From: Jérôme Glisse <jglisse@xxxxxxxxxx>
New user of iommu can share the same mapping for device in same domain.
Which allow saving resources. For this a new iommu domain callback is
needed. This add the core support for the callback.
Signed-off-by: Jérôme Glisse <jglisse@xxxxxxxxxx>
---
include/linux/iommu.h | 145 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 145 insertions(+)
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 20f9a52..ff6983f 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -97,6 +97,9 @@ enum iommu_attr {
* @domain_has_cap: domain capabilities query
* @add_device: add device to iommu grouping
* @remove_device: remove device from iommu grouping
+ * @domain_map_directory: Map a directory of pages.
+ * @domain_update_directory: Update a directory of pages mapping.
+ * @domain_unmap_directory: Unmap a directory of pages.
* @domain_get_attr: Query domain attributes
* @domain_set_attr: Change domain attributes
* @pgsize_bitmap: bitmap of supported page sizes
@@ -130,6 +133,26 @@ struct iommu_ops {
/* Get the numer of window per domain */
u32 (*domain_get_windows)(struct iommu_domain *domain);
+ int (*domain_map_directory)(struct iommu_domain *domain,
+ unsigned long npages,
+ unsigned long *pfns,
+ unsigned long pfn_mask,
+ unsigned long pfn_shift,
+ unsigned long pfn_valid,
+ unsigned long pfn_write,
+ dma_addr_t *iova_base);
+ int (*domain_update_directory)(struct iommu_domain *domain,
+ unsigned long npages,
+ unsigned long *pfns,
+ unsigned long pfn_mask,
+ unsigned long pfn_shift,
+ unsigned long pfn_valid,
+ unsigned long pfn_write,
+ dma_addr_t iova_base);
+ int (*domain_unmap_directory)(struct iommu_domain *domain,
+ unsigned long npages,
+ dma_addr_t iova);
+
unsigned long pgsize_bitmap;
};
@@ -240,6 +263,97 @@ static inline int report_iommu_fault(struct iommu_domain *domain,
return ret;
}
+/* iommu_domain_map_directory() - Map a directory of pages into a given domain.
+ *
+ * @domain: Domain into which mapping should happen.
+ * @npages: The maximum number of page to map.
+ * @pfns: The pfns directory array.
+ * @pfn_mask: The pfn mask (pfn_for_i = (pfns[i] & pfn_mask) >> pfn_shift).
+ * @pfn_shift: The pfn shift (pfn_for_i = (pfns[i] & pfn_mask) >> pfn_shift).
+ * @pfn_valid: An entry in the array is valid if (pfns[i] & pfn_valid).
+ * @pfn_write: An entry should be mapped write if (pfns[i] & pfn_write)
+ * @iova_base: Base io virtual address at which directory is mapped on success.
+ * Returns: Number of mapped pages on success, negative errno otherwise.
+ *
+ * This allow to map contiguously a directory of pages into a specific domain.
+ * On success it sets the base io virtual address at which the directory is
+ * mapped and it returns the number of page successfully mapped. Each entry in
+ * the directory can either be a valid page in read only or in read and write
+ * depending on flags and there can be gaps.
+ */
+static inline int iommu_domain_map_directory(struct iommu_domain *domain,
+ unsigned long npages,
+ unsigned long *pfns,
+ unsigned long pfn_mask,
+ unsigned long pfn_shift,
+ unsigned long pfn_valid,
+ unsigned long pfn_write,
+ dma_addr_t *iova_base)
+{
+ if (!domain->ops->domain_map_directory)
+ return -EINVAL;
+ return domain->ops->domain_map_directory(domain, npages, pfns,
+ pfn_mask, pfn_shift,
+ pfn_valid, pfn_write,
+ iova_base);
+}
+
+/* iommu_domain_update_directory() - Update a directory mapping of pages.
+ *
+ * @domain: Domain into which mapping exist.
+ * @npages: The maximum number of page to map.
+ * @pfns: The pfns directory array.
+ * @pfn_mask: The pfn mask (pfn_for_i = (pfns[i] & pfn_mask) >> pfn_shift).
+ * @pfn_shift: The pfn shift (pfn_for_i = (pfns[i] & pfn_mask) >> pfn_shift).
+ * @pfn_valid: An entry in the array is valid if (pfns[i] & pfn_valid).
+ * @pfn_write: An entry should be mapped write if (pfns[i] & pfn_write)
+ * @iova_base: Base io virtual address at which directory is mapped.
+ * Returns: Number of mapped (positive) or unmapped (negative) pages.
+ *
+ * This allow to update a previously successfull directory mapping of pages,
+ * either by adding or removing or replacing pages or modifying page mapping
+ * (read only to read and write or read and write to read only). It returns
+ * the number of new or removed mapping. Modified mapping are not counted.
+ * So if return value is positive it means there is an increase in the number
+ * of valid mapped entry. If it is negative it means there is a decrease in
+ * the number of valid mapped entry. In all case |return| <= npages.
+ */
+static inline int iommu_domain_update_directory(struct iommu_domain *domain,
+ unsigned long npages,
+ unsigned long *pfns,
+ unsigned long pfn_mask,
+ unsigned long pfn_shift,
+ unsigned long pfn_valid,
+ unsigned long pfn_write,
+ dma_addr_t iova_base)
+{
+ if (!domain->ops->domain_update_directory)
+ return -EINVAL;
+ return domain->ops->domain_update_directory(domain, npages, pfns,
+ pfn_mask, pfn_shift,
+ pfn_valid, pfn_write,
+ iova_base);
+}
+
+/* iommu_domain_unmap_directory() - Unmap a directory of pages in a domain.
+ *
+ * @domain: Domain into which mapping should happen.
+ * @npages: The maximum number of page to map.
+ * @iova_base: Base io virtual address at which directory is mapped.
+ * Returns: Number of unmapped pages.
+ *
+ * This allow to unmap a previously successfull directory mapping of pages. It
+ * free the iova and return the number of valid unmapped entries.
+ */
+static inline int iommu_domain_unmap_directory(struct iommu_domain *domain,
+ unsigned long npages,
+ dma_addr_t iova_base)
+{
+ if (!domain->ops->domain_unmap_directory)
+ return 0;
+ return domain->ops->domain_unmap_directory(domain, npages, iova_base);
+}
+
#else /* CONFIG_IOMMU_API */
struct iommu_ops {};
@@ -424,6 +538,37 @@ static inline void iommu_device_unlink(struct device *dev, struct device *link)
{
}
+static inline int iommu_domain_map_directory(struct iommu_domain *domain,
+ unsigned long npages,
+ unsigned long *pfns,
+ unsigned long pfn_mask,
+ unsigned long pfn_shift,
+ unsigned long pfn_valid,
+ unsigned long pfn_write,
+ dma_addr_t *iova_base)
+{
+ return -EINVAL;
+}
+
+static inline int iommu_domain_update_directory(struct iommu_domain *domain,
+ unsigned long npages,
+ unsigned long *pfns,
+ unsigned long pfn_mask,
+ unsigned long pfn_shift,
+ unsigned long pfn_valid,
+ unsigned long pfn_write,
+ dma_addr_t iova_base)
+{
+ return -EINVAL;
+}
+
+static inline void iommu_domain_unmap_directory(struct iommu_domain *domain,
+ unsigned long npages,
+ dma_addr_t iova_base)
+{
+ return;
+}
+
#endif /* CONFIG_IOMMU_API */
#endif /* __LINUX_IOMMU_H */
--
1.9.3
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