Commit ea3d710f authored by Daniel Jacobowitz's avatar Daniel Jacobowitz Committed by Ralf Baechle
Browse files

Revise MIPS 64-bit ptrace interface 


    
Change the N32 debugging ABI to something more sane, and add support
for o32 and n32 debuggers to trace n64 programs.
    
Signed-off-by: default avatarDaniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 9043f7e9

arch/mips/kernel/ptrace.c

+129 −0
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ 
#include <asm/system.h>

#include <asm/uaccess.h>

#include <asm/bootinfo.h>

#include <asm/reg.h>



/*

 * Called by kernel/ptrace.c when detaching..
@@ -49,6 +50,118 @@ void ptrace_disable(struct task_struct *child) 
	/* Nothing to do.. */

}



/*

 * Read a general register set.  We always use the 64-bit format, even

 * for 32-bit kernels and for 32-bit processes on a 64-bit kernel.

 * Registers are sign extended to fill the available space.

 */

int ptrace_getregs (struct task_struct *child, __s64 __user *data)

{

	struct pt_regs *regs;

	int i;



	if (!access_ok(VERIFY_WRITE, data, 38 * 8))

		return -EIO;



	regs = (struct pt_regs *) ((unsigned long) child->thread_info +

	       THREAD_SIZE - 32 - sizeof(struct pt_regs));



	for (i = 0; i < 32; i++)

		__put_user (regs->regs[i], data + i);

	__put_user (regs->lo, data + EF_LO - EF_R0);

	__put_user (regs->hi, data + EF_HI - EF_R0);

	__put_user (regs->cp0_epc, data + EF_CP0_EPC - EF_R0);

	__put_user (regs->cp0_badvaddr, data + EF_CP0_BADVADDR - EF_R0);

	__put_user (regs->cp0_status, data + EF_CP0_STATUS - EF_R0);

	__put_user (regs->cp0_cause, data + EF_CP0_CAUSE - EF_R0);



	return 0;

}



/*

 * Write a general register set.  As for PTRACE_GETREGS, we always use

 * the 64-bit format.  On a 32-bit kernel only the lower order half

 * (according to endianness) will be used.

 */

int ptrace_setregs (struct task_struct *child, __s64 __user *data)

{

	struct pt_regs *regs;

	int i;



	if (!access_ok(VERIFY_READ, data, 38 * 8))

		return -EIO;



	regs = (struct pt_regs *) ((unsigned long) child->thread_info +

	       THREAD_SIZE - 32 - sizeof(struct pt_regs));



	for (i = 0; i < 32; i++)

		__get_user (regs->regs[i], data + i);

	__get_user (regs->lo, data + EF_LO - EF_R0);

	__get_user (regs->hi, data + EF_HI - EF_R0);

	__get_user (regs->cp0_epc, data + EF_CP0_EPC - EF_R0);



	/* badvaddr, status, and cause may not be written.  */



	return 0;

}



int ptrace_getfpregs (struct task_struct *child, __u32 __user *data)

{

	int i;



	if (!access_ok(VERIFY_WRITE, data, 33 * 8))

		return -EIO;



	if (tsk_used_math(child)) {

		fpureg_t *fregs = get_fpu_regs(child);

		for (i = 0; i < 32; i++)

			__put_user (fregs[i], i + (__u64 __user *) data);

	} else {

		for (i = 0; i < 32; i++)

			__put_user ((__u64) -1, i + (__u64 __user *) data);

	}



	if (cpu_has_fpu) {

		unsigned int flags, tmp;



		__put_user (child->thread.fpu.hard.fcr31, data + 64);



		flags = read_c0_status();

		__enable_fpu();

		__asm__ __volatile__("cfc1\t%0,$0" : "=r" (tmp));

		write_c0_status(flags);

		__put_user (tmp, data + 65);

	} else {

		__put_user (child->thread.fpu.soft.fcr31, data + 64);

		__put_user ((__u32) 0, data + 65);

	}



	return 0;

}



int ptrace_setfpregs (struct task_struct *child, __u32 __user *data)

{

	fpureg_t *fregs;

	int i;



	if (!access_ok(VERIFY_READ, data, 33 * 8))

		return -EIO;



	fregs = get_fpu_regs(child);



	for (i = 0; i < 32; i++)

		__get_user (fregs[i], i + (__u64 __user *) data);



	if (cpu_has_fpu)

		__get_user (child->thread.fpu.hard.fcr31, data + 64);

	else

		__get_user (child->thread.fpu.soft.fcr31, data + 64);



	/* FIR may not be written.  */



	return 0;

}



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

{

	struct task_struct *child;
@@ -300,6 +413,22 @@ asmlinkage int sys_ptrace(long request, long pid, long addr, long data) 
		break;

		}



	case PTRACE_GETREGS:

		ret = ptrace_getregs (child, (__u64 __user *) data);

		break;



	case PTRACE_SETREGS:

		ret = ptrace_setregs (child, (__u64 __user *) data);

		break;



	case PTRACE_GETFPREGS:

		ret = ptrace_getfpregs (child, (__u32 __user *) data);

		break;



	case PTRACE_SETFPREGS:

		ret = ptrace_setfpregs (child, (__u32 __user *) data);

		break;



	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */

	case PTRACE_CONT: { /* restart after signal. */

		ret = -EIO;

arch/mips/kernel/ptrace32.c

+81 −0
Original line number Diff line number Diff line
@@ -35,6 +35,12 @@ 
#include <asm/uaccess.h>

#include <asm/bootinfo.h>



int ptrace_getregs (struct task_struct *child, __s64 __user *data);

int ptrace_setregs (struct task_struct *child, __s64 __user *data);



int ptrace_getfpregs (struct task_struct *child, __u32 __user *data);

int ptrace_setfpregs (struct task_struct *child, __u32 __user *data);



/*

 * Tracing a 32-bit process with a 64-bit strace and vice versa will not

 * work.  I don't know how to fix this.
@@ -99,6 +105,35 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data) 
		break;

	}



	/*

	 * Read 4 bytes of the other process' storage

	 *  data is a pointer specifying where the user wants the

	 *	4 bytes copied into

	 *  addr is a pointer in the user's storage that contains an 8 byte

	 *	address in the other process of the 4 bytes that is to be read

	 * (this is run in a 32-bit process looking at a 64-bit process)

	 * when I and D space are separate, these will need to be fixed.

	 */

	case PTRACE_PEEKTEXT_3264:

	case PTRACE_PEEKDATA_3264: {

		u32 tmp;

		int copied;

		u32 __user * addrOthers;



		ret = -EIO;



		/* Get the addr in the other process that we want to read */

		if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)

			break;



		copied = access_process_vm(child, (u64)addrOthers, &tmp,

				sizeof(tmp), 0);

		if (copied != sizeof(tmp))

			break;

		ret = put_user(tmp, (u32 __user *) (unsigned long) data);

		break;

	}



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

	case PTRACE_PEEKUSR: {

		struct pt_regs *regs;
@@ -202,6 +237,31 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data) 
		ret = -EIO;

		break;



	/*

	 * Write 4 bytes into the other process' storage

	 *  data is the 4 bytes that the user wants written

	 *  addr is a pointer in the user's storage that contains an

	 *	8 byte address in the other process where the 4 bytes

	 *	that is to be written

	 * (this is run in a 32-bit process looking at a 64-bit process)

	 * when I and D space are separate, these will need to be fixed.

	 */

	case PTRACE_POKETEXT_3264:

	case PTRACE_POKEDATA_3264: {

		u32 __user * addrOthers;



		/* Get the addr in the other process that we want to write into */

		ret = -EIO;

		if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)

			break;

		ret = 0;

		if (access_process_vm(child, (u64)addrOthers, &data,

					sizeof(data), 1) == sizeof(data))

			break;

		ret = -EIO;

		break;

	}



	case PTRACE_POKEUSR: {

		struct pt_regs *regs;

		ret = 0;
@@ -276,6 +336,22 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data) 
		break;

		}



	case PTRACE_GETREGS:

		ret = ptrace_getregs (child, (__u64 __user *) (__u64) data);

		break;



	case PTRACE_SETREGS:

		ret = ptrace_setregs (child, (__u64 __user *) (__u64) data);

		break;



	case PTRACE_GETFPREGS:

		ret = ptrace_getfpregs (child, (__u32 __user *) (__u64) data);

		break;



	case PTRACE_SETFPREGS:

		ret = ptrace_setfpregs (child, (__u32 __user *) (__u64) data);

		break;



	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */

	case PTRACE_CONT: { /* restart after signal. */

		ret = -EIO;
@@ -320,6 +396,11 @@ asmlinkage int sys32_ptrace(int request, int pid, int addr, int data) 
			       (unsigned int __user *) (unsigned long) data);

		break;



	case PTRACE_GET_THREAD_AREA_3264:

		ret = put_user(child->thread_info->tp_value,

				(unsigned long __user *) (unsigned long) data);

		break;



	default:

		ret = ptrace_request(child, request, addr, data);

		break;

arch/mips/kernel/scall64-n32.S

+1 −1
Original line number Diff line number Diff line
@@ -216,7 +216,7 @@ EXPORT(sysn32_call_table) 
	PTR	compat_sys_getrusage

	PTR	sys32_sysinfo

	PTR	compat_sys_times

	PTR	sys_ptrace

	PTR	sys32_ptrace

	PTR	sys_getuid			/* 6100 */

	PTR	sys_syslog

	PTR	sys_getgid

include/asm-mips/ptrace.h

+11 −4
Original line number Diff line number Diff line
@@ -48,10 +48,10 @@ struct pt_regs { 
};



/* Arbitrarily choose the same ptrace numbers as used by the Sparc code. */

/* #define PTRACE_GETREGS		12 */

/* #define PTRACE_SETREGS		13 */

/* #define PTRACE_GETFPREGS		14 */

/* #define PTRACE_SETFPREGS		15 */

#define PTRACE_GETREGS		12

#define PTRACE_SETREGS		13

#define PTRACE_GETFPREGS		14

#define PTRACE_SETFPREGS		15

/* #define PTRACE_GETFPXREGS		18 */

/* #define PTRACE_SETFPXREGS		19 */
@@ -60,6 +60,13 @@ struct pt_regs { 
#define PTRACE_GET_THREAD_AREA	25

#define PTRACE_SET_THREAD_AREA	26



/* Calls to trace a 64bit program from a 32bit program.  */

#define PTRACE_PEEKTEXT_3264	0xc0

#define PTRACE_PEEKDATA_3264	0xc1

#define PTRACE_POKETEXT_3264	0xc2

#define PTRACE_POKEDATA_3264	0xc3

#define PTRACE_GET_THREAD_AREA_3264	0xc4



#ifdef __KERNEL__



#include <linux/linkage.h>