projects / thirdparty / e2fsprogs.git / blame
| Commit | Line | Data |
|---|---|---|
| ef344e13 | 1 | /* |
| efc6f628 | 2 | * alloc_sb.c --- Allocate the superblock and block group descriptors for a |
| ef344e13 TT |
3 | * newly initialized filesystem. Used by mke2fs when initializing a filesystem |
| 4 | * | |
| 5 | * Copyright (C) 1994, 1995, 1996, 2003 Theodore Ts'o. | |
| 6 | * | |
| 7 | * %Begin-Header% | |
| 8 | * This file may be redistributed under the terms of the GNU Public | |
| 9 | * License. | |
| 10 | * %End-Header% | |
| 11 | */ | |
| 12 | ||
| 13 | #include <stdio.h> | |
| 14 | #include <string.h> | |
| 15 | #if HAVE_UNISTD_H | |
| 16 | #include <unistd.h> | |
| 17 | #endif | |
| 18 | #include <fcntl.h> | |
| 19 | #include <time.h> | |
| 20 | #if HAVE_SYS_STAT_H | |
| 21 | #include <sys/stat.h> | |
| 22 | #endif | |
| 23 | #if HAVE_SYS_TYPES_H | |
| 24 | #include <sys/types.h> | |
| 25 | #endif | |
| 26 | ||
| 27 | #include "ext2_fs.h" | |
| 28 | #include "ext2fs.h" | |
| 29 | ||
| 4a568505 TT |
30 | /* |
| 31 | * This function reserves the superblock and block group descriptors | |
| 32 | * for a given block group. It currently returns the number of free | |
| 33 | * blocks assuming that inode table and allocation bitmaps will be in | |
| 34 | * the group. This is not necessarily the case when the flex_bg | |
| 35 | * feature is enabled, so callers should take care! It was only | |
| 36 | * really intended for use by mke2fs, and even there it's not that | |
| 37 | * useful. In the future, when we redo this function for 64-bit block | |
| 38 | * numbers, we should probably return the number of blocks used by the | |
| 39 | * super block and group descriptors instead. | |
| 40 | * | |
| 41 | * See also the comment for ext2fs_super_and_bgd_loc() | |
| 42 | */ | |
| efc6f628 | 43 | int ext2fs_reserve_super_and_bgd(ext2_filsys fs, |
| ef344e13 TT |
44 | dgrp_t group, |
| 45 | ext2fs_block_bitmap bmap) | |
| 46 | { | |
| 47 | blk_t super_blk, old_desc_blk, new_desc_blk; | |
| 48 | int j, old_desc_blocks, num_blocks; | |
| 49 | ||
| efc6f628 | 50 | num_blocks = ext2fs_super_and_bgd_loc(fs, group, &super_blk, |
| ef344e13 TT |
51 | &old_desc_blk, &new_desc_blk, 0); |
| 52 | ||
| 53 | if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) | |
| 54 | old_desc_blocks = fs->super->s_first_meta_bg; | |
| 55 | else | |
| efc6f628 | 56 | old_desc_blocks = |
| d323f8fb | 57 | fs->desc_blocks + fs->super->s_reserved_gdt_blocks; |
| ef344e13 TT |
58 | |
| 59 | if (super_blk || (group == 0)) | |
| 60 | ext2fs_mark_block_bitmap(bmap, super_blk); | |
| 61 | ||
| 62 | if (old_desc_blk) { | |
| 5711ed29 TT |
63 | if (fs->super->s_reserved_gdt_blocks && fs->block_map == bmap) |
| 64 | fs->group_desc[group].bg_flags &= ~EXT2_BG_BLOCK_UNINIT; | |
| ef344e13 | 65 | for (j=0; j < old_desc_blocks; j++) |
| 009c02ba TT |
66 | if (old_desc_blk + j < fs->super->s_blocks_count) |
| 67 | ext2fs_mark_block_bitmap(bmap, | |
| 68 | old_desc_blk + j); | |
| ef344e13 TT |
69 | } |
| 70 | if (new_desc_blk) | |
| 71 | ext2fs_mark_block_bitmap(bmap, new_desc_blk); | |
| 72 | ||
| 73 | return num_blocks; | |
| 74 | } |