diff options
| author |   David Woodhouse <David.Woodhouse@intel.com> | 2015-10-15 13:59:14 +0100 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2015-10-15 15:35:32 +0100 |
| commit | 569e4f7782fb92d0e1b395b5fb01de642dd74dcf (patch) | |
| tree | ef6aabacf8524f4adbcf7b0b9fbc0c2d3c2b282a | |
| parent | iommu/vt-d: Add callback to device driver on page faults (diff) | |
| download | wireguard-linux-569e4f7782fb92d0e1b395b5fb01de642dd74dcf.tar.xz wireguard-linux-569e4f7782fb92d0e1b395b5fb01de642dd74dcf.zip | |
iommu/vt-d: Implement SVM_FLAG_PRIVATE_PASID to allocate unique PASIDs
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| -rw-r--r-- | drivers/iommu/intel-svm.c | 6 | ||||
| -rw-r--r-- | include/linux/intel-iommu.h | 1 | ||||
| -rw-r--r-- | include/linux/intel-svm.h | 11 |
3 files changed, 16 insertions, 2 deletions
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index 006e95dd64ae..89d4d47d0ab3 100644 --- a/drivers/iommu/intel-svm.c +++ b/drivers/iommu/intel-svm.c @@ -285,11 +285,12 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ pasid_max = 1 << 20; mutex_lock(&pasid_mutex); - if (pasid) { + if (pasid && !(flags & SVM_FLAG_PRIVATE_PASID)) { int i; idr_for_each_entry(&iommu->pasid_idr, svm, i) { - if (svm->mm != current->mm) + if (svm->mm != current->mm || + (svm->flags & SVM_FLAG_PRIVATE_PASID)) continue; if (svm->pasid >= pasid_max) { @@ -355,6 +356,7 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ svm->pasid = ret; svm->notifier.ops = &intel_mmuops; svm->mm = get_task_mm(current); + svm->flags = flags; INIT_LIST_HEAD_RCU(&svm->devs); ret = -ENOMEM; if (!svm->mm || (ret = mmu_notifier_register(&svm->notifier, svm->mm))) { diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h index 57be14fce640..821273ca4873 100644 --- a/include/linux/intel-iommu.h +++ b/include/linux/intel-iommu.h @@ -489,6 +489,7 @@ struct intel_svm { struct mmu_notifier notifier; struct mm_struct *mm; struct intel_iommu *iommu; + int flags; int pasid; struct list_head devs; }; diff --git a/include/linux/intel-svm.h b/include/linux/intel-svm.h index 239f8a13a332..dd94ab45a4db 100644 --- a/include/linux/intel-svm.h +++ b/include/linux/intel-svm.h @@ -31,6 +31,17 @@ struct svm_dev_ops { #define SVM_REQ_EXEC (1<<1) #define SVM_REQ_PRIV (1<<0) + +/* + * The SVM_FLAG_PRIVATE_PASID flag requests a PASID which is *not* the "main" + * PASID for the current process. Even if a PASID already exists, a new one + * will be allocated. And the PASID allocated with SVM_FLAG_PRIVATE_PASID + * will not be given to subsequent callers. This facility allows a driver to + * disambiguate between multiple device contexts which access the same MM, + * if there is no other way to do so. It should be used sparingly, if at all. + */ +#define SVM_FLAG_PRIVATE_PASID (1<<0) + /** * intel_svm_bind_mm() - Bind the current process to a PASID * @dev: Device to be granted acccess |