diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gem/i915_gem_internal.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gem/i915_gem_internal.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c b/drivers/gpu/drm/i915/gem/i915_gem_internal.c new file mode 100644 index 000000000000..0c41e04ab8fa --- /dev/null +++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c @@ -0,0 +1,198 @@ +/* + * SPDX-License-Identifier: MIT + * + * Copyright © 2014-2016 Intel Corporation + */ + +#include <linux/scatterlist.h> +#include <linux/slab.h> +#include <linux/swiotlb.h> + +#include <drm/i915_drm.h> + +#include "i915_drv.h" +#include "i915_gem.h" +#include "i915_gem_object.h" +#include "i915_scatterlist.h" +#include "i915_utils.h" + +#define QUIET (__GFP_NORETRY | __GFP_NOWARN) +#define MAYFAIL (__GFP_RETRY_MAYFAIL | __GFP_NOWARN) + +static void internal_free_pages(struct sg_table *st) +{ + struct scatterlist *sg; + + for (sg = st->sgl; sg; sg = __sg_next(sg)) { + if (sg_page(sg)) + __free_pages(sg_page(sg), get_order(sg->length)); + } + + sg_free_table(st); + kfree(st); +} + +static int i915_gem_object_get_pages_internal(struct drm_i915_gem_object *obj) +{ + struct drm_i915_private *i915 = to_i915(obj->base.dev); + struct sg_table *st; + struct scatterlist *sg; + unsigned int sg_page_sizes; + unsigned int npages; + int max_order; + gfp_t gfp; + + max_order = MAX_ORDER; +#ifdef CONFIG_SWIOTLB + if (swiotlb_nr_tbl()) { + unsigned int max_segment; + + max_segment = swiotlb_max_segment(); + if (max_segment) { + max_segment = max_t(unsigned int, max_segment, + PAGE_SIZE) >> PAGE_SHIFT; + max_order = min(max_order, ilog2(max_segment)); + } + } +#endif + + gfp = GFP_KERNEL | __GFP_HIGHMEM | __GFP_RECLAIMABLE; + if (IS_I965GM(i915) || IS_I965G(i915)) { + /* 965gm cannot relocate objects above 4GiB. */ + gfp &= ~__GFP_HIGHMEM; + gfp |= __GFP_DMA32; + } + +create_st: + st = kmalloc(sizeof(*st), GFP_KERNEL); + if (!st) + return -ENOMEM; + + npages = obj->base.size / PAGE_SIZE; + if (sg_alloc_table(st, npages, GFP_KERNEL)) { + kfree(st); + return -ENOMEM; + } + + sg = st->sgl; + st->nents = 0; + sg_page_sizes = 0; + + do { + int order = min(fls(npages) - 1, max_order); + struct page *page; + + do { + page = alloc_pages(gfp | (order ? QUIET : MAYFAIL), + order); + if (page) + break; + if (!order--) + goto err; + + /* Limit subsequent allocations as well */ + max_order = order; + } while (1); + + sg_set_page(sg, page, PAGE_SIZE << order, 0); + sg_page_sizes |= PAGE_SIZE << order; + st->nents++; + + npages -= 1 << order; + if (!npages) { + sg_mark_end(sg); + break; + } + + sg = __sg_next(sg); + } while (1); + + if (i915_gem_gtt_prepare_pages(obj, st)) { + /* Failed to dma-map try again with single page sg segments */ + if (get_order(st->sgl->length)) { + internal_free_pages(st); + max_order = 0; + goto create_st; + } + goto err; + } + + /* Mark the pages as dontneed whilst they are still pinned. As soon + * as they are unpinned they are allowed to be reaped by the shrinker, + * and the caller is expected to repopulate - the contents of this + * object are only valid whilst active and pinned. + */ + obj->mm.madv = I915_MADV_DONTNEED; + + __i915_gem_object_set_pages(obj, st, sg_page_sizes); + + return 0; + +err: + sg_set_page(sg, NULL, 0, 0); + sg_mark_end(sg); + internal_free_pages(st); + + return -ENOMEM; +} + +static void i915_gem_object_put_pages_internal(struct drm_i915_gem_object *obj, + struct sg_table *pages) +{ + i915_gem_gtt_finish_pages(obj, pages); + internal_free_pages(pages); + + obj->mm.dirty = false; + obj->mm.madv = I915_MADV_WILLNEED; +} + +static const struct drm_i915_gem_object_ops i915_gem_object_internal_ops = { + .flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE | + I915_GEM_OBJECT_IS_SHRINKABLE, + .get_pages = i915_gem_object_get_pages_internal, + .put_pages = i915_gem_object_put_pages_internal, +}; + +/** + * i915_gem_object_create_internal: create an object with volatile pages + * @i915: the i915 device + * @size: the size in bytes of backing storage to allocate for the object + * + * Creates a new object that wraps some internal memory for private use. + * This object is not backed by swappable storage, and as such its contents + * are volatile and only valid whilst pinned. If the object is reaped by the + * shrinker, its pages and data will be discarded. Equally, it is not a full + * GEM object and so not valid for access from userspace. This makes it useful + * for hardware interfaces like ringbuffers (which are pinned from the time + * the request is written to the time the hardware stops accessing it), but + * not for contexts (which need to be preserved when not active for later + * reuse). Note that it is not cleared upon allocation. + */ +struct drm_i915_gem_object * +i915_gem_object_create_internal(struct drm_i915_private *i915, + phys_addr_t size) +{ + struct drm_i915_gem_object *obj; + unsigned int cache_level; + + GEM_BUG_ON(!size); + GEM_BUG_ON(!IS_ALIGNED(size, PAGE_SIZE)); + + if (overflows_type(size, obj->base.size)) + return ERR_PTR(-E2BIG); + + obj = i915_gem_object_alloc(); + if (!obj) + return ERR_PTR(-ENOMEM); + + drm_gem_private_object_init(&i915->drm, &obj->base, size); + i915_gem_object_init(obj, &i915_gem_object_internal_ops); + + obj->read_domains = I915_GEM_DOMAIN_CPU; + obj->write_domain = I915_GEM_DOMAIN_CPU; + + cache_level = HAS_LLC(i915) ? I915_CACHE_LLC : I915_CACHE_NONE; + i915_gem_object_set_cache_coherency(obj, cache_level); + + return obj; +} |