// SPDX-License-Identifier: GPL-2.0
#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;

        if (((unsigned long) fpu) & 3)
                return -EFAULT;

#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(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;

        if (((unsigned long) rp) & 3)
                return -EFAULT;

        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;

}