Some weird old filesytems have UUID-like things that we wish to expose
as UUIDs, but are smaller; add a length field so that the new
FS_IOC_(GET|SET)UUID ioctls can handle them in generic code.
Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
---
fs/super.c | 1 +
include/linux/fs.h | 1 +
2 files changed, 2 insertions(+)
diff --git a/fs/super.c b/fs/super.c
index d35e85295489..ed688d2a58a7 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -375,6 +375,7 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags,
s->s_time_gran = 1000000000;
s->s_time_min = TIME64_MIN;
s->s_time_max = TIME64_MAX;
+ s->s_uuid_len = sizeof(s->s_uuid);
s->s_shrink = shrinker_alloc(SHRINKER_NUMA_AWARE | SHRINKER_MEMCG_AWARE,
"sb-%s", type->name);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index ed5966a70495..ff41ea6c3a9c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1257,6 +1257,7 @@ struct super_block {
char s_id[32]; /* Informational name */
uuid_t s_uuid; /* UUID */
+ u8 s_uuid_len; /* Default 16, possibly smaller for weird filesystems */
unsigned int s_max_links;
--
2.43.0
