1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* |
3 | * Macros for Flexible Return and Event Delivery (FRED) |
4 | */ |
5 | |
6 | #ifndef ASM_X86_FRED_H |
7 | #define ASM_X86_FRED_H |
8 | |
9 | #include <linux/const.h> |
10 | |
11 | #include <asm/asm.h> |
12 | #include <asm/trapnr.h> |
13 | |
14 | /* |
15 | * FRED event return instruction opcodes for ERET{S,U}; supported in |
16 | * binutils >= 2.41. |
17 | */ |
18 | #define ERETS _ASM_BYTES(0xf2,0x0f,0x01,0xca) |
19 | #define ERETU _ASM_BYTES(0xf3,0x0f,0x01,0xca) |
20 | |
21 | /* |
22 | * RSP is aligned to a 64-byte boundary before used to push a new stack frame |
23 | */ |
24 | #define FRED_STACK_FRAME_RSP_MASK _AT(unsigned long, (~0x3f)) |
25 | |
26 | /* |
27 | * Used for the return address for call emulation during code patching, |
28 | * and measured in 64-byte cache lines. |
29 | */ |
30 | #define FRED_CONFIG_REDZONE_AMOUNT 1 |
31 | #define FRED_CONFIG_REDZONE (_AT(unsigned long, FRED_CONFIG_REDZONE_AMOUNT) << 6) |
32 | #define FRED_CONFIG_INT_STKLVL(l) (_AT(unsigned long, l) << 9) |
33 | #define FRED_CONFIG_ENTRYPOINT(p) _AT(unsigned long, (p)) |
34 | |
35 | #ifndef __ASSEMBLY__ |
36 | |
37 | #ifdef CONFIG_X86_FRED |
38 | #include <linux/kernel.h> |
39 | |
40 | #include <asm/ptrace.h> |
41 | |
42 | struct fred_info { |
43 | /* Event data: CR2, DR6, ... */ |
44 | unsigned long edata; |
45 | unsigned long resv; |
46 | }; |
47 | |
48 | /* Full format of the FRED stack frame */ |
49 | struct fred_frame { |
50 | struct pt_regs regs; |
51 | struct fred_info info; |
52 | }; |
53 | |
54 | static __always_inline struct fred_info *fred_info(struct pt_regs *regs) |
55 | { |
56 | return &container_of(regs, struct fred_frame, regs)->info; |
57 | } |
58 | |
59 | static __always_inline unsigned long fred_event_data(struct pt_regs *regs) |
60 | { |
61 | return fred_info(regs)->edata; |
62 | } |
63 | |
64 | void asm_fred_entrypoint_user(void); |
65 | void asm_fred_entrypoint_kernel(void); |
66 | void asm_fred_entry_from_kvm(struct fred_ss); |
67 | |
68 | __visible void fred_entry_from_user(struct pt_regs *regs); |
69 | __visible void fred_entry_from_kernel(struct pt_regs *regs); |
70 | __visible void __fred_entry_from_kvm(struct pt_regs *regs); |
71 | |
72 | /* Can be called from noinstr code, thus __always_inline */ |
73 | static __always_inline void fred_entry_from_kvm(unsigned int type, unsigned int vector) |
74 | { |
75 | struct fred_ss ss = { |
76 | .ss =__KERNEL_DS, |
77 | .type = type, |
78 | .vector = vector, |
79 | .nmi = type == EVENT_TYPE_NMI, |
80 | .lm = 1, |
81 | }; |
82 | |
83 | asm_fred_entry_from_kvm(ss); |
84 | } |
85 | |
86 | void cpu_init_fred_exceptions(void); |
87 | void fred_complete_exception_setup(void); |
88 | |
89 | #else /* CONFIG_X86_FRED */ |
90 | static __always_inline unsigned long fred_event_data(struct pt_regs *regs) { return 0; } |
91 | static inline void cpu_init_fred_exceptions(void) { } |
92 | static inline void fred_complete_exception_setup(void) { } |
93 | static __always_inline void fred_entry_from_kvm(unsigned int type, unsigned int vector) { } |
94 | #endif /* CONFIG_X86_FRED */ |
95 | #endif /* !__ASSEMBLY__ */ |
96 | |
97 | #endif /* ASM_X86_FRED_H */ |
98 | |