--- zzzz-none-000/linux-3.10.107/drivers/gpu/drm/drm_auth.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/drivers/gpu/drm/drm_auth.c 2021-02-04 17:41:59.000000000 +0000 @@ -1,11 +1,3 @@ -/** - * \file drm_auth.c - * IOCTLs for authentication - * - * \author Rickard E. (Rik) Faith - * \author Gareth Hughes - */ - /* * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com * @@ -13,6 +5,9 @@ * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. * All Rights Reserved. * + * Author Rickard E. (Rik) Faith + * Author Gareth Hughes + * * 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 @@ -34,149 +29,49 @@ */ #include +#include "drm_internal.h" /** - * Find the file with the given magic number. + * drm_getmagic - Get unique magic of a client + * @dev: DRM device to operate on + * @data: ioctl data containing the drm_auth object + * @file_priv: DRM file that performs the operation * - * \param dev DRM device. - * \param magic magic number. + * This looks up the unique magic of the passed client and returns it. If the + * client did not have a magic assigned, yet, a new one is registered. The magic + * is stored in the passed drm_auth object. * - * Searches in drm_device::magiclist within all files with the same hash key - * the one with matching magic number, while holding the drm_device::struct_mutex - * lock. - */ -static struct drm_file *drm_find_file(struct drm_master *master, drm_magic_t magic) -{ - struct drm_file *retval = NULL; - struct drm_magic_entry *pt; - struct drm_hash_item *hash; - struct drm_device *dev = master->minor->dev; - - mutex_lock(&dev->struct_mutex); - if (!drm_ht_find_item(&master->magiclist, (unsigned long)magic, &hash)) { - pt = drm_hash_entry(hash, struct drm_magic_entry, hash_item); - retval = pt->priv; - } - mutex_unlock(&dev->struct_mutex); - return retval; -} - -/** - * Adds a magic number. - * - * \param dev DRM device. - * \param priv file private data. - * \param magic magic number. - * - * Creates a drm_magic_entry structure and appends to the linked list - * associated the magic number hash key in drm_device::magiclist, while holding - * the drm_device::struct_mutex lock. - */ -static int drm_add_magic(struct drm_master *master, struct drm_file *priv, - drm_magic_t magic) -{ - struct drm_magic_entry *entry; - struct drm_device *dev = master->minor->dev; - DRM_DEBUG("%d\n", magic); - - entry = kzalloc(sizeof(*entry), GFP_KERNEL); - if (!entry) - return -ENOMEM; - entry->priv = priv; - entry->hash_item.key = (unsigned long)magic; - mutex_lock(&dev->struct_mutex); - drm_ht_insert_item(&master->magiclist, &entry->hash_item); - list_add_tail(&entry->head, &master->magicfree); - mutex_unlock(&dev->struct_mutex); - - return 0; -} - -/** - * Remove a magic number. - * - * \param dev DRM device. - * \param magic magic number. - * - * Searches and unlinks the entry in drm_device::magiclist with the magic - * number hash key, while holding the drm_device::struct_mutex lock. - */ -int drm_remove_magic(struct drm_master *master, drm_magic_t magic) -{ - struct drm_magic_entry *pt; - struct drm_hash_item *hash; - struct drm_device *dev = master->minor->dev; - - DRM_DEBUG("%d\n", magic); - - mutex_lock(&dev->struct_mutex); - if (drm_ht_find_item(&master->magiclist, (unsigned long)magic, &hash)) { - mutex_unlock(&dev->struct_mutex); - return -EINVAL; - } - pt = drm_hash_entry(hash, struct drm_magic_entry, hash_item); - drm_ht_remove_item(&master->magiclist, hash); - list_del(&pt->head); - mutex_unlock(&dev->struct_mutex); - - kfree(pt); - - return 0; -} - -/** - * Get a unique magic number (ioctl). - * - * \param inode device inode. - * \param file_priv DRM file private. - * \param cmd command. - * \param arg pointer to a resulting drm_auth structure. - * \return zero on success, or a negative number on failure. - * - * If there is a magic number in drm_file::magic then use it, otherwise - * searches an unique non-zero magic number and add it associating it with \p - * file_priv. - * This ioctl needs protection by the drm_global_mutex, which protects - * struct drm_file::magic and struct drm_magic_entry::priv. + * Returns: 0 on success, negative error code on failure. */ int drm_getmagic(struct drm_device *dev, void *data, struct drm_file *file_priv) { - static drm_magic_t sequence = 0; - static DEFINE_SPINLOCK(lock); struct drm_auth *auth = data; + int ret = 0; - /* Find unique magic */ - if (file_priv->magic) { - auth->magic = file_priv->magic; - } else { - do { - spin_lock(&lock); - if (!sequence) - ++sequence; /* reserve 0 */ - auth->magic = sequence++; - spin_unlock(&lock); - } while (drm_find_file(file_priv->master, auth->magic)); - file_priv->magic = auth->magic; - drm_add_magic(file_priv->master, file_priv, auth->magic); + mutex_lock(&dev->struct_mutex); + if (!file_priv->magic) { + ret = idr_alloc(&file_priv->master->magic_map, file_priv, + 1, 0, GFP_KERNEL); + if (ret >= 0) + file_priv->magic = ret; } + auth->magic = file_priv->magic; + mutex_unlock(&dev->struct_mutex); DRM_DEBUG("%u\n", auth->magic); - return 0; + return ret < 0 ? ret : 0; } /** - * Authenticate with a magic. + * drm_authmagic - Authenticate client with a magic + * @dev: DRM device to operate on + * @data: ioctl data containing the drm_auth object + * @file_priv: DRM file that performs the operation * - * \param inode device inode. - * \param file_priv DRM file private. - * \param cmd command. - * \param arg pointer to a drm_auth structure. - * \return zero if authentication successed, or a negative number otherwise. - * - * Checks if \p file_priv is associated with the magic number passed in \arg. - * This ioctl needs protection by the drm_global_mutex, which protects - * struct drm_file::magic and struct drm_magic_entry::priv. + * This looks up a DRM client by the passed magic and authenticates it. + * + * Returns: 0 on success, negative error code on failure. */ int drm_authmagic(struct drm_device *dev, void *data, struct drm_file *file_priv) @@ -185,10 +80,14 @@ struct drm_file *file; DRM_DEBUG("%u\n", auth->magic); - if ((file = drm_find_file(file_priv->master, auth->magic))) { + + mutex_lock(&dev->struct_mutex); + file = idr_find(&file_priv->master->magic_map, auth->magic); + if (file) { file->authenticated = 1; - drm_remove_magic(file_priv->master, auth->magic); - return 0; + idr_replace(&file_priv->master->magic_map, NULL, auth->magic); } - return -EINVAL; + mutex_unlock(&dev->struct_mutex); + + return file ? 0 : -EINVAL; }