Revert "qemu-img: Check post-truncation size"

This reverts commit 5279b30392da7a3248b320c75f20c61e3a95863c.

We no longer need this check because exact=true forces the block driver
to give the image the exact size requested by the user.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190918095144.955-9-mreitz@redhat.com
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

qemu-img.c

@@ -3656,7 +3656,7 @@ static int img_resize(int argc, char **argv)
     Error *err = NULL;
     int c, ret, relative;
     const char *filename, *fmt, *size;
-    int64_t n, total_size, current_size, new_size;
+    int64_t n, total_size, current_size;
     bool quiet = false;
     BlockBackend *blk = NULL;
     PreallocMode prealloc = PREALLOC_MODE_OFF;
@@ -3837,42 +3837,11 @@ static int img_resize(int argc, char **argv)
      * success when the image has not actually been resized.
      */
     ret = blk_truncate(blk, total_size, true, prealloc, &err);
-    if (ret < 0) {
+    if (!ret) {
+        qprintf(quiet, "Image resized.\n");
+    } else {
         error_report_err(err);
-        goto out;
-    }
-
-    new_size = blk_getlength(blk);
-    if (new_size < 0) {
-        error_report("Failed to verify truncated image length: %s",
-                     strerror(-new_size));
-        ret = -1;
-        goto out;
     }
-
-    /* Some block drivers implement a truncation method, but only so
-     * the user can cause qemu to refresh the image's size from disk.
-     * The idea is that the user resizes the image outside of qemu and
-     * then invokes block_resize to inform qemu about it.
-     * (This includes iscsi and file-posix for device files.)
-     * Of course, that is not the behavior someone invoking
-     * qemu-img resize would find useful, so we catch that behavior
-     * here and tell the user. */
-    if (new_size != total_size && new_size == current_size) {
-        error_report("Image was not resized; resizing may not be supported "
-                     "for this image");
-        ret = -1;
-        goto out;
-    }
-
-    if (new_size != total_size) {
-        warn_report("Image should have been resized to %" PRIi64
-                    " bytes, but was resized to %" PRIi64 " bytes",
-                    total_size, new_size);
-    }
-
-    qprintf(quiet, "Image resized.\n");
-
 out:
     blk_unref(blk);
     if (ret) {