Introduce a new IOMMUFD_OBJ_VDEVICE to represent a physical device, i.e.
iommufd_device (idev) object, against an iommufd_viommu (vIOMMU) object in
the VM. This vDEVICE object (and its structure) holds all the information
and attributes in a VM, regarding the device related to the vIOMMU.
As an initial patch, add a per-vIOMMU virtual ID. This can be:
- Virtual StreamID on a nested ARM SMMUv3, an index to a Stream Table
- Virtual DeviceID on a nested AMD IOMMU, an index to a Device Table
- Virtual ID on a nested Intel VT-D IOMMU, an index to a Context Table
Potentially, this vDEVICE structure can hold some vData for Confidential
Compute Architecture (CCA).
Add a pair of vdevice_alloc and vdevice_free in struct iommufd_viommu_ops
to allow driver-level vDEVICE structure allocations.
Similar to iommufd_viommu_alloc, add an iommufd_vdevice_alloc helper, so
IOMMU drivers can allocate core-embedded style structures.
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
include/linux/iommufd.h | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h
index 5c13c35952d8..5d61a1d2947a 100644
--- a/include/linux/iommufd.h
+++ b/include/linux/iommufd.h
@@ -31,6 +31,7 @@ enum iommufd_object_type {
IOMMUFD_OBJ_ACCESS,
IOMMUFD_OBJ_FAULT,
IOMMUFD_OBJ_VIOMMU,
+ IOMMUFD_OBJ_VDEVICE,
#ifdef CONFIG_IOMMUFD_TEST
IOMMUFD_OBJ_SELFTEST,
#endif
@@ -92,6 +93,14 @@ struct iommufd_viommu {
unsigned int type;
};
+struct iommufd_vdevice {
+ struct iommufd_object obj;
+ struct iommufd_ctx *ictx;
+ struct iommufd_device *idev;
+ struct iommufd_viommu *viommu;
+ u64 id; /* per-vIOMMU virtual ID */
+};
+
/**
* struct iommufd_viommu_ops - vIOMMU specific operations
* @free: Free all driver-specific parts of an iommufd_viommu. The memory of the
@@ -101,12 +110,24 @@ struct iommufd_viommu {
* must be defined in include/uapi/linux/iommufd.h.
* It must fully initialize the new iommu_domain before
* returning. Upon failure, ERR_PTR must be returned.
+ * @vdevice_alloc: Allocate a driver-managed iommufd_vdevice to init some driver
+ * specific structure or HW procedure. Note that the core-level
+ * structure is filled by the iommufd core after calling this op.
+ * It is suggested to call iommufd_vdevice_alloc() helper for
+ * a bundled allocation of the core and the driver structures,
+ * using the ictx pointer in the given @viommu.
+ * @vdevice_free: Free a driver-managed iommufd_vdevice to de-init its structure
+ * or HW procedure. The memory of the vdevice will be free-ed by
+ * iommufd core.
*/
struct iommufd_viommu_ops {
void (*free)(struct iommufd_viommu *viommu);
struct iommu_domain *(*domain_alloc_nested)(
struct iommufd_viommu *viommu,
const struct iommu_user_data *user_data);
+ struct iommufd_vdevice *(*vdevice_alloc)(struct iommufd_viommu *viommu,
+ struct device *dev, u64 id);
+ void (*vdevice_free)(struct iommufd_vdevice *vdev);
};
#if IS_ENABLED(CONFIG_IOMMUFD)
@@ -200,4 +221,15 @@ _iommufd_object_alloc(struct iommufd_ctx *ictx, size_t size,
ret->member.ops = viommu_ops; \
ret; \
})
+#define iommufd_vdevice_alloc(ictx, drv_struct, member) \
+ ({ \
+ static_assert( \
+ __same_type(struct iommufd_vdevice, \
+ ((struct drv_struct *)NULL)->member)); \
+ static_assert(offsetof(struct drv_struct, member.obj) == 0); \
+ container_of(_iommufd_object_alloc(ictx, \
+ sizeof(struct drv_struct), \
+ IOMMUFD_OBJ_VDEVICE), \
+ struct drv_struct, member.obj); \
+ })
#endif
--
2.43.0
On 22/10/24 11:20, Nicolin Chen wrote:
> Introduce a new IOMMUFD_OBJ_VDEVICE to represent a physical device, i.e.
> iommufd_device (idev) object, against an iommufd_viommu (vIOMMU) object in
> the VM. This vDEVICE object (and its structure) holds all the information
> and attributes in a VM, regarding the device related to the vIOMMU.
>
> As an initial patch, add a per-vIOMMU virtual ID. This can be:
> - Virtual StreamID on a nested ARM SMMUv3, an index to a Stream Table
> - Virtual DeviceID on a nested AMD IOMMU, an index to a Device Table
> - Virtual ID on a nested Intel VT-D IOMMU, an index to a Context Table
> Potentially, this vDEVICE structure can hold some vData for Confidential
> Compute Architecture (CCA).
>
> Add a pair of vdevice_alloc and vdevice_free in struct iommufd_viommu_ops
> to allow driver-level vDEVICE structure allocations.
>
> Similar to iommufd_viommu_alloc, add an iommufd_vdevice_alloc helper, so
> IOMMU drivers can allocate core-embedded style structures.
>
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> ---
> include/linux/iommufd.h | 32 ++++++++++++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h
> index 5c13c35952d8..5d61a1d2947a 100644
> --- a/include/linux/iommufd.h
> +++ b/include/linux/iommufd.h
> @@ -31,6 +31,7 @@ enum iommufd_object_type {
> IOMMUFD_OBJ_ACCESS,
> IOMMUFD_OBJ_FAULT,
> IOMMUFD_OBJ_VIOMMU,
> + IOMMUFD_OBJ_VDEVICE,
> #ifdef CONFIG_IOMMUFD_TEST
> IOMMUFD_OBJ_SELFTEST,
> #endif
> @@ -92,6 +93,14 @@ struct iommufd_viommu {
> unsigned int type;
> };
>
> +struct iommufd_vdevice {
> + struct iommufd_object obj;
> + struct iommufd_ctx *ictx;
> + struct iommufd_device *idev;
> + struct iommufd_viommu *viommu;
> + u64 id; /* per-vIOMMU virtual ID */
> +};
> +
> /**
> * struct iommufd_viommu_ops - vIOMMU specific operations
> * @free: Free all driver-specific parts of an iommufd_viommu. The memory of the
> @@ -101,12 +110,24 @@ struct iommufd_viommu {
> * must be defined in include/uapi/linux/iommufd.h.
> * It must fully initialize the new iommu_domain before
> * returning. Upon failure, ERR_PTR must be returned.
> + * @vdevice_alloc: Allocate a driver-managed iommufd_vdevice to init some driver
> + * specific structure or HW procedure. Note that the core-level
> + * structure is filled by the iommufd core after calling this op.
> + * It is suggested to call iommufd_vdevice_alloc() helper for
> + * a bundled allocation of the core and the driver structures,
> + * using the ictx pointer in the given @viommu.
> + * @vdevice_free: Free a driver-managed iommufd_vdevice to de-init its structure
> + * or HW procedure. The memory of the vdevice will be free-ed by
> + * iommufd core.
> */
> struct iommufd_viommu_ops {
> void (*free)(struct iommufd_viommu *viommu);
> struct iommu_domain *(*domain_alloc_nested)(
> struct iommufd_viommu *viommu,
> const struct iommu_user_data *user_data);
> + struct iommufd_vdevice *(*vdevice_alloc)(struct iommufd_viommu *viommu,
> + struct device *dev, u64 id);
> + void (*vdevice_free)(struct iommufd_vdevice *vdev);
> };
>
> #if IS_ENABLED(CONFIG_IOMMUFD)
> @@ -200,4 +221,15 @@ _iommufd_object_alloc(struct iommufd_ctx *ictx, size_t size,
> ret->member.ops = viommu_ops; \
> ret; \
> })
> +#define iommufd_vdevice_alloc(ictx, drv_struct, member) \
> + ({ \
> + static_assert( \
> + __same_type(struct iommufd_vdevice, \
> + ((struct drv_struct *)NULL)->member)); \
> + static_assert(offsetof(struct drv_struct, member.obj) == 0); \
> + container_of(_iommufd_object_alloc(ictx, \
> + sizeof(struct drv_struct), \
> + IOMMUFD_OBJ_VDEVICE), \
> + struct drv_struct, member.obj); \
> + })
> #endif
A nit: it hurts eyes to read:
mock_vdev = iommufd_vdevice_alloc(viommu->ictx, mock_vdevice, core);
vs.
mock_vdev = iommufd_vdevice_alloc(viommu->ictx, struct mock_vdevice, core);
as for the former I go searching for a "mock_vdevice" variable and for
the latter it is clear it is 1) a macro 2) which does some type checking.
also, it makes it impossible to pass things like typeof(..) or a type
from typedef. Thanks,
--
Alexey
On Fri, Oct 25, 2024 at 06:53:01PM +1100, Alexey Kardashevskiy wrote:
> > +#define iommufd_vdevice_alloc(ictx, drv_struct, member) \
> > + ({ \
> > + static_assert( \
> > + __same_type(struct iommufd_vdevice, \
> > + ((struct drv_struct *)NULL)->member)); \
> > + static_assert(offsetof(struct drv_struct, member.obj) == 0); \
> > + container_of(_iommufd_object_alloc(ictx, \
> > + sizeof(struct drv_struct), \
> > + IOMMUFD_OBJ_VDEVICE), \
> > + struct drv_struct, member.obj); \
> > + })
> > #endif
>
> A nit: it hurts eyes to read:
>
> mock_vdev = iommufd_vdevice_alloc(viommu->ictx, mock_vdevice, core);
>
> vs.
>
> mock_vdev = iommufd_vdevice_alloc(viommu->ictx, struct mock_vdevice, core);
>
> as for the former I go searching for a "mock_vdevice" variable and for the
> latter it is clear it is 1) a macro 2) which does some type checking.
>
> also, it makes it impossible to pass things like typeof(..) or a type from
> typedef. Thanks,
Makes sense to me
And the container_of() should not be used in these macros, the point
was to avoid it to make the PTR_ERR behavior cleraer. Just put a force
type cast
Jason
On Fri, Oct 25, 2024 at 10:20:54AM -0300, Jason Gunthorpe wrote:
> On Fri, Oct 25, 2024 at 06:53:01PM +1100, Alexey Kardashevskiy wrote:
> > > +#define iommufd_vdevice_alloc(ictx, drv_struct, member) \
> > > + ({ \
> > > + static_assert( \
> > > + __same_type(struct iommufd_vdevice, \
> > > + ((struct drv_struct *)NULL)->member)); \
> > > + static_assert(offsetof(struct drv_struct, member.obj) == 0); \
> > > + container_of(_iommufd_object_alloc(ictx, \
> > > + sizeof(struct drv_struct), \
> > > + IOMMUFD_OBJ_VDEVICE), \
> > > + struct drv_struct, member.obj); \
> > > + })
> > > #endif
> >
> > A nit: it hurts eyes to read:
> >
> > mock_vdev = iommufd_vdevice_alloc(viommu->ictx, mock_vdevice, core);
> >
> > vs.
> >
> > mock_vdev = iommufd_vdevice_alloc(viommu->ictx, struct mock_vdevice, core);
> >
> > as for the former I go searching for a "mock_vdevice" variable and for the
> > latter it is clear it is 1) a macro 2) which does some type checking.
> >
> > also, it makes it impossible to pass things like typeof(..) or a type from
> > typedef. Thanks,
>
> Makes sense to me
Ack. Will change accordingly.
> And the container_of() should not be used in these macros, the point
> was to avoid it to make the PTR_ERR behavior cleraer. Just put a force
> type cast
I recall that I changed it for a compiler complaint. But it seems
to be gone now. Will change it back.
Thanks
Nicolin
On Mon, Oct 21, 2024 at 05:20:10PM -0700, Nicolin Chen wrote:
> struct iommufd_viommu_ops {
> + struct iommufd_vdevice *(*vdevice_alloc)(struct iommufd_viommu *viommu,
> + struct device *dev, u64 id);
> + void (*vdevice_free)(struct iommufd_vdevice *vdev);
...
> +#define iommufd_vdevice_alloc(ictx, drv_struct, member) \
> + ({ \
> + static_assert( \
> + __same_type(struct iommufd_vdevice, \
> + ((struct drv_struct *)NULL)->member)); \
> + static_assert(offsetof(struct drv_struct, member.obj) == 0); \
> + container_of(_iommufd_object_alloc(ictx, \
> + sizeof(struct drv_struct), \
> + IOMMUFD_OBJ_VDEVICE), \
> + struct drv_struct, member.obj); \
> + })
Per discussion in vIRQ series [1], we might not need to expose
struct iommufd_vdevice. So, dropping most of the changes here,
and moving iommufd_device to the private header.
[1] https://lore.kernel.org/linux-iommu/ZxlGfgfwrGZGIbeF@Asurada-Nvidia/
Nicolin
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