Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / drivers / iio / industrialio-buffer.c

diff --git a/kernel/drivers/iio/industrialio-buffer.c b/kernel/drivers/iio/industrialio-buffer.c
index 0f6f63b..32bb036 100644 (file)
--- a/kernel/drivers/iio/industrialio-buffer.c
+++ b/kernel/drivers/iio/industrialio-buffer.c
@@ -107,9 +107,10 @@ ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf,
 {
        struct iio_dev *indio_dev = filp->private_data;
        struct iio_buffer *rb = indio_dev->buffer;
+       DEFINE_WAIT_FUNC(wait, woken_wake_function);
        size_t datum_size;
        size_t to_wait;
-       int ret;
+       int ret = 0;
 
        if (!indio_dev->info)
                return -ENODEV;
@@ -131,19 +132,29 @@ ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf,
        else
                to_wait = min_t(size_t, n / datum_size, rb->watermark);
 
+       add_wait_queue(&rb->pollq, &wait);
        do {
-               ret = wait_event_interruptible(rb->pollq,
-                     iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size));
-               if (ret)
-                       return ret;
+               if (!indio_dev->info) {
+                       ret = -ENODEV;
+                       break;
+               }
 
-               if (!indio_dev->info)
-                       return -ENODEV;
+               if (!iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size)) {
+                       if (signal_pending(current)) {
+                               ret = -ERESTARTSYS;
+                               break;
+                       }
+
+                       wait_woken(&wait, TASK_INTERRUPTIBLE,
+                                  MAX_SCHEDULE_TIMEOUT);
+                       continue;
+               }
 
                ret = rb->access->read_first_n(rb, n, buf);
                if (ret == 0 && (filp->f_flags & O_NONBLOCK))
                        ret = -EAGAIN;
-        } while (ret == 0);
+       } while (ret == 0);
+       remove_wait_queue(&rb->pollq, &wait);
 
        return ret;
 }