1 files changed, 179 insertions, 0 deletions

diff --git a/drivers/iommu/intel-pasid.c b/drivers/iommu/intel-pasid.c
index e918fe01ce7f..fe95c9bd4d33 100644
--- a/drivers/iommu/intel-pasid.c
+++ b/drivers/iommu/intel-pasid.c
@@ -13,6 +13,8 @@
 #include <linux/intel-iommu.h>
 #include <linux/iommu.h>
 #include <linux/memory.h>
+#include <linux/pci.h>
+#include <linux/pci-ats.h>
 #include <linux/spinlock.h>
 
 #include "intel-pasid.h"
@@ -58,3 +60,180 @@ void *intel_pasid_lookup_id(int pasid)
 
 	return p;
 }
+
+/*
+ * Per device pasid table management:
+ */
+static inline void
+device_attach_pasid_table(struct device_domain_info *info,
+			  struct pasid_table *pasid_table)
+{
+	info->pasid_table = pasid_table;
+	list_add(&info->table, &pasid_table->dev);
+}
+
+static inline void
+device_detach_pasid_table(struct device_domain_info *info,
+			  struct pasid_table *pasid_table)
+{
+	info->pasid_table = NULL;
+	list_del(&info->table);
+}
+
+struct pasid_table_opaque {
+	struct pasid_table	**pasid_table;
+	int			segment;
+	int			bus;
+	int			devfn;
+};
+
+static int search_pasid_table(struct device_domain_info *info, void *opaque)
+{
+	struct pasid_table_opaque *data = opaque;
+
+	if (info->iommu->segment == data->segment &&
+	    info->bus == data->bus &&
+	    info->devfn == data->devfn &&
+	    info->pasid_table) {
+		*data->pasid_table = info->pasid_table;
+		return 1;
+	}
+
+	return 0;
+}
+
+static int get_alias_pasid_table(struct pci_dev *pdev, u16 alias, void *opaque)
+{
+	struct pasid_table_opaque *data = opaque;
+
+	data->segment = pci_domain_nr(pdev->bus);
+	data->bus = PCI_BUS_NUM(alias);
+	data->devfn = alias & 0xff;
+
+	return for_each_device_domain(&search_pasid_table, data);
+}
+
+/*
+ * Allocate a pasid table for @dev. It should be called in a
+ * single-thread context.
+ */
+int intel_pasid_alloc_table(struct device *dev)
+{
+	struct device_domain_info *info;
+	struct pasid_table *pasid_table;
+	struct pasid_table_opaque data;
+	struct page *pages;
+	size_t size, count;
+	int ret, order;
+
+	info = dev->archdata.iommu;
+	if (WARN_ON(!info || !dev_is_pci(dev) ||
+		    !info->pasid_supported || info->pasid_table))
+		return -EINVAL;
+
+	/* DMA alias device already has a pasid table, use it: */
+	data.pasid_table = &pasid_table;
+	ret = pci_for_each_dma_alias(to_pci_dev(dev),
+				     &get_alias_pasid_table, &data);
+	if (ret)
+		goto attach_out;
+
+	pasid_table = kzalloc(sizeof(*pasid_table), GFP_ATOMIC);
+	if (!pasid_table)
+		return -ENOMEM;
+	INIT_LIST_HEAD(&pasid_table->dev);
+
+	size = sizeof(struct pasid_entry);
+	count = min_t(int, pci_max_pasids(to_pci_dev(dev)), intel_pasid_max_id);
+	order = get_order(size * count);
+	pages = alloc_pages_node(info->iommu->node,
+				 GFP_ATOMIC | __GFP_ZERO,
+				 order);
+	if (!pages)
+		return -ENOMEM;
+
+	pasid_table->table = page_address(pages);
+	pasid_table->order = order;
+	pasid_table->max_pasid = count;
+
+attach_out:
+	device_attach_pasid_table(info, pasid_table);
+
+	return 0;
+}
+
+void intel_pasid_free_table(struct device *dev)
+{
+	struct device_domain_info *info;
+	struct pasid_table *pasid_table;
+
+	info = dev->archdata.iommu;
+	if (!info || !dev_is_pci(dev) ||
+	    !info->pasid_supported || !info->pasid_table)
+		return;
+
+	pasid_table = info->pasid_table;
+	device_detach_pasid_table(info, pasid_table);
+
+	if (!list_empty(&pasid_table->dev))
+		return;
+
+	free_pages((unsigned long)pasid_table->table, pasid_table->order);
+	kfree(pasid_table);
+}
+
+struct pasid_table *intel_pasid_get_table(struct device *dev)
+{
+	struct device_domain_info *info;
+
+	info = dev->archdata.iommu;
+	if (!info)
+		return NULL;
+
+	return info->pasid_table;
+}
+
+int intel_pasid_get_dev_max_id(struct device *dev)
+{
+	struct device_domain_info *info;
+
+	info = dev->archdata.iommu;
+	if (!info || !info->pasid_table)
+		return 0;
+
+	return info->pasid_table->max_pasid;
+}
+
+struct pasid_entry *intel_pasid_get_entry(struct device *dev, int pasid)
+{
+	struct pasid_table *pasid_table;
+	struct pasid_entry *entries;
+
+	pasid_table = intel_pasid_get_table(dev);
+	if (WARN_ON(!pasid_table || pasid < 0 ||
+		    pasid >= intel_pasid_get_dev_max_id(dev)))
+		return NULL;
+
+	entries = pasid_table->table;
+
+	return &entries[pasid];
+}
+
+/*
+ * Interfaces for PASID table entry manipulation:
+ */
+static inline void pasid_clear_entry(struct pasid_entry *pe)
+{
+	WRITE_ONCE(pe->val, 0);
+}
+
+void intel_pasid_clear_entry(struct device *dev, int pasid)
+{
+	struct pasid_entry *pe;
+
+	pe = intel_pasid_get_entry(dev, pasid);
+	if (WARN_ON(!pe))
+		return;
+
+	pasid_clear_entry(pe);
+}