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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *	fs/bfs/inode.c
  4 *	BFS superblock and inode operations.
  5 *	Copyright (C) 1999-2018 Tigran Aivazian <aivazian.tigran@gmail.com>
  6 *	From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
  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/buffer_head.h>
 16#include <linux/vfs.h>
 17#include <linux/writeback.h>
 18#include <linux/uio.h>
 19#include <linux/uaccess.h>
 20#include "bfs.h"
 21
 22MODULE_AUTHOR("Tigran Aivazian <aivazian.tigran@gmail.com>");
 23MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
 24MODULE_LICENSE("GPL");
 25
 26#undef DEBUG
 27
 28#ifdef DEBUG
 29#define dprintf(x...)	printf(x)
 30#else
 31#define dprintf(x...)
 32#endif
 33
 34struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
 35{
 36	struct bfs_inode *di;
 37	struct inode *inode;
 38	struct buffer_head *bh;
 39	int block, off;
 40
 41	inode = iget_locked(sb, ino);
 42	if (!inode)
 43		return ERR_PTR(-ENOMEM);
 44	if (!(inode->i_state & I_NEW))
 45		return inode;
 46
 47	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
 48		printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
 49		goto error;
 50	}
 51
 52	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
 53	bh = sb_bread(inode->i_sb, block);
 54	if (!bh) {
 55		printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
 56									ino);
 57		goto error;
 58	}
 59
 60	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
 61	di = (struct bfs_inode *)bh->b_data + off;
 62
 63	inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
 64	if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
 65		inode->i_mode |= S_IFDIR;
 66		inode->i_op = &bfs_dir_inops;
 67		inode->i_fop = &bfs_dir_operations;
 68	} else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
 69		inode->i_mode |= S_IFREG;
 70		inode->i_op = &bfs_file_inops;
 71		inode->i_fop = &bfs_file_operations;
 72		inode->i_mapping->a_ops = &bfs_aops;
 73	}
 74
 75	BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
 76	BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
 77	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
 78	i_uid_write(inode, le32_to_cpu(di->i_uid));
 79	i_gid_write(inode,  le32_to_cpu(di->i_gid));
 80	set_nlink(inode, le32_to_cpu(di->i_nlink));
 81	inode->i_size = BFS_FILESIZE(di);
 82	inode->i_blocks = BFS_FILEBLOCKS(di);
 83	inode_set_atime(inode, le32_to_cpu(di->i_atime), 0);
 84	inode_set_mtime(inode, le32_to_cpu(di->i_mtime), 0);
 85	inode_set_ctime(inode, le32_to_cpu(di->i_ctime), 0);
 
 
 
 86
 87	brelse(bh);
 88	unlock_new_inode(inode);
 89	return inode;
 90
 91error:
 92	iget_failed(inode);
 93	return ERR_PTR(-EIO);
 94}
 95
 96static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p)
 97{
 98	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) {
 99		printf("Bad inode number %s:%08x\n", sb->s_id, ino);
100		return ERR_PTR(-EIO);
101	}
102
103	ino -= BFS_ROOT_INO;
104
105	*p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK);
106	if (!*p) {
107		printf("Unable to read inode %s:%08x\n", sb->s_id, ino);
108		return ERR_PTR(-EIO);
109	}
110
111	return (struct bfs_inode *)(*p)->b_data +  ino % BFS_INODES_PER_BLOCK;
112}
113
114static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc)
115{
116	struct bfs_sb_info *info = BFS_SB(inode->i_sb);
117	unsigned int ino = (u16)inode->i_ino;
118	unsigned long i_sblock;
119	struct bfs_inode *di;
120	struct buffer_head *bh;
121	int err = 0;
122
123	dprintf("ino=%08x\n", ino);
124
125	di = find_inode(inode->i_sb, ino, &bh);
126	if (IS_ERR(di))
127		return PTR_ERR(di);
128
129	mutex_lock(&info->bfs_lock);
130
131	if (ino == BFS_ROOT_INO)
132		di->i_vtype = cpu_to_le32(BFS_VDIR);
133	else
134		di->i_vtype = cpu_to_le32(BFS_VREG);
135
136	di->i_ino = cpu_to_le16(ino);
137	di->i_mode = cpu_to_le32(inode->i_mode);
138	di->i_uid = cpu_to_le32(i_uid_read(inode));
139	di->i_gid = cpu_to_le32(i_gid_read(inode));
140	di->i_nlink = cpu_to_le32(inode->i_nlink);
141	di->i_atime = cpu_to_le32(inode_get_atime_sec(inode));
142	di->i_mtime = cpu_to_le32(inode_get_mtime_sec(inode));
143	di->i_ctime = cpu_to_le32(inode_get_ctime_sec(inode));
144	i_sblock = BFS_I(inode)->i_sblock;
145	di->i_sblock = cpu_to_le32(i_sblock);
146	di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
147	di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
148
149	mark_buffer_dirty(bh);
150	if (wbc->sync_mode == WB_SYNC_ALL) {
151		sync_dirty_buffer(bh);
152		if (buffer_req(bh) && !buffer_uptodate(bh))
153			err = -EIO;
154	}
155	brelse(bh);
156	mutex_unlock(&info->bfs_lock);
157	return err;
158}
159
160static void bfs_evict_inode(struct inode *inode)
161{
162	unsigned long ino = inode->i_ino;
163	struct bfs_inode *di;
164	struct buffer_head *bh;
165	struct super_block *s = inode->i_sb;
166	struct bfs_sb_info *info = BFS_SB(s);
167	struct bfs_inode_info *bi = BFS_I(inode);
168
169	dprintf("ino=%08lx\n", ino);
170
171	truncate_inode_pages_final(&inode->i_data);
172	invalidate_inode_buffers(inode);
173	clear_inode(inode);
174
175	if (inode->i_nlink)
176		return;
177
178	di = find_inode(s, inode->i_ino, &bh);
179	if (IS_ERR(di))
180		return;
181
182	mutex_lock(&info->bfs_lock);
183	/* clear on-disk inode */
184	memset(di, 0, sizeof(struct bfs_inode));
185	mark_buffer_dirty(bh);
186	brelse(bh);
187
188	if (bi->i_dsk_ino) {
189		if (bi->i_sblock)
190			info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
191		info->si_freei++;
192		clear_bit(ino, info->si_imap);
193		bfs_dump_imap("evict_inode", s);
194	}
195
196	/*
197	 * If this was the last file, make the previous block
198	 * "last block of the last file" even if there is no
199	 * real file there, saves us 1 gap.
200	 */
201	if (info->si_lf_eblk == bi->i_eblock)
202		info->si_lf_eblk = bi->i_sblock - 1;
203	mutex_unlock(&info->bfs_lock);
204}
205
206static void bfs_put_super(struct super_block *s)
207{
208	struct bfs_sb_info *info = BFS_SB(s);
209
210	if (!info)
211		return;
212
213	mutex_destroy(&info->bfs_lock);
 
214	kfree(info);
215	s->s_fs_info = NULL;
216}
217
218static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
219{
220	struct super_block *s = dentry->d_sb;
221	struct bfs_sb_info *info = BFS_SB(s);
222	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
223	buf->f_type = BFS_MAGIC;
224	buf->f_bsize = s->s_blocksize;
225	buf->f_blocks = info->si_blocks;
226	buf->f_bfree = buf->f_bavail = info->si_freeb;
227	buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
228	buf->f_ffree = info->si_freei;
229	buf->f_fsid = u64_to_fsid(id);
 
230	buf->f_namelen = BFS_NAMELEN;
231	return 0;
232}
233
234static struct kmem_cache *bfs_inode_cachep;
235
236static struct inode *bfs_alloc_inode(struct super_block *sb)
237{
238	struct bfs_inode_info *bi;
239	bi = alloc_inode_sb(sb, bfs_inode_cachep, GFP_KERNEL);
240	if (!bi)
241		return NULL;
242	return &bi->vfs_inode;
243}
244
245static void bfs_free_inode(struct inode *inode)
246{
 
247	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
248}
249
 
 
 
 
 
250static void init_once(void *foo)
251{
252	struct bfs_inode_info *bi = foo;
253
254	inode_init_once(&bi->vfs_inode);
255}
256
257static int __init init_inodecache(void)
258{
259	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
260					     sizeof(struct bfs_inode_info),
261					     0, (SLAB_RECLAIM_ACCOUNT|
262						SLAB_ACCOUNT),
263					     init_once);
264	if (bfs_inode_cachep == NULL)
265		return -ENOMEM;
266	return 0;
267}
268
269static void destroy_inodecache(void)
270{
271	/*
272	 * Make sure all delayed rcu free inodes are flushed before we
273	 * destroy cache.
274	 */
275	rcu_barrier();
276	kmem_cache_destroy(bfs_inode_cachep);
277}
278
279static const struct super_operations bfs_sops = {
280	.alloc_inode	= bfs_alloc_inode,
281	.free_inode	= bfs_free_inode,
282	.write_inode	= bfs_write_inode,
283	.evict_inode	= bfs_evict_inode,
284	.put_super	= bfs_put_super,
285	.statfs		= bfs_statfs,
286};
287
288void bfs_dump_imap(const char *prefix, struct super_block *s)
289{
290#ifdef DEBUG
291	int i;
292	char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
293
294	if (!tmpbuf)
295		return;
296	for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
297		if (i > PAGE_SIZE - 100) break;
298		if (test_bit(i, BFS_SB(s)->si_imap))
299			strcat(tmpbuf, "1");
300		else
301			strcat(tmpbuf, "0");
302	}
303	printf("%s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
 
304	free_page((unsigned long)tmpbuf);
305#endif
306}
307
308static int bfs_fill_super(struct super_block *s, void *data, int silent)
309{
310	struct buffer_head *bh, *sbh;
311	struct bfs_super_block *bfs_sb;
312	struct inode *inode;
313	unsigned i;
314	struct bfs_sb_info *info;
315	int ret = -EINVAL;
316	unsigned long i_sblock, i_eblock, i_eoff, s_size;
317
318	info = kzalloc(sizeof(*info), GFP_KERNEL);
319	if (!info)
320		return -ENOMEM;
321	mutex_init(&info->bfs_lock);
322	s->s_fs_info = info;
323	s->s_time_min = 0;
324	s->s_time_max = U32_MAX;
325
326	sb_set_blocksize(s, BFS_BSIZE);
327
328	sbh = sb_bread(s, 0);
329	if (!sbh)
330		goto out;
331	bfs_sb = (struct bfs_super_block *)sbh->b_data;
332	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
333		if (!silent)
334			printf("No BFS filesystem on %s (magic=%08x)\n", s->s_id,  le32_to_cpu(bfs_sb->s_magic));
 
335		goto out1;
336	}
337	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
338		printf("%s is unclean, continuing\n", s->s_id);
339
340	s->s_magic = BFS_MAGIC;
341
342	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) ||
343	    le32_to_cpu(bfs_sb->s_start) < sizeof(struct bfs_super_block) + sizeof(struct bfs_dirent)) {
344		printf("Superblock is corrupted on %s\n", s->s_id);
345		goto out1;
346	}
347
348	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / sizeof(struct bfs_inode) + BFS_ROOT_INO - 1;
349	if (info->si_lasti == BFS_MAX_LASTI)
350		printf("NOTE: filesystem %s was created with 512 inodes, the real maximum is 511, mounting anyway\n", s->s_id);
351	else if (info->si_lasti > BFS_MAX_LASTI) {
352		printf("Impossible last inode number %lu > %d on %s\n", info->si_lasti, BFS_MAX_LASTI, s->s_id);
 
353		goto out1;
354	}
355	for (i = 0; i < BFS_ROOT_INO; i++)
356		set_bit(i, info->si_imap);
357
358	s->s_op = &bfs_sops;
359	inode = bfs_iget(s, BFS_ROOT_INO);
360	if (IS_ERR(inode)) {
361		ret = PTR_ERR(inode);
362		goto out1;
363	}
364	s->s_root = d_make_root(inode);
365	if (!s->s_root) {
366		ret = -ENOMEM;
367		goto out1;
368	}
369
370	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
371	info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
 
372	info->si_freei = 0;
373	info->si_lf_eblk = 0;
374
375	/* can we read the last block? */
376	bh = sb_bread(s, info->si_blocks - 1);
377	if (!bh) {
378		printf("Last block not available on %s: %lu\n", s->s_id, info->si_blocks - 1);
379		ret = -EIO;
380		goto out2;
381	}
382	brelse(bh);
383
384	bh = NULL;
385	for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
386		struct bfs_inode *di;
387		int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
388		int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
389		unsigned long eblock;
390
391		if (!off) {
392			brelse(bh);
393			bh = sb_bread(s, block);
394		}
395
396		if (!bh)
397			continue;
398
399		di = (struct bfs_inode *)bh->b_data + off;
400
401		/* test if filesystem is not corrupted */
402
403		i_eoff = le32_to_cpu(di->i_eoffset);
404		i_sblock = le32_to_cpu(di->i_sblock);
405		i_eblock = le32_to_cpu(di->i_eblock);
406		s_size = le32_to_cpu(bfs_sb->s_end);
407
408		if (i_sblock > info->si_blocks ||
409			i_eblock > info->si_blocks ||
410			i_sblock > i_eblock ||
411			(i_eoff != le32_to_cpu(-1) && i_eoff > s_size) ||
412			i_sblock * BFS_BSIZE > i_eoff) {
413
414			printf("Inode 0x%08x corrupted on %s\n", i, s->s_id);
415
416			brelse(bh);
417			ret = -EIO;
418			goto out2;
419		}
420
421		if (!di->i_ino) {
422			info->si_freei++;
423			continue;
424		}
425		set_bit(i, info->si_imap);
426		info->si_freeb -= BFS_FILEBLOCKS(di);
427
428		eblock =  le32_to_cpu(di->i_eblock);
429		if (eblock > info->si_lf_eblk)
430			info->si_lf_eblk = eblock;
431	}
432	brelse(bh);
433	brelse(sbh);
434	bfs_dump_imap("fill_super", s);
435	return 0;
436
437out2:
438	dput(s->s_root);
439	s->s_root = NULL;
 
 
440out1:
441	brelse(sbh);
442out:
443	mutex_destroy(&info->bfs_lock);
444	kfree(info);
445	s->s_fs_info = NULL;
446	return ret;
447}
448
449static struct dentry *bfs_mount(struct file_system_type *fs_type,
450	int flags, const char *dev_name, void *data)
451{
452	return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
453}
454
455static struct file_system_type bfs_fs_type = {
456	.owner		= THIS_MODULE,
457	.name		= "bfs",
458	.mount		= bfs_mount,
459	.kill_sb	= kill_block_super,
460	.fs_flags	= FS_REQUIRES_DEV,
461};
462MODULE_ALIAS_FS("bfs");
463
464static int __init init_bfs_fs(void)
465{
466	int err = init_inodecache();
467	if (err)
468		goto out1;
469	err = register_filesystem(&bfs_fs_type);
470	if (err)
471		goto out;
472	return 0;
473out:
474	destroy_inodecache();
475out1:
476	return err;
477}
478
479static void __exit exit_bfs_fs(void)
480{
481	unregister_filesystem(&bfs_fs_type);
482	destroy_inodecache();
483}
484
485module_init(init_bfs_fs)
486module_exit(exit_bfs_fs)
v4.17
 
  1/*
  2 *	fs/bfs/inode.c
  3 *	BFS superblock and inode operations.
  4 *	Copyright (C) 1999-2006 Tigran Aivazian <aivazian.tigran@gmail.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/buffer_head.h>
 16#include <linux/vfs.h>
 17#include <linux/writeback.h>
 18#include <linux/uio.h>
 19#include <linux/uaccess.h>
 20#include "bfs.h"
 21
 22MODULE_AUTHOR("Tigran Aivazian <aivazian.tigran@gmail.com>");
 23MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
 24MODULE_LICENSE("GPL");
 25
 26#undef DEBUG
 27
 28#ifdef DEBUG
 29#define dprintf(x...)	printf(x)
 30#else
 31#define dprintf(x...)
 32#endif
 33
 34struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
 35{
 36	struct bfs_inode *di;
 37	struct inode *inode;
 38	struct buffer_head *bh;
 39	int block, off;
 40
 41	inode = iget_locked(sb, ino);
 42	if (!inode)
 43		return ERR_PTR(-ENOMEM);
 44	if (!(inode->i_state & I_NEW))
 45		return inode;
 46
 47	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
 48		printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
 49		goto error;
 50	}
 51
 52	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
 53	bh = sb_bread(inode->i_sb, block);
 54	if (!bh) {
 55		printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
 56									ino);
 57		goto error;
 58	}
 59
 60	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
 61	di = (struct bfs_inode *)bh->b_data + off;
 62
 63	inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
 64	if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
 65		inode->i_mode |= S_IFDIR;
 66		inode->i_op = &bfs_dir_inops;
 67		inode->i_fop = &bfs_dir_operations;
 68	} else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
 69		inode->i_mode |= S_IFREG;
 70		inode->i_op = &bfs_file_inops;
 71		inode->i_fop = &bfs_file_operations;
 72		inode->i_mapping->a_ops = &bfs_aops;
 73	}
 74
 75	BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
 76	BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
 77	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
 78	i_uid_write(inode, le32_to_cpu(di->i_uid));
 79	i_gid_write(inode,  le32_to_cpu(di->i_gid));
 80	set_nlink(inode, le32_to_cpu(di->i_nlink));
 81	inode->i_size = BFS_FILESIZE(di);
 82	inode->i_blocks = BFS_FILEBLOCKS(di);
 83	inode->i_atime.tv_sec =  le32_to_cpu(di->i_atime);
 84	inode->i_mtime.tv_sec =  le32_to_cpu(di->i_mtime);
 85	inode->i_ctime.tv_sec =  le32_to_cpu(di->i_ctime);
 86	inode->i_atime.tv_nsec = 0;
 87	inode->i_mtime.tv_nsec = 0;
 88	inode->i_ctime.tv_nsec = 0;
 89
 90	brelse(bh);
 91	unlock_new_inode(inode);
 92	return inode;
 93
 94error:
 95	iget_failed(inode);
 96	return ERR_PTR(-EIO);
 97}
 98
 99static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p)
100{
101	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) {
102		printf("Bad inode number %s:%08x\n", sb->s_id, ino);
103		return ERR_PTR(-EIO);
104	}
105
106	ino -= BFS_ROOT_INO;
107
108	*p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK);
109	if (!*p) {
110		printf("Unable to read inode %s:%08x\n", sb->s_id, ino);
111		return ERR_PTR(-EIO);
112	}
113
114	return (struct bfs_inode *)(*p)->b_data +  ino % BFS_INODES_PER_BLOCK;
115}
116
117static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc)
118{
119	struct bfs_sb_info *info = BFS_SB(inode->i_sb);
120	unsigned int ino = (u16)inode->i_ino;
121        unsigned long i_sblock;
122	struct bfs_inode *di;
123	struct buffer_head *bh;
124	int err = 0;
125
126        dprintf("ino=%08x\n", ino);
127
128	di = find_inode(inode->i_sb, ino, &bh);
129	if (IS_ERR(di))
130		return PTR_ERR(di);
131
132	mutex_lock(&info->bfs_lock);
133
134	if (ino == BFS_ROOT_INO)
135		di->i_vtype = cpu_to_le32(BFS_VDIR);
136	else
137		di->i_vtype = cpu_to_le32(BFS_VREG);
138
139	di->i_ino = cpu_to_le16(ino);
140	di->i_mode = cpu_to_le32(inode->i_mode);
141	di->i_uid = cpu_to_le32(i_uid_read(inode));
142	di->i_gid = cpu_to_le32(i_gid_read(inode));
143	di->i_nlink = cpu_to_le32(inode->i_nlink);
144	di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
145	di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
146	di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
147        i_sblock = BFS_I(inode)->i_sblock;
148	di->i_sblock = cpu_to_le32(i_sblock);
149	di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
150	di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
151
152	mark_buffer_dirty(bh);
153	if (wbc->sync_mode == WB_SYNC_ALL) {
154		sync_dirty_buffer(bh);
155		if (buffer_req(bh) && !buffer_uptodate(bh))
156			err = -EIO;
157	}
158	brelse(bh);
159	mutex_unlock(&info->bfs_lock);
160	return err;
161}
162
163static void bfs_evict_inode(struct inode *inode)
164{
165	unsigned long ino = inode->i_ino;
166	struct bfs_inode *di;
167	struct buffer_head *bh;
168	struct super_block *s = inode->i_sb;
169	struct bfs_sb_info *info = BFS_SB(s);
170	struct bfs_inode_info *bi = BFS_I(inode);
171
172	dprintf("ino=%08lx\n", ino);
173
174	truncate_inode_pages_final(&inode->i_data);
175	invalidate_inode_buffers(inode);
176	clear_inode(inode);
177
178	if (inode->i_nlink)
179		return;
180
181	di = find_inode(s, inode->i_ino, &bh);
182	if (IS_ERR(di))
183		return;
184
185	mutex_lock(&info->bfs_lock);
186	/* clear on-disk inode */
187	memset(di, 0, sizeof(struct bfs_inode));
188	mark_buffer_dirty(bh);
189	brelse(bh);
190
191        if (bi->i_dsk_ino) {
192		if (bi->i_sblock)
193			info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
194		info->si_freei++;
195		clear_bit(ino, info->si_imap);
196		bfs_dump_imap("delete_inode", s);
197        }
198
199	/*
200	 * If this was the last file, make the previous block
201	 * "last block of the last file" even if there is no
202	 * real file there, saves us 1 gap.
203	 */
204	if (info->si_lf_eblk == bi->i_eblock)
205		info->si_lf_eblk = bi->i_sblock - 1;
206	mutex_unlock(&info->bfs_lock);
207}
208
209static void bfs_put_super(struct super_block *s)
210{
211	struct bfs_sb_info *info = BFS_SB(s);
212
213	if (!info)
214		return;
215
216	mutex_destroy(&info->bfs_lock);
217	kfree(info->si_imap);
218	kfree(info);
219	s->s_fs_info = NULL;
220}
221
222static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
223{
224	struct super_block *s = dentry->d_sb;
225	struct bfs_sb_info *info = BFS_SB(s);
226	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
227	buf->f_type = BFS_MAGIC;
228	buf->f_bsize = s->s_blocksize;
229	buf->f_blocks = info->si_blocks;
230	buf->f_bfree = buf->f_bavail = info->si_freeb;
231	buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
232	buf->f_ffree = info->si_freei;
233	buf->f_fsid.val[0] = (u32)id;
234	buf->f_fsid.val[1] = (u32)(id >> 32);
235	buf->f_namelen = BFS_NAMELEN;
236	return 0;
237}
238
239static struct kmem_cache *bfs_inode_cachep;
240
241static struct inode *bfs_alloc_inode(struct super_block *sb)
242{
243	struct bfs_inode_info *bi;
244	bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
245	if (!bi)
246		return NULL;
247	return &bi->vfs_inode;
248}
249
250static void bfs_i_callback(struct rcu_head *head)
251{
252	struct inode *inode = container_of(head, struct inode, i_rcu);
253	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
254}
255
256static void bfs_destroy_inode(struct inode *inode)
257{
258	call_rcu(&inode->i_rcu, bfs_i_callback);
259}
260
261static void init_once(void *foo)
262{
263	struct bfs_inode_info *bi = foo;
264
265	inode_init_once(&bi->vfs_inode);
266}
267
268static int __init init_inodecache(void)
269{
270	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
271					     sizeof(struct bfs_inode_info),
272					     0, (SLAB_RECLAIM_ACCOUNT|
273						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
274					     init_once);
275	if (bfs_inode_cachep == NULL)
276		return -ENOMEM;
277	return 0;
278}
279
280static void destroy_inodecache(void)
281{
282	/*
283	 * Make sure all delayed rcu free inodes are flushed before we
284	 * destroy cache.
285	 */
286	rcu_barrier();
287	kmem_cache_destroy(bfs_inode_cachep);
288}
289
290static const struct super_operations bfs_sops = {
291	.alloc_inode	= bfs_alloc_inode,
292	.destroy_inode	= bfs_destroy_inode,
293	.write_inode	= bfs_write_inode,
294	.evict_inode	= bfs_evict_inode,
295	.put_super	= bfs_put_super,
296	.statfs		= bfs_statfs,
297};
298
299void bfs_dump_imap(const char *prefix, struct super_block *s)
300{
301#ifdef DEBUG
302	int i;
303	char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
304
305	if (!tmpbuf)
306		return;
307	for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
308		if (i > PAGE_SIZE - 100) break;
309		if (test_bit(i, BFS_SB(s)->si_imap))
310			strcat(tmpbuf, "1");
311		else
312			strcat(tmpbuf, "0");
313	}
314	printf("BFS-fs: %s: lasti=%08lx <%s>\n",
315				prefix, BFS_SB(s)->si_lasti, tmpbuf);
316	free_page((unsigned long)tmpbuf);
317#endif
318}
319
320static int bfs_fill_super(struct super_block *s, void *data, int silent)
321{
322	struct buffer_head *bh, *sbh;
323	struct bfs_super_block *bfs_sb;
324	struct inode *inode;
325	unsigned i, imap_len;
326	struct bfs_sb_info *info;
327	int ret = -EINVAL;
328	unsigned long i_sblock, i_eblock, i_eoff, s_size;
329
330	info = kzalloc(sizeof(*info), GFP_KERNEL);
331	if (!info)
332		return -ENOMEM;
333	mutex_init(&info->bfs_lock);
334	s->s_fs_info = info;
 
 
335
336	sb_set_blocksize(s, BFS_BSIZE);
337
338	sbh = sb_bread(s, 0);
339	if (!sbh)
340		goto out;
341	bfs_sb = (struct bfs_super_block *)sbh->b_data;
342	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
343		if (!silent)
344			printf("No BFS filesystem on %s (magic=%08x)\n", 
345				s->s_id,  le32_to_cpu(bfs_sb->s_magic));
346		goto out1;
347	}
348	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
349		printf("%s is unclean, continuing\n", s->s_id);
350
351	s->s_magic = BFS_MAGIC;
352
353	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) {
354		printf("Superblock is corrupted\n");
 
355		goto out1;
356	}
357
358	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
359					sizeof(struct bfs_inode)
360					+ BFS_ROOT_INO - 1;
361	imap_len = (info->si_lasti / 8) + 1;
362	info->si_imap = kzalloc(imap_len, GFP_KERNEL);
363	if (!info->si_imap)
364		goto out1;
 
365	for (i = 0; i < BFS_ROOT_INO; i++)
366		set_bit(i, info->si_imap);
367
368	s->s_op = &bfs_sops;
369	inode = bfs_iget(s, BFS_ROOT_INO);
370	if (IS_ERR(inode)) {
371		ret = PTR_ERR(inode);
372		goto out2;
373	}
374	s->s_root = d_make_root(inode);
375	if (!s->s_root) {
376		ret = -ENOMEM;
377		goto out2;
378	}
379
380	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
381	info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1
382			- le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
383	info->si_freei = 0;
384	info->si_lf_eblk = 0;
385
386	/* can we read the last block? */
387	bh = sb_bread(s, info->si_blocks - 1);
388	if (!bh) {
389		printf("Last block not available: %lu\n", info->si_blocks - 1);
390		ret = -EIO;
391		goto out3;
392	}
393	brelse(bh);
394
395	bh = NULL;
396	for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
397		struct bfs_inode *di;
398		int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
399		int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
400		unsigned long eblock;
401
402		if (!off) {
403			brelse(bh);
404			bh = sb_bread(s, block);
405		}
406
407		if (!bh)
408			continue;
409
410		di = (struct bfs_inode *)bh->b_data + off;
411
412		/* test if filesystem is not corrupted */
413
414		i_eoff = le32_to_cpu(di->i_eoffset);
415		i_sblock = le32_to_cpu(di->i_sblock);
416		i_eblock = le32_to_cpu(di->i_eblock);
417		s_size = le32_to_cpu(bfs_sb->s_end);
418
419		if (i_sblock > info->si_blocks ||
420			i_eblock > info->si_blocks ||
421			i_sblock > i_eblock ||
422			(i_eoff != le32_to_cpu(-1) && i_eoff > s_size) ||
423			i_sblock * BFS_BSIZE > i_eoff) {
424
425			printf("Inode 0x%08x corrupted\n", i);
426
427			brelse(bh);
428			ret = -EIO;
429			goto out3;
430		}
431
432		if (!di->i_ino) {
433			info->si_freei++;
434			continue;
435		}
436		set_bit(i, info->si_imap);
437		info->si_freeb -= BFS_FILEBLOCKS(di);
438
439		eblock =  le32_to_cpu(di->i_eblock);
440		if (eblock > info->si_lf_eblk)
441			info->si_lf_eblk = eblock;
442	}
443	brelse(bh);
444	brelse(sbh);
445	bfs_dump_imap("read_super", s);
446	return 0;
447
448out3:
449	dput(s->s_root);
450	s->s_root = NULL;
451out2:
452	kfree(info->si_imap);
453out1:
454	brelse(sbh);
455out:
456	mutex_destroy(&info->bfs_lock);
457	kfree(info);
458	s->s_fs_info = NULL;
459	return ret;
460}
461
462static struct dentry *bfs_mount(struct file_system_type *fs_type,
463	int flags, const char *dev_name, void *data)
464{
465	return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
466}
467
468static struct file_system_type bfs_fs_type = {
469	.owner		= THIS_MODULE,
470	.name		= "bfs",
471	.mount		= bfs_mount,
472	.kill_sb	= kill_block_super,
473	.fs_flags	= FS_REQUIRES_DEV,
474};
475MODULE_ALIAS_FS("bfs");
476
477static int __init init_bfs_fs(void)
478{
479	int err = init_inodecache();
480	if (err)
481		goto out1;
482        err = register_filesystem(&bfs_fs_type);
483	if (err)
484		goto out;
485	return 0;
486out:
487	destroy_inodecache();
488out1:
489	return err;
490}
491
492static void __exit exit_bfs_fs(void)
493{
494	unregister_filesystem(&bfs_fs_type);
495	destroy_inodecache();
496}
497
498module_init(init_bfs_fs)
499module_exit(exit_bfs_fs)