[Libguestfs] [PATCH nbdkit v2 7/7] New filter: nbdkit-block-size-constraint-filter

[Richard W.M. Jones]

On Fri, Feb 18, 2022 at 12:25:56PM +0000, Richard W.M. Jones wrote:
> On Thu, Feb 17, 2022 at 04:44:56PM -0600, Eric Blake wrote:
> > On Thu, Feb 17, 2022 at 10:00:52PM +0000, Richard W.M. Jones wrote:
> > > On Thu, Feb 17, 2022 at 03:58:07PM -0600, Eric Blake wrote:
> > > > The NBD protocol spec recommends EINVAL (rather than EIO) for requests
> > > > that violate block size constraints.  Do we want to hardcode EINVAL,
> > > > or else tweak the error policy to allow the user to specify which
> > > > errno to provide?
> > > 
> > > I err on not overthinking this.  I'll change it to EINVAL, and if ever
> > > we need to choose another errno then we can add a knob for it.
> > 
> > Just noticed this XXX comment that we should now be able to test with
> > blocksize-policy of error:
> > https://gitlab.com/nbdkit/libnbd/-/blob/master/tests/errors.c#L464
> 
> Wow, that test is huge!  Looking at the history it seems to have
> accreted new tests over several years.
> 
> I've partially split it into smaller, more mangeable tests.  There's
> more to be done before I can add that check.  I may have another go at
> this later.
> 
> https://gitlab.com/nbdkit/libnbd/-/commit/3f57d7a37a7c5a1d8495f3bc1880e22da38d9f65

I fixed this and added the test:

https://gitlab.com/nbdkit/libnbd/-/commit/6f5fec2ec3728e67475087fa055c8bd05b268b8e

and that test revealed a bug in the new filter (in nbdkit):

https://gitlab.com/nbdkit/nbdkit/-/commit/f5dfd30f380ef1185f6fcca4e6345e0434fb8039

Rich.

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