Permalink
Fetching contributors…
Cannot retrieve contributors at this time
1015 lines (868 sloc) 27.9 KB
/*
* Created: Fri Jan 19 10:48:35 2001 by faith@acm.org
*
* Copyright 2001 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* Author Rickard E. (Rik) Faith <faith@valinux.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include <linux/debugfs.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/mount.h>
#include <linux/slab.h>
#include <linux/srcu.h>
#include <drm/drm_client.h>
#include <drm/drm_drv.h>
#include <drm/drmP.h>
#include "drm_crtc_internal.h"
#include "drm_legacy.h"
#include "drm_internal.h"
#include "drm_crtc_internal.h"
/*
* drm_debug: Enable debug output.
* Bitmask of DRM_UT_x. See include/drm/drmP.h for details.
*/
unsigned int drm_debug = 0;
EXPORT_SYMBOL(drm_debug);
MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl");
MODULE_DESCRIPTION("DRM shared core routines");
MODULE_LICENSE("GPL and additional rights");
MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug category.\n"
"\t\tBit 0 (0x01) will enable CORE messages (drm core code)\n"
"\t\tBit 1 (0x02) will enable DRIVER messages (drm controller code)\n"
"\t\tBit 2 (0x04) will enable KMS messages (modesetting code)\n"
"\t\tBit 3 (0x08) will enable PRIME messages (prime code)\n"
"\t\tBit 4 (0x10) will enable ATOMIC messages (atomic code)\n"
"\t\tBit 5 (0x20) will enable VBL messages (vblank code)\n"
"\t\tBit 7 (0x80) will enable LEASE messages (leasing code)\n"
"\t\tBit 8 (0x100) will enable DP messages (displayport code)");
module_param_named(debug, drm_debug, int, 0600);
static DEFINE_SPINLOCK(drm_minor_lock);
static struct idr drm_minors_idr;
/*
* If the drm core fails to init for whatever reason,
* we should prevent any drivers from registering with it.
* It's best to check this at drm_dev_init(), as some drivers
* prefer to embed struct drm_device into their own device
* structure and call drm_dev_init() themselves.
*/
static bool drm_core_init_complete = false;
static struct dentry *drm_debugfs_root;
DEFINE_STATIC_SRCU(drm_unplug_srcu);
/*
* DRM Minors
* A DRM device can provide several char-dev interfaces on the DRM-Major. Each
* of them is represented by a drm_minor object. Depending on the capabilities
* of the device-driver, different interfaces are registered.
*
* Minors can be accessed via dev->$minor_name. This pointer is either
* NULL or a valid drm_minor pointer and stays valid as long as the device is
* valid. This means, DRM minors have the same life-time as the underlying
* device. However, this doesn't mean that the minor is active. Minors are
* registered and unregistered dynamically according to device-state.
*/
static struct drm_minor **drm_minor_get_slot(struct drm_device *dev,
unsigned int type)
{
switch (type) {
case DRM_MINOR_PRIMARY:
return &dev->primary;
case DRM_MINOR_RENDER:
return &dev->render;
default:
BUG();
}
}
static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
{
struct drm_minor *minor;
unsigned long flags;
int r;
minor = kzalloc(sizeof(*minor), GFP_KERNEL);
if (!minor)
return -ENOMEM;
minor->type = type;
minor->dev = dev;
idr_preload(GFP_KERNEL);
spin_lock_irqsave(&drm_minor_lock, flags);
r = idr_alloc(&drm_minors_idr,
NULL,
64 * type,
64 * (type + 1),
GFP_NOWAIT);
spin_unlock_irqrestore(&drm_minor_lock, flags);
idr_preload_end();
if (r < 0)
goto err_free;
minor->index = r;
minor->kdev = drm_sysfs_minor_alloc(minor);
if (IS_ERR(minor->kdev)) {
r = PTR_ERR(minor->kdev);
goto err_index;
}
*drm_minor_get_slot(dev, type) = minor;
return 0;
err_index:
spin_lock_irqsave(&drm_minor_lock, flags);
idr_remove(&drm_minors_idr, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
err_free:
kfree(minor);
return r;
}
static void drm_minor_free(struct drm_device *dev, unsigned int type)
{
struct drm_minor **slot, *minor;
unsigned long flags;
slot = drm_minor_get_slot(dev, type);
minor = *slot;
if (!minor)
return;
put_device(minor->kdev);
spin_lock_irqsave(&drm_minor_lock, flags);
idr_remove(&drm_minors_idr, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
kfree(minor);
*slot = NULL;
}
static int drm_minor_register(struct drm_device *dev, unsigned int type)
{
struct drm_minor *minor;
unsigned long flags;
int ret;
DRM_DEBUG("\n");
minor = *drm_minor_get_slot(dev, type);
if (!minor)
return 0;
ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root);
if (ret) {
DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
goto err_debugfs;
}
ret = device_add(minor->kdev);
if (ret)
goto err_debugfs;
/* replace NULL with @minor so lookups will succeed from now on */
spin_lock_irqsave(&drm_minor_lock, flags);
idr_replace(&drm_minors_idr, minor, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
DRM_DEBUG("new minor registered %d\n", minor->index);
return 0;
err_debugfs:
drm_debugfs_cleanup(minor);
return ret;
}
static void drm_minor_unregister(struct drm_device *dev, unsigned int type)
{
struct drm_minor *minor;
unsigned long flags;
minor = *drm_minor_get_slot(dev, type);
if (!minor || !device_is_registered(minor->kdev))
return;
/* replace @minor with NULL so lookups will fail from now on */
spin_lock_irqsave(&drm_minor_lock, flags);
idr_replace(&drm_minors_idr, NULL, minor->index);
spin_unlock_irqrestore(&drm_minor_lock, flags);
device_del(minor->kdev);
dev_set_drvdata(minor->kdev, NULL); /* safety belt */
drm_debugfs_cleanup(minor);
}
/*
* Looks up the given minor-ID and returns the respective DRM-minor object. The
* refence-count of the underlying device is increased so you must release this
* object with drm_minor_release().
*
* As long as you hold this minor, it is guaranteed that the object and the
* minor->dev pointer will stay valid! However, the device may get unplugged and
* unregistered while you hold the minor.
*/
struct drm_minor *drm_minor_acquire(unsigned int minor_id)
{
struct drm_minor *minor;
unsigned long flags;
spin_lock_irqsave(&drm_minor_lock, flags);
minor = idr_find(&drm_minors_idr, minor_id);
if (minor)
drm_dev_get(minor->dev);
spin_unlock_irqrestore(&drm_minor_lock, flags);
if (!minor) {
return ERR_PTR(-ENODEV);
} else if (drm_dev_is_unplugged(minor->dev)) {
drm_dev_put(minor->dev);
return ERR_PTR(-ENODEV);
}
return minor;
}
void drm_minor_release(struct drm_minor *minor)
{
drm_dev_put(minor->dev);
}
/**
* DOC: driver instance overview
*
* A device instance for a drm driver is represented by &struct drm_device. This
* is allocated with drm_dev_alloc(), usually from bus-specific ->probe()
* callbacks implemented by the driver. The driver then needs to initialize all
* the various subsystems for the drm device like memory management, vblank
* handling, modesetting support and intial output configuration plus obviously
* initialize all the corresponding hardware bits. An important part of this is
* also calling drm_dev_set_unique() to set the userspace-visible unique name of
* this device instance. Finally when everything is up and running and ready for
* userspace the device instance can be published using drm_dev_register().
*
* There is also deprecated support for initalizing device instances using
* bus-specific helpers and the &drm_driver.load callback. But due to
* backwards-compatibility needs the device instance have to be published too
* early, which requires unpretty global locking to make safe and is therefore
* only support for existing drivers not yet converted to the new scheme.
*
* When cleaning up a device instance everything needs to be done in reverse:
* First unpublish the device instance with drm_dev_unregister(). Then clean up
* any other resources allocated at device initialization and drop the driver's
* reference to &drm_device using drm_dev_put().
*
* Note that the lifetime rules for &drm_device instance has still a lot of
* historical baggage. Hence use the reference counting provided by
* drm_dev_get() and drm_dev_put() only carefully.
*
* It is recommended that drivers embed &struct drm_device into their own device
* structure, which is supported through drm_dev_init().
*/
/**
* drm_put_dev - Unregister and release a DRM device
* @dev: DRM device
*
* Called at module unload time or when a PCI device is unplugged.
*
* Cleans up all DRM device, calling drm_lastclose().
*
* Note: Use of this function is deprecated. It will eventually go away
* completely. Please use drm_dev_unregister() and drm_dev_put() explicitly
* instead to make sure that the device isn't userspace accessible any more
* while teardown is in progress, ensuring that userspace can't access an
* inconsistent state.
*/
void drm_put_dev(struct drm_device *dev)
{
DRM_DEBUG("\n");
if (!dev) {
DRM_ERROR("cleanup called no dev\n");
return;
}
drm_dev_unregister(dev);
drm_dev_put(dev);
}
EXPORT_SYMBOL(drm_put_dev);
/**
* drm_dev_enter - Enter device critical section
* @dev: DRM device
* @idx: Pointer to index that will be passed to the matching drm_dev_exit()
*
* This function marks and protects the beginning of a section that should not
* be entered after the device has been unplugged. The section end is marked
* with drm_dev_exit(). Calls to this function can be nested.
*
* Returns:
* True if it is OK to enter the section, false otherwise.
*/
bool drm_dev_enter(struct drm_device *dev, int *idx)
{
*idx = srcu_read_lock(&drm_unplug_srcu);
if (dev->unplugged) {
srcu_read_unlock(&drm_unplug_srcu, *idx);
return false;
}
return true;
}
EXPORT_SYMBOL(drm_dev_enter);
/**
* drm_dev_exit - Exit device critical section
* @idx: index returned from drm_dev_enter()
*
* This function marks the end of a section that should not be entered after
* the device has been unplugged.
*/
void drm_dev_exit(int idx)
{
srcu_read_unlock(&drm_unplug_srcu, idx);
}
EXPORT_SYMBOL(drm_dev_exit);
/**
* 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_enter() and
* drm_dev_exit() to protect device resources in a race free manner. 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)
{
/*
* After synchronizing any critical read section is guaranteed to see
* the new value of ->unplugged, and any critical section which might
* still have seen the old value of ->unplugged is guaranteed to have
* finished.
*/
dev->unplugged = true;
synchronize_srcu(&drm_unplug_srcu);
drm_dev_unregister(dev);
mutex_lock(&drm_global_mutex);
if (dev->open_count == 0)
drm_dev_put(dev);
mutex_unlock(&drm_global_mutex);
}
EXPORT_SYMBOL(drm_dev_unplug);
/*
* DRM internal mount
* We want to be able to allocate our own "struct address_space" to control
* memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
* stand-alone address_space objects, so we need an underlying inode. As there
* is no way to allocate an independent inode easily, we need a fake internal
* VFS mount-point.
*
* The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
* frees it again. You are allowed to use iget() and iput() to get references to
* the inode. But each drm_fs_inode_new() call must be paired with exactly one
* drm_fs_inode_free() call (which does not have to be the last iput()).
* We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
* between multiple inode-users. You could, technically, call
* iget() + drm_fs_inode_free() directly after alloc and sometime later do an
* iput(), but this way you'd end up with a new vfsmount for each inode.
*/
static int drm_fs_cnt;
static struct vfsmount *drm_fs_mnt;
static const struct dentry_operations drm_fs_dops = {
.d_dname = simple_dname,
};
static const struct super_operations drm_fs_sops = {
.statfs = simple_statfs,
};
static struct dentry *drm_fs_mount(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data)
{
return mount_pseudo(fs_type,
"drm:",
&drm_fs_sops,
&drm_fs_dops,
0x010203ff);
}
static struct file_system_type drm_fs_type = {
.name = "drm",
.owner = THIS_MODULE,
.mount = drm_fs_mount,
.kill_sb = kill_anon_super,
};
static struct inode *drm_fs_inode_new(void)
{
struct inode *inode;
int r;
r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt);
if (r < 0) {
DRM_ERROR("Cannot mount pseudo fs: %d\n", r);
return ERR_PTR(r);
}
inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);
if (IS_ERR(inode))
simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
return inode;
}
static void drm_fs_inode_free(struct inode *inode)
{
if (inode) {
iput(inode);
simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
}
}
/**
* drm_dev_init - Initialise new DRM device
* @dev: DRM device
* @driver: DRM driver
* @parent: Parent device object
*
* Initialize a new DRM device. No device registration is done.
* Call drm_dev_register() to advertice the device to user space and register it
* with other core subsystems. This should be done last in the device
* initialization sequence to make sure userspace can't access an inconsistent
* state.
*
* The initial ref-count of the object is 1. Use drm_dev_get() and
* drm_dev_put() to take and drop further ref-counts.
*
* Note that for purely virtual devices @parent can be NULL.
*
* Drivers that do not want to allocate their own device struct
* embedding &struct drm_device can call drm_dev_alloc() instead. For drivers
* that do embed &struct drm_device it must be placed first in the overall
* structure, and the overall structure must be allocated using kmalloc(): The
* drm core's release function unconditionally calls kfree() on the @dev pointer
* when the final reference is released. To override this behaviour, and so
* allow embedding of the drm_device inside the driver's device struct at an
* arbitrary offset, you must supply a &drm_driver.release callback and control
* the finalization explicitly.
*
* RETURNS:
* 0 on success, or error code on failure.
*/
int drm_dev_init(struct drm_device *dev,
struct drm_driver *driver,
struct device *parent)
{
int ret;
if (!drm_core_init_complete) {
DRM_ERROR("DRM core is not initialized\n");
return -ENODEV;
}
kref_init(&dev->ref);
dev->dev = parent;
dev->driver = driver;
INIT_LIST_HEAD(&dev->filelist);
INIT_LIST_HEAD(&dev->filelist_internal);
INIT_LIST_HEAD(&dev->clientlist);
INIT_LIST_HEAD(&dev->ctxlist);
INIT_LIST_HEAD(&dev->vmalist);
INIT_LIST_HEAD(&dev->maplist);
INIT_LIST_HEAD(&dev->vblank_event_list);
spin_lock_init(&dev->buf_lock);
spin_lock_init(&dev->event_lock);
mutex_init(&dev->struct_mutex);
mutex_init(&dev->filelist_mutex);
mutex_init(&dev->clientlist_mutex);
mutex_init(&dev->ctxlist_mutex);
mutex_init(&dev->master_mutex);
dev->anon_inode = drm_fs_inode_new();
if (IS_ERR(dev->anon_inode)) {
ret = PTR_ERR(dev->anon_inode);
DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret);
goto err_free;
}
if (drm_core_check_feature(dev, DRIVER_RENDER)) {
ret = drm_minor_alloc(dev, DRM_MINOR_RENDER);
if (ret)
goto err_minors;
}
ret = drm_minor_alloc(dev, DRM_MINOR_PRIMARY);
if (ret)
goto err_minors;
ret = drm_ht_create(&dev->map_hash, 12);
if (ret)
goto err_minors;
drm_legacy_ctxbitmap_init(dev);
if (drm_core_check_feature(dev, DRIVER_GEM)) {
ret = drm_gem_init(dev);
if (ret) {
DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
goto err_ctxbitmap;
}
}
/* Use the parent device name as DRM device unique identifier, but fall
* back to the driver name for virtual devices like vgem. */
ret = drm_dev_set_unique(dev, parent ? dev_name(parent) : driver->name);
if (ret)
goto err_setunique;
return 0;
err_setunique:
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_destroy(dev);
err_ctxbitmap:
drm_legacy_ctxbitmap_cleanup(dev);
drm_ht_remove(&dev->map_hash);
err_minors:
drm_minor_free(dev, DRM_MINOR_PRIMARY);
drm_minor_free(dev, DRM_MINOR_RENDER);
drm_fs_inode_free(dev->anon_inode);
err_free:
mutex_destroy(&dev->master_mutex);
mutex_destroy(&dev->ctxlist_mutex);
mutex_destroy(&dev->clientlist_mutex);
mutex_destroy(&dev->filelist_mutex);
mutex_destroy(&dev->struct_mutex);
return ret;
}
EXPORT_SYMBOL(drm_dev_init);
/**
* drm_dev_fini - Finalize a dead DRM device
* @dev: DRM device
*
* Finalize a dead DRM device. This is the converse to drm_dev_init() and
* frees up all data allocated by it. All driver private data should be
* finalized first. Note that this function does not free the @dev, that is
* left to the caller.
*
* The ref-count of @dev must be zero, and drm_dev_fini() should only be called
* from a &drm_driver.release callback.
*/
void drm_dev_fini(struct drm_device *dev)
{
drm_vblank_cleanup(dev);
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_destroy(dev);
drm_legacy_ctxbitmap_cleanup(dev);
drm_ht_remove(&dev->map_hash);
drm_fs_inode_free(dev->anon_inode);
drm_minor_free(dev, DRM_MINOR_PRIMARY);
drm_minor_free(dev, DRM_MINOR_RENDER);
mutex_destroy(&dev->master_mutex);
mutex_destroy(&dev->ctxlist_mutex);
mutex_destroy(&dev->clientlist_mutex);
mutex_destroy(&dev->filelist_mutex);
mutex_destroy(&dev->struct_mutex);
kfree(dev->unique);
}
EXPORT_SYMBOL(drm_dev_fini);
/**
* drm_dev_alloc - Allocate new DRM device
* @driver: DRM driver to allocate device for
* @parent: Parent device object
*
* Allocate and initialize a new DRM device. No device registration is done.
* Call drm_dev_register() to advertice the device to user space and register it
* with other core subsystems. This should be done last in the device
* initialization sequence to make sure userspace can't access an inconsistent
* state.
*
* The initial ref-count of the object is 1. Use drm_dev_get() and
* drm_dev_put() to take and drop further ref-counts.
*
* Note that for purely virtual devices @parent can be NULL.
*
* Drivers that wish to subclass or embed &struct drm_device into their
* own struct should look at using drm_dev_init() instead.
*
* RETURNS:
* Pointer to new DRM device, or ERR_PTR on failure.
*/
struct drm_device *drm_dev_alloc(struct drm_driver *driver,
struct device *parent)
{
struct drm_device *dev;
int ret;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return ERR_PTR(-ENOMEM);
ret = drm_dev_init(dev, driver, parent);
if (ret) {
kfree(dev);
return ERR_PTR(ret);
}
return dev;
}
EXPORT_SYMBOL(drm_dev_alloc);
static void drm_dev_release(struct kref *ref)
{
struct drm_device *dev = container_of(ref, struct drm_device, ref);
if (dev->driver->release) {
dev->driver->release(dev);
} else {
drm_dev_fini(dev);
kfree(dev);
}
}
/**
* drm_dev_get - Take reference of a DRM device
* @dev: device to take reference of or NULL
*
* This increases the ref-count of @dev by one. You *must* already own a
* reference when calling this. Use drm_dev_put() to drop this reference
* again.
*
* This function never fails. However, this function does not provide *any*
* guarantee whether the device is alive or running. It only provides a
* reference to the object and the memory associated with it.
*/
void drm_dev_get(struct drm_device *dev)
{
if (dev)
kref_get(&dev->ref);
}
EXPORT_SYMBOL(drm_dev_get);
/**
* drm_dev_put - Drop reference of a DRM device
* @dev: device to drop reference of or NULL
*
* This decreases the ref-count of @dev by one. The device is destroyed if the
* ref-count drops to zero.
*/
void drm_dev_put(struct drm_device *dev)
{
if (dev)
kref_put(&dev->ref, drm_dev_release);
}
EXPORT_SYMBOL(drm_dev_put);
/**
* drm_dev_unref - Drop reference of a DRM device
* @dev: device to drop reference of or NULL
*
* This is a compatibility alias for drm_dev_put() and should not be used by new
* code.
*/
void drm_dev_unref(struct drm_device *dev)
{
drm_dev_put(dev);
}
EXPORT_SYMBOL(drm_dev_unref);
static int create_compat_control_link(struct drm_device *dev)
{
struct drm_minor *minor;
char *name;
int ret;
if (!drm_core_check_feature(dev, DRIVER_MODESET))
return 0;
minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
if (!minor)
return 0;
/*
* Some existing userspace out there uses the existing of the controlD*
* sysfs files to figure out whether it's a modeset driver. It only does
* readdir, hence a symlink is sufficient (and the least confusing
* option). Otherwise controlD* is entirely unused.
*
* Old controlD chardev have been allocated in the range
* 64-127.
*/
name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
if (!name)
return -ENOMEM;
ret = sysfs_create_link(minor->kdev->kobj.parent,
&minor->kdev->kobj,
name);
kfree(name);
return ret;
}
static void remove_compat_control_link(struct drm_device *dev)
{
struct drm_minor *minor;
char *name;
if (!drm_core_check_feature(dev, DRIVER_MODESET))
return;
minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY);
if (!minor)
return;
name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64);
if (!name)
return;
sysfs_remove_link(minor->kdev->kobj.parent, name);
kfree(name);
}
/**
* drm_dev_register - Register DRM device
* @dev: Device to register
* @flags: Flags passed to the driver's .load() function
*
* Register the DRM device @dev with the system, advertise device to user-space
* and start normal device operation. @dev must be allocated via drm_dev_alloc()
* previously.
*
* Never call this twice on any device!
*
* NOTE: To ensure backward compatibility with existing drivers method this
* function calls the &drm_driver.load method after registering the device
* nodes, creating race conditions. Usage of the &drm_driver.load methods is
* therefore deprecated, drivers must perform all initialization before calling
* drm_dev_register().
*
* RETURNS:
* 0 on success, negative error code on failure.
*/
int drm_dev_register(struct drm_device *dev, unsigned long flags)
{
struct drm_driver *driver = dev->driver;
int ret;
mutex_lock(&drm_global_mutex);
ret = drm_minor_register(dev, DRM_MINOR_RENDER);
if (ret)
goto err_minors;
ret = drm_minor_register(dev, DRM_MINOR_PRIMARY);
if (ret)
goto err_minors;
ret = create_compat_control_link(dev);
if (ret)
goto err_minors;
dev->registered = true;
if (dev->driver->load) {
ret = dev->driver->load(dev, flags);
if (ret)
goto err_minors;
}
if (drm_core_check_feature(dev, DRIVER_MODESET))
drm_modeset_register_all(dev);
ret = 0;
DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n",
driver->name, driver->major, driver->minor,
driver->patchlevel, driver->date,
dev->dev ? dev_name(dev->dev) : "virtual device",
dev->primary->index);
goto out_unlock;
err_minors:
remove_compat_control_link(dev);
drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
drm_minor_unregister(dev, DRM_MINOR_RENDER);
out_unlock:
mutex_unlock(&drm_global_mutex);
return ret;
}
EXPORT_SYMBOL(drm_dev_register);
/**
* drm_dev_unregister - Unregister DRM device
* @dev: Device to unregister
*
* Unregister the DRM device from the system. This does the reverse of
* drm_dev_register() but does not deallocate the device. The caller must call
* drm_dev_put() 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.
*/
void drm_dev_unregister(struct drm_device *dev)
{
struct drm_map_list *r_list, *list_temp;
if (drm_core_check_feature(dev, DRIVER_LEGACY))
drm_lastclose(dev);
dev->registered = false;
drm_client_dev_unregister(dev);
if (drm_core_check_feature(dev, DRIVER_MODESET))
drm_modeset_unregister_all(dev);
if (dev->driver->unload)
dev->driver->unload(dev);
if (dev->agp)
drm_pci_agp_destroy(dev);
list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head)
drm_legacy_rmmap(dev, r_list->map);
remove_compat_control_link(dev);
drm_minor_unregister(dev, DRM_MINOR_PRIMARY);
drm_minor_unregister(dev, DRM_MINOR_RENDER);
}
EXPORT_SYMBOL(drm_dev_unregister);
/**
* drm_dev_set_unique - Set the unique name of a DRM device
* @dev: device of which to set the unique name
* @name: unique name
*
* Sets the unique name of a DRM device using the specified string. Drivers
* can use this at driver probe time if the unique name of the devices they
* drive is static.
*
* Return: 0 on success or a negative error code on failure.
*/
int drm_dev_set_unique(struct drm_device *dev, const char *name)
{
kfree(dev->unique);
dev->unique = kstrdup(name, GFP_KERNEL);
return dev->unique ? 0 : -ENOMEM;
}
EXPORT_SYMBOL(drm_dev_set_unique);
/*
* DRM Core
* The DRM core module initializes all global DRM objects and makes them
* available to drivers. Once setup, drivers can probe their respective
* devices.
* Currently, core management includes:
* - The "DRM-Global" key/value database
* - Global ID management for connectors
* - DRM major number allocation
* - DRM minor management
* - DRM sysfs class
* - DRM debugfs root
*
* Furthermore, the DRM core provides dynamic char-dev lookups. For each
* interface registered on a DRM device, you can request minor numbers from DRM
* core. DRM core takes care of major-number management and char-dev
* registration. A stub ->open() callback forwards any open() requests to the
* registered minor.
*/
static int drm_stub_open(struct inode *inode, struct file *filp)
{
const struct file_operations *new_fops;
struct drm_minor *minor;
int err;
DRM_DEBUG("\n");
mutex_lock(&drm_global_mutex);
minor = drm_minor_acquire(iminor(inode));
if (IS_ERR(minor)) {
err = PTR_ERR(minor);
goto out_unlock;
}
new_fops = fops_get(minor->dev->driver->fops);
if (!new_fops) {
err = -ENODEV;
goto out_release;
}
replace_fops(filp, new_fops);
if (filp->f_op->open)
err = filp->f_op->open(inode, filp);
else
err = 0;
out_release:
drm_minor_release(minor);
out_unlock:
mutex_unlock(&drm_global_mutex);
return err;
}
static const struct file_operations drm_stub_fops = {
.owner = THIS_MODULE,
.open = drm_stub_open,
.llseek = noop_llseek,
};
static void drm_core_exit(void)
{
unregister_chrdev(DRM_MAJOR, "drm");
debugfs_remove(drm_debugfs_root);
drm_sysfs_destroy();
idr_destroy(&drm_minors_idr);
drm_connector_ida_destroy();
drm_global_release();
}
static int __init drm_core_init(void)
{
int ret;
drm_global_init();
drm_connector_ida_init();
idr_init(&drm_minors_idr);
ret = drm_sysfs_init();
if (ret < 0) {
DRM_ERROR("Cannot create DRM class: %d\n", ret);
goto error;
}
drm_debugfs_root = debugfs_create_dir("dri", NULL);
if (!drm_debugfs_root) {
ret = -ENOMEM;
DRM_ERROR("Cannot create debugfs-root: %d\n", ret);
goto error;
}
ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops);
if (ret < 0)
goto error;
drm_core_init_complete = true;
DRM_DEBUG("Initialized\n");
return 0;
error:
drm_core_exit();
return ret;
}
module_init(drm_core_init);
module_exit(drm_core_exit);