linux/arch/mips/kernel/ptrace32.c
Paul Burton 6c79759eca
MIPS: ptrace: Remove FP support when CONFIG_MIPS_FP_SUPPORT=n
When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so remove
the related ptrace support. Besides removing code which should not be
needed, this prepares us for the removal of FPU state in struct
task_struct which this code requires.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21008/
Cc: linux-mips@linux-mips.org
2018-11-09 10:23:17 -08:00

319 lines
7.4 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/compat.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/smp.h>
#include <linux/security.h>
#include <asm/cpu.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/reg.h>
#include <asm/syscall.h>
#include <linux/uaccess.h>
#include <asm/bootinfo.h>
/*
* Tracing a 32-bit process with a 64-bit strace and vice versa will not
* work. I don't know how to fix this.
*/
long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
compat_ulong_t caddr, compat_ulong_t cdata)
{
int addr = caddr;
int data = cdata;
int ret;
switch (request) {
/*
* Read 4 bytes of the other process' storage
* data is a pointer specifying where the user wants the
* 4 bytes copied into
* addr is a pointer in the user's storage that contains an 8 byte
* address in the other process of the 4 bytes that is to be read
* (this is run in a 32-bit process looking at a 64-bit process)
* when I and D space are separate, these will need to be fixed.
*/
case PTRACE_PEEKTEXT_3264:
case PTRACE_PEEKDATA_3264: {
u32 tmp;
int copied;
u32 __user * addrOthers;
ret = -EIO;
/* Get the addr in the other process that we want to read */
if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)
break;
copied = ptrace_access_vm(child, (u64)addrOthers, &tmp,
sizeof(tmp), FOLL_FORCE);
if (copied != sizeof(tmp))
break;
ret = put_user(tmp, (u32 __user *) (unsigned long) data);
break;
}
/* Read the word at location addr in the USER area. */
case PTRACE_PEEKUSR: {
struct pt_regs *regs;
unsigned int tmp;
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);
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;
}
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 /* CONFIG_MIPS_FP_SUPPORT */
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;
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, (unsigned __user *) (unsigned long) data);
break;
}
/*
* Write 4 bytes into the other process' storage
* data is the 4 bytes that the user wants written
* addr is a pointer in the user's storage that contains an
* 8 byte address in the other process where the 4 bytes
* that is to be written
* (this is run in a 32-bit process looking at a 64-bit process)
* when I and D space are separate, these will need to be fixed.
*/
case PTRACE_POKETEXT_3264:
case PTRACE_POKEDATA_3264: {
u32 __user * addrOthers;
/* Get the addr in the other process that we want to write into */
ret = -EIO;
if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)
break;
ret = 0;
if (ptrace_access_vm(child, (u64)addrOthers, &data,
sizeof(data),
FOLL_FORCE | FOLL_WRITE) == sizeof(data))
break;
ret = -EIO;
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);
if (!tsk_used_math(child)) {
/* FP not yet used */
memset(&child->thread.fpu, ~0,
sizeof(child->thread.fpu));
child->thread.fpu.fcr31 = 0;
}
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;
}
set_fpr64(&fregs[addr - FPR_BASE], 0, data);
break;
}
case FPC_CSR:
child->thread.fpu.fcr31 = data;
break;
#endif /* CONFIG_MIPS_FP_SUPPORT */
case PC:
regs->cp0_epc = data;
break;
case MMHI:
regs->hi = data;
break;
case MMLO:
regs->lo = 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,
(struct user_pt_regs __user *) (__u64) data);
break;
case PTRACE_SETREGS:
ret = ptrace_setregs(child,
(struct user_pt_regs __user *) (__u64) data);
break;
#ifdef CONFIG_MIPS_FP_SUPPORT
case PTRACE_GETFPREGS:
ret = ptrace_getfpregs(child, (__u32 __user *) (__u64) data);
break;
case PTRACE_SETFPREGS:
ret = ptrace_setfpregs(child, (__u32 __user *) (__u64) data);
break;
#endif
case PTRACE_GET_THREAD_AREA:
ret = put_user(task_thread_info(child)->tp_value,
(unsigned int __user *) (unsigned long) data);
break;
case PTRACE_GET_THREAD_AREA_3264:
ret = put_user(task_thread_info(child)->tp_value,
(unsigned long __user *) (unsigned long) data);
break;
case PTRACE_GET_WATCH_REGS:
ret = ptrace_get_watch_regs(child,
(struct pt_watch_regs __user *) (unsigned long) addr);
break;
case PTRACE_SET_WATCH_REGS:
ret = ptrace_set_watch_regs(child,
(struct pt_watch_regs __user *) (unsigned long) addr);
break;
default:
ret = compat_ptrace_request(child, request, addr, data);
break;
}
out:
return ret;
}