| Message ID | 1650646263-22047-5-git-send-email-olekstysh@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | virtio: Solution to restrict memory access under Xen using xen-grant DMA-mapping layer | expand |
On Fri, 22 Apr 2022, Oleksandr Tyshchenko wrote: > From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > Introduce Xen specific binding for the virtualized device (e.g. virtio) > to be used by Xen grant DMA-mapping layer in the subsequent commit. > > This binding indicates that Xen grant mappings scheme needs to be > enabled for the device which DT node contains that property and specifies > the ID of Xen domain where the corresponding backend resides. The ID > (domid) is used as an argument to the grant mapping APIs. > > This is needed for the option to restrict memory access using Xen grant > mappings to work which primary goal is to enable using virtio devices > in Xen guests. > > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Looks OK to me. Just a couple of grammar improvements below. Aside from those, I have no further comments. > --- > Changes RFC -> V1: > - update commit subject/description and text in description > - move to devicetree/bindings/arm/ > --- > .../devicetree/bindings/arm/xen,dev-domid.yaml | 37 ++++++++++++++++++++++ > 1 file changed, 37 insertions(+) > create mode 100644 Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > > diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > new file mode 100644 > index 00000000..ef0f747 > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > @@ -0,0 +1,37 @@ > +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/arm/xen,dev-domid.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Xen specific binding for the virtualized device (e.g. virtio) NIT: Xen specific binding for virtualized devices (e.g. virtio) > +maintainers: > + - Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > + > +select: true > + > +description: > + This binding indicates that Xen grant mappings scheme needs to be enabled > + for that device and specifies the ID of Xen domain where the corresponding > + device (backend) resides. This is needed for the option to restrict memory > + access using Xen grant mappings to work. NIT: This binding indicates that Xen grant mappings need to be enabled for the device, and it specifies the ID of the domain where the corresponding device (backend) resides. The property is required to restrict memory access using Xen grant mappings. > +properties: > + xen,dev-domid: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: > + The domid (domain ID) of the domain where the device (backend) is running. > + > +additionalProperties: true > + > +examples: > + - | > + virtio_block@3000 { > + compatible = "virtio,mmio"; > + reg = <0x3000 0x100>; > + interrupts = <41>; > + > + /* The device is located in Xen domain with ID 1 */ > + xen,dev-domid = <1>; > + };
On 23.04.22 02:00, Stefano Stabellini wrote: Hello Stefano > On Fri, 22 Apr 2022, Oleksandr Tyshchenko wrote: >> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >> >> Introduce Xen specific binding for the virtualized device (e.g. virtio) >> to be used by Xen grant DMA-mapping layer in the subsequent commit. >> >> This binding indicates that Xen grant mappings scheme needs to be >> enabled for the device which DT node contains that property and specifies >> the ID of Xen domain where the corresponding backend resides. The ID >> (domid) is used as an argument to the grant mapping APIs. >> >> This is needed for the option to restrict memory access using Xen grant >> mappings to work which primary goal is to enable using virtio devices >> in Xen guests. >> >> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > Looks OK to me. Just a couple of grammar improvements below. Aside from > those, I have no further comments. thank you, I agree with proposed comments, will update > > >> --- >> Changes RFC -> V1: >> - update commit subject/description and text in description >> - move to devicetree/bindings/arm/ >> --- >> .../devicetree/bindings/arm/xen,dev-domid.yaml | 37 ++++++++++++++++++++++ >> 1 file changed, 37 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> >> diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> new file mode 100644 >> index 00000000..ef0f747 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> @@ -0,0 +1,37 @@ >> +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) >> +%YAML 1.2 >> +--- >> +$id: http://devicetree.org/schemas/arm/xen,dev-domid.yaml# >> +$schema: http://devicetree.org/meta-schemas/core.yaml# >> + >> +title: Xen specific binding for the virtualized device (e.g. virtio) > NIT: Xen specific binding for virtualized devices (e.g. virtio) > > >> +maintainers: >> + - Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >> + >> +select: true >> + >> +description: >> + This binding indicates that Xen grant mappings scheme needs to be enabled >> + for that device and specifies the ID of Xen domain where the corresponding >> + device (backend) resides. This is needed for the option to restrict memory >> + access using Xen grant mappings to work. > NIT: > > This binding indicates that Xen grant mappings need to be enabled for > the device, and it specifies the ID of the domain where the > corresponding device (backend) resides. The property is required to > restrict memory access using Xen grant mappings. > > >> +properties: >> + xen,dev-domid: >> + $ref: /schemas/types.yaml#/definitions/uint32 >> + description: >> + The domid (domain ID) of the domain where the device (backend) is running. >> + >> +additionalProperties: true >> + >> +examples: >> + - | >> + virtio_block@3000 { >> + compatible = "virtio,mmio"; >> + reg = <0x3000 0x100>; >> + interrupts = <41>; >> + >> + /* The device is located in Xen domain with ID 1 */ >> + xen,dev-domid = <1>; >> + };
On Fri, Apr 22, 2022 at 07:51:01PM +0300, Oleksandr Tyshchenko wrote: > From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > Introduce Xen specific binding for the virtualized device (e.g. virtio) > to be used by Xen grant DMA-mapping layer in the subsequent commit. > > This binding indicates that Xen grant mappings scheme needs to be > enabled for the device which DT node contains that property and specifies > the ID of Xen domain where the corresponding backend resides. The ID > (domid) is used as an argument to the grant mapping APIs. > > This is needed for the option to restrict memory access using Xen grant > mappings to work which primary goal is to enable using virtio devices > in Xen guests. > > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > --- > Changes RFC -> V1: > - update commit subject/description and text in description > - move to devicetree/bindings/arm/ > --- > .../devicetree/bindings/arm/xen,dev-domid.yaml | 37 ++++++++++++++++++++++ > 1 file changed, 37 insertions(+) > create mode 100644 Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > > diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > new file mode 100644 > index 00000000..ef0f747 > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > @@ -0,0 +1,37 @@ > +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/arm/xen,dev-domid.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Xen specific binding for the virtualized device (e.g. virtio) > + > +maintainers: > + - Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > + > +select: true Do we really need to support this property everywhere? > + > +description: > + This binding indicates that Xen grant mappings scheme needs to be enabled > + for that device and specifies the ID of Xen domain where the corresponding > + device (backend) resides. This is needed for the option to restrict memory > + access using Xen grant mappings to work. > + > +properties: > + xen,dev-domid: > + $ref: /schemas/types.yaml#/definitions/uint32 > + description: > + The domid (domain ID) of the domain where the device (backend) is running. > + > +additionalProperties: true > + > +examples: > + - | > + virtio_block@3000 { virtio@3000 > + compatible = "virtio,mmio"; > + reg = <0x3000 0x100>; > + interrupts = <41>; > + > + /* The device is located in Xen domain with ID 1 */ > + xen,dev-domid = <1>; This fails validation: Documentation/devicetree/bindings/arm/xen,dev-domid.example.dtb: virtio_block@3000: xen,dev-domid: [[1]] is not of type 'object' From schema: /home/rob/proj/git/linux-dt/Documentation/devicetree/bindings/virtio/mmio.yaml The property has to be added to the virtio/mmio.yaml schema. If it is not needed elsewhere, then *just* add the property there. Rob
On 03.05.22 00:59, Rob Herring wrote: Hello Rob > On Fri, Apr 22, 2022 at 07:51:01PM +0300, Oleksandr Tyshchenko wrote: >> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >> >> Introduce Xen specific binding for the virtualized device (e.g. virtio) >> to be used by Xen grant DMA-mapping layer in the subsequent commit. >> >> This binding indicates that Xen grant mappings scheme needs to be >> enabled for the device which DT node contains that property and specifies >> the ID of Xen domain where the corresponding backend resides. The ID >> (domid) is used as an argument to the grant mapping APIs. >> >> This is needed for the option to restrict memory access using Xen grant >> mappings to work which primary goal is to enable using virtio devices >> in Xen guests. >> >> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >> --- >> Changes RFC -> V1: >> - update commit subject/description and text in description >> - move to devicetree/bindings/arm/ >> --- >> .../devicetree/bindings/arm/xen,dev-domid.yaml | 37 ++++++++++++++++++++++ >> 1 file changed, 37 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> >> diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> new file mode 100644 >> index 00000000..ef0f747 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> @@ -0,0 +1,37 @@ >> +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) >> +%YAML 1.2 >> +--- >> +$id: http://devicetree.org/schemas/arm/xen,dev-domid.yaml# >> +$schema: http://devicetree.org/meta-schemas/core.yaml# >> + >> +title: Xen specific binding for the virtualized device (e.g. virtio) >> + >> +maintainers: >> + - Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >> + >> +select: true > Do we really need to support this property everywhere? From my understanding - yes. As, I think, any device node describing virtulized device in the guest device tree can have this property. Initially (in the RFC series) the "solution to restrict memory access using Xen grant mappings" was virtio-specific. Although the support of virtio is a primary target of this series, we decided to generalize this work and expand it to any device [1]. So the Xen grant mappings scheme (this property to be used for) can be theoretically used for any device emulated by the Xen backend. >> + >> +description: >> + This binding indicates that Xen grant mappings scheme needs to be enabled >> + for that device and specifies the ID of Xen domain where the corresponding >> + device (backend) resides. This is needed for the option to restrict memory >> + access using Xen grant mappings to work. >> + >> +properties: >> + xen,dev-domid: >> + $ref: /schemas/types.yaml#/definitions/uint32 >> + description: >> + The domid (domain ID) of the domain where the device (backend) is running. >> + >> +additionalProperties: true >> + >> +examples: >> + - | >> + virtio_block@3000 { > virtio@3000 ok, will change > >> + compatible = "virtio,mmio"; >> + reg = <0x3000 0x100>; >> + interrupts = <41>; >> + >> + /* The device is located in Xen domain with ID 1 */ >> + xen,dev-domid = <1>; > This fails validation: > > Documentation/devicetree/bindings/arm/xen,dev-domid.example.dtb: virtio_block@3000: xen,dev-domid: [[1]] is not of type 'object' > From schema: /home/rob/proj/git/linux-dt/Documentation/devicetree/bindings/virtio/mmio.yaml Thank you for pointing this out, my fault, I haven't "properly" checked this before. I think, we need to remove "compatible = "virtio,mmio"; here diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml index 2daa8aa..d2f2140 100644 --- a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml @@ -28,7 +28,7 @@ additionalProperties: true examples: - | virtio_block@3000 { - compatible = "virtio,mmio"; + /* ... */ reg = <0x3000 0x100>; interrupts = <41>; > > The property has to be added to the virtio/mmio.yaml schema. If it is > not needed elsewhere, then *just* add the property there. As I described above, the property is not virtio specific and can be used for any virtualized device for which Xen grant mappings scheme needs to be enabled (xen-grant DMA-mapping layer). [1] https://lore.kernel.org/xen-devel/alpine.DEB.2.22.394.2204181202080.915916@ubuntu-linux-20-04-desktop/ > > Rob
On Tue, May 03, 2022 at 08:09:32PM +0300, Oleksandr wrote: > > On 03.05.22 00:59, Rob Herring wrote: > > Hello Rob > > > > On Fri, Apr 22, 2022 at 07:51:01PM +0300, Oleksandr Tyshchenko wrote: > > > From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > > > > > Introduce Xen specific binding for the virtualized device (e.g. virtio) > > > to be used by Xen grant DMA-mapping layer in the subsequent commit. > > > > > > This binding indicates that Xen grant mappings scheme needs to be > > > enabled for the device which DT node contains that property and specifies > > > the ID of Xen domain where the corresponding backend resides. The ID > > > (domid) is used as an argument to the grant mapping APIs. > > > > > > This is needed for the option to restrict memory access using Xen grant > > > mappings to work which primary goal is to enable using virtio devices > > > in Xen guests. > > > > > > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > > --- > > > Changes RFC -> V1: > > > - update commit subject/description and text in description > > > - move to devicetree/bindings/arm/ > > > --- > > > .../devicetree/bindings/arm/xen,dev-domid.yaml | 37 ++++++++++++++++++++++ > > > 1 file changed, 37 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > > > > > > diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > > > new file mode 100644 > > > index 00000000..ef0f747 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > > > @@ -0,0 +1,37 @@ > > > +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/arm/xen,dev-domid.yaml# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > + > > > +title: Xen specific binding for the virtualized device (e.g. virtio) > > > + > > > +maintainers: > > > + - Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > > + > > > +select: true > > Do we really need to support this property everywhere? > > From my understanding - yes. > > As, I think, any device node describing virtulized device in the guest > device tree can have this property. Initially (in the RFC series) the > "solution to restrict memory access using Xen grant mappings" was > virtio-specific. > > Although the support of virtio is a primary target of this series, we > decided to generalize this work and expand it to any device [1]. So the Xen > grant mappings scheme (this property to be used for) can be theoretically > used for any device emulated by the Xen backend. > > > > > + > > > +description: > > > + This binding indicates that Xen grant mappings scheme needs to be enabled > > > + for that device and specifies the ID of Xen domain where the corresponding > > > + device (backend) resides. This is needed for the option to restrict memory > > > + access using Xen grant mappings to work. > > > + > > > +properties: > > > + xen,dev-domid: > > > + $ref: /schemas/types.yaml#/definitions/uint32 > > > + description: > > > + The domid (domain ID) of the domain where the device (backend) is running. > > > + > > > +additionalProperties: true > > > + > > > +examples: > > > + - | > > > + virtio_block@3000 { > > virtio@3000 > > ok, will change > > > > > > > + compatible = "virtio,mmio"; > > > + reg = <0x3000 0x100>; > > > + interrupts = <41>; > > > + > > > + /* The device is located in Xen domain with ID 1 */ > > > + xen,dev-domid = <1>; > > This fails validation: > > > > Documentation/devicetree/bindings/arm/xen,dev-domid.example.dtb: virtio_block@3000: xen,dev-domid: [[1]] is not of type 'object' > > From schema: /home/rob/proj/git/linux-dt/Documentation/devicetree/bindings/virtio/mmio.yaml > > Thank you for pointing this out, my fault, I haven't "properly" checked this > before. I think, we need to remove "compatible = "virtio,mmio"; here Uhh, no. That just means the example is incomplete. You need to add this property or reference this schema from virtio/mmio.yaml. > diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > index 2daa8aa..d2f2140 100644 > --- a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml > @@ -28,7 +28,7 @@ additionalProperties: true > examples: > - | > virtio_block@3000 { > - compatible = "virtio,mmio"; > + /* ... */ > reg = <0x3000 0x100>; > interrupts = <41>; > > > > > > > The property has to be added to the virtio/mmio.yaml schema. If it is > > not needed elsewhere, then *just* add the property there. > > As I described above, the property is not virtio specific and can be used > for any virtualized device for which Xen grant mappings scheme needs to be > enabled (xen-grant DMA-mapping layer). But that's a finite list of devices, right? In any case, you have to list the property anywhere it can be used. Rob
On 04.05.22 03:02, Rob Herring wrote: Hello Rob > On Tue, May 03, 2022 at 08:09:32PM +0300, Oleksandr wrote: >> On 03.05.22 00:59, Rob Herring wrote: >> >> Hello Rob >> >> >>> On Fri, Apr 22, 2022 at 07:51:01PM +0300, Oleksandr Tyshchenko wrote: >>>> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >>>> >>>> Introduce Xen specific binding for the virtualized device (e.g. virtio) >>>> to be used by Xen grant DMA-mapping layer in the subsequent commit. >>>> >>>> This binding indicates that Xen grant mappings scheme needs to be >>>> enabled for the device which DT node contains that property and specifies >>>> the ID of Xen domain where the corresponding backend resides. The ID >>>> (domid) is used as an argument to the grant mapping APIs. >>>> >>>> This is needed for the option to restrict memory access using Xen grant >>>> mappings to work which primary goal is to enable using virtio devices >>>> in Xen guests. >>>> >>>> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >>>> --- >>>> Changes RFC -> V1: >>>> - update commit subject/description and text in description >>>> - move to devicetree/bindings/arm/ >>>> --- >>>> .../devicetree/bindings/arm/xen,dev-domid.yaml | 37 ++++++++++++++++++++++ >>>> 1 file changed, 37 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >>>> >>>> diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >>>> new file mode 100644 >>>> index 00000000..ef0f747 >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >>>> @@ -0,0 +1,37 @@ >>>> +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) >>>> +%YAML 1.2 >>>> +--- >>>> +$id: http://devicetree.org/schemas/arm/xen,dev-domid.yaml# >>>> +$schema: http://devicetree.org/meta-schemas/core.yaml# >>>> + >>>> +title: Xen specific binding for the virtualized device (e.g. virtio) >>>> + >>>> +maintainers: >>>> + - Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >>>> + >>>> +select: true >>> Do we really need to support this property everywhere? >> From my understanding - yes. >> >> As, I think, any device node describing virtulized device in the guest >> device tree can have this property. Initially (in the RFC series) the >> "solution to restrict memory access using Xen grant mappings" was >> virtio-specific. >> >> Although the support of virtio is a primary target of this series, we >> decided to generalize this work and expand it to any device [1]. So the Xen >> grant mappings scheme (this property to be used for) can be theoretically >> used for any device emulated by the Xen backend. >> >> >>>> + >>>> +description: >>>> + This binding indicates that Xen grant mappings scheme needs to be enabled >>>> + for that device and specifies the ID of Xen domain where the corresponding >>>> + device (backend) resides. This is needed for the option to restrict memory >>>> + access using Xen grant mappings to work. >>>> + >>>> +properties: >>>> + xen,dev-domid: >>>> + $ref: /schemas/types.yaml#/definitions/uint32 >>>> + description: >>>> + The domid (domain ID) of the domain where the device (backend) is running. >>>> + >>>> +additionalProperties: true >>>> + >>>> +examples: >>>> + - | >>>> + virtio_block@3000 { >>> virtio@3000 >> ok, will change >> >> >>>> + compatible = "virtio,mmio"; >>>> + reg = <0x3000 0x100>; >>>> + interrupts = <41>; >>>> + >>>> + /* The device is located in Xen domain with ID 1 */ >>>> + xen,dev-domid = <1>; >>> This fails validation: >>> >>> Documentation/devicetree/bindings/arm/xen,dev-domid.example.dtb: virtio_block@3000: xen,dev-domid: [[1]] is not of type 'object' >>> From schema: /home/rob/proj/git/linux-dt/Documentation/devicetree/bindings/virtio/mmio.yaml >> Thank you for pointing this out, my fault, I haven't "properly" checked this >> before. I think, we need to remove "compatible = "virtio,mmio"; here > Uhh, no. That just means the example is incomplete. You need to add this > property or reference this schema from virtio/mmio.yaml. ok, I got it > > >> diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> index 2daa8aa..d2f2140 100644 >> --- a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml >> @@ -28,7 +28,7 @@ additionalProperties: true >> examples: >> - | >> virtio_block@3000 { >> - compatible = "virtio,mmio"; >> + /* ... */ >> reg = <0x3000 0x100>; >> interrupts = <41>; >> >> >> >>> The property has to be added to the virtio/mmio.yaml schema. If it is >>> not needed elsewhere, then *just* add the property there. >> As I described above, the property is not virtio specific and can be used >> for any virtualized device for which Xen grant mappings scheme needs to be >> enabled (xen-grant DMA-mapping layer). > But that's a finite list of devices, right? Right > In any case, you have to > list the property anywhere it can be used. Agree If I got it right, we need to add to virtio/mmio.yaml something like: diff --git a/Documentation/devicetree/bindings/virtio/mmio.yaml b/Documentation/devicetree/bindings/virtio/mmio.yaml index 10c22b5..29a0932 100644 --- a/Documentation/devicetree/bindings/virtio/mmio.yaml +++ b/Documentation/devicetree/bindings/virtio/mmio.yaml @@ -13,6 +13,9 @@ description: See https://www.oasis-open.org/committees/tc_home.php?wg_abbrev=virtio for more details. +allOf: + - $ref: /schemas/arm/xen,dev-domid.yaml# + properties: compatible: const: virtio,mmio @@ -33,6 +36,10 @@ properties: description: Required for devices making accesses thru an IOMMU. maxItems: 1 + xen,dev-domid: + description: Required when Xen grant mappings need to be enabled for device. + $ref: /schemas/types.yaml#/definitions/uint32 + required: - compatible - reg This passed validation. Could you please clarify, is my understanding correct? > > Rob
diff --git a/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml new file mode 100644 index 00000000..ef0f747 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/xen,dev-domid.yaml @@ -0,0 +1,37 @@ +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/arm/xen,dev-domid.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Xen specific binding for the virtualized device (e.g. virtio) + +maintainers: + - Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> + +select: true + +description: + This binding indicates that Xen grant mappings scheme needs to be enabled + for that device and specifies the ID of Xen domain where the corresponding + device (backend) resides. This is needed for the option to restrict memory + access using Xen grant mappings to work. + +properties: + xen,dev-domid: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + The domid (domain ID) of the domain where the device (backend) is running. + +additionalProperties: true + +examples: + - | + virtio_block@3000 { + compatible = "virtio,mmio"; + reg = <0x3000 0x100>; + interrupts = <41>; + + /* The device is located in Xen domain with ID 1 */ + xen,dev-domid = <1>; + };