1 /*
2 * SPDX-License-Identifier: MIT
3 *
4 * Copyright © 2016 Intel Corporation
5 */
6
7 #include "i915_scatterlist.h"
8
9 #include "huge_gem_object.h"
10
huge_free_pages(struct drm_i915_gem_object * obj,struct sg_table * pages)11 static void huge_free_pages(struct drm_i915_gem_object *obj,
12 struct sg_table *pages)
13 {
14 unsigned long nreal = obj->scratch / PAGE_SIZE;
15 struct sgt_iter sgt_iter;
16 struct page *page;
17
18 for_each_sgt_page(page, sgt_iter, pages) {
19 __free_page(page);
20 if (!--nreal)
21 break;
22 }
23
24 sg_free_table(pages);
25 kfree(pages);
26 }
27
huge_get_pages(struct drm_i915_gem_object * obj)28 static int huge_get_pages(struct drm_i915_gem_object *obj)
29 {
30 #define GFP (GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY)
31 const unsigned long nreal = obj->scratch / PAGE_SIZE;
32 const unsigned long npages = obj->base.size / PAGE_SIZE;
33 struct scatterlist *sg, *src, *end;
34 struct sg_table *pages;
35 unsigned long n;
36
37 pages = kmalloc(sizeof(*pages), GFP);
38 if (!pages)
39 return -ENOMEM;
40
41 if (sg_alloc_table(pages, npages, GFP)) {
42 kfree(pages);
43 return -ENOMEM;
44 }
45
46 sg = pages->sgl;
47 for (n = 0; n < nreal; n++) {
48 struct page *page;
49
50 page = alloc_page(GFP | __GFP_HIGHMEM);
51 if (!page) {
52 sg_mark_end(sg);
53 goto err;
54 }
55
56 sg_set_page(sg, page, PAGE_SIZE, 0);
57 sg = __sg_next(sg);
58 }
59 if (nreal < npages) {
60 for (end = sg, src = pages->sgl; sg; sg = __sg_next(sg)) {
61 sg_set_page(sg, sg_page(src), PAGE_SIZE, 0);
62 src = __sg_next(src);
63 if (src == end)
64 src = pages->sgl;
65 }
66 }
67
68 if (i915_gem_gtt_prepare_pages(obj, pages))
69 goto err;
70
71 __i915_gem_object_set_pages(obj, pages, PAGE_SIZE);
72
73 return 0;
74
75 err:
76 huge_free_pages(obj, pages);
77 return -ENOMEM;
78 #undef GFP
79 }
80
huge_put_pages(struct drm_i915_gem_object * obj,struct sg_table * pages)81 static void huge_put_pages(struct drm_i915_gem_object *obj,
82 struct sg_table *pages)
83 {
84 i915_gem_gtt_finish_pages(obj, pages);
85 huge_free_pages(obj, pages);
86
87 obj->mm.dirty = false;
88 }
89
90 static const struct drm_i915_gem_object_ops huge_ops = {
91 .name = "huge-gem",
92 .flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE,
93 .get_pages = huge_get_pages,
94 .put_pages = huge_put_pages,
95 };
96
97 struct drm_i915_gem_object *
huge_gem_object(struct drm_i915_private * i915,phys_addr_t phys_size,dma_addr_t dma_size)98 huge_gem_object(struct drm_i915_private *i915,
99 phys_addr_t phys_size,
100 dma_addr_t dma_size)
101 {
102 static struct lock_class_key lock_class;
103 struct drm_i915_gem_object *obj;
104 unsigned int cache_level;
105
106 GEM_BUG_ON(!phys_size || phys_size > dma_size);
107 GEM_BUG_ON(!IS_ALIGNED(phys_size, PAGE_SIZE));
108 GEM_BUG_ON(!IS_ALIGNED(dma_size, I915_GTT_PAGE_SIZE));
109
110 if (overflows_type(dma_size, obj->base.size))
111 return ERR_PTR(-E2BIG);
112
113 obj = i915_gem_object_alloc();
114 if (!obj)
115 return ERR_PTR(-ENOMEM);
116
117 drm_gem_private_object_init(&i915->drm, &obj->base, dma_size);
118 i915_gem_object_init(obj, &huge_ops, &lock_class);
119
120 obj->read_domains = I915_GEM_DOMAIN_CPU;
121 obj->write_domain = I915_GEM_DOMAIN_CPU;
122 cache_level = HAS_LLC(i915) ? I915_CACHE_LLC : I915_CACHE_NONE;
123 i915_gem_object_set_cache_coherency(obj, cache_level);
124 obj->scratch = phys_size;
125
126 return obj;
127 }
128