drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf_res.c - kernel/lockdown - Git at Google

 /**************************************************************************
  *
  * Copyright © 2014 VMware, Inc., Palo Alto, CA., USA
  * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
  * THE COPYRIGHT HOLDERS, AUTHORS 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 "vmwgfx_drv.h"

 #define VMW_CMDBUF_RES_MAN_HT_ORDER 12

 enum vmw_cmdbuf_res_state {
 	VMW_CMDBUF_RES_COMMITED,
 	VMW_CMDBUF_RES_ADD,
 	VMW_CMDBUF_RES_DEL
 };

 /**
  * struct vmw_cmdbuf_res - Command buffer managed resource entry.
  *
  * @res: Refcounted pointer to a struct vmw_resource.
  * @hash: Hash entry for the manager hash table.
  * @head: List head used either by the staging list or the manager list
  * of commited resources.
  * @state: Staging state of this resource entry.
  * @man: Pointer to a resource manager for this entry.
  */
 struct vmw_cmdbuf_res {
 	struct vmw_resource *res;
 	struct drm_hash_item hash;
 	struct list_head head;
 	enum vmw_cmdbuf_res_state state;
 	struct vmw_cmdbuf_res_manager *man;
 };

 /**
  * struct vmw_cmdbuf_res_manager - Command buffer resource manager.
  *
  * @resources: Hash table containing staged and commited command buffer
  * resources
  * @list: List of commited command buffer resources.
  * @dev_priv: Pointer to a device private structure.
  *
  * @resources and @list are protected by the cmdbuf mutex for now.
  */
 struct vmw_cmdbuf_res_manager {
 	struct drm_open_hash resources;
 	struct list_head list;
 	struct vmw_private *dev_priv;
 };


 /**
  * vmw_cmdbuf_res_lookup - Look up a command buffer resource
  *
  * @man: Pointer to the command buffer resource manager
  * @resource_type: The resource type, that combined with the user key
  * identifies the resource.
  * @user_key: The user key.
  *
  * Returns a valid refcounted struct vmw_resource pointer on success,
  * an error pointer on failure.
  */
 struct vmw_resource *
 vmw_cmdbuf_res_lookup(struct vmw_cmdbuf_res_manager *man,
 		      enum vmw_cmdbuf_res_type res_type,
 		      u32 user_key)
 {
 	struct drm_hash_item *hash;
 	int ret;
 	unsigned long key = user_key | (res_type << 24);

 	ret = drm_ht_find_item(&man->resources, key, &hash);
 	if (unlikely(ret != 0))
 		return ERR_PTR(ret);

 	return vmw_resource_reference
 		(drm_hash_entry(hash, struct vmw_cmdbuf_res, hash)->res);
 }

 /**
  * vmw_cmdbuf_res_free - Free a command buffer resource.
  *
  * @man: Pointer to the command buffer resource manager
  * @entry: Pointer to a struct vmw_cmdbuf_res.
  *
  * Frees a struct vmw_cmdbuf_res entry and drops its reference to the
  * struct vmw_resource.
  */
 static void vmw_cmdbuf_res_free(struct vmw_cmdbuf_res_manager *man,
 				struct vmw_cmdbuf_res *entry)
 {
 	list_del(&entry->head);
 	WARN_ON(drm_ht_remove_item(&man->resources, &entry->hash));
 	vmw_resource_unreference(&entry->res);
 	kfree(entry);
 }

 /**
  * vmw_cmdbuf_res_commit - Commit a list of command buffer resource actions
  *
  * @list: Caller's list of command buffer resource actions.
  *
  * This function commits a list of command buffer resource
  * additions or removals.
  * It is typically called when the execbuf ioctl call triggering these
  * actions has commited the fifo contents to the device.
  */
 void vmw_cmdbuf_res_commit(struct list_head *list)
 {
 	struct vmw_cmdbuf_res *entry, *next;

 	list_for_each_entry_safe(entry, next, list, head) {
 		list_del(&entry->head);
 		switch (entry->state) {
 		case VMW_CMDBUF_RES_ADD:
 			entry->state = VMW_CMDBUF_RES_COMMITED;
 			list_add_tail(&entry->head, &entry->man->list);
 			break;
 		case VMW_CMDBUF_RES_DEL:
 			vmw_resource_unreference(&entry->res);
 			kfree(entry);
 			break;
 		default:
 			BUG();
 			break;
 		}
 	}
 }

 /**
  * vmw_cmdbuf_res_revert - Revert a list of command buffer resource actions
  *
  * @man: Pointer to the command buffer resource manager
  * @list: Caller's list of command buffer resource action
  *
  * This function reverts a list of command buffer resource
  * additions or removals.
  * It is typically called when the execbuf ioctl call triggering these
  * actions failed for some reason, and the command stream was never
  * submitted.
  */
 void vmw_cmdbuf_res_revert(struct list_head *list)
 {
 	struct vmw_cmdbuf_res *entry, *next;
 	int ret;

 	list_for_each_entry_safe(entry, next, list, head) {
 		switch (entry->state) {
 		case VMW_CMDBUF_RES_ADD:
 			vmw_cmdbuf_res_free(entry->man, entry);
 			break;
 		case VMW_CMDBUF_RES_DEL:
 			ret = drm_ht_insert_item(&entry->man->resources,
 						 &entry->hash);
 			list_del(&entry->head);
 			list_add_tail(&entry->head, &entry->man->list);
 			entry->state = VMW_CMDBUF_RES_COMMITED;
 			break;
 		default:
 			BUG();
 			break;
 		}
 	}
 }

 /**
  * vmw_cmdbuf_res_add - Stage a command buffer managed resource for addition.
  *
  * @man: Pointer to the command buffer resource manager.
  * @res_type: The resource type.
  * @user_key: The user-space id of the resource.
  * @res: Valid (refcount != 0) pointer to a struct vmw_resource.
  * @list: The staging list.
  *
  * This function allocates a struct vmw_cmdbuf_res entry and adds the
  * resource to the hash table of the manager identified by @man. The
  * entry is then put on the staging list identified by @list.
  */
 int vmw_cmdbuf_res_add(struct vmw_cmdbuf_res_manager *man,
 		       enum vmw_cmdbuf_res_type res_type,
 		       u32 user_key,
 		       struct vmw_resource *res,
 		       struct list_head *list)
 {
 	struct vmw_cmdbuf_res *cres;
 	int ret;

 	cres = kzalloc(sizeof(*cres), GFP_KERNEL);
 	if (unlikely(cres == NULL))
 		return -ENOMEM;

 	cres->hash.key = user_key | (res_type << 24);
 	ret = drm_ht_insert_item(&man->resources, &cres->hash);
 	if (unlikely(ret != 0))
 		goto out_invalid_key;

 	cres->state = VMW_CMDBUF_RES_ADD;
 	cres->res = vmw_resource_reference(res);
 	cres->man = man;
 	list_add_tail(&cres->head, list);

 out_invalid_key:
 	return ret;
 }

 /**
  * vmw_cmdbuf_res_remove - Stage a command buffer managed resource for removal.
  *
  * @man: Pointer to the command buffer resource manager.
  * @res_type: The resource type.
  * @user_key: The user-space id of the resource.
  * @list: The staging list.
  *
  * This function looks up the struct vmw_cmdbuf_res entry from the manager
  * hash table and, if it exists, removes it. Depending on its current staging
  * state it then either removes the entry from the staging list or adds it
  * to it with a staging state of removal.
  */
 int vmw_cmdbuf_res_remove(struct vmw_cmdbuf_res_manager *man,
 			  enum vmw_cmdbuf_res_type res_type,
 			  u32 user_key,
 			  struct list_head *list)
 {
 	struct vmw_cmdbuf_res *entry;
 	struct drm_hash_item *hash;
 	int ret;

 	ret = drm_ht_find_item(&man->resources, user_key | (res_type << 24),
 			       &hash);
 	if (likely(ret != 0))
 		return -EINVAL;

 	entry = drm_hash_entry(hash, struct vmw_cmdbuf_res, hash);

 	switch (entry->state) {
 	case VMW_CMDBUF_RES_ADD:
 		vmw_cmdbuf_res_free(man, entry);
 		break;
 	case VMW_CMDBUF_RES_COMMITED:
 		(void) drm_ht_remove_item(&man->resources, &entry->hash);
 		list_del(&entry->head);
 		entry->state = VMW_CMDBUF_RES_DEL;
 		list_add_tail(&entry->head, list);
 		break;
 	default:
 		BUG();
 		break;
 	}

 	return 0;
 }

 /**
  * vmw_cmdbuf_res_man_create - Allocate a command buffer managed resource
  * manager.
  *
  * @dev_priv: Pointer to a struct vmw_private
  *
  * Allocates and initializes a command buffer managed resource manager. Returns
  * an error pointer on failure.
  */
 struct vmw_cmdbuf_res_manager *
 vmw_cmdbuf_res_man_create(struct vmw_private *dev_priv)
 {
 	struct vmw_cmdbuf_res_manager *man;
 	int ret;

 	man = kzalloc(sizeof(*man), GFP_KERNEL);
 	if (man == NULL)
 		return ERR_PTR(-ENOMEM);

 	man->dev_priv = dev_priv;
 	INIT_LIST_HEAD(&man->list);
 	ret = drm_ht_create(&man->resources, VMW_CMDBUF_RES_MAN_HT_ORDER);
 	if (ret == 0)
 		return man;

 	kfree(man);
 	return ERR_PTR(ret);
 }

 /**
  * vmw_cmdbuf_res_man_destroy - Destroy a command buffer managed resource
  * manager.
  *
  * @man: Pointer to the  manager to destroy.
  *
  * This function destroys a command buffer managed resource manager and
  * unreferences / frees all command buffer managed resources and -entries
  * associated with it.
  */
 void vmw_cmdbuf_res_man_destroy(struct vmw_cmdbuf_res_manager *man)
 {
 	struct vmw_cmdbuf_res *entry, *next;

 	list_for_each_entry_safe(entry, next, &man->list, head)
 		vmw_cmdbuf_res_free(man, entry);

 	kfree(man);
 }

 /**
  *
  * vmw_cmdbuf_res_man_size - Return the size of a command buffer managed
  * resource manager
  *
  * Returns the approximate allocation size of a command buffer managed
  * resource manager.
  */
 size_t vmw_cmdbuf_res_man_size(void)
 {
 	static size_t res_man_size;

 	if (unlikely(res_man_size == 0))
 		res_man_size =
 			ttm_round_pot(sizeof(struct vmw_cmdbuf_res_manager)) +
 			ttm_round_pot(sizeof(struct hlist_head) <<
 				      VMW_CMDBUF_RES_MAN_HT_ORDER);

 	return res_man_size;
 }
	/**************************************************************************
	*
	* Copyright © 2014 VMware, Inc., Palo Alto, CA., USA
	* 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDERS, AUTHORS 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 "vmwgfx_drv.h"

	#define VMW_CMDBUF_RES_MAN_HT_ORDER 12

	enum vmw_cmdbuf_res_state {
	VMW_CMDBUF_RES_COMMITED,
	VMW_CMDBUF_RES_ADD,
	VMW_CMDBUF_RES_DEL
	};

	/**
	* struct vmw_cmdbuf_res - Command buffer managed resource entry.
	*
	* @res: Refcounted pointer to a struct vmw_resource.
	* @hash: Hash entry for the manager hash table.
	* @head: List head used either by the staging list or the manager list
	* of commited resources.
	* @state: Staging state of this resource entry.
	* @man: Pointer to a resource manager for this entry.
	*/
	struct vmw_cmdbuf_res {
	struct vmw_resource *res;
	struct drm_hash_item hash;
	struct list_head head;
	enum vmw_cmdbuf_res_state state;
	struct vmw_cmdbuf_res_manager *man;
	};

	/**
	* struct vmw_cmdbuf_res_manager - Command buffer resource manager.
	*
	* @resources: Hash table containing staged and commited command buffer
	* resources
	* @list: List of commited command buffer resources.
	* @dev_priv: Pointer to a device private structure.
	*
	* @resources and @list are protected by the cmdbuf mutex for now.
	*/
	struct vmw_cmdbuf_res_manager {
	struct drm_open_hash resources;
	struct list_head list;
	struct vmw_private *dev_priv;
	};


	/**
	* vmw_cmdbuf_res_lookup - Look up a command buffer resource
	*
	* @man: Pointer to the command buffer resource manager
	* @resource_type: The resource type, that combined with the user key
	* identifies the resource.
	* @user_key: The user key.
	*
	* Returns a valid refcounted struct vmw_resource pointer on success,
	* an error pointer on failure.
	*/
	struct vmw_resource *
	vmw_cmdbuf_res_lookup(struct vmw_cmdbuf_res_manager *man,
	enum vmw_cmdbuf_res_type res_type,
	u32 user_key)
	{
	struct drm_hash_item *hash;
	int ret;
	unsigned long key = user_key \| (res_type << 24);

	ret = drm_ht_find_item(&man->resources, key, &hash);
	if (unlikely(ret != 0))
	return ERR_PTR(ret);

	return vmw_resource_reference
	(drm_hash_entry(hash, struct vmw_cmdbuf_res, hash)->res);
	}

	/**
	* vmw_cmdbuf_res_free - Free a command buffer resource.
	*
	* @man: Pointer to the command buffer resource manager
	* @entry: Pointer to a struct vmw_cmdbuf_res.
	*
	* Frees a struct vmw_cmdbuf_res entry and drops its reference to the
	* struct vmw_resource.
	*/
	static void vmw_cmdbuf_res_free(struct vmw_cmdbuf_res_manager *man,
	struct vmw_cmdbuf_res *entry)
	{
	list_del(&entry->head);
	WARN_ON(drm_ht_remove_item(&man->resources, &entry->hash));
	vmw_resource_unreference(&entry->res);
	kfree(entry);
	}

	/**
	* vmw_cmdbuf_res_commit - Commit a list of command buffer resource actions
	*
	* @list: Caller's list of command buffer resource actions.
	*
	* This function commits a list of command buffer resource
	* additions or removals.
	* It is typically called when the execbuf ioctl call triggering these
	* actions has commited the fifo contents to the device.
	*/
	void vmw_cmdbuf_res_commit(struct list_head *list)
	{
	struct vmw_cmdbuf_res entry, next;

	list_for_each_entry_safe(entry, next, list, head) {
	list_del(&entry->head);
	switch (entry->state) {
	case VMW_CMDBUF_RES_ADD:
	entry->state = VMW_CMDBUF_RES_COMMITED;
	list_add_tail(&entry->head, &entry->man->list);
	break;
	case VMW_CMDBUF_RES_DEL:
	vmw_resource_unreference(&entry->res);
	kfree(entry);
	break;
	default:
	BUG();
	break;
	}
	}
	}

	/**
	* vmw_cmdbuf_res_revert - Revert a list of command buffer resource actions
	*
	* @man: Pointer to the command buffer resource manager
	* @list: Caller's list of command buffer resource action
	*
	* This function reverts a list of command buffer resource
	* additions or removals.
	* It is typically called when the execbuf ioctl call triggering these
	* actions failed for some reason, and the command stream was never
	* submitted.
	*/
	void vmw_cmdbuf_res_revert(struct list_head *list)
	{
	struct vmw_cmdbuf_res entry, next;
	int ret;

	list_for_each_entry_safe(entry, next, list, head) {
	switch (entry->state) {
	case VMW_CMDBUF_RES_ADD:
	vmw_cmdbuf_res_free(entry->man, entry);
	break;
	case VMW_CMDBUF_RES_DEL:
	ret = drm_ht_insert_item(&entry->man->resources,
	&entry->hash);
	list_del(&entry->head);
	list_add_tail(&entry->head, &entry->man->list);
	entry->state = VMW_CMDBUF_RES_COMMITED;
	break;
	default:
	BUG();
	break;
	}
	}
	}

	/**
	* vmw_cmdbuf_res_add - Stage a command buffer managed resource for addition.
	*
	* @man: Pointer to the command buffer resource manager.
	* @res_type: The resource type.
	* @user_key: The user-space id of the resource.
	* @res: Valid (refcount != 0) pointer to a struct vmw_resource.
	* @list: The staging list.
	*
	* This function allocates a struct vmw_cmdbuf_res entry and adds the
	* resource to the hash table of the manager identified by @man. The
	* entry is then put on the staging list identified by @list.
	*/
	int vmw_cmdbuf_res_add(struct vmw_cmdbuf_res_manager *man,
	enum vmw_cmdbuf_res_type res_type,
	u32 user_key,
	struct vmw_resource *res,
	struct list_head *list)
	{
	struct vmw_cmdbuf_res *cres;
	int ret;

	cres = kzalloc(sizeof(*cres), GFP_KERNEL);
	if (unlikely(cres == NULL))
	return -ENOMEM;

	cres->hash.key = user_key \| (res_type << 24);
	ret = drm_ht_insert_item(&man->resources, &cres->hash);
	if (unlikely(ret != 0))
	goto out_invalid_key;

	cres->state = VMW_CMDBUF_RES_ADD;
	cres->res = vmw_resource_reference(res);
	cres->man = man;
	list_add_tail(&cres->head, list);

	out_invalid_key:
	return ret;
	}

	/**
	* vmw_cmdbuf_res_remove - Stage a command buffer managed resource for removal.
	*
	* @man: Pointer to the command buffer resource manager.
	* @res_type: The resource type.
	* @user_key: The user-space id of the resource.
	* @list: The staging list.
	*
	* This function looks up the struct vmw_cmdbuf_res entry from the manager
	* hash table and, if it exists, removes it. Depending on its current staging
	* state it then either removes the entry from the staging list or adds it
	* to it with a staging state of removal.
	*/
	int vmw_cmdbuf_res_remove(struct vmw_cmdbuf_res_manager *man,
	enum vmw_cmdbuf_res_type res_type,
	u32 user_key,
	struct list_head *list)
	{
	struct vmw_cmdbuf_res *entry;
	struct drm_hash_item *hash;
	int ret;

	ret = drm_ht_find_item(&man->resources, user_key \| (res_type << 24),
	&hash);
	if (likely(ret != 0))
	return -EINVAL;

	entry = drm_hash_entry(hash, struct vmw_cmdbuf_res, hash);

	switch (entry->state) {
	case VMW_CMDBUF_RES_ADD:
	vmw_cmdbuf_res_free(man, entry);
	break;
	case VMW_CMDBUF_RES_COMMITED:
	(void) drm_ht_remove_item(&man->resources, &entry->hash);
	list_del(&entry->head);
	entry->state = VMW_CMDBUF_RES_DEL;
	list_add_tail(&entry->head, list);
	break;
	default:
	BUG();
	break;
	}

	return 0;
	}

	/**
	* vmw_cmdbuf_res_man_create - Allocate a command buffer managed resource
	* manager.
	*
	* @dev_priv: Pointer to a struct vmw_private
	*
	* Allocates and initializes a command buffer managed resource manager. Returns
	* an error pointer on failure.
	*/
	struct vmw_cmdbuf_res_manager *
	vmw_cmdbuf_res_man_create(struct vmw_private *dev_priv)
	{
	struct vmw_cmdbuf_res_manager *man;
	int ret;

	man = kzalloc(sizeof(*man), GFP_KERNEL);
	if (man == NULL)
	return ERR_PTR(-ENOMEM);

	man->dev_priv = dev_priv;
	INIT_LIST_HEAD(&man->list);
	ret = drm_ht_create(&man->resources, VMW_CMDBUF_RES_MAN_HT_ORDER);
	if (ret == 0)
	return man;

	kfree(man);
	return ERR_PTR(ret);
	}

	/**
	* vmw_cmdbuf_res_man_destroy - Destroy a command buffer managed resource
	* manager.
	*
	* @man: Pointer to the manager to destroy.
	*
	* This function destroys a command buffer managed resource manager and
	* unreferences / frees all command buffer managed resources and -entries
	* associated with it.
	*/
	void vmw_cmdbuf_res_man_destroy(struct vmw_cmdbuf_res_manager *man)
	{
	struct vmw_cmdbuf_res entry, next;

	list_for_each_entry_safe(entry, next, &man->list, head)
	vmw_cmdbuf_res_free(man, entry);

	kfree(man);
	}

	/**
	*
	* vmw_cmdbuf_res_man_size - Return the size of a command buffer managed
	* resource manager
	*
	* Returns the approximate allocation size of a command buffer managed
	* resource manager.
	*/
	size_t vmw_cmdbuf_res_man_size(void)
	{
	static size_t res_man_size;

	if (unlikely(res_man_size == 0))
	res_man_size =
	ttm_round_pot(sizeof(struct vmw_cmdbuf_res_manager)) +
	ttm_round_pot(sizeof(struct hlist_head) <<
	VMW_CMDBUF_RES_MAN_HT_ORDER);

	return res_man_size;
	}