Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Use vm_object_prefer() to find a good range of virtual addresses to

Browse Source 
map a memory object to.
This commit is contained in:
pk 1994-12-10 11:48:12 +00:00
parent d114baba9a
commit 3e4bf211c6
1 changed files with 45 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
sys/vm/vm_mmap.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: vm_mmap.c,v 1.35 1994/12/01 00:23:11 gwr Exp $ */
/* $NetBSD: vm_mmap.c,v 1.36 1994/12/10 11:48:12 pk Exp $ */
/*
* Copyright (c) 1988 University of Utah.
@ -815,8 +815,50 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
vm_offset_t off;
/* locate and allocate the target address space */
rv = vm_map_find(map, NULL, (vm_offset_t)0,
addr, size, fitit);
if (fitit) {
/*
* We cannot call vm_map_find() because
* a proposed address may be vetoed by
* the pmap module.
* So we look for space ourselves, validate
* it and insert it into the map.
*/
vm_map_lock(map);
again:
if (vm_map_findspace(map, *addr, size,
addr) == 1) {
rv = KERN_NO_SPACE;
} else {
vm_object_prefer(object, foff, addr);
rv = vm_map_insert(map, NULL,
(vm_offset_t)0,
*addr, *addr+size);
if (rv == KERN_NO_SPACE)
/*
* Modified address didn't fit
* after all, the gap must
* have been to small.
*/
goto again;
}
vm_map_unlock(map);
} else {
rv = vm_map_find(map, NULL, (vm_offset_t)0,
addr, size, 0);
/*
* Check against PMAP preferred address. If
* there's a mismatch, these pages should not
* be shared with others. <howto?>
*/
if (rv == KERN_SUCCESS) {
vm_offset_t paddr = *addr;
vm_object_prefer(object, foff, &paddr);
if (paddr != *addr)
printf("vm_mmap: pmap botch!\n");
}
}
if (rv != KERN_SUCCESS) {
vm_object_deallocate(object);
goto out;