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path: root/arch/arm64/net/bpf_jit_comp.c
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Diffstat (limited to 'arch/arm64/net/bpf_jit_comp.c')
-rw-r--r--arch/arm64/net/bpf_jit_comp.c32
1 files changed, 18 insertions, 14 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index bd2ac9912087..f32144b2e07f 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -36,6 +36,7 @@ int bpf_jit_enable __read_mostly;
#define TMP_REG_1 (MAX_BPF_JIT_REG + 0)
#define TMP_REG_2 (MAX_BPF_JIT_REG + 1)
#define TCALL_CNT (MAX_BPF_JIT_REG + 2)
+#define TMP_REG_3 (MAX_BPF_JIT_REG + 3)
/* Map BPF registers to A64 registers */
static const int bpf2a64[] = {
@@ -57,6 +58,7 @@ static const int bpf2a64[] = {
/* temporary registers for internal BPF JIT */
[TMP_REG_1] = A64_R(10),
[TMP_REG_2] = A64_R(11),
+ [TMP_REG_3] = A64_R(12),
/* tail_call_cnt */
[TCALL_CNT] = A64_R(26),
/* temporary register for blinding constants */
@@ -69,6 +71,7 @@ struct jit_ctx {
int epilogue_offset;
int *offset;
__le32 *image;
+ u32 stack_size;
};
static inline void emit(const u32 insn, struct jit_ctx *ctx)
@@ -145,16 +148,11 @@ static inline int epilogue_offset(const struct jit_ctx *ctx)
/* Stack must be multiples of 16B */
#define STACK_ALIGN(sz) (((sz) + 15) & ~15)
-#define _STACK_SIZE \
- (MAX_BPF_STACK \
- + 4 /* extra for skb_copy_bits buffer */)
-
-#define STACK_SIZE STACK_ALIGN(_STACK_SIZE)
-
#define PROLOGUE_OFFSET 8
static int build_prologue(struct jit_ctx *ctx)
{
+ const struct bpf_prog *prog = ctx->prog;
const u8 r6 = bpf2a64[BPF_REG_6];
const u8 r7 = bpf2a64[BPF_REG_7];
const u8 r8 = bpf2a64[BPF_REG_8];
@@ -176,9 +174,9 @@ static int build_prologue(struct jit_ctx *ctx)
* | |
* | ... | BPF prog stack
* | |
- * +-----+ <= (BPF_FP - MAX_BPF_STACK)
+ * +-----+ <= (BPF_FP - prog->aux->stack_depth)
* |RSVD | JIT scratchpad
- * current A64_SP => +-----+ <= (BPF_FP - STACK_SIZE)
+ * current A64_SP => +-----+ <= (BPF_FP - ctx->stack_size)
* | |
* | ... | Function call stack
* | |
@@ -202,8 +200,12 @@ static int build_prologue(struct jit_ctx *ctx)
/* Initialize tail_call_cnt */
emit(A64_MOVZ(1, tcc, 0, 0), ctx);
+ /* 4 byte extra for skb_copy_bits buffer */
+ ctx->stack_size = prog->aux->stack_depth + 4;
+ ctx->stack_size = STACK_ALIGN(ctx->stack_size);
+
/* Set up function call stack */
- emit(A64_SUB_I(1, A64_SP, A64_SP, STACK_SIZE), ctx);
+ emit(A64_SUB_I(1, A64_SP, A64_SP, ctx->stack_size), ctx);
cur_offset = ctx->idx - idx0;
if (cur_offset != PROLOGUE_OFFSET) {
@@ -288,7 +290,7 @@ static void build_epilogue(struct jit_ctx *ctx)
const u8 fp = bpf2a64[BPF_REG_FP];
/* We're done with BPF stack */
- emit(A64_ADD_I(1, A64_SP, A64_SP, STACK_SIZE), ctx);
+ emit(A64_ADD_I(1, A64_SP, A64_SP, ctx->stack_size), ctx);
/* Restore fs (x25) and x26 */
emit(A64_POP(fp, A64_R(26), A64_SP), ctx);
@@ -319,6 +321,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
const u8 src = bpf2a64[insn->src_reg];
const u8 tmp = bpf2a64[TMP_REG_1];
const u8 tmp2 = bpf2a64[TMP_REG_2];
+ const u8 tmp3 = bpf2a64[TMP_REG_3];
const s16 off = insn->off;
const s32 imm = insn->imm;
const int i = insn - ctx->prog->insnsi;
@@ -586,7 +589,7 @@ emit_cond_jmp:
break;
}
/* tail call */
- case BPF_JMP | BPF_CALL | BPF_X:
+ case BPF_JMP | BPF_TAIL_CALL:
if (emit_bpf_tail_call(ctx))
return -EFAULT;
break;
@@ -689,10 +692,10 @@ emit_cond_jmp:
emit(A64_PRFM(tmp, PST, L1, STRM), ctx);
emit(A64_LDXR(isdw, tmp2, tmp), ctx);
emit(A64_ADD(isdw, tmp2, tmp2, src), ctx);
- emit(A64_STXR(isdw, tmp2, tmp, tmp2), ctx);
+ emit(A64_STXR(isdw, tmp2, tmp, tmp3), ctx);
jmp_offset = -3;
check_imm19(jmp_offset);
- emit(A64_CBNZ(0, tmp2, jmp_offset), ctx);
+ emit(A64_CBNZ(0, tmp3, jmp_offset), ctx);
break;
/* R0 = ntohx(*(size *)(((struct sk_buff *)R6)->data + imm)) */
@@ -732,7 +735,7 @@ emit_cond_jmp:
return -EINVAL;
}
emit_a64_mov_i64(r3, size, ctx);
- emit(A64_SUB_I(1, r4, fp, STACK_SIZE), ctx);
+ emit(A64_SUB_I(1, r4, fp, ctx->stack_size), ctx);
emit_a64_mov_i64(r5, (unsigned long)bpf_load_pointer, ctx);
emit(A64_BLR(r5), ctx);
emit(A64_MOV(1, r0, A64_R(0)), ctx);
@@ -900,6 +903,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
bpf_jit_binary_lock_ro(header);
prog->bpf_func = (void *)ctx.image;
prog->jited = 1;
+ prog->jited_len = image_size;
out_off:
kfree(ctx.offset);