ext4: add support for online resizing with bigalloc
This patch adds support for online resizing on bigalloc file system by
implementing EXT4_IOC_RESIZE_FS ioctl. Old resize interfaces (add
block groups and extend last block group) are left untouched. Tests
performed with cluster sizes of 1, 2, 4 and 8 blocks (of size 4k) per
cluster. I will add these tests to xfstests.
Signed-off-by: Harshad Shirwadkar <harshads@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 7010856..d9f8b90a 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4994,8 +4994,11 @@ int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
struct ext4_group_desc *desc;
struct ext4_sb_info *sbi = EXT4_SB(sb);
struct ext4_buddy e4b;
- int err = 0, ret, blk_free_count;
- ext4_grpblk_t blocks_freed;
+ int err = 0, ret, free_clusters_count;
+ ext4_grpblk_t clusters_freed;
+ ext4_fsblk_t first_cluster = EXT4_B2C(sbi, block);
+ ext4_fsblk_t last_cluster = EXT4_B2C(sbi, block + count - 1);
+ unsigned long cluster_count = last_cluster - first_cluster + 1;
ext4_debug("Adding block(s) %llu-%llu\n", block, block + count - 1);
@@ -5007,8 +5010,8 @@ int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
* Check to see if we are freeing blocks across a group
* boundary.
*/
- if (bit + count > EXT4_BLOCKS_PER_GROUP(sb)) {
- ext4_warning(sb, "too much blocks added to group %u",
+ if (bit + cluster_count > EXT4_CLUSTERS_PER_GROUP(sb)) {
+ ext4_warning(sb, "too many blocks added to group %u",
block_group);
err = -EINVAL;
goto error_return;
@@ -5054,14 +5057,14 @@ int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
if (err)
goto error_return;
- for (i = 0, blocks_freed = 0; i < count; i++) {
+ for (i = 0, clusters_freed = 0; i < cluster_count; i++) {
BUFFER_TRACE(bitmap_bh, "clear bit");
if (!mb_test_bit(bit + i, bitmap_bh->b_data)) {
ext4_error(sb, "bit already cleared for block %llu",
(ext4_fsblk_t)(block + i));
BUFFER_TRACE(bitmap_bh, "bit already cleared");
} else {
- blocks_freed++;
+ clusters_freed++;
}
}
@@ -5075,19 +5078,20 @@ int ext4_group_add_blocks(handle_t *handle, struct super_block *sb,
* them with group lock_held
*/
ext4_lock_group(sb, block_group);
- mb_clear_bits(bitmap_bh->b_data, bit, count);
- mb_free_blocks(NULL, &e4b, bit, count);
- blk_free_count = blocks_freed + ext4_free_group_clusters(sb, desc);
- ext4_free_group_clusters_set(sb, desc, blk_free_count);
+ mb_clear_bits(bitmap_bh->b_data, bit, cluster_count);
+ mb_free_blocks(NULL, &e4b, bit, cluster_count);
+ free_clusters_count = clusters_freed +
+ ext4_free_group_clusters(sb, desc);
+ ext4_free_group_clusters_set(sb, desc, free_clusters_count);
ext4_block_bitmap_csum_set(sb, block_group, desc, bitmap_bh);
ext4_group_desc_csum_set(sb, block_group, desc);
ext4_unlock_group(sb, block_group);
percpu_counter_add(&sbi->s_freeclusters_counter,
- EXT4_NUM_B2C(sbi, blocks_freed));
+ clusters_freed);
if (sbi->s_log_groups_per_flex) {
ext4_group_t flex_group = ext4_flex_group(sbi, block_group);
- atomic64_add(EXT4_NUM_B2C(sbi, blocks_freed),
+ atomic64_add(clusters_freed,
&sbi->s_flex_groups[flex_group].free_clusters);
}