From: "Michael S. Tsirkin" <mst@redhat.com>
To: Cornelia Huck <cohuck@redhat.com>
Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org
Subject: Re: [PATCH v2 03/24] virtio: allow __virtioXX, __leXX in config space
Date: Tue, 4 Aug 2020 10:28:06 -0400 [thread overview]
Message-ID: <20200804102730-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <20200804162340.046b719b.cohuck@redhat.com>
On Tue, Aug 04, 2020 at 04:23:40PM +0200, Cornelia Huck wrote:
> On Mon, 3 Aug 2020 16:58:46 -0400
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
>
> > Currently all config space fields are of the type __uXX.
> > This confuses people and some drivers (notably vdpa)
> > access them using CPU endian-ness - which only
> > works well for legacy or LE platforms.
> >
> > Update virtio_cread/virtio_cwrite macros to allow __virtioXX
> > and __leXX field types. Follow-up patches will convert
> > config space to use these types.
> >
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> > include/linux/virtio_config.h | 50 +++++++++++++++++++++++++++++++++--
> > 1 file changed, 48 insertions(+), 2 deletions(-)
>
> (...)
>
> > @@ -287,12 +288,57 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
> > return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
> > }
> >
> > +/*
> > + * Only the checker differentiates between __virtioXX and __uXX types. But we
> > + * try to share as much code as we can with the regular GCC build.
> > + */
> > +#if !defined(CONFIG_CC_IS_GCC) && !defined(__CHECKER__)
> > +
> > +/* Not a checker - we can keep things simple */
> > +#define __virtio_native_typeof(x) typeof(x)
> > +
> > +#else
> > +
> > +/*
> > + * We build this out of a couple of helper macros in a vain attempt to
> > + * help you keep your lunch down while reading it.
> > + */
>
> It might help with the lunch, but it still gives a slight queasiness.
> No ideas for a better version, though.
A later patch fixes this. Hopefully :)
> > +#define __virtio_pick_value(x, type, then, otherwise) \
> > + __builtin_choose_expr(__same_type(x, type), then, otherwise)
> > +
> > +#define __virtio_pick_type(x, type, then, otherwise) \
> > + __virtio_pick_value(x, type, (then)0, otherwise)
> > +
> > +#define __virtio_pick_endian(x, x16, x32, x64, otherwise) \
> > + __virtio_pick_type(x, x16, __u16, \
> > + __virtio_pick_type(x, x32, __u32, \
> > + __virtio_pick_type(x, x64, __u64, \
> > + otherwise)))
> > +
> > +#define __virtio_native_typeof(x) typeof( \
> > + __virtio_pick_type(x, __u8, __u8, \
> > + __virtio_pick_endian(x, __virtio16, __virtio32, __virtio64, \
> > + __virtio_pick_endian(x, __le16, __le32, __le64, \
> > + __virtio_pick_endian(x, __u16, __u32, __u64, \
> > + /* No other type allowed */ \
> > + (void)0)))))
> > +
> > +#endif
> > +
> > +#define __virtio_native_type(structname, member) \
> > + __virtio_native_typeof(((structname*)0)->member)
> > +
> > +#define __virtio_typecheck(structname, member, val) \
> > + /* Must match the member's type, and be integer */ \
> > + typecheck(__virtio_native_type(structname, member), (val))
> > +
> > +
>
> Acked-by: Cornelia Huck <cohuck@redhat.com>
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
next prev parent reply other threads:[~2020-08-04 14:28 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-03 20:58 [PATCH v2 00/24] virtio: config space endian-ness cleanup Michael S. Tsirkin
2020-08-03 20:58 ` [PATCH v2 01/24] virtio_balloon: fix sparse warning Michael S. Tsirkin
2020-08-03 21:25 ` David Hildenbrand
2020-08-04 14:16 ` Cornelia Huck
2020-08-03 20:58 ` [PATCH v2 02/24] virtio_ring: sparse warning fixup Michael S. Tsirkin
2020-08-04 14:18 ` Cornelia Huck
2020-08-03 20:58 ` [PATCH v2 03/24] virtio: allow __virtioXX, __leXX in config space Michael S. Tsirkin
2020-08-04 14:23 ` Cornelia Huck
2020-08-04 14:28 ` Michael S. Tsirkin [this message]
2020-08-05 6:28 ` Jason Wang
2020-08-05 11:45 ` Michael S. Tsirkin
2020-08-06 3:37 ` Jason Wang
2020-08-06 5:58 ` Michael S. Tsirkin
2020-08-07 3:26 ` Jason Wang
2020-08-03 20:58 ` [PATCH v2 04/24] virtio_9p: correct tags for config space fields Michael S. Tsirkin
2020-08-04 14:25 ` Cornelia Huck
2020-08-03 20:58 ` [PATCH v2 05/24] virtio_balloon: " Michael S. Tsirkin
2020-08-03 21:26 ` David Hildenbrand
2020-08-04 14:26 ` Cornelia Huck
2020-08-03 20:58 ` [PATCH v2 06/24] virtio_blk: " Michael S. Tsirkin
2020-08-04 14:29 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 07/24] virtio_console: " Michael S. Tsirkin
2020-08-04 14:31 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 08/24] virtio_crypto: " Michael S. Tsirkin
2020-08-04 14:32 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 09/24] virtio_fs: " Michael S. Tsirkin
2020-08-04 13:36 ` Vivek Goyal
2020-08-04 14:33 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 10/24] virtio_gpu: " Michael S. Tsirkin
2020-08-04 14:34 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 11/24] virtio_input: " Michael S. Tsirkin
2020-08-04 6:01 ` Gerd Hoffmann
2020-08-04 14:35 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 12/24] virtio_iommu: " Michael S. Tsirkin
2020-08-04 8:00 ` Jean-Philippe Brucker
2020-08-04 14:36 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 13/24] virtio_mem: " Michael S. Tsirkin
2020-08-03 21:23 ` David Hildenbrand
2020-08-04 14:37 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 14/24] virtio_net: " Michael S. Tsirkin
2020-08-04 14:44 ` Cornelia Huck
2020-08-05 13:26 ` Michael S. Tsirkin
2020-08-03 20:59 ` [PATCH v2 15/24] virtio_pmem: " Michael S. Tsirkin
2020-08-04 14:46 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 16/24] virtio_scsi: " Michael S. Tsirkin
2020-08-04 14:48 ` Cornelia Huck
2020-08-03 20:59 ` [PATCH v2 17/24] virtio_config: disallow native type fields Michael S. Tsirkin
2020-08-04 14:50 ` Cornelia Huck
2020-08-05 13:29 ` Michael S. Tsirkin
2020-08-03 21:00 ` [PATCH v2 18/24] mlxbf-tmfifo: sparse tags for config access Michael S. Tsirkin
2020-08-04 14:56 ` Cornelia Huck
2020-08-05 13:29 ` Michael S. Tsirkin
2020-08-03 21:00 ` [PATCH v2 19/24] vdpa: make sure set_features in invoked for legacy Michael S. Tsirkin
2020-08-05 6:14 ` Jason Wang
2020-08-05 11:40 ` Michael S. Tsirkin
2020-08-06 3:23 ` Jason Wang
2020-08-06 5:53 ` Michael S. Tsirkin
2020-08-06 7:27 ` Jason Wang
2020-08-06 10:00 ` Michael S. Tsirkin
2020-08-07 3:00 ` Jason Wang
2020-08-03 21:00 ` [PATCH v2 20/24] vhost/vdpa: switch to new helpers Michael S. Tsirkin
2020-08-03 21:00 ` [PATCH v2 21/24] virtio_vdpa: legacy features handling Michael S. Tsirkin
2020-08-03 21:00 ` [PATCH v2 22/24] vdpa_sim: fix endian-ness of config space Michael S. Tsirkin
2020-08-05 6:21 ` Jason Wang
2020-08-05 11:44 ` Michael S. Tsirkin
2020-08-05 12:06 ` Michael S. Tsirkin
2020-08-06 3:23 ` Jason Wang
2020-08-03 21:00 ` [PATCH v2 23/24] virtio_config: cread/write cleanup Michael S. Tsirkin
2020-08-03 21:00 ` [PATCH v2 24/24] virtio_config: rewrite using _Generic Michael S. Tsirkin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200804102730-mutt-send-email-mst@kernel.org \
--to=mst@redhat.com \
--cc=cohuck@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=virtualization@lists.linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).