UBI: block: Add support for the UBI_VOLUME_UPDATED notification

Static volumes can change its 'used_bytes' when they get updated,
and so the block interface must listen to the UBI_VOLUME_UPDATED
notification to resize the block device accordingly.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@vger.kernel.org # v3.15+

diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
index 5817844..8876c7d 100644 (file)
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -524,8 +524,12 @@ static int ubiblock_resize(struct ubi_volume_info *vi)
        }
 
        mutex_lock(&dev->dev_mutex);
-       set_capacity(dev->gd, disk_capacity);
-       ubi_msg("%s resized to %lld bytes", dev->gd->disk_name, vi->used_bytes);
+
+       if (get_capacity(dev->gd) != disk_capacity) {
+               set_capacity(dev->gd, disk_capacity);
+               ubi_msg("%s resized to %lld bytes", dev->gd->disk_name,
+                       vi->used_bytes);
+       }
        mutex_unlock(&dev->dev_mutex);
        mutex_unlock(&devices_mutex);
        return 0;
@@ -549,6 +553,14 @@ static int ubiblock_notify(struct notifier_block *nb,
        case UBI_VOLUME_RESIZED:
                ubiblock_resize(&nt->vi);
                break;
+       case UBI_VOLUME_UPDATED:
+               /*
+                * If the volume is static, a content update might mean the
+                * size (i.e. used_bytes) was also changed.
+                */
+               if (nt->vi.vol_type == UBI_STATIC_VOLUME)
+                       ubiblock_resize(&nt->vi);
+               break;
        default:
                break;
        }