/* $OpenBSD: vm_page.c,v 1.8 1997/09/25 07:06:27 niklas Exp $ */ /* $NetBSD: vm_page.c,v 1.31 1997/06/06 23:10:23 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 #ifdef MACHINE_NONCONTIG /* * These variables record the values returned by vm_page_bootstrap, * for debugging purposes. The implementation of pmap_steal_memory * and pmap_startup here also uses them internally. */ vm_offset_t virtual_space_start; vm_offset_t virtual_space_end; #endif /* MACHINE_NONCONTIG */ /* * 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 */ 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; int vm_page_count; #ifndef MACHINE_NONCONTIG long first_page; long last_page; vm_offset_t first_phys_addr; vm_offset_t last_phys_addr; #else u_long first_page; #endif /* MACHINE_NONCONTIG */ vm_size_t page_mask; int page_shift; /* * 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; } #ifdef MACHINE_NONCONTIG /* * 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; { int i; register struct pglist *bucket; 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_offset_t)pmap_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 *) pmap_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); /* * Machine-dependent code allocates the resident page table. * It uses VM_PAGE_INIT to initialize the page frames. * The code also returns to us the virtual space available * to the kernel. We don't trust the pmap module * to get the alignment right. */ pmap_startup(&virtual_space_start, &virtual_space_end); 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); } #else /* MACHINE_NONCONTIG */ /* * 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 */ #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 */ /* * 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_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; /* Keep page from moving out from under pageout daemon */ vm_page_lock_queues(); 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); if (vm_page_queue_free.tqh_first == NULL) { simple_unlock(&vm_page_queue_free_lock); splx(spl); return(NULL); } mem = vm_page_queue_free.tqh_first; 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; 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 (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; } /* * 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]); /* * 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; 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); STAT_DECR(vm_page_alloc_memory_npages); } simple_unlock(&vm_page_queue_free_lock); splx(s); }