From 862302ffe422378a5213f558fc5cdf62c37050a9 Mon Sep 17 00:00:00 2001 From: Thomas Hellstrom Date: Wed, 2 Dec 2009 18:15:25 +0000 Subject: drm: Add support for drm master_[set|drop] callbacks. The vmwgfx driver has a per master rw lock around TTM, to guarantee mutual exclusion when needed. This is typically when all evictable buffers are evicted due to 1) vt switch 2) master switch 3) suspend / resume. In the multi-master case, on master switch the new master takes the previously active master lock in write mode, and then evicts all buffers. Any clients to previous masters will then block on that lock when trying to validate a buffer. fbdev also acts as a virtual master wrt this. Signed-off-by: Thomas Hellstrom Signed-off-by: Jakob Bornecrantz Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_fops.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'drivers/gpu/drm/drm_fops.c') diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index 8ac7fbf6b2b7..08d14df3bb42 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -300,6 +300,18 @@ static int drm_open_helper(struct inode *inode, struct file *filp, goto out_free; } } + mutex_lock(&dev->struct_mutex); + if (dev->driver->master_set) { + ret = dev->driver->master_set(dev, priv, true); + if (ret) { + /* drop both references if this fails */ + drm_master_put(&priv->minor->master); + drm_master_put(&priv->master); + mutex_unlock(&dev->struct_mutex); + goto out_free; + } + } + mutex_unlock(&dev->struct_mutex); } else { /* get a reference to the master */ priv->master = drm_master_get(priv->minor->master); @@ -533,6 +545,8 @@ int drm_release(struct inode *inode, struct file *filp) if (file_priv->minor->master == file_priv->master) { /* drop the reference held my the minor */ + if (dev->driver->master_drop) + dev->driver->master_drop(dev, file_priv, true); drm_master_put(&file_priv->minor->master); } } -- cgit v1.2.3