super.c

UnixBSD、SunOs、FreeBSD、NetBSD、OpenBSD和NeXTStep文件系统源代码

	uspi->s_cblkno = fs32_to_cpu(sb, usb1->fs_cblkno);
	uspi->s_iblkno = fs32_to_cpu(sb, usb1->fs_iblkno);
	uspi->s_dblkno = fs32_to_cpu(sb, usb1->fs_dblkno);
	uspi->s_cgoffset = fs32_to_cpu(sb, usb1->fs_cgoffset);
	uspi->s_cgmask = fs32_to_cpu(sb, usb1->fs_cgmask);

	if ((flags & UFS_TYPE_MASK) == UFS_TYPE_UFS2) {
		uspi->s_u2_size  = fs64_to_cpu(sb, usb3->fs_un1.fs_u2.fs_size);
		uspi->s_u2_dsize = fs64_to_cpu(sb, usb3->fs_un1.fs_u2.fs_dsize);
	} else {
		uspi->s_size  =  fs32_to_cpu(sb, usb1->fs_size);
		uspi->s_dsize =  fs32_to_cpu(sb, usb1->fs_dsize);
	}

	uspi->s_ncg = fs32_to_cpu(sb, usb1->fs_ncg);
	/* s_bsize already set */
	/* s_fsize already set */
	uspi->s_fpb = fs32_to_cpu(sb, usb1->fs_frag);
	uspi->s_minfree = fs32_to_cpu(sb, usb1->fs_minfree);
	uspi->s_bmask = fs32_to_cpu(sb, usb1->fs_bmask);
	uspi->s_fmask = fs32_to_cpu(sb, usb1->fs_fmask);
	uspi->s_bshift = fs32_to_cpu(sb, usb1->fs_bshift);
	uspi->s_fshift = fs32_to_cpu(sb, usb1->fs_fshift);
	UFSD("uspi->s_bshift = %d,uspi->s_fshift = %d", uspi->s_bshift,
		uspi->s_fshift);
	uspi->s_fpbshift = fs32_to_cpu(sb, usb1->fs_fragshift);
	uspi->s_fsbtodb = fs32_to_cpu(sb, usb1->fs_fsbtodb);
	/* s_sbsize already set */
	uspi->s_csmask = fs32_to_cpu(sb, usb1->fs_csmask);
	uspi->s_csshift = fs32_to_cpu(sb, usb1->fs_csshift);
	uspi->s_nindir = fs32_to_cpu(sb, usb1->fs_nindir);
	uspi->s_inopb = fs32_to_cpu(sb, usb1->fs_inopb);
	uspi->s_nspf = fs32_to_cpu(sb, usb1->fs_nspf);
	uspi->s_npsect = ufs_get_fs_npsect(sb, usb1, usb3);
	uspi->s_interleave = fs32_to_cpu(sb, usb1->fs_interleave);
	uspi->s_trackskew = fs32_to_cpu(sb, usb1->fs_trackskew);

	if (uspi->fs_magic == UFS2_MAGIC)
		uspi->s_csaddr = fs64_to_cpu(sb, usb3->fs_un1.fs_u2.fs_csaddr);
	else
		uspi->s_csaddr = fs32_to_cpu(sb, usb1->fs_csaddr);

	uspi->s_cssize = fs32_to_cpu(sb, usb1->fs_cssize);
	uspi->s_cgsize = fs32_to_cpu(sb, usb1->fs_cgsize);
	uspi->s_ntrak = fs32_to_cpu(sb, usb1->fs_ntrak);
	uspi->s_nsect = fs32_to_cpu(sb, usb1->fs_nsect);
	uspi->s_spc = fs32_to_cpu(sb, usb1->fs_spc);
	uspi->s_ipg = fs32_to_cpu(sb, usb1->fs_ipg);
	uspi->s_fpg = fs32_to_cpu(sb, usb1->fs_fpg);
	uspi->s_cpc = fs32_to_cpu(sb, usb2->fs_un.fs_u1.fs_cpc);
	uspi->s_contigsumsize = fs32_to_cpu(sb, usb3->fs_un2.fs_44.fs_contigsumsize);
	uspi->s_qbmask = ufs_get_fs_qbmask(sb, usb3);
	uspi->s_qfmask = ufs_get_fs_qfmask(sb, usb3);
	uspi->s_nrpos = fs32_to_cpu(sb, usb3->fs_nrpos);
	uspi->s_postbloff = fs32_to_cpu(sb, usb3->fs_postbloff);
	uspi->s_rotbloff = fs32_to_cpu(sb, usb3->fs_rotbloff);

	/*
	 * Compute another frequently used values
	 */
	uspi->s_fpbmask = uspi->s_fpb - 1;
	if ((flags & UFS_TYPE_MASK) == UFS_TYPE_UFS2)
		uspi->s_apbshift = uspi->s_bshift - 3;
	else
		uspi->s_apbshift = uspi->s_bshift - 2;

	uspi->s_2apbshift = uspi->s_apbshift * 2;
	uspi->s_3apbshift = uspi->s_apbshift * 3;
	uspi->s_apb = 1 << uspi->s_apbshift;
	uspi->s_2apb = 1 << uspi->s_2apbshift;
	uspi->s_3apb = 1 << uspi->s_3apbshift;
	uspi->s_apbmask = uspi->s_apb - 1;
	uspi->s_nspfshift = uspi->s_fshift - UFS_SECTOR_BITS;
	uspi->s_nspb = uspi->s_nspf << uspi->s_fpbshift;
	uspi->s_inopf = uspi->s_inopb >> uspi->s_fpbshift;
	uspi->s_bpf = uspi->s_fsize << 3;
	uspi->s_bpfshift = uspi->s_fshift + 3;
	uspi->s_bpfmask = uspi->s_bpf - 1;
	if ((sbi->s_mount_opt & UFS_MOUNT_UFSTYPE) == UFS_MOUNT_UFSTYPE_44BSD ||
	    (sbi->s_mount_opt & UFS_MOUNT_UFSTYPE) == UFS_MOUNT_UFSTYPE_UFS2)
		uspi->s_maxsymlinklen =
		    fs32_to_cpu(sb, usb3->fs_un2.fs_44.fs_maxsymlinklen);

	inode = ufs_iget(sb, UFS_ROOTINO);
	if (IS_ERR(inode)) {
		ret = PTR_ERR(inode);
		goto failed;
	}
	sb->s_root = d_alloc_root(inode);
	if (!sb->s_root) {
		ret = -ENOMEM;
		goto dalloc_failed;
	}

	ufs_setup_cstotal(sb);
	/*
	 * Read cylinder group structures
	 */
	if (!(sb->s_flags & MS_RDONLY))
		if (!ufs_read_cylinder_structures(sb))
			goto failed;

	UFSD("EXIT\n");
	return 0;

dalloc_failed:
	iput(inode);
failed:
	if (ubh)
		ubh_brelse_uspi (uspi);
	kfree (uspi);
	kfree(sbi);
	sb->s_fs_info = NULL;
	UFSD("EXIT (FAILED)\n");
	return ret;

failed_nomem:
	UFSD("EXIT (NOMEM)\n");
	return -ENOMEM;
}

static void ufs_write_super(struct super_block *sb)
{
	struct ufs_sb_private_info * uspi;
	struct ufs_super_block_first * usb1;
	struct ufs_super_block_third * usb3;
	unsigned flags;

	lock_kernel();
	UFSD("ENTER\n");
	flags = UFS_SB(sb)->s_flags;
	uspi = UFS_SB(sb)->s_uspi;
	usb1 = ubh_get_usb_first(uspi);
	usb3 = ubh_get_usb_third(uspi);

	if (!(sb->s_flags & MS_RDONLY)) {
		usb1->fs_time = cpu_to_fs32(sb, get_seconds());
		if ((flags & UFS_ST_MASK) == UFS_ST_SUN 
		  || (flags & UFS_ST_MASK) == UFS_ST_SUNOS
		  || (flags & UFS_ST_MASK) == UFS_ST_SUNx86)
			ufs_set_fs_state(sb, usb1, usb3,
					UFS_FSOK - fs32_to_cpu(sb, usb1->fs_time));
		ufs_put_cstotal(sb);
	}
	sb->s_dirt = 0;
	UFSD("EXIT\n");
	unlock_kernel();
}

static void ufs_put_super(struct super_block *sb)
{
	struct ufs_sb_info * sbi = UFS_SB(sb);
		
	UFSD("ENTER\n");

	if (!(sb->s_flags & MS_RDONLY))
		ufs_put_super_internal(sb);
	
	ubh_brelse_uspi (sbi->s_uspi);
	kfree (sbi->s_uspi);
	kfree (sbi);
	sb->s_fs_info = NULL;
	UFSD("EXIT\n");
	return;
}


static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
{
	struct ufs_sb_private_info * uspi;
	struct ufs_super_block_first * usb1;
	struct ufs_super_block_third * usb3;
	unsigned new_mount_opt, ufstype;
	unsigned flags;
	
	uspi = UFS_SB(sb)->s_uspi;
	flags = UFS_SB(sb)->s_flags;
	usb1 = ubh_get_usb_first(uspi);
	usb3 = ubh_get_usb_third(uspi);
	
	/*
	 * Allow the "check" option to be passed as a remount option.
	 * It is not possible to change ufstype option during remount
	 */
	ufstype = UFS_SB(sb)->s_mount_opt & UFS_MOUNT_UFSTYPE;
	new_mount_opt = 0;
	ufs_set_opt (new_mount_opt, ONERROR_LOCK);
	if (!ufs_parse_options (data, &new_mount_opt))
		return -EINVAL;
	if (!(new_mount_opt & UFS_MOUNT_UFSTYPE)) {
		new_mount_opt |= ufstype;
	} else if ((new_mount_opt & UFS_MOUNT_UFSTYPE) != ufstype) {
		printk("ufstype can't be changed during remount\n");
		return -EINVAL;
	}

	if ((*mount_flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
		UFS_SB(sb)->s_mount_opt = new_mount_opt;
		return 0;
	}
	
	/*
	 * fs was mouted as rw, remounting ro
	 */
	if (*mount_flags & MS_RDONLY) {
		ufs_put_super_internal(sb);
		usb1->fs_time = cpu_to_fs32(sb, get_seconds());
		if ((flags & UFS_ST_MASK) == UFS_ST_SUN
		  || (flags & UFS_ST_MASK) == UFS_ST_SUNOS
		  || (flags & UFS_ST_MASK) == UFS_ST_SUNx86) 
			ufs_set_fs_state(sb, usb1, usb3,
				UFS_FSOK - fs32_to_cpu(sb, usb1->fs_time));
		ubh_mark_buffer_dirty (USPI_UBH(uspi));
		sb->s_dirt = 0;
		sb->s_flags |= MS_RDONLY;
	} else {
	/*
	 * fs was mounted as ro, remounting rw
	 */
#ifndef CONFIG_UFS_FS_WRITE
		printk("ufs was compiled with read-only support, "
		"can't be mounted as read-write\n");
		return -EINVAL;
#else
		if (ufstype != UFS_MOUNT_UFSTYPE_SUN && 
		    ufstype != UFS_MOUNT_UFSTYPE_SUNOS &&
		    ufstype != UFS_MOUNT_UFSTYPE_44BSD &&
		    ufstype != UFS_MOUNT_UFSTYPE_SUNx86 &&
		    ufstype != UFS_MOUNT_UFSTYPE_UFS2) {
			printk("this ufstype is read-only supported\n");
			return -EINVAL;
		}
		if (!ufs_read_cylinder_structures(sb)) {
			printk("failed during remounting\n");
			return -EPERM;
		}
		sb->s_flags &= ~MS_RDONLY;
#endif
	}
	UFS_SB(sb)->s_mount_opt = new_mount_opt;
	return 0;
}

static int ufs_show_options(struct seq_file *seq, struct vfsmount *vfs)
{
	struct ufs_sb_info *sbi = UFS_SB(vfs->mnt_sb);
	unsigned mval = sbi->s_mount_opt & UFS_MOUNT_UFSTYPE;
	const struct match_token *tp = tokens;

	while (tp->token != Opt_onerror_panic && tp->token != mval)
		++tp;
	BUG_ON(tp->token == Opt_onerror_panic);
	seq_printf(seq, ",%s", tp->pattern);

	mval = sbi->s_mount_opt & UFS_MOUNT_ONERROR;
	while (tp->token != Opt_err && tp->token != mval)
		++tp;
	BUG_ON(tp->token == Opt_err);
	seq_printf(seq, ",%s", tp->pattern);

	return 0;
}

static int ufs_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct super_block *sb = dentry->d_sb;
	struct ufs_sb_private_info *uspi= UFS_SB(sb)->s_uspi;
	unsigned  flags = UFS_SB(sb)->s_flags;
	struct ufs_super_block_first *usb1;
	struct ufs_super_block_second *usb2;
	struct ufs_super_block_third *usb3;

	lock_kernel();

	usb1 = ubh_get_usb_first(uspi);
	usb2 = ubh_get_usb_second(uspi);
	usb3 = ubh_get_usb_third(uspi);
	
	if ((flags & UFS_TYPE_MASK) == UFS_TYPE_UFS2) {
		buf->f_type = UFS2_MAGIC;
		buf->f_blocks = fs64_to_cpu(sb, usb3->fs_un1.fs_u2.fs_dsize);
	} else {
		buf->f_type = UFS_MAGIC;
		buf->f_blocks = uspi->s_dsize;
	}
	buf->f_bfree = ufs_blkstofrags(uspi->cs_total.cs_nbfree) +
		uspi->cs_total.cs_nffree;
	buf->f_ffree = uspi->cs_total.cs_nifree;
	buf->f_bsize = sb->s_blocksize;
	buf->f_bavail = (buf->f_bfree > (((long)buf->f_blocks / 100) * uspi->s_minfree))
		? (buf->f_bfree - (((long)buf->f_blocks / 100) * uspi->s_minfree)) : 0;
	buf->f_files = uspi->s_ncg * uspi->s_ipg;
	buf->f_namelen = UFS_MAXNAMLEN;

	unlock_kernel();

	return 0;
}

static struct kmem_cache * ufs_inode_cachep;

static struct inode *ufs_alloc_inode(struct super_block *sb)
{
	struct ufs_inode_info *ei;
	ei = (struct ufs_inode_info *)kmem_cache_alloc(ufs_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	ei->vfs_inode.i_version = 1;
	return &ei->vfs_inode;
}

static void ufs_destroy_inode(struct inode *inode)
{
	kmem_cache_free(ufs_inode_cachep, UFS_I(inode));
}

static void init_once(void *foo)
{
	struct ufs_inode_info *ei = (struct ufs_inode_info *) foo;

	inode_init_once(&ei->vfs_inode);
}

static int init_inodecache(void)
{
	ufs_inode_cachep = kmem_cache_create("ufs_inode_cache",
					     sizeof(struct ufs_inode_info),
					     0, (SLAB_RECLAIM_ACCOUNT|
						SLAB_MEM_SPREAD),
					     init_once);
	if (ufs_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

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

#ifdef CONFIG_QUOTA
static ssize_t ufs_quota_read(struct super_block *, int, char *,size_t, loff_t);
static ssize_t ufs_quota_write(struct super_block *, int, const char *, size_t, loff_t);
#endif

static const struct super_operations ufs_super_ops = {
	.alloc_inode	= ufs_alloc_inode,
	.destroy_inode	= ufs_destroy_inode,
	.write_inode	= ufs_write_inode,
	.delete_inode	= ufs_delete_inode,
	.put_super	= ufs_put_super,
	.write_super	= ufs_write_super,
	.statfs		= ufs_statfs,
	.remount_fs	= ufs_remount,
	.show_options   = ufs_show_options,
#ifdef CONFIG_QUOTA
	.quota_read	= ufs_quota_read,
	.quota_write	= ufs_quota_write,
#endif
};

#ifdef CONFIG_QUOTA

/* Read data from quotafile - avoid pagecache and such because we cannot afford
 * acquiring the locks... As quota files are never truncated and quota code
 * itself serializes the operations (and noone else should touch the files)
 * we don't have to be afraid of races */
static ssize_t ufs_quota_read(struct super_block *sb, int type, char *data,
			       size_t len, loff_t off)
{
	struct inode *inode = sb_dqopt(sb)->files[type];
	sector_t blk = off >> sb->s_blocksize_bits;
	int err = 0;
	int offset = off & (sb->s_blocksize - 1);
	int tocopy;
	size_t toread;
	struct buffer_head *bh;
	loff_t i_size = i_size_read(inode);

	if (off > i_size)
		return 0;
	if (off+len > i_size)
		len = i_size-off;
	toread = len;
	while (toread > 0) {
		tocopy = sb->s_blocksize - offset < toread ?
				sb->s_blocksize - offset : toread;

		bh = ufs_bread(inode, blk, 0, &err);
		if (err)
			return err;
		if (!bh)	/* A hole? */
			memset(data, 0, tocopy);
		else {
			memcpy(data, bh->b_data+offset, tocopy);
			brelse(bh);
		}
		offset = 0;
		toread -= tocopy;
		data += tocopy;
		blk++;
	}
	return len;
}

/* Write to quotafile */
static ssize_t ufs_quota_write(struct super_block *sb, int type,
				const char *data, size_t len, loff_t off)
{
	struct inode *inode = sb_dqopt(sb)->files[type];
	sector_t blk = off >> sb->s_blocksize_bits;
	int err = 0;
	int offset = off & (sb->s_blocksize - 1);
	int tocopy;
	size_t towrite = len;
	struct buffer_head *bh;

	mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
	while (towrite > 0) {
		tocopy = sb->s_blocksize - offset < towrite ?
				sb->s_blocksize - offset : towrite;

		bh = ufs_bread(inode, blk, 1, &err);
		if (!bh)
			goto out;
		lock_buffer(bh);
		memcpy(bh->b_data+offset, data, tocopy);
		flush_dcache_page(bh->b_page);
		set_buffer_uptodate(bh);
		mark_buffer_dirty(bh);
		unlock_buffer(bh);
		brelse(bh);
		offset = 0;
		towrite -= tocopy;
		data += tocopy;
		blk++;
	}
out:
	if (len == towrite) {
		mutex_unlock(&inode->i_mutex);
		return err;
	}
	if (inode->i_size < off+len-towrite)
		i_size_write(inode, off+len-towrite);
	inode->i_version++;
	inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
	mark_inode_dirty(inode);
	mutex_unlock(&inode->i_mutex);
	return len - towrite;
}

#endif

static int ufs_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, ufs_fill_super, mnt);
}

static struct file_system_type ufs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "ufs",
	.get_sb		= ufs_get_sb,
	.kill_sb	= kill_block_super,
	.fs_flags	= FS_REQUIRES_DEV,
};

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

static void __exit exit_ufs_fs(void)
{
	unregister_filesystem(&ufs_fs_type);
	destroy_inodecache();
}

module_init(init_ufs_fs)
module_exit(exit_ufs_fs)
MODULE_LICENSE("GPL");