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

/*
 * Optimized MPEG FS - inode and super operations.
 * Copyright (C) 2006 Bob Copeland <me@bobcopeland.com>
 * Released under GPL v2.
 */
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/vfs.h>
#include <linux/parser.h>
#include <linux/buffer_head.h>
#include <linux/vmalloc.h>
#include <linux/writeback.h>
#include <linux/crc-itu-t.h>
#include "omfs.h"

MODULE_AUTHOR("Bob Copeland <me@bobcopeland.com>");
MODULE_DESCRIPTION("OMFS (ReplayTV/Karma) Filesystem for Linux");
MODULE_LICENSE("GPL");

struct inode *omfs_new_inode(struct inode *dir, int mode)
{
	struct inode *inode;
	u64 new_block;
	int err;
	int len;
	struct omfs_sb_info *sbi = OMFS_SB(dir->i_sb);

	inode = new_inode(dir->i_sb);
	if (!inode)
		return ERR_PTR(-ENOMEM);

	err = omfs_allocate_range(dir->i_sb, sbi->s_mirrors, sbi->s_mirrors,
			&new_block, &len);
	if (err)
		goto fail;

	inode->i_ino = new_block;
	inode->i_mode = mode;
	inode->i_uid = current_fsuid();
	inode->i_gid = current_fsgid();
	inode->i_mapping->a_ops = &omfs_aops;

	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	switch (mode & S_IFMT) {
	case S_IFDIR:
		inode->i_op = &omfs_dir_inops;
		inode->i_fop = &omfs_dir_operations;
		inode->i_size = sbi->s_sys_blocksize;
		inc_nlink(inode);
		break;
	case S_IFREG:
		inode->i_op = &omfs_file_inops;
		inode->i_fop = &omfs_file_operations;
		inode->i_size = 0;
		break;
	}

	insert_inode_hash(inode);
	mark_inode_dirty(inode);
	return inode;
fail:
	make_bad_inode(inode);
	iput(inode);
	return ERR_PTR(err);
}

/*
 * Update the header checksums for a dirty inode based on its contents.
 * Caller is expected to hold the buffer head underlying oi and mark it
 * dirty.
 */
static void omfs_update_checksums(struct omfs_inode *oi)
{
	int xor, i, ofs = 0, count;
	u16 crc = 0;
	unsigned char *ptr = (unsigned char *) oi;

	count = be32_to_cpu(oi->i_head.h_body_size);
	ofs = sizeof(struct omfs_header);

	crc = crc_itu_t(crc, ptr + ofs, count);
	oi->i_head.h_crc = cpu_to_be16(crc);

	xor = ptr[0];
	for (i = 1; i < OMFS_XOR_COUNT; i++)
		xor ^= ptr[i];

	oi->i_head.h_check_xor = xor;
}

static int __omfs_write_inode(struct inode *inode, int wait)
{
	struct omfs_inode *oi;
	struct omfs_sb_info *sbi = OMFS_SB(inode->i_sb);
	struct buffer_head *bh, *bh2;
	unsigned int block;
	u64 ctime;
	int i;
	int ret = -EIO;
	int sync_failed = 0;

	/* get current inode since we may have written sibling ptrs etc. */
	block = clus_to_blk(sbi, inode->i_ino);
	bh = sb_bread(inode->i_sb, block);
	if (!bh)
		goto out;

	oi = (struct omfs_inode *) bh->b_data;

	oi->i_head.h_self = cpu_to_be64(inode->i_ino);
	if (S_ISDIR(inode->i_mode))
		oi->i_type = OMFS_DIR;
	else if (S_ISREG(inode->i_mode))
		oi->i_type = OMFS_FILE;
	else {
		printk(KERN_WARNING "omfs: unknown file type: %d\n",
			inode->i_mode);
		goto out_brelse;
	}

	oi->i_head.h_body_size = cpu_to_be32(sbi->s_sys_blocksize -
		sizeof(struct omfs_header));
	oi->i_head.h_version = 1;
	oi->i_head.h_type = OMFS_INODE_NORMAL;
	oi->i_head.h_magic = OMFS_IMAGIC;
	oi->i_size = cpu_to_be64(inode->i_size);

	ctime = inode->i_ctime.tv_sec * 1000LL +
		((inode->i_ctime.tv_nsec + 999)/1000);
	oi->i_ctime = cpu_to_be64(ctime);

	omfs_update_checksums(oi);

	mark_buffer_dirty(bh);
	if (wait) {
		sync_dirty_buffer(bh);
		if (buffer_req(bh) && !buffer_uptodate(bh))
			sync_failed = 1;
	}

	/* if mirroring writes, copy to next fsblock */
	for (i = 1; i < sbi->s_mirrors; i++) {
		bh2 = sb_bread(inode->i_sb, block + i *
			(sbi->s_blocksize / sbi->s_sys_blocksize));
		if (!bh2)
			goto out_brelse;

		memcpy(bh2->b_data, bh->b_data, bh->b_size);
		mark_buffer_dirty(bh2);
		if (wait) {
			sync_dirty_buffer(bh2);
			if (buffer_req(bh2) && !buffer_uptodate(bh2))
				sync_failed = 1;
		}
		brelse(bh2);
	}
	ret = (sync_failed) ? -EIO : 0;
out_brelse:
	brelse(bh);
out:
	return ret;
}

static int omfs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
	return __omfs_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
}

int omfs_sync_inode(struct inode *inode)
{
	return __omfs_write_inode(inode, 1);
}

/*
 * called when an entry is deleted, need to clear the bits in the
 * bitmaps.
 */
static void omfs_delete_inode(struct inode *inode)
{
	truncate_inode_pages(&inode->i_data, 0);

	if (S_ISREG(inode->i_mode)) {
		inode->i_size = 0;
		omfs_shrink_inode(inode);
	}

	omfs_clear_range(inode->i_sb, inode->i_ino, 2);
	clear_inode(inode);
}

struct inode *omfs_iget(struct super_block *sb, ino_t ino)
{
	struct omfs_sb_info *sbi = OMFS_SB(sb);
	struct omfs_inode *oi;
	struct buffer_head *bh;
	unsigned int block;
	u64 ctime;
	unsigned long nsecs;
	struct inode *inode;

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

	block = clus_to_blk(sbi, ino);
	bh = sb_bread(inode->i_sb, block);
	if (!bh)
		goto iget_failed;

	oi = (struct omfs_inode *)bh->b_data;

	/* check self */
	if (ino != be64_to_cpu(oi->i_head.h_self))
		goto fail_bh;

	inode->i_uid = sbi->s_uid;
	inode->i_gid = sbi->s_gid;

	ctime = be64_to_cpu(oi->i_ctime);
	nsecs = do_div(ctime, 1000) * 1000L;

	inode->i_atime.tv_sec = ctime;
	inode->i_mtime.tv_sec = ctime;
	inode->i_ctime.tv_sec = ctime;
	inode->i_atime.tv_nsec = nsecs;
	inode->i_mtime.tv_nsec = nsecs;
	inode->i_ctime.tv_nsec = nsecs;

	inode->i_mapping->a_ops = &omfs_aops;

	switch (oi->i_type) {
	case OMFS_DIR:
		inode->i_mode = S_IFDIR | (S_IRWXUGO & ~sbi->s_dmask);
		inode->i_op = &omfs_dir_inops;
		inode->i_fop = &omfs_dir_operations;
		inode->i_size = sbi->s_sys_blocksize;
		inc_nlink(inode);
		break;
	case OMFS_FILE:
		inode->i_mode = S_IFREG | (S_IRWXUGO & ~sbi->s_fmask);
		inode->i_fop = &omfs_file_operations;
		inode->i_size = be64_to_cpu(oi->i_size);
		break;
	}
	brelse(bh);
	unlock_new_inode(inode);
	return inode;
fail_bh:
	brelse(bh);
iget_failed:
	iget_failed(inode);
	return ERR_PTR(-EIO);
}

static void omfs_put_super(struct super_block *sb)
{
	struct omfs_sb_info *sbi = OMFS_SB(sb);
	kfree(sbi->s_imap);
	kfree(sbi);
	sb->s_fs_info = NULL;
}

static int omfs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct super_block *s = dentry->d_sb;
	struct omfs_sb_info *sbi = OMFS_SB(s);
	u64 id = huge_encode_dev(s->s_bdev->bd_dev);

	buf->f_type = OMFS_MAGIC;
	buf->f_bsize = sbi->s_blocksize;
	buf->f_blocks = sbi->s_num_blocks;
	buf->f_files = sbi->s_num_blocks;
	buf->f_namelen = OMFS_NAMELEN;
	buf->f_fsid.val[0] = (u32)id;
	buf->f_fsid.val[1] = (u32)(id >> 32);

	buf->f_bfree = buf->f_bavail = buf->f_ffree =
		omfs_count_free(s);

	return 0;
}

static const struct super_operations omfs_sops = {
	.write_inode	= omfs_write_inode,
	.delete_inode	= omfs_delete_inode,
	.put_super	= omfs_put_super,
	.statfs		= omfs_statfs,
	.show_options	= generic_show_options,
};

/*
 * For Rio Karma, there is an on-disk free bitmap whose location is
 * stored in the root block.  For ReplayTV, there is no such free bitmap
 * so we have to walk the tree.  Both inodes and file data are allocated
 * from the same map.  This array can be big (300k) so we allocate
 * in units of the blocksize.
 */
static int omfs_get_imap(struct super_block *sb)
{
	int bitmap_size;
	int array_size;
	int count;
	struct omfs_sb_info *sbi = OMFS_SB(sb);
	struct buffer_head *bh;
	unsigned long **ptr;
	sector_t block;

	bitmap_size = DIV_ROUND_UP(sbi->s_num_blocks, 8);
	array_size = DIV_ROUND_UP(bitmap_size, sb->s_blocksize);

	if (sbi->s_bitmap_ino == ~0ULL)
		goto out;

	sbi->s_imap_size = array_size;
	sbi->s_imap = kzalloc(array_size * sizeof(unsigned long *), GFP_KERNEL);
	if (!sbi->s_imap)
		goto nomem;

	block = clus_to_blk(sbi, sbi->s_bitmap_ino);
	ptr = sbi->s_imap;
	for (count = bitmap_size; count > 0; count -= sb->s_blocksize) {
		bh = sb_bread(sb, block++);
		if (!bh)
			goto nomem_free;
		*ptr = kmalloc(sb->s_blocksize, GFP_KERNEL);
		if (!*ptr) {
			brelse(bh);
			goto nomem_free;
		}
		memcpy(*ptr, bh->b_data, sb->s_blocksize);
		if (count < sb->s_blocksize)
			memset((void *)*ptr + count, 0xff,
				sb->s_blocksize - count);
		brelse(bh);
		ptr++;
	}
out:
	return 0;

nomem_free:
	for (count = 0; count < array_size; count++)
		kfree(sbi->s_imap[count]);

	kfree(sbi->s_imap);
nomem:
	sbi->s_imap = NULL;
	sbi->s_imap_size = 0;
	return -ENOMEM;
}

enum {
	Opt_uid, Opt_gid, Opt_umask, Opt_dmask, Opt_fmask
};

static const match_table_t tokens = {
	{Opt_uid, "uid=%u"},
	{Opt_gid, "gid=%u"},
	{Opt_umask, "umask=%o"},
	{Opt_dmask, "dmask=%o"},
	{Opt_fmask, "fmask=%o"},
};

static int parse_options(char *options, struct omfs_sb_info *sbi)
{
	char *p;
	substring_t args[MAX_OPT_ARGS];
	int option;

	if (!options)
		return 1;

	while ((p = strsep(&options, ",")) != NULL) {
		int token;
		if (!*p)
			continue;

		token = match_token(p, tokens, args);
		switch (token) {
		case Opt_uid:
			if (match_int(&args[0], &option))
				return 0;
			sbi->s_uid = option;
			break;
		case Opt_gid:
			if (match_int(&args[0], &option))
				return 0;
			sbi->s_gid = option;
			break;
		case Opt_umask:
			if (match_octal(&args[0], &option))
				return 0;
			sbi->s_fmask = sbi->s_dmask = option;
			break;
		case Opt_dmask:
			if (match_octal(&args[0], &option))
				return 0;
			sbi->s_dmask = option;
			break;
		case Opt_fmask:
			if (match_octal(&args[0], &option))
				return 0;
			sbi->s_fmask = option;
			break;
		default:
			return 0;
		}
	}
	return 1;
}

static int omfs_fill_super(struct super_block *sb, void *data, int silent)
{
	struct buffer_head *bh, *bh2;
	struct omfs_super_block *omfs_sb;
	struct omfs_root_block *omfs_rb;
	struct omfs_sb_info *sbi;
	struct inode *root;
	sector_t start;
	int ret = -EINVAL;

	save_mount_options(sb, (char *) data);

	sbi = kzalloc(sizeof(struct omfs_sb_info), GFP_KERNEL);
	if (!sbi)
		return -ENOMEM;

	sb->s_fs_info = sbi;

	sbi->s_uid = current_uid();
	sbi->s_gid = current_gid();
	sbi->s_dmask = sbi->s_fmask = current_umask();

	if (!parse_options((char *) data, sbi))
		goto end;

	sb->s_maxbytes = 0xffffffff;

	sb_set_blocksize(sb, 0x200);

	bh = sb_bread(sb, 0);
	if (!bh)
		goto end;

	omfs_sb = (struct omfs_super_block *)bh->b_data;

	if (omfs_sb->s_magic != cpu_to_be32(OMFS_MAGIC)) {
		if (!silent)
			printk(KERN_ERR "omfs: Invalid superblock (%x)\n",
				   omfs_sb->s_magic);
		goto out_brelse_bh;
	}
	sb->s_magic = OMFS_MAGIC;

	sbi->s_num_blocks = be64_to_cpu(omfs_sb->s_num_blocks);
	sbi->s_blocksize = be32_to_cpu(omfs_sb->s_blocksize);
	sbi->s_mirrors = be32_to_cpu(omfs_sb->s_mirrors);
	sbi->s_root_ino = be64_to_cpu(omfs_sb->s_root_block);
	sbi->s_sys_blocksize = be32_to_cpu(omfs_sb->s_sys_blocksize);
	mutex_init(&sbi->s_bitmap_lock);

	if (sbi->s_sys_blocksize > PAGE_SIZE) {
		printk(KERN_ERR "omfs: sysblock size (%d) is out of range\n",
			sbi->s_sys_blocksize);
		goto out_brelse_bh;
	}

	if (sbi->s_blocksize < sbi->s_sys_blocksize ||
	    sbi->s_blocksize > OMFS_MAX_BLOCK_SIZE) {
		printk(KERN_ERR "omfs: block size (%d) is out of range\n",
			sbi->s_blocksize);
		goto out_brelse_bh;
	}

	/*
	 * Use sys_blocksize as the fs block since it is smaller than a
	 * page while the fs blocksize can be larger.
	 */
	sb_set_blocksize(sb, sbi->s_sys_blocksize);

	/*
	 * ...and the difference goes into a shift.  sys_blocksize is always
	 * a power of two factor of blocksize.
	 */
	sbi->s_block_shift = get_bitmask_order(sbi->s_blocksize) -
		get_bitmask_order(sbi->s_sys_blocksize);

	start = clus_to_blk(sbi, be64_to_cpu(omfs_sb->s_root_block));
	bh2 = sb_bread(sb, start);
	if (!bh2)
		goto out_brelse_bh;

	omfs_rb = (struct omfs_root_block *)bh2->b_data;

	sbi->s_bitmap_ino = be64_to_cpu(omfs_rb->r_bitmap);
	sbi->s_clustersize = be32_to_cpu(omfs_rb->r_clustersize);

	if (sbi->s_num_blocks != be64_to_cpu(omfs_rb->r_num_blocks)) {
		printk(KERN_ERR "omfs: block count discrepancy between "
			"super and root blocks (%llx, %llx)\n",
			(unsigned long long)sbi->s_num_blocks,
			(unsigned long long)be64_to_cpu(omfs_rb->r_num_blocks));
		goto out_brelse_bh2;
	}

	ret = omfs_get_imap(sb);
	if (ret)
		goto out_brelse_bh2;

	sb->s_op = &omfs_sops;

	root = omfs_iget(sb, be64_to_cpu(omfs_rb->r_root_dir));
	if (IS_ERR(root)) {
		ret = PTR_ERR(root);
		goto out_brelse_bh2;
	}

	sb->s_root = d_alloc_root(root);
	if (!sb->s_root) {
		iput(root);
		goto out_brelse_bh2;
	}
	printk(KERN_DEBUG "omfs: Mounted volume %s\n", omfs_rb->r_name);

	ret = 0;
out_brelse_bh2:
	brelse(bh2);
out_brelse_bh:
	brelse(bh);
end:
	return ret;
}

static int omfs_get_sb(struct file_system_type *fs_type,
			int flags, const char *dev_name,
			void *data, struct vfsmount *m)
{
	return get_sb_bdev(fs_type, flags, dev_name, data, omfs_fill_super, m);
}

static struct file_system_type omfs_fs_type = {
	.owner = THIS_MODULE,
	.name = "omfs",
	.get_sb = omfs_get_sb,
	.kill_sb = kill_block_super,
	.fs_flags = FS_REQUIRES_DEV,
};

static int __init init_omfs_fs(void)
{
	return register_filesystem(&omfs_fs_type);
}

static void __exit exit_omfs_fs(void)
{
	unregister_filesystem(&omfs_fs_type);
}

module_init(init_omfs_fs);
module_exit(exit_omfs_fs);
Commit	Line	Data
555e3775 BC	1	/*
	2	* Optimized MPEG FS - inode and super operations.
	3	* Copyright (C) 2006 Bob Copeland <me@bobcopeland.com>
	4	* Released under GPL v2.
	5	*/
555e3775 BC	6	#include <linux/module.h>
	7	#include <linux/sched.h>
	8	#include <linux/fs.h>
	9	#include <linux/vfs.h>
	10	#include <linux/parser.h>
	11	#include <linux/buffer_head.h>
	12	#include <linux/vmalloc.h>
a9185b41	13	#include <linux/writeback.h>
555e3775 BC	14	#include <linux/crc-itu-t.h>
	15	#include "omfs.h"
	16
	17	MODULE_AUTHOR("Bob Copeland <me@bobcopeland.com>");
	18	MODULE_DESCRIPTION("OMFS (ReplayTV/Karma) Filesystem for Linux");
	19	MODULE_LICENSE("GPL");
	20
	21	struct inode omfs_new_inode(struct inode dir, int mode)
	22	{
	23	struct inode *inode;
	24	u64 new_block;
	25	int err;
	26	int len;
	27	struct omfs_sb_info *sbi = OMFS_SB(dir->i_sb);
	28
	29	inode = new_inode(dir->i_sb);
	30	if (!inode)
	31	return ERR_PTR(-ENOMEM);
	32
	33	err = omfs_allocate_range(dir->i_sb, sbi->s_mirrors, sbi->s_mirrors,
	34	&new_block, &len);
	35	if (err)
	36	goto fail;
	37
	38	inode->i_ino = new_block;
	39	inode->i_mode = mode;
c222d53e DH	40	inode->i_uid = current_fsuid();
c222d53e DH	41	inode->i_gid = current_fsgid();
555e3775 BC	42	inode->i_mapping->a_ops = &omfs_aops;
	43
	44	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	45	switch (mode & S_IFMT) {
	46	case S_IFDIR:
	47	inode->i_op = &omfs_dir_inops;
	48	inode->i_fop = &omfs_dir_operations;
	49	inode->i_size = sbi->s_sys_blocksize;
	50	inc_nlink(inode);
	51	break;
	52	case S_IFREG:
	53	inode->i_op = &omfs_file_inops;
	54	inode->i_fop = &omfs_file_operations;
	55	inode->i_size = 0;
	56	break;
	57	}
	58
	59	insert_inode_hash(inode);
	60	mark_inode_dirty(inode);
	61	return inode;
	62	fail:
	63	make_bad_inode(inode);
	64	iput(inode);
	65	return ERR_PTR(err);
	66	}
	67
	68	/*
	69	* Update the header checksums for a dirty inode based on its contents.
	70	* Caller is expected to hold the buffer head underlying oi and mark it
	71	* dirty.
	72	*/
	73	static void omfs_update_checksums(struct omfs_inode *oi)
	74	{
	75	int xor, i, ofs = 0, count;
	76	u16 crc = 0;
	77	unsigned char ptr = (unsigned char ) oi;
	78
	79	count = be32_to_cpu(oi->i_head.h_body_size);
	80	ofs = sizeof(struct omfs_header);
	81
	82	crc = crc_itu_t(crc, ptr + ofs, count);
	83	oi->i_head.h_crc = cpu_to_be16(crc);
	84
	85	xor = ptr[0];
	86	for (i = 1; i < OMFS_XOR_COUNT; i++)
	87	xor ^= ptr[i];
	88
	89	oi->i_head.h_check_xor = xor;
	90	}
	91
a9185b41	92	static int __omfs_write_inode(struct inode *inode, int wait)
555e3775 BC	93	{
	94	struct omfs_inode *oi;
	95	struct omfs_sb_info *sbi = OMFS_SB(inode->i_sb);
	96	struct buffer_head bh, bh2;
	97	unsigned int block;
	98	u64 ctime;
	99	int i;
	100	int ret = -EIO;
	101	int sync_failed = 0;
	102
	103	/* get current inode since we may have written sibling ptrs etc. */
	104	block = clus_to_blk(sbi, inode->i_ino);
	105	bh = sb_bread(inode->i_sb, block);
	106	if (!bh)
	107	goto out;
	108
	109	oi = (struct omfs_inode *) bh->b_data;
	110
	111	oi->i_head.h_self = cpu_to_be64(inode->i_ino);
	112	if (S_ISDIR(inode->i_mode))
	113	oi->i_type = OMFS_DIR;
	114	else if (S_ISREG(inode->i_mode))
	115	oi->i_type = OMFS_FILE;
	116	else {
	117	printk(KERN_WARNING "omfs: unknown file type: %d\n",
	118	inode->i_mode);
	119	goto out_brelse;
	120	}
	121
	122	oi->i_head.h_body_size = cpu_to_be32(sbi->s_sys_blocksize -
	123	sizeof(struct omfs_header));
	124	oi->i_head.h_version = 1;
	125	oi->i_head.h_type = OMFS_INODE_NORMAL;
	126	oi->i_head.h_magic = OMFS_IMAGIC;
	127	oi->i_size = cpu_to_be64(inode->i_size);
	128
	129	ctime = inode->i_ctime.tv_sec * 1000LL +
	130	((inode->i_ctime.tv_nsec + 999)/1000);
	131	oi->i_ctime = cpu_to_be64(ctime);
	132
	133	omfs_update_checksums(oi);
	134
	135	mark_buffer_dirty(bh);
	136	if (wait) {
	137	sync_dirty_buffer(bh);
	138	if (buffer_req(bh) && !buffer_uptodate(bh))
	139	sync_failed = 1;
	140	}
	141
	142	/* if mirroring writes, copy to next fsblock */
	143	for (i = 1; i < sbi->s_mirrors; i++) {
	144	bh2 = sb_bread(inode->i_sb, block + i *
	145	(sbi->s_blocksize / sbi->s_sys_blocksize));
	146	if (!bh2)
	147	goto out_brelse;
	148
	149	memcpy(bh2->b_data, bh->b_data, bh->b_size);
	150	mark_buffer_dirty(bh2);
	151	if (wait) {
	152	sync_dirty_buffer(bh2);
	153	if (buffer_req(bh2) && !buffer_uptodate(bh2))
	154	sync_failed = 1;
	155	}
	156	brelse(bh2);
157	}
158	ret = (sync_failed) ? -EIO : 0;
159	out_brelse:
160	brelse(bh);
161	out:
162	return ret;
163	}
164
a9185b41 CH	165	static int omfs_write_inode(struct inode inode, struct writeback_control wbc)
	166	{
	167	return __omfs_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
	168	}
	169
555e3775 BC	170	int omfs_sync_inode(struct inode *inode)
555e3775 BC	171	{
a9185b41	172	return __omfs_write_inode(inode, 1);
555e3775 BC	173	}
	174
	175	/*
	176	* called when an entry is deleted, need to clear the bits in the
	177	* bitmaps.
	178	*/
	179	static void omfs_delete_inode(struct inode *inode)
	180	{
	181	truncate_inode_pages(&inode->i_data, 0);
	182
	183	if (S_ISREG(inode->i_mode)) {
	184	inode->i_size = 0;
	185	omfs_shrink_inode(inode);
	186	}
	187
	188	omfs_clear_range(inode->i_sb, inode->i_ino, 2);
	189	clear_inode(inode);
	190	}
	191
	192	struct inode omfs_iget(struct super_block sb, ino_t ino)
	193	{
	194	struct omfs_sb_info *sbi = OMFS_SB(sb);
	195	struct omfs_inode *oi;
	196	struct buffer_head *bh;
	197	unsigned int block;
	198	u64 ctime;
	199	unsigned long nsecs;
	200	struct inode *inode;
	201
	202	inode = iget_locked(sb, ino);
	203	if (!inode)
	204	return ERR_PTR(-ENOMEM);
	205	if (!(inode->i_state & I_NEW))
	206	return inode;
	207
	208	block = clus_to_blk(sbi, ino);
	209	bh = sb_bread(inode->i_sb, block);
	210	if (!bh)
	211	goto iget_failed;
	212
	213	oi = (struct omfs_inode *)bh->b_data;
	214
	215	/* check self */
	216	if (ino != be64_to_cpu(oi->i_head.h_self))
	217	goto fail_bh;
	218
	219	inode->i_uid = sbi->s_uid;
	220	inode->i_gid = sbi->s_gid;
	221
	222	ctime = be64_to_cpu(oi->i_ctime);
	223	nsecs = do_div(ctime, 1000) * 1000L;
	224
	225	inode->i_atime.tv_sec = ctime;
	226	inode->i_mtime.tv_sec = ctime;
	227	inode->i_ctime.tv_sec = ctime;
	228	inode->i_atime.tv_nsec = nsecs;
	229	inode->i_mtime.tv_nsec = nsecs;
	230	inode->i_ctime.tv_nsec = nsecs;
	231
	232	inode->i_mapping->a_ops = &omfs_aops;
	233
	234	switch (oi->i_type) {
	235	case OMFS_DIR:
	236	inode->i_mode = S_IFDIR \| (S_IRWXUGO & ~sbi->s_dmask);
237	inode->i_op = &omfs_dir_inops;
238	inode->i_fop = &omfs_dir_operations;
c963343a	239	inode->i_size = sbi->s_sys_blocksize;
555e3775 BC	240	inc_nlink(inode);
	241	break;
	242	case OMFS_FILE:
	243	inode->i_mode = S_IFREG \| (S_IRWXUGO & ~sbi->s_fmask);
	244	inode->i_fop = &omfs_file_operations;
	245	inode->i_size = be64_to_cpu(oi->i_size);
	246	break;
	247	}
	248	brelse(bh);
	249	unlock_new_inode(inode);
	250	return inode;
	251	fail_bh:
	252	brelse(bh);
	253	iget_failed:
	254	iget_failed(inode);
	255	return ERR_PTR(-EIO);
	256	}
	257
	258	static void omfs_put_super(struct super_block *sb)
	259	{
	260	struct omfs_sb_info *sbi = OMFS_SB(sb);
	261	kfree(sbi->s_imap);
	262	kfree(sbi);
	263	sb->s_fs_info = NULL;
	264	}
	265
	266	static int omfs_statfs(struct dentry dentry, struct kstatfs buf)
	267	{
	268	struct super_block *s = dentry->d_sb;
	269	struct omfs_sb_info *sbi = OMFS_SB(s);
197e671e CL	270	u64 id = huge_encode_dev(s->s_bdev->bd_dev);
197e671e CL	271
555e3775 BC	272	buf->f_type = OMFS_MAGIC;
	273	buf->f_bsize = sbi->s_blocksize;
	274	buf->f_blocks = sbi->s_num_blocks;
	275	buf->f_files = sbi->s_num_blocks;
	276	buf->f_namelen = OMFS_NAMELEN;
197e671e CL	277	buf->f_fsid.val[0] = (u32)id;
197e671e CL	278	buf->f_fsid.val[1] = (u32)(id >> 32);
555e3775 BC	279
	280	buf->f_bfree = buf->f_bavail = buf->f_ffree =
	281	omfs_count_free(s);
197e671e	282
555e3775 BC	283	return 0;
	284	}
	285
b87221de	286	static const struct super_operations omfs_sops = {
555e3775 BC	287	.write_inode = omfs_write_inode,
	288	.delete_inode = omfs_delete_inode,
	289	.put_super = omfs_put_super,
	290	.statfs = omfs_statfs,
	291	.show_options = generic_show_options,
	292	};
	293
	294	/*
	295	* For Rio Karma, there is an on-disk free bitmap whose location is
	296	* stored in the root block. For ReplayTV, there is no such free bitmap
	297	* so we have to walk the tree. Both inodes and file data are allocated
	298	* from the same map. This array can be big (300k) so we allocate
	299	* in units of the blocksize.
	300	*/
	301	static int omfs_get_imap(struct super_block *sb)
	302	{
	303	int bitmap_size;
	304	int array_size;
	305	int count;
	306	struct omfs_sb_info *sbi = OMFS_SB(sb);
	307	struct buffer_head *bh;
	308	unsigned long **ptr;
	309	sector_t block;
	310
	311	bitmap_size = DIV_ROUND_UP(sbi->s_num_blocks, 8);
	312	array_size = DIV_ROUND_UP(bitmap_size, sb->s_blocksize);
	313
	314	if (sbi->s_bitmap_ino == ~0ULL)
	315	goto out;
	316
	317	sbi->s_imap_size = array_size;
	318	sbi->s_imap = kzalloc(array_size * sizeof(unsigned long *), GFP_KERNEL);
	319	if (!sbi->s_imap)
	320	goto nomem;
	321
	322	block = clus_to_blk(sbi, sbi->s_bitmap_ino);
	323	ptr = sbi->s_imap;
	324	for (count = bitmap_size; count > 0; count -= sb->s_blocksize) {
	325	bh = sb_bread(sb, block++);
	326	if (!bh)
	327	goto nomem_free;
	328	*ptr = kmalloc(sb->s_blocksize, GFP_KERNEL);
	329	if (!*ptr) {
	330	brelse(bh);
	331	goto nomem_free;
	332	}
	333	memcpy(*ptr, bh->b_data, sb->s_blocksize);
	334	if (count < sb->s_blocksize)
	335	memset((void )ptr + count, 0xff,
	336	sb->s_blocksize - count);
	337	brelse(bh);
	338	ptr++;
	339	}
	340	out:
	341	return 0;
	342
	343	nomem_free:
	344	for (count = 0; count < array_size; count++)
	345	kfree(sbi->s_imap[count]);
	346
	347	kfree(sbi->s_imap);
	348	nomem:
	349	sbi->s_imap = NULL;
	350	sbi->s_imap_size = 0;
351	return -ENOMEM;
352	}
353
354	enum {
355	Opt_uid, Opt_gid, Opt_umask, Opt_dmask, Opt_fmask
356	};
357
a447c093	358	static const match_table_t tokens = {
555e3775 BC	359	{Opt_uid, "uid=%u"},
	360	{Opt_gid, "gid=%u"},
	361	{Opt_umask, "umask=%o"},
	362	{Opt_dmask, "dmask=%o"},
	363	{Opt_fmask, "fmask=%o"},
	364	};
	365
	366	static int parse_options(char options, struct omfs_sb_info sbi)
	367	{
	368	char *p;
	369	substring_t args[MAX_OPT_ARGS];
	370	int option;
	371
	372	if (!options)
	373	return 1;
	374
	375	while ((p = strsep(&options, ",")) != NULL) {
	376	int token;
	377	if (!*p)
	378	continue;
	379
	380	token = match_token(p, tokens, args);
	381	switch (token) {
	382	case Opt_uid:
	383	if (match_int(&args[0], &option))
	384	return 0;
	385	sbi->s_uid = option;
	386	break;
	387	case Opt_gid:
	388	if (match_int(&args[0], &option))
	389	return 0;
	390	sbi->s_gid = option;
	391	break;
	392	case Opt_umask:
	393	if (match_octal(&args[0], &option))
	394	return 0;
	395	sbi->s_fmask = sbi->s_dmask = option;
	396	break;
	397	case Opt_dmask:
	398	if (match_octal(&args[0], &option))
	399	return 0;
	400	sbi->s_dmask = option;
	401	break;
	402	case Opt_fmask:
	403	if (match_octal(&args[0], &option))
	404	return 0;
	405	sbi->s_fmask = option;
	406	break;
	407	default:
	408	return 0;
	409	}
	410	}
	411	return 1;
	412	}
	413
	414	static int omfs_fill_super(struct super_block sb, void data, int silent)
	415	{
	416	struct buffer_head bh, bh2;
	417	struct omfs_super_block *omfs_sb;
	418	struct omfs_root_block *omfs_rb;
	419	struct omfs_sb_info *sbi;
	420	struct inode *root;
	421	sector_t start;
	422	int ret = -EINVAL;
423
424	save_mount_options(sb, (char *) data);
425
426	sbi = kzalloc(sizeof(struct omfs_sb_info), GFP_KERNEL);
427	if (!sbi)
428	return -ENOMEM;
429
430	sb->s_fs_info = sbi;
431
c222d53e DH	432	sbi->s_uid = current_uid();
c222d53e DH	433	sbi->s_gid = current_gid();
ce3b0f8d	434	sbi->s_dmask = sbi->s_fmask = current_umask();
555e3775 BC	435
	436	if (!parse_options((char *) data, sbi))
	437	goto end;
	438
	439	sb->s_maxbytes = 0xffffffff;
	440
	441	sb_set_blocksize(sb, 0x200);
	442
	443	bh = sb_bread(sb, 0);
	444	if (!bh)
	445	goto end;
	446
	447	omfs_sb = (struct omfs_super_block *)bh->b_data;
	448
	449	if (omfs_sb->s_magic != cpu_to_be32(OMFS_MAGIC)) {
	450	if (!silent)
	451	printk(KERN_ERR "omfs: Invalid superblock (%x)\n",
	452	omfs_sb->s_magic);
	453	goto out_brelse_bh;
	454	}
	455	sb->s_magic = OMFS_MAGIC;
	456
	457	sbi->s_num_blocks = be64_to_cpu(omfs_sb->s_num_blocks);
	458	sbi->s_blocksize = be32_to_cpu(omfs_sb->s_blocksize);
	459	sbi->s_mirrors = be32_to_cpu(omfs_sb->s_mirrors);
	460	sbi->s_root_ino = be64_to_cpu(omfs_sb->s_root_block);
	461	sbi->s_sys_blocksize = be32_to_cpu(omfs_sb->s_sys_blocksize);
	462	mutex_init(&sbi->s_bitmap_lock);
	463
	464	if (sbi->s_sys_blocksize > PAGE_SIZE) {
	465	printk(KERN_ERR "omfs: sysblock size (%d) is out of range\n",
	466	sbi->s_sys_blocksize);
	467	goto out_brelse_bh;
	468	}
	469
	470	if (sbi->s_blocksize < sbi->s_sys_blocksize \|\|
	471	sbi->s_blocksize > OMFS_MAX_BLOCK_SIZE) {
	472	printk(KERN_ERR "omfs: block size (%d) is out of range\n",
	473	sbi->s_blocksize);
	474	goto out_brelse_bh;
	475	}
	476
	477	/*
	478	* Use sys_blocksize as the fs block since it is smaller than a
	479	* page while the fs blocksize can be larger.
	480	*/
	481	sb_set_blocksize(sb, sbi->s_sys_blocksize);
	482
	483	/*
	484	* ...and the difference goes into a shift. sys_blocksize is always
	485	* a power of two factor of blocksize.
	486	*/
	487	sbi->s_block_shift = get_bitmask_order(sbi->s_blocksize) -
	488	get_bitmask_order(sbi->s_sys_blocksize);
	489
	490	start = clus_to_blk(sbi, be64_to_cpu(omfs_sb->s_root_block));
	491	bh2 = sb_bread(sb, start);
	492	if (!bh2)
	493	goto out_brelse_bh;
	494
	495	omfs_rb = (struct omfs_root_block *)bh2->b_data;
	496
	497	sbi->s_bitmap_ino = be64_to_cpu(omfs_rb->r_bitmap);
	498	sbi->s_clustersize = be32_to_cpu(omfs_rb->r_clustersize);
499
500	if (sbi->s_num_blocks != be64_to_cpu(omfs_rb->r_num_blocks)) {
501	printk(KERN_ERR "omfs: block count discrepancy between "
502	"super and root blocks (%llx, %llx)\n",
dc60bf1d AB	503	(unsigned long long)sbi->s_num_blocks,
dc60bf1d AB	504	(unsigned long long)be64_to_cpu(omfs_rb->r_num_blocks));
555e3775 BC	505	goto out_brelse_bh2;
	506	}
	507
	508	ret = omfs_get_imap(sb);
	509	if (ret)
	510	goto out_brelse_bh2;
	511
	512	sb->s_op = &omfs_sops;
	513
	514	root = omfs_iget(sb, be64_to_cpu(omfs_rb->r_root_dir));
	515	if (IS_ERR(root)) {
	516	ret = PTR_ERR(root);
	517	goto out_brelse_bh2;
	518	}
	519
	520	sb->s_root = d_alloc_root(root);
	521	if (!sb->s_root) {
	522	iput(root);
	523	goto out_brelse_bh2;
	524	}
	525	printk(KERN_DEBUG "omfs: Mounted volume %s\n", omfs_rb->r_name);
	526
	527	ret = 0;
	528	out_brelse_bh2:
	529	brelse(bh2);
	530	out_brelse_bh:
	531	brelse(bh);
	532	end:
	533	return ret;
	534	}
	535
	536	static int omfs_get_sb(struct file_system_type *fs_type,
	537	int flags, const char *dev_name,
	538	void data, struct vfsmount m)
	539	{
	540	return get_sb_bdev(fs_type, flags, dev_name, data, omfs_fill_super, m);
	541	}
	542
	543	static struct file_system_type omfs_fs_type = {
	544	.owner = THIS_MODULE,
	545	.name = "omfs",
	546	.get_sb = omfs_get_sb,
	547	.kill_sb = kill_block_super,
	548	.fs_flags = FS_REQUIRES_DEV,
	549	};
	550
	551	static int __init init_omfs_fs(void)
	552	{
	553	return register_filesystem(&omfs_fs_type);
	554	}
	555
	556	static void __exit exit_omfs_fs(void)
	557	{
	558	unregister_filesystem(&omfs_fs_type);
	559	}
	560
	561	module_init(init_omfs_fs);
	562	module_exit(exit_omfs_fs);