Commit 75ae95a7 authored by David Herrmann's avatar David Herrmann Committed by Daniel Vetter
Browse files

drm: remove redundant drm_file->uid 



Each DRM file-context caches the EUID of the process that opened the file.
It is used exclusively for debugging purposes in /proc/dri/ and friends.

Note, however, that we can already fetch the EUID from
priv->pid->task->creds. The pointer-chasing will not hurt us, since it is
only about debugging, anyway.

Since we already are in an rcu-read-side, we can use __task_cred() rather
than task_cred_xxx().

Signed-off-by: default avatarDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160901124837.680-2-dh.herrmann@gmail.com
parent 9f8cf165

drivers/gpu/drm/drm_fops.c

+0 −1
Original line number Diff line number Diff line
@@ -199,7 +199,6 @@ static int drm_open_helper(struct file *filp, struct drm_minor *minor) 


	filp->private_data = priv;

	priv->filp = filp;

	priv->uid = current_euid();

	priv->pid = get_pid(task_pid(current));

	priv->minor = minor;

drivers/gpu/drm/drm_info.c

+3 −1
Original line number Diff line number Diff line
@@ -80,6 +80,7 @@ int drm_clients_info(struct seq_file *m, void *data) 
	struct drm_info_node *node = (struct drm_info_node *) m->private;

	struct drm_device *dev = node->minor->dev;

	struct drm_file *priv;

	kuid_t uid;



	seq_printf(m,

		   "%20s %5s %3s master a %5s %10s\n",
@@ -98,13 +99,14 @@ int drm_clients_info(struct seq_file *m, void *data) 


		rcu_read_lock(); /* locks pid_task()->comm */

		task = pid_task(priv->pid, PIDTYPE_PID);

		uid = task ? __task_cred(task)->euid : GLOBAL_ROOT_UID;

		seq_printf(m, "%20s %5d %3d   %c    %c %5d %10u\n",

			   task ? task->comm : "<unknown>",

			   pid_vnr(priv->pid),

			   priv->minor->index,

			   drm_is_current_master(priv) ? 'y' : 'n',

			   priv->authenticated ? 'y' : 'n',

			   from_kuid_munged(seq_user_ns(m), priv->uid),

			   from_kuid_munged(seq_user_ns(m), uid),

			   priv->magic);

		rcu_read_unlock();

	}

include/drm/drmP.h

+0 −1
Original line number Diff line number Diff line
@@ -379,7 +379,6 @@ struct drm_file { 
	unsigned is_master:1;



	struct pid *pid;

	kuid_t uid;

	drm_magic_t magic;

	struct list_head lhead;

	struct drm_minor *minor;

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