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Diffstat (limited to 'arch/powerpc/net/bpf_jit_comp64.c')
-rw-r--r--arch/powerpc/net/bpf_jit_comp64.c110
1 files changed, 89 insertions, 21 deletions
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index 1bdb1aff0619..f1c95779843b 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -167,25 +167,37 @@ static void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx)
static void bpf_jit_emit_func_call(u32 *image, struct codegen_context *ctx, u64 func)
{
+ unsigned int i, ctx_idx = ctx->idx;
+
+ /* Load function address into r12 */
+ PPC_LI64(12, func);
+
+ /* For bpf-to-bpf function calls, the callee's address is unknown
+ * until the last extra pass. As seen above, we use PPC_LI64() to
+ * load the callee's address, but this may optimize the number of
+ * instructions required based on the nature of the address.
+ *
+ * Since we don't want the number of instructions emitted to change,
+ * we pad the optimized PPC_LI64() call with NOPs to guarantee that
+ * we always have a five-instruction sequence, which is the maximum
+ * that PPC_LI64() can emit.
+ */
+ for (i = ctx->idx - ctx_idx; i < 5; i++)
+ PPC_NOP();
+
#ifdef PPC64_ELF_ABI_v1
- /* func points to the function descriptor */
- PPC_LI64(b2p[TMP_REG_2], func);
- /* Load actual entry point from function descriptor */
- PPC_BPF_LL(b2p[TMP_REG_1], b2p[TMP_REG_2], 0);
- /* ... and move it to LR */
- PPC_MTLR(b2p[TMP_REG_1]);
/*
* Load TOC from function descriptor at offset 8.
* We can clobber r2 since we get called through a
* function pointer (so caller will save/restore r2)
* and since we don't use a TOC ourself.
*/
- PPC_BPF_LL(2, b2p[TMP_REG_2], 8);
-#else
- /* We can clobber r12 */
- PPC_FUNC_ADDR(12, func);
- PPC_MTLR(12);
+ PPC_BPF_LL(2, 12, 8);
+ /* Load actual entry point from function descriptor */
+ PPC_BPF_LL(12, 12, 0);
#endif
+
+ PPC_MTLR(12);
PPC_BLRL();
}
@@ -256,7 +268,7 @@ static void bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32
/* Assemble the body code between the prologue & epilogue */
static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
struct codegen_context *ctx,
- u32 *addrs)
+ u32 *addrs, bool extra_pass)
{
const struct bpf_insn *insn = fp->insnsi;
int flen = fp->len;
@@ -712,11 +724,25 @@ emit_clear:
break;
/*
- * Call kernel helper
+ * Call kernel helper or bpf function
*/
case BPF_JMP | BPF_CALL:
ctx->seen |= SEEN_FUNC;
- func = (u8 *) __bpf_call_base + imm;
+
+ /* bpf function call */
+ if (insn[i].src_reg == BPF_PSEUDO_CALL)
+ if (!extra_pass)
+ func = NULL;
+ else if (fp->aux->func && off < fp->aux->func_cnt)
+ /* use the subprog id from the off
+ * field to lookup the callee address
+ */
+ func = (u8 *) fp->aux->func[off]->bpf_func;
+ else
+ return -EINVAL;
+ /* kernel helper call */
+ else
+ func = (u8 *) __bpf_call_base + imm;
bpf_jit_emit_func_call(image, ctx, (u64)func);
@@ -864,6 +890,14 @@ cond_branch:
return 0;
}
+struct powerpc64_jit_data {
+ struct bpf_binary_header *header;
+ u32 *addrs;
+ u8 *image;
+ u32 proglen;
+ struct codegen_context ctx;
+};
+
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
{
u32 proglen;
@@ -871,6 +905,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
u8 *image = NULL;
u32 *code_base;
u32 *addrs;
+ struct powerpc64_jit_data *jit_data;
struct codegen_context cgctx;
int pass;
int flen;
@@ -878,6 +913,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
struct bpf_prog *org_fp = fp;
struct bpf_prog *tmp_fp;
bool bpf_blinded = false;
+ bool extra_pass = false;
if (!fp->jit_requested)
return org_fp;
@@ -891,11 +927,32 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
fp = tmp_fp;
}
+ jit_data = fp->aux->jit_data;
+ if (!jit_data) {
+ jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL);
+ if (!jit_data) {
+ fp = org_fp;
+ goto out;
+ }
+ fp->aux->jit_data = jit_data;
+ }
+
flen = fp->len;
+ addrs = jit_data->addrs;
+ if (addrs) {
+ cgctx = jit_data->ctx;
+ image = jit_data->image;
+ bpf_hdr = jit_data->header;
+ proglen = jit_data->proglen;
+ alloclen = proglen + FUNCTION_DESCR_SIZE;
+ extra_pass = true;
+ goto skip_init_ctx;
+ }
+
addrs = kzalloc((flen+1) * sizeof(*addrs), GFP_KERNEL);
if (addrs == NULL) {
fp = org_fp;
- goto out;
+ goto out_addrs;
}
memset(&cgctx, 0, sizeof(struct codegen_context));
@@ -904,10 +961,10 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
cgctx.stack_size = round_up(fp->aux->stack_depth, 16);
/* Scouting faux-generate pass 0 */
- if (bpf_jit_build_body(fp, 0, &cgctx, addrs)) {
+ if (bpf_jit_build_body(fp, 0, &cgctx, addrs, false)) {
/* We hit something illegal or unsupported. */
fp = org_fp;
- goto out;
+ goto out_addrs;
}
/*
@@ -925,9 +982,10 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
bpf_jit_fill_ill_insns);
if (!bpf_hdr) {
fp = org_fp;
- goto out;
+ goto out_addrs;
}
+skip_init_ctx:
code_base = (u32 *)(image + FUNCTION_DESCR_SIZE);
/* Code generation passes 1-2 */
@@ -935,7 +993,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
/* Now build the prologue, body code & epilogue for real. */
cgctx.idx = 0;
bpf_jit_build_prologue(code_base, &cgctx);
- bpf_jit_build_body(fp, code_base, &cgctx, addrs);
+ bpf_jit_build_body(fp, code_base, &cgctx, addrs, extra_pass);
bpf_jit_build_epilogue(code_base, &cgctx);
if (bpf_jit_enable > 1)
@@ -961,10 +1019,20 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
fp->jited_len = alloclen;
bpf_flush_icache(bpf_hdr, (u8 *)bpf_hdr + (bpf_hdr->pages * PAGE_SIZE));
+ if (!fp->is_func || extra_pass) {
+out_addrs:
+ kfree(addrs);
+ kfree(jit_data);
+ fp->aux->jit_data = NULL;
+ } else {
+ jit_data->addrs = addrs;
+ jit_data->ctx = cgctx;
+ jit_data->proglen = proglen;
+ jit_data->image = image;
+ jit_data->header = bpf_hdr;
+ }
out:
- kfree(addrs);
-
if (bpf_blinded)
bpf_jit_prog_release_other(fp, fp == org_fp ? tmp_fp : org_fp);
generated by cgit v1.2.3 (git 2.25.1) at 2025-12-15 14:55:16 +0000