// SPDX-License-Identifier: MIT /* * Copyright © 2021 Intel Corporation */ #include #include #include "i915_drv.h" #include "intel_memory_region.h" #include "intel_region_ttm.h" #include "gem/i915_gem_object.h" #include "gem/i915_gem_region.h" #include "gem/i915_gem_ttm.h" #include "gem/i915_gem_mman.h" #include "gt/intel_migrate.h" #include "gt/intel_engine_pm.h" #define I915_PL_LMEM0 TTM_PL_PRIV #define I915_PL_SYSTEM TTM_PL_SYSTEM #define I915_PL_STOLEN TTM_PL_VRAM #define I915_PL_GGTT TTM_PL_TT #define I915_TTM_PRIO_PURGE 0 #define I915_TTM_PRIO_NO_PAGES 1 #define I915_TTM_PRIO_HAS_PAGES 2 /* * Size of struct ttm_place vector in on-stack struct ttm_placement allocs */ #define I915_TTM_MAX_PLACEMENTS INTEL_REGION_UNKNOWN /** * struct i915_ttm_tt - TTM page vector with additional private information * @ttm: The base TTM page vector. * @dev: The struct device used for dma mapping and unmapping. * @cached_st: The cached scatter-gather table. * * Note that DMA may be going on right up to the point where the page- * vector is unpopulated in delayed destroy. Hence keep the * scatter-gather table mapped and cached up to that point. This is * different from the cached gem object io scatter-gather table which * doesn't have an associated dma mapping. */ struct i915_ttm_tt { struct ttm_tt ttm; struct device *dev; struct sg_table *cached_st; }; static const struct ttm_place sys_placement_flags = { .fpfn = 0, .lpfn = 0, .mem_type = I915_PL_SYSTEM, .flags = 0, }; static struct ttm_placement i915_sys_placement = { .num_placement = 1, .placement = &sys_placement_flags, .num_busy_placement = 1, .busy_placement = &sys_placement_flags, }; static int i915_ttm_err_to_gem(int err) { /* Fastpath */ if (likely(!err)) return 0; switch (err) { case -EBUSY: /* * TTM likes to convert -EDEADLK to -EBUSY, and wants us to * restart the operation, since we don't record the contending * lock. We use -EAGAIN to restart. */ return -EAGAIN; case -ENOSPC: /* * Memory type / region is full, and we can't evict. * Except possibly system, that returns -ENOMEM; */ return -ENXIO; default: break; } return err; } static bool gpu_binds_iomem(struct ttm_resource *mem) { return mem->mem_type != TTM_PL_SYSTEM; } static bool cpu_maps_iomem(struct ttm_resource *mem) { /* Once / if we support GGTT, this is also false for cached ttm_tts */ return mem->mem_type != TTM_PL_SYSTEM; } static enum i915_cache_level i915_ttm_cache_level(struct drm_i915_private *i915, struct ttm_resource *res, struct ttm_tt *ttm) { return ((HAS_LLC(i915) || HAS_SNOOP(i915)) && !gpu_binds_iomem(res) && ttm->caching == ttm_cached) ? I915_CACHE_LLC : I915_CACHE_NONE; } static void i915_ttm_adjust_lru(struct drm_i915_gem_object *obj); static enum ttm_caching i915_ttm_select_tt_caching(const struct drm_i915_gem_object *obj) { /* * Objects only allowed in system get cached cpu-mappings. * Other objects get WC mapping for now. Even if in system. */ if (obj->mm.region->type == INTEL_MEMORY_SYSTEM && obj->mm.n_placements <= 1) return ttm_cached; return ttm_write_combined; } static void i915_ttm_place_from_region(const struct intel_memory_region *mr, struct ttm_place *place, unsigned int flags) { memset(place, 0, sizeof(*place)); place->mem_type = intel_region_to_ttm_type(mr); if (flags & I915_BO_ALLOC_CONTIGUOUS) place->flags = TTM_PL_FLAG_CONTIGUOUS; } static void i915_ttm_placement_from_obj(const struct drm_i915_gem_object *obj, struct ttm_place *requested, struct ttm_place *busy, struct ttm_placement *placement) { unsigned int num_allowed = obj->mm.n_placements; unsigned int flags = obj->flags; unsigned int i; placement->num_placement = 1; i915_ttm_place_from_region(num_allowed ? obj->mm.placements[0] : obj->mm.region, requested, flags); /* Cache this on object? */ placement->num_busy_placement = num_allowed; for (i = 0; i < placement->num_busy_placement; ++i) i915_ttm_place_from_region(obj->mm.placements[i], busy + i, flags); if (num_allowed == 0) { *busy = *requested; placement->num_busy_placement = 1; } placement->placement = requested; placement->busy_placement = busy; } static struct ttm_tt *i915_ttm_tt_create(struct ttm_buffer_object *bo, uint32_t page_flags) { struct ttm_resource_manager *man = ttm_manager_type(bo->bdev, bo->resource->mem_type); struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); struct i915_ttm_tt *i915_tt; int ret; i915_tt = kzalloc(sizeof(*i915_tt), GFP_KERNEL); if (!i915_tt) return NULL; if (obj->flags & I915_BO_ALLOC_CPU_CLEAR && man->use_tt) page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC; ret = ttm_tt_init(&i915_tt->ttm, bo, page_flags, i915_ttm_select_tt_caching(obj)); if (ret) { kfree(i915_tt); return NULL; } i915_tt->dev = obj->base.dev->dev; return &i915_tt->ttm; } static void i915_ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm) { struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); if (i915_tt->cached_st) { dma_unmap_sgtable(i915_tt->dev, i915_tt->cached_st, DMA_BIDIRECTIONAL, 0); sg_free_table(i915_tt->cached_st); kfree(i915_tt->cached_st); i915_tt->cached_st = NULL; } ttm_pool_free(&bdev->pool, ttm); } static void i915_ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm) { struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); ttm_tt_destroy_common(bdev, ttm); ttm_tt_fini(ttm); kfree(i915_tt); } static bool i915_ttm_eviction_valuable(struct ttm_buffer_object *bo, const struct ttm_place *place) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); /* Will do for now. Our pinned objects are still on TTM's LRU lists */ return i915_gem_object_evictable(obj); } static void i915_ttm_evict_flags(struct ttm_buffer_object *bo, struct ttm_placement *placement) { *placement = i915_sys_placement; } static int i915_ttm_move_notify(struct ttm_buffer_object *bo) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); int ret; ret = i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE); if (ret) return ret; ret = __i915_gem_object_put_pages(obj); if (ret) return ret; return 0; } static void i915_ttm_free_cached_io_st(struct drm_i915_gem_object *obj) { struct radix_tree_iter iter; void __rcu **slot; if (!obj->ttm.cached_io_st) return; rcu_read_lock(); radix_tree_for_each_slot(slot, &obj->ttm.get_io_page.radix, &iter, 0) radix_tree_delete(&obj->ttm.get_io_page.radix, iter.index); rcu_read_unlock(); sg_free_table(obj->ttm.cached_io_st); kfree(obj->ttm.cached_io_st); obj->ttm.cached_io_st = NULL; } static void i915_ttm_adjust_domains_after_move(struct drm_i915_gem_object *obj) { struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); if (cpu_maps_iomem(bo->resource) || bo->ttm->caching != ttm_cached) { obj->write_domain = I915_GEM_DOMAIN_WC; obj->read_domains = I915_GEM_DOMAIN_WC; } else { obj->write_domain = I915_GEM_DOMAIN_CPU; obj->read_domains = I915_GEM_DOMAIN_CPU; } } static void i915_ttm_adjust_gem_after_move(struct drm_i915_gem_object *obj) { struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); unsigned int cache_level; unsigned int i; /* * If object was moved to an allowable region, update the object * region to consider it migrated. Note that if it's currently not * in an allowable region, it's evicted and we don't update the * object region. */ if (intel_region_to_ttm_type(obj->mm.region) != bo->resource->mem_type) { for (i = 0; i < obj->mm.n_placements; ++i) { struct intel_memory_region *mr = obj->mm.placements[i]; if (intel_region_to_ttm_type(mr) == bo->resource->mem_type && mr != obj->mm.region) { i915_gem_object_release_memory_region(obj); i915_gem_object_init_memory_region(obj, mr); break; } } } obj->mem_flags &= ~(I915_BO_FLAG_STRUCT_PAGE | I915_BO_FLAG_IOMEM); obj->mem_flags |= cpu_maps_iomem(bo->resource) ? I915_BO_FLAG_IOMEM : I915_BO_FLAG_STRUCT_PAGE; cache_level = i915_ttm_cache_level(to_i915(bo->base.dev), bo->resource, bo->ttm); i915_gem_object_set_cache_coherency(obj, cache_level); } static void i915_ttm_purge(struct drm_i915_gem_object *obj) { struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); struct ttm_operation_ctx ctx = { .interruptible = true, .no_wait_gpu = false, }; struct ttm_placement place = {}; int ret; if (obj->mm.madv == __I915_MADV_PURGED) return; /* TTM's purge interface. Note that we might be reentering. */ ret = ttm_bo_validate(bo, &place, &ctx); if (!ret) { obj->write_domain = 0; obj->read_domains = 0; i915_ttm_adjust_gem_after_move(obj); i915_ttm_free_cached_io_st(obj); obj->mm.madv = __I915_MADV_PURGED; } } static void i915_ttm_swap_notify(struct ttm_buffer_object *bo) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); int ret = i915_ttm_move_notify(bo); GEM_WARN_ON(ret); GEM_WARN_ON(obj->ttm.cached_io_st); if (!ret && obj->mm.madv != I915_MADV_WILLNEED) i915_ttm_purge(obj); } static void i915_ttm_delete_mem_notify(struct ttm_buffer_object *bo) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); if (likely(obj)) { /* This releases all gem object bindings to the backend. */ i915_ttm_free_cached_io_st(obj); __i915_gem_free_object(obj); } } static struct intel_memory_region * i915_ttm_region(struct ttm_device *bdev, int ttm_mem_type) { struct drm_i915_private *i915 = container_of(bdev, typeof(*i915), bdev); /* There's some room for optimization here... */ GEM_BUG_ON(ttm_mem_type != I915_PL_SYSTEM && ttm_mem_type < I915_PL_LMEM0); if (ttm_mem_type == I915_PL_SYSTEM) return intel_memory_region_lookup(i915, INTEL_MEMORY_SYSTEM, 0); return intel_memory_region_lookup(i915, INTEL_MEMORY_LOCAL, ttm_mem_type - I915_PL_LMEM0); } static struct sg_table *i915_ttm_tt_get_st(struct ttm_tt *ttm) { struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); struct sg_table *st; int ret; if (i915_tt->cached_st) return i915_tt->cached_st; st = kzalloc(sizeof(*st), GFP_KERNEL); if (!st) return ERR_PTR(-ENOMEM); ret = sg_alloc_table_from_pages_segment(st, ttm->pages, ttm->num_pages, 0, (unsigned long)ttm->num_pages << PAGE_SHIFT, i915_sg_segment_size(), GFP_KERNEL); if (ret) { kfree(st); return ERR_PTR(ret); } ret = dma_map_sgtable(i915_tt->dev, st, DMA_BIDIRECTIONAL, 0); if (ret) { sg_free_table(st); kfree(st); return ERR_PTR(ret); } i915_tt->cached_st = st; return st; } static struct sg_table * i915_ttm_resource_get_st(struct drm_i915_gem_object *obj, struct ttm_resource *res) { struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); if (!gpu_binds_iomem(res)) return i915_ttm_tt_get_st(bo->ttm); /* * If CPU mapping differs, we need to add the ttm_tt pages to * the resulting st. Might make sense for GGTT. */ GEM_WARN_ON(!cpu_maps_iomem(res)); return intel_region_ttm_resource_to_st(obj->mm.region, res); } static int i915_ttm_accel_move(struct ttm_buffer_object *bo, struct ttm_resource *dst_mem, struct sg_table *dst_st) { struct drm_i915_private *i915 = container_of(bo->bdev, typeof(*i915), bdev); struct ttm_resource_manager *src_man = ttm_manager_type(bo->bdev, bo->resource->mem_type); struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); struct sg_table *src_st; struct i915_request *rq; struct ttm_tt *ttm = bo->ttm; enum i915_cache_level src_level, dst_level; int ret; if (!i915->gt.migrate.context) return -EINVAL; dst_level = i915_ttm_cache_level(i915, dst_mem, ttm); if (!ttm || !ttm_tt_is_populated(ttm)) { if (bo->type == ttm_bo_type_kernel) return -EINVAL; if (ttm && !(ttm->page_flags & TTM_PAGE_FLAG_ZERO_ALLOC)) return 0; intel_engine_pm_get(i915->gt.migrate.context->engine); ret = intel_context_migrate_clear(i915->gt.migrate.context, NULL, dst_st->sgl, dst_level, gpu_binds_iomem(dst_mem), 0, &rq); if (!ret && rq) { i915_request_wait(rq, 0, MAX_SCHEDULE_TIMEOUT); i915_request_put(rq); } intel_engine_pm_put(i915->gt.migrate.context->engine); } else { src_st = src_man->use_tt ? i915_ttm_tt_get_st(ttm) : obj->ttm.cached_io_st; src_level = i915_ttm_cache_level(i915, bo->resource, ttm); intel_engine_pm_get(i915->gt.migrate.context->engine); ret = intel_context_migrate_copy(i915->gt.migrate.context, NULL, src_st->sgl, src_level, gpu_binds_iomem(bo->resource), dst_st->sgl, dst_level, gpu_binds_iomem(dst_mem), &rq); if (!ret && rq) { i915_request_wait(rq, 0, MAX_SCHEDULE_TIMEOUT); i915_request_put(rq); } intel_engine_pm_put(i915->gt.migrate.context->engine); } return ret; } static int i915_ttm_move(struct ttm_buffer_object *bo, bool evict, struct ttm_operation_ctx *ctx, struct ttm_resource *dst_mem, struct ttm_place *hop) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); struct ttm_resource_manager *dst_man = ttm_manager_type(bo->bdev, dst_mem->mem_type); struct intel_memory_region *dst_reg, *src_reg; union { struct ttm_kmap_iter_tt tt; struct ttm_kmap_iter_iomap io; } _dst_iter, _src_iter; struct ttm_kmap_iter *dst_iter, *src_iter; struct sg_table *dst_st; int ret; dst_reg = i915_ttm_region(bo->bdev, dst_mem->mem_type); src_reg = i915_ttm_region(bo->bdev, bo->resource->mem_type); GEM_BUG_ON(!dst_reg || !src_reg); /* Sync for now. We could do the actual copy async. */ ret = ttm_bo_wait_ctx(bo, ctx); if (ret) return ret; ret = i915_ttm_move_notify(bo); if (ret) return ret; if (obj->mm.madv != I915_MADV_WILLNEED) { i915_ttm_purge(obj); ttm_resource_free(bo, &dst_mem); return 0; } /* Populate ttm with pages if needed. Typically system memory. */ if (bo->ttm && (dst_man->use_tt || (bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED))) { ret = ttm_tt_populate(bo->bdev, bo->ttm, ctx); if (ret) return ret; } dst_st = i915_ttm_resource_get_st(obj, dst_mem); if (IS_ERR(dst_st)) return PTR_ERR(dst_st); ret = i915_ttm_accel_move(bo, dst_mem, dst_st); if (ret) { /* If we start mapping GGTT, we can no longer use man::use_tt here. */ dst_iter = !cpu_maps_iomem(dst_mem) ? ttm_kmap_iter_tt_init(&_dst_iter.tt, bo->ttm) : ttm_kmap_iter_iomap_init(&_dst_iter.io, &dst_reg->iomap, dst_st, dst_reg->region.start); src_iter = !cpu_maps_iomem(bo->resource) ? ttm_kmap_iter_tt_init(&_src_iter.tt, bo->ttm) : ttm_kmap_iter_iomap_init(&_src_iter.io, &src_reg->iomap, obj->ttm.cached_io_st, src_reg->region.start); ttm_move_memcpy(bo, dst_mem->num_pages, dst_iter, src_iter); } /* Below dst_mem becomes bo->resource. */ ttm_bo_move_sync_cleanup(bo, dst_mem); i915_ttm_adjust_domains_after_move(obj); i915_ttm_free_cached_io_st(obj); if (gpu_binds_iomem(dst_mem) || cpu_maps_iomem(dst_mem)) { obj->ttm.cached_io_st = dst_st; obj->ttm.get_io_page.sg_pos = dst_st->sgl; obj->ttm.get_io_page.sg_idx = 0; } i915_ttm_adjust_gem_after_move(obj); return 0; } static int i915_ttm_io_mem_reserve(struct ttm_device *bdev, struct ttm_resource *mem) { if (!cpu_maps_iomem(mem)) return 0; mem->bus.caching = ttm_write_combined; mem->bus.is_iomem = true; return 0; } static unsigned long i915_ttm_io_mem_pfn(struct ttm_buffer_object *bo, unsigned long page_offset) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); unsigned long base = obj->mm.region->iomap.base - obj->mm.region->region.start; struct scatterlist *sg; unsigned int ofs; GEM_WARN_ON(bo->ttm); sg = __i915_gem_object_get_sg(obj, &obj->ttm.get_io_page, page_offset, &ofs, true); return ((base + sg_dma_address(sg)) >> PAGE_SHIFT) + ofs; } static struct ttm_device_funcs i915_ttm_bo_driver = { .ttm_tt_create = i915_ttm_tt_create, .ttm_tt_unpopulate = i915_ttm_tt_unpopulate, .ttm_tt_destroy = i915_ttm_tt_destroy, .eviction_valuable = i915_ttm_eviction_valuable, .evict_flags = i915_ttm_evict_flags, .move = i915_ttm_move, .swap_notify = i915_ttm_swap_notify, .delete_mem_notify = i915_ttm_delete_mem_notify, .io_mem_reserve = i915_ttm_io_mem_reserve, .io_mem_pfn = i915_ttm_io_mem_pfn, }; /** * i915_ttm_driver - Return a pointer to the TTM device funcs * * Return: Pointer to statically allocated TTM device funcs. */ struct ttm_device_funcs *i915_ttm_driver(void) { return &i915_ttm_bo_driver; } static int __i915_ttm_get_pages(struct drm_i915_gem_object *obj, struct ttm_placement *placement) { struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); struct ttm_operation_ctx ctx = { .interruptible = true, .no_wait_gpu = false, }; struct sg_table *st; int real_num_busy; int ret; /* First try only the requested placement. No eviction. */ real_num_busy = fetch_and_zero(&placement->num_busy_placement); ret = ttm_bo_validate(bo, placement, &ctx); if (ret) { ret = i915_ttm_err_to_gem(ret); /* * Anything that wants to restart the operation gets to * do that. */ if (ret == -EDEADLK || ret == -EINTR || ret == -ERESTARTSYS || ret == -EAGAIN) return ret; /* * If the initial attempt fails, allow all accepted placements, * evicting if necessary. */ placement->num_busy_placement = real_num_busy; ret = ttm_bo_validate(bo, placement, &ctx); if (ret) return i915_ttm_err_to_gem(ret); } i915_ttm_adjust_lru(obj); if (bo->ttm && !ttm_tt_is_populated(bo->ttm)) { ret = ttm_tt_populate(bo->bdev, bo->ttm, &ctx); if (ret) return ret; i915_ttm_adjust_domains_after_move(obj); i915_ttm_adjust_gem_after_move(obj); } if (!i915_gem_object_has_pages(obj)) { /* Object either has a page vector or is an iomem object */ st = bo->ttm ? i915_ttm_tt_get_st(bo->ttm) : obj->ttm.cached_io_st; if (IS_ERR(st)) return PTR_ERR(st); __i915_gem_object_set_pages(obj, st, i915_sg_dma_sizes(st->sgl)); } return ret; } static int i915_ttm_get_pages(struct drm_i915_gem_object *obj) { struct ttm_place requested, busy[I915_TTM_MAX_PLACEMENTS]; struct ttm_placement placement; GEM_BUG_ON(obj->mm.n_placements > I915_TTM_MAX_PLACEMENTS); /* Move to the requested placement. */ i915_ttm_placement_from_obj(obj, &requested, busy, &placement); return __i915_ttm_get_pages(obj, &placement); } /** * DOC: Migration vs eviction * * GEM migration may not be the same as TTM migration / eviction. If * the TTM core decides to evict an object it may be evicted to a * TTM memory type that is not in the object's allowable GEM regions, or * in fact theoretically to a TTM memory type that doesn't correspond to * a GEM memory region. In that case the object's GEM region is not * updated, and the data is migrated back to the GEM region at * get_pages time. TTM may however set up CPU ptes to the object even * when it is evicted. * Gem forced migration using the i915_ttm_migrate() op, is allowed even * to regions that are not in the object's list of allowable placements. */ static int i915_ttm_migrate(struct drm_i915_gem_object *obj, struct intel_memory_region *mr) { struct ttm_place requested; struct ttm_placement placement; int ret; i915_ttm_place_from_region(mr, &requested, obj->flags); placement.num_placement = 1; placement.num_busy_placement = 1; placement.placement = &requested; placement.busy_placement = &requested; ret = __i915_ttm_get_pages(obj, &placement); if (ret) return ret; /* * Reinitialize the region bindings. This is primarily * required for objects where the new region is not in * its allowable placements. */ if (obj->mm.region != mr) { i915_gem_object_release_memory_region(obj); i915_gem_object_init_memory_region(obj, mr); } return 0; } static void i915_ttm_put_pages(struct drm_i915_gem_object *obj, struct sg_table *st) { /* * We're currently not called from a shrinker, so put_pages() * typically means the object is about to destroyed, or called * from move_notify(). So just avoid doing much for now. * If the object is not destroyed next, The TTM eviction logic * and shrinkers will move it out if needed. */ i915_ttm_adjust_lru(obj); } static void i915_ttm_adjust_lru(struct drm_i915_gem_object *obj) { struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); /* * Don't manipulate the TTM LRUs while in TTM bo destruction. * We're called through i915_ttm_delete_mem_notify(). */ if (!kref_read(&bo->kref)) return; /* * Put on the correct LRU list depending on the MADV status */ spin_lock(&bo->bdev->lru_lock); if (obj->mm.madv != I915_MADV_WILLNEED) { bo->priority = I915_TTM_PRIO_PURGE; } else if (!i915_gem_object_has_pages(obj)) { if (bo->priority < I915_TTM_PRIO_HAS_PAGES) bo->priority = I915_TTM_PRIO_HAS_PAGES; } else { if (bo->priority > I915_TTM_PRIO_NO_PAGES) bo->priority = I915_TTM_PRIO_NO_PAGES; } ttm_bo_move_to_lru_tail(bo, bo->resource, NULL); spin_unlock(&bo->bdev->lru_lock); } /* * TTM-backed gem object destruction requires some clarification. * Basically we have two possibilities here. We can either rely on the * i915 delayed destruction and put the TTM object when the object * is idle. This would be detected by TTM which would bypass the * TTM delayed destroy handling. The other approach is to put the TTM * object early and rely on the TTM destroyed handling, and then free * the leftover parts of the GEM object once TTM's destroyed list handling is * complete. For now, we rely on the latter for two reasons: * a) TTM can evict an object even when it's on the delayed destroy list, * which in theory allows for complete eviction. * b) There is work going on in TTM to allow freeing an object even when * it's not idle, and using the TTM destroyed list handling could help us * benefit from that. */ static void i915_ttm_delayed_free(struct drm_i915_gem_object *obj) { if (obj->ttm.created) { ttm_bo_put(i915_gem_to_ttm(obj)); } else { __i915_gem_free_object(obj); call_rcu(&obj->rcu, __i915_gem_free_object_rcu); } } static vm_fault_t vm_fault_ttm(struct vm_fault *vmf) { struct vm_area_struct *area = vmf->vma; struct drm_i915_gem_object *obj = i915_ttm_to_gem(area->vm_private_data); /* Sanity check that we allow writing into this object */ if (unlikely(i915_gem_object_is_readonly(obj) && area->vm_flags & VM_WRITE)) return VM_FAULT_SIGBUS; return ttm_bo_vm_fault(vmf); } static int vm_access_ttm(struct vm_area_struct *area, unsigned long addr, void *buf, int len, int write) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(area->vm_private_data); if (i915_gem_object_is_readonly(obj) && write) return -EACCES; return ttm_bo_vm_access(area, addr, buf, len, write); } static void ttm_vm_open(struct vm_area_struct *vma) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(vma->vm_private_data); GEM_BUG_ON(!obj); i915_gem_object_get(obj); } static void ttm_vm_close(struct vm_area_struct *vma) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(vma->vm_private_data); GEM_BUG_ON(!obj); i915_gem_object_put(obj); } static const struct vm_operations_struct vm_ops_ttm = { .fault = vm_fault_ttm, .access = vm_access_ttm, .open = ttm_vm_open, .close = ttm_vm_close, }; static u64 i915_ttm_mmap_offset(struct drm_i915_gem_object *obj) { /* The ttm_bo must be allocated with I915_BO_ALLOC_USER */ GEM_BUG_ON(!drm_mm_node_allocated(&obj->base.vma_node.vm_node)); return drm_vma_node_offset_addr(&obj->base.vma_node); } static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = { .name = "i915_gem_object_ttm", .get_pages = i915_ttm_get_pages, .put_pages = i915_ttm_put_pages, .truncate = i915_ttm_purge, .adjust_lru = i915_ttm_adjust_lru, .delayed_free = i915_ttm_delayed_free, .migrate = i915_ttm_migrate, .mmap_offset = i915_ttm_mmap_offset, .mmap_ops = &vm_ops_ttm, }; void i915_ttm_bo_destroy(struct ttm_buffer_object *bo) { struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); i915_gem_object_release_memory_region(obj); mutex_destroy(&obj->ttm.get_io_page.lock); if (obj->ttm.created) call_rcu(&obj->rcu, __i915_gem_free_object_rcu); } /** * __i915_gem_ttm_object_init - Initialize a ttm-backed i915 gem object * @mem: The initial memory region for the object. * @obj: The gem object. * @size: Object size in bytes. * @flags: gem object flags. * * Return: 0 on success, negative error code on failure. */ int __i915_gem_ttm_object_init(struct intel_memory_region *mem, struct drm_i915_gem_object *obj, resource_size_t size, resource_size_t page_size, unsigned int flags) { static struct lock_class_key lock_class; struct drm_i915_private *i915 = mem->i915; struct ttm_operation_ctx ctx = { .interruptible = true, .no_wait_gpu = false, }; enum ttm_bo_type bo_type; int ret; drm_gem_private_object_init(&i915->drm, &obj->base, size); i915_gem_object_init(obj, &i915_gem_ttm_obj_ops, &lock_class, flags); i915_gem_object_init_memory_region(obj, mem); i915_gem_object_make_unshrinkable(obj); INIT_RADIX_TREE(&obj->ttm.get_io_page.radix, GFP_KERNEL | __GFP_NOWARN); mutex_init(&obj->ttm.get_io_page.lock); bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device : ttm_bo_type_kernel; obj->base.vma_node.driver_private = i915_gem_to_ttm(obj); /* Forcing the page size is kernel internal only */ GEM_BUG_ON(page_size && obj->mm.n_placements); /* * If this function fails, it will call the destructor, but * our caller still owns the object. So no freeing in the * destructor until obj->ttm.created is true. * Similarly, in delayed_destroy, we can't call ttm_bo_put() * until successful initialization. */ ret = ttm_bo_init_reserved(&i915->bdev, i915_gem_to_ttm(obj), size, bo_type, &i915_sys_placement, page_size >> PAGE_SHIFT, &ctx, NULL, NULL, i915_ttm_bo_destroy); if (ret) return i915_ttm_err_to_gem(ret); obj->ttm.created = true; i915_ttm_adjust_domains_after_move(obj); i915_ttm_adjust_gem_after_move(obj); i915_gem_object_unlock(obj); return 0; } static const struct intel_memory_region_ops ttm_system_region_ops = { .init_object = __i915_gem_ttm_object_init, }; struct intel_memory_region * i915_gem_ttm_system_setup(struct drm_i915_private *i915, u16 type, u16 instance) { struct intel_memory_region *mr; mr = intel_memory_region_create(i915, 0, totalram_pages() << PAGE_SHIFT, PAGE_SIZE, 0, type, instance, &ttm_system_region_ops); if (IS_ERR(mr)) return mr; intel_memory_region_set_name(mr, "system-ttm"); return mr; }