1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * Squashfs - a compressed read only filesystem for Linux
31  * Lookup offset (f_pos) in the directory index, returning the
32  * metadata block containing it.
35  * (if any) we have managed to read - the index isn't essential, just
42 	struct squashfs_sb_info *msblk = sb->s_fs_info;  in get_dir_index_using_offset()
52 	 * is offset by 3 because we invent "." and ".." entries which are  in get_dir_index_using_offset()
57 	f_pos -= 3;  in get_dir_index_using_offset()
85 					msblk->directory_table;  in get_dir_index_using_offset()
100 	struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;  in squashfs_readdir()
101 	u64 block = squashfs_i(inode)->start + msblk->directory_table;  in squashfs_readdir()  local
102 	int offset = squashfs_i(inode)->offset, length, err;  in squashfs_readdir()  local
107 	TRACE("Entered squashfs_readdir [%llx:%x]\n", block, offset);  in squashfs_readdir()
120 	 * It also means that the external f_pos is offset by 3 from the  in squashfs_readdir()
121 	 * on-disk directory f_pos.  in squashfs_readdir()
123 	while (ctx->pos < 3) {  in squashfs_readdir()
127 		if (ctx->pos == 0) {  in squashfs_readdir()
130 			i_ino = inode->i_ino;  in squashfs_readdir()
134 			i_ino = squashfs_i(inode)->parent;  in squashfs_readdir()
141 		ctx->pos += size;  in squashfs_readdir()
144 	length = get_dir_index_using_offset(inode->i_sb, &block, &offset,  in squashfs_readdir()
145 				squashfs_i(inode)->dir_idx_start,  in squashfs_readdir()
146 				squashfs_i(inode)->dir_idx_offset,  in squashfs_readdir()
147 				squashfs_i(inode)->dir_idx_cnt,  in squashfs_readdir()
148 				ctx->pos);  in squashfs_readdir()
154 		err = squashfs_read_metadata(inode->i_sb, &dirh, &block,  in squashfs_readdir()
155 					&offset, sizeof(dirh));  in squashfs_readdir()
166 		while (dir_count--) {  in squashfs_readdir()
170 			err = squashfs_read_metadata(inode->i_sb, dire, &block,  in squashfs_readdir()
171 					&offset, sizeof(*dire));  in squashfs_readdir()
175 			size = le16_to_cpu(dire->size) + 1;  in squashfs_readdir()
181 			err = squashfs_read_metadata(inode->i_sb, dire->name,  in squashfs_readdir()
182 					&block, &offset, size);  in squashfs_readdir()
188 			if (ctx->pos >= length)  in squashfs_readdir()
191 			dire->name[size] = '\0';  in squashfs_readdir()
193 				((short) le16_to_cpu(dire->inode_number));  in squashfs_readdir()
194 			type = le16_to_cpu(dire->type);  in squashfs_readdir()
199 			if (!dir_emit(ctx, dire->name, size,  in squashfs_readdir()
204 			ctx->pos = length;  in squashfs_readdir()
213 	ERROR("Unable to read directory block [%llx:%x]\n", block, offset);  in squashfs_readdir()