Re: [Libguestfs] [PATCH nbdkit 2/6] checkwrite: Simplify trim/zero using nbdkit_extents_full.
On Wed, Feb 03, 2021 at 02:50:43PM -0600, Eric Blake wrote:
On 1/26/21 3:51 PM, Richard W.M. Jones wrote:
> ---
> filters/checkwrite/checkwrite.c | 96 +++++++++++++--------------------
> 1 file changed, 38 insertions(+), 58 deletions(-)
>
> diff --git a/filters/checkwrite/checkwrite.c b/filters/checkwrite/checkwrite.c
> index 68c57c37..2792d4d8 100644
> --- a/filters/checkwrite/checkwrite.c
> +++ b/filters/checkwrite/checkwrite.c
> @@ -150,67 +150,47 @@ checkwrite_trim_zero (struct nbdkit_next_ops *next_ops, void
*nxdata,
> {
> /* If the plugin supports extents, speed this up by using them. */
> if (next_ops->can_extents (nxdata)) {
> + size_t i, n;
> + CLEANUP_EXTENTS_FREE struct nbdkit_extents *exts =
> + nbdkit_extents_full (next_ops, nxdata, count, offset, 0, err);
> + if (exts == NULL)
> + return -1;
Should we instead behave like the entire region is data, instead of
reflecting back the error?
After thinking about this, I think if plugin.extents is returning
errors then we should return an error. But that's only because this
filter is designed to test copying tools, and so it should be
extra-cautious and prefer failing over trying to continue. In a
different kind of filter the trade-off would be different, and trying
to continue would make sense.
Rich.
--
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