/* 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 <linux/err.h>
#include <uapi/asm/ptrace.h>
#include <asm/asm-const.h>
#include <asm/reg.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;
union {
unsigned long dar;
unsigned long dear;
};
union {
unsigned long dsisr;
unsigned long esr;
};
unsigned long result;
};
};
#if defined(CONFIG_PPC64) || defined(CONFIG_PPC_KUAP)
union {
struct {
#ifdef CONFIG_PPC64
unsigned long ppr;
unsigned long exit_result;
#endif
union {
#ifdef CONFIG_PPC_KUAP
unsigned long kuap;
#endif
#ifdef CONFIG_PPC_PKEY
unsigned long amr;
#endif
};
#ifdef CONFIG_PPC_PKEY
unsigned long iamr;
#endif
};
unsigned long __pad[4]; /* Maintain 16 byte interrupt stack alignment */
};
#endif
#if defined(CONFIG_PPC32) && defined(CONFIG_BOOKE)
struct { /* Must be a multiple of 16 bytes */
unsigned long mas0;
unsigned long mas1;
unsigned long mas2;
unsigned long mas3;
unsigned long mas6;
unsigned long mas7;
unsigned long srr0;
unsigned long srr1;
unsigned long csrr0;
unsigned long csrr1;
unsigned long dsrr0;
unsigned long dsrr1;
};
#endif
};
#endif
// Always displays as "REGS" in memory dumps
#ifdef CONFIG_CPU_BIG_ENDIAN
#define STACK_FRAME_REGS_MARKER ASM_CONST(0x52454753)
#else
#define STACK_FRAME_REGS_MARKER ASM_CONST(0x53474552)
#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_LR_SAVE 2 /* Location of LR in stack frame */
#ifdef CONFIG_PPC64_ELF_ABI_V2
#define STACK_FRAME_MIN_SIZE 32
#define STACK_USER_INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_MIN_SIZE + 16)
#define STACK_INT_FRAME_REGS (STACK_FRAME_MIN_SIZE + 16)
#define STACK_INT_FRAME_MARKER STACK_FRAME_MIN_SIZE
#define STACK_SWITCH_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_MIN_SIZE + 16)
#define STACK_SWITCH_FRAME_REGS (STACK_FRAME_MIN_SIZE + 16)
#else
/*
* The ELFv1 ABI specifies 48 bytes plus a minimum 64 byte parameter save
* area. This parameter area is not used by calls to C from interrupt entry,
* so the second from last one of those is used for the frame marker.
*/
#define STACK_FRAME_MIN_SIZE 112
#define STACK_USER_INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_MIN_SIZE)
#define STACK_INT_FRAME_REGS STACK_FRAME_MIN_SIZE
#define STACK_INT_FRAME_MARKER (STACK_FRAME_MIN_SIZE - 16)
#define STACK_SWITCH_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_MIN_SIZE)
#define STACK_SWITCH_FRAME_REGS STACK_FRAME_MIN_SIZE
#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_MIN_SIZE 16
#define STACK_FRAME_LR_SAVE 1 /* Location of LR in stack frame */
#define STACK_USER_INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_MIN_SIZE)
#define STACK_INT_FRAME_REGS STACK_FRAME_MIN_SIZE
#define STACK_INT_FRAME_MARKER (STACK_FRAME_MIN_SIZE - 8)
#define STACK_SWITCH_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_MIN_SIZE)
#define STACK_SWITCH_FRAME_REGS STACK_FRAME_MIN_SIZE
/* Size of stack frame allocated when calling signal handler. */
#define __SIGNAL_FRAMESIZE 64
#endif /* __powerpc64__ */
#define STACK_INT_FRAME_SIZE (KERNEL_REDZONE_SIZE + STACK_USER_INT_FRAME_SIZE)
#define STACK_INT_FRAME_MARKER_LONGS (STACK_INT_FRAME_MARKER/sizeof(long))
#ifndef __ASSEMBLY__
#include <asm/paca.h>
#ifdef CONFIG_SMP
extern unsigned long profile_pc(struct pt_regs *regs);
#else
#define profile_pc(regs) instruction_pointer(regs)
#endif
long do_syscall_trace_enter(struct pt_regs *regs);
void do_syscall_trace_leave(struct pt_regs *regs);
static inline void set_return_regs_changed(void)
{
#ifdef CONFIG_PPC_BOOK3S_64
WRITE_ONCE(local_paca->hsrr_valid, 0);
WRITE_ONCE(local_paca->srr_valid, 0);
#endif
}
static inline void regs_set_return_ip(struct pt_regs *regs, unsigned long ip)
{
regs->nip = ip;
set_return_regs_changed();
}
static inline void regs_set_return_msr(struct pt_regs *regs, unsigned long msr)
{
regs->msr = msr;
set_return_regs_changed();
}
static inline void regs_add_return_ip(struct pt_regs *regs, long offset)
{
regs_set_return_ip(regs, regs->nip + offset);
}
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_set_return_ip(regs, 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;
}
#define user_mode(regs) (((regs)->msr & MSR_PR) != 0)
#define force_successful_syscall_return() \
do { \
set_thread_flag(TIF_NOERROR); \
} while(0)
#define current_pt_regs() \
((struct pt_regs *)((unsigned long)task_stack_page(current) + THREAD_SIZE) - 1)
/*
* The 4 low bits (0xf) are available as flags to overload the trap word,
* because interrupt vectors have minimum alignment of 0x10. TRAP_FLAGS_MASK
* must cover the bits used as flags, including bit 0 which is used as the
* "norestart" bit.
*/
#ifdef __powerpc64__
#define TRAP_FLAGS_MASK 0x1
#else
/*
* On 4xx we use bit 1 in the trap word to indicate whether the exception
* is a critical exception (1 means it is).
*/
#define TRAP_FLAGS_MASK 0xf
#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 & ~TRAP_FLAGS_MASK)
static __always_inline void set_trap(struct pt_regs *regs, unsigned long val)
{
regs->trap = (regs->trap & TRAP_FLAGS_MASK) | (val & ~TRAP_FLAGS_MASK);
}
static inline bool trap_is_scv(struct pt_regs *regs)
{
return (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && TRAP(regs) == 0x3000);
}
static inline bool trap_is_unsupported_scv(struct pt_regs *regs)
{
return IS_ENABLED(CONFIG_PPC_BOOK3S_64) && TRAP(regs) == 0x7ff0;
}
static inline bool trap_is_syscall(struct pt_regs *regs)
{
return (trap_is_scv(regs) || TRAP(regs) == 0xc00);
}
static inline bool trap_norestart(struct pt_regs *regs)
{
return regs->trap & 0x1;
}
static __always_inline void set_trap_norestart(struct pt_regs *regs)
{
regs->trap |= 0x1;
}
#define kernel_stack_pointer(regs) ((regs)->gpr[1])
static inline int is_syscall_success(struct pt_regs *regs)
{
if (trap_is_scv(regs))
return !IS_ERR_VALUE((unsigned long)regs->gpr[3]);
else
return !(regs->ccr & 0x10000000);
}
static inline long regs_return_value(struct pt_regs *regs)
{
if (trap_is_scv(regs))
return regs->gpr[3];
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;
}
static inline bool cpu_has_msr_ri(void)
{
return !IS_ENABLED(CONFIG_BOOKE);
}
static inline bool regs_is_unrecoverable(struct pt_regs *regs)
{
return unlikely(cpu_has_msr_ri() && !(regs->msr & MSR_RI));
}
static inline void regs_set_recoverable(struct pt_regs *regs)
{
if (cpu_has_msr_ri())
regs_set_return_msr(regs, regs->msr | MSR_RI);
}
static inline void regs_set_unrecoverable(struct pt_regs *regs)
{
if (cpu_has_msr_ri())
regs_set_return_msr(regs, regs->msr & ~MSR_RI);
}
#define arch_has_single_step() (1)
#define arch_has_block_step() (true)
#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;
}
/**
* regs_get_kernel_argument() - get Nth function argument in kernel
* @regs: pt_regs of that context
* @n: function argument number (start from 0)
*
* We support up to 8 arguments and assume they are sent in through the GPRs.
* This will fail for fp/vector arguments, but those aren't usually found in
* kernel code. This is expected to be called from kprobes or ftrace with regs.
*/
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 regs_get_register(regs, offsetof(struct pt_regs, gpr[3 + n]));
return 0;
}
#endif /* __ASSEMBLY__ */
#ifndef __powerpc64__
/* We need PT_SOFTE defined at all time to avoid #ifdefs */
#define PT_SOFTE PT_MQ
#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 */
Codebase Browser
linux