x86: x86 user_regset math_emu

This converts the ptrace/signal accessors for i387 math_emu
state to the user_regset interface style, and calls these
from the old interfaces.

It also cleans up math_emulate's ptrace check to be a
single-step check, which is what it really wants.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Roland McGrath 2008-01-30 13:31:49 +01:00 committed by Ingo Molnar
parent cc927a25bd
commit ff0ebb23c6
1 changed files with 54 additions and 32 deletions

View File

@ -25,10 +25,11 @@
+---------------------------------------------------------------------------*/
#include <linux/signal.h>
#include <linux/ptrace.h>
#include <linux/regset.h>
#include <asm/uaccess.h>
#include <asm/desc.h>
#include <asm/user.h>
#include "fpu_system.h"
#include "fpu_emu.h"
@ -198,9 +199,7 @@ asmlinkage void math_emulate(long arg)
code_limit = 0xffffffff;
}
FPU_lookahead = 1;
if (current->ptrace & PT_PTRACED)
FPU_lookahead = 0;
FPU_lookahead = !(FPU_EFLAGS & X86_EFLAGS_TF);
if (!valid_prefix(&byte1, (u_char __user **) & FPU_EIP,
&addr_modes.override)) {
@ -673,31 +672,37 @@ void math_abort(struct info *info, unsigned int signal)
#define sstatus_word() \
((S387->swd & ~SW_Top & 0xffff) | ((S387->ftop << SW_Top_Shift) & SW_Top))
int restore_i387_soft(void *s387, struct _fpstate __user *buf)
int fpregs_soft_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
u_char __user *d = (u_char __user *) buf;
struct i387_soft_struct *s387 = &target->thread.i387.soft;
void *space = s387->st_space;
int ret;
int offset, other, i, tags, regnr, tag, newtop;
RE_ENTRANT_CHECK_OFF;
FPU_access_ok(VERIFY_READ, d, 7 * 4 + 8 * 10);
if (__copy_from_user(&S387->cwd, d, 7 * 4))
return -1;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, s387, 0,
offsetof(struct i387_soft_struct, st_space));
RE_ENTRANT_CHECK_ON;
d += 7 * 4;
if (ret)
return ret;
S387->ftop = (S387->swd >> SW_Top_Shift) & 7;
offset = (S387->ftop & 7) * 10;
other = 80 - offset;
RE_ENTRANT_CHECK_OFF;
/* Copy all registers in stack order. */
if (__copy_from_user(((u_char *) & S387->st_space) + offset, d, other))
return -1;
if (offset)
if (__copy_from_user
((u_char *) & S387->st_space, d + other, offset))
return -1;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
space + offset, 0, other);
if (!ret && offset)
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
space, 0, offset);
RE_ENTRANT_CHECK_ON;
/* The tags may need to be corrected now. */
@ -716,16 +721,21 @@ int restore_i387_soft(void *s387, struct _fpstate __user *buf)
}
S387->twd = tags;
return 0;
return ret;
}
int save_i387_soft(void *s387, struct _fpstate __user * buf)
int fpregs_soft_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
u_char __user *d = (u_char __user *) buf;
struct i387_soft_struct *s387 = &target->thread.i387.soft;
const void *space = s387->st_space;
int ret;
int offset = (S387->ftop & 7) * 10, other = 80 - offset;
RE_ENTRANT_CHECK_OFF;
FPU_access_ok(VERIFY_WRITE, d, 7 * 4 + 8 * 10);
#ifdef PECULIAR_486
S387->cwd &= ~0xe080;
/* An 80486 sets nearly all of the reserved bits to 1. */
@ -735,21 +745,33 @@ int save_i387_soft(void *s387, struct _fpstate __user * buf)
S387->fcs &= ~0xf8000000;
S387->fos |= 0xffff0000;
#endif /* PECULIAR_486 */
if (__copy_to_user(d, &S387->cwd, 7 * 4))
return -1;
RE_ENTRANT_CHECK_ON;
d += 7 * 4;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, s387, 0,
offsetof(struct i387_soft_struct, st_space));
RE_ENTRANT_CHECK_OFF;
/* Copy all registers in stack order. */
if (__copy_to_user(d, ((u_char *) & S387->st_space) + offset, other))
return -1;
if (offset)
if (__copy_to_user
(d + other, (u_char *) & S387->st_space, offset))
return -1;
if (!ret)
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
space + offset, 0, other);
if (!ret)
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
space, 0, offset);
RE_ENTRANT_CHECK_ON;
return 1;
return ret;
}
int save_i387_soft(void *s387, struct _fpstate __user *buf)
{
return fpregs_soft_get(current, NULL,
0, sizeof(struct user_i387_struct),
NULL, buf) ? -1 : 1;
}
int restore_i387_soft(void *s387, struct _fpstate __user *buf)
{
return fpregs_soft_set(current, NULL,
0, sizeof(struct user_i387_struct),
NULL, buf) ? -1 : 1;
}