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freebsd/sys/vm/vm_object.h
Matthew Dillon 8b03c8ed5e This is a cleanup patch to Peter's new OBJT_PHYS VM object type
and sysv shared memory support for it.  It implements a new
    PG_UNMANAGED flag that has slightly different characteristics
    from PG_FICTICIOUS.

    A new sysctl, kern.ipc.shm_use_phys has been added to enable the
    use of physically-backed sysv shared memory rather then swap-backed.
    Physically backed shm segments are not tracked with PV entries,
    allowing programs which use a large shm segment as a rendezvous
    point to operate without eating an insane amount of KVM in the
    PV entry management.  Read: Oracle.

    Peter's OBJT_PHYS object will also allow us to eventually implement
    page-table sharing and/or 4MB physical page support for such segments.
    We're half way there.
2000-05-29 22:40:54 +00:00

270 lines
8.5 KiB
C

/*
* 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 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.
*
* from: @(#)vm_object.h 8.3 (Berkeley) 1/12/94
*
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Authors: Avadis Tevanian, Jr., Michael Wayne Young
*
* 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.
*
* $FreeBSD$
*/
/*
* Virtual memory object module definitions.
*/
#ifndef _VM_OBJECT_
#define _VM_OBJECT_
#include <sys/queue.h>
#include <machine/atomic.h>
enum obj_type { OBJT_DEFAULT, OBJT_SWAP, OBJT_VNODE, OBJT_DEVICE, OBJT_PHYS,
OBJT_DEAD };
typedef u_char objtype_t;
/*
* Types defined:
*
* vm_object_t Virtual memory object.
*
*/
struct vm_object {
TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
TAILQ_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
TAILQ_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
TAILQ_HEAD(, vm_page) memq; /* list of resident pages */
int generation; /* generation ID */
vm_size_t size; /* Object size */
int ref_count; /* How many refs?? */
int shadow_count; /* how many objects that this is a shadow for */
int hash_rand; /* vm hash table randomizer */
objtype_t type; /* type of pager */
u_short flags; /* see below */
u_short pg_color; /* color of first page in obj */
u_short paging_in_progress; /* Paging (in or out) so don't collapse or destroy */
int resident_page_count; /* number of resident pages */
struct vm_object *backing_object; /* object that I'm a shadow of */
vm_ooffset_t backing_object_offset;/* Offset in backing object */
TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
void *handle;
union {
/*
* VNode pager
*
* vnp_size - current size of file
*/
struct {
off_t vnp_size;
} vnp;
/*
* Device pager
*
* devp_pglist - list of allocated pages
*/
struct {
TAILQ_HEAD(, vm_page) devp_pglist;
} devp;
#if 0
/*
* Physmem pager
*
* physp_pglist - list of allocated pages
*/
struct {
TAILQ_HEAD(, vm_page) physp_pglist;
} physp;
#endif
/*
* Swap pager
*
* swp_bcount - number of swap 'swblock' metablocks, each
* contains up to 16 swapblk assignments.
* see vm/swap_pager.h
*/
struct {
int swp_bcount;
} swp;
} un_pager;
};
/*
* Flags
*/
#define OBJ_ACTIVE 0x0004 /* active objects */
#define OBJ_DEAD 0x0008 /* dead objects (during rundown) */
#define OBJ_NOSPLIT 0x0010 /* dont split this object */
#define OBJ_PIPWNT 0x0040 /* paging in progress wanted */
#define OBJ_WRITEABLE 0x0080 /* object has been made writable */
#define OBJ_MIGHTBEDIRTY 0x0100 /* object might be dirty */
#define OBJ_CLEANING 0x0200
#define OBJ_OPT 0x1000 /* I/O optimization */
#define OBJ_ONEMAPPING 0x2000 /* One USE (a single, non-forked) mapping flag */
#define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
#define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
#ifdef _KERNEL
#define OBJPC_SYNC 0x1 /* sync I/O */
#define OBJPC_INVAL 0x2 /* invalidate */
#define OBJPC_NOSYNC 0x4 /* skip if PG_NOSYNC */
TAILQ_HEAD(object_q, vm_object);
extern struct object_q vm_object_list; /* list of allocated objects */
/* lock for object list and count */
extern vm_object_t kernel_object; /* the single kernel object */
extern vm_object_t kmem_object;
#endif /* _KERNEL */
#ifdef _KERNEL
static __inline void
vm_object_set_flag(vm_object_t object, u_int bits)
{
atomic_set_short(&object->flags, bits);
}
static __inline void
vm_object_clear_flag(vm_object_t object, u_int bits)
{
atomic_clear_short(&object->flags, bits);
}
static __inline void
vm_object_pip_add(vm_object_t object, int i)
{
atomic_add_short(&object->paging_in_progress, i);
}
static __inline void
vm_object_pip_subtract(vm_object_t object, int i)
{
atomic_subtract_short(&object->paging_in_progress, i);
}
static __inline void
vm_object_pip_wakeup(vm_object_t object)
{
atomic_subtract_short(&object->paging_in_progress, 1);
if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
vm_object_clear_flag(object, OBJ_PIPWNT);
wakeup(object);
}
}
static __inline void
vm_object_pip_wakeupn(vm_object_t object, int i)
{
if (i)
atomic_subtract_short(&object->paging_in_progress, i);
if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
vm_object_clear_flag(object, OBJ_PIPWNT);
wakeup(object);
}
}
static __inline void
vm_object_pip_sleep(vm_object_t object, char *waitid)
{
if (object->paging_in_progress) {
int s = splvm();
if (object->paging_in_progress) {
vm_object_set_flag(object, OBJ_PIPWNT);
tsleep(object, PVM, waitid, 0);
}
splx(s);
}
}
static __inline void
vm_object_pip_wait(vm_object_t object, char *waitid)
{
while (object->paging_in_progress)
vm_object_pip_sleep(object, waitid);
}
vm_object_t vm_object_allocate __P((objtype_t, vm_size_t));
void _vm_object_allocate __P((objtype_t, vm_size_t, vm_object_t));
boolean_t vm_object_coalesce __P((vm_object_t, vm_pindex_t, vm_size_t, vm_size_t));
void vm_object_collapse __P((vm_object_t));
void vm_object_deallocate __P((vm_object_t));
void vm_object_terminate __P((vm_object_t));
void vm_object_vndeallocate __P((vm_object_t));
void vm_object_init __P((void));
void vm_object_page_clean __P((vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t));
void vm_object_page_remove __P((vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t));
void vm_object_pmap_copy __P((vm_object_t, vm_pindex_t, vm_pindex_t));
void vm_object_pmap_copy_1 __P((vm_object_t, vm_pindex_t, vm_pindex_t));
void vm_object_pmap_remove __P((vm_object_t, vm_pindex_t, vm_pindex_t));
void vm_object_reference __P((vm_object_t));
void vm_object_shadow __P((vm_object_t *, vm_ooffset_t *, vm_size_t));
void vm_object_madvise __P((vm_object_t, vm_pindex_t, int, int));
void vm_object_init2 __P((void));
#endif /* _KERNEL */
#endif /* _VM_OBJECT_ */