/* $OpenBSD: vm_page.c,v 1.12 1998/03/01 11:36:42 niklas Exp $ */ /* $NetBSD: vm_page.c,v 1.41 1998/02/08 18:24:52 thorpej Exp $ */ #define VM_PAGE_ALLOC_MEMORY_STATS /*- * Copyright (c) 1997 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, * NASA Ames Research Center. * * 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 NetBSD * Foundation, Inc. and its contributors. * 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ /* * 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. * * @(#)vm_page.c 8.3 (Berkeley) 3/21/94 * * * 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. */ /* * Resident memory management module. */ #include #include #include #include #include #include #include #include #include #define VERY_LOW_MEM() (cnt.v_free_count <= vm_page_free_reserved) #define KERN_OBJ(object) ((object) == kernel_object || (object) == kmem_object) int vm_page_free_reserved = 10; #if defined(MACHINE_NEW_NONCONTIG) /* * physical memory config is stored in vm_physmem. */ struct vm_physseg vm_physmem[VM_PHYSSEG_MAX]; int vm_nphysseg = 0; static int vm_page_lost_count = 0; /* XXXCDC: DEBUG DEBUG */ #endif #if defined(MACHINE_NONCONTIG) || defined(MACHINE_NEW_NONCONTIG) /* * These variables record the values returned by vm_page_bootstrap, * for debugging purposes. * * The implementation of vm_bootstrap_steal_memory here also uses * them internally. */ static vm_offset_t virtual_space_start; static vm_offset_t virtual_space_end; vm_offset_t vm_bootstrap_steal_memory __P((vm_size_t)); #endif /* * Associated with page of user-allocatable memory is a * page structure. */ struct pglist *vm_page_buckets; /* Array of buckets */ int vm_page_bucket_count = 0; /* How big is array? */ int vm_page_hash_mask; /* Mask for hash function */ simple_lock_data_t bucket_lock; /* lock for all buckets XXX */ #if defined(MACHINE_NEW_NONCONTIG) struct pglist vm_page_bootbucket; /* bootstrap bucket */ #endif struct pglist vm_page_queue_free; struct pglist vm_page_queue_active; struct pglist vm_page_queue_inactive; simple_lock_data_t vm_page_queue_lock; simple_lock_data_t vm_page_queue_free_lock; /* has physical page allocation been initialized? */ boolean_t vm_page_startup_initialized; vm_page_t vm_page_array; #if defined(MACHINE_NEW_NONCONTIG) /* NOTHING NEEDED HERE */ #elif defined(MACHINE_NONCONTIG) /* OLD NONCONTIG CODE: NUKE NUKE NUKE ONCE CONVERTED */ u_long first_page; int vm_page_count; #else /* OLD NCONTIG CODE: NUKE NUKE NUKE ONCE CONVERTED */ long first_page; long last_page; vm_offset_t first_phys_addr; vm_offset_t last_phys_addr; int vm_page_count; #endif vm_size_t page_mask; int page_shift; #if defined(MACHINE_NEW_NONCONTIG) /* * local prototypes */ #if !defined(PMAP_STEAL_MEMORY) static boolean_t vm_page_physget __P((vm_offset_t *)); #endif #endif /* * macros */ /* * vm_page_hash: * * Distributes the object/offset key pair among hash buckets. * * NOTE: This macro depends on vm_page_bucket_count being a power of 2. */ #define vm_page_hash(object, offset) \ (((unsigned long)object+(unsigned long)atop(offset))&vm_page_hash_mask) /* * vm_set_page_size: * * Sets the page size, perhaps based upon the memory * size. Must be called before any use of page-size * dependent functions. * * Sets page_shift and page_mask from cnt.v_page_size. */ void vm_set_page_size() { if (cnt.v_page_size == 0) cnt.v_page_size = DEFAULT_PAGE_SIZE; page_mask = cnt.v_page_size - 1; if ((page_mask & cnt.v_page_size) != 0) panic("vm_set_page_size: page size not a power of two"); for (page_shift = 0; ; page_shift++) if ((1 << page_shift) == cnt.v_page_size) break; } #if defined(MACHINE_NEW_NONCONTIG) /* * vm_page_bootstrap: initialize the resident memory module (called * from vm_mem_init()). * * - startp and endp are out params which return the boundaries of the * free part of the kernel's virtual address space. */ void vm_page_bootstrap(startp, endp) vm_offset_t *startp, *endp; /* OUT, OUT */ { vm_offset_t paddr; vm_page_t pagearray; int lcv, freepages, pagecount, n, i; /* * first init all the locks and queues. */ simple_lock_init(&vm_page_queue_free_lock); simple_lock_init(&vm_page_queue_lock); TAILQ_INIT(&vm_page_queue_free); TAILQ_INIT(&vm_page_queue_active); TAILQ_INIT(&vm_page_queue_inactive); /* * init the => hash table buckets. for now * we just have one bucket (the bootstrap bucket). later on we * will malloc() new buckets as we dynamically resize the hash table. */ vm_page_bucket_count = 1; vm_page_hash_mask = 0; vm_page_buckets = &vm_page_bootbucket; TAILQ_INIT(vm_page_buckets); simple_lock_init(&bucket_lock); /* * before calling this function the MD code is expected to register * some free RAM with the vm_page_physload() function. our job * now is to allocate vm_page structures for this preloaded memory. */ if (vm_nphysseg == 0) panic("vm_page_bootstrap: no memory pre-allocated"); /* * first calculate the number of free pages... note that start/end * are inclusive so you have to add one to get the number of pages. * * note that we use start/end rather than avail_start/avail_end. * this allows us to allocate extra vm_page structures in case we * want to return some memory to the pool after booting. */ freepages = 0; for (lcv = 0; lcv < vm_nphysseg; lcv++) { freepages = freepages + (vm_physmem[lcv].end - vm_physmem[lcv].start); } /* * we now know we have (PAGE_SIZE * freepages) bytes of memory we can * use. for each page of memory we use we need a vm_page structure. * thus, the total number of pages we can use is the total size of * the memory divided by the PAGE_SIZE plus the size of the vm_page * structure. we add one to freepages as a fudge factor to avoid * truncation errors (since we can only allocate in terms of whole * pages). */ pagecount = (PAGE_SIZE * (freepages + 1)) / (PAGE_SIZE + sizeof(struct vm_page)); pagearray = (vm_page_t) vm_bootstrap_steal_memory(pagecount * sizeof(struct vm_page)); bzero(pagearray, pagecount * sizeof(struct vm_page)); /* * now init the page frames */ for (lcv = 0; lcv < vm_nphysseg; lcv++) { n = vm_physmem[lcv].end - vm_physmem[lcv].start; if (n > pagecount) { printf("vm_init: lost %d page(s) in init\n", n - pagecount); vm_page_lost_count += (n - pagecount); n = pagecount; } /* set up page array pointers */ vm_physmem[lcv].pgs = pagearray; pagearray += n; pagecount -= n; vm_physmem[lcv].lastpg = vm_physmem[lcv].pgs + (n - 1); /* init and free vm_pages (we've already bzero'd them) */ paddr = ptoa(vm_physmem[lcv].start); for (i = 0; i < n; i++, paddr += PAGE_SIZE) { vm_physmem[lcv].pgs[i].phys_addr = paddr; if (atop(paddr) >= vm_physmem[lcv].avail_start && atop(paddr) <= vm_physmem[lcv].avail_end) vm_page_free(&vm_physmem[lcv].pgs[i]); } } /* * pass up the values of virtual_space_start and virtual_space_end * (obtained by vm_bootstrap_steal_memory) to the upper layers of * the VM. */ *startp = round_page(virtual_space_start); *endp = trunc_page(virtual_space_end); /* * init pagedaemon lock */ simple_lock_init(&vm_pages_needed_lock); } /* * vm_bootstrap_steal_memory: steal memory from physmem for bootstrapping */ vm_offset_t vm_bootstrap_steal_memory(size) vm_size_t size; { #if defined(PMAP_STEAL_MEMORY) vm_offset_t addr; /* * Defer this to machine-dependent code; we may need to allocate * from a direct-mapped segment. */ addr = pmap_steal_memory(size, &virtual_space_start, &virtual_space_end); /* round it the way we like it */ virtual_space_start = round_page(virtual_space_start); virtual_space_end = trunc_page(virtual_space_end); return (addr); #else /* ! PMAP_STEAL_MEMORY */ vm_offset_t addr, vaddr, paddr; /* round to page size */ size = round_page(size); /* * on first call to this function init ourselves. we detect this * by checking virtual_space_start/end which are in the zero'd BSS * area. */ if (virtual_space_start == virtual_space_end) { pmap_virtual_space(&virtual_space_start, &virtual_space_end); /* round it the way we like it */ virtual_space_start = round_page(virtual_space_start); virtual_space_end = trunc_page(virtual_space_end); } /* * allocate virtual memory for this request */ addr = virtual_space_start; virtual_space_start += size; /* * allocate and mapin physical pages to back new virtual pages */ for (vaddr = round_page(addr); vaddr < addr + size; vaddr += PAGE_SIZE) { if (!vm_page_physget(&paddr)) panic("vm_bootstrap_steal_memory: out of memory"); /* XXX: should be wired, but some pmaps don't like that ... */ pmap_enter(pmap_kernel(), vaddr, paddr, VM_PROT_READ|VM_PROT_WRITE, FALSE); } return(addr); #endif /* PMAP_STEAL_MEMORY */ } #if !defined(PMAP_STEAL_MEMORY) /* * vm_page_physget: "steal" one page from the vm_physmem structure. * * - attempt to allocate it off the end of a segment in which the "avail" * values match the start/end values. if we can't do that, then we * will advance both values (making them equal, and removing some * vm_page structures from the non-avail area). * - return false if out of memory. */ static boolean_t vm_page_physget(paddrp) vm_offset_t *paddrp; { int lcv, x; /* pass 1: try allocating from a matching end */ #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST) for (lcv = vm_nphysseg - 1 ; lcv >= 0 ; lcv--) #else for (lcv = 0 ; lcv < vm_nphysseg ; lcv++) #endif { if (vm_physmem[lcv].pgs) panic("vm_page_physget: called _after_ bootstrap"); /* try from front */ if (vm_physmem[lcv].avail_start == vm_physmem[lcv].start && vm_physmem[lcv].avail_start < vm_physmem[lcv].avail_end) { *paddrp = ptoa(vm_physmem[lcv].avail_start); vm_physmem[lcv].avail_start++; vm_physmem[lcv].start++; /* nothing left? nuke it */ if (vm_physmem[lcv].avail_start == vm_physmem[lcv].end) { if (vm_nphysseg == 1) panic("vm_page_physget: out of memory!"); vm_nphysseg--; for (x = lcv; x < vm_nphysseg; x++) /* structure copy */ vm_physmem[x] = vm_physmem[x+1]; } return(TRUE); } /* try from rear */ if (vm_physmem[lcv].avail_end == vm_physmem[lcv].end && vm_physmem[lcv].avail_start < vm_physmem[lcv].avail_end) { *paddrp = ptoa(vm_physmem[lcv].avail_end - 1); vm_physmem[lcv].avail_end--; vm_physmem[lcv].end--; /* nothing left? nuke it */ if (vm_physmem[lcv].avail_end == vm_physmem[lcv].start) { if (vm_nphysseg == 1) panic("vm_page_physget: out of memory!"); vm_nphysseg--; for (x = lcv; x < vm_nphysseg; x++) /* structure copy */ vm_physmem[x] = vm_physmem[x+1]; } return(TRUE); } } /* pass2: forget about matching ends, just allocate something */ #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST) for (lcv = vm_nphysseg - 1 ; lcv >= 0 ; lcv--) #else for (lcv = 0 ; lcv < vm_nphysseg ; lcv++) #endif { /* any room in this bank? */ if (vm_physmem[lcv].avail_start >= vm_physmem[lcv].avail_end) continue; /* nope */ *paddrp = ptoa(vm_physmem[lcv].avail_start); vm_physmem[lcv].avail_start++; vm_physmem[lcv].start = vm_physmem[lcv].avail_start; /* truncate! */ /* nothing left? nuke it */ if (vm_physmem[lcv].avail_start == vm_physmem[lcv].end) { if (vm_nphysseg == 1) panic("vm_page_physget: out of memory!"); vm_nphysseg--; for (x = lcv; x < vm_nphysseg; x++) vm_physmem[x] = vm_physmem[x+1]; /* structure copy */ } return(TRUE); } return(FALSE); /* whoops! */ } #endif /* ! PMAP_STEAL_MEMORY */ /* * vm_page_physload: load physical memory into VM system * * - all args are PFs * - all pages in start/end get vm_page structures * - areas marked by avail_start/avail_end get added to the free page pool * - we are limited to VM_PHYSSEG_MAX physical memory segments */ void vm_page_physload(start, end, avail_start, avail_end) vm_offset_t start, end, avail_start, avail_end; { struct vm_page *pgs; struct vm_physseg *ps; int preload, lcv, npages, x; if (page_shift == 0) panic("vm_page_physload: page size not set!"); /* * do we have room? */ if (vm_nphysseg == VM_PHYSSEG_MAX) { printf("vm_page_physload: unable to load physical memory segment\n"); printf("\t%d segments allocated, ignoring 0x%lx -> 0x%lx\n", VM_PHYSSEG_MAX, start, end); return; } /* * check to see if this is a "preload" (i.e. vm_mem_init hasn't been * called yet, so malloc is not available). */ for (lcv = 0; lcv < vm_nphysseg; lcv++) { if (vm_physmem[lcv].pgs) break; } preload = (lcv == vm_nphysseg); /* * if VM is already running, attempt to malloc() vm_page structures */ if (!preload) { #if defined(VM_PHYSSEG_NOADD) panic("vm_page_physload: tried to add RAM after vm_mem_init"); #else /* XXXCDC: need some sort of lockout for this case */ vm_offset_t paddr; /* # of pages */ npages = end - start; MALLOC(pgs, struct vm_page *, sizeof(struct vm_page) * npages, M_VMPAGE, M_NOWAIT); if (pgs == NULL) { printf("vm_page_physload: can not malloc vm_page structs for segment\n"); printf("\tignoring 0x%lx -> 0x%lx\n", start, end); return; } /* zero data, init phys_addr, and free pages */ bzero(pgs, sizeof(struct vm_page) * npages); for (lcv = 0, paddr = ptoa(start); lcv < npages; lcv++, paddr += PAGE_SIZE) { pgs[lcv].phys_addr = paddr; if (atop(paddr) >= avail_start && atop(paddr) <= avail_end) vm_page_free(&pgs[i]); } /* XXXCDC: incomplete: need to update v_free_count, what else? */ /* XXXCDC: need hook to tell pmap to rebuild pv_list, etc... */ #endif } else { /* XXX/gcc complains if these don't get init'd */ pgs = NULL; npages = 0; } /* * now insert us in the proper place in vm_physmem[] */ #if (VM_PHYSSEG_STRAT == VM_PSTRAT_RANDOM) /* random: put it at the end (easy!) */ ps = &vm_physmem[vm_nphysseg]; #else #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BSEARCH) /* sort by address for binary search */ for (lcv = 0 ; lcv < vm_nphysseg ; lcv++) if (start < vm_physmem[lcv].start) break; ps = &vm_physmem[lcv]; /* move back other entries, if necessary ... */ for (x = vm_nphysseg ; x > lcv ; x--) /* structure copy */ vm_physmem[x] = vm_physmem[x - 1]; #else #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST) /* sort by largest segment first */ for (lcv = 0 ; lcv < vm_nphysseg ; lcv++) if ((end - start) > (vm_physmem[lcv].end - vm_physmem[lcv].start)) break; ps = &vm_physmem[lcv]; /* move back other entries, if necessary ... */ for (x = vm_nphysseg ; x > lcv ; x--) /* structure copy */ vm_physmem[x] = vm_physmem[x - 1]; #else panic("vm_page_physload: unknown physseg strategy selected!"); #endif #endif #endif ps->start = start; ps->end = end; ps->avail_start = avail_start; ps->avail_end = avail_end; if (preload) { ps->pgs = NULL; } else { ps->pgs = pgs; ps->lastpg = pgs + npages - 1; } vm_nphysseg++; /* * done! */ return; } /* * vm_page_physrehash: reallocate hash table based on number of * free pages. */ void vm_page_physrehash() { struct pglist *newbuckets, *oldbuckets; struct vm_page *pg; int freepages, lcv, bucketcount, s, oldcount; /* * compute number of pages that can go in the free pool */ freepages = 0; for (lcv = 0; lcv < vm_nphysseg; lcv++) freepages = freepages + (vm_physmem[lcv].avail_end - vm_physmem[lcv].avail_start); /* * compute number of buckets needed for this number of pages */ bucketcount = 1; while (bucketcount < freepages) bucketcount = bucketcount * 2; /* * malloc new buckets */ MALLOC(newbuckets, struct pglist *, sizeof(struct pglist) * bucketcount, M_VMPBUCKET, M_NOWAIT); if (newbuckets == NULL) { printf("vm_page_physrehash: WARNING: could not grow page hash table\n"); return; } for (lcv = 0; lcv < bucketcount; lcv++) TAILQ_INIT(&newbuckets[lcv]); /* * now replace the old buckets with the new ones and rehash everything */ s = splimp(); simple_lock(&bucket_lock); /* swap old for new ... */ oldbuckets = vm_page_buckets; oldcount = vm_page_bucket_count; vm_page_buckets = newbuckets; vm_page_bucket_count = bucketcount; vm_page_hash_mask = bucketcount - 1; /* power of 2 */ /* ... and rehash */ for (lcv = 0 ; lcv < oldcount ; lcv++) { while ((pg = oldbuckets[lcv].tqh_first) != NULL) { TAILQ_REMOVE(&oldbuckets[lcv], pg, hashq); TAILQ_INSERT_TAIL(&vm_page_buckets[ vm_page_hash(pg->object, pg->offset)], pg, hashq); } } simple_unlock(&bucket_lock); splx(s); /* * free old bucket array if we malloc'd it previously */ if (oldbuckets != &vm_page_bootbucket) FREE(oldbuckets, M_VMPBUCKET); /* * done */ return; } #if 1 /* XXXCDC: TMP TMP TMP DEBUG DEBUG DEBUG */ void vm_page_physdump __P((void)); /* SHUT UP GCC */ /* call from DDB */ void vm_page_physdump() { int lcv; printf("rehash: physical memory config [segs=%d of %d]:\n", vm_nphysseg, VM_PHYSSEG_MAX); for (lcv = 0 ; lcv < vm_nphysseg ; lcv++) printf("0x%lx->0x%lx [0x%lx->0x%lx]\n", vm_physmem[lcv].start, vm_physmem[lcv].end, vm_physmem[lcv].avail_start, vm_physmem[lcv].avail_end); printf("STRATEGY = "); switch (VM_PHYSSEG_STRAT) { case VM_PSTRAT_RANDOM: printf("RANDOM\n"); break; case VM_PSTRAT_BSEARCH: printf("BSEARCH\n"); break; case VM_PSTRAT_BIGFIRST: printf("BIGFIRST\n"); break; default: printf("<>!!!!\n"); } printf("number of buckets = %d\n", vm_page_bucket_count); printf("number of lost pages = %d\n", vm_page_lost_count); } #endif #elif defined(MACHINE_NONCONTIG) /* OLD NONCONTIG CODE: NUKE NUKE NUKE ONCE CONVERTED */ /* * We implement vm_page_bootstrap and vm_bootstrap_steal_memory with * the help of two simpler functions: * * pmap_virtual_space and pmap_next_page */ /* * vm_page_bootstrap: * * Initializes the resident memory module. * * Allocates memory for the page cells, and * for the object/offset-to-page hash table headers. * Each page cell is initialized and placed on the free list. * Returns the range of available kernel virtual memory. */ void vm_page_bootstrap(startp, endp) vm_offset_t *startp; vm_offset_t *endp; { unsigned int i, freepages; register struct pglist *bucket; vm_offset_t paddr; extern vm_offset_t kentry_data; extern vm_size_t kentry_data_size; /* * Initialize the locks */ simple_lock_init(&vm_page_queue_free_lock); simple_lock_init(&vm_page_queue_lock); /* * Initialize the queue headers for the free queue, * the active queue and the inactive queue. */ TAILQ_INIT(&vm_page_queue_free); TAILQ_INIT(&vm_page_queue_active); TAILQ_INIT(&vm_page_queue_inactive); /* * Pre-allocate maps and map entries that cannot be dynamically * allocated via malloc(). The maps include the kernel_map and * kmem_map which must be initialized before malloc() will * work (obviously). Also could include pager maps which would * be allocated before kmeminit. * * Allow some kernel map entries... this should be plenty * since people shouldn't be cluttering up the kernel * map (they should use their own maps). */ kentry_data_size = round_page(MAX_KMAP*sizeof(struct vm_map) + MAX_KMAPENT*sizeof(struct vm_map_entry)); kentry_data = vm_bootstrap_steal_memory(kentry_data_size); /* * Validate these zone addresses. */ bzero((caddr_t) kentry_data, kentry_data_size); /* * Allocate (and initialize) the virtual-to-physical * table hash buckets. * * The number of buckets MUST BE a power of 2, and * the actual value is the next power of 2 greater * than the number of physical pages in the system. * * Note: * This computation can be tweaked if desired. */ if (vm_page_bucket_count == 0) { unsigned int npages = pmap_free_pages(); vm_page_bucket_count = 1; while (vm_page_bucket_count < npages) vm_page_bucket_count <<= 1; } vm_page_hash_mask = vm_page_bucket_count - 1; vm_page_buckets = (struct pglist *) vm_bootstrap_steal_memory(vm_page_bucket_count * sizeof(*vm_page_buckets)); bucket = vm_page_buckets; for (i = vm_page_bucket_count; i--;) { TAILQ_INIT(bucket); bucket++; } simple_lock_init(&bucket_lock); /* * We calculate how many page frames we will have and * then allocate the page structures in one chunk. * The calculation is non-trivial. We want: * * vmpages > (freepages - (vmpages / sizeof(vm_page_t))) * * ...which, with some algebra, becomes: * * vmpages > (freepages * sizeof(...) / (1 + sizeof(...))) * * The value of vm_page_count need not be exact, but must * be large enough so vm_page_array handles the index range. */ freepages = pmap_free_pages(); /* Fudge slightly to deal with truncation error. */ freepages += 1; /* fudge */ vm_page_count = (PAGE_SIZE * freepages) / (PAGE_SIZE + sizeof(*vm_page_array)); vm_page_array = (vm_page_t) vm_bootstrap_steal_memory(vm_page_count * sizeof(*vm_page_array)); bzero(vm_page_array, vm_page_count * sizeof(*vm_page_array)); #ifdef DIAGNOSTIC /* * Initialize everything in case the holes are stepped in, * and set PA to something that will cause a panic... */ for (i = 0; i < vm_page_count; i++) vm_page_array[i].phys_addr = 0xdeadbeef; #endif /* * Initialize the page frames. Note that some page * indices may not be usable when pmap_free_pages() * counts pages in a hole. */ if (!pmap_next_page(&paddr)) panic("vm_page_bootstrap: can't get first page"); first_page = pmap_page_index(paddr); for (i = 0;;) { /* * Initialize a page array element. */ VM_PAGE_INIT(&vm_page_array[i], NULL, NULL); vm_page_array[i].phys_addr = paddr; vm_page_free(&vm_page_array[i]); /* * Are there any more physical pages? */ if (!pmap_next_page(&paddr)) break; i = pmap_page_index(paddr) - first_page; /* * Don't trust pmap_page_index()... */ if ( #if 0 i < 0 || /* can't happen, i is unsigned */ #endif i >= vm_page_count) panic("vm_page_bootstrap: bad i = 0x%x", i); } /* * Make sure we have nice, round values. */ virtual_space_start = round_page(virtual_space_start); virtual_space_end = trunc_page(virtual_space_end); *startp = virtual_space_start; *endp = virtual_space_end; simple_lock_init(&vm_pages_needed_lock); } vm_offset_t vm_bootstrap_steal_memory(size) vm_size_t size; { vm_offset_t addr, vaddr, paddr; /* * We round to page size. */ size = round_page(size); /* * If this is the first call to vm_bootstrap_steal_memory, * we have to initialize ourself. */ if (virtual_space_start == virtual_space_end) { pmap_virtual_space(&virtual_space_start, &virtual_space_end); /* * The initial values must be aligned properly, and * we don't trust the pmap module to do it right. */ virtual_space_start = round_page(virtual_space_start); virtual_space_end = trunc_page(virtual_space_end); } /* * Allocate virtual memory for this request. */ addr = virtual_space_start; virtual_space_start += size; /* * Allocate and map physical pages to back new virtual pages. */ for (vaddr = round_page(addr); vaddr < addr + size; vaddr += PAGE_SIZE) { if (!pmap_next_page(&paddr)) panic("vm_bootstrap_steal_memory"); /* * XXX Logically, these mappings should be wired, * but some pmap modules barf if they are. */ pmap_enter(pmap_kernel(), vaddr, paddr, VM_PROT_READ|VM_PROT_WRITE, FALSE); } return addr; } #else /* MACHINE_NONCONTIG */ /* OLD CONTIG CODE: NUKE NUKE NUKE ONCE CONVERTED */ /* * vm_page_startup: * * Initializes the resident memory module. * * Allocates memory for the page cells, and * for the object/offset-to-page hash table headers. * Each page cell is initialized and placed on the free list. */ void vm_page_startup(start, end) vm_offset_t *start; vm_offset_t *end; { register vm_page_t m; register struct pglist *bucket; int npages; int i; vm_offset_t pa; extern vm_offset_t kentry_data; extern vm_size_t kentry_data_size; /* * Initialize the locks */ simple_lock_init(&vm_page_queue_free_lock); simple_lock_init(&vm_page_queue_lock); /* * Initialize the queue headers for the free queue, * the active queue and the inactive queue. */ TAILQ_INIT(&vm_page_queue_free); TAILQ_INIT(&vm_page_queue_active); TAILQ_INIT(&vm_page_queue_inactive); /* * Calculate the number of hash table buckets. * * The number of buckets MUST BE a power of 2, and * the actual value is the next power of 2 greater * than the number of physical pages in the system. * * Note: * This computation can be tweaked if desired. */ if (vm_page_bucket_count == 0) { vm_page_bucket_count = 1; while (vm_page_bucket_count < atop(*end - *start)) vm_page_bucket_count <<= 1; } vm_page_hash_mask = vm_page_bucket_count - 1; /* * Allocate (and initialize) the hash table buckets. */ vm_page_buckets = (struct pglist *) pmap_bootstrap_alloc(vm_page_bucket_count * sizeof(struct pglist)); bucket = vm_page_buckets; for (i = vm_page_bucket_count; i--;) { TAILQ_INIT(bucket); bucket++; } simple_lock_init(&bucket_lock); /* * Truncate the remainder of physical memory to our page size. */ *end = trunc_page(*end); /* * Pre-allocate maps and map entries that cannot be dynamically * allocated via malloc(). The maps include the kernel_map and * kmem_map which must be initialized before malloc() will * work (obviously). Also could include pager maps which would * be allocated before kmeminit. * * Allow some kernel map entries... this should be plenty * since people shouldn't be cluttering up the kernel * map (they should use their own maps). */ kentry_data_size = round_page(MAX_KMAP*sizeof(struct vm_map) + MAX_KMAPENT*sizeof(struct vm_map_entry)); kentry_data = (vm_offset_t) pmap_bootstrap_alloc(kentry_data_size); /* * Compute the number of pages of memory that will be * available for use (taking into account the overhead * of a page structure per page). */ cnt.v_free_count = vm_page_count = (*end - *start + sizeof(struct vm_page)) / (PAGE_SIZE + sizeof(struct vm_page)); /* * Record the extent of physical memory that the * virtual memory system manages. */ first_page = *start; first_page += vm_page_count * sizeof(struct vm_page); first_page = atop(round_page(first_page)); last_page = first_page + vm_page_count - 1; first_phys_addr = ptoa(first_page); last_phys_addr = ptoa(last_page) + PAGE_MASK; /* * Allocate and clear the mem entry structures. */ m = vm_page_array = (vm_page_t) pmap_bootstrap_alloc(vm_page_count * sizeof(struct vm_page)); bzero(vm_page_array, vm_page_count * sizeof(struct vm_page)); /* * Initialize the mem entry structures now, and * put them in the free queue. */ pa = first_phys_addr; npages = vm_page_count; while (npages--) { m->flags = PG_FREE; m->object = NULL; m->phys_addr = pa; TAILQ_INSERT_TAIL(&vm_page_queue_free, m, pageq); m++; pa += PAGE_SIZE; } /* * Initialize vm_pages_needed lock here - don't wait for pageout * daemon XXX */ simple_lock_init(&vm_pages_needed_lock); /* from now on, pmap_bootstrap_alloc can't be used */ vm_page_startup_initialized = TRUE; } #endif /* MACHINE_NONCONTIG */ /* * vm_page_insert: [ internal use only ] * * Inserts the given mem entry into the object/object-page * table and object list. * * The object and page must be locked. */ void vm_page_insert(mem, object, offset) register vm_page_t mem; register vm_object_t object; register vm_offset_t offset; { register struct pglist *bucket; int spl; VM_PAGE_CHECK(mem); if (mem->flags & PG_TABLED) panic("vm_page_insert: already inserted"); /* * Record the object/offset pair in this page */ mem->object = object; mem->offset = offset; /* * Insert it into the object_object/offset hash table */ bucket = &vm_page_buckets[vm_page_hash(object, offset)]; spl = splimp(); simple_lock(&bucket_lock); TAILQ_INSERT_TAIL(bucket, mem, hashq); simple_unlock(&bucket_lock); (void) splx(spl); /* * Now link into the object's list of backed pages. */ TAILQ_INSERT_TAIL(&object->memq, mem, listq); mem->flags |= PG_TABLED; /* * And show that the object has one more resident * page. */ object->resident_page_count++; } /* * vm_page_remove: [ internal use only ] * XXX: used by device pager as well * * Removes the given mem entry from the object/offset-page * table and the object page list. * * The object and page must be locked. */ void vm_page_remove(mem) register vm_page_t mem; { register struct pglist *bucket; int spl; VM_PAGE_CHECK(mem); #ifdef DIAGNOSTIC if (mem->flags & PG_FAULTING) panic("vm_page_remove: page is faulting"); #endif if (!(mem->flags & PG_TABLED)) return; /* * Remove from the object_object/offset hash table */ bucket = &vm_page_buckets[vm_page_hash(mem->object, mem->offset)]; spl = splimp(); simple_lock(&bucket_lock); TAILQ_REMOVE(bucket, mem, hashq); simple_unlock(&bucket_lock); (void) splx(spl); /* * Now remove from the object's list of backed pages. */ TAILQ_REMOVE(&mem->object->memq, mem, listq); /* * And show that the object has one fewer resident * page. */ mem->object->resident_page_count--; mem->flags &= ~PG_TABLED; } /* * vm_page_lookup: * * Returns the page associated with the object/offset * pair specified; if none is found, NULL is returned. * * The object must be locked. No side effects. */ vm_page_t vm_page_lookup(object, offset) register vm_object_t object; register vm_offset_t offset; { register vm_page_t mem; register struct pglist *bucket; int spl; /* * Search the hash table for this object/offset pair */ bucket = &vm_page_buckets[vm_page_hash(object, offset)]; spl = splimp(); simple_lock(&bucket_lock); for (mem = bucket->tqh_first; mem != NULL; mem = mem->hashq.tqe_next) { VM_PAGE_CHECK(mem); if ((mem->object == object) && (mem->offset == offset)) { simple_unlock(&bucket_lock); splx(spl); return(mem); } } simple_unlock(&bucket_lock); splx(spl); return(NULL); } /* * vm_page_rename: * * Move the given memory entry from its * current object to the specified target object/offset. * * The object must be locked. */ void vm_page_rename(mem, new_object, new_offset) register vm_page_t mem; register vm_object_t new_object; vm_offset_t new_offset; { if (mem->object == new_object) return; vm_page_lock_queues(); /* keep page from moving out from under pageout daemon */ vm_page_remove(mem); vm_page_insert(mem, new_object, new_offset); vm_page_unlock_queues(); } /* * vm_page_alloc: * * Allocate and return a memory cell associated * with this VM object/offset pair. * * Object must be locked. */ vm_page_t vm_page_alloc(object, offset) vm_object_t object; vm_offset_t offset; { register vm_page_t mem; int spl; spl = splimp(); /* XXX */ simple_lock(&vm_page_queue_free_lock); mem = vm_page_queue_free.tqh_first; if (VERY_LOW_MEM()) { if ((!KERN_OBJ(object) && curproc != pageout_daemon) || mem == NULL) { simple_unlock(&vm_page_queue_free_lock); splx(spl); return(NULL); } } #ifdef DIAGNOSTIC if (mem == NULL) /* because we now depend on VERY_LOW_MEM() */ panic("vm_page_alloc"); #endif TAILQ_REMOVE(&vm_page_queue_free, mem, pageq); cnt.v_free_count--; simple_unlock(&vm_page_queue_free_lock); splx(spl); VM_PAGE_INIT(mem, object, offset); /* * Decide if we should poke the pageout daemon. * We do this if the free count is less than the low * water mark, or if the free count is less than the high * water mark (but above the low water mark) and the inactive * count is less than its target. * * We don't have the counts locked ... if they change a little, * it doesn't really matter. */ if (cnt.v_free_count < cnt.v_free_min || (cnt.v_free_count < cnt.v_free_target && cnt.v_inactive_count < cnt.v_inactive_target)) thread_wakeup(&vm_pages_needed); return (mem); } /* * vm_page_free: * * Returns the given page to the free list, * disassociating it with any VM object. * * Object and page must be locked prior to entry. */ void vm_page_free(mem) register vm_page_t mem; { vm_page_remove(mem); if (mem->flags & PG_ACTIVE) { TAILQ_REMOVE(&vm_page_queue_active, mem, pageq); mem->flags &= ~PG_ACTIVE; cnt.v_active_count--; } if (mem->flags & PG_INACTIVE) { TAILQ_REMOVE(&vm_page_queue_inactive, mem, pageq); mem->flags &= ~PG_INACTIVE; cnt.v_inactive_count--; } if (!(mem->flags & PG_FICTITIOUS)) { int spl; spl = splimp(); simple_lock(&vm_page_queue_free_lock); mem->flags |= PG_FREE; TAILQ_INSERT_TAIL(&vm_page_queue_free, mem, pageq); cnt.v_free_count++; simple_unlock(&vm_page_queue_free_lock); splx(spl); } } /* * vm_page_wire: * * Mark this page as wired down by yet * another map, removing it from paging queues * as necessary. * * The page queues must be locked. */ void vm_page_wire(mem) register vm_page_t mem; { VM_PAGE_CHECK(mem); if (mem->wire_count == 0) { if (mem->flags & PG_ACTIVE) { TAILQ_REMOVE(&vm_page_queue_active, mem, pageq); cnt.v_active_count--; mem->flags &= ~PG_ACTIVE; } if (mem->flags & PG_INACTIVE) { TAILQ_REMOVE(&vm_page_queue_inactive, mem, pageq); cnt.v_inactive_count--; mem->flags &= ~PG_INACTIVE; } cnt.v_wire_count++; } mem->wire_count++; } /* * vm_page_unwire: * * Release one wiring of this page, potentially * enabling it to be paged again. * * The page queues must be locked. */ void vm_page_unwire(mem) register vm_page_t mem; { VM_PAGE_CHECK(mem); mem->wire_count--; if (mem->wire_count == 0) { TAILQ_INSERT_TAIL(&vm_page_queue_active, mem, pageq); cnt.v_active_count++; mem->flags |= PG_ACTIVE; cnt.v_wire_count--; } } /* * vm_page_deactivate: * * Returns the given page to the inactive list, * indicating that no physical maps have access * to this page. [Used by the physical mapping system.] * * The page queues must be locked. */ void vm_page_deactivate(m) register vm_page_t m; { VM_PAGE_CHECK(m); /* * Only move active pages -- ignore locked or already * inactive ones. */ if (m->flags & PG_ACTIVE) { TAILQ_REMOVE(&vm_page_queue_active, m, pageq); m->flags &= ~PG_ACTIVE; cnt.v_active_count--; goto deact; } if ((m->flags & PG_INACTIVE) == 0) { deact: TAILQ_INSERT_TAIL(&vm_page_queue_inactive, m, pageq); m->flags |= PG_INACTIVE; cnt.v_inactive_count++; pmap_clear_reference(VM_PAGE_TO_PHYS(m)); if (pmap_is_modified(VM_PAGE_TO_PHYS(m))) m->flags &= ~PG_CLEAN; if (m->flags & PG_CLEAN) m->flags &= ~PG_LAUNDRY; else m->flags |= PG_LAUNDRY; } } /* * vm_page_activate: * * Put the specified page on the active list (if appropriate). * * The page queues must be locked. */ void vm_page_activate(m) register vm_page_t m; { VM_PAGE_CHECK(m); if (m->flags & PG_INACTIVE) { TAILQ_REMOVE(&vm_page_queue_inactive, m, pageq); m->flags &= ~PG_INACTIVE; cnt.v_inactive_count--; } if (m->wire_count == 0) { if (m->flags & PG_ACTIVE) panic("vm_page_activate: already active"); TAILQ_INSERT_TAIL(&vm_page_queue_active, m, pageq); m->flags |= PG_ACTIVE; cnt.v_active_count++; } } /* * vm_page_zero_fill: * * Zero-fill the specified page. * Written as a standard pagein routine, to * be used by the zero-fill object. */ boolean_t vm_page_zero_fill(m) vm_page_t m; { VM_PAGE_CHECK(m); m->flags &= ~PG_CLEAN; pmap_zero_page(VM_PAGE_TO_PHYS(m)); return(TRUE); } /* * vm_page_copy: * * Copy one page to another */ void vm_page_copy(src_m, dest_m) vm_page_t src_m; vm_page_t dest_m; { VM_PAGE_CHECK(src_m); VM_PAGE_CHECK(dest_m); dest_m->flags &= ~PG_CLEAN; pmap_copy_page(VM_PAGE_TO_PHYS(src_m), VM_PAGE_TO_PHYS(dest_m)); } #ifdef VM_PAGE_ALLOC_MEMORY_STATS #define STAT_INCR(v) (v)++ #define STAT_DECR(v) do { \ if ((v) == 0) \ printf("%s:%d -- Already 0!\n", __FILE__, __LINE__); \ else \ (v)--; \ } while (0) u_long vm_page_alloc_memory_npages; #else #define STAT_INCR(v) #define STAT_DECR(v) #endif /* * vm_page_alloc_memory: * * Allocate physical pages conforming to the restrictions * provided: * * size The size of the allocation, * rounded to page size. * * low The low address of the allowed * allocation range. * * high The high address of the allowed * allocation range. * * alignment Allocation must be aligned to this * power-of-two boundary. * * boundary No segment in the allocation may * cross this power-of-two boundary * (relative to zero). * * The allocated pages are placed at the tail of `rlist'; `rlist' * is assumed to be properly initialized by the caller. The * number of memory segments that the allocated memory may * occupy is specified in the `nsegs' arguement. * * Returns 0 on success or an errno value to indicate mode * of failure. * * XXX This implementation could be improved. It only * XXX allocates a single segment. */ int vm_page_alloc_memory(size, low, high, alignment, boundary, rlist, nsegs, waitok) vm_size_t size; vm_offset_t low, high, alignment, boundary; struct pglist *rlist; int nsegs, waitok; { vm_offset_t try, idxpa, lastidxpa; #if defined(MACHINE_NEW_NONCONTIG) int psi; struct vm_page *vm_page_array; #endif int s, tryidx, idx, end, error; vm_page_t m; u_long pagemask; #ifdef DEBUG vm_page_t tp; #endif #ifdef DIAGNOSTIC if ((alignment & (alignment - 1)) != 0) panic("vm_page_alloc_memory: alignment must be power of 2"); if ((boundary & (boundary - 1)) != 0) panic("vm_page_alloc_memory: boundary must be power of 2"); #endif /* * Our allocations are always page granularity, so our alignment * must be, too. */ if (alignment < PAGE_SIZE) alignment = PAGE_SIZE; size = round_page(size); try = roundup(low, alignment); if (boundary != 0 && boundary < size) return (EINVAL); pagemask = ~(boundary - 1); /* Default to "lose". */ error = ENOMEM; /* * Block all memory allocation and lock the free list. */ s = splimp(); simple_lock(&vm_page_queue_free_lock); /* Are there even any free pages? */ if (vm_page_queue_free.tqh_first == NULL) goto out; for (;; try += alignment) { if (try + size > high) { /* * We've run past the allowable range. */ goto out; } /* * Make sure this is a managed physical page. */ #if defined(MACHINE_NEW_NONCONTIG) if ((psi = vm_physseg_find(atop(try), &idx)) == -1) continue; /* managed? */ if (vm_physseg_find(atop(try + size), NULL) != psi) continue; /* end must be in this segment */ tryidx = idx; end = idx + (size / PAGE_SIZE); vm_page_array = vm_physmem[psi].pgs; /* XXX: emulates old global vm_page_array */ #else if (IS_VM_PHYSADDR(try) == 0) continue; tryidx = idx = VM_PAGE_INDEX(try); end = idx + (size / PAGE_SIZE); if (end > vm_page_count) { /* * No more physical memory. */ goto out; } #endif /* * Found a suitable starting page. See of the range * is free. */ for (; idx < end; idx++) { if (VM_PAGE_IS_FREE(&vm_page_array[idx]) == 0) { /* * Page not available. */ break; } idxpa = VM_PAGE_TO_PHYS(&vm_page_array[idx]); #if !defined(MACHINE_NEW_NONCONTIG) /* * Make sure this is a managed physical page. * XXX Necessary? I guess only if there * XXX are holes in the vm_page_array[]. */ if (IS_VM_PHYSADDR(idxpa) == 0) break; #endif if (idx > tryidx) { lastidxpa = VM_PAGE_TO_PHYS(&vm_page_array[idx - 1]); if ((lastidxpa + PAGE_SIZE) != idxpa) { /* * Region not contiguous. */ break; } if (boundary != 0 && ((lastidxpa ^ idxpa) & pagemask) != 0) { /* * Region crosses boundary. */ break; } } } if (idx == end) { /* * Woo hoo! Found one. */ break; } } /* * Okay, we have a chunk of memory that conforms to * the requested constraints. */ idx = tryidx; while (idx < end) { m = &vm_page_array[idx]; #ifdef DEBUG for (tp = vm_page_queue_free.tqh_first; tp != NULL; tp = tp->pageq.tqe_next) { if (tp == m) break; } if (tp == NULL) panic("vm_page_alloc_memory: page not on freelist"); #endif TAILQ_REMOVE(&vm_page_queue_free, m, pageq); cnt.v_free_count--; m->flags = PG_CLEAN; m->object = NULL; m->wire_count = 0; TAILQ_INSERT_TAIL(rlist, m, pageq); idx++; STAT_INCR(vm_page_alloc_memory_npages); } error = 0; out: simple_unlock(&vm_page_queue_free_lock); splx(s); return (error); } /* * vm_page_free_memory: * * Free a list of pages previously allocated by vm_page_alloc_memory(). * The pages are assumed to have no mappings. */ void vm_page_free_memory(list) struct pglist *list; { vm_page_t m; int s; /* * Block all memory allocation and lock the free list. */ s = splimp(); simple_lock(&vm_page_queue_free_lock); while ((m = list->tqh_first) != NULL) { TAILQ_REMOVE(list, m, pageq); m->flags = PG_FREE; TAILQ_INSERT_TAIL(&vm_page_queue_free, m, pageq); cnt.v_free_count++; STAT_DECR(vm_page_alloc_memory_npages); } simple_unlock(&vm_page_queue_free_lock); splx(s); } #if defined(MACHINE_NONCONTIG) && !defined(MACHINE_PAGES) /* * We implement pmap_steal_memory and pmap_startup with the help * of two simpler functions, pmap_virtual_space and pmap_next_page. */ vm_offset_t pmap_steal_memory(size) vm_size_t size; { vm_offset_t addr, vaddr, paddr; #ifdef i386 /* XXX i386 calls pmap_steal_memory before vm_mem_init() */ if (cnt.v_page_size == 0) /* XXX */ vm_set_page_size(); #endif /* * We round the size to an integer multiple. */ size = (size + 3) &~ 3; /* XXX */ /* * If this is the first call to pmap_steal_memory, * we have to initialize ourself. */ if (virtual_space_start == virtual_space_end) { pmap_virtual_space(&virtual_space_start, &virtual_space_end); /* * The initial values must be aligned properly, and * we don't trust the pmap module to do it right. */ virtual_space_start = round_page(virtual_space_start); virtual_space_end = trunc_page(virtual_space_end); } /* * Allocate virtual memory for this request. */ addr = virtual_space_start; virtual_space_start += size; /* * Allocate and map physical pages to back new virtual pages. */ for (vaddr = round_page(addr); vaddr < addr + size; vaddr += PAGE_SIZE) { if (!pmap_next_page(&paddr)) panic("pmap_steal_memory"); /* * XXX Logically, these mappings should be wired, * but some pmap modules barf if they are. */ pmap_enter(pmap_kernel(), vaddr, paddr, VM_PROT_READ|VM_PROT_WRITE, FALSE); } return addr; } void pmap_startup(startp, endp) vm_offset_t *startp; vm_offset_t *endp; { unsigned int i, freepages; vm_offset_t paddr; /* * We calculate how many page frames we will have * and then allocate the page structures in one chunk. * The calculation is non-trivial. We want: * * vmpages > (freepages - (vmpages / sizeof(vm_page_t))) * * which, with some algebra, becomes: * * vmpages > (freepages * sizeof(...) / (1 + sizeof(...))) * * The value of vm_page_count need not be exact, but must be * large enough so vm_page_array handles the index range. */ freepages = pmap_free_pages(); /* Fudge slightly to deal with truncation error. */ freepages += 1; /* fudge */ vm_page_count = (PAGE_SIZE * freepages) / (PAGE_SIZE + sizeof(*vm_page_array)); vm_page_array = (vm_page_t) pmap_steal_memory(vm_page_count * sizeof(*vm_page_array)); bzero(vm_page_array, vm_page_count * sizeof(*vm_page_array)); #ifdef DIAGNOSTIC /* * Initialize everyting in case the holes are stepped in, * and set PA to something that will cause a panic... */ for (i = 0; i < vm_page_count; i++) vm_page_array[i].phys_addr = 0xdeadbeef; #endif /* * Initialize the page frames. * Note that some page indices may not be usable * when pmap_free_pages() counts pages in a hole. */ if (!pmap_next_page(&paddr)) panic("pmap_startup: can't get first page"); first_page = pmap_page_index(paddr); i = 0; for (;;) { /* Initialize a page array element. */ VM_PAGE_INIT(&vm_page_array[i], NULL, 0); vm_page_array[i].phys_addr = paddr; vm_page_free(&vm_page_array[i]); /* Are there more physical pages? */ if (!pmap_next_page(&paddr)) break; i = pmap_page_index(paddr) - first_page; /* Don't trust pmap_page_index()... */ if ( #if 0 /* Cannot happen; i is unsigned */ i < 0 || #endif i >= vm_page_count) panic("pmap_startup: bad i=0x%x", i); } *startp = virtual_space_start; *endp = virtual_space_end; } #endif /* MACHINE_NONCONTIG && !MACHINE_PAGES */