drm_gem_vm.c revision 1.3.4.2 1 1.3.4.2 yamt /* $NetBSD: drm_gem_vm.c,v 1.3.4.2 2014/05/22 11:40:55 yamt Exp $ */
2 1.3.4.2 yamt
3 1.3.4.2 yamt /*-
4 1.3.4.2 yamt * Copyright (c) 2013 The NetBSD Foundation, Inc.
5 1.3.4.2 yamt * All rights reserved.
6 1.3.4.2 yamt *
7 1.3.4.2 yamt * This code is derived from software contributed to The NetBSD Foundation
8 1.3.4.2 yamt * by Taylor R. Campbell.
9 1.3.4.2 yamt *
10 1.3.4.2 yamt * Redistribution and use in source and binary forms, with or without
11 1.3.4.2 yamt * modification, are permitted provided that the following conditions
12 1.3.4.2 yamt * are met:
13 1.3.4.2 yamt * 1. Redistributions of source code must retain the above copyright
14 1.3.4.2 yamt * notice, this list of conditions and the following disclaimer.
15 1.3.4.2 yamt * 2. Redistributions in binary form must reproduce the above copyright
16 1.3.4.2 yamt * notice, this list of conditions and the following disclaimer in the
17 1.3.4.2 yamt * documentation and/or other materials provided with the distribution.
18 1.3.4.2 yamt *
19 1.3.4.2 yamt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 1.3.4.2 yamt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 1.3.4.2 yamt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 1.3.4.2 yamt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 1.3.4.2 yamt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 1.3.4.2 yamt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 1.3.4.2 yamt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 1.3.4.2 yamt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 1.3.4.2 yamt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 1.3.4.2 yamt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 1.3.4.2 yamt * POSSIBILITY OF SUCH DAMAGE.
30 1.3.4.2 yamt */
31 1.3.4.2 yamt
32 1.3.4.2 yamt #include <sys/cdefs.h>
33 1.3.4.2 yamt __KERNEL_RCSID(0, "$NetBSD: drm_gem_vm.c,v 1.3.4.2 2014/05/22 11:40:55 yamt Exp $");
34 1.3.4.2 yamt
35 1.3.4.2 yamt #include <sys/types.h>
36 1.3.4.2 yamt
37 1.3.4.2 yamt #include <uvm/uvm_extern.h>
38 1.3.4.2 yamt
39 1.3.4.2 yamt #include <drm/drmP.h>
40 1.3.4.2 yamt
41 1.3.4.2 yamt static int drm_gem_mmap_object_locked(struct drm_device *, off_t, size_t,
42 1.3.4.2 yamt int, struct uvm_object **, voff_t *);
43 1.3.4.2 yamt
44 1.3.4.2 yamt void
45 1.3.4.2 yamt drm_gem_pager_reference(struct uvm_object *uobj)
46 1.3.4.2 yamt {
47 1.3.4.2 yamt struct drm_gem_object *const obj = container_of(uobj,
48 1.3.4.2 yamt struct drm_gem_object, gemo_uvmobj);
49 1.3.4.2 yamt
50 1.3.4.2 yamt drm_gem_object_reference(obj);
51 1.3.4.2 yamt }
52 1.3.4.2 yamt
53 1.3.4.2 yamt void
54 1.3.4.2 yamt drm_gem_pager_detach(struct uvm_object *uobj)
55 1.3.4.2 yamt {
56 1.3.4.2 yamt struct drm_gem_object *const obj = container_of(uobj,
57 1.3.4.2 yamt struct drm_gem_object, gemo_uvmobj);
58 1.3.4.2 yamt
59 1.3.4.2 yamt drm_gem_object_unreference_unlocked(obj);
60 1.3.4.2 yamt }
61 1.3.4.2 yamt
62 1.3.4.2 yamt int
63 1.3.4.2 yamt drm_gem_mmap_object(struct drm_device *dev, off_t byte_offset, size_t nbytes,
64 1.3.4.2 yamt int prot, struct uvm_object **uobjp, voff_t *uoffsetp)
65 1.3.4.2 yamt {
66 1.3.4.2 yamt int ret;
67 1.3.4.2 yamt
68 1.3.4.2 yamt mutex_lock(&dev->struct_mutex);
69 1.3.4.2 yamt ret = drm_gem_mmap_object_locked(dev, byte_offset, nbytes, prot,
70 1.3.4.2 yamt uobjp, uoffsetp);
71 1.3.4.2 yamt mutex_unlock(&dev->struct_mutex);
72 1.3.4.2 yamt
73 1.3.4.2 yamt return ret;
74 1.3.4.2 yamt }
75 1.3.4.2 yamt
76 1.3.4.2 yamt static int
77 1.3.4.2 yamt drm_gem_mmap_object_locked(struct drm_device *dev, off_t byte_offset,
78 1.3.4.2 yamt size_t nbytes, int prot __unused, struct uvm_object **uobjp,
79 1.3.4.2 yamt voff_t *uoffsetp)
80 1.3.4.2 yamt {
81 1.3.4.2 yamt struct drm_gem_mm *const mm = dev->mm_private;
82 1.3.4.2 yamt const off_t page_offset = (byte_offset >> PAGE_SHIFT);
83 1.3.4.2 yamt struct drm_hash_item *hash;
84 1.3.4.2 yamt
85 1.3.4.2 yamt KASSERT(mutex_is_locked(&dev->struct_mutex));
86 1.3.4.2 yamt KASSERT(drm_core_check_feature(dev, DRIVER_GEM));
87 1.3.4.2 yamt KASSERT(dev->driver->gem_uvm_ops != NULL);
88 1.3.4.2 yamt KASSERT(prot == (prot & (PROT_READ | PROT_WRITE)));
89 1.3.4.2 yamt KASSERT(byte_offset == (byte_offset & ~(PAGE_SIZE-1)));
90 1.3.4.2 yamt
91 1.3.4.2 yamt if (drm_ht_find_item(&mm->offset_hash, page_offset, &hash) != 0) {
92 1.3.4.2 yamt /* Fall back to vanilla device mappings. */
93 1.3.4.2 yamt *uobjp = NULL;
94 1.3.4.2 yamt *uoffsetp = (voff_t)-1;
95 1.3.4.2 yamt return 0;
96 1.3.4.2 yamt }
97 1.3.4.2 yamt
98 1.3.4.2 yamt struct drm_local_map *const map = drm_hash_entry(hash,
99 1.3.4.2 yamt struct drm_map_list, hash)->map;
100 1.3.4.2 yamt
101 1.3.4.2 yamt if (map == NULL) /* XXX How can this happen? */
102 1.3.4.2 yamt return -EINVAL;
103 1.3.4.2 yamt if (map->size < nbytes)
104 1.3.4.2 yamt return -EOVERFLOW;
105 1.3.4.2 yamt
106 1.3.4.2 yamt struct drm_gem_object *const obj = map->handle;
107 1.3.4.2 yamt KASSERT(obj->dev == dev);
108 1.3.4.2 yamt
109 1.3.4.2 yamt /* Success! */
110 1.3.4.2 yamt drm_gem_object_reference(obj);
111 1.3.4.2 yamt *uobjp = &obj->gemo_uvmobj;
112 1.3.4.2 yamt *uoffsetp = 0;
113 1.3.4.2 yamt return 0;
114 1.3.4.2 yamt }
115