ext4: notify sysfs on errors_count value change
After s_error_count is incremented, signal the change in the
corresponding sysfs attribute via sysfs_notify. This allows userspace to
poll() on changes to /sys/fs/ext4/*/errors_count.
[ Moved call of ext4_notify_error_sysfs() to flush_stashed_error_work()
to avoid BUG's caused by calling sysfs_notify trying to sleep after
being called from an invalid context. -- TYT ]
Signed-off-by: Jonathan Davies <jonathan.davies@nutanix.com>
Link: https://lore.kernel.org/r/20210611140209.28903-1-jonathan.davies@nutanix.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 8ff4ae3..3c51e24 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3624,6 +3624,7 @@ extern const struct inode_operations ext4_symlink_inode_operations;
extern const struct inode_operations ext4_fast_symlink_inode_operations;
/* sysfs.c */
+extern void ext4_notify_error_sysfs(struct ext4_sb_info *sbi);
extern int ext4_register_sysfs(struct super_block *sb);
extern void ext4_unregister_sysfs(struct super_block *sb);
extern int __init ext4_init_sysfs(void);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 9e0fb79..2034463 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -718,6 +718,7 @@ static void flush_stashed_error_work(struct work_struct *work)
goto write_directly;
}
jbd2_journal_stop(handle);
+ ext4_notify_error_sysfs(sbi);
return;
}
write_directly:
@@ -726,6 +727,7 @@ static void flush_stashed_error_work(struct work_struct *work)
* out and hope for the best.
*/
ext4_commit_super(sbi->s_sb);
+ ext4_notify_error_sysfs(sbi);
}
#define ext4_error_ratelimit(sb) \
diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 55fcab6..2314f74 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -506,6 +506,11 @@ static struct kobj_type ext4_feat_ktype = {
.release = (void (*)(struct kobject *))kfree,
};
+void ext4_notify_error_sysfs(struct ext4_sb_info *sbi)
+{
+ sysfs_notify(&sbi->s_kobj, NULL, "errors_count");
+}
+
static struct kobject *ext4_root;
static struct kobject *ext4_feat;