From 4de354ec2f0c0529980ea4aa9fc4f35b296d3de8 Mon Sep 17 00:00:00 2001
From: Lu Baolu <baolu.lu@linux.intel.com>
Date: Sat, 25 May 2019 13:41:27 +0800
Subject: [PATCH] iommu/vt-d: Delegate the identity domain to upper layer
This allows the iommu generic layer to allocate an identity domain
and attach it to a device. Hence, the identity domain is delegated
to upper layer. As a side effect, iommu_identity_mapping can't be
used to check the existence of identity domains any more.
Signed-off-by: James Sewart <jamessewart@arista.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
drivers/iommu/intel-iommu.c | 90 ++++++++++++++++++++++++-------------
1 file changed, 58 insertions(+), 32 deletions(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 9db0f7f7f1e2a..dc7d376a03aa4 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -350,6 +350,7 @@ static void domain_context_clear(struct intel_iommu *iommu,
struct device *dev);
static int domain_detach_iommu(struct dmar_domain *domain,
struct intel_iommu *iommu);
+static bool device_is_rmrr_locked(struct device *dev);
#ifdef CONFIG_INTEL_IOMMU_DEFAULT_ON
int dmar_disabled = 0;
@@ -2808,7 +2809,9 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width);
static int __init si_domain_init(int hw)
{
- int nid, ret;
+ struct dmar_rmrr_unit *rmrr;
+ struct device *dev;
+ int i, nid, ret;
si_domain = alloc_domain(DOMAIN_FLAG_STATIC_IDENTITY);
if (!si_domain)
@@ -2819,8 +2822,6 @@ static int __init si_domain_init(int hw)
return -EFAULT;
}
- pr_debug("Identity mapping domain allocated\n");
-
if (hw)
return 0;
@@ -2836,6 +2837,31 @@ static int __init si_domain_init(int hw)
}
}
+ /*
+ * Normally we use DMA domains for devices which have RMRRs. But we
+ * loose this requirement for graphic and usb devices. Identity map
+ * the RMRRs for graphic and USB devices so that they could use the
+ * si_domain.
+ */
+ for_each_rmrr_units(rmrr) {
+ for_each_active_dev_scope(rmrr->devices, rmrr->devices_cnt,
+ i, dev) {
+ unsigned long long start = rmrr->base_address;
+ unsigned long long end = rmrr->end_address;
+
+ if (device_is_rmrr_locked(dev))
+ continue;
+
+ if (WARN_ON(end < start ||
+ end >> agaw_to_width(si_domain->agaw)))
+ continue;
+
+ ret = iommu_domain_identity_map(si_domain, start, end);
+ if (ret)
+ return ret;
+ }
+ }
+
return 0;
}
@@ -2843,9 +2869,6 @@ static int identity_mapping(struct device *dev)
{
struct device_domain_info *info;
- if (likely(!iommu_identity_mapping))
- return 0;
-
info = dev->archdata.iommu;
if (info && info != DUMMY_DEVICE_DOMAIN_INFO)
return (info->domain == si_domain);
@@ -3431,11 +3454,9 @@ static int __init init_dmars(void)
check_tylersburg_isoch();
- if (iommu_identity_mapping) {
- ret = si_domain_init(hw_pass_through);
- if (ret)
- goto free_iommu;
- }
+ ret = si_domain_init(hw_pass_through);
+ if (ret)
+ goto free_iommu;
/*
@@ -3628,9 +3649,6 @@ static bool iommu_need_mapping(struct device *dev)
if (iommu_dummy(dev))
return false;
- if (!iommu_identity_mapping)
- return true;
-
found = identity_mapping(dev);
if (found) {
if (iommu_should_identity_map(dev, 0))
@@ -5051,32 +5069,40 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type)
struct dmar_domain *dmar_domain;
struct iommu_domain *domain;
- if (type != IOMMU_DOMAIN_UNMANAGED)
- return NULL;
+ switch (type) {
+ case IOMMU_DOMAIN_UNMANAGED:
+ dmar_domain = alloc_domain(DOMAIN_FLAG_VIRTUAL_MACHINE);
+ if (!dmar_domain) {
+ pr_err("Can't allocate dmar_domain\n");
+ return NULL;
+ }
+ if (md_domain_init(dmar_domain, DEFAULT_DOMAIN_ADDRESS_WIDTH)) {
+ pr_err("Domain initialization failed\n");
+ domain_exit(dmar_domain);
+ return NULL;
+ }
+ domain_update_iommu_cap(dmar_domain);
- dmar_domain = alloc_domain(DOMAIN_FLAG_VIRTUAL_MACHINE);
- if (!dmar_domain) {
- pr_err("Can't allocate dmar_domain\n");
- return NULL;
- }
- if (md_domain_init(dmar_domain, DEFAULT_DOMAIN_ADDRESS_WIDTH)) {
- pr_err("Domain initialization failed\n");
- domain_exit(dmar_domain);
+ domain = &dmar_domain->domain;
+ domain->geometry.aperture_start = 0;
+ domain->geometry.aperture_end =
+ __DOMAIN_MAX_ADDR(dmar_domain->gaw);
+ domain->geometry.force_aperture = true;
+
+ return domain;
+ case IOMMU_DOMAIN_IDENTITY:
+ return &si_domain->domain;
+ default:
return NULL;
}
- domain_update_iommu_cap(dmar_domain);
-
- domain = &dmar_domain->domain;
- domain->geometry.aperture_start = 0;
- domain->geometry.aperture_end = __DOMAIN_MAX_ADDR(dmar_domain->gaw);
- domain->geometry.force_aperture = true;
- return domain;
+ return NULL;
}
static void intel_iommu_domain_free(struct iommu_domain *domain)
{
- domain_exit(to_dmar_domain(domain));
+ if (domain != &si_domain->domain)
+ domain_exit(to_dmar_domain(domain));
}
/*
--
2.30.2