xref: /openbmc/linux/fs/bfs/inode.c (revision 643d1f7f)
1 /*
2  *	fs/bfs/inode.c
3  *	BFS superblock and inode operations.
4  *	Copyright (C) 1999-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
5  *	From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
6  *
7  *      Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 2005.
8  */
9 
10 #include <linux/module.h>
11 #include <linux/mm.h>
12 #include <linux/slab.h>
13 #include <linux/init.h>
14 #include <linux/fs.h>
15 #include <linux/smp_lock.h>
16 #include <linux/buffer_head.h>
17 #include <linux/vfs.h>
18 #include <asm/uaccess.h>
19 #include "bfs.h"
20 
21 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
22 MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
23 MODULE_LICENSE("GPL");
24 
25 #undef DEBUG
26 
27 #ifdef DEBUG
28 #define dprintf(x...)	printf(x)
29 #else
30 #define dprintf(x...)
31 #endif
32 
33 void dump_imap(const char *prefix, struct super_block *s);
34 
35 static void bfs_read_inode(struct inode *inode)
36 {
37 	unsigned long ino = inode->i_ino;
38 	struct bfs_inode *di;
39 	struct buffer_head *bh;
40 	int block, off;
41 
42 	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
43 		printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
44 		make_bad_inode(inode);
45 		return;
46 	}
47 
48 	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
49 	bh = sb_bread(inode->i_sb, block);
50 	if (!bh) {
51 		printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
52 									ino);
53 		make_bad_inode(inode);
54 		return;
55 	}
56 
57 	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
58 	di = (struct bfs_inode *)bh->b_data + off;
59 
60 	inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
61 	if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
62 		inode->i_mode |= S_IFDIR;
63 		inode->i_op = &bfs_dir_inops;
64 		inode->i_fop = &bfs_dir_operations;
65 	} else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
66 		inode->i_mode |= S_IFREG;
67 		inode->i_op = &bfs_file_inops;
68 		inode->i_fop = &bfs_file_operations;
69 		inode->i_mapping->a_ops = &bfs_aops;
70 	}
71 
72 	BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
73 	BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
74 	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
75 	inode->i_uid =  le32_to_cpu(di->i_uid);
76 	inode->i_gid =  le32_to_cpu(di->i_gid);
77 	inode->i_nlink =  le32_to_cpu(di->i_nlink);
78 	inode->i_size = BFS_FILESIZE(di);
79 	inode->i_blocks = BFS_FILEBLOCKS(di);
80 	inode->i_atime.tv_sec =  le32_to_cpu(di->i_atime);
81 	inode->i_mtime.tv_sec =  le32_to_cpu(di->i_mtime);
82 	inode->i_ctime.tv_sec =  le32_to_cpu(di->i_ctime);
83 	inode->i_atime.tv_nsec = 0;
84 	inode->i_mtime.tv_nsec = 0;
85 	inode->i_ctime.tv_nsec = 0;
86 
87 	brelse(bh);
88 }
89 
90 static int bfs_write_inode(struct inode *inode, int unused)
91 {
92 	unsigned int ino = (u16)inode->i_ino;
93         unsigned long i_sblock;
94 	struct bfs_inode *di;
95 	struct buffer_head *bh;
96 	int block, off;
97 
98         dprintf("ino=%08x\n", ino);
99 
100 	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
101 		printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
102 		return -EIO;
103 	}
104 
105 	lock_kernel();
106 	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
107 	bh = sb_bread(inode->i_sb, block);
108 	if (!bh) {
109 		printf("Unable to read inode %s:%08x\n",
110 				inode->i_sb->s_id, ino);
111 		unlock_kernel();
112 		return -EIO;
113 	}
114 
115 	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
116 	di = (struct bfs_inode *)bh->b_data + off;
117 
118 	if (ino == BFS_ROOT_INO)
119 		di->i_vtype = cpu_to_le32(BFS_VDIR);
120 	else
121 		di->i_vtype = cpu_to_le32(BFS_VREG);
122 
123 	di->i_ino = cpu_to_le16(ino);
124 	di->i_mode = cpu_to_le32(inode->i_mode);
125 	di->i_uid = cpu_to_le32(inode->i_uid);
126 	di->i_gid = cpu_to_le32(inode->i_gid);
127 	di->i_nlink = cpu_to_le32(inode->i_nlink);
128 	di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
129 	di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
130 	di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
131         i_sblock = BFS_I(inode)->i_sblock;
132 	di->i_sblock = cpu_to_le32(i_sblock);
133 	di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
134 	di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
135 
136 	mark_buffer_dirty(bh);
137 	brelse(bh);
138 	unlock_kernel();
139 	return 0;
140 }
141 
142 static void bfs_delete_inode(struct inode *inode)
143 {
144 	unsigned long ino = inode->i_ino;
145 	struct bfs_inode *di;
146 	struct buffer_head *bh;
147 	int block, off;
148 	struct super_block *s = inode->i_sb;
149 	struct bfs_sb_info *info = BFS_SB(s);
150 	struct bfs_inode_info *bi = BFS_I(inode);
151 
152 	dprintf("ino=%08lx\n", ino);
153 
154 	truncate_inode_pages(&inode->i_data, 0);
155 
156 	if ((ino < BFS_ROOT_INO) || (ino > info->si_lasti)) {
157 		printf("invalid ino=%08lx\n", ino);
158 		return;
159 	}
160 
161 	inode->i_size = 0;
162 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
163 	lock_kernel();
164 	mark_inode_dirty(inode);
165 
166 	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
167 	bh = sb_bread(s, block);
168 	if (!bh) {
169 		printf("Unable to read inode %s:%08lx\n",
170 					inode->i_sb->s_id, ino);
171 		unlock_kernel();
172 		return;
173 	}
174 	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
175 	di = (struct bfs_inode *)bh->b_data + off;
176 	memset((void *)di, 0, sizeof(struct bfs_inode));
177 	mark_buffer_dirty(bh);
178 	brelse(bh);
179 
180         if (bi->i_dsk_ino) {
181 		if (bi->i_sblock)
182 			info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
183 		info->si_freei++;
184 		clear_bit(ino, info->si_imap);
185 		dump_imap("delete_inode", s);
186         }
187 
188 	/*
189 	 * If this was the last file, make the previous block
190 	 * "last block of the last file" even if there is no
191 	 * real file there, saves us 1 gap.
192 	 */
193 	if (info->si_lf_eblk == bi->i_eblock) {
194 		info->si_lf_eblk = bi->i_sblock - 1;
195 		mark_buffer_dirty(info->si_sbh);
196 	}
197 	unlock_kernel();
198 	clear_inode(inode);
199 }
200 
201 static void bfs_put_super(struct super_block *s)
202 {
203 	struct bfs_sb_info *info = BFS_SB(s);
204 	brelse(info->si_sbh);
205 	kfree(info->si_imap);
206 	kfree(info);
207 	s->s_fs_info = NULL;
208 }
209 
210 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
211 {
212 	struct super_block *s = dentry->d_sb;
213 	struct bfs_sb_info *info = BFS_SB(s);
214 	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
215 	buf->f_type = BFS_MAGIC;
216 	buf->f_bsize = s->s_blocksize;
217 	buf->f_blocks = info->si_blocks;
218 	buf->f_bfree = buf->f_bavail = info->si_freeb;
219 	buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
220 	buf->f_ffree = info->si_freei;
221 	buf->f_fsid.val[0] = (u32)id;
222 	buf->f_fsid.val[1] = (u32)(id >> 32);
223 	buf->f_namelen = BFS_NAMELEN;
224 	return 0;
225 }
226 
227 static void bfs_write_super(struct super_block *s)
228 {
229 	lock_kernel();
230 	if (!(s->s_flags & MS_RDONLY))
231 		mark_buffer_dirty(BFS_SB(s)->si_sbh);
232 	s->s_dirt = 0;
233 	unlock_kernel();
234 }
235 
236 static struct kmem_cache *bfs_inode_cachep;
237 
238 static struct inode *bfs_alloc_inode(struct super_block *sb)
239 {
240 	struct bfs_inode_info *bi;
241 	bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
242 	if (!bi)
243 		return NULL;
244 	return &bi->vfs_inode;
245 }
246 
247 static void bfs_destroy_inode(struct inode *inode)
248 {
249 	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
250 }
251 
252 static void init_once(struct kmem_cache *cachep, void *foo)
253 {
254 	struct bfs_inode_info *bi = foo;
255 
256 	inode_init_once(&bi->vfs_inode);
257 }
258 
259 static int init_inodecache(void)
260 {
261 	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
262 					     sizeof(struct bfs_inode_info),
263 					     0, (SLAB_RECLAIM_ACCOUNT|
264 						SLAB_MEM_SPREAD),
265 					     init_once);
266 	if (bfs_inode_cachep == NULL)
267 		return -ENOMEM;
268 	return 0;
269 }
270 
271 static void destroy_inodecache(void)
272 {
273 	kmem_cache_destroy(bfs_inode_cachep);
274 }
275 
276 static const struct super_operations bfs_sops = {
277 	.alloc_inode	= bfs_alloc_inode,
278 	.destroy_inode	= bfs_destroy_inode,
279 	.read_inode	= bfs_read_inode,
280 	.write_inode	= bfs_write_inode,
281 	.delete_inode	= bfs_delete_inode,
282 	.put_super	= bfs_put_super,
283 	.write_super	= bfs_write_super,
284 	.statfs		= bfs_statfs,
285 };
286 
287 void dump_imap(const char *prefix, struct super_block *s)
288 {
289 #ifdef DEBUG
290 	int i;
291 	char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
292 
293 	if (!tmpbuf)
294 		return;
295 	for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
296 		if (i > PAGE_SIZE - 100) break;
297 		if (test_bit(i, BFS_SB(s)->si_imap))
298 			strcat(tmpbuf, "1");
299 		else
300 			strcat(tmpbuf, "0");
301 	}
302 	printf("BFS-fs: %s: lasti=%08lx <%s>\n",
303 				prefix, BFS_SB(s)->si_lasti, tmpbuf);
304 	free_page((unsigned long)tmpbuf);
305 #endif
306 }
307 
308 static int bfs_fill_super(struct super_block *s, void *data, int silent)
309 {
310 	struct buffer_head *bh;
311 	struct bfs_super_block *bfs_sb;
312 	struct inode *inode;
313 	unsigned i, imap_len;
314 	struct bfs_sb_info *info;
315 
316 	info = kzalloc(sizeof(*info), GFP_KERNEL);
317 	if (!info)
318 		return -ENOMEM;
319 	s->s_fs_info = info;
320 
321 	sb_set_blocksize(s, BFS_BSIZE);
322 
323 	bh = sb_bread(s, 0);
324 	if(!bh)
325 		goto out;
326 	bfs_sb = (struct bfs_super_block *)bh->b_data;
327 	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
328 		if (!silent)
329 			printf("No BFS filesystem on %s (magic=%08x)\n",
330 				s->s_id,  le32_to_cpu(bfs_sb->s_magic));
331 		goto out;
332 	}
333 	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
334 		printf("%s is unclean, continuing\n", s->s_id);
335 
336 	s->s_magic = BFS_MAGIC;
337 	info->si_sbh = bh;
338 	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
339 					sizeof(struct bfs_inode)
340 					+ BFS_ROOT_INO - 1;
341 	imap_len = (info->si_lasti / 8) + 1;
342 	info->si_imap = kzalloc(imap_len, GFP_KERNEL);
343 	if (!info->si_imap)
344 		goto out;
345 	for (i = 0; i < BFS_ROOT_INO; i++)
346 		set_bit(i, info->si_imap);
347 
348 	s->s_op = &bfs_sops;
349 	inode = iget(s, BFS_ROOT_INO);
350 	if (!inode) {
351 		kfree(info->si_imap);
352 		goto out;
353 	}
354 	s->s_root = d_alloc_root(inode);
355 	if (!s->s_root) {
356 		iput(inode);
357 		kfree(info->si_imap);
358 		goto out;
359 	}
360 
361 	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
362 	info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1
363 			- le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
364 	info->si_freei = 0;
365 	info->si_lf_eblk = 0;
366 	bh = NULL;
367 	for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
368 		struct bfs_inode *di;
369 		int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
370 		int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
371 		unsigned long sblock, eblock;
372 
373 		if (!off) {
374 			brelse(bh);
375 			bh = sb_bread(s, block);
376 		}
377 
378 		if (!bh)
379 			continue;
380 
381 		di = (struct bfs_inode *)bh->b_data + off;
382 
383 		if (!di->i_ino) {
384 			info->si_freei++;
385 			continue;
386 		}
387 		set_bit(i, info->si_imap);
388 		info->si_freeb -= BFS_FILEBLOCKS(di);
389 
390 		sblock =  le32_to_cpu(di->i_sblock);
391 		eblock =  le32_to_cpu(di->i_eblock);
392 		if (eblock > info->si_lf_eblk)
393 			info->si_lf_eblk = eblock;
394 	}
395 	brelse(bh);
396 	if (!(s->s_flags & MS_RDONLY)) {
397 		mark_buffer_dirty(info->si_sbh);
398 		s->s_dirt = 1;
399 	}
400 	dump_imap("read_super", s);
401 	return 0;
402 
403 out:
404 	brelse(bh);
405 	kfree(info);
406 	s->s_fs_info = NULL;
407 	return -EINVAL;
408 }
409 
410 static int bfs_get_sb(struct file_system_type *fs_type,
411 	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
412 {
413 	return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt);
414 }
415 
416 static struct file_system_type bfs_fs_type = {
417 	.owner		= THIS_MODULE,
418 	.name		= "bfs",
419 	.get_sb		= bfs_get_sb,
420 	.kill_sb	= kill_block_super,
421 	.fs_flags	= FS_REQUIRES_DEV,
422 };
423 
424 static int __init init_bfs_fs(void)
425 {
426 	int err = init_inodecache();
427 	if (err)
428 		goto out1;
429         err = register_filesystem(&bfs_fs_type);
430 	if (err)
431 		goto out;
432 	return 0;
433 out:
434 	destroy_inodecache();
435 out1:
436 	return err;
437 }
438 
439 static void __exit exit_bfs_fs(void)
440 {
441 	unregister_filesystem(&bfs_fs_type);
442 	destroy_inodecache();
443 }
444 
445 module_init(init_bfs_fs)
446 module_exit(exit_bfs_fs)
447