vm_vfs.c revision 1.30
1 /* $NetBSD: vm_vfs.c,v 1.30 2011/06/16 09:21:03 hannken Exp $ */ 2 3 /* 4 * Copyright (c) 2008-2011 Antti Kantee. All Rights Reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __KERNEL_RCSID(0, "$NetBSD: vm_vfs.c,v 1.30 2011/06/16 09:21:03 hannken Exp $"); 30 31 #include <sys/param.h> 32 33 #include <sys/buf.h> 34 #include <sys/vnode.h> 35 36 #include <uvm/uvm.h> 37 #include <uvm/uvm_readahead.h> 38 39 /* 40 * release resources held during async io. this is almost the 41 * same as uvm_aio_aiodone() from uvm_pager.c and only lacks the 42 * call to uvm_aio_aiodone_pages(): unbusies pages directly here. 43 */ 44 void 45 uvm_aio_aiodone(struct buf *bp) 46 { 47 struct uvm_object *uobj; 48 int i, npages = bp->b_bufsize >> PAGE_SHIFT; 49 struct vm_page **pgs; 50 vaddr_t va; 51 int pageout = 0; 52 53 KASSERT(npages > 0); 54 pgs = kmem_alloc(npages * sizeof(*pgs), KM_SLEEP); 55 for (i = 0; i < npages; i++) { 56 va = (vaddr_t)bp->b_data + (i << PAGE_SHIFT); 57 pgs[i] = uvm_pageratop(va); 58 if (pgs[i]->flags & PG_PAGEOUT) { 59 KASSERT((pgs[i]->flags & PG_FAKE) == 0); 60 pageout++; 61 pgs[i]->flags &= ~PG_PAGEOUT; 62 pgs[i]->flags |= PG_RELEASED; 63 } 64 } 65 66 uvm_pagermapout((vaddr_t)bp->b_data, npages); 67 68 /* get uobj because we need it after pages might be recycled */ 69 uobj = pgs[0]->uobject; 70 KASSERT(uobj); 71 72 mutex_enter(uobj->vmobjlock); 73 mutex_enter(&uvm_pageqlock); 74 uvm_page_unbusy(pgs, npages); 75 mutex_exit(&uvm_pageqlock); 76 mutex_exit(uobj->vmobjlock); 77 78 uvm_pageout_done(pageout); 79 80 if (BUF_ISWRITE(bp) && (bp->b_cflags & BC_AGE) != 0) { 81 mutex_enter(bp->b_objlock); 82 vwakeup(bp); 83 mutex_exit(bp->b_objlock); 84 } 85 86 putiobuf(bp); 87 88 kmem_free(pgs, npages * sizeof(*pgs)); 89 } 90 91 void 92 uvm_aio_biodone(struct buf *bp) 93 { 94 95 uvm_aio_aiodone(bp); 96 } 97 98 /* 99 * UBC 100 */ 101 102 #define PAGERFLAGS (PGO_SYNCIO | PGO_NOBLOCKALLOC | PGO_NOTIMESTAMP) 103 104 void 105 ubc_zerorange(struct uvm_object *uobj, off_t off, size_t len, int flags) 106 { 107 struct vm_page **pgs; 108 struct uvm_object *pguobj; 109 int maxpages = MIN(32, round_page(len) >> PAGE_SHIFT); 110 int rv, npages, i; 111 112 if (maxpages == 0) 113 return; 114 115 pgs = kmem_alloc(maxpages * sizeof(pgs), KM_SLEEP); 116 mutex_enter(uobj->vmobjlock); 117 while (len) { 118 npages = MIN(maxpages, round_page(len) >> PAGE_SHIFT); 119 memset(pgs, 0, npages * sizeof(struct vm_page *)); 120 rv = uobj->pgops->pgo_get(uobj, trunc_page(off), 121 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 122 0, PAGERFLAGS | PGO_PASTEOF); 123 KASSERT(npages > 0); 124 125 for (i = 0, pguobj = NULL; i < npages; i++) { 126 struct vm_page *pg; 127 uint8_t *start; 128 size_t chunkoff, chunklen; 129 130 pg = pgs[i]; 131 if (pg == NULL) 132 break; 133 if (pguobj == NULL) 134 pguobj = pg->uobject; 135 KASSERT(pguobj == pg->uobject); 136 137 chunkoff = off & PAGE_MASK; 138 chunklen = MIN(PAGE_SIZE - chunkoff, len); 139 start = (uint8_t *)pg->uanon + chunkoff; 140 141 memset(start, 0, chunklen); 142 pg->flags &= ~PG_CLEAN; 143 144 off += chunklen; 145 len -= chunklen; 146 } 147 mutex_enter(pguobj->vmobjlock); 148 uvm_page_unbusy(pgs, npages); 149 if (pguobj != uobj) { 150 mutex_exit(pguobj->vmobjlock); 151 mutex_enter(uobj->vmobjlock); 152 } 153 } 154 mutex_exit(uobj->vmobjlock); 155 kmem_free(pgs, maxpages * sizeof(pgs)); 156 157 return; 158 } 159 160 #define len2npages(off, len) \ 161 ((round_page(off+len) - trunc_page(off)) >> PAGE_SHIFT) 162 163 int 164 ubc_uiomove(struct uvm_object *uobj, struct uio *uio, vsize_t todo, 165 int advice, int flags) 166 { 167 struct vm_page **pgs; 168 struct uvm_object *pguobj; 169 int npages = len2npages(uio->uio_offset, todo); 170 size_t pgalloc; 171 int i, rv, pagerflags; 172 vm_prot_t prot; 173 174 pgalloc = npages * sizeof(pgs); 175 pgs = kmem_alloc(pgalloc, KM_SLEEP); 176 177 pagerflags = PAGERFLAGS; 178 if (flags & UBC_WRITE) 179 pagerflags |= PGO_PASTEOF; 180 if (flags & UBC_FAULTBUSY) 181 pagerflags |= PGO_OVERWRITE; 182 183 prot = VM_PROT_READ; 184 if (flags & UBC_WRITE) 185 prot |= VM_PROT_WRITE; 186 187 mutex_enter(uobj->vmobjlock); 188 do { 189 npages = len2npages(uio->uio_offset, todo); 190 memset(pgs, 0, pgalloc); 191 rv = uobj->pgops->pgo_get(uobj, trunc_page(uio->uio_offset), 192 pgs, &npages, 0, prot, 0, pagerflags); 193 if (rv) 194 goto out; 195 196 for (i = 0, pguobj = NULL; i < npages; i++) { 197 struct vm_page *pg; 198 size_t xfersize; 199 off_t pageoff; 200 201 pg = pgs[i]; 202 if (pg == NULL) 203 break; 204 if (pguobj == NULL) 205 pguobj = pg->uobject; 206 KASSERT(pguobj == pg->uobject); 207 208 pageoff = uio->uio_offset & PAGE_MASK; 209 xfersize = MIN(MIN(todo, PAGE_SIZE), PAGE_SIZE-pageoff); 210 KASSERT(xfersize > 0); 211 rv = uiomove((uint8_t *)pg->uanon + pageoff, 212 xfersize, uio); 213 if (rv) { 214 mutex_enter(pguobj->vmobjlock); 215 uvm_page_unbusy(pgs, npages); 216 mutex_exit(pguobj->vmobjlock); 217 goto out; 218 } 219 if (uio->uio_rw == UIO_WRITE) 220 pg->flags &= ~(PG_CLEAN | PG_FAKE); 221 todo -= xfersize; 222 } 223 mutex_enter(pguobj->vmobjlock); 224 uvm_page_unbusy(pgs, npages); 225 if (pguobj != uobj) { 226 mutex_exit(pguobj->vmobjlock); 227 mutex_enter(uobj->vmobjlock); 228 } 229 } while (todo); 230 mutex_exit(uobj->vmobjlock); 231 232 out: 233 kmem_free(pgs, pgalloc); 234 return rv; 235 } 236
Indexes created Tue Sep 30 11:09:46 GMT 2025