NetBSD/sys/uvm/uvm_km.c

795 lines
22 KiB
C

/* $NetBSD: uvm_km.c,v 1.106 2010/05/14 05:02:06 cegger Exp $ */
/*
* Copyright (c) 1997 Charles D. Cranor and Washington University.
* 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 Mach Operating System project at Carnegie-Mellon University.
*
* 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 Charles D. Cranor,
* Washington University, 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.
*
* @(#)vm_kern.c 8.3 (Berkeley) 1/12/94
* from: Id: uvm_km.c,v 1.1.2.14 1998/02/06 05:19:27 chs Exp
*
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* 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 ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS 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 the
* rights to redistribute these changes.
*/
/*
* uvm_km.c: handle kernel memory allocation and management
*/
/*
* overview of kernel memory management:
*
* the kernel virtual address space is mapped by "kernel_map." kernel_map
* starts at VM_MIN_KERNEL_ADDRESS and goes to VM_MAX_KERNEL_ADDRESS.
* note that VM_MIN_KERNEL_ADDRESS is equal to vm_map_min(kernel_map).
*
* the kernel_map has several "submaps." submaps can only appear in
* the kernel_map (user processes can't use them). submaps "take over"
* the management of a sub-range of the kernel's address space. submaps
* are typically allocated at boot time and are never released. kernel
* virtual address space that is mapped by a submap is locked by the
* submap's lock -- not the kernel_map's lock.
*
* thus, the useful feature of submaps is that they allow us to break
* up the locking and protection of the kernel address space into smaller
* chunks.
*
* the vm system has several standard kernel submaps, including:
* kmem_map => contains only wired kernel memory for the kernel
* malloc.
* pager_map => used to map "buf" structures into kernel space
* exec_map => used during exec to handle exec args
* etc...
*
* the kernel allocates its private memory out of special uvm_objects whose
* reference count is set to UVM_OBJ_KERN (thus indicating that the objects
* are "special" and never die). all kernel objects should be thought of
* as large, fixed-sized, sparsely populated uvm_objects. each kernel
* object is equal to the size of kernel virtual address space (i.e. the
* value "VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS").
*
* note that just because a kernel object spans the entire kernel virtual
* address space doesn't mean that it has to be mapped into the entire space.
* large chunks of a kernel object's space go unused either because
* that area of kernel VM is unmapped, or there is some other type of
* object mapped into that range (e.g. a vnode). for submap's kernel
* objects, the only part of the object that can ever be populated is the
* offsets that are managed by the submap.
*
* note that the "offset" in a kernel object is always the kernel virtual
* address minus the VM_MIN_KERNEL_ADDRESS (aka vm_map_min(kernel_map)).
* example:
* suppose VM_MIN_KERNEL_ADDRESS is 0xf8000000 and the kernel does a
* uvm_km_alloc(kernel_map, PAGE_SIZE) [allocate 1 wired down page in the
* kernel map]. if uvm_km_alloc returns virtual address 0xf8235000,
* then that means that the page at offset 0x235000 in kernel_object is
* mapped at 0xf8235000.
*
* kernel object have one other special property: when the kernel virtual
* memory mapping them is unmapped, the backing memory in the object is
* freed right away. this is done with the uvm_km_pgremove() function.
* this has to be done because there is no backing store for kernel pages
* and no need to save them after they are no longer referenced.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uvm_km.c,v 1.106 2010/05/14 05:02:06 cegger Exp $");
#include "opt_uvmhist.h"
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/pool.h>
#include <uvm/uvm.h>
/*
* global data structures
*/
struct vm_map *kernel_map = NULL;
/*
* local data structues
*/
static struct vm_map_kernel kernel_map_store;
static struct vm_map_entry kernel_first_mapent_store;
#if !defined(PMAP_MAP_POOLPAGE)
/*
* kva cache
*
* XXX maybe it's better to do this at the uvm_map layer.
*/
#define KM_VACACHE_SIZE (32 * PAGE_SIZE) /* XXX tune */
static void *km_vacache_alloc(struct pool *, int);
static void km_vacache_free(struct pool *, void *);
static void km_vacache_init(struct vm_map *, const char *, size_t);
/* XXX */
#define KM_VACACHE_POOL_TO_MAP(pp) \
((struct vm_map *)((char *)(pp) - \
offsetof(struct vm_map_kernel, vmk_vacache)))
static void *
km_vacache_alloc(struct pool *pp, int flags)
{
vaddr_t va;
size_t size;
struct vm_map *map;
size = pp->pr_alloc->pa_pagesz;
map = KM_VACACHE_POOL_TO_MAP(pp);
va = vm_map_min(map); /* hint */
if (uvm_map(map, &va, size, NULL, UVM_UNKNOWN_OFFSET, size,
UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE,
UVM_ADV_RANDOM, UVM_FLAG_QUANTUM |
((flags & PR_WAITOK) ? UVM_FLAG_WAITVA :
UVM_FLAG_TRYLOCK | UVM_FLAG_NOWAIT))))
return NULL;
return (void *)va;
}
static void
km_vacache_free(struct pool *pp, void *v)
{
vaddr_t va = (vaddr_t)v;
size_t size = pp->pr_alloc->pa_pagesz;
struct vm_map *map;
map = KM_VACACHE_POOL_TO_MAP(pp);
uvm_unmap1(map, va, va + size, UVM_FLAG_QUANTUM|UVM_FLAG_VAONLY);
}
/*
* km_vacache_init: initialize kva cache.
*/
static void
km_vacache_init(struct vm_map *map, const char *name, size_t size)
{
struct vm_map_kernel *vmk;
struct pool *pp;
struct pool_allocator *pa;
int ipl;
KASSERT(VM_MAP_IS_KERNEL(map));
KASSERT(size < (vm_map_max(map) - vm_map_min(map)) / 2); /* sanity */
vmk = vm_map_to_kernel(map);
pp = &vmk->vmk_vacache;
pa = &vmk->vmk_vacache_allocator;
memset(pa, 0, sizeof(*pa));
pa->pa_alloc = km_vacache_alloc;
pa->pa_free = km_vacache_free;
pa->pa_pagesz = (unsigned int)size;
pa->pa_backingmap = map;
pa->pa_backingmapptr = NULL;
if ((map->flags & VM_MAP_INTRSAFE) != 0)
ipl = IPL_VM;
else
ipl = IPL_NONE;
pool_init(pp, PAGE_SIZE, 0, 0, PR_NOTOUCH | PR_RECURSIVE, name, pa,
ipl);
}
void
uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size)
{
map->flags |= VM_MAP_VACACHE;
if (size == 0)
size = KM_VACACHE_SIZE;
km_vacache_init(map, name, size);
}
#else /* !defined(PMAP_MAP_POOLPAGE) */
void
uvm_km_vacache_init(struct vm_map *map, const char *name, size_t size)
{
/* nothing */
}
#endif /* !defined(PMAP_MAP_POOLPAGE) */
void
uvm_km_va_drain(struct vm_map *map, uvm_flag_t flags)
{
struct vm_map_kernel *vmk = vm_map_to_kernel(map);
callback_run_roundrobin(&vmk->vmk_reclaim_callback, NULL);
}
/*
* uvm_km_init: init kernel maps and objects to reflect reality (i.e.
* KVM already allocated for text, data, bss, and static data structures).
*
* => KVM is defined by VM_MIN_KERNEL_ADDRESS/VM_MAX_KERNEL_ADDRESS.
* we assume that [vmin -> start] has already been allocated and that
* "end" is the end.
*/
void
uvm_km_init(vaddr_t start, vaddr_t end)
{
vaddr_t base = VM_MIN_KERNEL_ADDRESS;
/*
* next, init kernel memory objects.
*/
/* kernel_object: for pageable anonymous kernel memory */
uao_init();
uvm_kernel_object = uao_create(VM_MAX_KERNEL_ADDRESS -
VM_MIN_KERNEL_ADDRESS, UAO_FLAG_KERNOBJ);
/*
* init the map and reserve any space that might already
* have been allocated kernel space before installing.
*/
uvm_map_setup_kernel(&kernel_map_store, base, end, VM_MAP_PAGEABLE);
kernel_map_store.vmk_map.pmap = pmap_kernel();
if (start != base) {
int error;
struct uvm_map_args args;
error = uvm_map_prepare(&kernel_map_store.vmk_map,
base, start - base,
NULL, UVM_UNKNOWN_OFFSET, 0,
UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE,
UVM_ADV_RANDOM, UVM_FLAG_FIXED), &args);
if (!error) {
kernel_first_mapent_store.flags =
UVM_MAP_KERNEL | UVM_MAP_FIRST;
error = uvm_map_enter(&kernel_map_store.vmk_map, &args,
&kernel_first_mapent_store);
}
if (error)
panic(
"uvm_km_init: could not reserve space for kernel");
}
/*
* install!
*/
kernel_map = &kernel_map_store.vmk_map;
uvm_km_vacache_init(kernel_map, "kvakernel", 0);
}
/*
* uvm_km_suballoc: allocate a submap in the kernel map. once a submap
* is allocated all references to that area of VM must go through it. this
* allows the locking of VAs in kernel_map to be broken up into regions.
*
* => if `fixed' is true, *vmin specifies where the region described
* by the submap must start
* => if submap is non NULL we use that as the submap, otherwise we
* alloc a new map
*/
struct vm_map *
uvm_km_suballoc(struct vm_map *map, vaddr_t *vmin /* IN/OUT */,
vaddr_t *vmax /* OUT */, vsize_t size, int flags, bool fixed,
struct vm_map_kernel *submap)
{
int mapflags = UVM_FLAG_NOMERGE | (fixed ? UVM_FLAG_FIXED : 0);
KASSERT(vm_map_pmap(map) == pmap_kernel());
size = round_page(size); /* round up to pagesize */
size += uvm_mapent_overhead(size, flags);
/*
* first allocate a blank spot in the parent map
*/
if (uvm_map(map, vmin, size, NULL, UVM_UNKNOWN_OFFSET, 0,
UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE,
UVM_ADV_RANDOM, mapflags)) != 0) {
panic("uvm_km_suballoc: unable to allocate space in parent map");
}
/*
* set VM bounds (vmin is filled in by uvm_map)
*/
*vmax = *vmin + size;
/*
* add references to pmap and create or init the submap
*/
pmap_reference(vm_map_pmap(map));
if (submap == NULL) {
submap = malloc(sizeof(*submap), M_VMMAP, M_WAITOK);
if (submap == NULL)
panic("uvm_km_suballoc: unable to create submap");
}
uvm_map_setup_kernel(submap, *vmin, *vmax, flags);
submap->vmk_map.pmap = vm_map_pmap(map);
/*
* now let uvm_map_submap plug in it...
*/
if (uvm_map_submap(map, *vmin, *vmax, &submap->vmk_map) != 0)
panic("uvm_km_suballoc: submap allocation failed");
return(&submap->vmk_map);
}
/*
* uvm_km_pgremove: remove pages from a kernel uvm_object.
*
* => when you unmap a part of anonymous kernel memory you want to toss
* the pages right away. (this gets called from uvm_unmap_...).
*/
void
uvm_km_pgremove(vaddr_t startva, vaddr_t endva)
{
struct uvm_object * const uobj = uvm_kernel_object;
const voff_t start = startva - vm_map_min(kernel_map);
const voff_t end = endva - vm_map_min(kernel_map);
struct vm_page *pg;
voff_t curoff, nextoff;
int swpgonlydelta = 0;
UVMHIST_FUNC("uvm_km_pgremove"); UVMHIST_CALLED(maphist);
KASSERT(VM_MIN_KERNEL_ADDRESS <= startva);
KASSERT(startva < endva);
KASSERT(endva <= VM_MAX_KERNEL_ADDRESS);
mutex_enter(&uobj->vmobjlock);
for (curoff = start; curoff < end; curoff = nextoff) {
nextoff = curoff + PAGE_SIZE;
pg = uvm_pagelookup(uobj, curoff);
if (pg != NULL && pg->flags & PG_BUSY) {
pg->flags |= PG_WANTED;
UVM_UNLOCK_AND_WAIT(pg, &uobj->vmobjlock, 0,
"km_pgrm", 0);
mutex_enter(&uobj->vmobjlock);
nextoff = curoff;
continue;
}
/*
* free the swap slot, then the page.
*/
if (pg == NULL &&
uao_find_swslot(uobj, curoff >> PAGE_SHIFT) > 0) {
swpgonlydelta++;
}
uao_dropswap(uobj, curoff >> PAGE_SHIFT);
if (pg != NULL) {
mutex_enter(&uvm_pageqlock);
uvm_pagefree(pg);
mutex_exit(&uvm_pageqlock);
}
}
mutex_exit(&uobj->vmobjlock);
if (swpgonlydelta > 0) {
mutex_enter(&uvm_swap_data_lock);
KASSERT(uvmexp.swpgonly >= swpgonlydelta);
uvmexp.swpgonly -= swpgonlydelta;
mutex_exit(&uvm_swap_data_lock);
}
}
/*
* uvm_km_pgremove_intrsafe: like uvm_km_pgremove(), but for non object backed
* regions.
*
* => when you unmap a part of anonymous kernel memory you want to toss
* the pages right away. (this is called from uvm_unmap_...).
* => none of the pages will ever be busy, and none of them will ever
* be on the active or inactive queues (because they have no object).
*/
void
uvm_km_pgremove_intrsafe(struct vm_map *map, vaddr_t start, vaddr_t end)
{
struct vm_page *pg;
paddr_t pa;
UVMHIST_FUNC("uvm_km_pgremove_intrsafe"); UVMHIST_CALLED(maphist);
KASSERT(VM_MAP_IS_KERNEL(map));
KASSERT(vm_map_min(map) <= start);
KASSERT(start < end);
KASSERT(end <= vm_map_max(map));
for (; start < end; start += PAGE_SIZE) {
if (!pmap_extract(pmap_kernel(), start, &pa)) {
continue;
}
pg = PHYS_TO_VM_PAGE(pa);
KASSERT(pg);
KASSERT(pg->uobject == NULL && pg->uanon == NULL);
uvm_pagefree(pg);
}
}
#if defined(DEBUG)
void
uvm_km_check_empty(struct vm_map *map, vaddr_t start, vaddr_t end)
{
struct vm_page *pg;
vaddr_t va;
paddr_t pa;
KDASSERT(VM_MAP_IS_KERNEL(map));
KDASSERT(vm_map_min(map) <= start);
KDASSERT(start < end);
KDASSERT(end <= vm_map_max(map));
for (va = start; va < end; va += PAGE_SIZE) {
if (pmap_extract(pmap_kernel(), va, &pa)) {
panic("uvm_km_check_empty: va %p has pa 0x%llx",
(void *)va, (long long)pa);
}
if ((map->flags & VM_MAP_INTRSAFE) == 0) {
mutex_enter(&uvm_kernel_object->vmobjlock);
pg = uvm_pagelookup(uvm_kernel_object,
va - vm_map_min(kernel_map));
mutex_exit(&uvm_kernel_object->vmobjlock);
if (pg) {
panic("uvm_km_check_empty: "
"has page hashed at %p", (const void *)va);
}
}
}
}
#endif /* defined(DEBUG) */
/*
* uvm_km_alloc: allocate an area of kernel memory.
*
* => NOTE: we can return 0 even if we can wait if there is not enough
* free VM space in the map... caller should be prepared to handle
* this case.
* => we return KVA of memory allocated
*/
vaddr_t
uvm_km_alloc(struct vm_map *map, vsize_t size, vsize_t align, uvm_flag_t flags)
{
vaddr_t kva, loopva;
vaddr_t offset;
vsize_t loopsize;
struct vm_page *pg;
struct uvm_object *obj;
int pgaflags;
vm_prot_t prot;
UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist);
KASSERT(vm_map_pmap(map) == pmap_kernel());
KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED ||
(flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE ||
(flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY);
/*
* setup for call
*/
kva = vm_map_min(map); /* hint */
size = round_page(size);
obj = (flags & UVM_KMF_PAGEABLE) ? uvm_kernel_object : NULL;
UVMHIST_LOG(maphist," (map=0x%x, obj=0x%x, size=0x%x, flags=%d)",
map, obj, size, flags);
/*
* allocate some virtual space
*/
if (__predict_false(uvm_map(map, &kva, size, obj, UVM_UNKNOWN_OFFSET,
align, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_NONE,
UVM_ADV_RANDOM,
(flags & (UVM_KMF_TRYLOCK | UVM_KMF_NOWAIT | UVM_KMF_WAITVA))
| UVM_FLAG_QUANTUM)) != 0)) {
UVMHIST_LOG(maphist, "<- done (no VM)",0,0,0,0);
return(0);
}
/*
* if all we wanted was VA, return now
*/
if (flags & (UVM_KMF_VAONLY | UVM_KMF_PAGEABLE)) {
UVMHIST_LOG(maphist,"<- done valloc (kva=0x%x)", kva,0,0,0);
return(kva);
}
/*
* recover object offset from virtual address
*/
offset = kva - vm_map_min(kernel_map);
UVMHIST_LOG(maphist, " kva=0x%x, offset=0x%x", kva, offset,0,0);
/*
* now allocate and map in the memory... note that we are the only ones
* whom should ever get a handle on this area of VM.
*/
loopva = kva;
loopsize = size;
pgaflags = 0;
if (flags & UVM_KMF_NOWAIT)
pgaflags |= UVM_PGA_USERESERVE;
if (flags & UVM_KMF_ZERO)
pgaflags |= UVM_PGA_ZERO;
prot = VM_PROT_READ | VM_PROT_WRITE;
if (flags & UVM_KMF_EXEC)
prot |= VM_PROT_EXECUTE;
while (loopsize) {
KASSERT(!pmap_extract(pmap_kernel(), loopva, NULL));
pg = uvm_pagealloc(NULL, offset, NULL, pgaflags);
/*
* out of memory?
*/
if (__predict_false(pg == NULL)) {
if ((flags & UVM_KMF_NOWAIT) ||
((flags & UVM_KMF_CANFAIL) && !uvm_reclaimable())) {
/* free everything! */
uvm_km_free(map, kva, size,
flags & UVM_KMF_TYPEMASK);
return (0);
} else {
uvm_wait("km_getwait2"); /* sleep here */
continue;
}
}
pg->flags &= ~PG_BUSY; /* new page */
UVM_PAGE_OWN(pg, NULL);
/*
* map it in
*/
pmap_kenter_pa(loopva, VM_PAGE_TO_PHYS(pg),
prot, PMAP_KMPAGE);
loopva += PAGE_SIZE;
offset += PAGE_SIZE;
loopsize -= PAGE_SIZE;
}
pmap_update(pmap_kernel());
UVMHIST_LOG(maphist,"<- done (kva=0x%x)", kva,0,0,0);
return(kva);
}
/*
* uvm_km_free: free an area of kernel memory
*/
void
uvm_km_free(struct vm_map *map, vaddr_t addr, vsize_t size, uvm_flag_t flags)
{
KASSERT((flags & UVM_KMF_TYPEMASK) == UVM_KMF_WIRED ||
(flags & UVM_KMF_TYPEMASK) == UVM_KMF_PAGEABLE ||
(flags & UVM_KMF_TYPEMASK) == UVM_KMF_VAONLY);
KASSERT((addr & PAGE_MASK) == 0);
KASSERT(vm_map_pmap(map) == pmap_kernel());
size = round_page(size);
if (flags & UVM_KMF_PAGEABLE) {
uvm_km_pgremove(addr, addr + size);
pmap_remove(pmap_kernel(), addr, addr + size);
} else if (flags & UVM_KMF_WIRED) {
uvm_km_pgremove_intrsafe(map, addr, addr + size);
pmap_kremove(addr, size);
}
/*
* uvm_unmap_remove calls pmap_update for us.
*/
uvm_unmap1(map, addr, addr + size, UVM_FLAG_QUANTUM|UVM_FLAG_VAONLY);
}
/* Sanity; must specify both or none. */
#if (defined(PMAP_MAP_POOLPAGE) || defined(PMAP_UNMAP_POOLPAGE)) && \
(!defined(PMAP_MAP_POOLPAGE) || !defined(PMAP_UNMAP_POOLPAGE))
#error Must specify MAP and UNMAP together.
#endif
/*
* uvm_km_alloc_poolpage: allocate a page for the pool allocator
*
* => if the pmap specifies an alternate mapping method, we use it.
*/
/* ARGSUSED */
vaddr_t
uvm_km_alloc_poolpage_cache(struct vm_map *map, bool waitok)
{
#if defined(PMAP_MAP_POOLPAGE)
return uvm_km_alloc_poolpage(map, waitok);
#else
struct vm_page *pg;
struct pool *pp = &vm_map_to_kernel(map)->vmk_vacache;
vaddr_t va;
if ((map->flags & VM_MAP_VACACHE) == 0)
return uvm_km_alloc_poolpage(map, waitok);
va = (vaddr_t)pool_get(pp, waitok ? PR_WAITOK : PR_NOWAIT);
if (va == 0)
return 0;
KASSERT(!pmap_extract(pmap_kernel(), va, NULL));
again:
pg = uvm_pagealloc(NULL, 0, NULL, waitok ? 0 : UVM_PGA_USERESERVE);
if (__predict_false(pg == NULL)) {
if (waitok) {
uvm_wait("plpg");
goto again;
} else {
pool_put(pp, (void *)va);
return 0;
}
}
pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pg),
VM_PROT_READ|VM_PROT_WRITE, PMAP_KMPAGE);
pmap_update(pmap_kernel());
return va;
#endif /* PMAP_MAP_POOLPAGE */
}
vaddr_t
uvm_km_alloc_poolpage(struct vm_map *map, bool waitok)
{
#if defined(PMAP_MAP_POOLPAGE)
struct vm_page *pg;
vaddr_t va;
again:
pg = uvm_pagealloc(NULL, 0, NULL, waitok ? 0 : UVM_PGA_USERESERVE);
if (__predict_false(pg == NULL)) {
if (waitok) {
uvm_wait("plpg");
goto again;
} else
return (0);
}
va = PMAP_MAP_POOLPAGE(VM_PAGE_TO_PHYS(pg));
if (__predict_false(va == 0))
uvm_pagefree(pg);
return (va);
#else
vaddr_t va;
va = uvm_km_alloc(map, PAGE_SIZE, 0,
(waitok ? 0 : UVM_KMF_NOWAIT | UVM_KMF_TRYLOCK) | UVM_KMF_WIRED);
return (va);
#endif /* PMAP_MAP_POOLPAGE */
}
/*
* uvm_km_free_poolpage: free a previously allocated pool page
*
* => if the pmap specifies an alternate unmapping method, we use it.
*/
/* ARGSUSED */
void
uvm_km_free_poolpage_cache(struct vm_map *map, vaddr_t addr)
{
#if defined(PMAP_UNMAP_POOLPAGE)
uvm_km_free_poolpage(map, addr);
#else
struct pool *pp;
if ((map->flags & VM_MAP_VACACHE) == 0) {
uvm_km_free_poolpage(map, addr);
return;
}
KASSERT(pmap_extract(pmap_kernel(), addr, NULL));
uvm_km_pgremove_intrsafe(map, addr, addr + PAGE_SIZE);
pmap_kremove(addr, PAGE_SIZE);
#if defined(DEBUG)
pmap_update(pmap_kernel());
#endif
KASSERT(!pmap_extract(pmap_kernel(), addr, NULL));
pp = &vm_map_to_kernel(map)->vmk_vacache;
pool_put(pp, (void *)addr);
#endif
}
/* ARGSUSED */
void
uvm_km_free_poolpage(struct vm_map *map, vaddr_t addr)
{
#if defined(PMAP_UNMAP_POOLPAGE)
paddr_t pa;
pa = PMAP_UNMAP_POOLPAGE(addr);
uvm_pagefree(PHYS_TO_VM_PAGE(pa));
#else
uvm_km_free(map, addr, PAGE_SIZE, UVM_KMF_WIRED);
#endif /* PMAP_UNMAP_POOLPAGE */
}