path: root/include
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authorDaniel Vetter <daniel.vetter@ffwll.ch>2016-06-21 10:54:12 +0200
committerDaniel Vetter <daniel.vetter@ffwll.ch>2016-06-21 21:43:24 +0200
commit95c081c17f284de50eaca60d4d55643a64d39019 (patch)
treec67aa3d3c9008fc1b91d26b58fc9d57f1f820aab /include
parent84601dbdea36634a300c24f93b149a251fc64fed (diff)
drm: Move master pointer from drm_minor to drm_device
There can only be one current master, and it's for the overall device. Render/control minors don't support master-based auth at all. This simplifies the master logic a lot, at least in my eyes: All these additional pointer chases are just confusing. While doing the conversion I spotted some locking fail: - drm_lock/drm_auth check dev->master without holding the master_mutex. This is fallout from commit c996fd0b956450563454e7ccc97a82ca31f9d043 Author: Thomas Hellstrom <thellstrom@vmware.com> Date: Tue Feb 25 19:57:44 2014 +0100 drm: Protect the master management with a drm_device::master_mutex v3 but I honestly don't care one bit about those old legacy drivers using this. - debugfs name info should just grab master_mutex. - And the fbdev helper looked at it to figure out whether someone is using KMS. We just need a consistent value, so READ_ONCE. Aside: We should probably check if anyone has opened a control node too, but I guess current userspace doesn't really do that yet. v2: Balance locking, reported by Julia. v3: Rebase on top of Chris' oops fixes. Cc: Julia Lawall <julia.lawall@lip6.fr> Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v2) Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> (v2) Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1466499262-18717-1-git-send-email-daniel.vetter@ffwll.ch
Diffstat (limited to 'include')
1 files changed, 5 insertions, 4 deletions
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 084fd141e8bf..3d9a7824f111 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -336,7 +336,7 @@ struct drm_file {
void *driver_priv;
struct drm_master *master; /* master this node is currently associated with
- N.B. not always minor->master */
+ N.B. not always dev->master */
* fbs - List of framebuffers associated with this file.
@@ -708,9 +708,6 @@ struct drm_minor {
struct list_head debugfs_list;
struct mutex debugfs_lock; /* Protects debugfs_list. */
- /* currently active master for this node. Protected by master_mutex */
- struct drm_master *master;
@@ -759,6 +756,10 @@ struct drm_device {
struct drm_minor *control; /**< Control node */
struct drm_minor *primary; /**< Primary node */
struct drm_minor *render; /**< Render node */
+ /* currently active master for this device. Protected by master_mutex */
+ struct drm_master *master;
atomic_t unplugged; /**< Flag whether dev is dead */
struct inode *anon_inode; /**< inode for private address-space */
char *unique; /**< unique name of the device */