summaryrefslogtreecommitdiffstats
path: root/arch/parisc/kernel/ptrace.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/parisc/kernel/ptrace.c')
-rw-r--r--arch/parisc/kernel/ptrace.c790
1 files changed, 790 insertions, 0 deletions
diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c
new file mode 100644
index 000000000..9af11abee
--- /dev/null
+++ b/arch/parisc/kernel/ptrace.c
@@ -0,0 +1,790 @@
+// 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/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/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) {
+ /* 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. */
+ force_sig_fault_to_task(SIGTRAP, TRAP_TRACE,
+ (void __user *) (task_regs(task)->iaoq[0] & ~3),
+ 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 |= PRIV_USER; /* 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 |= PRIV_USER; /* 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 = ptrace_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
+ * ptrace_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() == -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))
+ ptrace_report_syscall_exit(regs, stepping);
+}
+
+
+/*
+ * regset functions.
+ */
+
+static int fpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct pt_regs *regs = task_regs(target);
+
+ return membuf_write(&to, regs->fr, ELF_NFPREG * sizeof(__u64));
+}
+
+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 | PRIV_USER;
+ 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,
+ struct membuf to)
+{
+ struct pt_regs *regs = task_regs(target);
+ unsigned int pos;
+
+ for (pos = 0; pos < ELF_NGREG; pos++)
+ membuf_store(&to, get_reg(regs, pos));
+ return 0;
+}
+
+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),
+ .regset_get = gpr_get, .set = gpr_set
+ },
+ [REGSET_FP] = {
+ .core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
+ .size = sizeof(__u64), .align = sizeof(__u64),
+ .regset_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
+static int gpr32_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct pt_regs *regs = task_regs(target);
+ unsigned int pos;
+
+ for (pos = 0; pos < ELF_NGREG; pos++)
+ membuf_store(&to, (compat_ulong_t)get_reg(regs, pos));
+
+ return 0;
+}
+
+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),
+ .regset_get = gpr32_get, .set = gpr32_set
+ },
+ [REGSET_FP] = {
+ .core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
+ .size = sizeof(__u64), .align = sizeof(__u64),
+ .regset_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;
+}
+
+
+/* HAVE_REGS_AND_STACK_ACCESS_API feature */
+
+struct pt_regs_offset {
+ const char *name;
+ int offset;
+};
+
+#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
+#define REG_OFFSET_INDEX(r,i) {.name = #r#i, .offset = offsetof(struct pt_regs, r[i])}
+#define REG_OFFSET_END {.name = NULL, .offset = 0}
+
+static const struct pt_regs_offset regoffset_table[] = {
+ REG_OFFSET_INDEX(gr,0),
+ REG_OFFSET_INDEX(gr,1),
+ REG_OFFSET_INDEX(gr,2),
+ REG_OFFSET_INDEX(gr,3),
+ REG_OFFSET_INDEX(gr,4),
+ REG_OFFSET_INDEX(gr,5),
+ REG_OFFSET_INDEX(gr,6),
+ REG_OFFSET_INDEX(gr,7),
+ REG_OFFSET_INDEX(gr,8),
+ REG_OFFSET_INDEX(gr,9),
+ REG_OFFSET_INDEX(gr,10),
+ REG_OFFSET_INDEX(gr,11),
+ REG_OFFSET_INDEX(gr,12),
+ REG_OFFSET_INDEX(gr,13),
+ REG_OFFSET_INDEX(gr,14),
+ REG_OFFSET_INDEX(gr,15),
+ REG_OFFSET_INDEX(gr,16),
+ REG_OFFSET_INDEX(gr,17),
+ REG_OFFSET_INDEX(gr,18),
+ REG_OFFSET_INDEX(gr,19),
+ REG_OFFSET_INDEX(gr,20),
+ REG_OFFSET_INDEX(gr,21),
+ REG_OFFSET_INDEX(gr,22),
+ REG_OFFSET_INDEX(gr,23),
+ REG_OFFSET_INDEX(gr,24),
+ REG_OFFSET_INDEX(gr,25),
+ REG_OFFSET_INDEX(gr,26),
+ REG_OFFSET_INDEX(gr,27),
+ REG_OFFSET_INDEX(gr,28),
+ REG_OFFSET_INDEX(gr,29),
+ REG_OFFSET_INDEX(gr,30),
+ REG_OFFSET_INDEX(gr,31),
+ REG_OFFSET_INDEX(sr,0),
+ REG_OFFSET_INDEX(sr,1),
+ REG_OFFSET_INDEX(sr,2),
+ REG_OFFSET_INDEX(sr,3),
+ REG_OFFSET_INDEX(sr,4),
+ REG_OFFSET_INDEX(sr,5),
+ REG_OFFSET_INDEX(sr,6),
+ REG_OFFSET_INDEX(sr,7),
+ REG_OFFSET_INDEX(iasq,0),
+ REG_OFFSET_INDEX(iasq,1),
+ REG_OFFSET_INDEX(iaoq,0),
+ REG_OFFSET_INDEX(iaoq,1),
+ REG_OFFSET_NAME(cr27),
+ REG_OFFSET_NAME(ksp),
+ REG_OFFSET_NAME(kpc),
+ REG_OFFSET_NAME(sar),
+ REG_OFFSET_NAME(iir),
+ REG_OFFSET_NAME(isr),
+ REG_OFFSET_NAME(ior),
+ REG_OFFSET_NAME(ipsw),
+ REG_OFFSET_END,
+};
+
+/**
+ * regs_query_register_offset() - query register offset from its name
+ * @name: the name of a register
+ *
+ * regs_query_register_offset() returns the offset of a register in struct
+ * pt_regs from its name. If the name is invalid, this returns -EINVAL;
+ */
+int regs_query_register_offset(const char *name)
+{
+ const struct pt_regs_offset *roff;
+ for (roff = regoffset_table; roff->name != NULL; roff++)
+ if (!strcmp(roff->name, name))
+ return roff->offset;
+ return -EINVAL;
+}
+
+/**
+ * regs_query_register_name() - query register name from its offset
+ * @offset: the offset of a register in struct pt_regs.
+ *
+ * regs_query_register_name() returns the name of a register from its
+ * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
+ */
+const char *regs_query_register_name(unsigned int offset)
+{
+ const struct pt_regs_offset *roff;
+ for (roff = regoffset_table; roff->name != NULL; roff++)
+ if (roff->offset == offset)
+ return roff->name;
+ return NULL;
+}
+
+/**
+ * regs_within_kernel_stack() - check the address in the stack
+ * @regs: pt_regs which contains kernel stack pointer.
+ * @addr: address which is checked.
+ *
+ * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
+ * If @addr is within the kernel stack, it returns true. If not, returns false.
+ */
+int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
+{
+ return ((addr & ~(THREAD_SIZE - 1)) ==
+ (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
+}
+
+/**
+ * regs_get_kernel_stack_nth() - get Nth entry of the stack
+ * @regs: pt_regs which contains kernel stack pointer.
+ * @n: stack entry number.
+ *
+ * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
+ * is specified by @regs. If the @n th entry is NOT in the kernel stack,
+ * this returns 0.
+ */
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
+{
+ unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
+
+ addr -= n;
+
+ if (!regs_within_kernel_stack(regs, (unsigned long)addr))
+ return 0;
+
+ return *addr;
+}