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>

1 files changed, 32 insertions, 1 deletions

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 2d914a49b19a..f64799878d45 100644
--- 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;