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Diffstat (limited to 'arch/loongarch/net/bpf_jit.c')
-rw-r--r--arch/loongarch/net/bpf_jit.c86
1 files changed, 61 insertions, 25 deletions
diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c
index abfdb6bb5c38..cbe53d0b7fb0 100644
--- a/arch/loongarch/net/bpf_jit.c
+++ b/arch/loongarch/net/bpf_jit.c
@@ -527,13 +527,11 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool ext
emit_zext_32(ctx, dst, is32);
break;
case 8:
- move_reg(ctx, t1, src);
- emit_insn(ctx, extwb, dst, t1);
+ emit_insn(ctx, extwb, dst, src);
emit_zext_32(ctx, dst, is32);
break;
case 16:
- move_reg(ctx, t1, src);
- emit_insn(ctx, extwh, dst, t1);
+ emit_insn(ctx, extwh, dst, src);
emit_zext_32(ctx, dst, is32);
break;
case 32:
@@ -1294,8 +1292,10 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type poke_type,
u32 old_insns[LOONGARCH_LONG_JUMP_NINSNS] = {[0 ... 4] = INSN_NOP};
u32 new_insns[LOONGARCH_LONG_JUMP_NINSNS] = {[0 ... 4] = INSN_NOP};
- if (!is_kernel_text((unsigned long)ip) &&
- !is_bpf_text_address((unsigned long)ip))
+ /* Only poking bpf text is supported. Since kernel function entry
+ * is set up by ftrace, we rely on ftrace to poke kernel functions.
+ */
+ if (!is_bpf_text_address((unsigned long)ip))
return -ENOTSUPP;
ret = emit_jump_or_nops(old_addr, ip, old_insns, is_call);
@@ -1448,12 +1448,43 @@ void arch_free_bpf_trampoline(void *image, unsigned int size)
bpf_prog_pack_free(image, size);
}
+/*
+ * Sign-extend the register if necessary
+ */
+static void sign_extend(struct jit_ctx *ctx, int rd, int rj, u8 size, bool sign)
+{
+ /* ABI requires unsigned char/short to be zero-extended */
+ if (!sign && (size == 1 || size == 2)) {
+ if (rd != rj)
+ move_reg(ctx, rd, rj);
+ return;
+ }
+
+ switch (size) {
+ case 1:
+ emit_insn(ctx, extwb, rd, rj);
+ break;
+ case 2:
+ emit_insn(ctx, extwh, rd, rj);
+ break;
+ case 4:
+ emit_insn(ctx, addiw, rd, rj, 0);
+ break;
+ case 8:
+ if (rd != rj)
+ move_reg(ctx, rd, rj);
+ break;
+ default:
+ pr_warn("bpf_jit: invalid size %d for sign_extend\n", size);
+ }
+}
+
static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
const struct btf_func_model *m, struct bpf_tramp_links *tlinks,
void *func_addr, u32 flags)
{
int i, ret, save_ret;
- int stack_size = 0, nargs = 0;
+ int stack_size, nargs;
int retval_off, args_off, nargs_off, ip_off, run_ctx_off, sreg_off, tcc_ptr_off;
bool is_struct_ops = flags & BPF_TRAMP_F_INDIRECT;
void *orig_call = func_addr;
@@ -1462,9 +1493,6 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
u32 **branches = NULL;
- if (flags & (BPF_TRAMP_F_ORIG_STACK | BPF_TRAMP_F_SHARE_IPMODIFY))
- return -ENOTSUPP;
-
/*
* FP + 8 [ RA to parent func ] return address to parent
* function
@@ -1495,20 +1523,23 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
if (m->nr_args > LOONGARCH_MAX_REG_ARGS)
return -ENOTSUPP;
+ /* FIXME: No support of struct argument */
+ for (i = 0; i < m->nr_args; i++) {
+ if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG)
+ return -ENOTSUPP;
+ }
+
if (flags & (BPF_TRAMP_F_ORIG_STACK | BPF_TRAMP_F_SHARE_IPMODIFY))
return -ENOTSUPP;
- stack_size = 0;
-
/* Room of trampoline frame to store return address and frame pointer */
- stack_size += 16;
+ stack_size = 16;
save_ret = flags & (BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_RET_FENTRY_RET);
- if (save_ret) {
- /* Save BPF R0 and A0 */
- stack_size += 16;
- retval_off = stack_size;
- }
+ if (save_ret)
+ stack_size += 16; /* Save BPF R0 and A0 */
+
+ retval_off = stack_size;
/* Room of trampoline frame to store args */
nargs = m->nr_args;
@@ -1595,7 +1626,7 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
orig_call += LOONGARCH_BPF_FENTRY_NBYTES;
if (flags & BPF_TRAMP_F_CALL_ORIG) {
- move_imm(ctx, LOONGARCH_GPR_A0, (const s64)im, false);
+ move_addr(ctx, LOONGARCH_GPR_A0, (const u64)im);
ret = emit_call(ctx, (const u64)__bpf_tramp_enter);
if (ret)
return ret;
@@ -1645,7 +1676,7 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
if (flags & BPF_TRAMP_F_CALL_ORIG) {
im->ip_epilogue = ctx->ro_image + ctx->idx;
- move_imm(ctx, LOONGARCH_GPR_A0, (const s64)im, false);
+ move_addr(ctx, LOONGARCH_GPR_A0, (const u64)im);
ret = emit_call(ctx, (const u64)__bpf_tramp_exit);
if (ret)
goto out;
@@ -1655,8 +1686,12 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
restore_args(ctx, m->nr_args, args_off);
if (save_ret) {
- emit_insn(ctx, ldd, LOONGARCH_GPR_A0, LOONGARCH_GPR_FP, -retval_off);
emit_insn(ctx, ldd, regmap[BPF_REG_0], LOONGARCH_GPR_FP, -(retval_off - 8));
+ if (is_struct_ops)
+ sign_extend(ctx, LOONGARCH_GPR_A0, regmap[BPF_REG_0],
+ m->ret_size, m->ret_flags & BTF_FMODEL_SIGNED_ARG);
+ else
+ emit_insn(ctx, ldd, LOONGARCH_GPR_A0, LOONGARCH_GPR_FP, -retval_off);
}
emit_insn(ctx, ldd, LOONGARCH_GPR_S1, LOONGARCH_GPR_FP, -sreg_off);
@@ -1715,7 +1750,10 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
jit_fill_hole(image, (unsigned int)(ro_image_end - ro_image));
ret = __arch_prepare_bpf_trampoline(&ctx, im, m, tlinks, func_addr, flags);
- if (ret > 0 && validate_code(&ctx) < 0) {
+ if (ret < 0)
+ goto out;
+
+ if (validate_code(&ctx) < 0) {
ret = -EINVAL;
goto out;
}
@@ -1726,7 +1764,6 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
goto out;
}
- bpf_flush_icache(ro_image, ro_image_end);
out:
kvfree(image);
return ret < 0 ? ret : size;
@@ -1744,8 +1781,7 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
ret = __arch_prepare_bpf_trampoline(&ctx, &im, m, tlinks, func_addr, flags);
- /* Page align */
- return ret < 0 ? ret : round_up(ret * LOONGARCH_INSN_SIZE, PAGE_SIZE);
+ return ret < 0 ? ret : ret * LOONGARCH_INSN_SIZE;
}
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
generated by cgit (git 2.34.1) at 2025-10-07 13:06:06 +0000