Add missing long options and --help output.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
---
 qemu-img.c | 64 +++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 54 insertions(+), 10 deletions(-)

diff --git a/qemu-img.c b/qemu-img.c
index 0d17738fb6..8455832d34 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -4847,28 +4847,70 @@ static int img_bench(const img_cmd_t *ccmd, int argc, char **argv)
     for (;;) {
         static const struct option long_options[] = {
             {"help", no_argument, 0, 'h'},
-            {"flush-interval", required_argument, 0, OPTION_FLUSH_INTERVAL},
+            {"format", required_argument, 0, 'f'},
             {"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
+            {"cache", required_argument, 0, 't'},
+            {"count", required_argument, 0, 'c'},
+            {"depth", required_argument, 0, 'd'},
+            {"offset", required_argument, 0, 'o'},
+            {"buffer-size", required_argument, 0, 's'},
+            {"step-size", required_argument, 0, 'S'},
+            {"aio", required_argument, 0, 'i'},
+            {"native", no_argument, 0, 'n'},
+            {"write", no_argument, 0, 'w'},
             {"pattern", required_argument, 0, OPTION_PATTERN},
+            {"flush-interval", required_argument, 0, OPTION_FLUSH_INTERVAL},
             {"no-drain", no_argument, 0, OPTION_NO_DRAIN},
             {"force-share", no_argument, 0, 'U'},
             {0, 0, 0, 0}
         };
-        c = getopt_long(argc, argv, ":hc:d:f:ni:o:qs:S:t:wU", long_options,
-                        NULL);
+        c = getopt_long(argc, argv, "hc:d:f:ni:o:qs:S:t:wU",
+                        long_options, NULL);
         if (c == -1) {
             break;
         }
 
         switch (c) {
-        case ':':
-            missing_argument(argv[optind - 1]);
-            break;
-        case '?':
-            unrecognized_option(argv[optind - 1]);
-            break;
         case 'h':
-            help();
+            cmd_help(ccmd,
+"[-f FMT | --image-opts] [-t CACHE] [-c COUNT] [-d DEPTH]\n"
+"        [-o OFFSET] [-s BUFFER_SIZE] [-S STEP_SIZE] [-i AIO] [-n]\n"
+"        [-w [--pattern PATTERN] [--flush-interval INTERVAL [--no-drain]]]\n"
+,
+"  -q, --quiet\n"
+"     quiet operations\n"
+"  -f, --format FMT\n"
+"     specify FILENAME format explicitly\n"
+"  --image-opts\n"
+"     indicates that FILENAME is a complete image specification\n"
+"     instead of a file name (incompatible with --format)\n"
+"  -t, --cache CACHE\n"
+"     cache mode for FILENAME (" BDRV_DEFAULT_CACHE ")\n"
+"  -c, --count COUNT\n"
+"     number of I/O requests to perform\n"
+"  -s, --buffer-size BUFFER_SIZE\n"
+"     size of each I/O request\n"
+"  -d, --depth DEPTH\n"
+"     number of requests to perform in parallel\n"
+"  -o, --offset OFFSET\n"
+"     start first request at this OFFSET\n"
+"  -S, --step-size STEP_SIZE\n"
+"     each next request offset increment\n"
+"  -i, --aio AIO\n"
+"     async-io backend (threads, native, io_uring)\n"
+"  -n, --native\n"
+"     use native AIO backend if possible\n"
+"  -w, --write\n"
+"     perform write test (default is read)\n"
+"  --pattern PATTERN\n"
+"     write this pattern byte instead of zero\n"
+"  --flush-interval FLUSH_INTERVAL\n"
+"     issue flush after this number of requests\n"
+"  --no-drain\n"
+"     do not wait when flushing pending requests\n"
+"  -U, --force-share\n"
+"     open images in shared mode for concurrent access\n"
+);
             break;
         case 'c':
         {
@@ -4985,6 +5027,8 @@ static int img_bench(const img_cmd_t *ccmd, int argc, char **argv)
         case OPTION_IMAGE_OPTS:
             image_opts = true;
             break;
+        default:
+            tryhelp(argv[0]);
         }
     }
 
-- 
2.39.2