bcache: Send a uevent with a cached device's UUID

Signed-off-by: Gabriel de Perthuis <g2p.code@gmail.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 8c73f0c7f28a..a104dad2c7fa 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -825,6 +825,11 @@ static void calc_cached_dev_sectors(struct cache_set *c)
 void bch_cached_dev_run(struct cached_dev *dc)
 {
         struct bcache_device *d = &dc->disk;
+        char *env[] = {
+                "DRIVER=bcache",
+                kasprintf(GFP_KERNEL, "CACHED_UUID=%pU", dc->sb.uuid),
+                NULL
+        };
 
         if (atomic_xchg(&dc->running, 1))
                 return;
@@ -841,10 +846,11 @@ void bch_cached_dev_run(struct cached_dev *dc)
 
         add_disk(d->disk);
         bd_link_disk_holder(dc->bdev, dc->disk.disk);
-#if 0
-        char *env[] = { "SYMLINK=label" , NULL };
+        /* won't show up in the uevent file, use udevadm monitor -e instead
+         * only class / kset properties are persistent */
         kobject_uevent_env(&disk_to_dev(d->disk)->kobj, KOBJ_CHANGE, env);
-#endif
+        kfree(env[1]);
+
         if (sysfs_create_link(&d->kobj, &disk_to_dev(d->disk)->kobj, "dev") ||
             sysfs_create_link(&disk_to_dev(d->disk)->kobj, &d->kobj, "bcache"))
                 pr_debug("error creating sysfs link");