From: Theodore Ts'o tytso@mit.edu
commit eb7054212eac8b451d727bf079eae3db8c88f9d3 upstream.
If we (re-)calculate the file system overhead amount and it's different from the on-disk s_overhead_clusters value, update the on-disk version since this can take potentially quite a while on bigalloc file systems.
Signed-off-by: Theodore Ts'o tytso@mit.edu Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ext4/ext4.h | 1 + fs/ext4/ioctl.c | 16 ++++++++++++++++ fs/ext4/super.c | 2 ++ 3 files changed, 19 insertions(+)
--- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -3066,6 +3066,7 @@ int ext4_fileattr_set(struct user_namesp struct dentry *dentry, struct fileattr *fa); int ext4_fileattr_get(struct dentry *dentry, struct fileattr *fa); extern void ext4_reset_inode_seed(struct inode *inode); +int ext4_update_overhead(struct super_block *sb);
/* migrate.c */ extern int ext4_ext_migrate(struct inode *); --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -1652,3 +1652,19 @@ long ext4_compat_ioctl(struct file *file return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); } #endif + +static void set_overhead(struct ext4_super_block *es, const void *arg) +{ + es->s_overhead_clusters = cpu_to_le32(*((unsigned long *) arg)); +} + +int ext4_update_overhead(struct super_block *sb) +{ + struct ext4_sb_info *sbi = EXT4_SB(sb); + + if (sb_rdonly(sb) || sbi->s_overhead == 0 || + sbi->s_overhead == le32_to_cpu(sbi->s_es->s_overhead_clusters)) + return 0; + + return ext4_update_superblocks_fn(sb, set_overhead, &sbi->s_overhead); +} --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5597,6 +5597,8 @@ static int ext4_fill_super(struct super_ ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. " "Quota mode: %s.", descr, ext4_quota_mode(sb));
+ /* Update the s_overhead_clusters if necessary */ + ext4_update_overhead(sb); return 0;
free_sbi: