ext4: Use EXT4_GROUP_INFO_NEED_INIT_BIT during resize

(cherry picked from commit 920313a726e04fef0f2c0bcb04ad8229c0e700d8)

The new groups added during resize are flagged as
need_init group. Make sure we properly initialize these
groups. When we have block size < page size and we are adding
new groups the page may still be marked uptodate even though
we haven't initialized the group. While forcing the init
of buddy cache we need to make sure other groups part of the
same page of buddy cache is not using the cache.
group_info->alloc_sem is added to ensure the same.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 8 insertions, 34 deletions

diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index e2bc37381364..fcb911e2e7a4 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -747,6 +747,7 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
 	struct inode *inode = NULL;
 	handle_t *handle;
 	int gdb_off, gdb_num;
+	int num_grp_locked = 0;
 	int err, err2;
 
 	gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
@@ -787,6 +788,7 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
 		}
 	}
 
+
 	if ((err = verify_group_input(sb, input)))
 		goto exit_put;
 
@@ -855,6 +857,7 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
          * using the new disk blocks.
          */
 
+	num_grp_locked = ext4_mb_get_buddy_cache_lock(sb, input->group);
 	/* Update group descriptor block for new group */
 	gdp = (struct ext4_group_desc *)((char *)primary->b_data +
 					 gdb_off * EXT4_DESC_SIZE(sb));
@@ -871,9 +874,11 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
 	 * descriptor
 	 */
 	if (test_opt(sb, MBALLOC)) {
-		err = ext4_mb_add_more_groupinfo(sb, input->group, gdp);
-		if (err)
+		err = ext4_mb_add_groupinfo(sb, input->group, gdp);
+		if (err) {
+			ext4_mb_put_buddy_cache_lock(sb, input->group, num_grp_locked);
 			goto exit_journal;
+		}
 	}
 	/*
 	 * Make the new blocks and inodes valid next.  We do this before
@@ -915,6 +920,7 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
 
 	/* Update the global fs size fields */
 	sbi->s_groups_count++;
+	ext4_mb_put_buddy_cache_lock(sb, input->group, num_grp_locked);
 
 	ext4_journal_dirty_metadata(handle, primary);
 
@@ -1082,38 +1088,6 @@ int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
 	if ((err = ext4_journal_stop(handle)))
 		goto exit_put;
 
-	/*
-	 * Mark mballoc pages as not up to date so that they will be updated
-	 * next time they are loaded by ext4_mb_load_buddy.
-	 */
-	if (test_opt(sb, MBALLOC)) {
-		struct ext4_sb_info *sbi = EXT4_SB(sb);
-		struct inode *inode = sbi->s_buddy_cache;
-		int blocks_per_page;
-		int block;
-		int pnum;
-		struct page *page;
-
-		/* Set buddy page as not up to date */
-		blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize;
-		block = group * 2;
-		pnum = block / blocks_per_page;
-		page = find_get_page(inode->i_mapping, pnum);
-		if (page != NULL) {
-			ClearPageUptodate(page);
-			page_cache_release(page);
-		}
-
-		/* Set bitmap page as not up to date */
-		block++;
-		pnum = block / blocks_per_page;
-		page = find_get_page(inode->i_mapping, pnum);
-		if (page != NULL) {
-			ClearPageUptodate(page);
-			page_cache_release(page);
-		}
-	}
-
 	if (test_opt(sb, DEBUG))
 		printk(KERN_DEBUG "EXT4-fs: extended group to %llu blocks\n",
 		       ext4_blocks_count(es));