On Thu, Nov 10, 2022 at 7:01 PM Michael S. Tsirkin <mst at redhat.com>
wrote:>
> On Thu, Nov 10, 2022 at 03:58:21PM +0800, Jason Wang wrote:
> > This patch allows device features to be provisioned via vdpa. This
> > will be useful for preserving migration compatibility between source
> > and destination:
> >
> > # vdpa dev add name dev1 mgmtdev pci/0000:02:00.0 device_features
0x300020000
> > # dev1: mac 52:54:00:12:34:56 link up link_announce false mtu 65535
> > negotiated_features CTRL_VQ VERSION_1 ACCESS_PLATFORM
> >
> > Signed-off-by: Jason Wang <jasowang at redhat.com>
> > ---
> > man/man8/vdpa-dev.8 | 10 ++++++++++
> > vdpa/include/uapi/linux/vdpa.h | 1 +
> > vdpa/vdpa.c | 27 ++++++++++++++++++++++++++-
> > 3 files changed, 37 insertions(+), 1 deletion(-)
> >
> > diff --git a/man/man8/vdpa-dev.8 b/man/man8/vdpa-dev.8
> > index 9faf3838..bb45b4a6 100644
> > --- a/man/man8/vdpa-dev.8
> > +++ b/man/man8/vdpa-dev.8
> > @@ -31,6 +31,7 @@ vdpa-dev \- vdpa device configuration
> > .I NAME
> > .B mgmtdev
> > .I MGMTDEV
> > +.RI "[ device_features " DEVICE_FEATURES " ]"
> > .RI "[ mac " MACADDR " ]"
> > .RI "[ mtu " MTU " ]"
> > .RI "[ max_vqp " MAX_VQ_PAIRS " ]"
> > @@ -74,6 +75,10 @@ Name of the new vdpa device to add.
> > Name of the management device to use for device addition.
> >
> > .PP
> > +.BI device_features " DEVICE_FEAETURES"
>
> typo
Will fix.
>
> > +- specifies the device features that is provisioned for the new vdpa
device.
>
> I propose
> the device features -> the virtio "device features"
bit-mask
>
> features sounds like it's a generic thing, here's it's
> the actual binary
>
> and maybe add "the bits can be found under
include/uapi/linux/virtio*h,
> see macros such as VIRTIO_F_ and VIRTIO_NET_F_ for specific bit
values"
That's fine.
>
> > +This is optional.
> > +
>
> and if not given what are the features?
As in the past, determined by the parent/mgmt device, do we need to
document this?
>
> > .BI mac " MACADDR"
> > - specifies the mac address for the new vdpa device.
> > This is applicable only for the network type of vdpa device. This is
optional.
> > @@ -127,6 +132,11 @@ vdpa dev add name foo mgmtdev vdpa_sim_net
> > Add the vdpa device named foo on the management device vdpa_sim_net.
> > .RE
> > .PP
> > +vdpa dev add name foo mgmtdev vdpa_sim_net device_features
0x300020000
> > +.RS 4
> > +Add the vdpa device named foo on the management device vdpa_sim_net
with device_features of 0x300020000
> > +.RE
> > +.PP
> > vdpa dev add name foo mgmtdev vdpa_sim_net mac 00:11:22:33:44:55
> > .RS 4
> > Add the vdpa device named foo on the management device vdpa_sim_net
with mac address of 00:11:22:33:44:55.
> > diff --git a/vdpa/include/uapi/linux/vdpa.h
b/vdpa/include/uapi/linux/vdpa.h
> > index 94e4dad1..7c961991 100644
> > --- a/vdpa/include/uapi/linux/vdpa.h
> > +++ b/vdpa/include/uapi/linux/vdpa.h
> > @@ -51,6 +51,7 @@ enum vdpa_attr {
> > VDPA_ATTR_DEV_QUEUE_INDEX, /* u32 */
> > VDPA_ATTR_DEV_VENDOR_ATTR_NAME, /* string */
> > VDPA_ATTR_DEV_VENDOR_ATTR_VALUE, /* u64 */
> > + VDPA_ATTR_DEV_FEATURES, /* u64 */
> >
> > /* new attributes must be added above here */
> > VDPA_ATTR_MAX,
> > diff --git a/vdpa/vdpa.c b/vdpa/vdpa.c
> > index b73e40b4..9a866d61 100644
> > --- a/vdpa/vdpa.c
> > +++ b/vdpa/vdpa.c
> > @@ -27,6 +27,7 @@
> > #define VDPA_OPT_VDEV_MTU BIT(5)
> > #define VDPA_OPT_MAX_VQP BIT(6)
> > #define VDPA_OPT_QUEUE_INDEX BIT(7)
> > +#define VDPA_OPT_VDEV_FEATURES BIT(8)
> >
> > struct vdpa_opts {
> > uint64_t present; /* flags of present items */
> > @@ -38,6 +39,7 @@ struct vdpa_opts {
> > uint16_t mtu;
> > uint16_t max_vqp;
> > uint32_t queue_idx;
> > + __u64 device_features;
> > };
> >
> > struct vdpa {
>
> why __u and not uint here?
That's possible, will do.
>
> > @@ -187,6 +189,17 @@ static int vdpa_argv_u32(struct vdpa *vdpa, int
argc, char **argv,
> > return get_u32(result, *argv, 10);
> > }
> >
> > +static int vdpa_argv_u64_hex(struct vdpa *vdpa, int argc, char
**argv,
> > + __u64 *result)
> > +{
> > + if (argc <= 0 || !*argv) {
> > + fprintf(stderr, "number expected\n");
> > + return -EINVAL;
> > + }
> > +
> > + return get_u64(result, *argv, 16);
> > +}
> > +
> > struct vdpa_args_metadata {
> > uint64_t o_flag;
> > const char *err_msg;
> > @@ -244,6 +257,10 @@ static void vdpa_opts_put(struct nlmsghdr *nlh,
struct vdpa *vdpa)
> > mnl_attr_put_u16(nlh, VDPA_ATTR_DEV_NET_CFG_MAX_VQP,
opts->max_vqp);
> > if (opts->present & VDPA_OPT_QUEUE_INDEX)
> > mnl_attr_put_u32(nlh, VDPA_ATTR_DEV_QUEUE_INDEX,
opts->queue_idx);
> > + if (opts->present & VDPA_OPT_VDEV_FEATURES) {
> > + mnl_attr_put_u64(nlh, VDPA_ATTR_DEV_FEATURES,
> > + opts->device_features);
> > + }
> > }
> >
> > static int vdpa_argv_parse(struct vdpa *vdpa, int argc, char **argv,
> > @@ -329,6 +346,14 @@ static int vdpa_argv_parse(struct vdpa *vdpa, int
argc, char **argv,
> >
> > NEXT_ARG_FWD();
> > o_found |= VDPA_OPT_QUEUE_INDEX;
> > + } else if (!strcmp(*argv, "device_features")
&&
> > + (o_optional & VDPA_OPT_VDEV_FEATURES)) {
> > + NEXT_ARG_FWD();
> > + err = vdpa_argv_u64_hex(vdpa, argc, argv,
> > +
&opts->device_features);
> > + if (err)
> > + return err;
> > + o_found |= VDPA_OPT_VDEV_FEATURES;
> > } else {
> > fprintf(stderr, "Unknown option
\"%s\"\n", *argv);
> > return -EINVAL;
>
>
> should not we validate the value we get? e.g. a mac feature
> requires that mac is supplied, etc.
This isn't an "issue" that is introduced by this patch. Management
device is free to give _F_MAC even if the mac address is not
provisioned by the userspace. So this should be the responsibility of
the parent not the netlink/vdpa tool.
> in fact hex isn't very user friendly. why not pass feature
> names instead?
This can be added on top if necessary. In fact there's a plan to
accept JSON files for provisioning.
The advantages of hex is we don't need to keep the name synced with
the new features.
Thanks
>
>
>
> > @@ -708,7 +733,7 @@ static int cmd_dev_add(struct vdpa *vdpa, int
argc, char **argv)
> > err = vdpa_argv_parse_put(nlh, vdpa, argc, argv,
> > VDPA_OPT_VDEV_MGMTDEV_HANDLE |
VDPA_OPT_VDEV_NAME,
> > VDPA_OPT_VDEV_MAC | VDPA_OPT_VDEV_MTU
|
> > - VDPA_OPT_MAX_VQP);
> > + VDPA_OPT_MAX_VQP |
VDPA_OPT_VDEV_FEATURES);
> > if (err)
> > return err;
> >
> > --
> > 2.25.1
>