diff options
Diffstat (limited to 'kernel/drivers/gpu/drm/drm_drv.c')
| -rw-r--r-- | kernel/drivers/gpu/drm/drm_drv.c | 912 |
1 files changed, 912 insertions, 0 deletions
diff --git a/kernel/drivers/gpu/drm/drm_drv.c b/kernel/drivers/gpu/drm/drm_drv.c new file mode 100644 index 000000000..48f7359e2 --- /dev/null +++ b/kernel/drivers/gpu/drm/drm_drv.c @@ -0,0 +1,912 @@ +/* + * 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 <drm/drmP.h> +#include <drm/drm_core.h> +#include "drm_legacy.h" +#include "drm_internal.h" + +unsigned int drm_debug = 0; /* 1 to enable debug output */ +EXPORT_SYMBOL(drm_debug); + +bool drm_atomic = 0; + +MODULE_AUTHOR(CORE_AUTHOR); +MODULE_DESCRIPTION(CORE_DESC); +MODULE_LICENSE("GPL and additional rights"); +MODULE_PARM_DESC(debug, "Enable debug output"); +MODULE_PARM_DESC(atomic, "Enable experimental atomic KMS API"); +MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)"); +MODULE_PARM_DESC(timestamp_precision_usec, "Max. error on timestamps [usecs]"); +MODULE_PARM_DESC(timestamp_monotonic, "Use monotonic timestamps"); + +module_param_named(debug, drm_debug, int, 0600); +module_param_named_unsafe(atomic, drm_atomic, bool, 0600); + +static DEFINE_SPINLOCK(drm_minor_lock); +static struct idr drm_minors_idr; + +struct class *drm_class; +static struct dentry *drm_debugfs_root; + +void drm_err(const char *format, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, format); + + vaf.fmt = format; + vaf.va = &args; + + printk(KERN_ERR "[" DRM_NAME ":%ps] *ERROR* %pV", + __builtin_return_address(0), &vaf); + + va_end(args); +} +EXPORT_SYMBOL(drm_err); + +void drm_ut_debug_printk(const char *function_name, const char *format, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, format); + vaf.fmt = format; + vaf.va = &args; + + printk(KERN_DEBUG "[" DRM_NAME ":%s] %pV", function_name, &vaf); + + va_end(args); +} +EXPORT_SYMBOL(drm_ut_debug_printk); + +#define DRM_MAGIC_HASH_ORDER 4 /**< Size of key hash table. Must be power of 2. */ + +struct drm_master *drm_master_create(struct drm_minor *minor) +{ + struct drm_master *master; + + master = kzalloc(sizeof(*master), GFP_KERNEL); + if (!master) + return NULL; + + kref_init(&master->refcount); + spin_lock_init(&master->lock.spinlock); + init_waitqueue_head(&master->lock.lock_queue); + if (drm_ht_create(&master->magiclist, DRM_MAGIC_HASH_ORDER)) { + kfree(master); + return NULL; + } + INIT_LIST_HEAD(&master->magicfree); + master->minor = minor; + + return master; +} + +struct drm_master *drm_master_get(struct drm_master *master) +{ + kref_get(&master->refcount); + return master; +} +EXPORT_SYMBOL(drm_master_get); + +static void drm_master_destroy(struct kref *kref) +{ + struct drm_master *master = container_of(kref, struct drm_master, refcount); + struct drm_device *dev = master->minor->dev; + struct drm_map_list *r_list, *list_temp; + + mutex_lock(&dev->struct_mutex); + if (dev->driver->master_destroy) + dev->driver->master_destroy(dev, master); + + list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) { + if (r_list->master == master) { + drm_legacy_rmmap_locked(dev, r_list->map); + r_list = NULL; + } + } + + if (master->unique) { + kfree(master->unique); + master->unique = NULL; + master->unique_len = 0; + } + + drm_ht_remove(&master->magiclist); + + mutex_unlock(&dev->struct_mutex); + kfree(master); +} + +void drm_master_put(struct drm_master **master) +{ + kref_put(&(*master)->refcount, drm_master_destroy); + *master = NULL; +} +EXPORT_SYMBOL(drm_master_put); + +int drm_setmaster_ioctl(struct drm_device *dev, void *data, + struct drm_file *file_priv) +{ + int ret = 0; + + mutex_lock(&dev->master_mutex); + if (file_priv->is_master) + goto out_unlock; + + if (file_priv->minor->master) { + ret = -EINVAL; + goto out_unlock; + } + + if (!file_priv->master) { + ret = -EINVAL; + goto out_unlock; + } + + file_priv->minor->master = drm_master_get(file_priv->master); + file_priv->is_master = 1; + if (dev->driver->master_set) { + ret = dev->driver->master_set(dev, file_priv, false); + if (unlikely(ret != 0)) { + file_priv->is_master = 0; + drm_master_put(&file_priv->minor->master); + } + } + +out_unlock: + mutex_unlock(&dev->master_mutex); + return ret; +} + +int drm_dropmaster_ioctl(struct drm_device *dev, void *data, + struct drm_file *file_priv) +{ + int ret = -EINVAL; + + mutex_lock(&dev->master_mutex); + if (!file_priv->is_master) + goto out_unlock; + + if (!file_priv->minor->master) + goto out_unlock; + + ret = 0; + if (dev->driver->master_drop) + dev->driver->master_drop(dev, file_priv, false); + drm_master_put(&file_priv->minor->master); + file_priv->is_master = 0; + +out_unlock: + mutex_unlock(&dev->master_mutex); + return ret; +} + +/* + * 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_LEGACY: + return &dev->primary; + case DRM_MINOR_RENDER: + return &dev->render; + case DRM_MINOR_CONTROL: + return &dev->control; + default: + return NULL; + } +} + +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; + + drm_mode_group_destroy(&minor->mode_group); + 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"); + return ret; + } + + 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); +} + +/** + * drm_minor_acquire - Acquire a DRM minor + * @minor_id: Minor ID of the DRM-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. + * + * Returns: + * Pointer to minor-object with increased device-refcount, or PTR_ERR on + * failure. + */ +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_ref(minor->dev); + spin_unlock_irqrestore(&drm_minor_lock, flags); + + if (!minor) { + return ERR_PTR(-ENODEV); + } else if (drm_device_is_unplugged(minor->dev)) { + drm_dev_unref(minor->dev); + return ERR_PTR(-ENODEV); + } + + return minor; +} + +/** + * drm_minor_release - Release DRM minor + * @minor: Pointer to DRM minor object + * + * Release a minor that was previously acquired via drm_minor_acquire(). + */ +void drm_minor_release(struct drm_minor *minor) +{ + drm_dev_unref(minor->dev); +} + +/** + * drm_put_dev - Unregister and release a DRM device + * @dev: DRM device + * + * Called at module unload time or when a PCI device is unplugged. + * + * Use of this function is discouraged. It will eventually go away completely. + * Please use drm_dev_unregister() and drm_dev_unref() explicitly instead. + * + * Cleans up all DRM device, calling drm_lastclose(). + */ +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_unref(dev); +} +EXPORT_SYMBOL(drm_put_dev); + +void drm_unplug_dev(struct drm_device *dev) +{ + /* for a USB device */ + drm_minor_unregister(dev, DRM_MINOR_LEGACY); + drm_minor_unregister(dev, DRM_MINOR_RENDER); + drm_minor_unregister(dev, DRM_MINOR_CONTROL); + + mutex_lock(&drm_global_mutex); + + drm_device_set_unplugged(dev); + + if (dev->open_count == 0) { + drm_put_dev(dev); + } + mutex_unlock(&drm_global_mutex); +} +EXPORT_SYMBOL(drm_unplug_dev); + +/* + * 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_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. + * + * The initial ref-count of the object is 1. Use drm_dev_ref() and + * drm_dev_unref() to take and drop further ref-counts. + * + * Note that for purely virtual devices @parent can be NULL. + * + * RETURNS: + * Pointer to new DRM device, or NULL if out of memory. + */ +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 NULL; + + kref_init(&dev->ref); + dev->dev = parent; + dev->driver = driver; + + INIT_LIST_HEAD(&dev->filelist); + 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->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_MODESET)) { + ret = drm_minor_alloc(dev, DRM_MINOR_CONTROL); + if (ret) + goto err_minors; + } + + 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_LEGACY); + if (ret) + goto err_minors; + + if (drm_ht_create(&dev->map_hash, 12)) + goto err_minors; + + ret = drm_legacy_ctxbitmap_init(dev); + if (ret) { + DRM_ERROR("Cannot allocate memory for context bitmap.\n"); + goto err_ht; + } + + 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; + } + } + + return dev; + +err_ctxbitmap: + drm_legacy_ctxbitmap_cleanup(dev); +err_ht: + drm_ht_remove(&dev->map_hash); +err_minors: + drm_minor_free(dev, DRM_MINOR_LEGACY); + drm_minor_free(dev, DRM_MINOR_RENDER); + drm_minor_free(dev, DRM_MINOR_CONTROL); + drm_fs_inode_free(dev->anon_inode); +err_free: + mutex_destroy(&dev->master_mutex); + kfree(dev); + return NULL; +} +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 (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_LEGACY); + drm_minor_free(dev, DRM_MINOR_RENDER); + drm_minor_free(dev, DRM_MINOR_CONTROL); + + mutex_destroy(&dev->master_mutex); + kfree(dev->unique); + kfree(dev); +} + +/** + * drm_dev_ref - 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_unref() 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_ref(struct drm_device *dev) +{ + if (dev) + kref_get(&dev->ref); +} +EXPORT_SYMBOL(drm_dev_ref); + +/** + * drm_dev_unref - 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_unref(struct drm_device *dev) +{ + if (dev) + kref_put(&dev->ref, drm_dev_release); +} +EXPORT_SYMBOL(drm_dev_unref); + +/** + * 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! + * + * RETURNS: + * 0 on success, negative error code on failure. + */ +int drm_dev_register(struct drm_device *dev, unsigned long flags) +{ + int ret; + + mutex_lock(&drm_global_mutex); + + ret = drm_minor_register(dev, DRM_MINOR_CONTROL); + if (ret) + goto err_minors; + + ret = drm_minor_register(dev, DRM_MINOR_RENDER); + if (ret) + goto err_minors; + + ret = drm_minor_register(dev, DRM_MINOR_LEGACY); + if (ret) + goto err_minors; + + if (dev->driver->load) { + ret = dev->driver->load(dev, flags); + if (ret) + goto err_minors; + } + + /* setup grouping for legacy outputs */ + if (drm_core_check_feature(dev, DRIVER_MODESET)) { + ret = drm_mode_group_init_legacy_group(dev, + &dev->primary->mode_group); + if (ret) + goto err_unload; + } + + ret = 0; + goto out_unlock; + +err_unload: + if (dev->driver->unload) + dev->driver->unload(dev); +err_minors: + drm_minor_unregister(dev, DRM_MINOR_LEGACY); + drm_minor_unregister(dev, DRM_MINOR_RENDER); + drm_minor_unregister(dev, DRM_MINOR_CONTROL); +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_unref() to drop their final reference. + */ +void drm_dev_unregister(struct drm_device *dev) +{ + struct drm_map_list *r_list, *list_temp; + + drm_lastclose(dev); + + if (dev->driver->unload) + dev->driver->unload(dev); + + if (dev->agp) + drm_pci_agp_destroy(dev); + + drm_vblank_cleanup(dev); + + list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) + drm_legacy_rmmap(dev, r_list->map); + + drm_minor_unregister(dev, DRM_MINOR_LEGACY); + drm_minor_unregister(dev, DRM_MINOR_RENDER); + drm_minor_unregister(dev, DRM_MINOR_CONTROL); +} +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 + * @fmt: format string for unique name + * + * Sets the unique name of a DRM device using the specified format string and + * a variable list of arguments. 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 *fmt, ...) +{ + va_list ap; + + kfree(dev->unique); + + va_start(ap, fmt); + dev->unique = kvasprintf(GFP_KERNEL, fmt, ap); + va_end(ap); + + 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 int __init drm_core_init(void) +{ + int ret = -ENOMEM; + + drm_global_init(); + drm_connector_ida_init(); + idr_init(&drm_minors_idr); + + if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops)) + goto err_p1; + + drm_class = drm_sysfs_create(THIS_MODULE, "drm"); + if (IS_ERR(drm_class)) { + printk(KERN_ERR "DRM: Error creating drm class.\n"); + ret = PTR_ERR(drm_class); + goto err_p2; + } + + drm_debugfs_root = debugfs_create_dir("dri", NULL); + if (!drm_debugfs_root) { + DRM_ERROR("Cannot create /sys/kernel/debug/dri\n"); + ret = -1; + goto err_p3; + } + + DRM_INFO("Initialized %s %d.%d.%d %s\n", + CORE_NAME, CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE); + return 0; +err_p3: + drm_sysfs_destroy(); +err_p2: + unregister_chrdev(DRM_MAJOR, "drm"); + + idr_destroy(&drm_minors_idr); +err_p1: + return ret; +} + +static void __exit drm_core_exit(void) +{ + debugfs_remove(drm_debugfs_root); + drm_sysfs_destroy(); + + unregister_chrdev(DRM_MAJOR, "drm"); + + drm_connector_ida_destroy(); + idr_destroy(&drm_minors_idr); +} + +module_init(drm_core_init); +module_exit(drm_core_exit); |