freebsd-dev/sys/powerpc/aim/vm_machdep.c
Matt Jacob 22883e3c68 Fix problem where a user buffer outside of the area being tested
will be corrupted.

PR:		29194
Obtained from:	Tor.Egge@fast.no
MFC after:	2 weeks
2001-10-02 18:34:20 +00:00

316 lines
8.0 KiB
C

/*-
* Copyright (c) 1982, 1986 The Regents of the University of California.
* Copyright (c) 1989, 1990 William Jolitz
* Copyright (c) 1994 John Dyson
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department, and William Jolitz.
*
* 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 by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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.
*
* from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91
* Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$
* $FreeBSD$
*/
/*
* Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Chris G. Demetriou
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/mutex.h>
#include <sys/vnode.h>
#include <sys/vmmeter.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/unistd.h>
#include <machine/clock.h>
#include <machine/cpu.h>
#include <machine/fpu.h>
#include <machine/md_var.h>
#include <dev/ofw/openfirm.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <sys/lock.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_extern.h>
#include <sys/user.h>
/*
* quick version of vm_fault
*/
int
vm_fault_quick(v, prot)
caddr_t v;
int prot;
{
int r;
if (prot & VM_PROT_WRITE)
r = subyte(v, fubyte(v));
else
r = fubyte(v);
return(r);
}
/*
* Finish a fork operation, with process p2 nearly set up.
* Copy and update the pcb, set up the stack so that the child
* ready to run and return to user mode.
*/
void
cpu_fork(td1, p2, flags)
register struct thread *td1;
register struct proc *p2;
int flags;
{
/* XXX: coming soon... */
}
/*
* Intercept the return address from a freshly forked process that has NOT
* been scheduled yet.
*
* This is needed to make kernel threads stay in kernel mode.
*/
void
cpu_set_fork_handler(td, func, arg)
struct thread *td;
void (*func) __P((void *));
void *arg;
{
/*
* Note that the trap frame follows the args, so the function
* is really called like this: func(arg, frame);
*/
#if 0 /* XXX */
td->p_addr->u_pcb.pcb_context[0] = (u_long) func;
td->p_addr->u_pcb.pcb_context[2] = (u_long) arg;
#endif
}
/*
* cpu_exit is called as the last action during exit.
* We release the address space of the process, block interrupts,
* and call switch_exit. switch_exit switches to proc0's PCB and stack,
* then jumps into the middle of cpu_switch, as if it were switching
* from proc0.
*/
void
cpu_exit(td)
register struct thread *td;
{
}
void
cpu_wait(td)
struct proc *td;
{
}
/* Temporary helper */
void
cpu_throw(void)
{
cpu_switch();
panic("cpu_throw() didn't");
}
/*
* Dump the machine specific header information at the start of a core dump.
*/
int
cpu_coredump(td, vp, cred)
struct thread *td;
struct vnode *vp;
struct ucred *cred;
{
struct proc *p = td->td_proc;
return (vn_rdwr(UIO_WRITE, vp, (caddr_t)p->p_uarea, ctob(UAREA_PAGES),
(off_t)0, UIO_SYSSPACE, IO_UNIT, cred, (int *)NULL, p));
}
/*
* Map an IO request into kernel virtual address space.
*
* All requests are (re)mapped into kernel VA space.
* Notice that we use b_bufsize for the size of the buffer
* to be mapped. b_bcount might be modified by the driver.
*/
void
vmapbuf(bp)
register struct buf *bp;
{
register caddr_t addr, v, kva;
vm_offset_t pa;
GIANT_REQUIRED;
if ((bp->b_flags & B_PHYS) == 0)
panic("vmapbuf");
for (v = bp->b_saveaddr, addr = (caddr_t)trunc_page(bp->b_data);
addr < bp->b_data + bp->b_bufsize;
addr += PAGE_SIZE, v += PAGE_SIZE) {
/*
* Do the vm_fault if needed; do the copy-on-write thing
* when reading stuff off device into memory.
*/
vm_fault_quick((addr >= bp->b_data) ? addr : bp->b_data,
(bp->b_iocmd == BIO_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ);
pa = trunc_page(pmap_kextract((vm_offset_t) addr));
if (pa == 0)
panic("vmapbuf: page not present");
vm_page_hold(PHYS_TO_VM_PAGE(pa));
pmap_kenter((vm_offset_t) v, pa);
}
kva = bp->b_saveaddr;
bp->b_saveaddr = bp->b_data;
bp->b_data = kva + (((vm_offset_t) bp->b_data) & PAGE_MASK);
}
/*
* Free the io map PTEs associated with this IO operation.
* We also invalidate the TLB entries and restore the original b_addr.
*/
void
vunmapbuf(bp)
register struct buf *bp;
{
register caddr_t addr;
vm_offset_t pa;
GIANT_REQUIRED;
if ((bp->b_flags & B_PHYS) == 0)
panic("vunmapbuf");
for (addr = (caddr_t)trunc_page(bp->b_data);
addr < bp->b_data + bp->b_bufsize;
addr += PAGE_SIZE) {
pa = trunc_page(pmap_kextract((vm_offset_t) addr));
pmap_kremove((vm_offset_t) addr);
vm_page_unhold(PHYS_TO_VM_PAGE(pa));
}
bp->b_data = bp->b_saveaddr;
}
/*
* Reset back to firmware.
*/
void
cpu_reset()
{
OF_exit();
}
int
grow_stack(p, sp)
struct proc *p;
size_t sp;
{
int rv;
rv = vm_map_growstack (p, sp);
if (rv != KERN_SUCCESS)
return (0);
return (1);
}
/*
* Software interrupt handler for queued VM system processing.
*/
void
swi_vm(void *dummy)
{
#if 0 /* XXX: Don't have busdma stuff yet */
if (busdma_swi_pending != 0)
busdma_swi();
#endif
}
/*
* Tell whether this address is in some physical memory region.
* Currently used by the kernel coredump code in order to avoid
* dumping the ``ISA memory hole'' which could cause indefinite hangs,
* or other unpredictable behaviour.
*/
int
is_physical_memory(addr)
vm_offset_t addr;
{
/*
* stuff other tests for known memory-mapped devices (PCI?)
* here
*/
return 1;
}