staging: android: binder.c: binder_ioctl() cleanup

binder_ioctl() is quite huge and checkpatch dirty - mostly because of
the amount of code for the BINDER_WRITE_READ and BINDER_SET_CONTEXT_MGR.
Moved that code into the new binder_ioctl_write_read() and
binder_ioctl_set_ctx_mgr()
Signed-off-by: Tair Rzayev <tair.rzayev@gmail.com>
Cc: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/binder.c

@@ -2593,41 +2593,23 @@ static unsigned int binder_poll(struct file *filp,
 	return 0;
 }
 
-static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+static int binder_ioctl_write_read(struct file *filp,
+				unsigned int cmd, unsigned long arg,
+				struct binder_thread *thread)
 {
-	int ret;
+	int ret = 0;
 	struct binder_proc *proc = filp->private_data;
-	struct binder_thread *thread;
 	unsigned int size = _IOC_SIZE(cmd);
 	void __user *ubuf = (void __user *)arg;
-	kuid_t curr_euid = current_euid();
-
-	/*pr_info("binder_ioctl: %d:%d %x %lx\n", proc->pid, current->pid, cmd, arg);*/
-
-	trace_binder_ioctl(cmd, arg);
-
-	ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
-	if (ret)
-		goto err_unlocked;
-
-	binder_lock(__func__);
-	thread = binder_get_thread(proc);
-	if (thread == NULL) {
-		ret = -ENOMEM;
-		goto err;
-	}
-
-	switch (cmd) {
-	case BINDER_WRITE_READ: {
 	struct binder_write_read bwr;
 
 	if (size != sizeof(struct binder_write_read)) {
 		ret = -EINVAL;
-			goto err;
+		goto out;
 	}
 	if (copy_from_user(&bwr, ubuf, sizeof(bwr))) {
 		ret = -EFAULT;
-			goto err;
+		goto out;
 	}
 	binder_debug(BINDER_DEBUG_READ_WRITE,
 		     "%d:%d write %lld at %016llx, read %lld at %016llx\n",
@@ -2645,7 +2627,7 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 			bwr.read_consumed = 0;
 			if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
 				ret = -EFAULT;
-				goto err;
+			goto out;
 		}
 	}
 	if (bwr.read_size > 0) {
@@ -2659,7 +2641,7 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		if (ret < 0) {
 			if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
 				ret = -EFAULT;
-				goto err;
+			goto out;
 		}
 	}
 	binder_debug(BINDER_DEBUG_READ_WRITE,
@@ -2669,29 +2651,31 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		     (u64)bwr.read_consumed, (u64)bwr.read_size);
 	if (copy_to_user(ubuf, &bwr, sizeof(bwr))) {
 		ret = -EFAULT;
-			goto err;
+		goto out;
 	}
-		break;
-	}
-	case BINDER_SET_MAX_THREADS:
-		if (copy_from_user(&proc->max_threads, ubuf, sizeof(proc->max_threads))) {
-			ret = -EINVAL;
-			goto err;
-		}
-		break;
-	case BINDER_SET_CONTEXT_MGR:
+out:
+	return ret;
+}
+
+static int binder_ioctl_set_ctx_mgr(struct file *filp)
+{
+	int ret = 0;
+	struct binder_proc *proc = filp->private_data;
+	kuid_t curr_euid = current_euid();
+
 	if (binder_context_mgr_node != NULL) {
 		pr_err("BINDER_SET_CONTEXT_MGR already set\n");
 		ret = -EBUSY;
-			goto err;
+		goto out;
 	}
 	if (uid_valid(binder_context_mgr_uid)) {
 		if (!uid_eq(binder_context_mgr_uid, curr_euid)) {
 			pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n",
 			       from_kuid(&init_user_ns, curr_euid),
-				       from_kuid(&init_user_ns, binder_context_mgr_uid));
+			       from_kuid(&init_user_ns,
+					binder_context_mgr_uid));
 			ret = -EPERM;
-				goto err;
+			goto out;
 		}
 	} else {
 		binder_context_mgr_uid = curr_euid;
@@ -2699,12 +2683,56 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	binder_context_mgr_node = binder_new_node(proc, 0, 0);
 	if (binder_context_mgr_node == NULL) {
 		ret = -ENOMEM;
-			goto err;
+		goto out;
 	}
 	binder_context_mgr_node->local_weak_refs++;
 	binder_context_mgr_node->local_strong_refs++;
 	binder_context_mgr_node->has_strong_ref = 1;
 	binder_context_mgr_node->has_weak_ref = 1;
+out:
+	return ret;
+}
+
+static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	int ret;
+	struct binder_proc *proc = filp->private_data;
+	struct binder_thread *thread;
+	unsigned int size = _IOC_SIZE(cmd);
+	void __user *ubuf = (void __user *)arg;
+
+	/*pr_info("binder_ioctl: %d:%d %x %lx\n",
+			proc->pid, current->pid, cmd, arg);*/
+
+	trace_binder_ioctl(cmd, arg);
+
+	ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
+	if (ret)
+		goto err_unlocked;
+
+	binder_lock(__func__);
+	thread = binder_get_thread(proc);
+	if (thread == NULL) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	switch (cmd) {
+	case BINDER_WRITE_READ:
+		ret = binder_ioctl_write_read(filp, cmd, arg, thread);
+		if (ret)
+			goto err;
+		break;
+	case BINDER_SET_MAX_THREADS:
+		if (copy_from_user(&proc->max_threads, ubuf, sizeof(proc->max_threads))) {
+			ret = -EINVAL;
+			goto err;
+		}
+		break;
+	case BINDER_SET_CONTEXT_MGR:
+		ret = binder_ioctl_set_ctx_mgr(filp);
+		if (ret)
+			goto err;
 		break;
 	case BINDER_THREAD_EXIT:
 		binder_debug(BINDER_DEBUG_THREADS, "%d:%d exit\n",