Annotation of sys/arch/mvme88k/stand/bootst/rawfs.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: rawfs.c,v 1.4 2006/05/16 22:52:09 miod Exp $ */
2:
3: /*
4: * Copyright (c) 1995 Gordon W. Ross
5: * All rights reserved.
6: *
7: * Redistribution and use in source and binary forms, with or without
8: * modification, are permitted provided that the following conditions
9: * are met:
10: * 1. Redistributions of source code must retain the above copyright
11: * notice, this list of conditions and the following disclaimer.
12: * 2. Redistributions in binary form must reproduce the above copyright
13: * notice, this list of conditions and the following disclaimer in the
14: * documentation and/or other materials provided with the distribution.
15: * 3. The name of the author may not be used to endorse or promote products
16: * derived from this software without specific prior written permission.
17: * 4. All advertising materials mentioning features or use of this software
18: * must display the following acknowledgement:
19: * This product includes software developed by Gordon W. Ross
20: *
21: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31: */
32:
33: /*
34: * Raw file system - for stream devices like tapes.
35: * No random access, only sequential read allowed.
36: * This exists only to allow upper level code to be
37: * shielded from the fact that the device must be
38: * read only with whole block position and size.
39: */
40:
41: #include <sys/param.h>
42: #include <stand.h>
43: #include <rawfs.h>
44:
45: #define RAWFS_BSIZE 512
46:
47: /*
48: * In-core open file.
49: */
50: struct cfile {
51: daddr_t fs_nextblk; /* block number to read next */
52: int fs_len; /* amount left in f_buf */
53: char * fs_ptr; /* read pointer into f_buf */
54: char fs_buf[RAWFS_BSIZE];
55: };
56:
57: static int
58: rawfs_get_block(struct open_file *);
59:
60: int rawfs_open(path, f)
61: char *path;
62: struct open_file *f;
63: {
64: struct cfile *fs;
65:
66: /*
67: * The actual PROM driver has already been opened.
68: * Just allocate the I/O buffer, etc.
69: */
70: fs = alloc(sizeof(struct cfile));
71: fs->fs_nextblk = 0;
72: fs->fs_len = 0;
73: fs->fs_ptr = fs->fs_buf;
74:
75: f->f_fsdata = fs;
76: return (0);
77: }
78:
79: int rawfs_close(f)
80: struct open_file *f;
81: {
82: struct cfile *fs;
83:
84: fs = (struct cfile *) f->f_fsdata;
85: f->f_fsdata = (void *)0;
86:
87: if (fs != (struct cfile *)0)
88: free(fs, sizeof(*fs));
89:
90: return (0);
91: }
92:
93: int rawfs_read(f, start, size, resid)
94: struct open_file *f;
95: void *start;
96: size_t size;
97: size_t *resid;
98: {
99: struct cfile *fs = (struct cfile *)f->f_fsdata;
100: char *addr = start;
101: int error = 0;
102: size_t csize;
103:
104: while (size != 0) {
105:
106: if (fs->fs_len == 0)
107: if ((error = rawfs_get_block(f)) != 0)
108: break;
109:
110: if (fs->fs_len <= 0)
111: break; /* EOF */
112:
113: csize = size;
114: if (csize > fs->fs_len)
115: csize = fs->fs_len;
116:
117: bcopy(fs->fs_ptr, addr, csize);
118: fs->fs_ptr += csize;
119: fs->fs_len -= csize;
120: addr += csize;
121: size -= csize;
122: }
123: if (resid)
124: *resid = size;
125: return (error);
126: }
127:
128: int rawfs_write(f, start, size, resid)
129: struct open_file *f;
130: void *start;
131: size_t size;
132: size_t *resid; /* out */
133: {
134: return (EROFS);
135: }
136:
137: off_t rawfs_seek(f, offset, where)
138: struct open_file *f;
139: off_t offset;
140: int where;
141: {
142: return (EFTYPE);
143: }
144:
145: int rawfs_stat(f, sb)
146: struct open_file *f;
147: struct stat *sb;
148: {
149: return (EFTYPE);
150: }
151:
152:
153: /*
154: * Read a block from the underlying stream device
155: * (In our case, a tape drive.)
156: */
157: static int
158: rawfs_get_block(f)
159: struct open_file *f;
160: {
161: struct cfile *fs;
162: int error;
163: size_t len;
164:
165: fs = (struct cfile *)f->f_fsdata;
166: fs->fs_ptr = fs->fs_buf;
167:
168: twiddle();
169: error = f->f_dev->dv_strategy(f->f_devdata, F_READ,
170: fs->fs_nextblk, RAWFS_BSIZE, fs->fs_buf, &len);
171:
172: if (!error) {
173: fs->fs_len = len;
174: fs->fs_nextblk += (RAWFS_BSIZE / DEV_BSIZE);
175: }
176:
177: return (error);
178: }
179:
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