PM / sleep: move SNAPSHOT_SET_SWAP_AREA handling into a helper

Move the handling of the SNAPSHOT_SET_SWAP_AREA ioctl from the main
ioctl helper into a helper function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/kernel/power/user.c b/kernel/power/user.c
index ef90eb1fb86e959df3f56f388ac38ee5f1d7fd04..0cb555f526e4096724bfbee92784c508b9dc5546 100644 (file)
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -196,6 +196,34 @@ unlock:
        return res;
 }
 
+static int snapshot_set_swap_area(struct snapshot_data *data,
+               void __user *argp)
+{
+       struct resume_swap_area swap_area;
+       sector_t offset;
+       dev_t swdev;
+
+       if (swsusp_swap_in_use())
+               return -EPERM;
+       if (copy_from_user(&swap_area, argp, sizeof(swap_area)))
+               return -EFAULT;
+
+       /*
+        * User space encodes device types as two-byte values,
+        * so we need to recode them
+        */
+       swdev = new_decode_dev(swap_area.dev);
+       if (!swdev) {
+               data->swap = -1;
+               return -EINVAL;
+       }
+       offset = swap_area.offset;
+       data->swap = swap_type_of(swdev, offset, NULL);
+       if (data->swap < 0)
+               return -ENODEV;
+       return 0;
+}
+
 static long snapshot_ioctl(struct file *filp, unsigned int cmd,
                                                        unsigned long arg)
 {
@@ -351,34 +379,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
                break;
 
        case SNAPSHOT_SET_SWAP_AREA:
-               if (swsusp_swap_in_use()) {
-                       error = -EPERM;
-               } else {
-                       struct resume_swap_area swap_area;
-                       dev_t swdev;
-
-                       error = copy_from_user(&swap_area, (void __user *)arg,
-                                       sizeof(struct resume_swap_area));
-                       if (error) {
-                               error = -EFAULT;
-                               break;
-                       }
-
-                       /*
-                        * User space encodes device types as two-byte values,
-                        * so we need to recode them
-                        */
-                       swdev = new_decode_dev(swap_area.dev);
-                       if (swdev) {
-                               offset = swap_area.offset;
-                               data->swap = swap_type_of(swdev, offset, NULL);
-                               if (data->swap < 0)
-                                       error = -ENODEV;
-                       } else {
-                               data->swap = -1;
-                               error = -EINVAL;
-                       }
-               }
+               error = snapshot_set_swap_area(data, (void __user *)arg);
                break;
 
        default: