From: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Date: Mon, 7 Jul 2014 01:56:51 +0000 (+0800)
Subject: btrfs-progs: add mount status check for btrfs-image
X-Git-Tag: upstream/4.16.1~2737
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f0884b5dc30c134bcb87a43342ca26d0773295ee;p=platform%2Fupstream%2Fbtrfs-progs.git

btrfs-progs: add mount status check for btrfs-image

When btrfs-image run on a mounted filesystem,
the undergoing fs operations may change what you have imaged a while ago.
In this case, give a warning to remind the user that he may not
get a consistent image he wants.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
[tweaked the message]
Signed-off-by: David Sterba <dsterba@suse.cz>
---

diff --git a/btrfs-image.c b/btrfs-image.c
index 985aa26..cb17f16 100644
--- a/btrfs-image.c
+++ b/btrfs-image.c
@@ -2570,12 +2570,22 @@ int main(int argc, char *argv[])
 			num_threads = 1;
 	}
 
-	if (create)
+	if (create) {
+		ret = check_mounted(source);
+		if (ret < 0) {
+			fprintf(stderr, "Could not check mount status: %s\n",
+				strerror(-ret));
+			exit(1);
+		} else if (ret)
+			fprintf(stderr,
+		"WARNING: The device is mounted. Make sure the filesystem is quiescent.\n");
+
 		ret = create_metadump(source, out, num_threads,
 				      compress_level, sanitize, walk_trees);
-	else
+	} else {
 		ret = restore_metadump(source, out, old_restore, 1,
 				       multi_devices);
+	}
 	if (ret) {
 		printk("%s failed (%s)\n", (create) ? "create" : "restore",
 		       strerror(errno));