qemu-io: Add command line switch for cache mode

To be used as in 'qemu-io -t writeback test.img'

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 9 insertions, 1 deletions

diff --git a/qemu-io.c b/qemu-io.c
index e6fcd7719e..3095a22be3 100644
--- a/qemu-io.c
+++ b/qemu-io.c
@@ -1784,6 +1784,7 @@ static void usage(const char *name)
 "  -g, --growable       allow file to grow (only applies to protocols)\n"
 "  -m, --misalign       misalign allocations for O_DIRECT\n"
 "  -k, --native-aio     use kernel AIO implementation (on Linux only)\n"
+"  -t, --cache=MODE     use the given cache mode for the image\n"
 "  -T, --trace FILE     enable trace events listed in the given file\n"
 "  -h, --help           display this help and exit\n"
 "  -V, --version        output version information and exit\n"
@@ -1796,7 +1797,7 @@ int main(int argc, char **argv)
 {
     int readonly = 0;
     int growable = 0;
-    const char *sopt = "hVc:rsnmgkT:";
+    const char *sopt = "hVc:rsnmgkt:T:";
     const struct option lopt[] = {
         { "help", 0, NULL, 'h' },
         { "version", 0, NULL, 'V' },
@@ -1808,6 +1809,7 @@ int main(int argc, char **argv)
         { "misalign", 0, NULL, 'm' },
         { "growable", 0, NULL, 'g' },
         { "native-aio", 0, NULL, 'k' },
+        { "cache", 1, NULL, 't' },
         { "trace", 1, NULL, 'T' },
         { NULL, 0, NULL, 0 }
     };
@@ -1840,6 +1842,12 @@ int main(int argc, char **argv)
         case 'k':
             flags |= BDRV_O_NATIVE_AIO;
             break;
+        case 't':
+            if (bdrv_parse_cache_flags(optarg, &flags) < 0) {
+                error_report("Invalid cache option: %s", optarg);
+                exit(1);
+            }
+            break;
         case 'T':
             if (!trace_backend_init(optarg, NULL)) {
                 exit(1); /* error message will have been printed */