ext2_initialize_sb ext2_print_super inode_ratio set_field

bool ext2_initialize_sb ( PEXT2_FILESYS  Ext2Sys ) Definition at line 74 of file Super.c. Referenced by Ext2Format(). { int frags_per_block = 0; ULONG overhead = 0; int rem = 0; ULONG i = 0; ULONG group_block = 0; ULONG numblocks = 0; PEXT2_SUPER_BLOCK pExt2Sb = Ext2Sys->ext2_sb; LARGE_INTEGER SysTime; NtQuerySystemTime(&SysTime); Ext2Sys->blocksize = EXT2_BLOCK_SIZE(pExt2Sb); Ext2Sys->fragsize = EXT2_FRAG_SIZE(pExt2Sb); frags_per_block = Ext2Sys->blocksize / Ext2Sys->fragsize; pExt2Sb->s_magic = EXT2_SUPER_MAGIC; pExt2Sb->s_state = EXT2_VALID_FS; pExt2Sb->s_first_data_block = (pExt2Sb->s_log_block_size) ? 0 : 1; pExt2Sb->s_max_mnt_count = EXT2_DFL_MAX_MNT_COUNT; pExt2Sb->s_errors = EXT2_ERRORS_DEFAULT; pExt2Sb->s_checkinterval = EXT2_DFL_CHECKINTERVAL; if (!pExt2Sb->s_rev_level) pExt2Sb->s_rev_level = EXT2_GOOD_OLD_REV; if (pExt2Sb->s_rev_level >= EXT2_DYNAMIC_REV) { set_field(s_first_ino, EXT2_GOOD_OLD_FIRST_INO); set_field(s_inode_size, EXT2_GOOD_OLD_INODE_SIZE); } RtlTimeToSecondsSince1970(&SysTime, &pExt2Sb->s_wtime); pExt2Sb->s_lastcheck = pExt2Sb->s_mtime = pExt2Sb->s_wtime; if (!pExt2Sb->s_blocks_per_group) pExt2Sb->s_blocks_per_group = Ext2Sys->blocksize * 8; pExt2Sb->s_frags_per_group = pExt2Sb->s_blocks_per_group * frags_per_block; pExt2Sb->s_creator_os = EXT2_OS_WINNT; if (pExt2Sb->s_r_blocks_count >= pExt2Sb->s_blocks_count) { goto cleanup; } /* * If we're creating an external journal device, we don't need * to bother with the rest. */ if (pExt2Sb->s_feature_incompat & EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) { Ext2Sys->group_desc_count = 0; // ext2fs_mark_super_dirty(fs); return true; } retry: Ext2Sys->group_desc_count = (pExt2Sb->s_blocks_count - pExt2Sb->s_first_data_block + EXT2_BLOCKS_PER_GROUP(pExt2Sb) - 1) / EXT2_BLOCKS_PER_GROUP(pExt2Sb); if (Ext2Sys->group_desc_count == 0) return false; Ext2Sys->desc_blocks = (Ext2Sys->group_desc_count + EXT2_DESC_PER_BLOCK(pExt2Sb) - 1) / EXT2_DESC_PER_BLOCK(pExt2Sb); if (!pExt2Sb->s_inodes_count) pExt2Sb->s_inodes_count = pExt2Sb->s_blocks_count / ( inode_ratio /Ext2Sys->blocksize); /* * Make sure we have at least EXT2_FIRST_INO + 1 inodes, so * that we have enough inodes for the filesystem(!) */ if (pExt2Sb->s_inodes_count < EXT2_FIRST_INODE(pExt2Sb)+1) pExt2Sb->s_inodes_count = EXT2_FIRST_INODE(pExt2Sb)+1; /* * There should be at least as many inodes as the user * requested. Figure out how many inodes per group that * should be. But make sure that we don't allocate more than * one bitmap's worth of inodes */ pExt2Sb->s_inodes_per_group = (pExt2Sb->s_inodes_count + Ext2Sys->group_desc_count - 1) /Ext2Sys->group_desc_count; if (pExt2Sb->s_inodes_per_group > (ULONG)(Ext2Sys->blocksize*8)) pExt2Sb->s_inodes_per_group = Ext2Sys->blocksize*8; /* * Make sure the number of inodes per group completely fills * the inode table blocks in the descriptor. If not, add some * additional inodes/group. Waste not, want not... */ Ext2Sys->inode_blocks_per_group = (((pExt2Sb->s_inodes_per_group * EXT2_INODE_SIZE(pExt2Sb)) + EXT2_BLOCK_SIZE(pExt2Sb) - 1) / EXT2_BLOCK_SIZE(pExt2Sb)); pExt2Sb->s_inodes_per_group = ((Ext2Sys->inode_blocks_per_group * EXT2_BLOCK_SIZE(pExt2Sb)) / EXT2_INODE_SIZE(pExt2Sb)); /* * Finally, make sure the number of inodes per group is a * multiple of 8. This is needed to simplify the bitmap * splicing code. */ pExt2Sb->s_inodes_per_group &= ~7; Ext2Sys->inode_blocks_per_group = (((pExt2Sb->s_inodes_per_group * EXT2_INODE_SIZE(pExt2Sb)) + EXT2_BLOCK_SIZE(pExt2Sb) - 1) / EXT2_BLOCK_SIZE(pExt2Sb)); /* * adjust inode count to reflect the adjusted inodes_per_group */ pExt2Sb->s_inodes_count = pExt2Sb->s_inodes_per_group * Ext2Sys->group_desc_count; pExt2Sb->s_free_inodes_count = pExt2Sb->s_inodes_count; /* * Overhead is the number of bookkeeping blocks per group. It * includes the superblock backup, the group descriptor * backups, the inode bitmap, the block bitmap, and the inode * table. * * XXX Not all block groups need the descriptor blocks, but * being clever is tricky... */ overhead = (int) (3 + Ext2Sys->desc_blocks + Ext2Sys->inode_blocks_per_group); /* * See if the last group is big enough to support the * necessary data structures. If not, we need to get rid of * it. */ rem = (int) ((pExt2Sb->s_blocks_count - pExt2Sb->s_first_data_block) % pExt2Sb->s_blocks_per_group); if ((Ext2Sys->group_desc_count == 1) && rem && (rem < overhead)) return false; if (rem && (rem < overhead+50)) { pExt2Sb->s_blocks_count -= rem; goto retry; } /* * At this point we know how big the filesystem will be. So we can do * any and all allocations that depend on the block count. */ // Allocate block bitmap if(!ext2_allocate_block_bitmap(Ext2Sys)) { goto cleanup; } // Allocate inode bitmap if(!ext2_allocate_inode_bitmap(Ext2Sys)) { goto cleanup; } // Allocate gourp desc if(!ext2_allocate_group_desc(Ext2Sys)) { goto cleanup; } /* * Reserve the superblock and group descriptors for each * group, and fill in the correct group statistics for group. * Note that although the block bitmap, inode bitmap, and * inode table have not been allocated (and in fact won't be * by this routine), they are accounted for nevertheless. */ group_block = pExt2Sb->s_first_data_block; numblocks = 0; pExt2Sb->s_free_blocks_count = 0; for (i = 0; i < Ext2Sys->group_desc_count; i++) { if (i == Ext2Sys->group_desc_count-1) { numblocks = (pExt2Sb->s_blocks_count - pExt2Sb->s_first_data_block) % pExt2Sb->s_blocks_per_group; if (!numblocks) numblocks = pExt2Sb->s_blocks_per_group; } else { numblocks = pExt2Sb->s_blocks_per_group; } if (ext2_bg_has_super(pExt2Sb, i)) { ULONG j; for (j=0; j < Ext2Sys->desc_blocks+1; j++) ext2_mark_bitmap(Ext2Sys->block_map, group_block + j); numblocks -= 1 + Ext2Sys->desc_blocks; } numblocks -= 2 + Ext2Sys->inode_blocks_per_group; pExt2Sb->s_free_blocks_count += numblocks; Ext2Sys->group_desc[i].bg_free_blocks_count = (__u16)numblocks; Ext2Sys->group_desc[i].bg_free_inodes_count = (__u16)pExt2Sb->s_inodes_per_group; Ext2Sys->group_desc[i].bg_used_dirs_count = 0; group_block += pExt2Sb->s_blocks_per_group; } return true; cleanup: ext2_free_group_desc(Ext2Sys); ext2_free_block_bitmap(Ext2Sys); ext2_free_inode_bitmap(Ext2Sys); return false; }