text: /*
   * 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.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version
   * 2 of the License, or (at your option) any later version.
   */
  #ifndef _ASM_POWERPC_PTRACE_H
  #define _ASM_POWERPC_PTRACE_H
  
  #include <uapi/asm/ptrace.h>
  #include <asm/asm-const.h>
  
  
  #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__
  
  #define GET_IP(regs)		((regs)->nip)
  #define GET_USP(regs)		((regs)->gpr[1])
  #define GET_FP(regs)		(0)
  #define SET_FP(regs, val)
  
  #ifdef CONFIG_SMP
  extern unsigned long profile_pc(struct pt_regs *regs);
  #define profile_pc profile_pc
  #endif
  
  #include <asm-generic/ptrace.h>
  
  #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];
  }
  
  #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)current_thread_info() + 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)
  #define arch_has_block_step()	(!cpu_has_feature(CPU_FTR_601))
  #define ARCH_HAS_USER_SINGLE_STEP_INFO
  
  /*
   * 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 */
  