369 lines
9.4 KiB
C
369 lines
9.4 KiB
C
/*
|
|
* Copyright (c) 1990 University of Utah.
|
|
* Copyright (c) 1991, 1993
|
|
* The Regents of the University of California. 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.
|
|
*
|
|
* 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.
|
|
*
|
|
* @(#)device_pager.c 8.1 (Berkeley) 6/11/93
|
|
* $Id: device_pager.c,v 1.6 1995/02/21 01:22:43 davidg Exp $
|
|
*/
|
|
|
|
/*
|
|
* Page to/from special files.
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/proc.h>
|
|
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_kern.h>
|
|
#include <vm/vm_page.h>
|
|
#include <vm/device_pager.h>
|
|
|
|
struct pagerlst dev_pager_list; /* list of managed devices */
|
|
struct pglist dev_pager_fakelist; /* list of available vm_page_t's */
|
|
|
|
#ifdef DEBUG
|
|
int dpagerdebug = 0;
|
|
|
|
#define DDB_FOLLOW 0x01
|
|
#define DDB_INIT 0x02
|
|
#define DDB_ALLOC 0x04
|
|
#define DDB_FAIL 0x08
|
|
#endif
|
|
|
|
static vm_pager_t dev_pager_alloc __P((caddr_t, vm_size_t, vm_prot_t, vm_offset_t));
|
|
static void dev_pager_dealloc __P((vm_pager_t));
|
|
static int dev_pager_getpage __P((vm_pager_t, vm_page_t, boolean_t));
|
|
static boolean_t dev_pager_haspage __P((vm_pager_t, vm_offset_t));
|
|
static void dev_pager_init __P((void));
|
|
static int dev_pager_putpage __P((vm_pager_t, vm_page_t, boolean_t));
|
|
static vm_page_t dev_pager_getfake __P((vm_offset_t));
|
|
static void dev_pager_putfake __P((vm_page_t));
|
|
|
|
struct pagerops devicepagerops = {
|
|
dev_pager_init,
|
|
dev_pager_alloc,
|
|
dev_pager_dealloc,
|
|
dev_pager_getpage,
|
|
0,
|
|
dev_pager_putpage,
|
|
0,
|
|
dev_pager_haspage
|
|
};
|
|
|
|
static void
|
|
dev_pager_init()
|
|
{
|
|
#ifdef DEBUG
|
|
if (dpagerdebug & DDB_FOLLOW)
|
|
printf("dev_pager_init()\n");
|
|
#endif
|
|
TAILQ_INIT(&dev_pager_list);
|
|
TAILQ_INIT(&dev_pager_fakelist);
|
|
}
|
|
|
|
static vm_pager_t
|
|
dev_pager_alloc(handle, size, prot, foff)
|
|
caddr_t handle;
|
|
vm_size_t size;
|
|
vm_prot_t prot;
|
|
vm_offset_t foff;
|
|
{
|
|
dev_t dev;
|
|
vm_pager_t pager;
|
|
int (*mapfunc) ();
|
|
vm_object_t object;
|
|
dev_pager_t devp;
|
|
unsigned int npages, off;
|
|
|
|
#ifdef DEBUG
|
|
if (dpagerdebug & DDB_FOLLOW)
|
|
printf("dev_pager_alloc(%x, %x, %x, %x)\n",
|
|
handle, size, prot, foff);
|
|
#endif
|
|
#ifdef DIAGNOSTIC
|
|
/*
|
|
* Pageout to device, should never happen.
|
|
*/
|
|
if (handle == NULL)
|
|
panic("dev_pager_alloc called");
|
|
#endif
|
|
|
|
/*
|
|
* Make sure this device can be mapped.
|
|
*/
|
|
dev = (dev_t) (u_long) handle;
|
|
mapfunc = cdevsw[major(dev)].d_mmap;
|
|
if (mapfunc == NULL || mapfunc == enodev || mapfunc == nullop)
|
|
return (NULL);
|
|
|
|
/*
|
|
* Offset should be page aligned.
|
|
*/
|
|
if (foff & (PAGE_SIZE - 1))
|
|
return (NULL);
|
|
|
|
/*
|
|
* Check that the specified range of the device allows the desired
|
|
* protection.
|
|
*
|
|
* XXX assumes VM_PROT_* == PROT_*
|
|
*/
|
|
npages = atop(round_page(size));
|
|
for (off = foff; npages--; off += PAGE_SIZE)
|
|
if ((*mapfunc) (dev, off, (int) prot) == -1)
|
|
return (NULL);
|
|
|
|
/*
|
|
* Look up pager, creating as necessary.
|
|
*/
|
|
top:
|
|
pager = vm_pager_lookup(&dev_pager_list, handle);
|
|
if (pager == NULL) {
|
|
/*
|
|
* Allocate and initialize pager structs
|
|
*/
|
|
pager = (vm_pager_t) malloc(sizeof *pager, M_VMPAGER, M_WAITOK);
|
|
if (pager == NULL)
|
|
return (NULL);
|
|
devp = (dev_pager_t) malloc(sizeof *devp, M_VMPGDATA, M_WAITOK);
|
|
if (devp == NULL) {
|
|
free((caddr_t) pager, M_VMPAGER);
|
|
return (NULL);
|
|
}
|
|
pager->pg_handle = handle;
|
|
pager->pg_ops = &devicepagerops;
|
|
pager->pg_type = PG_DEVICE;
|
|
pager->pg_data = (caddr_t) devp;
|
|
TAILQ_INIT(&devp->devp_pglist);
|
|
/*
|
|
* Allocate object and associate it with the pager.
|
|
*/
|
|
object = devp->devp_object = vm_object_allocate(0);
|
|
object->flags &= ~OBJ_INTERNAL;
|
|
vm_object_enter(object, pager);
|
|
object->pager = pager;
|
|
/*
|
|
* Finally, put it on the managed list so other can find it.
|
|
* First we re-lookup in case someone else beat us to this
|
|
* point (due to blocking in the various mallocs). If so, we
|
|
* free everything and start over.
|
|
*/
|
|
if (vm_pager_lookup(&dev_pager_list, handle)) {
|
|
free((caddr_t) devp, M_VMPGDATA);
|
|
free((caddr_t) pager, M_VMPAGER);
|
|
goto top;
|
|
}
|
|
TAILQ_INSERT_TAIL(&dev_pager_list, pager, pg_list);
|
|
#ifdef DEBUG
|
|
if (dpagerdebug & DDB_ALLOC) {
|
|
printf("dev_pager_alloc: pager %x devp %x object %x\n",
|
|
pager, devp, object);
|
|
vm_object_print(object, FALSE);
|
|
}
|
|
#endif
|
|
} else {
|
|
/*
|
|
* Gain a reference to the object.
|
|
*/
|
|
object = vm_object_lookup(pager);
|
|
#ifdef DIAGNOSTIC
|
|
devp = (dev_pager_t) pager->pg_data;
|
|
if (object != devp->devp_object)
|
|
panic("dev_pager_setup: bad object");
|
|
#endif
|
|
}
|
|
return (pager);
|
|
}
|
|
|
|
static void
|
|
dev_pager_dealloc(pager)
|
|
vm_pager_t pager;
|
|
{
|
|
dev_pager_t devp;
|
|
vm_object_t object;
|
|
vm_page_t m;
|
|
|
|
#ifdef DEBUG
|
|
if (dpagerdebug & DDB_FOLLOW)
|
|
printf("dev_pager_dealloc(%x)\n", pager);
|
|
#endif
|
|
TAILQ_REMOVE(&dev_pager_list, pager, pg_list);
|
|
/*
|
|
* Get the object. Note: cannot use vm_object_lookup since object has
|
|
* already been removed from the hash chain.
|
|
*/
|
|
devp = (dev_pager_t) pager->pg_data;
|
|
object = devp->devp_object;
|
|
#ifdef DEBUG
|
|
if (dpagerdebug & DDB_ALLOC)
|
|
printf("dev_pager_dealloc: devp %x object %x\n", devp, object);
|
|
#endif
|
|
/*
|
|
* Free up our fake pages.
|
|
*/
|
|
while ((m = devp->devp_pglist.tqh_first) != 0) {
|
|
TAILQ_REMOVE(&devp->devp_pglist, m, pageq);
|
|
dev_pager_putfake(m);
|
|
}
|
|
free((caddr_t) devp, M_VMPGDATA);
|
|
free((caddr_t) pager, M_VMPAGER);
|
|
}
|
|
|
|
static int
|
|
dev_pager_getpage(pager, m, sync)
|
|
vm_pager_t pager;
|
|
vm_page_t m;
|
|
boolean_t sync;
|
|
{
|
|
register vm_object_t object;
|
|
vm_offset_t offset, paddr;
|
|
vm_page_t page;
|
|
dev_t dev;
|
|
int s;
|
|
int (*mapfunc) (), prot;
|
|
|
|
#ifdef DEBUG
|
|
if (dpagerdebug & DDB_FOLLOW)
|
|
printf("dev_pager_getpage(%x, %x)\n", pager, m);
|
|
#endif
|
|
|
|
object = m->object;
|
|
dev = (dev_t) (u_long) pager->pg_handle;
|
|
offset = m->offset + object->paging_offset;
|
|
prot = PROT_READ; /* XXX should pass in? */
|
|
mapfunc = cdevsw[major(dev)].d_mmap;
|
|
|
|
if (mapfunc == NULL || mapfunc == enodev || mapfunc == nullop)
|
|
panic("dev_pager_getpage: no map function");
|
|
|
|
paddr = pmap_phys_address((*mapfunc) ((dev_t) dev, (int) offset, prot));
|
|
#ifdef DIAGNOSTIC
|
|
if (paddr == -1)
|
|
panic("dev_pager_getpage: map function returns error");
|
|
#endif
|
|
/*
|
|
* Replace the passed in page with our own fake page and free up the
|
|
* original.
|
|
*/
|
|
page = dev_pager_getfake(paddr);
|
|
TAILQ_INSERT_TAIL(&((dev_pager_t) pager->pg_data)->devp_pglist,
|
|
page, pageq);
|
|
vm_object_lock(object);
|
|
vm_page_lock_queues();
|
|
PAGE_WAKEUP(m);
|
|
vm_page_free(m);
|
|
vm_page_unlock_queues();
|
|
s = splhigh();
|
|
vm_page_insert(page, object, offset);
|
|
splx(s);
|
|
if (offset + PAGE_SIZE > object->size)
|
|
object->size = offset + PAGE_SIZE; /* XXX anal */
|
|
vm_object_unlock(object);
|
|
|
|
return (VM_PAGER_OK);
|
|
}
|
|
|
|
static int
|
|
dev_pager_putpage(pager, m, sync)
|
|
vm_pager_t pager;
|
|
vm_page_t m;
|
|
boolean_t sync;
|
|
{
|
|
#ifdef DEBUG
|
|
if (dpagerdebug & DDB_FOLLOW)
|
|
printf("dev_pager_putpage(%x, %x)\n", pager, m);
|
|
#endif
|
|
if (pager == NULL)
|
|
return 0;
|
|
panic("dev_pager_putpage called");
|
|
}
|
|
|
|
static boolean_t
|
|
dev_pager_haspage(pager, offset)
|
|
vm_pager_t pager;
|
|
vm_offset_t offset;
|
|
{
|
|
#ifdef DEBUG
|
|
if (dpagerdebug & DDB_FOLLOW)
|
|
printf("dev_pager_haspage(%x, %x)\n", pager, offset);
|
|
#endif
|
|
return (TRUE);
|
|
}
|
|
|
|
static vm_page_t
|
|
dev_pager_getfake(paddr)
|
|
vm_offset_t paddr;
|
|
{
|
|
vm_page_t m;
|
|
int i;
|
|
|
|
if (dev_pager_fakelist.tqh_first == NULL) {
|
|
m = (vm_page_t) malloc(PAGE_SIZE * 2, M_VMPGDATA, M_WAITOK);
|
|
for (i = (PAGE_SIZE * 2) / sizeof(*m); i > 0; i--) {
|
|
TAILQ_INSERT_TAIL(&dev_pager_fakelist, m, pageq);
|
|
m++;
|
|
}
|
|
}
|
|
m = dev_pager_fakelist.tqh_first;
|
|
TAILQ_REMOVE(&dev_pager_fakelist, m, pageq);
|
|
|
|
m->flags = PG_BUSY | PG_FICTITIOUS;
|
|
m->dirty = 0;
|
|
m->valid = VM_PAGE_BITS_ALL;
|
|
m->busy = 0;
|
|
m->bmapped = 0;
|
|
|
|
m->wire_count = 1;
|
|
m->phys_addr = paddr;
|
|
|
|
return (m);
|
|
}
|
|
|
|
static void
|
|
dev_pager_putfake(m)
|
|
vm_page_t m;
|
|
{
|
|
#ifdef DIAGNOSTIC
|
|
if (!(m->flags & PG_FICTITIOUS))
|
|
panic("dev_pager_putfake: bad page");
|
|
#endif
|
|
TAILQ_INSERT_TAIL(&dev_pager_fakelist, m, pageq);
|
|
}
|