Commit 82c1c11b authored by Bodo Stroesser's avatar Bodo Stroesser Committed by Linus Torvalds
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[PATCH] uml: S390 preparation, peekusr/pokeusr defined by subarch 



s390 needs to change some parts of arch/um/kernel/ptrace.c.  Thus, the code
regarding PEEKUSER and POKEUSER are shifted to arch/um/sys-<subarch>/ptrace.c.

Also s390 debug registers need to be updated, when singlestepping is switched
on / off.  Thus, setting/resetting of singlestepping is centralized in the new
function set_singlestep(), which also inserts the macro
SUBARCH_SET_SINGLESTEP(mode), if defined.

Finally, s390 has the "ieee_instruction_pointer" in its
registers, which also is allowed to be read via

  ptrace( PTRACE_PEEKUSER, getpid(), PT_IEEE_IP, 0);

To implement this feature, sys_ptrace inserts the macro
SUBARCH_PTRACE_SPECIAL, if defined.

Signed-off-by: default avatarBodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 16c11163

arch/um/kernel/ptrace.c

+29 −50
Original line number Diff line number Diff line
@@ -19,15 +19,30 @@ 
#include "skas_ptrace.h"

#include "sysdep/ptrace.h"



static inline void set_singlestepping(struct task_struct *child, int on)

{

        if (on)

                child->ptrace |= PT_DTRACE;

        else

                child->ptrace &= ~PT_DTRACE;

        child->thread.singlestep_syscall = 0;



#ifdef SUBARCH_SET_SINGLESTEPPING

        SUBARCH_SET_SINGLESTEPPING(child, on)

#endif

                }



/*

 * Called by kernel/ptrace.c when detaching..

 */

void ptrace_disable(struct task_struct *child)

{ 

	child->ptrace &= ~PT_DTRACE;

	child->thread.singlestep_syscall = 0;

        set_singlestepping(child,0);

}



extern int peek_user(struct task_struct * child, long addr, long data);

extern int poke_user(struct task_struct * child, long addr, long data);



long sys_ptrace(long request, long pid, long addr, long data)

{

	struct task_struct *child;
@@ -67,6 +82,10 @@ long sys_ptrace(long request, long pid, long addr, long data) 
		goto out_tsk;

	}



#ifdef SUBACH_PTRACE_SPECIAL

        SUBARCH_PTRACE_SPECIAL(child,request,addr,data)

#endif



	ret = ptrace_check_attach(child, request == PTRACE_KILL);

	if (ret < 0)

		goto out_tsk;
@@ -87,28 +106,9 @@ long sys_ptrace(long request, long pid, long addr, long data) 
	}



	/* read the word at location addr in the USER area. */

	case PTRACE_PEEKUSR: {

		unsigned long tmp;



		ret = -EIO;

		if ((addr & 3) || addr < 0) 

			break;



		tmp = 0;  /* Default return condition */

		if(addr < MAX_REG_OFFSET){

			tmp = getreg(child, addr);

		}

#if defined(CONFIG_UML_X86) && !defined(CONFIG_64BIT)

		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];

		}

#endif

		ret = put_user(tmp, (unsigned long __user *) data);

        case PTRACE_PEEKUSR:

                ret = peek_user(child, addr, data);

                break;

	}



	/* when I and D space are separate, this will have to be fixed. */

	case PTRACE_POKETEXT: /* write the word at location addr. */
@@ -121,25 +121,7 @@ long sys_ptrace(long request, long pid, long addr, long data) 
		break;



	case PTRACE_POKEUSR: /* write the word at location addr in the USER area */

		ret = -EIO;

		if ((addr & 3) || addr < 0)

			break;



		if (addr < MAX_REG_OFFSET) {

			ret = putreg(child, addr, data);

			break;

		}

#if defined(CONFIG_UML_X86) && !defined(CONFIG_64BIT)

		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)) break;

			  child->thread.arch.debugregs[addr] = data;

			  ret = 0;

		}

#endif



                ret = poke_user(child, addr, data);

                break;



	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
@@ -148,8 +130,7 @@ long sys_ptrace(long request, long pid, long addr, long data) 
		if (!valid_signal(data))

			break;



		child->ptrace &= ~PT_DTRACE;

		child->thread.singlestep_syscall = 0;

                set_singlestepping(child, 0);

		if (request == PTRACE_SYSCALL) {

			set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);

		}
@@ -172,8 +153,7 @@ long sys_ptrace(long request, long pid, long addr, long data) 
		if (child->exit_state == EXIT_ZOMBIE)	/* already dead */

			break;



		child->ptrace &= ~PT_DTRACE;

		child->thread.singlestep_syscall = 0;

                set_singlestepping(child, 0);

		child->exit_code = SIGKILL;

		wake_up_process(child);

		break;
@@ -184,8 +164,7 @@ long sys_ptrace(long request, long pid, long addr, long data) 
		if (!valid_signal(data))

			break;

		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);

		child->ptrace |= PT_DTRACE;

		child->thread.singlestep_syscall = 0;

                set_singlestepping(child, 1);

		child->exit_code = data;

		/* give it a chance to run. */

		wake_up_process(child);

arch/um/sys-i386/ptrace.c

+40 −0
Original line number Diff line number Diff line
@@ -73,6 +73,25 @@ int putreg(struct task_struct *child, int regno, unsigned long 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;
@@ -93,6 +112,27 @@ unsigned long getreg(struct task_struct *child, int 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 *) data);

}



struct i387_fxsave_struct {

	unsigned short	cwd;

	unsigned short	swd;

arch/um/sys-ppc/ptrace.c

+40 −0
Original line number Diff line number Diff line
@@ -8,6 +8,25 @@ int putreg(struct task_struct *child, unsigned long regno, 
	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, unsigned long regno)

{

	unsigned long retval = ~0UL;
@@ -16,6 +35,27 @@ unsigned long getreg(struct task_struct *child, unsigned long 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 *) data);

}



/*

 * Overrides for Emacs so that we follow Linus's tabbing style.

 * Emacs will notice this stuff at the end of the file and automatically

arch/um/sys-x86_64/ptrace.c

+44 −0
Original line number Diff line number Diff line
@@ -62,6 +62,27 @@ int putreg(struct task_struct *child, int regno, unsigned long 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);



#if 0 /* Need x86_64 debugregs handling */

        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;

        }

#endif

        return -EIO;

}



unsigned long getreg(struct task_struct *child, int regno)

{

	unsigned long retval = ~0UL;
@@ -84,6 +105,29 @@ unsigned long getreg(struct task_struct *child, int 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);

        }

#if 0 /* Need x86_64 debugregs handling */

        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];

        }

#endif

        return put_user(tmp, (unsigned long *) data);

}



void arch_switch(void)

{

/* XXX

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