1 /* 2 * Copyright © 2014-2016 Intel Corporation 3 * 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: 10 * 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 13 * Software. 14 * 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 21 * IN THE SOFTWARE. 22 * 23 */ 24 25 #include <drm/drmP.h> 26 #include <drm/i915_drm.h> 27 #include "i915_drv.h" 28 29 #define QUIET (__GFP_NORETRY | __GFP_NOWARN) 30 31 /* convert swiotlb segment size into sensible units (pages)! */ 32 #define IO_TLB_SEGPAGES (IO_TLB_SEGSIZE << IO_TLB_SHIFT >> PAGE_SHIFT) 33 34 static void internal_free_pages(struct sg_table *st) 35 { 36 struct scatterlist *sg; 37 38 for (sg = st->sgl; sg; sg = __sg_next(sg)) { 39 if (sg_page(sg)) 40 __free_pages(sg_page(sg), get_order(sg->length)); 41 } 42 43 sg_free_table(st); 44 kfree(st); 45 } 46 47 static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj) 48 { 49 struct drm_i915_private *i915 = to_i915(obj->base.dev); 50 struct sg_table *st; 51 struct scatterlist *sg; 52 unsigned int sg_page_sizes; 53 unsigned int npages; 54 int max_order; 55 gfp_t gfp; 56 57 max_order = MAX_ORDER; 58 #ifdef CONFIG_SWIOTLB 59 if (swiotlb_nr_tbl()) { 60 unsigned int max_segment; 61 62 max_segment = swiotlb_max_segment(); 63 if (max_segment) { 64 max_segment = max_t(unsigned int, max_segment, 65 PAGE_SIZE) >> PAGE_SHIFT; 66 max_order = min(max_order, ilog2(max_segment)); 67 } 68 } 69 #endif 70 71 gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_RECLAIMABLE; 72 if (IS_I965GM(i915) || IS_I965G(i915)) { 73 /* 965gm cannot relocate objects above 4GiB. */ 74 gfp &= ~__GFP_HIGHMEM; 75 gfp |= __GFP_DMA32; 76 } 77 78 create_st: 79 st = kmalloc(sizeof(*st), M_DRM, GFP_KERNEL); 80 if (!st) 81 return -ENOMEM; 82 83 npages = obj->base.size / PAGE_SIZE; 84 if (sg_alloc_table(st, npages, GFP_KERNEL)) { 85 kfree(st); 86 return -ENOMEM; 87 } 88 89 sg = st->sgl; 90 st->nents = 0; 91 sg_page_sizes = 0; 92 93 do { 94 int order = min(fls(npages) - 1, max_order); 95 struct page *page; 96 97 do { 98 page = alloc_pages(gfp | (order ? QUIET : 0), order); 99 if (page) 100 break; 101 if (!order--) 102 goto err; 103 104 /* Limit subsequent allocations as well */ 105 max_order = order; 106 } while (1); 107 108 sg_set_page(sg, page, PAGE_SIZE << order, 0); 109 sg_page_sizes |= PAGE_SIZE << order; 110 st->nents++; 111 112 npages -= 1 << order; 113 if (!npages) { 114 sg_mark_end(sg); 115 break; 116 } 117 118 sg = __sg_next(sg); 119 } while (1); 120 121 if (i915_gem_gtt_prepare_pages(obj, st)) { 122 /* Failed to dma-map try again with single page sg segments */ 123 if (get_order(st->sgl->length)) { 124 internal_free_pages(st); 125 max_order = 0; 126 goto create_st; 127 } 128 goto err; 129 } 130 131 /* Mark the pages as dontneed whilst they are still pinned. As soon 132 * as they are unpinned they are allowed to be reaped by the shrinker, 133 * and the caller is expected to repopulate - the contents of this 134 * object are only valid whilst active and pinned. 135 */ 136 obj->mm.madv = I915_MADV_DONTNEED; 137 138 __i915_gem_object_set_pages(obj, st, sg_page_sizes); 139 140 return 0; 141 142 err: 143 sg_set_page(sg, NULL, 0, 0); 144 sg_mark_end(sg); 145 internal_free_pages(st); 146 147 return -ENOMEM; 148 } 149 150 static void i915_gem_object_put_pages_internal(struct drm_i915_gem_object *obj, 151 struct sg_table *pages) 152 { 153 i915_gem_gtt_finish_pages(obj, pages); 154 internal_free_pages(pages); 155 156 obj->mm.dirty = false; 157 obj->mm.madv = I915_MADV_WILLNEED; 158 } 159 160 static const struct drm_i915_gem_object_ops i915_gem_object_internal_ops = { 161 .flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE | 162 I915_GEM_OBJECT_IS_SHRINKABLE, 163 .get_pages = i915_gem_object_get_pages_internal, 164 .put_pages = i915_gem_object_put_pages_internal, 165 }; 166 167 /** 168 * Creates a new object that wraps some internal memory for private use. 169 * This object is not backed by swappable storage, and as such its contents 170 * are volatile and only valid whilst pinned. If the object is reaped by the 171 * shrinker, its pages and data will be discarded. Equally, it is not a full 172 * GEM object and so not valid for access from userspace. This makes it useful 173 * for hardware interfaces like ringbuffers (which are pinned from the time 174 * the request is written to the time the hardware stops accessing it), but 175 * not for contexts (which need to be preserved when not active for later 176 * reuse). Note that it is not cleared upon allocation. 177 */ 178 struct drm_i915_gem_object * 179 i915_gem_object_create_internal(struct drm_i915_private *i915, 180 phys_addr_t size) 181 { 182 struct drm_i915_gem_object *obj; 183 unsigned int cache_level; 184 185 GEM_BUG_ON(!size); 186 GEM_BUG_ON(!IS_ALIGNED(size, PAGE_SIZE)); 187 188 if (overflows_type(size, obj->base.size)) 189 return ERR_PTR(-E2BIG); 190 191 obj = i915_gem_object_alloc(i915); 192 if (!obj) 193 return ERR_PTR(-ENOMEM); 194 195 drm_gem_private_object_init(&i915->drm, &obj->base, size); 196 i915_gem_object_init(obj, &i915_gem_object_internal_ops); 197 198 obj->base.read_domains = I915_GEM_DOMAIN_CPU; 199 obj->base.write_domain = I915_GEM_DOMAIN_CPU; 200 201 cache_level = HAS_LLC(i915) ? I915_CACHE_LLC : I915_CACHE_NONE; 202 i915_gem_object_set_cache_coherency(obj, cache_level); 203 204 return obj; 205 } 206