[PATCH 5/6] iommu: remove IOMMU_DEV_FEAT_AUX

Christoph Hellwig
2021-05-10T06:54:38Z

This feature is entirely unused, and was only ever called by unused code
either.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/iommu/intel/iommu.c | 82 -------------------------------------
drivers/iommu/intel/svm.c | 6 ---
include/linux/intel-iommu.h | 1 -
include/linux/iommu.h | 2 -
4 files changed, 91 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 6cae6e4d693226..2603d95ecb4c0e 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -2573,7 +2573,6 @@ static struct dmar_domain *dmar_insert_one_dev_info(struct intel_iommu *iommu,
info->domain = domain;
info->iommu = iommu;
info->pasid_table = NULL;
- info->auxd_enabled = 0;

if (dev && dev_is_pci(dev)) {
struct pci_dev *pdev = to_pci_dev(info->dev);
@@ -4546,19 +4545,6 @@ static void intel_iommu_domain_free(struct iommu_domain *domain)
domain_exit(to_dmar_domain(domain));
}

-/*
- * Check whether a @domain could be attached to the @dev through the
- * aux-domain attach/detach APIs.
- */
-static inline bool
-is_aux_domain(struct device *dev, struct iommu_domain *domain)
-{
- struct device_domain_info *info = get_domain_info(dev);
-
- return info && info->auxd_enabled &&
- domain->type == IOMMU_DOMAIN_UNMANAGED;
-}
-
static int prepare_domain_attach_device(struct iommu_domain *domain,
struct device *dev)
{
@@ -4612,9 +4598,6 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
return -EPERM;
}

- if (is_aux_domain(dev, domain))
- return -EPERM;
-
/* normally dev is not mapped */
if (unlikely(domain_context_mapped(dev))) {
struct dmar_domain *old_domain;
@@ -5083,52 +5066,9 @@ static struct iommu_group *intel_iommu_device_group(struct device *dev)
return generic_device_group(dev);
}

-static int intel_iommu_enable_auxd(struct device *dev)
-{
- struct device_domain_info *info;
- struct intel_iommu *iommu;
- unsigned long flags;
- int ret;
-
- iommu = device_to_iommu(dev, NULL, NULL);
- if (!iommu || dmar_disabled)
- return -EINVAL;
-
- if (!sm_supported(iommu) || !pasid_supported(iommu))
- return -EINVAL;
-
- ret = intel_iommu_enable_pasid(iommu, dev);
- if (ret)
- return -ENODEV;
-
- spin_lock_irqsave(&device_domain_lock, flags);
- info = get_domain_info(dev);
- info->auxd_enabled = 1;
- spin_unlock_irqrestore(&device_domain_lock, flags);
-
- return 0;
-}
-
-static int intel_iommu_disable_auxd(struct device *dev)
-{
- struct device_domain_info *info;
- unsigned long flags;
-
- spin_lock_irqsave(&device_domain_lock, flags);
- info = get_domain_info(dev);
- if (!WARN_ON(!info))
- info->auxd_enabled = 0;
- spin_unlock_irqrestore(&device_domain_lock, flags);
-
- return 0;
-}
-
static int
intel_iommu_dev_enable_feat(struct device *dev, enum iommu_dev_features feat)
{
- if (feat == IOMMU_DEV_FEAT_AUX)
- return intel_iommu_enable_auxd(dev);
-
if (feat == IOMMU_DEV_FEAT_IOPF) {
struct device_domain_info *info = get_domain_info(dev);

@@ -5152,26 +5092,6 @@ intel_iommu_dev_enable_feat(struct device *dev, enum iommu_dev_features feat)
return -ENODEV;
}

-static int
-intel_iommu_dev_disable_feat(struct device *dev, enum iommu_dev_features feat)
-{
- if (feat == IOMMU_DEV_FEAT_AUX)
- return intel_iommu_disable_auxd(dev);
-
- return -ENODEV;
-}
-
-static bool
-intel_iommu_dev_feat_enabled(struct device *dev, enum iommu_dev_features feat)
-{
- struct device_domain_info *info = get_domain_info(dev);
-
- if (feat == IOMMU_DEV_FEAT_AUX)
- return scalable_mode_support() && info && info->auxd_enabled;
-
- return false;
-}
-
static bool intel_iommu_is_attach_deferred(struct iommu_domain *domain,
struct device *dev)
{
@@ -5283,9 +5203,7 @@ const struct iommu_ops intel_iommu_ops = {
.get_resv_regions = intel_iommu_get_resv_regions,
.put_resv_regions = generic_iommu_put_resv_regions,
.device_group = intel_iommu_device_group,
- .dev_feat_enabled = intel_iommu_dev_feat_enabled,
.dev_enable_feat = intel_iommu_dev_enable_feat,
- .dev_disable_feat = intel_iommu_dev_disable_feat,
.is_attach_deferred = intel_iommu_is_attach_deferred,
.def_domain_type = device_def_domain_type,
.pgsize_bitmap = INTEL_IOMMU_PGSIZES,
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 5165cea904211a..54b55f867438c8 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -347,10 +347,6 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
sdev->sid = PCI_DEVID(info->bus, info->devfn);
sdev->iommu = iommu;

- /* Only count users if device has aux domains */
- if (iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX))
- sdev->users = 1;
-
/* Set up device context entry for PASID if not enabled already */
ret = intel_iommu_enable_pasid(iommu, sdev->dev);
if (ret) {
@@ -412,8 +408,6 @@ int intel_svm_unbind_gpasid(struct device *dev, u32 pasid)
goto out;

if (sdev) {
- if (iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX))
- sdev->users--;
if (!sdev->users) {
list_del_rcu(&sdev->list);
intel_pasid_tear_down_entry(iommu, dev,
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index c12b8e6545733c..4b855c42435f7c 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -636,7 +636,6 @@ struct device_domain_info {
u8 pri_enabled:1;
u8 ats_supported:1;
u8 ats_enabled:1;
- u8 auxd_enabled:1; /* Multiple domains per device */
u8 ats_qdep;
struct device *dev; /* it's NULL for PCIe-to-PCI bridge */
struct intel_iommu *iommu; /* IOMMU used by this device */
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index b0bf99dfd80d16..ef9e7dcef76e90 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -132,7 +132,6 @@ struct iommu_resv_region {

/**
* 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
@@ -144,7 +143,6 @@ struct iommu_resv_region {
* Device drivers enable a feature using iommu_dev_enable_feature().
*/
enum iommu_dev_features {
- IOMMU_DEV_FEAT_AUX,
IOMMU_DEV_FEAT_SVA,
IOMMU_DEV_FEAT_IOPF,
};
--
2.30.2