/*
* do a signal return; undo the signal stack.
*/
static int restore_sigcontext(struct pt_regs *regs,
struct sigcontext __user *sc, long *_d0)
{
unsigned int err = 0;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
if (is_using_fpu(current))
fpu_kill_state(current);
#define COPY(x) err |= __get_user(regs->x, &sc->x)
COPY(d1); COPY(d2); COPY(d3);
COPY(a0); COPY(a1); COPY(a2); COPY(a3);
COPY(e0); COPY(e1); COPY(e2); COPY(e3);
COPY(e4); COPY(e5); COPY(e6); COPY(e7);
COPY(lar); COPY(lir);
COPY(mdr); COPY(mdrq);
COPY(mcvf); COPY(mcrl); COPY(mcrh);
COPY(sp); COPY(pc);
#undef COPY
{
unsigned int tmpflags;
#ifndef CONFIG_MN10300_USING_JTAG
#define USER_EPSW (EPSW_FLAG_Z | EPSW_FLAG_N | EPSW_FLAG_C | EPSW_FLAG_V | \
EPSW_T | EPSW_nAR)
#else
#define USER_EPSW (EPSW_FLAG_Z | EPSW_FLAG_N | EPSW_FLAG_C | EPSW_FLAG_V | \
EPSW_nAR)
#endif
err |= __get_user(tmpflags, &sc->epsw);
regs->epsw = (regs->epsw & ~USER_EPSW) |
(tmpflags & USER_EPSW);
regs->orig_d0 = -1; /* disable syscall checks */
}
{
struct fpucontext *buf;
err |= __get_user(buf, &sc->fpucontext);
if (buf) {
if (verify_area(VERIFY_READ, buf, sizeof(*buf)))
goto badframe;
err |= fpu_restore_sigcontext(buf);
}
}
err |= __get_user(*_d0, &sc->d0);
return err;
badframe:
return 1;
}
/*
* fill in the FPU structure for a core dump
*/
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpreg)
{
struct task_struct *tsk = current;
int fpvalid;
fpvalid = is_using_fpu(tsk);
if (fpvalid) {
unlazy_fpu(tsk);
memcpy(fpreg, &tsk->thread.fpu_state, sizeof(*fpreg));
}
return fpvalid;
}
/*
* save the FPU state to a signal context
*/
int fpu_setup_sigcontext(struct fpucontext *fpucontext)
{
struct task_struct *tsk = current;
if (!is_using_fpu(tsk))
return 0;
/* transfer the current FPU state to memory and cause fpu_init() to be
* triggered by the next attempted FPU operation by the current
* process.
*/
preempt_disable();
#ifndef CONFIG_LAZY_SAVE_FPU
if (tsk->thread.fpu_flags & THREAD_HAS_FPU) {
fpu_save(&tsk->thread.fpu_state);
tsk->thread.uregs->epsw &= ~EPSW_FE;
tsk->thread.fpu_flags &= ~THREAD_HAS_FPU;
}
#else /* !CONFIG_LAZY_SAVE_FPU */
if (fpu_state_owner == tsk) {
fpu_save(&tsk->thread.fpu_state);
fpu_state_owner->thread.uregs->epsw &= ~EPSW_FE;
fpu_state_owner = NULL;
}
#endif /* !CONFIG_LAZY_SAVE_FPU */
preempt_enable();
/* we no longer have a valid current FPU state */
clear_using_fpu(tsk);
/* transfer the saved FPU state onto the userspace stack */
if (copy_to_user(fpucontext,
&tsk->thread.fpu_state,
min(sizeof(struct fpu_state_struct),
sizeof(struct fpucontext))))
return -1;
return 1;
}
/*
* handle an FPU operational exception
* - there's a possibility that if the FPU is asynchronous, the signal might
* be meant for a process other than the current one
*/
asmlinkage void fpu_exception(struct pt_regs *regs, enum exception_code code)
{
struct task_struct *tsk = current;
siginfo_t info;
u32 fpcr;
if (!user_mode(regs))
die_if_no_fixup("An FPU Operation exception happened in"
" kernel space\n",
regs, code);
if (!is_using_fpu(tsk))
die_if_no_fixup("An FPU Operation exception happened,"
" but the FPU is not in use",
regs, code);
info.si_signo = SIGFPE;
info.si_errno = 0;
info.si_addr = (void *) tsk->thread.uregs->pc;
info.si_code = FPE_FLTINV;
unlazy_fpu(tsk);
fpcr = tsk->thread.fpu_state.fpcr;
if (fpcr & FPCR_EC_Z)
info.si_code = FPE_FLTDIV;
else if (fpcr & FPCR_EC_O)
info.si_code = FPE_FLTOVF;
else if (fpcr & FPCR_EC_U)
info.si_code = FPE_FLTUND;
else if (fpcr & FPCR_EC_I)
info.si_code = FPE_FLTRES;
force_sig_info(SIGFPE, &info, tsk);
}
/*
* determine if the FPU registers have actually been used
*/
static int fpuregs_active(struct task_struct *target,
const struct user_regset *regset)
{
return is_using_fpu(target) ? regset->n : 0;
}
