ARM: net: add support for BPF_ANC | SKF_AD_HATYPE in ARM JIT.

Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index 3c73caf..876060b 100644 (file)
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -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);
-                       off = offsetof(struct net_device, ifindex);
-                       emit(ARM_LDR_I(r_A, r_scratch, off), ctx);
+                       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;

diff --git a/arch/arm/net/bpf_jit_32.h b/arch/arm/net/bpf_jit_32.h
index b2d7d92..4b17d5a 100644 (file)
--- a/arch/arm/net/bpf_jit_32.h
+++ b/arch/arm/net/bpf_jit_32.h
@@ -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))