1/*	$NetBSD: drm_gem.h,v 1.12 2021/12/19 10:38:23 riastradh Exp $	*/
2
3#ifndef __DRM_GEM_H__
4#define __DRM_GEM_H__
5
6/*
7 * GEM Graphics Execution Manager Driver Interfaces
8 *
9 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
10 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
11 * Copyright (c) 2009-2010, Code Aurora Forum.
12 * All rights reserved.
13 * Copyright �� 2014 Intel Corporation
14 *   Daniel Vetter <daniel.vetter@ffwll.ch>
15 *
16 * Author: Rickard E. (Rik) Faith <faith@valinux.com>
17 * Author: Gareth Hughes <gareth@valinux.com>
18 *
19 * Permission is hereby granted, free of charge, to any person obtaining a
20 * copy of this software and associated documentation files (the "Software"),
21 * to deal in the Software without restriction, including without limitation
22 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
23 * and/or sell copies of the Software, and to permit persons to whom the
24 * Software is furnished to do so, subject to the following conditions:
25 *
26 * The above copyright notice and this permission notice (including the next
27 * paragraph) shall be included in all copies or substantial portions of the
28 * Software.
29 *
30 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
31 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
32 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
33 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
34 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
35 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
36 * OTHER DEALINGS IN THE SOFTWARE.
37 */
38
39#ifdef __NetBSD__
40#include <uvm/uvm.h>
41#endif
42
43#include <linux/types.h>
44#include <linux/kref.h>
45#include <linux/dma-resv.h>
46
47#include <drm/drm_device.h>
48#include <drm/drm_print.h>
49#include <drm/drm_vma_manager.h>
50#undef free
51
52struct drm_gem_object;
53struct xarray;
54
55/**
56 * struct drm_gem_object_funcs - GEM object functions
57 */
58struct drm_gem_object_funcs {
59	/**
60	 * @free:
61	 *
62	 * Deconstructor for drm_gem_objects.
63	 *
64	 * This callback is mandatory.
65	 */
66	void (*free)(struct drm_gem_object *obj);
67
68	/**
69	 * @open:
70	 *
71	 * Called upon GEM handle creation.
72	 *
73	 * This callback is optional.
74	 */
75	int (*open)(struct drm_gem_object *obj, struct drm_file *file);
76
77	/**
78	 * @close:
79	 *
80	 * Called upon GEM handle release.
81	 *
82	 * This callback is optional.
83	 */
84	void (*close)(struct drm_gem_object *obj, struct drm_file *file);
85
86	/**
87	 * @print_info:
88	 *
89	 * If driver subclasses struct &drm_gem_object, it can implement this
90	 * optional hook for printing additional driver specific info.
91	 *
92	 * drm_printf_indent() should be used in the callback passing it the
93	 * indent argument.
94	 *
95	 * This callback is called from drm_gem_print_info().
96	 *
97	 * This callback is optional.
98	 */
99	void (*print_info)(struct drm_printer *p, unsigned int indent,
100			   const struct drm_gem_object *obj);
101
102	/**
103	 * @export:
104	 *
105	 * Export backing buffer as a &dma_buf.
106	 * If this is not set drm_gem_prime_export() is used.
107	 *
108	 * This callback is optional.
109	 */
110	struct dma_buf *(*export)(struct drm_gem_object *obj, int flags);
111
112	/**
113	 * @pin:
114	 *
115	 * Pin backing buffer in memory. Used by the drm_gem_map_attach() helper.
116	 *
117	 * This callback is optional.
118	 */
119	int (*pin)(struct drm_gem_object *obj);
120
121	/**
122	 * @unpin:
123	 *
124	 * Unpin backing buffer. Used by the drm_gem_map_detach() helper.
125	 *
126	 * This callback is optional.
127	 */
128	void (*unpin)(struct drm_gem_object *obj);
129
130	/**
131	 * @get_sg_table:
132	 *
133	 * Returns a Scatter-Gather table representation of the buffer.
134	 * Used when exporting a buffer by the drm_gem_map_dma_buf() helper.
135	 * Releasing is done by calling dma_unmap_sg_attrs() and sg_free_table()
136	 * in drm_gem_unmap_buf(), therefore these helpers and this callback
137	 * here cannot be used for sg tables pointing at driver private memory
138	 * ranges.
139	 *
140	 * See also drm_prime_pages_to_sg().
141	 */
142	struct sg_table *(*get_sg_table)(struct drm_gem_object *obj);
143
144	/**
145	 * @vmap:
146	 *
147	 * Returns a virtual address for the buffer. Used by the
148	 * drm_gem_dmabuf_vmap() helper.
149	 *
150	 * This callback is optional.
151	 */
152	void *(*vmap)(struct drm_gem_object *obj);
153
154	/**
155	 * @vunmap:
156	 *
157	 * Releases the the address previously returned by @vmap. Used by the
158	 * drm_gem_dmabuf_vunmap() helper.
159	 *
160	 * This callback is optional.
161	 */
162	void (*vunmap)(struct drm_gem_object *obj, void *vaddr);
163
164	/**
165	 * @mmap:
166	 *
167	 * Handle mmap() of the gem object, setup vma accordingly.
168	 *
169	 * This callback is optional.
170	 *
171	 * The callback is used by by both drm_gem_mmap_obj() and
172	 * drm_gem_prime_mmap().  When @mmap is present @vm_ops is not
173	 * used, the @mmap callback must set vma->vm_ops instead.
174	 */
175#ifdef __NetBSD__
176	int (*mmap)(struct drm_gem_object *, off_t *, size_t, int,
177	    int *, int *, struct uvm_object **, int *);
178#else
179	int (*mmap)(struct drm_gem_object *obj, struct vm_area_struct *vma);
180#endif
181
182	/**
183	 * @vm_ops:
184	 *
185	 * Virtual memory operations used with mmap.
186	 *
187	 * This is optional but necessary for mmap support.
188	 */
189	const struct vm_operations_struct *vm_ops;
190};
191
192/**
193 * struct drm_gem_object - GEM buffer object
194 *
195 * This structure defines the generic parts for GEM buffer objects, which are
196 * mostly around handling mmap and userspace handles.
197 *
198 * Buffer objects are often abbreviated to BO.
199 */
200struct drm_gem_object {
201	/**
202	 * @refcount:
203	 *
204	 * Reference count of this object
205	 *
206	 * Please use drm_gem_object_get() to acquire and drm_gem_object_put()
207	 * or drm_gem_object_put_unlocked() to release a reference to a GEM
208	 * buffer object.
209	 */
210	struct kref refcount;
211
212	/**
213	 * @handle_count:
214	 *
215	 * This is the GEM file_priv handle count of this object.
216	 *
217	 * Each handle also holds a reference. Note that when the handle_count
218	 * drops to 0 any global names (e.g. the id in the flink namespace) will
219	 * be cleared.
220	 *
221	 * Protected by &drm_device.object_name_lock.
222	 */
223	unsigned handle_count;
224
225	/**
226	 * @dev: DRM dev this object belongs to.
227	 */
228	struct drm_device *dev;
229
230#ifdef __NetBSD__
231	/* UVM anonymous object for shared memory mappings.  */
232	struct uvm_object *filp;
233
234	/* UVM object with custom pager ops for device memory mappings.  */
235	struct uvm_object gemo_uvmobj;
236#else
237	/**
238	 * @filp:
239	 *
240	 * SHMEM file node used as backing storage for swappable buffer objects.
241	 * GEM also supports driver private objects with driver-specific backing
242	 * storage (contiguous CMA memory, special reserved blocks). In this
243	 * case @filp is NULL.
244	 */
245	struct file *filp;
246#endif
247
248	/**
249	 * @vma_node:
250	 *
251	 * Mapping info for this object to support mmap. Drivers are supposed to
252	 * allocate the mmap offset using drm_gem_create_mmap_offset(). The
253	 * offset itself can be retrieved using drm_vma_node_offset_addr().
254	 *
255	 * Memory mapping itself is handled by drm_gem_mmap(), which also checks
256	 * that userspace is allowed to access the object.
257	 */
258	struct drm_vma_offset_node vma_node;
259
260	/**
261	 * @size:
262	 *
263	 * Size of the object, in bytes.  Immutable over the object's
264	 * lifetime.
265	 */
266	size_t size;
267
268	/**
269	 * @name:
270	 *
271	 * Global name for this object, starts at 1. 0 means unnamed.
272	 * Access is covered by &drm_device.object_name_lock. This is used by
273	 * the GEM_FLINK and GEM_OPEN ioctls.
274	 */
275	int name;
276
277	/**
278	 * @dma_buf:
279	 *
280	 * dma-buf associated with this GEM object.
281	 *
282	 * Pointer to the dma-buf associated with this gem object (either
283	 * through importing or exporting). We break the resulting reference
284	 * loop when the last gem handle for this object is released.
285	 *
286	 * Protected by &drm_device.object_name_lock.
287	 */
288	struct dma_buf *dma_buf;
289
290	/**
291	 * @import_attach:
292	 *
293	 * dma-buf attachment backing this object.
294	 *
295	 * Any foreign dma_buf imported as a gem object has this set to the
296	 * attachment point for the device. This is invariant over the lifetime
297	 * of a gem object.
298	 *
299	 * The &drm_driver.gem_free_object callback is responsible for cleaning
300	 * up the dma_buf attachment and references acquired at import time.
301	 *
302	 * Note that the drm gem/prime core does not depend upon drivers setting
303	 * this field any more. So for drivers where this doesn't make sense
304	 * (e.g. virtual devices or a displaylink behind an usb bus) they can
305	 * simply leave it as NULL.
306	 */
307	struct dma_buf_attachment *import_attach;
308
309	/**
310	 * @resv:
311	 *
312	 * Pointer to reservation object associated with the this GEM object.
313	 *
314	 * Normally (@resv == &@_resv) except for imported GEM objects.
315	 */
316	struct dma_resv *resv;
317
318	/**
319	 * @_resv:
320	 *
321	 * A reservation object for this GEM object.
322	 *
323	 * This is unused for imported GEM objects.
324	 */
325	struct dma_resv _resv;
326
327	/**
328	 * @funcs:
329	 *
330	 * Optional GEM object functions. If this is set, it will be used instead of the
331	 * corresponding &drm_driver GEM callbacks.
332	 *
333	 * New drivers should use this.
334	 *
335	 */
336	const struct drm_gem_object_funcs *funcs;
337};
338
339/**
340 * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
341 * @name: name for the generated structure
342 *
343 * This macro autogenerates a suitable &struct file_operations for GEM based
344 * drivers, which can be assigned to &drm_driver.fops. Note that this structure
345 * cannot be shared between drivers, because it contains a reference to the
346 * current module using THIS_MODULE.
347 *
348 * Note that the declaration is already marked as static - if you need a
349 * non-static version of this you're probably doing it wrong and will break the
350 * THIS_MODULE reference by accident.
351 */
352#define DEFINE_DRM_GEM_FOPS(name) \
353	static const struct file_operations name = {\
354		.owner		= THIS_MODULE,\
355		.open		= drm_open,\
356		.release	= drm_release,\
357		.unlocked_ioctl	= drm_ioctl,\
358		.compat_ioctl	= drm_compat_ioctl,\
359		.poll		= drm_poll,\
360		.read		= drm_read,\
361		.llseek		= noop_llseek,\
362		.mmap		= drm_gem_mmap,\
363	}
364
365void drm_gem_object_release(struct drm_gem_object *obj);
366void drm_gem_object_free(struct kref *kref);
367int drm_gem_object_init(struct drm_device *dev,
368			struct drm_gem_object *obj, size_t size);
369void drm_gem_private_object_init(struct drm_device *dev,
370				 struct drm_gem_object *obj, size_t size);
371#ifdef __NetBSD__
372void drm_gem_pager_reference(struct uvm_object *);
373void drm_gem_pager_detach(struct uvm_object *);
374int drm_gem_mmap_object(struct drm_device *, off_t, size_t, int,
375    struct uvm_object **, voff_t *, struct file *);
376int drm_gem_or_legacy_mmap_object(struct drm_device *, off_t, size_t, int,
377    struct uvm_object **, voff_t *, struct file *);
378#else
379void drm_gem_vm_open(struct vm_area_struct *vma);
380void drm_gem_vm_close(struct vm_area_struct *vma);
381int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
382		     struct vm_area_struct *vma);
383int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
384#endif
385
386/**
387 * drm_gem_object_get - acquire a GEM buffer object reference
388 * @obj: GEM buffer object
389 *
390 * This function acquires an additional reference to @obj. It is illegal to
391 * call this without already holding a reference. No locks required.
392 */
393static inline void drm_gem_object_get(struct drm_gem_object *obj)
394{
395	kref_get(&obj->refcount);
396}
397
398/**
399 * __drm_gem_object_put - raw function to release a GEM buffer object reference
400 * @obj: GEM buffer object
401 *
402 * This function is meant to be used by drivers which are not encumbered with
403 * &drm_device.struct_mutex legacy locking and which are using the
404 * gem_free_object_unlocked callback. It avoids all the locking checks and
405 * locking overhead of drm_gem_object_put() and drm_gem_object_put_unlocked().
406 *
407 * Drivers should never call this directly in their code. Instead they should
408 * wrap it up into a ``driver_gem_object_put(struct driver_gem_object *obj)``
409 * wrapper function, and use that. Shared code should never call this, to
410 * avoid breaking drivers by accident which still depend upon
411 * &drm_device.struct_mutex locking.
412 */
413static inline void
414__drm_gem_object_put(struct drm_gem_object *obj)
415{
416	kref_put(&obj->refcount, drm_gem_object_free);
417}
418
419void drm_gem_object_put_unlocked(struct drm_gem_object *obj);
420void drm_gem_object_put(struct drm_gem_object *obj);
421
422int drm_gem_handle_create(struct drm_file *file_priv,
423			  struct drm_gem_object *obj,
424			  u32 *handlep);
425int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
426
427
428void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
429int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
430int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
431
432struct page **drm_gem_get_pages(struct drm_gem_object *obj);
433void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
434		bool dirty, bool accessed);
435
436int drm_gem_objects_lookup(struct drm_file *filp, void __user *bo_handles,
437			   int count, struct drm_gem_object ***objs_out);
438struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
439long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
440				    bool wait_all, unsigned long timeout);
441int drm_gem_lock_reservations(struct drm_gem_object **objs, int count,
442			      struct ww_acquire_ctx *acquire_ctx);
443void drm_gem_unlock_reservations(struct drm_gem_object **objs, int count,
444				 struct ww_acquire_ctx *acquire_ctx);
445int drm_gem_fence_array_add(struct xarray *fence_array,
446			    struct dma_fence *fence);
447int drm_gem_fence_array_add_implicit(struct xarray *fence_array,
448				     struct drm_gem_object *obj,
449				     bool write);
450int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
451			    u32 handle, u64 *offset);
452int drm_gem_dumb_destroy(struct drm_file *file,
453			 struct drm_device *dev,
454			 uint32_t handle);
455
456#define	free(addr, type)		kern_free(addr)
457
458#endif /* __DRM_GEM_H__ */
459