xref: /openbmc/linux/fs/bfs/inode.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2) 
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/fs.h>
13 #include <linux/smp_lock.h>
14 #include <linux/buffer_head.h>
15 #include <linux/vfs.h>
16 #include <asm/uaccess.h>
17 #include "bfs.h"
18 
19 MODULE_AUTHOR("Tigran A. Aivazian <tigran@veritas.com>");
20 MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
21 MODULE_LICENSE("GPL");
22 
23 #undef DEBUG
24 
25 #ifdef DEBUG
26 #define dprintf(x...)	printf(x)
27 #else
28 #define dprintf(x...)
29 #endif
30 
31 void dump_imap(const char *prefix, struct super_block * s);
32 
33 static void bfs_read_inode(struct inode * inode)
34 {
35 	unsigned long ino = inode->i_ino;
36 	struct bfs_inode * di;
37 	struct buffer_head * bh;
38 	int block, off;
39 
40 	if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
41 		printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
42 		make_bad_inode(inode);
43 		return;
44 	}
45 
46 	block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
47 	bh = sb_bread(inode->i_sb, block);
48 	if (!bh) {
49 		printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
50 		make_bad_inode(inode);
51 		return;
52 	}
53 
54 	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
55 	di = (struct bfs_inode *)bh->b_data + off;
56 
57 	inode->i_mode = 0x0000FFFF & di->i_mode;
58 	if (di->i_vtype == BFS_VDIR) {
59 		inode->i_mode |= S_IFDIR;
60 		inode->i_op = &bfs_dir_inops;
61 		inode->i_fop = &bfs_dir_operations;
62 	} else if (di->i_vtype == BFS_VREG) {
63 		inode->i_mode |= S_IFREG;
64 		inode->i_op = &bfs_file_inops;
65 		inode->i_fop = &bfs_file_operations;
66 		inode->i_mapping->a_ops = &bfs_aops;
67 	}
68 
69 	inode->i_uid = di->i_uid;
70 	inode->i_gid = di->i_gid;
71 	inode->i_nlink = di->i_nlink;
72 	inode->i_size = BFS_FILESIZE(di);
73 	inode->i_blocks = BFS_FILEBLOCKS(di);
74 	inode->i_blksize = PAGE_SIZE;
75 	inode->i_atime.tv_sec = di->i_atime;
76 	inode->i_mtime.tv_sec = di->i_mtime;
77 	inode->i_ctime.tv_sec = di->i_ctime;
78 	inode->i_atime.tv_nsec = 0;
79 	inode->i_mtime.tv_nsec = 0;
80 	inode->i_ctime.tv_nsec = 0;
81 	BFS_I(inode)->i_dsk_ino = di->i_ino; /* can be 0 so we store a copy */
82 	BFS_I(inode)->i_sblock = di->i_sblock;
83 	BFS_I(inode)->i_eblock = di->i_eblock;
84 
85 	brelse(bh);
86 }
87 
88 static int bfs_write_inode(struct inode * inode, int unused)
89 {
90 	unsigned long ino = inode->i_ino;
91 	struct bfs_inode * di;
92 	struct buffer_head * bh;
93 	int block, off;
94 
95 	if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
96 		printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
97 		return -EIO;
98 	}
99 
100 	lock_kernel();
101 	block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
102 	bh = sb_bread(inode->i_sb, block);
103 	if (!bh) {
104 		printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
105 		unlock_kernel();
106 		return -EIO;
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.tv_sec;
123 	di->i_mtime = inode->i_mtime.tv_sec;
124 	di->i_ctime = inode->i_ctime.tv_sec;
125 	di->i_sblock = BFS_I(inode)->i_sblock;
126 	di->i_eblock = BFS_I(inode)->i_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 	return 0;
133 }
134 
135 static void bfs_delete_inode(struct inode * inode)
136 {
137 	unsigned long ino = inode->i_ino;
138 	struct bfs_inode * di;
139 	struct buffer_head * bh;
140 	int block, off;
141 	struct super_block * s = inode->i_sb;
142 	struct bfs_sb_info * info = BFS_SB(s);
143 
144 	dprintf("ino=%08lx\n", inode->i_ino);
145 
146 	if (inode->i_ino < BFS_ROOT_INO || inode->i_ino > info->si_lasti) {
147 		printf("invalid ino=%08lx\n", inode->i_ino);
148 		return;
149 	}
150 
151 	inode->i_size = 0;
152 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
153 	lock_kernel();
154 	mark_inode_dirty(inode);
155 	block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
156 	bh = sb_bread(s, block);
157 	if (!bh) {
158 		printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
159 		unlock_kernel();
160 		return;
161 	}
162 	off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
163 	di = (struct bfs_inode *)bh->b_data + off;
164 	if (di->i_ino) {
165 		info->si_freeb += BFS_FILEBLOCKS(di);
166 		info->si_freei++;
167 		clear_bit(di->i_ino, info->si_imap);
168 		dump_imap("delete_inode", s);
169 	}
170 	di->i_ino = 0;
171 	di->i_sblock = 0;
172 	mark_buffer_dirty(bh);
173 	brelse(bh);
174 
175 	/* if this was the last file, make the previous
176 	   block "last files last block" even if there is no real file there,
177 	   saves us 1 gap */
178 	if (info->si_lf_eblk == BFS_I(inode)->i_eblock) {
179 		info->si_lf_eblk = BFS_I(inode)->i_sblock - 1;
180 		mark_buffer_dirty(info->si_sbh);
181 	}
182 	unlock_kernel();
183 	clear_inode(inode);
184 }
185 
186 static void bfs_put_super(struct super_block *s)
187 {
188 	struct bfs_sb_info *info = BFS_SB(s);
189 	brelse(info->si_sbh);
190 	kfree(info->si_imap);
191 	kfree(info);
192 	s->s_fs_info = NULL;
193 }
194 
195 static int bfs_statfs(struct super_block *s, struct kstatfs *buf)
196 {
197 	struct bfs_sb_info *info = BFS_SB(s);
198 	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
199 	buf->f_type = BFS_MAGIC;
200 	buf->f_bsize = s->s_blocksize;
201 	buf->f_blocks = info->si_blocks;
202 	buf->f_bfree = buf->f_bavail = info->si_freeb;
203 	buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
204 	buf->f_ffree = info->si_freei;
205 	buf->f_fsid.val[0] = (u32)id;
206 	buf->f_fsid.val[1] = (u32)(id >> 32);
207 	buf->f_namelen = BFS_NAMELEN;
208 	return 0;
209 }
210 
211 static void bfs_write_super(struct super_block *s)
212 {
213 	lock_kernel();
214 	if (!(s->s_flags & MS_RDONLY))
215 		mark_buffer_dirty(BFS_SB(s)->si_sbh);
216 	s->s_dirt = 0;
217 	unlock_kernel();
218 }
219 
220 static kmem_cache_t * bfs_inode_cachep;
221 
222 static struct inode *bfs_alloc_inode(struct super_block *sb)
223 {
224 	struct bfs_inode_info *bi;
225 	bi = kmem_cache_alloc(bfs_inode_cachep, SLAB_KERNEL);
226 	if (!bi)
227 		return NULL;
228 	return &bi->vfs_inode;
229 }
230 
231 static void bfs_destroy_inode(struct inode *inode)
232 {
233 	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
234 }
235 
236 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
237 {
238 	struct bfs_inode_info *bi = foo;
239 
240 	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
241 	    SLAB_CTOR_CONSTRUCTOR)
242 		inode_init_once(&bi->vfs_inode);
243 }
244 
245 static int init_inodecache(void)
246 {
247 	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
248 					     sizeof(struct bfs_inode_info),
249 					     0, SLAB_RECLAIM_ACCOUNT,
250 					     init_once, NULL);
251 	if (bfs_inode_cachep == NULL)
252 		return -ENOMEM;
253 	return 0;
254 }
255 
256 static void destroy_inodecache(void)
257 {
258 	if (kmem_cache_destroy(bfs_inode_cachep))
259 		printk(KERN_INFO "bfs_inode_cache: not all structures were freed\n");
260 }
261 
262 static struct super_operations bfs_sops = {
263 	.alloc_inode	= bfs_alloc_inode,
264 	.destroy_inode	= bfs_destroy_inode,
265 	.read_inode	= bfs_read_inode,
266 	.write_inode	= bfs_write_inode,
267 	.delete_inode	= bfs_delete_inode,
268 	.put_super	= bfs_put_super,
269 	.write_super	= bfs_write_super,
270 	.statfs		= bfs_statfs,
271 };
272 
273 void dump_imap(const char *prefix, struct super_block * s)
274 {
275 #if 0
276 	int i;
277 	char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
278 
279 	if (!tmpbuf)
280 		return;
281 	for (i=BFS_SB(s)->si_lasti; i>=0; i--) {
282 		if (i>PAGE_SIZE-100) break;
283 		if (test_bit(i, BFS_SB(s)->si_imap))
284 			strcat(tmpbuf, "1");
285 		else
286 			strcat(tmpbuf, "0");
287 	}
288 	printk(KERN_ERR "BFS-fs: %s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
289 	free_page((unsigned long)tmpbuf);
290 #endif
291 }
292 
293 static int bfs_fill_super(struct super_block *s, void *data, int silent)
294 {
295 	struct buffer_head * bh;
296 	struct bfs_super_block * bfs_sb;
297 	struct inode * inode;
298 	int i, imap_len;
299 	struct bfs_sb_info * info;
300 
301 	info = kmalloc(sizeof(*info), GFP_KERNEL);
302 	if (!info)
303 		return -ENOMEM;
304 	s->s_fs_info = info;
305 	memset(info, 0, sizeof(*info));
306 
307 	sb_set_blocksize(s, BFS_BSIZE);
308 
309 	bh = sb_bread(s, 0);
310 	if(!bh)
311 		goto out;
312 	bfs_sb = (struct bfs_super_block *)bh->b_data;
313 	if (bfs_sb->s_magic != BFS_MAGIC) {
314 		if (!silent)
315 			printf("No BFS filesystem on %s (magic=%08x)\n",
316 				s->s_id, bfs_sb->s_magic);
317 		goto out;
318 	}
319 	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
320 		printf("%s is unclean, continuing\n", s->s_id);
321 
322 	s->s_magic = BFS_MAGIC;
323 	info->si_bfs_sb = bfs_sb;
324 	info->si_sbh = bh;
325 	info->si_lasti = (bfs_sb->s_start - BFS_BSIZE)/sizeof(struct bfs_inode)
326 			+ BFS_ROOT_INO - 1;
327 
328 	imap_len = info->si_lasti/8 + 1;
329 	info->si_imap = kmalloc(imap_len, GFP_KERNEL);
330 	if (!info->si_imap)
331 		goto out;
332 	memset(info->si_imap, 0, imap_len);
333 	for (i=0; i<BFS_ROOT_INO; i++)
334 		set_bit(i, info->si_imap);
335 
336 	s->s_op = &bfs_sops;
337 	inode = iget(s, BFS_ROOT_INO);
338 	if (!inode) {
339 		kfree(info->si_imap);
340 		goto out;
341 	}
342 	s->s_root = d_alloc_root(inode);
343 	if (!s->s_root) {
344 		iput(inode);
345 		kfree(info->si_imap);
346 		goto out;
347 	}
348 
349 	info->si_blocks = (bfs_sb->s_end + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
350 	info->si_freeb = (bfs_sb->s_end + 1 - bfs_sb->s_start)>>BFS_BSIZE_BITS;
351 	info->si_freei = 0;
352 	info->si_lf_eblk = 0;
353 	info->si_lf_sblk = 0;
354 	info->si_lf_ioff = 0;
355 	for (i=BFS_ROOT_INO; i<=info->si_lasti; i++) {
356 		inode = iget(s,i);
357 		if (BFS_I(inode)->i_dsk_ino == 0)
358 			info->si_freei++;
359 		else {
360 			set_bit(i, info->si_imap);
361 			info->si_freeb -= inode->i_blocks;
362 			if (BFS_I(inode)->i_eblock > info->si_lf_eblk) {
363 				info->si_lf_eblk = BFS_I(inode)->i_eblock;
364 				info->si_lf_sblk = BFS_I(inode)->i_sblock;
365 				info->si_lf_ioff = BFS_INO2OFF(i);
366 			}
367 		}
368 		iput(inode);
369 	}
370 	if (!(s->s_flags & MS_RDONLY)) {
371 		mark_buffer_dirty(bh);
372 		s->s_dirt = 1;
373 	}
374 	dump_imap("read_super", s);
375 	return 0;
376 
377 out:
378 	brelse(bh);
379 	kfree(info);
380 	s->s_fs_info = NULL;
381 	return -EINVAL;
382 }
383 
384 static struct super_block *bfs_get_sb(struct file_system_type *fs_type,
385 	int flags, const char *dev_name, void *data)
386 {
387 	return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
388 }
389 
390 static struct file_system_type bfs_fs_type = {
391 	.owner		= THIS_MODULE,
392 	.name		= "bfs",
393 	.get_sb		= bfs_get_sb,
394 	.kill_sb	= kill_block_super,
395 	.fs_flags	= FS_REQUIRES_DEV,
396 };
397 
398 static int __init init_bfs_fs(void)
399 {
400 	int err = init_inodecache();
401 	if (err)
402 		goto out1;
403         err = register_filesystem(&bfs_fs_type);
404 	if (err)
405 		goto out;
406 	return 0;
407 out:
408 	destroy_inodecache();
409 out1:
410 	return err;
411 }
412 
413 static void __exit exit_bfs_fs(void)
414 {
415 	unregister_filesystem(&bfs_fs_type);
416 	destroy_inodecache();
417 }
418 
419 module_init(init_bfs_fs)
420 module_exit(exit_bfs_fs)
421