load_byte_negative_offset
+
+FUNC(sk_load_byte_negative_offset)
sk_negative_common(1)
movzbl (%rax), %eax
ret