diff options
Diffstat (limited to 'qemu-img.c')
| -rw-r--r-- | qemu-img.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/qemu-img.c b/qemu-img.c index df984b11b9..d6007b2a6d 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -64,6 +64,7 @@ enum { OPTION_TARGET_IMAGE_OPTS = 263, OPTION_SIZE = 264, OPTION_PREALLOCATION = 265, + OPTION_SHRINK = 266, }; typedef enum OutputFormat { @@ -3436,6 +3437,7 @@ static int img_resize(int argc, char **argv) }, }; bool image_opts = false; + bool shrink = false; /* Remove size from argv manually so that negative numbers are not treated * as options by getopt. */ @@ -3454,6 +3456,7 @@ static int img_resize(int argc, char **argv) {"object", required_argument, 0, OPTION_OBJECT}, {"image-opts", no_argument, 0, OPTION_IMAGE_OPTS}, {"preallocation", required_argument, 0, OPTION_PREALLOCATION}, + {"shrink", no_argument, 0, OPTION_SHRINK}, {0, 0, 0, 0} }; c = getopt_long(argc, argv, ":f:hq", @@ -3496,6 +3499,9 @@ static int img_resize(int argc, char **argv) return 1; } break; + case OPTION_SHRINK: + shrink = true; + break; } } if (optind != argc - 1) { @@ -3569,6 +3575,23 @@ static int img_resize(int argc, char **argv) goto out; } + if (total_size < current_size && !shrink) { + warn_report("Shrinking an image will delete all data beyond the " + "shrunken image's end. Before performing such an " + "operation, make sure there is no important data there."); + + if (g_strcmp0(bdrv_get_format_name(blk_bs(blk)), "raw") != 0) { + error_report( + "Use the --shrink option to perform a shrink operation."); + ret = -1; + goto out; + } else { + warn_report("Using the --shrink option will suppress this message. " + "Note that future versions of qemu-img may refuse to " + "shrink images without this option."); + } + } + ret = blk_truncate(blk, total_size, prealloc, &err); if (!ret) { qprintf(quiet, "Image resized.\n"); |