Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux

Pull drm updates from Dave Airlie:
 "This is the main drm pull, it has a shared branch with some alsa
  crossover but everything should be acked by relevant people.

  New drivers:
     - ATMEL HLCDC driver
     - designware HDMI core support (used in multiple SoCs).

  core:
     - lots more atomic modesetting work, properties and atomic ioctl
       (hidden under option)
     - bridge rework allows support for Samsung exynos chromebooks to
       work finally.
     - some more panels supported

  i915:
     - atomic plane update support
     - DSI uses shared DSI infrastructure
     - Skylake basic support is all merged now
     - component framework used for i915/snd-hda interactions
     - write-combine cpu memory mappings
     - engine init code refactored
     - full ppgtt enabled where execlists are enabled.
     - cherryview rps/gpu turbo and pipe CRC support.

  radeon:
     - indirect draw support for evergreen/cayman
     - SMC and manual fan control for SI/CI
     - Displayport audio support

  amdkfd:
     - SDMA usermode queue support
     - replace suballocator usage with more suitable one
     - rework for allowing interfacing to more than radeon

  nouveau:
     - major renaming in prep for later splitting work
     - merge arm platform driver into nouveau
     - GK20A reclocking support

  msm:
     - conversion to atomic modesetting
     - YUV support for mdp4/5
     - eDP support
     - hw cursor for mdp5

  tegra:
     - conversion to atomic modesetting
     - better suspend/resume support for child devices

  rcar-du:
     - interlaced support

  imx:
     - move to using dw_hdmi shared support
     - mode_fixup support

  sti:
     - DVO support
     - HDMI infoframe support

  exynos:
     - refactoring and cleanup, removed lots of internal unnecessary
       abstraction
     - exynos7 DECON display controller support

  Along with the usual bunch of fixes, cleanups etc"

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (724 commits)
  drm/radeon: fix voltage setup on hawaii
  drm/radeon/dp: Set EDP_CONFIGURATION_SET for bridge chips if necessary
  drm/radeon: only enable kv/kb dpm interrupts once v3
  drm/radeon: workaround for CP HW bug on CIK
  drm/radeon: Don't try to enable write-combining without PAT
  drm/radeon: use 0-255 rather than 0-100 for pwm fan range
  drm/i915: Clamp efficient frequency to valid range
  drm/i915: Really ignore long HPD pulses on eDP
  drm/exynos: Add DECON driver
  drm/i915: Correct the base value while updating LP_OUTPUT_HOLD in MIPI_PORT_CTRL
  drm/i915: Insert a command barrier on BLT/BSD cache flushes
  drm/i915: Drop vblank wait from intel_dp_link_down
  drm/exynos: fix NULL pointer reference
  drm/exynos: remove exynos_plane_dpms
  drm/exynos: remove mode property of exynos crtc
  drm/exynos: Remove exynos_plane_dpms() call with no effect
  drm/i915: Squelch overzealous uncore reset WARN_ON
  drm/i915: Take runtime pm reference on hangcheck_info
  drm/i915: Correct the IOSF Dev_FN field for IOSF transfers
  drm/exynos: fix DMA_ATTR_NO_KERNEL_MAPPING usage
  ...

1 files changed, 42 insertions, 47 deletions

diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
index 0b9514b6cd64..076dd606b580 100644
--- a/drivers/gpu/drm/drm_fops.c
+++ b/drivers/gpu/drm/drm_fops.c
@@ -478,64 +478,59 @@ int drm_release(struct inode *inode, struct file *filp)
 }
 EXPORT_SYMBOL(drm_release);
 
-static bool
-drm_dequeue_event(struct drm_file *file_priv,
-		  size_t total, size_t max, struct drm_pending_event **out)
+ssize_t drm_read(struct file *filp, char __user *buffer,
+		 size_t count, loff_t *offset)
 {
+	struct drm_file *file_priv = filp->private_data;
 	struct drm_device *dev = file_priv->minor->dev;
-	struct drm_pending_event *e;
-	unsigned long flags;
-	bool ret = false;
-
-	spin_lock_irqsave(&dev->event_lock, flags);
+	ssize_t ret = 0;
 
-	*out = NULL;
-	if (list_empty(&file_priv->event_list))
-		goto out;
-	e = list_first_entry(&file_priv->event_list,
-			     struct drm_pending_event, link);
-	if (e->event->length + total > max)
-		goto out;
+	if (!access_ok(VERIFY_WRITE, buffer, count))
+		return -EFAULT;
 
-	file_priv->event_space += e->event->length;
-	list_del(&e->link);
-	*out = e;
-	ret = true;
+	spin_lock_irq(&dev->event_lock);
+	for (;;) {
+		if (list_empty(&file_priv->event_list)) {
+			if (ret)
+				break;
 
-out:
-	spin_unlock_irqrestore(&dev->event_lock, flags);
-	return ret;
-}
-
-ssize_t drm_read(struct file *filp, char __user *buffer,
-		 size_t count, loff_t *offset)
-{
-	struct drm_file *file_priv = filp->private_data;
-	struct drm_pending_event *e;
-	size_t total;
-	ssize_t ret;
+			if (filp->f_flags & O_NONBLOCK) {
+				ret = -EAGAIN;
+				break;
+			}
 
-	if ((filp->f_flags & O_NONBLOCK) == 0) {
-		ret = wait_event_interruptible(file_priv->event_wait,
-					       !list_empty(&file_priv->event_list));
-		if (ret < 0)
-			return ret;
-	}
+			spin_unlock_irq(&dev->event_lock);
+			ret = wait_event_interruptible(file_priv->event_wait,
+						       !list_empty(&file_priv->event_list));
+			spin_lock_irq(&dev->event_lock);
+			if (ret < 0)
+				break;
+
+			ret = 0;
+		} else {
+			struct drm_pending_event *e;
+
+			e = list_first_entry(&file_priv->event_list,
+					     struct drm_pending_event, link);
+			if (e->event->length + ret > count)
+				break;
+
+			if (__copy_to_user_inatomic(buffer + ret,
+						    e->event, e->event->length)) {
+				if (ret == 0)
+					ret = -EFAULT;
+				break;
+			}
 
-	total = 0;
-	while (drm_dequeue_event(file_priv, total, count, &e)) {
-		if (copy_to_user(buffer + total,
-				 e->event, e->event->length)) {
-			total = -EFAULT;
+			file_priv->event_space += e->event->length;
+			ret += e->event->length;
+			list_del(&e->link);
 			e->destroy(e);
-			break;
 		}
-
-		total += e->event->length;
-		e->destroy(e);
 	}
+	spin_unlock_irq(&dev->event_lock);
 
-	return total ?: -EAGAIN;
+	return ret;
 }
 EXPORT_SYMBOL(drm_read);