Commit 569e4f77 authored by David Woodhouse's avatar David Woodhouse
Browse files

iommu/vt-d: Implement SVM_FLAG_PRIVATE_PASID to allocate unique PASIDs 



Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
parent 0204a496

drivers/iommu/intel-svm.c

+4 −2
Original line number Diff line number Diff line
@@ -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))) {

include/linux/intel-iommu.h

+1 −0
Original line number Diff line number Diff line
@@ -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;

};

include/linux/intel-svm.h

+11 −0
Original line number Diff line number Diff line
@@ -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