vm_vfs.c revision 1.17 1 /* $NetBSD: vm_vfs.c,v 1.17 2010/08/19 02:07:11 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 1.17 2010/08/19 02:07:11 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_zalloc(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, off, pgs, &npages, 0,
111 VM_PROT_READ | VM_PROT_WRITE, 0, PAGERFLAGS | PGO_PASTEOF);
112 KASSERT(npages > 0);
113
114 for (i = 0; i < npages; i++) {
115 uint8_t *start;
116 size_t chunkoff, chunklen;
117
118 chunkoff = off & PAGE_MASK;
119 chunklen = MIN(PAGE_SIZE - chunkoff, len);
120 start = (uint8_t *)pgs[i]->uanon + chunkoff;
121
122 memset(start, 0, chunklen);
123 pgs[i]->flags &= ~PG_CLEAN;
124
125 off += chunklen;
126 len -= chunklen;
127 }
128 uvm_page_unbusy(pgs, npages);
129 }
130 kmem_free(pgs, maxpages * sizeof(pgs));
131
132 return;
133 }
134
135 /* dumdidumdum */
136 #define len2npages(off, len) \
137 (((((len) + PAGE_MASK) & ~(PAGE_MASK)) >> PAGE_SHIFT) \
138 + (((off & PAGE_MASK) + (len & PAGE_MASK)) > PAGE_SIZE))
139
140 int
141 ubc_uiomove(struct uvm_object *uobj, struct uio *uio, vsize_t todo,
142 int advice, int flags)
143 {
144 struct vm_page **pgs;
145 int npages = len2npages(uio->uio_offset, todo);
146 size_t pgalloc;
147 int i, rv, pagerflags;
148
149 pgalloc = npages * sizeof(pgs);
150 pgs = kmem_zalloc(pgalloc, KM_SLEEP);
151
152 pagerflags = PAGERFLAGS;
153 if (flags & UBC_WRITE)
154 pagerflags |= PGO_PASTEOF;
155 if (flags & UBC_FAULTBUSY)
156 pagerflags |= PGO_OVERWRITE;
157
158 do {
159 mutex_enter(&uobj->vmobjlock);
160 rv = uobj->pgops->pgo_get(uobj, uio->uio_offset & ~PAGE_MASK,
161 pgs, &npages, 0, VM_PROT_READ | VM_PROT_WRITE, 0,
162 pagerflags);
163 if (rv)
164 goto out;
165
166 for (i = 0; i < npages; i++) {
167 size_t xfersize;
168 off_t pageoff;
169
170 pageoff = uio->uio_offset & PAGE_MASK;
171 xfersize = MIN(MIN(todo, PAGE_SIZE), PAGE_SIZE-pageoff);
172 KASSERT(xfersize > 0);
173 uiomove((uint8_t *)pgs[i]->uanon + pageoff,
174 xfersize, uio);
175 if (uio->uio_rw == UIO_WRITE)
176 pgs[i]->flags &= ~(PG_CLEAN | PG_FAKE);
177 todo -= xfersize;
178 }
179 uvm_page_unbusy(pgs, npages);
180 } while (todo);
181
182 out:
183 kmem_free(pgs, pgalloc);
184 return rv;
185 }
186