linux/arch/mips/kernel/ptrace.c
Maciej W. Rozycki 1ae22a0e35
MIPS: Add FP_MODE regset support
Define an NT_MIPS_FP_MODE core file note and implement a corresponding
regset holding the state handled by PR_SET_FP_MODE and PR_GET_FP_MODE
prctl(2) requests.  This lets debug software correctly interpret the
contents of floating-point general registers both in live debugging and
in core files, and also switch floating-point modes of a live process.

[paul.burton@mips.com:
  - Changed NT_MIPS_FP_MODE to 0x801 to match first nibble of
    NT_MIPS_DSP, which was also changed to avoid a conflict.]

Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/19331/
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
2018-07-19 13:58:44 -07:00

1326 lines
32 KiB
C

/*
* 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/pgtable.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>
static void init_fp_ctx(struct task_struct *target)
{
/* If FP has been used then the target already has context */
if (tsk_used_math(target))
return;
/* Begin with data registers set to all 1s... */
memset(&target->thread.fpu.fpr, ~0, sizeof(target->thread.fpu.fpr));
/* FCSR has been preset by `mips_set_personality_nan'. */
/*
* Record that the target has "used" math, such that the context
* just initialised, and any modifications made by the caller,
* aren't discarded.
*/
set_stopped_child_used_math(target);
}
/*
* 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);
}
/*
* 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);
}
/*
* 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(VERIFY_WRITE, 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(VERIFY_READ, 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_getfpregs(struct task_struct *child, __u32 __user *data)
{
int i;
if (!access_ok(VERIFY_WRITE, data, 33 * 8))
return -EIO;
if (tsk_used_math(child)) {
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(VERIFY_READ, 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;
}
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(VERIFY_WRITE, 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(VERIFY_READ, 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,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
struct pt_regs *regs = task_pt_regs(target);
u32 uregs[ELF_NGREG] = {};
mips_dump_regs32(uregs, regs);
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
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,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
struct pt_regs *regs = task_pt_regs(target);
u64 uregs[ELF_NGREG] = {};
mips_dump_regs64(uregs, regs);
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
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 */
/*
* 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 int fpr_get_fpa(struct task_struct *target,
unsigned int *pos, unsigned int *count,
void **kbuf, void __user **ubuf)
{
return user_regset_copyout(pos, count, kbuf, ubuf,
&target->thread.fpu,
0, 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 int fpr_get_msa(struct task_struct *target,
unsigned int *pos, unsigned int *count,
void **kbuf, 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; i++) {
fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
err = user_regset_copyout(pos, count, kbuf, ubuf,
&fpr_val, i * sizeof(elf_fpreg_t),
(i + 1) * sizeof(elf_fpreg_t));
if (err)
return err;
}
return 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,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
const int fcr31_pos = NUM_FPU_REGS * sizeof(elf_fpreg_t);
const int fir_pos = fcr31_pos + sizeof(u32);
int err;
if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
err = fpr_get_fpa(target, &pos, &count, &kbuf, &ubuf);
else
err = fpr_get_msa(target, &pos, &count, &kbuf, &ubuf);
if (err)
return err;
err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.fpu.fcr31,
fcr31_pos, fcr31_pos + sizeof(u32));
if (err)
return err;
err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&boot_cpu_data.fpu_id,
fir_pos, fir_pos + sizeof(u32));
return err;
}
/*
* 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;
}
#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,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
unsigned int start, num_regs, i;
u32 dspregs[NUM_DSP_REGS + 1];
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;
for (i = start; i < num_regs; i++)
switch (i) {
case 0 ... NUM_DSP_REGS - 1:
dspregs[i] = target->thread.dsp.dspr[i];
break;
case NUM_DSP_REGS:
dspregs[i] = target->thread.dsp.dspcontrol;
break;
}
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, dspregs, 0,
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,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
unsigned int start, num_regs, i;
u64 dspregs[NUM_DSP_REGS + 1];
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;
for (i = start; i < num_regs; i++)
switch (i) {
case 0 ... NUM_DSP_REGS - 1:
dspregs[i] = target->thread.dsp.dspr[i];
break;
case NUM_DSP_REGS:
dspregs[i] = target->thread.dsp.dspcontrol;
break;
}
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, dspregs, 0,
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;
}
/* 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,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
int fp_mode;
fp_mode = mips_get_process_fp_mode(target);
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &fp_mode, 0,
sizeof(fp_mode));
}
/*
* 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;
}
enum mips_regset {
REGSET_GPR,
REGSET_FPR,
REGSET_DSP,
REGSET_FP_MODE,
};
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),
.get = gpr32_get,
.set = gpr32_set,
},
[REGSET_FPR] = {
.core_note_type = NT_PRFPREG,
.n = ELF_NFPREG,
.size = sizeof(elf_fpreg_t),
.align = sizeof(elf_fpreg_t),
.get = fpr_get,
.set = fpr_set,
},
[REGSET_DSP] = {
.core_note_type = NT_MIPS_DSP,
.n = NUM_DSP_REGS + 1,
.size = sizeof(u32),
.align = sizeof(u32),
.get = dsp32_get,
.set = dsp32_set,
.active = dsp_active,
},
[REGSET_FP_MODE] = {
.core_note_type = NT_MIPS_FP_MODE,
.n = 1,
.size = sizeof(int),
.align = sizeof(int),
.get = fp_mode_get,
.set = fp_mode_set,
},
};
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),
.get = gpr64_get,
.set = gpr64_set,
},
[REGSET_FPR] = {
.core_note_type = NT_PRFPREG,
.n = ELF_NFPREG,
.size = sizeof(elf_fpreg_t),
.align = sizeof(elf_fpreg_t),
.get = fpr_get,
.set = fpr_set,
},
[REGSET_DSP] = {
.core_note_type = NT_MIPS_DSP,
.n = NUM_DSP_REGS + 1,
.size = sizeof(u64),
.align = sizeof(u64),
.get = dsp64_get,
.set = dsp64_set,
.active = dsp_active,
},
[REGSET_FP_MODE] = {
.core_note_type = NT_MIPS_FP_MODE,
.n = 1,
.size = sizeof(int),
.align = sizeof(int),
.get = fp_mode_get,
.set = fp_mode_set,
},
};
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;
union fpureg *fregs;
unsigned long tmp = 0;
regs = task_pt_regs(child);
ret = 0; /* Default return value. */
switch (addr) {
case 0 ... 31:
tmp = regs->regs[addr];
break;
case FPR_BASE ... FPR_BASE + 31:
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 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 FPC_CSR:
tmp = child->thread.fpu.fcr31;
break;
case FPC_EIR:
/* implementation / version register */
tmp = boot_cpu_data.fpu_id;
break;
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;
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 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 FPC_CSR:
init_fp_ctx(child);
ptrace_setfcr31(child, data);
break;
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;
case PTRACE_GETFPREGS:
ret = ptrace_getfpregs(child, datavp);
break;
case PTRACE_SETFPREGS:
ret = ptrace_setfpregs(child, datavp);
break;
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();
syscall_get_arguments(current, regs, 0, 6, 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();
}