x86/amd-iommu: Search for existind dev_data before allocting a new one

Search for existing dev_data first will allow to switch
dev_data->alias to just store dev_data instead of struct
device.

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 2d914a49b19a8eb774a6359f009832870ded0238..f64799878d45d7e1140bf5ec75058aa75becee67 100644 (file)
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -102,6 +102,37 @@ static void free_dev_data(struct iommu_dev_data *dev_data)
        kfree(dev_data);
 }
 
+static struct iommu_dev_data *search_dev_data(u16 devid)
+{
+       struct iommu_dev_data *dev_data;
+       unsigned long flags;
+
+       spin_lock_irqsave(&dev_data_list_lock, flags);
+       list_for_each_entry(dev_data, &dev_data_list, dev_data_list) {
+               if (dev_data->devid == devid)
+                       goto out_unlock;
+       }
+
+       dev_data = NULL;
+
+out_unlock:
+       spin_unlock_irqrestore(&dev_data_list_lock, flags);
+
+       return dev_data;
+}
+
+static struct iommu_dev_data *find_dev_data(u16 devid)
+{
+       struct iommu_dev_data *dev_data;
+
+       dev_data = search_dev_data(devid);
+
+       if (dev_data == NULL)
+               dev_data = alloc_dev_data(devid);
+
+       return dev_data;
+}
+
 static inline u16 get_device_id(struct device *dev)
 {
        struct pci_dev *pdev = to_pci_dev(dev);
@@ -178,7 +209,7 @@ static int iommu_init_device(struct device *dev)
        if (dev->archdata.iommu)
                return 0;
 
-       dev_data = alloc_dev_data(get_device_id(dev));
+       dev_data = find_dev_data(get_device_id(dev));
        if (!dev_data)
                return -ENOMEM;