160727d8bSWarner Losh /*- 2df8bae1dSRodney W. Grimes * Copyright (c) 1991, 1993 3df8bae1dSRodney W. Grimes * The Regents of the University of California. All rights reserved. 4df8bae1dSRodney W. Grimes * 5df8bae1dSRodney W. Grimes * This code is derived from software contributed to Berkeley by 6df8bae1dSRodney W. Grimes * The Mach Operating System project at Carnegie-Mellon University. 7df8bae1dSRodney W. Grimes * 8df8bae1dSRodney W. Grimes * Redistribution and use in source and binary forms, with or without 9df8bae1dSRodney W. Grimes * modification, are permitted provided that the following conditions 10df8bae1dSRodney W. Grimes * are met: 11df8bae1dSRodney W. Grimes * 1. Redistributions of source code must retain the above copyright 12df8bae1dSRodney W. Grimes * notice, this list of conditions and the following disclaimer. 13df8bae1dSRodney W. Grimes * 2. Redistributions in binary form must reproduce the above copyright 14df8bae1dSRodney W. Grimes * notice, this list of conditions and the following disclaimer in the 15df8bae1dSRodney W. Grimes * documentation and/or other materials provided with the distribution. 16df8bae1dSRodney W. Grimes * 4. Neither the name of the University nor the names of its contributors 17df8bae1dSRodney W. Grimes * may be used to endorse or promote products derived from this software 18df8bae1dSRodney W. Grimes * without specific prior written permission. 19df8bae1dSRodney W. Grimes * 20df8bae1dSRodney W. Grimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21df8bae1dSRodney W. Grimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22df8bae1dSRodney W. Grimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23df8bae1dSRodney W. Grimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24df8bae1dSRodney W. Grimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25df8bae1dSRodney W. Grimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26df8bae1dSRodney W. Grimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27df8bae1dSRodney W. Grimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28df8bae1dSRodney W. Grimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29df8bae1dSRodney W. Grimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30df8bae1dSRodney W. Grimes * SUCH DAMAGE. 31df8bae1dSRodney W. Grimes * 323c4dd356SDavid Greenman * from: @(#)vm_kern.c 8.3 (Berkeley) 1/12/94 33df8bae1dSRodney W. Grimes * 34df8bae1dSRodney W. Grimes * 35df8bae1dSRodney W. Grimes * Copyright (c) 1987, 1990 Carnegie-Mellon University. 36df8bae1dSRodney W. Grimes * All rights reserved. 37df8bae1dSRodney W. Grimes * 38df8bae1dSRodney W. Grimes * Authors: Avadis Tevanian, Jr., Michael Wayne Young 39df8bae1dSRodney W. Grimes * 40df8bae1dSRodney W. Grimes * Permission to use, copy, modify and distribute this software and 41df8bae1dSRodney W. Grimes * its documentation is hereby granted, provided that both the copyright 42df8bae1dSRodney W. Grimes * notice and this permission notice appear in all copies of the 43df8bae1dSRodney W. Grimes * software, derivative works or modified versions, and any portions 44df8bae1dSRodney W. Grimes * thereof, and that both notices appear in supporting documentation. 45df8bae1dSRodney W. Grimes * 46df8bae1dSRodney W. Grimes * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 47df8bae1dSRodney W. Grimes * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 48df8bae1dSRodney W. Grimes * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 49df8bae1dSRodney W. Grimes * 50df8bae1dSRodney W. Grimes * Carnegie Mellon requests users of this software to return to 51df8bae1dSRodney W. Grimes * 52df8bae1dSRodney W. Grimes * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 53df8bae1dSRodney W. Grimes * School of Computer Science 54df8bae1dSRodney W. Grimes * Carnegie Mellon University 55df8bae1dSRodney W. Grimes * Pittsburgh PA 15213-3890 56df8bae1dSRodney W. Grimes * 57df8bae1dSRodney W. Grimes * any improvements or extensions that they make and grant Carnegie the 58df8bae1dSRodney W. Grimes * rights to redistribute these changes. 59df8bae1dSRodney W. Grimes */ 60df8bae1dSRodney W. Grimes 61df8bae1dSRodney W. Grimes /* 62df8bae1dSRodney W. Grimes * Kernel memory management. 63df8bae1dSRodney W. Grimes */ 64df8bae1dSRodney W. Grimes 65874651b1SDavid E. O'Brien #include <sys/cdefs.h> 66874651b1SDavid E. O'Brien __FBSDID("$FreeBSD$"); 67874651b1SDavid E. O'Brien 68df8bae1dSRodney W. Grimes #include <sys/param.h> 69df8bae1dSRodney W. Grimes #include <sys/systm.h> 7060363fb9SLuigi Rizzo #include <sys/kernel.h> /* for ticks and hz */ 710f2c2ce0SPawel Jakub Dawidek #include <sys/eventhandler.h> 72fb919e4dSMark Murray #include <sys/lock.h> 73fb919e4dSMark Murray #include <sys/mutex.h> 74f23b4c91SGarrett Wollman #include <sys/proc.h> 75a1f6d91cSDavid Greenman #include <sys/malloc.h> 7686f08737SRobert Watson #include <sys/sysctl.h> 77df8bae1dSRodney W. Grimes 78df8bae1dSRodney W. Grimes #include <vm/vm.h> 79efeaf95aSDavid Greenman #include <vm/vm_param.h> 80efeaf95aSDavid Greenman #include <vm/pmap.h> 81efeaf95aSDavid Greenman #include <vm/vm_map.h> 82efeaf95aSDavid Greenman #include <vm/vm_object.h> 83df8bae1dSRodney W. Grimes #include <vm/vm_page.h> 84df8bae1dSRodney W. Grimes #include <vm/vm_pageout.h> 859b4288a3SBruce Evans #include <vm/vm_extern.h> 860f2c2ce0SPawel Jakub Dawidek #include <vm/uma.h> 87df8bae1dSRodney W. Grimes 885b0a7408SJohn Dyson vm_map_t kernel_map=0; 895b0a7408SJohn Dyson vm_map_t kmem_map=0; 905b0a7408SJohn Dyson vm_map_t exec_map=0; 91cebde069SMike Silbersack vm_map_t pipe_map; 925b0a7408SJohn Dyson vm_map_t buffer_map=0; 93f23b4c91SGarrett Wollman 94df8bae1dSRodney W. Grimes /* 95a839bdc8SDmitrij Tejblum * kmem_alloc_nofault: 96a839bdc8SDmitrij Tejblum * 97b77c2bcdSAlan Cox * Allocate a virtual address range with no underlying object and 98b77c2bcdSAlan Cox * no initial mapping to physical memory. Any mapping from this 99b77c2bcdSAlan Cox * range to physical memory must be explicitly created prior to 100b77c2bcdSAlan Cox * its use, typically with pmap_qenter(). Any attempt to create 101b77c2bcdSAlan Cox * a mapping on demand through vm_fault() will result in a panic. 102a839bdc8SDmitrij Tejblum */ 103a839bdc8SDmitrij Tejblum vm_offset_t 104a839bdc8SDmitrij Tejblum kmem_alloc_nofault(map, size) 105a839bdc8SDmitrij Tejblum vm_map_t map; 106030f2369SAlfred Perlstein vm_size_t size; 107a839bdc8SDmitrij Tejblum { 108a839bdc8SDmitrij Tejblum vm_offset_t addr; 109030f2369SAlfred Perlstein int result; 110a839bdc8SDmitrij Tejblum 111a839bdc8SDmitrij Tejblum size = round_page(size); 112a839bdc8SDmitrij Tejblum addr = vm_map_min(map); 1133202ed75SAlan Cox result = vm_map_find(map, NULL, 0, &addr, size, VMFS_ANY_SPACE, 1143202ed75SAlan Cox VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 115a839bdc8SDmitrij Tejblum if (result != KERN_SUCCESS) { 116a839bdc8SDmitrij Tejblum return (0); 117a839bdc8SDmitrij Tejblum } 118a839bdc8SDmitrij Tejblum return (addr); 119a839bdc8SDmitrij Tejblum } 120a839bdc8SDmitrij Tejblum 121a839bdc8SDmitrij Tejblum /* 122*ca596a25SJuli Mallett * kmem_alloc_nofault_space: 123*ca596a25SJuli Mallett * 124*ca596a25SJuli Mallett * Allocate a virtual address range with no underlying object and 125*ca596a25SJuli Mallett * no initial mapping to physical memory within the specified 126*ca596a25SJuli Mallett * address space. Any mapping from this range to physical memory 127*ca596a25SJuli Mallett * must be explicitly created prior to its use, typically with 128*ca596a25SJuli Mallett * pmap_qenter(). Any attempt to create a mapping on demand 129*ca596a25SJuli Mallett * through vm_fault() will result in a panic. 130*ca596a25SJuli Mallett */ 131*ca596a25SJuli Mallett vm_offset_t 132*ca596a25SJuli Mallett kmem_alloc_nofault_space(map, size, find_space) 133*ca596a25SJuli Mallett vm_map_t map; 134*ca596a25SJuli Mallett vm_size_t size; 135*ca596a25SJuli Mallett int find_space; 136*ca596a25SJuli Mallett { 137*ca596a25SJuli Mallett vm_offset_t addr; 138*ca596a25SJuli Mallett int result; 139*ca596a25SJuli Mallett 140*ca596a25SJuli Mallett size = round_page(size); 141*ca596a25SJuli Mallett addr = vm_map_min(map); 142*ca596a25SJuli Mallett result = vm_map_find(map, NULL, 0, &addr, size, find_space, 143*ca596a25SJuli Mallett VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 144*ca596a25SJuli Mallett if (result != KERN_SUCCESS) { 145*ca596a25SJuli Mallett return (0); 146*ca596a25SJuli Mallett } 147*ca596a25SJuli Mallett return (addr); 148*ca596a25SJuli Mallett } 149*ca596a25SJuli Mallett 150*ca596a25SJuli Mallett /* 151df8bae1dSRodney W. Grimes * Allocate wired-down memory in the kernel's address map 152df8bae1dSRodney W. Grimes * or a submap. 153df8bae1dSRodney W. Grimes */ 1540d94caffSDavid Greenman vm_offset_t 1550d94caffSDavid Greenman kmem_alloc(map, size) 156030f2369SAlfred Perlstein vm_map_t map; 157030f2369SAlfred Perlstein vm_size_t size; 158df8bae1dSRodney W. Grimes { 159df8bae1dSRodney W. Grimes vm_offset_t addr; 160030f2369SAlfred Perlstein vm_offset_t offset; 161df8bae1dSRodney W. Grimes vm_offset_t i; 162df8bae1dSRodney W. Grimes 163df8bae1dSRodney W. Grimes size = round_page(size); 164df8bae1dSRodney W. Grimes 165df8bae1dSRodney W. Grimes /* 1660d94caffSDavid Greenman * Use the kernel object for wired-down kernel pages. Assume that no 1670d94caffSDavid Greenman * region of the kernel object is referenced more than once. 168df8bae1dSRodney W. Grimes */ 169df8bae1dSRodney W. Grimes 170df8bae1dSRodney W. Grimes /* 1710d94caffSDavid Greenman * Locate sufficient space in the map. This will give us the final 1720d94caffSDavid Greenman * virtual address for the new memory, and thus will tell us the 1730d94caffSDavid Greenman * offset within the kernel map. 174df8bae1dSRodney W. Grimes */ 175df8bae1dSRodney W. Grimes vm_map_lock(map); 176e47ed70bSJohn Dyson if (vm_map_findspace(map, vm_map_min(map), size, &addr)) { 177df8bae1dSRodney W. Grimes vm_map_unlock(map); 178df8bae1dSRodney W. Grimes return (0); 179df8bae1dSRodney W. Grimes } 180df8bae1dSRodney W. Grimes offset = addr - VM_MIN_KERNEL_ADDRESS; 181df8bae1dSRodney W. Grimes vm_object_reference(kernel_object); 182bd7e5f99SJohn Dyson vm_map_insert(map, kernel_object, offset, addr, addr + size, 183bd7e5f99SJohn Dyson VM_PROT_ALL, VM_PROT_ALL, 0); 184df8bae1dSRodney W. Grimes vm_map_unlock(map); 185df8bae1dSRodney W. Grimes 186df8bae1dSRodney W. Grimes /* 1870d94caffSDavid Greenman * Guarantee that there are pages already in this object before 1888f101a2fSJonathan Mini * calling vm_map_wire. This is to prevent the following 1890d94caffSDavid Greenman * scenario: 190df8bae1dSRodney W. Grimes * 1910d94caffSDavid Greenman * 1) Threads have swapped out, so that there is a pager for the 1920d94caffSDavid Greenman * kernel_object. 2) The kmsg zone is empty, and so we are 1938f101a2fSJonathan Mini * kmem_allocing a new page for it. 3) vm_map_wire calls vm_fault; 1940d94caffSDavid Greenman * there is no page, but there is a pager, so we call 1950d94caffSDavid Greenman * pager_data_request. But the kmsg zone is empty, so we must 1960d94caffSDavid Greenman * kmem_alloc. 4) goto 1 5) Even if the kmsg zone is not empty: when 1970d94caffSDavid Greenman * we get the data back from the pager, it will be (very stale) 1980d94caffSDavid Greenman * non-zero data. kmem_alloc is defined to return zero-filled memory. 199df8bae1dSRodney W. Grimes * 2000d94caffSDavid Greenman * We're intentionally not activating the pages we allocate to prevent a 2018f101a2fSJonathan Mini * race with page-out. vm_map_wire will wire the pages. 202df8bae1dSRodney W. Grimes */ 20349c06616SAlan Cox VM_OBJECT_LOCK(kernel_object); 204df8bae1dSRodney W. Grimes for (i = 0; i < size; i += PAGE_SIZE) { 205df8bae1dSRodney W. Grimes vm_page_t mem; 206df8bae1dSRodney W. Grimes 20795461b45SJohn Dyson mem = vm_page_grab(kernel_object, OFF_TO_IDX(offset + i), 208ddf4bb37SAlan Cox VM_ALLOC_NOBUSY | VM_ALLOC_ZERO | VM_ALLOC_RETRY); 2097fb0c17eSDavid Greenman mem->valid = VM_PAGE_BITS_ALL; 2109f5c801bSAlan Cox KASSERT((mem->flags & PG_UNMANAGED) != 0, 2119f5c801bSAlan Cox ("kmem_alloc: page %p is managed", mem)); 212df8bae1dSRodney W. Grimes } 21349c06616SAlan Cox VM_OBJECT_UNLOCK(kernel_object); 214df8bae1dSRodney W. Grimes 215df8bae1dSRodney W. Grimes /* 216df8bae1dSRodney W. Grimes * And finally, mark the data as non-pageable. 217df8bae1dSRodney W. Grimes */ 218abd498aaSBruce M Simpson (void) vm_map_wire(map, addr, addr + size, 219abd498aaSBruce M Simpson VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES); 220df8bae1dSRodney W. Grimes 221df8bae1dSRodney W. Grimes return (addr); 222df8bae1dSRodney W. Grimes } 223df8bae1dSRodney W. Grimes 224df8bae1dSRodney W. Grimes /* 225df8bae1dSRodney W. Grimes * kmem_free: 226df8bae1dSRodney W. Grimes * 227df8bae1dSRodney W. Grimes * Release a region of kernel virtual memory allocated 228df8bae1dSRodney W. Grimes * with kmem_alloc, and return the physical pages 229df8bae1dSRodney W. Grimes * associated with that region. 2301c7c3c6aSMatthew Dillon * 2311c7c3c6aSMatthew Dillon * This routine may not block on kernel maps. 232df8bae1dSRodney W. Grimes */ 2330d94caffSDavid Greenman void 2340d94caffSDavid Greenman kmem_free(map, addr, size) 235df8bae1dSRodney W. Grimes vm_map_t map; 236030f2369SAlfred Perlstein vm_offset_t addr; 237df8bae1dSRodney W. Grimes vm_size_t size; 238df8bae1dSRodney W. Grimes { 23923955314SAlfred Perlstein 240df8bae1dSRodney W. Grimes (void) vm_map_remove(map, trunc_page(addr), round_page(addr + size)); 241df8bae1dSRodney W. Grimes } 242df8bae1dSRodney W. Grimes 243df8bae1dSRodney W. Grimes /* 244df8bae1dSRodney W. Grimes * kmem_suballoc: 245df8bae1dSRodney W. Grimes * 246df8bae1dSRodney W. Grimes * Allocates a map to manage a subrange 247df8bae1dSRodney W. Grimes * of the kernel virtual address space. 248df8bae1dSRodney W. Grimes * 249df8bae1dSRodney W. Grimes * Arguments are as follows: 250df8bae1dSRodney W. Grimes * 251df8bae1dSRodney W. Grimes * parent Map to take range from 252df8bae1dSRodney W. Grimes * min, max Returned endpoints of map 253030f2369SAlfred Perlstein * size Size of range to find 2543202ed75SAlan Cox * superpage_align Request that min is superpage aligned 255df8bae1dSRodney W. Grimes */ 2560d94caffSDavid Greenman vm_map_t 2573202ed75SAlan Cox kmem_suballoc(vm_map_t parent, vm_offset_t *min, vm_offset_t *max, 2583202ed75SAlan Cox vm_size_t size, boolean_t superpage_align) 259df8bae1dSRodney W. Grimes { 2606e4f51d1SAlfred Perlstein int ret; 261df8bae1dSRodney W. Grimes vm_map_t result; 26223955314SAlfred Perlstein 263df8bae1dSRodney W. Grimes size = round_page(size); 264df8bae1dSRodney W. Grimes 2652bc24aa9SAlan Cox *min = vm_map_min(parent); 2663202ed75SAlan Cox ret = vm_map_find(parent, NULL, 0, min, size, superpage_align ? 2673364c323SKonstantin Belousov VMFS_ALIGNED_SPACE : VMFS_ANY_SPACE, VM_PROT_ALL, VM_PROT_ALL, 2683364c323SKonstantin Belousov MAP_ACC_NO_CHARGE); 26924dedba9SAlan Cox if (ret != KERN_SUCCESS) 27024dedba9SAlan Cox panic("kmem_suballoc: bad status return of %d", ret); 271df8bae1dSRodney W. Grimes *max = *min + size; 2722d8acc0fSJohn Dyson result = vm_map_create(vm_map_pmap(parent), *min, *max); 273df8bae1dSRodney W. Grimes if (result == NULL) 274df8bae1dSRodney W. Grimes panic("kmem_suballoc: cannot create submap"); 2756e4f51d1SAlfred Perlstein if (vm_map_submap(parent, *min, *max, result) != KERN_SUCCESS) 276df8bae1dSRodney W. Grimes panic("kmem_suballoc: unable to change range to submap"); 277df8bae1dSRodney W. Grimes return (result); 278df8bae1dSRodney W. Grimes } 279df8bae1dSRodney W. Grimes 280df8bae1dSRodney W. Grimes /* 2811c7c3c6aSMatthew Dillon * kmem_malloc: 2821c7c3c6aSMatthew Dillon * 283df8bae1dSRodney W. Grimes * Allocate wired-down memory in the kernel's address map for the higher 284df8bae1dSRodney W. Grimes * level kernel memory allocator (kern/kern_malloc.c). We cannot use 285df8bae1dSRodney W. Grimes * kmem_alloc() because we may need to allocate memory at interrupt 286df8bae1dSRodney W. Grimes * level where we cannot block (canwait == FALSE). 287df8bae1dSRodney W. Grimes * 288df8bae1dSRodney W. Grimes * This routine has its own private kernel submap (kmem_map) and object 289df8bae1dSRodney W. Grimes * (kmem_object). This, combined with the fact that only malloc uses 290df8bae1dSRodney W. Grimes * this routine, ensures that we will never block in map or object waits. 291df8bae1dSRodney W. Grimes * 292df8bae1dSRodney W. Grimes * We don't worry about expanding the map (adding entries) since entries 293df8bae1dSRodney W. Grimes * for wired maps are statically allocated. 2941c7c3c6aSMatthew Dillon * 29508442f8aSBosko Milekic * `map' is ONLY allowed to be kmem_map or one of the mbuf submaps to 29608442f8aSBosko Milekic * which we never free. 297df8bae1dSRodney W. Grimes */ 298df8bae1dSRodney W. Grimes vm_offset_t 2991c7c3c6aSMatthew Dillon kmem_malloc(map, size, flags) 300030f2369SAlfred Perlstein vm_map_t map; 301030f2369SAlfred Perlstein vm_size_t size; 3021c7c3c6aSMatthew Dillon int flags; 303df8bae1dSRodney W. Grimes { 304030f2369SAlfred Perlstein vm_offset_t offset, i; 305655c3490SKonstantin Belousov vm_map_entry_t entry; 306df8bae1dSRodney W. Grimes vm_offset_t addr; 307df8bae1dSRodney W. Grimes vm_page_t m; 3081e081f88SJeff Roberson int pflags; 309df8bae1dSRodney W. Grimes 310df8bae1dSRodney W. Grimes size = round_page(size); 311df8bae1dSRodney W. Grimes addr = vm_map_min(map); 312df8bae1dSRodney W. Grimes 313df8bae1dSRodney W. Grimes /* 3140d94caffSDavid Greenman * Locate sufficient space in the map. This will give us the final 3150d94caffSDavid Greenman * virtual address for the new memory, and thus will tell us the 3160d94caffSDavid Greenman * offset within the kernel map. 317df8bae1dSRodney W. Grimes */ 318df8bae1dSRodney W. Grimes vm_map_lock(map); 319e47ed70bSJohn Dyson if (vm_map_findspace(map, vm_map_min(map), size, &addr)) { 320df8bae1dSRodney W. Grimes vm_map_unlock(map); 3210f2c2ce0SPawel Jakub Dawidek if ((flags & M_NOWAIT) == 0) { 32279c2840dSPawel Jakub Dawidek for (i = 0; i < 8; i++) { 3230f2c2ce0SPawel Jakub Dawidek EVENTHANDLER_INVOKE(vm_lowmem, 0); 3240f2c2ce0SPawel Jakub Dawidek uma_reclaim(); 3250f2c2ce0SPawel Jakub Dawidek vm_map_lock(map); 32679c2840dSPawel Jakub Dawidek if (vm_map_findspace(map, vm_map_min(map), 32779c2840dSPawel Jakub Dawidek size, &addr) == 0) { 32879c2840dSPawel Jakub Dawidek break; 32979c2840dSPawel Jakub Dawidek } 3300f2c2ce0SPawel Jakub Dawidek vm_map_unlock(map); 33179c2840dSPawel Jakub Dawidek tsleep(&i, 0, "nokva", (hz / 4) * (i + 1)); 33279c2840dSPawel Jakub Dawidek } 33379c2840dSPawel Jakub Dawidek if (i == 8) { 3343efc015bSPeter Wemm panic("kmem_malloc(%ld): kmem_map too small: %ld total allocated", 3353efc015bSPeter Wemm (long)size, (long)map->size); 3360f2c2ce0SPawel Jakub Dawidek } 3370f2c2ce0SPawel Jakub Dawidek } else { 338f31c239dSAlan Cox return (0); 339df8bae1dSRodney W. Grimes } 3400f2c2ce0SPawel Jakub Dawidek } 3410891ef4cSJohn Dyson offset = addr - VM_MIN_KERNEL_ADDRESS; 342df8bae1dSRodney W. Grimes vm_object_reference(kmem_object); 343bd7e5f99SJohn Dyson vm_map_insert(map, kmem_object, offset, addr, addr + size, 344bd7e5f99SJohn Dyson VM_PROT_ALL, VM_PROT_ALL, 0); 345df8bae1dSRodney W. Grimes 34695f24639SJeff Roberson if ((flags & (M_NOWAIT|M_USE_RESERVE)) == M_NOWAIT) 347a623fedeSAlan Cox pflags = VM_ALLOC_INTERRUPT | VM_ALLOC_WIRED; 34895f24639SJeff Roberson else 349a623fedeSAlan Cox pflags = VM_ALLOC_SYSTEM | VM_ALLOC_WIRED; 35095f24639SJeff Roberson 35195f24639SJeff Roberson if (flags & M_ZERO) 35295f24639SJeff Roberson pflags |= VM_ALLOC_ZERO; 35395f24639SJeff Roberson 354acbff226SAlan Cox VM_OBJECT_LOCK(kmem_object); 3551e081f88SJeff Roberson for (i = 0; i < size; i += PAGE_SIZE) { 3561e081f88SJeff Roberson retry: 35795f24639SJeff Roberson m = vm_page_alloc(kmem_object, OFF_TO_IDX(offset + i), pflags); 358df8bae1dSRodney W. Grimes 359df8bae1dSRodney W. Grimes /* 3600d94caffSDavid Greenman * Ran out of space, free everything up and return. Don't need 3610d94caffSDavid Greenman * to lock page queues here as we know that the pages we got 3620d94caffSDavid Greenman * aren't on any queues. 363df8bae1dSRodney W. Grimes */ 364df8bae1dSRodney W. Grimes if (m == NULL) { 3651c7c3c6aSMatthew Dillon if ((flags & M_NOWAIT) == 0) { 366acbff226SAlan Cox VM_OBJECT_UNLOCK(kmem_object); 367c7003c69SAlan Cox vm_map_unlock(map); 368b18bfc3dSJohn Dyson VM_WAIT; 369c7003c69SAlan Cox vm_map_lock(map); 370acbff226SAlan Cox VM_OBJECT_LOCK(kmem_object); 371b18bfc3dSJohn Dyson goto retry; 372b18bfc3dSJohn Dyson } 373ff91d780STor Egge /* 374ff91d780STor Egge * Free the pages before removing the map entry. 375ff91d780STor Egge * They are already marked busy. Calling 376ff91d780STor Egge * vm_map_delete before the pages has been freed or 377ff91d780STor Egge * unbusied will cause a deadlock. 378ff91d780STor Egge */ 379ff91d780STor Egge while (i != 0) { 380ff91d780STor Egge i -= PAGE_SIZE; 381ff91d780STor Egge m = vm_page_lookup(kmem_object, 382ff91d780STor Egge OFF_TO_IDX(offset + i)); 38357123de6SAlan Cox vm_page_lock_queues(); 384a623fedeSAlan Cox vm_page_unwire(m, 0); 385ff91d780STor Egge vm_page_free(m); 38657123de6SAlan Cox vm_page_unlock_queues(); 387ff91d780STor Egge } 388acbff226SAlan Cox VM_OBJECT_UNLOCK(kmem_object); 389655c3490SKonstantin Belousov vm_map_delete(map, addr, addr + size); 390df8bae1dSRodney W. Grimes vm_map_unlock(map); 391f31c239dSAlan Cox return (0); 392df8bae1dSRodney W. Grimes } 3931e081f88SJeff Roberson if (flags & M_ZERO && (m->flags & PG_ZERO) == 0) 394fff6062aSAlan Cox pmap_zero_page(m); 39549c06616SAlan Cox m->valid = VM_PAGE_BITS_ALL; 3969f5c801bSAlan Cox KASSERT((m->flags & PG_UNMANAGED) != 0, 3979f5c801bSAlan Cox ("kmem_malloc: page %p is managed", m)); 398df8bae1dSRodney W. Grimes } 399acbff226SAlan Cox VM_OBJECT_UNLOCK(kmem_object); 400df8bae1dSRodney W. Grimes 401df8bae1dSRodney W. Grimes /* 4020d94caffSDavid Greenman * Mark map entry as non-pageable. Assert: vm_map_insert() will never 4030d94caffSDavid Greenman * be able to extend the previous entry so there will be a new entry 4040d94caffSDavid Greenman * exactly corresponding to this address range and it will have 4050d94caffSDavid Greenman * wired_count == 0. 406df8bae1dSRodney W. Grimes */ 407df8bae1dSRodney W. Grimes if (!vm_map_lookup_entry(map, addr, &entry) || 408df8bae1dSRodney W. Grimes entry->start != addr || entry->end != addr + size || 409c7003c69SAlan Cox entry->wired_count != 0) 410df8bae1dSRodney W. Grimes panic("kmem_malloc: entry not found or misaligned"); 411c7003c69SAlan Cox entry->wired_count = 1; 412df8bae1dSRodney W. Grimes 413ff5dcf25SAlan Cox /* 414ff5dcf25SAlan Cox * At this point, the kmem_object must be unlocked because 415ff5dcf25SAlan Cox * vm_map_simplify_entry() calls vm_object_deallocate(), which 416ff5dcf25SAlan Cox * locks the kmem_object. 417ff5dcf25SAlan Cox */ 418b7b2aac2SJohn Dyson vm_map_simplify_entry(map, entry); 419b7b2aac2SJohn Dyson 420df8bae1dSRodney W. Grimes /* 4210f3b612aSAlan Cox * Loop thru pages, entering them in the pmap. 422df8bae1dSRodney W. Grimes */ 423acbff226SAlan Cox VM_OBJECT_LOCK(kmem_object); 424ff5dcf25SAlan Cox for (i = 0; i < size; i += PAGE_SIZE) { 425a316d390SJohn Dyson m = vm_page_lookup(kmem_object, OFF_TO_IDX(offset + i)); 4261c7c3c6aSMatthew Dillon /* 4271c7c3c6aSMatthew Dillon * Because this is kernel_pmap, this call will not block. 4281c7c3c6aSMatthew Dillon */ 429eb2a0517SAlan Cox pmap_enter(kernel_pmap, addr + i, VM_PROT_ALL, m, VM_PROT_ALL, 430eb2a0517SAlan Cox TRUE); 43166bdd5d6SAlan Cox vm_page_wakeup(m); 432df8bae1dSRodney W. Grimes } 433ff5dcf25SAlan Cox VM_OBJECT_UNLOCK(kmem_object); 434df8bae1dSRodney W. Grimes vm_map_unlock(map); 435df8bae1dSRodney W. Grimes 436df8bae1dSRodney W. Grimes return (addr); 437df8bae1dSRodney W. Grimes } 438df8bae1dSRodney W. Grimes 439df8bae1dSRodney W. Grimes /* 4401c7c3c6aSMatthew Dillon * kmem_alloc_wait: 441df8bae1dSRodney W. Grimes * 442df8bae1dSRodney W. Grimes * Allocates pageable memory from a sub-map of the kernel. If the submap 443df8bae1dSRodney W. Grimes * has no room, the caller sleeps waiting for more memory in the submap. 444df8bae1dSRodney W. Grimes * 4451c7c3c6aSMatthew Dillon * This routine may block. 446df8bae1dSRodney W. Grimes */ 4470d94caffSDavid Greenman vm_offset_t 4480d94caffSDavid Greenman kmem_alloc_wait(map, size) 449df8bae1dSRodney W. Grimes vm_map_t map; 450df8bae1dSRodney W. Grimes vm_size_t size; 451df8bae1dSRodney W. Grimes { 452df8bae1dSRodney W. Grimes vm_offset_t addr; 45323955314SAlfred Perlstein 454df8bae1dSRodney W. Grimes size = round_page(size); 4553364c323SKonstantin Belousov if (!swap_reserve(size)) 4563364c323SKonstantin Belousov return (0); 457df8bae1dSRodney W. Grimes 458df8bae1dSRodney W. Grimes for (;;) { 459df8bae1dSRodney W. Grimes /* 4600d94caffSDavid Greenman * To make this work for more than one map, use the map's lock 4610d94caffSDavid Greenman * to lock out sleepers/wakers. 462df8bae1dSRodney W. Grimes */ 463df8bae1dSRodney W. Grimes vm_map_lock(map); 464e47ed70bSJohn Dyson if (vm_map_findspace(map, vm_map_min(map), size, &addr) == 0) 465df8bae1dSRodney W. Grimes break; 466df8bae1dSRodney W. Grimes /* no space now; see if we can ever get space */ 467df8bae1dSRodney W. Grimes if (vm_map_max(map) - vm_map_min(map) < size) { 468df8bae1dSRodney W. Grimes vm_map_unlock(map); 4693364c323SKonstantin Belousov swap_release(size); 470df8bae1dSRodney W. Grimes return (0); 471df8bae1dSRodney W. Grimes } 4729688f931SAlan Cox map->needs_wakeup = TRUE; 4738ce2d00aSPawel Jakub Dawidek vm_map_unlock_and_wait(map, 0); 474df8bae1dSRodney W. Grimes } 4753364c323SKonstantin Belousov vm_map_insert(map, NULL, 0, addr, addr + size, VM_PROT_ALL, 4763364c323SKonstantin Belousov VM_PROT_ALL, MAP_ACC_CHARGED); 477df8bae1dSRodney W. Grimes vm_map_unlock(map); 478df8bae1dSRodney W. Grimes return (addr); 479df8bae1dSRodney W. Grimes } 480df8bae1dSRodney W. Grimes 481df8bae1dSRodney W. Grimes /* 4821c7c3c6aSMatthew Dillon * kmem_free_wakeup: 483df8bae1dSRodney W. Grimes * 48424a1cce3SDavid Greenman * Returns memory to a submap of the kernel, and wakes up any processes 485df8bae1dSRodney W. Grimes * waiting for memory in that map. 486df8bae1dSRodney W. Grimes */ 4870d94caffSDavid Greenman void 4880d94caffSDavid Greenman kmem_free_wakeup(map, addr, size) 489df8bae1dSRodney W. Grimes vm_map_t map; 490df8bae1dSRodney W. Grimes vm_offset_t addr; 491df8bae1dSRodney W. Grimes vm_size_t size; 492df8bae1dSRodney W. Grimes { 49323955314SAlfred Perlstein 494df8bae1dSRodney W. Grimes vm_map_lock(map); 495655c3490SKonstantin Belousov (void) vm_map_delete(map, trunc_page(addr), round_page(addr + size)); 4969688f931SAlan Cox if (map->needs_wakeup) { 4979688f931SAlan Cox map->needs_wakeup = FALSE; 4989688f931SAlan Cox vm_map_wakeup(map); 4999688f931SAlan Cox } 500df8bae1dSRodney W. Grimes vm_map_unlock(map); 501df8bae1dSRodney W. Grimes } 502df8bae1dSRodney W. Grimes 503df8bae1dSRodney W. Grimes /* 5041c7c3c6aSMatthew Dillon * kmem_init: 5051c7c3c6aSMatthew Dillon * 5061c7c3c6aSMatthew Dillon * Create the kernel map; insert a mapping covering kernel text, 5071c7c3c6aSMatthew Dillon * data, bss, and all space allocated thus far (`boostrap' data). The 5081c7c3c6aSMatthew Dillon * new map will thus map the range between VM_MIN_KERNEL_ADDRESS and 5091c7c3c6aSMatthew Dillon * `start' as allocated, and the range between `start' and `end' as free. 510df8bae1dSRodney W. Grimes */ 5110d94caffSDavid Greenman void 5120d94caffSDavid Greenman kmem_init(start, end) 513df8bae1dSRodney W. Grimes vm_offset_t start, end; 514df8bae1dSRodney W. Grimes { 515030f2369SAlfred Perlstein vm_map_t m; 516df8bae1dSRodney W. Grimes 5172d8acc0fSJohn Dyson m = vm_map_create(kernel_pmap, VM_MIN_KERNEL_ADDRESS, end); 518c9267356SAlan Cox m->system_map = 1; 519df8bae1dSRodney W. Grimes vm_map_lock(m); 520df8bae1dSRodney W. Grimes /* N.B.: cannot use kgdb to debug, starting with this assignment ... */ 521df8bae1dSRodney W. Grimes kernel_map = m; 522c9267356SAlan Cox (void) vm_map_insert(m, NULL, (vm_ooffset_t) 0, 5235cfa90e9SAlan Cox #ifdef __amd64__ 5245cfa90e9SAlan Cox KERNBASE, 5255cfa90e9SAlan Cox #else 5265cfa90e9SAlan Cox VM_MIN_KERNEL_ADDRESS, 5275cfa90e9SAlan Cox #endif 5285cfa90e9SAlan Cox start, VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT); 529df8bae1dSRodney W. Grimes /* ... and ending with the completion of the above `insert' */ 530df8bae1dSRodney W. Grimes vm_map_unlock(m); 531df8bae1dSRodney W. Grimes } 53286f08737SRobert Watson 5339309e63cSRobert Watson #ifdef DIAGNOSTIC 53486f08737SRobert Watson /* 53586f08737SRobert Watson * Allow userspace to directly trigger the VM drain routine for testing 53686f08737SRobert Watson * purposes. 53786f08737SRobert Watson */ 53886f08737SRobert Watson static int 53986f08737SRobert Watson debug_vm_lowmem(SYSCTL_HANDLER_ARGS) 54086f08737SRobert Watson { 54186f08737SRobert Watson int error, i; 54286f08737SRobert Watson 54386f08737SRobert Watson i = 0; 54486f08737SRobert Watson error = sysctl_handle_int(oidp, &i, 0, req); 54586f08737SRobert Watson if (error) 54686f08737SRobert Watson return (error); 54786f08737SRobert Watson if (i) 54886f08737SRobert Watson EVENTHANDLER_INVOKE(vm_lowmem, 0); 54986f08737SRobert Watson return (0); 55086f08737SRobert Watson } 55186f08737SRobert Watson 55286f08737SRobert Watson SYSCTL_PROC(_debug, OID_AUTO, vm_lowmem, CTLTYPE_INT | CTLFLAG_RW, 0, 0, 55386f08737SRobert Watson debug_vm_lowmem, "I", "set to trigger vm_lowmem event"); 5549309e63cSRobert Watson #endif 555