arch/parisc/kernel/ptrace.c - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Kernel support for the ptrace() and syscall tracing interfaces.
  *
  * Copyright (C) 2000 Hewlett-Packard Co, Linuxcare Inc.
  * Copyright (C) 2000 Matthew Wilcox <matthew@wil.cx>
  * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
  * Copyright (C) 2008-2016 Helge Deller <deller@gmx.de>
  */

 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
 #include <linux/elf.h>
 #include <linux/errno.h>
 #include <linux/ptrace.h>
 #include <linux/tracehook.h>
 #include <linux/user.h>
 #include <linux/personality.h>
 #include <linux/regset.h>
 #include <linux/security.h>
 #include <linux/seccomp.h>
 #include <linux/compat.h>
 #include <linux/signal.h>
 #include <linux/audit.h>

 #include <linux/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/processor.h>
 #include <asm/asm-offsets.h>

 /* PSW bits we allow the debugger to modify */
 #define USER_PSW_BITS	(PSW_N | PSW_B | PSW_V | PSW_CB)

 #define CREATE_TRACE_POINTS
 #include <trace/events/syscalls.h>

 /*
  * These are our native regset flavors.
  */
 enum parisc_regset {
 	REGSET_GENERAL,
 	REGSET_FP
 };

 /*
  * Called by kernel/ptrace.c when detaching..
  *
  * Make sure single step bits etc are not set.
  */
 void ptrace_disable(struct task_struct *task)
 {
 	clear_tsk_thread_flag(task, TIF_SINGLESTEP);
 	clear_tsk_thread_flag(task, TIF_BLOCKSTEP);

 	/* make sure the trap bits are not set */
 	pa_psw(task)->r = 0;
 	pa_psw(task)->t = 0;
 	pa_psw(task)->h = 0;
 	pa_psw(task)->l = 0;
 }

 /*
  * The following functions are called by ptrace_resume() when
  * enabling or disabling single/block tracing.
  */
 void user_disable_single_step(struct task_struct *task)
 {
 	ptrace_disable(task);
 }

 void user_enable_single_step(struct task_struct *task)
 {
 	clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
 	set_tsk_thread_flag(task, TIF_SINGLESTEP);

 	if (pa_psw(task)->n) {
 		struct siginfo si;

 		/* Nullified, just crank over the queue. */
 		task_regs(task)->iaoq[0] = task_regs(task)->iaoq[1];
 		task_regs(task)->iasq[0] = task_regs(task)->iasq[1];
 		task_regs(task)->iaoq[1] = task_regs(task)->iaoq[0] + 4;
 		pa_psw(task)->n = 0;
 		pa_psw(task)->x = 0;
 		pa_psw(task)->y = 0;
 		pa_psw(task)->z = 0;
 		pa_psw(task)->b = 0;
 		ptrace_disable(task);
 		/* Don't wake up the task, but let the
 		   parent know something happened. */
 		si.si_code = TRAP_TRACE;
 		si.si_addr = (void __user *) (task_regs(task)->iaoq[0] & ~3);
 		si.si_signo = SIGTRAP;
 		si.si_errno = 0;
 		force_sig_info(SIGTRAP, &si, task);
 		/* notify_parent(task, SIGCHLD); */
 		return;
 	}

 	/* Enable recovery counter traps.  The recovery counter
 	 * itself will be set to zero on a task switch.  If the
 	 * task is suspended on a syscall then the syscall return
 	 * path will overwrite the recovery counter with a suitable
 	 * value such that it traps once back in user space.  We
 	 * disable interrupts in the tasks PSW here also, to avoid
 	 * interrupts while the recovery counter is decrementing.
 	 */
 	pa_psw(task)->r = 1;
 	pa_psw(task)->t = 0;
 	pa_psw(task)->h = 0;
 	pa_psw(task)->l = 0;
 }

 void user_enable_block_step(struct task_struct *task)
 {
 	clear_tsk_thread_flag(task, TIF_SINGLESTEP);
 	set_tsk_thread_flag(task, TIF_BLOCKSTEP);

 	/* Enable taken branch trap. */
 	pa_psw(task)->r = 0;
 	pa_psw(task)->t = 1;
 	pa_psw(task)->h = 0;
 	pa_psw(task)->l = 0;
 }

 long arch_ptrace(struct task_struct *child, long request,
 		 unsigned long addr, unsigned long data)
 {
 	unsigned long __user *datap = (unsigned long __user *)data;
 	unsigned long tmp;
 	long ret = -EIO;

 	unsigned long user_regs_struct_size = sizeof(struct user_regs_struct);
 #ifdef CONFIG_64BIT
 	if (is_compat_task())
 		user_regs_struct_size /= 2;
 #endif

 	switch (request) {

 	/* Read the word at location addr in the USER area.  For ptraced
 	   processes, the kernel saves all regs on a syscall. */
 	case PTRACE_PEEKUSR:
 		if ((addr & (sizeof(unsigned long)-1)) ||
 		     addr >= sizeof(struct pt_regs))
 			break;
 		tmp = *(unsigned long *) ((char *) task_regs(child) + addr);
 		ret = put_user(tmp, datap);
 		break;

 	/* Write the word at location addr in the USER area.  This will need
 	   to change when the kernel no longer saves all regs on a syscall.
 	   FIXME.  There is a problem at the moment in that r3-r18 are only
 	   saved if the process is ptraced on syscall entry, and even then
 	   those values are overwritten by actual register values on syscall
 	   exit. */
 	case PTRACE_POKEUSR:
 		/* Some register values written here may be ignored in
 		 * entry.S:syscall_restore_rfi; e.g. iaoq is written with
 		 * r31/r31+4, and not with the values in pt_regs.
 		 */
 		if (addr == PT_PSW) {
 			/* Allow writing to Nullify, Divide-step-correction,
 			 * and carry/borrow bits.
 			 * BEWARE, if you set N, and then single step, it won't
 			 * stop on the nullified instruction.
 			 */
 			data &= USER_PSW_BITS;
 			task_regs(child)->gr[0] &= ~USER_PSW_BITS;
 			task_regs(child)->gr[0] |= data;
 			ret = 0;
 			break;
 		}

 		if ((addr & (sizeof(unsigned long)-1)) ||
 		     addr >= sizeof(struct pt_regs))
 			break;
 		if (addr == PT_IAOQ0 || addr == PT_IAOQ1) {
 			data |= 3; /* ensure userspace privilege */
 		}
 		if ((addr >= PT_GR1 && addr <= PT_GR31) ||
 				addr == PT_IAOQ0 || addr == PT_IAOQ1 ||
 				(addr >= PT_FR0 && addr <= PT_FR31 + 4) ||
 				addr == PT_SAR) {
 			*(unsigned long *) ((char *) task_regs(child) + addr) = data;
 			ret = 0;
 		}
 		break;

 	case PTRACE_GETREGS:	/* Get all gp regs from the child. */
 		return copy_regset_to_user(child,
 					   task_user_regset_view(current),
 					   REGSET_GENERAL,
 					   0, user_regs_struct_size,
 					   datap);

 	case PTRACE_SETREGS:	/* Set all gp regs in the child. */
 		return copy_regset_from_user(child,
 					     task_user_regset_view(current),
 					     REGSET_GENERAL,
 					     0, user_regs_struct_size,
 					     datap);

 	case PTRACE_GETFPREGS:	/* Get the child FPU state. */
 		return copy_regset_to_user(child,
 					   task_user_regset_view(current),
 					   REGSET_FP,
 					   0, sizeof(struct user_fp_struct),
 					   datap);

 	case PTRACE_SETFPREGS:	/* Set the child FPU state. */
 		return copy_regset_from_user(child,
 					     task_user_regset_view(current),
 					     REGSET_FP,
 					     0, sizeof(struct user_fp_struct),
 					     datap);

 	default:
 		ret = ptrace_request(child, request, addr, data);
 		break;
 	}

 	return ret;
 }


 #ifdef CONFIG_COMPAT

 /* This function is needed to translate 32 bit pt_regs offsets in to
  * 64 bit pt_regs offsets.  For example, a 32 bit gdb under a 64 bit kernel
  * will request offset 12 if it wants gr3, but the lower 32 bits of
  * the 64 bit kernels view of gr3 will be at offset 28 (3*8 + 4).
  * This code relies on a 32 bit pt_regs being comprised of 32 bit values
  * except for the fp registers which (a) are 64 bits, and (b) follow
  * the gr registers at the start of pt_regs.  The 32 bit pt_regs should
  * be half the size of the 64 bit pt_regs, plus 32*4 to allow for fr[]
  * being 64 bit in both cases.
  */

 static compat_ulong_t translate_usr_offset(compat_ulong_t offset)
 {
 	compat_ulong_t pos;

 	if (offset < 32*4)	/* gr[0..31] */
 		pos = offset * 2 + 4;
 	else if (offset < 32*4+32*8)	/* fr[0] ... fr[31] */
 		pos = (offset - 32*4) + PT_FR0;
 	else if (offset < sizeof(struct pt_regs)/2 + 32*4) /* sr[0] ... ipsw */
 		pos = (offset - 32*4 - 32*8) * 2 + PT_SR0 + 4;
 	else
 		pos = sizeof(struct pt_regs);

 	return pos;
 }

 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 			compat_ulong_t addr, compat_ulong_t data)
 {
 	compat_uint_t tmp;
 	long ret = -EIO;

 	switch (request) {

 	case PTRACE_PEEKUSR:
 		if (addr & (sizeof(compat_uint_t)-1))
 			break;
 		addr = translate_usr_offset(addr);
 		if (addr >= sizeof(struct pt_regs))
 			break;

 		tmp = *(compat_uint_t *) ((char *) task_regs(child) + addr);
 		ret = put_user(tmp, (compat_uint_t *) (unsigned long) data);
 		break;

 	/* Write the word at location addr in the USER area.  This will need
 	   to change when the kernel no longer saves all regs on a syscall.
 	   FIXME.  There is a problem at the moment in that r3-r18 are only
 	   saved if the process is ptraced on syscall entry, and even then
 	   those values are overwritten by actual register values on syscall
 	   exit. */
 	case PTRACE_POKEUSR:
 		/* Some register values written here may be ignored in
 		 * entry.S:syscall_restore_rfi; e.g. iaoq is written with
 		 * r31/r31+4, and not with the values in pt_regs.
 		 */
 		if (addr == PT_PSW) {
 			/* Since PT_PSW==0, it is valid for 32 bit processes
 			 * under 64 bit kernels as well.
 			 */
 			ret = arch_ptrace(child, request, addr, data);
 		} else {
 			if (addr & (sizeof(compat_uint_t)-1))
 				break;
 			addr = translate_usr_offset(addr);
 			if (addr >= sizeof(struct pt_regs))
 				break;
 			if (addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4) {
 				data |= 3; /* ensure userspace privilege */
 			}
 			if (addr >= PT_FR0 && addr <= PT_FR31 + 4) {
 				/* Special case, fp regs are 64 bits anyway */
 				*(__u32 *) ((char *) task_regs(child) + addr) = data;
 				ret = 0;
 			}
 			else if ((addr >= PT_GR1+4 && addr <= PT_GR31+4) ||
 					addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4 ||
 					addr == PT_SAR+4) {
 				/* Zero the top 32 bits */
 				*(__u32 *) ((char *) task_regs(child) + addr - 4) = 0;
 				*(__u32 *) ((char *) task_regs(child) + addr) = data;
 				ret = 0;
 			}
 		}
 		break;
 	case PTRACE_GETREGS:
 	case PTRACE_SETREGS:
 	case PTRACE_GETFPREGS:
 	case PTRACE_SETFPREGS:
 		return arch_ptrace(child, request, addr, data);

 	default:
 		ret = compat_ptrace_request(child, request, addr, data);
 		break;
 	}

 	return ret;
 }
 #endif

 long do_syscall_trace_enter(struct pt_regs *regs)
 {
 	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
 		int rc = tracehook_report_syscall_entry(regs);

 		/*
 		 * As tracesys_next does not set %r28 to -ENOSYS
 		 * when %r20 is set to -1, initialize it here.
 		 */
 		regs->gr[28] = -ENOSYS;

 		if (rc) {
 			/*
 			 * A nonzero return code from
 			 * tracehook_report_syscall_entry() tells us
 			 * to prevent the syscall execution.  Skip
 			 * the syscall call and the syscall restart handling.
 			 *
 			 * Note that the tracer may also just change
 			 * regs->gr[20] to an invalid syscall number,
 			 * that is handled by tracesys_next.
 			 */
 			regs->gr[20] = -1UL;
 			return -1;
 		}
 	}

 	/* Do the secure computing check after ptrace. */
 	if (secure_computing(NULL) == -1)
 		return -1;

 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 		trace_sys_enter(regs, regs->gr[20]);
 #endif

 #ifdef CONFIG_64BIT
 	if (!is_compat_task())
 		audit_syscall_entry(regs->gr[20], regs->gr[26], regs->gr[25],
 				    regs->gr[24], regs->gr[23]);
 	else
 #endif
 		audit_syscall_entry(regs->gr[20] & 0xffffffff,
 			regs->gr[26] & 0xffffffff,
 			regs->gr[25] & 0xffffffff,
 			regs->gr[24] & 0xffffffff,
 			regs->gr[23] & 0xffffffff);

 	/*
 	 * Sign extend the syscall number to 64bit since it may have been
 	 * modified by a compat ptrace call
 	 */
 	return (int) ((u32) regs->gr[20]);
 }

 void do_syscall_trace_exit(struct pt_regs *regs)
 {
 	int stepping = test_thread_flag(TIF_SINGLESTEP) ||
 		test_thread_flag(TIF_BLOCKSTEP);

 	audit_syscall_exit(regs);

 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 		trace_sys_exit(regs, regs->gr[20]);
 #endif

 	if (stepping || test_thread_flag(TIF_SYSCALL_TRACE))
 		tracehook_report_syscall_exit(regs, stepping);
 }


 /*
  * regset functions.
  */

 static int fpr_get(struct task_struct *target,
 		     const struct user_regset *regset,
 		     unsigned int pos, unsigned int count,
 		     void *kbuf, void __user *ubuf)
 {
 	struct pt_regs *regs = task_regs(target);
 	__u64 *k = kbuf;
 	__u64 __user *u = ubuf;
 	__u64 reg;

 	pos /= sizeof(reg);
 	count /= sizeof(reg);

 	if (kbuf)
 		for (; count > 0 && pos < ELF_NFPREG; --count)
 			*k++ = regs->fr[pos++];
 	else
 		for (; count > 0 && pos < ELF_NFPREG; --count)
 			if (__put_user(regs->fr[pos++], u++))
 				return -EFAULT;

 	kbuf = k;
 	ubuf = u;
 	pos *= sizeof(reg);
 	count *= sizeof(reg);
 	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 					ELF_NFPREG * sizeof(reg), -1);
 }

 static int fpr_set(struct task_struct *target,
 		     const struct user_regset *regset,
 		     unsigned int pos, unsigned int count,
 		     const void *kbuf, const void __user *ubuf)
 {
 	struct pt_regs *regs = task_regs(target);
 	const __u64 *k = kbuf;
 	const __u64 __user *u = ubuf;
 	__u64 reg;

 	pos /= sizeof(reg);
 	count /= sizeof(reg);

 	if (kbuf)
 		for (; count > 0 && pos < ELF_NFPREG; --count)
 			regs->fr[pos++] = *k++;
 	else
 		for (; count > 0 && pos < ELF_NFPREG; --count) {
 			if (__get_user(reg, u++))
 				return -EFAULT;
 			regs->fr[pos++] = reg;
 		}

 	kbuf = k;
 	ubuf = u;
 	pos *= sizeof(reg);
 	count *= sizeof(reg);
 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 					 ELF_NFPREG * sizeof(reg), -1);
 }

 #define RI(reg) (offsetof(struct user_regs_struct,reg) / sizeof(long))

 static unsigned long get_reg(struct pt_regs *regs, int num)
 {
 	switch (num) {
 	case RI(gr[0]) ... RI(gr[31]):	return regs->gr[num - RI(gr[0])];
 	case RI(sr[0]) ... RI(sr[7]):	return regs->sr[num - RI(sr[0])];
 	case RI(iasq[0]):		return regs->iasq[0];
 	case RI(iasq[1]):		return regs->iasq[1];
 	case RI(iaoq[0]):		return regs->iaoq[0];
 	case RI(iaoq[1]):		return regs->iaoq[1];
 	case RI(sar):			return regs->sar;
 	case RI(iir):			return regs->iir;
 	case RI(isr):			return regs->isr;
 	case RI(ior):			return regs->ior;
 	case RI(ipsw):			return regs->ipsw;
 	case RI(cr27):			return regs->cr27;
 	case RI(cr0):			return mfctl(0);
 	case RI(cr24):			return mfctl(24);
 	case RI(cr25):			return mfctl(25);
 	case RI(cr26):			return mfctl(26);
 	case RI(cr28):			return mfctl(28);
 	case RI(cr29):			return mfctl(29);
 	case RI(cr30):			return mfctl(30);
 	case RI(cr31):			return mfctl(31);
 	case RI(cr8):			return mfctl(8);
 	case RI(cr9):			return mfctl(9);
 	case RI(cr12):			return mfctl(12);
 	case RI(cr13):			return mfctl(13);
 	case RI(cr10):			return mfctl(10);
 	case RI(cr15):			return mfctl(15);
 	default:			return 0;
 	}
 }

 static void set_reg(struct pt_regs *regs, int num, unsigned long val)
 {
 	switch (num) {
 	case RI(gr[0]): /*
 			 * PSW is in gr[0].
 			 * Allow writing to Nullify, Divide-step-correction,
 			 * and carry/borrow bits.
 			 * BEWARE, if you set N, and then single step, it won't
 			 * stop on the nullified instruction.
 			 */
 			val &= USER_PSW_BITS;
 			regs->gr[0] &= ~USER_PSW_BITS;
 			regs->gr[0] |= val;
 			return;
 	case RI(gr[1]) ... RI(gr[31]):
 			regs->gr[num - RI(gr[0])] = val;
 			return;
 	case RI(iaoq[0]):
 	case RI(iaoq[1]):
 			/* set 2 lowest bits to ensure userspace privilege: */
 			regs->iaoq[num - RI(iaoq[0])] = val | 3;
 			return;
 	case RI(sar):	regs->sar = val;
 			return;
 	default:	return;
 #if 0
 	/* do not allow to change any of the following registers (yet) */
 	case RI(sr[0]) ... RI(sr[7]):	return regs->sr[num - RI(sr[0])];
 	case RI(iasq[0]):		return regs->iasq[0];
 	case RI(iasq[1]):		return regs->iasq[1];
 	case RI(iir):			return regs->iir;
 	case RI(isr):			return regs->isr;
 	case RI(ior):			return regs->ior;
 	case RI(ipsw):			return regs->ipsw;
 	case RI(cr27):			return regs->cr27;
         case cr0, cr24, cr25, cr26, cr27, cr28, cr29, cr30, cr31;
         case cr8, cr9, cr12, cr13, cr10, cr15;
 #endif
 	}
 }

 static int gpr_get(struct task_struct *target,
 		     const struct user_regset *regset,
 		     unsigned int pos, unsigned int count,
 		     void *kbuf, void __user *ubuf)
 {
 	struct pt_regs *regs = task_regs(target);
 	unsigned long *k = kbuf;
 	unsigned long __user *u = ubuf;
 	unsigned long reg;

 	pos /= sizeof(reg);
 	count /= sizeof(reg);

 	if (kbuf)
 		for (; count > 0 && pos < ELF_NGREG; --count)
 			*k++ = get_reg(regs, pos++);
 	else
 		for (; count > 0 && pos < ELF_NGREG; --count)
 			if (__put_user(get_reg(regs, pos++), u++))
 				return -EFAULT;
 	kbuf = k;
 	ubuf = u;
 	pos *= sizeof(reg);
 	count *= sizeof(reg);
 	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 					ELF_NGREG * sizeof(reg), -1);
 }

 static int gpr_set(struct task_struct *target,
 		     const struct user_regset *regset,
 		     unsigned int pos, unsigned int count,
 		     const void *kbuf, const void __user *ubuf)
 {
 	struct pt_regs *regs = task_regs(target);
 	const unsigned long *k = kbuf;
 	const unsigned long __user *u = ubuf;
 	unsigned long reg;

 	pos /= sizeof(reg);
 	count /= sizeof(reg);

 	if (kbuf)
 		for (; count > 0 && pos < ELF_NGREG; --count)
 			set_reg(regs, pos++, *k++);
 	else
 		for (; count > 0 && pos < ELF_NGREG; --count) {
 			if (__get_user(reg, u++))
 				return -EFAULT;
 			set_reg(regs, pos++, reg);
 		}

 	kbuf = k;
 	ubuf = u;
 	pos *= sizeof(reg);
 	count *= sizeof(reg);
 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 					 ELF_NGREG * sizeof(reg), -1);
 }

 static const struct user_regset native_regsets[] = {
 	[REGSET_GENERAL] = {
 		.core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
 		.size = sizeof(long), .align = sizeof(long),
 		.get = gpr_get, .set = gpr_set
 	},
 	[REGSET_FP] = {
 		.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
 		.size = sizeof(__u64), .align = sizeof(__u64),
 		.get = fpr_get, .set = fpr_set
 	}
 };

 static const struct user_regset_view user_parisc_native_view = {
 	.name = "parisc", .e_machine = ELF_ARCH, .ei_osabi = ELFOSABI_LINUX,
 	.regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
 };

 #ifdef CONFIG_64BIT
 #include <linux/compat.h>

 static int gpr32_get(struct task_struct *target,
 		     const struct user_regset *regset,
 		     unsigned int pos, unsigned int count,
 		     void *kbuf, void __user *ubuf)
 {
 	struct pt_regs *regs = task_regs(target);
 	compat_ulong_t *k = kbuf;
 	compat_ulong_t __user *u = ubuf;
 	compat_ulong_t reg;

 	pos /= sizeof(reg);
 	count /= sizeof(reg);

 	if (kbuf)
 		for (; count > 0 && pos < ELF_NGREG; --count)
 			*k++ = get_reg(regs, pos++);
 	else
 		for (; count > 0 && pos < ELF_NGREG; --count)
 			if (__put_user((compat_ulong_t) get_reg(regs, pos++), u++))
 				return -EFAULT;

 	kbuf = k;
 	ubuf = u;
 	pos *= sizeof(reg);
 	count *= sizeof(reg);
 	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 					ELF_NGREG * sizeof(reg), -1);
 }

 static int gpr32_set(struct task_struct *target,
 		     const struct user_regset *regset,
 		     unsigned int pos, unsigned int count,
 		     const void *kbuf, const void __user *ubuf)
 {
 	struct pt_regs *regs = task_regs(target);
 	const compat_ulong_t *k = kbuf;
 	const compat_ulong_t __user *u = ubuf;
 	compat_ulong_t reg;

 	pos /= sizeof(reg);
 	count /= sizeof(reg);

 	if (kbuf)
 		for (; count > 0 && pos < ELF_NGREG; --count)
 			set_reg(regs, pos++, *k++);
 	else
 		for (; count > 0 && pos < ELF_NGREG; --count) {
 			if (__get_user(reg, u++))
 				return -EFAULT;
 			set_reg(regs, pos++, reg);
 		}

 	kbuf = k;
 	ubuf = u;
 	pos *= sizeof(reg);
 	count *= sizeof(reg);
 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 					 ELF_NGREG * sizeof(reg), -1);
 }

 /*
  * These are the regset flavors matching the 32bit native set.
  */
 static const struct user_regset compat_regsets[] = {
 	[REGSET_GENERAL] = {
 		.core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
 		.size = sizeof(compat_long_t), .align = sizeof(compat_long_t),
 		.get = gpr32_get, .set = gpr32_set
 	},
 	[REGSET_FP] = {
 		.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
 		.size = sizeof(__u64), .align = sizeof(__u64),
 		.get = fpr_get, .set = fpr_set
 	}
 };

 static const struct user_regset_view user_parisc_compat_view = {
 	.name = "parisc", .e_machine = EM_PARISC, .ei_osabi = ELFOSABI_LINUX,
 	.regsets = compat_regsets, .n = ARRAY_SIZE(compat_regsets)
 };
 #endif	/* CONFIG_64BIT */

 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 {
 	BUILD_BUG_ON(sizeof(struct user_regs_struct)/sizeof(long) != ELF_NGREG);
 	BUILD_BUG_ON(sizeof(struct user_fp_struct)/sizeof(__u64) != ELF_NFPREG);
 #ifdef CONFIG_64BIT
 	if (is_compat_task())
 		return &user_parisc_compat_view;
 #endif
 	return &user_parisc_native_view;
 }
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Kernel support for the ptrace() and syscall tracing interfaces.
	*
	* Copyright (C) 2000 Hewlett-Packard Co, Linuxcare Inc.
	* Copyright (C) 2000 Matthew Wilcox <matthew@wil.cx>
	* Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
	* Copyright (C) 2008-2016 Helge Deller <deller@gmx.de>
	*/

	#include <linux/kernel.h>
	#include <linux/sched.h>
	#include <linux/mm.h>
	#include <linux/smp.h>
	#include <linux/elf.h>
	#include <linux/errno.h>
	#include <linux/ptrace.h>
	#include <linux/tracehook.h>
	#include <linux/user.h>
	#include <linux/personality.h>
	#include <linux/regset.h>
	#include <linux/security.h>
	#include <linux/seccomp.h>
	#include <linux/compat.h>
	#include <linux/signal.h>
	#include <linux/audit.h>

	#include <linux/uaccess.h>
	#include <asm/pgtable.h>
	#include <asm/processor.h>
	#include <asm/asm-offsets.h>

	/* PSW bits we allow the debugger to modify */
	#define USER_PSW_BITS (PSW_N \| PSW_B \| PSW_V \| PSW_CB)

	#define CREATE_TRACE_POINTS
	#include <trace/events/syscalls.h>

	/*
	* These are our native regset flavors.
	*/
	enum parisc_regset {
	REGSET_GENERAL,
	REGSET_FP
	};

	/*
	* Called by kernel/ptrace.c when detaching..
	*
	* Make sure single step bits etc are not set.
	*/
	void ptrace_disable(struct task_struct *task)
	{
	clear_tsk_thread_flag(task, TIF_SINGLESTEP);
	clear_tsk_thread_flag(task, TIF_BLOCKSTEP);

	/* make sure the trap bits are not set */
	pa_psw(task)->r = 0;
	pa_psw(task)->t = 0;
	pa_psw(task)->h = 0;
	pa_psw(task)->l = 0;
	}

	/*
	* The following functions are called by ptrace_resume() when
	* enabling or disabling single/block tracing.
	*/
	void user_disable_single_step(struct task_struct *task)
	{
	ptrace_disable(task);
	}

	void user_enable_single_step(struct task_struct *task)
	{
	clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
	set_tsk_thread_flag(task, TIF_SINGLESTEP);

	if (pa_psw(task)->n) {
	struct siginfo si;

	/* Nullified, just crank over the queue. */
	task_regs(task)->iaoq[0] = task_regs(task)->iaoq[1];
	task_regs(task)->iasq[0] = task_regs(task)->iasq[1];
	task_regs(task)->iaoq[1] = task_regs(task)->iaoq[0] + 4;
	pa_psw(task)->n = 0;
	pa_psw(task)->x = 0;
	pa_psw(task)->y = 0;
	pa_psw(task)->z = 0;
	pa_psw(task)->b = 0;
	ptrace_disable(task);
	/* Don't wake up the task, but let the
	parent know something happened. */
	si.si_code = TRAP_TRACE;
	si.si_addr = (void __user *) (task_regs(task)->iaoq[0] & ~3);
	si.si_signo = SIGTRAP;
	si.si_errno = 0;
	force_sig_info(SIGTRAP, &si, task);
	/* notify_parent(task, SIGCHLD); */
	return;
	}

	/* Enable recovery counter traps. The recovery counter
	* itself will be set to zero on a task switch. If the
	* task is suspended on a syscall then the syscall return
	* path will overwrite the recovery counter with a suitable
	* value such that it traps once back in user space. We
	* disable interrupts in the tasks PSW here also, to avoid
	* interrupts while the recovery counter is decrementing.
	*/
	pa_psw(task)->r = 1;
	pa_psw(task)->t = 0;
	pa_psw(task)->h = 0;
	pa_psw(task)->l = 0;
	}

	void user_enable_block_step(struct task_struct *task)
	{
	clear_tsk_thread_flag(task, TIF_SINGLESTEP);
	set_tsk_thread_flag(task, TIF_BLOCKSTEP);

	/* Enable taken branch trap. */
	pa_psw(task)->r = 0;
	pa_psw(task)->t = 1;
	pa_psw(task)->h = 0;
	pa_psw(task)->l = 0;
	}

	long arch_ptrace(struct task_struct *child, long request,
	unsigned long addr, unsigned long data)
	{
	unsigned long __user datap = (unsigned long __user )data;
	unsigned long tmp;
	long ret = -EIO;

	unsigned long user_regs_struct_size = sizeof(struct user_regs_struct);
	#ifdef CONFIG_64BIT
	if (is_compat_task())
	user_regs_struct_size /= 2;
	#endif

	switch (request) {

	/* Read the word at location addr in the USER area. For ptraced
	processes, the kernel saves all regs on a syscall. */
	case PTRACE_PEEKUSR:
	if ((addr & (sizeof(unsigned long)-1)) \|\|
	addr >= sizeof(struct pt_regs))
	break;
	tmp = (unsigned long ) ((char *) task_regs(child) + addr);
	ret = put_user(tmp, datap);
	break;

	/* Write the word at location addr in the USER area. This will need
	to change when the kernel no longer saves all regs on a syscall.
	FIXME. There is a problem at the moment in that r3-r18 are only
	saved if the process is ptraced on syscall entry, and even then
	those values are overwritten by actual register values on syscall
	exit. */
	case PTRACE_POKEUSR:
	/* Some register values written here may be ignored in
	* entry.S:syscall_restore_rfi; e.g. iaoq is written with
	* r31/r31+4, and not with the values in pt_regs.
	*/
	if (addr == PT_PSW) {
	/* Allow writing to Nullify, Divide-step-correction,
	* and carry/borrow bits.
	* BEWARE, if you set N, and then single step, it won't
	* stop on the nullified instruction.
	*/
	data &= USER_PSW_BITS;
	task_regs(child)->gr[0] &= ~USER_PSW_BITS;
	task_regs(child)->gr[0] \|= data;
	ret = 0;
	break;
	}

	if ((addr & (sizeof(unsigned long)-1)) \|\|
	addr >= sizeof(struct pt_regs))
	break;
	if (addr == PT_IAOQ0 \|\| addr == PT_IAOQ1) {
	data \|= 3; /* ensure userspace privilege */
	}
	if ((addr >= PT_GR1 && addr <= PT_GR31) \|\|
	addr == PT_IAOQ0 \|\| addr == PT_IAOQ1 \|\|
	(addr >= PT_FR0 && addr <= PT_FR31 + 4) \|\|
	addr == PT_SAR) {
	(unsigned long ) ((char *) task_regs(child) + addr) = data;
	ret = 0;
	}
	break;

	case PTRACE_GETREGS: /* Get all gp regs from the child. */
	return copy_regset_to_user(child,
	task_user_regset_view(current),
	REGSET_GENERAL,
	0, user_regs_struct_size,
	datap);

	case PTRACE_SETREGS: /* Set all gp regs in the child. */
	return copy_regset_from_user(child,
	task_user_regset_view(current),
	REGSET_GENERAL,
	0, user_regs_struct_size,
	datap);

	case PTRACE_GETFPREGS: /* Get the child FPU state. */
	return copy_regset_to_user(child,
	task_user_regset_view(current),
	REGSET_FP,
	0, sizeof(struct user_fp_struct),
	datap);

	case PTRACE_SETFPREGS: /* Set the child FPU state. */
	return copy_regset_from_user(child,
	task_user_regset_view(current),
	REGSET_FP,
	0, sizeof(struct user_fp_struct),
	datap);

	default:
	ret = ptrace_request(child, request, addr, data);
	break;
	}

	return ret;
	}


	#ifdef CONFIG_COMPAT

	/* This function is needed to translate 32 bit pt_regs offsets in to
	* 64 bit pt_regs offsets. For example, a 32 bit gdb under a 64 bit kernel
	* will request offset 12 if it wants gr3, but the lower 32 bits of
	* the 64 bit kernels view of gr3 will be at offset 28 (3*8 + 4).
	* This code relies on a 32 bit pt_regs being comprised of 32 bit values
	* except for the fp registers which (a) are 64 bits, and (b) follow
	* the gr registers at the start of pt_regs. The 32 bit pt_regs should
	* be half the size of the 64 bit pt_regs, plus 32*4 to allow for fr[]
	* being 64 bit in both cases.
	*/

	static compat_ulong_t translate_usr_offset(compat_ulong_t offset)
	{
	compat_ulong_t pos;

	if (offset < 324) / gr[0..31] */
	pos = offset * 2 + 4;
	else if (offset < 324+328) /* fr[0] ... fr[31] */
	pos = (offset - 32*4) + PT_FR0;
	else if (offset < sizeof(struct pt_regs)/2 + 324) / sr[0] ... ipsw */
	pos = (offset - 324 - 328) * 2 + PT_SR0 + 4;
	else
	pos = sizeof(struct pt_regs);

	return pos;
	}

	long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
	compat_ulong_t addr, compat_ulong_t data)
	{
	compat_uint_t tmp;
	long ret = -EIO;

	switch (request) {

	case PTRACE_PEEKUSR:
	if (addr & (sizeof(compat_uint_t)-1))
	break;
	addr = translate_usr_offset(addr);
	if (addr >= sizeof(struct pt_regs))
	break;

	tmp = (compat_uint_t ) ((char *) task_regs(child) + addr);
	ret = put_user(tmp, (compat_uint_t *) (unsigned long) data);
	break;

	/* Write the word at location addr in the USER area. This will need
	to change when the kernel no longer saves all regs on a syscall.
	FIXME. There is a problem at the moment in that r3-r18 are only
	saved if the process is ptraced on syscall entry, and even then
	those values are overwritten by actual register values on syscall
	exit. */
	case PTRACE_POKEUSR:
	/* Some register values written here may be ignored in
	* entry.S:syscall_restore_rfi; e.g. iaoq is written with
	* r31/r31+4, and not with the values in pt_regs.
	*/
	if (addr == PT_PSW) {
	/* Since PT_PSW==0, it is valid for 32 bit processes
	* under 64 bit kernels as well.
	*/
	ret = arch_ptrace(child, request, addr, data);
	} else {
	if (addr & (sizeof(compat_uint_t)-1))
	break;
	addr = translate_usr_offset(addr);
	if (addr >= sizeof(struct pt_regs))
	break;
	if (addr == PT_IAOQ0+4 \|\| addr == PT_IAOQ1+4) {
	data \|= 3; /* ensure userspace privilege */
	}
	if (addr >= PT_FR0 && addr <= PT_FR31 + 4) {
	/* Special case, fp regs are 64 bits anyway */
	(__u32 ) ((char *) task_regs(child) + addr) = data;
	ret = 0;
	}
	else if ((addr >= PT_GR1+4 && addr <= PT_GR31+4) \|\|
	addr == PT_IAOQ0+4 \|\| addr == PT_IAOQ1+4 \|\|
	addr == PT_SAR+4) {
	/* Zero the top 32 bits */
	(__u32 ) ((char *) task_regs(child) + addr - 4) = 0;
	(__u32 ) ((char *) task_regs(child) + addr) = data;
	ret = 0;
	}
	}
	break;
	case PTRACE_GETREGS:
	case PTRACE_SETREGS:
	case PTRACE_GETFPREGS:
	case PTRACE_SETFPREGS:
	return arch_ptrace(child, request, addr, data);

	default:
	ret = compat_ptrace_request(child, request, addr, data);
	break;
	}

	return ret;
	}
	#endif

	long do_syscall_trace_enter(struct pt_regs *regs)
	{
	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
	int rc = tracehook_report_syscall_entry(regs);

	/*
	* As tracesys_next does not set %r28 to -ENOSYS
	* when %r20 is set to -1, initialize it here.
	*/
	regs->gr[28] = -ENOSYS;

	if (rc) {
	/*
	* A nonzero return code from
	* tracehook_report_syscall_entry() tells us
	* to prevent the syscall execution. Skip
	* the syscall call and the syscall restart handling.
	*
	* Note that the tracer may also just change
	* regs->gr[20] to an invalid syscall number,
	* that is handled by tracesys_next.
	*/
	regs->gr[20] = -1UL;
	return -1;
	}
	}

	/* Do the secure computing check after ptrace. */
	if (secure_computing(NULL) == -1)
	return -1;

	#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
	trace_sys_enter(regs, regs->gr[20]);
	#endif

	#ifdef CONFIG_64BIT
	if (!is_compat_task())
	audit_syscall_entry(regs->gr[20], regs->gr[26], regs->gr[25],
	regs->gr[24], regs->gr[23]);
	else
	#endif
	audit_syscall_entry(regs->gr[20] & 0xffffffff,
	regs->gr[26] & 0xffffffff,
	regs->gr[25] & 0xffffffff,
	regs->gr[24] & 0xffffffff,
	regs->gr[23] & 0xffffffff);

	/*
	* Sign extend the syscall number to 64bit since it may have been
	* modified by a compat ptrace call
	*/
	return (int) ((u32) regs->gr[20]);
	}

	void do_syscall_trace_exit(struct pt_regs *regs)
	{
	int stepping = test_thread_flag(TIF_SINGLESTEP) \|\|
	test_thread_flag(TIF_BLOCKSTEP);

	audit_syscall_exit(regs);

	#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
	trace_sys_exit(regs, regs->gr[20]);
	#endif

	if (stepping \|\| test_thread_flag(TIF_SYSCALL_TRACE))
	tracehook_report_syscall_exit(regs, stepping);
	}


	/*
	* regset functions.
	*/

	static int fpr_get(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	void kbuf, void __user ubuf)
	{
	struct pt_regs *regs = task_regs(target);
	__u64 *k = kbuf;
	__u64 __user *u = ubuf;
	__u64 reg;

	pos /= sizeof(reg);
	count /= sizeof(reg);

	if (kbuf)
	for (; count > 0 && pos < ELF_NFPREG; --count)
	*k++ = regs->fr[pos++];
	else
	for (; count > 0 && pos < ELF_NFPREG; --count)
	if (__put_user(regs->fr[pos++], u++))
	return -EFAULT;

	kbuf = k;
	ubuf = u;
	pos *= sizeof(reg);
	count *= sizeof(reg);
	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
	ELF_NFPREG * sizeof(reg), -1);
	}

	static int fpr_set(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	const void kbuf, const void __user ubuf)
	{
	struct pt_regs *regs = task_regs(target);
	const __u64 *k = kbuf;
	const __u64 __user *u = ubuf;
	__u64 reg;

	pos /= sizeof(reg);
	count /= sizeof(reg);

	if (kbuf)
	for (; count > 0 && pos < ELF_NFPREG; --count)
	regs->fr[pos++] = *k++;
	else
	for (; count > 0 && pos < ELF_NFPREG; --count) {
	if (__get_user(reg, u++))
	return -EFAULT;
	regs->fr[pos++] = reg;
	}

	kbuf = k;
	ubuf = u;
	pos *= sizeof(reg);
	count *= sizeof(reg);
	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
	ELF_NFPREG * sizeof(reg), -1);
	}

	#define RI(reg) (offsetof(struct user_regs_struct,reg) / sizeof(long))

	static unsigned long get_reg(struct pt_regs *regs, int num)
	{
	switch (num) {
	case RI(gr[0]) ... RI(gr[31]): return regs->gr[num - RI(gr[0])];
	case RI(sr[0]) ... RI(sr[7]): return regs->sr[num - RI(sr[0])];
	case RI(iasq[0]): return regs->iasq[0];
	case RI(iasq[1]): return regs->iasq[1];
	case RI(iaoq[0]): return regs->iaoq[0];
	case RI(iaoq[1]): return regs->iaoq[1];
	case RI(sar): return regs->sar;
	case RI(iir): return regs->iir;
	case RI(isr): return regs->isr;
	case RI(ior): return regs->ior;
	case RI(ipsw): return regs->ipsw;
	case RI(cr27): return regs->cr27;
	case RI(cr0): return mfctl(0);
	case RI(cr24): return mfctl(24);
	case RI(cr25): return mfctl(25);
	case RI(cr26): return mfctl(26);
	case RI(cr28): return mfctl(28);
	case RI(cr29): return mfctl(29);
	case RI(cr30): return mfctl(30);
	case RI(cr31): return mfctl(31);
	case RI(cr8): return mfctl(8);
	case RI(cr9): return mfctl(9);
	case RI(cr12): return mfctl(12);
	case RI(cr13): return mfctl(13);
	case RI(cr10): return mfctl(10);
	case RI(cr15): return mfctl(15);
	default: return 0;
	}
	}

	static void set_reg(struct pt_regs *regs, int num, unsigned long val)
	{
	switch (num) {
	case RI(gr[0]): /*
	* PSW is in gr[0].
	* Allow writing to Nullify, Divide-step-correction,
	* and carry/borrow bits.
	* BEWARE, if you set N, and then single step, it won't
	* stop on the nullified instruction.
	*/
	val &= USER_PSW_BITS;
	regs->gr[0] &= ~USER_PSW_BITS;
	regs->gr[0] \|= val;
	return;
	case RI(gr[1]) ... RI(gr[31]):
	regs->gr[num - RI(gr[0])] = val;
	return;
	case RI(iaoq[0]):
	case RI(iaoq[1]):
	/* set 2 lowest bits to ensure userspace privilege: */
	regs->iaoq[num - RI(iaoq[0])] = val \| 3;
	return;
	case RI(sar): regs->sar = val;
	return;
	default: return;
	#if 0
	/* do not allow to change any of the following registers (yet) */
	case RI(sr[0]) ... RI(sr[7]): return regs->sr[num - RI(sr[0])];
	case RI(iasq[0]): return regs->iasq[0];
	case RI(iasq[1]): return regs->iasq[1];
	case RI(iir): return regs->iir;
	case RI(isr): return regs->isr;
	case RI(ior): return regs->ior;
	case RI(ipsw): return regs->ipsw;
	case RI(cr27): return regs->cr27;
	case cr0, cr24, cr25, cr26, cr27, cr28, cr29, cr30, cr31;
	case cr8, cr9, cr12, cr13, cr10, cr15;
	#endif
	}
	}

	static int gpr_get(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	void kbuf, void __user ubuf)
	{
	struct pt_regs *regs = task_regs(target);
	unsigned long *k = kbuf;
	unsigned long __user *u = ubuf;
	unsigned long reg;

	pos /= sizeof(reg);
	count /= sizeof(reg);

	if (kbuf)
	for (; count > 0 && pos < ELF_NGREG; --count)
	*k++ = get_reg(regs, pos++);
	else
	for (; count > 0 && pos < ELF_NGREG; --count)
	if (__put_user(get_reg(regs, pos++), u++))
	return -EFAULT;
	kbuf = k;
	ubuf = u;
	pos *= sizeof(reg);
	count *= sizeof(reg);
	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
	ELF_NGREG * sizeof(reg), -1);
	}

	static int gpr_set(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	const void kbuf, const void __user ubuf)
	{
	struct pt_regs *regs = task_regs(target);
	const unsigned long *k = kbuf;
	const unsigned long __user *u = ubuf;
	unsigned long reg;

	pos /= sizeof(reg);
	count /= sizeof(reg);

	if (kbuf)
	for (; count > 0 && pos < ELF_NGREG; --count)
	set_reg(regs, pos++, *k++);
	else
	for (; count > 0 && pos < ELF_NGREG; --count) {
	if (__get_user(reg, u++))
	return -EFAULT;
	set_reg(regs, pos++, reg);
	}

	kbuf = k;
	ubuf = u;
	pos *= sizeof(reg);
	count *= sizeof(reg);
	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
	ELF_NGREG * sizeof(reg), -1);
	}

	static const struct user_regset native_regsets[] = {
	[REGSET_GENERAL] = {
	.core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
	.size = sizeof(long), .align = sizeof(long),
	.get = gpr_get, .set = gpr_set
	},
	[REGSET_FP] = {
	.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
	.size = sizeof(__u64), .align = sizeof(__u64),
	.get = fpr_get, .set = fpr_set
	}
	};

	static const struct user_regset_view user_parisc_native_view = {
	.name = "parisc", .e_machine = ELF_ARCH, .ei_osabi = ELFOSABI_LINUX,
	.regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
	};

	#ifdef CONFIG_64BIT
	#include <linux/compat.h>

	static int gpr32_get(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	void kbuf, void __user ubuf)
	{
	struct pt_regs *regs = task_regs(target);
	compat_ulong_t *k = kbuf;
	compat_ulong_t __user *u = ubuf;
	compat_ulong_t reg;

	pos /= sizeof(reg);
	count /= sizeof(reg);

	if (kbuf)
	for (; count > 0 && pos < ELF_NGREG; --count)
	*k++ = get_reg(regs, pos++);
	else
	for (; count > 0 && pos < ELF_NGREG; --count)
	if (__put_user((compat_ulong_t) get_reg(regs, pos++), u++))
	return -EFAULT;

	kbuf = k;
	ubuf = u;
	pos *= sizeof(reg);
	count *= sizeof(reg);
	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
	ELF_NGREG * sizeof(reg), -1);
	}

	static int gpr32_set(struct task_struct *target,
	const struct user_regset *regset,
	unsigned int pos, unsigned int count,
	const void kbuf, const void __user ubuf)
	{
	struct pt_regs *regs = task_regs(target);
	const compat_ulong_t *k = kbuf;
	const compat_ulong_t __user *u = ubuf;
	compat_ulong_t reg;

	pos /= sizeof(reg);
	count /= sizeof(reg);

	if (kbuf)
	for (; count > 0 && pos < ELF_NGREG; --count)
	set_reg(regs, pos++, *k++);
	else
	for (; count > 0 && pos < ELF_NGREG; --count) {
	if (__get_user(reg, u++))
	return -EFAULT;
	set_reg(regs, pos++, reg);
	}

	kbuf = k;
	ubuf = u;
	pos *= sizeof(reg);
	count *= sizeof(reg);
	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
	ELF_NGREG * sizeof(reg), -1);
	}

	/*
	* These are the regset flavors matching the 32bit native set.
	*/
	static const struct user_regset compat_regsets[] = {
	[REGSET_GENERAL] = {
	.core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
	.size = sizeof(compat_long_t), .align = sizeof(compat_long_t),
	.get = gpr32_get, .set = gpr32_set
	},
	[REGSET_FP] = {
	.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
	.size = sizeof(__u64), .align = sizeof(__u64),
	.get = fpr_get, .set = fpr_set
	}
	};

	static const struct user_regset_view user_parisc_compat_view = {
	.name = "parisc", .e_machine = EM_PARISC, .ei_osabi = ELFOSABI_LINUX,
	.regsets = compat_regsets, .n = ARRAY_SIZE(compat_regsets)
	};
	#endif /* CONFIG_64BIT */

	const struct user_regset_view task_user_regset_view(struct task_struct task)
	{
	BUILD_BUG_ON(sizeof(struct user_regs_struct)/sizeof(long) != ELF_NGREG);
	BUILD_BUG_ON(sizeof(struct user_fp_struct)/sizeof(__u64) != ELF_NFPREG);
	#ifdef CONFIG_64BIT
	if (is_compat_task())
	return &user_parisc_compat_view;
	#endif
	return &user_parisc_native_view;
	}