ps3flash: switch to generic_file_llseek_size()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

drivers/char/ps3flash.c

@@ -98,32 +98,8 @@ static int ps3flash_fetch(struct ps3_storage_device *dev, u64 start_sector)
 static loff_t ps3flash_llseek(struct file *file, loff_t offset, int origin)
 {
 	struct ps3_storage_device *dev = ps3flash_dev;
-	loff_t res;
-
-	mutex_lock(&file->f_mapping->host->i_mutex);
-	switch (origin) {
-	case 0:
-		break;
-	case 1:
-		offset += file->f_pos;
-		break;
-	case 2:
-		offset += dev->regions[dev->region_idx].size*dev->blk_size;
-		break;
-	default:
-		offset = -1;
-	}
-	if (offset < 0) {
-		res = -EINVAL;
-		goto out;
-	}
-
-	file->f_pos = offset;
-	res = file->f_pos;
-
-out:
-	mutex_unlock(&file->f_mapping->host->i_mutex);
-	return res;
+	return generic_file_llseek_size(file, offset, origin, MAX_LFS_FILESIZE,
+			dev->regions[dev->region_idx].size*dev->blk_size);
 }
 
 static ssize_t ps3flash_read(char __user *userbuf, void *kernelbuf,