linux/arch/powerpc/include/asm/ptrace.h

287 lines
8.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (C) 2001 PPC64 Team, IBM Corp
*
* This struct defines the way the registers are stored on the
* kernel stack during a system call or other kernel entry.
*
* this should only contain volatile regs
* since we can keep non-volatile in the thread_struct
* should set this up when only volatiles are saved
* by intr code.
*
* Since this is going on the stack, *CARE MUST BE TAKEN* to insure
* that the overall structure is a multiple of 16 bytes in length.
*
* Note that the offsets of the fields in this struct correspond with
* the PT_* values below. This simplifies arch/powerpc/kernel/ptrace.c.
*/
#ifndef _ASM_POWERPC_PTRACE_H
#define _ASM_POWERPC_PTRACE_H
#include <uapi/asm/ptrace.h>
#include <asm/asm-const.h>
#ifndef __ASSEMBLY__
struct pt_regs
{
union {
struct user_pt_regs user_regs;
struct {
unsigned long gpr[32];
unsigned long nip;
unsigned long msr;
unsigned long orig_gpr3;
unsigned long ctr;
unsigned long link;
unsigned long xer;
unsigned long ccr;
#ifdef CONFIG_PPC64
unsigned long softe;
#else
unsigned long mq;
#endif
unsigned long trap;
unsigned long dar;
unsigned long dsisr;
unsigned long result;
};
};
union {
struct {
#ifdef CONFIG_PPC64
unsigned long ppr;
#endif
#ifdef CONFIG_PPC_KUAP
unsigned long kuap;
#endif
};
unsigned long __pad[2]; /* Maintain 16 byte interrupt stack alignment */
};
};
#endif
#ifdef __powerpc64__
/*
* Size of redzone that userspace is allowed to use below the stack
* pointer. This is 288 in the 64-bit big-endian ELF ABI, and 512 in
* the new ELFv2 little-endian ABI, so we allow the larger amount.
*
* For kernel code we allow a 288-byte redzone, in order to conserve
* kernel stack space; gcc currently only uses 288 bytes, and will
* hopefully allow explicit control of the redzone size in future.
*/
#define USER_REDZONE_SIZE 512
#define KERNEL_REDZONE_SIZE 288
#define STACK_FRAME_OVERHEAD 112 /* size of minimum stack frame */
#define STACK_FRAME_LR_SAVE 2 /* Location of LR in stack frame */
#define STACK_FRAME_REGS_MARKER ASM_CONST(0x7265677368657265)
#define STACK_INT_FRAME_SIZE (sizeof(struct pt_regs) + \
STACK_FRAME_OVERHEAD + KERNEL_REDZONE_SIZE)
#define STACK_FRAME_MARKER 12
#ifdef PPC64_ELF_ABI_v2
#define STACK_FRAME_MIN_SIZE 32
#else
#define STACK_FRAME_MIN_SIZE STACK_FRAME_OVERHEAD
#endif
/* Size of dummy stack frame allocated when calling signal handler. */
#define __SIGNAL_FRAMESIZE 128
#define __SIGNAL_FRAMESIZE32 64
#else /* __powerpc64__ */
#define USER_REDZONE_SIZE 0
#define KERNEL_REDZONE_SIZE 0
#define STACK_FRAME_OVERHEAD 16 /* size of minimum stack frame */
#define STACK_FRAME_LR_SAVE 1 /* Location of LR in stack frame */
#define STACK_FRAME_REGS_MARKER ASM_CONST(0x72656773)
#define STACK_INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
#define STACK_FRAME_MARKER 2
#define STACK_FRAME_MIN_SIZE STACK_FRAME_OVERHEAD
/* Size of stack frame allocated when calling signal handler. */
#define __SIGNAL_FRAMESIZE 64
#endif /* __powerpc64__ */
#ifndef __ASSEMBLY__
static inline unsigned long instruction_pointer(struct pt_regs *regs)
{
return regs->nip;
}
static inline void instruction_pointer_set(struct pt_regs *regs,
unsigned long val)
{
regs->nip = val;
}
static inline unsigned long user_stack_pointer(struct pt_regs *regs)
{
return regs->gpr[1];
}
static inline unsigned long frame_pointer(struct pt_regs *regs)
{
return 0;
}
#ifdef CONFIG_SMP
extern unsigned long profile_pc(struct pt_regs *regs);
#else
#define profile_pc(regs) instruction_pointer(regs)
#endif
#define kernel_stack_pointer(regs) ((regs)->gpr[1])
static inline int is_syscall_success(struct pt_regs *regs)
{
return !(regs->ccr & 0x10000000);
}
static inline long regs_return_value(struct pt_regs *regs)
{
if (is_syscall_success(regs))
return regs->gpr[3];
else
return -regs->gpr[3];
}
static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)
{
regs->gpr[3] = rc;
}
#ifdef __powerpc64__
#define user_mode(regs) ((((regs)->msr) >> MSR_PR_LG) & 0x1)
#else
#define user_mode(regs) (((regs)->msr & MSR_PR) != 0)
#endif
#define force_successful_syscall_return() \
do { \
set_thread_flag(TIF_NOERROR); \
} while(0)
struct task_struct;
extern int ptrace_get_reg(struct task_struct *task, int regno,
unsigned long *data);
extern int ptrace_put_reg(struct task_struct *task, int regno,
unsigned long data);
#define current_pt_regs() \
((struct pt_regs *)((unsigned long)task_stack_page(current) + THREAD_SIZE) - 1)
/*
* We use the least-significant bit of the trap field to indicate
* whether we have saved the full set of registers, or only a
* partial set. A 1 there means the partial set.
* On 4xx we use the next bit to indicate whether the exception
* is a critical exception (1 means it is).
*/
#define FULL_REGS(regs) (((regs)->trap & 1) == 0)
#ifndef __powerpc64__
#define IS_CRITICAL_EXC(regs) (((regs)->trap & 2) != 0)
#define IS_MCHECK_EXC(regs) (((regs)->trap & 4) != 0)
#define IS_DEBUG_EXC(regs) (((regs)->trap & 8) != 0)
#endif /* ! __powerpc64__ */
#define TRAP(regs) ((regs)->trap & ~0xF)
#ifdef __powerpc64__
#define NV_REG_POISON 0xdeadbeefdeadbeefUL
#define CHECK_FULL_REGS(regs) BUG_ON(regs->trap & 1)
#else
#define NV_REG_POISON 0xdeadbeef
#define CHECK_FULL_REGS(regs) \
do { \
if ((regs)->trap & 1) \
printk(KERN_CRIT "%s: partial register set\n", __func__); \
} while (0)
#endif /* __powerpc64__ */
#define arch_has_single_step() (1)
#ifndef CONFIG_BOOK3S_601
#define arch_has_block_step() (true)
#else
#define arch_has_block_step() (false)
#endif
#define ARCH_HAS_USER_SINGLE_STEP_REPORT
/*
* kprobe-based event tracer support
*/
#include <linux/stddef.h>
#include <linux/thread_info.h>
extern int regs_query_register_offset(const char *name);
extern const char *regs_query_register_name(unsigned int offset);
#define MAX_REG_OFFSET (offsetof(struct pt_regs, dsisr))
/**
* regs_get_register() - get register value from its offset
* @regs: pt_regs from which register value is gotten
* @offset: offset number 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 unsigned long regs_get_register(struct pt_regs *regs,
unsigned int offset)
{
if (unlikely(offset > MAX_REG_OFFSET))
return 0;
return *(unsigned long *)((unsigned long)regs + offset);
}
/**
* regs_within_kernel_stack() - check the address in the stack
* @regs: pt_regs which contains kernel stack pointer.
* @addr: address which is checked.
*
* regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
* If @addr is within the kernel stack, it returns true. If not, returns false.
*/
static inline bool regs_within_kernel_stack(struct pt_regs *regs,
unsigned long addr)
{
return ((addr & ~(THREAD_SIZE - 1)) ==
(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
}
/**
* regs_get_kernel_stack_nth() - get Nth entry of the stack
* @regs: pt_regs which contains kernel stack pointer.
* @n: stack entry number.
*
* regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
* is specified by @regs. If the @n th entry is NOT in the kernel stack,
* this returns 0.
*/
static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
unsigned int n)
{
unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
addr += n;
if (regs_within_kernel_stack(regs, (unsigned long)addr))
return *addr;
else
return 0;
}
#endif /* __ASSEMBLY__ */
#ifndef __powerpc64__
#else /* __powerpc64__ */
#define PT_FPSCR32 (PT_FPR0 + 2*32 + 1) /* each FP reg occupies 2 32-bit userspace slots */
#define PT_VR0_32 164 /* each Vector reg occupies 4 slots in 32-bit */
#define PT_VSCR_32 (PT_VR0 + 32*4 + 3)
#define PT_VRSAVE_32 (PT_VR0 + 33*4)
#define PT_VSR0_32 300 /* each VSR reg occupies 4 slots in 32-bit */
#endif /* __powerpc64__ */
#endif /* _ASM_POWERPC_PTRACE_H */