sigutil_32.c

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#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/thread_info.h>
#include <linux/uaccess.h>
#include <linux/sched.h>

#include <asm/sigcontext.h>
#include <asm/fpumacro.h>
#include <asm/ptrace.h>
#include <asm/switch_to.h>

#include "sigutil.h"

int save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
    int err = 0;
#ifdef CONFIG_SMP
    if (test_tsk_thread_flag(current, TIF_USEDFPU)) {
        put_psr(get_psr() | PSR_EF);
        fpsave(&current->thread.float_regs[0], &current->thread.fsr,
               &current->thread.fpqueue[0], &current->thread.fpqdepth);
        regs->psr &= ~(PSR_EF);
        clear_tsk_thread_flag(current, TIF_USEDFPU);
    }
#else
    if (current == last_task_used_math) {
        put_psr(get_psr() | PSR_EF);
        fpsave(&current->thread.float_regs[0], &current->thread.fsr,
               &current->thread.fpqueue[0], &current->thread.fpqdepth);
        last_task_used_math = NULL;
        regs->psr &= ~(PSR_EF);
    }
#endif
    err |= __copy_to_user(&fpu->si_float_regs[0],
                  &current->thread.float_regs[0],
                  (sizeof(unsigned long) * 32));
    err |= __put_user(current->thread.fsr, &fpu->si_fsr);
    err |= __put_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
    if (current->thread.fpqdepth != 0)
        err |= __copy_to_user(&fpu->si_fpqueue[0],
                      &current->thread.fpqueue[0],
                      ((sizeof(unsigned long) +
                      (sizeof(unsigned long *)))*16));
    clear_used_math();
    return err;
}

int restore_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
    int err;
#ifdef CONFIG_SMP
    if (test_tsk_thread_flag(current, TIF_USEDFPU))
        regs->psr &= ~PSR_EF;
#else
    if (current == last_task_used_math) {
        last_task_used_math = NULL;
        regs->psr &= ~PSR_EF;
    }
#endif
    set_used_math();
    clear_tsk_thread_flag(current, TIF_USEDFPU);

    if (!access_ok(VERIFY_READ, fpu, sizeof(*fpu)))
        return -EFAULT;

    err = __copy_from_user(&current->thread.float_regs[0], &fpu->si_float_regs[0],
                   (sizeof(unsigned long) * 32));
    err |= __get_user(current->thread.fsr, &fpu->si_fsr);
    err |= __get_user(current->thread.fpqdepth, &fpu->si_fpqdepth);
    if (current->thread.fpqdepth != 0)
        err |= __copy_from_user(&current->thread.fpqueue[0],
                    &fpu->si_fpqueue[0],
                    ((sizeof(unsigned long) +
                    (sizeof(unsigned long *)))*16));
    return err;
}

int save_rwin_state(int wsaved, __siginfo_rwin_t __user *rwin)
{
    int i, err = __put_user(wsaved, &rwin->wsaved);

    for (i = 0; i < wsaved; i++) {
        struct reg_window32 *rp;
        unsigned long fp;

        rp = &current_thread_info()->reg_window[i];
        fp = current_thread_info()->rwbuf_stkptrs[i];
        err |= copy_to_user(&rwin->reg_window[i], rp,
                    sizeof(struct reg_window32));
        err |= __put_user(fp, &rwin->rwbuf_stkptrs[i]);
    }
    return err;
}

int restore_rwin_state(__siginfo_rwin_t __user *rp)
{
    struct thread_info *t = current_thread_info();
    int i, wsaved, err;

    __get_user(wsaved, &rp->wsaved);
    if (wsaved > NSWINS)
        return -EFAULT;

    err = 0;
    for (i = 0; i < wsaved; i++) {
        err |= copy_from_user(&t->reg_window[i],
                      &rp->reg_window[i],
                      sizeof(struct reg_window32));
        err |= __get_user(t->rwbuf_stkptrs[i],
                  &rp->rwbuf_stkptrs[i]);
    }
    if (err)
        return err;

    t->w_saved = wsaved;
    synchronize_user_stack();
    if (t->w_saved)
        return -EFAULT;
    return 0;

}