/*
   *  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/blkdev.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"

  static int hfsplus_system_read_inode(struct inode *inode)
  {
  	struct hfsplus_vh *vhdr = HFSPLUS_SB(inode->i_sb)->s_vhdr;
  
  	switch (inode->i_ino) {
  	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:
  		return -EIO;
  	}
  
  	return 0;
  }

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

  {
  	struct hfs_find_data fd;

  	struct inode *inode;

  	int err;

  
  	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)->extent_state = 0;

  	HFSPLUS_I(inode)->rsrc_inode = NULL;
  	atomic_set(&HFSPLUS_I(inode)->opencnt, 0);

  	if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
  	    inode->i_ino == HFSPLUS_ROOT_CNID) {

  		err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
  		if (!err) {
  			err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
  			if (!err)
  				err = hfsplus_cat_read_inode(inode, &fd);
  			hfs_find_exit(&fd);
  		}

  	} else {
  		err = hfsplus_system_read_inode(inode);

  	}

  
  	if (err) {
  		iget_failed(inode);
  		return ERR_PTR(err);

  	}

  	unlock_new_inode(inode);
  	return inode;

  }

  static int hfsplus_system_write_inode(struct inode *inode)

  {

  	struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);

  	struct hfsplus_vh *vhdr = sbi->s_vhdr;
  	struct hfsplus_fork_raw *fork;
  	struct hfs_btree *tree = NULL;

  	switch (inode->i_ino) {

  	case HFSPLUS_EXT_CNID:

  		fork = &vhdr->ext_file;
  		tree = sbi->ext_tree;

  		break;
  	case HFSPLUS_CAT_CNID:

  		fork = &vhdr->cat_file;
  		tree = sbi->cat_tree;

  		break;
  	case HFSPLUS_ALLOC_CNID:

  		fork = &vhdr->alloc_file;

  		break;
  	case HFSPLUS_START_CNID:

  		fork = &vhdr->start_file;

  		break;
  	case HFSPLUS_ATTR_CNID:

  		fork = &vhdr->attr_file;
  		tree = sbi->attr_tree;
  	default:
  		return -EIO;
  	}
  
  	if (fork->total_size != cpu_to_be64(inode->i_size)) {

  		set_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags);

  		inode->i_sb->s_dirt = 1;

  	}

  	hfsplus_inode_write_fork(inode, fork);
  	if (tree)
  		hfs_btree_write(tree);
  	return 0;
  }
  
  static int hfsplus_write_inode(struct inode *inode,
  		struct writeback_control *wbc)
  {

  	int err;

  	dprint(DBG_INODE, "hfsplus_write_inode: %lu
  ", inode->i_ino);

  	err = hfsplus_ext_write_extent(inode);
  	if (err)
  		return err;

  
  	if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
  	    inode->i_ino == HFSPLUS_ROOT_CNID)
  		return hfsplus_cat_write_inode(inode);
  	else
  		return hfsplus_system_write_inode(inode);

  }

  static void hfsplus_evict_inode(struct inode *inode)

  {

  	dprint(DBG_INODE, "hfsplus_evict_inode: %lu
  ", inode->i_ino);
  	truncate_inode_pages(&inode->i_data, 0);
  	end_writeback(inode);

  	if (HFSPLUS_IS_RSRC(inode)) {

  		HFSPLUS_I(HFSPLUS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
  		iput(HFSPLUS_I(inode)->rsrc_inode);

  	}

  }

  int hfsplus_sync_fs(struct super_block *sb, int wait)

  {

  	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
  	struct hfsplus_vh *vhdr = sbi->s_vhdr;

  	int write_backup = 0;
  	int error, error2;

  	if (!wait)
  		return 0;

  
  	dprint(DBG_SUPER, "hfsplus_write_super
  ");

  	sb->s_dirt = 0;

  	/*
  	 * Explicitly write out the special metadata inodes.
  	 *
  	 * While these special inodes are marked as hashed and written
  	 * out peridocically by the flusher threads we redirty them
  	 * during writeout of normal inodes, and thus the life lock
  	 * prevents us from getting the latest state to disk.
  	 */
  	error = filemap_write_and_wait(sbi->cat_tree->inode->i_mapping);
  	error2 = filemap_write_and_wait(sbi->ext_tree->inode->i_mapping);
  	if (!error)
  		error = error2;
  	error2 = filemap_write_and_wait(sbi->alloc_file->i_mapping);
  	if (!error)
  		error = error2;

  	mutex_lock(&sbi->vh_mutex);
  	mutex_lock(&sbi->alloc_mutex);

  	vhdr->free_blocks = cpu_to_be32(sbi->free_blocks);

  	vhdr->next_cnid = cpu_to_be32(sbi->next_cnid);
  	vhdr->folder_count = cpu_to_be32(sbi->folder_count);
  	vhdr->file_count = cpu_to_be32(sbi->file_count);

  	if (test_and_clear_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags)) {

  		memcpy(sbi->s_backup_vhdr, sbi->s_vhdr, sizeof(*sbi->s_vhdr));
  		write_backup = 1;

  	}

  	error2 = hfsplus_submit_bio(sb,

  				   sbi->part_start + HFSPLUS_VOLHEAD_SECTOR,

  				   sbi->s_vhdr_buf, NULL, WRITE_SYNC);

  	if (!error)
  		error = error2;

  	if (!write_backup)
  		goto out;

  	error2 = hfsplus_submit_bio(sb,

  				  sbi->part_start + sbi->sect_count - 2,

  				  sbi->s_backup_vhdr_buf, NULL, WRITE_SYNC);

  	if (!error)
  		error2 = error;
  out:

  	mutex_unlock(&sbi->alloc_mutex);

  	mutex_unlock(&sbi->vh_mutex);

  
  	if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags))
  		blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);

  	return error;

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

  }
  
  static void hfsplus_put_super(struct super_block *sb)
  {

  	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);

  	dprint(DBG_SUPER, "hfsplus_put_super
  ");

  	if (!sb->s_fs_info)
  		return;

  	if (!(sb->s_flags & MS_RDONLY) && sbi->s_vhdr) {
  		struct hfsplus_vh *vhdr = sbi->s_vhdr;

  
  		vhdr->modify_date = hfsp_now2mt();
  		vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
  		vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);

  
  		hfsplus_sync_fs(sb, 1);

  	}

  	hfs_btree_close(sbi->cat_tree);
  	hfs_btree_close(sbi->ext_tree);
  	iput(sbi->alloc_file);
  	iput(sbi->hidden_dir);

  	kfree(sbi->s_vhdr_buf);
  	kfree(sbi->s_backup_vhdr_buf);

  	unload_nls(sbi->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;

  	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);

  	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);

  	buf->f_type = HFSPLUS_SUPER_MAGIC;
  	buf->f_bsize = sb->s_blocksize;

  	buf->f_blocks = sbi->total_blocks << sbi->fs_shift;
  	buf->f_bfree = sbi->free_blocks << sbi->fs_shift;

  	buf->f_bavail = buf->f_bfree;
  	buf->f_files = 0xFFFFFFFF;

  	buf->f_ffree = 0xFFFFFFFF - sbi->next_cnid;

  	buf->f_fsid.val[0] = (u32)id;
  	buf->f_fsid.val[1] = (u32)(id >> 32);

  	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;

  		int force = 0;

  		if (!hfsplus_parse_options_remount(data, &force))

  			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 (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,

  	.evict_inode	= hfsplus_evict_inode,

  	.put_super	= hfsplus_put_super,
  	.write_super	= hfsplus_write_super,

  	.sync_fs	= hfsplus_sync_fs,

  	.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;

  	u64 last_fs_block, last_fs_page;

  	int err;

  	err = -EINVAL;

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

  	if (!sbi)

  		goto out;

  	sb->s_fs_info = sbi;

  	mutex_init(&sbi->alloc_mutex);

  	mutex_init(&sbi->vh_mutex);

  	hfsplus_fill_defaults(sbi);

  
  	err = -EINVAL;

  	if (!hfsplus_parse_options(data, sbi)) {

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

  		goto out_unload_nls;

  	}
  
  	/* 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
  ");

  		goto out_unload_nls;

  	}
  
  	/* Grab the volume header */
  	if (hfsplus_read_wrapper(sb)) {
  		if (!silent)

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

  		goto out_unload_nls;

  	}

  	vhdr = sbi->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 out_free_vhdr;

  	}

  	sbi->total_blocks = be32_to_cpu(vhdr->total_blocks);
  	sbi->free_blocks = be32_to_cpu(vhdr->free_blocks);

  	sbi->next_cnid = be32_to_cpu(vhdr->next_cnid);
  	sbi->file_count = be32_to_cpu(vhdr->file_count);
  	sbi->folder_count = be32_to_cpu(vhdr->folder_count);
  	sbi->data_clump_blocks =
  		be32_to_cpu(vhdr->data_clump_sz) >> sbi->alloc_blksz_shift;
  	if (!sbi->data_clump_blocks)
  		sbi->data_clump_blocks = 1;
  	sbi->rsrc_clump_blocks =
  		be32_to_cpu(vhdr->rsrc_clump_sz) >> sbi->alloc_blksz_shift;
  	if (!sbi->rsrc_clump_blocks)
  		sbi->rsrc_clump_blocks = 1;

  	err = -EFBIG;
  	last_fs_block = sbi->total_blocks - 1;
  	last_fs_page = (last_fs_block << sbi->alloc_blksz_shift) >>
  			PAGE_CACHE_SHIFT;
  
  	if ((last_fs_block > (sector_t)(~0ULL) >> (sbi->alloc_blksz_shift - 9)) ||
  	    (last_fs_page > (pgoff_t)(~0ULL))) {

  		printk(KERN_ERR "hfs: filesystem size too large.
  ");
  		goto out_free_vhdr;
  	}

  	/* 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 (test_and_clear_bit(HFSPLUS_SB_FORCE, &sbi->flags)) {

  		/* 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)) &&
  			!(sb->s_flags & MS_RDONLY)) {
  		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;

  	}

  	err = -EINVAL;

  	/* Load metadata objects (B*Trees) */

  	sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
  	if (!sbi->ext_tree) {

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

  		goto out_free_vhdr;

  	}

  	sbi->cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
  	if (!sbi->cat_tree) {

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

  		goto out_close_ext_tree;

  	}

  	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 out_close_cat_tree;

  	}

  	sbi->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 out_put_alloc_file;

  	}
  
  	str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
  	str.name = HFSP_HIDDENDIR_NAME;

  	err = hfs_find_init(sbi->cat_tree, &fd);
  	if (err)
  		goto out_put_root;

  	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 out_put_root;

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

  			goto out_put_root;

  		}

  		sbi->hidden_dir = inode;

  	} else
  		hfs_find_exit(&fd);

  	if (!(sb->s_flags & MS_RDONLY)) {
  		/*
  		 * 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);
  		hfsplus_sync_fs(sb, 1);

  		if (!sbi->hidden_dir) {
  			mutex_lock(&sbi->vh_mutex);
  			sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);

  			if (!sbi->hidden_dir) {
  				mutex_unlock(&sbi->vh_mutex);
  				err = -ENOMEM;
  				goto out_put_root;
  			}
  			err = hfsplus_create_cat(sbi->hidden_dir->i_ino, root,
  						 &str, sbi->hidden_dir);

  			mutex_unlock(&sbi->vh_mutex);

  			if (err)
  				goto out_put_hidden_dir;

  
  			hfsplus_mark_inode_dirty(sbi->hidden_dir,
  						 HFSPLUS_I_CAT_DIRTY);
  		}

  	}

  
  	sb->s_d_op = &hfsplus_dentry_operations;
  	sb->s_root = d_alloc_root(root);
  	if (!sb->s_root) {
  		err = -ENOMEM;
  		goto out_put_hidden_dir;
  	}

  	unload_nls(sbi->nls);
  	sbi->nls = nls;
  	return 0;

  out_put_hidden_dir:
  	iput(sbi->hidden_dir);
  out_put_root:

  	iput(root);

  out_put_alloc_file:
  	iput(sbi->alloc_file);
  out_close_cat_tree:
  	hfs_btree_close(sbi->cat_tree);
  out_close_ext_tree:
  	hfs_btree_close(sbi->ext_tree);
  out_free_vhdr:

  	kfree(sbi->s_vhdr_buf);
  	kfree(sbi->s_backup_vhdr_buf);

  out_unload_nls:
  	unload_nls(sbi->nls);

  	unload_nls(nls);

  	kfree(sbi);
  out:

  	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_i_callback(struct rcu_head *head)

  {

  	struct inode *inode = container_of(head, struct inode, i_rcu);

  	kmem_cache_free(hfsplus_inode_cachep, HFSPLUS_I(inode));

  }

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

  #define HFSPLUS_INODE_SIZE	sizeof(struct hfsplus_inode_info)

  static struct dentry *hfsplus_mount(struct file_system_type *fs_type,
  			  int flags, const char *dev_name, void *data)

  {

  	return mount_bdev(fs_type, flags, dev_name, data, hfsplus_fill_super);

  }
  
  static struct file_system_type hfsplus_fs_type = {
  	.owner		= THIS_MODULE,
  	.name		= "hfsplus",

  	.mount		= hfsplus_mount,

  	.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)