[linux.git] / fs / bfs / inode.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *	fs/bfs/inode.c
 *	BFS superblock and inode operations.
 *	Copyright (C) 1999-2018 Tigran Aivazian <[email protected]>
 *	From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
 *	Made endianness-clean by Andrew Stribblehill <[email protected]>, 2005.
 */

#include <linux/module.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/buffer_head.h>
#include <linux/vfs.h>
#include <linux/writeback.h>
#include <linux/uio.h>
#include <linux/uaccess.h>
#include "bfs.h"

MODULE_AUTHOR("Tigran Aivazian <[email protected]>");
MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
MODULE_LICENSE("GPL");

#undef DEBUG

#ifdef DEBUG
#define dprintf(x...)	printf(x)
#else
#define dprintf(x...)
#endif

struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
{
	struct bfs_inode *di;
	struct inode *inode;
	struct buffer_head *bh;
	int block, off;

	inode = iget_locked(sb, ino);
	if (!inode)
		return ERR_PTR(-ENOMEM);
	if (!(inode->i_state & I_NEW))
		return inode;

	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
		printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
		goto error;
	}

	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
	bh = sb_bread(inode->i_sb, block);
	if (!bh) {
		printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
									ino);
		goto error;
	}

	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
	di = (struct bfs_inode *)bh->b_data + off;

	inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
	if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
		inode->i_mode |= S_IFDIR;
		inode->i_op = &bfs_dir_inops;
		inode->i_fop = &bfs_dir_operations;
	} else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
		inode->i_mode |= S_IFREG;
		inode->i_op = &bfs_file_inops;
		inode->i_fop = &bfs_file_operations;
		inode->i_mapping->a_ops = &bfs_aops;
	}

	BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
	BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
	i_uid_write(inode, le32_to_cpu(di->i_uid));
	i_gid_write(inode,  le32_to_cpu(di->i_gid));
	set_nlink(inode, le32_to_cpu(di->i_nlink));
	inode->i_size = BFS_FILESIZE(di);
	inode->i_blocks = BFS_FILEBLOCKS(di);
	inode_set_atime(inode, le32_to_cpu(di->i_atime), 0);
	inode_set_mtime(inode, le32_to_cpu(di->i_mtime), 0);
	inode_set_ctime(inode, le32_to_cpu(di->i_ctime), 0);

	brelse(bh);
	unlock_new_inode(inode);
	return inode;

error:
	iget_failed(inode);
	return ERR_PTR(-EIO);
}

static struct bfs_inode *find_inode(struct super_block *sb, u16 ino, struct buffer_head **p)
{
	if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(sb)->si_lasti)) {
		printf("Bad inode number %s:%08x\n", sb->s_id, ino);
		return ERR_PTR(-EIO);
	}

	ino -= BFS_ROOT_INO;

	*p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK);
	if (!*p) {
		printf("Unable to read inode %s:%08x\n", sb->s_id, ino);
		return ERR_PTR(-EIO);
	}

	return (struct bfs_inode *)(*p)->b_data +  ino % BFS_INODES_PER_BLOCK;
}

static int bfs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
	struct bfs_sb_info *info = BFS_SB(inode->i_sb);
	unsigned int ino = (u16)inode->i_ino;
	unsigned long i_sblock;
	struct bfs_inode *di;
	struct buffer_head *bh;
	int err = 0;

	dprintf("ino=%08x\n", ino);

	di = find_inode(inode->i_sb, ino, &bh);
	if (IS_ERR(di))
		return PTR_ERR(di);

	mutex_lock(&info->bfs_lock);

	if (ino == BFS_ROOT_INO)
		di->i_vtype = cpu_to_le32(BFS_VDIR);
	else
		di->i_vtype = cpu_to_le32(BFS_VREG);

	di->i_ino = cpu_to_le16(ino);
	di->i_mode = cpu_to_le32(inode->i_mode);
	di->i_uid = cpu_to_le32(i_uid_read(inode));
	di->i_gid = cpu_to_le32(i_gid_read(inode));
	di->i_nlink = cpu_to_le32(inode->i_nlink);
	di->i_atime = cpu_to_le32(inode_get_atime_sec(inode));
	di->i_mtime = cpu_to_le32(inode_get_mtime_sec(inode));
	di->i_ctime = cpu_to_le32(inode_get_ctime_sec(inode));
	i_sblock = BFS_I(inode)->i_sblock;
	di->i_sblock = cpu_to_le32(i_sblock);
	di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
	di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);

	mark_buffer_dirty(bh);
	if (wbc->sync_mode == WB_SYNC_ALL) {
		sync_dirty_buffer(bh);
		if (buffer_req(bh) && !buffer_uptodate(bh))
			err = -EIO;
	}
	brelse(bh);
	mutex_unlock(&info->bfs_lock);
	return err;
}

static void bfs_evict_inode(struct inode *inode)
{
	unsigned long ino = inode->i_ino;
	struct bfs_inode *di;
	struct buffer_head *bh;
	struct super_block *s = inode->i_sb;
	struct bfs_sb_info *info = BFS_SB(s);
	struct bfs_inode_info *bi = BFS_I(inode);

	dprintf("ino=%08lx\n", ino);

	truncate_inode_pages_final(&inode->i_data);
	invalidate_inode_buffers(inode);
	clear_inode(inode);

	if (inode->i_nlink)
		return;

	di = find_inode(s, inode->i_ino, &bh);
	if (IS_ERR(di))
		return;

	mutex_lock(&info->bfs_lock);
	/* clear on-disk inode */
	memset(di, 0, sizeof(struct bfs_inode));
	mark_buffer_dirty(bh);
	brelse(bh);

	if (bi->i_dsk_ino) {
		if (bi->i_sblock)
			info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
		info->si_freei++;
		clear_bit(ino, info->si_imap);
		bfs_dump_imap("evict_inode", s);
	}

	/*
	 * If this was the last file, make the previous block
	 * "last block of the last file" even if there is no
	 * real file there, saves us 1 gap.
	 */
	if (info->si_lf_eblk == bi->i_eblock)
		info->si_lf_eblk = bi->i_sblock - 1;
	mutex_unlock(&info->bfs_lock);
}

static void bfs_put_super(struct super_block *s)
{
	struct bfs_sb_info *info = BFS_SB(s);

	if (!info)
		return;

	mutex_destroy(&info->bfs_lock);
	kfree(info);
	s->s_fs_info = NULL;
}

static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct super_block *s = dentry->d_sb;
	struct bfs_sb_info *info = BFS_SB(s);
	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
	buf->f_type = BFS_MAGIC;
	buf->f_bsize = s->s_blocksize;
	buf->f_blocks = info->si_blocks;
	buf->f_bfree = buf->f_bavail = info->si_freeb;
	buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
	buf->f_ffree = info->si_freei;
	buf->f_fsid = u64_to_fsid(id);
	buf->f_namelen = BFS_NAMELEN;
	return 0;
}

static struct kmem_cache *bfs_inode_cachep;

static struct inode *bfs_alloc_inode(struct super_block *sb)
{
	struct bfs_inode_info *bi;
	bi = alloc_inode_sb(sb, bfs_inode_cachep, GFP_KERNEL);
	if (!bi)
		return NULL;
	return &bi->vfs_inode;
}

static void bfs_free_inode(struct inode *inode)
{
	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
}

static void init_once(void *foo)
{
	struct bfs_inode_info *bi = foo;

	inode_init_once(&bi->vfs_inode);
}

static int __init init_inodecache(void)
{
	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
					     sizeof(struct bfs_inode_info),
					     0, (SLAB_RECLAIM_ACCOUNT|
						SLAB_ACCOUNT),
					     init_once);
	if (bfs_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	/*
	 * Make sure all delayed rcu free inodes are flushed before we
	 * destroy cache.
	 */
	rcu_barrier();
	kmem_cache_destroy(bfs_inode_cachep);
}

static const struct super_operations bfs_sops = {
	.alloc_inode	= bfs_alloc_inode,
	.free_inode	= bfs_free_inode,
	.write_inode	= bfs_write_inode,
	.evict_inode	= bfs_evict_inode,
	.put_super	= bfs_put_super,
	.statfs		= bfs_statfs,
};

void bfs_dump_imap(const char *prefix, struct super_block *s)
{
#ifdef DEBUG
	int i;
	char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);

	if (!tmpbuf)
		return;
	for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
		if (i > PAGE_SIZE - 100) break;
		if (test_bit(i, BFS_SB(s)->si_imap))
			strcat(tmpbuf, "1");
		else
			strcat(tmpbuf, "0");
	}
	printf("%s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
	free_page((unsigned long)tmpbuf);
#endif
}

static int bfs_fill_super(struct super_block *s, void *data, int silent)
{
	struct buffer_head *bh, *sbh;
	struct bfs_super_block *bfs_sb;
	struct inode *inode;
	unsigned i;
	struct bfs_sb_info *info;
	int ret = -EINVAL;
	unsigned long i_sblock, i_eblock, i_eoff, s_size;

	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;
	mutex_init(&info->bfs_lock);
	s->s_fs_info = info;
	s->s_time_min = 0;
	s->s_time_max = U32_MAX;

	sb_set_blocksize(s, BFS_BSIZE);

	sbh = sb_bread(s, 0);
	if (!sbh)
		goto out;
	bfs_sb = (struct bfs_super_block *)sbh->b_data;
	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
		if (!silent)
			printf("No BFS filesystem on %s (magic=%08x)\n", s->s_id,  le32_to_cpu(bfs_sb->s_magic));
		goto out1;
	}
	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
		printf("%s is unclean, continuing\n", s->s_id);

	s->s_magic = BFS_MAGIC;

	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) ||
	    le32_to_cpu(bfs_sb->s_start) < sizeof(struct bfs_super_block) + sizeof(struct bfs_dirent)) {
		printf("Superblock is corrupted on %s\n", s->s_id);
		goto out1;
	}

	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / sizeof(struct bfs_inode) + BFS_ROOT_INO - 1;
	if (info->si_lasti == BFS_MAX_LASTI)
		printf("NOTE: filesystem %s was created with 512 inodes, the real maximum is 511, mounting anyway\n", s->s_id);
	else if (info->si_lasti > BFS_MAX_LASTI) {
		printf("Impossible last inode number %lu > %d on %s\n", info->si_lasti, BFS_MAX_LASTI, s->s_id);
		goto out1;
	}
	for (i = 0; i < BFS_ROOT_INO; i++)
		set_bit(i, info->si_imap);

	s->s_op = &bfs_sops;
	inode = bfs_iget(s, BFS_ROOT_INO);
	if (IS_ERR(inode)) {
		ret = PTR_ERR(inode);
		goto out1;
	}
	s->s_root = d_make_root(inode);
	if (!s->s_root) {
		ret = -ENOMEM;
		goto out1;
	}

	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
	info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
	info->si_freei = 0;
	info->si_lf_eblk = 0;

	/* can we read the last block? */
	bh = sb_bread(s, info->si_blocks - 1);
	if (!bh) {
		printf("Last block not available on %s: %lu\n", s->s_id, info->si_blocks - 1);
		ret = -EIO;
		goto out2;
	}
	brelse(bh);

	bh = NULL;
	for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
		struct bfs_inode *di;
		int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
		int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
		unsigned long eblock;

		if (!off) {
			brelse(bh);
			bh = sb_bread(s, block);
		}

		if (!bh)
			continue;

		di = (struct bfs_inode *)bh->b_data + off;

		/* test if filesystem is not corrupted */

		i_eoff = le32_to_cpu(di->i_eoffset);
		i_sblock = le32_to_cpu(di->i_sblock);
		i_eblock = le32_to_cpu(di->i_eblock);
		s_size = le32_to_cpu(bfs_sb->s_end);

		if (i_sblock > info->si_blocks ||
			i_eblock > info->si_blocks ||
			i_sblock > i_eblock ||
			(i_eoff != le32_to_cpu(-1) && i_eoff > s_size) ||
			i_sblock * BFS_BSIZE > i_eoff) {

			printf("Inode 0x%08x corrupted on %s\n", i, s->s_id);

			brelse(bh);
			ret = -EIO;
			goto out2;
		}

		if (!di->i_ino) {
			info->si_freei++;
			continue;
		}
		set_bit(i, info->si_imap);
		info->si_freeb -= BFS_FILEBLOCKS(di);

		eblock =  le32_to_cpu(di->i_eblock);
		if (eblock > info->si_lf_eblk)
			info->si_lf_eblk = eblock;
	}
	brelse(bh);
	brelse(sbh);
	bfs_dump_imap("fill_super", s);
	return 0;

out2:
	dput(s->s_root);
	s->s_root = NULL;
out1:
	brelse(sbh);
out:
	mutex_destroy(&info->bfs_lock);
	kfree(info);
	s->s_fs_info = NULL;
	return ret;
}

static struct dentry *bfs_mount(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data)
{
	return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
}

static struct file_system_type bfs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "bfs",
	.mount		= bfs_mount,
	.kill_sb	= kill_block_super,
	.fs_flags	= FS_REQUIRES_DEV,
};
MODULE_ALIAS_FS("bfs");

static int __init init_bfs_fs(void)
{
	int err = init_inodecache();
	if (err)
		goto out1;
	err = register_filesystem(&bfs_fs_type);
	if (err)
		goto out;
	return 0;
out:
	destroy_inodecache();
out1:
	return err;
}

static void __exit exit_bfs_fs(void)
{
	unregister_filesystem(&bfs_fs_type);
	destroy_inodecache();
}

module_init(init_bfs_fs)
module_exit(exit_bfs_fs)
Commit	Line	Data
09c434b8	1	// SPDX-License-Identifier: GPL-2.0-only
1da177e4 LT	2	/*
	3	* fs/bfs/inode.c
	4	* BFS superblock and inode operations.
d1877155	5	* Copyright (C) 1999-2018 Tigran Aivazian <[email protected]>
1da177e4	6	* From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
d1877155	7	* Made endianness-clean by Andrew Stribblehill <[email protected]>, 2005.
1da177e4 LT	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>
1da177e4 LT	15	#include <linux/buffer_head.h>
1da177e4 LT	16	#include <linux/vfs.h>
a9185b41	17	#include <linux/writeback.h>
e2e40f2c	18	#include <linux/uio.h>
7c0f6ba6	19	#include <linux/uaccess.h>
1da177e4 LT	20	#include "bfs.h"
1da177e4 LT	21
cea58224	22	MODULE_AUTHOR("Tigran Aivazian <[email protected]>");
1da177e4 LT	23	MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
	24	MODULE_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
e33ab086	34	struct inode bfs_iget(struct super_block sb, unsigned long ino)
1da177e4	35	{
f433dc56	36	struct bfs_inode *di;
e33ab086	37	struct inode *inode;
f433dc56	38	struct buffer_head *bh;
1da177e4 LT	39	int block, off;
1da177e4 LT	40
e33ab086	41	inode = iget_locked(sb, ino);
821ff77c	42	if (!inode)
e33ab086 DH	43	return ERR_PTR(-ENOMEM);
	44	if (!(inode->i_state & I_NEW))
	45	return inode;
	46
f433dc56	47	if ((ino < BFS_ROOT_INO) \|\| (ino > BFS_SB(inode->i_sb)->si_lasti)) {
1da177e4	48	printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
e33ab086	49	goto error;
1da177e4 LT	50	}
1da177e4 LT	51
f433dc56	52	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
1da177e4 LT	53	bh = sb_bread(inode->i_sb, block);
1da177e4 LT	54	if (!bh) {
f433dc56 DV	55	printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
f433dc56 DV	56	ino);
e33ab086	57	goto error;
1da177e4 LT	58	}
	59
	60	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
	61	di = (struct bfs_inode *)bh->b_data + off;
	62
f433dc56	63	inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
fac92bec	64	if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
1da177e4 LT	65	inode->i_mode \|= S_IFDIR;
	66	inode->i_op = &bfs_dir_inops;
	67	inode->i_fop = &bfs_dir_operations;
fac92bec	68	} else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
1da177e4 LT	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
fac92bec AS	75	BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock);
fac92bec AS	76	BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock);
f433dc56	77	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
7f5b82b8 EB	78	i_uid_write(inode, le32_to_cpu(di->i_uid));
7f5b82b8 EB	79	i_gid_write(inode, le32_to_cpu(di->i_gid));
bfe86848	80	set_nlink(inode, le32_to_cpu(di->i_nlink));
1da177e4 LT	81	inode->i_size = BFS_FILESIZE(di);
1da177e4 LT	82	inode->i_blocks = BFS_FILEBLOCKS(di);
ce17a80c JL	83	inode_set_atime(inode, le32_to_cpu(di->i_atime), 0);
ce17a80c JL	84	inode_set_mtime(inode, le32_to_cpu(di->i_mtime), 0);
73d9b9d0	85	inode_set_ctime(inode, le32_to_cpu(di->i_ctime), 0);
1da177e4 LT	86
1da177e4 LT	87	brelse(bh);
e33ab086 DH	88	unlock_new_inode(inode);
	89	return inode;
	90
	91	error:
	92	iget_failed(inode);
	93	return ERR_PTR(-EIO);
1da177e4 LT	94	}
1da177e4 LT	95
9df2f851 AV	96	static 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
a9185b41	114	static int bfs_write_inode(struct inode inode, struct writeback_control wbc)
1da177e4	115	{
4427f0c3	116	struct bfs_sb_info *info = BFS_SB(inode->i_sb);
fac92bec	117	unsigned int ino = (u16)inode->i_ino;
d1877155	118	unsigned long i_sblock;
f433dc56 DV	119	struct bfs_inode *di;
f433dc56 DV	120	struct buffer_head *bh;
4427f0c3	121	int err = 0;
1da177e4	122
d1877155	123	dprintf("ino=%08x\n", ino);
fac92bec	124
9df2f851 AV	125	di = find_inode(inode->i_sb, ino, &bh);
	126	if (IS_ERR(di))
	127	return PTR_ERR(di);
1da177e4	128
3f165e4c	129	mutex_lock(&info->bfs_lock);
1da177e4	130
fac92bec AS	131	if (ino == BFS_ROOT_INO)
fac92bec AS	132	di->i_vtype = cpu_to_le32(BFS_VDIR);
1da177e4	133	else
fac92bec AS	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);
7f5b82b8 EB	138	di->i_uid = cpu_to_le32(i_uid_read(inode));
7f5b82b8 EB	139	di->i_gid = cpu_to_le32(i_gid_read(inode));
fac92bec	140	di->i_nlink = cpu_to_le32(inode->i_nlink);
ce17a80c JL	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));
d1877155	144	i_sblock = BFS_I(inode)->i_sblock;
fac92bec AS	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);
1da177e4 LT	148
1da177e4 LT	149	mark_buffer_dirty(bh);
a9185b41	150	if (wbc->sync_mode == WB_SYNC_ALL) {
4427f0c3 AV	151	sync_dirty_buffer(bh);
	152	if (buffer_req(bh) && !buffer_uptodate(bh))
	153	err = -EIO;
	154	}
1da177e4	155	brelse(bh);
3f165e4c	156	mutex_unlock(&info->bfs_lock);
4427f0c3	157	return err;
1da177e4 LT	158	}
1da177e4 LT	159
9df2f851	160	static void bfs_evict_inode(struct inode *inode)
1da177e4 LT	161	{
1da177e4 LT	162	unsigned long ino = inode->i_ino;
f433dc56 DV	163	struct bfs_inode *di;
f433dc56 DV	164	struct buffer_head *bh;
f433dc56 DV	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);
1da177e4	168
fac92bec	169	dprintf("ino=%08lx\n", ino);
1da177e4	170
91b0abe3	171	truncate_inode_pages_final(&inode->i_data);
9df2f851	172	invalidate_inode_buffers(inode);
dbd5768f	173	clear_inode(inode);
fef26658	174
9df2f851	175	if (inode->i_nlink)
1da177e4	176	return;
f433dc56	177
9df2f851 AV	178	di = find_inode(s, inode->i_ino, &bh);
9df2f851 AV	179	if (IS_ERR(di))
1da177e4	180	return;
9df2f851 AV	181
	182	mutex_lock(&info->bfs_lock);
	183	/* clear on-disk inode */
	184	memset(di, 0, sizeof(struct bfs_inode));
f433dc56 DV	185	mark_buffer_dirty(bh);
	186	brelse(bh);
	187
d1877155	188	if (bi->i_dsk_ino) {
7e46aa5c AV	189	if (bi->i_sblock)
7e46aa5c AV	190	info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
1da177e4	191	info->si_freei++;
fac92bec	192	clear_bit(ino, info->si_imap);
d1877155 TA	193	bfs_dump_imap("evict_inode", s);
d1877155 TA	194	}
1da177e4	195
f433dc56 DV	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	*/
4e29d50a	201	if (info->si_lf_eblk == bi->i_eblock)
f433dc56	202	info->si_lf_eblk = bi->i_sblock - 1;
3f165e4c	203	mutex_unlock(&info->bfs_lock);
1da177e4 LT	204	}
	205
	206	static void bfs_put_super(struct super_block *s)
	207	{
	208	struct bfs_sb_info *info = BFS_SB(s);
3f165e4c	209
e1f89ec9 ES	210	if (!info)
	211	return;
	212
3f165e4c	213	mutex_destroy(&info->bfs_lock);
1da177e4 LT	214	kfree(info);
	215	s->s_fs_info = NULL;
	216	}
	217
726c3342	218	static int bfs_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4	219	{
726c3342	220	struct super_block *s = dentry->d_sb;
1da177e4 LT	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;
6d1349c7	229	buf->f_fsid = u64_to_fsid(id);
1da177e4 LT	230	buf->f_namelen = BFS_NAMELEN;
	231	return 0;
	232	}
	233
f433dc56	234	static struct kmem_cache *bfs_inode_cachep;
1da177e4 LT	235
	236	static struct inode bfs_alloc_inode(struct super_block sb)
	237	{
	238	struct bfs_inode_info *bi;
fd60b288	239	bi = alloc_inode_sb(sb, bfs_inode_cachep, GFP_KERNEL);
1da177e4 LT	240	if (!bi)
	241	return NULL;
	242	return &bi->vfs_inode;
	243	}
	244
8d8fc9cb	245	static void bfs_free_inode(struct inode *inode)
1da177e4 LT	246	{
	247	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
	248	}
	249
51cc5068	250	static void init_once(void *foo)
1da177e4 LT	251	{
	252	struct bfs_inode_info *bi = foo;
	253
a35afb83	254	inode_init_once(&bi->vfs_inode);
1da177e4	255	}
20c2df83	256
758b4440	257	static int __init init_inodecache(void)
1da177e4 LT	258	{
	259	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
	260	sizeof(struct bfs_inode_info),
fffb60f9	261	0, (SLAB_RECLAIM_ACCOUNT\|
f88c3fb8	262	SLAB_ACCOUNT),
20c2df83	263	init_once);
1da177e4 LT	264	if (bfs_inode_cachep == NULL)
	265	return -ENOMEM;
	266	return 0;
	267	}
	268
	269	static void destroy_inodecache(void)
	270	{
8c0a8537 KS	271	/*
	272	* Make sure all delayed rcu free inodes are flushed before we
	273	* destroy cache.
	274	*/
	275	rcu_barrier();
1a1d92c1	276	kmem_cache_destroy(bfs_inode_cachep);
1da177e4 LT	277	}
1da177e4 LT	278
ee9b6d61	279	static const struct super_operations bfs_sops = {
1da177e4	280	.alloc_inode = bfs_alloc_inode,
8d8fc9cb	281	.free_inode = bfs_free_inode,
1da177e4	282	.write_inode = bfs_write_inode,
9df2f851	283	.evict_inode = bfs_evict_inode,
1da177e4	284	.put_super = bfs_put_super,
1da177e4 LT	285	.statfs = bfs_statfs,
	286	};
	287
1da85fdf	288	void bfs_dump_imap(const char prefix, struct super_block s)
1da177e4	289	{
fac92bec	290	#ifdef DEBUG
1da177e4 LT	291	int i;
	292	char tmpbuf = (char )get_zeroed_page(GFP_KERNEL);
	293
	294	if (!tmpbuf)
	295	return;
f433dc56 DV	296	for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
f433dc56 DV	297	if (i > PAGE_SIZE - 100) break;
1da177e4 LT	298	if (test_bit(i, BFS_SB(s)->si_imap))
	299	strcat(tmpbuf, "1");
	300	else
	301	strcat(tmpbuf, "0");
	302	}
d1877155	303	printf("%s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
1da177e4 LT	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	{
4e29d50a	310	struct buffer_head bh, sbh;
f433dc56 DV	311	struct bfs_super_block *bfs_sb;
f433dc56 DV	312	struct inode *inode;
d1877155	313	unsigned i;
f433dc56	314	struct bfs_sb_info *info;
5998649f	315	int ret = -EINVAL;
e1f89ec9	316	unsigned long i_sblock, i_eblock, i_eoff, s_size;
1da177e4	317
f8314dc6	318	info = kzalloc(sizeof(*info), GFP_KERNEL);
ba13d597	319	if (!info)
1da177e4	320	return -ENOMEM;
5998649f	321	mutex_init(&info->bfs_lock);
1da177e4	322	s->s_fs_info = info;
22b13969 DD	323	s->s_time_min = 0;
22b13969 DD	324	s->s_time_max = U32_MAX;
1da177e4 LT	325
	326	sb_set_blocksize(s, BFS_BSIZE);
	327
4e29d50a AB	328	sbh = sb_bread(s, 0);
4e29d50a AB	329	if (!sbh)
1da177e4	330	goto out;
4e29d50a	331	bfs_sb = (struct bfs_super_block *)sbh->b_data;
fac92bec	332	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
1da177e4	333	if (!silent)
d1877155	334	printf("No BFS filesystem on %s (magic=%08x)\n", s->s_id, le32_to_cpu(bfs_sb->s_magic));
5998649f	335	goto out1;
1da177e4 LT	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;
e1f89ec9	341
9f2df09a	342	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end) \|\|
d1877155 TA	343	le32_to_cpu(bfs_sb->s_start) < sizeof(struct bfs_super_block) + sizeof(struct bfs_dirent)) {
d1877155 TA	344	printf("Superblock is corrupted on %s\n", s->s_id);
5998649f	345	goto out1;
e1f89ec9 ES	346	}
e1f89ec9 ES	347
d1877155 TA	348	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) / sizeof(struct bfs_inode) + BFS_ROOT_INO - 1;
d1877155 TA	349	if (info->si_lasti == BFS_MAX_LASTI)
dc889b8d	350	printf("NOTE: filesystem %s was created with 512 inodes, the real maximum is 511, mounting anyway\n", s->s_id);
d1877155 TA	351	else if (info->si_lasti > BFS_MAX_LASTI) {
d1877155 TA	352	printf("Impossible last inode number %lu > %d on %s\n", info->si_lasti, BFS_MAX_LASTI, s->s_id);
5998649f	353	goto out1;
9f2df09a	354	}
f433dc56	355	for (i = 0; i < BFS_ROOT_INO; i++)
1da177e4 LT	356	set_bit(i, info->si_imap);
	357
	358	s->s_op = &bfs_sops;
e33ab086 DH	359	inode = bfs_iget(s, BFS_ROOT_INO);
	360	if (IS_ERR(inode)) {
	361	ret = PTR_ERR(inode);
d1877155	362	goto out1;
1da177e4	363	}
48fde701	364	s->s_root = d_make_root(inode);
1da177e4	365	if (!s->s_root) {
e33ab086	366	ret = -ENOMEM;
d1877155	367	goto out1;
1da177e4 LT	368	}
1da177e4 LT	369
f433dc56	370	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
d1877155	371	info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
1da177e4 LT	372	info->si_freei = 0;
1da177e4 LT	373	info->si_lf_eblk = 0;
50682bb4 ES	374
	375	/* can we read the last block? */
	376	bh = sb_bread(s, info->si_blocks - 1);
	377	if (!bh) {
d1877155	378	printf("Last block not available on %s: %lu\n", s->s_id, info->si_blocks - 1);
50682bb4	379	ret = -EIO;
d1877155	380	goto out2;
50682bb4 ES	381	}
	382	brelse(bh);
	383
c2b513df	384	bh = NULL;
f433dc56	385	for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
c2b513df	386	struct bfs_inode *di;
f433dc56	387	int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
c2b513df	388	int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
75b25b4c	389	unsigned long eblock;
c2b513df AV	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
e1f89ec9 ES	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 \|\|
5f9f48f5	411	(i_eoff != le32_to_cpu(-1) && i_eoff > s_size) \|\|
e1f89ec9 ES	412	i_sblock * BFS_BSIZE > i_eoff) {
e1f89ec9 ES	413
d1877155	414	printf("Inode 0x%08x corrupted on %s\n", i, s->s_id);
e1f89ec9 ES	415
e1f89ec9 ES	416	brelse(bh);
5998649f	417	ret = -EIO;
d1877155	418	goto out2;
e1f89ec9 ES	419	}
e1f89ec9 ES	420
c2b513df	421	if (!di->i_ino) {
1da177e4	422	info->si_freei++;
c2b513df AV	423	continue;
	424	}
	425	set_bit(i, info->si_imap);
	426	info->si_freeb -= BFS_FILEBLOCKS(di);
	427
c2b513df	428	eblock = le32_to_cpu(di->i_eblock);
f433dc56	429	if (eblock > info->si_lf_eblk)
c2b513df	430	info->si_lf_eblk = eblock;
1da177e4	431	}
c2b513df	432	brelse(bh);
4e29d50a	433	brelse(sbh);
d1877155	434	bfs_dump_imap("fill_super", s);
1da177e4 LT	435	return 0;
1da177e4 LT	436
d1877155	437	out2:
5998649f AV	438	dput(s->s_root);
5998649f AV	439	s->s_root = NULL;
5998649f	440	out1:
4e29d50a	441	brelse(sbh);
1da177e4	442	out:
5998649f	443	mutex_destroy(&info->bfs_lock);
1da177e4 LT	444	kfree(info);
1da177e4 LT	445	s->s_fs_info = NULL;
e33ab086	446	return ret;
1da177e4 LT	447	}
1da177e4 LT	448
152a0836 AV	449	static struct dentry bfs_mount(struct file_system_type fs_type,
152a0836 AV	450	int flags, const char dev_name, void data)
1da177e4	451	{
152a0836	452	return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
1da177e4 LT	453	}
	454
	455	static struct file_system_type bfs_fs_type = {
	456	.owner = THIS_MODULE,
	457	.name = "bfs",
152a0836	458	.mount = bfs_mount,
1da177e4 LT	459	.kill_sb = kill_block_super,
	460	.fs_flags = FS_REQUIRES_DEV,
	461	};
7f78e035	462	MODULE_ALIAS_FS("bfs");
1da177e4 LT	463
	464	static int __init init_bfs_fs(void)
	465	{
	466	int err = init_inodecache();
	467	if (err)
	468	goto out1;
d1877155	469	err = register_filesystem(&bfs_fs_type);
1da177e4 LT	470	if (err)
	471	goto out;
	472	return 0;
	473	out:
	474	destroy_inodecache();
	475	out1:
	476	return err;
	477	}
	478
	479	static void __exit exit_bfs_fs(void)
	480	{
	481	unregister_filesystem(&bfs_fs_type);
	482	destroy_inodecache();
	483	}
	484
	485	module_init(init_bfs_fs)
	486	module_exit(exit_bfs_fs)