vm_vfs.c revision 1.33
1 /* $NetBSD: vm_vfs.c,v 1.33 2012/06/03 16:46:08 rmind 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 1.33 2012/06/03 16:46:08 rmind 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 = NULL; 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 59 if (uobj == NULL) { 60 uobj = pgs[i]->uobject; 61 KASSERT(uobj != NULL); 62 mutex_enter(uobj->vmobjlock); 63 } else { 64 KASSERT(uobj == pgs[i]->uobject); 65 } 66 67 if (pgs[i]->flags & PG_PAGEOUT) { 68 KASSERT((pgs[i]->flags & PG_FAKE) == 0); 69 pageout++; 70 pgs[i]->flags &= ~PG_PAGEOUT; 71 pgs[i]->flags |= PG_RELEASED; 72 } 73 } 74 KASSERT(mutex_owned(uobj->vmobjlock)); 75 76 mutex_enter(&uvm_pageqlock); 77 uvm_page_unbusy(pgs, npages); 78 mutex_exit(&uvm_pageqlock); 79 mutex_exit(uobj->vmobjlock); 80 81 uvm_pagermapout((vaddr_t)bp->b_data, npages); 82 uvm_pageout_done(pageout); 83 84 if (BUF_ISWRITE(bp) && (bp->b_cflags & BC_AGE) != 0) { 85 mutex_enter(bp->b_objlock); 86 vwakeup(bp); 87 mutex_exit(bp->b_objlock); 88 } 89 90 putiobuf(bp); 91 92 kmem_free(pgs, npages * sizeof(*pgs)); 93 } 94 95 void 96 uvm_aio_biodone(struct buf *bp) 97 { 98 99 uvm_aio_aiodone(bp); 100 } 101 102 /* 103 * UBC 104 */ 105 106 #define PAGERFLAGS (PGO_SYNCIO | PGO_NOBLOCKALLOC | PGO_NOTIMESTAMP) 107 108 void 109 ubc_zerorange(struct uvm_object *uobj, off_t off, size_t len, int flags) 110 { 111 struct vm_page **pgs; 112 int maxpages = MIN(32, round_page(len) >> PAGE_SHIFT); 113 int rv, npages, i; 114 115 if (maxpages == 0) 116 return; 117 118 pgs = kmem_alloc(maxpages * sizeof(pgs), KM_SLEEP); 119 mutex_enter(uobj->vmobjlock); 120 while (len) { 121 npages = MIN(maxpages, round_page(len) >> PAGE_SHIFT); 122 memset(pgs, 0, npages * sizeof(struct vm_page *)); 123 rv = uobj->pgops->pgo_get(uobj, trunc_page(off), 124 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 125 0, PAGERFLAGS | PGO_PASTEOF); 126 KASSERT(npages > 0); 127 128 mutex_enter(uobj->vmobjlock); 129 for (i = 0; i < npages; i++) { 130 struct vm_page *pg; 131 uint8_t *start; 132 size_t chunkoff, chunklen; 133 134 pg = pgs[i]; 135 if (pg == NULL) 136 break; 137 138 KASSERT(pg->uobject != NULL); 139 KASSERT(uobj->vmobjlock == pg->uobject->vmobjlock); 140 141 chunkoff = off & PAGE_MASK; 142 chunklen = MIN(PAGE_SIZE - chunkoff, len); 143 start = (uint8_t *)pg->uanon + chunkoff; 144 145 memset(start, 0, chunklen); 146 pg->flags &= ~PG_CLEAN; 147 148 off += chunklen; 149 len -= chunklen; 150 } 151 uvm_page_unbusy(pgs, npages); 152 } 153 mutex_exit(uobj->vmobjlock); 154 kmem_free(pgs, maxpages * sizeof(pgs)); 155 } 156 157 #define len2npages(off, len) \ 158 ((round_page(off+len) - trunc_page(off)) >> PAGE_SHIFT) 159 160 int 161 ubc_uiomove(struct uvm_object *uobj, struct uio *uio, vsize_t todo, 162 int advice, int flags) 163 { 164 struct vm_page **pgs; 165 int npages = len2npages(uio->uio_offset, todo); 166 size_t pgalloc; 167 int i, rv, pagerflags; 168 vm_prot_t prot; 169 170 pgalloc = npages * sizeof(pgs); 171 pgs = kmem_alloc(pgalloc, KM_SLEEP); 172 173 pagerflags = PAGERFLAGS; 174 if (flags & UBC_WRITE) 175 pagerflags |= PGO_PASTEOF; 176 if (flags & UBC_FAULTBUSY) 177 pagerflags |= PGO_OVERWRITE; 178 179 prot = VM_PROT_READ; 180 if (flags & UBC_WRITE) 181 prot |= VM_PROT_WRITE; 182 183 mutex_enter(uobj->vmobjlock); 184 do { 185 npages = len2npages(uio->uio_offset, todo); 186 memset(pgs, 0, pgalloc); 187 rv = uobj->pgops->pgo_get(uobj, trunc_page(uio->uio_offset), 188 pgs, &npages, 0, prot, 0, pagerflags); 189 if (rv) 190 goto out; 191 192 mutex_enter(uobj->vmobjlock); 193 for (i = 0; i < npages; i++) { 194 struct vm_page *pg; 195 size_t xfersize; 196 off_t pageoff; 197 198 pg = pgs[i]; 199 if (pg == NULL) 200 break; 201 202 KASSERT(pg->uobject != NULL); 203 KASSERT(uobj->vmobjlock == pg->uobject->vmobjlock); 204 pageoff = uio->uio_offset & PAGE_MASK; 205 206 xfersize = MIN(MIN(todo, PAGE_SIZE), PAGE_SIZE-pageoff); 207 KASSERT(xfersize > 0); 208 rv = uiomove((uint8_t *)pg->uanon + pageoff, 209 xfersize, uio); 210 if (rv) { 211 uvm_page_unbusy(pgs, npages); 212 mutex_exit(uobj->vmobjlock); 213 goto out; 214 } 215 if (uio->uio_rw == UIO_WRITE) 216 pg->flags &= ~(PG_CLEAN | PG_FAKE); 217 todo -= xfersize; 218 } 219 uvm_page_unbusy(pgs, npages); 220 } while (todo); 221 mutex_exit(uobj->vmobjlock); 222 223 out: 224 kmem_free(pgs, pgalloc); 225 return rv; 226 } 227
Indexes created Tue Sep 30 17:09:57 GMT 2025