vm_vfs.c revision 1.20
1 /* $NetBSD: vm_vfs.c,v 1.20 2010/09/06 21:33:07 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 1.20 2010/09/06 21:33:07 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 int i, npages = bp->b_bufsize >> PAGE_SHIFT; 51 struct vm_page **pgs; 52 vaddr_t va; 53 int pageout = 0; 54 55 pgs = kmem_alloc(npages * sizeof(*pgs), KM_SLEEP); 56 for (i = 0; i < npages; i++) { 57 va = (vaddr_t)bp->b_data + (i << PAGE_SHIFT); 58 pgs[i] = uvm_pageratop(va); 59 if (pgs[i]->flags & PG_PAGEOUT) { 60 KASSERT((pgs[i]->flags & PG_FAKE) == 0); 61 pageout++; 62 pgs[i]->flags &= ~PG_PAGEOUT; 63 } 64 } 65 66 uvm_pagermapout((vaddr_t)bp->b_data, npages); 67 uvm_pageout_done(pageout); 68 uvm_page_unbusy(pgs, npages); 69 70 if (BUF_ISWRITE(bp) && (bp->b_cflags & BC_AGE) != 0) { 71 mutex_enter(bp->b_objlock); 72 vwakeup(bp); 73 mutex_exit(bp->b_objlock); 74 } 75 76 putiobuf(bp); 77 78 kmem_free(pgs, npages * sizeof(*pgs)); 79 } 80 81 void 82 uvm_aio_biodone(struct buf *bp) 83 { 84 85 uvm_aio_aiodone(bp); 86 } 87 88 /* 89 * UBC 90 */ 91 92 #define PAGERFLAGS (PGO_SYNCIO | PGO_NOBLOCKALLOC | PGO_NOTIMESTAMP) 93 94 void 95 uvm_vnp_zerorange(struct vnode *vp, off_t off, size_t len) 96 { 97 struct uvm_object *uobj = &vp->v_uobj; 98 struct vm_page **pgs; 99 int maxpages = MIN(32, round_page(len) >> PAGE_SHIFT); 100 int rv, npages, i; 101 102 if (maxpages == 0) 103 return; 104 105 pgs = kmem_alloc(maxpages * sizeof(pgs), KM_SLEEP); 106 while (len) { 107 npages = MIN(maxpages, round_page(len) >> PAGE_SHIFT); 108 memset(pgs, 0, npages * sizeof(struct vm_page *)); 109 mutex_enter(&uobj->vmobjlock); 110 rv = uobj->pgops->pgo_get(uobj, trunc_page(off), 111 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 112 0, PAGERFLAGS | PGO_PASTEOF); 113 KASSERT(npages > 0); 114 115 for (i = 0; i < npages; i++) { 116 struct vm_page *pg; 117 uint8_t *start; 118 size_t chunkoff, chunklen; 119 120 pg = pgs[i]; 121 if (pg == NULL) 122 break; 123 124 chunkoff = off & PAGE_MASK; 125 chunklen = MIN(PAGE_SIZE - chunkoff, len); 126 start = (uint8_t *)pg->uanon + chunkoff; 127 128 memset(start, 0, chunklen); 129 pg->flags &= ~PG_CLEAN; 130 131 off += chunklen; 132 len -= chunklen; 133 } 134 uvm_page_unbusy(pgs, npages); 135 } 136 kmem_free(pgs, maxpages * sizeof(pgs)); 137 138 return; 139 } 140 141 #define len2npages(off, len) \ 142 ((round_page(off+len) - trunc_page(off)) >> PAGE_SHIFT) 143 144 int 145 ubc_uiomove(struct uvm_object *uobj, struct uio *uio, vsize_t todo, 146 int advice, int flags) 147 { 148 struct vm_page **pgs; 149 int npages = len2npages(uio->uio_offset, todo); 150 size_t pgalloc; 151 int i, rv, pagerflags; 152 153 pgalloc = npages * sizeof(pgs); 154 pgs = kmem_alloc(pgalloc, KM_SLEEP); 155 156 pagerflags = PAGERFLAGS; 157 if (flags & UBC_WRITE) 158 pagerflags |= PGO_PASTEOF; 159 if (flags & UBC_FAULTBUSY) 160 pagerflags |= PGO_OVERWRITE; 161 162 do { 163 npages = len2npages(uio->uio_offset, todo); 164 memset(pgs, 0, pgalloc); 165 mutex_enter(&uobj->vmobjlock); 166 rv = uobj->pgops->pgo_get(uobj, trunc_page(uio->uio_offset), 167 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 0, 168 pagerflags); 169 if (rv) 170 goto out; 171 172 for (i = 0; i < npages; i++) { 173 struct vm_page *pg; 174 size_t xfersize; 175 off_t pageoff; 176 177 pg = pgs[i]; 178 if (pg == NULL) 179 break; 180 181 pageoff = uio->uio_offset & PAGE_MASK; 182 xfersize = MIN(MIN(todo, PAGE_SIZE), PAGE_SIZE-pageoff); 183 KASSERT(xfersize > 0); 184 uiomove((uint8_t *)pg->uanon + pageoff, 185 xfersize, uio); 186 if (uio->uio_rw == UIO_WRITE) 187 pg->flags &= ~(PG_CLEAN | PG_FAKE); 188 todo -= xfersize; 189 } 190 uvm_page_unbusy(pgs, npages); 191 } while (todo); 192 193 out: 194 kmem_free(pgs, pgalloc); 195 return rv; 196 } 197
Indexes created Tue Sep 30 11:09:46 GMT 2025