| Message ID | 20230511143844.22693-7-yi.l.liu@intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | iommufd: Add nesting infrastructure | expand |
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
> 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. 😊
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; + } + } + + 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)