2 * Copyright (c) 2011 The FreeBSD Foundation
5 * This software was developed by Konstantin Belousov under sponsorship from
6 * the FreeBSD Foundation.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * $FreeBSD: head/sys/dev/drm2/drm_gem.c 247835 2013-03-05 09:49:34Z kib $"
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/limits.h>
38 #include <sys/mutex.h>
42 #include <vm/vm_page.h>
47 * We make up offsets for buffer objects so we can recognize them at
51 /* pgoff in mmap is an unsigned long, so we need to make sure that
52 * the faked up offset will fit
55 #if ULONG_MAX == UINT64_MAX
56 #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1)
57 #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16)
59 #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1)
60 #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16)
64 * Initialize the GEM device fields
68 drm_gem_init(struct drm_device *dev)
70 struct drm_gem_mm *mm;
72 lockinit(&dev->object_name_lock, "objnam", 0, LK_CANRECURSE);
73 idr_init(&dev->object_name_idr);
75 mm = kmalloc(sizeof(*mm), DRM_MEM_DRIVER, M_WAITOK);
77 DRM_ERROR("out of memory\n");
83 if (drm_ht_create(&mm->offset_hash, 12)) {
84 drm_free(mm, DRM_MEM_DRIVER);
88 mm->idxunr = new_unrhdr(0, DRM_GEM_MAX_IDX, NULL);
93 drm_gem_destroy(struct drm_device *dev)
95 struct drm_gem_mm *mm = dev->mm_private;
97 drm_ht_remove(&mm->offset_hash);
98 delete_unrhdr(mm->idxunr);
99 drm_free(mm, DRM_MEM_DRIVER);
100 dev->mm_private = NULL;
104 * Initialize an already allocated GEM object of the specified size with
105 * shmfs backing store.
107 int drm_gem_object_init(struct drm_device *dev,
108 struct drm_gem_object *obj, size_t size)
111 KASSERT((size & (PAGE_SIZE - 1)) == 0,
112 ("Bad size %ju", (uintmax_t)size));
115 obj->vm_obj = default_pager_alloc(NULL, size,
116 VM_PROT_READ | VM_PROT_WRITE, 0);
118 kref_init(&obj->refcount);
119 atomic_set(&obj->handle_count, 0);
126 * Initialize an already allocated GEM object of the specified size with
127 * no GEM provided backing store. Instead the caller is responsible for
128 * backing the object and handling it.
130 int drm_gem_private_object_init(struct drm_device *dev,
131 struct drm_gem_object *obj, size_t size)
134 KASSERT((size & (PAGE_SIZE - 1)) == 0,
135 ("Bad size %ju", (uintmax_t)size));
140 kref_init(&obj->refcount);
141 atomic_set(&obj->handle_count, 0);
148 struct drm_gem_object *
149 drm_gem_object_alloc(struct drm_device *dev, size_t size)
151 struct drm_gem_object *obj;
153 obj = kmalloc(sizeof(*obj), DRM_MEM_DRIVER, M_WAITOK | M_ZERO);
154 if (drm_gem_object_init(dev, obj, size) != 0)
157 if (dev->driver->gem_init_object != NULL &&
158 dev->driver->gem_init_object(obj) != 0)
162 vm_object_deallocate(obj->vm_obj);
164 drm_free(obj, DRM_MEM_DRIVER);
169 * Called after the last reference to the object has been lost.
170 * Must be called holding struct_ mutex
175 drm_gem_object_free(struct kref *kref)
177 struct drm_gem_object *obj = (struct drm_gem_object *) kref;
178 struct drm_device *dev = obj->dev;
180 DRM_LOCK_ASSERT(dev);
181 if (dev->driver->gem_free_object != NULL)
182 dev->driver->gem_free_object(obj);
185 static void drm_gem_object_ref_bug(struct kref *list_kref)
191 * Called after the last handle to the object has been closed
193 * Removes any name for the object. Note that this must be
194 * called before drm_gem_object_free or we'll be touching
197 void drm_gem_object_handle_free(struct drm_gem_object *obj)
199 struct drm_device *dev = obj->dev;
201 /* Remove any name for this object */
202 lockmgr(&dev->object_name_lock, LK_EXCLUSIVE);
204 idr_remove(&dev->object_name_idr, obj->name);
206 lockmgr(&dev->object_name_lock, LK_RELEASE);
208 * The object name held a reference to this object, drop
211 * This cannot be the last reference, since the handle holds one too.
213 kref_put(&obj->refcount, drm_gem_object_ref_bug);
215 lockmgr(&dev->object_name_lock, LK_RELEASE);
220 * Removes the mapping from handle to filp for this object.
223 drm_gem_handle_delete(struct drm_file *filp, u32 handle)
225 struct drm_device *dev;
226 struct drm_gem_object *obj;
228 /* This is gross. The idr system doesn't let us try a delete and
229 * return an error code. It just spews if you fail at deleting.
230 * So, we have to grab a lock around finding the object and then
231 * doing the delete on it and dropping the refcount, or the user
232 * could race us to double-decrement the refcount and cause a
233 * use-after-free later. Given the frequency of our handle lookups,
234 * we may want to use ida for number allocation and a hash table
235 * for the pointers, anyway.
237 lockmgr(&filp->table_lock, LK_EXCLUSIVE);
239 /* Check if we currently have a reference on the object */
240 obj = idr_find(&filp->object_idr, handle);
242 lockmgr(&filp->table_lock, LK_RELEASE);
247 /* Release reference and decrement refcount. */
248 idr_remove(&filp->object_idr, handle);
249 lockmgr(&filp->table_lock, LK_RELEASE);
251 if (dev->driver->gem_close_object)
252 dev->driver->gem_close_object(obj, filp);
253 drm_gem_object_handle_unreference_unlocked(obj);
259 * Create a handle for this object. This adds a handle reference
260 * to the object, which includes a regular reference count. Callers
261 * will likely want to dereference the object afterwards.
264 drm_gem_handle_create(struct drm_file *file_priv,
265 struct drm_gem_object *obj,
268 struct drm_device *dev = obj->dev;
272 * Get the user-visible handle using idr.
275 /* ensure there is space available to allocate a handle */
276 if (idr_pre_get(&file_priv->object_idr, GFP_KERNEL) == 0)
279 /* do the allocation under our spinlock */
280 lockmgr(&file_priv->table_lock, LK_EXCLUSIVE);
281 ret = idr_get_new_above(&file_priv->object_idr, obj, 1, (int *)handlep);
282 lockmgr(&file_priv->table_lock, LK_RELEASE);
288 drm_gem_object_handle_reference(obj);
290 if (dev->driver->gem_open_object) {
291 ret = dev->driver->gem_open_object(obj, file_priv);
293 drm_gem_handle_delete(file_priv, *handlep);
301 /** Returns a reference to the object named by the handle. */
302 struct drm_gem_object *
303 drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp,
306 struct drm_gem_object *obj;
308 lockmgr(&filp->table_lock, LK_EXCLUSIVE);
310 /* Check if we currently have a reference on the object */
311 obj = idr_find(&filp->object_idr, handle);
313 lockmgr(&filp->table_lock, LK_RELEASE);
317 drm_gem_object_reference(obj);
319 lockmgr(&filp->table_lock, LK_RELEASE);
325 drm_gem_close_ioctl(struct drm_device *dev, void *data,
326 struct drm_file *file_priv)
328 struct drm_gem_close *args;
330 if (!drm_core_check_feature(dev, DRIVER_GEM))
334 return (drm_gem_handle_delete(file_priv, args->handle));
338 * Create a global name for an object, returning the name.
340 * Note that the name does not hold a reference; when the object
341 * is freed, the name goes away.
344 drm_gem_flink_ioctl(struct drm_device *dev, void *data,
345 struct drm_file *file_priv)
347 struct drm_gem_flink *args = data;
348 struct drm_gem_object *obj;
351 if (!drm_core_check_feature(dev, DRIVER_GEM))
354 obj = drm_gem_object_lookup(dev, file_priv, args->handle);
359 if (idr_pre_get(&dev->object_name_idr, GFP_KERNEL) == 0) {
364 lockmgr(&dev->object_name_lock, LK_EXCLUSIVE);
366 ret = idr_get_new_above(&dev->object_name_idr, obj, 1,
368 args->name = (uint64_t) obj->name;
369 lockmgr(&dev->object_name_lock, LK_RELEASE);
376 /* Allocate a reference for the name table. */
377 drm_gem_object_reference(obj);
379 args->name = (uint64_t) obj->name;
380 lockmgr(&dev->object_name_lock, LK_RELEASE);
385 drm_gem_object_unreference_unlocked(obj);
390 * Open an object using the global name, returning a handle and the size.
392 * This handle (of course) holds a reference to the object, so the object
393 * will not go away until the handle is deleted.
396 drm_gem_open_ioctl(struct drm_device *dev, void *data,
397 struct drm_file *file_priv)
399 struct drm_gem_open *args = data;
400 struct drm_gem_object *obj;
405 if (!drm_core_check_feature(dev, DRIVER_GEM))
407 if (!(dev->driver->driver_features & DRIVER_GEM))
410 lockmgr(&dev->object_name_lock, LK_EXCLUSIVE);
411 obj = idr_find(&dev->object_name_idr, (int) args->name);
413 drm_gem_object_reference(obj);
414 lockmgr(&dev->object_name_lock, LK_RELEASE);
418 ret = drm_gem_handle_create(file_priv, obj, &handle);
419 drm_gem_object_unreference_unlocked(obj);
423 args->handle = handle;
424 args->size = obj->size;
430 * Called at device open time, sets up the structure for handling refcounting
434 drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
436 idr_init(&file_private->object_idr);
437 lockinit(&file_private->table_lock, "fptab", 0, LK_CANRECURSE);
441 * Called at device close to release the file's
442 * handle references on objects.
445 drm_gem_object_release_handle(int id, void *ptr, void *data)
447 struct drm_file *file_priv = data;
448 struct drm_gem_object *obj = ptr;
449 struct drm_device *dev = obj->dev;
451 if (dev->driver->gem_close_object)
452 dev->driver->gem_close_object(obj, file_priv);
454 drm_gem_object_handle_unreference_unlocked(obj);
460 drm_gem_object_release(struct drm_gem_object *obj)
464 * obj->vm_obj can be NULL for private gem objects.
466 vm_object_deallocate(obj->vm_obj);
470 * Called at close time when the filp is going away.
472 * Releases any remaining references on objects by this filp.
475 drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
477 idr_for_each(&file_private->object_idr,
478 &drm_gem_object_release_handle, file_private);
480 idr_remove_all(&file_private->object_idr);
481 idr_destroy(&file_private->object_idr);
484 static struct drm_gem_object *
485 drm_gem_object_from_offset(struct drm_device *dev, vm_ooffset_t offset)
487 struct drm_gem_object *obj;
488 struct drm_gem_mm *mm;
489 struct drm_hash_item *map_list;
491 if ((offset & DRM_GEM_MAPPING_MASK) != DRM_GEM_MAPPING_KEY)
493 offset &= ~DRM_GEM_MAPPING_KEY;
494 mm = dev->mm_private;
495 if (drm_ht_find_item(&mm->offset_hash, DRM_GEM_MAPPING_IDX(offset),
497 DRM_DEBUG("drm_gem_object_from_offset: offset 0x%jx obj not found\n",
501 obj = container_of(map_list, struct drm_gem_object, map_list);
506 drm_gem_create_mmap_offset(struct drm_gem_object *obj)
508 struct drm_device *dev;
509 struct drm_gem_mm *mm;
515 mm = dev->mm_private;
518 obj->map_list.key = alloc_unr(mm->idxunr);
519 ret = drm_ht_insert_item(&mm->offset_hash, &obj->map_list);
521 DRM_ERROR("failed to add to map hash\n");
522 free_unr(mm->idxunr, obj->map_list.key);
530 drm_gem_free_mmap_offset(struct drm_gem_object *obj)
532 struct drm_hash_item *list;
533 struct drm_gem_mm *mm;
537 mm = obj->dev->mm_private;
538 list = &obj->map_list;
540 drm_ht_remove_item(&mm->offset_hash, list);
541 free_unr(mm->idxunr, list->key);
546 drm_gem_mmap_single(struct drm_device *dev, vm_ooffset_t *offset, vm_size_t size,
547 struct vm_object **obj_res, int nprot)
549 struct drm_gem_object *gem_obj;
550 struct vm_object *vm_obj;
553 gem_obj = drm_gem_object_from_offset(dev, *offset);
554 if (gem_obj == NULL) {
558 drm_gem_object_reference(gem_obj);
560 vm_obj = cdev_pager_allocate(gem_obj, OBJT_MGTDEVICE,
561 dev->driver->gem_pager_ops, size, nprot,
562 DRM_GEM_MAPPING_MAPOFF(*offset), curthread->td_ucred);
563 if (vm_obj == NULL) {
564 drm_gem_object_unreference_unlocked(gem_obj);
567 *offset = DRM_GEM_MAPPING_MAPOFF(*offset);
573 drm_gem_pager_dtr(void *handle)
575 struct drm_gem_object *obj;
576 struct drm_device *dev;
582 drm_gem_free_mmap_offset(obj);
583 drm_gem_object_unreference(obj);