2 * Copyright © 2014-2016 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
25 #include <drm/i915_drm.h>
28 #define QUIET (__GFP_NORETRY | __GFP_NOWARN)
29 #define MAYFAIL (__GFP_RETRY_MAYFAIL | __GFP_NOWARN)
31 static void internal_free_pages(struct sg_table *st)
33 struct scatterlist *sg;
35 for (sg = st->sgl; sg; sg = __sg_next(sg)) {
37 __free_pages(sg_page(sg), get_order(sg->length));
44 static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj)
46 struct drm_i915_private *i915 = to_i915(obj->base.dev);
48 struct scatterlist *sg;
49 unsigned int sg_page_sizes;
54 max_order = MAX_ORDER;
56 if (swiotlb_nr_tbl()) {
57 unsigned int max_segment;
59 max_segment = swiotlb_max_segment();
61 max_segment = max_t(unsigned int, max_segment,
62 PAGE_SIZE) >> PAGE_SHIFT;
63 max_order = min(max_order, ilog2(max_segment));
68 gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_RECLAIMABLE;
69 if (IS_I965GM(i915) || IS_I965G(i915)) {
70 /* 965gm cannot relocate objects above 4GiB. */
71 gfp &= ~__GFP_HIGHMEM;
76 st = kmalloc(sizeof(*st), GFP_KERNEL);
80 npages = obj->base.size / PAGE_SIZE;
81 if (sg_alloc_table(st, npages, GFP_KERNEL)) {
91 int order = min(fls(npages) - 1, max_order);
95 page = alloc_pages(gfp | (order ? QUIET : MAYFAIL),
102 /* Limit subsequent allocations as well */
106 sg_set_page(sg, page, PAGE_SIZE << order, 0);
107 sg_page_sizes |= PAGE_SIZE << order;
110 npages -= 1 << order;
119 if (i915_gem_gtt_prepare_pages(obj, st)) {
120 /* Failed to dma-map try again with single page sg segments */
121 if (get_order(st->sgl->length)) {
122 internal_free_pages(st);
129 /* Mark the pages as dontneed whilst they are still pinned. As soon
130 * as they are unpinned they are allowed to be reaped by the shrinker,
131 * and the caller is expected to repopulate - the contents of this
132 * object are only valid whilst active and pinned.
134 obj->mm.madv = I915_MADV_DONTNEED;
136 __i915_gem_object_set_pages(obj, st, sg_page_sizes);
141 sg_set_page(sg, NULL, 0, 0);
143 internal_free_pages(st);
148 static void i915_gem_object_put_pages_internal(struct drm_i915_gem_object *obj,
149 struct sg_table *pages)
151 i915_gem_gtt_finish_pages(obj, pages);
152 internal_free_pages(pages);
154 obj->mm.dirty = false;
155 obj->mm.madv = I915_MADV_WILLNEED;
158 static const struct drm_i915_gem_object_ops i915_gem_object_internal_ops = {
159 .flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE |
160 I915_GEM_OBJECT_IS_SHRINKABLE,
161 .get_pages = i915_gem_object_get_pages_internal,
162 .put_pages = i915_gem_object_put_pages_internal,
166 * i915_gem_object_create_internal: create an object with volatile pages
167 * @i915: the i915 device
168 * @size: the size in bytes of backing storage to allocate for the object
170 * Creates a new object that wraps some internal memory for private use.
171 * This object is not backed by swappable storage, and as such its contents
172 * are volatile and only valid whilst pinned. If the object is reaped by the
173 * shrinker, its pages and data will be discarded. Equally, it is not a full
174 * GEM object and so not valid for access from userspace. This makes it useful
175 * for hardware interfaces like ringbuffers (which are pinned from the time
176 * the request is written to the time the hardware stops accessing it), but
177 * not for contexts (which need to be preserved when not active for later
178 * reuse). Note that it is not cleared upon allocation.
180 struct drm_i915_gem_object *
181 i915_gem_object_create_internal(struct drm_i915_private *i915,
184 struct drm_i915_gem_object *obj;
185 unsigned int cache_level;
188 GEM_BUG_ON(!IS_ALIGNED(size, PAGE_SIZE));
190 if (overflows_type(size, obj->base.size))
191 return ERR_PTR(-E2BIG);
193 obj = i915_gem_object_alloc();
195 return ERR_PTR(-ENOMEM);
197 drm_gem_private_object_init(&i915->drm, &obj->base, size);
198 i915_gem_object_init(obj, &i915_gem_object_internal_ops);
200 obj->read_domains = I915_GEM_DOMAIN_CPU;
201 obj->write_domain = I915_GEM_DOMAIN_CPU;
203 cache_level = HAS_LLC(i915) ? I915_CACHE_LLC : I915_CACHE_NONE;
204 i915_gem_object_set_cache_coherency(obj, cache_level);