xref: /openbmc/linux/fs/bfs/inode.c (revision 87c2ce3b)
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  *      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 A. Aivazian <tigran@veritas.com>");
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, 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 &  le32_to_cpu(di->i_mode);
60 	if (le32_to_cpu(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 (le32_to_cpu(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 	BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
72 	BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
73 	inode->i_uid =  le32_to_cpu(di->i_uid);
74 	inode->i_gid =  le32_to_cpu(di->i_gid);
75 	inode->i_nlink =  le32_to_cpu(di->i_nlink);
76 	inode->i_size = BFS_FILESIZE(di);
77 	inode->i_blocks = BFS_FILEBLOCKS(di);
78         if (inode->i_size || inode->i_blocks) dprintf("Registered inode with %lld size, %ld blocks\n", inode->i_size, inode->i_blocks);
79 	inode->i_blksize = PAGE_SIZE;
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 	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); /* can be 0 so we store a copy */
87 
88 	brelse(bh);
89 }
90 
91 static int bfs_write_inode(struct inode * inode, int unused)
92 {
93 	unsigned int ino = (u16)inode->i_ino;
94         unsigned long i_sblock;
95 	struct bfs_inode * di;
96 	struct buffer_head * bh;
97 	int block, off;
98 
99         dprintf("ino=%08x\n", ino);
100 
101 	if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
102 		printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
103 		return -EIO;
104 	}
105 
106 	lock_kernel();
107 	block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
108 	bh = sb_bread(inode->i_sb, block);
109 	if (!bh) {
110 		printf("Unable to read inode %s:%08x\n", 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         dprintf("Written ino=%d into %d:%d\n",le16_to_cpu(di->i_ino),block,off);
138 	brelse(bh);
139 	unlock_kernel();
140 	return 0;
141 }
142 
143 static void bfs_delete_inode(struct inode * inode)
144 {
145 	unsigned long ino = inode->i_ino;
146 	struct bfs_inode * di;
147 	struct buffer_head * bh;
148 	int block, off;
149 	struct super_block * s = inode->i_sb;
150 	struct bfs_sb_info * info = BFS_SB(s);
151 	struct bfs_inode_info * bi = BFS_I(inode);
152 
153 	dprintf("ino=%08lx\n", ino);
154 
155 	truncate_inode_pages(&inode->i_data, 0);
156 
157 	if (ino < BFS_ROOT_INO || ino > info->si_lasti) {
158 		printf("invalid ino=%08lx\n", ino);
159 		return;
160 	}
161 
162 	inode->i_size = 0;
163 	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
164 	lock_kernel();
165 	mark_inode_dirty(inode);
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", inode->i_sb->s_id, ino);
170 		unlock_kernel();
171 		return;
172 	}
173 	off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
174 	di = (struct bfs_inode *) bh->b_data + off;
175         if (bi->i_dsk_ino) {
176 		info->si_freeb += 1 + bi->i_eblock - bi->i_sblock;
177 		info->si_freei++;
178 		clear_bit(ino, info->si_imap);
179 		dump_imap("delete_inode", s);
180         }
181 	di->i_ino = 0;
182 	di->i_sblock = 0;
183 	mark_buffer_dirty(bh);
184 	brelse(bh);
185 
186 	/* if this was the last file, make the previous
187 	   block "last files last block" even if there is no real file there,
188 	   saves us 1 gap */
189 	if (info->si_lf_eblk == BFS_I(inode)->i_eblock) {
190 		info->si_lf_eblk = BFS_I(inode)->i_sblock - 1;
191 		mark_buffer_dirty(info->si_sbh);
192 	}
193 	unlock_kernel();
194 	clear_inode(inode);
195 }
196 
197 static void bfs_put_super(struct super_block *s)
198 {
199 	struct bfs_sb_info *info = BFS_SB(s);
200 	brelse(info->si_sbh);
201 	kfree(info->si_imap);
202 	kfree(info);
203 	s->s_fs_info = NULL;
204 }
205 
206 static int bfs_statfs(struct super_block *s, struct kstatfs *buf)
207 {
208 	struct bfs_sb_info *info = BFS_SB(s);
209 	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
210 	buf->f_type = BFS_MAGIC;
211 	buf->f_bsize = s->s_blocksize;
212 	buf->f_blocks = info->si_blocks;
213 	buf->f_bfree = buf->f_bavail = info->si_freeb;
214 	buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
215 	buf->f_ffree = info->si_freei;
216 	buf->f_fsid.val[0] = (u32)id;
217 	buf->f_fsid.val[1] = (u32)(id >> 32);
218 	buf->f_namelen = BFS_NAMELEN;
219 	return 0;
220 }
221 
222 static void bfs_write_super(struct super_block *s)
223 {
224 	lock_kernel();
225 	if (!(s->s_flags & MS_RDONLY))
226 		mark_buffer_dirty(BFS_SB(s)->si_sbh);
227 	s->s_dirt = 0;
228 	unlock_kernel();
229 }
230 
231 static kmem_cache_t * bfs_inode_cachep;
232 
233 static struct inode *bfs_alloc_inode(struct super_block *sb)
234 {
235 	struct bfs_inode_info *bi;
236 	bi = kmem_cache_alloc(bfs_inode_cachep, SLAB_KERNEL);
237 	if (!bi)
238 		return NULL;
239 	return &bi->vfs_inode;
240 }
241 
242 static void bfs_destroy_inode(struct inode *inode)
243 {
244 	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
245 }
246 
247 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
248 {
249 	struct bfs_inode_info *bi = foo;
250 
251 	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
252 	    SLAB_CTOR_CONSTRUCTOR)
253 		inode_init_once(&bi->vfs_inode);
254 }
255 
256 static int init_inodecache(void)
257 {
258 	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
259 					     sizeof(struct bfs_inode_info),
260 					     0, SLAB_RECLAIM_ACCOUNT,
261 					     init_once, NULL);
262 	if (bfs_inode_cachep == NULL)
263 		return -ENOMEM;
264 	return 0;
265 }
266 
267 static void destroy_inodecache(void)
268 {
269 	if (kmem_cache_destroy(bfs_inode_cachep))
270 		printk(KERN_INFO "bfs_inode_cache: not all structures were freed\n");
271 }
272 
273 static struct super_operations bfs_sops = {
274 	.alloc_inode	= bfs_alloc_inode,
275 	.destroy_inode	= bfs_destroy_inode,
276 	.read_inode	= bfs_read_inode,
277 	.write_inode	= bfs_write_inode,
278 	.delete_inode	= bfs_delete_inode,
279 	.put_super	= bfs_put_super,
280 	.write_super	= bfs_write_super,
281 	.statfs		= bfs_statfs,
282 };
283 
284 void dump_imap(const char *prefix, struct super_block * s)
285 {
286 #ifdef DEBUG
287 	int i;
288 	char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
289 
290 	if (!tmpbuf)
291 		return;
292 	for (i=BFS_SB(s)->si_lasti; i>=0; i--) {
293 		if (i > PAGE_SIZE-100) break;
294 		if (test_bit(i, BFS_SB(s)->si_imap))
295 			strcat(tmpbuf, "1");
296 		else
297 			strcat(tmpbuf, "0");
298 	}
299 	printk(KERN_ERR "BFS-fs: %s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
300 	free_page((unsigned long)tmpbuf);
301 #endif
302 }
303 
304 static int bfs_fill_super(struct super_block *s, void *data, int silent)
305 {
306 	struct buffer_head * bh;
307 	struct bfs_super_block * bfs_sb;
308 	struct inode * inode;
309 	unsigned i, imap_len;
310 	struct bfs_sb_info * info;
311 
312 	info = kmalloc(sizeof(*info), GFP_KERNEL);
313 	if (!info)
314 		return -ENOMEM;
315 	s->s_fs_info = info;
316 	memset(info, 0, sizeof(*info));
317 
318 	sb_set_blocksize(s, BFS_BSIZE);
319 
320 	bh = sb_bread(s, 0);
321 	if(!bh)
322 		goto out;
323 	bfs_sb = (struct bfs_super_block *)bh->b_data;
324 	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
325 		if (!silent)
326 			printf("No BFS filesystem on %s (magic=%08x)\n",
327 				s->s_id,  le32_to_cpu(bfs_sb->s_magic));
328 		goto out;
329 	}
330 	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
331 		printf("%s is unclean, continuing\n", s->s_id);
332 
333 	s->s_magic = BFS_MAGIC;
334 	info->si_sbh = bh;
335 	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE)/sizeof(struct bfs_inode)
336 			+ BFS_ROOT_INO - 1;
337 
338 	imap_len = info->si_lasti/8 + 1;
339 	info->si_imap = kmalloc(imap_len, GFP_KERNEL);
340 	if (!info->si_imap)
341 		goto out;
342 	memset(info->si_imap, 0, imap_len);
343 	for (i=0; i<BFS_ROOT_INO; i++)
344 		set_bit(i, info->si_imap);
345 
346 	s->s_op = &bfs_sops;
347 	inode = iget(s, BFS_ROOT_INO);
348 	if (!inode) {
349 		kfree(info->si_imap);
350 		goto out;
351 	}
352 	s->s_root = d_alloc_root(inode);
353 	if (!s->s_root) {
354 		iput(inode);
355 		kfree(info->si_imap);
356 		goto out;
357 	}
358 
359 	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
360 	info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 -  le32_to_cpu(bfs_sb->s_start))>>BFS_BSIZE_BITS;
361 	info->si_freei = 0;
362 	info->si_lf_eblk = 0;
363 	info->si_lf_sblk = 0;
364 	info->si_lf_ioff = 0;
365 	bh = NULL;
366 	for (i=BFS_ROOT_INO; i<=info->si_lasti; i++) {
367 		struct bfs_inode *di;
368 		int block = (i - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
369 		int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
370 		unsigned long sblock, eblock;
371 
372 		if (!off) {
373 			brelse(bh);
374 			bh = sb_bread(s, block);
375 		}
376 
377 		if (!bh)
378 			continue;
379 
380 		di = (struct bfs_inode *)bh->b_data + off;
381 
382 		if (!di->i_ino) {
383 			info->si_freei++;
384 			continue;
385 		}
386 		set_bit(i, info->si_imap);
387 		info->si_freeb -= BFS_FILEBLOCKS(di);
388 
389 		sblock =  le32_to_cpu(di->i_sblock);
390 		eblock =  le32_to_cpu(di->i_eblock);
391 		if (eblock > info->si_lf_eblk) {
392 			info->si_lf_eblk = eblock;
393 			info->si_lf_sblk = sblock;
394 			info->si_lf_ioff = BFS_INO2OFF(i);
395 		}
396 	}
397 	brelse(bh);
398 	if (!(s->s_flags & MS_RDONLY)) {
399 		mark_buffer_dirty(info->si_sbh);
400 		s->s_dirt = 1;
401 	}
402 	dump_imap("read_super", s);
403 	return 0;
404 
405 out:
406 	brelse(bh);
407 	kfree(info);
408 	s->s_fs_info = NULL;
409 	return -EINVAL;
410 }
411 
412 static struct super_block *bfs_get_sb(struct file_system_type *fs_type,
413 	int flags, const char *dev_name, void *data)
414 {
415 	return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
416 }
417 
418 static struct file_system_type bfs_fs_type = {
419 	.owner		= THIS_MODULE,
420 	.name		= "bfs",
421 	.get_sb		= bfs_get_sb,
422 	.kill_sb	= kill_block_super,
423 	.fs_flags	= FS_REQUIRES_DEV,
424 };
425 
426 static int __init init_bfs_fs(void)
427 {
428 	int err = init_inodecache();
429 	if (err)
430 		goto out1;
431         err = register_filesystem(&bfs_fs_type);
432 	if (err)
433 		goto out;
434 	return 0;
435 out:
436 	destroy_inodecache();
437 out1:
438 	return err;
439 }
440 
441 static void __exit exit_bfs_fs(void)
442 {
443 	unregister_filesystem(&bfs_fs_type);
444 	destroy_inodecache();
445 }
446 
447 module_init(init_bfs_fs)
448 module_exit(exit_bfs_fs)
449