From: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Wed, 2 Aug 2017 13:56:02 +0200
Subject: drm: Document device unplug infrastructure
Git-commit: c07dcd61a0e57c6840c23d90cb1beddad7d682a1
Patch-mainline: v4.14-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166
While at it, also ocd and give them a consistent drm_dev_ prefix, like
the other device instance functionality. Plus move the functions into
the right places.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170802115604.12734-3-daniel.vetter@ffwll.ch
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/gpu/drm/drm_drv.c | 24 +++++++++++++++++++++---
drivers/gpu/drm/drm_file.c | 2 +-
drivers/gpu/drm/drm_gem.c | 2 +-
drivers/gpu/drm/drm_gem_cma_helper.c | 2 +-
drivers/gpu/drm/drm_ioctl.c | 4 ++--
drivers/gpu/drm/drm_vm.c | 2 +-
drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c | 2 +-
drivers/gpu/drm/udl/udl_connector.c | 2 +-
drivers/gpu/drm/udl/udl_drv.c | 2 +-
drivers/gpu/drm/udl/udl_fb.c | 2 +-
include/drm/drmP.h | 13 -------------
include/drm/drm_drv.h | 22 ++++++++++++++++++++--
12 files changed, 51 insertions(+), 28 deletions(-)
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -291,7 +291,7 @@ struct drm_minor *drm_minor_acquire(unsi
if (!minor) {
return ERR_PTR(-ENODEV);
- } else if (drm_device_is_unplugged(minor->dev)) {
+ } else if (drm_dev_is_unplugged(minor->dev)) {
drm_dev_unref(minor->dev);
return ERR_PTR(-ENODEV);
}
@@ -364,7 +364,22 @@ void drm_put_dev(struct drm_device *dev)
}
EXPORT_SYMBOL(drm_put_dev);
-void drm_unplug_dev(struct drm_device *dev)
+static void drm_device_set_unplugged(struct drm_device *dev)
+{
+ smp_wmb();
+ atomic_set(&dev->unplugged, 1);
+}
+
+/**
+ * drm_dev_unplug - unplug a DRM device
+ * @dev: DRM device
+ *
+ * This unplugs a hotpluggable DRM device, which makes it inaccessible to
+ * userspace operations. Entry-points can use drm_dev_is_unplugged(). This
+ * essentially unregisters the device like drm_dev_unregister(), but can be
+ * called while there are still open users of @dev.
+ */
+void drm_dev_unplug(struct drm_device *dev)
{
/* for a USB device */
if (drm_core_check_feature(dev, DRIVER_MODESET))
@@ -383,7 +398,7 @@ void drm_unplug_dev(struct drm_device *d
}
mutex_unlock(&drm_global_mutex);
}
-EXPORT_SYMBOL(drm_unplug_dev);
+EXPORT_SYMBOL(drm_dev_unplug);
/*
* DRM internal mount
@@ -835,6 +850,9 @@ EXPORT_SYMBOL(drm_dev_register);
* drm_dev_register() but does not deallocate the device. The caller must call
* drm_dev_unref() to drop their final reference.
*
+ * A special form of unregistering for hotpluggable devices is drm_dev_unplug(),
+ * which can be called while there are still open users of @dev.
+ *
* This should be called first in the device teardown code to make sure
* userspace can't access the device instance any more.
*/
--- a/drivers/gpu/drm/drm_file.c
+++ b/drivers/gpu/drm/drm_file.c
@@ -436,7 +436,7 @@ int drm_release(struct inode *inode, str
if (!--dev->open_count) {
drm_lastclose(dev);
- if (drm_device_is_unplugged(dev))
+ if (drm_dev_is_unplugged(dev))
drm_put_dev(dev);
}
mutex_unlock(&drm_global_mutex);
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -1001,7 +1001,7 @@ int drm_gem_mmap(struct file *filp, stru
struct drm_vma_offset_node *node;
int ret;
- if (drm_device_is_unplugged(dev))
+ if (drm_dev_is_unplugged(dev))
return -ENODEV;
drm_vma_offset_lock_lookup(dev->vma_offset_manager);
--- a/drivers/gpu/drm/drm_gem_cma_helper.c
+++ b/drivers/gpu/drm/drm_gem_cma_helper.c
@@ -390,7 +390,7 @@ unsigned long drm_gem_cma_get_unmapped_a
struct drm_device *dev = priv->minor->dev;
struct drm_vma_offset_node *node;
- if (drm_device_is_unplugged(dev))
+ if (drm_dev_is_unplugged(dev))
return -ENODEV;
drm_vma_offset_lock_lookup(dev->vma_offset_manager);
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -716,7 +716,7 @@ long drm_ioctl_kernel(struct file *file,
struct drm_device *dev = file_priv->minor->dev;
int retcode;
- if (drm_device_is_unplugged(dev))
+ if (drm_dev_is_unplugged(dev))
return -ENODEV;
retcode = drm_ioctl_permit(flags, file_priv);
@@ -765,7 +765,7 @@ long drm_ioctl(struct file *filp,
dev = file_priv->minor->dev;
- if (drm_device_is_unplugged(dev))
+ if (drm_dev_is_unplugged(dev))
return -ENODEV;
is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
--- a/drivers/gpu/drm/drm_vm.c
+++ b/drivers/gpu/drm/drm_vm.c
@@ -631,7 +631,7 @@ int drm_legacy_mmap(struct file *filp, s
struct drm_device *dev = priv->minor->dev;
int ret;
- if (drm_device_is_unplugged(dev))
+ if (drm_dev_is_unplugged(dev))
return -ENODEV;
mutex_lock(&dev->struct_mutex);
--- a/drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
+++ b/drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
@@ -56,7 +56,7 @@ static const struct drm_connector_helper
static enum drm_connector_status
tinydrm_connector_detect(struct drm_connector *connector, bool force)
{
- if (drm_device_is_unplugged(connector->dev))
+ if (drm_dev_is_unplugged(connector->dev))
return connector_status_disconnected;
return connector->status;
--- a/drivers/gpu/drm/udl/udl_connector.c
+++ b/drivers/gpu/drm/udl/udl_connector.c
@@ -96,7 +96,7 @@ static int udl_mode_valid(struct drm_con
static enum drm_connector_status
udl_detect(struct drm_connector *connector, bool force)
{
- if (drm_device_is_unplugged(connector->dev))
+ if (drm_dev_is_unplugged(connector->dev))
return connector_status_disconnected;
return connector_status_connected;
}
--- a/drivers/gpu/drm/udl/udl_drv.c
+++ b/drivers/gpu/drm/udl/udl_drv.c
@@ -102,7 +102,7 @@ static void udl_usb_disconnect(struct us
drm_kms_helper_poll_disable(dev);
udl_fbdev_unplug(dev);
udl_drop_usb(dev);
- drm_unplug_dev(dev);
+ drm_dev_unplug(dev);
}
/*
--- a/drivers/gpu/drm/udl/udl_fb.c
+++ b/drivers/gpu/drm/udl/udl_fb.c
@@ -198,7 +198,7 @@ static int udl_fb_open(struct fb_info *i
struct udl_device *udl = dev->dev_private;
/* If the USB device is gone, we don't accept new opens */
- if (drm_device_is_unplugged(udl->ddev))
+ if (drm_dev_is_unplugged(udl->ddev))
return -ENODEV;
ufbdev->fb_count++;
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -320,19 +320,6 @@ static __inline__ int drm_core_check_fea
return ((dev->driver->driver_features & feature) ? 1 : 0);
}
-static inline void drm_device_set_unplugged(struct drm_device *dev)
-{
- smp_wmb();
- atomic_set(&dev->unplugged, 1);
-}
-
-static inline int drm_device_is_unplugged(struct drm_device *dev)
-{
- int ret = atomic_read(&dev->unplugged);
- smp_rmb();
- return ret;
-}
-
/******************************************************************/
/** \name Internal function definitions */
/*@{*/
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -30,7 +30,8 @@
#include <linux/list.h>
#include <linux/irqreturn.h>
-struct drm_device;
+#include <drm/drm_device.h>
+
struct drm_file;
struct drm_gem_object;
struct drm_master;
@@ -613,7 +614,24 @@ void drm_dev_unregister(struct drm_devic
void drm_dev_ref(struct drm_device *dev);
void drm_dev_unref(struct drm_device *dev);
void drm_put_dev(struct drm_device *dev);
-void drm_unplug_dev(struct drm_device *dev);
+void drm_dev_unplug(struct drm_device *dev);
+
+/**
+ * drm_dev_is_unplugged - is a DRM device unplugged
+ * @dev: DRM device
+ *
+ * This function can be called to check whether a hotpluggable is unplugged.
+ * Unplugging itself is singalled through drm_dev_unplug(). If a device is
+ * unplugged, these two functions guarantee that any store before calling
+ * drm_dev_unplug() is visible to callers of this function after it completes
+ */
+static inline int drm_dev_is_unplugged(struct drm_device *dev)
+{
+ int ret = atomic_read(&dev->unplugged);
+ smp_rmb();
+ return ret;
+}
+
int drm_dev_set_unique(struct drm_device *dev, const char *name);