AMD IOMMU: add device notifier callback

Impact: inform IOMMU about state change of a device in the driver core

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 15456a3..140875b 100644 (file)
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -47,6 +47,8 @@ struct iommu_cmd {
 
 static int dma_ops_unity_map(struct dma_ops_domain *dma_dom,
                             struct unity_map_entry *e);
+static struct dma_ops_domain *find_protection_domain(u16 devid);
+
 
 /* returns !0 if the IOMMU is caching non-present entries in its TLB */
 static int iommu_has_npcache(struct amd_iommu *iommu)
@@ -844,7 +846,6 @@ static void attach_device(struct amd_iommu *iommu,
        iommu_queue_inv_dev_entry(iommu, devid);
 }
 
-#ifdef CONFIG_IOMMU_API
 /*
  * Removes a device from a protection domain (unlocked)
  */
@@ -881,7 +882,62 @@ static void detach_device(struct protection_domain *domain, u16 devid)
        __detach_device(domain, devid);
        write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
 }
-#endif
+
+static int device_change_notifier(struct notifier_block *nb,
+                                 unsigned long action, void *data)
+{
+       struct device *dev = data;
+       struct pci_dev *pdev = to_pci_dev(dev);
+       u16 devid = calc_devid(pdev->bus->number, pdev->devfn);
+       struct protection_domain *domain;
+       struct dma_ops_domain *dma_domain;
+       struct amd_iommu *iommu;
+
+       if (devid > amd_iommu_last_bdf)
+               goto out;
+
+       devid = amd_iommu_alias_table[devid];
+
+       iommu = amd_iommu_rlookup_table[devid];
+       if (iommu == NULL)
+               goto out;
+
+       domain = domain_for_device(devid);
+
+       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_BOUND_DRIVER:
+               if (domain)
+                       goto out;
+               dma_domain = find_protection_domain(devid);
+               if (!dma_domain)
+                       dma_domain = iommu->default_dom;
+               attach_device(iommu, &dma_domain->domain, devid);
+               printk(KERN_INFO "AMD IOMMU: Using protection domain %d for "
+                      "device %s\n", dma_domain->domain.id, dev_name(dev));
+               break;
+       case BUS_NOTIFY_UNBIND_DRIVER:
+               if (!domain)
+                       goto out;
+               detach_device(domain, devid);
+               break;
+       default:
+               goto out;
+       }
+
+       iommu_queue_inv_dev_entry(iommu, devid);
+       iommu_completion_wait(iommu);
+
+out:
+       return 0;
+}
+
+struct notifier_block device_nb = {
+       .notifier_call = device_change_notifier,
+};
 
 /*****************************************************************************
  *
@@ -1510,6 +1566,8 @@ int __init amd_iommu_init_dma_ops(void)
        /* Make the driver finally visible to the drivers */
        dma_ops = &amd_iommu_dma_ops;
 
+       bus_register_notifier(&pci_bus_type, &device_nb);
+
        return 0;
 
 free_domains: