Fix using zvol as slog device

[zfs.git] / module / zfs / zvol.c

diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c
index 5d48025..7a448f1 100644 (file)
--- a/module/zfs/zvol.c
+++ b/module/zfs/zvol.c
@@ -141,6 +141,29 @@ zvol_find_by_name(const char *name)
        return NULL;
 }
 
+
+/*
+ * Given a path, return TRUE if path is a ZVOL.
+ */
+boolean_t
+zvol_is_zvol(const char *device)
+{
+       struct block_device *bdev;
+       unsigned int major;
+
+       bdev = lookup_bdev(device);
+       if (IS_ERR(bdev))
+               return (B_FALSE);
+
+       major = MAJOR(bdev->bd_dev);
+       bdput(bdev);
+
+       if (major == zvol_major)
+            return (B_TRUE);
+
+       return (B_FALSE);
+}
+
 /*
  * ZFS_IOC_CREATE callback handles dmu zvol and zap object creation.
  */