[deliverable/linux.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/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

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->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 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->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_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("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;
	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->si_imap);
	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.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_i_callback(struct rcu_head *head)
{
	struct inode *inode = container_of(head, struct inode, i_rcu);
	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
}

static void bfs_destroy_inode(struct inode *inode)
{
	call_rcu(&inode->i_rcu, bfs_i_callback);
}

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_MEM_SPREAD),
					     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,
	.destroy_inode	= bfs_destroy_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("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, *sbh;
	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);

	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)) {
		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_make_root(inode);
	if (!s->s_root) {
		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);
	brelse(sbh);
	bfs_dump_imap("read_super", s);
	return 0;

out3:
	dput(s->s_root);
	s->s_root = NULL;
out2:
	kfree(info->si_imap);
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
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>
1da177e4 LT	15	#include <linux/buffer_head.h>
1da177e4 LT	16	#include <linux/vfs.h>
a9185b41	17	#include <linux/writeback.h>
1da177e4 LT	18	#include <asm/uaccess.h>
	19	#include "bfs.h"
	20
69688262	21	MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
1da177e4 LT	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
e33ab086	33	struct inode bfs_iget(struct super_block sb, unsigned long ino)
1da177e4	34	{
f433dc56	35	struct bfs_inode *di;
e33ab086	36	struct inode *inode;
f433dc56	37	struct buffer_head *bh;
1da177e4 LT	38	int block, off;
1da177e4 LT	39
e33ab086	40	inode = iget_locked(sb, ino);
821ff77c	41	if (!inode)
e33ab086 DH	42	return ERR_PTR(-ENOMEM);
	43	if (!(inode->i_state & I_NEW))
	44	return inode;
	45
f433dc56	46	if ((ino < BFS_ROOT_INO) \|\| (ino > BFS_SB(inode->i_sb)->si_lasti)) {
1da177e4	47	printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
e33ab086	48	goto error;
1da177e4 LT	49	}
1da177e4 LT	50
f433dc56	51	block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
1da177e4 LT	52	bh = sb_bread(inode->i_sb, block);
1da177e4 LT	53	if (!bh) {
f433dc56 DV	54	printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
f433dc56 DV	55	ino);
e33ab086	56	goto error;
1da177e4 LT	57	}
	58
	59	off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
	60	di = (struct bfs_inode *)bh->b_data + off;
	61
f433dc56	62	inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
fac92bec	63	if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
1da177e4 LT	64	inode->i_mode \|= S_IFDIR;
	65	inode->i_op = &bfs_dir_inops;
	66	inode->i_fop = &bfs_dir_operations;
fac92bec	67	} else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
1da177e4 LT	68	inode->i_mode \|= S_IFREG;
	69	inode->i_op = &bfs_file_inops;
	70	inode->i_fop = &bfs_file_operations;
	71	inode->i_mapping->a_ops = &bfs_aops;
	72	}
	73
fac92bec AS	74	BFS_I(inode)->i_sblock = le32_to_cpu(di->i_sblock);
fac92bec AS	75	BFS_I(inode)->i_eblock = le32_to_cpu(di->i_eblock);
f433dc56	76	BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
7f5b82b8 EB	77	i_uid_write(inode, le32_to_cpu(di->i_uid));
7f5b82b8 EB	78	i_gid_write(inode, le32_to_cpu(di->i_gid));
bfe86848	79	set_nlink(inode, le32_to_cpu(di->i_nlink));
1da177e4 LT	80	inode->i_size = BFS_FILESIZE(di);
1da177e4 LT	81	inode->i_blocks = BFS_FILEBLOCKS(di);
fac92bec AS	82	inode->i_atime.tv_sec = le32_to_cpu(di->i_atime);
	83	inode->i_mtime.tv_sec = le32_to_cpu(di->i_mtime);
	84	inode->i_ctime.tv_sec = le32_to_cpu(di->i_ctime);
1da177e4 LT	85	inode->i_atime.tv_nsec = 0;
	86	inode->i_mtime.tv_nsec = 0;
	87	inode->i_ctime.tv_nsec = 0;
1da177e4 LT	88
1da177e4 LT	89	brelse(bh);
e33ab086 DH	90	unlock_new_inode(inode);
	91	return inode;
	92
	93	error:
	94	iget_failed(inode);
	95	return ERR_PTR(-EIO);
1da177e4 LT	96	}
1da177e4 LT	97
9df2f851 AV	98	static struct bfs_inode find_inode(struct super_block sb, u16 ino, struct buffer_head **p)
	99	{
	100	if ((ino < BFS_ROOT_INO) \|\| (ino > BFS_SB(sb)->si_lasti)) {
	101	printf("Bad inode number %s:%08x\n", sb->s_id, ino);
	102	return ERR_PTR(-EIO);
	103	}
	104
	105	ino -= BFS_ROOT_INO;
	106
	107	*p = sb_bread(sb, 1 + ino / BFS_INODES_PER_BLOCK);
	108	if (!*p) {
	109	printf("Unable to read inode %s:%08x\n", sb->s_id, ino);
	110	return ERR_PTR(-EIO);
	111	}
	112
	113	return (struct bfs_inode )(p)->b_data + ino % BFS_INODES_PER_BLOCK;
	114	}
	115
a9185b41	116	static int bfs_write_inode(struct inode inode, struct writeback_control wbc)
1da177e4	117	{
4427f0c3	118	struct bfs_sb_info *info = BFS_SB(inode->i_sb);
fac92bec AS	119	unsigned int ino = (u16)inode->i_ino;
fac92bec AS	120	unsigned long i_sblock;
f433dc56 DV	121	struct bfs_inode *di;
f433dc56 DV	122	struct buffer_head *bh;
4427f0c3	123	int err = 0;
1da177e4	124
fac92bec AS	125	dprintf("ino=%08x\n", ino);
fac92bec AS	126
9df2f851 AV	127	di = find_inode(inode->i_sb, ino, &bh);
	128	if (IS_ERR(di))
	129	return PTR_ERR(di);
1da177e4	130
3f165e4c	131	mutex_lock(&info->bfs_lock);
1da177e4	132
fac92bec AS	133	if (ino == BFS_ROOT_INO)
fac92bec AS	134	di->i_vtype = cpu_to_le32(BFS_VDIR);
1da177e4	135	else
fac92bec AS	136	di->i_vtype = cpu_to_le32(BFS_VREG);
	137
	138	di->i_ino = cpu_to_le16(ino);
	139	di->i_mode = cpu_to_le32(inode->i_mode);
7f5b82b8 EB	140	di->i_uid = cpu_to_le32(i_uid_read(inode));
7f5b82b8 EB	141	di->i_gid = cpu_to_le32(i_gid_read(inode));
fac92bec AS	142	di->i_nlink = cpu_to_le32(inode->i_nlink);
	143	di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
	144	di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
	145	di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
	146	i_sblock = BFS_I(inode)->i_sblock;
	147	di->i_sblock = cpu_to_le32(i_sblock);
	148	di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
	149	di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
1da177e4 LT	150
1da177e4 LT	151	mark_buffer_dirty(bh);
a9185b41	152	if (wbc->sync_mode == WB_SYNC_ALL) {
4427f0c3 AV	153	sync_dirty_buffer(bh);
	154	if (buffer_req(bh) && !buffer_uptodate(bh))
	155	err = -EIO;
	156	}
1da177e4	157	brelse(bh);
3f165e4c	158	mutex_unlock(&info->bfs_lock);
4427f0c3	159	return err;
1da177e4 LT	160	}
1da177e4 LT	161
9df2f851	162	static void bfs_evict_inode(struct inode *inode)
1da177e4 LT	163	{
1da177e4 LT	164	unsigned long ino = inode->i_ino;
f433dc56 DV	165	struct bfs_inode *di;
f433dc56 DV	166	struct buffer_head *bh;
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
91b0abe3	173	truncate_inode_pages_final(&inode->i_data);
9df2f851	174	invalidate_inode_buffers(inode);
dbd5768f	175	clear_inode(inode);
fef26658	176
9df2f851	177	if (inode->i_nlink)
1da177e4	178	return;
f433dc56	179
9df2f851 AV	180	di = find_inode(s, inode->i_ino, &bh);
9df2f851 AV	181	if (IS_ERR(di))
1da177e4	182	return;
9df2f851 AV	183
	184	mutex_lock(&info->bfs_lock);
	185	/* clear on-disk inode */
	186	memset(di, 0, sizeof(struct bfs_inode));
f433dc56 DV	187	mark_buffer_dirty(bh);
	188	brelse(bh);
	189
fac92bec	190	if (bi->i_dsk_ino) {
7e46aa5c AV	191	if (bi->i_sblock)
7e46aa5c AV	192	info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
1da177e4	193	info->si_freei++;
fac92bec	194	clear_bit(ino, info->si_imap);
1da85fdf	195	bfs_dump_imap("delete_inode", s);
fac92bec	196	}
1da177e4	197
f433dc56 DV	198	/*
	199	* If this was the last file, make the previous block
	200	* "last block of the last file" even if there is no
	201	* real file there, saves us 1 gap.
	202	*/
4e29d50a	203	if (info->si_lf_eblk == bi->i_eblock)
f433dc56	204	info->si_lf_eblk = bi->i_sblock - 1;
3f165e4c	205	mutex_unlock(&info->bfs_lock);
1da177e4 LT	206	}
	207
	208	static void bfs_put_super(struct super_block *s)
	209	{
	210	struct bfs_sb_info *info = BFS_SB(s);
3f165e4c	211
e1f89ec9 ES	212	if (!info)
	213	return;
	214
3f165e4c	215	mutex_destroy(&info->bfs_lock);
1da177e4 LT	216	kfree(info->si_imap);
	217	kfree(info);
	218	s->s_fs_info = NULL;
	219	}
	220
726c3342	221	static int bfs_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4	222	{
726c3342	223	struct super_block *s = dentry->d_sb;
1da177e4 LT	224	struct bfs_sb_info *info = BFS_SB(s);
	225	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
	226	buf->f_type = BFS_MAGIC;
	227	buf->f_bsize = s->s_blocksize;
	228	buf->f_blocks = info->si_blocks;
	229	buf->f_bfree = buf->f_bavail = info->si_freeb;
	230	buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
	231	buf->f_ffree = info->si_freei;
	232	buf->f_fsid.val[0] = (u32)id;
	233	buf->f_fsid.val[1] = (u32)(id >> 32);
	234	buf->f_namelen = BFS_NAMELEN;
	235	return 0;
	236	}
	237
f433dc56	238	static struct kmem_cache *bfs_inode_cachep;
1da177e4 LT	239
	240	static struct inode bfs_alloc_inode(struct super_block sb)
	241	{
	242	struct bfs_inode_info *bi;
e94b1766	243	bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
1da177e4 LT	244	if (!bi)
	245	return NULL;
	246	return &bi->vfs_inode;
	247	}
	248
fa0d7e3d	249	static void bfs_i_callback(struct rcu_head *head)
1da177e4	250	{
fa0d7e3d	251	struct inode *inode = container_of(head, struct inode, i_rcu);
1da177e4 LT	252	kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
	253	}
	254
fa0d7e3d NP	255	static void bfs_destroy_inode(struct inode *inode)
	256	{
	257	call_rcu(&inode->i_rcu, bfs_i_callback);
	258	}
	259
51cc5068	260	static void init_once(void *foo)
1da177e4 LT	261	{
	262	struct bfs_inode_info *bi = foo;
	263
a35afb83	264	inode_init_once(&bi->vfs_inode);
1da177e4	265	}
20c2df83	266
758b4440	267	static int __init init_inodecache(void)
1da177e4 LT	268	{
	269	bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
	270	sizeof(struct bfs_inode_info),
fffb60f9 PJ	271	0, (SLAB_RECLAIM_ACCOUNT\|
fffb60f9 PJ	272	SLAB_MEM_SPREAD),
20c2df83	273	init_once);
1da177e4 LT	274	if (bfs_inode_cachep == NULL)
	275	return -ENOMEM;
	276	return 0;
	277	}
	278
	279	static void destroy_inodecache(void)
	280	{
8c0a8537 KS	281	/*
	282	* Make sure all delayed rcu free inodes are flushed before we
	283	* destroy cache.
	284	*/
	285	rcu_barrier();
1a1d92c1	286	kmem_cache_destroy(bfs_inode_cachep);
1da177e4 LT	287	}
1da177e4 LT	288
ee9b6d61	289	static const struct super_operations bfs_sops = {
1da177e4 LT	290	.alloc_inode = bfs_alloc_inode,
1da177e4 LT	291	.destroy_inode = bfs_destroy_inode,
1da177e4	292	.write_inode = bfs_write_inode,
9df2f851	293	.evict_inode = bfs_evict_inode,
1da177e4	294	.put_super = bfs_put_super,
1da177e4 LT	295	.statfs = bfs_statfs,
	296	};
	297
1da85fdf	298	void bfs_dump_imap(const char prefix, struct super_block s)
1da177e4	299	{
fac92bec	300	#ifdef DEBUG
1da177e4 LT	301	int i;
	302	char tmpbuf = (char )get_zeroed_page(GFP_KERNEL);
	303
	304	if (!tmpbuf)
	305	return;
f433dc56 DV	306	for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
f433dc56 DV	307	if (i > PAGE_SIZE - 100) break;
1da177e4 LT	308	if (test_bit(i, BFS_SB(s)->si_imap))
	309	strcat(tmpbuf, "1");
	310	else
	311	strcat(tmpbuf, "0");
	312	}
f433dc56 DV	313	printf("BFS-fs: %s: lasti=%08lx <%s>\n",
f433dc56 DV	314	prefix, BFS_SB(s)->si_lasti, tmpbuf);
1da177e4 LT	315	free_page((unsigned long)tmpbuf);
	316	#endif
	317	}
	318
	319	static int bfs_fill_super(struct super_block s, void data, int silent)
	320	{
4e29d50a	321	struct buffer_head bh, sbh;
f433dc56 DV	322	struct bfs_super_block *bfs_sb;
f433dc56 DV	323	struct inode *inode;
fac92bec	324	unsigned i, imap_len;
f433dc56	325	struct bfs_sb_info *info;
5998649f	326	int ret = -EINVAL;
e1f89ec9	327	unsigned long i_sblock, i_eblock, i_eoff, s_size;
1da177e4	328
f8314dc6	329	info = kzalloc(sizeof(*info), GFP_KERNEL);
ba13d597	330	if (!info)
1da177e4	331	return -ENOMEM;
5998649f	332	mutex_init(&info->bfs_lock);
1da177e4	333	s->s_fs_info = info;
1da177e4 LT	334
	335	sb_set_blocksize(s, BFS_BSIZE);
	336
4e29d50a AB	337	sbh = sb_bread(s, 0);
4e29d50a AB	338	if (!sbh)
1da177e4	339	goto out;
4e29d50a	340	bfs_sb = (struct bfs_super_block *)sbh->b_data;
fac92bec	341	if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
1da177e4 LT	342	if (!silent)
1da177e4 LT	343	printf("No BFS filesystem on %s (magic=%08x)\n",
fac92bec	344	s->s_id, le32_to_cpu(bfs_sb->s_magic));
5998649f	345	goto out1;
1da177e4 LT	346	}
	347	if (BFS_UNCLEAN(bfs_sb, s) && !silent)
	348	printf("%s is unclean, continuing\n", s->s_id);
	349
	350	s->s_magic = BFS_MAGIC;
e1f89ec9 ES	351
	352	if (le32_to_cpu(bfs_sb->s_start) > le32_to_cpu(bfs_sb->s_end)) {
	353	printf("Superblock is corrupted\n");
5998649f	354	goto out1;
e1f89ec9 ES	355	}
e1f89ec9 ES	356
f433dc56 DV	357	info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
	358	sizeof(struct bfs_inode)
	359	+ BFS_ROOT_INO - 1;
	360	imap_len = (info->si_lasti / 8) + 1;
f8314dc6	361	info->si_imap = kzalloc(imap_len, GFP_KERNEL);
1da177e4	362	if (!info->si_imap)
5998649f	363	goto out1;
f433dc56	364	for (i = 0; i < BFS_ROOT_INO; i++)
1da177e4 LT	365	set_bit(i, info->si_imap);
	366
	367	s->s_op = &bfs_sops;
e33ab086 DH	368	inode = bfs_iget(s, BFS_ROOT_INO);
	369	if (IS_ERR(inode)) {
	370	ret = PTR_ERR(inode);
5998649f	371	goto out2;
1da177e4	372	}
48fde701	373	s->s_root = d_make_root(inode);
1da177e4	374	if (!s->s_root) {
e33ab086	375	ret = -ENOMEM;
5998649f	376	goto out2;
1da177e4 LT	377	}
1da177e4 LT	378
f433dc56 DV	379	info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
	380	info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1
	381	- le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
1da177e4 LT	382	info->si_freei = 0;
1da177e4 LT	383	info->si_lf_eblk = 0;
50682bb4 ES	384
	385	/* can we read the last block? */
	386	bh = sb_bread(s, info->si_blocks - 1);
	387	if (!bh) {
	388	printf("Last block not available: %lu\n", info->si_blocks - 1);
50682bb4	389	ret = -EIO;
5998649f	390	goto out3;
50682bb4 ES	391	}
	392	brelse(bh);
	393
c2b513df	394	bh = NULL;
f433dc56	395	for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
c2b513df	396	struct bfs_inode *di;
f433dc56	397	int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
c2b513df	398	int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
75b25b4c	399	unsigned long eblock;
c2b513df AV	400
	401	if (!off) {
	402	brelse(bh);
	403	bh = sb_bread(s, block);
	404	}
	405
	406	if (!bh)
	407	continue;
	408
	409	di = (struct bfs_inode *)bh->b_data + off;
	410
e1f89ec9 ES	411	/* test if filesystem is not corrupted */
	412
	413	i_eoff = le32_to_cpu(di->i_eoffset);
	414	i_sblock = le32_to_cpu(di->i_sblock);
	415	i_eblock = le32_to_cpu(di->i_eblock);
	416	s_size = le32_to_cpu(bfs_sb->s_end);
	417
	418	if (i_sblock > info->si_blocks \|\|
	419	i_eblock > info->si_blocks \|\|
	420	i_sblock > i_eblock \|\|
	421	i_eoff > s_size \|\|
	422	i_sblock * BFS_BSIZE > i_eoff) {
	423
	424	printf("Inode 0x%08x corrupted\n", i);
	425
	426	brelse(bh);
5998649f AV	427	ret = -EIO;
5998649f AV	428	goto out3;
e1f89ec9 ES	429	}
e1f89ec9 ES	430
c2b513df	431	if (!di->i_ino) {
1da177e4	432	info->si_freei++;
c2b513df AV	433	continue;
	434	}
	435	set_bit(i, info->si_imap);
	436	info->si_freeb -= BFS_FILEBLOCKS(di);
	437
c2b513df	438	eblock = le32_to_cpu(di->i_eblock);
f433dc56	439	if (eblock > info->si_lf_eblk)
c2b513df	440	info->si_lf_eblk = eblock;
1da177e4	441	}
c2b513df	442	brelse(bh);
4e29d50a	443	brelse(sbh);
1da85fdf	444	bfs_dump_imap("read_super", s);
1da177e4 LT	445	return 0;
1da177e4 LT	446
5998649f AV	447	out3:
	448	dput(s->s_root);
	449	s->s_root = NULL;
	450	out2:
	451	kfree(info->si_imap);
	452	out1:
4e29d50a	453	brelse(sbh);
1da177e4	454	out:
5998649f	455	mutex_destroy(&info->bfs_lock);
1da177e4 LT	456	kfree(info);
1da177e4 LT	457	s->s_fs_info = NULL;
e33ab086	458	return ret;
1da177e4 LT	459	}
1da177e4 LT	460
152a0836 AV	461	static struct dentry bfs_mount(struct file_system_type fs_type,
152a0836 AV	462	int flags, const char dev_name, void data)
1da177e4	463	{
152a0836	464	return mount_bdev(fs_type, flags, dev_name, data, bfs_fill_super);
1da177e4 LT	465	}
	466
	467	static struct file_system_type bfs_fs_type = {
	468	.owner = THIS_MODULE,
	469	.name = "bfs",
152a0836	470	.mount = bfs_mount,
1da177e4 LT	471	.kill_sb = kill_block_super,
	472	.fs_flags = FS_REQUIRES_DEV,
	473	};
7f78e035	474	MODULE_ALIAS_FS("bfs");
1da177e4 LT	475
	476	static int __init init_bfs_fs(void)
	477	{
	478	int err = init_inodecache();
	479	if (err)
	480	goto out1;
	481	err = register_filesystem(&bfs_fs_type);
	482	if (err)
	483	goto out;
	484	return 0;
	485	out:
	486	destroy_inodecache();
	487	out1:
	488	return err;
	489	}
	490
	491	static void __exit exit_bfs_fs(void)
	492	{
	493	unregister_filesystem(&bfs_fs_type);
	494	destroy_inodecache();
	495	}
	496
	497	module_init(init_bfs_fs)
	498	module_exit(exit_bfs_fs)