IOMMU API iommu_detach_devcie() is called to hot remove a PCIe device.
A hot added device will be added into an IOMMU domain when it first does IOMMU
op. So there is no need to add more code for hot add.
Signed-off-by: Fenghua Yu <[email protected]>
---
drivers/pci/pci-driver.c | 8 ++++++++
1 files changed, 8 insertions(+)
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index e5d47be..b8f0592 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -17,6 +17,7 @@
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/cpu.h>
+#include <linux/iommu.h>
#include "pci.h"
struct pci_dynid {
@@ -390,6 +391,13 @@ static int pci_device_remove(struct device * dev)
*/
pci_dev_put(pci_dev);
+
+ /*
+ * Remove this pci device from its iommu domain.
+ */
+ if (iommu_found())
+ iommu_detach_device(NULL, dev);
+
return 0;
}
On Fri, Oct 02, 2009 at 02:18:44PM -0700, Fenghua Yu wrote:
> IOMMU API iommu_detach_devcie() is called to hot remove a PCIe device.
>
> A hot added device will be added into an IOMMU domain when it first does IOMMU
> op. So there is no need to add more code for hot add.
>
> Signed-off-by: Fenghua Yu <[email protected]>
>
> ---
>
> drivers/pci/pci-driver.c | 8 ++++++++
> 1 files changed, 8 insertions(+)
>
> diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
> index e5d47be..b8f0592 100644
> --- a/drivers/pci/pci-driver.c
> +++ b/drivers/pci/pci-driver.c
> @@ -17,6 +17,7 @@
> #include <linux/slab.h>
> #include <linux/sched.h>
> #include <linux/cpu.h>
> +#include <linux/iommu.h>
> #include "pci.h"
>
> struct pci_dynid {
> @@ -390,6 +391,13 @@ static int pci_device_remove(struct device * dev)
> */
>
> pci_dev_put(pci_dev);
> +
> + /*
> + * Remove this pci device from its iommu domain.
> + */
> + if (iommu_found())
> + iommu_detach_device(NULL, dev);
> +
> return 0;
> }
NACK!
This breaks with AMD IOMMU driver.
Just implement a VT-d specific notifier callback for device removal on
the pci bus.
Joerg
> NACK!
>
> This breaks with AMD IOMMU driver.
> Just implement a VT-d specific notifier callback for device removal on
> the pci bus.
You are right. Will change to AMD's method.
Thanks.
-Fenghua
To support PCIe hot plug in IOMMU, we register a notifier to respond to device
change action.
When the notifier gets BUS_NOTIFY_UNBOUND_DRIVER, it removes the device from its
DMAR domain.
A hot added device will be added into an IOMMU domain when it first does IOMMU
op. So there is no need to add more code for hot add.
Signed-off-by: Fenghua Yu <[email protected]>
---
intel-iommu.c | 29 +++++++++++++++++++++++++++++
1 files changed, 29 insertions(+)
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 855dd7c..d8b8cfc 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -3193,6 +3193,33 @@ static int __init init_iommu_sysfs(void)
}
#endif /* CONFIG_PM */
+/*
+ * Here we only respond to action of unbound device from driver.
+ *
+ * Added device is not attached to its DMAR domain here yet. That will happen
+ * when mapping the device to iova.
+ */
+static int device_notifier(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct device *dev = data;
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct dmar_domain *domain;
+
+ domain = find_domain(pdev);
+ if (!domain)
+ return 0;
+
+ if (action == BUS_NOTIFY_UNBOUND_DRIVER && !iommu_pass_through)
+ domain_remove_one_dev_info(domain, pdev);
+
+ return 0;
+}
+
+static struct notifier_block device_nb = {
+ .notifier_call = device_notifier,
+};
+
int __init intel_iommu_init(void)
{
int ret = 0;
@@ -3245,6 +3272,8 @@ int __init intel_iommu_init(void)
register_iommu(&intel_iommu_ops);
+ bus_register_notifier(&pci_bus_type, &device_nb);
+
return 0;
}
On Tue, Oct 6, 2009 at 11:23 AM, Fenghua Yu <[email protected]> wrote:
> To support PCIe hot plug in IOMMU, we register a notifier to respond to device
> change action.
>
> When the notifier gets BUS_NOTIFY_UNBOUND_DRIVER, it removes the device from its
> DMAR domain.
>
> A hot added device will be added into an IOMMU domain when it first does IOMMU
> op. So there is no need to add more code for hot add.
>
> Signed-off-by: Fenghua Yu <[email protected]>
>
> ---
>
> ?intel-iommu.c | ? 29 +++++++++++++++++++++++++++++
> ?1 files changed, 29 insertions(+)
>
> diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
> index 855dd7c..d8b8cfc 100644
> --- a/drivers/pci/intel-iommu.c
> +++ b/drivers/pci/intel-iommu.c
> @@ -3193,6 +3193,33 @@ static int __init init_iommu_sysfs(void)
> ?}
> ?#endif /* CONFIG_PM */
>
> +/*
> + * Here we only respond to action of unbound device from driver.
> + *
> + * Added device is not attached to its DMAR domain here yet. That will happen
> + * when mapping the device to iova.
> + */
> +static int device_notifier(struct notifier_block *nb,
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned long action, void *data)
> +{
> + ? ? ? struct device *dev = data;
> + ? ? ? struct pci_dev *pdev = to_pci_dev(dev);
> + ? ? ? struct dmar_domain *domain;
> +
> + ? ? ? domain = find_domain(pdev);
> + ? ? ? if (!domain)
> + ? ? ? ? ? ? ? return 0;
> +
> + ? ? ? if (action == BUS_NOTIFY_UNBOUND_DRIVER && !iommu_pass_through)
> + ? ? ? ? ? ? ? domain_remove_one_dev_info(domain, pdev);
> +
> + ? ? ? return 0;
> +}
> +
> +static struct notifier_block device_nb = {
> + ? ? ? .notifier_call = device_notifier,
> +};
> +
> ?int __init intel_iommu_init(void)
> ?{
> ? ? ? ?int ret = 0;
> @@ -3245,6 +3272,8 @@ int __init intel_iommu_init(void)
>
> ? ? ? ?register_iommu(&intel_iommu_ops);
>
> + ? ? ? bus_register_notifier(&pci_bus_type, &device_nb);
> +
> ? ? ? ?return 0;
> ?}
>
it seems this one should be get into 2.6.32....and .stable
otherwise second hot plug in the same pcie slot will not work with dma.
YH