/* * rw_bitmaps.c --- routines to read and write the inode and block bitmaps. * * Copyright (C) 1993, 1994, 1994, 1996 Theodore Ts'o. * * %Begin-Header% * This file may be redistributed under the terms of the GNU Library * General Public License, version 2. * %End-Header% */ #include "config.h" #include <stdio.h> #include <string.h> #if HAVE_UNISTD_H #include <unistd.h> #endif #include <fcntl.h> #include <time.h> #ifdef HAVE_SYS_STAT_H #include <sys/stat.h> #endif #ifdef HAVE_SYS_TYPES_H #include <sys/types.h> #endif #include "ext2_fs.h" #include "ext2fs.h" #include "e2image.h" static errcode_t write_bitmaps(ext2_filsys fs, int do_inode, int do_block) { dgrp_t i; unsigned int j; int block_nbytes, inode_nbytes; unsigned int nbits; errcode_t retval; char *block_buf = NULL, *inode_buf = NULL; int csum_flag = 0; blk64_t blk; blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block); ext2_ino_t ino_itr = 1; EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); if (!(fs->flags & EXT2_FLAG_RW)) return EXT2_ET_RO_FILSYS; if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) csum_flag = 1; inode_nbytes = block_nbytes = 0; if (do_block) { block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8; retval = ext2fs_get_memalign(fs->blocksize, fs->blocksize, &block_buf); if (retval) goto errout; memset(block_buf, 0xff, fs->blocksize); } if (do_inode) { inode_nbytes = (size_t) ((EXT2_INODES_PER_GROUP(fs->super)+7) / 8); retval = ext2fs_get_memalign(fs->blocksize, fs->blocksize, &inode_buf); if (retval) goto errout; memset(inode_buf, 0xff, fs->blocksize); } for (i = 0; i < fs->group_desc_count; i++) { if (!do_block) goto skip_block_bitmap; if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT) ) goto skip_this_block_bitmap; retval = ext2fs_get_block_bitmap_range2(fs->block_map, blk_itr, block_nbytes << 3, block_buf); if (retval) goto errout; if (i == fs->group_desc_count - 1) { /* Force bitmap padding for the last group */ nbits = EXT2FS_NUM_B2C(fs, ((ext2fs_blocks_count(fs->super) - (__u64) fs->super->s_first_data_block) % (__u64) EXT2_BLOCKS_PER_GROUP(fs->super))); if (nbits) for (j = nbits; j < fs->blocksize * 8; j++) ext2fs_set_bit(j, block_buf); } blk = ext2fs_block_bitmap_loc(fs, i); if (blk) { retval = io_channel_write_blk64(fs->io, blk, 1, block_buf); if (retval) { retval = EXT2_ET_BLOCK_BITMAP_WRITE; goto errout; } } skip_this_block_bitmap: blk_itr += block_nbytes << 3; skip_block_bitmap: if (!do_inode) continue; if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT) ) goto skip_this_inode_bitmap; retval = ext2fs_get_inode_bitmap_range2(fs->inode_map, ino_itr, inode_nbytes << 3, inode_buf); if (retval) goto errout; blk = ext2fs_inode_bitmap_loc(fs, i); if (blk) { retval = io_channel_write_blk64(fs->io, blk, 1, inode_buf); if (retval) { retval = EXT2_ET_INODE_BITMAP_WRITE; goto errout; } } skip_this_inode_bitmap: ino_itr += inode_nbytes << 3; } if (do_block) { fs->flags &= ~EXT2_FLAG_BB_DIRTY; ext2fs_free_mem(&block_buf); } if (do_inode) { fs->flags &= ~EXT2_FLAG_IB_DIRTY; ext2fs_free_mem(&inode_buf); } return 0; errout: if (inode_buf) ext2fs_free_mem(&inode_buf); if (block_buf) ext2fs_free_mem(&block_buf); return retval; } static errcode_t read_bitmaps(ext2_filsys fs, int do_inode, int do_block) { dgrp_t i; char *block_bitmap = 0, *inode_bitmap = 0; char *buf; errcode_t retval; int block_nbytes = EXT2_CLUSTERS_PER_GROUP(fs->super) / 8; int inode_nbytes = EXT2_INODES_PER_GROUP(fs->super) / 8; int csum_flag = 0; int do_image = fs->flags & EXT2_FLAG_IMAGE_FILE; unsigned int cnt; blk64_t blk; blk64_t blk_itr = EXT2FS_B2C(fs, fs->super->s_first_data_block); blk64_t blk_cnt; ext2_ino_t ino_itr = 1; ext2_ino_t ino_cnt; EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); fs->write_bitmaps = ext2fs_write_bitmaps; if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) csum_flag = 1; retval = ext2fs_get_mem(strlen(fs->device_name) + 80, &buf); if (retval) return retval; if (do_block) { if (fs->block_map) ext2fs_free_block_bitmap(fs->block_map); strcpy(buf, "block bitmap for "); strcat(buf, fs->device_name); retval = ext2fs_allocate_block_bitmap(fs, buf, &fs->block_map); if (retval) goto cleanup; if (do_image) retval = ext2fs_get_mem(fs->blocksize, &block_bitmap); else retval = ext2fs_get_memalign((unsigned) block_nbytes, fs->blocksize, &block_bitmap); if (retval) goto cleanup; } else block_nbytes = 0; if (do_inode) { if (fs->inode_map) ext2fs_free_inode_bitmap(fs->inode_map); strcpy(buf, "inode bitmap for "); strcat(buf, fs->device_name); retval = ext2fs_allocate_inode_bitmap(fs, buf, &fs->inode_map); if (retval) goto cleanup; retval = ext2fs_get_mem(do_image ? fs->blocksize : (unsigned) inode_nbytes, &inode_bitmap); if (retval) goto cleanup; } else inode_nbytes = 0; ext2fs_free_mem(&buf); if (fs->flags & EXT2_FLAG_IMAGE_FILE) { blk = (fs->image_header->offset_inodemap / fs->blocksize); ino_cnt = fs->super->s_inodes_count; while (inode_nbytes > 0) { retval = io_channel_read_blk64(fs->image_io, blk++, 1, inode_bitmap); if (retval) goto cleanup; cnt = fs->blocksize << 3; if (cnt > ino_cnt) cnt = ino_cnt; retval = ext2fs_set_inode_bitmap_range2(fs->inode_map, ino_itr, cnt, inode_bitmap); if (retval) goto cleanup; ino_itr += fs->blocksize << 3; ino_cnt -= fs->blocksize << 3; inode_nbytes -= fs->blocksize; } blk = (fs->image_header->offset_blockmap / fs->blocksize); blk_cnt = (blk64_t)EXT2_CLUSTERS_PER_GROUP(fs->super) * fs->group_desc_count; while (block_nbytes > 0) { retval = io_channel_read_blk64(fs->image_io, blk++, 1, block_bitmap); if (retval) goto cleanup; cnt = fs->blocksize << 3; if (cnt > blk_cnt) cnt = blk_cnt; retval = ext2fs_set_block_bitmap_range2(fs->block_map, blk_itr, cnt, block_bitmap); if (retval) goto cleanup; blk_itr += fs->blocksize << 3; blk_cnt -= fs->blocksize << 3; block_nbytes -= fs->blocksize; } goto success_cleanup; } for (i = 0; i < fs->group_desc_count; i++) { if (block_bitmap) { blk = ext2fs_block_bitmap_loc(fs, i); if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_BLOCK_UNINIT) && ext2fs_group_desc_csum_verify(fs, i)) blk = 0; if (blk) { retval = io_channel_read_blk64(fs->io, blk, -block_nbytes, block_bitmap); if (retval) { retval = EXT2_ET_BLOCK_BITMAP_READ; goto cleanup; } } else memset(block_bitmap, 0, block_nbytes); cnt = block_nbytes << 3; retval = ext2fs_set_block_bitmap_range2(fs->block_map, blk_itr, cnt, block_bitmap); if (retval) goto cleanup; blk_itr += block_nbytes << 3; } if (inode_bitmap) { blk = ext2fs_inode_bitmap_loc(fs, i); if (csum_flag && ext2fs_bg_flags_test(fs, i, EXT2_BG_INODE_UNINIT) && ext2fs_group_desc_csum_verify(fs, i)) blk = 0; if (blk) { retval = io_channel_read_blk64(fs->io, blk, -inode_nbytes, inode_bitmap); if (retval) { retval = EXT2_ET_INODE_BITMAP_READ; goto cleanup; } } else memset(inode_bitmap, 0, inode_nbytes); cnt = inode_nbytes << 3; retval = ext2fs_set_inode_bitmap_range2(fs->inode_map, ino_itr, cnt, inode_bitmap); if (retval) goto cleanup; ino_itr += inode_nbytes << 3; } } success_cleanup: if (inode_bitmap) ext2fs_free_mem(&inode_bitmap); if (block_bitmap) ext2fs_free_mem(&block_bitmap); return 0; cleanup: if (do_block) { ext2fs_free_mem(&fs->block_map); fs->block_map = 0; } if (do_inode) { ext2fs_free_mem(&fs->inode_map); fs->inode_map = 0; } if (inode_bitmap) ext2fs_free_mem(&inode_bitmap); if (block_bitmap) ext2fs_free_mem(&block_bitmap); if (buf) ext2fs_free_mem(&buf); return retval; } errcode_t ext2fs_read_inode_bitmap(ext2_filsys fs) { return read_bitmaps(fs, 1, 0); } errcode_t ext2fs_read_block_bitmap(ext2_filsys fs) { return read_bitmaps(fs, 0, 1); } errcode_t ext2fs_write_inode_bitmap(ext2_filsys fs) { return write_bitmaps(fs, 1, 0); } errcode_t ext2fs_write_block_bitmap (ext2_filsys fs) { return write_bitmaps(fs, 0, 1); } errcode_t ext2fs_read_bitmaps(ext2_filsys fs) { if (fs->inode_map && fs->block_map) return 0; return read_bitmaps(fs, !fs->inode_map, !fs->block_map); } errcode_t ext2fs_write_bitmaps(ext2_filsys fs) { int do_inode = fs->inode_map && ext2fs_test_ib_dirty(fs); int do_block = fs->block_map && ext2fs_test_bb_dirty(fs); if (!do_inode && !do_block) return 0; return write_bitmaps(fs, do_inode, do_block); }