diff options
authorQu Wenruo <>2014-11-24 15:27:44 +0800
committerDavid Sterba <>2015-01-21 17:23:23 +0100
commit39568fa417ceee3133a8cadae0bd1527adf61221 (patch)
parent751fe9b91638c34eeae6e1b469b7ec6184d6107e (diff)
btrfs-progs: Doc: Add explain on 'source' and 'target' for btrfs-image.
Add explain on 'source' and 'target', which is somewhat confusing for users who want to restore dumped image. Signed-off-by: Qu Wenruo <> [reworded texts] Signed-off-by: David Sterba <>
2 files changed, 9 insertions, 1 deletions
diff --git a/Documentation/btrfs-image.txt b/Documentation/btrfs-image.txt
index b7751f90..38265171 100644
--- a/Documentation/btrfs-image.txt
+++ b/Documentation/btrfs-image.txt
@@ -13,8 +13,13 @@ DESCRIPTION
*btrfs-image* is used to create an image of a btrfs filesystem.
All data will be zeroed, but metadata and the like is preserved.
+Mainly used for debugging purposes.
+In the dump mode, source is the btrfs device/file and target is the output
+file (use '-' for stdout).
+In the restore mode (option -r), source is the dumped image and target is the btrfs device/file.
-Mainly used for debug purpose.
diff --git a/btrfs-image.c b/btrfs-image.c
index cb17f161..1341bf1f 100644
--- a/btrfs-image.c
+++ b/btrfs-image.c
@@ -2466,6 +2466,9 @@ static void print_usage(void)
fprintf(stderr, "\t-s \tsanitize file names, use once to just use garbage, use twice if you want crc collisions\n");
fprintf(stderr, "\t-w \twalk all trees instead of using extent tree, do this if your extent tree is broken\n");
fprintf(stderr, "\t-m \trestore for multiple devices\n");
+ fprintf(stderr, "\n");
+ fprintf(stderr, "\tIn the dump mode, source is the btrfs device and target is the output file (use '-' for stdout).\n");
+ fprintf(stderr, "\tIn the restore mode, source is the dumped image and target is the btrfs device/file.\n");