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Diffstat (limited to 'arch/arm64/include/asm/ptrace.h')
| -rw-r--r-- | arch/arm64/include/asm/ptrace.h | 389 |
1 files changed, 389 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h new file mode 100644 index 000000000..d3106f5e1 --- /dev/null +++ b/arch/arm64/include/asm/ptrace.h @@ -0,0 +1,389 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Based on arch/arm/include/asm/ptrace.h + * + * Copyright (C) 1996-2003 Russell King + * Copyright (C) 2012 ARM Ltd. + */ +#ifndef __ASM_PTRACE_H +#define __ASM_PTRACE_H + +#include <asm/cpufeature.h> + +#include <uapi/asm/ptrace.h> + +/* Current Exception Level values, as contained in CurrentEL */ +#define CurrentEL_EL1 (1 << 2) +#define CurrentEL_EL2 (2 << 2) + +/* + * PMR values used to mask/unmask interrupts. + * + * GIC priority masking works as follows: if an IRQ's priority is a higher value + * than the value held in PMR, that IRQ is masked. Lowering the value of PMR + * means masking more IRQs (or at least that the same IRQs remain masked). + * + * To mask interrupts, we clear the most significant bit of PMR. + * + * Some code sections either automatically switch back to PSR.I or explicitly + * require to not use priority masking. If bit GIC_PRIO_PSR_I_SET is included + * in the priority mask, it indicates that PSR.I should be set and + * interrupt disabling temporarily does not rely on IRQ priorities. + */ +#define GIC_PRIO_IRQON 0xe0 +#define __GIC_PRIO_IRQOFF (GIC_PRIO_IRQON & ~0x80) +#define __GIC_PRIO_IRQOFF_NS 0xa0 +#define GIC_PRIO_PSR_I_SET (1 << 4) + +#define GIC_PRIO_IRQOFF \ + ({ \ + extern struct static_key_false gic_nonsecure_priorities;\ + u8 __prio = __GIC_PRIO_IRQOFF; \ + \ + if (static_branch_unlikely(&gic_nonsecure_priorities)) \ + __prio = __GIC_PRIO_IRQOFF_NS; \ + \ + __prio; \ + }) + +/* Additional SPSR bits not exposed in the UABI */ +#define PSR_MODE_THREAD_BIT (1 << 0) +#define PSR_IL_BIT (1 << 20) + +/* AArch32-specific ptrace requests */ +#define COMPAT_PTRACE_GETREGS 12 +#define COMPAT_PTRACE_SETREGS 13 +#define COMPAT_PTRACE_GET_THREAD_AREA 22 +#define COMPAT_PTRACE_SET_SYSCALL 23 +#define COMPAT_PTRACE_GETVFPREGS 27 +#define COMPAT_PTRACE_SETVFPREGS 28 +#define COMPAT_PTRACE_GETHBPREGS 29 +#define COMPAT_PTRACE_SETHBPREGS 30 + +/* SPSR_ELx bits for exceptions taken from AArch32 */ +#define PSR_AA32_MODE_MASK 0x0000001f +#define PSR_AA32_MODE_USR 0x00000010 +#define PSR_AA32_MODE_FIQ 0x00000011 +#define PSR_AA32_MODE_IRQ 0x00000012 +#define PSR_AA32_MODE_SVC 0x00000013 +#define PSR_AA32_MODE_ABT 0x00000017 +#define PSR_AA32_MODE_HYP 0x0000001a +#define PSR_AA32_MODE_UND 0x0000001b +#define PSR_AA32_MODE_SYS 0x0000001f +#define PSR_AA32_T_BIT 0x00000020 +#define PSR_AA32_F_BIT 0x00000040 +#define PSR_AA32_I_BIT 0x00000080 +#define PSR_AA32_A_BIT 0x00000100 +#define PSR_AA32_E_BIT 0x00000200 +#define PSR_AA32_PAN_BIT 0x00400000 +#define PSR_AA32_SSBS_BIT 0x00800000 +#define PSR_AA32_DIT_BIT 0x01000000 +#define PSR_AA32_Q_BIT 0x08000000 +#define PSR_AA32_V_BIT 0x10000000 +#define PSR_AA32_C_BIT 0x20000000 +#define PSR_AA32_Z_BIT 0x40000000 +#define PSR_AA32_N_BIT 0x80000000 +#define PSR_AA32_IT_MASK 0x0600fc00 /* If-Then execution state mask */ +#define PSR_AA32_GE_MASK 0x000f0000 + +#ifdef CONFIG_CPU_BIG_ENDIAN +#define PSR_AA32_ENDSTATE PSR_AA32_E_BIT +#else +#define PSR_AA32_ENDSTATE 0 +#endif + +/* AArch32 CPSR bits, as seen in AArch32 */ +#define COMPAT_PSR_DIT_BIT 0x00200000 + +/* + * These are 'magic' values for PTRACE_PEEKUSR that return info about where a + * process is located in memory. + */ +#define COMPAT_PT_TEXT_ADDR 0x10000 +#define COMPAT_PT_DATA_ADDR 0x10004 +#define COMPAT_PT_TEXT_END_ADDR 0x10008 + +/* + * If pt_regs.syscallno == NO_SYSCALL, then the thread is not executing + * a syscall -- i.e., its most recent entry into the kernel from + * userspace was not via SVC, or otherwise a tracer cancelled the syscall. + * + * This must have the value -1, for ABI compatibility with ptrace etc. + */ +#define NO_SYSCALL (-1) + +#ifndef __ASSEMBLY__ +#include <linux/bug.h> +#include <linux/types.h> + +/* sizeof(struct user) for AArch32 */ +#define COMPAT_USER_SZ 296 + +/* Architecturally defined mapping between AArch32 and AArch64 registers */ +#define compat_usr(x) regs[(x)] +#define compat_fp regs[11] +#define compat_sp regs[13] +#define compat_lr regs[14] +#define compat_sp_hyp regs[15] +#define compat_lr_irq regs[16] +#define compat_sp_irq regs[17] +#define compat_lr_svc regs[18] +#define compat_sp_svc regs[19] +#define compat_lr_abt regs[20] +#define compat_sp_abt regs[21] +#define compat_lr_und regs[22] +#define compat_sp_und regs[23] +#define compat_r8_fiq regs[24] +#define compat_r9_fiq regs[25] +#define compat_r10_fiq regs[26] +#define compat_r11_fiq regs[27] +#define compat_r12_fiq regs[28] +#define compat_sp_fiq regs[29] +#define compat_lr_fiq regs[30] + +static inline unsigned long compat_psr_to_pstate(const unsigned long psr) +{ + unsigned long pstate; + + pstate = psr & ~COMPAT_PSR_DIT_BIT; + + if (psr & COMPAT_PSR_DIT_BIT) + pstate |= PSR_AA32_DIT_BIT; + + return pstate; +} + +static inline unsigned long pstate_to_compat_psr(const unsigned long pstate) +{ + unsigned long psr; + + psr = pstate & ~PSR_AA32_DIT_BIT; + + if (pstate & PSR_AA32_DIT_BIT) + psr |= COMPAT_PSR_DIT_BIT; + + return psr; +} + +/* + * This struct defines the way the registers are stored on the stack during an + * exception. Note that sizeof(struct pt_regs) has to be a multiple of 16 (for + * stack alignment). struct user_pt_regs must form a prefix of struct pt_regs. + */ +struct pt_regs { + union { + struct user_pt_regs user_regs; + struct { + u64 regs[31]; + u64 sp; + u64 pc; + u64 pstate; + }; + }; + u64 orig_x0; +#ifdef __AARCH64EB__ + u32 unused2; + s32 syscallno; +#else + s32 syscallno; + u32 unused2; +#endif + + u64 orig_addr_limit; + /* Only valid when ARM64_HAS_IRQ_PRIO_MASKING is enabled. */ + u64 pmr_save; + u64 stackframe[2]; + + /* Only valid for some EL1 exceptions. */ + u64 lockdep_hardirqs; + u64 exit_rcu; +}; + +static inline bool in_syscall(struct pt_regs const *regs) +{ + return regs->syscallno != NO_SYSCALL; +} + +static inline void forget_syscall(struct pt_regs *regs) +{ + regs->syscallno = NO_SYSCALL; +} + +#define MAX_REG_OFFSET offsetof(struct pt_regs, pstate) + +#define arch_has_single_step() (1) + +#ifdef CONFIG_COMPAT +#define compat_thumb_mode(regs) \ + (((regs)->pstate & PSR_AA32_T_BIT)) +#else +#define compat_thumb_mode(regs) (0) +#endif + +#define user_mode(regs) \ + (((regs)->pstate & PSR_MODE_MASK) == PSR_MODE_EL0t) + +#define compat_user_mode(regs) \ + (((regs)->pstate & (PSR_MODE32_BIT | PSR_MODE_MASK)) == \ + (PSR_MODE32_BIT | PSR_MODE_EL0t)) + +#define processor_mode(regs) \ + ((regs)->pstate & PSR_MODE_MASK) + +#define irqs_priority_unmasked(regs) \ + (system_uses_irq_prio_masking() ? \ + (regs)->pmr_save == GIC_PRIO_IRQON : \ + true) + +#define interrupts_enabled(regs) \ + (!((regs)->pstate & PSR_I_BIT) && irqs_priority_unmasked(regs)) + +#define fast_interrupts_enabled(regs) \ + (!((regs)->pstate & PSR_F_BIT)) + +static inline unsigned long user_stack_pointer(struct pt_regs *regs) +{ + if (compat_user_mode(regs)) + return regs->compat_sp; + return regs->sp; +} + +extern int regs_query_register_offset(const char *name); +extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, + unsigned int n); + +/** + * regs_get_register() - get register value from its offset + * @regs: pt_regs from which register value is gotten + * @offset: offset of the register. + * + * regs_get_register returns the value of a register whose offset from @regs. + * The @offset is the offset of the register in struct pt_regs. + * If @offset is bigger than MAX_REG_OFFSET, this returns 0. + */ +static inline u64 regs_get_register(struct pt_regs *regs, unsigned int offset) +{ + u64 val = 0; + + WARN_ON(offset & 7); + + offset >>= 3; + switch (offset) { + case 0 ... 30: + val = regs->regs[offset]; + break; + case offsetof(struct pt_regs, sp) >> 3: + val = regs->sp; + break; + case offsetof(struct pt_regs, pc) >> 3: + val = regs->pc; + break; + case offsetof(struct pt_regs, pstate) >> 3: + val = regs->pstate; + break; + default: + val = 0; + } + + return val; +} + +/* + * Read a register given an architectural register index r. + * This handles the common case where 31 means XZR, not SP. + */ +static inline unsigned long pt_regs_read_reg(const struct pt_regs *regs, int r) +{ + return (r == 31) ? 0 : regs->regs[r]; +} + +/* + * Write a register given an architectural register index r. + * This handles the common case where 31 means XZR, not SP. + */ +static inline void pt_regs_write_reg(struct pt_regs *regs, int r, + unsigned long val) +{ + if (r != 31) + regs->regs[r] = val; +} + +/* Valid only for Kernel mode traps. */ +static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) +{ + return regs->sp; +} + +static inline unsigned long regs_return_value(struct pt_regs *regs) +{ + unsigned long val = regs->regs[0]; + + /* + * Audit currently uses regs_return_value() instead of + * syscall_get_return_value(). Apply the same sign-extension here until + * audit is updated to use syscall_get_return_value(). + */ + if (compat_user_mode(regs)) + val = sign_extend64(val, 31); + + return val; +} + +static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) +{ + regs->regs[0] = rc; +} + +/** + * regs_get_kernel_argument() - get Nth function argument in kernel + * @regs: pt_regs of that context + * @n: function argument number (start from 0) + * + * regs_get_argument() returns @n th argument of the function call. + * + * Note that this chooses the most likely register mapping. In very rare + * cases this may not return correct data, for example, if one of the + * function parameters is 16 bytes or bigger. In such cases, we cannot + * get access the parameter correctly and the register assignment of + * subsequent parameters will be shifted. + */ +static inline unsigned long regs_get_kernel_argument(struct pt_regs *regs, + unsigned int n) +{ +#define NR_REG_ARGUMENTS 8 + if (n < NR_REG_ARGUMENTS) + return pt_regs_read_reg(regs, n); + return 0; +} + +/* We must avoid circular header include via sched.h */ +struct task_struct; +int valid_user_regs(struct user_pt_regs *regs, struct task_struct *task); + +static inline unsigned long instruction_pointer(struct pt_regs *regs) +{ + return regs->pc; +} +static inline void instruction_pointer_set(struct pt_regs *regs, + unsigned long val) +{ + regs->pc = val; +} + +static inline unsigned long frame_pointer(struct pt_regs *regs) +{ + return regs->regs[29]; +} + +#define procedure_link_pointer(regs) ((regs)->regs[30]) + +static inline void procedure_link_pointer_set(struct pt_regs *regs, + unsigned long val) +{ + procedure_link_pointer(regs) = val; +} + +extern unsigned long profile_pc(struct pt_regs *regs); + +#endif /* __ASSEMBLY__ */ +#endif |