File: /usr/src/linux/fs/bfs/inode.c
1 /*
2 * fs/bfs/inode.c
3 * BFS superblock and inode operations.
4 * Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com>
5 * From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
6 */
7
8 #include <linux/module.h>
9 #include <linux/mm.h>
10 #include <linux/slab.h>
11 #include <linux/init.h>
12 #include <linux/locks.h>
13 #include <linux/bfs_fs.h>
14 #include <linux/smp_lock.h>
15
16 #include <asm/uaccess.h>
17
18 #include "bfs_defs.h"
19
20 MODULE_AUTHOR("Tigran A. Aivazian <tigran@veritas.com>");
21 MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
22 EXPORT_NO_SYMBOLS;
23
24 #undef DEBUG
25
26 #ifdef DEBUG
27 #define dprintf(x...) printf(x)
28 #else
29 #define dprintf(x...)
30 #endif
31
32 void dump_imap(const char *prefix, struct super_block * s);
33
34 static void bfs_read_inode(struct inode * inode)
35 {
36 unsigned long ino = inode->i_ino;
37 kdev_t dev = inode->i_dev;
38 struct bfs_inode * di;
39 struct buffer_head * bh;
40 int block, off;
41
42 if (ino < BFS_ROOT_INO || ino > inode->i_sb->su_lasti) {
43 printf("Bad inode number %s:%08lx\n", bdevname(dev), ino);
44 make_bad_inode(inode);
45 return;
46 }
47
48 block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
49 bh = bread(dev, block, BFS_BSIZE);
50 if (!bh) {
51 printf("Unable to read inode %s:%08lx\n", bdevname(dev), ino);
52 make_bad_inode(inode);
53 return;
54 }
55
56 off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
57 di = (struct bfs_inode *)bh->b_data + off;
58
59 inode->i_mode = 0x0000FFFF & di->i_mode;
60 if (di->i_vtype == BFS_VDIR) {
61 inode->i_mode |= S_IFDIR;
62 inode->i_op = &bfs_dir_inops;
63 inode->i_fop = &bfs_dir_operations;
64 } else if (di->i_vtype == BFS_VREG) {
65 inode->i_mode |= S_IFREG;
66 inode->i_op = &bfs_file_inops;
67 inode->i_fop = &bfs_file_operations;
68 inode->i_mapping->a_ops = &bfs_aops;
69 }
70
71 inode->i_uid = di->i_uid;
72 inode->i_gid = di->i_gid;
73 inode->i_nlink = di->i_nlink;
74 inode->i_size = BFS_FILESIZE(di);
75 inode->i_blocks = BFS_FILEBLOCKS(di);
76 inode->i_blksize = PAGE_SIZE;
77 inode->i_atime = di->i_atime;
78 inode->i_mtime = di->i_mtime;
79 inode->i_ctime = di->i_ctime;
80 inode->iu_dsk_ino = di->i_ino; /* can be 0 so we store a copy */
81 inode->iu_sblock = di->i_sblock;
82 inode->iu_eblock = di->i_eblock;
83
84 brelse(bh);
85 }
86
87 static void bfs_write_inode(struct inode * inode, int unused)
88 {
89 unsigned long ino = inode->i_ino;
90 kdev_t dev = inode->i_dev;
91 struct bfs_inode * di;
92 struct buffer_head * bh;
93 int block, off;
94
95 if (ino < BFS_ROOT_INO || ino > inode->i_sb->su_lasti) {
96 printf("Bad inode number %s:%08lx\n", bdevname(dev), ino);
97 return;
98 }
99
100 lock_kernel();
101 block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
102 bh = bread(dev, block, BFS_BSIZE);
103 if (!bh) {
104 printf("Unable to read inode %s:%08lx\n", bdevname(dev), ino);
105 unlock_kernel();
106 return;
107 }
108
109 off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
110 di = (struct bfs_inode *)bh->b_data + off;
111
112 if (inode->i_ino == BFS_ROOT_INO)
113 di->i_vtype = BFS_VDIR;
114 else
115 di->i_vtype = BFS_VREG;
116
117 di->i_ino = inode->i_ino;
118 di->i_mode = inode->i_mode;
119 di->i_uid = inode->i_uid;
120 di->i_gid = inode->i_gid;
121 di->i_nlink = inode->i_nlink;
122 di->i_atime = inode->i_atime;
123 di->i_mtime = inode->i_mtime;
124 di->i_ctime = inode->i_ctime;
125 di->i_sblock = inode->iu_sblock;
126 di->i_eblock = inode->iu_eblock;
127 di->i_eoffset = di->i_sblock * BFS_BSIZE + inode->i_size - 1;
128
129 mark_buffer_dirty(bh);
130 brelse(bh);
131 unlock_kernel();
132 }
133
134 static void bfs_delete_inode(struct inode * inode)
135 {
136 unsigned long ino = inode->i_ino;
137 kdev_t dev = inode->i_dev;
138 struct bfs_inode * di;
139 struct buffer_head * bh;
140 int block, off;
141 struct super_block * s = inode->i_sb;
142
143 dprintf("ino=%08lx\n", inode->i_ino);
144
145 if (inode->i_ino < BFS_ROOT_INO || inode->i_ino > inode->i_sb->su_lasti) {
146 printf("invalid ino=%08lx\n", inode->i_ino);
147 return;
148 }
149
150 inode->i_size = 0;
151 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
152 lock_kernel();
153 mark_inode_dirty(inode);
154 block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
155 bh = bread(dev, block, BFS_BSIZE);
156 if (!bh) {
157 printf("Unable to read inode %s:%08lx\n", bdevname(dev), ino);
158 unlock_kernel();
159 return;
160 }
161 off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
162 di = (struct bfs_inode *)bh->b_data + off;
163 if (di->i_ino) {
164 s->su_freeb += BFS_FILEBLOCKS(di);
165 s->su_freei++;
166 clear_bit(di->i_ino, s->su_imap);
167 dump_imap("delete_inode", s);
168 }
169 di->i_ino = 0;
170 di->i_sblock = 0;
171 mark_buffer_dirty(bh);
172 brelse(bh);
173
174 /* if this was the last file, make the previous
175 block "last files last block" even if there is no real file there,
176 saves us 1 gap */
177 if (s->su_lf_eblk == inode->iu_eblock) {
178 s->su_lf_eblk = inode->iu_sblock - 1;
179 mark_buffer_dirty(s->su_sbh);
180 }
181 unlock_kernel();
182 clear_inode(inode);
183 }
184
185 static void bfs_put_super(struct super_block *s)
186 {
187 brelse(s->su_sbh);
188 kfree(s->su_imap);
189 }
190
191 static int bfs_statfs(struct super_block *s, struct statfs *buf)
192 {
193 buf->f_type = BFS_MAGIC;
194 buf->f_bsize = s->s_blocksize;
195 buf->f_blocks = s->su_blocks;
196 buf->f_bfree = buf->f_bavail = s->su_freeb;
197 buf->f_files = s->su_lasti + 1 - BFS_ROOT_INO;
198 buf->f_ffree = s->su_freei;
199 buf->f_fsid.val[0] = kdev_t_to_nr(s->s_dev);
200 buf->f_namelen = BFS_NAMELEN;
201 return 0;
202 }
203
204 static void bfs_write_super(struct super_block *s)
205 {
206 if (!(s->s_flags & MS_RDONLY))
207 mark_buffer_dirty(s->su_sbh);
208 s->s_dirt = 0;
209 }
210
211 static struct super_operations bfs_sops = {
212 read_inode: bfs_read_inode,
213 write_inode: bfs_write_inode,
214 delete_inode: bfs_delete_inode,
215 put_super: bfs_put_super,
216 write_super: bfs_write_super,
217 statfs: bfs_statfs,
218 };
219
220 void dump_imap(const char *prefix, struct super_block * s)
221 {
222 #if 0
223 int i;
224 char *tmpbuf = (char *)get_free_page(GFP_KERNEL);
225
226 if (!tmpbuf)
227 return;
228 for (i=s->su_lasti; i>=0; i--) {
229 if (i>PAGE_SIZE-100) break;
230 if (test_bit(i, s->su_imap))
231 strcat(tmpbuf, "1");
232 else
233 strcat(tmpbuf, "0");
234 }
235 printk(KERN_ERR "BFS-fs: %s: lasti=%08lx <%s>\n", prefix, s->su_lasti, tmpbuf);
236 free_page((unsigned long)tmpbuf);
237 #endif
238 }
239
240 static struct super_block * bfs_read_super(struct super_block * s,
241 void * data, int silent)
242 {
243 kdev_t dev;
244 struct buffer_head * bh;
245 struct bfs_super_block * bfs_sb;
246 struct inode * inode;
247 int i, imap_len;
248
249 dev = s->s_dev;
250 set_blocksize(dev, BFS_BSIZE);
251 s->s_blocksize = BFS_BSIZE;
252 s->s_blocksize_bits = BFS_BSIZE_BITS;
253
254 bh = bread(dev, 0, BFS_BSIZE);
255 if(!bh)
256 goto out;
257 bfs_sb = (struct bfs_super_block *)bh->b_data;
258 if (bfs_sb->s_magic != BFS_MAGIC) {
259 if (!silent)
260 printf("No BFS filesystem on %s (magic=%08x)\n",
261 bdevname(dev), bfs_sb->s_magic);
262 goto out;
263 }
264 if (BFS_UNCLEAN(bfs_sb, s) && !silent)
265 printf("%s is unclean, continuing\n", bdevname(dev));
266
267 s->s_magic = BFS_MAGIC;
268 s->su_bfs_sb = bfs_sb;
269 s->su_sbh = bh;
270 s->su_lasti = (bfs_sb->s_start - BFS_BSIZE)/sizeof(struct bfs_inode)
271 + BFS_ROOT_INO - 1;
272
273 imap_len = s->su_lasti/8 + 1;
274 s->su_imap = kmalloc(imap_len, GFP_KERNEL);
275 if (!s->su_imap)
276 goto out;
277 memset(s->su_imap, 0, imap_len);
278 for (i=0; i<BFS_ROOT_INO; i++)
279 set_bit(i, s->su_imap);
280
281 s->s_op = &bfs_sops;
282 inode = iget(s, BFS_ROOT_INO);
283 if (!inode) {
284 kfree(s->su_imap);
285 goto out;
286 }
287 s->s_root = d_alloc_root(inode);
288 if (!s->s_root) {
289 iput(inode);
290 kfree(s->su_imap);
291 goto out;
292 }
293
294 s->su_blocks = (bfs_sb->s_end + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
295 s->su_freeb = (bfs_sb->s_end + 1 - bfs_sb->s_start)>>BFS_BSIZE_BITS;
296 s->su_freei = 0;
297 s->su_lf_eblk = 0;
298 s->su_lf_sblk = 0;
299 s->su_lf_ioff = 0;
300 for (i=BFS_ROOT_INO; i<=s->su_lasti; i++) {
301 inode = iget(s,i);
302 if (inode->iu_dsk_ino == 0)
303 s->su_freei++;
304 else {
305 set_bit(i, s->su_imap);
306 s->su_freeb -= inode->i_blocks;
307 if (inode->iu_eblock > s->su_lf_eblk) {
308 s->su_lf_eblk = inode->iu_eblock;
309 s->su_lf_sblk = inode->iu_sblock;
310 s->su_lf_ioff = BFS_INO2OFF(i);
311 }
312 }
313 iput(inode);
314 }
315 if (!(s->s_flags & MS_RDONLY)) {
316 mark_buffer_dirty(bh);
317 s->s_dirt = 1;
318 }
319 dump_imap("read_super", s);
320 return s;
321
322 out:
323 brelse(bh);
324 return NULL;
325 }
326
327 static DECLARE_FSTYPE_DEV(bfs_fs_type, "bfs", bfs_read_super);
328
329 static int __init init_bfs_fs(void)
330 {
331 return register_filesystem(&bfs_fs_type);
332 }
333
334 static void __exit exit_bfs_fs(void)
335 {
336 unregister_filesystem(&bfs_fs_type);
337 }
338
339 module_init(init_bfs_fs)
340 module_exit(exit_bfs_fs)
341