327 lines
8.1 KiB
C
327 lines
8.1 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.
|
|
* 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
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/sx.h>
|
|
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_object.h>
|
|
#include <vm/vm_page.h>
|
|
#include <vm/vm_pager.h>
|
|
#include <vm/uma.h>
|
|
|
|
static void dev_pager_init(void);
|
|
static vm_object_t dev_pager_alloc(void *, vm_ooffset_t, vm_prot_t,
|
|
vm_ooffset_t);
|
|
static void dev_pager_dealloc(vm_object_t);
|
|
static int dev_pager_getpages(vm_object_t, vm_page_t *, int, int);
|
|
static void dev_pager_putpages(vm_object_t, vm_page_t *, int,
|
|
boolean_t, int *);
|
|
static boolean_t dev_pager_haspage(vm_object_t, vm_pindex_t, int *,
|
|
int *);
|
|
|
|
/* list of device pager objects */
|
|
static struct pagerlst dev_pager_object_list;
|
|
/* protect against object creation */
|
|
static struct sx dev_pager_sx;
|
|
/* protect list manipulation */
|
|
static struct mtx dev_pager_mtx;
|
|
|
|
|
|
static uma_zone_t fakepg_zone;
|
|
|
|
static vm_page_t dev_pager_getfake(vm_paddr_t);
|
|
static void dev_pager_putfake(vm_page_t);
|
|
static void dev_pager_updatefake(vm_page_t, vm_paddr_t);
|
|
|
|
struct pagerops devicepagerops = {
|
|
.pgo_init = dev_pager_init,
|
|
.pgo_alloc = dev_pager_alloc,
|
|
.pgo_dealloc = dev_pager_dealloc,
|
|
.pgo_getpages = dev_pager_getpages,
|
|
.pgo_putpages = dev_pager_putpages,
|
|
.pgo_haspage = dev_pager_haspage,
|
|
};
|
|
|
|
static void
|
|
dev_pager_init()
|
|
{
|
|
TAILQ_INIT(&dev_pager_object_list);
|
|
sx_init(&dev_pager_sx, "dev_pager create");
|
|
mtx_init(&dev_pager_mtx, "dev_pager list", NULL, MTX_DEF);
|
|
fakepg_zone = uma_zcreate("DP fakepg", sizeof(struct vm_page),
|
|
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
|
|
UMA_ZONE_NOFREE|UMA_ZONE_VM);
|
|
}
|
|
|
|
/*
|
|
* MPSAFE
|
|
*/
|
|
static vm_object_t
|
|
dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff)
|
|
{
|
|
struct cdev *dev;
|
|
vm_object_t object;
|
|
vm_pindex_t pindex;
|
|
unsigned int npages;
|
|
vm_paddr_t paddr;
|
|
vm_offset_t off;
|
|
struct cdevsw *csw;
|
|
|
|
/*
|
|
* Offset should be page aligned.
|
|
*/
|
|
if (foff & PAGE_MASK)
|
|
return (NULL);
|
|
|
|
size = round_page(size);
|
|
pindex = OFF_TO_IDX(foff + size);
|
|
|
|
/*
|
|
* Make sure this device can be mapped.
|
|
*/
|
|
dev = handle;
|
|
csw = dev_refthread(dev);
|
|
if (csw == NULL)
|
|
return (NULL);
|
|
mtx_lock(&Giant);
|
|
|
|
/*
|
|
* Check that the specified range of the device allows the desired
|
|
* protection.
|
|
*
|
|
* XXX assumes VM_PROT_* == PROT_*
|
|
*/
|
|
npages = OFF_TO_IDX(size);
|
|
for (off = foff; npages--; off += PAGE_SIZE)
|
|
if ((*csw->d_mmap)(dev, off, &paddr, (int)prot) != 0) {
|
|
mtx_unlock(&Giant);
|
|
dev_relthread(dev);
|
|
return (NULL);
|
|
}
|
|
|
|
/*
|
|
* Lock to prevent object creation race condition.
|
|
*/
|
|
sx_xlock(&dev_pager_sx);
|
|
|
|
/*
|
|
* Look up pager, creating as necessary.
|
|
*/
|
|
object = vm_pager_object_lookup(&dev_pager_object_list, handle);
|
|
if (object == NULL) {
|
|
/*
|
|
* Allocate object and associate it with the pager.
|
|
*/
|
|
object = vm_object_allocate(OBJT_DEVICE, pindex);
|
|
object->handle = handle;
|
|
TAILQ_INIT(&object->un_pager.devp.devp_pglist);
|
|
mtx_lock(&dev_pager_mtx);
|
|
TAILQ_INSERT_TAIL(&dev_pager_object_list, object, pager_object_list);
|
|
mtx_unlock(&dev_pager_mtx);
|
|
} else {
|
|
/*
|
|
* Gain a reference to the object.
|
|
*/
|
|
vm_object_reference(object);
|
|
if (pindex > object->size)
|
|
object->size = pindex;
|
|
}
|
|
|
|
sx_xunlock(&dev_pager_sx);
|
|
mtx_unlock(&Giant);
|
|
dev_relthread(dev);
|
|
return (object);
|
|
}
|
|
|
|
static void
|
|
dev_pager_dealloc(object)
|
|
vm_object_t object;
|
|
{
|
|
vm_page_t m;
|
|
|
|
mtx_lock(&dev_pager_mtx);
|
|
TAILQ_REMOVE(&dev_pager_object_list, object, pager_object_list);
|
|
mtx_unlock(&dev_pager_mtx);
|
|
/*
|
|
* Free up our fake pages.
|
|
*/
|
|
while ((m = TAILQ_FIRST(&object->un_pager.devp.devp_pglist)) != 0) {
|
|
TAILQ_REMOVE(&object->un_pager.devp.devp_pglist, m, pageq);
|
|
dev_pager_putfake(m);
|
|
}
|
|
}
|
|
|
|
static int
|
|
dev_pager_getpages(object, m, count, reqpage)
|
|
vm_object_t object;
|
|
vm_page_t *m;
|
|
int count;
|
|
int reqpage;
|
|
{
|
|
vm_pindex_t offset;
|
|
vm_paddr_t paddr;
|
|
vm_page_t page;
|
|
struct cdev *dev;
|
|
int i, ret;
|
|
int prot;
|
|
struct cdevsw *csw;
|
|
|
|
VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
|
|
dev = object->handle;
|
|
offset = m[reqpage]->pindex;
|
|
VM_OBJECT_UNLOCK(object);
|
|
csw = dev_refthread(dev);
|
|
if (csw == NULL)
|
|
panic("dev_pager_getpage: no cdevsw");
|
|
mtx_lock(&Giant);
|
|
prot = PROT_READ; /* XXX should pass in? */
|
|
|
|
ret = (*csw->d_mmap)(dev, (vm_offset_t)offset << PAGE_SHIFT, &paddr, prot);
|
|
KASSERT(ret == 0, ("dev_pager_getpage: map function returns error"));
|
|
mtx_unlock(&Giant);
|
|
dev_relthread(dev);
|
|
|
|
if ((m[reqpage]->flags & PG_FICTITIOUS) != 0) {
|
|
/*
|
|
* If the passed in reqpage page is a fake page, update it with
|
|
* the new physical address.
|
|
*/
|
|
VM_OBJECT_LOCK(object);
|
|
dev_pager_updatefake(m[reqpage], paddr);
|
|
if (count > 1) {
|
|
vm_page_lock_queues();
|
|
for (i = 0; i < count; i++) {
|
|
if (i != reqpage)
|
|
vm_page_free(m[i]);
|
|
}
|
|
vm_page_unlock_queues();
|
|
}
|
|
} else {
|
|
/*
|
|
* Replace the passed in reqpage page with our own fake page and
|
|
* free up the all of the original pages.
|
|
*/
|
|
page = dev_pager_getfake(paddr);
|
|
VM_OBJECT_LOCK(object);
|
|
TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist, page, pageq);
|
|
vm_page_lock_queues();
|
|
for (i = 0; i < count; i++)
|
|
vm_page_free(m[i]);
|
|
vm_page_unlock_queues();
|
|
vm_page_insert(page, object, offset);
|
|
m[reqpage] = page;
|
|
}
|
|
|
|
return (VM_PAGER_OK);
|
|
}
|
|
|
|
static void
|
|
dev_pager_putpages(object, m, count, sync, rtvals)
|
|
vm_object_t object;
|
|
vm_page_t *m;
|
|
int count;
|
|
boolean_t sync;
|
|
int *rtvals;
|
|
{
|
|
panic("dev_pager_putpage called");
|
|
}
|
|
|
|
static boolean_t
|
|
dev_pager_haspage(object, pindex, before, after)
|
|
vm_object_t object;
|
|
vm_pindex_t pindex;
|
|
int *before;
|
|
int *after;
|
|
{
|
|
if (before != NULL)
|
|
*before = 0;
|
|
if (after != NULL)
|
|
*after = 0;
|
|
return (TRUE);
|
|
}
|
|
|
|
static vm_page_t
|
|
dev_pager_getfake(paddr)
|
|
vm_paddr_t paddr;
|
|
{
|
|
vm_page_t m;
|
|
|
|
m = uma_zalloc(fakepg_zone, M_WAITOK);
|
|
|
|
m->flags = PG_BUSY | PG_FICTITIOUS;
|
|
m->valid = VM_PAGE_BITS_ALL;
|
|
m->dirty = 0;
|
|
m->busy = 0;
|
|
m->queue = PQ_NONE;
|
|
m->object = NULL;
|
|
|
|
m->wire_count = 1;
|
|
m->hold_count = 0;
|
|
m->phys_addr = paddr;
|
|
|
|
return (m);
|
|
}
|
|
|
|
static void
|
|
dev_pager_putfake(m)
|
|
vm_page_t m;
|
|
{
|
|
if (!(m->flags & PG_FICTITIOUS))
|
|
panic("dev_pager_putfake: bad page");
|
|
uma_zfree(fakepg_zone, m);
|
|
}
|
|
|
|
static void
|
|
dev_pager_updatefake(m, paddr)
|
|
vm_page_t m;
|
|
vm_paddr_t paddr;
|
|
{
|
|
if (!(m->flags & PG_FICTITIOUS))
|
|
panic("dev_pager_updatefake: bad page");
|
|
m->phys_addr = paddr;
|
|
m->valid = VM_PAGE_BITS_ALL;
|
|
}
|