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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.c106
1 files changed, 77 insertions, 29 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index ba38d403abb2..1d4f1da7c58f 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -31,8 +31,6 @@
#include "bpf_jit.h"
-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)
@@ -99,6 +97,20 @@ static inline void emit_a64_mov_i64(const int reg, const u64 val,
}
}
+static inline void emit_addr_mov_i64(const int reg, const u64 val,
+ struct jit_ctx *ctx)
+{
+ u64 tmp = val;
+ int shift = 0;
+
+ emit(A64_MOVZ(1, reg, tmp & 0xffff, shift), ctx);
+ for (;shift < 48;) {
+ tmp >>= 16;
+ shift += 16;
+ emit(A64_MOVK(1, reg, tmp & 0xffff, shift), ctx);
+ }
+}
+
static inline void emit_a64_mov_i(const int is64, const int reg,
const s32 val, struct jit_ctx *ctx)
{
@@ -148,7 +160,8 @@ static inline int epilogue_offset(const struct jit_ctx *ctx)
/* Stack must be multiples of 16B */
#define STACK_ALIGN(sz) (((sz) + 15) & ~15)
-#define PROLOGUE_OFFSET 8
+/* Tail call offset to jump into */
+#define PROLOGUE_OFFSET 7
static int build_prologue(struct jit_ctx *ctx)
{
@@ -200,19 +213,19 @@ 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, ctx->stack_size), ctx);
-
cur_offset = ctx->idx - idx0;
if (cur_offset != PROLOGUE_OFFSET) {
pr_err_once("PROLOGUE_OFFSET = %d, expected %d!\n",
cur_offset, PROLOGUE_OFFSET);
return -1;
}
+
+ /* 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, ctx->stack_size), ctx);
return 0;
}
@@ -260,11 +273,12 @@ static int emit_bpf_tail_call(struct jit_ctx *ctx)
emit(A64_LDR64(prg, tmp, prg), ctx);
emit(A64_CBZ(1, prg, jmp_offset), ctx);
- /* goto *(prog->bpf_func + prologue_size); */
+ /* goto *(prog->bpf_func + prologue_offset); */
off = offsetof(struct bpf_prog, bpf_func);
emit_a64_mov_i64(tmp, off, ctx);
emit(A64_LDR64(tmp, prg, tmp), ctx);
emit(A64_ADD_I(1, tmp, tmp, sizeof(u32) * PROLOGUE_OFFSET), ctx);
+ emit(A64_ADD_I(1, A64_SP, A64_SP, ctx->stack_size), ctx);
emit(A64_BR(tmp), ctx);
/* out: */
@@ -376,18 +390,6 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
case BPF_ALU64 | BPF_DIV | BPF_X:
case BPF_ALU | BPF_MOD | BPF_X:
case BPF_ALU64 | BPF_MOD | BPF_X:
- {
- const u8 r0 = bpf2a64[BPF_REG_0];
-
- /* if (src == 0) return 0 */
- jmp_offset = 3; /* skip ahead to else path */
- check_imm19(jmp_offset);
- emit(A64_CBNZ(is64, src, jmp_offset), ctx);
- emit(A64_MOVZ(1, r0, 0, 0), ctx);
- jmp_offset = epilogue_offset(ctx);
- check_imm26(jmp_offset);
- emit(A64_B(jmp_offset), ctx);
- /* else */
switch (BPF_OP(code)) {
case BPF_DIV:
emit(A64_UDIV(is64, dst, dst, src), ctx);
@@ -399,7 +401,6 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
break;
}
break;
- }
case BPF_ALU | BPF_LSH | BPF_X:
case BPF_ALU64 | BPF_LSH | BPF_X:
emit(A64_LSLV(is64, dst, dst, src), ctx);
@@ -603,7 +604,10 @@ emit_cond_jmp:
const u8 r0 = bpf2a64[BPF_REG_0];
const u64 func = (u64)__bpf_call_base + imm;
- emit_a64_mov_i64(tmp, func, ctx);
+ if (ctx->prog->is_func)
+ emit_addr_mov_i64(tmp, func, ctx);
+ else
+ emit_a64_mov_i64(tmp, func, ctx);
emit(A64_BLR(tmp), ctx);
emit(A64_MOV(1, r0, A64_R(0)), ctx);
break;
@@ -835,16 +839,24 @@ static inline void bpf_flush_icache(void *start, void *end)
flush_icache_range((unsigned long)start, (unsigned long)end);
}
+struct arm64_jit_data {
+ struct bpf_binary_header *header;
+ u8 *image;
+ struct jit_ctx ctx;
+};
+
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
struct bpf_prog *tmp, *orig_prog = prog;
struct bpf_binary_header *header;
+ struct arm64_jit_data *jit_data;
bool tmp_blinded = false;
+ bool extra_pass = false;
struct jit_ctx ctx;
int image_size;
u8 *image_ptr;
- if (!bpf_jit_enable)
+ if (!prog->jit_requested)
return orig_prog;
tmp = bpf_jit_blind_constants(prog);
@@ -858,13 +870,30 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
prog = tmp;
}
+ jit_data = prog->aux->jit_data;
+ if (!jit_data) {
+ jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL);
+ if (!jit_data) {
+ prog = orig_prog;
+ goto out;
+ }
+ prog->aux->jit_data = jit_data;
+ }
+ if (jit_data->ctx.offset) {
+ ctx = jit_data->ctx;
+ image_ptr = jit_data->image;
+ header = jit_data->header;
+ extra_pass = true;
+ image_size = sizeof(u32) * ctx.idx;
+ goto skip_init_ctx;
+ }
memset(&ctx, 0, sizeof(ctx));
ctx.prog = prog;
ctx.offset = kcalloc(prog->len, sizeof(int), GFP_KERNEL);
if (ctx.offset == NULL) {
prog = orig_prog;
- goto out;
+ goto out_off;
}
/* 1. Initial fake pass to compute ctx->idx. */
@@ -895,6 +924,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
/* 2. Now, the actual pass. */
ctx.image = (__le32 *)image_ptr;
+skip_init_ctx:
ctx.idx = 0;
build_prologue(&ctx);
@@ -920,13 +950,31 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
bpf_flush_icache(header, ctx.image + ctx.idx);
- bpf_jit_binary_lock_ro(header);
+ if (!prog->is_func || extra_pass) {
+ if (extra_pass && ctx.idx != jit_data->ctx.idx) {
+ pr_err_once("multi-func JIT bug %d != %d\n",
+ ctx.idx, jit_data->ctx.idx);
+ bpf_jit_binary_free(header);
+ prog->bpf_func = NULL;
+ prog->jited = 0;
+ goto out_off;
+ }
+ bpf_jit_binary_lock_ro(header);
+ } else {
+ jit_data->ctx = ctx;
+ jit_data->image = image_ptr;
+ jit_data->header = header;
+ }
prog->bpf_func = (void *)ctx.image;
prog->jited = 1;
prog->jited_len = image_size;
+ if (!prog->is_func || extra_pass) {
out_off:
- kfree(ctx.offset);
+ kfree(ctx.offset);
+ kfree(jit_data);
+ prog->aux->jit_data = NULL;
+ }
out:
if (tmp_blinded)
bpf_jit_prog_release_other(prog, prog == orig_prog ?
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-22 03:44:43 +0300