inode.c

Linux中使用的苹果的Macintosh文件系统源代码

		inode->i_ino = be32_to_cpu(rec->file.FlNum);
		inode->i_mode = S_IRUGO | S_IXUGO;
		if (!(rec->file.Flags & HFS_FIL_LOCK))
			inode->i_mode |= S_IWUGO;
		inode->i_mode &= ~hsb->s_file_umask;
		inode->i_mode |= S_IFREG;
		inode->i_ctime = inode->i_atime = inode->i_mtime =
				hfs_m_to_utime(rec->file.MdDat);
		inode->i_op = &hfs_file_inode_operations;
		inode->i_fop = &hfs_file_operations;
		inode->i_mapping->a_ops = &hfs_aops;
		break;
	case HFS_CDR_DIR:
		inode->i_ino = be32_to_cpu(rec->dir.DirID);
		inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
		HFS_I(inode)->fs_blocks = 0;
		inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask);
		inode->i_ctime = inode->i_atime = inode->i_mtime =
				hfs_m_to_utime(rec->dir.MdDat);
		inode->i_op = &hfs_dir_inode_operations;
		inode->i_fop = &hfs_dir_operations;
		break;
	default:
		make_bad_inode(inode);
	}
	return 0;
}

/*
 * __hfs_iget()
 *
 * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
 * the catalog B-tree and the 'type' of the desired file return the
 * inode for that file/directory or NULL.  Note that 'type' indicates
 * whether we want the actual file or directory, or the corresponding
 * metadata (AppleDouble header file or CAP metadata file).
 */
struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
{
	struct hfs_iget_data data = { key, rec };
	struct inode *inode;
	u32 cnid;

	switch (rec->type) {
	case HFS_CDR_DIR:
		cnid = be32_to_cpu(rec->dir.DirID);
		break;
	case HFS_CDR_FIL:
		cnid = be32_to_cpu(rec->file.FlNum);
		break;
	default:
		return NULL;
	}
	inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
	if (inode && (inode->i_state & I_NEW))
		unlock_new_inode(inode);
	return inode;
}

void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
			  __be32 *log_size, __be32 *phys_size)
{
	memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));

	if (log_size)
		*log_size = cpu_to_be32(inode->i_size);
	if (phys_size)
		*phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
					 HFS_SB(inode->i_sb)->alloc_blksz);
}

int hfs_write_inode(struct inode *inode, int unused)
{
	struct inode *main_inode = inode;
	struct hfs_find_data fd;
	hfs_cat_rec rec;

	dprint(DBG_INODE, "hfs_write_inode: %lu\n", inode->i_ino);
	hfs_ext_write_extent(inode);

	if (inode->i_ino < HFS_FIRSTUSER_CNID) {
		switch (inode->i_ino) {
		case HFS_ROOT_CNID:
			break;
		case HFS_EXT_CNID:
			hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
			return 0;
		case HFS_CAT_CNID:
			hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
			return 0;
		default:
			BUG();
			return -EIO;
		}
	}

	if (HFS_IS_RSRC(inode))
		main_inode = HFS_I(inode)->rsrc_inode;

	if (!main_inode->i_nlink)
		return 0;

	if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd))
		/* panic? */
		return -EIO;

	fd.search_key->cat = HFS_I(main_inode)->cat_key;
	if (hfs_brec_find(&fd))
		/* panic? */
		goto out;

	if (S_ISDIR(main_inode->i_mode)) {
		if (fd.entrylength < sizeof(struct hfs_cat_dir))
			/* panic? */;
		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
			   sizeof(struct hfs_cat_dir));
		if (rec.type != HFS_CDR_DIR ||
		    be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
		}

		rec.dir.MdDat = hfs_u_to_mtime(inode->i_mtime);
		rec.dir.Val = cpu_to_be16(inode->i_size - 2);

		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
			    sizeof(struct hfs_cat_dir));
	} else if (HFS_IS_RSRC(inode)) {
		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
			       sizeof(struct hfs_cat_file));
		hfs_inode_write_fork(inode, rec.file.RExtRec,
				     &rec.file.RLgLen, &rec.file.RPyLen);
		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
				sizeof(struct hfs_cat_file));
	} else {
		if (fd.entrylength < sizeof(struct hfs_cat_file))
			/* panic? */;
		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
			   sizeof(struct hfs_cat_file));
		if (rec.type != HFS_CDR_FIL ||
		    be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
		}

		if (inode->i_mode & S_IWUSR)
			rec.file.Flags &= ~HFS_FIL_LOCK;
		else
			rec.file.Flags |= HFS_FIL_LOCK;
		hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
		rec.file.MdDat = hfs_u_to_mtime(inode->i_mtime);

		hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
			    sizeof(struct hfs_cat_file));
	}
out:
	hfs_find_exit(&fd);
	return 0;
}

static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
				      struct nameidata *nd)
{
	struct inode *inode = NULL;
	hfs_cat_rec rec;
	struct hfs_find_data fd;
	int res;

	if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
		goto out;

	inode = HFS_I(dir)->rsrc_inode;
	if (inode)
		goto out;

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

	hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
	fd.search_key->cat = HFS_I(dir)->cat_key;
	res = hfs_brec_read(&fd, &rec, sizeof(rec));
	if (!res) {
		struct hfs_iget_data idata = { NULL, &rec };
		hfs_read_inode(inode, &idata);
	}
	hfs_find_exit(&fd);
	if (res) {
		iput(inode);
		return ERR_PTR(res);
	}
	HFS_I(inode)->rsrc_inode = dir;
	HFS_I(dir)->rsrc_inode = inode;
	igrab(dir);
	hlist_add_head(&inode->i_hash, &HFS_SB(dir->i_sb)->rsrc_inodes);
	mark_inode_dirty(inode);
out:
	d_add(dentry, inode);
	return NULL;
}

void hfs_clear_inode(struct inode *inode)
{
	if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
		HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
		iput(HFS_I(inode)->rsrc_inode);
	}
}

static int hfs_file_open(struct inode *inode, struct file *file)
{
	if (HFS_IS_RSRC(inode))
		inode = HFS_I(inode)->rsrc_inode;
	atomic_inc(&HFS_I(inode)->opencnt);
	return 0;
}

static int hfs_file_release(struct inode *inode, struct file *file)
{
	//struct super_block *sb = inode->i_sb;

	if (HFS_IS_RSRC(inode))
		inode = HFS_I(inode)->rsrc_inode;
	if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
		mutex_lock(&inode->i_mutex);
		hfs_file_truncate(inode);
		//if (inode->i_flags & S_DEAD) {
		//	hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
		//	hfs_delete_inode(inode);
		//}
		mutex_unlock(&inode->i_mutex);
	}
	return 0;
}

/*
 * hfs_notify_change()
 *
 * Based very closely on fs/msdos/inode.c by Werner Almesberger
 *
 * This is the notify_change() field in the super_operations structure
 * for HFS file systems.  The purpose is to take that changes made to
 * an inode and apply then in a filesystem-dependent manner.  In this
 * case the process has a few of tasks to do:
 *  1) prevent changes to the i_uid and i_gid fields.
 *  2) map file permissions to the closest allowable permissions
 *  3) Since multiple Linux files can share the same on-disk inode under
 *     HFS (for instance the data and resource forks of a file) a change
 *     to permissions must be applied to all other in-core inodes which
 *     correspond to the same HFS file.
 */

int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
{
	struct inode *inode = dentry->d_inode;
	struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
	int error;

	error = inode_change_ok(inode, attr); /* basic permission checks */
	if (error)
		return error;

	/* no uig/gid changes and limit which mode bits can be set */
	if (((attr->ia_valid & ATTR_UID) &&
	     (attr->ia_uid != hsb->s_uid)) ||
	    ((attr->ia_valid & ATTR_GID) &&
	     (attr->ia_gid != hsb->s_gid)) ||
	    ((attr->ia_valid & ATTR_MODE) &&
	     ((S_ISDIR(inode->i_mode) &&
	       (attr->ia_mode != inode->i_mode)) ||
	      (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
		return hsb->s_quiet ? 0 : error;
	}

	if (attr->ia_valid & ATTR_MODE) {
		/* Only the 'w' bits can ever change and only all together. */
		if (attr->ia_mode & S_IWUSR)
			attr->ia_mode = inode->i_mode | S_IWUGO;
		else
			attr->ia_mode = inode->i_mode & ~S_IWUGO;
		attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
	}
	error = inode_setattr(inode, attr);
	if (error)
		return error;

	return 0;
}


static const struct file_operations hfs_file_operations = {
	.llseek		= generic_file_llseek,
	.read		= do_sync_read,
	.aio_read	= generic_file_aio_read,
	.write		= do_sync_write,
	.aio_write	= generic_file_aio_write,
	.mmap		= generic_file_mmap,
	.splice_read	= generic_file_splice_read,
	.fsync		= file_fsync,
	.open		= hfs_file_open,
	.release	= hfs_file_release,
};

static const struct inode_operations hfs_file_inode_operations = {
	.lookup		= hfs_file_lookup,
	.truncate	= hfs_file_truncate,
	.setattr	= hfs_inode_setattr,
	.setxattr	= hfs_setxattr,
	.getxattr	= hfs_getxattr,
	.listxattr	= hfs_listxattr,
};