/* * 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/bitops.h> #include <linux/cgroup_dmem.h> #include <linux/debugfs.h> #include <linux/export.h> #include <linux/fs.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/mount.h> #include <linux/pseudo_fs.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/sprintf.h> #include <linux/srcu.h> #include <linux/xarray.h> #include <drm/drm_accel.h> #include <drm/drm_bridge.h> #include <drm/drm_cache.h> #include <drm/drm_client_event.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_panic.h> #include <drm/drm_print.h> #include <drm/drm_privacy_screen_machine.h> #include "drm_crtc_internal.h" #include "drm_internal.h" MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl"); MODULE_DESCRIPTION("DRM shared core routines"); MODULE_LICENSE("GPL and additional rights"); DEFINE_XARRAY_ALLOC(drm_minors_xa); /* * 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; 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 xarray *drm_minor_get_xa(enum drm_minor_type type) { if (type == DRM_MINOR_PRIMARY || type == DRM_MINOR_RENDER) return &drm_minors_xa; #if IS_ENABLED(CONFIG_DRM_ACCEL) else if (type == DRM_MINOR_ACCEL) return &accel_minors_xa; #endif else return ERR_PTR(-EOPNOTSUPP); } static struct drm_minor **drm_minor_get_slot(struct drm_device *dev, enum drm_minor_type type) { switch (type) { case DRM_MINOR_PRIMARY: return &dev->primary; case DRM_MINOR_RENDER: return &dev->render; case DRM_MINOR_ACCEL: return &dev->accel; default: BUG(); } } static void drm_minor_alloc_release(struct drm_device *dev, void *data) { struct drm_minor *minor = data; WARN_ON(dev != minor->dev); put_device(minor->kdev); xa_erase(drm_minor_get_xa(minor->type), minor->index); } /* * DRM used to support 64 devices, for backwards compatibility we need to maintain the * minor allocation scheme where minors 0-63 are primary nodes, 64-127 are control nodes, * and 128-191 are render nodes. * After reaching the limit, we're allocating minors dynamically - first-come, first-serve. * Accel nodes are using a distinct major, so the minors are allocated in continuous 0-MAX * range. */ #define DRM_MINOR_LIMIT(t) ({ \ typeof(t) _t = (t); \ _t == DRM_MINOR_ACCEL ? XA_LIMIT(0, ACCEL_MAX_MINORS) : XA_LIMIT(64 * _t, 64 * _t + 63); \ }) #define DRM_EXTENDED_MINOR_LIMIT XA_LIMIT(192, (1 << MINORBITS) - 1) static int drm_minor_alloc(struct drm_device *dev, enum drm_minor_type type) { struct drm_minor *minor; int r; minor = drmm_kzalloc(dev, sizeof(*minor), GFP_KERNEL); if (!minor) return -ENOMEM; minor->type = type; minor->dev = dev; r = xa_alloc(drm_minor_get_xa(type), &minor->index, NULL, DRM_MINOR_LIMIT(type), GFP_KERNEL); if (r == -EBUSY && (type == DRM_MINOR_PRIMARY || type == DRM_MINOR_RENDER)) r = xa_alloc(&drm_minors_xa, &minor->index, NULL, DRM_EXTENDED_MINOR_LIMIT, GFP_KERNEL); if (r < 0) return 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, enum drm_minor_type type) { struct drm_minor *minor; void *entry; int ret; DRM_DEBUG("\n"); minor = *drm_minor_get_slot(dev, type); if (!minor) return 0; if (minor->type != DRM_MINOR_ACCEL) { ret = drm_debugfs_register(minor, minor->index); 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 */ entry = xa_store(drm_minor_get_xa(type), minor->index, minor, GFP_KERNEL); if (xa_is_err(entry)) { ret = xa_err(entry); goto err_debugfs; } WARN_ON(entry); DRM_DEBUG("new minor registered %d\n", minor->index); return 0; err_debugfs: drm_debugfs_unregister(minor); return ret; } static void drm_minor_unregister(struct drm_device *dev, enum drm_minor_type type) { struct drm_minor *minor; 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 */ xa_store(drm_minor_get_xa(type), minor->index, NULL, GFP_KERNEL); device_del(minor->kdev); dev_set_drvdata(minor->kdev, NULL); /* safety belt */ drm_debugfs_unregister(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(struct xarray *minor_xa, unsigned int minor_id) { struct drm_minor *minor; xa_lock(minor_xa); minor = xa_load(minor_xa, minor_id); if (minor) drm_dev_get(minor->dev); xa_unlock(minor_xa); 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_{...}_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_dev_set_dma_dev - set the DMA device for a DRM device * @dev: DRM device * @dma_dev: DMA device or NULL * * Sets the DMA device of the given DRM device. Only required if * the DMA device is different from the DRM device's parent. After * calling this function, the DRM device holds a reference on * @dma_dev. Pass NULL to clear the DMA device. */ void drm_dev_set_dma_dev(struct drm_device *dev, struct device *dma_dev) { dma_dev = get_device(dma_dev); put_device(dev->dma_dev); dev->dma_dev = dma_dev; } EXPORT_SYMBOL(drm_dev_set_dma_dev); /* * Available recovery methods for wedged device. To be sent along with device * wedged uevent. */ static const char *drm_get_wedge_recovery(unsigned int opt) { switch (BIT(opt)) { case DRM_WEDGE_RECOVERY_NONE: return "none"; case DRM_WEDGE_RECOVERY_REBIND: return "rebind"; case DRM_WEDGE_RECOVERY_BUS_RESET: return "bus-reset"; case DRM_WEDGE_RECOVERY_VENDOR: return "vendor-specific"; default: return NULL; } } #define WEDGE_STR_LEN 32 #define PID_STR_LEN 15 #define COMM_STR_LEN (TASK_COMM_LEN + 5) /** * drm_dev_wedged_event - generate a device wedged uevent * @dev: DRM device * @method: method(s) to be used for recovery * @info: optional information about the guilty task * * This generates a device wedged uevent for the DRM device specified by @dev. * Recovery @method\(s) of choice will be sent in the uevent environment as * ``WEDGED=<method1>[,..,<methodN>]`` in order of less to more side-effects. * If caller is unsure about recovery or @method is unknown (0), * ``WEDGED=unknown`` will be sent instead. * * Refer to "Device Wedging" chapter in Documentation/gpu/drm-uapi.rst for more * details. * * Returns: 0 on success, negative error code otherwise. */ int drm_dev_wedged_event(struct drm_device *dev, unsigned long method, struct drm_wedge_task_info *info) { char event_string[WEDGE_STR_LEN], pid_string[PID_STR_LEN], comm_string[COMM_STR_LEN]; char *envp[] = { event_string, NULL, NULL, NULL }; const char *recovery = NULL; unsigned int len, opt; len = scnprintf(event_string, sizeof(event_string), "%s", "WEDGED="); for_each_set_bit(opt, &method, BITS_PER_TYPE(method)) { recovery = drm_get_wedge_recovery(opt); if (drm_WARN_ONCE(dev, !recovery, "invalid recovery method %u\n", opt)) break; len += scnprintf(event_string + len, sizeof(event_string) - len, "%s,", recovery); } if (recovery) /* Get rid of trailing comma */ event_string[len - 1] = '\0'; else /* Caller is unsure about recovery, do the best we can at this point. */ snprintf(event_string, sizeof(event_string), "%s", "WEDGED=unknown"); drm_info(dev, "device wedged, %s\n", method == DRM_WEDGE_RECOVERY_NONE ? "but recovered through reset" : "needs recovery"); if (info && (info->comm[0] != '\0') && (info->pid >= 0)) { snprintf(pid_string, sizeof(pid_string), "PID=%u", info->pid); snprintf(comm_string, sizeof(comm_string), "TASK=%s", info->comm); envp[1] = pid_string; envp[2] = comm_string; } return kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp); } EXPORT_SYMBOL(drm_dev_wedged_event); /* * 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_fs_inode_free(dev->anon_inode); put_device(dev->dma_dev); dev->dma_dev = NULL; 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); } 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; if (drm_core_check_feature(dev, DRIVER_COMPUTE_ACCEL) && (drm_core_check_feature(dev, DRIVER_RENDER) || drm_core_check_feature(dev, DRIVER_MODESET))) { DRM_ERROR("DRM driver can't be both a compute acceleration and graphics driver\n"); return -EINVAL; } INIT_LIST_HEAD(&dev->filelist); INIT_LIST_HEAD(&dev->filelist_internal); INIT_LIST_HEAD(&dev->clientlist); INIT_LIST_HEAD(&dev->client_sysrq_list); INIT_LIST_HEAD(&dev->vblank_event_list); spin_lock_init(&dev->event_lock); mutex_init(&dev->filelist_mutex); mutex_init(&dev->clientlist_mutex); mutex_init(&dev->master_mutex); raw_spin_lock_init(&dev->mode_config.panic_lock); 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_COMPUTE_ACCEL)) { ret = drm_minor_alloc(dev, DRM_MINOR_ACCEL); if (ret) goto err; } else { 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; } 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; } } dev->unique = drmm_kstrdup(dev, dev_name(parent), GFP_KERNEL); if (!dev->unique) { ret = -ENOMEM; goto err; } drm_debugfs_dev_init(dev); 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 - Allocation of a &drm_device instance * @parent: Parent device object * @driver: DRM driver * @size: the size of the struct which contains struct drm_device * @offset: the offset of the &drm_device within the container. * * This should *NOT* be by any drivers, but is a dedicated interface for the * corresponding Rust abstraction. * * This is the same as devm_drm_dev_alloc(), but without the corresponding * resource management through the parent device, but not the same as * drm_dev_alloc(), since the latter is the deprecated version, which does not * support subclassing. * * Returns: A pointer to new DRM device, or an ERR_PTR on failure. */ void *__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 = drm_dev_init(drm, driver, parent); if (ret) { kfree(container); return ERR_PTR(ret); } drmm_add_final_kfree(drm, container); return container; } EXPORT_SYMBOL(__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) { return __drm_dev_alloc(parent, driver, sizeof(struct drm_device), 0); } EXPORT_SYMBOL(drm_dev_alloc); static void drm_dev_release(struct kref *ref) { struct drm_device *dev = container_of(ref, struct drm_device, ref); /* Just in case register/unregister was never called */ drm_debugfs_dev_fini(dev); 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 void drmm_cg_unregister_region(struct drm_device *dev, void *arg) { dmem_cgroup_unregister_region(arg); } /** * drmm_cgroup_register_region - Register a region of a DRM device to cgroups * @dev: device for region * @region_name: Region name for registering * @size: Size of region in bytes * * This decreases the ref-count of @dev by one. The device is destroyed if the * ref-count drops to zero. */ struct dmem_cgroup_region *drmm_cgroup_register_region(struct drm_device *dev, const char *region_name, u64 size) { struct dmem_cgroup_region *region; int ret; region = dmem_cgroup_register_region(size, "drm/%s/%s", dev->unique, region_name); if (IS_ERR_OR_NULL(region)) return region; ret = drmm_add_action_or_reset(dev, drmm_cg_unregister_region, region); if (ret) return ERR_PTR(ret); return region; } EXPORT_SYMBOL_GPL(drmm_cgroup_register_region); 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); if (drm_core_check_feature(dev, DRIVER_COMPUTE_ACCEL)) accel_debugfs_register(dev); else drm_debugfs_dev_register(dev); 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 = drm_minor_register(dev, DRM_MINOR_ACCEL); if (ret) goto err_minors; ret = create_compat_control_link(dev); if (ret) goto err_minors; dev->registered = true; if (driver->load) { ret = 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_panic_register(dev); drm_client_sysrq_register(dev); DRM_INFO("Initialized %s %d.%d.%d for %s on minor %d\n", driver->name, driver->major, driver->minor, driver->patchlevel, dev->dev ? dev_name(dev->dev) : "virtual device", dev->primary ? dev->primary->index : dev->accel->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_ACCEL); 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, unless it is managed with devres * (as devices allocated with devm_drm_dev_alloc() are), in which case there is * already an unwind action registered. * * 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) { dev->registered = false; drm_client_sysrq_unregister(dev); drm_panic_unregister(dev); 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); remove_compat_control_link(dev); drm_minor_unregister(dev, DRM_MINOR_ACCEL); drm_minor_unregister(dev, DRM_MINOR_PRIMARY); drm_minor_unregister(dev, DRM_MINOR_RENDER); drm_debugfs_dev_fini(dev); } EXPORT_SYMBOL(drm_dev_unregister); /* * 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(&drm_minors_xa, 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(); drm_panic_exit(); accel_core_exit(); unregister_chrdev(DRM_MAJOR, "drm"); drm_debugfs_remove_root(); drm_sysfs_destroy(); WARN_ON(!xa_empty(&drm_minors_xa)); drm_connector_ida_destroy(); } static int __init drm_core_init(void) { int ret; drm_connector_ida_init(); drm_memcpy_init_early(); ret = drm_sysfs_init(); if (ret < 0) { DRM_ERROR("Cannot create DRM class: %d\n", ret); goto error; } drm_debugfs_init_root(); drm_debugfs_bridge_params(); ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops); if (ret < 0) goto error; ret = accel_core_init(); if (ret < 0) goto error; drm_panic_init(); 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);
