| /* |
| * 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 <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, *inode_buf; |
| int csum_flag = 0; |
| blk_t blk; |
| blk_t blk_itr = 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_BLOCKS_PER_GROUP(fs->super) / 8; |
| retval = ext2fs_get_memalign(fs->blocksize, fs->blocksize, |
| &block_buf); |
| if (retval) |
| return retval; |
| 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) |
| return retval; |
| 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 && fs->group_desc[i].bg_flags & |
| EXT2_BG_BLOCK_UNINIT) |
| goto skip_this_block_bitmap; |
| |
| retval = ext2fs_get_block_bitmap_range(fs->block_map, |
| blk_itr, block_nbytes << 3, block_buf); |
| if (retval) |
| return retval; |
| |
| if (i == fs->group_desc_count - 1) { |
| /* Force bitmap padding for the last group */ |
| nbits = ((fs->super->s_blocks_count |
| - fs->super->s_first_data_block) |
| % EXT2_BLOCKS_PER_GROUP(fs->super)); |
| if (nbits) |
| for (j = nbits; j < fs->blocksize * 8; j++) |
| ext2fs_set_bit(j, block_buf); |
| } |
| blk = fs->group_desc[i].bg_block_bitmap; |
| if (blk) { |
| retval = io_channel_write_blk(fs->io, blk, 1, |
| block_buf); |
| if (retval) |
| return EXT2_ET_BLOCK_BITMAP_WRITE; |
| } |
| skip_this_block_bitmap: |
| blk_itr += block_nbytes << 3; |
| skip_block_bitmap: |
| |
| if (!do_inode) |
| continue; |
| |
| if (csum_flag && fs->group_desc[i].bg_flags & |
| EXT2_BG_INODE_UNINIT) |
| goto skip_this_inode_bitmap; |
| |
| retval = ext2fs_get_inode_bitmap_range(fs->inode_map, |
| ino_itr, inode_nbytes << 3, inode_buf); |
| if (retval) |
| return retval; |
| |
| blk = fs->group_desc[i].bg_inode_bitmap; |
| if (blk) { |
| retval = io_channel_write_blk(fs->io, blk, 1, |
| inode_buf); |
| if (retval) |
| return EXT2_ET_INODE_BITMAP_WRITE; |
| } |
| 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; |
| } |
| |
| 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_BLOCKS_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; |
| blk_t blk; |
| blk_t blk_itr = fs->super->s_first_data_block; |
| blk_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_blk(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_range(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 = EXT2_BLOCKS_PER_GROUP(fs->super) * |
| fs->group_desc_count; |
| while (block_nbytes > 0) { |
| retval = io_channel_read_blk(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_range(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 = fs->group_desc[i].bg_block_bitmap; |
| if (csum_flag && fs->group_desc[i].bg_flags & |
| EXT2_BG_BLOCK_UNINIT && |
| ext2fs_group_desc_csum_verify(fs, i)) |
| blk = 0; |
| if (blk) { |
| retval = io_channel_read_blk(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_range(fs->block_map, |
| blk_itr, cnt, block_bitmap); |
| if (retval) |
| goto cleanup; |
| blk_itr += block_nbytes << 3; |
| } |
| if (inode_bitmap) { |
| blk = fs->group_desc[i].bg_inode_bitmap; |
| if (csum_flag && fs->group_desc[i].bg_flags & |
| EXT2_BG_INODE_UNINIT && |
| ext2fs_group_desc_csum_verify(fs, i)) |
| blk = 0; |
| if (blk) { |
| retval = io_channel_read_blk(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_range(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); |
| } |