1/*	$NetBSD: vmwgfx_cmdbuf_res.c,v 1.3 2021/12/18 23:45:45 riastradh Exp $	*/
2
3// SPDX-License-Identifier: GPL-2.0 OR MIT
4/**************************************************************************
5 *
6 * Copyright 2014-2015 VMware, Inc., Palo Alto, CA., USA
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a
9 * copy of this software and associated documentation files (the
10 * "Software"), to deal in the Software without restriction, including
11 * without limitation the rights to use, copy, modify, merge, publish,
12 * distribute, sub license, and/or sell copies of the Software, and to
13 * permit persons to whom the Software is furnished to do so, subject to
14 * the following conditions:
15 *
16 * The above copyright notice and this permission notice (including the
17 * next paragraph) shall be included in all copies or substantial portions
18 * of the Software.
19 *
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
23 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
24 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
25 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
26 * USE OR OTHER DEALINGS IN THE SOFTWARE.
27 *
28 **************************************************************************/
29
30#include <sys/cdefs.h>
31__KERNEL_RCSID(0, "$NetBSD: vmwgfx_cmdbuf_res.c,v 1.3 2021/12/18 23:45:45 riastradh Exp $");
32
33#include "vmwgfx_drv.h"
34#include "vmwgfx_resource_priv.h"
35
36#define VMW_CMDBUF_RES_MAN_HT_ORDER 12
37
38/**
39 * struct vmw_cmdbuf_res - Command buffer managed resource entry.
40 *
41 * @res: Refcounted pointer to a struct vmw_resource.
42 * @hash: Hash entry for the manager hash table.
43 * @head: List head used either by the staging list or the manager list
44 * of commited resources.
45 * @state: Staging state of this resource entry.
46 * @man: Pointer to a resource manager for this entry.
47 */
48struct vmw_cmdbuf_res {
49	struct vmw_resource *res;
50	struct drm_hash_item hash;
51	struct list_head head;
52	enum vmw_cmdbuf_res_state state;
53	struct vmw_cmdbuf_res_manager *man;
54};
55
56/**
57 * struct vmw_cmdbuf_res_manager - Command buffer resource manager.
58 *
59 * @resources: Hash table containing staged and commited command buffer
60 * resources
61 * @list: List of commited command buffer resources.
62 * @dev_priv: Pointer to a device private structure.
63 *
64 * @resources and @list are protected by the cmdbuf mutex for now.
65 */
66struct vmw_cmdbuf_res_manager {
67	struct drm_open_hash resources;
68	struct list_head list;
69	struct vmw_private *dev_priv;
70};
71
72
73/**
74 * vmw_cmdbuf_res_lookup - Look up a command buffer resource
75 *
76 * @man: Pointer to the command buffer resource manager
77 * @resource_type: The resource type, that combined with the user key
78 * identifies the resource.
79 * @user_key: The user key.
80 *
81 * Returns a valid refcounted struct vmw_resource pointer on success,
82 * an error pointer on failure.
83 */
84struct vmw_resource *
85vmw_cmdbuf_res_lookup(struct vmw_cmdbuf_res_manager *man,
86		      enum vmw_cmdbuf_res_type res_type,
87		      u32 user_key)
88{
89	struct drm_hash_item *hash;
90	int ret;
91	unsigned long key = user_key | (res_type << 24);
92
93	ret = drm_ht_find_item(&man->resources, key, &hash);
94	if (unlikely(ret != 0))
95		return ERR_PTR(ret);
96
97	return drm_hash_entry(hash, struct vmw_cmdbuf_res, hash)->res;
98}
99
100/**
101 * vmw_cmdbuf_res_free - Free a command buffer resource.
102 *
103 * @man: Pointer to the command buffer resource manager
104 * @entry: Pointer to a struct vmw_cmdbuf_res.
105 *
106 * Frees a struct vmw_cmdbuf_res entry and drops its reference to the
107 * struct vmw_resource.
108 */
109static void vmw_cmdbuf_res_free(struct vmw_cmdbuf_res_manager *man,
110				struct vmw_cmdbuf_res *entry)
111{
112	list_del(&entry->head);
113	WARN_ON(drm_ht_remove_item(&man->resources, &entry->hash));
114	vmw_resource_unreference(&entry->res);
115	kfree(entry);
116}
117
118/**
119 * vmw_cmdbuf_res_commit - Commit a list of command buffer resource actions
120 *
121 * @list: Caller's list of command buffer resource actions.
122 *
123 * This function commits a list of command buffer resource
124 * additions or removals.
125 * It is typically called when the execbuf ioctl call triggering these
126 * actions has commited the fifo contents to the device.
127 */
128void vmw_cmdbuf_res_commit(struct list_head *list)
129{
130	struct vmw_cmdbuf_res *entry, *next;
131
132	list_for_each_entry_safe(entry, next, list, head) {
133		list_del(&entry->head);
134		if (entry->res->func->commit_notify)
135			entry->res->func->commit_notify(entry->res,
136							entry->state);
137		switch (entry->state) {
138		case VMW_CMDBUF_RES_ADD:
139			entry->state = VMW_CMDBUF_RES_COMMITTED;
140			list_add_tail(&entry->head, &entry->man->list);
141			break;
142		case VMW_CMDBUF_RES_DEL:
143			vmw_resource_unreference(&entry->res);
144			kfree(entry);
145			break;
146		default:
147			BUG();
148			break;
149		}
150	}
151}
152
153/**
154 * vmw_cmdbuf_res_revert - Revert a list of command buffer resource actions
155 *
156 * @man: Pointer to the command buffer resource manager
157 * @list: Caller's list of command buffer resource action
158 *
159 * This function reverts a list of command buffer resource
160 * additions or removals.
161 * It is typically called when the execbuf ioctl call triggering these
162 * actions failed for some reason, and the command stream was never
163 * submitted.
164 */
165void vmw_cmdbuf_res_revert(struct list_head *list)
166{
167	struct vmw_cmdbuf_res *entry, *next;
168	int ret;
169
170	list_for_each_entry_safe(entry, next, list, head) {
171		switch (entry->state) {
172		case VMW_CMDBUF_RES_ADD:
173			vmw_cmdbuf_res_free(entry->man, entry);
174			break;
175		case VMW_CMDBUF_RES_DEL:
176			ret = drm_ht_insert_item(&entry->man->resources,
177						 &entry->hash);
178			list_del(&entry->head);
179			list_add_tail(&entry->head, &entry->man->list);
180			entry->state = VMW_CMDBUF_RES_COMMITTED;
181			break;
182		default:
183			BUG();
184			break;
185		}
186	}
187}
188
189/**
190 * vmw_cmdbuf_res_add - Stage a command buffer managed resource for addition.
191 *
192 * @man: Pointer to the command buffer resource manager.
193 * @res_type: The resource type.
194 * @user_key: The user-space id of the resource.
195 * @res: Valid (refcount != 0) pointer to a struct vmw_resource.
196 * @list: The staging list.
197 *
198 * This function allocates a struct vmw_cmdbuf_res entry and adds the
199 * resource to the hash table of the manager identified by @man. The
200 * entry is then put on the staging list identified by @list.
201 */
202int vmw_cmdbuf_res_add(struct vmw_cmdbuf_res_manager *man,
203		       enum vmw_cmdbuf_res_type res_type,
204		       u32 user_key,
205		       struct vmw_resource *res,
206		       struct list_head *list)
207{
208	struct vmw_cmdbuf_res *cres;
209	int ret;
210
211	cres = kzalloc(sizeof(*cres), GFP_KERNEL);
212	if (unlikely(!cres))
213		return -ENOMEM;
214
215	cres->hash.key = user_key | (res_type << 24);
216	ret = drm_ht_insert_item(&man->resources, &cres->hash);
217	if (unlikely(ret != 0)) {
218		kfree(cres);
219		goto out_invalid_key;
220	}
221
222	cres->state = VMW_CMDBUF_RES_ADD;
223	cres->res = vmw_resource_reference(res);
224	cres->man = man;
225	list_add_tail(&cres->head, list);
226
227out_invalid_key:
228	return ret;
229}
230
231/**
232 * vmw_cmdbuf_res_remove - Stage a command buffer managed resource for removal.
233 *
234 * @man: Pointer to the command buffer resource manager.
235 * @res_type: The resource type.
236 * @user_key: The user-space id of the resource.
237 * @list: The staging list.
238 * @res_p: If the resource is in an already committed state, points to the
239 * struct vmw_resource on successful return. The pointer will be
240 * non ref-counted.
241 *
242 * This function looks up the struct vmw_cmdbuf_res entry from the manager
243 * hash table and, if it exists, removes it. Depending on its current staging
244 * state it then either removes the entry from the staging list or adds it
245 * to it with a staging state of removal.
246 */
247int vmw_cmdbuf_res_remove(struct vmw_cmdbuf_res_manager *man,
248			  enum vmw_cmdbuf_res_type res_type,
249			  u32 user_key,
250			  struct list_head *list,
251			  struct vmw_resource **res_p)
252{
253	struct vmw_cmdbuf_res *entry;
254	struct drm_hash_item *hash;
255	int ret;
256
257	ret = drm_ht_find_item(&man->resources, user_key | (res_type << 24),
258			       &hash);
259	if (likely(ret != 0))
260		return -EINVAL;
261
262	entry = drm_hash_entry(hash, struct vmw_cmdbuf_res, hash);
263
264	switch (entry->state) {
265	case VMW_CMDBUF_RES_ADD:
266		vmw_cmdbuf_res_free(man, entry);
267		*res_p = NULL;
268		break;
269	case VMW_CMDBUF_RES_COMMITTED:
270		(void) drm_ht_remove_item(&man->resources, &entry->hash);
271		list_del(&entry->head);
272		entry->state = VMW_CMDBUF_RES_DEL;
273		list_add_tail(&entry->head, list);
274		*res_p = entry->res;
275		break;
276	default:
277		BUG();
278		break;
279	}
280
281	return 0;
282}
283
284/**
285 * vmw_cmdbuf_res_man_create - Allocate a command buffer managed resource
286 * manager.
287 *
288 * @dev_priv: Pointer to a struct vmw_private
289 *
290 * Allocates and initializes a command buffer managed resource manager. Returns
291 * an error pointer on failure.
292 */
293struct vmw_cmdbuf_res_manager *
294vmw_cmdbuf_res_man_create(struct vmw_private *dev_priv)
295{
296	struct vmw_cmdbuf_res_manager *man;
297	int ret;
298
299	man = kzalloc(sizeof(*man), GFP_KERNEL);
300	if (!man)
301		return ERR_PTR(-ENOMEM);
302
303	man->dev_priv = dev_priv;
304	INIT_LIST_HEAD(&man->list);
305	ret = drm_ht_create(&man->resources, VMW_CMDBUF_RES_MAN_HT_ORDER);
306	if (ret == 0)
307		return man;
308
309	kfree(man);
310	return ERR_PTR(ret);
311}
312
313/**
314 * vmw_cmdbuf_res_man_destroy - Destroy a command buffer managed resource
315 * manager.
316 *
317 * @man: Pointer to the  manager to destroy.
318 *
319 * This function destroys a command buffer managed resource manager and
320 * unreferences / frees all command buffer managed resources and -entries
321 * associated with it.
322 */
323void vmw_cmdbuf_res_man_destroy(struct vmw_cmdbuf_res_manager *man)
324{
325	struct vmw_cmdbuf_res *entry, *next;
326
327	list_for_each_entry_safe(entry, next, &man->list, head)
328		vmw_cmdbuf_res_free(man, entry);
329
330	drm_ht_remove(&man->resources);
331	kfree(man);
332}
333
334/**
335 *
336 * vmw_cmdbuf_res_man_size - Return the size of a command buffer managed
337 * resource manager
338 *
339 * Returns the approximate allocation size of a command buffer managed
340 * resource manager.
341 */
342size_t vmw_cmdbuf_res_man_size(void)
343{
344	static size_t res_man_size;
345
346	if (unlikely(res_man_size == 0))
347		res_man_size =
348			ttm_round_pot(sizeof(struct vmw_cmdbuf_res_manager)) +
349			ttm_round_pot(sizeof(struct hlist_head) <<
350				      VMW_CMDBUF_RES_MAN_HT_ORDER);
351
352	return res_man_size;
353}
354