powerpc: Move ptrace32.c from arch/ppc64 to arch/powerpc

Also corrected my email address in ptrace.c and updated the comments
at the top of ptrace32.c.

Signed-off-by: Paul Mackerras <paulus@samba.org>

3 files changed, 452 insertions, 2 deletions

diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 01b6d630edc9..5c5d2b5f3ca2 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -12,7 +12,7 @@ endif
 
 obj-y				:= semaphore.o cputable.o ptrace.o syscalls.o \
 				   signal_32.o
-obj-$(CONFIG_PPC64)		+= binfmt_elf32.o sys_ppc32.o
+obj-$(CONFIG_PPC64)		+= binfmt_elf32.o sys_ppc32.o ptrace32.o
 obj-$(CONFIG_ALTIVEC)		+= vecemu.o vector.o
 obj-$(CONFIG_POWER4)		+= idle_power4.o
 obj-$(CONFIG_PPC_OF)		+= of_device.o
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 336b8bf542d7..943425a93354 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -8,7 +8,7 @@
  *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
  *
  * Modified by Cort Dougan (cort@hq.fsmlabs.com)
- * and Paul Mackerras (paulus@linuxcare.com.au).
+ * and Paul Mackerras (paulus@samba.org).
  *
  * This file is subject to the terms and conditions of the GNU General
  * Public License.  See the file README.legal in the main directory of
diff --git a/arch/powerpc/kernel/ptrace32.c b/arch/powerpc/kernel/ptrace32.c
new file mode 100644
index 000000000000..544368277d7e
--- /dev/null
+++ b/arch/powerpc/kernel/ptrace32.c
@@ -0,0 +1,450 @@
+/*
+ * ptrace for 32-bit processes running on a 64-bit kernel.
+ *
+ *  PowerPC version
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  Derived from "arch/m68k/kernel/ptrace.c"
+ *  Copyright (C) 1994 by Hamish Macdonald
+ *  Taken from linux/kernel/ptrace.c and modified for M680x0.
+ *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
+ *
+ * Modified by Cort Dougan (cort@hq.fsmlabs.com)
+ * and Paul Mackerras (paulus@samba.org).
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of
+ * this archive for more details.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/security.h>
+#include <linux/signal.h>
+
+#include <asm/uaccess.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/ptrace-common.h>
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+int compat_sys_ptrace(int request, int pid, unsigned long addr,
+		      unsigned long data)
+{
+	struct task_struct *child;
+	int ret = -EPERM;
+
+	lock_kernel();
+	if (request == PTRACE_TRACEME) {
+		/* are we already being traced? */
+		if (current->ptrace & PT_PTRACED)
+			goto out;
+		ret = security_ptrace(current->parent, current);
+		if (ret)
+			goto out;
+		/* set the ptrace bit in the process flags. */
+		current->ptrace |= PT_PTRACED;
+		ret = 0;
+		goto out;
+	}
+	ret = -ESRCH;
+	read_lock(&tasklist_lock);
+	child = find_task_by_pid(pid);
+	if (child)
+		get_task_struct(child);
+	read_unlock(&tasklist_lock);
+	if (!child)
+		goto out;
+
+	ret = -EPERM;
+	if (pid == 1)		/* you may not mess with init */
+		goto out_tsk;
+
+	if (request == PTRACE_ATTACH) {
+		ret = ptrace_attach(child);
+		goto out_tsk;
+	}
+
+	ret = ptrace_check_attach(child, request == PTRACE_KILL);
+	if (ret < 0)
+		goto out_tsk;
+
+	switch (request) {
+	/* when I and D space are separate, these will need to be fixed. */
+	case PTRACE_PEEKTEXT: /* read word at location addr. */ 
+	case PTRACE_PEEKDATA: {
+		unsigned int tmp;
+		int copied;
+
+		copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+		ret = -EIO;
+		if (copied != sizeof(tmp))
+			break;
+		ret = put_user(tmp, (u32 __user *)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 PPC_PTRACE_PEEKTEXT_3264:
+	case PPC_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 *)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 *)data);
+		break;
+	}
+
+	/* Read a register (specified by ADDR) out of the "user area" */
+	case PTRACE_PEEKUSR: {
+		int index;
+		unsigned long tmp;
+
+		ret = -EIO;
+		/* convert to index and check */
+		index = (unsigned long) addr >> 2;
+		if ((addr & 3) || (index > PT_FPSCR32))
+			break;
+
+		if (index < PT_FPR0) {
+			tmp = get_reg(child, index);
+		} else {
+			flush_fp_to_thread(child);
+			/*
+			 * the user space code considers the floating point
+			 * to be an array of unsigned int (32 bits) - the
+			 * index passed in is based on this assumption.
+			 */
+			tmp = ((unsigned int *)child->thread.fpr)[index - PT_FPR0];
+		}
+		ret = put_user((unsigned int)tmp, (u32 __user *)data);
+		break;
+	}
+  
+	/*
+	 * Read 4 bytes out of the other process' pt_regs area
+	 *  data is a pointer specifying where the user wants the
+	 *	4 bytes copied into
+	 *  addr is the offset into the other process' pt_regs structure
+	 *	that is to be read
+	 * (this is run in a 32-bit process looking at a 64-bit process)
+	 */
+	case PPC_PTRACE_PEEKUSR_3264: {
+		u32 index;
+		u32 reg32bits;
+		u64 tmp;
+		u32 numReg;
+		u32 part;
+
+		ret = -EIO;
+		/* Determine which register the user wants */
+		index = (u64)addr >> 2;
+		numReg = index / 2;
+		/* Determine which part of the register the user wants */
+		if (index % 2)
+			part = 1;  /* want the 2nd half of the register (right-most). */
+		else
+			part = 0;  /* want the 1st half of the register (left-most). */
+
+		/* Validate the input - check to see if address is on the wrong boundary or beyond the end of the user area */
+		if ((addr & 3) || numReg > PT_FPSCR)
+			break;
+
+		if (numReg >= PT_FPR0) {
+			flush_fp_to_thread(child);
+			tmp = ((unsigned long int *)child->thread.fpr)[numReg - PT_FPR0];
+		} else { /* register within PT_REGS struct */
+			tmp = get_reg(child, numReg);
+		} 
+		reg32bits = ((u32*)&tmp)[part];
+		ret = put_user(reg32bits, (u32 __user *)data);
+		break;
+	}
+
+	/* If I and D space are separate, this will have to be fixed. */
+	case PTRACE_POKETEXT: /* write the word at location addr. */
+	case PTRACE_POKEDATA: {
+		unsigned int tmp;
+		tmp = data;
+		ret = 0;
+		if (access_process_vm(child, addr, &tmp, sizeof(tmp), 1)
+				== sizeof(tmp))
+			break;
+		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 PPC_PTRACE_POKETEXT_3264:
+	case PPC_PTRACE_POKEDATA_3264: {
+		u32 tmp = data;
+		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 *)addr) != 0)
+			break;
+		ret = 0;
+		if (access_process_vm(child, (u64)addrOthers, &tmp,
+					sizeof(tmp), 1) == sizeof(tmp))
+			break;
+		ret = -EIO;
+		break;
+	}
+
+	/* write the word at location addr in the USER area */
+	case PTRACE_POKEUSR: {
+		unsigned long index;
+
+		ret = -EIO;
+		/* convert to index and check */
+		index = (unsigned long) addr >> 2;
+		if ((addr & 3) || (index > PT_FPSCR32))
+			break;
+
+		if (index == PT_ORIG_R3)
+			break;
+		if (index < PT_FPR0) {
+			ret = put_reg(child, index, data);
+		} else {
+			flush_fp_to_thread(child);
+			/*
+			 * the user space code considers the floating point
+			 * to be an array of unsigned int (32 bits) - the
+			 * index passed in is based on this assumption.
+			 */
+			((unsigned int *)child->thread.fpr)[index - PT_FPR0] = data;
+			ret = 0;
+		}
+		break;
+	}
+
+	/*
+	 * Write 4 bytes into the other process' pt_regs area
+	 *  data is the 4 bytes that the user wants written
+	 *  addr is the offset into the other process' pt_regs structure
+	 *	that is to be written into
+	 * (this is run in a 32-bit process looking at a 64-bit process)
+	 */
+	case PPC_PTRACE_POKEUSR_3264: {
+		u32 index;
+		u32 numReg;
+
+		ret = -EIO;
+		/* Determine which register the user wants */
+		index = (u64)addr >> 2;
+		numReg = index / 2;
+		/*
+		 * Validate the input - check to see if address is on the
+		 * wrong boundary or beyond the end of the user area
+		 */
+		if ((addr & 3) || (numReg > PT_FPSCR))
+			break;
+		/* Insure it is a register we let them change */
+		if ((numReg == PT_ORIG_R3)
+				|| ((numReg > PT_CCR) && (numReg < PT_FPR0)))
+			break;
+		if (numReg >= PT_FPR0) {
+			flush_fp_to_thread(child);
+		}
+		if (numReg == PT_MSR)
+			data = (data & MSR_DEBUGCHANGE)
+				| (child->thread.regs->msr & ~MSR_DEBUGCHANGE);
+		((u32*)child->thread.regs)[index] = data;
+		ret = 0;
+		break;
+	}
+
+	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+	case PTRACE_CONT: { /* restart after signal. */
+		ret = -EIO;
+		if (!valid_signal(data))
+			break;
+		if (request == PTRACE_SYSCALL)
+			set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		else
+			clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		child->exit_code = data;
+		/* make sure the single step bit is not set. */
+		clear_single_step(child);
+		wake_up_process(child);
+		ret = 0;
+		break;
+	}
+
+	/*
+	 * make the child exit.  Best I can do is send it a sigkill.
+	 * perhaps it should be put in the status that it wants to
+	 * exit.
+	 */
+	case PTRACE_KILL: {
+		ret = 0;
+		if (child->exit_state == EXIT_ZOMBIE)	/* already dead */
+			break;
+		child->exit_code = SIGKILL;
+		/* make sure the single step bit is not set. */
+		clear_single_step(child);
+		wake_up_process(child);
+		break;
+	}
+
+	case PTRACE_SINGLESTEP: {  /* set the trap flag. */
+		ret = -EIO;
+		if (!valid_signal(data))
+			break;
+		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		set_single_step(child);
+		child->exit_code = data;
+		/* give it a chance to run. */
+		wake_up_process(child);
+		ret = 0;
+		break;
+	}
+
+	case PTRACE_GET_DEBUGREG: {
+		ret = -EINVAL;
+		/* We only support one DABR and no IABRS at the moment */
+		if (addr > 0)
+			break;
+		ret = put_user(child->thread.dabr, (u32 __user *)data);
+		break;
+	}
+
+	case PTRACE_SET_DEBUGREG:
+		ret = ptrace_set_debugreg(child, addr, data);
+		break;
+
+	case PTRACE_DETACH:
+		ret = ptrace_detach(child, data);
+		break;
+
+	case PPC_PTRACE_GETREGS: { /* Get GPRs 0 - 31. */
+		int i;
+		unsigned long *reg = &((unsigned long *)child->thread.regs)[0];
+		unsigned int __user *tmp = (unsigned int __user *)addr;
+
+		for (i = 0; i < 32; i++) {
+			ret = put_user(*reg, tmp);
+			if (ret)
+				break;
+			reg++;
+			tmp++;
+		}
+		break;
+	}
+
+	case PPC_PTRACE_SETREGS: { /* Set GPRs 0 - 31. */
+		int i;
+		unsigned long *reg = &((unsigned long *)child->thread.regs)[0];
+		unsigned int __user *tmp = (unsigned int __user *)addr;
+
+		for (i = 0; i < 32; i++) {
+			ret = get_user(*reg, tmp);
+			if (ret)
+				break;
+			reg++;
+			tmp++;
+		}
+		break;
+	}
+
+	case PPC_PTRACE_GETFPREGS: { /* Get FPRs 0 - 31. */
+		int i;
+		unsigned long *reg = &((unsigned long *)child->thread.fpr)[0];
+		unsigned int __user *tmp = (unsigned int __user *)addr;
+
+		flush_fp_to_thread(child);
+
+		for (i = 0; i < 32; i++) {
+			ret = put_user(*reg, tmp);
+			if (ret)
+				break;
+			reg++;
+			tmp++;
+		}
+		break;
+	}
+
+	case PPC_PTRACE_SETFPREGS: { /* Get FPRs 0 - 31. */
+		int i;
+		unsigned long *reg = &((unsigned long *)child->thread.fpr)[0];
+		unsigned int __user *tmp = (unsigned int __user *)addr;
+
+		flush_fp_to_thread(child);
+
+		for (i = 0; i < 32; i++) {
+			ret = get_user(*reg, tmp);
+			if (ret)
+				break;
+			reg++;
+			tmp++;
+		}
+		break;
+	}
+
+	case PTRACE_GETEVENTMSG:
+		ret = put_user(child->ptrace_message, (unsigned int __user *) data);
+		break;
+
+#ifdef CONFIG_ALTIVEC
+	case PTRACE_GETVRREGS:
+		/* Get the child altivec register state. */
+		flush_altivec_to_thread(child);
+		ret = get_vrregs((unsigned long __user *)data, child);
+		break;
+
+	case PTRACE_SETVRREGS:
+		/* Set the child altivec register state. */
+		flush_altivec_to_thread(child);
+		ret = set_vrregs(child, (unsigned long __user *)data);
+		break;
+#endif
+
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+out_tsk:
+	put_task_struct(child);
+out:
+	unlock_kernel();
+	return ret;
+}