vm_vfs.c revision 1.29
1 /* $NetBSD: vm_vfs.c,v 1.29 2011/06/12 03:35:59 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 1.29 2011/06/12 03:35:59 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; 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 uvm_vnp_zerorange(struct vnode *vp, off_t off, size_t len) 106 { 107 struct uvm_object *uobj = &vp->v_uobj; 108 struct vm_page **pgs; 109 struct uvm_object *pguobj; 110 int maxpages = MIN(32, round_page(len) >> PAGE_SHIFT); 111 int rv, npages, i; 112 113 if (maxpages == 0) 114 return; 115 116 pgs = kmem_alloc(maxpages * sizeof(pgs), KM_SLEEP); 117 mutex_enter(uobj->vmobjlock); 118 while (len) { 119 npages = MIN(maxpages, round_page(len) >> PAGE_SHIFT); 120 memset(pgs, 0, npages * sizeof(struct vm_page *)); 121 rv = uobj->pgops->pgo_get(uobj, trunc_page(off), 122 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 123 0, PAGERFLAGS | PGO_PASTEOF); 124 KASSERT(npages > 0); 125 126 for (i = 0, pguobj = NULL; i < npages; i++) { 127 struct vm_page *pg; 128 uint8_t *start; 129 size_t chunkoff, chunklen; 130 131 pg = pgs[i]; 132 if (pg == NULL) 133 break; 134 if (pguobj == NULL) 135 pguobj = pg->uobject; 136 KASSERT(pguobj == pg->uobject); 137 138 chunkoff = off & PAGE_MASK; 139 chunklen = MIN(PAGE_SIZE - chunkoff, len); 140 start = (uint8_t *)pg->uanon + chunkoff; 141 142 memset(start, 0, chunklen); 143 pg->flags &= ~PG_CLEAN; 144 145 off += chunklen; 146 len -= chunklen; 147 } 148 mutex_enter(pguobj->vmobjlock); 149 uvm_page_unbusy(pgs, npages); 150 if (pguobj != uobj) { 151 mutex_exit(pguobj->vmobjlock); 152 mutex_enter(uobj->vmobjlock); 153 } 154 } 155 mutex_exit(uobj->vmobjlock); 156 kmem_free(pgs, maxpages * sizeof(pgs)); 157 158 return; 159 } 160 161 #define len2npages(off, len) \ 162 ((round_page(off+len) - trunc_page(off)) >> PAGE_SHIFT) 163 164 int 165 ubc_uiomove(struct uvm_object *uobj, struct uio *uio, vsize_t todo, 166 int advice, int flags) 167 { 168 struct vm_page **pgs; 169 struct uvm_object *pguobj; 170 int npages = len2npages(uio->uio_offset, todo); 171 size_t pgalloc; 172 int i, rv, pagerflags; 173 vm_prot_t prot; 174 175 pgalloc = npages * sizeof(pgs); 176 pgs = kmem_alloc(pgalloc, KM_SLEEP); 177 178 pagerflags = PAGERFLAGS; 179 if (flags & UBC_WRITE) 180 pagerflags |= PGO_PASTEOF; 181 if (flags & UBC_FAULTBUSY) 182 pagerflags |= PGO_OVERWRITE; 183 184 prot = VM_PROT_READ; 185 if (flags & UBC_WRITE) 186 prot |= VM_PROT_WRITE; 187 188 mutex_enter(uobj->vmobjlock); 189 do { 190 npages = len2npages(uio->uio_offset, todo); 191 memset(pgs, 0, pgalloc); 192 rv = uobj->pgops->pgo_get(uobj, trunc_page(uio->uio_offset), 193 pgs, &npages, 0, prot, 0, pagerflags); 194 if (rv) 195 goto out; 196 197 for (i = 0, pguobj = NULL; i < npages; i++) { 198 struct vm_page *pg; 199 size_t xfersize; 200 off_t pageoff; 201 202 pg = pgs[i]; 203 if (pg == NULL) 204 break; 205 if (pguobj == NULL) 206 pguobj = pg->uobject; 207 KASSERT(pguobj == pg->uobject); 208 209 pageoff = uio->uio_offset & PAGE_MASK; 210 xfersize = MIN(MIN(todo, PAGE_SIZE), PAGE_SIZE-pageoff); 211 KASSERT(xfersize > 0); 212 rv = uiomove((uint8_t *)pg->uanon + pageoff, 213 xfersize, uio); 214 if (rv) { 215 mutex_enter(pguobj->vmobjlock); 216 uvm_page_unbusy(pgs, npages); 217 mutex_exit(pguobj->vmobjlock); 218 goto out; 219 } 220 if (uio->uio_rw == UIO_WRITE) 221 pg->flags &= ~(PG_CLEAN | PG_FAKE); 222 todo -= xfersize; 223 } 224 mutex_enter(pguobj->vmobjlock); 225 uvm_page_unbusy(pgs, npages); 226 if (pguobj != uobj) { 227 mutex_exit(pguobj->vmobjlock); 228 mutex_enter(uobj->vmobjlock); 229 } 230 } while (todo); 231 mutex_exit(uobj->vmobjlock); 232 233 out: 234 kmem_free(pgs, pgalloc); 235 return rv; 236 } 237
Indexes created Tue Sep 30 07:10:03 GMT 2025