[PATCH 27/34] x86/amd-iommu: Use dev->arch->iommu to store iommu related information

From: Joerg Roedel
Date: Fri Nov 27 2009 - 08:56:58 EST


This patch changes IOMMU code to use dev->archdata->iommu to
store information about the alias device and the domain the
device is attached to.
This allows the driver to get rid of the amd_iommu_pd_table
in the future.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
arch/x86/include/asm/amd_iommu_types.h | 8 +++
arch/x86/include/asm/device.h | 2 +-
arch/x86/kernel/amd_iommu.c | 109 +++++++++++++++++++++++++-------
3 files changed, 95 insertions(+), 24 deletions(-)

diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h
index 02b6a0f..9eaa27b 100644
--- a/arch/x86/include/asm/amd_iommu_types.h
+++ b/arch/x86/include/asm/amd_iommu_types.h
@@ -248,6 +248,14 @@ struct protection_domain {
};

/*
+ * This struct contains device specific data for the IOMMU
+ */
+struct iommu_dev_data {
+ struct device *alias; /* The Alias Device */
+ struct protection_domain *domain; /* Domain the device is bound to */
+};
+
+/*
* For dynamic growth the aperture size is split into ranges of 128MB of
* DMA address space each. This struct represents one such range.
*/
diff --git a/arch/x86/include/asm/device.h b/arch/x86/include/asm/device.h
index cee34e9..029f230 100644
--- a/arch/x86/include/asm/device.h
+++ b/arch/x86/include/asm/device.h
@@ -8,7 +8,7 @@ struct dev_archdata {
#ifdef CONFIG_X86_64
struct dma_map_ops *dma_ops;
#endif
-#ifdef CONFIG_DMAR
+#if defined(CONFIG_DMAR) || defined(CONFIG_AMD_IOMMU)
void *iommu; /* hook for IOMMU specific extension */
#endif
};
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index ed58a16..3214e88 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -73,6 +73,11 @@ static inline u16 get_device_id(struct device *dev)
return calc_devid(pdev->bus->number, pdev->devfn);
}

+static struct iommu_dev_data *get_dev_data(struct device *dev)
+{
+ return dev->archdata.iommu;
+}
+
/*
* In this function the list of preallocated protection domains is traversed to
* find the domain for a specific device
@@ -128,6 +133,35 @@ static bool check_device(struct device *dev)
return true;
}

+static int iommu_init_device(struct device *dev)
+{
+ struct iommu_dev_data *dev_data;
+ struct pci_dev *pdev;
+ u16 devid, alias;
+
+ if (dev->archdata.iommu)
+ return 0;
+
+ dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL);
+ if (!dev_data)
+ return -ENOMEM;
+
+ devid = get_device_id(dev);
+ alias = amd_iommu_alias_table[devid];
+ pdev = pci_get_bus_and_slot(PCI_BUS(alias), alias & 0xff);
+ if (pdev)
+ dev_data->alias = &pdev->dev;
+
+ dev->archdata.iommu = dev_data;
+
+
+ return 0;
+}
+
+static void iommu_uninit_device(struct device *dev)
+{
+ kfree(dev->archdata.iommu);
+}
#ifdef CONFIG_AMD_IOMMU_STATS

/*
@@ -1346,28 +1380,39 @@ static void clear_dte_entry(u16 devid)
static int __attach_device(struct device *dev,
struct protection_domain *domain)
{
- u16 devid = get_device_id(dev);
- u16 alias = amd_iommu_alias_table[devid];
+ struct iommu_dev_data *dev_data, *alias_data;
+ u16 devid, alias;
+
+ devid = get_device_id(dev);
+ alias = amd_iommu_alias_table[devid];
+ dev_data = get_dev_data(dev);
+ alias_data = get_dev_data(dev_data->alias);
+ if (!alias_data)
+ return -EINVAL;

/* lock domain */
spin_lock(&domain->lock);

/* Some sanity checks */
- if (amd_iommu_pd_table[alias] != NULL &&
- amd_iommu_pd_table[alias] != domain)
+ if (alias_data->domain != NULL &&
+ alias_data->domain != domain)
return -EBUSY;

- if (amd_iommu_pd_table[devid] != NULL &&
- amd_iommu_pd_table[devid] != domain)
+ if (dev_data->domain != NULL &&
+ dev_data->domain != domain)
return -EBUSY;

/* Do real assignment */
if (alias != devid &&
- amd_iommu_pd_table[alias] == NULL)
+ alias_data->domain == NULL) {
+ alias_data->domain = domain;
set_dte_entry(alias, domain);
+ }

- if (amd_iommu_pd_table[devid] == NULL)
+ if (dev_data->domain == NULL) {
+ dev_data->domain = domain;
set_dte_entry(devid, domain);
+ }

/* ready */
spin_unlock(&domain->lock);
@@ -1406,10 +1451,12 @@ static void __detach_device(struct device *dev)
{
u16 devid = get_device_id(dev);
struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
+ struct iommu_dev_data *dev_data = get_dev_data(dev);

BUG_ON(!iommu);

clear_dte_entry(devid);
+ dev_data->domain = NULL;

/*
* If we run in passthrough mode the device must be assigned to the
@@ -1439,18 +1486,23 @@ static void detach_device(struct device *dev)
static struct protection_domain *domain_for_device(struct device *dev)
{
struct protection_domain *dom;
+ struct iommu_dev_data *dev_data, *alias_data;
unsigned long flags;
u16 devid, alias;

- devid = get_device_id(dev);
- alias = amd_iommu_alias_table[devid];
+ devid = get_device_id(dev);
+ alias = amd_iommu_alias_table[devid];
+ dev_data = get_dev_data(dev);
+ alias_data = get_dev_data(dev_data->alias);
+ if (!alias_data)
+ return NULL;

read_lock_irqsave(&amd_iommu_devtable_lock, flags);
- dom = amd_iommu_pd_table[devid];
+ dom = dev_data->domain;
if (dom == NULL &&
- amd_iommu_pd_table[alias] != NULL) {
- __attach_device(dev, amd_iommu_pd_table[alias]);
- dom = amd_iommu_pd_table[devid];
+ alias_data->domain != NULL) {
+ __attach_device(dev, alias_data->domain);
+ dom = alias_data->domain;
}

read_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
@@ -1473,14 +1525,12 @@ static int device_change_notifier(struct notifier_block *nb,

devid = get_device_id(dev);
iommu = amd_iommu_rlookup_table[devid];
- domain = domain_for_device(dev);
-
- if (domain && !dma_ops_domain(domain))
- WARN_ONCE(1, "AMD IOMMU WARNING: device %s already bound "
- "to a non-dma-ops domain\n", dev_name(dev));

switch (action) {
case BUS_NOTIFY_UNBOUND_DRIVER:
+
+ domain = domain_for_device(dev);
+
if (!domain)
goto out;
if (iommu_pass_through)
@@ -1488,6 +1538,11 @@ static int device_change_notifier(struct notifier_block *nb,
detach_device(dev);
break;
case BUS_NOTIFY_ADD_DEVICE:
+
+ iommu_init_device(dev);
+
+ domain = domain_for_device(dev);
+
/* allocate a protection domain if a device is added */
dma_domain = find_protection_domain(devid);
if (dma_domain)
@@ -1502,6 +1557,10 @@ static int device_change_notifier(struct notifier_block *nb,
spin_unlock_irqrestore(&iommu_pd_list_lock, flags);

break;
+ case BUS_NOTIFY_DEL_DEVICE:
+
+ iommu_uninit_device(dev);
+
default:
goto out;
}
@@ -2079,6 +2138,8 @@ static void prealloc_protection_domains(void)
if (!check_device(&dev->dev))
continue;

+ iommu_init_device(&dev->dev);
+
/* Is there already any domain for it? */
if (domain_for_device(&dev->dev))
continue;
@@ -2270,6 +2331,7 @@ static void amd_iommu_domain_destroy(struct iommu_domain *dom)
static void amd_iommu_detach_device(struct iommu_domain *dom,
struct device *dev)
{
+ struct iommu_dev_data *dev_data = dev->archdata.iommu;
struct amd_iommu *iommu;
u16 devid;

@@ -2278,7 +2340,7 @@ static void amd_iommu_detach_device(struct iommu_domain *dom,

devid = get_device_id(dev);

- if (amd_iommu_pd_table[devid] != NULL)
+ if (dev_data->domain != NULL)
detach_device(dev);

iommu = amd_iommu_rlookup_table[devid];
@@ -2293,7 +2355,7 @@ static int amd_iommu_attach_device(struct iommu_domain *dom,
struct device *dev)
{
struct protection_domain *domain = dom->priv;
- struct protection_domain *old_domain;
+ struct iommu_dev_data *dev_data;
struct amd_iommu *iommu;
int ret;
u16 devid;
@@ -2301,14 +2363,15 @@ static int amd_iommu_attach_device(struct iommu_domain *dom,
if (!check_device(dev))
return -EINVAL;

+ dev_data = dev->archdata.iommu;
+
devid = get_device_id(dev);

iommu = amd_iommu_rlookup_table[devid];
if (!iommu)
return -EINVAL;

- old_domain = amd_iommu_pd_table[devid];
- if (old_domain)
+ if (dev_data->domain)
detach_device(dev);

ret = attach_device(dev, domain);
--
1.6.5.3


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