The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From eb7054212eac8b451d727bf079eae3db8c88f9d3 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o tytso@mit.edu Date: Thu, 14 Apr 2022 22:39:00 -0400 Subject: [PATCH] ext4: update the cached overhead value in the superblock

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

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 48dc2c3247ad..a743b1e3b89e 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -3068,6 +3068,7 @@ int ext4_fileattr_set(struct user_namespace *mnt_userns, 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 *); diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index 992229ca2d83..ba44fa1be70a 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -1652,3 +1652,19 @@ long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 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); +} diff --git a/fs/ext4/super.c b/fs/ext4/super.c index d08820fdfdee..1847b46af808 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5618,6 +5618,8 @@ static int ext4_fill_super(struct super_block *sb, struct fs_context *fc) 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: