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iommu/vt-d: Replace intel SVM APIs with generic SVA APIs

This patch is an initial step to replace Intel SVM code with the following IOMMU SVA ops: intel_svm_bind_mm() => iommu_sva_bind_device() intel_svm_unbind_mm() => iommu_sva_unbind_device() intel_svm_is_pasid_valid() => iommu_sva_get_pasid() The features below will continue to work but are not included in this patch in that they are handled mostly within the IOMMU subsystem. - IO page fault - mmu notifier Consolidation of the above will come after merging generic IOMMU sva code[1]. There should not be any changes needed for SVA users such as accelerator device drivers during this time. [1] http://jpbrucker.net/sva/

Jacob Pan committed 6 years ago

Commit 064a57d1 parent 76fdd6c4 files · +78 −141Browse files

Showing the changes to include/linux (2 of 4 files). Show all

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2 files
  1. include/linux/intel-iommu.h +6 −0
  2. include/linux/intel-svm.h +0 −86
include/linux/intel-iommu.h+6−0
@@ -723,6 +723,10 @@ extern int intel_svm_finish_prq(struct intel_iommu *iommu); · 722 unmodified lines
723723 int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
724724 struct iommu_gpasid_bind_data *data);
725725 int intel_svm_unbind_gpasid(struct device *dev, int pasid);
726+struct iommu_sva *intel_svm_bind(struct device *dev, struct mm_struct *mm,
727+ void *drvdata);
728+void intel_svm_unbind(struct iommu_sva *handle);
729+int intel_svm_get_pasid(struct iommu_sva *handle);
726730 struct svm_dev_ops;
727731
728732 struct intel_svm_dev {
@@ -730,6 +734,8 @@ struct intel_svm_dev { · 1 unmodified line
730734 struct rcu_head rcu;
731735 struct device *dev;
732736 struct svm_dev_ops *ops;
737+ struct iommu_sva sva;
738+ int pasid;
733739 int users;
734740 u16 did;
735741 u16 dev_iotlb:1;
include/linux/intel-svm.h+0−86
@@ -21,7 +21,6 @@ struct svm_dev_ops { · 20 unmodified lines
2121 #define SVM_REQ_EXEC (1<<1)
2222 #define SVM_REQ_PRIV (1<<0)
2323
24−
2524 /*
2625 * The SVM_FLAG_PRIVATE_PASID flag requests a PASID which is *not* the "main"
2726 * PASID for the current process. Even if a PASID already exists, a new one
@@ -57,89 +56,4 @@ struct svm_dev_ops { · 29 unmodified lines
5756 */
5857 #define SVM_FLAG_GUEST_PASID (1<<3)
5958
60−#ifdef CONFIG_INTEL_IOMMU_SVM
61−
62−/**
63− * intel_svm_bind_mm() - Bind the current process to a PASID
64− * @dev: Device to be granted access
65− * @pasid: Address for allocated PASID
66− * @flags: Flags. Later for requesting supervisor mode, etc.
67− * @ops: Callbacks to device driver
68− *
69− * This function attempts to enable PASID support for the given device.
70− * If the @pasid argument is non-%NULL, a PASID is allocated for access
71− * to the MM of the current process.
72− *
73− * By using a %NULL value for the @pasid argument, this function can
74− * be used to simply validate that PASID support is available for the
75− * given device — i.e. that it is behind an IOMMU which has the
76− * requisite support, and is enabled.
77− *
78− * Page faults are handled transparently by the IOMMU code, and there
79− * should be no need for the device driver to be involved. If a page
80− * fault cannot be handled (i.e. is an invalid address rather than
81− * just needs paging in), then the page request will be completed by
82− * the core IOMMU code with appropriate status, and the device itself
83− * can then report the resulting fault to its driver via whatever
84− * mechanism is appropriate.
85− *
86− * Multiple calls from the same process may result in the same PASID
87− * being re-used. A reference count is kept.
88− */
89−extern int intel_svm_bind_mm(struct device *dev, int *pasid, int flags,
90− struct svm_dev_ops *ops);
91−
92−/**
93− * intel_svm_unbind_mm() - Unbind a specified PASID
94− * @dev: Device for which PASID was allocated
95− * @pasid: PASID value to be unbound
96− *
97− * This function allows a PASID to be retired when the device no
98− * longer requires access to the address space of a given process.
99− *
100− * If the use count for the PASID in question reaches zero, the
101− * PASID is revoked and may no longer be used by hardware.
102− *
103− * Device drivers are required to ensure that no access (including
104− * page requests) is currently outstanding for the PASID in question,
105− * before calling this function.
106− */
107−extern int intel_svm_unbind_mm(struct device *dev, int pasid);
108−
109−/**
110− * intel_svm_is_pasid_valid() - check if pasid is valid
111− * @dev: Device for which PASID was allocated
112− * @pasid: PASID value to be checked
113− *
114− * This function checks if the specified pasid is still valid. A
115− * valid pasid means the backing mm is still having a valid user.
116− * For kernel callers init_mm is always valid. for other mm, if mm->mm_users
117− * is non-zero, it is valid.
118− *
119− * returns -EINVAL if invalid pasid, 0 if pasid ref count is invalid
120− * 1 if pasid is valid.
121− */
122−extern int intel_svm_is_pasid_valid(struct device *dev, int pasid);
123−
124−#else /* CONFIG_INTEL_IOMMU_SVM */
125−
126−static inline int intel_svm_bind_mm(struct device *dev, int *pasid,
127− int flags, struct svm_dev_ops *ops)
128−{
129− return -ENOSYS;
130−}
131−
132−static inline int intel_svm_unbind_mm(struct device *dev, int pasid)
133−{
134− BUG();
135−}
136−
137−static inline int intel_svm_is_pasid_valid(struct device *dev, int pasid)
138−{
139− return -EINVAL;
140−}
141−#endif /* CONFIG_INTEL_IOMMU_SVM */
142−
143−#define intel_svm_available(dev) (!intel_svm_bind_mm((dev), NULL, 0, NULL))
144−
14559 #endif /* __INTEL_SVM_H__ */