1 files changed, 14 insertions, 6 deletions

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 5de5061eb331..b2efd9083b9b 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -1099,15 +1099,18 @@ static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
         struct super_block *sb = dentry->d_sb;
         struct ext2_sb_info *sbi = EXT2_SB(sb);
         struct ext2_super_block *es = sbi->s_es;
-        unsigned long overhead;
-        int i;
         u64 fsid;
 
         if (test_opt (sb, MINIX_DF))
-                overhead = 0;
-        else {
+                sbi->s_overhead_last = 0;
+        else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
+                unsigned long i, overhead = 0;
+                smp_rmb();
+
                 /*
-                 * Compute the overhead (FS structures)
+                 * Compute the overhead (FS structures). This is constant
+                 * for a given filesystem unless the number of block groups
+                 * changes so we cache the previous value until it does.
                  */
 
                 /*
@@ -1131,17 +1134,22 @@ static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
                  */
                 overhead += (sbi->s_groups_count *
                              (2 + sbi->s_itb_per_group));
+                sbi->s_overhead_last = overhead;
+                smp_wmb();
+                sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
         }
 
         buf->f_type = EXT2_SUPER_MAGIC;
         buf->f_bsize = sb->s_blocksize;
-        buf->f_blocks = le32_to_cpu(es->s_blocks_count) - overhead;
+        buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
         buf->f_bfree = ext2_count_free_blocks(sb);
+        es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
         buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
         if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
                 buf->f_bavail = 0;
         buf->f_files = le32_to_cpu(es->s_inodes_count);
         buf->f_ffree = ext2_count_free_inodes(sb);
+        es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
         buf->f_namelen = EXT2_NAME_LEN;
         fsid = le64_to_cpup((void *)es->s_uuid) ^
                le64_to_cpup((void *)es->s_uuid + sizeof(u64));