/*- * 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; /* * 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 #ifdef MALLOC_DECLARE MALLOC_DECLARE(M_VMPGDATA); #endif 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_LOCK_ASSERT(object, MA_OWNED); 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_LOCK_ASSERT(object, MA_OWNED); (*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_LOCK_ASSERT(object, MA_OWNED); 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_LOCK_ASSERT(m->object, MA_OWNED); if (pagertab[m->object->type]->pgo_pageunswapped) (*pagertab[m->object->type]->pgo_pageunswapped)(m); } #endif /* _KERNEL */ #endif /* _VM_PAGER_ */