qemu-img: Print available options with -o ?

This patch adds a small help text to each of the options in the block drivers
which can be displayed by using qemu-img create -f fmt -o ?

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 25 insertions, 5 deletions

diff --git a/block/qcow2.c b/block/qcow2.c
index d1611d1..c2be42e 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2981,11 +2981,31 @@ static int qcow_get_buffer(BlockDriverState *bs, uint8_t *buf,
 }
 
 static QEMUOptionParameter qcow_create_options[] = {
-    { BLOCK_OPT_SIZE,           OPT_SIZE },
-    { BLOCK_OPT_BACKING_FILE,   OPT_STRING },
-    { BLOCK_OPT_BACKING_FMT,    OPT_STRING },
-    { BLOCK_OPT_ENCRYPT,        OPT_FLAG },
-    { BLOCK_OPT_CLUSTER_SIZE,   OPT_SIZE },
+    {
+        .name = BLOCK_OPT_SIZE,
+        .type = OPT_SIZE,
+        .help = "Virtual disk size"
+    },
+    {
+        .name = BLOCK_OPT_BACKING_FILE,
+        .type = OPT_STRING,
+        .help = "File name of a base image"
+    },
+    {
+        .name = BLOCK_OPT_BACKING_FMT,
+        .type = OPT_STRING,
+        .help = "Image format of the base image"
+    },
+    {
+        .name = BLOCK_OPT_ENCRYPT,
+        .type = OPT_FLAG,
+        .help = "Encrypt the image"
+    },
+    {
+        .name = BLOCK_OPT_CLUSTER_SIZE,
+        .type = OPT_SIZE,
+        .help = "qcow2 cluster size"
+    },
     { NULL }
 };