vm_vfs.c revision 1.22 1 /* $NetBSD: vm_vfs.c,v 1.22 2010/09/09 10:01:25 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 1.22 2010/09/09 10:01:25 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 }
66 }
67
68 uvm_pagermapout((vaddr_t)bp->b_data, npages);
69 uvm_pageout_done(pageout);
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 if (BUF_ISWRITE(bp) && (bp->b_cflags & BC_AGE) != 0) {
82 mutex_enter(bp->b_objlock);
83 vwakeup(bp);
84 mutex_exit(bp->b_objlock);
85 }
86
87 putiobuf(bp);
88
89 kmem_free(pgs, npages * sizeof(*pgs));
90 }
91
92 void
93 uvm_aio_biodone(struct buf *bp)
94 {
95
96 uvm_aio_aiodone(bp);
97 }
98
99 /*
100 * UBC
101 */
102
103 #define PAGERFLAGS (PGO_SYNCIO | PGO_NOBLOCKALLOC | PGO_NOTIMESTAMP)
104
105 void
106 uvm_vnp_zerorange(struct vnode *vp, off_t off, size_t len)
107 {
108 struct uvm_object *uobj = &vp->v_uobj;
109 struct vm_page **pgs;
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; 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
135 chunkoff = off & PAGE_MASK;
136 chunklen = MIN(PAGE_SIZE - chunkoff, len);
137 start = (uint8_t *)pg->uanon + chunkoff;
138
139 memset(start, 0, chunklen);
140 pg->flags &= ~PG_CLEAN;
141
142 off += chunklen;
143 len -= chunklen;
144 }
145 mutex_enter(&uobj->vmobjlock);
146 uvm_page_unbusy(pgs, npages);
147 }
148 mutex_exit(&uobj->vmobjlock);
149 kmem_free(pgs, maxpages * sizeof(pgs));
150
151 return;
152 }
153
154 #define len2npages(off, len) \
155 ((round_page(off+len) - trunc_page(off)) >> PAGE_SHIFT)
156
157 int
158 ubc_uiomove(struct uvm_object *uobj, struct uio *uio, vsize_t todo,
159 int advice, int flags)
160 {
161 struct vm_page **pgs;
162 int npages = len2npages(uio->uio_offset, todo);
163 size_t pgalloc;
164 int i, rv, pagerflags;
165
166 pgalloc = npages * sizeof(pgs);
167 pgs = kmem_alloc(pgalloc, KM_SLEEP);
168
169 pagerflags = PAGERFLAGS;
170 if (flags & UBC_WRITE)
171 pagerflags |= PGO_PASTEOF;
172 if (flags & UBC_FAULTBUSY)
173 pagerflags |= PGO_OVERWRITE;
174
175 mutex_enter(&uobj->vmobjlock);
176 do {
177 npages = len2npages(uio->uio_offset, todo);
178 memset(pgs, 0, pgalloc);
179 rv = uobj->pgops->pgo_get(uobj, trunc_page(uio->uio_offset),
180 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 0,
181 pagerflags);
182 if (rv)
183 goto out;
184
185 for (i = 0; i < npages; i++) {
186 struct vm_page *pg;
187 size_t xfersize;
188 off_t pageoff;
189
190 pg = pgs[i];
191 if (pg == NULL)
192 break;
193
194 pageoff = uio->uio_offset & PAGE_MASK;
195 xfersize = MIN(MIN(todo, PAGE_SIZE), PAGE_SIZE-pageoff);
196 KASSERT(xfersize > 0);
197 uiomove((uint8_t *)pg->uanon + pageoff,
198 xfersize, uio);
199 if (uio->uio_rw == UIO_WRITE)
200 pg->flags &= ~(PG_CLEAN | PG_FAKE);
201 todo -= xfersize;
202 }
203 mutex_enter(&uobj->vmobjlock);
204 uvm_page_unbusy(pgs, npages);
205 } while (todo);
206 mutex_exit(&uobj->vmobjlock);
207
208 out:
209 kmem_free(pgs, pgalloc);
210 return rv;
211 }
212