iommu/amd: Reserve exclusion range in iova-domain

If a device has an exclusion range specified in the IVRS
table, this region needs to be reserved in the iova-domain
of that device. This hasn't happened until now and can cause
data corruption on data transfered with these devices.

Treat exclusion ranges as reserved regions in the iommu-core
to fix the problem.

Fixes: be2a022c0dd0 ('x86, AMD IOMMU: add functions to parse IOMMU memory mapping requirements for devices')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Gary R Hook <gary.hook@amd.com>

3 files changed, 12 insertions, 6 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 21cb088d6687..f7cdd2ab7f11 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3169,21 +3169,24 @@ static void amd_iommu_get_resv_regions(struct device *dev,
                 return;
 
         list_for_each_entry(entry, &amd_iommu_unity_map, list) {
+                int type, prot = 0;
                 size_t length;
-                int prot = 0;
 
                 if (devid < entry->devid_start || devid > entry->devid_end)
                         continue;
 
+                type   = IOMMU_RESV_DIRECT;
                 length = entry->address_end - entry->address_start;
                 if (entry->prot & IOMMU_PROT_IR)
                         prot |= IOMMU_READ;
                 if (entry->prot & IOMMU_PROT_IW)
                         prot |= IOMMU_WRITE;
+                if (entry->prot & IOMMU_UNITY_MAP_FLAG_EXCL_RANGE)
+                        /* Exclusion range */
+                        type = IOMMU_RESV_RESERVED;
 
                 region = iommu_alloc_resv_region(entry->address_start,
-                                                 length, prot,
-                                                 IOMMU_RESV_DIRECT);
+                                                 length, prot, type);
                 if (!region) {
                         dev_err(dev, "Out of memory allocating dm-regions\n");
                         return;
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index f773792d77fd..1b1378619fc9 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -2013,6 +2013,9 @@ static int __init init_unity_map_range(struct ivmd_header *m)
         if (e == NULL)
                 return -ENOMEM;
 
+        if (m->flags & IVMD_FLAG_EXCL_RANGE)
+                init_exclusion_range(m);
+
         switch (m->type) {
         default:
                 kfree(e);
@@ -2059,9 +2062,7 @@ static int __init init_memory_definitions(struct acpi_table_header *table)
 
         while (p < end) {
                 m = (struct ivmd_header *)p;
-                if (m->flags & IVMD_FLAG_EXCL_RANGE)
-                        init_exclusion_range(m);
-                else if (m->flags & IVMD_FLAG_UNITY_MAP)
+                if (m->flags & (IVMD_FLAG_UNITY_MAP | IVMD_FLAG_EXCL_RANGE))
                         init_unity_map_range(m);
 
                 p += m->length;
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index eae0741f72dc..87965e4d9647 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -374,6 +374,8 @@
 #define IOMMU_PROT_IR 0x01
 #define IOMMU_PROT_IW 0x02
 
+#define IOMMU_UNITY_MAP_FLAG_EXCL_RANGE (1 << 2)
+
 /* IOMMU capabilities */
 #define IOMMU_CAP_IOTLB   24
 #define IOMMU_CAP_NPCACHE 26