drm/i915: hold dev->struct_mutex and DRM lock during vblank ring operations

To synchronize clip lists with the X server, the DRM lock must be held while
looking at drawable clip lists. To synchronize with other ring access, the
ring mutex must be held while inserting commands into the ring.  Failure to
do the first resulted in easy visual corruption when moving windows, and the
second could have corrupted the ring with DRI2.

Grabbing the DRM lock involves using the DRM tasklet mechanism, grabbing the
ring mutex means potentially sleeping. Deal with both of these by always
running the tasklet from a work handler.

Also, protect from clip list changes since the vblank request was queued by
making sure the window has at least one rectangle while looking inside,
preventing oopses .

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index eae4ed3956e0..f20ffe17df71 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -90,7 +90,7 @@ struct mem_block {
 typedef struct _drm_i915_vbl_swap {
         struct list_head head;
         drm_drawable_t drw_id;
-        unsigned int plane;
+        unsigned int pipe;
         unsigned int sequence;
 } drm_i915_vbl_swap_t;
 
@@ -240,6 +240,9 @@ typedef struct drm_i915_private {
         u8 saveDACDATA[256*3]; /* 256 3-byte colors */
         u8 saveCR[37];
 
+        /** Work task for vblank-related ring access */
+        struct work_struct vblank_work;
+
         struct {
                 struct drm_mm gtt_space;
 
@@ -285,9 +288,6 @@ typedef struct drm_i915_private {
                  */
                 struct delayed_work retire_work;
 
-                /** Work task for vblank-related ring access */
-                struct work_struct vblank_work;
-
                 uint32_t next_gem_seqno;
 
                 /**
@@ -441,7 +441,7 @@ extern int i915_irq_wait(struct drm_device *dev, void *data,
 void i915_user_irq_get(struct drm_device *dev);
 void i915_user_irq_put(struct drm_device *dev);
 
-extern void i915_gem_vblank_work_handler(struct work_struct *work);
+extern void i915_vblank_work_handler(struct work_struct *work);
 extern irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS);
 extern void i915_driver_irq_preinstall(struct drm_device * dev);
 extern int i915_driver_irq_postinstall(struct drm_device *dev);