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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
723int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,723int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
724 struct iommu_gpasid_bind_data *data);724 struct iommu_gpasid_bind_data *data);
725int intel_svm_unbind_gpasid(struct device *dev, int pasid);725int intel_svm_unbind_gpasid(struct device *dev, int pasid);
726struct iommu_sva *intel_svm_bind(struct device *dev, struct mm_struct *mm,
727 void *drvdata);
728void intel_svm_unbind(struct iommu_sva *handle);
729int intel_svm_get_pasid(struct iommu_sva *handle);
726struct svm_dev_ops;730struct svm_dev_ops;
727 731
728struct intel_svm_dev {732struct intel_svm_dev {
@@ -730,6 +734,8 @@ struct intel_svm_dev { · 1 unmodified line
730 struct rcu_head rcu;734 struct rcu_head rcu;
731 struct device *dev;735 struct device *dev;
732 struct svm_dev_ops *ops;736 struct svm_dev_ops *ops;
737 struct iommu_sva sva;
738 int pasid;
733 int users;739 int users;
734 u16 did;740 u16 did;
735 u16 dev_iotlb:1;741 u16 dev_iotlb:1;
include/linux/intel-svm.h+0−86
@@ -21,7 +21,6 @@ struct svm_dev_ops { · 20 unmodified lines
21#define SVM_REQ_EXEC (1<<1)21#define SVM_REQ_EXEC (1<<1)
22#define SVM_REQ_PRIV (1<<0)22#define SVM_REQ_PRIV (1<<0)
23 23
24
25/*24/*
26 * The SVM_FLAG_PRIVATE_PASID flag requests a PASID which is *not* the "main"25 * The SVM_FLAG_PRIVATE_PASID flag requests a PASID which is *not* the "main"
27 * PASID for the current process. Even if a PASID already exists, a new one26 * 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
57 */56 */
58#define SVM_FLAG_GUEST_PASID (1<<3)57#define SVM_FLAG_GUEST_PASID (1<<3)
59 58
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 */
89extern 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 */
107extern 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 */
122extern int intel_svm_is_pasid_valid(struct device *dev, int pasid);
123
124#else /* CONFIG_INTEL_IOMMU_SVM */
125
126static 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
132static inline int intel_svm_unbind_mm(struct device *dev, int pasid)
133{
134 BUG();
135}
136
137static 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
145#endif /* __INTEL_SVM_H__ */59#endif /* __INTEL_SVM_H__ */