/*-
* 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/rwlock.h>
#include <sys/sx.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
#include <vm/vm_phys.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, struct ucred *);
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 *);
static void dev_pager_free_page(vm_object_t object, vm_page_t m);
/* list of device pager objects */
static struct pagerlst dev_pager_object_list;
/* protect list manipulation */
static struct mtx dev_pager_mtx;
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,
};
struct pagerops mgtdevicepagerops = {
.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 int old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
vm_ooffset_t foff, struct ucred *cred, u_short *color);
static void old_dev_pager_dtor(void *handle);
static int old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset,
int prot, vm_page_t *mres);
static struct cdev_pager_ops old_dev_pager_ops = {
.cdev_pg_ctor = old_dev_pager_ctor,
.cdev_pg_dtor = old_dev_pager_dtor,
.cdev_pg_fault = old_dev_pager_fault
};
static void
dev_pager_init()
{
TAILQ_INIT(&dev_pager_object_list);
mtx_init(&dev_pager_mtx, "dev_pager list", NULL, MTX_DEF);
}
vm_object_t
cdev_pager_lookup(void *handle)
{
vm_object_t object;
mtx_lock(&dev_pager_mtx);
object = vm_pager_object_lookup(&dev_pager_object_list, handle);
mtx_unlock(&dev_pager_mtx);
return (object);
}
vm_object_t
cdev_pager_allocate(void *handle, enum obj_type tp, struct cdev_pager_ops *ops,
vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred)
{
vm_object_t object, object1;
vm_pindex_t pindex;
u_short color;
if (tp != OBJT_DEVICE && tp != OBJT_MGTDEVICE)
return (NULL);
/*
* Offset should be page aligned.
*/
if (foff & PAGE_MASK)
return (NULL);
size = round_page(size);
pindex = OFF_TO_IDX(foff + size);
if (ops->cdev_pg_ctor(handle, size, prot, foff, cred, &color) != 0)
return (NULL);
mtx_lock(&dev_pager_mtx);
/*
* Look up pager, creating as necessary.
*/
object1 = NULL;
object = vm_pager_object_lookup(&dev_pager_object_list, handle);
if (object == NULL) {
/*
* Allocate object and associate it with the pager. Initialize
* the object's pg_color based upon the physical address of the
* device's memory.
*/
mtx_unlock(&dev_pager_mtx);
object1 = vm_object_allocate(tp, pindex);
object1->flags |= OBJ_COLORED;
object1->pg_color = color;
object1->handle = handle;
object1->un_pager.devp.ops = ops;
object1->un_pager.devp.dev = handle;
TAILQ_INIT(&object1->un_pager.devp.devp_pglist);
mtx_lock(&dev_pager_mtx);
object = vm_pager_object_lookup(&dev_pager_object_list, handle);
if (object != NULL) {
/*
* We raced with other thread while allocating object.
*/
if (pindex > object->size)
object->size = pindex;
KASSERT(object->type == tp,
("Inconsistent device pager type %p %d", object, tp));
} else {
object = object1;
object1 = NULL;
object->handle = handle;
TAILQ_INSERT_TAIL(&dev_pager_object_list, object,
pager_object_list);
}
} else {
if (pindex > object->size)
object->size = pindex;
KASSERT(object->type == tp,
("Inconsistent device pager type %p %d", object, tp));
}
mtx_unlock(&dev_pager_mtx);
if (object1 != NULL) {
object1->handle = object1;
mtx_lock(&dev_pager_mtx);
TAILQ_INSERT_TAIL(&dev_pager_object_list, object1,
pager_object_list);
mtx_unlock(&dev_pager_mtx);
vm_object_deallocate(object1);
}
return (object);
}
static vm_object_t
dev_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot,
vm_ooffset_t foff, struct ucred *cred)
{
return (cdev_pager_allocate(handle, OBJT_DEVICE, &old_dev_pager_ops,
size, prot, foff, cred));
}
void
cdev_pager_free_page(vm_object_t object, vm_page_t m)
{
VM_OBJECT_ASSERT_WLOCKED(object);
if (object->type == OBJT_MGTDEVICE) {
KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("unmanaged %p", m));
pmap_remove_all(m);
vm_page_lock(m);
vm_page_remove(m);
vm_page_unlock(m);
} else if (object->type == OBJT_DEVICE)
dev_pager_free_page(object, m);
}
static void
dev_pager_free_page(vm_object_t object, vm_page_t m)
{
VM_OBJECT_ASSERT_WLOCKED(object);
KASSERT((object->type == OBJT_DEVICE &&
(m->oflags & VPO_UNMANAGED) != 0),
("Managed device or page obj %p m %p", object, m));
TAILQ_REMOVE(&object->un_pager.devp.devp_pglist, m, plinks.q);
vm_page_putfake(m);
}
static void
dev_pager_dealloc(object)
vm_object_t object;
{
vm_page_t m;
VM_OBJECT_WUNLOCK(object);
object->un_pager.devp.ops->cdev_pg_dtor(object->un_pager.devp.dev);
mtx_lock(&dev_pager_mtx);
TAILQ_REMOVE(&dev_pager_object_list, object, pager_object_list);
mtx_unlock(&dev_pager_mtx);
VM_OBJECT_WLOCK(object);
if (object->type == OBJT_DEVICE) {
/*
* Free up our fake pages.
*/
while ((m = TAILQ_FIRST(&object->un_pager.devp.devp_pglist))
!= NULL)
dev_pager_free_page(object, m);
}
}
static int
dev_pager_getpages(vm_object_t object, vm_page_t *ma, int count, int reqpage)
{
int error, i;
VM_OBJECT_ASSERT_WLOCKED(object);
error = object->un_pager.devp.ops->cdev_pg_fault(object,
IDX_TO_OFF(ma[reqpage]->pindex), PROT_READ, &ma[reqpage]);
VM_OBJECT_ASSERT_WLOCKED(object);
for (i = 0; i < count; i++) {
if (i != reqpage) {
vm_page_lock(ma[i]);
vm_page_free(ma[i]);
vm_page_unlock(ma[i]);
}
}
if (error == VM_PAGER_OK) {
KASSERT((object->type == OBJT_DEVICE &&
(ma[reqpage]->oflags & VPO_UNMANAGED) != 0) ||
(object->type == OBJT_MGTDEVICE &&
(ma[reqpage]->oflags & VPO_UNMANAGED) == 0),
("Wrong page type %p %p", ma[reqpage], object));
if (object->type == OBJT_DEVICE) {
TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist,
ma[reqpage], plinks.q);
}
}
return (error);
}
static int
old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset, int prot,
vm_page_t *mres)
{
vm_pindex_t pidx;
vm_paddr_t paddr;
vm_page_t m_paddr, page;
struct cdev *dev;
struct cdevsw *csw;
struct file *fpop;
struct thread *td;
vm_memattr_t memattr;
int ref, ret;
pidx = OFF_TO_IDX(offset);
memattr = object->memattr;
VM_OBJECT_WUNLOCK(object);
dev = object->handle;
csw = dev_refthread(dev, &ref);
if (csw == NULL) {
VM_OBJECT_WLOCK(object);
return (VM_PAGER_FAIL);
}
td = curthread;
fpop = td->td_fpop;
td->td_fpop = NULL;
ret = csw->d_mmap(dev, offset, &paddr, prot, &memattr);
td->td_fpop = fpop;
dev_relthread(dev, ref);
if (ret != 0) {
printf(
"WARNING: dev_pager_getpage: map function returns error %d", ret);
VM_OBJECT_WLOCK(object);
return (VM_PAGER_FAIL);
}
/* If "paddr" is a real page, perform a sanity check on "memattr". */
if ((m_paddr = vm_phys_paddr_to_vm_page(paddr)) != NULL &&
pmap_page_get_memattr(m_paddr) != memattr) {
memattr = pmap_page_get_memattr(m_paddr);
printf(
"WARNING: A device driver has set \"memattr\" inconsistently.\n");
}
if (((*mres)->flags & PG_FICTITIOUS) != 0) {
/*
* If the passed in result page is a fake page, update it with
* the new physical address.
*/
page = *mres;
VM_OBJECT_WLOCK(object);
vm_page_updatefake(page, paddr, memattr);
} else {
/*
* Replace the passed in reqpage page with our own fake page and
* free up the all of the original pages.
*/
page = vm_page_getfake(paddr, memattr);
VM_OBJECT_WLOCK(object);
if (vm_page_replace(page, object, (*mres)->pindex) != *mres)
panic("old_dev_pager_fault: invalid page replacement");
vm_page_lock(*mres);
vm_page_free(*mres);
vm_page_unlock(*mres);
*mres = page;
}
page->valid = VM_PAGE_BITS_ALL;
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 int
old_dev_pager_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
vm_ooffset_t foff, struct ucred *cred, u_short *color)
{
struct cdev *dev;
struct cdevsw *csw;
vm_memattr_t dummy;
vm_ooffset_t off;
vm_paddr_t paddr;
unsigned int npages;
int ref;
/*
* Make sure this device can be mapped.
*/
dev = handle;
csw = dev_refthread(dev, &ref);
if (csw == NULL)
return (ENXIO);
/*
* Check that the specified range of the device allows the desired
* protection.
*
* XXX assumes VM_PROT_* == PROT_*
*/
npages = OFF_TO_IDX(size);
paddr = 0; /* Make paddr initialized for the case of size == 0. */
for (off = foff; npages--; off += PAGE_SIZE) {
if (csw->d_mmap(dev, off, &paddr, (int)prot, &dummy) != 0) {
dev_relthread(dev, ref);
return (EINVAL);
}
}
dev_ref(dev);
dev_relthread(dev, ref);
*color = atop(paddr) - OFF_TO_IDX(off - PAGE_SIZE);
return (0);
}
static void
old_dev_pager_dtor(void *handle)
{
dev_rel(handle);
}
