vm_vfs.c revision 1.26
1 /* $NetBSD: vm_vfs.c,v 1.26 2011/02/27 13:37:39 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 2008 Antti Kantee. All Rights Reserved. 5 * 6 * Development of this software was supported by the 7 * Finnish Cultural Foundation. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 19 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 21 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: vm_vfs.c,v 1.26 2011/02/27 13:37:39 pooka Exp $"); 33 34 #include <sys/param.h> 35 36 #include <sys/buf.h> 37 #include <sys/vnode.h> 38 39 #include <uvm/uvm.h> 40 #include <uvm/uvm_readahead.h> 41 42 /* 43 * release resources held during async io. this is almost the 44 * same as uvm_aio_aiodone() from uvm_pager.c and only lacks the 45 * call to uvm_aio_aiodone_pages(): unbusies pages directly here. 46 */ 47 void 48 uvm_aio_aiodone(struct buf *bp) 49 { 50 struct uvm_object *uobj; 51 int i, npages = bp->b_bufsize >> PAGE_SHIFT; 52 struct vm_page **pgs; 53 vaddr_t va; 54 int pageout = 0; 55 56 KASSERT(npages > 0); 57 pgs = kmem_alloc(npages * sizeof(*pgs), KM_SLEEP); 58 for (i = 0; i < npages; i++) { 59 va = (vaddr_t)bp->b_data + (i << PAGE_SHIFT); 60 pgs[i] = uvm_pageratop(va); 61 if (pgs[i]->flags & PG_PAGEOUT) { 62 KASSERT((pgs[i]->flags & PG_FAKE) == 0); 63 pageout++; 64 pgs[i]->flags &= ~PG_PAGEOUT; 65 pgs[i]->flags |= PG_RELEASED; 66 } 67 } 68 69 uvm_pagermapout((vaddr_t)bp->b_data, npages); 70 71 /* get uobj because we need it after pages might be recycled */ 72 uobj = pgs[0]->uobject; 73 KASSERT(uobj); 74 75 mutex_enter(&uobj->vmobjlock); 76 mutex_enter(&uvm_pageqlock); 77 uvm_page_unbusy(pgs, npages); 78 mutex_exit(&uvm_pageqlock); 79 mutex_exit(&uobj->vmobjlock); 80 81 uvm_pageout_done(pageout); 82 83 if (BUF_ISWRITE(bp) && (bp->b_cflags & BC_AGE) != 0) { 84 mutex_enter(bp->b_objlock); 85 vwakeup(bp); 86 mutex_exit(bp->b_objlock); 87 } 88 89 putiobuf(bp); 90 91 kmem_free(pgs, npages * sizeof(*pgs)); 92 } 93 94 void 95 uvm_aio_biodone(struct buf *bp) 96 { 97 98 uvm_aio_aiodone(bp); 99 } 100 101 /* 102 * UBC 103 */ 104 105 #define PAGERFLAGS (PGO_SYNCIO | PGO_NOBLOCKALLOC | PGO_NOTIMESTAMP) 106 107 void 108 uvm_vnp_zerorange(struct vnode *vp, off_t off, size_t len) 109 { 110 struct uvm_object *uobj = &vp->v_uobj; 111 struct vm_page **pgs; 112 struct uvm_object *pguobj; 113 int maxpages = MIN(32, round_page(len) >> PAGE_SHIFT); 114 int rv, npages, i; 115 116 if (maxpages == 0) 117 return; 118 119 pgs = kmem_alloc(maxpages * sizeof(pgs), KM_SLEEP); 120 mutex_enter(&uobj->vmobjlock); 121 while (len) { 122 npages = MIN(maxpages, round_page(len) >> PAGE_SHIFT); 123 memset(pgs, 0, npages * sizeof(struct vm_page *)); 124 rv = uobj->pgops->pgo_get(uobj, trunc_page(off), 125 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 126 0, PAGERFLAGS | PGO_PASTEOF); 127 KASSERT(npages > 0); 128 129 for (i = 0, pguobj = NULL; 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 if (pguobj == NULL) 138 pguobj = pg->uobject; 139 KASSERT(pguobj == pg->uobject); 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 mutex_enter(&pguobj->vmobjlock); 152 uvm_page_unbusy(pgs, npages); 153 if (pguobj != uobj) { 154 mutex_exit(&pguobj->vmobjlock); 155 mutex_enter(&uobj->vmobjlock); 156 } 157 } 158 mutex_exit(&uobj->vmobjlock); 159 kmem_free(pgs, maxpages * sizeof(pgs)); 160 161 return; 162 } 163 164 #define len2npages(off, len) \ 165 ((round_page(off+len) - trunc_page(off)) >> PAGE_SHIFT) 166 167 int 168 ubc_uiomove(struct uvm_object *uobj, struct uio *uio, vsize_t todo, 169 int advice, int flags) 170 { 171 struct vm_page **pgs; 172 struct uvm_object *pguobj; 173 int npages = len2npages(uio->uio_offset, todo); 174 size_t pgalloc; 175 int i, rv, pagerflags; 176 177 pgalloc = npages * sizeof(pgs); 178 pgs = kmem_alloc(pgalloc, KM_SLEEP); 179 180 pagerflags = PAGERFLAGS; 181 if (flags & UBC_WRITE) 182 pagerflags |= PGO_PASTEOF; 183 if (flags & UBC_FAULTBUSY) 184 pagerflags |= PGO_OVERWRITE; 185 186 mutex_enter(&uobj->vmobjlock); 187 do { 188 npages = len2npages(uio->uio_offset, todo); 189 memset(pgs, 0, pgalloc); 190 rv = uobj->pgops->pgo_get(uobj, trunc_page(uio->uio_offset), 191 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 0, 192 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 07:10:03 GMT 2025