diff options
| author | Jean-Philippe Brucker <jean-philippe@linaro.org> | 2021-04-01 17:47:12 +0200 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2021-04-07 10:54:28 +0200 |
| commit | 34b48c704d194738eef0893aa06e412bdc8a972f (patch) | |
| tree | 1dda798acf14d87c1f3358c6202e5311158eba13 /include/linux/iommu.h | |
| parent | 434b73e61cc65cdd26618af6fa4736c2ba1eb29b (diff) | |
iommu: Separate IOMMU_DEV_FEAT_IOPF from IOMMU_DEV_FEAT_SVA
Some devices manage I/O Page Faults (IOPF) themselves instead of relying
on PCIe PRI or Arm SMMU stall. Allow their drivers to enable SVA without
mandating IOMMU-managed IOPF. The other device drivers now need to first
enable IOMMU_DEV_FEAT_IOPF before enabling IOMMU_DEV_FEAT_SVA. Enabling
IOMMU_DEV_FEAT_IOPF on its own doesn't have any effect visible to the
device driver, it is used in combination with other features.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20210401154718.307519-4-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'include/linux/iommu.h')
| -rw-r--r-- | include/linux/iommu.h | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 16ce75693d83..45c4eb372f56 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -156,10 +156,24 @@ struct iommu_resv_region { enum iommu_resv_type type; }; -/* Per device IOMMU features */ +/** + * enum iommu_dev_features - Per device IOMMU features + * @IOMMU_DEV_FEAT_AUX: Auxiliary domain feature + * @IOMMU_DEV_FEAT_SVA: Shared Virtual Addresses + * @IOMMU_DEV_FEAT_IOPF: I/O Page Faults such as PRI or Stall. Generally + * enabling %IOMMU_DEV_FEAT_SVA requires + * %IOMMU_DEV_FEAT_IOPF, but some devices manage I/O Page + * Faults themselves instead of relying on the IOMMU. When + * supported, this feature must be enabled before and + * disabled after %IOMMU_DEV_FEAT_SVA. + * + * Device drivers query whether a feature is supported using + * iommu_dev_has_feature(), and enable it using iommu_dev_enable_feature(). + */ enum iommu_dev_features { - IOMMU_DEV_FEAT_AUX, /* Aux-domain feature */ - IOMMU_DEV_FEAT_SVA, /* Shared Virtual Addresses */ + IOMMU_DEV_FEAT_AUX, + IOMMU_DEV_FEAT_SVA, + IOMMU_DEV_FEAT_IOPF, }; #define IOMMU_PASID_INVALID (-1U) |