Signed-off-by: Wenchao Xia <xiaw...@linux.vnet.ibm.com> --- qemu-nbd.c | 8 +++++++- qemu-nbd.texi | 8 +++++++- 2 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/qemu-nbd.c b/qemu-nbd.c index e450d04..8cb4bf1 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -80,7 +80,13 @@ static void usage(const char *name) "\n" "Block device options:\n" " -r, --read-only export read-only\n" -" -s, --snapshot use snapshot file\n" +" -s, --snapshot use FILE as an external snapshot, create a temporary\n" +" file with backing_file=FILE, redirect the write to\n" +" the temporary one\n" +" -l, --snapshot-load=PARAM\n" +" load an internal snapshot inside FILE and export it\n" +" as an read-only device, PARAM format is\n" +" 'id=[ID],name=[NAME]'\n" " -n, --nocache disable host cache\n" " --cache=MODE set cache mode (none, writeback, ...)\n" #ifdef CONFIG_LINUX_AIO diff --git a/qemu-nbd.texi b/qemu-nbd.texi index 6055ec6..69e9e9a 100644 --- a/qemu-nbd.texi +++ b/qemu-nbd.texi @@ -27,7 +27,13 @@ Export QEMU disk image using NBD protocol. @item -P, --partition=@var{num} only expose partition @var{num} @item -s, --snapshot - use snapshot file + use @var{filename} as an external snapshot, create a temporary + file with backing_file=@var{filename}, redirect the write to + the temporary one +@item -l, --snapshot-load=@var{param} + load an internal snapshot inside @var{filename} and export it + as an read-only device, @var{param} format is + 'id=[ID],name=[NAME]' @item -n, --nocache @itemx --cache=@var{cache} set cache mode to be used with the file. See the documentation of -- 1.7.1