From 3fbea4b3683a5dfa86489ef7799cbe55e8003dfa Mon Sep 17 00:00:00 2001 From: Yongqiang Yang Date: Tue, 3 Jan 2012 23:44:38 -0500 Subject: [PATCH] ext4: add a new function which allocates bitmaps and inode tables This patch adds a new function named ext4_allocates_group_table() which allocates block bitmaps, inode bitmaps and inode tables for a flex groups and is used by resize code. Signed-off-by: Yongqiang Yang Signed-off-by: "Theodore Ts'o" --- fs/ext4/resize.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 111 insertions(+) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 12eace096546..a4075de73c72 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -189,6 +189,117 @@ static void free_flex_gd(struct ext4_new_flex_group_data *flex_gd) kfree(flex_gd); } +/* + * ext4_alloc_group_tables() allocates block bitmaps, inode bitmaps + * and inode tables for a flex group. + * + * This function is used by 64bit-resize. Note that this function allocates + * group tables from the 1st group of groups contained by @flexgd, which may + * be a partial of a flex group. + * + * @sb: super block of fs to which the groups belongs + */ +static void ext4_alloc_group_tables(struct super_block *sb, + struct ext4_new_flex_group_data *flex_gd, + int flexbg_size) +{ + struct ext4_new_group_data *group_data = flex_gd->groups; + struct ext4_super_block *es = EXT4_SB(sb)->s_es; + ext4_fsblk_t start_blk; + ext4_fsblk_t last_blk; + ext4_group_t src_group; + ext4_group_t bb_index = 0; + ext4_group_t ib_index = 0; + ext4_group_t it_index = 0; + ext4_group_t group; + ext4_group_t last_group; + unsigned overhead; + + BUG_ON(flex_gd->count == 0 || group_data == NULL); + + src_group = group_data[0].group; + last_group = src_group + flex_gd->count - 1; + + BUG_ON((flexbg_size > 1) && ((src_group & ~(flexbg_size - 1)) != + (last_group & ~(flexbg_size - 1)))); +next_group: + group = group_data[0].group; + start_blk = ext4_group_first_block_no(sb, src_group); + last_blk = start_blk + group_data[src_group - group].blocks_count; + + overhead = ext4_bg_has_super(sb, src_group) ? + (1 + ext4_bg_num_gdb(sb, src_group) + + le16_to_cpu(es->s_reserved_gdt_blocks)) : 0; + + start_blk += overhead; + + BUG_ON(src_group >= group_data[0].group + flex_gd->count); + /* We collect contiguous blocks as much as possible. */ + src_group++; + for (; src_group <= last_group; src_group++) + if (!ext4_bg_has_super(sb, src_group)) + last_blk += group_data[src_group - group].blocks_count; + else + break; + + /* Allocate block bitmaps */ + for (; bb_index < flex_gd->count; bb_index++) { + if (start_blk >= last_blk) + goto next_group; + group_data[bb_index].block_bitmap = start_blk++; + ext4_get_group_no_and_offset(sb, start_blk - 1, &group, NULL); + group -= group_data[0].group; + group_data[group].free_blocks_count--; + if (flexbg_size > 1) + flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT; + } + + /* Allocate inode bitmaps */ + for (; ib_index < flex_gd->count; ib_index++) { + if (start_blk >= last_blk) + goto next_group; + group_data[ib_index].inode_bitmap = start_blk++; + ext4_get_group_no_and_offset(sb, start_blk - 1, &group, NULL); + group -= group_data[0].group; + group_data[group].free_blocks_count--; + if (flexbg_size > 1) + flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT; + } + + /* Allocate inode tables */ + for (; it_index < flex_gd->count; it_index++) { + if (start_blk + EXT4_SB(sb)->s_itb_per_group > last_blk) + goto next_group; + group_data[it_index].inode_table = start_blk; + ext4_get_group_no_and_offset(sb, start_blk, &group, NULL); + group -= group_data[0].group; + group_data[group].free_blocks_count -= + EXT4_SB(sb)->s_itb_per_group; + if (flexbg_size > 1) + flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT; + + start_blk += EXT4_SB(sb)->s_itb_per_group; + } + + if (test_opt(sb, DEBUG)) { + int i; + group = group_data[0].group; + + printk(KERN_DEBUG "EXT4-fs: adding a flex group with " + "%d groups, flexbg size is %d:\n", flex_gd->count, + flexbg_size); + + for (i = 0; i < flex_gd->count; i++) { + printk(KERN_DEBUG "adding %s group %u: %u " + "blocks (%d free)\n", + ext4_bg_has_super(sb, group + i) ? "normal" : + "no-super", group + i, + group_data[i].blocks_count, + group_data[i].free_blocks_count); + } + } +} + static struct buffer_head *bclean(handle_t *handle, struct super_block *sb, ext4_fsblk_t blk) { -- 2.39.5