--- /dev/null
+/**
+ * \file drm_auth.c
+ * IOCTLs for authentication
+ *
+ * \author Rickard E. (Rik) Faith <faith@valinux.com>
+ * \author Gareth Hughes <gareth@valinux.com>
+ */
+
+/*
+ * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com
+ *
+ * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
+ * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
+ * All Rights Reserved.
+ *
+ * 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
+ * VA LINUX SYSTEMS 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 <drm/drmP.h>
+#include "drm_internal.h"
+
+struct drm_magic_entry {
+ struct list_head head;
+ struct drm_hash_item hash_item;
+ struct drm_file *priv;
+};
+
+/**
+ * Find the file with the given magic number.
+ *
+ * \param dev DRM device.
+ * \param magic magic number.
+ *
+ * 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.
+ */
+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;
+
+ /* 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);
+ }
+
+ DRM_DEBUG("%u\n", auth->magic);
+
+ return 0;
+}
+
+/**
+ * Authenticate with a magic.
+ *
+ * \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.
+ */
+int drm_authmagic(struct drm_device *dev, void *data,
+ struct drm_file *file_priv)
+{
+ struct drm_auth *auth = data;
+ struct drm_file *file;
+
+ DRM_DEBUG("%u\n", auth->magic);
+ if ((file = drm_find_file(file_priv->master, auth->magic))) {
+ file->authenticated = 1;
+ drm_remove_magic(file_priv->master, auth->magic);
+ return 0;
+ }
+ return -EINVAL;
+}
Code Review / kvmfornfv.git / blobdiff