On Mon, 2021-09-13 at 08:17 -0500, Eric Blake wrote:
> Although we have long supported 'qemu-img convert -o
> backing_file=foo,backing_fmt=bar', the fact that we have a shortcut -B
> for backing_file but none for backing_fmt has made it more likely that
> users accidentally run into:
>
> qemu-img: warning: Deprecated use of backing file without explicit backing
> format
>
> when using -B instead of -o. For similarity with other qemu-img
> commands, such as create and compare, add '-F $fmt' as the shorthand
> for '-o backing_fmt=$fmt'. Update iotest 122 for coverage of both
> spellings.
>
> Signed-off-by: Eric Blake <ebl...@redhat.com>
> ---
>
> This stemmed from an IRC conversation; I'd add a Reported-by: line if
> I can figure out how to credit more than just the nick bparker_.
>
> docs/tools/qemu-img.rst | 4 ++--
> qemu-img.c | 10 +++++++---
> qemu-img-cmds.hx | 2 +-
> tests/qemu-iotests/122 | 2 +-
> 4 files changed, 11 insertions(+), 7 deletions(-)
>
> diff --git a/docs/tools/qemu-img.rst b/docs/tools/qemu-img.rst
> index b7d602a28804..e02880c1c5dc 100644
> --- a/docs/tools/qemu-img.rst
> +++ b/docs/tools/qemu-img.rst
> @@ -414,7 +414,7 @@ Command description:
> 4
> Error on reading data
>
> -.. option:: convert [--object OBJECTDEF] [--image-opts]
> [--target-image-opts] [--target-is-zero] [--bitmaps [--skip-broken-bitmaps]]
> [-U] [-C] [-c] [-p] [-q] [-n] [-f FMT] [-t CACHE] [-T SRC_CACHE] [-O
> OUTPUT_FMT] [-B BACKING_FILE] [-o OPTIONS] [-l SNAPSHOT_PARAM] [-S
> SPARSE_SIZE] [-r RATE_LIMIT] [-m NUM_COROUTINES] [-W] FILENAME [FILENAME2
> [...]] OUTPUT_FILENAME
> +.. option:: convert [--object OBJECTDEF] [--image-opts]
> [--target-image-opts] [--target-is-zero] [--bitmaps [--skip-broken-bitmaps]]
> [-U] [-C] [-c] [-p] [-q] [-n] [-f FMT] [-t CACHE] [-T SRC_CACHE] [-O
> OUTPUT_FMT] [-B BACKING_FILE [-F backing_fmt]] [-o OPTIONS] [-l
> SNAPSHOT_PARAM] [-S SPARSE_SIZE] [-r RATE_LIMIT] [-m NUM_COROUTINES] [-W]
> FILENAME [FILENAME2 [...]] OUTPUT_FILENAME
>
> Convert the disk image *FILENAME* or a snapshot *SNAPSHOT_PARAM*
> to disk image *OUTPUT_FILENAME* using format *OUTPUT_FMT*. It can
> @@ -438,7 +438,7 @@ Command description:
> You can use the *BACKING_FILE* option to force the output image to be
> created as a copy on write image of the specified base image; the
> *BACKING_FILE* should have the same content as the input's base image,
> - however the path, image format, etc may differ.
> + however the path, image format (as given by *BACKING_FMT*), etc may differ.
>
> If a relative path name is given, the backing file is looked up relative to
> the directory containing *OUTPUT_FILENAME*.
> diff --git a/qemu-img.c b/qemu-img.c
> index d77f3e76a9b6..290368da7d6d 100644
> --- a/qemu-img.c
> +++ b/qemu-img.c
> @@ -2183,7 +2183,8 @@ static int img_convert(int argc, char **argv)
> int c, bs_i, flags, src_flags = BDRV_O_NO_SHARE;
> const char *fmt = NULL, *out_fmt = NULL, *cache = "unsafe",
> *src_cache = BDRV_DEFAULT_CACHE, *out_baseimg = NULL,
> - *out_filename, *out_baseimg_param, *snapshot_name = NULL;
> + *out_filename, *out_baseimg_param, *snapshot_name = NULL,
> + *backing_fmt = NULL;
> BlockDriver *drv = NULL, *proto_drv = NULL;
> BlockDriverInfo bdi;
> BlockDriverState *out_bs;
> @@ -2223,7 +2224,7 @@ static int img_convert(int argc, char **argv)
> {"skip-broken-bitmaps", no_argument, 0, OPTION_SKIP_BROKEN},
> {0, 0, 0, 0}
> };
> - c = getopt_long(argc, argv, ":hf:O:B:Cco:l:S:pt:T:qnm:WUr:",
> + c = getopt_long(argc, argv, ":hf:O:B:CcF:o:l:S:pt:T:qnm:WUr:",
> long_options, NULL);
> if (c == -1) {
> break;
> @@ -2253,6 +2254,9 @@ static int img_convert(int argc, char **argv)
> case 'c':
> s.compressed = true;
> break;
> + case 'F':
> + backing_fmt = optarg;
> + break;
> case 'o':
> if (accumulate_options(&options, optarg) < 0) {
> goto fail_getopt;
> @@ -2521,7 +2525,7 @@ static int img_convert(int argc, char **argv)
>
> qemu_opt_set_number(opts, BLOCK_OPT_SIZE,
> s.total_sectors * BDRV_SECTOR_SIZE,
> &error_abort);
> - ret = add_old_style_options(out_fmt, opts, out_baseimg, NULL);
> + ret = add_old_style_options(out_fmt, opts, out_baseimg, backing_fmt);
> if (ret < 0) {
> goto out;
> }
> diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx
> index b3620f29e50c..4c4d94ab2267 100644
> --- a/qemu-img-cmds.hx
> +++ b/qemu-img-cmds.hx
> @@ -46,7 +46,7 @@ SRST
> ERST
>
> DEF("convert", img_convert,
> - "convert [--object objectdef] [--image-opts] [--target-image-opts]
> [--target-is-zero] [--bitmaps] [-U] [-C] [-c] [-p] [-q] [-n] [-f fmt] [-t
> cache] [-T src_cache] [-O output_fmt] [-B backing_file] [-o options] [-l
> snapshot_param] [-S sparse_size] [-r rate_limit] [-m num_coroutines] [-W]
> [--salvage] filename [filename2 [...]] output_filename")
> + "convert [--object objectdef] [--image-opts] [--target-image-opts]
> [--target-is-zero] [--bitmaps] [-U] [-C] [-c] [-p] [-q] [-n] [-f fmt] [-t
> cache] [-T src_cache] [-O output_fmt] [-B backing_file [-F backing_fmt]] [-o
> options] [-l snapshot_param] [-S sparse_size] [-r rate_limit] [-m
> num_coroutines] [-W] [--salvage] filename [filename2 [...]] output_filename")
> SRST
> .. option:: convert [--object OBJECTDEF] [--image-opts]
> [--target-image-opts] [--target-is-zero] [--bitmaps] [-U] [-C] [-c] [-p] [-q]
> [-n] [-f FMT] [-t CACHE] [-T SRC_CACHE] [-O OUTPUT_FMT] [-B BACKING_FILE] [-o
> OPTIONS] [-l SNAPSHOT_PARAM] [-S SPARSE_SIZE] [-r RATE_LIMIT] [-m
> NUM_COROUTINES] [-W] [--salvage] FILENAME [FILENAME2 [...]] OUTPUT_FILENAME
> ERST
> diff --git a/tests/qemu-iotests/122 b/tests/qemu-iotests/122
> index 5d550ed13ea3..efb260d822db 100755
> --- a/tests/qemu-iotests/122
> +++ b/tests/qemu-iotests/122
> @@ -67,7 +67,7 @@ echo
> _make_test_img -b "$TEST_IMG".base -F $IMGFMT
>
> $QEMU_IO -c "write -P 0 0 3M" "$TEST_IMG" 2>&1 | _filter_qemu_io |
> _filter_testdir
> -$QEMU_IMG convert -O $IMGFMT -B "$TEST_IMG".base -o backing_fmt=$IMGFMT \
> +$QEMU_IMG convert -O $IMGFMT -B "$TEST_IMG".base -F $IMGFMT \
> "$TEST_IMG" "$TEST_IMG".orig
> $QEMU_IO -c "read -P 0 0 3M" "$TEST_IMG".orig 2>&1 | _filter_qemu_io |
> _filter_testdir
> $QEMU_IMG convert -O $IMGFMT -c -B "$TEST_IMG".base -o backing_fmt=$IMGFMT \
I have seen that warning few times already in my scripts, so good to have this
option.
Reviewed-by: Maxim Levitsky <mlevi...@redhat.com>
Best regards,
Maxim Levitsky
