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