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Diffstat (limited to '')
| -rw-r--r-- | drivers/gpu/drm/drm_drv.c | 1083 |
1 files changed, 1083 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c new file mode 100644 index 000000000..d41a5eaa3 --- /dev/null +++ b/drivers/gpu/drm/drm_drv.c @@ -0,0 +1,1083 @@ +/* + * 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/pseudo_fs.h> +#include <linux/slab.h> +#include <linux/srcu.h> + +#include <drm/drm_cache.h> +#include <drm/drm_client.h> +#include <drm/drm_color_mgmt.h> +#include <drm/drm_drv.h> +#include <drm/drm_file.h> +#include <drm/drm_managed.h> +#include <drm/drm_mode_object.h> +#include <drm/drm_print.h> +#include <drm/drm_privacy_screen_machine.h> + +#include "drm_crtc_internal.h" +#include "drm_internal.h" +#include "drm_legacy.h" + +MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl"); +MODULE_DESCRIPTION("DRM shared core routines"); +MODULE_LICENSE("GPL and additional rights"); + +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; + +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 void drm_minor_alloc_release(struct drm_device *dev, void *data) +{ + struct drm_minor *minor = data; + unsigned long flags; + + WARN_ON(dev != minor->dev); + + 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); +} + +static int drm_minor_alloc(struct drm_device *dev, unsigned int type) +{ + struct drm_minor *minor; + unsigned long flags; + int r; + + minor = drmm_kzalloc(dev, 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) + return r; + + minor->index = r; + + r = drmm_add_action_or_reset(dev, drm_minor_alloc_release, minor); + if (r) + return r; + + minor->kdev = drm_sysfs_minor_alloc(minor); + if (IS_ERR(minor->kdev)) + return PTR_ERR(minor->kdev); + + *drm_minor_get_slot(dev, type) = minor; + return 0; +} + +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 and initialized with devm_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 initial output + * configuration plus obviously initialize all the corresponding hardware bits. + * 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 initializing 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 any allocation or resource which is visible to userspace must be + * released only when the final drm_dev_put() is called, and not when the + * driver is unbound from the underlying physical struct &device. Best to use + * &drm_device managed resources with drmm_add_action(), drmm_kmalloc() and + * related functions. + * + * devres managed resources like devm_kmalloc() can only be used for resources + * directly related to the underlying hardware device, and only used in code + * paths fully protected by drm_dev_enter() and drm_dev_exit(). + * + * Display driver example + * ~~~~~~~~~~~~~~~~~~~~~~ + * + * The following example shows a typical structure of a DRM display driver. + * The example focus on the probe() function and the other functions that is + * almost always present and serves as a demonstration of devm_drm_dev_alloc(). + * + * .. code-block:: c + * + * struct driver_device { + * struct drm_device drm; + * void *userspace_facing; + * struct clk *pclk; + * }; + * + * static const struct drm_driver driver_drm_driver = { + * [...] + * }; + * + * static int driver_probe(struct platform_device *pdev) + * { + * struct driver_device *priv; + * struct drm_device *drm; + * int ret; + * + * priv = devm_drm_dev_alloc(&pdev->dev, &driver_drm_driver, + * struct driver_device, drm); + * if (IS_ERR(priv)) + * return PTR_ERR(priv); + * drm = &priv->drm; + * + * ret = drmm_mode_config_init(drm); + * if (ret) + * return ret; + * + * priv->userspace_facing = drmm_kzalloc(..., GFP_KERNEL); + * if (!priv->userspace_facing) + * return -ENOMEM; + * + * priv->pclk = devm_clk_get(dev, "PCLK"); + * if (IS_ERR(priv->pclk)) + * return PTR_ERR(priv->pclk); + * + * // Further setup, display pipeline etc + * + * platform_set_drvdata(pdev, drm); + * + * drm_mode_config_reset(drm); + * + * ret = drm_dev_register(drm); + * if (ret) + * return ret; + * + * drm_fbdev_generic_setup(drm, 32); + * + * return 0; + * } + * + * // This function is called before the devm_ resources are released + * static int driver_remove(struct platform_device *pdev) + * { + * struct drm_device *drm = platform_get_drvdata(pdev); + * + * drm_dev_unregister(drm); + * drm_atomic_helper_shutdown(drm) + * + * return 0; + * } + * + * // This function is called on kernel restart and shutdown + * static void driver_shutdown(struct platform_device *pdev) + * { + * drm_atomic_helper_shutdown(platform_get_drvdata(pdev)); + * } + * + * static int __maybe_unused driver_pm_suspend(struct device *dev) + * { + * return drm_mode_config_helper_suspend(dev_get_drvdata(dev)); + * } + * + * static int __maybe_unused driver_pm_resume(struct device *dev) + * { + * drm_mode_config_helper_resume(dev_get_drvdata(dev)); + * + * return 0; + * } + * + * static const struct dev_pm_ops driver_pm_ops = { + * SET_SYSTEM_SLEEP_PM_OPS(driver_pm_suspend, driver_pm_resume) + * }; + * + * static struct platform_driver driver_driver = { + * .driver = { + * [...] + * .pm = &driver_pm_ops, + * }, + * .probe = driver_probe, + * .remove = driver_remove, + * .shutdown = driver_shutdown, + * }; + * module_platform_driver(driver_driver); + * + * Drivers that want to support device unplugging (USB, DT overlay unload) should + * use drm_dev_unplug() instead of drm_dev_unregister(). The driver must protect + * regions that is accessing device resources to prevent use after they're + * released. This is done using drm_dev_enter() and drm_dev_exit(). There is one + * shortcoming however, drm_dev_unplug() marks the drm_device as unplugged before + * drm_atomic_helper_shutdown() is called. This means that if the disable code + * paths are protected, they will not run on regular driver module unload, + * possibly leaving the hardware enabled. + */ + +/** + * 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); + + /* Clear all CPU mappings pointing to this device */ + unmap_mapping_range(dev->anon_inode->i_mapping, 0, 0, 1); +} +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 int drm_fs_init_fs_context(struct fs_context *fc) +{ + return init_pseudo(fc, 0x010203ff) ? 0 : -ENOMEM; +} + +static struct file_system_type drm_fs_type = { + .name = "drm", + .owner = THIS_MODULE, + .init_fs_context = drm_fs_init_fs_context, + .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); + } +} + +/** + * DOC: component helper usage recommendations + * + * DRM drivers that drive hardware where a logical device consists of a pile of + * independent hardware blocks are recommended to use the :ref:`component helper + * library<component>`. For consistency and better options for code reuse the + * following guidelines apply: + * + * - The entire device initialization procedure should be run from the + * &component_master_ops.master_bind callback, starting with + * devm_drm_dev_alloc(), then binding all components with + * component_bind_all() and finishing with drm_dev_register(). + * + * - The opaque pointer passed to all components through component_bind_all() + * should point at &struct drm_device of the device instance, not some driver + * specific private structure. + * + * - The component helper fills the niche where further standardization of + * interfaces is not practical. When there already is, or will be, a + * standardized interface like &drm_bridge or &drm_panel, providing its own + * functions to find such components at driver load time, like + * drm_of_find_panel_or_bridge(), then the component helper should not be + * used. + */ + +static void drm_dev_init_release(struct drm_device *dev, void *res) +{ + drm_legacy_ctxbitmap_cleanup(dev); + drm_legacy_remove_map_hash(dev); + drm_fs_inode_free(dev->anon_inode); + + put_device(dev->dev); + /* Prevent use-after-free in drm_managed_release when debugging is + * enabled. Slightly awkward, but can't really be helped. */ + dev->dev = NULL; + mutex_destroy(&dev->master_mutex); + mutex_destroy(&dev->clientlist_mutex); + mutex_destroy(&dev->filelist_mutex); + mutex_destroy(&dev->struct_mutex); + drm_legacy_destroy_members(dev); +} + +static int drm_dev_init(struct drm_device *dev, + const struct drm_driver *driver, + struct device *parent) +{ + struct inode *inode; + int ret; + + if (!drm_core_init_complete) { + DRM_ERROR("DRM core is not initialized\n"); + return -ENODEV; + } + + if (WARN_ON(!parent)) + return -EINVAL; + + kref_init(&dev->ref); + dev->dev = get_device(parent); + dev->driver = driver; + + INIT_LIST_HEAD(&dev->managed.resources); + spin_lock_init(&dev->managed.lock); + + /* no per-device feature limits by default */ + dev->driver_features = ~0u; + + drm_legacy_init_members(dev); + INIT_LIST_HEAD(&dev->filelist); + INIT_LIST_HEAD(&dev->filelist_internal); + INIT_LIST_HEAD(&dev->clientlist); + INIT_LIST_HEAD(&dev->vblank_event_list); + + spin_lock_init(&dev->event_lock); + mutex_init(&dev->struct_mutex); + mutex_init(&dev->filelist_mutex); + mutex_init(&dev->clientlist_mutex); + mutex_init(&dev->master_mutex); + + ret = drmm_add_action_or_reset(dev, drm_dev_init_release, NULL); + if (ret) + return ret; + + inode = drm_fs_inode_new(); + if (IS_ERR(inode)) { + ret = PTR_ERR(inode); + DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret); + goto err; + } + + dev->anon_inode = inode; + + if (drm_core_check_feature(dev, DRIVER_RENDER)) { + ret = drm_minor_alloc(dev, DRM_MINOR_RENDER); + if (ret) + goto err; + } + + ret = drm_minor_alloc(dev, DRM_MINOR_PRIMARY); + if (ret) + goto err; + + ret = drm_legacy_create_map_hash(dev); + if (ret) + goto err; + + 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; + } + } + + ret = drm_dev_set_unique(dev, dev_name(parent)); + if (ret) + goto err; + + return 0; + +err: + drm_managed_release(dev); + + return ret; +} + +static void devm_drm_dev_init_release(void *data) +{ + drm_dev_put(data); +} + +static int devm_drm_dev_init(struct device *parent, + struct drm_device *dev, + const struct drm_driver *driver) +{ + int ret; + + ret = drm_dev_init(dev, driver, parent); + if (ret) + return ret; + + return devm_add_action_or_reset(parent, + devm_drm_dev_init_release, dev); +} + +void *__devm_drm_dev_alloc(struct device *parent, + const struct drm_driver *driver, + size_t size, size_t offset) +{ + void *container; + struct drm_device *drm; + int ret; + + container = kzalloc(size, GFP_KERNEL); + if (!container) + return ERR_PTR(-ENOMEM); + + drm = container + offset; + ret = devm_drm_dev_init(parent, drm, driver); + if (ret) { + kfree(container); + return ERR_PTR(ret); + } + drmm_add_final_kfree(drm, container); + + return container; +} +EXPORT_SYMBOL(__devm_drm_dev_alloc); + +/** + * drm_dev_alloc - Allocate new DRM device + * @driver: DRM driver to allocate device for + * @parent: Parent device object + * + * This is the deprecated version of devm_drm_dev_alloc(), which does not support + * subclassing through embedding the struct &drm_device in a driver private + * structure, and which does not support automatic cleanup through devres. + * + * RETURNS: + * Pointer to new DRM device, or ERR_PTR on failure. + */ +struct drm_device *drm_dev_alloc(const 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); + } + + drmm_add_final_kfree(dev, dev); + + 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); + + drm_managed_release(dev); + + kfree(dev->managed.final_kfree); +} + +/** + * 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); + +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 initialized via drm_dev_init() + * 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) +{ + const struct drm_driver *driver = dev->driver; + int ret; + + if (!driver->load) + drm_mode_config_validate(dev); + + WARN_ON(!dev->managed.final_kfree); + + if (drm_dev_needs_global_mutex(dev)) + 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)) { + ret = drm_modeset_register_all(dev); + if (ret) + goto err_unload; + } + + 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_unload: + if (dev->driver->unload) + dev->driver->unload(dev); +err_minors: + remove_compat_control_link(dev); + drm_minor_unregister(dev, DRM_MINOR_PRIMARY); + drm_minor_unregister(dev, DRM_MINOR_RENDER); +out_unlock: + if (drm_dev_needs_global_mutex(dev)) + 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) +{ + 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); + + drm_legacy_pci_agp_destroy(dev); + drm_legacy_rmmaps(dev); + + 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. This is + * already done by drm_dev_init(), drivers should only override the default + * unique name for backwards compatibility reasons. + * + * Return: 0 on success or a negative error code on failure. + */ +int drm_dev_set_unique(struct drm_device *dev, const char *name) +{ + drmm_kfree(dev, dev->unique); + dev->unique = drmm_kstrdup(dev, 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"); + + minor = drm_minor_acquire(iminor(inode)); + if (IS_ERR(minor)) + return PTR_ERR(minor); + + new_fops = fops_get(minor->dev->driver->fops); + if (!new_fops) { + err = -ENODEV; + goto out; + } + + replace_fops(filp, new_fops); + if (filp->f_op->open) + err = filp->f_op->open(inode, filp); + else + err = 0; + +out: + drm_minor_release(minor); + + 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) +{ + drm_privacy_screen_lookup_exit(); + unregister_chrdev(DRM_MAJOR, "drm"); + debugfs_remove(drm_debugfs_root); + drm_sysfs_destroy(); + idr_destroy(&drm_minors_idr); + drm_connector_ida_destroy(); +} + +static int __init drm_core_init(void) +{ + int ret; + + drm_connector_ida_init(); + idr_init(&drm_minors_idr); + drm_memcpy_init_early(); + + 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); + + ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops); + if (ret < 0) + goto error; + + drm_privacy_screen_lookup_init(); + + 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); |