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-rw-r--r--include/linux/iommu.h76
1 files changed, 66 insertions, 10 deletions
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 9940319d6f9d..432acc4c054d 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -25,15 +25,29 @@
#define IOMMU_WRITE (2)
#define IOMMU_CACHE (4) /* DMA cache coherency */
+struct iommu_ops;
+struct bus_type;
struct device;
+struct iommu_domain;
+
+/* iommu fault flags */
+#define IOMMU_FAULT_READ 0x0
+#define IOMMU_FAULT_WRITE 0x1
+
+typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
+ struct device *, unsigned long, int);
struct iommu_domain {
+ struct iommu_ops *ops;
void *priv;
+ iommu_fault_handler_t handler;
};
#define IOMMU_CAP_CACHE_COHERENCY 0x1
#define IOMMU_CAP_INTR_REMAP 0x2 /* isolates device intrs */
+#ifdef CONFIG_IOMMU_API
+
struct iommu_ops {
int (*domain_init)(struct iommu_domain *domain);
void (*domain_destroy)(struct iommu_domain *domain);
@@ -49,11 +63,9 @@ struct iommu_ops {
unsigned long cap);
};
-#ifdef CONFIG_IOMMU_API
-
-extern void register_iommu(struct iommu_ops *ops);
-extern bool iommu_found(void);
-extern struct iommu_domain *iommu_domain_alloc(void);
+extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
+extern bool iommu_present(struct bus_type *bus);
+extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
extern void iommu_domain_free(struct iommu_domain *domain);
extern int iommu_attach_device(struct iommu_domain *domain,
struct device *dev);
@@ -67,19 +79,58 @@ extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
unsigned long iova);
extern int iommu_domain_has_cap(struct iommu_domain *domain,
unsigned long cap);
+extern void iommu_set_fault_handler(struct iommu_domain *domain,
+ iommu_fault_handler_t handler);
+
+/**
+ * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
+ * @domain: the iommu domain where the fault has happened
+ * @dev: the device where the fault has happened
+ * @iova: the faulting address
+ * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
+ *
+ * This function should be called by the low-level IOMMU implementations
+ * whenever IOMMU faults happen, to allow high-level users, that are
+ * interested in such events, to know about them.
+ *
+ * This event may be useful for several possible use cases:
+ * - mere logging of the event
+ * - dynamic TLB/PTE loading
+ * - if restarting of the faulting device is required
+ *
+ * Returns 0 on success and an appropriate error code otherwise (if dynamic
+ * PTE/TLB loading will one day be supported, implementations will be able
+ * to tell whether it succeeded or not according to this return value).
+ *
+ * Specifically, -ENOSYS is returned if a fault handler isn't installed
+ * (though fault handlers can also return -ENOSYS, in case they want to
+ * elicit the default behavior of the IOMMU drivers).
+ */
+static inline int report_iommu_fault(struct iommu_domain *domain,
+ struct device *dev, unsigned long iova, int flags)
+{
+ int ret = -ENOSYS;
-#else /* CONFIG_IOMMU_API */
+ /*
+ * if upper layers showed interest and installed a fault handler,
+ * invoke it.
+ */
+ if (domain->handler)
+ ret = domain->handler(domain, dev, iova, flags);
-static inline void register_iommu(struct iommu_ops *ops)
-{
+ return ret;
}
-static inline bool iommu_found(void)
+#else /* CONFIG_IOMMU_API */
+
+struct iommu_ops {};
+
+static inline bool iommu_present(struct bus_type *bus)
{
return false;
}
-static inline struct iommu_domain *iommu_domain_alloc(void)
+static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
{
return NULL;
}
@@ -123,6 +174,11 @@ static inline int domain_has_cap(struct iommu_domain *domain,
return 0;
}
+static inline void iommu_set_fault_handler(struct iommu_domain *domain,
+ iommu_fault_handler_t handler)
+{
+}
+
#endif /* CONFIG_IOMMU_API */
#endif /* __LINUX_IOMMU_H */