1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * trampoline entry and return code for kretprobes.
4 */
5
6#include <linux/linkage.h>
7#include <asm/asm-offsets.h>
8#include <asm/assembler.h>
9
10	.text
11
12	.macro	save_all_base_regs
13	stp x0, x1, [sp, #S_X0]
14	stp x2, x3, [sp, #S_X2]
15	stp x4, x5, [sp, #S_X4]
16	stp x6, x7, [sp, #S_X6]
17	stp x8, x9, [sp, #S_X8]
18	stp x10, x11, [sp, #S_X10]
19	stp x12, x13, [sp, #S_X12]
20	stp x14, x15, [sp, #S_X14]
21	stp x16, x17, [sp, #S_X16]
22	stp x18, x19, [sp, #S_X18]
23	stp x20, x21, [sp, #S_X20]
24	stp x22, x23, [sp, #S_X22]
25	stp x24, x25, [sp, #S_X24]
26	stp x26, x27, [sp, #S_X26]
27	stp x28, x29, [sp, #S_X28]
28	add x0, sp, #PT_REGS_SIZE
29	stp lr, x0, [sp, #S_LR]
30	/*
31	 * Construct a useful saved PSTATE
32	 */
33	mrs x0, nzcv
34	mrs x1, daif
35	orr x0, x0, x1
36	mrs x1, CurrentEL
37	orr x0, x0, x1
38	mrs x1, SPSel
39	orr x0, x0, x1
40	stp xzr, x0, [sp, #S_PC]
41	.endm
42
43	.macro	restore_all_base_regs
44	ldr x0, [sp, #S_PSTATE]
45	and x0, x0, #(PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT)
46	msr nzcv, x0
47	ldp x0, x1, [sp, #S_X0]
48	ldp x2, x3, [sp, #S_X2]
49	ldp x4, x5, [sp, #S_X4]
50	ldp x6, x7, [sp, #S_X6]
51	ldp x8, x9, [sp, #S_X8]
52	ldp x10, x11, [sp, #S_X10]
53	ldp x12, x13, [sp, #S_X12]
54	ldp x14, x15, [sp, #S_X14]
55	ldp x16, x17, [sp, #S_X16]
56	ldp x18, x19, [sp, #S_X18]
57	ldp x20, x21, [sp, #S_X20]
58	ldp x22, x23, [sp, #S_X22]
59	ldp x24, x25, [sp, #S_X24]
60	ldp x26, x27, [sp, #S_X26]
61	ldp x28, x29, [sp, #S_X28]
62	.endm
63
64SYM_CODE_START(__kretprobe_trampoline)
65	sub sp, sp, #PT_REGS_SIZE
66
67	save_all_base_regs
68
69	/* Setup a frame pointer. */
70	add x29, sp, #S_FP
71
72	mov x0, sp
73	bl trampoline_probe_handler
74	/*
75	 * Replace trampoline address in lr with actual orig_ret_addr return
76	 * address.
77	 */
78	mov lr, x0
79
80	/* The frame pointer (x29) is restored with other registers. */
81	restore_all_base_regs
82
83	add sp, sp, #PT_REGS_SIZE
84	ret
85
86SYM_CODE_END(__kretprobe_trampoline)
87