Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1382 insertions, 0 deletions

diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
new file mode 100644
index 000000000..db7c5be1d
--- /dev/null
+++ b/arch/mips/kernel/ptrace.c
@@ -0,0 +1,1382 @@
+/*
+ * 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.
+ *
+ * Copyright (C) 1992 Ross Biro
+ * Copyright (C) Linus Torvalds
+ * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
+ * Copyright (C) 1996 David S. Miller
+ * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 1999 MIPS Technologies, Inc.
+ * Copyright (C) 2000 Ulf Carlsson
+ *
+ * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
+ * binaries.
+ */
+#include <linux/compiler.h>
+#include <linux/context_tracking.h>
+#include <linux/elf.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/regset.h>
+#include <linux/smp.h>
+#include <linux/security.h>
+#include <linux/stddef.h>
+#include <linux/tracehook.h>
+#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/ftrace.h>
+
+#include <asm/byteorder.h>
+#include <asm/cpu.h>
+#include <asm/cpu-info.h>
+#include <asm/dsp.h>
+#include <asm/fpu.h>
+#include <asm/mipsregs.h>
+#include <asm/mipsmtregs.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+#include <asm/syscall.h>
+#include <linux/uaccess.h>
+#include <asm/bootinfo.h>
+#include <asm/reg.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure single step bits etc are not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+	/* Don't load the watchpoint registers for the ex-child. */
+	clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
+}
+
+/*
+ * 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, struct user_pt_regs __user *data)
+{
+	struct pt_regs *regs;
+	int i;
+
+	if (!access_ok(data, 38 * 8))
+		return -EIO;
+
+	regs = task_pt_regs(child);
+
+	for (i = 0; i < 32; i++)
+		__put_user((long)regs->regs[i], (__s64 __user *)&data->regs[i]);
+	__put_user((long)regs->lo, (__s64 __user *)&data->lo);
+	__put_user((long)regs->hi, (__s64 __user *)&data->hi);
+	__put_user((long)regs->cp0_epc, (__s64 __user *)&data->cp0_epc);
+	__put_user((long)regs->cp0_badvaddr, (__s64 __user *)&data->cp0_badvaddr);
+	__put_user((long)regs->cp0_status, (__s64 __user *)&data->cp0_status);
+	__put_user((long)regs->cp0_cause, (__s64 __user *)&data->cp0_cause);
+
+	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, struct user_pt_regs __user *data)
+{
+	struct pt_regs *regs;
+	int i;
+
+	if (!access_ok(data, 38 * 8))
+		return -EIO;
+
+	regs = task_pt_regs(child);
+
+	for (i = 0; i < 32; i++)
+		__get_user(regs->regs[i], (__s64 __user *)&data->regs[i]);
+	__get_user(regs->lo, (__s64 __user *)&data->lo);
+	__get_user(regs->hi, (__s64 __user *)&data->hi);
+	__get_user(regs->cp0_epc, (__s64 __user *)&data->cp0_epc);
+
+	/* badvaddr, status, and cause may not be written.  */
+
+	/* System call number may have been changed */
+	mips_syscall_update_nr(child, regs);
+
+	return 0;
+}
+
+int ptrace_get_watch_regs(struct task_struct *child,
+			  struct pt_watch_regs __user *addr)
+{
+	enum pt_watch_style style;
+	int i;
+
+	if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
+		return -EIO;
+	if (!access_ok(addr, sizeof(struct pt_watch_regs)))
+		return -EIO;
+
+#ifdef CONFIG_32BIT
+	style = pt_watch_style_mips32;
+#define WATCH_STYLE mips32
+#else
+	style = pt_watch_style_mips64;
+#define WATCH_STYLE mips64
+#endif
+
+	__put_user(style, &addr->style);
+	__put_user(boot_cpu_data.watch_reg_use_cnt,
+		   &addr->WATCH_STYLE.num_valid);
+	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
+		__put_user(child->thread.watch.mips3264.watchlo[i],
+			   &addr->WATCH_STYLE.watchlo[i]);
+		__put_user(child->thread.watch.mips3264.watchhi[i] &
+				(MIPS_WATCHHI_MASK | MIPS_WATCHHI_IRW),
+			   &addr->WATCH_STYLE.watchhi[i]);
+		__put_user(boot_cpu_data.watch_reg_masks[i],
+			   &addr->WATCH_STYLE.watch_masks[i]);
+	}
+	for (; i < 8; i++) {
+		__put_user(0, &addr->WATCH_STYLE.watchlo[i]);
+		__put_user(0, &addr->WATCH_STYLE.watchhi[i]);
+		__put_user(0, &addr->WATCH_STYLE.watch_masks[i]);
+	}
+
+	return 0;
+}
+
+int ptrace_set_watch_regs(struct task_struct *child,
+			  struct pt_watch_regs __user *addr)
+{
+	int i;
+	int watch_active = 0;
+	unsigned long lt[NUM_WATCH_REGS];
+	u16 ht[NUM_WATCH_REGS];
+
+	if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
+		return -EIO;
+	if (!access_ok(addr, sizeof(struct pt_watch_regs)))
+		return -EIO;
+	/* Check the values. */
+	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
+		__get_user(lt[i], &addr->WATCH_STYLE.watchlo[i]);
+#ifdef CONFIG_32BIT
+		if (lt[i] & __UA_LIMIT)
+			return -EINVAL;
+#else
+		if (test_tsk_thread_flag(child, TIF_32BIT_ADDR)) {
+			if (lt[i] & 0xffffffff80000000UL)
+				return -EINVAL;
+		} else {
+			if (lt[i] & __UA_LIMIT)
+				return -EINVAL;
+		}
+#endif
+		__get_user(ht[i], &addr->WATCH_STYLE.watchhi[i]);
+		if (ht[i] & ~MIPS_WATCHHI_MASK)
+			return -EINVAL;
+	}
+	/* Install them. */
+	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
+		if (lt[i] & MIPS_WATCHLO_IRW)
+			watch_active = 1;
+		child->thread.watch.mips3264.watchlo[i] = lt[i];
+		/* Set the G bit. */
+		child->thread.watch.mips3264.watchhi[i] = ht[i];
+	}
+
+	if (watch_active)
+		set_tsk_thread_flag(child, TIF_LOAD_WATCH);
+	else
+		clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
+
+	return 0;
+}
+
+/* regset get/set implementations */
+
+#if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
+
+static int gpr32_get(struct task_struct *target,
+		     const struct user_regset *regset,
+		     struct membuf to)
+{
+	struct pt_regs *regs = task_pt_regs(target);
+	u32 uregs[ELF_NGREG] = {};
+
+	mips_dump_regs32(uregs, regs);
+	return membuf_write(&to, uregs, sizeof(uregs));
+}
+
+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_pt_regs(target);
+	u32 uregs[ELF_NGREG];
+	unsigned start, num_regs, i;
+	int err;
+
+	start = pos / sizeof(u32);
+	num_regs = count / sizeof(u32);
+
+	if (start + num_regs > ELF_NGREG)
+		return -EIO;
+
+	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
+				 sizeof(uregs));
+	if (err)
+		return err;
+
+	for (i = start; i < num_regs; i++) {
+		/*
+		 * Cast all values to signed here so that if this is a 64-bit
+		 * kernel, the supplied 32-bit values will be sign extended.
+		 */
+		switch (i) {
+		case MIPS32_EF_R1 ... MIPS32_EF_R25:
+			/* k0/k1 are ignored. */
+		case MIPS32_EF_R28 ... MIPS32_EF_R31:
+			regs->regs[i - MIPS32_EF_R0] = (s32)uregs[i];
+			break;
+		case MIPS32_EF_LO:
+			regs->lo = (s32)uregs[i];
+			break;
+		case MIPS32_EF_HI:
+			regs->hi = (s32)uregs[i];
+			break;
+		case MIPS32_EF_CP0_EPC:
+			regs->cp0_epc = (s32)uregs[i];
+			break;
+		}
+	}
+
+	/* System call number may have been changed */
+	mips_syscall_update_nr(target, regs);
+
+	return 0;
+}
+
+#endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
+
+#ifdef CONFIG_64BIT
+
+static int gpr64_get(struct task_struct *target,
+		     const struct user_regset *regset,
+		     struct membuf to)
+{
+	struct pt_regs *regs = task_pt_regs(target);
+	u64 uregs[ELF_NGREG] = {};
+
+	mips_dump_regs64(uregs, regs);
+	return membuf_write(&to, uregs, sizeof(uregs));
+}
+
+static int gpr64_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_pt_regs(target);
+	u64 uregs[ELF_NGREG];
+	unsigned start, num_regs, i;
+	int err;
+
+	start = pos / sizeof(u64);
+	num_regs = count / sizeof(u64);
+
+	if (start + num_regs > ELF_NGREG)
+		return -EIO;
+
+	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
+				 sizeof(uregs));
+	if (err)
+		return err;
+
+	for (i = start; i < num_regs; i++) {
+		switch (i) {
+		case MIPS64_EF_R1 ... MIPS64_EF_R25:
+			/* k0/k1 are ignored. */
+		case MIPS64_EF_R28 ... MIPS64_EF_R31:
+			regs->regs[i - MIPS64_EF_R0] = uregs[i];
+			break;
+		case MIPS64_EF_LO:
+			regs->lo = uregs[i];
+			break;
+		case MIPS64_EF_HI:
+			regs->hi = uregs[i];
+			break;
+		case MIPS64_EF_CP0_EPC:
+			regs->cp0_epc = uregs[i];
+			break;
+		}
+	}
+
+	/* System call number may have been changed */
+	mips_syscall_update_nr(target, regs);
+
+	return 0;
+}
+
+#endif /* CONFIG_64BIT */
+
+
+#ifdef CONFIG_MIPS_FP_SUPPORT
+
+/*
+ * Poke at FCSR according to its mask.  Set the Cause bits even
+ * if a corresponding Enable bit is set.  This will be noticed at
+ * the time the thread is switched to and SIGFPE thrown accordingly.
+ */
+static void ptrace_setfcr31(struct task_struct *child, u32 value)
+{
+	u32 fcr31;
+	u32 mask;
+
+	fcr31 = child->thread.fpu.fcr31;
+	mask = boot_cpu_data.fpu_msk31;
+	child->thread.fpu.fcr31 = (value & ~mask) | (fcr31 & mask);
+}
+
+int ptrace_getfpregs(struct task_struct *child, __u32 __user *data)
+{
+	int i;
+
+	if (!access_ok(data, 33 * 8))
+		return -EIO;
+
+	if (tsk_used_math(child)) {
+		union fpureg *fregs = get_fpu_regs(child);
+		for (i = 0; i < 32; i++)
+			__put_user(get_fpr64(&fregs[i], 0),
+				   i + (__u64 __user *)data);
+	} else {
+		for (i = 0; i < 32; i++)
+			__put_user((__u64) -1, i + (__u64 __user *) data);
+	}
+
+	__put_user(child->thread.fpu.fcr31, data + 64);
+	__put_user(boot_cpu_data.fpu_id, data + 65);
+
+	return 0;
+}
+
+int ptrace_setfpregs(struct task_struct *child, __u32 __user *data)
+{
+	union fpureg *fregs;
+	u64 fpr_val;
+	u32 value;
+	int i;
+
+	if (!access_ok(data, 33 * 8))
+		return -EIO;
+
+	init_fp_ctx(child);
+	fregs = get_fpu_regs(child);
+
+	for (i = 0; i < 32; i++) {
+		__get_user(fpr_val, i + (__u64 __user *)data);
+		set_fpr64(&fregs[i], 0, fpr_val);
+	}
+
+	__get_user(value, data + 64);
+	ptrace_setfcr31(child, value);
+
+	/* FIR may not be written.  */
+
+	return 0;
+}
+
+/*
+ * Copy the floating-point context to the supplied NT_PRFPREG buffer,
+ * !CONFIG_CPU_HAS_MSA variant.  FP context's general register slots
+ * correspond 1:1 to buffer slots.  Only general registers are copied.
+ */
+static void fpr_get_fpa(struct task_struct *target,
+		       struct membuf *to)
+{
+	membuf_write(to, &target->thread.fpu,
+			NUM_FPU_REGS * sizeof(elf_fpreg_t));
+}
+
+/*
+ * Copy the floating-point context to the supplied NT_PRFPREG buffer,
+ * CONFIG_CPU_HAS_MSA variant.  Only lower 64 bits of FP context's
+ * general register slots are copied to buffer slots.  Only general
+ * registers are copied.
+ */
+static void fpr_get_msa(struct task_struct *target, struct membuf *to)
+{
+	unsigned int i;
+
+	BUILD_BUG_ON(sizeof(u64) != sizeof(elf_fpreg_t));
+	for (i = 0; i < NUM_FPU_REGS; i++)
+		membuf_store(to, get_fpr64(&target->thread.fpu.fpr[i], 0));
+}
+
+/*
+ * Copy the floating-point context to the supplied NT_PRFPREG buffer.
+ * Choose the appropriate helper for general registers, and then copy
+ * the FCSR and FIR registers separately.
+ */
+static int fpr_get(struct task_struct *target,
+		   const struct user_regset *regset,
+		   struct membuf to)
+{
+	if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
+		fpr_get_fpa(target, &to);
+	else
+		fpr_get_msa(target, &to);
+
+	membuf_write(&to, &target->thread.fpu.fcr31, sizeof(u32));
+	membuf_write(&to, &boot_cpu_data.fpu_id, sizeof(u32));
+	return 0;
+}
+
+/*
+ * Copy the supplied NT_PRFPREG buffer to the floating-point context,
+ * !CONFIG_CPU_HAS_MSA variant.   Buffer slots correspond 1:1 to FP
+ * context's general register slots.  Only general registers are copied.
+ */
+static int fpr_set_fpa(struct task_struct *target,
+		       unsigned int *pos, unsigned int *count,
+		       const void **kbuf, const void __user **ubuf)
+{
+	return user_regset_copyin(pos, count, kbuf, ubuf,
+				  &target->thread.fpu,
+				  0, NUM_FPU_REGS * sizeof(elf_fpreg_t));
+}
+
+/*
+ * Copy the supplied NT_PRFPREG buffer to the floating-point context,
+ * CONFIG_CPU_HAS_MSA variant.  Buffer slots are copied to lower 64
+ * bits only of FP context's general register slots.  Only general
+ * registers are copied.
+ */
+static int fpr_set_msa(struct task_struct *target,
+		       unsigned int *pos, unsigned int *count,
+		       const void **kbuf, const void __user **ubuf)
+{
+	unsigned int i;
+	u64 fpr_val;
+	int err;
+
+	BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
+	for (i = 0; i < NUM_FPU_REGS && *count > 0; i++) {
+		err = user_regset_copyin(pos, count, kbuf, ubuf,
+					 &fpr_val, i * sizeof(elf_fpreg_t),
+					 (i + 1) * sizeof(elf_fpreg_t));
+		if (err)
+			return err;
+		set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
+	}
+
+	return 0;
+}
+
+/*
+ * Copy the supplied NT_PRFPREG buffer to the floating-point context.
+ * Choose the appropriate helper for general registers, and then copy
+ * the FCSR register separately.  Ignore the incoming FIR register
+ * contents though, as the register is read-only.
+ *
+ * We optimize for the case where `count % sizeof(elf_fpreg_t) == 0',
+ * which is supposed to have been guaranteed by the kernel before
+ * calling us, e.g. in `ptrace_regset'.  We enforce that requirement,
+ * so that we can safely avoid preinitializing temporaries for
+ * partial register writes.
+ */
+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)
+{
+	const int fcr31_pos = NUM_FPU_REGS * sizeof(elf_fpreg_t);
+	const int fir_pos = fcr31_pos + sizeof(u32);
+	u32 fcr31;
+	int err;
+
+	BUG_ON(count % sizeof(elf_fpreg_t));
+
+	if (pos + count > sizeof(elf_fpregset_t))
+		return -EIO;
+
+	init_fp_ctx(target);
+
+	if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
+		err = fpr_set_fpa(target, &pos, &count, &kbuf, &ubuf);
+	else
+		err = fpr_set_msa(target, &pos, &count, &kbuf, &ubuf);
+	if (err)
+		return err;
+
+	if (count > 0) {
+		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+					 &fcr31,
+					 fcr31_pos, fcr31_pos + sizeof(u32));
+		if (err)
+			return err;
+
+		ptrace_setfcr31(target, fcr31);
+	}
+
+	if (count > 0)
+		err = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+						fir_pos,
+						fir_pos + sizeof(u32));
+
+	return err;
+}
+
+/* Copy the FP mode setting to the supplied NT_MIPS_FP_MODE buffer.  */
+static int fp_mode_get(struct task_struct *target,
+		       const struct user_regset *regset,
+		       struct membuf to)
+{
+	return membuf_store(&to, (int)mips_get_process_fp_mode(target));
+}
+
+/*
+ * Copy the supplied NT_MIPS_FP_MODE buffer to the FP mode setting.
+ *
+ * We optimize for the case where `count % sizeof(int) == 0', which
+ * is supposed to have been guaranteed by the kernel before calling
+ * us, e.g. in `ptrace_regset'.  We enforce that requirement, so
+ * that we can safely avoid preinitializing temporaries for partial
+ * mode writes.
+ */
+static int fp_mode_set(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       const void *kbuf, const void __user *ubuf)
+{
+	int fp_mode;
+	int err;
+
+	BUG_ON(count % sizeof(int));
+
+	if (pos + count > sizeof(fp_mode))
+		return -EIO;
+
+	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fp_mode, 0,
+				 sizeof(fp_mode));
+	if (err)
+		return err;
+
+	if (count > 0)
+		err = mips_set_process_fp_mode(target, fp_mode);
+
+	return err;
+}
+
+#endif /* CONFIG_MIPS_FP_SUPPORT */
+
+#ifdef CONFIG_CPU_HAS_MSA
+
+struct msa_control_regs {
+	unsigned int fir;
+	unsigned int fcsr;
+	unsigned int msair;
+	unsigned int msacsr;
+};
+
+static void copy_pad_fprs(struct task_struct *target,
+			 const struct user_regset *regset,
+			 struct membuf *to,
+			 unsigned int live_sz)
+{
+	int i, j;
+	unsigned long long fill = ~0ull;
+	unsigned int cp_sz, pad_sz;
+
+	cp_sz = min(regset->size, live_sz);
+	pad_sz = regset->size - cp_sz;
+	WARN_ON(pad_sz % sizeof(fill));
+
+	for (i = 0; i < NUM_FPU_REGS; i++) {
+		membuf_write(to, &target->thread.fpu.fpr[i], cp_sz);
+		for (j = 0; j < (pad_sz / sizeof(fill)); j++)
+			membuf_store(to, fill);
+	}
+}
+
+static int msa_get(struct task_struct *target,
+		   const struct user_regset *regset,
+		   struct membuf to)
+{
+	const unsigned int wr_size = NUM_FPU_REGS * regset->size;
+	const struct msa_control_regs ctrl_regs = {
+		.fir = boot_cpu_data.fpu_id,
+		.fcsr = target->thread.fpu.fcr31,
+		.msair = boot_cpu_data.msa_id,
+		.msacsr = target->thread.fpu.msacsr,
+	};
+
+	if (!tsk_used_math(target)) {
+		/* The task hasn't used FP or MSA, fill with 0xff */
+		copy_pad_fprs(target, regset, &to, 0);
+	} else if (!test_tsk_thread_flag(target, TIF_MSA_CTX_LIVE)) {
+		/* Copy scalar FP context, fill the rest with 0xff */
+		copy_pad_fprs(target, regset, &to, 8);
+	} else if (sizeof(target->thread.fpu.fpr[0]) == regset->size) {
+		/* Trivially copy the vector registers */
+		membuf_write(&to, &target->thread.fpu.fpr, wr_size);
+	} else {
+		/* Copy as much context as possible, fill the rest with 0xff */
+		copy_pad_fprs(target, regset, &to,
+				sizeof(target->thread.fpu.fpr[0]));
+	}
+
+	return membuf_write(&to, &ctrl_regs, sizeof(ctrl_regs));
+}
+
+static int msa_set(struct task_struct *target,
+		   const struct user_regset *regset,
+		   unsigned int pos, unsigned int count,
+		   const void *kbuf, const void __user *ubuf)
+{
+	const unsigned int wr_size = NUM_FPU_REGS * regset->size;
+	struct msa_control_regs ctrl_regs;
+	unsigned int cp_sz;
+	int i, err, start;
+
+	init_fp_ctx(target);
+
+	if (sizeof(target->thread.fpu.fpr[0]) == regset->size) {
+		/* Trivially copy the vector registers */
+		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+					 &target->thread.fpu.fpr,
+					 0, wr_size);
+	} else {
+		/* Copy as much context as possible */
+		cp_sz = min_t(unsigned int, regset->size,
+			      sizeof(target->thread.fpu.fpr[0]));
+
+		i = start = err = 0;
+		for (; i < NUM_FPU_REGS; i++, start += regset->size) {
+			err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+						  &target->thread.fpu.fpr[i],
+						  start, start + cp_sz);
+		}
+	}
+
+	if (!err)
+		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl_regs,
+					 wr_size, wr_size + sizeof(ctrl_regs));
+	if (!err) {
+		target->thread.fpu.fcr31 = ctrl_regs.fcsr & ~FPU_CSR_ALL_X;
+		target->thread.fpu.msacsr = ctrl_regs.msacsr & ~MSA_CSR_CAUSEF;
+	}
+
+	return err;
+}
+
+#endif /* CONFIG_CPU_HAS_MSA */
+
+#if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
+
+/*
+ * Copy the DSP context to the supplied 32-bit NT_MIPS_DSP buffer.
+ */
+static int dsp32_get(struct task_struct *target,
+		     const struct user_regset *regset,
+		     struct membuf to)
+{
+	u32 dspregs[NUM_DSP_REGS + 1];
+	unsigned int i;
+
+	BUG_ON(to.left % sizeof(u32));
+
+	if (!cpu_has_dsp)
+		return -EIO;
+
+	for (i = 0; i < NUM_DSP_REGS; i++)
+		dspregs[i] = target->thread.dsp.dspr[i];
+	dspregs[NUM_DSP_REGS] = target->thread.dsp.dspcontrol;
+	return membuf_write(&to, dspregs, sizeof(dspregs));
+}
+
+/*
+ * Copy the supplied 32-bit NT_MIPS_DSP buffer to the DSP context.
+ */
+static int dsp32_set(struct task_struct *target,
+		     const struct user_regset *regset,
+		     unsigned int pos, unsigned int count,
+		     const void *kbuf, const void __user *ubuf)
+{
+	unsigned int start, num_regs, i;
+	u32 dspregs[NUM_DSP_REGS + 1];
+	int err;
+
+	BUG_ON(count % sizeof(u32));
+
+	if (!cpu_has_dsp)
+		return -EIO;
+
+	start = pos / sizeof(u32);
+	num_regs = count / sizeof(u32);
+
+	if (start + num_regs > NUM_DSP_REGS + 1)
+		return -EIO;
+
+	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, dspregs, 0,
+				 sizeof(dspregs));
+	if (err)
+		return err;
+
+	for (i = start; i < num_regs; i++)
+		switch (i) {
+		case 0 ... NUM_DSP_REGS - 1:
+			target->thread.dsp.dspr[i] = (s32)dspregs[i];
+			break;
+		case NUM_DSP_REGS:
+			target->thread.dsp.dspcontrol = (s32)dspregs[i];
+			break;
+		}
+
+	return 0;
+}
+
+#endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
+
+#ifdef CONFIG_64BIT
+
+/*
+ * Copy the DSP context to the supplied 64-bit NT_MIPS_DSP buffer.
+ */
+static int dsp64_get(struct task_struct *target,
+		     const struct user_regset *regset,
+		     struct membuf to)
+{
+	u64 dspregs[NUM_DSP_REGS + 1];
+	unsigned int i;
+
+	BUG_ON(to.left % sizeof(u64));
+
+	if (!cpu_has_dsp)
+		return -EIO;
+
+	for (i = 0; i < NUM_DSP_REGS; i++)
+		dspregs[i] = target->thread.dsp.dspr[i];
+	dspregs[NUM_DSP_REGS] = target->thread.dsp.dspcontrol;
+	return membuf_write(&to, dspregs, sizeof(dspregs));
+}
+
+/*
+ * Copy the supplied 64-bit NT_MIPS_DSP buffer to the DSP context.
+ */
+static int dsp64_set(struct task_struct *target,
+		     const struct user_regset *regset,
+		     unsigned int pos, unsigned int count,
+		     const void *kbuf, const void __user *ubuf)
+{
+	unsigned int start, num_regs, i;
+	u64 dspregs[NUM_DSP_REGS + 1];
+	int err;
+
+	BUG_ON(count % sizeof(u64));
+
+	if (!cpu_has_dsp)
+		return -EIO;
+
+	start = pos / sizeof(u64);
+	num_regs = count / sizeof(u64);
+
+	if (start + num_regs > NUM_DSP_REGS + 1)
+		return -EIO;
+
+	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, dspregs, 0,
+				 sizeof(dspregs));
+	if (err)
+		return err;
+
+	for (i = start; i < num_regs; i++)
+		switch (i) {
+		case 0 ... NUM_DSP_REGS - 1:
+			target->thread.dsp.dspr[i] = dspregs[i];
+			break;
+		case NUM_DSP_REGS:
+			target->thread.dsp.dspcontrol = dspregs[i];
+			break;
+		}
+
+	return 0;
+}
+
+#endif /* CONFIG_64BIT */
+
+/*
+ * Determine whether the DSP context is present.
+ */
+static int dsp_active(struct task_struct *target,
+		      const struct user_regset *regset)
+{
+	return cpu_has_dsp ? NUM_DSP_REGS + 1 : -ENODEV;
+}
+
+enum mips_regset {
+	REGSET_GPR,
+	REGSET_DSP,
+#ifdef CONFIG_MIPS_FP_SUPPORT
+	REGSET_FPR,
+	REGSET_FP_MODE,
+#endif
+#ifdef CONFIG_CPU_HAS_MSA
+	REGSET_MSA,
+#endif
+};
+
+struct pt_regs_offset {
+	const char *name;
+	int offset;
+};
+
+#define REG_OFFSET_NAME(reg, r) {					\
+	.name = #reg,							\
+	.offset = offsetof(struct pt_regs, r)				\
+}
+
+#define REG_OFFSET_END {						\
+	.name = NULL,							\
+	.offset = 0							\
+}
+
+static const struct pt_regs_offset regoffset_table[] = {
+	REG_OFFSET_NAME(r0, regs[0]),
+	REG_OFFSET_NAME(r1, regs[1]),
+	REG_OFFSET_NAME(r2, regs[2]),
+	REG_OFFSET_NAME(r3, regs[3]),
+	REG_OFFSET_NAME(r4, regs[4]),
+	REG_OFFSET_NAME(r5, regs[5]),
+	REG_OFFSET_NAME(r6, regs[6]),
+	REG_OFFSET_NAME(r7, regs[7]),
+	REG_OFFSET_NAME(r8, regs[8]),
+	REG_OFFSET_NAME(r9, regs[9]),
+	REG_OFFSET_NAME(r10, regs[10]),
+	REG_OFFSET_NAME(r11, regs[11]),
+	REG_OFFSET_NAME(r12, regs[12]),
+	REG_OFFSET_NAME(r13, regs[13]),
+	REG_OFFSET_NAME(r14, regs[14]),
+	REG_OFFSET_NAME(r15, regs[15]),
+	REG_OFFSET_NAME(r16, regs[16]),
+	REG_OFFSET_NAME(r17, regs[17]),
+	REG_OFFSET_NAME(r18, regs[18]),
+	REG_OFFSET_NAME(r19, regs[19]),
+	REG_OFFSET_NAME(r20, regs[20]),
+	REG_OFFSET_NAME(r21, regs[21]),
+	REG_OFFSET_NAME(r22, regs[22]),
+	REG_OFFSET_NAME(r23, regs[23]),
+	REG_OFFSET_NAME(r24, regs[24]),
+	REG_OFFSET_NAME(r25, regs[25]),
+	REG_OFFSET_NAME(r26, regs[26]),
+	REG_OFFSET_NAME(r27, regs[27]),
+	REG_OFFSET_NAME(r28, regs[28]),
+	REG_OFFSET_NAME(r29, regs[29]),
+	REG_OFFSET_NAME(r30, regs[30]),
+	REG_OFFSET_NAME(r31, regs[31]),
+	REG_OFFSET_NAME(c0_status, cp0_status),
+	REG_OFFSET_NAME(hi, hi),
+	REG_OFFSET_NAME(lo, lo),
+#ifdef CONFIG_CPU_HAS_SMARTMIPS
+	REG_OFFSET_NAME(acx, acx),
+#endif
+	REG_OFFSET_NAME(c0_badvaddr, cp0_badvaddr),
+	REG_OFFSET_NAME(c0_cause, cp0_cause),
+	REG_OFFSET_NAME(c0_epc, cp0_epc),
+#ifdef CONFIG_CPU_CAVIUM_OCTEON
+	REG_OFFSET_NAME(mpl0, mpl[0]),
+	REG_OFFSET_NAME(mpl1, mpl[1]),
+	REG_OFFSET_NAME(mpl2, mpl[2]),
+	REG_OFFSET_NAME(mtp0, mtp[0]),
+	REG_OFFSET_NAME(mtp1, mtp[1]),
+	REG_OFFSET_NAME(mtp2, mtp[2]),
+#endif
+	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;
+}
+
+#if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
+
+static const struct user_regset mips_regsets[] = {
+	[REGSET_GPR] = {
+		.core_note_type	= NT_PRSTATUS,
+		.n		= ELF_NGREG,
+		.size		= sizeof(unsigned int),
+		.align		= sizeof(unsigned int),
+		.regset_get		= gpr32_get,
+		.set		= gpr32_set,
+	},
+	[REGSET_DSP] = {
+		.core_note_type	= NT_MIPS_DSP,
+		.n		= NUM_DSP_REGS + 1,
+		.size		= sizeof(u32),
+		.align		= sizeof(u32),
+		.regset_get		= dsp32_get,
+		.set		= dsp32_set,
+		.active		= dsp_active,
+	},
+#ifdef CONFIG_MIPS_FP_SUPPORT
+	[REGSET_FPR] = {
+		.core_note_type	= NT_PRFPREG,
+		.n		= ELF_NFPREG,
+		.size		= sizeof(elf_fpreg_t),
+		.align		= sizeof(elf_fpreg_t),
+		.regset_get		= fpr_get,
+		.set		= fpr_set,
+	},
+	[REGSET_FP_MODE] = {
+		.core_note_type	= NT_MIPS_FP_MODE,
+		.n		= 1,
+		.size		= sizeof(int),
+		.align		= sizeof(int),
+		.regset_get		= fp_mode_get,
+		.set		= fp_mode_set,
+	},
+#endif
+#ifdef CONFIG_CPU_HAS_MSA
+	[REGSET_MSA] = {
+		.core_note_type	= NT_MIPS_MSA,
+		.n		= NUM_FPU_REGS + 1,
+		.size		= 16,
+		.align		= 16,
+		.regset_get		= msa_get,
+		.set		= msa_set,
+	},
+#endif
+};
+
+static const struct user_regset_view user_mips_view = {
+	.name		= "mips",
+	.e_machine	= ELF_ARCH,
+	.ei_osabi	= ELF_OSABI,
+	.regsets	= mips_regsets,
+	.n		= ARRAY_SIZE(mips_regsets),
+};
+
+#endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
+
+#ifdef CONFIG_64BIT
+
+static const struct user_regset mips64_regsets[] = {
+	[REGSET_GPR] = {
+		.core_note_type	= NT_PRSTATUS,
+		.n		= ELF_NGREG,
+		.size		= sizeof(unsigned long),
+		.align		= sizeof(unsigned long),
+		.regset_get		= gpr64_get,
+		.set		= gpr64_set,
+	},
+	[REGSET_DSP] = {
+		.core_note_type	= NT_MIPS_DSP,
+		.n		= NUM_DSP_REGS + 1,
+		.size		= sizeof(u64),
+		.align		= sizeof(u64),
+		.regset_get		= dsp64_get,
+		.set		= dsp64_set,
+		.active		= dsp_active,
+	},
+#ifdef CONFIG_MIPS_FP_SUPPORT
+	[REGSET_FP_MODE] = {
+		.core_note_type	= NT_MIPS_FP_MODE,
+		.n		= 1,
+		.size		= sizeof(int),
+		.align		= sizeof(int),
+		.regset_get		= fp_mode_get,
+		.set		= fp_mode_set,
+	},
+	[REGSET_FPR] = {
+		.core_note_type	= NT_PRFPREG,
+		.n		= ELF_NFPREG,
+		.size		= sizeof(elf_fpreg_t),
+		.align		= sizeof(elf_fpreg_t),
+		.regset_get		= fpr_get,
+		.set		= fpr_set,
+	},
+#endif
+#ifdef CONFIG_CPU_HAS_MSA
+	[REGSET_MSA] = {
+		.core_note_type	= NT_MIPS_MSA,
+		.n		= NUM_FPU_REGS + 1,
+		.size		= 16,
+		.align		= 16,
+		.regset_get		= msa_get,
+		.set		= msa_set,
+	},
+#endif
+};
+
+static const struct user_regset_view user_mips64_view = {
+	.name		= "mips64",
+	.e_machine	= ELF_ARCH,
+	.ei_osabi	= ELF_OSABI,
+	.regsets	= mips64_regsets,
+	.n		= ARRAY_SIZE(mips64_regsets),
+};
+
+#ifdef CONFIG_MIPS32_N32
+
+static const struct user_regset_view user_mipsn32_view = {
+	.name		= "mipsn32",
+	.e_flags	= EF_MIPS_ABI2,
+	.e_machine	= ELF_ARCH,
+	.ei_osabi	= ELF_OSABI,
+	.regsets	= mips64_regsets,
+	.n		= ARRAY_SIZE(mips64_regsets),
+};
+
+#endif /* CONFIG_MIPS32_N32 */
+
+#endif /* CONFIG_64BIT */
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+#ifdef CONFIG_32BIT
+	return &user_mips_view;
+#else
+#ifdef CONFIG_MIPS32_O32
+	if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
+		return &user_mips_view;
+#endif
+#ifdef CONFIG_MIPS32_N32
+	if (test_tsk_thread_flag(task, TIF_32BIT_ADDR))
+		return &user_mipsn32_view;
+#endif
+	return &user_mips64_view;
+#endif
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+		 unsigned long addr, unsigned long data)
+{
+	int ret;
+	void __user *addrp = (void __user *) addr;
+	void __user *datavp = (void __user *) data;
+	unsigned long __user *datalp = (void __user *) data;
+
+	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:
+		ret = generic_ptrace_peekdata(child, addr, data);
+		break;
+
+	/* Read the word at location addr in the USER area. */
+	case PTRACE_PEEKUSR: {
+		struct pt_regs *regs;
+		unsigned long tmp = 0;
+
+		regs = task_pt_regs(child);
+		ret = 0;  /* Default return value. */
+
+		switch (addr) {
+		case 0 ... 31:
+			tmp = regs->regs[addr];
+			break;
+#ifdef CONFIG_MIPS_FP_SUPPORT
+		case FPR_BASE ... FPR_BASE + 31: {
+			union fpureg *fregs;
+
+			if (!tsk_used_math(child)) {
+				/* FP not yet used */
+				tmp = -1;
+				break;
+			}
+			fregs = get_fpu_regs(child);
+
+#ifdef CONFIG_32BIT
+			if (test_tsk_thread_flag(child, TIF_32BIT_FPREGS)) {
+				/*
+				 * The odd registers are actually the high
+				 * order bits of the values stored in the even
+				 * registers.
+				 */
+				tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
+						addr & 1);
+				break;
+			}
+#endif
+			tmp = get_fpr64(&fregs[addr - FPR_BASE], 0);
+			break;
+		}
+		case FPC_CSR:
+			tmp = child->thread.fpu.fcr31;
+			break;
+		case FPC_EIR:
+			/* implementation / version register */
+			tmp = boot_cpu_data.fpu_id;
+			break;
+#endif
+		case PC:
+			tmp = regs->cp0_epc;
+			break;
+		case CAUSE:
+			tmp = regs->cp0_cause;
+			break;
+		case BADVADDR:
+			tmp = regs->cp0_badvaddr;
+			break;
+		case MMHI:
+			tmp = regs->hi;
+			break;
+		case MMLO:
+			tmp = regs->lo;
+			break;
+#ifdef CONFIG_CPU_HAS_SMARTMIPS
+		case ACX:
+			tmp = regs->acx;
+			break;
+#endif
+		case DSP_BASE ... DSP_BASE + 5: {
+			dspreg_t *dregs;
+
+			if (!cpu_has_dsp) {
+				tmp = 0;
+				ret = -EIO;
+				goto out;
+			}
+			dregs = __get_dsp_regs(child);
+			tmp = dregs[addr - DSP_BASE];
+			break;
+		}
+		case DSP_CONTROL:
+			if (!cpu_has_dsp) {
+				tmp = 0;
+				ret = -EIO;
+				goto out;
+			}
+			tmp = child->thread.dsp.dspcontrol;
+			break;
+		default:
+			tmp = 0;
+			ret = -EIO;
+			goto out;
+		}
+		ret = put_user(tmp, datalp);
+		break;
+	}
+
+	/* when I and D space are separate, this will have to be fixed. */
+	case PTRACE_POKETEXT: /* write the word at location addr. */
+	case PTRACE_POKEDATA:
+		ret = generic_ptrace_pokedata(child, addr, data);
+		break;
+
+	case PTRACE_POKEUSR: {
+		struct pt_regs *regs;
+		ret = 0;
+		regs = task_pt_regs(child);
+
+		switch (addr) {
+		case 0 ... 31:
+			regs->regs[addr] = data;
+			/* System call number may have been changed */
+			if (addr == 2)
+				mips_syscall_update_nr(child, regs);
+			else if (addr == 4 &&
+				 mips_syscall_is_indirect(child, regs))
+				mips_syscall_update_nr(child, regs);
+			break;
+#ifdef CONFIG_MIPS_FP_SUPPORT
+		case FPR_BASE ... FPR_BASE + 31: {
+			union fpureg *fregs = get_fpu_regs(child);
+
+			init_fp_ctx(child);
+#ifdef CONFIG_32BIT
+			if (test_tsk_thread_flag(child, TIF_32BIT_FPREGS)) {
+				/*
+				 * The odd registers are actually the high
+				 * order bits of the values stored in the even
+				 * registers.
+				 */
+				set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
+					  addr & 1, data);
+				break;
+			}
+#endif
+			set_fpr64(&fregs[addr - FPR_BASE], 0, data);
+			break;
+		}
+		case FPC_CSR:
+			init_fp_ctx(child);
+			ptrace_setfcr31(child, data);
+			break;
+#endif
+		case PC:
+			regs->cp0_epc = data;
+			break;
+		case MMHI:
+			regs->hi = data;
+			break;
+		case MMLO:
+			regs->lo = data;
+			break;
+#ifdef CONFIG_CPU_HAS_SMARTMIPS
+		case ACX:
+			regs->acx = data;
+			break;
+#endif
+		case DSP_BASE ... DSP_BASE + 5: {
+			dspreg_t *dregs;
+
+			if (!cpu_has_dsp) {
+				ret = -EIO;
+				break;
+			}
+
+			dregs = __get_dsp_regs(child);
+			dregs[addr - DSP_BASE] = data;
+			break;
+		}
+		case DSP_CONTROL:
+			if (!cpu_has_dsp) {
+				ret = -EIO;
+				break;
+			}
+			child->thread.dsp.dspcontrol = data;
+			break;
+		default:
+			/* The rest are not allowed. */
+			ret = -EIO;
+			break;
+		}
+		break;
+		}
+
+	case PTRACE_GETREGS:
+		ret = ptrace_getregs(child, datavp);
+		break;
+
+	case PTRACE_SETREGS:
+		ret = ptrace_setregs(child, datavp);
+		break;
+
+#ifdef CONFIG_MIPS_FP_SUPPORT
+	case PTRACE_GETFPREGS:
+		ret = ptrace_getfpregs(child, datavp);
+		break;
+
+	case PTRACE_SETFPREGS:
+		ret = ptrace_setfpregs(child, datavp);
+		break;
+#endif
+	case PTRACE_GET_THREAD_AREA:
+		ret = put_user(task_thread_info(child)->tp_value, datalp);
+		break;
+
+	case PTRACE_GET_WATCH_REGS:
+		ret = ptrace_get_watch_regs(child, addrp);
+		break;
+
+	case PTRACE_SET_WATCH_REGS:
+		ret = ptrace_set_watch_regs(child, addrp);
+		break;
+
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+ out:
+	return ret;
+}
+
+/*
+ * Notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+asmlinkage long syscall_trace_enter(struct pt_regs *regs, long syscall)
+{
+	user_exit();
+
+	current_thread_info()->syscall = syscall;
+
+	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
+		if (tracehook_report_syscall_entry(regs))
+			return -1;
+		syscall = current_thread_info()->syscall;
+	}
+
+#ifdef CONFIG_SECCOMP
+	if (unlikely(test_thread_flag(TIF_SECCOMP))) {
+		int ret, i;
+		struct seccomp_data sd;
+		unsigned long args[6];
+
+		sd.nr = syscall;
+		sd.arch = syscall_get_arch(current);
+		syscall_get_arguments(current, regs, args);
+		for (i = 0; i < 6; i++)
+			sd.args[i] = args[i];
+		sd.instruction_pointer = KSTK_EIP(current);
+
+		ret = __secure_computing(&sd);
+		if (ret == -1)
+			return ret;
+		syscall = current_thread_info()->syscall;
+	}
+#endif
+
+	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
+		trace_sys_enter(regs, regs->regs[2]);
+
+	audit_syscall_entry(syscall, regs->regs[4], regs->regs[5],
+			    regs->regs[6], regs->regs[7]);
+
+	/*
+	 * Negative syscall numbers are mistaken for rejected syscalls, but
+	 * won't have had the return value set appropriately, so we do so now.
+	 */
+	if (syscall < 0)
+		syscall_set_return_value(current, regs, -ENOSYS, 0);
+	return syscall;
+}
+
+/*
+ * Notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+asmlinkage void syscall_trace_leave(struct pt_regs *regs)
+{
+        /*
+	 * We may come here right after calling schedule_user()
+	 * or do_notify_resume(), in which case we can be in RCU
+	 * user mode.
+	 */
+	user_exit();
+
+	audit_syscall_exit(regs);
+
+	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
+		trace_sys_exit(regs, regs_return_value(regs));
+
+	if (test_thread_flag(TIF_SYSCALL_TRACE))
+		tracehook_report_syscall_exit(regs, 0);
+
+	user_enter();
+}