1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
23 /* All Rights Reserved */
24
25
26 /*
27 * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
28 * Use is subject to license terms.
29 */
30
31 #pragma ident "%Z%%M% %I% %E% SMI"
32
33 #include <sys/types.h>
34 #include <sys/buf.h>
35 #include <sys/cmn_err.h>
36 #include <sys/conf.h>
37 #include <sys/debug.h>
38 #include <sys/errno.h>
39 #include <sys/fbuf.h>
40 #include <sys/kmem.h>
41 #include <sys/param.h>
42 #include <sys/sysmacros.h>
43 #include <sys/vfs.h>
44 #include <sys/cred.h>
45 #include <sys/vnode.h>
46 #include <vm/hat.h>
47 #include <vm/as.h>
48 #include <vm/seg.h>
49 #include <vm/seg_kmem.h>
50 #include <vm/seg_map.h>
51 #include <vm/seg_kpm.h>
52
53
54 /*
55 * Pseudo-bio routines which use a segmap mapping to address file data.
56 */
57
58 /*
59 * Return a pointer to locked kernel virtual address for
60 * the given <vp, off> for len bytes. It is not allowed to
61 * have the offset cross a MAXBSIZE boundary over len bytes.
62 */
63 int
fbread(vnode_t * vp,offset_t off,uint_t len,enum seg_rw rw,struct fbuf ** fbpp)64 fbread(vnode_t *vp, offset_t off, uint_t len, enum seg_rw rw,
65 struct fbuf **fbpp)
66 {
67 caddr_t addr;
68 ulong_t o;
69 struct fbuf *fbp;
70 faultcode_t err;
71 caddr_t raddr;
72 uint_t rsize;
73 uintptr_t pgoff = PAGEOFFSET;
74
75 o = (ulong_t)(off & (offset_t)MAXBOFFSET);
76 if (o + len > MAXBSIZE)
77 cmn_err(CE_PANIC, "fbread");
78
79 if (segmap_kpm) {
80 addr = segmap_getmapflt(segkmap, vp, off & (offset_t)MAXBMASK,
81 MAXBSIZE, SM_LOCKPROTO, rw);
82 } else {
83 addr = segmap_getmapflt(segkmap, vp,
84 off & (offset_t)MAXBMASK, MAXBSIZE, 0, rw);
85 }
86
87 raddr = (caddr_t)((uintptr_t)(addr + o) & ~pgoff);
88 rsize = (((uintptr_t)(addr + o) + len + pgoff) & ~pgoff) -
89 (uintptr_t)raddr;
90
91 err = segmap_fault(kas.a_hat, segkmap, raddr, rsize, F_SOFTLOCK, rw);
92 if (err) {
93 (void) segmap_release(segkmap, addr, 0);
94 if (FC_CODE(err) == FC_OBJERR)
95 return (FC_ERRNO(err));
96 else
97 return (EIO);
98 }
99
100 *fbpp = fbp = kmem_alloc(sizeof (struct fbuf), KM_SLEEP);
101 fbp->fb_addr = addr + o;
102 fbp->fb_count = len;
103 return (0);
104 }
105
106 /*
107 * Similar to fbread() but we call segmap_pagecreate instead of using
108 * segmap_fault for SOFTLOCK to create the pages without using VOP_GETPAGE
109 * and then we zero up to the length rounded to a page boundary.
110 * XXX - this won't work right when bsize < PAGESIZE!!!
111 */
112 void
fbzero(vnode_t * vp,offset_t off,uint_t len,struct fbuf ** fbpp)113 fbzero(vnode_t *vp, offset_t off, uint_t len, struct fbuf **fbpp)
114 {
115 caddr_t addr;
116 ulong_t o, zlen;
117 struct fbuf *fbp;
118
119 o = (ulong_t)(off & MAXBOFFSET);
120 if (o + len > MAXBSIZE)
121 cmn_err(CE_PANIC, "fbzero: Bad offset/length");
122
123 if (segmap_kpm) {
124 addr = segmap_getmapflt(segkmap, vp, off & (offset_t)MAXBMASK,
125 MAXBSIZE, SM_PAGECREATE, S_WRITE) + o;
126 } else {
127 addr = segmap_getmap(segkmap, vp, off & (offset_t)MAXBMASK) + o;
128 }
129
130 *fbpp = fbp = kmem_alloc(sizeof (struct fbuf), KM_SLEEP);
131 fbp->fb_addr = addr;
132 fbp->fb_count = len;
133
134 (void) segmap_pagecreate(segkmap, addr, len, 1);
135
136 /*
137 * Now we zero all the memory in the mapping we are interested in.
138 */
139 zlen = (caddr_t)ptob(btopr((uintptr_t)(len + addr))) - addr;
140 if (zlen < len || (o + zlen > MAXBSIZE))
141 cmn_err(CE_PANIC, "fbzero: Bad zlen");
142 bzero(addr, zlen);
143 }
144
145 /*
146 * FBCOMMON() is the common code for fbrelse, fbwrite and variants thereof:
147 *
148 * fbrelse() release fbp
149 * fbwrite() direct write
150 * fbdwrite() delayed write
151 */
152 #define FBCOMMON(fbp, rw, flags, howtoreturn) \
153 { \
154 caddr_t addr; \
155 size_t size; \
156 uintptr_t pgoff = PAGEOFFSET; \
157 addr = (caddr_t)((uintptr_t)fbp->fb_addr & ~pgoff); \
158 size = ((fbp->fb_addr - addr) + fbp->fb_count + pgoff) & ~pgoff; \
159 (void) segmap_fault(kas.a_hat, segkmap, addr, size, F_SOFTUNLOCK, rw); \
160 addr = (caddr_t)((uintptr_t)fbp->fb_addr & MAXBMASK); \
161 kmem_free(fbp, sizeof (struct fbuf)); \
162 howtoreturn(segmap_release(segkmap, addr, flags)); \
163 }
164
165 void
fbrelse(struct fbuf * fbp,enum seg_rw rw)166 fbrelse(struct fbuf *fbp, enum seg_rw rw)
167 {
168 FBCOMMON(fbp, rw, 0, (void))
169 }
170
171 int
fbwrite(struct fbuf * fbp)172 fbwrite(struct fbuf *fbp)
173 {
174 FBCOMMON(fbp, S_WRITE, SM_WRITE, return)
175 }
176
177 int
fbdwrite(struct fbuf * fbp)178 fbdwrite(struct fbuf *fbp)
179 {
180 FBCOMMON(fbp, S_WRITE, 0, return)
181 }
182
183 /*
184 * Perform a synchronous indirect write of the given block number
185 * on the given device, using the given fbuf. Upon return the fbp
186 * is invalid.
187 */
188 int
fbiwrite(struct fbuf * fbp,vnode_t * devvp,daddr_t bn,int bsize)189 fbiwrite(struct fbuf *fbp, vnode_t *devvp, daddr_t bn, int bsize)
190 {
191 struct buf *bp;
192 int error, fberror;
193
194 /*
195 * Allocate a temp bp using pageio_setup, but then use it
196 * for physio to the area mapped by fbuf which is currently
197 * all locked down in place.
198 *
199 * XXX - need to have a generalized bp header facility
200 * which we build up pageio_setup on top of. Other places
201 * (like here and in device drivers for the raw I/O case)
202 * could then use these new facilities in a more straight
203 * forward fashion instead of playing all these games.
204 */
205 bp = pageio_setup((struct page *)NULL, fbp->fb_count, devvp, B_WRITE);
206 bp->b_flags &= ~B_PAGEIO; /* XXX */
207 bp->b_un.b_addr = fbp->fb_addr;
208
209 bp->b_blkno = bn * btod(bsize);
210 bp->b_dev = cmpdev(devvp->v_rdev); /* store in old dev format */
211 bp->b_edev = devvp->v_rdev;
212 bp->b_proc = NULL; /* i.e. the kernel */
213
214 (void) bdev_strategy(bp);
215 error = biowait(bp);
216 pageio_done(bp);
217
218 /*CSTYLED*/
219 FBCOMMON(fbp, S_OTHER, 0, fberror = )
220
221 return (error ? error : fberror);
222 }
223