RE: [PATCH v2 7/8] iommu/vt-d: Delete supervisor/kernel SVA

Tian, Kevin
2022-03-18T06:17:41Z

> From: Jacob Pan <jacob.jun.pan@linux.intel.com>
> Sent: Tuesday, March 15, 2022 1:07 PM
>
> In-kernel DMA with PASID should use DMA API now, remove supervisor
> PASID
> SVA support. Remove special cases in bind mm and page request service.
>
> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>

so you removed all the references to SVM_FLAG_SUPERVISOR_MODE
but the definition is still kept in include/linux/intel-svm.h...

> ---
> drivers/iommu/intel/svm.c | 42 ++++++++-------------------------------
> 1 file changed, 8 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
> index 2c53689da461..37d6218f173b 100644
> --- a/drivers/iommu/intel/svm.c
> +++ b/drivers/iommu/intel/svm.c
> @@ -516,11 +516,10 @@ static void intel_svm_free_pasid(struct mm_struct
> *mm)
>
> static struct iommu_sva *intel_svm_bind_mm(struct intel_iommu *iommu,
> struct device *dev,
> - struct mm_struct *mm,
> - unsigned int flags)
> + struct mm_struct *mm)
> {
> struct device_domain_info *info = get_domain_info(dev);
> - unsigned long iflags, sflags;
> + unsigned long iflags, sflags = 0;
> struct intel_svm_dev *sdev;
> struct intel_svm *svm;
> int ret = 0;
> @@ -533,16 +532,13 @@ static struct iommu_sva
> *intel_svm_bind_mm(struct intel_iommu *iommu,
>
> svm->pasid = mm->pasid;
> svm->mm = mm;
> - svm->flags = flags;
> INIT_LIST_HEAD_RCU(&svm->devs);
>
> - if (!(flags & SVM_FLAG_SUPERVISOR_MODE)) {
> - svm->notifier.ops = &intel_mmuops;
> - ret = mmu_notifier_register(&svm->notifier, mm);
> - if (ret) {
> - kfree(svm);
> - return ERR_PTR(ret);
> - }
> + svm->notifier.ops = &intel_mmuops;
> + ret = mmu_notifier_register(&svm->notifier, mm);
> + if (ret) {
> + kfree(svm);
> + return ERR_PTR(ret);
> }
>
> ret = pasid_private_add(svm->pasid, svm);
> @@ -583,8 +579,6 @@ static struct iommu_sva *intel_svm_bind_mm(struct
> intel_iommu *iommu,
> }
>
> /* Setup the pasid table: */
> - sflags = (flags & SVM_FLAG_SUPERVISOR_MODE) ?
> - PASID_FLAG_SUPERVISOR_MODE : 0;
> sflags |= cpu_feature_enabled(X86_FEATURE_LA57) ?
> PASID_FLAG_FL5LP : 0;
> spin_lock_irqsave(&iommu->lock, iflags);
> ret = intel_pasid_setup_first_level(iommu, dev, mm->pgd, mm-
> >pasid,
> @@ -957,7 +951,7 @@ static irqreturn_t prq_event_thread(int irq, void *d)
> * to unbind the mm while any page faults are
> outstanding.
> */
> svm = pasid_private_find(req->pasid);
> - if (IS_ERR_OR_NULL(svm) || (svm->flags &
> SVM_FLAG_SUPERVISOR_MODE))
> + if (IS_ERR_OR_NULL(svm))
> goto bad_req;
> }
>
> @@ -1011,29 +1005,9 @@ static irqreturn_t prq_event_thread(int irq, void
> *d)
> struct iommu_sva *intel_svm_bind(struct device *dev, struct mm_struct
> *mm, void *drvdata)
> {
> struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL);
> - unsigned int flags = 0;
> struct iommu_sva *sva;
> int ret;
>
> - if (drvdata)
> - flags = *(unsigned int *)drvdata;
> -
> - if (flags & SVM_FLAG_SUPERVISOR_MODE) {
> - if (!ecap_srs(iommu->ecap)) {
> - dev_err(dev, "%s: Supervisor PASID not supported\n",
> - iommu->name);
> - return ERR_PTR(-EOPNOTSUPP);
> - }
> -
> - if (mm) {
> - dev_err(dev, "%s: Supervisor PASID with user
> provided mm\n",
> - iommu->name);
> - return ERR_PTR(-EINVAL);
> - }
> -
> - mm = &init_mm;
> - }
> -
> mutex_lock(&pasid_mutex);
> ret = intel_svm_alloc_pasid(dev, mm, flags);
> if (ret) {
> --
> 2.25.1