/*
   *  linux/fs/hfsplus/super.c
   *
   * Copyright (C) 2001
   * Brad Boyer (flar@allandria.com)
   * (C) 2003 Ardis Technologies <roman@ardistech.com>
   *
   */

  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/pagemap.h>
  #include <linux/fs.h>

  #include <linux/slab.h>

  #include <linux/vfs.h>
  #include <linux/nls.h>
  
  static struct inode *hfsplus_alloc_inode(struct super_block *sb);
  static void hfsplus_destroy_inode(struct inode *inode);
  
  #include "hfsplus_fs.h"

  struct inode *hfsplus_iget(struct super_block *sb, unsigned long ino)

  {
  	struct hfs_find_data fd;
  	struct hfsplus_vh *vhdr;

  	struct inode *inode;
  	long err = -EIO;
  
  	inode = iget_locked(sb, ino);
  	if (!inode)
  		return ERR_PTR(-ENOMEM);
  	if (!(inode->i_state & I_NEW))
  		return inode;

  	INIT_LIST_HEAD(&HFSPLUS_I(inode).open_dir_list);

  	mutex_init(&HFSPLUS_I(inode).extents_lock);

  	HFSPLUS_I(inode).flags = 0;
  	HFSPLUS_I(inode).rsrc_inode = NULL;

  	atomic_set(&HFSPLUS_I(inode).opencnt, 0);

  
  	if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID) {
  	read_inode:
  		hfs_find_init(HFSPLUS_SB(inode->i_sb).cat_tree, &fd);
  		err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
  		if (!err)
  			err = hfsplus_cat_read_inode(inode, &fd);
  		hfs_find_exit(&fd);
  		if (err)
  			goto bad_inode;

  		goto done;

  	}
  	vhdr = HFSPLUS_SB(inode->i_sb).s_vhdr;
  	switch(inode->i_ino) {
  	case HFSPLUS_ROOT_CNID:
  		goto read_inode;
  	case HFSPLUS_EXT_CNID:
  		hfsplus_inode_read_fork(inode, &vhdr->ext_file);
  		inode->i_mapping->a_ops = &hfsplus_btree_aops;
  		break;
  	case HFSPLUS_CAT_CNID:
  		hfsplus_inode_read_fork(inode, &vhdr->cat_file);
  		inode->i_mapping->a_ops = &hfsplus_btree_aops;
  		break;
  	case HFSPLUS_ALLOC_CNID:
  		hfsplus_inode_read_fork(inode, &vhdr->alloc_file);
  		inode->i_mapping->a_ops = &hfsplus_aops;
  		break;
  	case HFSPLUS_START_CNID:
  		hfsplus_inode_read_fork(inode, &vhdr->start_file);
  		break;
  	case HFSPLUS_ATTR_CNID:
  		hfsplus_inode_read_fork(inode, &vhdr->attr_file);
  		inode->i_mapping->a_ops = &hfsplus_btree_aops;
  		break;
  	default:
  		goto bad_inode;
  	}

  done:
  	unlock_new_inode(inode);
  	return inode;

  bad_inode:
  	iget_failed(inode);
  	return ERR_PTR(err);

  }
  
  static int hfsplus_write_inode(struct inode *inode, int unused)
  {
  	struct hfsplus_vh *vhdr;
  	int ret = 0;
  
  	dprint(DBG_INODE, "hfsplus_write_inode: %lu
  ", inode->i_ino);
  	hfsplus_ext_write_extent(inode);
  	if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID) {
  		return hfsplus_cat_write_inode(inode);
  	}
  	vhdr = HFSPLUS_SB(inode->i_sb).s_vhdr;
  	switch (inode->i_ino) {
  	case HFSPLUS_ROOT_CNID:
  		ret = hfsplus_cat_write_inode(inode);
  		break;
  	case HFSPLUS_EXT_CNID:
  		if (vhdr->ext_file.total_size != cpu_to_be64(inode->i_size)) {
  			HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
  			inode->i_sb->s_dirt = 1;
  		}
  		hfsplus_inode_write_fork(inode, &vhdr->ext_file);
  		hfs_btree_write(HFSPLUS_SB(inode->i_sb).ext_tree);
  		break;
  	case HFSPLUS_CAT_CNID:
  		if (vhdr->cat_file.total_size != cpu_to_be64(inode->i_size)) {
  			HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
  			inode->i_sb->s_dirt = 1;
  		}
  		hfsplus_inode_write_fork(inode, &vhdr->cat_file);
  		hfs_btree_write(HFSPLUS_SB(inode->i_sb).cat_tree);
  		break;
  	case HFSPLUS_ALLOC_CNID:
  		if (vhdr->alloc_file.total_size != cpu_to_be64(inode->i_size)) {
  			HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
  			inode->i_sb->s_dirt = 1;
  		}
  		hfsplus_inode_write_fork(inode, &vhdr->alloc_file);
  		break;
  	case HFSPLUS_START_CNID:
  		if (vhdr->start_file.total_size != cpu_to_be64(inode->i_size)) {
  			HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
  			inode->i_sb->s_dirt = 1;
  		}
  		hfsplus_inode_write_fork(inode, &vhdr->start_file);
  		break;
  	case HFSPLUS_ATTR_CNID:
  		if (vhdr->attr_file.total_size != cpu_to_be64(inode->i_size)) {
  			HFSPLUS_SB(inode->i_sb).flags |= HFSPLUS_SB_WRITEBACKUP;
  			inode->i_sb->s_dirt = 1;
  		}
  		hfsplus_inode_write_fork(inode, &vhdr->attr_file);
  		hfs_btree_write(HFSPLUS_SB(inode->i_sb).attr_tree);
  		break;
  	}
  	return ret;
  }
  
  static void hfsplus_clear_inode(struct inode *inode)
  {
  	dprint(DBG_INODE, "hfsplus_clear_inode: %lu
  ", inode->i_ino);

  	if (HFSPLUS_IS_RSRC(inode)) {
  		HFSPLUS_I(HFSPLUS_I(inode).rsrc_inode).rsrc_inode = NULL;
  		iput(HFSPLUS_I(inode).rsrc_inode);
  	}

  }
  
  static void hfsplus_write_super(struct super_block *sb)
  {
  	struct hfsplus_vh *vhdr = HFSPLUS_SB(sb).s_vhdr;
  
  	dprint(DBG_SUPER, "hfsplus_write_super
  ");
  	sb->s_dirt = 0;
  	if (sb->s_flags & MS_RDONLY)
  		/* warn? */
  		return;
  
  	vhdr->free_blocks = cpu_to_be32(HFSPLUS_SB(sb).free_blocks);
  	vhdr->next_alloc = cpu_to_be32(HFSPLUS_SB(sb).next_alloc);
  	vhdr->next_cnid = cpu_to_be32(HFSPLUS_SB(sb).next_cnid);
  	vhdr->folder_count = cpu_to_be32(HFSPLUS_SB(sb).folder_count);
  	vhdr->file_count = cpu_to_be32(HFSPLUS_SB(sb).file_count);
  
  	mark_buffer_dirty(HFSPLUS_SB(sb).s_vhbh);
  	if (HFSPLUS_SB(sb).flags & HFSPLUS_SB_WRITEBACKUP) {
  		if (HFSPLUS_SB(sb).sect_count) {
  			struct buffer_head *bh;
  			u32 block, offset;
  
  			block = HFSPLUS_SB(sb).blockoffset;
  			block += (HFSPLUS_SB(sb).sect_count - 2) >> (sb->s_blocksize_bits - 9);
  			offset = ((HFSPLUS_SB(sb).sect_count - 2) << 9) & (sb->s_blocksize - 1);

  			printk(KERN_DEBUG "hfs: backup: %u,%u,%u,%u
  ", HFSPLUS_SB(sb).blockoffset,

  				HFSPLUS_SB(sb).sect_count, block, offset);
  			bh = sb_bread(sb, block);
  			if (bh) {
  				vhdr = (struct hfsplus_vh *)(bh->b_data + offset);
  				if (be16_to_cpu(vhdr->signature) == HFSPLUS_VOLHEAD_SIG) {
  					memcpy(vhdr, HFSPLUS_SB(sb).s_vhdr, sizeof(*vhdr));
  					mark_buffer_dirty(bh);
  					brelse(bh);
  				} else

  					printk(KERN_WARNING "hfs: backup not found!
  ");

  			}
  		}
  		HFSPLUS_SB(sb).flags &= ~HFSPLUS_SB_WRITEBACKUP;
  	}
  }
  
  static void hfsplus_put_super(struct super_block *sb)
  {
  	dprint(DBG_SUPER, "hfsplus_put_super
  ");

  	if (!sb->s_fs_info)
  		return;
  	if (!(sb->s_flags & MS_RDONLY) && HFSPLUS_SB(sb).s_vhdr) {

  		struct hfsplus_vh *vhdr = HFSPLUS_SB(sb).s_vhdr;
  
  		vhdr->modify_date = hfsp_now2mt();
  		vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
  		vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);
  		mark_buffer_dirty(HFSPLUS_SB(sb).s_vhbh);

  		sync_dirty_buffer(HFSPLUS_SB(sb).s_vhbh);

  	}
  
  	hfs_btree_close(HFSPLUS_SB(sb).cat_tree);
  	hfs_btree_close(HFSPLUS_SB(sb).ext_tree);
  	iput(HFSPLUS_SB(sb).alloc_file);
  	iput(HFSPLUS_SB(sb).hidden_dir);
  	brelse(HFSPLUS_SB(sb).s_vhbh);
  	if (HFSPLUS_SB(sb).nls)
  		unload_nls(HFSPLUS_SB(sb).nls);

  	kfree(sb->s_fs_info);
  	sb->s_fs_info = NULL;

  }

  static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)

  {

  	struct super_block *sb = dentry->d_sb;

  	buf->f_type = HFSPLUS_SUPER_MAGIC;
  	buf->f_bsize = sb->s_blocksize;
  	buf->f_blocks = HFSPLUS_SB(sb).total_blocks << HFSPLUS_SB(sb).fs_shift;
  	buf->f_bfree = HFSPLUS_SB(sb).free_blocks << HFSPLUS_SB(sb).fs_shift;
  	buf->f_bavail = buf->f_bfree;
  	buf->f_files = 0xFFFFFFFF;
  	buf->f_ffree = 0xFFFFFFFF - HFSPLUS_SB(sb).next_cnid;
  	buf->f_namelen = HFSPLUS_MAX_STRLEN;
  
  	return 0;
  }
  
  static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
  {
  	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
  		return 0;
  	if (!(*flags & MS_RDONLY)) {
  		struct hfsplus_vh *vhdr = HFSPLUS_SB(sb).s_vhdr;

  		struct hfsplus_sb_info sbi;
  
  		memset(&sbi, 0, sizeof(struct hfsplus_sb_info));
  		sbi.nls = HFSPLUS_SB(sb).nls;
  		if (!hfsplus_parse_options(data, &sbi))
  			return -EINVAL;

  
  		if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {

  			printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, "

  			       "running fsck.hfsplus is recommended.  leaving read-only.
  ");
  			sb->s_flags |= MS_RDONLY;
  			*flags |= MS_RDONLY;

  		} else if (sbi.flags & HFSPLUS_SB_FORCE) {
  			/* nothing */

  		} else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {

  			printk(KERN_WARNING "hfs: filesystem is marked locked, leaving read-only.
  ");

  			sb->s_flags |= MS_RDONLY;
  			*flags |= MS_RDONLY;

  		} else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {

  			printk(KERN_WARNING "hfs: filesystem is marked journaled, leaving read-only.
  ");

  			sb->s_flags |= MS_RDONLY;
  			*flags |= MS_RDONLY;

  		}
  	}
  	return 0;
  }

  static const struct super_operations hfsplus_sops = {

  	.alloc_inode	= hfsplus_alloc_inode,
  	.destroy_inode	= hfsplus_destroy_inode,

  	.write_inode	= hfsplus_write_inode,
  	.clear_inode	= hfsplus_clear_inode,
  	.put_super	= hfsplus_put_super,
  	.write_super	= hfsplus_write_super,
  	.statfs		= hfsplus_statfs,
  	.remount_fs	= hfsplus_remount,

  	.show_options	= hfsplus_show_options,

  };
  
  static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
  {
  	struct hfsplus_vh *vhdr;
  	struct hfsplus_sb_info *sbi;
  	hfsplus_cat_entry entry;
  	struct hfs_find_data fd;

  	struct inode *root, *inode;

  	struct qstr str;
  	struct nls_table *nls = NULL;
  	int err = -EINVAL;

  	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);

  	if (!sbi)
  		return -ENOMEM;

  	sb->s_fs_info = sbi;
  	INIT_HLIST_HEAD(&sbi->rsrc_inodes);

  	hfsplus_fill_defaults(sbi);
  	if (!hfsplus_parse_options(data, sbi)) {

  		printk(KERN_ERR "hfs: unable to parse mount options
  ");

  		err = -EINVAL;
  		goto cleanup;
  	}
  
  	/* temporarily use utf8 to correctly find the hidden dir below */
  	nls = sbi->nls;
  	sbi->nls = load_nls("utf8");

  	if (!sbi->nls) {

  		printk(KERN_ERR "hfs: unable to load nls for utf8
  ");

  		err = -EINVAL;
  		goto cleanup;
  	}
  
  	/* Grab the volume header */
  	if (hfsplus_read_wrapper(sb)) {
  		if (!silent)

  			printk(KERN_WARNING "hfs: unable to find HFS+ superblock
  ");

  		err = -EINVAL;
  		goto cleanup;
  	}
  	vhdr = HFSPLUS_SB(sb).s_vhdr;
  
  	/* Copy parts of the volume header into the superblock */

  	sb->s_magic = HFSPLUS_VOLHEAD_SIG;
  	if (be16_to_cpu(vhdr->version) < HFSPLUS_MIN_VERSION ||
  	    be16_to_cpu(vhdr->version) > HFSPLUS_CURRENT_VERSION) {

  		printk(KERN_ERR "hfs: wrong filesystem version
  ");

  		goto cleanup;
  	}
  	HFSPLUS_SB(sb).total_blocks = be32_to_cpu(vhdr->total_blocks);
  	HFSPLUS_SB(sb).free_blocks = be32_to_cpu(vhdr->free_blocks);
  	HFSPLUS_SB(sb).next_alloc = be32_to_cpu(vhdr->next_alloc);
  	HFSPLUS_SB(sb).next_cnid = be32_to_cpu(vhdr->next_cnid);
  	HFSPLUS_SB(sb).file_count = be32_to_cpu(vhdr->file_count);
  	HFSPLUS_SB(sb).folder_count = be32_to_cpu(vhdr->folder_count);
  	HFSPLUS_SB(sb).data_clump_blocks = be32_to_cpu(vhdr->data_clump_sz) >> HFSPLUS_SB(sb).alloc_blksz_shift;
  	if (!HFSPLUS_SB(sb).data_clump_blocks)
  		HFSPLUS_SB(sb).data_clump_blocks = 1;
  	HFSPLUS_SB(sb).rsrc_clump_blocks = be32_to_cpu(vhdr->rsrc_clump_sz) >> HFSPLUS_SB(sb).alloc_blksz_shift;
  	if (!HFSPLUS_SB(sb).rsrc_clump_blocks)
  		HFSPLUS_SB(sb).rsrc_clump_blocks = 1;
  
  	/* Set up operations so we can load metadata */
  	sb->s_op = &hfsplus_sops;
  	sb->s_maxbytes = MAX_LFS_FILESIZE;
  
  	if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {

  		printk(KERN_WARNING "hfs: Filesystem was not cleanly unmounted, "
  		       "running fsck.hfsplus is recommended.  mounting read-only.
  ");

  		sb->s_flags |= MS_RDONLY;

  	} else if (sbi->flags & HFSPLUS_SB_FORCE) {
  		/* nothing */

  	} else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {

  		printk(KERN_WARNING "hfs: Filesystem is marked locked, mounting read-only.
  ");

  		sb->s_flags |= MS_RDONLY;

  	} else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {

  		printk(KERN_WARNING "hfs: write access to a journaled filesystem is not supported, "

  		       "use the force option at your own risk, mounting read-only.
  ");

  		sb->s_flags |= MS_RDONLY;

  	}

  	sbi->flags &= ~HFSPLUS_SB_FORCE;

  
  	/* Load metadata objects (B*Trees) */
  	HFSPLUS_SB(sb).ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
  	if (!HFSPLUS_SB(sb).ext_tree) {

  		printk(KERN_ERR "hfs: failed to load extents file
  ");

  		goto cleanup;
  	}
  	HFSPLUS_SB(sb).cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
  	if (!HFSPLUS_SB(sb).cat_tree) {

  		printk(KERN_ERR "hfs: failed to load catalog file
  ");

  		goto cleanup;
  	}

  	inode = hfsplus_iget(sb, HFSPLUS_ALLOC_CNID);
  	if (IS_ERR(inode)) {

  		printk(KERN_ERR "hfs: failed to load allocation file
  ");

  		err = PTR_ERR(inode);

  		goto cleanup;
  	}

  	HFSPLUS_SB(sb).alloc_file = inode;

  
  	/* Load the root directory */

  	root = hfsplus_iget(sb, HFSPLUS_ROOT_CNID);
  	if (IS_ERR(root)) {
  		printk(KERN_ERR "hfs: failed to load root directory
  ");
  		err = PTR_ERR(root);
  		goto cleanup;
  	}

  	sb->s_root = d_alloc_root(root);
  	if (!sb->s_root) {

  		iput(root);

  		err = -ENOMEM;

  		goto cleanup;
  	}

  	sb->s_root->d_op = &hfsplus_dentry_operations;

  
  	str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
  	str.name = HFSP_HIDDENDIR_NAME;
  	hfs_find_init(HFSPLUS_SB(sb).cat_tree, &fd);
  	hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
  	if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
  		hfs_find_exit(&fd);
  		if (entry.type != cpu_to_be16(HFSPLUS_FOLDER))
  			goto cleanup;

  		inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id));
  		if (IS_ERR(inode)) {
  			err = PTR_ERR(inode);

  			goto cleanup;

  		}
  		HFSPLUS_SB(sb).hidden_dir = inode;

  	} else
  		hfs_find_exit(&fd);
  
  	if (sb->s_flags & MS_RDONLY)
  		goto out;
  
  	/* H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused
  	 * all three are registered with Apple for our use
  	 */
  	vhdr->last_mount_vers = cpu_to_be32(HFSP_MOUNT_VERSION);
  	vhdr->modify_date = hfsp_now2mt();

  	be32_add_cpu(&vhdr->write_count, 1);

  	vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_UNMNT);
  	vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_INCNSTNT);
  	mark_buffer_dirty(HFSPLUS_SB(sb).s_vhbh);

  	sync_dirty_buffer(HFSPLUS_SB(sb).s_vhbh);

  
  	if (!HFSPLUS_SB(sb).hidden_dir) {

  		printk(KERN_DEBUG "hfs: create hidden dir...
  ");

  		HFSPLUS_SB(sb).hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
  		hfsplus_create_cat(HFSPLUS_SB(sb).hidden_dir->i_ino, sb->s_root->d_inode,
  				   &str, HFSPLUS_SB(sb).hidden_dir);
  		mark_inode_dirty(HFSPLUS_SB(sb).hidden_dir);
  	}
  out:
  	unload_nls(sbi->nls);
  	sbi->nls = nls;
  	return 0;
  
  cleanup:
  	hfsplus_put_super(sb);
  	if (nls)
  		unload_nls(nls);
  	return err;
  }
  
  MODULE_AUTHOR("Brad Boyer");
  MODULE_DESCRIPTION("Extended Macintosh Filesystem");
  MODULE_LICENSE("GPL");

  static struct kmem_cache *hfsplus_inode_cachep;

  
  static struct inode *hfsplus_alloc_inode(struct super_block *sb)
  {
  	struct hfsplus_inode_info *i;

  	i = kmem_cache_alloc(hfsplus_inode_cachep, GFP_KERNEL);

  	return i ? &i->vfs_inode : NULL;
  }
  
  static void hfsplus_destroy_inode(struct inode *inode)
  {
  	kmem_cache_free(hfsplus_inode_cachep, &HFSPLUS_I(inode));
  }
  
  #define HFSPLUS_INODE_SIZE	sizeof(struct hfsplus_inode_info)

  static int hfsplus_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, hfsplus_fill_super,
  			   mnt);

  }
  
  static struct file_system_type hfsplus_fs_type = {
  	.owner		= THIS_MODULE,
  	.name		= "hfsplus",
  	.get_sb		= hfsplus_get_sb,
  	.kill_sb	= kill_block_super,
  	.fs_flags	= FS_REQUIRES_DEV,
  };

  static void hfsplus_init_once(void *p)

  {
  	struct hfsplus_inode_info *i = p;

  	inode_init_once(&i->vfs_inode);

  }
  
  static int __init init_hfsplus_fs(void)
  {
  	int err;
  
  	hfsplus_inode_cachep = kmem_cache_create("hfsplus_icache",
  		HFSPLUS_INODE_SIZE, 0, SLAB_HWCACHE_ALIGN,

  		hfsplus_init_once);

  	if (!hfsplus_inode_cachep)
  		return -ENOMEM;
  	err = register_filesystem(&hfsplus_fs_type);
  	if (err)
  		kmem_cache_destroy(hfsplus_inode_cachep);
  	return err;
  }
  
  static void __exit exit_hfsplus_fs(void)
  {
  	unregister_filesystem(&hfsplus_fs_type);

  	kmem_cache_destroy(hfsplus_inode_cachep);

  }
  
  module_init(init_hfsplus_fs)
  module_exit(exit_hfsplus_fs)