xref: /linux/arch/loongarch/net/bpf_timed_may_goto.S (revision caf325ab81be0bc22adf75248ecd22f52f01ad21)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Author: George Guo <guodongtai@kylinos.cn>
4 * Copyright (C) 2026 KylinSoft Corporation.
5 */
6
7#include <asm/asmmacro.h>
8#include <asm/regdef.h>
9#include <linux/export.h>
10#include <linux/linkage.h>
11
12SYM_FUNC_START(arch_bpf_timed_may_goto)
13	addi.d		sp, sp, -64
14	st.d		ra, sp, 56
15
16	/* Save BPF registers R0 - R5 (a5, a0 - a4) */
17	st.d		a5, sp, 8
18	st.d		a0, sp, 16
19	st.d		a1, sp, 24
20	st.d		a2, sp, 32
21	st.d		a3, sp, 40
22	st.d		a4, sp, 48
23
24	/*
25	 * BPF_REG_AX (t0) holds the offset passed in by the verifier;
26	 * add it to BPF_REG_FP (s4) to get the pointer to the count and
27	 * timestamp, then pass it as the first argument in a0.
28	 *
29	 * The verifier emits a load using FP right before this call,
30	 * so BPF_REG_FP (s4) is always set up by the JIT in this case.
31	 */
32	add.d		a0, t0, s4
33	bl		bpf_check_timed_may_goto
34	/* BPF_REG_AX (t0) will be stored into count, so move the return value to it. */
35	move		t0, a0
36
37	ld.d		ra, sp, 56
38	ld.d		a5, sp, 8
39	ld.d		a0, sp, 16
40	ld.d		a1, sp, 24
41	ld.d		a2, sp, 32
42	ld.d		a3, sp, 40
43	ld.d		a4, sp, 48
44	addi.d		sp, sp, 64
45
46	jr		ra
47SYM_FUNC_END(arch_bpf_timed_may_goto)
48