diff mbox

[net-next,v2,1/5] net: filter: simplify label names from jump-table

Message ID 1398321927-8845-2-git-send-email-dborkman@redhat.com
State Changes Requested, archived
Delegated to: David Miller
Headers show

Commit Message

Daniel Borkmann April 24, 2014, 6:45 a.m. UTC 
This patch simplifies label naming for the BPF jump-table.
When we define labels via DL(), we just concatenate/textify
the combination of instruction opcode which consists of the
class, subclass, word size, target register and so on. Each
time we leave BPF_ prefix intact, so that e.g. the preprocessor
generates a label BPF_ALU_BPF_ADD_BPF_X for DL(BPF_ALU, BPF_ADD,
BPF_X) whereas a label name of ALU_ADD_X is much more easy
to grasp.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
---
 include/linux/filter.h |   3 +
 net/core/filter.c      | 308 ++++++++++++++++++++++++-------------------------
 2 files changed, 157 insertions(+), 154 deletions(-)
diff mbox

Patch

diff --git a/include/linux/filter.h b/include/linux/filter.h
index 759abf7..b042d1d 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -37,6 +37,9 @@ 
 #define BPF_CALL	0x80	/* function call */
 #define BPF_EXIT	0x90	/* function return */
 
+/* Placeholder/dummy for 0 */
+#define BPF_0		0
+
 /* BPF has 10 general purpose 64-bit registers and stack frame. */
 #define MAX_BPF_REG	11
 
diff --git a/net/core/filter.c b/net/core/filter.c
index 7c4db3d..a1784e9 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -156,94 +156,94 @@  unsigned int __sk_run_filter(void *ctx, const struct sock_filter_int *insn)
 	static const void *jumptable[256] = {
 		[0 ... 255] = &&default_label,
 		/* Now overwrite non-defaults ... */
-#define DL(A, B, C)	[A|B|C] = &&A##_##B##_##C
-		DL(BPF_ALU, BPF_ADD, BPF_X),
-		DL(BPF_ALU, BPF_ADD, BPF_K),
-		DL(BPF_ALU, BPF_SUB, BPF_X),
-		DL(BPF_ALU, BPF_SUB, BPF_K),
-		DL(BPF_ALU, BPF_AND, BPF_X),
-		DL(BPF_ALU, BPF_AND, BPF_K),
-		DL(BPF_ALU, BPF_OR, BPF_X),
-		DL(BPF_ALU, BPF_OR, BPF_K),
-		DL(BPF_ALU, BPF_LSH, BPF_X),
-		DL(BPF_ALU, BPF_LSH, BPF_K),
-		DL(BPF_ALU, BPF_RSH, BPF_X),
-		DL(BPF_ALU, BPF_RSH, BPF_K),
-		DL(BPF_ALU, BPF_XOR, BPF_X),
-		DL(BPF_ALU, BPF_XOR, BPF_K),
-		DL(BPF_ALU, BPF_MUL, BPF_X),
-		DL(BPF_ALU, BPF_MUL, BPF_K),
-		DL(BPF_ALU, BPF_MOV, BPF_X),
-		DL(BPF_ALU, BPF_MOV, BPF_K),
-		DL(BPF_ALU, BPF_DIV, BPF_X),
-		DL(BPF_ALU, BPF_DIV, BPF_K),
-		DL(BPF_ALU, BPF_MOD, BPF_X),
-		DL(BPF_ALU, BPF_MOD, BPF_K),
-		DL(BPF_ALU, BPF_NEG, 0),
-		DL(BPF_ALU, BPF_END, BPF_TO_BE),
-		DL(BPF_ALU, BPF_END, BPF_TO_LE),
-		DL(BPF_ALU64, BPF_ADD, BPF_X),
-		DL(BPF_ALU64, BPF_ADD, BPF_K),
-		DL(BPF_ALU64, BPF_SUB, BPF_X),
-		DL(BPF_ALU64, BPF_SUB, BPF_K),
-		DL(BPF_ALU64, BPF_AND, BPF_X),
-		DL(BPF_ALU64, BPF_AND, BPF_K),
-		DL(BPF_ALU64, BPF_OR, BPF_X),
-		DL(BPF_ALU64, BPF_OR, BPF_K),
-		DL(BPF_ALU64, BPF_LSH, BPF_X),
-		DL(BPF_ALU64, BPF_LSH, BPF_K),
-		DL(BPF_ALU64, BPF_RSH, BPF_X),
-		DL(BPF_ALU64, BPF_RSH, BPF_K),
-		DL(BPF_ALU64, BPF_XOR, BPF_X),
-		DL(BPF_ALU64, BPF_XOR, BPF_K),
-		DL(BPF_ALU64, BPF_MUL, BPF_X),
-		DL(BPF_ALU64, BPF_MUL, BPF_K),
-		DL(BPF_ALU64, BPF_MOV, BPF_X),
-		DL(BPF_ALU64, BPF_MOV, BPF_K),
-		DL(BPF_ALU64, BPF_ARSH, BPF_X),
-		DL(BPF_ALU64, BPF_ARSH, BPF_K),
-		DL(BPF_ALU64, BPF_DIV, BPF_X),
-		DL(BPF_ALU64, BPF_DIV, BPF_K),
-		DL(BPF_ALU64, BPF_MOD, BPF_X),
-		DL(BPF_ALU64, BPF_MOD, BPF_K),
-		DL(BPF_ALU64, BPF_NEG, 0),
-		DL(BPF_JMP, BPF_CALL, 0),
-		DL(BPF_JMP, BPF_JA, 0),
-		DL(BPF_JMP, BPF_JEQ, BPF_X),
-		DL(BPF_JMP, BPF_JEQ, BPF_K),
-		DL(BPF_JMP, BPF_JNE, BPF_X),
-		DL(BPF_JMP, BPF_JNE, BPF_K),
-		DL(BPF_JMP, BPF_JGT, BPF_X),
-		DL(BPF_JMP, BPF_JGT, BPF_K),
-		DL(BPF_JMP, BPF_JGE, BPF_X),
-		DL(BPF_JMP, BPF_JGE, BPF_K),
-		DL(BPF_JMP, BPF_JSGT, BPF_X),
-		DL(BPF_JMP, BPF_JSGT, BPF_K),
-		DL(BPF_JMP, BPF_JSGE, BPF_X),
-		DL(BPF_JMP, BPF_JSGE, BPF_K),
-		DL(BPF_JMP, BPF_JSET, BPF_X),
-		DL(BPF_JMP, BPF_JSET, BPF_K),
-		DL(BPF_JMP, BPF_EXIT, 0),
-		DL(BPF_STX, BPF_MEM, BPF_B),
-		DL(BPF_STX, BPF_MEM, BPF_H),
-		DL(BPF_STX, BPF_MEM, BPF_W),
-		DL(BPF_STX, BPF_MEM, BPF_DW),
-		DL(BPF_STX, BPF_XADD, BPF_W),
-		DL(BPF_STX, BPF_XADD, BPF_DW),
-		DL(BPF_ST, BPF_MEM, BPF_B),
-		DL(BPF_ST, BPF_MEM, BPF_H),
-		DL(BPF_ST, BPF_MEM, BPF_W),
-		DL(BPF_ST, BPF_MEM, BPF_DW),
-		DL(BPF_LDX, BPF_MEM, BPF_B),
-		DL(BPF_LDX, BPF_MEM, BPF_H),
-		DL(BPF_LDX, BPF_MEM, BPF_W),
-		DL(BPF_LDX, BPF_MEM, BPF_DW),
-		DL(BPF_LD, BPF_ABS, BPF_W),
-		DL(BPF_LD, BPF_ABS, BPF_H),
-		DL(BPF_LD, BPF_ABS, BPF_B),
-		DL(BPF_LD, BPF_IND, BPF_W),
-		DL(BPF_LD, BPF_IND, BPF_H),
-		DL(BPF_LD, BPF_IND, BPF_B),
+#define DL(A, B, C)	[BPF_##A|BPF_##B|BPF_##C] = &&A##_##B##_##C
+		DL(ALU, ADD, X),
+		DL(ALU, ADD, K),
+		DL(ALU, SUB, X),
+		DL(ALU, SUB, K),
+		DL(ALU, AND, X),
+		DL(ALU, AND, K),
+		DL(ALU, OR, X),
+		DL(ALU, OR, K),
+		DL(ALU, LSH, X),
+		DL(ALU, LSH, K),
+		DL(ALU, RSH, X),
+		DL(ALU, RSH, K),
+		DL(ALU, XOR, X),
+		DL(ALU, XOR, K),
+		DL(ALU, MUL, X),
+		DL(ALU, MUL, K),
+		DL(ALU, MOV, X),
+		DL(ALU, MOV, K),
+		DL(ALU, DIV, X),
+		DL(ALU, DIV, K),
+		DL(ALU, MOD, X),
+		DL(ALU, MOD, K),
+		DL(ALU, NEG, 0),
+		DL(ALU, END, TO_BE),
+		DL(ALU, END, TO_LE),
+		DL(ALU64, ADD, X),
+		DL(ALU64, ADD, K),
+		DL(ALU64, SUB, X),
+		DL(ALU64, SUB, K),
+		DL(ALU64, AND, X),
+		DL(ALU64, AND, K),
+		DL(ALU64, OR, X),
+		DL(ALU64, OR, K),
+		DL(ALU64, LSH, X),
+		DL(ALU64, LSH, K),
+		DL(ALU64, RSH, X),
+		DL(ALU64, RSH, K),
+		DL(ALU64, XOR, X),
+		DL(ALU64, XOR, K),
+		DL(ALU64, MUL, X),
+		DL(ALU64, MUL, K),
+		DL(ALU64, MOV, X),
+		DL(ALU64, MOV, K),
+		DL(ALU64, ARSH, X),
+		DL(ALU64, ARSH, K),
+		DL(ALU64, DIV, X),
+		DL(ALU64, DIV, K),
+		DL(ALU64, MOD, X),
+		DL(ALU64, MOD, K),
+		DL(ALU64, NEG, 0),
+		DL(JMP, CALL, 0),
+		DL(JMP, JA, 0),
+		DL(JMP, JEQ, X),
+		DL(JMP, JEQ, K),
+		DL(JMP, JNE, X),
+		DL(JMP, JNE, K),
+		DL(JMP, JGT, X),
+		DL(JMP, JGT, K),
+		DL(JMP, JGE, X),
+		DL(JMP, JGE, K),
+		DL(JMP, JSGT, X),
+		DL(JMP, JSGT, K),
+		DL(JMP, JSGE, X),
+		DL(JMP, JSGE, K),
+		DL(JMP, JSET, X),
+		DL(JMP, JSET, K),
+		DL(JMP, EXIT, 0),
+		DL(STX, MEM, B),
+		DL(STX, MEM, H),
+		DL(STX, MEM, W),
+		DL(STX, MEM, DW),
+		DL(STX, XADD, W),
+		DL(STX, XADD, DW),
+		DL(ST, MEM, B),
+		DL(ST, MEM, H),
+		DL(ST, MEM, W),
+		DL(ST, MEM, DW),
+		DL(LDX, MEM, B),
+		DL(LDX, MEM, H),
+		DL(LDX, MEM, W),
+		DL(LDX, MEM, DW),
+		DL(LD, ABS, W),
+		DL(LD, ABS, H),
+		DL(LD, ABS, B),
+		DL(LD, IND, W),
+		DL(LD, IND, H),
+		DL(LD, IND, B),
 #undef DL
 	};
 
@@ -257,93 +257,93 @@  select_insn:
 
 	/* ALU */
 #define ALU(OPCODE, OP)			\
-	BPF_ALU64_##OPCODE##_BPF_X:	\
+	ALU64_##OPCODE##_X:		\
 		A = A OP X;		\
 		CONT;			\
-	BPF_ALU_##OPCODE##_BPF_X:	\
+	ALU_##OPCODE##_X:		\
 		A = (u32) A OP (u32) X;	\
 		CONT;			\
-	BPF_ALU64_##OPCODE##_BPF_K:	\
+	ALU64_##OPCODE##_K:		\
 		A = A OP K;		\
 		CONT;			\
-	BPF_ALU_##OPCODE##_BPF_K:	\
+	ALU_##OPCODE##_K:		\
 		A = (u32) A OP (u32) K;	\
 		CONT;
 
-	ALU(BPF_ADD,  +)
-	ALU(BPF_SUB,  -)
-	ALU(BPF_AND,  &)
-	ALU(BPF_OR,   |)
-	ALU(BPF_LSH, <<)
-	ALU(BPF_RSH, >>)
-	ALU(BPF_XOR,  ^)
-	ALU(BPF_MUL,  *)
+	ALU(ADD,  +)
+	ALU(SUB,  -)
+	ALU(AND,  &)
+	ALU(OR,   |)
+	ALU(LSH, <<)
+	ALU(RSH, >>)
+	ALU(XOR,  ^)
+	ALU(MUL,  *)
 #undef ALU
-	BPF_ALU_BPF_NEG_0:
+	ALU_NEG_0:
 		A = (u32) -A;
 		CONT;
-	BPF_ALU64_BPF_NEG_0:
+	ALU64_NEG_0:
 		A = -A;
 		CONT;
-	BPF_ALU_BPF_MOV_BPF_X:
+	ALU_MOV_X:
 		A = (u32) X;
 		CONT;
-	BPF_ALU_BPF_MOV_BPF_K:
+	ALU_MOV_K:
 		A = (u32) K;
 		CONT;
-	BPF_ALU64_BPF_MOV_BPF_X:
+	ALU64_MOV_X:
 		A = X;
 		CONT;
-	BPF_ALU64_BPF_MOV_BPF_K:
+	ALU64_MOV_K:
 		A = K;
 		CONT;
-	BPF_ALU64_BPF_ARSH_BPF_X:
+	ALU64_ARSH_X:
 		(*(s64 *) &A) >>= X;
 		CONT;
-	BPF_ALU64_BPF_ARSH_BPF_K:
+	ALU64_ARSH_K:
 		(*(s64 *) &A) >>= K;
 		CONT;
-	BPF_ALU64_BPF_MOD_BPF_X:
+	ALU64_MOD_X:
 		if (unlikely(X == 0))
 			return 0;
 		tmp = A;
 		A = do_div(tmp, X);
 		CONT;
-	BPF_ALU_BPF_MOD_BPF_X:
+	ALU_MOD_X:
 		if (unlikely(X == 0))
 			return 0;
 		tmp = (u32) A;
 		A = do_div(tmp, (u32) X);
 		CONT;
-	BPF_ALU64_BPF_MOD_BPF_K:
+	ALU64_MOD_K:
 		tmp = A;
 		A = do_div(tmp, K);
 		CONT;
-	BPF_ALU_BPF_MOD_BPF_K:
+	ALU_MOD_K:
 		tmp = (u32) A;
 		A = do_div(tmp, (u32) K);
 		CONT;
-	BPF_ALU64_BPF_DIV_BPF_X:
+	ALU64_DIV_X:
 		if (unlikely(X == 0))
 			return 0;
 		do_div(A, X);
 		CONT;
-	BPF_ALU_BPF_DIV_BPF_X:
+	ALU_DIV_X:
 		if (unlikely(X == 0))
 			return 0;
 		tmp = (u32) A;
 		do_div(tmp, (u32) X);
 		A = (u32) tmp;
 		CONT;
-	BPF_ALU64_BPF_DIV_BPF_K:
+	ALU64_DIV_K:
 		do_div(A, K);
 		CONT;
-	BPF_ALU_BPF_DIV_BPF_K:
+	ALU_DIV_K:
 		tmp = (u32) A;
 		do_div(tmp, (u32) K);
 		A = (u32) tmp;
 		CONT;
-	BPF_ALU_BPF_END_BPF_TO_BE:
+	ALU_END_TO_BE:
 		switch (K) {
 		case 16:
 			A = (__force u16) cpu_to_be16(A);
@@ -356,7 +356,7 @@  select_insn:
 			break;
 		}
 		CONT;
-	BPF_ALU_BPF_END_BPF_TO_LE:
+	ALU_END_TO_LE:
 		switch (K) {
 		case 16:
 			A = (__force u16) cpu_to_le16(A);
@@ -371,7 +371,7 @@  select_insn:
 		CONT;
 
 	/* CALL */
-	BPF_JMP_BPF_CALL_0:
+	JMP_CALL_0:
 		/* Function call scratches R1-R5 registers, preserves R6-R9,
 		 * and stores return value into R0.
 		 */
@@ -380,122 +380,122 @@  select_insn:
 		CONT;
 
 	/* JMP */
-	BPF_JMP_BPF_JA_0:
+	JMP_JA_0:
 		insn += insn->off;
 		CONT;
-	BPF_JMP_BPF_JEQ_BPF_X:
+	JMP_JEQ_X:
 		if (A == X) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JEQ_BPF_K:
+	JMP_JEQ_K:
 		if (A == K) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JNE_BPF_X:
+	JMP_JNE_X:
 		if (A != X) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JNE_BPF_K:
+	JMP_JNE_K:
 		if (A != K) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JGT_BPF_X:
+	JMP_JGT_X:
 		if (A > X) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JGT_BPF_K:
+	JMP_JGT_K:
 		if (A > K) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JGE_BPF_X:
+	JMP_JGE_X:
 		if (A >= X) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JGE_BPF_K:
+	JMP_JGE_K:
 		if (A >= K) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JSGT_BPF_X:
-		if (((s64)A) > ((s64)X)) {
+	JMP_JSGT_X:
+		if (((s64) A) > ((s64) X)) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JSGT_BPF_K:
-		if (((s64)A) > ((s64)K)) {
+	JMP_JSGT_K:
+		if (((s64) A) > ((s64) K)) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JSGE_BPF_X:
-		if (((s64)A) >= ((s64)X)) {
+	JMP_JSGE_X:
+		if (((s64) A) >= ((s64) X)) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JSGE_BPF_K:
-		if (((s64)A) >= ((s64)K)) {
+	JMP_JSGE_K:
+		if (((s64) A) >= ((s64) K)) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JSET_BPF_X:
+	JMP_JSET_X:
 		if (A & X) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_JSET_BPF_K:
+	JMP_JSET_K:
 		if (A & K) {
 			insn += insn->off;
 			CONT_JMP;
 		}
 		CONT;
-	BPF_JMP_BPF_EXIT_0:
+	JMP_EXIT_0:
 		return R0;
 
 	/* STX and ST and LDX*/
 #define LDST(SIZEOP, SIZE)					\
-	BPF_STX_BPF_MEM_##SIZEOP:				\
+	STX_MEM_##SIZEOP:					\
 		*(SIZE *)(unsigned long) (A + insn->off) = X;	\
 		CONT;						\
-	BPF_ST_BPF_MEM_##SIZEOP:				\
+	ST_MEM_##SIZEOP:					\
 		*(SIZE *)(unsigned long) (A + insn->off) = K;	\
 		CONT;						\
-	BPF_LDX_BPF_MEM_##SIZEOP:				\
+	LDX_MEM_##SIZEOP:					\
 		A = *(SIZE *)(unsigned long) (X + insn->off);	\
 		CONT;
 
-	LDST(BPF_B,   u8)
-	LDST(BPF_H,  u16)
-	LDST(BPF_W,  u32)
-	LDST(BPF_DW, u64)
+	LDST(B,   u8)
+	LDST(H,  u16)
+	LDST(W,  u32)
+	LDST(DW, u64)
 #undef LDST
-	BPF_STX_BPF_XADD_BPF_W: /* lock xadd *(u32 *)(A + insn->off) += X */
+	STX_XADD_W: /* lock xadd *(u32 *)(A + insn->off) += X */
 		atomic_add((u32) X, (atomic_t *)(unsigned long)
 			   (A + insn->off));
 		CONT;
-	BPF_STX_BPF_XADD_BPF_DW: /* lock xadd *(u64 *)(A + insn->off) += X */
+	STX_XADD_DW: /* lock xadd *(u64 *)(A + insn->off) += X */
 		atomic64_add((u64) X, (atomic64_t *)(unsigned long)
 			     (A + insn->off));
 		CONT;
-	BPF_LD_BPF_ABS_BPF_W: /* R0 = ntohl(*(u32 *) (skb->data + K)) */
+	LD_ABS_W: /* R0 = ntohl(*(u32 *) (skb->data + K)) */
 		off = K;
 load_word:
 		/* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are only
@@ -524,7 +524,7 @@  load_word:
 			CONT;
 		}
 		return 0;
-	BPF_LD_BPF_ABS_BPF_H: /* R0 = ntohs(*(u16 *) (skb->data + K)) */
+	LD_ABS_H: /* R0 = ntohs(*(u16 *) (skb->data + K)) */
 		off = K;
 load_half:
 		ptr = load_pointer((struct sk_buff *) ctx, off, 2, &tmp);
@@ -533,7 +533,7 @@  load_half:
 			CONT;
 		}
 		return 0;
-	BPF_LD_BPF_ABS_BPF_B: /* R0 = *(u8 *) (ctx + K) */
+	LD_ABS_B: /* R0 = *(u8 *) (ctx + K) */
 		off = K;
 load_byte:
 		ptr = load_pointer((struct sk_buff *) ctx, off, 1, &tmp);
@@ -542,13 +542,13 @@  load_byte:
 			CONT;
 		}
 		return 0;
-	BPF_LD_BPF_IND_BPF_W: /* R0 = ntohl(*(u32 *) (skb->data + X + K)) */
+	LD_IND_W: /* R0 = ntohl(*(u32 *) (skb->data + X + K)) */
 		off = K + X;
 		goto load_word;
-	BPF_LD_BPF_IND_BPF_H: /* R0 = ntohs(*(u16 *) (skb->data + X + K)) */
+	LD_IND_H: /* R0 = ntohs(*(u16 *) (skb->data + X + K)) */
 		off = K + X;
 		goto load_half;
-	BPF_LD_BPF_IND_BPF_B: /* R0 = *(u8 *) (skb->data + X + K) */
+	LD_IND_B: /* R0 = *(u8 *) (skb->data + X + K) */
 		off = K + X;
 		goto load_byte;