[v2,06/11] iommufd: IOMMU_HWPT_ALLOC allocation with user data
Commit Message
IOMMU_HWPT_ALLOC already supports iommu_domain allocation for usersapce.
But it can only allocate hw_pagetables linked with IOAS. There are needs
to support hw_pagetable allocation with parameters specified by user. For
example, in nested translation, user needs to allocate hw_pagetable for
the stage-1 translation (e.g. a single I/O page table or a set of I/O page
tables) with user data. It also needs provide a stage-2 hw_pagetable which
is linked to the GPA IOAS.
This extends IOMMU_HWPT_ALLOC to accept user specified parameter and hwpt
ID in @pt_id field. Such as the user-managed stage-1 hwpt, which requires
a parent hwpt to point to stage-2 translation.
enum iommu_hwpt_type is defined to differentiate the user parameters use
by different usages. For the allocations that don't require user parameter,
IOMMU_HWPT_TYPE_DEFAULT is defined for backward compatibility. Other types
would be added by future iommu vendor driver extensions.
Co-developed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
drivers/iommu/iommufd/hw_pagetable.c | 87 +++++++++++++++++++++++++---
drivers/iommu/iommufd/main.c | 2 +-
include/uapi/linux/iommufd.h | 32 +++++++++-
3 files changed, 112 insertions(+), 9 deletions(-)
Comments
On 5/11/2023 10:38 PM, Yi Liu wrote:
> IOMMU_HWPT_ALLOC already supports iommu_domain allocation for usersapce.
> But it can only allocate hw_pagetables linked with IOAS. There are needs
> to support hw_pagetable allocation with parameters specified by user. For
> example, in nested translation, user needs to allocate hw_pagetable for
> the stage-1 translation (e.g. a single I/O page table or a set of I/O page
> tables) with user data. It also needs provide a stage-2 hw_pagetable which
s/provide/to provide
> is linked to the GPA IOAS.
>
> This extends IOMMU_HWPT_ALLOC to accept user specified parameter and hwpt
> ID in @pt_id field. Such as the user-managed stage-1 hwpt, which requires
> a parent hwpt to point to stage-2 translation.
>
> enum iommu_hwpt_type is defined to differentiate the user parameters use
> by different usages. For the allocations that don't require user parameter,
s/parameter/parameters
> IOMMU_HWPT_TYPE_DEFAULT is defined for backward compatibility. Other types
> would be added by future iommu vendor driver extensions.
>
> Co-developed-by: Nicolin Chen <nicolinc@nvidia.com>
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> Signed-off-by: Yi Liu <yi.l.liu@intel.com>
> ---
> drivers/iommu/iommufd/hw_pagetable.c | 87 +++++++++++++++++++++++++---
> drivers/iommu/iommufd/main.c | 2 +-
> include/uapi/linux/iommufd.h | 32 +++++++++-
> 3 files changed, 112 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
> index 73d7d9d07726..e84270eb6e49 100644
> --- a/drivers/iommu/iommufd/hw_pagetable.c
> +++ b/drivers/iommu/iommufd/hw_pagetable.c
> @@ -184,11 +184,15 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
>
> int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
> {
> + struct iommufd_hw_pagetable *hwpt, *parent = NULL;
> + union iommu_domain_user_data *data = NULL;
> struct iommu_hwpt_alloc *cmd = ucmd->cmd;
> - struct iommufd_hw_pagetable *hwpt;
> + struct iommufd_object *pt_obj;
> + const struct iommu_ops *ops;
> struct iommufd_device *idev;
> struct iommufd_ioas *ioas;
> - int rc;
> + int klen = 0;
> + int rc = 0;
>
> if (cmd->flags || cmd->__reserved)
> return -EOPNOTSUPP;
> @@ -197,15 +201,81 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
> if (IS_ERR(idev))
> return PTR_ERR(idev);
>
> - ioas = iommufd_get_ioas(ucmd->ictx, cmd->pt_id);
> - if (IS_ERR(ioas)) {
> - rc = PTR_ERR(ioas);
> + ops = dev_iommu_ops(idev->dev);
> +
> + /*
> + * All drivers support IOMMU_HWPT_TYPE_DEFAULT, so pass it through.
> + * For any other hwpt_type, check the ops->domain_alloc_user_data_len
> + * presence and its result.
> + */
> + if (cmd->hwpt_type != IOMMU_HWPT_TYPE_DEFAULT) {
> + if (!ops->domain_alloc_user_data_len) {
> + rc = -EOPNOTSUPP;
> + goto out_put_idev;
> + }
> + klen = ops->domain_alloc_user_data_len(cmd->hwpt_type);
> + if (WARN_ON(klen < 0)) {
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
Would it be better if the later check "klen" is moved here ?
if (klen) {
[...]
}
If this check fails here, there's no need to execute the code after it.
If this path is not executed, "klen" is 0, and there's no need to check it.
Do I understand it right ?
Thanks,
Jingqi
> + }
> +
> + pt_obj = iommufd_get_object(ucmd->ictx, cmd->pt_id, IOMMUFD_OBJ_ANY);
> + if (IS_ERR(pt_obj)) {
> + rc = -EINVAL;
> goto out_put_idev;
> }
>
> + switch (pt_obj->type) {
> + case IOMMUFD_OBJ_IOAS:
> + ioas = container_of(pt_obj, struct iommufd_ioas, obj);
> + break;
> + case IOMMUFD_OBJ_HW_PAGETABLE:
> + /* pt_id points HWPT only when hwpt_type is !IOMMU_HWPT_TYPE_DEFAULT */
> + if (cmd->hwpt_type == IOMMU_HWPT_TYPE_DEFAULT) {
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
> +
> + parent = container_of(pt_obj, struct iommufd_hw_pagetable, obj);
> + /*
> + * Cannot allocate user-managed hwpt linking to auto_created
> + * hwpt. If the parent hwpt is already a user-managed hwpt,
> + * don't allocate another user-managed hwpt linking to it.
> + */
> + if (parent->auto_domain || parent->parent) {
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
> + ioas = parent->ioas;
> + break;
> + default:
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
> +
> + if (klen) {
> + if (!cmd->data_len) {
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
> +
> + data = kzalloc(sizeof(*data), GFP_KERNEL);
> + if (!data) {
> + rc = -ENOMEM;
> + goto out_put_pt;
> + }
> +
> + rc = copy_struct_from_user(data, sizeof(*data),
> + u64_to_user_ptr(cmd->data_uptr),
> + cmd->data_len);
> + if (rc)
> + goto out_free_data;
> + }
> +
> mutex_lock(&ioas->mutex);
> hwpt = iommufd_hw_pagetable_alloc(ucmd->ictx, ioas, idev,
> - NULL, NULL, false);
> + parent, data, false);
> if (IS_ERR(hwpt)) {
> rc = PTR_ERR(hwpt);
> goto out_unlock;
> @@ -222,7 +292,10 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
> iommufd_object_abort_and_destroy(ucmd->ictx, &hwpt->obj);
> out_unlock:
> mutex_unlock(&ioas->mutex);
> - iommufd_put_object(&ioas->obj);
> +out_free_data:
> + kfree(data);
> +out_put_pt:
> + iommufd_put_object(pt_obj);
> out_put_idev:
> iommufd_put_object(&idev->obj);
> return rc;
> diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c
> index 5c24e8971f09..ac81403ba78e 100644
> --- a/drivers/iommu/iommufd/main.c
> +++ b/drivers/iommu/iommufd/main.c
> @@ -302,7 +302,7 @@ struct iommufd_ioctl_op {
> static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = {
> IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id),
> IOCTL_OP(IOMMU_HWPT_ALLOC, iommufd_hwpt_alloc, struct iommu_hwpt_alloc,
> - __reserved),
> + data_uptr),
> IOCTL_OP(IOMMU_DEVICE_GET_HW_INFO, iommufd_device_get_hw_info,
> struct iommu_hw_info, __reserved),
> IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl,
> diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
> index e9d42838dcbd..699e735828db 100644
> --- a/include/uapi/linux/iommufd.h
> +++ b/include/uapi/linux/iommufd.h
> @@ -347,6 +347,14 @@ struct iommu_vfio_ioas {
> };
> #define IOMMU_VFIO_IOAS _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VFIO_IOAS)
>
> +/**
> + * enum iommu_hwpt_type - IOMMU HWPT Type
> + * @IOMMU_HWPT_TYPE_DEFAULT: default
> + */
> +enum iommu_hwpt_type {
> + IOMMU_HWPT_TYPE_DEFAULT,
> +};
> +
> /**
> * struct iommu_hwpt_alloc - ioctl(IOMMU_HWPT_ALLOC)
> * @size: sizeof(struct iommu_hwpt_alloc)
> @@ -355,12 +363,31 @@ struct iommu_vfio_ioas {
> * @pt_id: The IOAS to connect this HWPT to
> * @out_hwpt_id: The ID of the new HWPT
> * @__reserved: Must be 0
> + * @hwpt_type: One of enum iommu_hwpt_type
> + * @data_len: Length of the type specific data
> + * @data_uptr: User pointer to the type specific data
> *
> * Explicitly allocate a hardware page table object. This is the same object
> * type that is returned by iommufd_device_attach() and represents the
> * underlying iommu driver's iommu_domain kernel object.
> *
> - * A HWPT will be created with the IOVA mappings from the given IOAS.
> + * A kernel-managed HWPT will be created with the mappings from the given IOAS.
> + * The @hwpt_type for its allocation can be set to IOMMU_HWPT_TYPE_DEFAULT, or
> + * another type (being listed below) to specialize a kernel-managed HWPT.
> + *
> + * A user-managed HWPT will be created from a given parent HWPT via @pt_id, in
> + * which the parent HWPT must be allocated previously via the same ioctl from a
> + * given IOAS. The @hwpt_type must not be set to IOMMU_HWPT_TYPE_DEFAULT but a
> + * pre-defined type corresponding to the underlying IOMMU hardware.
> + *
> + * If the @hwpt_type is set to IOMMU_HWPT_TYPE_DEFAULT, both the @data_len and
> + * the @data_uptr will be ignored. Otherwise, both of them must be given.
> + *
> + * +==============================+=====================================+===========+
> + * | @hwpt_type | Data structure in @data_uptr | @pt_id |
> + * +------------------------------+-------------------------------------+-----------+
> + * | IOMMU_HWPT_TYPE_DEFAULT | N/A | IOAS |
> + * +------------------------------+-------------------------------------+-----------+
> */
> struct iommu_hwpt_alloc {
> __u32 size;
> @@ -369,6 +396,9 @@ struct iommu_hwpt_alloc {
> __u32 pt_id;
> __u32 out_hwpt_id;
> __u32 __reserved;
> + __u32 hwpt_type;
> + __u32 data_len;
> + __aligned_u64 data_uptr;
> };
> #define IOMMU_HWPT_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_ALLOC)
>
> From: Yi Liu <yi.l.liu@intel.com>
> Sent: Thursday, May 11, 2023 10:39 PM
> + if (cmd->hwpt_type != IOMMU_HWPT_TYPE_DEFAULT) {
> + if (!ops->domain_alloc_user_data_len) {
> + rc = -EOPNOTSUPP;
> + goto out_put_idev;
> + }
> + klen = ops->domain_alloc_user_data_len(cmd->hwpt_type);
> + if (WARN_ON(klen < 0)) {
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
> + }
What about passing the user pointer to the iommu driver which
then does the copy so we don't need an extra @data_len()
callback for every driver?
>
> + switch (pt_obj->type) {
> + case IOMMUFD_OBJ_IOAS:
> + ioas = container_of(pt_obj, struct iommufd_ioas, obj);
> + break;
this should fail if parent is specified.
> + case IOMMUFD_OBJ_HW_PAGETABLE:
> + /* pt_id points HWPT only when hwpt_type
> is !IOMMU_HWPT_TYPE_DEFAULT */
> + if (cmd->hwpt_type == IOMMU_HWPT_TYPE_DEFAULT) {
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
> +
> + parent = container_of(pt_obj, struct iommufd_hw_pagetable,
> obj);
> + /*
> + * Cannot allocate user-managed hwpt linking to
> auto_created
> + * hwpt. If the parent hwpt is already a user-managed hwpt,
> + * don't allocate another user-managed hwpt linking to it.
> + */
> + if (parent->auto_domain || parent->parent) {
> + rc = -EINVAL;
> + goto out_put_pt;
> + }
> + ioas = parent->ioas;
for nesting why is ioas required? In concept we can just pass NULL ioas
to iommufd_hw_pagetable_alloc() for this hwpt. If within that function
there is a need to toggle ioas for the parent it can always retrieve it
from the parent hwpt.
On Wed, May 17, 2023 at 11:08:12AM +0800, Liu, Jingqi wrote:
> > + /*
> > + * All drivers support IOMMU_HWPT_TYPE_DEFAULT, so pass it through.
> > + * For any other hwpt_type, check the ops->domain_alloc_user_data_len
> > + * presence and its result.
> > + */
> > + if (cmd->hwpt_type != IOMMU_HWPT_TYPE_DEFAULT) {
> > + if (!ops->domain_alloc_user_data_len) {
> > + rc = -EOPNOTSUPP;
> > + goto out_put_idev;
> > + }
> > + klen = ops->domain_alloc_user_data_len(cmd->hwpt_type);
> > + if (WARN_ON(klen < 0)) {
> > + rc = -EINVAL;
> > + goto out_put_pt;
> > + }
> Would it be better if the later check "klen" is moved here ?
> if (klen) {
> [...]
> }
> If this check fails here, there's no need to execute the code after it.
> If this path is not executed, "klen" is 0, and there's no need to check it.
> Do I understand it right ?
Makes sense. And the klen value isn't really being used. So,
we may likely change it to a bool one. Also, I'm thinking of
forcing a !!cmd->data_len for a non-DEFAULT hwpt_type:
+ if (cmd->hwpt_type != IOMMU_HWPT_TYPE_DEFAULT) {
+ if (!cmd->data_len) {
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
+ if (!ops->domain_alloc_user_data_len) {
+ rc = -EOPNOTSUPP;
+ goto out_put_pt;
+ }
+ if (!ops->hwpt_type_is_supported(cmd->hwpt_type)) {
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
Then, for the latter part, simply:
+ if (cmd->data_len) {
+ // malloc data
+ }
Thanks
Nic
On Fri, May 19, 2023 at 09:41:00AM +0000, Tian, Kevin wrote:
> External email: Use caution opening links or attachments
>
>
> > From: Yi Liu <yi.l.liu@intel.com>
> > Sent: Thursday, May 11, 2023 10:39 PM
> > + if (cmd->hwpt_type != IOMMU_HWPT_TYPE_DEFAULT) {
> > + if (!ops->domain_alloc_user_data_len) {
> > + rc = -EOPNOTSUPP;
> > + goto out_put_idev;
> > + }
> > + klen = ops->domain_alloc_user_data_len(cmd->hwpt_type);
> > + if (WARN_ON(klen < 0)) {
> > + rc = -EINVAL;
> > + goto out_put_pt;
> > + }
> > + }
>
> What about passing the user pointer to the iommu driver which
> then does the copy so we don't need an extra @data_len()
> callback for every driver?
It's doable by letting the driver do copy_from_user(), yet I
recall that Jason suggested to keep it in the iommufd. Also,
we are reusing the ucmd_buffer for the user_data. And the klen
isn't really being used for its value here. So, it is likely
enough to have an ops->hwpt_type_is_supported.
> >
> > + switch (pt_obj->type) {
> > + case IOMMUFD_OBJ_IOAS:
> > + ioas = container_of(pt_obj, struct iommufd_ioas, obj);
> > + break;
>
> this should fail if parent is specified.
I don't think that's necessaray: the parent is NULL by default
and only specified (if IOMMUFD_OBJ_HW_PAGETABLE) by the exact
pt_id/pt_obj here.
> > + case IOMMUFD_OBJ_HW_PAGETABLE:
> > + /* pt_id points HWPT only when hwpt_type
> > is !IOMMU_HWPT_TYPE_DEFAULT */
> > + if (cmd->hwpt_type == IOMMU_HWPT_TYPE_DEFAULT) {
> > + rc = -EINVAL;
> > + goto out_put_pt;
> > + }
> > +
> > + parent = container_of(pt_obj, struct iommufd_hw_pagetable,
> > obj);
> > + /*
> > + * Cannot allocate user-managed hwpt linking to
> > auto_created
> > + * hwpt. If the parent hwpt is already a user-managed hwpt,
> > + * don't allocate another user-managed hwpt linking to it.
> > + */
> > + if (parent->auto_domain || parent->parent) {
> > + rc = -EINVAL;
> > + goto out_put_pt;
> > + }
> > + ioas = parent->ioas;
>
> for nesting why is ioas required? In concept we can just pass NULL ioas
> to iommufd_hw_pagetable_alloc() for this hwpt. If within that function
> there is a need to toggle ioas for the parent it can always retrieve it
> from the parent hwpt.
Jason suggested this for simplicity. As I replied in another
email, a user hwpt still needs ioas's refcount and mutex, so
it would otherwise have a duplicated code in the beginning of
most of hwpt_ functions:
if (hwpt->parent)
ioas = hwpt->parent->ioas;
else (hwpt->ioas)
ioas = hwpt->ioas;
else
WARN_ON(1);
Thanks
Nic
> From: Nicolin Chen <nicolinc@nvidia.com>
> Sent: Saturday, May 20, 2023 3:48 AM
>
>
> > >
> > > + switch (pt_obj->type) {
> > > + case IOMMUFD_OBJ_IOAS:
> > > + ioas = container_of(pt_obj, struct iommufd_ioas, obj);
> > > + break;
> >
> > this should fail if parent is specified.
>
> I don't think that's necessaray: the parent is NULL by default
> and only specified (if IOMMUFD_OBJ_HW_PAGETABLE) by the exact
> pt_id/pt_obj here.
I didn't get. The uAPI describes that only hwpt not ioas can be specified
in the pt_id field as the parent.
If we don't check here it means the user can specify an ioas id as the
parent?
On Wed, May 24, 2023 at 05:16:35AM +0000, Tian, Kevin wrote:
> > From: Nicolin Chen <nicolinc@nvidia.com>
> > Sent: Saturday, May 20, 2023 3:48 AM
> >
> >
> > > >
> > > > + switch (pt_obj->type) {
> > > > + case IOMMUFD_OBJ_IOAS:
> > > > + ioas = container_of(pt_obj, struct iommufd_ioas, obj);
> > > > + break;
> > >
> > > this should fail if parent is specified.
> >
> > I don't think that's necessaray: the parent is NULL by default
> > and only specified (if IOMMUFD_OBJ_HW_PAGETABLE) by the exact
> > pt_id/pt_obj here.
>
> I didn't get. The uAPI describes that only hwpt not ioas can be specified
> in the pt_id field as the parent.
>
> If we don't check here it means the user can specify an ioas id as the
> parent?
I meant that the parent pointer isn't specified at this line:
the declaration of the parent is simply NULL, and not touched
in this IOMMUFD_OBJ_IOAS case, as the parent pointer would be
only specified in the IOMMUFD_OBJ_HW_PAGETABLE case that is
behind this line.
We could add a sanity of the parent pointer, but that would
be just a NOP, right?
Thanks
Nic
> From: Nicolin Chen <nicolinc@nvidia.com>
> Sent: Wednesday, May 24, 2023 1:41 PM
>
> On Wed, May 24, 2023 at 05:16:35AM +0000, Tian, Kevin wrote:
>
> > > From: Nicolin Chen <nicolinc@nvidia.com>
> > > Sent: Saturday, May 20, 2023 3:48 AM
> > >
> > >
> > > > >
> > > > > + switch (pt_obj->type) {
> > > > > + case IOMMUFD_OBJ_IOAS:
> > > > > + ioas = container_of(pt_obj, struct iommufd_ioas, obj);
> > > > > + break;
> > > >
> > > > this should fail if parent is specified.
> > >
> > > I don't think that's necessaray: the parent is NULL by default
> > > and only specified (if IOMMUFD_OBJ_HW_PAGETABLE) by the exact
> > > pt_id/pt_obj here.
> >
> > I didn't get. The uAPI describes that only hwpt not ioas can be specified
> > in the pt_id field as the parent.
> >
> > If we don't check here it means the user can specify an ioas id as the
> > parent?
>
> I meant that the parent pointer isn't specified at this line:
> the declaration of the parent is simply NULL, and not touched
> in this IOMMUFD_OBJ_IOAS case, as the parent pointer would be
> only specified in the IOMMUFD_OBJ_HW_PAGETABLE case that is
> behind this line.
>
I see your point. As long as the type is IOAS the alloc request is
always interpreted as creating a s2 hwpt under the IOAS. Only
when it's HWPT type then it's treated as the parent.
I kept a wrong impression that there is another flag/field to mark
the parent requirement then there could be wrong combination
of setting that flag/field plus using an IOAS pt_id. 😊
@@ -184,11 +184,15 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
{
+ struct iommufd_hw_pagetable *hwpt, *parent = NULL;
+ union iommu_domain_user_data *data = NULL;
struct iommu_hwpt_alloc *cmd = ucmd->cmd;
- struct iommufd_hw_pagetable *hwpt;
+ struct iommufd_object *pt_obj;
+ const struct iommu_ops *ops;
struct iommufd_device *idev;
struct iommufd_ioas *ioas;
- int rc;
+ int klen = 0;
+ int rc = 0;
if (cmd->flags || cmd->__reserved)
return -EOPNOTSUPP;
@@ -197,15 +201,81 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
if (IS_ERR(idev))
return PTR_ERR(idev);
- ioas = iommufd_get_ioas(ucmd->ictx, cmd->pt_id);
- if (IS_ERR(ioas)) {
- rc = PTR_ERR(ioas);
+ ops = dev_iommu_ops(idev->dev);
+
+ /*
+ * All drivers support IOMMU_HWPT_TYPE_DEFAULT, so pass it through.
+ * For any other hwpt_type, check the ops->domain_alloc_user_data_len
+ * presence and its result.
+ */
+ if (cmd->hwpt_type != IOMMU_HWPT_TYPE_DEFAULT) {
+ if (!ops->domain_alloc_user_data_len) {
+ rc = -EOPNOTSUPP;
+ goto out_put_idev;
+ }
+ klen = ops->domain_alloc_user_data_len(cmd->hwpt_type);
+ if (WARN_ON(klen < 0)) {
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
+ }
+
+ pt_obj = iommufd_get_object(ucmd->ictx, cmd->pt_id, IOMMUFD_OBJ_ANY);
+ if (IS_ERR(pt_obj)) {
+ rc = -EINVAL;
goto out_put_idev;
}
+ switch (pt_obj->type) {
+ case IOMMUFD_OBJ_IOAS:
+ ioas = container_of(pt_obj, struct iommufd_ioas, obj);
+ break;
+ case IOMMUFD_OBJ_HW_PAGETABLE:
+ /* pt_id points HWPT only when hwpt_type is !IOMMU_HWPT_TYPE_DEFAULT */
+ if (cmd->hwpt_type == IOMMU_HWPT_TYPE_DEFAULT) {
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
+
+ parent = container_of(pt_obj, struct iommufd_hw_pagetable, obj);
+ /*
+ * Cannot allocate user-managed hwpt linking to auto_created
+ * hwpt. If the parent hwpt is already a user-managed hwpt,
+ * don't allocate another user-managed hwpt linking to it.
+ */
+ if (parent->auto_domain || parent->parent) {
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
+ ioas = parent->ioas;
+ break;
+ default:
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
+
+ if (klen) {
+ if (!cmd->data_len) {
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data) {
+ rc = -ENOMEM;
+ goto out_put_pt;
+ }
+
+ rc = copy_struct_from_user(data, sizeof(*data),
+ u64_to_user_ptr(cmd->data_uptr),
+ cmd->data_len);
+ if (rc)
+ goto out_free_data;
+ }
+
mutex_lock(&ioas->mutex);
hwpt = iommufd_hw_pagetable_alloc(ucmd->ictx, ioas, idev,
- NULL, NULL, false);
+ parent, data, false);
if (IS_ERR(hwpt)) {
rc = PTR_ERR(hwpt);
goto out_unlock;
@@ -222,7 +292,10 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
iommufd_object_abort_and_destroy(ucmd->ictx, &hwpt->obj);
out_unlock:
mutex_unlock(&ioas->mutex);
- iommufd_put_object(&ioas->obj);
+out_free_data:
+ kfree(data);
+out_put_pt:
+ iommufd_put_object(pt_obj);
out_put_idev:
iommufd_put_object(&idev->obj);
return rc;
@@ -302,7 +302,7 @@ struct iommufd_ioctl_op {
static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = {
IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id),
IOCTL_OP(IOMMU_HWPT_ALLOC, iommufd_hwpt_alloc, struct iommu_hwpt_alloc,
- __reserved),
+ data_uptr),
IOCTL_OP(IOMMU_DEVICE_GET_HW_INFO, iommufd_device_get_hw_info,
struct iommu_hw_info, __reserved),
IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl,
@@ -347,6 +347,14 @@ struct iommu_vfio_ioas {
};
#define IOMMU_VFIO_IOAS _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VFIO_IOAS)
+/**
+ * enum iommu_hwpt_type - IOMMU HWPT Type
+ * @IOMMU_HWPT_TYPE_DEFAULT: default
+ */
+enum iommu_hwpt_type {
+ IOMMU_HWPT_TYPE_DEFAULT,
+};
+
/**
* struct iommu_hwpt_alloc - ioctl(IOMMU_HWPT_ALLOC)
* @size: sizeof(struct iommu_hwpt_alloc)
@@ -355,12 +363,31 @@ struct iommu_vfio_ioas {
* @pt_id: The IOAS to connect this HWPT to
* @out_hwpt_id: The ID of the new HWPT
* @__reserved: Must be 0
+ * @hwpt_type: One of enum iommu_hwpt_type
+ * @data_len: Length of the type specific data
+ * @data_uptr: User pointer to the type specific data
*
* Explicitly allocate a hardware page table object. This is the same object
* type that is returned by iommufd_device_attach() and represents the
* underlying iommu driver's iommu_domain kernel object.
*
- * A HWPT will be created with the IOVA mappings from the given IOAS.
+ * A kernel-managed HWPT will be created with the mappings from the given IOAS.
+ * The @hwpt_type for its allocation can be set to IOMMU_HWPT_TYPE_DEFAULT, or
+ * another type (being listed below) to specialize a kernel-managed HWPT.
+ *
+ * A user-managed HWPT will be created from a given parent HWPT via @pt_id, in
+ * which the parent HWPT must be allocated previously via the same ioctl from a
+ * given IOAS. The @hwpt_type must not be set to IOMMU_HWPT_TYPE_DEFAULT but a
+ * pre-defined type corresponding to the underlying IOMMU hardware.
+ *
+ * If the @hwpt_type is set to IOMMU_HWPT_TYPE_DEFAULT, both the @data_len and
+ * the @data_uptr will be ignored. Otherwise, both of them must be given.
+ *
+ * +==============================+=====================================+===========+
+ * | @hwpt_type | Data structure in @data_uptr | @pt_id |
+ * +------------------------------+-------------------------------------+-----------+
+ * | IOMMU_HWPT_TYPE_DEFAULT | N/A | IOAS |
+ * +------------------------------+-------------------------------------+-----------+
*/
struct iommu_hwpt_alloc {
__u32 size;
@@ -369,6 +396,9 @@ struct iommu_hwpt_alloc {
__u32 pt_id;
__u32 out_hwpt_id;
__u32 __reserved;
+ __u32 hwpt_type;
+ __u32 data_len;
+ __aligned_u64 data_uptr;
};
#define IOMMU_HWPT_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_ALLOC)