/* $NetBSD: copyinstr.c,v 1.24 2022/10/05 08:18:00 rin Exp $ */
/*
* Copyright 2001 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: copyinstr.c,v 1.24 2022/10/05 08:18:00 rin Exp $");
#include <sys/param.h>
#include <uvm/uvm_extern.h>
#include <powerpc/ibm4xx/spr.h>
#include <machine/pcb.h>
int
copyinstr(const void *uaddr, void *kaddr, size_t len, size_t *done)
{
struct pmap *pm = curproc->p_vmspace->vm_map.pmap;
size_t resid;
int rv, msr, pid, tmp, ctx;
struct faultbuf env;
if (__predict_false(len == 0)) {
if (done)
*done = 0;
return 0;
}
if ((rv = setfault(&env))) {
curpcb->pcb_onfault = NULL;
if (done)
*done = 0;
return rv;
}
if (!(ctx = pm->pm_ctx)) {
/* No context -- assign it one */
ctx_alloc(pm);
ctx = pm->pm_ctx;
}
resid = len;
__asm volatile (
"mtctr %[resid];" /* Set up counter */
"mfmsr %[msr];" /* Save MSR */
"li %[tmp],0x20;" /* Disable IMMU */
"andc %[tmp],%[msr],%[tmp];"
"mtmsr %[tmp];"
"isync;"
MFPID(%[pid]) /* Save old PID */
"1:" MTPID(%[ctx]) /* Load user ctx */
"isync;"
"lbz %[tmp],0(%[uaddr]);" /* Load byte */
"addi %[uaddr],%[uaddr],1;"
"sync;"
MTPID(%[pid])
"isync;"
"stb %[tmp],0(%[kaddr]);" /* Store kernel byte */
"addi %[kaddr],%[kaddr],1;"
"or. %[tmp],%[tmp],%[tmp];"
"sync;"
"bdnzf eq,1b;" /* while(ctr-- && !zero) */
"mtmsr %[msr];" /* Restore MSR */
"isync;"
"mfctr %[resid];" /* Restore resid */
: [msr] "=&r" (msr), [pid] "=&r" (pid), [tmp] "=&r" (tmp),
[resid] "+r" (resid)
: [ctx] "r" (ctx), [uaddr] "b" (uaddr), [kaddr] "b" (kaddr)
: "cr0", "ctr");
curpcb->pcb_onfault = NULL;
if (done)
*done = len - resid;
if (resid == 0 && (char)tmp != '\0')
return ENAMETOOLONG;
else
return 0;
}
