예제 #1
0
int empty_inline_dir(struct inode *dir, int *has_inline_data)
{
	int err, inline_size;
	struct ext4_iloc iloc;
	void *inline_pos;
	unsigned int offset;
	struct ext4_dir_entry_2 *de;
	int ret = 1;

	err = ext4_get_inode_loc(dir, &iloc);
	if (err) {
		EXT4_ERROR_INODE(dir, "error %d getting inode %lu block",
				 err, dir->i_ino);
		return 1;
	}

	down_read(&EXT4_I(dir)->xattr_sem);
	if (!ext4_has_inline_data(dir)) {
		*has_inline_data = 0;
		goto out;
	}

	de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
	if (!le32_to_cpu(de->inode)) {
		ext4_warning(dir->i_sb,
			     "bad inline directory (dir #%lu) - no `..'",
			     dir->i_ino);
		ret = 1;
		goto out;
	}

	offset = EXT4_INLINE_DOTDOT_SIZE;
	while (offset < dir->i_size) {
		de = ext4_get_inline_entry(dir, &iloc, offset,
					   &inline_pos, &inline_size);
		if (ext4_check_dir_entry(dir, NULL, de,
					 iloc.bh, inline_pos,
					 inline_size, offset)) {
			ext4_warning(dir->i_sb,
				     "bad inline directory (dir #%lu) - "
				     "inode %u, rec_len %u, name_len %d"
				     "inline size %d\n",
				     dir->i_ino, le32_to_cpu(de->inode),
				     le16_to_cpu(de->rec_len), de->name_len,
				     inline_size);
			ret = 1;
			goto out;
		}
		if (le32_to_cpu(de->inode)) {
			ret = 0;
			goto out;
		}
		offset += ext4_rec_len_from_disk(de->rec_len, inline_size);
	}

out:
	up_read(&EXT4_I(dir)->xattr_sem);
	brelse(iloc.bh);
	return ret;
}
예제 #2
0
int ext4_read_inline_dir(struct file *filp,
			 void *dirent, filldir_t filldir)
{
	int error = 0;
	unsigned int offset;
	int i, stored;
	void *inline_pos;
	struct ext4_dir_entry_2 *de;
	struct super_block *sb;
	struct inode *inode = filp->f_path.dentry->d_inode;
	int ret, inline_size = 0;
	struct ext4_iloc iloc;

	ret = ext4_get_inode_loc(inode, &iloc);
	if (ret)
		return ret;

	down_read(&EXT4_I(inode)->xattr_sem);
	if (!ext4_has_inline_data(inode))
		goto out;

	sb = inode->i_sb;
	stored = 0;
	offset = filp->f_pos & (sb->s_blocksize - 1);

	while (!error && !stored && filp->f_pos < inode->i_size) {
revalidate:
		/* If the version has changed since the last call to
		 * readdir(2), then we might be pointing to an invalid
		 * dirent right now.  Scan from the start of the block
		 * to make sure. */
		if (filp->f_version != inode->i_version) {
			for (i = 0; i < inode->i_size && i < offset; ) {
				de = ext4_get_inline_entry(inode, &iloc, i,
							   NULL, &inline_size);
				/* It's too expensive to do a full
				 * dirent test each time round this
				 * loop, but we do have to test at
				 * least that it is non-zero.  A
				 * failure will be detected in the
				 * dirent test below. */
				if (ext4_rec_len_from_disk(de->rec_len,
					inline_size) < EXT4_DIR_REC_LEN(1))
					break;
				i += ext4_rec_len_from_disk(de->rec_len,
							    inline_size);
			}
			offset = i;
			filp->f_pos = offset;
			filp->f_version = inode->i_version;
		}

		while (!error && filp->f_pos < inode->i_size) {
			de = ext4_get_inline_entry(inode, &iloc, offset,
						   &inline_pos, &inline_size);
			if (ext4_check_dir_entry(__func__, inode, de,
						 iloc.bh, inline_pos,
						 inline_size, offset)) {
				ret = stored;
				goto out;
			}
			offset += ext4_rec_len_from_disk(de->rec_len,
							 inline_size);
			if (le32_to_cpu(de->inode)) {
				/* We might block in the next section
				 * if the data destination is
				 * currently swapped out.  So, use a
				 * version stamp to detect whether or
				 * not the directory has been modified
				 * during the copy operation.
				 */
				u64 version = filp->f_version;

				error = filldir(dirent, de->name,
						de->name_len,
						filp->f_pos,
						le32_to_cpu(de->inode),
						get_dtype(sb, de->file_type));
				if (error)
					break;
				if (version != filp->f_version)
					goto revalidate;
				stored++;
			}
			filp->f_pos += ext4_rec_len_from_disk(de->rec_len,
							      inline_size);
		}
		offset = 0;
	}
out:
	up_read(&EXT4_I(inode)->xattr_sem);
	brelse(iloc.bh);
	return ret;
}