[net-next-2.6.git] / fs / bfs / inode.c

/*
 *	fs/bfs/inode.c
 *	BFS superblock and inode operations.
 *	Copyright (C) 1999-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
 *	From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
 *
 *      Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 2005.
 */

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

MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
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

static void bfs_write_super(struct super_block *s);
void dump_imap(const char *prefix, struct super_block *s);

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 (IS_ERR(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);
	inode->i_uid =  le32_to_cpu(di->i_uid);
	inode->i_gid =  le32_to_cpu(di->i_gid);
	inode->i_nlink =  le32_to_cpu(di->i_nlink);
	inode->i_size = BFS_FILESIZE(di);
	inode->i_blocks = BFS_FILEBLOCKS(di);
	inode->i_atime.tv_sec =  le32_to_cpu(di->i_atime);
	inode->i_mtime.tv_sec =  le32_to_cpu(di->i_mtime);
	inode->i_ctime.tv_sec =  le32_to_cpu(di->i_ctime);
	inode->i_atime.tv_nsec = 0;
	inode->i_mtime.tv_nsec = 0;
	inode->i_ctime.tv_nsec = 0;

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

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

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 block, off;
	int err = 0;

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

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

	mutex_lock(&info->bfs_lock);
	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:%08x\n",
				inode->i_sb->s_id, ino);
		mutex_unlock(&info->bfs_lock);
		return -EIO;
	}

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

	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(inode->i_uid);
	di->i_gid = cpu_to_le32(inode->i_gid);
	di->i_nlink = cpu_to_le32(inode->i_nlink);
	di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
	di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
	di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
        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_delete_inode(struct inode *inode)
{
	unsigned long ino = inode->i_ino;
	struct bfs_inode *di;
	struct buffer_head *bh;
	int block, off;
	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(&inode->i_data, 0);

	if ((ino < BFS_ROOT_INO) || (ino > info->si_lasti)) {
		printf("invalid ino=%08lx\n", ino);
		return;
	}
	
	inode->i_size = 0;
	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
	mutex_lock(&info->bfs_lock);
	mark_inode_dirty(inode);

	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
	bh = sb_bread(s, block);
	if (!bh) {
		printf("Unable to read inode %s:%08lx\n",
					inode->i_sb->s_id, ino);
		mutex_unlock(&info->bfs_lock);
		return;
	}
	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
	di = (struct bfs_inode *)bh->b_data + off;
	memset((void *)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);
		dump_imap("delete_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;
		mark_buffer_dirty(info->si_sbh);
	}
	mutex_unlock(&info->bfs_lock);
	clear_inode(inode);
}

static int bfs_sync_fs(struct super_block *sb, int wait)
{
	struct bfs_sb_info *info = BFS_SB(sb);

	mutex_lock(&info->bfs_lock);
	mark_buffer_dirty(info->si_sbh);
	sb->s_dirt = 0;
	mutex_unlock(&info->bfs_lock);

	return 0;
}

static void bfs_write_super(struct super_block *sb)
{
	if (!(sb->s_flags & MS_RDONLY))
		bfs_sync_fs(sb, 1);
	else
		sb->s_dirt = 0;
}

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

	if (!info)
		return;

	lock_kernel();

	if (s->s_dirt)
		bfs_write_super(s);

	brelse(info->si_sbh);
	mutex_destroy(&info->bfs_lock);
	kfree(info->si_imap);
	kfree(info);
	s->s_fs_info = NULL;

	unlock_kernel();
}

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.val[0] = (u32)id;
	buf->f_fsid.val[1] = (u32)(id >> 32);
	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 = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
	if (!bi)
		return NULL;
	return &bi->vfs_inode;
}

static void bfs_destroy_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_inodecache(void)
{
	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
					     sizeof(struct bfs_inode_info),
					     0, (SLAB_RECLAIM_ACCOUNT|
						SLAB_MEM_SPREAD),
					     init_once);
	if (bfs_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	kmem_cache_destroy(bfs_inode_cachep);
}

static const struct super_operations bfs_sops = {
	.alloc_inode	= bfs_alloc_inode,
	.destroy_inode	= bfs_destroy_inode,
	.write_inode	= bfs_write_inode,
	.delete_inode	= bfs_delete_inode,
	.put_super	= bfs_put_super,
	.write_super	= bfs_write_super,
	.sync_fs	= bfs_sync_fs,
	.statfs		= bfs_statfs,
};

void 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("BFS-fs: %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;
	struct bfs_super_block *bfs_sb;
	struct inode *inode;
	unsigned i, imap_len;
	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;

	sb_set_blocksize(s, BFS_BSIZE);

	info->si_sbh = sb_bread(s, 0);
	if (!info->si_sbh)
		goto out;
	bfs_sb = (struct bfs_super_block *)info->si_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)) {
		printf("Superblock is corrupted\n");
		goto out1;
	}

	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
					sizeof(struct bfs_inode)
					+ BFS_ROOT_INO - 1;
	imap_len = (info->si_lasti / 8) + 1;
	info->si_imap = kzalloc(imap_len, GFP_KERNEL);
	if (!info->si_imap)
		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 out2;
	}
	s->s_root = d_alloc_root(inode);
	if (!s->s_root) {
		iput(inode);
		ret = -ENOMEM;
		goto out2;
	}

	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: %lu\n", info->si_blocks - 1);
		ret = -EIO;
		goto out3;
	}
	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 > s_size ||
			i_sblock * BFS_BSIZE > i_eoff) {

			printf("Inode 0x%08x corrupted\n", i);

			brelse(bh);
			ret = -EIO;
			goto out3;
		}

		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);
	if (!(s->s_flags & MS_RDONLY)) {
		mark_buffer_dirty(info->si_sbh);
		s->s_dirt = 1;
	} 
	dump_imap("read_super", s);
	return 0;

out3:
	dput(s->s_root);
	s->s_root = NULL;
out2:
	kfree(info->si_imap);
out1:
	brelse(info->si_sbh);
out:
	mutex_destroy(&info->bfs_lock);
	kfree(info);
	s->s_fs_info = NULL;
	return ret;
}

static int bfs_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
	return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt);
}

static struct file_system_type bfs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "bfs",
	.get_sb		= bfs_get_sb,
	.kill_sb	= kill_block_super,
	.fs_flags	= FS_REQUIRES_DEV,
};

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
1da177e4 LT	1	/*
	2	* fs/bfs/inode.c
	3	* BFS superblock and inode operations.
69688262	4	* Copyright (C) 1999-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
1da177e4	5	* From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
fac92bec AS	6	*
fac92bec AS	7	* Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 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>
	15	#include <linux/smp_lock.h>
	16	#include <linux/buffer_head.h>
	17	#include <linux/vfs.h>
a9185b41	18	#include <linux/writeback.h>
1da177e4 LT	19	#include <asm/uaccess.h>
	20	#include "bfs.h"
	21
69688262	22	MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
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
8c85e125	34	static void bfs_write_super(struct super_block *s);
f433dc56	35	void dump_imap(const char prefix, struct super_block s);
1da177e4	36
e33ab086	37	struct inode bfs_iget(struct super_block sb, unsigned long ino)
1da177e4	38	{
f433dc56	39	struct bfs_inode *di;
e33ab086	40	struct inode *inode;
f433dc56	41	struct buffer_head *bh;
1da177e4 LT	42	int block, off;
1da177e4 LT	43
e33ab086 DH	44	inode = iget_locked(sb, ino);
	45	if (IS_ERR(inode))
	46	return ERR_PTR(-ENOMEM);
	47	if (!(inode->i_state & I_NEW))
	48	return inode;
	49
f433dc56	50	if ((ino < BFS_ROOT_INO) \|\| (ino > BFS_SB(inode->i_sb)->si_lasti)) {
1da177e4	51	printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
e33ab086	52	goto error;
1da177e4 LT	53	}
1da177e4 LT	54
f433dc56	55	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
1da177e4 LT	56	bh = sb_bread(inode->i_sb, block);
1da177e4 LT	57	if (!bh) {
f433dc56 DV	58	printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
f433dc56 DV	59	ino);
e33ab086	60	goto error;
1da177e4 LT	61	}
	62
	63	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
	64	di = (struct bfs_inode *)bh->b_data + off;
	65
f433dc56	66	inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
fac92bec	67	if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
1da177e4 LT	68	inode->i_mode \|= S_IFDIR;
	69	inode->i_op = &bfs_dir_inops;
	70	inode->i_fop = &bfs_dir_operations;
fac92bec	71	} else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
1da177e4 LT	72	inode->i_mode \|= S_IFREG;
	73	inode->i_op = &bfs_file_inops;
	74	inode->i_fop = &bfs_file_operations;
	75	inode->i_mapping->a_ops = &bfs_aops;
	76	}
	77
fac92bec AS	78	BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock);
fac92bec AS	79	BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock);
f433dc56	80	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
fac92bec AS	81	inode->i_uid = le32_to_cpu(di->i_uid);
	82	inode->i_gid = le32_to_cpu(di->i_gid);
	83	inode->i_nlink = le32_to_cpu(di->i_nlink);
1da177e4 LT	84	inode->i_size = BFS_FILESIZE(di);
1da177e4 LT	85	inode->i_blocks = BFS_FILEBLOCKS(di);
fac92bec AS	86	inode->i_atime.tv_sec = le32_to_cpu(di->i_atime);
	87	inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime);
	88	inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime);
1da177e4 LT	89	inode->i_atime.tv_nsec = 0;
	90	inode->i_mtime.tv_nsec = 0;
	91	inode->i_ctime.tv_nsec = 0;
1da177e4 LT	92
1da177e4 LT	93	brelse(bh);
e33ab086 DH	94	unlock_new_inode(inode);
	95	return inode;
	96
	97	error:
	98	iget_failed(inode);
	99	return ERR_PTR(-EIO);
1da177e4 LT	100	}
1da177e4 LT	101
a9185b41	102	static int bfs_write_inode(struct inode inode, struct writeback_control wbc)
1da177e4	103	{
4427f0c3	104	struct bfs_sb_info *info = BFS_SB(inode->i_sb);
fac92bec AS	105	unsigned int ino = (u16)inode->i_ino;
fac92bec AS	106	unsigned long i_sblock;
f433dc56 DV	107	struct bfs_inode *di;
f433dc56 DV	108	struct buffer_head *bh;
1da177e4	109	int block, off;
4427f0c3	110	int err = 0;
1da177e4	111
fac92bec AS	112	dprintf("ino=%08x\n", ino);
fac92bec AS	113
f433dc56	114	if ((ino < BFS_ROOT_INO) \|\| (ino > BFS_SB(inode->i_sb)->si_lasti)) {
fac92bec	115	printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
1da177e4 LT	116	return -EIO;
	117	}
	118
3f165e4c	119	mutex_lock(&info->bfs_lock);
f433dc56	120	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
1da177e4 LT	121	bh = sb_bread(inode->i_sb, block);
1da177e4 LT	122	if (!bh) {
f433dc56 DV	123	printf("Unable to read inode %s:%08x\n",
f433dc56 DV	124	inode->i_sb->s_id, ino);
3f165e4c	125	mutex_unlock(&info->bfs_lock);
1da177e4 LT	126	return -EIO;
	127	}
	128
f433dc56	129	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
1da177e4 LT	130	di = (struct bfs_inode *)bh->b_data + off;
1da177e4 LT	131
fac92bec AS	132	if (ino == BFS_ROOT_INO)
fac92bec AS	133	di->i_vtype = cpu_to_le32(BFS_VDIR);
1da177e4	134	else
fac92bec AS	135	di->i_vtype = cpu_to_le32(BFS_VREG);
	136
	137	di->i_ino = cpu_to_le16(ino);
	138	di->i_mode = cpu_to_le32(inode->i_mode);
	139	di->i_uid = cpu_to_le32(inode->i_uid);
	140	di->i_gid = cpu_to_le32(inode->i_gid);
	141	di->i_nlink = cpu_to_le32(inode->i_nlink);
	142	di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
	143	di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
	144	di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
	145	i_sblock = BFS_I(inode)->i_sblock;
	146	di->i_sblock = cpu_to_le32(i_sblock);
	147	di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
	148	di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
1da177e4 LT	149
1da177e4 LT	150	mark_buffer_dirty(bh);
a9185b41	151	if (wbc->sync_mode == WB_SYNC_ALL) {
4427f0c3 AV	152	sync_dirty_buffer(bh);
	153	if (buffer_req(bh) && !buffer_uptodate(bh))
	154	err = -EIO;
	155	}
1da177e4	156	brelse(bh);
3f165e4c	157	mutex_unlock(&info->bfs_lock);
4427f0c3	158	return err;
1da177e4 LT	159	}
1da177e4 LT	160
f433dc56	161	static void bfs_delete_inode(struct inode *inode)
1da177e4 LT	162	{
1da177e4 LT	163	unsigned long ino = inode->i_ino;
f433dc56 DV	164	struct bfs_inode *di;
f433dc56 DV	165	struct buffer_head *bh;
1da177e4	166	int block, off;
f433dc56 DV	167	struct super_block *s = inode->i_sb;
	168	struct bfs_sb_info *info = BFS_SB(s);
	169	struct bfs_inode_info *bi = BFS_I(inode);
1da177e4	170
fac92bec	171	dprintf("ino=%08lx\n", ino);
1da177e4	172
fef26658 MF	173	truncate_inode_pages(&inode->i_data, 0);
fef26658 MF	174
f433dc56	175	if ((ino < BFS_ROOT_INO) \|\| (ino > info->si_lasti)) {
fac92bec	176	printf("invalid ino=%08lx\n", ino);
1da177e4 LT	177	return;
	178	}
	179
	180	inode->i_size = 0;
	181	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
3f165e4c	182	mutex_lock(&info->bfs_lock);
1da177e4	183	mark_inode_dirty(inode);
f433dc56 DV	184
f433dc56 DV	185	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
1da177e4 LT	186	bh = sb_bread(s, block);
1da177e4 LT	187	if (!bh) {
f433dc56 DV	188	printf("Unable to read inode %s:%08lx\n",
f433dc56 DV	189	inode->i_sb->s_id, ino);
3f165e4c	190	mutex_unlock(&info->bfs_lock);
1da177e4 LT	191	return;
1da177e4 LT	192	}
f433dc56 DV	193	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
	194	di = (struct bfs_inode *)bh->b_data + off;
	195	memset((void *)di, 0, sizeof(struct bfs_inode));
	196	mark_buffer_dirty(bh);
	197	brelse(bh);
	198
fac92bec	199	if (bi->i_dsk_ino) {
7e46aa5c AV	200	if (bi->i_sblock)
7e46aa5c AV	201	info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
1da177e4	202	info->si_freei++;
fac92bec	203	clear_bit(ino, info->si_imap);
1da177e4	204	dump_imap("delete_inode", s);
fac92bec	205	}
1da177e4	206
f433dc56 DV	207	/*
	208	* If this was the last file, make the previous block
	209	* "last block of the last file" even if there is no
	210	* real file there, saves us 1 gap.
	211	*/
	212	if (info->si_lf_eblk == bi->i_eblock) {
	213	info->si_lf_eblk = bi->i_sblock - 1;
1da177e4 LT	214	mark_buffer_dirty(info->si_sbh);
1da177e4 LT	215	}
3f165e4c	216	mutex_unlock(&info->bfs_lock);
1da177e4 LT	217	clear_inode(inode);
	218	}
	219
561e47ce CH	220	static int bfs_sync_fs(struct super_block *sb, int wait)
	221	{
	222	struct bfs_sb_info *info = BFS_SB(sb);
	223
	224	mutex_lock(&info->bfs_lock);
	225	mark_buffer_dirty(info->si_sbh);
	226	sb->s_dirt = 0;
	227	mutex_unlock(&info->bfs_lock);
	228
	229	return 0;
	230	}
	231
	232	static void bfs_write_super(struct super_block *sb)
	233	{
	234	if (!(sb->s_flags & MS_RDONLY))
	235	bfs_sync_fs(sb, 1);
	236	else
	237	sb->s_dirt = 0;
	238	}
	239
1da177e4 LT	240	static void bfs_put_super(struct super_block *s)
	241	{
	242	struct bfs_sb_info *info = BFS_SB(s);
3f165e4c	243
e1f89ec9 ES	244	if (!info)
	245	return;
	246
6cfd0148 CH	247	lock_kernel();
6cfd0148 CH	248
8c85e125 CH	249	if (s->s_dirt)
	250	bfs_write_super(s);
	251
1da177e4	252	brelse(info->si_sbh);
3f165e4c	253	mutex_destroy(&info->bfs_lock);
1da177e4 LT	254	kfree(info->si_imap);
	255	kfree(info);
	256	s->s_fs_info = NULL;
6cfd0148 CH	257
6cfd0148 CH	258	unlock_kernel();
1da177e4 LT	259	}
1da177e4 LT	260
726c3342	261	static int bfs_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4	262	{
726c3342	263	struct super_block *s = dentry->d_sb;
1da177e4 LT	264	struct bfs_sb_info *info = BFS_SB(s);
	265	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
	266	buf->f_type = BFS_MAGIC;
	267	buf->f_bsize = s->s_blocksize;
	268	buf->f_blocks = info->si_blocks;
	269	buf->f_bfree = buf->f_bavail = info->si_freeb;
	270	buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
	271	buf->f_ffree = info->si_freei;
	272	buf->f_fsid.val[0] = (u32)id;
	273	buf->f_fsid.val[1] = (u32)(id >> 32);
	274	buf->f_namelen = BFS_NAMELEN;
	275	return 0;
	276	}
	277
f433dc56	278	static struct kmem_cache *bfs_inode_cachep;
1da177e4 LT	279
	280	static struct inode bfs_alloc_inode(struct super_block sb)
	281	{
	282	struct bfs_inode_info *bi;
e94b1766	283	bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
1da177e4 LT	284	if (!bi)
	285	return NULL;
	286	return &bi->vfs_inode;
	287	}
	288
	289	static void bfs_destroy_inode(struct inode *inode)
	290	{
	291	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
	292	}
	293
51cc5068	294	static void init_once(void *foo)
1da177e4 LT	295	{
	296	struct bfs_inode_info *bi = foo;
	297
a35afb83	298	inode_init_once(&bi->vfs_inode);
1da177e4	299	}
20c2df83	300
1da177e4 LT	301	static int init_inodecache(void)
	302	{
	303	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
	304	sizeof(struct bfs_inode_info),
fffb60f9 PJ	305	0, (SLAB_RECLAIM_ACCOUNT\|
fffb60f9 PJ	306	SLAB_MEM_SPREAD),
20c2df83	307	init_once);
1da177e4 LT	308	if (bfs_inode_cachep == NULL)
	309	return -ENOMEM;
	310	return 0;
	311	}
	312
	313	static void destroy_inodecache(void)
	314	{
1a1d92c1	315	kmem_cache_destroy(bfs_inode_cachep);
1da177e4 LT	316	}
1da177e4 LT	317
ee9b6d61	318	static const struct super_operations bfs_sops = {
1da177e4 LT	319	.alloc_inode = bfs_alloc_inode,
1da177e4 LT	320	.destroy_inode = bfs_destroy_inode,
1da177e4 LT	321	.write_inode = bfs_write_inode,
	322	.delete_inode = bfs_delete_inode,
	323	.put_super = bfs_put_super,
	324	.write_super = bfs_write_super,
561e47ce	325	.sync_fs = bfs_sync_fs,
1da177e4 LT	326	.statfs = bfs_statfs,
	327	};
	328
f433dc56	329	void dump_imap(const char prefix, struct super_block s)
1da177e4	330	{
fac92bec	331	#ifdef DEBUG
1da177e4 LT	332	int i;
	333	char tmpbuf = (char )get_zeroed_page(GFP_KERNEL);
	334
	335	if (!tmpbuf)
	336	return;
f433dc56 DV	337	for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
f433dc56 DV	338	if (i > PAGE_SIZE - 100) break;
1da177e4 LT	339	if (test_bit(i, BFS_SB(s)->si_imap))
	340	strcat(tmpbuf, "1");
	341	else
	342	strcat(tmpbuf, "0");
	343	}
f433dc56 DV	344	printf("BFS-fs: %s: lasti=%08lx <%s>\n",
f433dc56 DV	345	prefix, BFS_SB(s)->si_lasti, tmpbuf);
1da177e4 LT	346	free_page((unsigned long)tmpbuf);
	347	#endif
	348	}
	349
	350	static int bfs_fill_super(struct super_block s, void data, int silent)
	351	{
f433dc56 DV	352	struct buffer_head *bh;
	353	struct bfs_super_block *bfs_sb;
	354	struct inode *inode;
fac92bec	355	unsigned i, imap_len;
f433dc56	356	struct bfs_sb_info *info;
5998649f	357	int ret = -EINVAL;
e1f89ec9	358	unsigned long i_sblock, i_eblock, i_eoff, s_size;
1da177e4	359
f8314dc6	360	info = kzalloc(sizeof(*info), GFP_KERNEL);
1da177e4 LT	361	if (!info)
1da177e4 LT	362	return -ENOMEM;
5998649f	363	mutex_init(&info->bfs_lock);
1da177e4	364	s->s_fs_info = info;
1da177e4 LT	365
	366	sb_set_blocksize(s, BFS_BSIZE);
	367
5998649f AV	368	info->si_sbh = sb_bread(s, 0);
5998649f AV	369	if (!info->si_sbh)
1da177e4	370	goto out;
5998649f	371	bfs_sb = (struct bfs_super_block *)info->si_sbh->b_data;
fac92bec	372	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
1da177e4 LT	373	if (!silent)
1da177e4 LT	374	printf("No BFS filesystem on %s (magic=%08x)\n",
fac92bec	375	s->s_id, le32_to_cpu(bfs_sb->s_magic));
5998649f	376	goto out1;
1da177e4 LT	377	}
	378	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
	379	printf("%s is unclean, continuing\n", s->s_id);
	380
	381	s->s_magic = BFS_MAGIC;
e1f89ec9 ES	382
	383	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) {
	384	printf("Superblock is corrupted\n");
5998649f	385	goto out1;
e1f89ec9 ES	386	}
e1f89ec9 ES	387
f433dc56 DV	388	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
	389	sizeof(struct bfs_inode)
	390	+ BFS_ROOT_INO - 1;
	391	imap_len = (info->si_lasti / 8) + 1;
f8314dc6	392	info->si_imap = kzalloc(imap_len, GFP_KERNEL);
1da177e4	393	if (!info->si_imap)
5998649f	394	goto out1;
f433dc56	395	for (i = 0; i < BFS_ROOT_INO; i++)
1da177e4 LT	396	set_bit(i, info->si_imap);
	397
	398	s->s_op = &bfs_sops;
e33ab086 DH	399	inode = bfs_iget(s, BFS_ROOT_INO);
	400	if (IS_ERR(inode)) {
	401	ret = PTR_ERR(inode);
5998649f	402	goto out2;
1da177e4 LT	403	}
	404	s->s_root = d_alloc_root(inode);
	405	if (!s->s_root) {
	406	iput(inode);
e33ab086	407	ret = -ENOMEM;
5998649f	408	goto out2;
1da177e4 LT	409	}
1da177e4 LT	410
f433dc56 DV	411	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
	412	info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1
	413	- le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
1da177e4 LT	414	info->si_freei = 0;
1da177e4 LT	415	info->si_lf_eblk = 0;
50682bb4 ES	416
	417	/* can we read the last block? */
	418	bh = sb_bread(s, info->si_blocks - 1);
	419	if (!bh) {
	420	printf("Last block not available: %lu\n", info->si_blocks - 1);
50682bb4	421	ret = -EIO;
5998649f	422	goto out3;
50682bb4 ES	423	}
	424	brelse(bh);
	425
c2b513df	426	bh = NULL;
f433dc56	427	for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
c2b513df	428	struct bfs_inode *di;
f433dc56	429	int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
c2b513df	430	int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
75b25b4c	431	unsigned long eblock;
c2b513df AV	432
	433	if (!off) {
	434	brelse(bh);
	435	bh = sb_bread(s, block);
	436	}
	437
	438	if (!bh)
	439	continue;
	440
	441	di = (struct bfs_inode *)bh->b_data + off;
	442
e1f89ec9 ES	443	/* test if filesystem is not corrupted */
	444
	445	i_eoff = le32_to_cpu(di->i_eoffset);
	446	i_sblock = le32_to_cpu(di->i_sblock);
	447	i_eblock = le32_to_cpu(di->i_eblock);
	448	s_size = le32_to_cpu(bfs_sb->s_end);
	449
	450	if (i_sblock > info->si_blocks \|\|
	451	i_eblock > info->si_blocks \|\|
	452	i_sblock > i_eblock \|\|
	453	i_eoff > s_size \|\|
	454	i_sblock * BFS_BSIZE > i_eoff) {
	455
	456	printf("Inode 0x%08x corrupted\n", i);
	457
	458	brelse(bh);
5998649f AV	459	ret = -EIO;
5998649f AV	460	goto out3;
e1f89ec9 ES	461	}
e1f89ec9 ES	462
c2b513df	463	if (!di->i_ino) {
1da177e4	464	info->si_freei++;
c2b513df AV	465	continue;
	466	}
	467	set_bit(i, info->si_imap);
	468	info->si_freeb -= BFS_FILEBLOCKS(di);
	469
c2b513df	470	eblock = le32_to_cpu(di->i_eblock);
f433dc56	471	if (eblock > info->si_lf_eblk)
c2b513df	472	info->si_lf_eblk = eblock;
1da177e4	473	}
c2b513df	474	brelse(bh);
1da177e4	475	if (!(s->s_flags & MS_RDONLY)) {
c2b513df	476	mark_buffer_dirty(info->si_sbh);
1da177e4 LT	477	s->s_dirt = 1;
	478	}
	479	dump_imap("read_super", s);
	480	return 0;
	481
5998649f AV	482	out3:
	483	dput(s->s_root);
	484	s->s_root = NULL;
	485	out2:
	486	kfree(info->si_imap);
	487	out1:
	488	brelse(info->si_sbh);
1da177e4	489	out:
5998649f	490	mutex_destroy(&info->bfs_lock);
1da177e4 LT	491	kfree(info);
1da177e4 LT	492	s->s_fs_info = NULL;
e33ab086	493	return ret;
1da177e4 LT	494	}
1da177e4 LT	495
454e2398 DH	496	static int bfs_get_sb(struct file_system_type *fs_type,
454e2398 DH	497	int flags, const char dev_name, void data, struct vfsmount *mnt)
1da177e4	498	{
454e2398	499	return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt);
1da177e4 LT	500	}
	501
	502	static struct file_system_type bfs_fs_type = {
	503	.owner = THIS_MODULE,
	504	.name = "bfs",
	505	.get_sb = bfs_get_sb,
	506	.kill_sb = kill_block_super,
	507	.fs_flags = FS_REQUIRES_DEV,
	508	};
	509
	510	static int __init init_bfs_fs(void)
	511	{
	512	int err = init_inodecache();
	513	if (err)
	514	goto out1;
	515	err = register_filesystem(&bfs_fs_type);
	516	if (err)
	517	goto out;
	518	return 0;
	519	out:
	520	destroy_inodecache();
	521	out1:
	522	return err;
	523	}
	524
	525	static void __exit exit_bfs_fs(void)
	526	{
	527	unregister_filesystem(&bfs_fs_type);
	528	destroy_inodecache();
	529	}
	530
	531	module_init(init_bfs_fs)
	532	module_exit(exit_bfs_fs)