From 5c1ff33640293499f9b16450029c9fb4dc06543e Mon Sep 17 00:00:00 2001 From: Eric Whitney Date: Tue, 9 Apr 2013 09:27:31 -0400 Subject: [PATCH] ext4: fix free space estimate in ext4_nonda_switch() Values stored in s_freeclusters_counter and s_dirtyclusters_counter are both in cluster units. Remove the cluster to block conversion applied to s_freeclusters_counter causing an inflated estimate of free space because s_dirtyclusters_counter is not similarly converted. Rename free_blocks and dirty_blocks to better reflect the units these variables contain to avoid future confusion. This fix corrects ENOSPC failures for xfstests 127 and 231 on bigalloc file systems. Signed-off-by: Eric Whitney Signed-off-by: "Theodore Ts'o" --- fs/ext4/inode.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index a29bfc2142ef..f9b0b479ff4c 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2609,7 +2609,7 @@ static int ext4_da_writepages(struct address_space *mapping, static int ext4_nonda_switch(struct super_block *sb) { - s64 free_blocks, dirty_blocks; + s64 free_clusters, dirty_clusters; struct ext4_sb_info *sbi = EXT4_SB(sb); /* @@ -2620,17 +2620,18 @@ static int ext4_nonda_switch(struct super_block *sb) * Delalloc need an accurate free block accounting. So switch * to non delalloc when we are near to error range. */ - free_blocks = EXT4_C2B(sbi, - percpu_counter_read_positive(&sbi->s_freeclusters_counter)); - dirty_blocks = percpu_counter_read_positive(&sbi->s_dirtyclusters_counter); + free_clusters = + percpu_counter_read_positive(&sbi->s_freeclusters_counter); + dirty_clusters = + percpu_counter_read_positive(&sbi->s_dirtyclusters_counter); /* * Start pushing delalloc when 1/2 of free blocks are dirty. */ - if (dirty_blocks && (free_blocks < 2 * dirty_blocks)) + if (dirty_clusters && (free_clusters < 2 * dirty_clusters)) try_to_writeback_inodes_sb(sb, WB_REASON_FS_FREE_SPACE); - if (2 * free_blocks < 3 * dirty_blocks || - free_blocks < (dirty_blocks + EXT4_FREECLUSTERS_WATERMARK)) { + if (2 * free_clusters < 3 * dirty_clusters || + free_clusters < (dirty_clusters + EXT4_FREECLUSTERS_WATERMARK)) { /* * free block count is less than 150% of dirty blocks * or free blocks is less than watermark