mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-24 11:29:10 +00:00
89f6b8632c
future further optimizations where the vm_object lock will be held in read mode most of the time the page cache resident pool of pages are accessed for reading purposes. The change is mostly mechanical but few notes are reported: * The KPI changes as follow: - VM_OBJECT_LOCK() -> VM_OBJECT_WLOCK() - VM_OBJECT_TRYLOCK() -> VM_OBJECT_TRYWLOCK() - VM_OBJECT_UNLOCK() -> VM_OBJECT_WUNLOCK() - VM_OBJECT_LOCK_ASSERT(MA_OWNED) -> VM_OBJECT_ASSERT_WLOCKED() (in order to avoid visibility of implementation details) - The read-mode operations are added: VM_OBJECT_RLOCK(), VM_OBJECT_TRYRLOCK(), VM_OBJECT_RUNLOCK(), VM_OBJECT_ASSERT_RLOCKED(), VM_OBJECT_ASSERT_LOCKED() * The vm/vm_pager.h namespace pollution avoidance (forcing requiring sys/mutex.h in consumers directly to cater its inlining functions using VM_OBJECT_LOCK()) imposes that all the vm/vm_pager.h consumers now must include also sys/rwlock.h. * zfs requires a quite convoluted fix to include FreeBSD rwlocks into the compat layer because the name clash between FreeBSD and solaris versions must be avoided. At this purpose zfs redefines the vm_object locking functions directly, isolating the FreeBSD components in specific compat stubs. The KPI results heavilly broken by this commit. Thirdy part ports must be updated accordingly (I can think off-hand of VirtualBox, for example). Sponsored by: EMC / Isilon storage division Reviewed by: jeff Reviewed by: pjd (ZFS specific review) Discussed with: alc Tested by: pho
212 lines
6.7 KiB
C
212 lines
6.7 KiB
C
/*-
|
|
* 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.
|
|
*
|
|
* @(#)vm_pager.h 8.4 (Berkeley) 1/12/94
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
/*
|
|
* Pager routine interface definition.
|
|
*/
|
|
|
|
#ifndef _VM_PAGER_
|
|
#define _VM_PAGER_
|
|
|
|
#include <sys/queue.h>
|
|
|
|
TAILQ_HEAD(pagerlst, vm_object);
|
|
|
|
typedef void pgo_init_t(void);
|
|
typedef vm_object_t pgo_alloc_t(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t,
|
|
struct ucred *);
|
|
typedef void pgo_dealloc_t(vm_object_t);
|
|
typedef int pgo_getpages_t(vm_object_t, vm_page_t *, int, int);
|
|
typedef void pgo_putpages_t(vm_object_t, vm_page_t *, int, int, int *);
|
|
typedef boolean_t pgo_haspage_t(vm_object_t, vm_pindex_t, int *, int *);
|
|
typedef void pgo_pageunswapped_t(vm_page_t);
|
|
|
|
struct pagerops {
|
|
pgo_init_t *pgo_init; /* Initialize pager. */
|
|
pgo_alloc_t *pgo_alloc; /* Allocate pager. */
|
|
pgo_dealloc_t *pgo_dealloc; /* Disassociate. */
|
|
pgo_getpages_t *pgo_getpages; /* Get (read) page. */
|
|
pgo_putpages_t *pgo_putpages; /* Put (write) page. */
|
|
pgo_haspage_t *pgo_haspage; /* Does pager have page? */
|
|
pgo_pageunswapped_t *pgo_pageunswapped;
|
|
};
|
|
|
|
extern struct pagerops defaultpagerops;
|
|
extern struct pagerops swappagerops;
|
|
extern struct pagerops vnodepagerops;
|
|
extern struct pagerops devicepagerops;
|
|
extern struct pagerops physpagerops;
|
|
extern struct pagerops sgpagerops;
|
|
extern struct pagerops mgtdevicepagerops;
|
|
|
|
/*
|
|
* get/put return values
|
|
* OK operation was successful
|
|
* BAD specified data was out of the accepted range
|
|
* FAIL specified data was in range, but doesn't exist
|
|
* PEND operations was initiated but not completed
|
|
* ERROR error while accessing data that is in range and exists
|
|
* AGAIN temporary resource shortage prevented operation from happening
|
|
*/
|
|
#define VM_PAGER_OK 0
|
|
#define VM_PAGER_BAD 1
|
|
#define VM_PAGER_FAIL 2
|
|
#define VM_PAGER_PEND 3
|
|
#define VM_PAGER_ERROR 4
|
|
#define VM_PAGER_AGAIN 5
|
|
|
|
#define VM_PAGER_PUT_SYNC 0x0001
|
|
#define VM_PAGER_PUT_INVAL 0x0002
|
|
#define VM_PAGER_CLUSTER_OK 0x0008
|
|
|
|
#ifdef _KERNEL
|
|
|
|
extern vm_map_t pager_map;
|
|
extern struct pagerops *pagertab[];
|
|
extern struct mtx pbuf_mtx;
|
|
|
|
vm_object_t vm_pager_allocate(objtype_t, void *, vm_ooffset_t, vm_prot_t,
|
|
vm_ooffset_t, struct ucred *);
|
|
void vm_pager_bufferinit(void);
|
|
void vm_pager_deallocate(vm_object_t);
|
|
static __inline int vm_pager_get_pages(vm_object_t, vm_page_t *, int, int);
|
|
static __inline boolean_t vm_pager_has_page(vm_object_t, vm_pindex_t, int *, int *);
|
|
void vm_pager_init(void);
|
|
vm_object_t vm_pager_object_lookup(struct pagerlst *, void *);
|
|
|
|
/*
|
|
* vm_page_get_pages:
|
|
*
|
|
* Retrieve pages from the VM system in order to map them into an object
|
|
* ( or into VM space somewhere ). If the pagein was successful, we
|
|
* must fully validate it.
|
|
*/
|
|
static __inline int
|
|
vm_pager_get_pages(
|
|
vm_object_t object,
|
|
vm_page_t *m,
|
|
int count,
|
|
int reqpage
|
|
) {
|
|
int r;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
r = (*pagertab[object->type]->pgo_getpages)(object, m, count, reqpage);
|
|
if (r == VM_PAGER_OK && m[reqpage]->valid != VM_PAGE_BITS_ALL) {
|
|
vm_page_zero_invalid(m[reqpage], TRUE);
|
|
}
|
|
return (r);
|
|
}
|
|
|
|
static __inline void
|
|
vm_pager_put_pages(
|
|
vm_object_t object,
|
|
vm_page_t *m,
|
|
int count,
|
|
int flags,
|
|
int *rtvals
|
|
) {
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
(*pagertab[object->type]->pgo_putpages)
|
|
(object, m, count, flags, rtvals);
|
|
}
|
|
|
|
/*
|
|
* vm_pager_haspage
|
|
*
|
|
* Check to see if an object's pager has the requested page. The
|
|
* object's pager will also set before and after to give the caller
|
|
* some idea of the number of pages before and after the requested
|
|
* page can be I/O'd efficiently.
|
|
*
|
|
* The object must be locked.
|
|
*/
|
|
static __inline boolean_t
|
|
vm_pager_has_page(
|
|
vm_object_t object,
|
|
vm_pindex_t offset,
|
|
int *before,
|
|
int *after
|
|
) {
|
|
boolean_t ret;
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(object);
|
|
ret = (*pagertab[object->type]->pgo_haspage)
|
|
(object, offset, before, after);
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* vm_pager_page_unswapped
|
|
*
|
|
* Destroy swap associated with the page.
|
|
*
|
|
* The object containing the page must be locked.
|
|
* This function may not block.
|
|
*
|
|
* XXX: A much better name would be "vm_pager_page_dirtied()"
|
|
* XXX: It is not obvious if this could be profitably used by any
|
|
* XXX: pagers besides the swap_pager or if it should even be a
|
|
* XXX: generic pager_op in the first place.
|
|
*/
|
|
static __inline void
|
|
vm_pager_page_unswapped(vm_page_t m)
|
|
{
|
|
|
|
VM_OBJECT_ASSERT_WLOCKED(m->object);
|
|
if (pagertab[m->object->type]->pgo_pageunswapped)
|
|
(*pagertab[m->object->type]->pgo_pageunswapped)(m);
|
|
}
|
|
|
|
struct cdev_pager_ops {
|
|
int (*cdev_pg_fault)(vm_object_t vm_obj, vm_ooffset_t offset,
|
|
int prot, vm_page_t *mres);
|
|
int (*cdev_pg_ctor)(void *handle, vm_ooffset_t size, vm_prot_t prot,
|
|
vm_ooffset_t foff, struct ucred *cred, u_short *color);
|
|
void (*cdev_pg_dtor)(void *handle);
|
|
};
|
|
|
|
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 cdev_pager_lookup(void *handle);
|
|
void cdev_pager_free_page(vm_object_t object, vm_page_t m);
|
|
|
|
#endif /* _KERNEL */
|
|
#endif /* _VM_PAGER_ */
|