/* * Copyright (c) 1991 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_page.c 7.4 (Berkeley) 5/7/91 * $Id: vm_page.c,v 1.112 1998/10/28 13:41:43 dg Exp $ */ /* * 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 #include #include #include #include #include #include static void vm_page_queue_init __P((void)); static vm_page_t vm_page_select_free __P((vm_object_t object, vm_pindex_t pindex, int prefqueue)); static vm_page_t vm_page_select_cache __P((vm_object_t, vm_pindex_t)); /* * Associated with page of user-allocatable memory is a * page structure. */ static struct pglist *vm_page_buckets; /* Array of buckets */ static int vm_page_bucket_count; /* How big is array? */ static int vm_page_hash_mask; /* Mask for hash function */ static volatile int vm_page_bucket_generation; struct pglist vm_page_queue_free[PQ_L2_SIZE] = {0}; struct pglist vm_page_queue_zero[PQ_L2_SIZE] = {0}; struct pglist vm_page_queue_active = {0}; struct pglist vm_page_queue_inactive = {0}; struct pglist vm_page_queue_cache[PQ_L2_SIZE] = {0}; static int no_queue=0; struct vpgqueues vm_page_queues[PQ_COUNT] = {0}; static int pqcnt[PQ_COUNT] = {0}; static void vm_page_queue_init(void) { int i; vm_page_queues[PQ_NONE].pl = NULL; vm_page_queues[PQ_NONE].cnt = &no_queue; for(i=0;i biggestsize) { biggestone = i; biggestsize = size; } ++nblocks; total += size; } start = phys_avail[biggestone]; /* * Initialize the queue headers for the free queue, the active queue * and the inactive queue. */ vm_page_queue_init(); /* * Allocate (and initialize) the 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. */ vm_page_buckets = (struct pglist *) vaddr; bucket = vm_page_buckets; if (vm_page_bucket_count == 0) { vm_page_bucket_count = 1; while (vm_page_bucket_count < atop(total)) vm_page_bucket_count <<= 1; } vm_page_hash_mask = vm_page_bucket_count - 1; /* * Validate these addresses. */ new_start = start + vm_page_bucket_count * sizeof(struct pglist); new_start = round_page(new_start); mapped = round_page(vaddr); vaddr = pmap_map(mapped, start, new_start, VM_PROT_READ | VM_PROT_WRITE); start = new_start; vaddr = round_page(vaddr); bzero((caddr_t) mapped, vaddr - mapped); for (i = 0; i < vm_page_bucket_count; i++) { TAILQ_INIT(bucket); bucket++; } /* * Compute the number of pages of memory that will be available for * use (taking into account the overhead of a page structure per * page). */ first_page = phys_avail[0] / PAGE_SIZE; last_page = phys_avail[(nblocks - 1) * 2 + 1] / PAGE_SIZE; page_range = last_page - (phys_avail[0] / PAGE_SIZE); npages = (total - (page_range * sizeof(struct vm_page)) - (start - phys_avail[biggestone])) / PAGE_SIZE; /* * Initialize the mem entry structures now, and put them in the free * queue. */ vm_page_array = (vm_page_t) vaddr; mapped = vaddr; /* * Validate these addresses. */ new_start = round_page(start + page_range * sizeof(struct vm_page)); mapped = pmap_map(mapped, start, new_start, VM_PROT_READ | VM_PROT_WRITE); start = new_start; first_managed_page = start / PAGE_SIZE; /* * Clear all of the page structures */ bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page)); vm_page_array_size = page_range; cnt.v_page_count = 0; cnt.v_free_count = 0; for (i = 0; phys_avail[i + 1] && npages > 0; i += 2) { if (i == biggestone) pa = ptoa(first_managed_page); else pa = phys_avail[i]; while (pa < phys_avail[i + 1] && npages-- > 0) { ++cnt.v_page_count; ++cnt.v_free_count; m = PHYS_TO_VM_PAGE(pa); m->phys_addr = pa; m->flags = 0; m->pc = (pa >> PAGE_SHIFT) & PQ_L2_MASK; m->queue = m->pc + PQ_FREE; TAILQ_INSERT_TAIL(vm_page_queues[m->queue].pl, m, pageq); ++(*vm_page_queues[m->queue].lcnt); pa += PAGE_SIZE; } } return (mapped); } /* * 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. */ static __inline int vm_page_hash(object, pindex) vm_object_t object; vm_pindex_t pindex; { return ((((uintptr_t) object) >> 5) + (pindex >> 1)) & 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, and must be splhigh. */ void vm_page_insert(m, object, pindex) register vm_page_t m; register vm_object_t object; register vm_pindex_t pindex; { register struct pglist *bucket; if (m->object != NULL) panic("vm_page_insert: already inserted"); /* * Record the object/offset pair in this page */ m->object = object; m->pindex = pindex; /* * Insert it into the object_object/offset hash table */ bucket = &vm_page_buckets[vm_page_hash(object, pindex)]; TAILQ_INSERT_TAIL(bucket, m, hashq); vm_page_bucket_generation++; /* * Now link into the object's list of backed pages. */ TAILQ_INSERT_TAIL(&object->memq, m, listq); m->object->page_hint = m; m->object->generation++; if (m->wire_count) object->wire_count++; if ((m->queue - m->pc) == PQ_CACHE) object->cache_count++; /* * And show that the object has one more resident page. */ object->resident_page_count++; } /* * vm_page_remove: [ internal use only ] * NOTE: used by device pager as well -wfj * * Removes the given mem entry from the object/offset-page * table and the object page list. * * The object and page must be locked, and at splhigh. */ void vm_page_remove(m) register vm_page_t m; { register struct pglist *bucket; vm_object_t object; if (m->object == NULL) return; #if !defined(MAX_PERF) if ((m->flags & PG_BUSY) == 0) { panic("vm_page_remove: page not busy"); } #endif vm_page_flag_clear(m, PG_BUSY); if (m->flags & PG_WANTED) { vm_page_flag_clear(m, PG_WANTED); wakeup(m); } object = m->object; if (object->page_hint == m) object->page_hint = NULL; if (m->wire_count) object->wire_count--; if ((m->queue - m->pc) == PQ_CACHE) object->cache_count--; /* * Remove from the object_object/offset hash table */ bucket = &vm_page_buckets[vm_page_hash(m->object, m->pindex)]; TAILQ_REMOVE(bucket, m, hashq); vm_page_bucket_generation++; /* * Now remove from the object's list of backed pages. */ TAILQ_REMOVE(&object->memq, m, listq); /* * And show that the object has one fewer resident page. */ object->resident_page_count--; object->generation++; m->object = NULL; } /* * 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, pindex) register vm_object_t object; register vm_pindex_t pindex; { register vm_page_t m; register struct pglist *bucket; int generation; /* * Search the hash table for this object/offset pair */ if (object->page_hint && (object->page_hint->pindex == pindex) && (object->page_hint->object == object)) return object->page_hint; retry: generation = vm_page_bucket_generation; bucket = &vm_page_buckets[vm_page_hash(object, pindex)]; for (m = TAILQ_FIRST(bucket); m != NULL; m = TAILQ_NEXT(m,hashq)) { if ((m->object == object) && (m->pindex == pindex)) { if (vm_page_bucket_generation != generation) goto retry; m->object->page_hint = m; return (m); } } if (vm_page_bucket_generation != generation) goto retry; 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(m, new_object, new_pindex) register vm_page_t m; register vm_object_t new_object; vm_pindex_t new_pindex; { int s; s = splvm(); vm_page_remove(m); vm_page_insert(m, new_object, new_pindex); splx(s); } /* * vm_page_unqueue without any wakeup */ void vm_page_unqueue_nowakeup(m) vm_page_t m; { int queue = m->queue; struct vpgqueues *pq; if (queue != PQ_NONE) { pq = &vm_page_queues[queue]; m->queue = PQ_NONE; TAILQ_REMOVE(pq->pl, m, pageq); (*pq->cnt)--; (*pq->lcnt)--; if ((queue - m->pc) == PQ_CACHE) { if (m->object) m->object->cache_count--; } } } /* * vm_page_unqueue must be called at splhigh(); */ void vm_page_unqueue(m) vm_page_t m; { int queue = m->queue; struct vpgqueues *pq; if (queue != PQ_NONE) { m->queue = PQ_NONE; pq = &vm_page_queues[queue]; TAILQ_REMOVE(pq->pl, m, pageq); (*pq->cnt)--; (*pq->lcnt)--; if ((queue - m->pc) == PQ_CACHE) { if ((cnt.v_cache_count + cnt.v_free_count) < (cnt.v_free_reserved + cnt.v_cache_min)) pagedaemon_wakeup(); if (m->object) m->object->cache_count--; } } } /* * Find a page on the specified queue with color optimization. */ vm_page_t vm_page_list_find(basequeue, index) int basequeue, index; { #if PQ_L2_SIZE > 1 int i,j; vm_page_t m; int hindex; struct vpgqueues *pq; pq = &vm_page_queues[basequeue]; m = TAILQ_FIRST(pq[index].pl); if (m) return m; for(j = 0; j < PQ_L1_SIZE; j++) { int ij; for(i = (PQ_L2_SIZE / 2) - PQ_L1_SIZE; (ij = i + j) > 0; i -= PQ_L1_SIZE) { hindex = index + ij; if (hindex >= PQ_L2_SIZE) hindex -= PQ_L2_SIZE; if (m = TAILQ_FIRST(pq[hindex].pl)) return m; hindex = index - ij; if (hindex < 0) hindex += PQ_L2_SIZE; if (m = TAILQ_FIRST(pq[hindex].pl)) return m; } } hindex = index + PQ_L2_SIZE / 2; if (hindex >= PQ_L2_SIZE) hindex -= PQ_L2_SIZE; m = TAILQ_FIRST(pq[hindex].pl); if (m) return m; return NULL; #else return TAILQ_FIRST(vm_page_queues[basequeue].pl); #endif } /* * Find a page on the specified queue with color optimization. */ vm_page_t vm_page_select(object, pindex, basequeue) vm_object_t object; vm_pindex_t pindex; int basequeue; { #if PQ_L2_SIZE > 1 int index; index = (pindex + object->pg_color) & PQ_L2_MASK; return vm_page_list_find(basequeue, index); #else return TAILQ_FIRST(vm_page_queues[basequeue].pl); #endif } /* * Find a page on the cache queue with color optimization. As pages * might be found, but not applicable, they are deactivated. This * keeps us from using potentially busy cached pages. */ vm_page_t vm_page_select_cache(object, pindex) vm_object_t object; vm_pindex_t pindex; { vm_page_t m; while (TRUE) { #if PQ_L2_SIZE > 1 int index; index = (pindex + object->pg_color) & PQ_L2_MASK; m = vm_page_list_find(PQ_CACHE, index); #else m = TAILQ_FIRST(vm_page_queues[PQ_CACHE].pl); #endif if (m && ((m->flags & PG_BUSY) || m->busy || m->hold_count || m->wire_count)) { vm_page_deactivate(m); continue; } return m; } } /* * Find a free or zero page, with specified preference. */ static vm_page_t vm_page_select_free(object, pindex, prefqueue) vm_object_t object; vm_pindex_t pindex; int prefqueue; { #if PQ_L2_SIZE > 1 int i,j; int index, hindex; #endif vm_page_t m, mh; int oqueuediff; struct vpgqueues *pq; if (prefqueue == PQ_ZERO) oqueuediff = PQ_FREE - PQ_ZERO; else oqueuediff = PQ_ZERO - PQ_FREE; if (mh = object->page_hint) { if (mh->pindex == (pindex - 1)) { if ((mh->flags & PG_FICTITIOUS) == 0) { if ((mh < &vm_page_array[cnt.v_page_count-1]) && (mh >= &vm_page_array[0])) { int queue; m = mh + 1; if (VM_PAGE_TO_PHYS(m) == (VM_PAGE_TO_PHYS(mh) + PAGE_SIZE)) { queue = m->queue - m->pc; if (queue == PQ_FREE || queue == PQ_ZERO) { return m; } } } } } } pq = &vm_page_queues[prefqueue]; #if PQ_L2_SIZE > 1 index = (pindex + object->pg_color) & PQ_L2_MASK; if (m = TAILQ_FIRST(pq[index].pl)) return m; if (m = TAILQ_FIRST(pq[index + oqueuediff].pl)) return m; for(j = 0; j < PQ_L1_SIZE; j++) { int ij; for(i = (PQ_L2_SIZE / 2) - PQ_L1_SIZE; (ij = i + j) >= 0; i -= PQ_L1_SIZE) { hindex = index + ij; if (hindex >= PQ_L2_SIZE) hindex -= PQ_L2_SIZE; if (m = TAILQ_FIRST(pq[hindex].pl)) return m; if (m = TAILQ_FIRST(pq[hindex + oqueuediff].pl)) return m; hindex = index - ij; if (hindex < 0) hindex += PQ_L2_SIZE; if (m = TAILQ_FIRST(pq[hindex].pl)) return m; if (m = TAILQ_FIRST(pq[hindex + oqueuediff].pl)) return m; } } hindex = index + PQ_L2_SIZE / 2; if (hindex >= PQ_L2_SIZE) hindex -= PQ_L2_SIZE; if (m = TAILQ_FIRST(pq[hindex].pl)) return m; if (m = TAILQ_FIRST(pq[hindex+oqueuediff].pl)) return m; #else if (m = TAILQ_FIRST(pq[0].pl)) return m; else return TAILQ_FIRST(pq[oqueuediff].pl); #endif return NULL; } /* * vm_page_alloc: * * Allocate and return a memory cell associated * with this VM object/offset pair. * * page_req classes: * VM_ALLOC_NORMAL normal process request * VM_ALLOC_SYSTEM system *really* needs a page * VM_ALLOC_INTERRUPT interrupt time request * VM_ALLOC_ZERO zero page * * Object must be locked. */ vm_page_t vm_page_alloc(object, pindex, page_req) vm_object_t object; vm_pindex_t pindex; int page_req; { register vm_page_t m; struct vpgqueues *pq; vm_object_t oldobject; int queue, qtype; int s; #ifdef DIAGNOSTIC m = vm_page_lookup(object, pindex); if (m) panic("vm_page_alloc: page already allocated"); #endif if ((curproc == pageproc) && (page_req != VM_ALLOC_INTERRUPT)) { page_req = VM_ALLOC_SYSTEM; }; s = splvm(); switch (page_req) { case VM_ALLOC_NORMAL: if (cnt.v_free_count >= cnt.v_free_reserved) { m = vm_page_select_free(object, pindex, PQ_FREE); #if defined(DIAGNOSTIC) if (m == NULL) panic("vm_page_alloc(NORMAL): missing page on free queue\n"); #endif } else { m = vm_page_select_cache(object, pindex); if (m == NULL) { splx(s); #if defined(DIAGNOSTIC) if (cnt.v_cache_count > 0) printf("vm_page_alloc(NORMAL): missing pages on cache queue: %d\n", cnt.v_cache_count); #endif vm_pageout_deficit++; pagedaemon_wakeup(); return (NULL); } } break; case VM_ALLOC_ZERO: if (cnt.v_free_count >= cnt.v_free_reserved) { m = vm_page_select_free(object, pindex, PQ_ZERO); #if defined(DIAGNOSTIC) if (m == NULL) panic("vm_page_alloc(ZERO): missing page on free queue\n"); #endif } else { m = vm_page_select_cache(object, pindex); if (m == NULL) { splx(s); #if defined(DIAGNOSTIC) if (cnt.v_cache_count > 0) printf("vm_page_alloc(ZERO): missing pages on cache queue: %d\n", cnt.v_cache_count); #endif vm_pageout_deficit++; pagedaemon_wakeup(); return (NULL); } } break; case VM_ALLOC_SYSTEM: if ((cnt.v_free_count >= cnt.v_free_reserved) || ((cnt.v_cache_count == 0) && (cnt.v_free_count >= cnt.v_interrupt_free_min))) { m = vm_page_select_free(object, pindex, PQ_FREE); #if defined(DIAGNOSTIC) if (m == NULL) panic("vm_page_alloc(SYSTEM): missing page on free queue\n"); #endif } else { m = vm_page_select_cache(object, pindex); if (m == NULL) { splx(s); #if defined(DIAGNOSTIC) if (cnt.v_cache_count > 0) printf("vm_page_alloc(SYSTEM): missing pages on cache queue: %d\n", cnt.v_cache_count); #endif vm_pageout_deficit++; pagedaemon_wakeup(); return (NULL); } } break; case VM_ALLOC_INTERRUPT: if (cnt.v_free_count > 0) { m = vm_page_select_free(object, pindex, PQ_FREE); #if defined(DIAGNOSTIC) if (m == NULL) panic("vm_page_alloc(INTERRUPT): missing page on free queue\n"); #endif } else { splx(s); vm_pageout_deficit++; pagedaemon_wakeup(); return (NULL); } break; default: m = NULL; #if !defined(MAX_PERF) panic("vm_page_alloc: invalid allocation class"); #endif } queue = m->queue; qtype = queue - m->pc; if (qtype == PQ_ZERO) vm_page_zero_count--; pq = &vm_page_queues[queue]; TAILQ_REMOVE(pq->pl, m, pageq); (*pq->cnt)--; (*pq->lcnt)--; oldobject = NULL; if (qtype == PQ_ZERO) { m->flags = PG_ZERO | PG_BUSY; } else if (qtype == PQ_CACHE) { oldobject = m->object; vm_page_busy(m); vm_page_remove(m); m->flags = PG_BUSY; } else { m->flags = PG_BUSY; } m->wire_count = 0; m->hold_count = 0; m->act_count = 0; m->busy = 0; m->valid = 0; m->dirty = 0; m->queue = PQ_NONE; /* XXX before splx until vm_page_insert is safe */ vm_page_insert(m, object, pindex); /* * Don't wakeup too often - wakeup the pageout daemon when * we would be nearly out of memory. */ if (((cnt.v_free_count + cnt.v_cache_count) < (cnt.v_free_reserved + cnt.v_cache_min)) || (cnt.v_free_count < cnt.v_pageout_free_min)) pagedaemon_wakeup(); if ((qtype == PQ_CACHE) && ((page_req == VM_ALLOC_NORMAL) || (page_req == VM_ALLOC_ZERO)) && oldobject && (oldobject->type == OBJT_VNODE) && ((oldobject->flags & OBJ_DEAD) == 0)) { struct vnode *vp; vp = (struct vnode *) oldobject->handle; if (vp && VSHOULDFREE(vp)) { if ((vp->v_flag & (VFREE|VTBFREE|VDOOMED)) == 0) { TAILQ_INSERT_TAIL(&vnode_tobefree_list, vp, v_freelist); vp->v_flag |= VTBFREE; } } } splx(s); return (m); } void vm_wait() { int s; s = splvm(); if (curproc == pageproc) { vm_pageout_pages_needed = 1; tsleep(&vm_pageout_pages_needed, PSWP, "vmwait", 0); } else { if (!vm_pages_needed) { vm_pages_needed++; wakeup(&vm_pages_needed); } tsleep(&cnt.v_free_count, PVM, "vmwait", 0); } splx(s); } int vm_page_sleep(vm_page_t m, char *msg, char *busy) { int slept = 0; if ((busy && *busy) || (m->flags & PG_BUSY)) { int s; s = splvm(); if ((busy && *busy) || (m->flags & PG_BUSY)) { vm_page_flag_set(m, PG_WANTED); tsleep(m, PVM, msg, 0); slept = 1; } splx(s); } return slept; } /* * 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; { int s; s = splvm(); if (m->queue != PQ_ACTIVE) { if ((m->queue - m->pc) == PQ_CACHE) cnt.v_reactivated++; vm_page_unqueue(m); if (m->wire_count == 0) { m->queue = PQ_ACTIVE; ++(*vm_page_queues[PQ_ACTIVE].lcnt); TAILQ_INSERT_TAIL(&vm_page_queue_active, m, pageq); if (m->act_count < ACT_INIT) m->act_count = ACT_INIT; cnt.v_active_count++; } } else { if (m->act_count < ACT_INIT) m->act_count = ACT_INIT; } splx(s); } /* * helper routine for vm_page_free and vm_page_free_zero */ static int vm_page_freechk_and_unqueue(m) vm_page_t m; { vm_object_t oldobject; oldobject = m->object; #if !defined(MAX_PERF) if (m->busy || ((m->queue - m->pc) == PQ_FREE) || (m->hold_count != 0)) { printf( "vm_page_free: pindex(%lu), busy(%d), PG_BUSY(%d), hold(%d)\n", (u_long)m->pindex, m->busy, (m->flags & PG_BUSY) ? 1 : 0, m->hold_count); if ((m->queue - m->pc) == PQ_FREE) panic("vm_page_free: freeing free page"); else panic("vm_page_free: freeing busy page"); } #endif vm_page_unqueue_nowakeup(m); vm_page_remove(m); if ((m->flags & PG_FICTITIOUS) != 0) { return 0; } m->valid = 0; if (m->wire_count != 0) { #if !defined(MAX_PERF) if (m->wire_count > 1) { panic("vm_page_free: invalid wire count (%d), pindex: 0x%x", m->wire_count, m->pindex); } #endif printf("vm_page_free: freeing wired page\n"); m->wire_count = 0; if (m->object) m->object->wire_count--; cnt.v_wire_count--; } if (oldobject && (oldobject->type == OBJT_VNODE) && ((oldobject->flags & OBJ_DEAD) == 0)) { struct vnode *vp; vp = (struct vnode *) oldobject->handle; if (vp && VSHOULDFREE(vp)) { if ((vp->v_flag & (VTBFREE|VDOOMED|VFREE)) == 0) { TAILQ_INSERT_TAIL(&vnode_tobefree_list, vp, v_freelist); vp->v_flag |= VTBFREE; } } } #ifdef __alpha__ pmap_page_is_free(m); #endif return 1; } /* * helper routine for vm_page_free and vm_page_free_zero */ static __inline void vm_page_free_wakeup() { /* * if pageout daemon needs pages, then tell it that there are * some free. */ if (vm_pageout_pages_needed) { wakeup(&vm_pageout_pages_needed); vm_pageout_pages_needed = 0; } /* * wakeup processes that are waiting on memory if we hit a * high water mark. And wakeup scheduler process if we have * lots of memory. this process will swapin processes. */ if (vm_pages_needed && ((cnt.v_free_count + cnt.v_cache_count) >= cnt.v_free_min)) { wakeup(&cnt.v_free_count); vm_pages_needed = 0; } } /* * 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(m) register vm_page_t m; { int s; struct vpgqueues *pq; s = splvm(); cnt.v_tfree++; if (!vm_page_freechk_and_unqueue(m)) { splx(s); return; } m->queue = PQ_FREE + m->pc; pq = &vm_page_queues[m->queue]; ++(*pq->lcnt); ++(*pq->cnt); /* * If the pageout process is grabbing the page, it is likely * that the page is NOT in the cache. It is more likely that * the page will be partially in the cache if it is being * explicitly freed. */ if (curproc == pageproc) { TAILQ_INSERT_TAIL(pq->pl, m, pageq); } else { TAILQ_INSERT_HEAD(pq->pl, m, pageq); } vm_page_free_wakeup(); splx(s); } void vm_page_free_zero(m) register vm_page_t m; { int s; struct vpgqueues *pq; s = splvm(); cnt.v_tfree++; if (!vm_page_freechk_and_unqueue(m)) { splx(s); return; } m->queue = PQ_ZERO + m->pc; pq = &vm_page_queues[m->queue]; ++(*pq->lcnt); ++(*pq->cnt); TAILQ_INSERT_HEAD(pq->pl, m, pageq); ++vm_page_zero_count; vm_page_free_wakeup(); splx(s); } /* * 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(m) register vm_page_t m; { int s; s = splvm(); if (m->wire_count == 0) { vm_page_unqueue(m); cnt.v_wire_count++; if (m->object) m->object->wire_count++; } m->wire_count++; splx(s); (*vm_page_queues[PQ_NONE].lcnt)++; vm_page_flag_set(m, PG_MAPPED); } /* * 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(m, activate) register vm_page_t m; int activate; { int s; s = splvm(); if (m->wire_count > 0) { m->wire_count--; if (m->wire_count == 0) { if (m->object) m->object->wire_count--; cnt.v_wire_count--; if (activate) { TAILQ_INSERT_TAIL(&vm_page_queue_active, m, pageq); m->queue = PQ_ACTIVE; (*vm_page_queues[PQ_ACTIVE].lcnt)++; cnt.v_active_count++; } else { TAILQ_INSERT_TAIL(&vm_page_queue_inactive, m, pageq); m->queue = PQ_INACTIVE; (*vm_page_queues[PQ_INACTIVE].lcnt)++; cnt.v_inactive_count++; } } } else { #if !defined(MAX_PERF) panic("vm_page_unwire: invalid wire count: %d\n", m->wire_count); #endif } splx(s); } /* * Move the specified page to the inactive queue. */ void vm_page_deactivate(m) register vm_page_t m; { int s; /* * Ignore if already inactive. */ if (m->queue == PQ_INACTIVE) return; s = splvm(); if (m->wire_count == 0) { if ((m->queue - m->pc) == PQ_CACHE) cnt.v_reactivated++; vm_page_unqueue(m); TAILQ_INSERT_TAIL(&vm_page_queue_inactive, m, pageq); m->queue = PQ_INACTIVE; ++(*vm_page_queues[PQ_INACTIVE].lcnt); cnt.v_inactive_count++; } splx(s); } /* * vm_page_cache * * Put the specified page onto the page cache queue (if appropriate). */ void vm_page_cache(m) register vm_page_t m; { int s; #if !defined(MAX_PERF) if ((m->flags & PG_BUSY) || m->busy || m->wire_count) { printf("vm_page_cache: attempting to cache busy page\n"); return; } #endif if ((m->queue - m->pc) == PQ_CACHE) return; vm_page_protect(m, VM_PROT_NONE); #if !defined(MAX_PERF) if (m->dirty != 0) { panic("vm_page_cache: caching a dirty page, pindex: %d", m->pindex); } #endif s = splvm(); vm_page_unqueue_nowakeup(m); m->queue = PQ_CACHE + m->pc; (*vm_page_queues[m->queue].lcnt)++; TAILQ_INSERT_TAIL(vm_page_queues[m->queue].pl, m, pageq); cnt.v_cache_count++; m->object->cache_count++; vm_page_free_wakeup(); splx(s); } /* * Grab a page, waiting until we are waken up due to the page * changing state. We keep on waiting, if the page continues * to be in the object. If the page doesn't exist, allocate it. */ vm_page_t vm_page_grab(object, pindex, allocflags) vm_object_t object; vm_pindex_t pindex; int allocflags; { vm_page_t m; int s, generation; retrylookup: if ((m = vm_page_lookup(object, pindex)) != NULL) { if (m->busy || (m->flags & PG_BUSY)) { generation = object->generation; s = splvm(); while ((object->generation == generation) && (m->busy || (m->flags & PG_BUSY))) { vm_page_flag_set(m, PG_WANTED | PG_REFERENCED); tsleep(m, PVM, "pgrbwt", 0); if ((allocflags & VM_ALLOC_RETRY) == 0) { splx(s); return NULL; } } splx(s); goto retrylookup; } else { vm_page_busy(m); return m; } } m = vm_page_alloc(object, pindex, allocflags & ~VM_ALLOC_RETRY); if (m == NULL) { VM_WAIT; if ((allocflags & VM_ALLOC_RETRY) == 0) return NULL; goto retrylookup; } return m; } /* * mapping function for valid bits or for dirty bits in * a page */ __inline int vm_page_bits(int base, int size) { u_short chunk; if ((base == 0) && (size >= PAGE_SIZE)) return VM_PAGE_BITS_ALL; size = (size + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); base &= PAGE_MASK; if (size > PAGE_SIZE - base) { size = PAGE_SIZE - base; } base = base / DEV_BSIZE; chunk = vm_page_dev_bsize_chunks[size / DEV_BSIZE]; return (chunk << base) & VM_PAGE_BITS_ALL; } /* * set a page valid and clean */ void vm_page_set_validclean(m, base, size) vm_page_t m; int base; int size; { int pagebits = vm_page_bits(base, size); m->valid |= pagebits; m->dirty &= ~pagebits; if( base == 0 && size == PAGE_SIZE) pmap_clear_modify(VM_PAGE_TO_PHYS(m)); } /* * set a page (partially) invalid */ void vm_page_set_invalid(m, base, size) vm_page_t m; int base; int size; { int bits; m->valid &= ~(bits = vm_page_bits(base, size)); if (m->valid == 0) m->dirty &= ~bits; m->object->generation++; } /* * is (partial) page valid? */ int vm_page_is_valid(m, base, size) vm_page_t m; int base; int size; { int bits = vm_page_bits(base, size); if (m->valid && ((m->valid & bits) == bits)) return 1; else return 0; } void vm_page_test_dirty(m) vm_page_t m; { if ((m->dirty != VM_PAGE_BITS_ALL) && pmap_is_modified(VM_PAGE_TO_PHYS(m))) { m->dirty = VM_PAGE_BITS_ALL; } } /* * This interface is for merging with malloc() someday. * Even if we never implement compaction so that contiguous allocation * works after initialization time, malloc()'s data structures are good * for statistics and for allocations of less than a page. */ void * contigmalloc1(size, type, flags, low, high, alignment, boundary, map) unsigned long size; /* should be size_t here and for malloc() */ struct malloc_type *type; int flags; unsigned long low; unsigned long high; unsigned long alignment; unsigned long boundary; vm_map_t map; { int i, s, start; vm_offset_t addr, phys, tmp_addr; int pass; vm_page_t pga = vm_page_array; size = round_page(size); #if !defined(MAX_PERF) if (size == 0) panic("contigmalloc1: size must not be 0"); if ((alignment & (alignment - 1)) != 0) panic("contigmalloc1: alignment must be a power of 2"); if ((boundary & (boundary - 1)) != 0) panic("contigmalloc1: boundary must be a power of 2"); #endif start = 0; for (pass = 0; pass <= 1; pass++) { s = splvm(); again: /* * Find first page in array that is free, within range, aligned, and * such that the boundary won't be crossed. */ for (i = start; i < cnt.v_page_count; i++) { int pqtype; phys = VM_PAGE_TO_PHYS(&pga[i]); pqtype = pga[i].queue - pga[i].pc; if (((pqtype == PQ_ZERO) || (pqtype == PQ_FREE) || (pqtype == PQ_CACHE)) && (phys >= low) && (phys < high) && ((phys & (alignment - 1)) == 0) && (((phys ^ (phys + size - 1)) & ~(boundary - 1)) == 0)) break; } /* * If the above failed or we will exceed the upper bound, fail. */ if ((i == cnt.v_page_count) || ((VM_PAGE_TO_PHYS(&pga[i]) + size) > high)) { vm_page_t m, next; again1: for (m = TAILQ_FIRST(&vm_page_queue_inactive); m != NULL; m = next) { if (m->queue != PQ_INACTIVE) { break; } next = TAILQ_NEXT(m, pageq); if (vm_page_sleep(m, "vpctw0", &m->busy)) goto again1; vm_page_test_dirty(m); if (m->dirty) { if (m->object->type == OBJT_VNODE) { vn_lock(m->object->handle, LK_EXCLUSIVE | LK_RETRY, curproc); vm_object_page_clean(m->object, 0, 0, OBJPC_SYNC); VOP_UNLOCK(m->object->handle, 0, curproc); goto again1; } else if (m->object->type == OBJT_SWAP || m->object->type == OBJT_DEFAULT) { vm_pageout_flush(&m, 1, 0); goto again1; } } if ((m->dirty == 0) && (m->busy == 0) && (m->hold_count == 0)) vm_page_cache(m); } for (m = TAILQ_FIRST(&vm_page_queue_active); m != NULL; m = next) { if (m->queue != PQ_ACTIVE) { break; } next = TAILQ_NEXT(m, pageq); if (vm_page_sleep(m, "vpctw1", &m->busy)) goto again1; vm_page_test_dirty(m); if (m->dirty) { if (m->object->type == OBJT_VNODE) { vn_lock(m->object->handle, LK_EXCLUSIVE | LK_RETRY, curproc); vm_object_page_clean(m->object, 0, 0, OBJPC_SYNC); VOP_UNLOCK(m->object->handle, 0, curproc); goto again1; } else if (m->object->type == OBJT_SWAP || m->object->type == OBJT_DEFAULT) { vm_pageout_flush(&m, 1, 0); goto again1; } } if ((m->dirty == 0) && (m->busy == 0) && (m->hold_count == 0)) vm_page_cache(m); } splx(s); continue; } start = i; /* * Check successive pages for contiguous and free. */ for (i = start + 1; i < (start + size / PAGE_SIZE); i++) { int pqtype; pqtype = pga[i].queue - pga[i].pc; if ((VM_PAGE_TO_PHYS(&pga[i]) != (VM_PAGE_TO_PHYS(&pga[i - 1]) + PAGE_SIZE)) || ((pqtype != PQ_ZERO) && (pqtype != PQ_FREE) && (pqtype != PQ_CACHE))) { start++; goto again; } } for (i = start; i < (start + size / PAGE_SIZE); i++) { int pqtype; vm_page_t m = &pga[i]; pqtype = m->queue - m->pc; if (pqtype == PQ_CACHE) { vm_page_busy(m); vm_page_free(m); } TAILQ_REMOVE(vm_page_queues[m->queue].pl, m, pageq); (*vm_page_queues[m->queue].lcnt)--; cnt.v_free_count--; m->valid = VM_PAGE_BITS_ALL; m->flags = 0; m->dirty = 0; m->wire_count = 0; m->busy = 0; m->queue = PQ_NONE; m->object = NULL; vm_page_wire(m); } /* * We've found a contiguous chunk that meets are requirements. * Allocate kernel VM, unfree and assign the physical pages to it and * return kernel VM pointer. */ tmp_addr = addr = kmem_alloc_pageable(map, size); if (addr == 0) { /* * XXX We almost never run out of kernel virtual * space, so we don't make the allocated memory * above available. */ splx(s); return (NULL); } for (i = start; i < (start + size / PAGE_SIZE); i++) { vm_page_t m = &pga[i]; vm_page_insert(m, kernel_object, OFF_TO_IDX(tmp_addr - VM_MIN_KERNEL_ADDRESS)); pmap_kenter(tmp_addr, VM_PAGE_TO_PHYS(m)); tmp_addr += PAGE_SIZE; } splx(s); return ((void *)addr); } return NULL; } void * contigmalloc(size, type, flags, low, high, alignment, boundary) unsigned long size; /* should be size_t here and for malloc() */ struct malloc_type *type; int flags; unsigned long low; unsigned long high; unsigned long alignment; unsigned long boundary; { return contigmalloc1(size, type, flags, low, high, alignment, boundary, kernel_map); } vm_offset_t vm_page_alloc_contig(size, low, high, alignment) vm_offset_t size; vm_offset_t low; vm_offset_t high; vm_offset_t alignment; { return ((vm_offset_t)contigmalloc1(size, M_DEVBUF, M_NOWAIT, low, high, alignment, 0ul, kernel_map)); } #include "opt_ddb.h" #ifdef DDB #include #include DB_SHOW_COMMAND(page, vm_page_print_page_info) { db_printf("cnt.v_free_count: %d\n", cnt.v_free_count); db_printf("cnt.v_cache_count: %d\n", cnt.v_cache_count); db_printf("cnt.v_inactive_count: %d\n", cnt.v_inactive_count); db_printf("cnt.v_active_count: %d\n", cnt.v_active_count); db_printf("cnt.v_wire_count: %d\n", cnt.v_wire_count); db_printf("cnt.v_free_reserved: %d\n", cnt.v_free_reserved); db_printf("cnt.v_free_min: %d\n", cnt.v_free_min); db_printf("cnt.v_free_target: %d\n", cnt.v_free_target); db_printf("cnt.v_cache_min: %d\n", cnt.v_cache_min); db_printf("cnt.v_inactive_target: %d\n", cnt.v_inactive_target); } DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) { int i; db_printf("PQ_FREE:"); for(i=0;i