/* * SPDX-License-Identifier: MIT * * Copyright 2012 Red Hat Inc */ #include #include #include #include #include #include "gem/i915_gem_dmabuf.h" #include "i915_drv.h" #include "i915_gem_object.h" #include "i915_scatterlist.h" MODULE_IMPORT_NS(DMA_BUF); I915_SELFTEST_DECLARE(static bool force_different_devices;) static struct drm_i915_gem_object *dma_buf_to_obj(struct dma_buf *buf) { return to_intel_bo(buf->priv); } #ifdef notyet static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attach, enum dma_data_direction dir) { struct drm_i915_gem_object *obj = dma_buf_to_obj(attach->dmabuf); struct sg_table *sgt; struct scatterlist *src, *dst; int ret, i; /* * Make a copy of the object's sgt, so that we can make an independent * mapping */ sgt = kmalloc(sizeof(*sgt), GFP_KERNEL); if (!sgt) { ret = -ENOMEM; goto err; } ret = sg_alloc_table(sgt, obj->mm.pages->orig_nents, GFP_KERNEL); if (ret) goto err_free; dst = sgt->sgl; for_each_sg(obj->mm.pages->sgl, src, obj->mm.pages->orig_nents, i) { sg_set_page(dst, sg_page(src), src->length, 0); dst = sg_next(dst); } ret = dma_map_sgtable(attach->dev, sgt, dir, DMA_ATTR_SKIP_CPU_SYNC); if (ret) goto err_free_sg; return sgt; err_free_sg: sg_free_table(sgt); err_free: kfree(sgt); err: return ERR_PTR(ret); } static int i915_gem_dmabuf_vmap(struct dma_buf *dma_buf, struct iosys_map *map) { struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf); void *vaddr; vaddr = i915_gem_object_pin_map(obj, I915_MAP_WB); if (IS_ERR(vaddr)) return PTR_ERR(vaddr); iosys_map_set_vaddr(map, vaddr); return 0; } static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, struct iosys_map *map) { struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf); i915_gem_object_flush_map(obj); i915_gem_object_unpin_map(obj); } static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma) { struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf); struct drm_i915_private *i915 = to_i915(obj->base.dev); int ret; if (obj->base.size < vma->vm_end - vma->vm_start) return -EINVAL; if (HAS_LMEM(i915)) return drm_gem_prime_mmap(&obj->base, vma); if (!obj->base.filp) return -ENODEV; ret = call_mmap(obj->base.filp, vma); if (ret) return ret; vma_set_file(vma, obj->base.filp); return 0; } static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction) { struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf); bool write = (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE); struct i915_gem_ww_ctx ww; int err; i915_gem_ww_ctx_init(&ww, true); retry: err = i915_gem_object_lock(obj, &ww); if (!err) err = i915_gem_object_pin_pages(obj); if (!err) { err = i915_gem_object_set_to_cpu_domain(obj, write); i915_gem_object_unpin_pages(obj); } if (err == -EDEADLK) { err = i915_gem_ww_ctx_backoff(&ww); if (!err) goto retry; } i915_gem_ww_ctx_fini(&ww); return err; } static int i915_gem_end_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction) { struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf); struct i915_gem_ww_ctx ww; int err; i915_gem_ww_ctx_init(&ww, true); retry: err = i915_gem_object_lock(obj, &ww); if (!err) err = i915_gem_object_pin_pages(obj); if (!err) { err = i915_gem_object_set_to_gtt_domain(obj, false); i915_gem_object_unpin_pages(obj); } if (err == -EDEADLK) { err = i915_gem_ww_ctx_backoff(&ww); if (!err) goto retry; } i915_gem_ww_ctx_fini(&ww); return err; } static int i915_gem_dmabuf_attach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) { struct drm_i915_gem_object *obj = dma_buf_to_obj(dmabuf); struct i915_gem_ww_ctx ww; int err; if (!i915_gem_object_can_migrate(obj, INTEL_REGION_SMEM)) return -EOPNOTSUPP; for_i915_gem_ww(&ww, err, true) { err = i915_gem_object_lock(obj, &ww); if (err) continue; err = i915_gem_object_migrate(obj, &ww, INTEL_REGION_SMEM); if (err) continue; err = i915_gem_object_wait_migration(obj, 0); if (err) continue; err = i915_gem_object_pin_pages(obj); } return err; } static void i915_gem_dmabuf_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attach) { struct drm_i915_gem_object *obj = dma_buf_to_obj(dmabuf); i915_gem_object_unpin_pages(obj); } #endif /* notyet */ static const struct dma_buf_ops i915_dmabuf_ops = { #ifdef notyet .attach = i915_gem_dmabuf_attach, .detach = i915_gem_dmabuf_detach, .map_dma_buf = i915_gem_map_dma_buf, .unmap_dma_buf = drm_gem_unmap_dma_buf, #endif .release = drm_gem_dmabuf_release, #ifdef notyet .mmap = i915_gem_dmabuf_mmap, .vmap = i915_gem_dmabuf_vmap, .vunmap = i915_gem_dmabuf_vunmap, .begin_cpu_access = i915_gem_begin_cpu_access, .end_cpu_access = i915_gem_end_cpu_access, #endif }; struct dma_buf *i915_gem_prime_export(struct drm_gem_object *gem_obj, int flags) { struct drm_i915_gem_object *obj = to_intel_bo(gem_obj); DEFINE_DMA_BUF_EXPORT_INFO(exp_info); exp_info.ops = &i915_dmabuf_ops; exp_info.size = gem_obj->size; exp_info.flags = flags; exp_info.priv = gem_obj; exp_info.resv = obj->base.resv; if (obj->ops->dmabuf_export) { int ret = obj->ops->dmabuf_export(obj); if (ret) return ERR_PTR(ret); } return drm_gem_dmabuf_export(gem_obj->dev, &exp_info); } #ifdef notyet static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj) { struct drm_i915_private *i915 = to_i915(obj->base.dev); struct sg_table *sgt; assert_object_held(obj); sgt = dma_buf_map_attachment(obj->base.import_attach, DMA_BIDIRECTIONAL); if (IS_ERR(sgt)) return PTR_ERR(sgt); /* * DG1 is special here since it still snoops transactions even with * CACHE_NONE. This is not the case with other HAS_SNOOP platforms. We * might need to revisit this as we add new discrete platforms. * * XXX: Consider doing a vmap flush or something, where possible. * Currently we just do a heavy handed wbinvd_on_all_cpus() here since * the underlying sg_table might not even point to struct pages, so we * can't just call drm_clflush_sg or similar, like we do elsewhere in * the driver. */ if (i915_gem_object_can_bypass_llc(obj) || (!HAS_LLC(i915) && !IS_DG1(i915))) wbinvd_on_all_cpus(); __i915_gem_object_set_pages(obj, sgt); return 0; } static void i915_gem_object_put_pages_dmabuf(struct drm_i915_gem_object *obj, struct sg_table *sgt) { dma_buf_unmap_attachment(obj->base.import_attach, sgt, DMA_BIDIRECTIONAL); } static const struct drm_i915_gem_object_ops i915_gem_object_dmabuf_ops = { .name = "i915_gem_object_dmabuf", .get_pages = i915_gem_object_get_pages_dmabuf, .put_pages = i915_gem_object_put_pages_dmabuf, }; #endif /* notyet */ struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev, struct dma_buf *dma_buf) { static struct lock_class_key lock_class; struct dma_buf_attachment *attach; struct drm_i915_gem_object *obj; int ret; /* is this one of own objects? */ if (dma_buf->ops == &i915_dmabuf_ops) { obj = dma_buf_to_obj(dma_buf); /* is it from our device? */ if (obj->base.dev == dev && !I915_SELFTEST_ONLY(force_different_devices)) { /* * Importing dmabuf exported from out own gem increases * refcount on gem itself instead of f_count of dmabuf. */ return &i915_gem_object_get(obj)->base; } } if (i915_gem_object_size_2big(dma_buf->size)) return ERR_PTR(-E2BIG); /* need to attach */ attach = dma_buf_attach(dma_buf, dev->dev); if (IS_ERR(attach)) return ERR_CAST(attach); #ifdef notyet get_dma_buf(dma_buf); obj = i915_gem_object_alloc(); if (!obj) { ret = -ENOMEM; goto fail_detach; } drm_gem_private_object_init(dev, &obj->base, dma_buf->size); i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops, &lock_class, I915_BO_ALLOC_USER); obj->base.import_attach = attach; obj->base.resv = dma_buf->resv; /* We use GTT as shorthand for a coherent domain, one that is * neither in the GPU cache nor in the CPU cache, where all * writes are immediately visible in memory. (That's not strictly * true, but it's close! There are internal buffers such as the * write-combined buffer or a delay through the chipset for GTT * writes that do require us to treat GTT as a separate cache domain.) */ obj->read_domains = I915_GEM_DOMAIN_GTT; obj->write_domain = 0; return &obj->base; fail_detach: dma_buf_detach(dma_buf, attach); dma_buf_put(dma_buf); return ERR_PTR(ret); #else ret = 0; panic(__func__); #endif } #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) #include "selftests/mock_dmabuf.c" #include "selftests/i915_gem_dmabuf.c" #endif