ext4: add interface to advertise ext4 features in sysfs

User-space should have the opportunity to check what features doest ext4
support in each particular copy. This adds easy interface by creating new
"features" directory in sys/fs/ext4/. In that directory files
advertising feature names can be created.

Add lazy_itable_init to the feature list.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 0fe078d368d0..4c5fe37b237d 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1574,6 +1574,11 @@ struct ext4_li_request {
         unsigned long           lr_timeout;
 };
 
+struct ext4_features {
+        struct kobject f_kobj;
+        struct completion f_kobj_unregister;
+};
+
 /*
  * Function prototypes
  */