Well we can't use that directly since that code must hold dev->event_lock already. Extract an _unlocked version.
Embarrassingly I've totally forgotten about this patch and any kind of event-based vblank wait totally blew up, killing the kernel.
v2: Pick the right base struct, someone didn't noticed that gcc was unhappy. No bug since the addresses at least matched (Daniel Stone)
Cc: Alex Deucher alexander.deucher@amd.com Cc: Daniel Stone daniels@collabora.com Cc: Laurent Pinchart laurent.pinchart@ideasonboard.com Reviewed-by: Daniel Stone daniels@collabora.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com --- drivers/gpu/drm/drm_fops.c | 64 +++++++++++++++++++++++++++++++++++----------- drivers/gpu/drm/drm_irq.c | 11 +++----- include/drm/drmP.h | 4 +++ 3 files changed, 57 insertions(+), 22 deletions(-)
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index e13501e3606e..eb6a02f78697 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -678,7 +678,7 @@ unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) EXPORT_SYMBOL(drm_poll);
/** - * drm_event_reserve_init - init a DRM event and reserve space for it + * drm_event_reserve_init_locked - init a DRM event and reserve space for it * @dev: DRM device * @file_priv: DRM file private data * @p: tracking structure for the pending event @@ -694,24 +694,20 @@ EXPORT_SYMBOL(drm_poll); * If callers embedded @p into a larger structure it must be allocated with * kmalloc and @p must be the first member element. * + * This is the locked version of drm_event_reserve_init() for callers which + * already hold dev->event_lock. + * * RETURNS: * * 0 on success or a negative error code on failure. */ -int drm_event_reserve_init(struct drm_device *dev, - struct drm_file *file_priv, - struct drm_pending_event *p, - struct drm_event *e) +int drm_event_reserve_init_locked(struct drm_device *dev, + struct drm_file *file_priv, + struct drm_pending_event *p, + struct drm_event *e) { - unsigned long flags; - int ret = 0; - - spin_lock_irqsave(&dev->event_lock, flags); - - if (file_priv->event_space < e->length) { - ret = -ENOMEM; - goto out; - } + if (file_priv->event_space < e->length) + return -ENOMEM;
file_priv->event_space -= e->length;
@@ -721,8 +717,46 @@ int drm_event_reserve_init(struct drm_device *dev, /* we *could* pass this in as arg, but everyone uses kfree: */ p->destroy = (void (*) (struct drm_pending_event *)) kfree;
-out: + return 0; +} +EXPORT_SYMBOL(drm_event_reserve_init_locked); + +/** + * drm_event_reserve_init - init a DRM event and reserve space for it + * @dev: DRM device + * @file_priv: DRM file private data + * @p: tracking structure for the pending event + * @e: actual event data to deliver to userspace + * + * This function prepares the passed in event for eventual delivery. If the event + * doesn't get delivered (because the IOCTL fails later on, before queuing up + * anything) then the even must be cancelled and freed using + * drm_event_cancel_free(). Successfully initialized events should be sent out + * using drm_send_event() or drm_send_event_locked() to signal completion of the + * asynchronous event to userspace. + * + * If callers embedded @p into a larger structure it must be allocated with + * kmalloc and @p must be the first member element. + * + * Callers which already hold dev->event_lock should use + * drm_event_reserve_init() instead. + * + * RETURNS: + * + * 0 on success or a negative error code on failure. + */ +int drm_event_reserve_init(struct drm_device *dev, + struct drm_file *file_priv, + struct drm_pending_event *p, + struct drm_event *e) +{ + unsigned long flags; + int ret; + + spin_lock_irqsave(&dev->event_lock, flags); + ret = drm_event_reserve_init_locked(dev, file_priv, p, e); spin_unlock_irqrestore(&dev->event_lock, flags); + return ret; } EXPORT_SYMBOL(drm_event_reserve_init); diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 4ec8bca643ac..96d03ac38ef7 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -1598,9 +1598,6 @@ static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe, e->event.base.type = DRM_EVENT_VBLANK; e->event.base.length = sizeof(e->event); e->event.user_data = vblwait->request.signal; - e->base.event = &e->event.base; - e->base.file_priv = file_priv; - e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
spin_lock_irqsave(&dev->event_lock, flags);
@@ -1616,12 +1613,12 @@ static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe, goto err_unlock; }
- if (file_priv->event_space < sizeof(e->event)) { - ret = -EBUSY; + ret = drm_event_reserve_init_locked(dev, file_priv, &e->base, + &e->event.base); + + if (ret) goto err_unlock; - }
- file_priv->event_space -= sizeof(e->event); seq = drm_vblank_count_and_time(dev, pipe, &now);
if ((vblwait->request.type & _DRM_VBLANK_NEXTONMISS) && diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 306ef32ec086..1b71852d0a55 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -926,6 +926,10 @@ ssize_t drm_read(struct file *filp, char __user *buffer, int drm_release(struct inode *inode, struct file *filp); int drm_new_set_master(struct drm_device *dev, struct drm_file *fpriv); unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait); +int drm_event_reserve_init_locked(struct drm_device *dev, + struct drm_file *file_priv, + struct drm_pending_event *p, + struct drm_event *e); int drm_event_reserve_init(struct drm_device *dev, struct drm_file *file_priv, struct drm_pending_event *p,