diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 53 |
1 files changed, 39 insertions, 14 deletions
diff --git a/block.c b/block.c index 3031413deb..35a372df57 100644 --- a/block.c +++ b/block.c @@ -1206,7 +1206,8 @@ static int bdrv_backing_update_filename(BdrvChild *c, BlockDriverState *base, } ret = bdrv_change_backing_file(parent, filename, - base->drv ? base->drv->format_name : ""); + base->drv ? base->drv->format_name : "", + false); if (ret < 0) { error_setg_errno(errp, -ret, "Could not update backing file link"); } @@ -4680,8 +4681,8 @@ int bdrv_check(BlockDriverState *bs, * image file header * -ENOTSUP - format driver doesn't support changing the backing file */ -int bdrv_change_backing_file(BlockDriverState *bs, - const char *backing_file, const char *backing_fmt) +int bdrv_change_backing_file(BlockDriverState *bs, const char *backing_file, + const char *backing_fmt, bool warn) { BlockDriver *drv = bs->drv; int ret; @@ -4695,6 +4696,12 @@ int bdrv_change_backing_file(BlockDriverState *bs, return -EINVAL; } + if (warn && backing_file && !backing_fmt) { + warn_report("Deprecated use of backing file without explicit " + "backing format, use of this image requires " + "potentially unsafe format probing"); + } + if (drv->bdrv_change_backing_file != NULL) { ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); } else { @@ -6128,18 +6135,30 @@ void bdrv_img_create(const char *filename, const char *fmt, bs = bdrv_open(full_backing, NULL, backing_options, back_flags, &local_err); g_free(full_backing); - if (!bs && size != -1) { - /* Couldn't open BS, but we have a size, so it's nonfatal */ - warn_reportf_err(local_err, - "Could not verify backing image. " - "This may become an error in future versions.\n"); - local_err = NULL; - } else if (!bs) { - /* Couldn't open bs, do not have size */ - error_append_hint(&local_err, - "Could not open backing image to determine size.\n"); + if (!bs) { + error_append_hint(&local_err, "Could not open backing image.\n"); goto out; } else { + if (!backing_fmt) { + warn_report("Deprecated use of backing file without explicit " + "backing format (detected format of %s)", + bs->drv->format_name); + if (bs->drv != &bdrv_raw) { + /* + * A probe of raw deserves the most attention: + * leaving the backing format out of the image + * will ensure bs->probed is set (ensuring we + * don't accidentally commit into the backing + * file), and allow more spots to warn the users + * to fix their toolchain when opening this image + * later. For other images, we can safely record + * the format that we probed. + */ + backing_fmt = bs->drv->format_name; + qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, backing_fmt, + NULL); + } + } if (size == -1) { /* Opened BS, have no size */ size = bdrv_getlength(bs); @@ -6153,7 +6172,12 @@ void bdrv_img_create(const char *filename, const char *fmt, } bdrv_unref(bs); } - } /* (backing_file && !(flags & BDRV_O_NO_BACKING)) */ + /* (backing_file && !(flags & BDRV_O_NO_BACKING)) */ + } else if (backing_file && !backing_fmt) { + warn_report("Deprecated use of unopened backing file without " + "explicit backing format, use of this image requires " + "potentially unsafe format probing"); + } if (size == -1) { error_setg(errp, "Image creation needs a size parameter"); @@ -6164,6 +6188,7 @@ void bdrv_img_create(const char *filename, const char *fmt, printf("Formatting '%s', fmt=%s ", filename, fmt); qemu_opts_print(opts, " "); puts(""); + fflush(stdout); } ret = bdrv_create(drv, filename, opts, &local_err); |