[PATCH v2 04/12] iommu/vt-d: Use pci_get_domain_bus_and_slot() in pgtable_walk()

From: Lu Baolu
Date: Mon Jun 13 2022 - 23:00:06 EST


Use pci_get_domain_bus_and_slot() instead of searching the global list
to retrieve the pci device pointer. This also removes the global
device_domain_list as there isn't any consumer anymore.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
---
drivers/iommu/intel/iommu.h | 1 -
drivers/iommu/intel/iommu.c | 33 ++++++---------------------------
2 files changed, 6 insertions(+), 28 deletions(-)

diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index 2f4a5b9509c0..6724703d573b 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -609,7 +609,6 @@ struct intel_iommu {
/* PCI domain-device relationship */
struct device_domain_info {
struct list_head link; /* link to domain siblings */
- struct list_head global; /* link to global list */
struct list_head table; /* link to pasid table */
u32 segment; /* PCI segment number */
u8 bus; /* PCI bus number */
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 695aed474e5d..839bb5f3e000 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -131,8 +131,6 @@ static struct intel_iommu **g_iommus;

static void __init check_tylersburg_isoch(void);
static int rwbf_quirk;
-static inline struct device_domain_info *
-dmar_search_domain_by_dev_info(int segment, int bus, int devfn);

/*
* set to 1 to panic kernel if can't successfully enable VT-d
@@ -315,7 +313,6 @@ static int iommu_skip_te_disable;
#define IDENTMAP_AZALIA 4

static DEFINE_SPINLOCK(device_domain_lock);
-static LIST_HEAD(device_domain_list);
const struct iommu_ops intel_iommu_ops;

static bool translation_pre_enabled(struct intel_iommu *iommu)
@@ -845,9 +842,14 @@ static void pgtable_walk(struct intel_iommu *iommu, unsigned long pfn, u8 bus, u
struct device_domain_info *info;
struct dma_pte *parent, *pte;
struct dmar_domain *domain;
+ struct pci_dev *pdev;
int offset, level;

- info = dmar_search_domain_by_dev_info(iommu->segment, bus, devfn);
+ pdev = pci_get_domain_bus_and_slot(iommu->segment, bus, devfn);
+ if (!pdev)
+ return;
+
+ info = dev_iommu_priv_get(&pdev->dev);
if (!info || !info->domain) {
pr_info("device [%02x:%02x.%d] not probed\n",
bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
@@ -2356,19 +2358,6 @@ static void domain_remove_dev_info(struct dmar_domain *domain)
spin_unlock_irqrestore(&device_domain_lock, flags);
}

-static inline struct device_domain_info *
-dmar_search_domain_by_dev_info(int segment, int bus, int devfn)
-{
- struct device_domain_info *info;
-
- list_for_each_entry(info, &device_domain_list, global)
- if (info->segment == segment && info->bus == bus &&
- info->devfn == devfn)
- return info;
-
- return NULL;
-}
-
static int domain_setup_first_level(struct intel_iommu *iommu,
struct dmar_domain *domain,
struct device *dev,
@@ -4572,7 +4561,6 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev)
struct pci_dev *pdev = dev_is_pci(dev) ? to_pci_dev(dev) : NULL;
struct device_domain_info *info;
struct intel_iommu *iommu;
- unsigned long flags;
u8 bus, devfn;

iommu = device_to_iommu(dev, &bus, &devfn);
@@ -4615,10 +4603,7 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev)
}
}

- spin_lock_irqsave(&device_domain_lock, flags);
- list_add(&info->global, &device_domain_list);
dev_iommu_priv_set(dev, info);
- spin_unlock_irqrestore(&device_domain_lock, flags);

return &iommu->iommu;
}
@@ -4626,15 +4611,9 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev)
static void intel_iommu_release_device(struct device *dev)
{
struct device_domain_info *info = dev_iommu_priv_get(dev);
- unsigned long flags;

dmar_remove_one_dev_info(dev);
-
- spin_lock_irqsave(&device_domain_lock, flags);
dev_iommu_priv_set(dev, NULL);
- list_del(&info->global);
- spin_unlock_irqrestore(&device_domain_lock, flags);
-
kfree(info);
set_dma_ops(dev, NULL);
}
--
2.25.1