/* * 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_pager.c 8.6 (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. * * $Id: vm_pager.c,v 1.32 1998/01/24 02:01:46 dyson Exp $ */ /* * Paging space routine stubs. Emulates a matchmaker-like interface * for builtin pagers. */ #include "opt_diagnostic.h" #include #include #include #include #include #include #include #include #include #include #include #include MALLOC_DEFINE(M_VMPGDATA, "VM pgdata", "XXX: VM pager private data"); extern struct pagerops defaultpagerops; extern struct pagerops swappagerops; extern struct pagerops vnodepagerops; extern struct pagerops devicepagerops; static struct pagerops *pagertab[] = { &defaultpagerops, /* OBJT_DEFAULT */ &swappagerops, /* OBJT_SWAP */ &vnodepagerops, /* OBJT_VNODE */ &devicepagerops, /* OBJT_DEVICE */ }; static int npagers = sizeof(pagertab) / sizeof(pagertab[0]); /* * Kernel address space for mapping pages. * Used by pagers where KVAs are needed for IO. * * XXX needs to be large enough to support the number of pending async * cleaning requests (NPENDINGIO == 64) * the maximum swap cluster size * (MAXPHYS == 64k) if you want to get the most efficiency. */ #define PAGER_MAP_SIZE (8 * 1024 * 1024) int pager_map_size = PAGER_MAP_SIZE; vm_map_t pager_map; static int bswneeded; static vm_offset_t swapbkva; /* swap buffers kva */ void vm_pager_init() { struct pagerops **pgops; /* * Initialize known pagers */ for (pgops = pagertab; pgops < &pagertab[npagers]; pgops++) if (pgops && ((*pgops)->pgo_init != NULL)) (*(*pgops)->pgo_init) (); } void vm_pager_bufferinit() { struct buf *bp; int i; bp = swbuf; /* * Now set up swap and physical I/O buffer headers. */ for (i = 0; i < nswbuf; i++, bp++) { TAILQ_INSERT_HEAD(&bswlist, bp, b_freelist); bp->b_rcred = bp->b_wcred = NOCRED; bp->b_vnbufs.le_next = NOLIST; } swapbkva = kmem_alloc_pageable(pager_map, nswbuf * MAXPHYS); if (!swapbkva) panic("Not enough pager_map VM space for physical buffers"); } /* * Allocate an instance of a pager of the given type. * Size, protection and offset parameters are passed in for pagers that * need to perform page-level validation (e.g. the device pager). */ vm_object_t vm_pager_allocate(objtype_t type, void *handle, vm_size_t size, vm_prot_t prot, vm_ooffset_t off) { struct pagerops *ops; ops = pagertab[type]; if (ops) return ((*ops->pgo_alloc) (handle, size, prot, off)); return (NULL); } void vm_pager_deallocate(object) vm_object_t object; { (*pagertab[object->type]->pgo_dealloc) (object); } int vm_pager_get_pages(object, m, count, reqpage) vm_object_t object; vm_page_t *m; int count; int reqpage; { return ((*pagertab[object->type]->pgo_getpages)(object, m, count, reqpage)); } int vm_pager_put_pages(object, m, count, sync, rtvals) vm_object_t object; vm_page_t *m; int count; boolean_t sync; int *rtvals; { return ((*pagertab[object->type]->pgo_putpages)(object, m, count, sync, rtvals)); } boolean_t vm_pager_has_page(object, offset, before, after) vm_object_t object; vm_pindex_t offset; int *before; int *after; { return ((*pagertab[object->type]->pgo_haspage) (object, offset, before, after)); } /* * Called by pageout daemon before going back to sleep. * Gives pagers a chance to clean up any completed async pageing operations. */ void vm_pager_sync() { struct pagerops **pgops; for (pgops = pagertab; pgops < &pagertab[npagers]; pgops++) if (pgops && ((*pgops)->pgo_sync != NULL)) (*(*pgops)->pgo_sync) (); } vm_offset_t vm_pager_map_page(m) vm_page_t m; { vm_offset_t kva; kva = kmem_alloc_wait(pager_map, PAGE_SIZE); pmap_kenter(kva, VM_PAGE_TO_PHYS(m)); return (kva); } void vm_pager_unmap_page(kva) vm_offset_t kva; { pmap_kremove(kva); kmem_free_wakeup(pager_map, kva, PAGE_SIZE); } vm_object_t vm_pager_object_lookup(pg_list, handle) register struct pagerlst *pg_list; void *handle; { register vm_object_t object; for (object = TAILQ_FIRST(pg_list); object != NULL; object = TAILQ_NEXT(object,pager_object_list)) if (object->handle == handle) return (object); return (NULL); } /* * initialize a physical buffer */ static void initpbuf(struct buf *bp) { bzero(bp, sizeof *bp); bp->b_rcred = NOCRED; bp->b_wcred = NOCRED; bp->b_qindex = QUEUE_NONE; bp->b_data = (caddr_t) (MAXPHYS * (bp - swbuf)) + swapbkva; bp->b_kvabase = bp->b_data; bp->b_kvasize = MAXPHYS; bp->b_vnbufs.le_next = NOLIST; } /* * allocate a physical buffer */ struct buf * getpbuf() { int s; struct buf *bp; s = splbio(); /* get a bp from the swap buffer header pool */ while ((bp = TAILQ_FIRST(&bswlist)) == NULL) { bswneeded = 1; tsleep(&bswneeded, PVM, "wswbuf", 0); } TAILQ_REMOVE(&bswlist, bp, b_freelist); splx(s); initpbuf(bp); return bp; } /* * allocate a physical buffer, if one is available */ struct buf * trypbuf() { int s; struct buf *bp; s = splbio(); if ((bp = TAILQ_FIRST(&bswlist)) == NULL) { splx(s); return NULL; } TAILQ_REMOVE(&bswlist, bp, b_freelist); splx(s); initpbuf(bp); return bp; } /* * release a physical buffer */ void relpbuf(bp) struct buf *bp; { int s; s = splbio(); if (bp->b_rcred != NOCRED) { crfree(bp->b_rcred); bp->b_rcred = NOCRED; } if (bp->b_wcred != NOCRED) { crfree(bp->b_wcred); bp->b_wcred = NOCRED; } if (bp->b_vp) pbrelvp(bp); if (bp->b_flags & B_WANTED) wakeup(bp); TAILQ_INSERT_HEAD(&bswlist, bp, b_freelist); if (bswneeded) { bswneeded = 0; wakeup(&bswneeded); } splx(s); }