/* * Copyright © 2017 Intel Corporation * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. * */ #include #include "display/intel_frontbuffer.h" #include "pxp/intel_pxp.h" #include "i915_drv.h" #include "i915_gem_clflush.h" #include "i915_gem_context.h" #include "i915_gem_mman.h" #include "i915_gem_object.h" #include "i915_memcpy.h" #include "i915_trace.h" static struct kmem_cache *slab_objects; static const struct drm_gem_object_funcs i915_gem_object_funcs; struct drm_i915_gem_object *i915_gem_object_alloc(void) { struct drm_i915_gem_object *obj; obj = kmem_cache_zalloc(slab_objects, GFP_KERNEL); if (!obj) return NULL; obj->base.funcs = &i915_gem_object_funcs; return obj; } void i915_gem_object_free(struct drm_i915_gem_object *obj) { return kmem_cache_free(slab_objects, obj); } void i915_gem_object_init(struct drm_i915_gem_object *obj, const struct drm_i915_gem_object_ops *ops, struct lock_class_key *key, unsigned flags) { /* * A gem object is embedded both in a struct ttm_buffer_object :/ and * in a drm_i915_gem_object. Make sure they are aliased. */ BUILD_BUG_ON(offsetof(typeof(*obj), base) != offsetof(typeof(*obj), __do_not_access.base)); spin_lock_init(&obj->vma.lock); INIT_LIST_HEAD(&obj->vma.list); INIT_LIST_HEAD(&obj->mm.link); INIT_LIST_HEAD(&obj->lut_list); spin_lock_init(&obj->lut_lock); spin_lock_init(&obj->mmo.lock); obj->mmo.offsets = RB_ROOT; init_rcu_head(&obj->rcu); obj->ops = ops; GEM_BUG_ON(flags & ~I915_BO_ALLOC_FLAGS); obj->flags = flags; obj->mm.madv = I915_MADV_WILLNEED; INIT_RADIX_TREE(&obj->mm.get_page.radix, GFP_KERNEL | __GFP_NOWARN); mutex_init(&obj->mm.get_page.lock); INIT_RADIX_TREE(&obj->mm.get_dma_page.radix, GFP_KERNEL | __GFP_NOWARN); mutex_init(&obj->mm.get_dma_page.lock); } /** * i915_gem_object_fini - Clean up a GEM object initialization * @obj: The gem object to cleanup * * This function cleans up gem object fields that are set up by * drm_gem_private_object_init() and i915_gem_object_init(). * It's primarily intended as a helper for backends that need to * clean up the gem object in separate steps. */ void __i915_gem_object_fini(struct drm_i915_gem_object *obj) { mutex_destroy(&obj->mm.get_page.lock); mutex_destroy(&obj->mm.get_dma_page.lock); dma_resv_fini(&obj->base._resv); } /** * Mark up the object's coherency levels for a given cache_level * @obj: #drm_i915_gem_object * @cache_level: cache level */ void i915_gem_object_set_cache_coherency(struct drm_i915_gem_object *obj, unsigned int cache_level) { struct drm_i915_private *i915 = to_i915(obj->base.dev); obj->cache_level = cache_level; if (cache_level != I915_CACHE_NONE) obj->cache_coherent = (I915_BO_CACHE_COHERENT_FOR_READ | I915_BO_CACHE_COHERENT_FOR_WRITE); else if (HAS_LLC(i915)) obj->cache_coherent = I915_BO_CACHE_COHERENT_FOR_READ; else obj->cache_coherent = 0; obj->cache_dirty = !(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE) && !IS_DGFX(i915); } bool i915_gem_object_can_bypass_llc(struct drm_i915_gem_object *obj) { struct drm_i915_private *i915 = to_i915(obj->base.dev); /* * This is purely from a security perspective, so we simply don't care * about non-userspace objects being able to bypass the LLC. */ if (!(obj->flags & I915_BO_ALLOC_USER)) return false; /* * EHL and JSL add the 'Bypass LLC' MOCS entry, which should make it * possible for userspace to bypass the GTT caching bits set by the * kernel, as per the given object cache_level. This is troublesome * since the heavy flush we apply when first gathering the pages is * skipped if the kernel thinks the object is coherent with the GPU. As * a result it might be possible to bypass the cache and read the * contents of the page directly, which could be stale data. If it's * just a case of userspace shooting themselves in the foot then so be * it, but since i915 takes the stance of always zeroing memory before * handing it to userspace, we need to prevent this. */ return IS_JSL_EHL(i915); } static void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file) { struct drm_i915_gem_object *obj = to_intel_bo(gem); struct drm_i915_file_private *fpriv = file->driver_priv; struct i915_lut_handle bookmark = {}; struct i915_mmap_offset *mmo, *mn; struct i915_lut_handle *lut, *ln; LIST_HEAD(close); spin_lock(&obj->lut_lock); list_for_each_entry_safe(lut, ln, &obj->lut_list, obj_link) { struct i915_gem_context *ctx = lut->ctx; if (ctx && ctx->file_priv == fpriv) { i915_gem_context_get(ctx); list_move(&lut->obj_link, &close); } /* Break long locks, and carefully continue on from this spot */ if (&ln->obj_link != &obj->lut_list) { list_add_tail(&bookmark.obj_link, &ln->obj_link); if (cond_resched_lock(&obj->lut_lock)) list_safe_reset_next(&bookmark, ln, obj_link); __list_del_entry(&bookmark.obj_link); } } spin_unlock(&obj->lut_lock); spin_lock(&obj->mmo.lock); rbtree_postorder_for_each_entry_safe(mmo, mn, &obj->mmo.offsets, offset) drm_vma_node_revoke(&mmo->vma_node, file); spin_unlock(&obj->mmo.lock); list_for_each_entry_safe(lut, ln, &close, obj_link) { struct i915_gem_context *ctx = lut->ctx; struct i915_vma *vma; /* * We allow the process to have multiple handles to the same * vma, in the same fd namespace, by virtue of flink/open. */ mutex_lock(&ctx->lut_mutex); vma = radix_tree_delete(&ctx->handles_vma, lut->handle); if (vma) { GEM_BUG_ON(vma->obj != obj); GEM_BUG_ON(!atomic_read(&vma->open_count)); i915_vma_close(vma); } mutex_unlock(&ctx->lut_mutex); i915_gem_context_put(lut->ctx); i915_lut_handle_free(lut); i915_gem_object_put(obj); } } void __i915_gem_free_object_rcu(struct rcu_head *head) { struct drm_i915_gem_object *obj = container_of(head, typeof(*obj), rcu); struct drm_i915_private *i915 = to_i915(obj->base.dev); i915_gem_object_free(obj); GEM_BUG_ON(!atomic_read(&i915->mm.free_count)); atomic_dec(&i915->mm.free_count); } static void __i915_gem_object_free_mmaps(struct drm_i915_gem_object *obj) { /* Skip serialisation and waking the device if known to be not used. */ if (obj->userfault_count) i915_gem_object_release_mmap_gtt(obj); if (!RB_EMPTY_ROOT(&obj->mmo.offsets)) { struct i915_mmap_offset *mmo, *mn; i915_gem_object_release_mmap_offset(obj); rbtree_postorder_for_each_entry_safe(mmo, mn, &obj->mmo.offsets, offset) { drm_vma_offset_remove(obj->base.dev->vma_offset_manager, &mmo->vma_node); kfree(mmo); } obj->mmo.offsets = RB_ROOT; } } /** * __i915_gem_object_pages_fini - Clean up pages use of a gem object * @obj: The gem object to clean up * * This function cleans up usage of the object mm.pages member. It * is intended for backends that need to clean up a gem object in * separate steps and needs to be called when the object is idle before * the object's backing memory is freed. */ void __i915_gem_object_pages_fini(struct drm_i915_gem_object *obj) { if (!list_empty(&obj->vma.list)) { struct i915_vma *vma; /* * Note that the vma keeps an object reference while * it is active, so it *should* not sleep while we * destroy it. Our debug code errs insits it *might*. * For the moment, play along. */ spin_lock(&obj->vma.lock); while ((vma = list_first_entry_or_null(&obj->vma.list, struct i915_vma, obj_link))) { GEM_BUG_ON(vma->obj != obj); spin_unlock(&obj->vma.lock); __i915_vma_put(vma); spin_lock(&obj->vma.lock); } spin_unlock(&obj->vma.lock); } __i915_gem_object_free_mmaps(obj); atomic_set(&obj->mm.pages_pin_count, 0); __i915_gem_object_put_pages(obj); GEM_BUG_ON(i915_gem_object_has_pages(obj)); } void __i915_gem_free_object(struct drm_i915_gem_object *obj) { trace_i915_gem_object_destroy(obj); GEM_BUG_ON(!list_empty(&obj->lut_list)); bitmap_free(obj->bit_17); if (obj->base.import_attach) drm_prime_gem_destroy(&obj->base, NULL); drm_gem_free_mmap_offset(&obj->base); if (obj->ops->release) obj->ops->release(obj); if (obj->mm.n_placements > 1) kfree(obj->mm.placements); if (obj->shares_resv_from) i915_vm_resv_put(obj->shares_resv_from); __i915_gem_object_fini(obj); } static void __i915_gem_free_objects(struct drm_i915_private *i915, struct llist_node *freed) { struct drm_i915_gem_object *obj, *on; llist_for_each_entry_safe(obj, on, freed, freed) { might_sleep(); if (obj->ops->delayed_free) { obj->ops->delayed_free(obj); continue; } __i915_gem_object_pages_fini(obj); __i915_gem_free_object(obj); /* But keep the pointer alive for RCU-protected lookups */ call_rcu(&obj->rcu, __i915_gem_free_object_rcu); cond_resched(); } } void i915_gem_flush_free_objects(struct drm_i915_private *i915) { struct llist_node *freed = llist_del_all(&i915->mm.free_list); if (unlikely(freed)) __i915_gem_free_objects(i915, freed); } static void __i915_gem_free_work(struct work_struct *work) { struct drm_i915_private *i915 = container_of(work, struct drm_i915_private, mm.free_work); i915_gem_flush_free_objects(i915); } static void i915_gem_free_object(struct drm_gem_object *gem_obj) { struct drm_i915_gem_object *obj = to_intel_bo(gem_obj); struct drm_i915_private *i915 = to_i915(obj->base.dev); GEM_BUG_ON(i915_gem_object_is_framebuffer(obj)); /* * Before we free the object, make sure any pure RCU-only * read-side critical sections are complete, e.g. * i915_gem_busy_ioctl(). For the corresponding synchronized * lookup see i915_gem_object_lookup_rcu(). */ atomic_inc(&i915->mm.free_count); /* * Since we require blocking on struct_mutex to unbind the freed * object from the GPU before releasing resources back to the * system, we can not do that directly from the RCU callback (which may * be a softirq context), but must instead then defer that work onto a * kthread. We use the RCU callback rather than move the freed object * directly onto the work queue so that we can mix between using the * worker and performing frees directly from subsequent allocations for * crude but effective memory throttling. */ if (llist_add(&obj->freed, &i915->mm.free_list)) queue_work(i915->wq, &i915->mm.free_work); } void __i915_gem_object_flush_frontbuffer(struct drm_i915_gem_object *obj, enum fb_op_origin origin) { struct intel_frontbuffer *front; front = __intel_frontbuffer_get(obj); if (front) { intel_frontbuffer_flush(front, origin); intel_frontbuffer_put(front); } } void __i915_gem_object_invalidate_frontbuffer(struct drm_i915_gem_object *obj, enum fb_op_origin origin) { struct intel_frontbuffer *front; front = __intel_frontbuffer_get(obj); if (front) { intel_frontbuffer_invalidate(front, origin); intel_frontbuffer_put(front); } } static void i915_gem_object_read_from_page_kmap(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size) { void *src_map; void *src_ptr; src_map = kmap_atomic(i915_gem_object_get_page(obj, offset >> PAGE_SHIFT)); src_ptr = src_map + offset_in_page(offset); if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ)) drm_clflush_virt_range(src_ptr, size); memcpy(dst, src_ptr, size); kunmap_atomic(src_map); } static void i915_gem_object_read_from_page_iomap(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size) { void __iomem *src_map; void __iomem *src_ptr; dma_addr_t dma = i915_gem_object_get_dma_address(obj, offset >> PAGE_SHIFT); src_map = io_mapping_map_wc(&obj->mm.region->iomap, dma - obj->mm.region->region.start, PAGE_SIZE); src_ptr = src_map + offset_in_page(offset); if (!i915_memcpy_from_wc(dst, (void __force *)src_ptr, size)) memcpy_fromio(dst, src_ptr, size); io_mapping_unmap(src_map); } /** * i915_gem_object_read_from_page - read data from the page of a GEM object * @obj: GEM object to read from * @offset: offset within the object * @dst: buffer to store the read data * @size: size to read * * Reads data from @obj at the specified offset. The requested region to read * from can't cross a page boundary. The caller must ensure that @obj pages * are pinned and that @obj is synced wrt. any related writes. * * Returns 0 on success or -ENODEV if the type of @obj's backing store is * unsupported. */ int i915_gem_object_read_from_page(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size) { GEM_BUG_ON(offset >= obj->base.size); GEM_BUG_ON(offset_in_page(offset) > PAGE_SIZE - size); GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj)); if (i915_gem_object_has_struct_page(obj)) i915_gem_object_read_from_page_kmap(obj, offset, dst, size); else if (i915_gem_object_has_iomem(obj)) i915_gem_object_read_from_page_iomap(obj, offset, dst, size); else return -ENODEV; return 0; } /** * i915_gem_object_evictable - Whether object is likely evictable after unbind. * @obj: The object to check * * This function checks whether the object is likely unvictable after unbind. * If the object is not locked when checking, the result is only advisory. * If the object is locked when checking, and the function returns true, * then an eviction should indeed be possible. But since unlocked vma * unpinning and unbinding is currently possible, the object can actually * become evictable even if this function returns false. * * Return: true if the object may be evictable. False otherwise. */ bool i915_gem_object_evictable(struct drm_i915_gem_object *obj) { struct i915_vma *vma; int pin_count = atomic_read(&obj->mm.pages_pin_count); if (!pin_count) return true; spin_lock(&obj->vma.lock); list_for_each_entry(vma, &obj->vma.list, obj_link) { if (i915_vma_is_pinned(vma)) { spin_unlock(&obj->vma.lock); return false; } if (atomic_read(&vma->pages_count)) pin_count--; } spin_unlock(&obj->vma.lock); GEM_WARN_ON(pin_count < 0); return pin_count == 0; } /** * i915_gem_object_migratable - Whether the object is migratable out of the * current region. * @obj: Pointer to the object. * * Return: Whether the object is allowed to be resident in other * regions than the current while pages are present. */ bool i915_gem_object_migratable(struct drm_i915_gem_object *obj) { struct intel_memory_region *mr = READ_ONCE(obj->mm.region); if (!mr) return false; return obj->mm.n_placements > 1; } /** * i915_gem_object_has_struct_page - Whether the object is page-backed * @obj: The object to query. * * This function should only be called while the object is locked or pinned, * otherwise the page backing may change under the caller. * * Return: True if page-backed, false otherwise. */ bool i915_gem_object_has_struct_page(const struct drm_i915_gem_object *obj) { #ifdef CONFIG_LOCKDEP if (IS_DGFX(to_i915(obj->base.dev)) && i915_gem_object_evictable((void __force *)obj)) assert_object_held_shared(obj); #endif return obj->mem_flags & I915_BO_FLAG_STRUCT_PAGE; } /** * i915_gem_object_has_iomem - Whether the object is iomem-backed * @obj: The object to query. * * This function should only be called while the object is locked or pinned, * otherwise the iomem backing may change under the caller. * * Return: True if iomem-backed, false otherwise. */ bool i915_gem_object_has_iomem(const struct drm_i915_gem_object *obj) { #ifdef CONFIG_LOCKDEP if (IS_DGFX(to_i915(obj->base.dev)) && i915_gem_object_evictable((void __force *)obj)) assert_object_held_shared(obj); #endif return obj->mem_flags & I915_BO_FLAG_IOMEM; } /** * i915_gem_object_can_migrate - Whether an object likely can be migrated * * @obj: The object to migrate * @id: The region intended to migrate to * * Check whether the object backend supports migration to the * given region. Note that pinning may affect the ability to migrate as * returned by this function. * * This function is primarily intended as a helper for checking the * possibility to migrate objects and might be slightly less permissive * than i915_gem_object_migrate() when it comes to objects with the * I915_BO_ALLOC_USER flag set. * * Return: true if migration is possible, false otherwise. */ bool i915_gem_object_can_migrate(struct drm_i915_gem_object *obj, enum intel_region_id id) { struct drm_i915_private *i915 = to_i915(obj->base.dev); unsigned int num_allowed = obj->mm.n_placements; struct intel_memory_region *mr; unsigned int i; GEM_BUG_ON(id >= INTEL_REGION_UNKNOWN); GEM_BUG_ON(obj->mm.madv != I915_MADV_WILLNEED); mr = i915->mm.regions[id]; if (!mr) return false; if (obj->mm.region == mr) return true; if (!i915_gem_object_evictable(obj)) return false; if (!obj->ops->migrate) return false; if (!(obj->flags & I915_BO_ALLOC_USER)) return true; if (num_allowed == 0) return false; for (i = 0; i < num_allowed; ++i) { if (mr == obj->mm.placements[i]) return true; } return false; } /** * i915_gem_object_migrate - Migrate an object to the desired region id * @obj: The object to migrate. * @ww: An optional struct i915_gem_ww_ctx. If NULL, the backend may * not be successful in evicting other objects to make room for this object. * @id: The region id to migrate to. * * Attempt to migrate the object to the desired memory region. The * object backend must support migration and the object may not be * pinned, (explicitly pinned pages or pinned vmas). The object must * be locked. * On successful completion, the object will have pages pointing to * memory in the new region, but an async migration task may not have * completed yet, and to accomplish that, i915_gem_object_wait_migration() * must be called. * * Note: the @ww parameter is not used yet, but included to make sure * callers put some effort into obtaining a valid ww ctx if one is * available. * * Return: 0 on success. Negative error code on failure. In particular may * return -ENXIO on lack of region space, -EDEADLK for deadlock avoidance * if @ww is set, -EINTR or -ERESTARTSYS if signal pending, and * -EBUSY if the object is pinned. */ int i915_gem_object_migrate(struct drm_i915_gem_object *obj, struct i915_gem_ww_ctx *ww, enum intel_region_id id) { struct drm_i915_private *i915 = to_i915(obj->base.dev); struct intel_memory_region *mr; GEM_BUG_ON(id >= INTEL_REGION_UNKNOWN); GEM_BUG_ON(obj->mm.madv != I915_MADV_WILLNEED); assert_object_held(obj); mr = i915->mm.regions[id]; GEM_BUG_ON(!mr); if (!i915_gem_object_can_migrate(obj, id)) return -EINVAL; if (!obj->ops->migrate) { if (GEM_WARN_ON(obj->mm.region != mr)) return -EINVAL; return 0; } return obj->ops->migrate(obj, mr); } /** * i915_gem_object_placement_possible - Check whether the object can be * placed at certain memory type * @obj: Pointer to the object * @type: The memory type to check * * Return: True if the object can be placed in @type. False otherwise. */ bool i915_gem_object_placement_possible(struct drm_i915_gem_object *obj, enum intel_memory_type type) { unsigned int i; if (!obj->mm.n_placements) { switch (type) { case INTEL_MEMORY_LOCAL: return i915_gem_object_has_iomem(obj); case INTEL_MEMORY_SYSTEM: return i915_gem_object_has_pages(obj); default: /* Ignore stolen for now */ GEM_BUG_ON(1); return false; } } for (i = 0; i < obj->mm.n_placements; i++) { if (obj->mm.placements[i]->type == type) return true; } return false; } void i915_gem_init__objects(struct drm_i915_private *i915) { INIT_WORK(&i915->mm.free_work, __i915_gem_free_work); } void i915_objects_module_exit(void) { kmem_cache_destroy(slab_objects); } int __init i915_objects_module_init(void) { slab_objects = KMEM_CACHE(drm_i915_gem_object, SLAB_HWCACHE_ALIGN); if (!slab_objects) return -ENOMEM; return 0; } static const struct drm_gem_object_funcs i915_gem_object_funcs = { .free = i915_gem_free_object, .close = i915_gem_close_object, .export = i915_gem_prime_export, }; #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) #include "selftests/huge_gem_object.c" #include "selftests/huge_pages.c" #include "selftests/i915_gem_migrate.c" #include "selftests/i915_gem_object.c" #include "selftests/i915_gem_coherency.c" #endif