Commit 0b42c286 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'arm-bpf-next' 



Nicolas Schichan says:

====================
ARM BPF JIT features

This series adds support for more instructions to the ARM BPF JIT
namely skb netdevice type retrieval, skb payload offset retrieval, and
skb packet type retrieval.

This allows 35 tests to use the JIT instead of 29 before.

This series depends on the "BPF JIT fixes for ARM" serie sent earlier.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents e11f40b9 5bf705b4

arch/arm/net/bpf_jit_32.c

+39 −2
Original line number Diff line number Diff line
@@ -857,7 +857,9 @@ b_epilogue: 
			emit(ARM_LDR_I(r_A, r_scratch, off), ctx);

			break;

		case BPF_ANC | SKF_AD_IFINDEX:

		case BPF_ANC | SKF_AD_HATYPE:

			/* A = skb->dev->ifindex */

			/* A = skb->dev->type */

			ctx->seen |= SEEN_SKB;

			off = offsetof(struct sk_buff, dev);

			emit(ARM_LDR_I(r_scratch, r_skb, off), ctx);
@@ -867,8 +869,24 @@ b_epilogue: 


			BUILD_BUG_ON(FIELD_SIZEOF(struct net_device,

						  ifindex) != 4);

			BUILD_BUG_ON(FIELD_SIZEOF(struct net_device,

						  type) != 2);



			if (code == (BPF_ANC | SKF_AD_IFINDEX)) {

				off = offsetof(struct net_device, ifindex);

				emit(ARM_LDR_I(r_A, r_scratch, off), ctx);

			} else {

				/*

				 * offset of field "type" in "struct

				 * net_device" is above what can be

				 * used in the ldrh rd, [rn, #imm]

				 * instruction, so load the offset in

				 * a register and use ldrh rd, [rn, rm]

				 */

				off = offsetof(struct net_device, type);

				emit_mov_i(ARM_R3, off, ctx);

				emit(ARM_LDRH_R(r_A, r_scratch, ARM_R3), ctx);

			}

			break;

		case BPF_ANC | SKF_AD_MARK:

			ctx->seen |= SEEN_SKB;
@@ -895,6 +913,17 @@ b_epilogue: 
				OP_IMM3(ARM_AND, r_A, r_A, 0x1, ctx);

			}

			break;

		case BPF_ANC | SKF_AD_PKTTYPE:

			ctx->seen |= SEEN_SKB;

			BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff,

						  __pkt_type_offset[0]) != 1);

			off = PKT_TYPE_OFFSET();

			emit(ARM_LDRB_I(r_A, r_skb, off), ctx);

			emit(ARM_AND_I(r_A, r_A, PKT_TYPE_MAX), ctx);

#ifdef __BIG_ENDIAN_BITFIELD

			emit(ARM_LSR_I(r_A, r_A, 5), ctx);

#endif

			break;

		case BPF_ANC | SKF_AD_QUEUE:

			ctx->seen |= SEEN_SKB;

			BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff,
@@ -904,6 +933,14 @@ b_epilogue: 
			off = offsetof(struct sk_buff, queue_mapping);

			emit(ARM_LDRH_I(r_A, r_skb, off), ctx);

			break;

		case BPF_ANC | SKF_AD_PAY_OFFSET:

			ctx->seen |= SEEN_SKB | SEEN_CALL;



			emit(ARM_MOV_R(ARM_R0, r_skb), ctx);

			emit_mov_i(ARM_R3, (unsigned int)skb_get_poff, ctx);

			emit_blx_r(ARM_R3, ctx);

			emit(ARM_MOV_R(r_A, ARM_R0), ctx);

			break;

		case BPF_LDX | BPF_W | BPF_ABS:

			/*

			 * load a 32bit word from struct seccomp_data.

arch/arm/net/bpf_jit_32.h

+3 −0
Original line number Diff line number Diff line
@@ -74,6 +74,7 @@ 
#define ARM_INST_LDRB_I		0x05d00000

#define ARM_INST_LDRB_R		0x07d00000

#define ARM_INST_LDRH_I		0x01d000b0

#define ARM_INST_LDRH_R		0x019000b0

#define ARM_INST_LDR_I		0x05900000



#define ARM_INST_LDM		0x08900000
@@ -160,6 +161,8 @@ 
				 | (rm))

#define ARM_LDRH_I(rt, rn, off)	(ARM_INST_LDRH_I | (rt) << 12 | (rn) << 16 \

				 | (((off) & 0xf0) << 4) | ((off) & 0xf))

#define ARM_LDRH_R(rt, rn, rm)	(ARM_INST_LDRH_R | (rt) << 12 | (rn) << 16 \

				 | (rm))



#define ARM_LDM(rn, regs)	(ARM_INST_LDM | (rn) << 16 | (regs))

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