arch/um/sys-i386/ptrace.c - kernel/msm - Gitiles

 /*
  * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
  * Licensed under the GPL
  */

 #include <linux/compiler.h>
 #include "linux/sched.h"
 #include "linux/mm.h"
 #include "asm/elf.h"
 #include "asm/ptrace.h"
 #include "asm/uaccess.h"
 #include "asm/unistd.h"
 #include "sysdep/ptrace.h"
 #include "sysdep/sigcontext.h"
 #include "sysdep/sc.h"

 void arch_switch_to_skas(struct task_struct *from, struct task_struct *to)
 {
 	int err = arch_switch_tls_skas(from, to);
 	if (!err)
 		return;

 	if (err != -EINVAL)
 		printk(KERN_WARNING "arch_switch_tls_skas failed, errno %d, not EINVAL\n", -err);
 	else
 		printk(KERN_WARNING "arch_switch_tls_skas failed, errno = EINVAL\n");
 }

 int is_syscall(unsigned long addr)
 {
 	unsigned short instr;
 	int n;

 	n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
 	if(n){
 		/* access_process_vm() grants access to vsyscall and stub,
 		 * while copy_from_user doesn't. Maybe access_process_vm is
 		 * slow, but that doesn't matter, since it will be called only
 		 * in case of singlestepping, if copy_from_user failed.
 		 */
 		n = access_process_vm(current, addr, &instr, sizeof(instr), 0);
 		if(n != sizeof(instr)) {
 			printk("is_syscall : failed to read instruction from "
 			       "0x%lx\n", addr);
 			return(1);
 		}
 	}
 	/* int 0x80 or sysenter */
 	return((instr == 0x80cd) || (instr == 0x340f));
 }

 /* determines which flags the user has access to. */
 /* 1 = access 0 = no access */
 #define FLAG_MASK 0x00044dd5

 int putreg(struct task_struct *child, int regno, unsigned long value)
 {
 	regno >>= 2;
 	switch (regno) {
 	case FS:
 		if (value && (value & 3) != 3)
 			return -EIO;
 		PT_REGS_FS(&child->thread.regs) = value;
 		return 0;
 	case GS:
 		if (value && (value & 3) != 3)
 			return -EIO;
 		PT_REGS_GS(&child->thread.regs) = value;
 		return 0;
 	case DS:
 	case ES:
 		if (value && (value & 3) != 3)
 			return -EIO;
 		value &= 0xffff;
 		break;
 	case SS:
 	case CS:
 		if ((value & 3) != 3)
 			return -EIO;
 		value &= 0xffff;
 		break;
 	case EFL:
 		value &= FLAG_MASK;
 		value |= PT_REGS_EFLAGS(&child->thread.regs);
 		break;
 	}
 	PT_REGS_SET(&child->thread.regs, regno, value);
 	return 0;
 }

 int poke_user(struct task_struct *child, long addr, long data)
 {
         if ((addr & 3) || addr < 0)
                 return -EIO;

         if (addr < MAX_REG_OFFSET)
                 return putreg(child, addr, data);

         else if((addr >= offsetof(struct user, u_debugreg[0])) &&
                 (addr <= offsetof(struct user, u_debugreg[7]))){
                 addr -= offsetof(struct user, u_debugreg[0]);
                 addr = addr >> 2;
                 if((addr == 4) || (addr == 5)) return -EIO;
                 child->thread.arch.debugregs[addr] = data;
                 return 0;
         }
         return -EIO;
 }

 unsigned long getreg(struct task_struct *child, int regno)
 {
 	unsigned long retval = ~0UL;

 	regno >>= 2;
 	switch (regno) {
 	case FS:
 	case GS:
 	case DS:
 	case ES:
 	case SS:
 	case CS:
 		retval = 0xffff;
 		/* fall through */
 	default:
 		retval &= PT_REG(&child->thread.regs, regno);
 	}
 	return retval;
 }

 int peek_user(struct task_struct *child, long addr, long data)
 {
 /* read the word at location addr in the USER area. */
 	unsigned long tmp;

 	if ((addr & 3) || addr < 0)
 		return -EIO;

 	tmp = 0;  /* Default return condition */
 	if(addr < MAX_REG_OFFSET){
 		tmp = getreg(child, addr);
 	}
 	else if((addr >= offsetof(struct user, u_debugreg[0])) &&
 		(addr <= offsetof(struct user, u_debugreg[7]))){
 		addr -= offsetof(struct user, u_debugreg[0]);
 		addr = addr >> 2;
 		tmp = child->thread.arch.debugregs[addr];
 	}
 	return put_user(tmp, (unsigned long __user *) data);
 }

 struct i387_fxsave_struct {
 	unsigned short	cwd;
 	unsigned short	swd;
 	unsigned short	twd;
 	unsigned short	fop;
 	long	fip;
 	long	fcs;
 	long	foo;
 	long	fos;
 	long	mxcsr;
 	long	reserved;
 	long	st_space[32];	/* 8*16 bytes for each FP-reg = 128 bytes */
 	long	xmm_space[32];	/* 8*16 bytes for each XMM-reg = 128 bytes */
 	long	padding[56];
 };

 /*
  * FPU tag word conversions.
  */

 static inline unsigned short twd_i387_to_fxsr( unsigned short twd )
 {
 	unsigned int tmp; /* to avoid 16 bit prefixes in the code */

 	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
         tmp = ~twd;
         tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
         /* and move the valid bits to the lower byte. */
         tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
         tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
         tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
         return tmp;
 }

 static inline unsigned long twd_fxsr_to_i387( struct i387_fxsave_struct *fxsave )
 {
 	struct _fpxreg *st = NULL;
 	unsigned long twd = (unsigned long) fxsave->twd;
 	unsigned long tag;
 	unsigned long ret = 0xffff0000;
 	int i;

 #define FPREG_ADDR(f, n)	((char *)&(f)->st_space + (n) * 16);

 	for ( i = 0 ; i < 8 ; i++ ) {
 		if ( twd & 0x1 ) {
 			st = (struct _fpxreg *) FPREG_ADDR( fxsave, i );

 			switch ( st->exponent & 0x7fff ) {
 			case 0x7fff:
 				tag = 2;		/* Special */
 				break;
 			case 0x0000:
 				if ( !st->significand[0] &&
 				     !st->significand[1] &&
 				     !st->significand[2] &&
 				     !st->significand[3] ) {
 					tag = 1;	/* Zero */
 				} else {
 					tag = 2;	/* Special */
 				}
 				break;
 			default:
 				if ( st->significand[3] & 0x8000 ) {
 					tag = 0;	/* Valid */
 				} else {
 					tag = 2;	/* Special */
 				}
 				break;
 			}
 		} else {
 			tag = 3;			/* Empty */
 		}
 		ret |= (tag << (2 * i));
 		twd = twd >> 1;
 	}
 	return ret;
 }

 static inline int convert_fxsr_to_user(struct _fpstate __user *buf,
 				       struct pt_regs *regs)
 {
 	return(CHOOSE_MODE(convert_fxsr_to_user_tt(buf, regs), 0));
 }

 static inline int convert_fxsr_from_user(struct pt_regs *regs,
 					 struct _fpstate __user *buf)
 {
 	return(CHOOSE_MODE(convert_fxsr_from_user_tt(regs, buf), 0));
 }

 int get_fpregs(unsigned long buf, struct task_struct *child)
 {
 	int err;

 	err = convert_fxsr_to_user((struct _fpstate __user *) buf,
 				   &child->thread.regs);
 	if(err) return(-EFAULT);
 	else return(0);
 }

 int set_fpregs(unsigned long buf, struct task_struct *child)
 {
 	int err;

 	err = convert_fxsr_from_user(&child->thread.regs,
 				     (struct _fpstate __user *) buf);
 	if(err) return(-EFAULT);
 	else return(0);
 }

 int get_fpxregs(unsigned long buf, struct task_struct *tsk)
 {
 	return(CHOOSE_MODE(get_fpxregs_tt(buf, tsk), 0));
 }

 int set_fpxregs(unsigned long buf, struct task_struct *tsk)
 {
 	return(CHOOSE_MODE(set_fpxregs_tt(buf, tsk), 0));
 }

 #ifdef notdef
 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
 {
 	fpu->cwd = (((SC_FP_CW(PT_REGS_SC(regs)) & 0xffff) << 16) |
 		    (SC_FP_SW(PT_REGS_SC(regs)) & 0xffff));
 	fpu->swd = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff;
 	fpu->twd = SC_FP_IPOFF(PT_REGS_SC(regs));
 	fpu->fip = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff;
 	fpu->fcs = SC_FP_DATAOFF(PT_REGS_SC(regs));
 	fpu->foo = SC_FP_DATASEL(PT_REGS_SC(regs));
 	fpu->fos = 0;
 	memcpy(fpu->st_space, (void *) SC_FP_ST(PT_REGS_SC(regs)),
 	       sizeof(fpu->st_space));
 	return(1);
 }
 #endif

 static inline void copy_fpu_fxsave(struct pt_regs *regs,
 				   struct user_i387_struct *buf)
 {
 	(void) CHOOSE_MODE(copy_fpu_fxsave_tt(regs, buf), 0);
 }

 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu )
 {
 	copy_fpu_fxsave(regs, (struct user_i387_struct *) fpu);
 	return(1);
 }

 /*
  * Overrides for Emacs so that we follow Linus's tabbing style.
  * Emacs will notice this stuff at the end of the file and automatically
  * adjust the settings for this buffer only.  This must remain at the end
  * of the file.
  * ---------------------------------------------------------------------------
  * Local variables:
  * c-file-style: "linux"
  * End:
  */
	/*
	* Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
	* Licensed under the GPL
	*/

	#include <linux/compiler.h>
	#include "linux/sched.h"
	#include "linux/mm.h"
	#include "asm/elf.h"
	#include "asm/ptrace.h"
	#include "asm/uaccess.h"
	#include "asm/unistd.h"
	#include "sysdep/ptrace.h"
	#include "sysdep/sigcontext.h"
	#include "sysdep/sc.h"

	void arch_switch_to_skas(struct task_struct from, struct task_struct to)
	{
	int err = arch_switch_tls_skas(from, to);
	if (!err)
	return;

	if (err != -EINVAL)
	printk(KERN_WARNING "arch_switch_tls_skas failed, errno %d, not EINVAL\n", -err);
	else
	printk(KERN_WARNING "arch_switch_tls_skas failed, errno = EINVAL\n");
	}

	int is_syscall(unsigned long addr)
	{
	unsigned short instr;
	int n;

	n = copy_from_user(&instr, (void __user *) addr, sizeof(instr));
	if(n){
	/* access_process_vm() grants access to vsyscall and stub,
	* while copy_from_user doesn't. Maybe access_process_vm is
	* slow, but that doesn't matter, since it will be called only
	* in case of singlestepping, if copy_from_user failed.
	*/
	n = access_process_vm(current, addr, &instr, sizeof(instr), 0);
	if(n != sizeof(instr)) {
	printk("is_syscall : failed to read instruction from "
	"0x%lx\n", addr);
	return(1);
	}
	}
	/* int 0x80 or sysenter */
	return((instr == 0x80cd) \|\| (instr == 0x340f));
	}

	/* determines which flags the user has access to. */
	/* 1 = access 0 = no access */
	#define FLAG_MASK 0x00044dd5

	int putreg(struct task_struct *child, int regno, unsigned long value)
	{
	regno >>= 2;
	switch (regno) {
	case FS:
	if (value && (value & 3) != 3)
	return -EIO;
	PT_REGS_FS(&child->thread.regs) = value;
	return 0;
	case GS:
	if (value && (value & 3) != 3)
	return -EIO;
	PT_REGS_GS(&child->thread.regs) = value;
	return 0;
	case DS:
	case ES:
	if (value && (value & 3) != 3)
	return -EIO;
	value &= 0xffff;
	break;
	case SS:
	case CS:
	if ((value & 3) != 3)
	return -EIO;
	value &= 0xffff;
	break;
	case EFL:
	value &= FLAG_MASK;
	value \|= PT_REGS_EFLAGS(&child->thread.regs);
	break;
	}
	PT_REGS_SET(&child->thread.regs, regno, value);
	return 0;
	}

	int poke_user(struct task_struct *child, long addr, long data)
	{
	if ((addr & 3) \|\| addr < 0)
	return -EIO;

	if (addr < MAX_REG_OFFSET)
	return putreg(child, addr, data);

	else if((addr >= offsetof(struct user, u_debugreg[0])) &&
	(addr <= offsetof(struct user, u_debugreg[7]))){
	addr -= offsetof(struct user, u_debugreg[0]);
	addr = addr >> 2;
	if((addr == 4) \|\| (addr == 5)) return -EIO;
	child->thread.arch.debugregs[addr] = data;
	return 0;
	}
	return -EIO;
	}

	unsigned long getreg(struct task_struct *child, int regno)
	{
	unsigned long retval = ~0UL;

	regno >>= 2;
	switch (regno) {
	case FS:
	case GS:
	case DS:
	case ES:
	case SS:
	case CS:
	retval = 0xffff;
	/* fall through */
	default:
	retval &= PT_REG(&child->thread.regs, regno);
	}
	return retval;
	}

	int peek_user(struct task_struct *child, long addr, long data)
	{
	/* read the word at location addr in the USER area. */
	unsigned long tmp;

	if ((addr & 3) \|\| addr < 0)
	return -EIO;

	tmp = 0; /* Default return condition */
	if(addr < MAX_REG_OFFSET){
	tmp = getreg(child, addr);
	}
	else if((addr >= offsetof(struct user, u_debugreg[0])) &&
	(addr <= offsetof(struct user, u_debugreg[7]))){
	addr -= offsetof(struct user, u_debugreg[0]);
	addr = addr >> 2;
	tmp = child->thread.arch.debugregs[addr];
	}
	return put_user(tmp, (unsigned long __user *) data);
	}

	struct i387_fxsave_struct {
	unsigned short cwd;
	unsigned short swd;
	unsigned short twd;
	unsigned short fop;
	long fip;
	long fcs;
	long foo;
	long fos;
	long mxcsr;
	long reserved;
	long st_space[32]; /* 816 bytes for each FP-reg = 128 bytes /
	long xmm_space[32]; /* 816 bytes for each XMM-reg = 128 bytes /
	long padding[56];
	};

	/*
	* FPU tag word conversions.
	*/

	static inline unsigned short twd_i387_to_fxsr( unsigned short twd )
	{
	unsigned int tmp; /* to avoid 16 bit prefixes in the code */

	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
	tmp = ~twd;
	tmp = (tmp \| (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
	/* and move the valid bits to the lower byte. */
	tmp = (tmp \| (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
	tmp = (tmp \| (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
	tmp = (tmp \| (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
	return tmp;
	}

	static inline unsigned long twd_fxsr_to_i387( struct i387_fxsave_struct *fxsave )
	{
	struct _fpxreg *st = NULL;
	unsigned long twd = (unsigned long) fxsave->twd;
	unsigned long tag;
	unsigned long ret = 0xffff0000;
	int i;

	#define FPREG_ADDR(f, n) ((char )&(f)->st_space + (n) 16);

	for ( i = 0 ; i < 8 ; i++ ) {
	if ( twd & 0x1 ) {
	st = (struct _fpxreg *) FPREG_ADDR( fxsave, i );

	switch ( st->exponent & 0x7fff ) {
	case 0x7fff:
	tag = 2; /* Special */
	break;
	case 0x0000:
	if ( !st->significand[0] &&
	!st->significand[1] &&
	!st->significand[2] &&
	!st->significand[3] ) {
	tag = 1; /* Zero */
	} else {
	tag = 2; /* Special */
	}
	break;
	default:
	if ( st->significand[3] & 0x8000 ) {
	tag = 0; /* Valid */
	} else {
	tag = 2; /* Special */
	}
	break;
	}
	} else {
	tag = 3; /* Empty */
	}
	ret \|= (tag << (2 * i));
	twd = twd >> 1;
	}
	return ret;
	}

	static inline int convert_fxsr_to_user(struct _fpstate __user *buf,
	struct pt_regs *regs)
	{
	return(CHOOSE_MODE(convert_fxsr_to_user_tt(buf, regs), 0));
	}

	static inline int convert_fxsr_from_user(struct pt_regs *regs,
	struct _fpstate __user *buf)
	{
	return(CHOOSE_MODE(convert_fxsr_from_user_tt(regs, buf), 0));
	}

	int get_fpregs(unsigned long buf, struct task_struct *child)
	{
	int err;

	err = convert_fxsr_to_user((struct _fpstate __user *) buf,
	&child->thread.regs);
	if(err) return(-EFAULT);
	else return(0);
	}

	int set_fpregs(unsigned long buf, struct task_struct *child)
	{
	int err;

	err = convert_fxsr_from_user(&child->thread.regs,
	(struct _fpstate __user *) buf);
	if(err) return(-EFAULT);
	else return(0);
	}

	int get_fpxregs(unsigned long buf, struct task_struct *tsk)
	{
	return(CHOOSE_MODE(get_fpxregs_tt(buf, tsk), 0));
	}

	int set_fpxregs(unsigned long buf, struct task_struct *tsk)
	{
	return(CHOOSE_MODE(set_fpxregs_tt(buf, tsk), 0));
	}

	#ifdef notdef
	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpu)
	{
	fpu->cwd = (((SC_FP_CW(PT_REGS_SC(regs)) & 0xffff) << 16) \|
	(SC_FP_SW(PT_REGS_SC(regs)) & 0xffff));
	fpu->swd = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff;
	fpu->twd = SC_FP_IPOFF(PT_REGS_SC(regs));
	fpu->fip = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff;
	fpu->fcs = SC_FP_DATAOFF(PT_REGS_SC(regs));
	fpu->foo = SC_FP_DATASEL(PT_REGS_SC(regs));
	fpu->fos = 0;
	memcpy(fpu->st_space, (void *) SC_FP_ST(PT_REGS_SC(regs)),
	sizeof(fpu->st_space));
	return(1);
	}
	#endif

	static inline void copy_fpu_fxsave(struct pt_regs *regs,
	struct user_i387_struct *buf)
	{
	(void) CHOOSE_MODE(copy_fpu_fxsave_tt(regs, buf), 0);
	}

	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpu )
	{
	copy_fpu_fxsave(regs, (struct user_i387_struct *) fpu);
	return(1);
	}

	/*
	* Overrides for Emacs so that we follow Linus's tabbing style.
	* Emacs will notice this stuff at the end of the file and automatically
	* adjust the settings for this buffer only. This must remain at the end
	* of the file.
	* ---------------------------------------------------------------------------
	* Local variables:
	* c-file-style: "linux"
	* End:
	*/