static int goal_in_my_reservation(struct ext3_reserve_window *rsv, int goal, unsigned int group, struct super_block * sb) { unsigned long group_first_block, group_last_block; group_first_block = le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block) + group * EXT3_BLOCKS_PER_GROUP(sb); group_last_block = group_first_block + EXT3_BLOCKS_PER_GROUP(sb) - 1; if ((rsv->_rsv_start > group_last_block) || (rsv->_rsv_end < group_first_block)) return 0; if ((goal >= 0) && ((goal + group_first_block < rsv->_rsv_start) || (goal + group_first_block > rsv->_rsv_end))) return 0; return 1; }
static int goal_in_my_reservation(struct ext3_reserve_window *rsv, ext3_grpblk_t grp_goal, unsigned int group, struct super_block * sb) { ext3_fsblk_t group_first_block, group_last_block; group_first_block = ext3_group_first_block_no(sb, group); group_last_block = group_first_block + (EXT3_BLOCKS_PER_GROUP(sb) - 1); if ((rsv->_rsv_start > group_last_block) || (rsv->_rsv_end < group_first_block)) return 0; if ((grp_goal >= 0) && ((grp_goal + group_first_block < rsv->_rsv_start) || (grp_goal + group_first_block > rsv->_rsv_end))) return 0; return 1; }
static int find_group_orlov(struct super_block *sb, struct inode *parent) { int parent_group = EXT3_I(parent)->i_block_group; struct ext3_sb_info *sbi = EXT3_SB(sb); struct ext3_super_block *es = sbi->s_es; int ngroups = sbi->s_groups_count; int inodes_per_group = EXT3_INODES_PER_GROUP(sb); int freei, avefreei; int freeb, avefreeb; int blocks_per_dir, ndirs; int max_debt, max_dirs, min_blocks, min_inodes; int group = -1, i; struct ext3_group_desc *desc; struct buffer_head *bh; freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter); avefreei = freei / ngroups; freeb = percpu_counter_read_positive(&sbi->s_freeblocks_counter); avefreeb = freeb / ngroups; ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter); if ((parent == sb->s_root->d_inode) || (EXT3_I(parent)->i_flags & EXT3_TOPDIR_FL)) { int best_ndir = inodes_per_group; int best_group = -1; get_random_bytes(&group, sizeof(group)); parent_group = (unsigned)group % ngroups; for (i = 0; i < ngroups; i++) { group = (parent_group + i) % ngroups; desc = ext3_get_group_desc (sb, group, &bh); if (!desc || !desc->bg_free_inodes_count) continue; if (le16_to_cpu(desc->bg_used_dirs_count) >= best_ndir) continue; if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei) continue; if (le16_to_cpu(desc->bg_free_blocks_count) < avefreeb) continue; best_group = group; best_ndir = le16_to_cpu(desc->bg_used_dirs_count); } if (best_group >= 0) return best_group; goto fallback; } blocks_per_dir = (le32_to_cpu(es->s_blocks_count) - freeb) / ndirs; max_dirs = ndirs / ngroups + inodes_per_group / 16; min_inodes = avefreei - inodes_per_group / 4; min_blocks = avefreeb - EXT3_BLOCKS_PER_GROUP(sb) / 4; max_debt = EXT3_BLOCKS_PER_GROUP(sb) / max(blocks_per_dir, BLOCK_COST); if (max_debt * INODE_COST > inodes_per_group) max_debt = inodes_per_group / INODE_COST; if (max_debt > 255) max_debt = 255; if (max_debt == 0) max_debt = 1; for (i = 0; i < ngroups; i++) { group = (parent_group + i) % ngroups; desc = ext3_get_group_desc (sb, group, &bh); if (!desc || !desc->bg_free_inodes_count) continue; if (le16_to_cpu(desc->bg_used_dirs_count) >= max_dirs) continue; if (le16_to_cpu(desc->bg_free_inodes_count) < min_inodes) continue; if (le16_to_cpu(desc->bg_free_blocks_count) < min_blocks) continue; return group; } fallback: for (i = 0; i < ngroups; i++) { group = (parent_group + i) % ngroups; desc = ext3_get_group_desc (sb, group, &bh); if (!desc || !desc->bg_free_inodes_count) continue; if (le16_to_cpu(desc->bg_free_inodes_count) >= avefreei) return group; } if (avefreei) { /* * The free-inodes counter is approximate, and for really small * filesystems the above test can fail to find any blockgroups */ avefreei = 0; goto fallback; } return -1; }
static int find_group_orlov(struct super_block *sb, struct inode *parent) { int parent_group = EXT3_I(parent)->i_block_group; struct ext3_sb_info *sbi = EXT3_SB(sb); int ngroups = sbi->s_groups_count; int inodes_per_group = EXT3_INODES_PER_GROUP(sb); unsigned int freei, avefreei; ext3_fsblk_t freeb, avefreeb; unsigned int ndirs; int max_dirs, min_inodes; ext3_grpblk_t min_blocks; int group = -1, i; struct ext3_group_desc *desc; freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter); avefreei = freei / ngroups; freeb = percpu_counter_read_positive(&sbi->s_freeblocks_counter); avefreeb = freeb / ngroups; ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter); if ((parent == sb->s_root->d_inode) || (EXT3_I(parent)->i_flags & EXT3_TOPDIR_FL)) { int best_ndir = inodes_per_group; int best_group = -1; group = prandom_u32(); parent_group = (unsigned)group % ngroups; for (i = 0; i < ngroups; i++) { group = (parent_group + i) % ngroups; desc = ext3_get_group_desc (sb, group, NULL); if (!desc || !desc->bg_free_inodes_count) continue; if (le16_to_cpu(desc->bg_used_dirs_count) >= best_ndir) continue; if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei) continue; if (le16_to_cpu(desc->bg_free_blocks_count) < avefreeb) continue; best_group = group; best_ndir = le16_to_cpu(desc->bg_used_dirs_count); } if (best_group >= 0) return best_group; goto fallback; } max_dirs = ndirs / ngroups + inodes_per_group / 16; min_inodes = avefreei - inodes_per_group / 4; min_blocks = avefreeb - EXT3_BLOCKS_PER_GROUP(sb) / 4; for (i = 0; i < ngroups; i++) { group = (parent_group + i) % ngroups; desc = ext3_get_group_desc (sb, group, NULL); if (!desc || !desc->bg_free_inodes_count) continue; if (le16_to_cpu(desc->bg_used_dirs_count) >= max_dirs) continue; if (le16_to_cpu(desc->bg_free_inodes_count) < min_inodes) continue; if (le16_to_cpu(desc->bg_free_blocks_count) < min_blocks) continue; return group; } fallback: for (i = 0; i < ngroups; i++) { group = (parent_group + i) % ngroups; desc = ext3_get_group_desc (sb, group, NULL); if (!desc || !desc->bg_free_inodes_count) continue; if (le16_to_cpu(desc->bg_free_inodes_count) >= avefreei) return group; } if (avefreei) { /* * The free-inodes counter is approximate, and for really small * filesystems the above test can fail to find any blockgroups */ avefreei = 0; goto fallback; } return -1; }