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|
/*
* Mach Operating System
* Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University.
* Copyright (c) 1993,1994 The University of Utah and
* the Computer Systems Laboratory (CSL).
* All rights reserved.
*
* 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, THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF
* THIS SOFTWARE IN ITS "AS IS" CONDITION, AND DISCLAIM 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 Mellon
* the rights to redistribute these changes.
*/
/*
* File: vm/vm_kern.c
* Author: Avadis Tevanian, Jr., Michael Wayne Young
* Date: 1985
*
* Kernel memory management.
*/
#include <string.h>
#include <mach/kern_return.h>
#include <machine/locore.h>
#include <machine/vm_param.h>
#include <kern/assert.h>
#include <kern/debug.h>
#include <kern/lock.h>
#include <kern/slab.h>
#include <kern/thread.h>
#include <kern/printf.h>
#include <vm/pmap.h>
#include <vm/vm_fault.h>
#include <vm/vm_kern.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pageout.h>
/*
* Variables exported by this module.
*/
static struct vm_map kernel_map_store;
vm_map_t kernel_map = &kernel_map_store;
vm_map_t kernel_pageable_map;
/*
* projected_buffer_allocate
*
* Allocate a wired-down buffer shared between kernel and user task.
* Fresh, zero-filled memory is allocated.
* If persistence is false, this buffer can only be deallocated from
* user task using projected_buffer_deallocate, and deallocation
* from user task also deallocates the buffer from the kernel map.
* projected_buffer_collect is called from vm_map_deallocate to
* automatically deallocate projected buffers on task_deallocate.
* Sharing with more than one user task is achieved by using
* projected_buffer_map for the second and subsequent tasks.
* The user is precluded from manipulating the VM entry of this buffer
* (i.e. changing protection, inheritance or machine attributes).
*/
kern_return_t
projected_buffer_allocate(
vm_map_t map,
vm_size_t size,
int persistence,
vm_offset_t *kernel_p,
vm_offset_t *user_p,
vm_prot_t protection,
vm_inherit_t inheritance) /*Currently only VM_INHERIT_NONE supported*/
{
vm_object_t object;
vm_map_entry_t u_entry, k_entry;
vm_offset_t addr;
vm_size_t r_size;
kern_return_t kr;
if (map == VM_MAP_NULL || map == kernel_map)
return(KERN_INVALID_ARGUMENT);
/*
* Allocate a new object.
*/
size = round_page(size);
object = vm_object_allocate(size);
vm_map_lock(kernel_map);
kr = vm_map_find_entry(kernel_map, &addr, size, (vm_offset_t) 0,
VM_OBJECT_NULL, &k_entry);
if (kr != KERN_SUCCESS) {
vm_map_unlock(kernel_map);
vm_object_deallocate(object);
return kr;
}
k_entry->object.vm_object = object;
if (!persistence)
k_entry->projected_on = (vm_map_entry_t) -1;
/*Mark entry so as to automatically deallocate it when
last corresponding user entry is deallocated*/
vm_map_unlock(kernel_map);
*kernel_p = addr;
vm_map_lock(map);
kr = vm_map_find_entry(map, &addr, size, (vm_offset_t) 0,
VM_OBJECT_NULL, &u_entry);
if (kr != KERN_SUCCESS) {
vm_map_unlock(map);
vm_map_lock(kernel_map);
vm_map_entry_delete(kernel_map, k_entry);
vm_map_unlock(kernel_map);
vm_object_deallocate(object);
return kr;
}
u_entry->object.vm_object = object;
vm_object_reference(object);
u_entry->projected_on = k_entry;
/*Creates coupling with kernel mapping of the buffer, and
also guarantees that user cannot directly manipulate
buffer VM entry*/
u_entry->protection = protection;
u_entry->max_protection = protection;
u_entry->inheritance = inheritance;
vm_map_unlock(map);
*user_p = addr;
/*
* Allocate wired-down memory in the object,
* and enter it in the kernel pmap.
*/
kmem_alloc_pages(object, 0,
*kernel_p, *kernel_p + size,
VM_PROT_READ | VM_PROT_WRITE);
memset((void*) *kernel_p, 0, size); /*Zero fill*/
/* Set up physical mappings for user pmap */
pmap_pageable(map->pmap, *user_p, *user_p + size, FALSE);
for (r_size = 0; r_size < size; r_size += PAGE_SIZE) {
addr = pmap_extract(kernel_pmap, *kernel_p + r_size);
pmap_enter(map->pmap, *user_p + r_size, addr,
protection, TRUE);
}
return(KERN_SUCCESS);
}
/*
* projected_buffer_map
*
* Map an area of kernel memory onto a task's address space.
* No new memory is allocated; the area must previously exist in the
* kernel memory map.
*/
kern_return_t
projected_buffer_map(
vm_map_t map,
vm_offset_t kernel_addr,
vm_size_t size,
vm_offset_t *user_p,
vm_prot_t protection,
vm_inherit_t inheritance) /*Currently only VM_INHERIT_NONE supported*/
{
vm_map_entry_t u_entry, k_entry;
vm_offset_t physical_addr, user_addr;
vm_size_t r_size;
kern_return_t kr;
/*
* Find entry in kernel map
*/
size = round_page(size);
if (map == VM_MAP_NULL || map == kernel_map ||
!vm_map_lookup_entry(kernel_map, kernel_addr, &k_entry) ||
kernel_addr + size > k_entry->vme_end)
return(KERN_INVALID_ARGUMENT);
/*
* Create entry in user task
*/
vm_map_lock(map);
kr = vm_map_find_entry(map, &user_addr, size, (vm_offset_t) 0,
VM_OBJECT_NULL, &u_entry);
if (kr != KERN_SUCCESS) {
vm_map_unlock(map);
return kr;
}
u_entry->object.vm_object = k_entry->object.vm_object;
vm_object_reference(k_entry->object.vm_object);
u_entry->offset = kernel_addr - k_entry->vme_start + k_entry->offset;
u_entry->projected_on = k_entry;
/*Creates coupling with kernel mapping of the buffer, and
also guarantees that user cannot directly manipulate
buffer VM entry*/
u_entry->protection = protection;
u_entry->max_protection = protection;
u_entry->inheritance = inheritance;
u_entry->wired_count = k_entry->wired_count;
vm_map_unlock(map);
*user_p = user_addr;
/* Set up physical mappings for user pmap */
pmap_pageable(map->pmap, user_addr, user_addr + size,
!k_entry->wired_count);
for (r_size = 0; r_size < size; r_size += PAGE_SIZE) {
physical_addr = pmap_extract(kernel_pmap, kernel_addr + r_size);
pmap_enter(map->pmap, user_addr + r_size, physical_addr,
protection, k_entry->wired_count);
}
return(KERN_SUCCESS);
}
/*
* projected_buffer_deallocate
*
* Unmap projected buffer from task's address space.
* May also unmap buffer from kernel map, if buffer is not
* persistent and only the kernel reference remains.
*/
kern_return_t
projected_buffer_deallocate(
vm_map_t map,
vm_offset_t start,
vm_offset_t end)
{
vm_map_entry_t entry, k_entry;
if (map == VM_MAP_NULL || map == kernel_map)
return KERN_INVALID_ARGUMENT;
vm_map_lock(map);
if (!vm_map_lookup_entry(map, start, &entry) ||
end > entry->vme_end ||
/*Check corresponding kernel entry*/
(k_entry = entry->projected_on) == 0) {
vm_map_unlock(map);
return(KERN_INVALID_ARGUMENT);
}
/*Prepare for deallocation*/
if (entry->vme_start < start)
_vm_map_clip_start(&map->hdr, entry, start);
if (entry->vme_end > end)
_vm_map_clip_end(&map->hdr, entry, end);
if (map->first_free == entry) /*Adjust first_free hint*/
map->first_free = entry->vme_prev;
entry->projected_on = 0; /*Needed to allow deletion*/
entry->wired_count = 0; /*Avoid unwire fault*/
vm_map_entry_delete(map, entry);
vm_map_unlock(map);
/*Check if the buffer is not persistent and only the
kernel mapping remains, and if so delete it*/
vm_map_lock(kernel_map);
if (k_entry->projected_on == (vm_map_entry_t) -1 &&
k_entry->object.vm_object->ref_count == 1) {
if (kernel_map->first_free == k_entry)
kernel_map->first_free = k_entry->vme_prev;
k_entry->projected_on = 0; /*Allow unwire fault*/
vm_map_entry_delete(kernel_map, k_entry);
}
vm_map_unlock(kernel_map);
return(KERN_SUCCESS);
}
/*
* projected_buffer_collect
*
* Unmap all projected buffers from task's address space.
*/
kern_return_t
projected_buffer_collect(vm_map_t map)
{
vm_map_entry_t entry, next;
if (map == VM_MAP_NULL || map == kernel_map)
return(KERN_INVALID_ARGUMENT);
for (entry = vm_map_first_entry(map);
entry != vm_map_to_entry(map);
entry = next) {
next = entry->vme_next;
if (entry->projected_on != 0)
projected_buffer_deallocate(map, entry->vme_start, entry->vme_end);
}
return(KERN_SUCCESS);
}
/*
* projected_buffer_in_range
*
* Verifies whether a projected buffer exists in the address range
* given.
*/
boolean_t
projected_buffer_in_range(
vm_map_t map,
vm_offset_t start,
vm_offset_t end)
{
vm_map_entry_t entry;
if (map == VM_MAP_NULL || map == kernel_map)
return(FALSE);
/*Find first entry*/
if (!vm_map_lookup_entry(map, start, &entry))
entry = entry->vme_next;
while (entry != vm_map_to_entry(map) && entry->projected_on == 0 &&
entry->vme_start <= end) {
entry = entry->vme_next;
}
return(entry != vm_map_to_entry(map) && entry->vme_start <= end);
}
/*
* kmem_alloc:
*
* Allocate wired-down memory in the kernel's address map
* or a submap. The memory is not zero-filled.
*/
kern_return_t
kmem_alloc(
vm_map_t map,
vm_offset_t *addrp,
vm_size_t size)
{
vm_object_t object;
vm_map_entry_t entry;
vm_offset_t addr;
unsigned int attempts;
kern_return_t kr;
/*
* Allocate a new object. We must do this before locking
* the map, lest we risk deadlock with the default pager:
* device_read_alloc uses kmem_alloc,
* which tries to allocate an object,
* which uses kmem_alloc_wired to get memory,
* which blocks for pages.
* then the default pager needs to read a block
* to process a memory_object_data_write,
* and device_read_alloc calls kmem_alloc
* and deadlocks on the map lock.
*/
size = round_page(size);
object = vm_object_allocate(size);
attempts = 0;
retry:
vm_map_lock(map);
kr = vm_map_find_entry(map, &addr, size, (vm_offset_t) 0,
VM_OBJECT_NULL, &entry);
if (kr != KERN_SUCCESS) {
vm_map_unlock(map);
if (attempts == 0) {
attempts++;
slab_collect();
goto retry;
}
printf_once("no more room for kmem_alloc in %p\n", map);
vm_object_deallocate(object);
return kr;
}
entry->object.vm_object = object;
entry->offset = 0;
/*
* Since we have not given out this address yet,
* it is safe to unlock the map.
*/
vm_map_unlock(map);
/*
* Allocate wired-down memory in the kernel_object,
* for this entry, and enter it in the kernel pmap.
*/
kmem_alloc_pages(object, 0,
addr, addr + size,
VM_PROT_DEFAULT);
/*
* Return the memory, not zeroed.
*/
*addrp = addr;
return KERN_SUCCESS;
}
/*
* kmem_alloc_wired:
*
* Allocate wired-down memory in the kernel's address map
* or a submap. The memory is not zero-filled.
*
* The memory is allocated in the kernel_object.
* It may not be copied with vm_map_copy.
*/
kern_return_t
kmem_alloc_wired(
vm_map_t map,
vm_offset_t *addrp,
vm_size_t size)
{
vm_map_entry_t entry;
vm_offset_t offset;
vm_offset_t addr;
unsigned int attempts;
kern_return_t kr;
/*
* Use the kernel object for wired-down kernel pages.
* Assume that no region of the kernel object is
* referenced more than once. We want vm_map_find_entry
* to extend an existing entry if possible.
*/
size = round_page(size);
attempts = 0;
retry:
vm_map_lock(map);
kr = vm_map_find_entry(map, &addr, size, (vm_offset_t) 0,
kernel_object, &entry);
if (kr != KERN_SUCCESS) {
vm_map_unlock(map);
if (attempts == 0) {
attempts++;
slab_collect();
goto retry;
}
printf_once("no more room for kmem_alloc_wired in %p\n", map);
return kr;
}
/*
* Since we didn't know where the new region would
* start, we couldn't supply the correct offset into
* the kernel object. We only initialize the entry
* if we aren't extending an existing entry.
*/
offset = addr - VM_MIN_KERNEL_ADDRESS;
if (entry->object.vm_object == VM_OBJECT_NULL) {
vm_object_reference(kernel_object);
entry->object.vm_object = kernel_object;
entry->offset = offset;
}
/*
* Since we have not given out this address yet,
* it is safe to unlock the map.
*/
vm_map_unlock(map);
/*
* Allocate wired-down memory in the kernel_object,
* for this entry, and enter it in the kernel pmap.
*/
kmem_alloc_pages(kernel_object, offset,
addr, addr + size,
VM_PROT_DEFAULT);
/*
* Return the memory, not zeroed.
*/
*addrp = addr;
return KERN_SUCCESS;
}
/*
* kmem_alloc_aligned:
*
* Like kmem_alloc_wired, except that the memory is aligned.
* The size should be a power-of-2.
*/
kern_return_t
kmem_alloc_aligned(
vm_map_t map,
vm_offset_t *addrp,
vm_size_t size)
{
vm_map_entry_t entry;
vm_offset_t offset;
vm_offset_t addr;
unsigned int attempts;
kern_return_t kr;
if ((size & (size - 1)) != 0)
panic("kmem_alloc_aligned");
/*
* Use the kernel object for wired-down kernel pages.
* Assume that no region of the kernel object is
* referenced more than once. We want vm_map_find_entry
* to extend an existing entry if possible.
*/
size = round_page(size);
attempts = 0;
retry:
vm_map_lock(map);
kr = vm_map_find_entry(map, &addr, size, size - 1,
kernel_object, &entry);
if (kr != KERN_SUCCESS) {
vm_map_unlock(map);
if (attempts == 0) {
attempts++;
slab_collect();
goto retry;
}
printf_once("no more rooom for kmem_alloc_aligned in %p\n", map);
return kr;
}
/*
* Since we didn't know where the new region would
* start, we couldn't supply the correct offset into
* the kernel object. We only initialize the entry
* if we aren't extending an existing entry.
*/
offset = addr - VM_MIN_KERNEL_ADDRESS;
if (entry->object.vm_object == VM_OBJECT_NULL) {
vm_object_reference(kernel_object);
entry->object.vm_object = kernel_object;
entry->offset = offset;
}
/*
* Since we have not given out this address yet,
* it is safe to unlock the map.
*/
vm_map_unlock(map);
/*
* Allocate wired-down memory in the kernel_object,
* for this entry, and enter it in the kernel pmap.
*/
kmem_alloc_pages(kernel_object, offset,
addr, addr + size,
VM_PROT_DEFAULT);
/*
* Return the memory, not zeroed.
*/
*addrp = addr;
return KERN_SUCCESS;
}
/*
* kmem_alloc_pageable:
*
* Allocate pageable memory in the kernel's address map.
*/
kern_return_t
kmem_alloc_pageable(
vm_map_t map,
vm_offset_t *addrp,
vm_size_t size)
{
vm_offset_t addr;
kern_return_t kr;
addr = vm_map_min(map);
kr = vm_map_enter(map, &addr, round_page(size),
(vm_offset_t) 0, TRUE,
VM_OBJECT_NULL, (vm_offset_t) 0, FALSE,
VM_PROT_DEFAULT, VM_PROT_ALL, VM_INHERIT_DEFAULT);
if (kr != KERN_SUCCESS) {
printf_once("no more room for kmem_alloc_pageable in %p\n", map);
return kr;
}
*addrp = addr;
return KERN_SUCCESS;
}
/*
* kmem_free:
*
* Release a region of kernel virtual memory allocated
* with kmem_alloc, kmem_alloc_wired, or kmem_alloc_pageable,
* and return the physical pages associated with that region.
*/
void
kmem_free(
vm_map_t map,
vm_offset_t addr,
vm_size_t size)
{
kern_return_t kr;
kr = vm_map_remove(map, trunc_page(addr), round_page(addr + size));
if (kr != KERN_SUCCESS)
panic("kmem_free");
}
/*
* Allocate new wired pages in an object.
* The object is assumed to be mapped into the kernel map or
* a submap.
*/
void
kmem_alloc_pages(
vm_object_t object,
vm_offset_t offset,
vm_offset_t start,
vm_offset_t end,
vm_prot_t protection)
{
/*
* Mark the pmap region as not pageable.
*/
pmap_pageable(kernel_pmap, start, end, FALSE);
while (start < end) {
vm_page_t mem;
vm_object_lock(object);
/*
* Allocate a page
*/
while ((mem = vm_page_alloc(object, offset))
== VM_PAGE_NULL) {
vm_object_unlock(object);
VM_PAGE_WAIT((void (*)()) 0);
vm_object_lock(object);
}
/*
* Wire it down
*/
vm_page_lock_queues();
vm_page_wire(mem);
vm_page_unlock_queues();
vm_object_unlock(object);
/*
* Enter it in the kernel pmap
*/
PMAP_ENTER(kernel_pmap, start, mem,
protection, TRUE);
vm_object_lock(object);
PAGE_WAKEUP_DONE(mem);
vm_object_unlock(object);
start += PAGE_SIZE;
offset += PAGE_SIZE;
}
}
/*
* Remap wired pages in an object into a new region.
* The object is assumed to be mapped into the kernel map or
* a submap.
*/
void
kmem_remap_pages(
vm_object_t object,
vm_offset_t offset,
vm_offset_t start,
vm_offset_t end,
vm_prot_t protection)
{
/*
* Mark the pmap region as not pageable.
*/
pmap_pageable(kernel_pmap, start, end, FALSE);
while (start < end) {
vm_page_t mem;
vm_object_lock(object);
/*
* Find a page
*/
if ((mem = vm_page_lookup(object, offset)) == VM_PAGE_NULL)
panic("kmem_remap_pages");
/*
* Wire it down (again)
*/
vm_page_lock_queues();
vm_page_wire(mem);
vm_page_unlock_queues();
vm_object_unlock(object);
/*
* Enter it in the kernel pmap. The page isn't busy,
* but this shouldn't be a problem because it is wired.
*/
PMAP_ENTER(kernel_pmap, start, mem,
protection, TRUE);
start += PAGE_SIZE;
offset += PAGE_SIZE;
}
}
/*
* kmem_submap:
*
* Initializes a map to manage a subrange
* of the kernel virtual address space.
*
* Arguments are as follows:
*
* map Map to initialize
* parent Map to take range from
* size Size of range to find
* min, max Returned endpoints of map
* pageable Can the region be paged
*/
void
kmem_submap(
vm_map_t map,
vm_map_t parent,
vm_offset_t *min,
vm_offset_t *max,
vm_size_t size,
boolean_t pageable)
{
vm_offset_t addr;
kern_return_t kr;
size = round_page(size);
/*
* Need reference on submap object because it is internal
* to the vm_system. vm_object_enter will never be called
* on it (usual source of reference for vm_map_enter).
*/
vm_object_reference(vm_submap_object);
addr = vm_map_min(parent);
kr = vm_map_enter(parent, &addr, size,
(vm_offset_t) 0, TRUE,
vm_submap_object, (vm_offset_t) 0, FALSE,
VM_PROT_DEFAULT, VM_PROT_ALL, VM_INHERIT_DEFAULT);
if (kr != KERN_SUCCESS)
panic("kmem_submap");
pmap_reference(vm_map_pmap(parent));
vm_map_setup(map, vm_map_pmap(parent), addr, addr + size, pageable);
kr = vm_map_submap(parent, addr, addr + size, map);
if (kr != KERN_SUCCESS)
panic("kmem_submap");
*min = addr;
*max = addr + size;
}
/*
* kmem_init:
*
* Initialize the kernel's virtual memory map, taking
* into account all memory allocated up to this time.
*/
void kmem_init(
vm_offset_t start,
vm_offset_t end)
{
vm_map_setup(kernel_map, pmap_kernel(), VM_MIN_KERNEL_ADDRESS, end,
FALSE);
/*
* Reserve virtual memory allocated up to this time.
*/
if (start != VM_MIN_KERNEL_ADDRESS) {
kern_return_t rc;
vm_offset_t addr = VM_MIN_KERNEL_ADDRESS;
rc = vm_map_enter(kernel_map,
&addr, start - VM_MIN_KERNEL_ADDRESS,
(vm_offset_t) 0, TRUE,
VM_OBJECT_NULL, (vm_offset_t) 0, FALSE,
VM_PROT_DEFAULT, VM_PROT_ALL,
VM_INHERIT_DEFAULT);
if (rc)
panic("%s:%d: vm_map_enter failed (%d)\n", rc);
}
}
/*
* New and improved IO wiring support.
*/
/*
* kmem_io_map_copyout:
*
* Establish temporary mapping in designated map for the memory
* passed in. Memory format must be a page_list vm_map_copy.
* Mapping is READ-ONLY.
*/
kern_return_t
kmem_io_map_copyout(
vm_map_t map,
vm_offset_t *addr, /* actual addr of data */
vm_offset_t *alloc_addr, /* page aligned addr */
vm_size_t *alloc_size, /* size allocated */
vm_map_copy_t copy,
vm_size_t min_size) /* Do at least this much */
{
vm_offset_t myaddr, offset;
vm_size_t mysize, copy_size;
kern_return_t ret;
vm_page_t *page_list;
vm_map_copy_t new_copy;
int i;
assert(copy->type == VM_MAP_COPY_PAGE_LIST);
assert(min_size != 0);
/*
* Figure out the size in vm pages.
*/
min_size += copy->offset - trunc_page(copy->offset);
min_size = round_page(min_size);
mysize = round_page(copy->offset + copy->size) -
trunc_page(copy->offset);
/*
* If total size is larger than one page list and
* we don't have to do more than one page list, then
* only do one page list.
*
* XXX Could be much smarter about this ... like trimming length
* XXX if we need more than one page list but not all of them.
*/
copy_size = ptoa(copy->cpy_npages);
if (mysize > copy_size && copy_size > min_size)
mysize = copy_size;
/*
* Allocate some address space in the map (must be kernel
* space).
*/
myaddr = vm_map_min(map);
ret = vm_map_enter(map, &myaddr, mysize,
(vm_offset_t) 0, TRUE,
VM_OBJECT_NULL, (vm_offset_t) 0, FALSE,
VM_PROT_DEFAULT, VM_PROT_ALL, VM_INHERIT_DEFAULT);
if (ret != KERN_SUCCESS)
return(ret);
/*
* Tell the pmap module that this will be wired, and
* enter the mappings.
*/
pmap_pageable(vm_map_pmap(map), myaddr, myaddr + mysize, TRUE);
*addr = myaddr + (copy->offset - trunc_page(copy->offset));
*alloc_addr = myaddr;
*alloc_size = mysize;
offset = myaddr;
page_list = ©->cpy_page_list[0];
while (TRUE) {
for ( i = 0; i < copy->cpy_npages; i++, offset += PAGE_SIZE) {
PMAP_ENTER(vm_map_pmap(map), offset, *page_list,
VM_PROT_READ, TRUE);
page_list++;
}
if (offset == (myaddr + mysize))
break;
/*
* Onward to the next page_list. The extend_cont
* leaves the current page list's pages alone;
* they'll be cleaned up at discard. Reset this
* copy's continuation to discard the next one.
*/
vm_map_copy_invoke_extend_cont(copy, &new_copy, &ret);
if (ret != KERN_SUCCESS) {
kmem_io_map_deallocate(map, myaddr, mysize);
return(ret);
}
copy->cpy_cont = vm_map_copy_discard_cont;
copy->cpy_cont_args = (char *) new_copy;
copy = new_copy;
page_list = ©->cpy_page_list[0];
}
return(ret);
}
/*
* kmem_io_map_deallocate:
*
* Get rid of the mapping established by kmem_io_map_copyout.
* Assumes that addr and size have been rounded to page boundaries.
* (e.g., the alloc_addr and alloc_size returned by kmem_io_map_copyout)
*/
void
kmem_io_map_deallocate(
vm_map_t map,
vm_offset_t addr,
vm_size_t size)
{
/*
* Remove the mappings. The pmap_remove is needed.
*/
pmap_remove(vm_map_pmap(map), addr, addr + size);
vm_map_remove(map, addr, addr + size);
}
/*
* Routine: copyinmap
* Purpose:
* Like copyin, except that fromaddr is an address
* in the specified VM map. This implementation
* is incomplete; it handles the current user map
* and the kernel map/submaps.
*/
int copyinmap(
vm_map_t map,
char *fromaddr,
char *toaddr,
int length)
{
if (vm_map_pmap(map) == kernel_pmap) {
/* assume a correct copy */
memcpy(toaddr, fromaddr, length);
return 0;
}
if (current_map() == map)
return copyin( fromaddr, toaddr, length);
return 1;
}
/*
* Routine: copyoutmap
* Purpose:
* Like copyout, except that toaddr is an address
* in the specified VM map. This implementation
* is incomplete; it handles the current user map
* and the kernel map/submaps.
*/
int copyoutmap(
vm_map_t map,
char *fromaddr,
char *toaddr,
int length)
{
if (vm_map_pmap(map) == kernel_pmap) {
/* assume a correct copy */
memcpy(toaddr, fromaddr, length);
return 0;
}
if (current_map() == map)
return copyout(fromaddr, toaddr, length);
return 1;
}
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