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