static int protected_restore_fp_context32(struct sigcontext32 __user *sc,
unsigned used_math)
{
int err, tmp __maybe_unused;
bool restore_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
while (1) {
lock_fpu_owner();
if (is_fpu_owner()) {
err = restore_fp_context32(sc);
if (restore_msa && !err) {
enable_msa();
err = _restore_msa_context32(sc);
} else {
/* signal handler may have used MSA */
disable_msa();
}
unlock_fpu_owner();
} else {
unlock_fpu_owner();
err = copy_fp_from_sigcontext32(sc);
if (restore_msa && !err)
err = copy_msa_from_sigcontext32(sc);
}
if (likely(!err))
break;
/* touch the sigcontext and try again */
err = __get_user(tmp, &sc->sc_fpregs[0]) |
__get_user(tmp, &sc->sc_fpregs[31]) |
__get_user(tmp, &sc->sc_fpc_csr);
if (err)
break; /* really bad sigcontext */
}
return err;
}
void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp)
{
unsigned long status;
/* New thread loses kernel privileges. */
status = regs->cp0_status & ~(ST0_CU0|ST0_CU1|ST0_FR|KU_MASK);
status |= KU_USER;
regs->cp0_status = status;
clear_used_math();
clear_fpu_owner();
init_dsp();
clear_thread_flag(TIF_USEDMSA);
clear_thread_flag(TIF_MSA_CTX_LIVE);
disable_msa();
regs->cp0_epc = pc;
regs->regs[29] = sp;
}
static int protected_restore_fp_context(struct sigcontext __user *sc,
unsigned used_math)
{
int err, tmp __maybe_unused;
bool restore_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
#ifndef CONFIG_EVA
while (1) {
lock_fpu_owner();
if (is_fpu_owner()) {
err = restore_fp_context(sc);
if (restore_msa && !err) {
enable_msa();
err = _restore_msa_context(sc);
} else {
/* signal handler may have used MSA */
disable_msa();
}
unlock_fpu_owner();
} else {
unlock_fpu_owner();
err = copy_fp_from_sigcontext(sc);
if (!err && (used_math & USEDMATH_MSA))
err = copy_msa_from_sigcontext(sc);
}
if (likely(!err))
break;
/* touch the sigcontext and try again */
err = __get_user(tmp, &sc->sc_fpregs[0]) |
__get_user(tmp, &sc->sc_fpregs[31]) |
__get_user(tmp, &sc->sc_fpc_csr);
if (err)
break; /* really bad sigcontext */
}
#else
/*
* EVA does not have FPU EVA instructions so restoring fpu context
* directly does not work.
*/
enable_msa();
lose_fpu(0);
err = restore_fp_context(sc); /* this might fail */
if (restore_msa && !err)
err = copy_msa_from_sigcontext(sc);
#endif
return err;
}
int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
unsigned int used_math;
unsigned long treg;
int err = 0;
int i;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
err |= __get_user(regs->cp0_epc, &sc->sc_pc);
#ifdef CONFIG_CPU_HAS_SMARTMIPS
err |= __get_user(regs->acx, &sc->sc_acx);
#endif
err |= __get_user(regs->hi, &sc->sc_mdhi);
err |= __get_user(regs->lo, &sc->sc_mdlo);
if (cpu_has_dsp) {
err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
}
for (i = 1; i < 32; i++)
err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
err |= __get_user(used_math, &sc->sc_used_math);
conditional_used_math(used_math);
if (used_math) {
/* restore fpu context if we have used it before */
if (!err)
err = check_and_restore_fp_context(sc, used_math);
} else {
/* signal handler may have used FPU or MSA. Disable them. */
disable_msa();
lose_fpu(0);
}
return err;
}
/*
* Helper routines
*/
static int protected_save_fp_context(struct sigcontext __user *sc,
unsigned used_math)
{
int err;
bool save_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
#ifndef CONFIG_EVA
while (1) {
lock_fpu_owner();
if (is_fpu_owner()) {
err = save_fp_context(sc);
if (save_msa && !err)
err = _save_msa_context(sc);
unlock_fpu_owner();
} else {
unlock_fpu_owner();
err = copy_fp_to_sigcontext(sc);
if (save_msa && !err)
err = copy_msa_to_sigcontext(sc);
}
if (likely(!err))
break;
/* touch the sigcontext and try again */
err = __put_user(0, &sc->sc_fpregs[0]) |
__put_user(0, &sc->sc_fpregs[31]) |
__put_user(0, &sc->sc_fpc_csr);
if (err)
break; /* really bad sigcontext */
}
#else
/*
* EVA does not have FPU EVA instructions so saving fpu context directly
* does not work.
*/
disable_msa();
lose_fpu(1);
err = save_fp_context(sc); /* this might fail */
if (save_msa && !err)
err = copy_msa_to_sigcontext(sc);
#endif
return err;
}
