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authorJoerg Roedel <joerg.roedel@amd.com>2011-12-01 18:49:45 +0400
committerJoerg Roedel <joerg.roedel@amd.com>2011-12-12 17:54:58 +0400
commit5abcdba4fa535c29f736455e37229ee97e0e7f5d (patch)
tree228892cf94773b3215fa588fe8e5fc617afa7591
parent400a28a05f2cc1a311acb4ff6ac64d8402d21678 (diff)
downloadlinux-5abcdba4fa535c29f736455e37229ee97e0e7f5d.tar.xz
iommu/amd: Put IOMMUv2 capable devices in pt_domain
If the device starts to use IOMMUv2 features the dma handles need to stay valid. The only sane way to do this is to use a identity mapping for the device and not translate it by the iommu. This is implemented with this patch. Since this lifts the device-isolation there is also a new kernel parameter which allows to disable that feature. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
-rw-r--r--Documentation/kernel-parameters.txt5
-rw-r--r--drivers/iommu/amd_iommu.c94
-rw-r--r--drivers/iommu/amd_iommu_init.c4
-rw-r--r--drivers/iommu/amd_iommu_types.h4
4 files changed, 91 insertions, 16 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 81c287fad79d..22152ed148a5 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -329,6 +329,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
is a lot of faster
off - do not initialize any AMD IOMMU found in
the system
+ force_isolation - Force device isolation for all
+ devices. The IOMMU driver is not
+ allowed anymore to lift isolation
+ requirements as needed. This option
+ does not override iommu=pt
amijoy.map= [HW,JOY] Amiga joystick support
Map of devices attached to JOY0DAT and JOY1DAT
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 661e2bb4ac15..7ccfc80ceb7a 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -67,6 +67,7 @@ struct iommu_cmd {
};
static void update_domain(struct protection_domain *domain);
+static int __init alloc_passthrough_domain(void);
/****************************************************************************
*
@@ -147,6 +148,24 @@ static struct iommu_dev_data *get_dev_data(struct device *dev)
return dev->archdata.iommu;
}
+static bool pci_iommuv2_capable(struct pci_dev *pdev)
+{
+ static const int caps[] = {
+ PCI_EXT_CAP_ID_ATS,
+ PCI_PRI_CAP,
+ PCI_PASID_CAP,
+ };
+ int i, pos;
+
+ for (i = 0; i < 3; ++i) {
+ pos = pci_find_ext_capability(pdev, caps[i]);
+ if (pos == 0)
+ return false;
+ }
+
+ return true;
+}
+
/*
* In this function the list of preallocated protection domains is traversed to
* find the domain for a specific device
@@ -204,6 +223,7 @@ static bool check_device(struct device *dev)
static int iommu_init_device(struct device *dev)
{
+ struct pci_dev *pdev = to_pci_dev(dev);
struct iommu_dev_data *dev_data;
u16 alias;
@@ -228,6 +248,13 @@ static int iommu_init_device(struct device *dev)
dev_data->alias_data = alias_data;
}
+ if (pci_iommuv2_capable(pdev)) {
+ struct amd_iommu *iommu;
+
+ iommu = amd_iommu_rlookup_table[dev_data->devid];
+ dev_data->iommu_v2 = iommu->is_iommu_v2;
+ }
+
dev->archdata.iommu = dev_data;
return 0;
@@ -1762,7 +1789,7 @@ static void __detach_device(struct iommu_dev_data *dev_data)
* passthrough domain if it is detached from any other domain.
* Make sure we can deassign from the pt_domain itself.
*/
- if (iommu_pass_through &&
+ if (dev_data->passthrough &&
(dev_data->domain == NULL && domain != pt_domain))
__attach_device(dev_data, pt_domain);
}
@@ -1820,18 +1847,20 @@ static struct protection_domain *domain_for_device(struct device *dev)
static int device_change_notifier(struct notifier_block *nb,
unsigned long action, void *data)
{
- struct device *dev = data;
- u16 devid;
- struct protection_domain *domain;
struct dma_ops_domain *dma_domain;
+ struct protection_domain *domain;
+ struct iommu_dev_data *dev_data;
+ struct device *dev = data;
struct amd_iommu *iommu;
unsigned long flags;
+ u16 devid;
if (!check_device(dev))
return 0;
- devid = get_device_id(dev);
- iommu = amd_iommu_rlookup_table[devid];
+ devid = get_device_id(dev);
+ iommu = amd_iommu_rlookup_table[devid];
+ dev_data = get_dev_data(dev);
switch (action) {
case BUS_NOTIFY_UNBOUND_DRIVER:
@@ -1840,7 +1869,7 @@ static int device_change_notifier(struct notifier_block *nb,
if (!domain)
goto out;
- if (iommu_pass_through)
+ if (dev_data->passthrough)
break;
detach_device(dev);
break;
@@ -2436,8 +2465,9 @@ static int amd_iommu_dma_supported(struct device *dev, u64 mask)
*/
static void prealloc_protection_domains(void)
{
- struct pci_dev *dev = NULL;
+ struct iommu_dev_data *dev_data;
struct dma_ops_domain *dma_dom;
+ struct pci_dev *dev = NULL;
u16 devid;
for_each_pci_dev(dev) {
@@ -2446,6 +2476,16 @@ static void prealloc_protection_domains(void)
if (!check_device(&dev->dev))
continue;
+ dev_data = get_dev_data(&dev->dev);
+ if (!amd_iommu_force_isolation && dev_data->iommu_v2) {
+ /* Make sure passthrough domain is allocated */
+ alloc_passthrough_domain();
+ dev_data->passthrough = true;
+ attach_device(&dev->dev, pt_domain);
+ pr_info("AMD-Vi: Using passthough domain for device %s\n",
+ dev_name(&dev->dev));
+ }
+
/* Is there already any domain for it? */
if (domain_for_device(&dev->dev))
continue;
@@ -2476,6 +2516,7 @@ static struct dma_map_ops amd_iommu_dma_ops = {
static unsigned device_dma_ops_init(void)
{
+ struct iommu_dev_data *dev_data;
struct pci_dev *pdev = NULL;
unsigned unhandled = 0;
@@ -2485,7 +2526,12 @@ static unsigned device_dma_ops_init(void)
continue;
}
- pdev->dev.archdata.dma_ops = &amd_iommu_dma_ops;
+ dev_data = get_dev_data(&pdev->dev);
+
+ if (!dev_data->passthrough)
+ pdev->dev.archdata.dma_ops = &amd_iommu_dma_ops;
+ else
+ pdev->dev.archdata.dma_ops = &nommu_dma_ops;
}
return unhandled;
@@ -2612,6 +2658,20 @@ out_err:
return NULL;
}
+static int __init alloc_passthrough_domain(void)
+{
+ if (pt_domain != NULL)
+ return 0;
+
+ /* allocate passthrough domain */
+ pt_domain = protection_domain_alloc();
+ if (!pt_domain)
+ return -ENOMEM;
+
+ pt_domain->mode = PAGE_MODE_NONE;
+
+ return 0;
+}
static int amd_iommu_domain_init(struct iommu_domain *dom)
{
struct protection_domain *domain;
@@ -2798,21 +2858,23 @@ static struct iommu_ops amd_iommu_ops = {
int __init amd_iommu_init_passthrough(void)
{
- struct amd_iommu *iommu;
+ struct iommu_dev_data *dev_data;
struct pci_dev *dev = NULL;
+ struct amd_iommu *iommu;
u16 devid;
+ int ret;
- /* allocate passthrough domain */
- pt_domain = protection_domain_alloc();
- if (!pt_domain)
- return -ENOMEM;
-
- pt_domain->mode |= PAGE_MODE_NONE;
+ ret = alloc_passthrough_domain();
+ if (ret)
+ return ret;
for_each_pci_dev(dev) {
if (!check_device(&dev->dev))
continue;
+ dev_data = get_dev_data(&dev->dev);
+ dev_data->passthrough = true;
+
devid = get_device_id(&dev->dev);
iommu = amd_iommu_rlookup_table[devid];
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index d1e5067852d4..7c3fd572a23b 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -146,6 +146,8 @@ u32 amd_iommu_max_pasids __read_mostly = ~0;
bool amd_iommu_v2_present __read_mostly;
+bool amd_iommu_force_isolation __read_mostly;
+
/*
* The ACPI table parsing functions set this variable on an error
*/
@@ -1642,6 +1644,8 @@ static int __init parse_amd_iommu_options(char *str)
amd_iommu_unmap_flush = true;
if (strncmp(str, "off", 3) == 0)
amd_iommu_disabled = true;
+ if (strncmp(str, "force_isolation", 15) == 0)
+ amd_iommu_force_isolation = true;
}
return 1;
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index 7e81094ab73b..96c652fae0e5 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -330,6 +330,8 @@ struct iommu_dev_data {
struct protection_domain *domain; /* Domain the device is bound to */
atomic_t bind; /* Domain attach reverent count */
u16 devid; /* PCI Device ID */
+ bool iommu_v2; /* Device can make use of IOMMUv2 */
+ bool passthrough; /* Default for device is pt_domain */
struct {
bool enabled;
int qdep;
@@ -575,6 +577,8 @@ extern u32 amd_iommu_max_pasids;
extern bool amd_iommu_v2_present;
+extern bool amd_iommu_force_isolation;
+
/* takes bus and device/function and returns the device id
* FIXME: should that be in generic PCI code? */
static inline u16 calc_devid(u8 bus, u8 devfn)