diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-kernel-iommu_groups | 9 | ||||
| -rw-r--r-- | drivers/iommu/iommu.c | 12 | ||||
| -rw-r--r-- | include/linux/iommu.h | 6 |
3 files changed, 22 insertions, 5 deletions
diff --git a/Documentation/ABI/testing/sysfs-kernel-iommu_groups b/Documentation/ABI/testing/sysfs-kernel-iommu_groups index 35c64e00b35c..017f5bc3920c 100644 --- a/Documentation/ABI/testing/sysfs-kernel-iommu_groups +++ b/Documentation/ABI/testing/sysfs-kernel-iommu_groups @@ -24,3 +24,12 @@ Description: /sys/kernel/iommu_groups/reserved_regions list IOVA region is described on a single line: the 1st field is the base IOVA, the second is the end IOVA and the third field describes the type of the region. + +What: /sys/kernel/iommu_groups/reserved_regions +Date: June 2019 +KernelVersion: v5.3 +Contact: Eric Auger <eric.auger@redhat.com> +Description: In case an RMRR is used only by graphics or USB devices + it is now exposed as "direct-relaxable" instead of "direct". + In device assignment use case, for instance, those RMRR + are considered to be relaxable and safe. diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index ba0661744a3d..46a06ff46e47 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -73,10 +73,11 @@ struct iommu_group_attribute { }; static const char * const iommu_group_resv_type_string[] = { - [IOMMU_RESV_DIRECT] = "direct", - [IOMMU_RESV_RESERVED] = "reserved", - [IOMMU_RESV_MSI] = "msi", - [IOMMU_RESV_SW_MSI] = "msi", + [IOMMU_RESV_DIRECT] = "direct", + [IOMMU_RESV_DIRECT_RELAXABLE] = "direct-relaxable", + [IOMMU_RESV_RESERVED] = "reserved", + [IOMMU_RESV_MSI] = "msi", + [IOMMU_RESV_SW_MSI] = "msi", }; #define IOMMU_GROUP_ATTR(_name, _mode, _show, _store) \ @@ -575,7 +576,8 @@ static int iommu_group_create_direct_mappings(struct iommu_group *group, start = ALIGN(entry->start, pg_size); end = ALIGN(entry->start + entry->length, pg_size); - if (entry->type != IOMMU_RESV_DIRECT) + if (entry->type != IOMMU_RESV_DIRECT && + entry->type != IOMMU_RESV_DIRECT_RELAXABLE) continue; for (addr = start; addr < end; addr += pg_size) { diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 91af22a344e2..ab7a1c85af75 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -135,6 +135,12 @@ enum iommu_attr { enum iommu_resv_type { /* Memory regions which must be mapped 1:1 at all times */ IOMMU_RESV_DIRECT, + /* + * Memory regions which are advertised to be 1:1 but are + * commonly considered relaxable in some conditions, + * for instance in device assignment use case (USB, Graphics) + */ + IOMMU_RESV_DIRECT_RELAXABLE, /* Arbitrary "never map this or give it to a device" address ranges */ IOMMU_RESV_RESERVED, /* Hardware MSI region (untranslated) */ |