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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.c49
1 files changed, 32 insertions, 17 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index 5db82bfc9dc1..66708b95493a 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -19,7 +19,7 @@
#include <asm/cacheflush.h>
#include <asm/debug-monitors.h>
#include <asm/insn.h>
-#include <asm/patching.h>
+#include <asm/text-patching.h>
#include <asm/set_memory.h>
#include "bpf_jit.h"
@@ -2094,6 +2094,12 @@ static void restore_args(struct jit_ctx *ctx, int args_off, int nregs)
}
}
+static bool is_struct_ops_tramp(const struct bpf_tramp_links *fentry_links)
+{
+ return fentry_links->nr_links == 1 &&
+ fentry_links->links[0]->link.type == BPF_LINK_TYPE_STRUCT_OPS;
+}
+
/* Based on the x86's implementation of arch_prepare_bpf_trampoline().
*
* bpf prog and function entry before bpf trampoline hooked:
@@ -2123,6 +2129,7 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
bool save_ret;
__le32 **branches = NULL;
+ bool is_struct_ops = is_struct_ops_tramp(fentry);
/* trampoline stack layout:
* [ parent ip ]
@@ -2191,11 +2198,14 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
*/
emit_bti(A64_BTI_JC, ctx);
- /* frame for parent function */
- emit(A64_PUSH(A64_FP, A64_R(9), A64_SP), ctx);
- emit(A64_MOV(1, A64_FP, A64_SP), ctx);
+ /* x9 is not set for struct_ops */
+ if (!is_struct_ops) {
+ /* frame for parent function */
+ emit(A64_PUSH(A64_FP, A64_R(9), A64_SP), ctx);
+ emit(A64_MOV(1, A64_FP, A64_SP), ctx);
+ }
- /* frame for patched function */
+ /* frame for patched function for tracing, or caller for struct_ops */
emit(A64_PUSH(A64_FP, A64_LR, A64_SP), ctx);
emit(A64_MOV(1, A64_FP, A64_SP), ctx);
@@ -2289,19 +2299,24 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
/* reset SP */
emit(A64_MOV(1, A64_SP, A64_FP), ctx);
- /* pop frames */
- emit(A64_POP(A64_FP, A64_LR, A64_SP), ctx);
- emit(A64_POP(A64_FP, A64_R(9), A64_SP), ctx);
-
- if (flags & BPF_TRAMP_F_SKIP_FRAME) {
- /* skip patched function, return to parent */
- emit(A64_MOV(1, A64_LR, A64_R(9)), ctx);
- emit(A64_RET(A64_R(9)), ctx);
+ if (is_struct_ops) {
+ emit(A64_POP(A64_FP, A64_LR, A64_SP), ctx);
+ emit(A64_RET(A64_LR), ctx);
} else {
- /* return to patched function */
- emit(A64_MOV(1, A64_R(10), A64_LR), ctx);
- emit(A64_MOV(1, A64_LR, A64_R(9)), ctx);
- emit(A64_RET(A64_R(10)), ctx);
+ /* pop frames */
+ emit(A64_POP(A64_FP, A64_LR, A64_SP), ctx);
+ emit(A64_POP(A64_FP, A64_R(9), A64_SP), ctx);
+
+ if (flags & BPF_TRAMP_F_SKIP_FRAME) {
+ /* skip patched function, return to parent */
+ emit(A64_MOV(1, A64_LR, A64_R(9)), ctx);
+ emit(A64_RET(A64_R(9)), ctx);
+ } else {
+ /* return to patched function */
+ emit(A64_MOV(1, A64_R(10), A64_LR), ctx);
+ emit(A64_MOV(1, A64_LR, A64_R(9)), ctx);
+ emit(A64_RET(A64_R(10)), ctx);
+ }
}
kfree(branches);