/* * Copyright © 2008-2015 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. * * Authors: * Eric Anholt * */ #include #include #include #include "i915_drv.h" #include "i915_gem_clflush.h" #include "i915_vgpu.h" #include "i915_trace.h" #include "intel_drv.h" #include "intel_frontbuffer.h" #include "intel_mocs.h" #include "i915_gemfs.h" #include #include #include #include #include #include #include #include #include static void i915_gem_flush_free_objects(struct drm_i915_private *i915); static bool cpu_write_needs_clflush(struct drm_i915_gem_object *obj) { if (obj->cache_dirty) return false; if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE)) return true; return obj->pin_display; } static int insert_mappable_node(struct i915_ggtt *ggtt, struct drm_mm_node *node, u32 size) { memset(node, 0, sizeof(*node)); return drm_mm_insert_node_in_range(&ggtt->base.mm, node, size, 0, I915_COLOR_UNEVICTABLE, 0, ggtt->mappable_end, DRM_MM_INSERT_LOW); } static void remove_mappable_node(struct drm_mm_node *node) { drm_mm_remove_node(node); } /* some bookkeeping */ static void i915_gem_info_add_obj(struct drm_i915_private *dev_priv, u64 size) { spin_lock(&dev_priv->mm.object_stat_lock); dev_priv->mm.object_count++; dev_priv->mm.object_memory += size; spin_unlock(&dev_priv->mm.object_stat_lock); } static void i915_gem_info_remove_obj(struct drm_i915_private *dev_priv, u64 size) { spin_lock(&dev_priv->mm.object_stat_lock); dev_priv->mm.object_count--; dev_priv->mm.object_memory -= size; spin_unlock(&dev_priv->mm.object_stat_lock); } static int i915_gem_wait_for_error(struct i915_gpu_error *error) { int ret; might_sleep(); /* * Only wait 10 seconds for the gpu reset to complete to avoid hanging * userspace. If it takes that long something really bad is going on and * we should simply try to bail out and fail as gracefully as possible. */ ret = wait_event_interruptible_timeout(error->reset_queue, !i915_reset_backoff(error), I915_RESET_TIMEOUT); if (ret == 0) { DRM_ERROR("Timed out waiting for the gpu reset to complete\n"); return -EIO; } else if (ret < 0) { return ret; } else { return 0; } } int i915_mutex_lock_interruptible(struct drm_device *dev) { struct drm_i915_private *dev_priv = to_i915(dev); int ret; ret = i915_gem_wait_for_error(&dev_priv->gpu_error); if (ret) return ret; ret = mutex_lock_interruptible(&dev->struct_mutex); if (ret) return ret; return 0; } int i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_private *dev_priv = to_i915(dev); struct i915_ggtt *ggtt = &dev_priv->ggtt; struct drm_i915_gem_get_aperture *args = data; struct i915_vma *vma; u64 pinned; pinned = ggtt->base.reserved; mutex_lock(&dev->struct_mutex); list_for_each_entry(vma, &ggtt->base.active_list, vm_link) if (i915_vma_is_pinned(vma)) pinned += vma->node.size; list_for_each_entry(vma, &ggtt->base.inactive_list, vm_link) if (i915_vma_is_pinned(vma)) pinned += vma->node.size; mutex_unlock(&dev->struct_mutex); args->aper_size = ggtt->base.total; args->aper_available_size = args->aper_size - pinned; return 0; } static int i915_gem_object_get_pages_phys(struct drm_i915_gem_object *obj) { struct address_space *mapping = obj->base.filp->f_mapping; drm_dma_handle_t *phys; struct sg_table *st; struct scatterlist *sg; char *vaddr; int i; int err; if (WARN_ON(i915_gem_object_needs_bit17_swizzle(obj))) return -EINVAL; /* Always aligning to the object size, allows a single allocation * to handle all possible callers, and given typical object sizes, * the alignment of the buddy allocation will naturally match. */ phys = drm_pci_alloc(obj->base.dev, roundup_pow_of_two(obj->base.size), roundup_pow_of_two(obj->base.size)); if (!phys) return -ENOMEM; vaddr = phys->vaddr; for (i = 0; i < obj->base.size / PAGE_SIZE; i++) { struct page *page; char *src; page = shmem_read_mapping_page(mapping, i); if (IS_ERR(page)) { err = PTR_ERR(page); goto err_phys; } src = kmap_atomic(page); memcpy(vaddr, src, PAGE_SIZE); drm_clflush_virt_range(vaddr, PAGE_SIZE); kunmap_atomic(src); put_page(page); vaddr += PAGE_SIZE; } i915_gem_chipset_flush(to_i915(obj->base.dev)); st = kmalloc(sizeof(*st), GFP_KERNEL); if (!st) { err = -ENOMEM; goto err_phys; } if (sg_alloc_table(st, 1, GFP_KERNEL)) { kfree(st); err = -ENOMEM; goto err_phys; } sg = st->sgl; sg->offset = 0; sg->length = obj->base.size; sg_dma_address(sg) = phys->busaddr; sg_dma_len(sg) = obj->base.size; obj->phys_handle = phys; __i915_gem_object_set_pages(obj, st, sg->length); return 0; err_phys: drm_pci_free(obj->base.dev, phys); return err; } static void __start_cpu_write(struct drm_i915_gem_object *obj) { obj->base.read_domains = I915_GEM_DOMAIN_CPU; obj->base.write_domain = I915_GEM_DOMAIN_CPU; if (cpu_write_needs_clflush(obj)) obj->cache_dirty = true; } static void __i915_gem_object_release_shmem(struct drm_i915_gem_object *obj, struct sg_table *pages, bool needs_clflush) { GEM_BUG_ON(obj->mm.madv == __I915_MADV_PURGED); if (obj->mm.madv == I915_MADV_DONTNEED) obj->mm.dirty = false; if (needs_clflush && (obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0 && !(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ)) drm_clflush_sg(pages); __start_cpu_write(obj); } static void i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj, struct sg_table *pages) { __i915_gem_object_release_shmem(obj, pages, false); if (obj->mm.dirty) { struct address_space *mapping = obj->base.filp->f_mapping; char *vaddr = obj->phys_handle->vaddr; int i; for (i = 0; i < obj->base.size / PAGE_SIZE; i++) { struct page *page; char *dst; page = shmem_read_mapping_page(mapping, i); if (IS_ERR(page)) continue; dst = kmap_atomic(page); drm_clflush_virt_range(vaddr, PAGE_SIZE); memcpy(dst, vaddr, PAGE_SIZE); kunmap_atomic(dst); set_page_dirty(page); if (obj->mm.madv == I915_MADV_WILLNEED) mark_page_accessed(page); put_page(page); vaddr += PAGE_SIZE; } obj->mm.dirty = false; } sg_free_table(pages); kfree(pages); drm_pci_free(obj->base.dev, obj->phys_handle); } static void i915_gem_object_release_phys(struct drm_i915_gem_object *obj) { i915_gem_object_unpin_pages(obj); } static const struct drm_i915_gem_object_ops i915_gem_phys_ops = { .get_pages = i915_gem_object_get_pages_phys, .put_pages = i915_gem_object_put_pages_phys, .release = i915_gem_object_release_phys, }; static const struct drm_i915_gem_object_ops i915_gem_object_ops; int i915_gem_object_unbind(struct drm_i915_gem_object *obj) { struct i915_vma *vma; LIST_HEAD(still_in_list); int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); /* Closed vma are removed from the obj->vma_list - but they may * still have an active binding on the object. To remove those we * must wait for all rendering to complete to the object (as unbinding * must anyway), and retire the requests. */ ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED | I915_WAIT_ALL, MAX_SCHEDULE_TIMEOUT, NULL); if (ret) return ret; i915_gem_retire_requests(to_i915(obj->base.dev)); while ((vma = list_first_entry_or_null(&obj->vma_list, struct i915_vma, obj_link))) { list_move_tail(&vma->obj_link, &still_in_list); ret = i915_vma_unbind(vma); if (ret) break; } list_splice(&still_in_list, &obj->vma_list); return ret; } static long i915_gem_object_wait_fence(struct dma_fence *fence, unsigned int flags, long timeout, struct intel_rps_client *rps_client) { struct drm_i915_gem_request *rq; BUILD_BUG_ON(I915_WAIT_INTERRUPTIBLE != 0x1); if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) return timeout; if (!dma_fence_is_i915(fence)) return dma_fence_wait_timeout(fence, flags & I915_WAIT_INTERRUPTIBLE, timeout); rq = to_request(fence); if (i915_gem_request_completed(rq)) goto out; /* This client is about to stall waiting for the GPU. In many cases * this is undesirable and limits the throughput of the system, as * many clients cannot continue processing user input/output whilst * blocked. RPS autotuning may take tens of milliseconds to respond * to the GPU load and thus incurs additional latency for the client. * We can circumvent that by promoting the GPU frequency to maximum * before we wait. This makes the GPU throttle up much more quickly * (good for benchmarks and user experience, e.g. window animations), * but at a cost of spending more power processing the workload * (bad for battery). Not all clients even want their results * immediately and for them we should just let the GPU select its own * frequency to maximise efficiency. To prevent a single client from * forcing the clocks too high for the whole system, we only allow * each client to waitboost once in a busy period. */ if (rps_client) { if (INTEL_GEN(rq->i915) >= 6) gen6_rps_boost(rq, rps_client); else rps_client = NULL; } timeout = i915_wait_request(rq, flags, timeout); out: if (flags & I915_WAIT_LOCKED && i915_gem_request_completed(rq)) i915_gem_request_retire_upto(rq); return timeout; } static long i915_gem_object_wait_reservation(struct reservation_object *resv, unsigned int flags, long timeout, struct intel_rps_client *rps_client) { unsigned int seq = __read_seqcount_begin(&resv->seq); struct dma_fence *excl; bool prune_fences = false; if (flags & I915_WAIT_ALL) { struct dma_fence **shared; unsigned int count, i; int ret; ret = reservation_object_get_fences_rcu(resv, &excl, &count, &shared); if (ret) return ret; for (i = 0; i < count; i++) { timeout = i915_gem_object_wait_fence(shared[i], flags, timeout, rps_client); if (timeout < 0) break; dma_fence_put(shared[i]); } for (; i < count; i++) dma_fence_put(shared[i]); kfree(shared); prune_fences = count && timeout >= 0; } else { excl = reservation_object_get_excl_rcu(resv); } if (excl && timeout >= 0) { timeout = i915_gem_object_wait_fence(excl, flags, timeout, rps_client); prune_fences = timeout >= 0; } dma_fence_put(excl); /* Oportunistically prune the fences iff we know they have *all* been * signaled and that the reservation object has not been changed (i.e. * no new fences have been added). */ if (prune_fences && !__read_seqcount_retry(&resv->seq, seq)) { if (reservation_object_trylock(resv)) { if (!__read_seqcount_retry(&resv->seq, seq)) reservation_object_add_excl_fence(resv, NULL); reservation_object_unlock(resv); } } return timeout; } static void __fence_set_priority(struct dma_fence *fence, int prio) { struct drm_i915_gem_request *rq; struct intel_engine_cs *engine; if (!dma_fence_is_i915(fence)) return; rq = to_request(fence); engine = rq->engine; if (!engine->schedule) return; engine->schedule(rq, prio); } static void fence_set_priority(struct dma_fence *fence, int prio) { /* Recurse once into a fence-array */ if (dma_fence_is_array(fence)) { struct dma_fence_array *array = to_dma_fence_array(fence); int i; for (i = 0; i < array->num_fences; i++) __fence_set_priority(array->fences[i], prio); } else { __fence_set_priority(fence, prio); } } int i915_gem_object_wait_priority(struct drm_i915_gem_object *obj, unsigned int flags, int prio) { struct dma_fence *excl; if (flags & I915_WAIT_ALL) { struct dma_fence **shared; unsigned int count, i; int ret; ret = reservation_object_get_fences_rcu(obj->resv, &excl, &count, &shared); if (ret) return ret; for (i = 0; i < count; i++) { fence_set_priority(shared[i], prio); dma_fence_put(shared[i]); } kfree(shared); } else { excl = reservation_object_get_excl_rcu(obj->resv); } if (excl) { fence_set_priority(excl, prio); dma_fence_put(excl); } return 0; } /** * Waits for rendering to the object to be completed * @obj: i915 gem object * @flags: how to wait (under a lock, for all rendering or just for writes etc) * @timeout: how long to wait * @rps: client (user process) to charge for any waitboosting */ int i915_gem_object_wait(struct drm_i915_gem_object *obj, unsigned int flags, long timeout, struct intel_rps_client *rps_client) { might_sleep(); #if IS_ENABLED(CONFIG_LOCKDEP) GEM_BUG_ON(debug_locks && !!lockdep_is_held(&obj->base.dev->struct_mutex) != !!(flags & I915_WAIT_LOCKED)); #endif GEM_BUG_ON(timeout < 0); timeout = i915_gem_object_wait_reservation(obj->resv, flags, timeout, rps_client); return timeout < 0 ? timeout : 0; } static struct intel_rps_client *to_rps_client(struct drm_file *file) { struct drm_i915_file_private *fpriv = file->driver_priv; return &fpriv->rps_client; } static int i915_gem_phys_pwrite(struct drm_i915_gem_object *obj, struct drm_i915_gem_pwrite *args, struct drm_file *file) { void *vaddr = obj->phys_handle->vaddr + args->offset; char __user *user_data = u64_to_user_ptr(args->data_ptr); /* We manually control the domain here and pretend that it * remains coherent i.e. in the GTT domain, like shmem_pwrite. */ intel_fb_obj_invalidate(obj, ORIGIN_CPU); if (copy_from_user(vaddr, user_data, args->size)) return -EFAULT; drm_clflush_virt_range(vaddr, args->size); i915_gem_chipset_flush(to_i915(obj->base.dev)); intel_fb_obj_flush(obj, ORIGIN_CPU); return 0; } void *i915_gem_object_alloc(struct drm_i915_private *dev_priv) { return kmem_cache_zalloc(dev_priv->objects, GFP_KERNEL); } void i915_gem_object_free(struct drm_i915_gem_object *obj) { struct drm_i915_private *dev_priv = to_i915(obj->base.dev); kmem_cache_free(dev_priv->objects, obj); } static int i915_gem_create(struct drm_file *file, struct drm_i915_private *dev_priv, uint64_t size, uint32_t *handle_p) { struct drm_i915_gem_object *obj; int ret; u32 handle; size = roundup(size, PAGE_SIZE); if (size == 0) return -EINVAL; /* Allocate the new object */ obj = i915_gem_object_create(dev_priv, size); if (IS_ERR(obj)) return PTR_ERR(obj); ret = drm_gem_handle_create(file, &obj->base, &handle); /* drop reference from allocate - handle holds it now */ i915_gem_object_put(obj); if (ret) return ret; *handle_p = handle; return 0; } int i915_gem_dumb_create(struct drm_file *file, struct drm_device *dev, struct drm_mode_create_dumb *args) { /* have to work out size/pitch and return them */ args->pitch = ALIGN(args->width * DIV_ROUND_UP(args->bpp, 8), 64); args->size = args->pitch * args->height; return i915_gem_create(file, to_i915(dev), args->size, &args->handle); } static bool gpu_write_needs_clflush(struct drm_i915_gem_object *obj) { return !(obj->cache_level == I915_CACHE_NONE || obj->cache_level == I915_CACHE_WT); } /** * Creates a new mm object and returns a handle to it. * @dev: drm device pointer * @data: ioctl data blob * @file: drm file pointer */ int i915_gem_create_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_private *dev_priv = to_i915(dev); struct drm_i915_gem_create *args = data; i915_gem_flush_free_objects(dev_priv); return i915_gem_create(file, dev_priv, args->size, &args->handle); } static inline enum fb_op_origin fb_write_origin(struct drm_i915_gem_object *obj, unsigned int domain) { return (domain == I915_GEM_DOMAIN_GTT ? obj->frontbuffer_ggtt_origin : ORIGIN_CPU); } static void flush_write_domain(struct drm_i915_gem_object *obj, unsigned int flush_domains) { struct drm_i915_private *dev_priv = to_i915(obj->base.dev); if (!(obj->base.write_domain & flush_domains)) return; /* No actual flushing is required for the GTT write domain. Writes * to it "immediately" go to main memory as far as we know, so there's * no chipset flush. It also doesn't land in render cache. * * However, we do have to enforce the order so that all writes through * the GTT land before any writes to the device, such as updates to * the GATT itself. * * We also have to wait a bit for the writes to land from the GTT. * An uncached read (i.e. mmio) seems to be ideal for the round-trip * timing. This issue has only been observed when switching quickly * between GTT writes and CPU reads from inside the kernel on recent hw, * and it appears to only affect discrete GTT blocks (i.e. on LLC * system agents we cannot reproduce this behaviour). */ wmb(); switch (obj->base.write_domain) { case I915_GEM_DOMAIN_GTT: if (!HAS_LLC(dev_priv)) { intel_runtime_pm_get(dev_priv); spin_lock_irq(&dev_priv->uncore.lock); POSTING_READ_FW(RING_HEAD(dev_priv->engine[RCS]->mmio_base)); spin_unlock_irq(&dev_priv->uncore.lock); intel_runtime_pm_put(dev_priv); } intel_fb_obj_flush(obj, fb_write_origin(obj, I915_GEM_DOMAIN_GTT)); break; case I915_GEM_DOMAIN_CPU: i915_gem_clflush_object(obj, I915_CLFLUSH_SYNC); break; case I915_GEM_DOMAIN_RENDER: if (gpu_write_needs_clflush(obj)) obj->cache_dirty = true; break; } obj->base.write_domain = 0; } static inline int __copy_to_user_swizzled(char __user *cpu_vaddr, const char *gpu_vaddr, int gpu_offset, int length) { int ret, cpu_offset = 0; while (length > 0) { int cacheline_end = ALIGN(gpu_offset + 1, 64); int this_length = min(cacheline_end - gpu_offset, length); int swizzled_gpu_offset = gpu_offset ^ 64; ret = __copy_to_user(cpu_vaddr + cpu_offset, gpu_vaddr + swizzled_gpu_offset, this_length); if (ret) return ret + length; cpu_offset += this_length; gpu_offset += this_length; length -= this_length; } return 0; } static inline int __copy_from_user_swizzled(char *gpu_vaddr, int gpu_offset, const char __user *cpu_vaddr, int length) { int ret, cpu_offset = 0; while (length > 0) { int cacheline_end = ALIGN(gpu_offset + 1, 64); int this_length = min(cacheline_end - gpu_offset, length); int swizzled_gpu_offset = gpu_offset ^ 64; ret = __copy_from_user(gpu_vaddr + swizzled_gpu_offset, cpu_vaddr + cpu_offset, this_length); if (ret) return ret + length; cpu_offset += this_length; gpu_offset += this_length; length -= this_length; } return 0; } /* * Pins the specified object's pages and synchronizes the object with * GPU accesses. Sets needs_clflush to non-zero if the caller should * flush the object from the CPU cache. */ int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj, unsigned int *needs_clflush) { int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); *needs_clflush = 0; if (!i915_gem_object_has_struct_page(obj)) return -ENODEV; ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED, MAX_SCHEDULE_TIMEOUT, NULL); if (ret) return ret; ret = i915_gem_object_pin_pages(obj); if (ret) return ret; if (obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ || !static_cpu_has(X86_FEATURE_CLFLUSH)) { ret = i915_gem_object_set_to_cpu_domain(obj, false); if (ret) goto err_unpin; else goto out; } flush_write_domain(obj, ~I915_GEM_DOMAIN_CPU); /* If we're not in the cpu read domain, set ourself into the gtt * read domain and manually flush cachelines (if required). This * optimizes for the case when the gpu will dirty the data * anyway again before the next pread happens. */ if (!obj->cache_dirty && !(obj->base.read_domains & I915_GEM_DOMAIN_CPU)) *needs_clflush = CLFLUSH_BEFORE; out: /* return with the pages pinned */ return 0; err_unpin: i915_gem_object_unpin_pages(obj); return ret; } int i915_gem_obj_prepare_shmem_write(struct drm_i915_gem_object *obj, unsigned int *needs_clflush) { int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); *needs_clflush = 0; if (!i915_gem_object_has_struct_page(obj)) return -ENODEV; ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED | I915_WAIT_ALL, MAX_SCHEDULE_TIMEOUT, NULL); if (ret) return ret; ret = i915_gem_object_pin_pages(obj); if (ret) return ret; if (obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE || !static_cpu_has(X86_FEATURE_CLFLUSH)) { ret = i915_gem_object_set_to_cpu_domain(obj, true); if (ret) goto err_unpin; else goto out; } flush_write_domain(obj, ~I915_GEM_DOMAIN_CPU); /* If we're not in the cpu write domain, set ourself into the * gtt write domain and manually flush cachelines (as required). * This optimizes for the case when the gpu will use the data * right away and we therefore have to clflush anyway. */ if (!obj->cache_dirty) { *needs_clflush |= CLFLUSH_AFTER; /* * Same trick applies to invalidate partially written * cachelines read before writing. */ if (!(obj->base.read_domains & I915_GEM_DOMAIN_CPU)) *needs_clflush |= CLFLUSH_BEFORE; } out: intel_fb_obj_invalidate(obj, ORIGIN_CPU); obj->mm.dirty = true; /* return with the pages pinned */ return 0; err_unpin: i915_gem_object_unpin_pages(obj); return ret; } static void shmem_clflush_swizzled_range(char *addr, unsigned long length, bool swizzled) { if (unlikely(swizzled)) { unsigned long start = (unsigned long) addr; unsigned long end = (unsigned long) addr + length; /* For swizzling simply ensure that we always flush both * channels. Lame, but simple and it works. Swizzled * pwrite/pread is far from a hotpath - current userspace * doesn't use it at all. */ start = round_down(start, 128); end = round_up(end, 128); drm_clflush_virt_range((void *)start, end - start); } else { drm_clflush_virt_range(addr, length); } } /* Only difference to the fast-path function is that this can handle bit17 * and uses non-atomic copy and kmap functions. */ static int shmem_pread_slow(struct page *page, int offset, int length, char __user *user_data, bool page_do_bit17_swizzling, bool needs_clflush) { char *vaddr; int ret; vaddr = kmap(page); if (needs_clflush) shmem_clflush_swizzled_range(vaddr + offset, length, page_do_bit17_swizzling); if (page_do_bit17_swizzling) ret = __copy_to_user_swizzled(user_data, vaddr, offset, length); else ret = __copy_to_user(user_data, vaddr + offset, length); kunmap(page); return ret ? - EFAULT : 0; } static int shmem_pread(struct page *page, int offset, int length, char __user *user_data, bool page_do_bit17_swizzling, bool needs_clflush) { int ret; ret = -ENODEV; if (!page_do_bit17_swizzling) { char *vaddr = kmap_atomic(page); if (needs_clflush) drm_clflush_virt_range(vaddr + offset, length); ret = __copy_to_user_inatomic(user_data, vaddr + offset, length); kunmap_atomic(vaddr); } if (ret == 0) return 0; return shmem_pread_slow(page, offset, length, user_data, page_do_bit17_swizzling, needs_clflush); } static int i915_gem_shmem_pread(struct drm_i915_gem_object *obj, struct drm_i915_gem_pread *args) { char __user *user_data; u64 remain; unsigned int obj_do_bit17_swizzling; unsigned int needs_clflush; unsigned int idx, offset; int ret; obj_do_bit17_swizzling = 0; if (i915_gem_object_needs_bit17_swizzle(obj)) obj_do_bit17_swizzling = BIT(17); ret = mutex_lock_interruptible(&obj->base.dev->struct_mutex); if (ret) return ret; ret = i915_gem_obj_prepare_shmem_read(obj, &needs_clflush); mutex_unlock(&obj->base.dev->struct_mutex); if (ret) return ret; remain = args->size; user_data = u64_to_user_ptr(args->data_ptr); offset = offset_in_page(args->offset); for (idx = args->offset >> PAGE_SHIFT; remain; idx++) { struct page *page = i915_gem_object_get_page(obj, idx); int length; length = remain; if (offset + length > PAGE_SIZE) length = PAGE_SIZE - offset; ret = shmem_pread(page, offset, length, user_data, page_to_phys(page) & obj_do_bit17_swizzling, needs_clflush); if (ret) break; remain -= length; user_data += length; offset = 0; } i915_gem_obj_finish_shmem_access(obj); return ret; } static inline bool gtt_user_read(struct io_mapping *mapping, loff_t base, int offset, char __user *user_data, int length) { void __iomem *vaddr; unsigned long unwritten; /* We can use the cpu mem copy function because this is X86. */ vaddr = io_mapping_map_atomic_wc(mapping, base); unwritten = __copy_to_user_inatomic(user_data, (void __force *)vaddr + offset, length); io_mapping_unmap_atomic(vaddr); if (unwritten) { vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE); unwritten = copy_to_user(user_data, (void __force *)vaddr + offset, length); io_mapping_unmap(vaddr); } return unwritten; } static int i915_gem_gtt_pread(struct drm_i915_gem_object *obj, const struct drm_i915_gem_pread *args) { struct drm_i915_private *i915 = to_i915(obj->base.dev); struct i915_ggtt *ggtt = &i915->ggtt; struct drm_mm_node node; struct i915_vma *vma; void __user *user_data; u64 remain, offset; int ret; ret = mutex_lock_interruptible(&i915->drm.struct_mutex); if (ret) return ret; intel_runtime_pm_get(i915); vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, PIN_MAPPABLE | PIN_NONFAULT | PIN_NONBLOCK); if (!IS_ERR(vma)) { node.start = i915_ggtt_offset(vma); node.allocated = false; ret = i915_vma_put_fence(vma); if (ret) { i915_vma_unpin(vma); vma = ERR_PTR(ret); } } if (IS_ERR(vma)) { ret = insert_mappable_node(ggtt, &node, PAGE_SIZE); if (ret) goto out_unlock; GEM_BUG_ON(!node.allocated); } ret = i915_gem_object_set_to_gtt_domain(obj, false); if (ret) goto out_unpin; mutex_unlock(&i915->drm.struct_mutex); user_data = u64_to_user_ptr(args->data_ptr); remain = args->size; offset = args->offset; while (remain > 0) { /* Operation in this page * * page_base = page offset within aperture * page_offset = offset within page * page_length = bytes to copy for this page */ u32 page_base = node.start; unsigned page_offset = offset_in_page(offset); unsigned page_length = PAGE_SIZE - page_offset; page_length = remain < page_length ? remain : page_length; if (node.allocated) { wmb(); ggtt->base.insert_page(&ggtt->base, i915_gem_object_get_dma_address(obj, offset >> PAGE_SHIFT), node.start, I915_CACHE_NONE, 0); wmb(); } else { page_base += offset & PAGE_MASK; } if (gtt_user_read(&ggtt->mappable, page_base, page_offset, user_data, page_length)) { ret = -EFAULT; break; } remain -= page_length; user_data += page_length; offset += page_length; } mutex_lock(&i915->drm.struct_mutex); out_unpin: if (node.allocated) { wmb(); ggtt->base.clear_range(&ggtt->base, node.start, node.size); remove_mappable_node(&node); } else { i915_vma_unpin(vma); } out_unlock: intel_runtime_pm_put(i915); mutex_unlock(&i915->drm.struct_mutex); return ret; } /** * Reads data from the object referenced by handle. * @dev: drm device pointer * @data: ioctl data blob * @file: drm file pointer * * On error, the contents of *data are undefined. */ int i915_gem_pread_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_pread *args = data; struct drm_i915_gem_object *obj; int ret; if (args->size == 0) return 0; if (!access_ok(VERIFY_WRITE, u64_to_user_ptr(args->data_ptr), args->size)) return -EFAULT; obj = i915_gem_object_lookup(file, args->handle); if (!obj) return -ENOENT; /* Bounds check source. */ if (range_overflows_t(u64, args->offset, args->size, obj->base.size)) { ret = -EINVAL; goto out; } trace_i915_gem_object_pread(obj, args->offset, args->size); ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT, to_rps_client(file)); if (ret) goto out; ret = i915_gem_object_pin_pages(obj); if (ret) goto out; ret = i915_gem_shmem_pread(obj, args); if (ret == -EFAULT || ret == -ENODEV) ret = i915_gem_gtt_pread(obj, args); i915_gem_object_unpin_pages(obj); out: i915_gem_object_put(obj); return ret; } /* This is the fast write path which cannot handle * page faults in the source data */ static inline bool ggtt_write(struct io_mapping *mapping, loff_t base, int offset, char __user *user_data, int length) { void __iomem *vaddr; unsigned long unwritten; /* We can use the cpu mem copy function because this is X86. */ vaddr = io_mapping_map_atomic_wc(mapping, base); unwritten = __copy_from_user_inatomic_nocache((void __force *)vaddr + offset, user_data, length); io_mapping_unmap_atomic(vaddr); if (unwritten) { vaddr = io_mapping_map_wc(mapping, base, PAGE_SIZE); unwritten = copy_from_user((void __force *)vaddr + offset, user_data, length); io_mapping_unmap(vaddr); } return unwritten; } /** * This is the fast pwrite path, where we copy the data directly from the * user into the GTT, uncached. * @obj: i915 GEM object * @args: pwrite arguments structure */ static int i915_gem_gtt_pwrite_fast(struct drm_i915_gem_object *obj, const struct drm_i915_gem_pwrite *args) { struct drm_i915_private *i915 = to_i915(obj->base.dev); struct i915_ggtt *ggtt = &i915->ggtt; struct drm_mm_node node; struct i915_vma *vma; u64 remain, offset; void __user *user_data; int ret; ret = mutex_lock_interruptible(&i915->drm.struct_mutex); if (ret) return ret; intel_runtime_pm_get(i915); vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, PIN_MAPPABLE | PIN_NONFAULT | PIN_NONBLOCK); if (!IS_ERR(vma)) { node.start = i915_ggtt_offset(vma); node.allocated = false; ret = i915_vma_put_fence(vma); if (ret) { i915_vma_unpin(vma); vma = ERR_PTR(ret); } } if (IS_ERR(vma)) { ret = insert_mappable_node(ggtt, &node, PAGE_SIZE); if (ret) goto out_unlock; GEM_BUG_ON(!node.allocated); } ret = i915_gem_object_set_to_gtt_domain(obj, true); if (ret) goto out_unpin; mutex_unlock(&i915->drm.struct_mutex); intel_fb_obj_invalidate(obj, ORIGIN_CPU); user_data = u64_to_user_ptr(args->data_ptr); offset = args->offset; remain = args->size; while (remain) { /* Operation in this page * * page_base = page offset within aperture * page_offset = offset within page * page_length = bytes to copy for this page */ u32 page_base = node.start; unsigned int page_offset = offset_in_page(offset); unsigned int page_length = PAGE_SIZE - page_offset; page_length = remain < page_length ? remain : page_length; if (node.allocated) { wmb(); /* flush the write before we modify the GGTT */ ggtt->base.insert_page(&ggtt->base, i915_gem_object_get_dma_address(obj, offset >> PAGE_SHIFT), node.start, I915_CACHE_NONE, 0); wmb(); /* flush modifications to the GGTT (insert_page) */ } else { page_base += offset & PAGE_MASK; } /* If we get a fault while copying data, then (presumably) our * source page isn't available. Return the error and we'll * retry in the slow path. * If the object is non-shmem backed, we retry again with the * path that handles page fault. */ if (ggtt_write(&ggtt->mappable, page_base, page_offset, user_data, page_length)) { ret = -EFAULT; break; } remain -= page_length; user_data += page_length; offset += page_length; } intel_fb_obj_flush(obj, ORIGIN_CPU); mutex_lock(&i915->drm.struct_mutex); out_unpin: if (node.allocated) { wmb(); ggtt->base.clear_range(&ggtt->base, node.start, node.size); remove_mappable_node(&node); } else { i915_vma_unpin(vma); } out_unlock: intel_runtime_pm_put(i915); mutex_unlock(&i915->drm.struct_mutex); return ret; } static int shmem_pwrite_slow(struct page *page, int offset, int length, char __user *user_data, bool page_do_bit17_swizzling, bool needs_clflush_before, bool needs_clflush_after) { char *vaddr; int ret; vaddr = kmap(page); if (unlikely(needs_clflush_before || page_do_bit17_swizzling)) shmem_clflush_swizzled_range(vaddr + offset, length, page_do_bit17_swizzling); if (page_do_bit17_swizzling) ret = __copy_from_user_swizzled(vaddr, offset, user_data, length); else ret = __copy_from_user(vaddr + offset, user_data, length); if (needs_clflush_after) shmem_clflush_swizzled_range(vaddr + offset, length, page_do_bit17_swizzling); kunmap(page); return ret ? -EFAULT : 0; } /* Per-page copy function for the shmem pwrite fastpath. * Flushes invalid cachelines before writing to the target if * needs_clflush_before is set and flushes out any written cachelines after * writing if needs_clflush is set. */ static int shmem_pwrite(struct page *page, int offset, int len, char __user *user_data, bool page_do_bit17_swizzling, bool needs_clflush_before, bool needs_clflush_after) { int ret; ret = -ENODEV; if (!page_do_bit17_swizzling) { char *vaddr = kmap_atomic(page); if (needs_clflush_before) drm_clflush_virt_range(vaddr + offset, len); ret = __copy_from_user_inatomic(vaddr + offset, user_data, len); if (needs_clflush_after) drm_clflush_virt_range(vaddr + offset, len); kunmap_atomic(vaddr); } if (ret == 0) return ret; return shmem_pwrite_slow(page, offset, len, user_data, page_do_bit17_swizzling, needs_clflush_before, needs_clflush_after); } static int i915_gem_shmem_pwrite(struct drm_i915_gem_object *obj, const struct drm_i915_gem_pwrite *args) { struct drm_i915_private *i915 = to_i915(obj->base.dev); void __user *user_data; u64 remain; unsigned int obj_do_bit17_swizzling; unsigned int partial_cacheline_write; unsigned int needs_clflush; unsigned int offset, idx; int ret; ret = mutex_lock_interruptible(&i915->drm.struct_mutex); if (ret) return ret; ret = i915_gem_obj_prepare_shmem_write(obj, &needs_clflush); mutex_unlock(&i915->drm.struct_mutex); if (ret) return ret; obj_do_bit17_swizzling = 0; if (i915_gem_object_needs_bit17_swizzle(obj)) obj_do_bit17_swizzling = BIT(17); /* If we don't overwrite a cacheline completely we need to be * careful to have up-to-date data by first clflushing. Don't * overcomplicate things and flush the entire patch. */ partial_cacheline_write = 0; if (needs_clflush & CLFLUSH_BEFORE) partial_cacheline_write = boot_cpu_data.x86_clflush_size - 1; user_data = u64_to_user_ptr(args->data_ptr); remain = args->size; offset = offset_in_page(args->offset); for (idx = args->offset >> PAGE_SHIFT; remain; idx++) { struct page *page = i915_gem_object_get_page(obj, idx); int length; length = remain; if (offset + length > PAGE_SIZE) length = PAGE_SIZE - offset; ret = shmem_pwrite(page, offset, length, user_data, page_to_phys(page) & obj_do_bit17_swizzling, (offset | length) & partial_cacheline_write, needs_clflush & CLFLUSH_AFTER); if (ret) break; remain -= length; user_data += length; offset = 0; } intel_fb_obj_flush(obj, ORIGIN_CPU); i915_gem_obj_finish_shmem_access(obj); return ret; } /** * Writes data to the object referenced by handle. * @dev: drm device * @data: ioctl data blob * @file: drm file * * On error, the contents of the buffer that were to be modified are undefined. */ int i915_gem_pwrite_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_pwrite *args = data; struct drm_i915_gem_object *obj; int ret; if (args->size == 0) return 0; if (!access_ok(VERIFY_READ, u64_to_user_ptr(args->data_ptr), args->size)) return -EFAULT; obj = i915_gem_object_lookup(file, args->handle); if (!obj) return -ENOENT; /* Bounds check destination. */ if (range_overflows_t(u64, args->offset, args->size, obj->base.size)) { ret = -EINVAL; goto err; } trace_i915_gem_object_pwrite(obj, args->offset, args->size); ret = -ENODEV; if (obj->ops->pwrite) ret = obj->ops->pwrite(obj, args); if (ret != -ENODEV) goto err; ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_ALL, MAX_SCHEDULE_TIMEOUT, to_rps_client(file)); if (ret) goto err; ret = i915_gem_object_pin_pages(obj); if (ret) goto err; ret = -EFAULT; /* We can only do the GTT pwrite on untiled buffers, as otherwise * it would end up going through the fenced access, and we'll get * different detiling behavior between reading and writing. * pread/pwrite currently are reading and writing from the CPU * perspective, requiring manual detiling by the client. */ if (!i915_gem_object_has_struct_page(obj) || cpu_write_needs_clflush(obj)) /* Note that the gtt paths might fail with non-page-backed user * pointers (e.g. gtt mappings when moving data between * textures). Fallback to the shmem path in that case. */ ret = i915_gem_gtt_pwrite_fast(obj, args); if (ret == -EFAULT || ret == -ENOSPC) { if (obj->phys_handle) ret = i915_gem_phys_pwrite(obj, args, file); else ret = i915_gem_shmem_pwrite(obj, args); } i915_gem_object_unpin_pages(obj); err: i915_gem_object_put(obj); return ret; } static void i915_gem_object_bump_inactive_ggtt(struct drm_i915_gem_object *obj) { struct drm_i915_private *i915; struct list_head *list; struct i915_vma *vma; list_for_each_entry(vma, &obj->vma_list, obj_link) { if (!i915_vma_is_ggtt(vma)) break; if (i915_vma_is_active(vma)) continue; if (!drm_mm_node_allocated(&vma->node)) continue; list_move_tail(&vma->vm_link, &vma->vm->inactive_list); } i915 = to_i915(obj->base.dev); list = obj->bind_count ? &i915->mm.bound_list : &i915->mm.unbound_list; list_move_tail(&obj->global_link, list); } /** * Called when user space prepares to use an object with the CPU, either * through the mmap ioctl's mapping or a GTT mapping. * @dev: drm device * @data: ioctl data blob * @file: drm file */ int i915_gem_set_domain_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_set_domain *args = data; struct drm_i915_gem_object *obj; uint32_t read_domains = args->read_domains; uint32_t write_domain = args->write_domain; int err; /* Only handle setting domains to types used by the CPU. */ if ((write_domain | read_domains) & I915_GEM_GPU_DOMAINS) return -EINVAL; /* Having something in the write domain implies it's in the read * domain, and only that read domain. Enforce that in the request. */ if (write_domain != 0 && read_domains != write_domain) return -EINVAL; obj = i915_gem_object_lookup(file, args->handle); if (!obj) return -ENOENT; /* Try to flush the object off the GPU without holding the lock. * We will repeat the flush holding the lock in the normal manner * to catch cases where we are gazumped. */ err = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | (write_domain ? I915_WAIT_ALL : 0), MAX_SCHEDULE_TIMEOUT, to_rps_client(file)); if (err) goto out; /* Flush and acquire obj->pages so that we are coherent through * direct access in memory with previous cached writes through * shmemfs and that our cache domain tracking remains valid. * For example, if the obj->filp was moved to swap without us * being notified and releasing the pages, we would mistakenly * continue to assume that the obj remained out of the CPU cached * domain. */ err = i915_gem_object_pin_pages(obj); if (err) goto out; err = i915_mutex_lock_interruptible(dev); if (err) goto out_unpin; if (read_domains & I915_GEM_DOMAIN_WC) err = i915_gem_object_set_to_wc_domain(obj, write_domain); else if (read_domains & I915_GEM_DOMAIN_GTT) err = i915_gem_object_set_to_gtt_domain(obj, write_domain); else err = i915_gem_object_set_to_cpu_domain(obj, write_domain); /* And bump the LRU for this access */ i915_gem_object_bump_inactive_ggtt(obj); mutex_unlock(&dev->struct_mutex); if (write_domain != 0) intel_fb_obj_invalidate(obj, fb_write_origin(obj, write_domain)); out_unpin: i915_gem_object_unpin_pages(obj); out: i915_gem_object_put(obj); return err; } /** * Called when user space has done writes to this buffer * @dev: drm device * @data: ioctl data blob * @file: drm file */ int i915_gem_sw_finish_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_sw_finish *args = data; struct drm_i915_gem_object *obj; obj = i915_gem_object_lookup(file, args->handle); if (!obj) return -ENOENT; /* Pinned buffers may be scanout, so flush the cache */ i915_gem_object_flush_if_display(obj); i915_gem_object_put(obj); return 0; } /** * i915_gem_mmap_ioctl - Maps the contents of an object, returning the address * it is mapped to. * @dev: drm device * @data: ioctl data blob * @file: drm file * * While the mapping holds a reference on the contents of the object, it doesn't * imply a ref on the object itself. * * IMPORTANT: * * DRM driver writers who look a this function as an example for how to do GEM * mmap support, please don't implement mmap support like here. The modern way * to implement DRM mmap support is with an mmap offset ioctl (like * i915_gem_mmap_gtt) and then using the mmap syscall on the DRM fd directly. * That way debug tooling like valgrind will understand what's going on, hiding * the mmap call in a driver private ioctl will break that. The i915 driver only * does cpu mmaps this way because we didn't know better. */ int i915_gem_mmap_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_mmap *args = data; struct drm_i915_gem_object *obj; unsigned long addr; if (args->flags & ~(I915_MMAP_WC)) return -EINVAL; if (args->flags & I915_MMAP_WC && !boot_cpu_has(X86_FEATURE_PAT)) return -ENODEV; obj = i915_gem_object_lookup(file, args->handle); if (!obj) return -ENOENT; /* prime objects have no backing filp to GEM mmap * pages from. */ if (!obj->base.filp) { i915_gem_object_put(obj); return -EINVAL; } addr = vm_mmap(obj->base.filp, 0, args->size, PROT_READ | PROT_WRITE, MAP_SHARED, args->offset); if (args->flags & I915_MMAP_WC) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; if (down_write_killable(&mm->mmap_sem)) { i915_gem_object_put(obj); return -EINTR; } vma = find_vma(mm, addr); if (vma) vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); else addr = -ENOMEM; up_write(&mm->mmap_sem); /* This may race, but that's ok, it only gets set */ WRITE_ONCE(obj->frontbuffer_ggtt_origin, ORIGIN_CPU); } i915_gem_object_put(obj); if (IS_ERR((void *)addr)) return addr; args->addr_ptr = (uint64_t) addr; return 0; } static unsigned int tile_row_pages(struct drm_i915_gem_object *obj) { return i915_gem_object_get_tile_row_size(obj) >> PAGE_SHIFT; } /** * i915_gem_mmap_gtt_version - report the current feature set for GTT mmaps * * A history of the GTT mmap interface: * * 0 - Everything had to fit into the GTT. Both parties of a memcpy had to * aligned and suitable for fencing, and still fit into the available * mappable space left by the pinned display objects. A classic problem * we called the page-fault-of-doom where we would ping-pong between * two objects that could not fit inside the GTT and so the memcpy * would page one object in at the expense of the other between every * single byte. * * 1 - Objects can be any size, and have any compatible fencing (X Y, or none * as set via i915_gem_set_tiling() [DRM_I915_GEM_SET_TILING]). If the * object is too large for the available space (or simply too large * for the mappable aperture!), a view is created instead and faulted * into userspace. (This view is aligned and sized appropriately for * fenced access.) * * 2 - Recognise WC as a separate cache domain so that we can flush the * delayed writes via GTT before performing direct access via WC. * * Restrictions: * * * snoopable objects cannot be accessed via the GTT. It can cause machine * hangs on some architectures, corruption on others. An attempt to service * a GTT page fault from a snoopable object will generate a SIGBUS. * * * the object must be able to fit into RAM (physical memory, though no * limited to the mappable aperture). * * * Caveats: * * * a new GTT page fault will synchronize rendering from the GPU and flush * all data to system memory. Subsequent access will not be synchronized. * * * all mappings are revoked on runtime device suspend. * * * there are only 8, 16 or 32 fence registers to share between all users * (older machines require fence register for display and blitter access * as well). Contention of the fence registers will cause the previous users * to be unmapped and any new access will generate new page faults. * * * running out of memory while servicing a fault may generate a SIGBUS, * rather than the expected SIGSEGV. */ int i915_gem_mmap_gtt_version(void) { return 2; } static inline struct i915_ggtt_view compute_partial_view(struct drm_i915_gem_object *obj, pgoff_t page_offset, unsigned int chunk) { struct i915_ggtt_view view; if (i915_gem_object_is_tiled(obj)) chunk = roundup(chunk, tile_row_pages(obj)); view.type = I915_GGTT_VIEW_PARTIAL; view.partial.offset = rounddown(page_offset, chunk); view.partial.size = min_t(unsigned int, chunk, (obj->base.size >> PAGE_SHIFT) - view.partial.offset); /* If the partial covers the entire object, just create a normal VMA. */ if (chunk >= obj->base.size >> PAGE_SHIFT) view.type = I915_GGTT_VIEW_NORMAL; return view; } /** * i915_gem_fault - fault a page into the GTT * @vmf: fault info * * The fault handler is set up by drm_gem_mmap() when a object is GTT mapped * from userspace. The fault handler takes care of binding the object to * the GTT (if needed), allocating and programming a fence register (again, * only if needed based on whether the old reg is still valid or the object * is tiled) and inserting a new PTE into the faulting process. * * Note that the faulting process may involve evicting existing objects * from the GTT and/or fence registers to make room. So performance may * suffer if the GTT working set is large or there are few fence registers * left. * * The current feature set supported by i915_gem_fault() and thus GTT mmaps * is exposed via I915_PARAM_MMAP_GTT_VERSION (see i915_gem_mmap_gtt_version). */ int i915_gem_fault(struct vm_fault *vmf) { #define MIN_CHUNK_PAGES ((1 << 20) >> PAGE_SHIFT) /* 1 MiB */ struct vm_area_struct *area = vmf->vma; struct drm_i915_gem_object *obj = to_intel_bo(area->vm_private_data); struct drm_device *dev = obj->base.dev; struct drm_i915_private *dev_priv = to_i915(dev); struct i915_ggtt *ggtt = &dev_priv->ggtt; bool write = !!(vmf->flags & FAULT_FLAG_WRITE); struct i915_vma *vma; pgoff_t page_offset; unsigned int flags; int ret; /* We don't use vmf->pgoff since that has the fake offset */ page_offset = (vmf->address - area->vm_start) >> PAGE_SHIFT; trace_i915_gem_object_fault(obj, page_offset, true, write); /* Try to flush the object off the GPU first without holding the lock. * Upon acquiring the lock, we will perform our sanity checks and then * repeat the flush holding the lock in the normal manner to catch cases * where we are gazumped. */ ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT, NULL); if (ret) goto err; ret = i915_gem_object_pin_pages(obj); if (ret) goto err; intel_runtime_pm_get(dev_priv); ret = i915_mutex_lock_interruptible(dev); if (ret) goto err_rpm; /* Access to snoopable pages through the GTT is incoherent. */ if (obj->cache_level != I915_CACHE_NONE && !HAS_LLC(dev_priv)) { ret = -EFAULT; goto err_unlock; } /* If the object is smaller than a couple of partial vma, it is * not worth only creating a single partial vma - we may as well * clear enough space for the full object. */ flags = PIN_MAPPABLE; if (obj->base.size > 2 * MIN_CHUNK_PAGES << PAGE_SHIFT) flags |= PIN_NONBLOCK | PIN_NONFAULT; /* Now pin it into the GTT as needed */ vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, flags); if (IS_ERR(vma)) { /* Use a partial view if it is bigger than available space */ struct i915_ggtt_view view = compute_partial_view(obj, page_offset, MIN_CHUNK_PAGES); /* Userspace is now writing through an untracked VMA, abandon * all hope that the hardware is able to track future writes. */ obj->frontbuffer_ggtt_origin = ORIGIN_CPU; vma = i915_gem_object_ggtt_pin(obj, &view, 0, 0, PIN_MAPPABLE); } if (IS_ERR(vma)) { ret = PTR_ERR(vma); goto err_unlock; } ret = i915_gem_object_set_to_gtt_domain(obj, write); if (ret) goto err_unpin; ret = i915_vma_pin_fence(vma); if (ret) goto err_unpin; /* Finally, remap it using the new GTT offset */ ret = remap_io_mapping(area, area->vm_start + (vma->ggtt_view.partial.offset << PAGE_SHIFT), (ggtt->mappable_base + vma->node.start) >> PAGE_SHIFT, min_t(u64, vma->size, area->vm_end - area->vm_start), &ggtt->mappable); if (ret) goto err_fence; /* Mark as being mmapped into userspace for later revocation */ assert_rpm_wakelock_held(dev_priv); if (!i915_vma_set_userfault(vma) && !obj->userfault_count++) list_add(&obj->userfault_link, &dev_priv->mm.userfault_list); GEM_BUG_ON(!obj->userfault_count); err_fence: i915_vma_unpin_fence(vma); err_unpin: __i915_vma_unpin(vma); err_unlock: mutex_unlock(&dev->struct_mutex); err_rpm: intel_runtime_pm_put(dev_priv); i915_gem_object_unpin_pages(obj); err: switch (ret) { case -EIO: /* * We eat errors when the gpu is terminally wedged to avoid * userspace unduly crashing (gl has no provisions for mmaps to * fail). But any other -EIO isn't ours (e.g. swap in failure) * and so needs to be reported. */ if (!i915_terminally_wedged(&dev_priv->gpu_error)) { ret = VM_FAULT_SIGBUS; break; } case -EAGAIN: /* * EAGAIN means the gpu is hung and we'll wait for the error * handler to reset everything when re-faulting in * i915_mutex_lock_interruptible. */ case 0: case -ERESTARTSYS: case -EINTR: case -EBUSY: /* * EBUSY is ok: this just means that another thread * already did the job. */ ret = VM_FAULT_NOPAGE; break; case -ENOMEM: ret = VM_FAULT_OOM; break; case -ENOSPC: case -EFAULT: ret = VM_FAULT_SIGBUS; break; default: WARN_ONCE(ret, "unhandled error in i915_gem_fault: %i\n", ret); ret = VM_FAULT_SIGBUS; break; } return ret; } static void __i915_gem_object_release_mmap(struct drm_i915_gem_object *obj) { struct i915_vma *vma; GEM_BUG_ON(!obj->userfault_count); obj->userfault_count = 0; list_del(&obj->userfault_link); drm_vma_node_unmap(&obj->base.vma_node, obj->base.dev->anon_inode->i_mapping); list_for_each_entry(vma, &obj->vma_list, obj_link) { if (!i915_vma_is_ggtt(vma)) break; i915_vma_unset_userfault(vma); } } /** * i915_gem_release_mmap - remove physical page mappings * @obj: obj in question * * Preserve the reservation of the mmapping with the DRM core code, but * relinquish ownership of the pages back to the system. * * It is vital that we remove the page mapping if we have mapped a tiled * object through the GTT and then lose the fence register due to * resource pressure. Similarly if the object has been moved out of the * aperture, than pages mapped into userspace must be revoked. Removing the * mapping will then trigger a page fault on the next user access, allowing * fixup by i915_gem_fault(). */ void i915_gem_release_mmap(struct drm_i915_gem_object *obj) { struct drm_i915_private *i915 = to_i915(obj->base.dev); /* Serialisation between user GTT access and our code depends upon * revoking the CPU's PTE whilst the mutex is held. The next user * pagefault then has to wait until we release the mutex. * * Note that RPM complicates somewhat by adding an additional * requirement that operations to the GGTT be made holding the RPM * wakeref. */ lockdep_assert_held(&i915->drm.struct_mutex); intel_runtime_pm_get(i915); if (!obj->userfault_count) goto out; __i915_gem_object_release_mmap(obj); /* Ensure that the CPU's PTE are revoked and there are not outstanding * memory transactions from userspace before we return. The TLB * flushing implied above by changing the PTE above *should* be * sufficient, an extra barrier here just provides us with a bit * of paranoid documentation about our requirement to serialise * memory writes before touching registers / GSM. */ wmb(); out: intel_runtime_pm_put(i915); } void i915_gem_runtime_suspend(struct drm_i915_private *dev_priv) { struct drm_i915_gem_object *obj, *on; int i; /* * Only called during RPM suspend. All users of the userfault_list * must be holding an RPM wakeref to ensure that this can not * run concurrently with themselves (and use the struct_mutex for * protection between themselves). */ list_for_each_entry_safe(obj, on, &dev_priv->mm.userfault_list, userfault_link) __i915_gem_object_release_mmap(obj); /* The fence will be lost when the device powers down. If any were * in use by hardware (i.e. they are pinned), we should not be powering * down! All other fences will be reacquired by the user upon waking. */ for (i = 0; i < dev_priv->num_fence_regs; i++) { struct drm_i915_fence_reg *reg = &dev_priv->fence_regs[i]; /* Ideally we want to assert that the fence register is not * live at this point (i.e. that no piece of code will be * trying to write through fence + GTT, as that both violates * our tracking of activity and associated locking/barriers, * but also is illegal given that the hw is powered down). * * Previously we used reg->pin_count as a "liveness" indicator. * That is not sufficient, and we need a more fine-grained * tool if we want to have a sanity check here. */ if (!reg->vma) continue; GEM_BUG_ON(i915_vma_has_userfault(reg->vma)); reg->dirty = true; } } static int i915_gem_object_create_mmap_offset(struct drm_i915_gem_object *obj) { struct drm_i915_private *dev_priv = to_i915(obj->base.dev); int err; err = drm_gem_create_mmap_offset(&obj->base); if (likely(!err)) return 0; /* Attempt to reap some mmap space from dead objects */ do { err = i915_gem_wait_for_idle(dev_priv, I915_WAIT_INTERRUPTIBLE); if (err) break; i915_gem_drain_freed_objects(dev_priv); err = drm_gem_create_mmap_offset(&obj->base); if (!err) break; } while (flush_delayed_work(&dev_priv->gt.retire_work)); return err; } static void i915_gem_object_free_mmap_offset(struct drm_i915_gem_object *obj) { drm_gem_free_mmap_offset(&obj->base); } int i915_gem_mmap_gtt(struct drm_file *file, struct drm_device *dev, uint32_t handle, uint64_t *offset) { struct drm_i915_gem_object *obj; int ret; obj = i915_gem_object_lookup(file, handle); if (!obj) return -ENOENT; ret = i915_gem_object_create_mmap_offset(obj); if (ret == 0) *offset = drm_vma_node_offset_addr(&obj->base.vma_node); i915_gem_object_put(obj); return ret; } /** * i915_gem_mmap_gtt_ioctl - prepare an object for GTT mmap'ing * @dev: DRM device * @data: GTT mapping ioctl data * @file: GEM object info * * Simply returns the fake offset to userspace so it can mmap it. * The mmap call will end up in drm_gem_mmap(), which will set things * up so we can get faults in the handler above. * * The fault handler will take care of binding the object into the GTT * (since it may have been evicted to make room for something), allocating * a fence register, and mapping the appropriate aperture address into * userspace. */ int i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_mmap_gtt *args = data; return i915_gem_mmap_gtt(file, dev, args->handle, &args->offset); } /* Immediately discard the backing storage */ static void i915_gem_object_truncate(struct drm_i915_gem_object *obj) { i915_gem_object_free_mmap_offset(obj); if (obj->base.filp == NULL) return; /* Our goal here is to return as much of the memory as * is possible back to the system as we are called from OOM. * To do this we must instruct the shmfs to drop all of its * backing pages, *now*. */ shmem_truncate_range(file_inode(obj->base.filp), 0, (loff_t)-1); obj->mm.madv = __I915_MADV_PURGED; obj->mm.pages = ERR_PTR(-EFAULT); } /* Try to discard unwanted pages */ void __i915_gem_object_invalidate(struct drm_i915_gem_object *obj) { struct address_space *mapping; lockdep_assert_held(&obj->mm.lock); GEM_BUG_ON(obj->mm.pages); switch (obj->mm.madv) { case I915_MADV_DONTNEED: i915_gem_object_truncate(obj); case __I915_MADV_PURGED: return; } if (obj->base.filp == NULL) return; mapping = obj->base.filp->f_mapping, invalidate_mapping_pages(mapping, 0, (loff_t)-1); } static void i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj, struct sg_table *pages) { struct sgt_iter sgt_iter; struct page *page; __i915_gem_object_release_shmem(obj, pages, true); i915_gem_gtt_finish_pages(obj, pages); if (i915_gem_object_needs_bit17_swizzle(obj)) i915_gem_object_save_bit_17_swizzle(obj, pages); for_each_sgt_page(page, sgt_iter, pages) { if (obj->mm.dirty) set_page_dirty(page); if (obj->mm.madv == I915_MADV_WILLNEED) mark_page_accessed(page); put_page(page); } obj->mm.dirty = false; sg_free_table(pages); kfree(pages); } static void __i915_gem_object_reset_page_iter(struct drm_i915_gem_object *obj) { struct radix_tree_iter iter; void __rcu **slot; radix_tree_for_each_slot(slot, &obj->mm.get_page.radix, &iter, 0) radix_tree_delete(&obj->mm.get_page.radix, iter.index); } void __i915_gem_object_put_pages(struct drm_i915_gem_object *obj, enum i915_mm_subclass subclass) { struct sg_table *pages; if (i915_gem_object_has_pinned_pages(obj)) return; GEM_BUG_ON(obj->bind_count); if (!READ_ONCE(obj->mm.pages)) return; /* May be called by shrinker from within get_pages() (on another bo) */ mutex_lock_nested(&obj->mm.lock, subclass); if (unlikely(atomic_read(&obj->mm.pages_pin_count))) goto unlock; /* ->put_pages might need to allocate memory for the bit17 swizzle * array, hence protect them from being reaped by removing them from gtt * lists early. */ pages = fetch_and_zero(&obj->mm.pages); GEM_BUG_ON(!pages); if (obj->mm.mapping) { void *ptr; ptr = page_mask_bits(obj->mm.mapping); if (is_vmalloc_addr(ptr)) vunmap(ptr); else kunmap(kmap_to_page(ptr)); obj->mm.mapping = NULL; } __i915_gem_object_reset_page_iter(obj); if (!IS_ERR(pages)) obj->ops->put_pages(obj, pages); obj->mm.page_sizes.phys = obj->mm.page_sizes.sg = 0; unlock: mutex_unlock(&obj->mm.lock); } static bool i915_sg_trim(struct sg_table *orig_st) { struct sg_table new_st; struct scatterlist *sg, *new_sg; unsigned int i; if (orig_st->nents == orig_st->orig_nents) return false; if (sg_alloc_table(&new_st, orig_st->nents, GFP_KERNEL | __GFP_NOWARN)) return false; new_sg = new_st.sgl; for_each_sg(orig_st->sgl, sg, orig_st->nents, i) { sg_set_page(new_sg, sg_page(sg), sg->length, 0); /* called before being DMA mapped, no need to copy sg->dma_* */ new_sg = sg_next(new_sg); } GEM_BUG_ON(new_sg); /* Should walk exactly nents and hit the end */ sg_free_table(orig_st); *orig_st = new_st; return true; } static int i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj) { struct drm_i915_private *dev_priv = to_i915(obj->base.dev); const unsigned long page_count = obj->base.size / PAGE_SIZE; unsigned long i; struct address_space *mapping; struct sg_table *st; struct scatterlist *sg; struct sgt_iter sgt_iter; struct page *page; unsigned long last_pfn = 0; /* suppress gcc warning */ unsigned int max_segment = i915_sg_segment_size(); unsigned int sg_page_sizes; gfp_t noreclaim; int ret; /* Assert that the object is not currently in any GPU domain. As it * wasn't in the GTT, there shouldn't be any way it could have been in * a GPU cache */ GEM_BUG_ON(obj->base.read_domains & I915_GEM_GPU_DOMAINS); GEM_BUG_ON(obj->base.write_domain & I915_GEM_GPU_DOMAINS); st = kmalloc(sizeof(*st), GFP_KERNEL); if (st == NULL) return -ENOMEM; rebuild_st: if (sg_alloc_table(st, page_count, GFP_KERNEL)) { kfree(st); return -ENOMEM; } /* Get the list of pages out of our struct file. They'll be pinned * at this point until we release them. * * Fail silently without starting the shrinker */ mapping = obj->base.filp->f_mapping; noreclaim = mapping_gfp_constraint(mapping, ~__GFP_RECLAIM); noreclaim |= __GFP_NORETRY | __GFP_NOWARN; sg = st->sgl; st->nents = 0; sg_page_sizes = 0; for (i = 0; i < page_count; i++) { const unsigned int shrink[] = { I915_SHRINK_BOUND | I915_SHRINK_UNBOUND | I915_SHRINK_PURGEABLE, 0, }, *s = shrink; gfp_t gfp = noreclaim; do { page = shmem_read_mapping_page_gfp(mapping, i, gfp); if (likely(!IS_ERR(page))) break; if (!*s) { ret = PTR_ERR(page); goto err_sg; } i915_gem_shrink(dev_priv, 2 * page_count, NULL, *s++); cond_resched(); /* We've tried hard to allocate the memory by reaping * our own buffer, now let the real VM do its job and * go down in flames if truly OOM. * * However, since graphics tend to be disposable, * defer the oom here by reporting the ENOMEM back * to userspace. */ if (!*s) { /* reclaim and warn, but no oom */ gfp = mapping_gfp_mask(mapping); /* Our bo are always dirty and so we require * kswapd to reclaim our pages (direct reclaim * does not effectively begin pageout of our * buffers on its own). However, direct reclaim * only waits for kswapd when under allocation * congestion. So as a result __GFP_RECLAIM is * unreliable and fails to actually reclaim our * dirty pages -- unless you try over and over * again with !__GFP_NORETRY. However, we still * want to fail this allocation rather than * trigger the out-of-memory killer and for * this we want __GFP_RETRY_MAYFAIL. */ gfp |= __GFP_RETRY_MAYFAIL; } } while (1); if (!i || sg->length >= max_segment || page_to_pfn(page) != last_pfn + 1) { if (i) { sg_page_sizes |= sg->length; sg = sg_next(sg); } st->nents++; sg_set_page(sg, page, PAGE_SIZE, 0); } else { sg->length += PAGE_SIZE; } last_pfn = page_to_pfn(page); /* Check that the i965g/gm workaround works. */ WARN_ON((gfp & __GFP_DMA32) && (last_pfn >= 0x00100000UL)); } if (sg) { /* loop terminated early; short sg table */ sg_page_sizes |= sg->length; sg_mark_end(sg); } /* Trim unused sg entries to avoid wasting memory. */ i915_sg_trim(st); ret = i915_gem_gtt_prepare_pages(obj, st); if (ret) { /* DMA remapping failed? One possible cause is that * it could not reserve enough large entries, asking * for PAGE_SIZE chunks instead may be helpful. */ if (max_segment > PAGE_SIZE) { for_each_sgt_page(page, sgt_iter, st) put_page(page); sg_free_table(st); max_segment = PAGE_SIZE; goto rebuild_st; } else { dev_warn(&dev_priv->drm.pdev->dev, "Failed to DMA remap %lu pages\n", page_count); goto err_pages; } } if (i915_gem_object_needs_bit17_swizzle(obj)) i915_gem_object_do_bit_17_swizzle(obj, st); __i915_gem_object_set_pages(obj, st, sg_page_sizes); return 0; err_sg: sg_mark_end(sg); err_pages: for_each_sgt_page(page, sgt_iter, st) put_page(page); sg_free_table(st); kfree(st); /* shmemfs first checks if there is enough memory to allocate the page * and reports ENOSPC should there be insufficient, along with the usual * ENOMEM for a genuine allocation failure. * * We use ENOSPC in our driver to mean that we have run out of aperture * space and so want to translate the error from shmemfs back to our * usual understanding of ENOMEM. */ if (ret == -ENOSPC) ret = -ENOMEM; return ret; } void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj, struct sg_table *pages, unsigned int sg_page_sizes) { struct drm_i915_private *i915 = to_i915(obj->base.dev); unsigned long supported = INTEL_INFO(i915)->page_sizes; int i; lockdep_assert_held(&obj->mm.lock); obj->mm.get_page.sg_pos = pages->sgl; obj->mm.get_page.sg_idx = 0; obj->mm.pages = pages; if (i915_gem_object_is_tiled(obj) && to_i915(obj->base.dev)->quirks & QUIRK_PIN_SWIZZLED_PAGES) { GEM_BUG_ON(obj->mm.quirked); __i915_gem_object_pin_pages(obj); obj->mm.quirked = true; } GEM_BUG_ON(!sg_page_sizes); obj->mm.page_sizes.phys = sg_page_sizes; /* * Calculate the supported page-sizes which fit into the given * sg_page_sizes. This will give us the page-sizes which we may be able * to use opportunistically when later inserting into the GTT. For * example if phys=2G, then in theory we should be able to use 1G, 2M, * 64K or 4K pages, although in practice this will depend on a number of * other factors. */ obj->mm.page_sizes.sg = 0; for_each_set_bit(i, &supported, ilog2(I915_GTT_MAX_PAGE_SIZE) + 1) { if (obj->mm.page_sizes.phys & ~0u << i) obj->mm.page_sizes.sg |= BIT(i); } GEM_BUG_ON(!HAS_PAGE_SIZES(i915, obj->mm.page_sizes.sg)); } static int ____i915_gem_object_get_pages(struct drm_i915_gem_object *obj) { int err; if (unlikely(obj->mm.madv != I915_MADV_WILLNEED)) { DRM_DEBUG("Attempting to obtain a purgeable object\n"); return -EFAULT; } err = obj->ops->get_pages(obj); GEM_BUG_ON(!err && IS_ERR_OR_NULL(obj->mm.pages)); return err; } /* Ensure that the associated pages are gathered from the backing storage * and pinned into our object. i915_gem_object_pin_pages() may be called * multiple times before they are released by a single call to * i915_gem_object_unpin_pages() - once the pages are no longer referenced * either as a result of memory pressure (reaping pages under the shrinker) * or as the object is itself released. */ int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj) { int err; err = mutex_lock_interruptible(&obj->mm.lock); if (err) return err; if (unlikely(IS_ERR_OR_NULL(obj->mm.pages))) { GEM_BUG_ON(i915_gem_object_has_pinned_pages(obj)); err = ____i915_gem_object_get_pages(obj); if (err) goto unlock; smp_mb__before_atomic(); } atomic_inc(&obj->mm.pages_pin_count); unlock: mutex_unlock(&obj->mm.lock); return err; } /* The 'mapping' part of i915_gem_object_pin_map() below */ static void *i915_gem_object_map(const struct drm_i915_gem_object *obj, enum i915_map_type type) { unsigned long n_pages = obj->base.size >> PAGE_SHIFT; struct sg_table *sgt = obj->mm.pages; struct sgt_iter sgt_iter; struct page *page; struct page *stack_pages[32]; struct page **pages = stack_pages; unsigned long i = 0; pgprot_t pgprot; void *addr; /* A single page can always be kmapped */ if (n_pages == 1 && type == I915_MAP_WB) return kmap(sg_page(sgt->sgl)); if (n_pages > ARRAY_SIZE(stack_pages)) { /* Too big for stack -- allocate temporary array instead */ pages = kvmalloc_array(n_pages, sizeof(*pages), GFP_KERNEL); if (!pages) return NULL; } for_each_sgt_page(page, sgt_iter, sgt) pages[i++] = page; /* Check that we have the expected number of pages */ GEM_BUG_ON(i != n_pages); switch (type) { default: MISSING_CASE(type); /* fallthrough to use PAGE_KERNEL anyway */ case I915_MAP_WB: pgprot = PAGE_KERNEL; break; case I915_MAP_WC: pgprot = pgprot_writecombine(PAGE_KERNEL_IO); break; } addr = vmap(pages, n_pages, 0, pgprot); if (pages != stack_pages) kvfree(pages); return addr; } /* get, pin, and map the pages of the object into kernel space */ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj, enum i915_map_type type) { enum i915_map_type has_type; bool pinned; void *ptr; int ret; GEM_BUG_ON(!i915_gem_object_has_struct_page(obj)); ret = mutex_lock_interruptible(&obj->mm.lock); if (ret) return ERR_PTR(ret); pinned = !(type & I915_MAP_OVERRIDE); type &= ~I915_MAP_OVERRIDE; if (!atomic_inc_not_zero(&obj->mm.pages_pin_count)) { if (unlikely(IS_ERR_OR_NULL(obj->mm.pages))) { GEM_BUG_ON(i915_gem_object_has_pinned_pages(obj)); ret = ____i915_gem_object_get_pages(obj); if (ret) goto err_unlock; smp_mb__before_atomic(); } atomic_inc(&obj->mm.pages_pin_count); pinned = false; } GEM_BUG_ON(!obj->mm.pages); ptr = page_unpack_bits(obj->mm.mapping, &has_type); if (ptr && has_type != type) { if (pinned) { ret = -EBUSY; goto err_unpin; } if (is_vmalloc_addr(ptr)) vunmap(ptr); else kunmap(kmap_to_page(ptr)); ptr = obj->mm.mapping = NULL; } if (!ptr) { ptr = i915_gem_object_map(obj, type); if (!ptr) { ret = -ENOMEM; goto err_unpin; } obj->mm.mapping = page_pack_bits(ptr, type); } out_unlock: mutex_unlock(&obj->mm.lock); return ptr; err_unpin: atomic_dec(&obj->mm.pages_pin_count); err_unlock: ptr = ERR_PTR(ret); goto out_unlock; } static int i915_gem_object_pwrite_gtt(struct drm_i915_gem_object *obj, const struct drm_i915_gem_pwrite *arg) { struct address_space *mapping = obj->base.filp->f_mapping; char __user *user_data = u64_to_user_ptr(arg->data_ptr); u64 remain, offset; unsigned int pg; /* Before we instantiate/pin the backing store for our use, we * can prepopulate the shmemfs filp efficiently using a write into * the pagecache. We avoid the penalty of instantiating all the * pages, important if the user is just writing to a few and never * uses the object on the GPU, and using a direct write into shmemfs * allows it to avoid the cost of retrieving a page (either swapin * or clearing-before-use) before it is overwritten. */ if (READ_ONCE(obj->mm.pages)) return -ENODEV; if (obj->mm.madv != I915_MADV_WILLNEED) return -EFAULT; /* Before the pages are instantiated the object is treated as being * in the CPU domain. The pages will be clflushed as required before * use, and we can freely write into the pages directly. If userspace * races pwrite with any other operation; corruption will ensue - * that is userspace's prerogative! */ remain = arg->size; offset = arg->offset; pg = offset_in_page(offset); do { unsigned int len, unwritten; struct page *page; void *data, *vaddr; int err; len = PAGE_SIZE - pg; if (len > remain) len = remain; err = pagecache_write_begin(obj->base.filp, mapping, offset, len, 0, &page, &data); if (err < 0) return err; vaddr = kmap(page); unwritten = copy_from_user(vaddr + pg, user_data, len); kunmap(page); err = pagecache_write_end(obj->base.filp, mapping, offset, len, len - unwritten, page, data); if (err < 0) return err; if (unwritten) return -EFAULT; remain -= len; user_data += len; offset += len; pg = 0; } while (remain); return 0; } static bool ban_context(const struct i915_gem_context *ctx, unsigned int score) { return (i915_gem_context_is_bannable(ctx) && score >= CONTEXT_SCORE_BAN_THRESHOLD); } static void i915_gem_context_mark_guilty(struct i915_gem_context *ctx) { unsigned int score; bool banned; atomic_inc(&ctx->guilty_count); score = atomic_add_return(CONTEXT_SCORE_GUILTY, &ctx->ban_score); banned = ban_context(ctx, score); DRM_DEBUG_DRIVER("context %s marked guilty (score %d) banned? %s\n", ctx->name, score, yesno(banned)); if (!banned) return; i915_gem_context_set_banned(ctx); if (!IS_ERR_OR_NULL(ctx->file_priv)) { atomic_inc(&ctx->file_priv->context_bans); DRM_DEBUG_DRIVER("client %s has had %d context banned\n", ctx->name, atomic_read(&ctx->file_priv->context_bans)); } } static void i915_gem_context_mark_innocent(struct i915_gem_context *ctx) { atomic_inc(&ctx->active_count); } struct drm_i915_gem_request * i915_gem_find_active_request(struct intel_engine_cs *engine) { struct drm_i915_gem_request *request, *active = NULL; unsigned long flags; /* We are called by the error capture and reset at a random * point in time. In particular, note that neither is crucially * ordered with an interrupt. After a hang, the GPU is dead and we * assume that no more writes can happen (we waited long enough for * all writes that were in transaction to be flushed) - adding an * extra delay for a recent interrupt is pointless. Hence, we do * not need an engine->irq_seqno_barrier() before the seqno reads. */ spin_lock_irqsave(&engine->timeline->lock, flags); list_for_each_entry(request, &engine->timeline->requests, link) { if (__i915_gem_request_completed(request, request->global_seqno)) continue; GEM_BUG_ON(request->engine != engine); GEM_BUG_ON(test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &request->fence.flags)); active = request; break; } spin_unlock_irqrestore(&engine->timeline->lock, flags); return active; } static bool engine_stalled(struct intel_engine_cs *engine) { if (!engine->hangcheck.stalled) return false; /* Check for possible seqno movement after hang declaration */ if (engine->hangcheck.seqno != intel_engine_get_seqno(engine)) { DRM_DEBUG_DRIVER("%s pardoned\n", engine->name); return false; } return true; } /* * Ensure irq handler finishes, and not run again. * Also return the active request so that we only search for it once. */ struct drm_i915_gem_request * i915_gem_reset_prepare_engine(struct intel_engine_cs *engine) { struct drm_i915_gem_request *request = NULL; /* * During the reset sequence, we must prevent the engine from * entering RC6. As the context state is undefined until we restart * the engine, if it does enter RC6 during the reset, the state * written to the powercontext is undefined and so we may lose * GPU state upon resume, i.e. fail to restart after a reset. */ intel_uncore_forcewake_get(engine->i915, FORCEWAKE_ALL); /* * Prevent the signaler thread from updating the request * state (by calling dma_fence_signal) as we are processing * the reset. The write from the GPU of the seqno is * asynchronous and the signaler thread may see a different * value to us and declare the request complete, even though * the reset routine have picked that request as the active * (incomplete) request. This conflict is not handled * gracefully! */ kthread_park(engine->breadcrumbs.signaler); /* * Prevent request submission to the hardware until we have * completed the reset in i915_gem_reset_finish(). If a request * is completed by one engine, it may then queue a request * to a second via its engine->irq_tasklet *just* as we are * calling engine->init_hw() and also writing the ELSP. * Turning off the engine->irq_tasklet until the reset is over * prevents the race. */ tasklet_kill(&engine->execlists.irq_tasklet); tasklet_disable(&engine->execlists.irq_tasklet); if (engine->irq_seqno_barrier) engine->irq_seqno_barrier(engine); request = i915_gem_find_active_request(engine); if (request && request->fence.error == -EIO) request = ERR_PTR(-EIO); /* Previous reset failed! */ return request; } int i915_gem_reset_prepare(struct drm_i915_private *dev_priv) { struct intel_engine_cs *engine; struct drm_i915_gem_request *request; enum intel_engine_id id; int err = 0; for_each_engine(engine, dev_priv, id) { request = i915_gem_reset_prepare_engine(engine); if (IS_ERR(request)) { err = PTR_ERR(request); continue; } engine->hangcheck.active_request = request; } i915_gem_revoke_fences(dev_priv); return err; } static void skip_request(struct drm_i915_gem_request *request) { void *vaddr = request->ring->vaddr; u32 head; /* As this request likely depends on state from the lost * context, clear out all the user operations leaving the * breadcrumb at the end (so we get the fence notifications). */ head = request->head; if (request->postfix < head) { memset(vaddr + head, 0, request->ring->size - head); head = 0; } memset(vaddr + head, 0, request->postfix - head); dma_fence_set_error(&request->fence, -EIO); } static void engine_skip_context(struct drm_i915_gem_request *request) { struct intel_engine_cs *engine = request->engine; struct i915_gem_context *hung_ctx = request->ctx; struct intel_timeline *timeline; unsigned long flags; timeline = i915_gem_context_lookup_timeline(hung_ctx, engine); spin_lock_irqsave(&engine->timeline->lock, flags); spin_lock(&timeline->lock); list_for_each_entry_continue(request, &engine->timeline->requests, link) if (request->ctx == hung_ctx) skip_request(request); list_for_each_entry(request, &timeline->requests, link) skip_request(request); spin_unlock(&timeline->lock); spin_unlock_irqrestore(&engine->timeline->lock, flags); } /* Returns the request if it was guilty of the hang */ static struct drm_i915_gem_request * i915_gem_reset_request(struct intel_engine_cs *engine, struct drm_i915_gem_request *request) { /* The guilty request will get skipped on a hung engine. * * Users of client default contexts do not rely on logical * state preserved between batches so it is safe to execute * queued requests following the hang. Non default contexts * rely on preserved state, so skipping a batch loses the * evolution of the state and it needs to be considered corrupted. * Executing more queued batches on top of corrupted state is * risky. But we take the risk by trying to advance through * the queued requests in order to make the client behaviour * more predictable around resets, by not throwing away random * amount of batches it has prepared for execution. Sophisticated * clients can use gem_reset_stats_ioctl and dma fence status * (exported via sync_file info ioctl on explicit fences) to observe * when it loses the context state and should rebuild accordingly. * * The context ban, and ultimately the client ban, mechanism are safety * valves if client submission ends up resulting in nothing more than * subsequent hangs. */ if (engine_stalled(engine)) { i915_gem_context_mark_guilty(request->ctx); skip_request(request); /* If this context is now banned, skip all pending requests. */ if (i915_gem_context_is_banned(request->ctx)) engine_skip_context(request); } else { /* * Since this is not the hung engine, it may have advanced * since the hang declaration. Double check by refinding * the active request at the time of the reset. */ request = i915_gem_find_active_request(engine); if (request) { i915_gem_context_mark_innocent(request->ctx); dma_fence_set_error(&request->fence, -EAGAIN); /* Rewind the engine to replay the incomplete rq */ spin_lock_irq(&engine->timeline->lock); request = list_prev_entry(request, link); if (&request->link == &engine->timeline->requests) request = NULL; spin_unlock_irq(&engine->timeline->lock); } } return request; } void i915_gem_reset_engine(struct intel_engine_cs *engine, struct drm_i915_gem_request *request) { engine->irq_posted = 0; if (request) request = i915_gem_reset_request(engine, request); if (request) { DRM_DEBUG_DRIVER("resetting %s to restart from tail of request 0x%x\n", engine->name, request->global_seqno); } /* Setup the CS to resume from the breadcrumb of the hung request */ engine->reset_hw(engine, request); } void i915_gem_reset(struct drm_i915_private *dev_priv) { struct intel_engine_cs *engine; enum intel_engine_id id; lockdep_assert_held(&dev_priv->drm.struct_mutex); i915_gem_retire_requests(dev_priv); for_each_engine(engine, dev_priv, id) { struct i915_gem_context *ctx; i915_gem_reset_engine(engine, engine->hangcheck.active_request); ctx = fetch_and_zero(&engine->last_retired_context); if (ctx) engine->context_unpin(engine, ctx); } i915_gem_restore_fences(dev_priv); if (dev_priv->gt.awake) { intel_sanitize_gt_powersave(dev_priv); intel_enable_gt_powersave(dev_priv); if (INTEL_GEN(dev_priv) >= 6) gen6_rps_busy(dev_priv); } } void i915_gem_reset_finish_engine(struct intel_engine_cs *engine) { tasklet_enable(&engine->execlists.irq_tasklet); kthread_unpark(engine->breadcrumbs.signaler); intel_uncore_forcewake_put(engine->i915, FORCEWAKE_ALL); } void i915_gem_reset_finish(struct drm_i915_private *dev_priv) { struct intel_engine_cs *engine; enum intel_engine_id id; lockdep_assert_held(&dev_priv->drm.struct_mutex); for_each_engine(engine, dev_priv, id) { engine->hangcheck.active_request = NULL; i915_gem_reset_finish_engine(engine); } } static void nop_submit_request(struct drm_i915_gem_request *request) { GEM_BUG_ON(!i915_terminally_wedged(&request->i915->gpu_error)); dma_fence_set_error(&request->fence, -EIO); i915_gem_request_submit(request); } static void nop_complete_submit_request(struct drm_i915_gem_request *request) { unsigned long flags; GEM_BUG_ON(!i915_terminally_wedged(&request->i915->gpu_error)); dma_fence_set_error(&request->fence, -EIO); spin_lock_irqsave(&request->engine->timeline->lock, flags); __i915_gem_request_submit(request); intel_engine_init_global_seqno(request->engine, request->global_seqno); spin_unlock_irqrestore(&request->engine->timeline->lock, flags); } void i915_gem_set_wedged(struct drm_i915_private *i915) { struct intel_engine_cs *engine; enum intel_engine_id id; /* * First, stop submission to hw, but do not yet complete requests by * rolling the global seqno forward (since this would complete requests * for which we haven't set the fence error to EIO yet). */ for_each_engine(engine, i915, id) engine->submit_request = nop_submit_request; /* * Make sure no one is running the old callback before we proceed with * cancelling requests and resetting the completion tracking. Otherwise * we might submit a request to the hardware which never completes. */ synchronize_rcu(); for_each_engine(engine, i915, id) { /* Mark all executing requests as skipped */ engine->cancel_requests(engine); /* * Only once we've force-cancelled all in-flight requests can we * start to complete all requests. */ engine->submit_request = nop_complete_submit_request; } /* * Make sure no request can slip through without getting completed by * either this call here to intel_engine_init_global_seqno, or the one * in nop_complete_submit_request. */ synchronize_rcu(); for_each_engine(engine, i915, id) { unsigned long flags; /* Mark all pending requests as complete so that any concurrent * (lockless) lookup doesn't try and wait upon the request as we * reset it. */ spin_lock_irqsave(&engine->timeline->lock, flags); intel_engine_init_global_seqno(engine, intel_engine_last_submit(engine)); spin_unlock_irqrestore(&engine->timeline->lock, flags); } set_bit(I915_WEDGED, &i915->gpu_error.flags); wake_up_all(&i915->gpu_error.reset_queue); } bool i915_gem_unset_wedged(struct drm_i915_private *i915) { struct i915_gem_timeline *tl; int i; lockdep_assert_held(&i915->drm.struct_mutex); if (!test_bit(I915_WEDGED, &i915->gpu_error.flags)) return true; /* Before unwedging, make sure that all pending operations * are flushed and errored out - we may have requests waiting upon * third party fences. We marked all inflight requests as EIO, and * every execbuf since returned EIO, for consistency we want all * the currently pending requests to also be marked as EIO, which * is done inside our nop_submit_request - and so we must wait. * * No more can be submitted until we reset the wedged bit. */ list_for_each_entry(tl, &i915->gt.timelines, link) { for (i = 0; i < ARRAY_SIZE(tl->engine); i++) { struct drm_i915_gem_request *rq; rq = i915_gem_active_peek(&tl->engine[i].last_request, &i915->drm.struct_mutex); if (!rq) continue; /* We can't use our normal waiter as we want to * avoid recursively trying to handle the current * reset. The basic dma_fence_default_wait() installs * a callback for dma_fence_signal(), which is * triggered by our nop handler (indirectly, the * callback enables the signaler thread which is * woken by the nop_submit_request() advancing the seqno * and when the seqno passes the fence, the signaler * then signals the fence waking us up). */ if (dma_fence_default_wait(&rq->fence, true, MAX_SCHEDULE_TIMEOUT) < 0) return false; } } /* Undo nop_submit_request. We prevent all new i915 requests from * being queued (by disallowing execbuf whilst wedged) so having * waited for all active requests above, we know the system is idle * and do not have to worry about a thread being inside * engine->submit_request() as we swap over. So unlike installing * the nop_submit_request on reset, we can do this from normal * context and do not require stop_machine(). */ intel_engines_reset_default_submission(i915); i915_gem_contexts_lost(i915); smp_mb__before_atomic(); /* complete takeover before enabling execbuf */ clear_bit(I915_WEDGED, &i915->gpu_error.flags); return true; } static void i915_gem_retire_work_handler(struct work_struct *work) { struct drm_i915_private *dev_priv = container_of(work, typeof(*dev_priv), gt.retire_work.work); struct drm_device *dev = &dev_priv->drm; /* Come back later if the device is busy... */ if (mutex_trylock(&dev->struct_mutex)) { i915_gem_retire_requests(dev_priv); mutex_unlock(&dev->struct_mutex); } /* Keep the retire handler running until we are finally idle. * We do not need to do this test under locking as in the worst-case * we queue the retire worker once too often. */ if (READ_ONCE(dev_priv->gt.awake)) { i915_queue_hangcheck(dev_priv); queue_delayed_work(dev_priv->wq, &dev_priv->gt.retire_work, round_jiffies_up_relative(HZ)); } } static void i915_gem_idle_work_handler(struct work_struct *work) { struct drm_i915_private *dev_priv = container_of(work, typeof(*dev_priv), gt.idle_work.work); struct drm_device *dev = &dev_priv->drm; bool rearm_hangcheck; if (!READ_ONCE(dev_priv->gt.awake)) return; /* * Wait for last execlists context complete, but bail out in case a * new request is submitted. */ wait_for(intel_engines_are_idle(dev_priv), 10); if (READ_ONCE(dev_priv->gt.active_requests)) return; rearm_hangcheck = cancel_delayed_work_sync(&dev_priv->gpu_error.hangcheck_work); if (!mutex_trylock(&dev->struct_mutex)) { /* Currently busy, come back later */ mod_delayed_work(dev_priv->wq, &dev_priv->gt.idle_work, msecs_to_jiffies(50)); goto out_rearm; } /* * New request retired after this work handler started, extend active * period until next instance of the work. */ if (work_pending(work)) goto out_unlock; if (dev_priv->gt.active_requests) goto out_unlock; if (wait_for(intel_engines_are_idle(dev_priv), 10)) DRM_ERROR("Timeout waiting for engines to idle\n"); intel_engines_mark_idle(dev_priv); i915_gem_timelines_mark_idle(dev_priv); GEM_BUG_ON(!dev_priv->gt.awake); dev_priv->gt.awake = false; rearm_hangcheck = false; if (INTEL_GEN(dev_priv) >= 6) gen6_rps_idle(dev_priv); intel_runtime_pm_put(dev_priv); out_unlock: mutex_unlock(&dev->struct_mutex); out_rearm: if (rearm_hangcheck) { GEM_BUG_ON(!dev_priv->gt.awake); i915_queue_hangcheck(dev_priv); } } void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file) { struct drm_i915_private *i915 = to_i915(gem->dev); struct drm_i915_gem_object *obj = to_intel_bo(gem); struct drm_i915_file_private *fpriv = file->driver_priv; struct i915_lut_handle *lut, *ln; mutex_lock(&i915->drm.struct_mutex); list_for_each_entry_safe(lut, ln, &obj->lut_list, obj_link) { struct i915_gem_context *ctx = lut->ctx; struct i915_vma *vma; GEM_BUG_ON(ctx->file_priv == ERR_PTR(-EBADF)); if (ctx->file_priv != fpriv) continue; vma = radix_tree_delete(&ctx->handles_vma, lut->handle); GEM_BUG_ON(vma->obj != obj); /* We allow the process to have multiple handles to the same * vma, in the same fd namespace, by virtue of flink/open. */ GEM_BUG_ON(!vma->open_count); if (!--vma->open_count && !i915_vma_is_ggtt(vma)) i915_vma_close(vma); list_del(&lut->obj_link); list_del(&lut->ctx_link); kmem_cache_free(i915->luts, lut); __i915_gem_object_release_unless_active(obj); } mutex_unlock(&i915->drm.struct_mutex); } static unsigned long to_wait_timeout(s64 timeout_ns) { if (timeout_ns < 0) return MAX_SCHEDULE_TIMEOUT; if (timeout_ns == 0) return 0; return nsecs_to_jiffies_timeout(timeout_ns); } /** * i915_gem_wait_ioctl - implements DRM_IOCTL_I915_GEM_WAIT * @dev: drm device pointer * @data: ioctl data blob * @file: drm file pointer * * Returns 0 if successful, else an error is returned with the remaining time in * the timeout parameter. * -ETIME: object is still busy after timeout * -ERESTARTSYS: signal interrupted the wait * -ENONENT: object doesn't exist * Also possible, but rare: * -EAGAIN: incomplete, restart syscall * -ENOMEM: damn * -ENODEV: Internal IRQ fail * -E?: The add request failed * * The wait ioctl with a timeout of 0 reimplements the busy ioctl. With any * non-zero timeout parameter the wait ioctl will wait for the given number of * nanoseconds on an object becoming unbusy. Since the wait itself does so * without holding struct_mutex the object may become re-busied before this * function completes. A similar but shorter * race condition exists in the busy * ioctl */ int i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_wait *args = data; struct drm_i915_gem_object *obj; ktime_t start; long ret; if (args->flags != 0) return -EINVAL; obj = i915_gem_object_lookup(file, args->bo_handle); if (!obj) return -ENOENT; start = ktime_get(); ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_ALL, to_wait_timeout(args->timeout_ns), to_rps_client(file)); if (args->timeout_ns > 0) { args->timeout_ns -= ktime_to_ns(ktime_sub(ktime_get(), start)); if (args->timeout_ns < 0) args->timeout_ns = 0; /* * Apparently ktime isn't accurate enough and occasionally has a * bit of mismatch in the jiffies<->nsecs<->ktime loop. So patch * things up to make the test happy. We allow up to 1 jiffy. * * This is a regression from the timespec->ktime conversion. */ if (ret == -ETIME && !nsecs_to_jiffies(args->timeout_ns)) args->timeout_ns = 0; /* Asked to wait beyond the jiffie/scheduler precision? */ if (ret == -ETIME && args->timeout_ns) ret = -EAGAIN; } i915_gem_object_put(obj); return ret; } static int wait_for_timeline(struct i915_gem_timeline *tl, unsigned int flags) { int ret, i; for (i = 0; i < ARRAY_SIZE(tl->engine); i++) { ret = i915_gem_active_wait(&tl->engine[i].last_request, flags); if (ret) return ret; } return 0; } static int wait_for_engines(struct drm_i915_private *i915) { if (wait_for(intel_engines_are_idle(i915), 50)) { DRM_ERROR("Failed to idle engines, declaring wedged!\n"); i915_gem_set_wedged(i915); return -EIO; } return 0; } int i915_gem_wait_for_idle(struct drm_i915_private *i915, unsigned int flags) { int ret; /* If the device is asleep, we have no requests outstanding */ if (!READ_ONCE(i915->gt.awake)) return 0; if (flags & I915_WAIT_LOCKED) { struct i915_gem_timeline *tl; lockdep_assert_held(&i915->drm.struct_mutex); list_for_each_entry(tl, &i915->gt.timelines, link) { ret = wait_for_timeline(tl, flags); if (ret) return ret; } i915_gem_retire_requests(i915); GEM_BUG_ON(i915->gt.active_requests); ret = wait_for_engines(i915); } else { ret = wait_for_timeline(&i915->gt.global_timeline, flags); } return ret; } static void __i915_gem_object_flush_for_display(struct drm_i915_gem_object *obj) { /* * We manually flush the CPU domain so that we can override and * force the flush for the display, and perform it asyncrhonously. */ flush_write_domain(obj, ~I915_GEM_DOMAIN_CPU); if (obj->cache_dirty) i915_gem_clflush_object(obj, I915_CLFLUSH_FORCE); obj->base.write_domain = 0; } void i915_gem_object_flush_if_display(struct drm_i915_gem_object *obj) { if (!READ_ONCE(obj->pin_display)) return; mutex_lock(&obj->base.dev->struct_mutex); __i915_gem_object_flush_for_display(obj); mutex_unlock(&obj->base.dev->struct_mutex); } /** * Moves a single object to the WC read, and possibly write domain. * @obj: object to act on * @write: ask for write access or read only * * This function returns when the move is complete, including waiting on * flushes to occur. */ int i915_gem_object_set_to_wc_domain(struct drm_i915_gem_object *obj, bool write) { int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED | (write ? I915_WAIT_ALL : 0), MAX_SCHEDULE_TIMEOUT, NULL); if (ret) return ret; if (obj->base.write_domain == I915_GEM_DOMAIN_WC) return 0; /* Flush and acquire obj->pages so that we are coherent through * direct access in memory with previous cached writes through * shmemfs and that our cache domain tracking remains valid. * For example, if the obj->filp was moved to swap without us * being notified and releasing the pages, we would mistakenly * continue to assume that the obj remained out of the CPU cached * domain. */ ret = i915_gem_object_pin_pages(obj); if (ret) return ret; flush_write_domain(obj, ~I915_GEM_DOMAIN_WC); /* Serialise direct access to this object with the barriers for * coherent writes from the GPU, by effectively invalidating the * WC domain upon first access. */ if ((obj->base.read_domains & I915_GEM_DOMAIN_WC) == 0) mb(); /* It should now be out of any other write domains, and we can update * the domain values for our changes. */ GEM_BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_WC) != 0); obj->base.read_domains |= I915_GEM_DOMAIN_WC; if (write) { obj->base.read_domains = I915_GEM_DOMAIN_WC; obj->base.write_domain = I915_GEM_DOMAIN_WC; obj->mm.dirty = true; } i915_gem_object_unpin_pages(obj); return 0; } /** * Moves a single object to the GTT read, and possibly write domain. * @obj: object to act on * @write: ask for write access or read only * * This function returns when the move is complete, including waiting on * flushes to occur. */ int i915_gem_object_set_to_gtt_domain(struct drm_i915_gem_object *obj, bool write) { int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED | (write ? I915_WAIT_ALL : 0), MAX_SCHEDULE_TIMEOUT, NULL); if (ret) return ret; if (obj->base.write_domain == I915_GEM_DOMAIN_GTT) return 0; /* Flush and acquire obj->pages so that we are coherent through * direct access in memory with previous cached writes through * shmemfs and that our cache domain tracking remains valid. * For example, if the obj->filp was moved to swap without us * being notified and releasing the pages, we would mistakenly * continue to assume that the obj remained out of the CPU cached * domain. */ ret = i915_gem_object_pin_pages(obj); if (ret) return ret; flush_write_domain(obj, ~I915_GEM_DOMAIN_GTT); /* Serialise direct access to this object with the barriers for * coherent writes from the GPU, by effectively invalidating the * GTT domain upon first access. */ if ((obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0) mb(); /* It should now be out of any other write domains, and we can update * the domain values for our changes. */ GEM_BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_GTT) != 0); obj->base.read_domains |= I915_GEM_DOMAIN_GTT; if (write) { obj->base.read_domains = I915_GEM_DOMAIN_GTT; obj->base.write_domain = I915_GEM_DOMAIN_GTT; obj->mm.dirty = true; } i915_gem_object_unpin_pages(obj); return 0; } /** * Changes the cache-level of an object across all VMA. * @obj: object to act on * @cache_level: new cache level to set for the object * * After this function returns, the object will be in the new cache-level * across all GTT and the contents of the backing storage will be coherent, * with respect to the new cache-level. In order to keep the backing storage * coherent for all users, we only allow a single cache level to be set * globally on the object and prevent it from being changed whilst the * hardware is reading from the object. That is if the object is currently * on the scanout it will be set to uncached (or equivalent display * cache coherency) and all non-MOCS GPU access will also be uncached so * that all direct access to the scanout remains coherent. */ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj, enum i915_cache_level cache_level) { struct i915_vma *vma; int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); if (obj->cache_level == cache_level) return 0; /* Inspect the list of currently bound VMA and unbind any that would * be invalid given the new cache-level. This is principally to * catch the issue of the CS prefetch crossing page boundaries and * reading an invalid PTE on older architectures. */ restart: list_for_each_entry(vma, &obj->vma_list, obj_link) { if (!drm_mm_node_allocated(&vma->node)) continue; if (i915_vma_is_pinned(vma)) { DRM_DEBUG("can not change the cache level of pinned objects\n"); return -EBUSY; } if (i915_gem_valid_gtt_space(vma, cache_level)) continue; ret = i915_vma_unbind(vma); if (ret) return ret; /* As unbinding may affect other elements in the * obj->vma_list (due to side-effects from retiring * an active vma), play safe and restart the iterator. */ goto restart; } /* We can reuse the existing drm_mm nodes but need to change the * cache-level on the PTE. We could simply unbind them all and * rebind with the correct cache-level on next use. However since * we already have a valid slot, dma mapping, pages etc, we may as * rewrite the PTE in the belief that doing so tramples upon less * state and so involves less work. */ if (obj->bind_count) { /* Before we change the PTE, the GPU must not be accessing it. * If we wait upon the object, we know that all the bound * VMA are no longer active. */ ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED | I915_WAIT_ALL, MAX_SCHEDULE_TIMEOUT, NULL); if (ret) return ret; if (!HAS_LLC(to_i915(obj->base.dev)) && cache_level != I915_CACHE_NONE) { /* Access to snoopable pages through the GTT is * incoherent and on some machines causes a hard * lockup. Relinquish the CPU mmaping to force * userspace to refault in the pages and we can * then double check if the GTT mapping is still * valid for that pointer access. */ i915_gem_release_mmap(obj); /* As we no longer need a fence for GTT access, * we can relinquish it now (and so prevent having * to steal a fence from someone else on the next * fence request). Note GPU activity would have * dropped the fence as all snoopable access is * supposed to be linear. */ list_for_each_entry(vma, &obj->vma_list, obj_link) { ret = i915_vma_put_fence(vma); if (ret) return ret; } } else { /* We either have incoherent backing store and * so no GTT access or the architecture is fully * coherent. In such cases, existing GTT mmaps * ignore the cache bit in the PTE and we can * rewrite it without confusing the GPU or having * to force userspace to fault back in its mmaps. */ } list_for_each_entry(vma, &obj->vma_list, obj_link) { if (!drm_mm_node_allocated(&vma->node)) continue; ret = i915_vma_bind(vma, cache_level, PIN_UPDATE); if (ret) return ret; } } list_for_each_entry(vma, &obj->vma_list, obj_link) vma->node.color = cache_level; i915_gem_object_set_cache_coherency(obj, cache_level); obj->cache_dirty = true; /* Always invalidate stale cachelines */ return 0; } int i915_gem_get_caching_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_caching *args = data; struct drm_i915_gem_object *obj; int err = 0; rcu_read_lock(); obj = i915_gem_object_lookup_rcu(file, args->handle); if (!obj) { err = -ENOENT; goto out; } switch (obj->cache_level) { case I915_CACHE_LLC: case I915_CACHE_L3_LLC: args->caching = I915_CACHING_CACHED; break; case I915_CACHE_WT: args->caching = I915_CACHING_DISPLAY; break; default: args->caching = I915_CACHING_NONE; break; } out: rcu_read_unlock(); return err; } int i915_gem_set_caching_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_private *i915 = to_i915(dev); struct drm_i915_gem_caching *args = data; struct drm_i915_gem_object *obj; enum i915_cache_level level; int ret = 0; switch (args->caching) { case I915_CACHING_NONE: level = I915_CACHE_NONE; break; case I915_CACHING_CACHED: /* * Due to a HW issue on BXT A stepping, GPU stores via a * snooped mapping may leave stale data in a corresponding CPU * cacheline, whereas normally such cachelines would get * invalidated. */ if (!HAS_LLC(i915) && !HAS_SNOOP(i915)) return -ENODEV; level = I915_CACHE_LLC; break; case I915_CACHING_DISPLAY: level = HAS_WT(i915) ? I915_CACHE_WT : I915_CACHE_NONE; break; default: return -EINVAL; } obj = i915_gem_object_lookup(file, args->handle); if (!obj) return -ENOENT; if (obj->cache_level == level) goto out; ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT, to_rps_client(file)); if (ret) goto out; ret = i915_mutex_lock_interruptible(dev); if (ret) goto out; ret = i915_gem_object_set_cache_level(obj, level); mutex_unlock(&dev->struct_mutex); out: i915_gem_object_put(obj); return ret; } /* * Prepare buffer for display plane (scanout, cursors, etc). * Can be called from an uninterruptible phase (modesetting) and allows * any flushes to be pipelined (for pageflips). */ struct i915_vma * i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj, u32 alignment, const struct i915_ggtt_view *view) { struct i915_vma *vma; int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); /* Mark the pin_display early so that we account for the * display coherency whilst setting up the cache domains. */ obj->pin_display++; /* The display engine is not coherent with the LLC cache on gen6. As * a result, we make sure that the pinning that is about to occur is * done with uncached PTEs. This is lowest common denominator for all * chipsets. * * However for gen6+, we could do better by using the GFDT bit instead * of uncaching, which would allow us to flush all the LLC-cached data * with that bit in the PTE to main memory with just one PIPE_CONTROL. */ ret = i915_gem_object_set_cache_level(obj, HAS_WT(to_i915(obj->base.dev)) ? I915_CACHE_WT : I915_CACHE_NONE); if (ret) { vma = ERR_PTR(ret); goto err_unpin_display; } /* As the user may map the buffer once pinned in the display plane * (e.g. libkms for the bootup splash), we have to ensure that we * always use map_and_fenceable for all scanout buffers. However, * it may simply be too big to fit into mappable, in which case * put it anyway and hope that userspace can cope (but always first * try to preserve the existing ABI). */ vma = ERR_PTR(-ENOSPC); if (!view || view->type == I915_GGTT_VIEW_NORMAL) vma = i915_gem_object_ggtt_pin(obj, view, 0, alignment, PIN_MAPPABLE | PIN_NONBLOCK); if (IS_ERR(vma)) { struct drm_i915_private *i915 = to_i915(obj->base.dev); unsigned int flags; /* Valleyview is definitely limited to scanning out the first * 512MiB. Lets presume this behaviour was inherited from the * g4x display engine and that all earlier gen are similarly * limited. Testing suggests that it is a little more * complicated than this. For example, Cherryview appears quite * happy to scanout from anywhere within its global aperture. */ flags = 0; if (HAS_GMCH_DISPLAY(i915)) flags = PIN_MAPPABLE; vma = i915_gem_object_ggtt_pin(obj, view, 0, alignment, flags); } if (IS_ERR(vma)) goto err_unpin_display; vma->display_alignment = max_t(u64, vma->display_alignment, alignment); /* Treat this as an end-of-frame, like intel_user_framebuffer_dirty() */ __i915_gem_object_flush_for_display(obj); intel_fb_obj_flush(obj, ORIGIN_DIRTYFB); /* It should now be out of any other write domains, and we can update * the domain values for our changes. */ obj->base.read_domains |= I915_GEM_DOMAIN_GTT; return vma; err_unpin_display: obj->pin_display--; return vma; } void i915_gem_object_unpin_from_display_plane(struct i915_vma *vma) { lockdep_assert_held(&vma->vm->i915->drm.struct_mutex); if (WARN_ON(vma->obj->pin_display == 0)) return; if (--vma->obj->pin_display == 0) vma->display_alignment = I915_GTT_MIN_ALIGNMENT; /* Bump the LRU to try and avoid premature eviction whilst flipping */ i915_gem_object_bump_inactive_ggtt(vma->obj); i915_vma_unpin(vma); } /** * Moves a single object to the CPU read, and possibly write domain. * @obj: object to act on * @write: requesting write or read-only access * * This function returns when the move is complete, including waiting on * flushes to occur. */ int i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write) { int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); ret = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED | (write ? I915_WAIT_ALL : 0), MAX_SCHEDULE_TIMEOUT, NULL); if (ret) return ret; flush_write_domain(obj, ~I915_GEM_DOMAIN_CPU); /* Flush the CPU cache if it's still invalid. */ if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0) { i915_gem_clflush_object(obj, I915_CLFLUSH_SYNC); obj->base.read_domains |= I915_GEM_DOMAIN_CPU; } /* It should now be out of any other write domains, and we can update * the domain values for our changes. */ GEM_BUG_ON(obj->base.write_domain & ~I915_GEM_DOMAIN_CPU); /* If we're writing through the CPU, then the GPU read domains will * need to be invalidated at next use. */ if (write) __start_cpu_write(obj); return 0; } /* Throttle our rendering by waiting until the ring has completed our requests * emitted over 20 msec ago. * * Note that if we were to use the current jiffies each time around the loop, * we wouldn't escape the function with any frames outstanding if the time to * render a frame was over 20ms. * * This should get us reasonable parallelism between CPU and GPU but also * relatively low latency when blocking on a particular request to finish. */ static int i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file) { struct drm_i915_private *dev_priv = to_i915(dev); struct drm_i915_file_private *file_priv = file->driver_priv; unsigned long recent_enough = jiffies - DRM_I915_THROTTLE_JIFFIES; struct drm_i915_gem_request *request, *target = NULL; long ret; /* ABI: return -EIO if already wedged */ if (i915_terminally_wedged(&dev_priv->gpu_error)) return -EIO; spin_lock(&file_priv->mm.lock); list_for_each_entry(request, &file_priv->mm.request_list, client_link) { if (time_after_eq(request->emitted_jiffies, recent_enough)) break; if (target) { list_del(&target->client_link); target->file_priv = NULL; } target = request; } if (target) i915_gem_request_get(target); spin_unlock(&file_priv->mm.lock); if (target == NULL) return 0; ret = i915_wait_request(target, I915_WAIT_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); i915_gem_request_put(target); return ret < 0 ? ret : 0; } struct i915_vma * i915_gem_object_ggtt_pin(struct drm_i915_gem_object *obj, const struct i915_ggtt_view *view, u64 size, u64 alignment, u64 flags) { struct drm_i915_private *dev_priv = to_i915(obj->base.dev); struct i915_address_space *vm = &dev_priv->ggtt.base; struct i915_vma *vma; int ret; lockdep_assert_held(&obj->base.dev->struct_mutex); if (!view && flags & PIN_MAPPABLE) { /* If the required space is larger than the available * aperture, we will not able to find a slot for the * object and unbinding the object now will be in * vain. Worse, doing so may cause us to ping-pong * the object in and out of the Global GTT and * waste a lot of cycles under the mutex. */ if (obj->base.size > dev_priv->ggtt.mappable_end) return ERR_PTR(-E2BIG); /* If NONBLOCK is set the caller is optimistically * trying to cache the full object within the mappable * aperture, and *must* have a fallback in place for * situations where we cannot bind the object. We * can be a little more lax here and use the fallback * more often to avoid costly migrations of ourselves * and other objects within the aperture. * * Half-the-aperture is used as a simple heuristic. * More interesting would to do search for a free * block prior to making the commitment to unbind. * That caters for the self-harm case, and with a * little more heuristics (e.g. NOFAULT, NOEVICT) * we could try to minimise harm to others. */ if (flags & PIN_NONBLOCK && obj->base.size > dev_priv->ggtt.mappable_end / 2) return ERR_PTR(-ENOSPC); } vma = i915_vma_instance(obj, vm, view); if (unlikely(IS_ERR(vma))) return vma; if (i915_vma_misplaced(vma, size, alignment, flags)) { if (flags & PIN_NONBLOCK) { if (i915_vma_is_pinned(vma) || i915_vma_is_active(vma)) return ERR_PTR(-ENOSPC); if (flags & PIN_MAPPABLE && vma->fence_size > dev_priv->ggtt.mappable_end / 2) return ERR_PTR(-ENOSPC); } WARN(i915_vma_is_pinned(vma), "bo is already pinned in ggtt with incorrect alignment:" " offset=%08x, req.alignment=%llx," " req.map_and_fenceable=%d, vma->map_and_fenceable=%d\n", i915_ggtt_offset(vma), alignment, !!(flags & PIN_MAPPABLE), i915_vma_is_map_and_fenceable(vma)); ret = i915_vma_unbind(vma); if (ret) return ERR_PTR(ret); } ret = i915_vma_pin(vma, size, alignment, flags | PIN_GLOBAL); if (ret) return ERR_PTR(ret); return vma; } static __always_inline unsigned int __busy_read_flag(unsigned int id) { /* Note that we could alias engines in the execbuf API, but * that would be very unwise as it prevents userspace from * fine control over engine selection. Ahem. * * This should be something like EXEC_MAX_ENGINE instead of * I915_NUM_ENGINES. */ BUILD_BUG_ON(I915_NUM_ENGINES > 16); return 0x10000 << id; } static __always_inline unsigned int __busy_write_id(unsigned int id) { /* The uABI guarantees an active writer is also amongst the read * engines. This would be true if we accessed the activity tracking * under the lock, but as we perform the lookup of the object and * its activity locklessly we can not guarantee that the last_write * being active implies that we have set the same engine flag from * last_read - hence we always set both read and write busy for * last_write. */ return id | __busy_read_flag(id); } static __always_inline unsigned int __busy_set_if_active(const struct dma_fence *fence, unsigned int (*flag)(unsigned int id)) { struct drm_i915_gem_request *rq; /* We have to check the current hw status of the fence as the uABI * guarantees forward progress. We could rely on the idle worker * to eventually flush us, but to minimise latency just ask the * hardware. * * Note we only report on the status of native fences. */ if (!dma_fence_is_i915(fence)) return 0; /* opencode to_request() in order to avoid const warnings */ rq = container_of(fence, struct drm_i915_gem_request, fence); if (i915_gem_request_completed(rq)) return 0; return flag(rq->engine->uabi_id); } static __always_inline unsigned int busy_check_reader(const struct dma_fence *fence) { return __busy_set_if_active(fence, __busy_read_flag); } static __always_inline unsigned int busy_check_writer(const struct dma_fence *fence) { if (!fence) return 0; return __busy_set_if_active(fence, __busy_write_id); } int i915_gem_busy_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_busy *args = data; struct drm_i915_gem_object *obj; struct reservation_object_list *list; unsigned int seq; int err; err = -ENOENT; rcu_read_lock(); obj = i915_gem_object_lookup_rcu(file, args->handle); if (!obj) goto out; /* A discrepancy here is that we do not report the status of * non-i915 fences, i.e. even though we may report the object as idle, * a call to set-domain may still stall waiting for foreign rendering. * This also means that wait-ioctl may report an object as busy, * where busy-ioctl considers it idle. * * We trade the ability to warn of foreign fences to report on which * i915 engines are active for the object. * * Alternatively, we can trade that extra information on read/write * activity with * args->busy = * !reservation_object_test_signaled_rcu(obj->resv, true); * to report the overall busyness. This is what the wait-ioctl does. * */ retry: seq = raw_read_seqcount(&obj->resv->seq); /* Translate the exclusive fence to the READ *and* WRITE engine */ args->busy = busy_check_writer(rcu_dereference(obj->resv->fence_excl)); /* Translate shared fences to READ set of engines */ list = rcu_dereference(obj->resv->fence); if (list) { unsigned int shared_count = list->shared_count, i; for (i = 0; i < shared_count; ++i) { struct dma_fence *fence = rcu_dereference(list->shared[i]); args->busy |= busy_check_reader(fence); } } if (args->busy && read_seqcount_retry(&obj->resv->seq, seq)) goto retry; err = 0; out: rcu_read_unlock(); return err; } int i915_gem_throttle_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { return i915_gem_ring_throttle(dev, file_priv); } int i915_gem_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { struct drm_i915_private *dev_priv = to_i915(dev); struct drm_i915_gem_madvise *args = data; struct drm_i915_gem_object *obj; int err; switch (args->madv) { case I915_MADV_DONTNEED: case I915_MADV_WILLNEED: break; default: return -EINVAL; } obj = i915_gem_object_lookup(file_priv, args->handle); if (!obj) return -ENOENT; err = mutex_lock_interruptible(&obj->mm.lock); if (err) goto out; if (obj->mm.pages && i915_gem_object_is_tiled(obj) && dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES) { if (obj->mm.madv == I915_MADV_WILLNEED) { GEM_BUG_ON(!obj->mm.quirked); __i915_gem_object_unpin_pages(obj); obj->mm.quirked = false; } if (args->madv == I915_MADV_WILLNEED) { GEM_BUG_ON(obj->mm.quirked); __i915_gem_object_pin_pages(obj); obj->mm.quirked = true; } } if (obj->mm.madv != __I915_MADV_PURGED) obj->mm.madv = args->madv; /* if the object is no longer attached, discard its backing storage */ if (obj->mm.madv == I915_MADV_DONTNEED && !obj->mm.pages) i915_gem_object_truncate(obj); args->retained = obj->mm.madv != __I915_MADV_PURGED; mutex_unlock(&obj->mm.lock); out: i915_gem_object_put(obj); return err; } static void frontbuffer_retire(struct i915_gem_active *active, struct drm_i915_gem_request *request) { struct drm_i915_gem_object *obj = container_of(active, typeof(*obj), frontbuffer_write); intel_fb_obj_flush(obj, ORIGIN_CS); } void i915_gem_object_init(struct drm_i915_gem_object *obj, const struct drm_i915_gem_object_ops *ops) { mutex_init(&obj->mm.lock); INIT_LIST_HEAD(&obj->global_link); INIT_LIST_HEAD(&obj->vma_list); INIT_LIST_HEAD(&obj->lut_list); INIT_LIST_HEAD(&obj->batch_pool_link); obj->ops = ops; reservation_object_init(&obj->__builtin_resv); obj->resv = &obj->__builtin_resv; obj->frontbuffer_ggtt_origin = ORIGIN_GTT; init_request_active(&obj->frontbuffer_write, frontbuffer_retire); 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); i915_gem_info_add_obj(to_i915(obj->base.dev), obj->base.size); } static const struct drm_i915_gem_object_ops i915_gem_object_ops = { .flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE | I915_GEM_OBJECT_IS_SHRINKABLE, .get_pages = i915_gem_object_get_pages_gtt, .put_pages = i915_gem_object_put_pages_gtt, .pwrite = i915_gem_object_pwrite_gtt, }; static int i915_gem_object_create_shmem(struct drm_device *dev, struct drm_gem_object *obj, size_t size) { struct drm_i915_private *i915 = to_i915(dev); unsigned long flags = VM_NORESERVE; struct file *filp; drm_gem_private_object_init(dev, obj, size); if (i915->mm.gemfs) filp = shmem_file_setup_with_mnt(i915->mm.gemfs, "i915", size, flags); else filp = shmem_file_setup("i915", size, flags); if (IS_ERR(filp)) return PTR_ERR(filp); obj->filp = filp; return 0; } struct drm_i915_gem_object * i915_gem_object_create(struct drm_i915_private *dev_priv, u64 size) { struct drm_i915_gem_object *obj; struct address_space *mapping; unsigned int cache_level; gfp_t mask; int ret; /* There is a prevalence of the assumption that we fit the object's * page count inside a 32bit _signed_ variable. Let's document this and * catch if we ever need to fix it. In the meantime, if you do spot * such a local variable, please consider fixing! */ if (size >> PAGE_SHIFT > INT_MAX) return ERR_PTR(-E2BIG); if (overflows_type(size, obj->base.size)) return ERR_PTR(-E2BIG); obj = i915_gem_object_alloc(dev_priv); if (obj == NULL) return ERR_PTR(-ENOMEM); ret = i915_gem_object_create_shmem(&dev_priv->drm, &obj->base, size); if (ret) goto fail; mask = GFP_HIGHUSER | __GFP_RECLAIMABLE; if (IS_I965GM(dev_priv) || IS_I965G(dev_priv)) { /* 965gm cannot relocate objects above 4GiB. */ mask &= ~__GFP_HIGHMEM; mask |= __GFP_DMA32; } mapping = obj->base.filp->f_mapping; mapping_set_gfp_mask(mapping, mask); GEM_BUG_ON(!(mapping_gfp_mask(mapping) & __GFP_RECLAIM)); i915_gem_object_init(obj, &i915_gem_object_ops); obj->base.write_domain = I915_GEM_DOMAIN_CPU; obj->base.read_domains = I915_GEM_DOMAIN_CPU; if (HAS_LLC(dev_priv)) /* On some devices, we can have the GPU use the LLC (the CPU * cache) for about a 10% performance improvement * compared to uncached. Graphics requests other than * display scanout are coherent with the CPU in * accessing this cache. This means in this mode we * don't need to clflush on the CPU side, and on the * GPU side we only need to flush internal caches to * get data visible to the CPU. * * However, we maintain the display planes as UC, and so * need to rebind when first used as such. */ cache_level = I915_CACHE_LLC; else cache_level = I915_CACHE_NONE; i915_gem_object_set_cache_coherency(obj, cache_level); trace_i915_gem_object_create(obj); return obj; fail: i915_gem_object_free(obj); return ERR_PTR(ret); } static bool discard_backing_storage(struct drm_i915_gem_object *obj) { /* If we are the last user of the backing storage (be it shmemfs * pages or stolen etc), we know that the pages are going to be * immediately released. In this case, we can then skip copying * back the contents from the GPU. */ if (obj->mm.madv != I915_MADV_WILLNEED) return false; if (obj->base.filp == NULL) return true; /* At first glance, this looks racy, but then again so would be * userspace racing mmap against close. However, the first external * reference to the filp can only be obtained through the * i915_gem_mmap_ioctl() which safeguards us against the user * acquiring such a reference whilst we are in the middle of * freeing the object. */ return atomic_long_read(&obj->base.filp->f_count) == 1; } static void __i915_gem_free_objects(struct drm_i915_private *i915, struct llist_node *freed) { struct drm_i915_gem_object *obj, *on; mutex_lock(&i915->drm.struct_mutex); intel_runtime_pm_get(i915); llist_for_each_entry(obj, freed, freed) { struct i915_vma *vma, *vn; trace_i915_gem_object_destroy(obj); GEM_BUG_ON(i915_gem_object_is_active(obj)); list_for_each_entry_safe(vma, vn, &obj->vma_list, obj_link) { GEM_BUG_ON(i915_vma_is_active(vma)); vma->flags &= ~I915_VMA_PIN_MASK; i915_vma_close(vma); } GEM_BUG_ON(!list_empty(&obj->vma_list)); GEM_BUG_ON(!RB_EMPTY_ROOT(&obj->vma_tree)); list_del(&obj->global_link); } intel_runtime_pm_put(i915); mutex_unlock(&i915->drm.struct_mutex); cond_resched(); llist_for_each_entry_safe(obj, on, freed, freed) { GEM_BUG_ON(obj->bind_count); GEM_BUG_ON(obj->userfault_count); GEM_BUG_ON(atomic_read(&obj->frontbuffer_bits)); GEM_BUG_ON(!list_empty(&obj->lut_list)); if (obj->ops->release) obj->ops->release(obj); if (WARN_ON(i915_gem_object_has_pinned_pages(obj))) atomic_set(&obj->mm.pages_pin_count, 0); __i915_gem_object_put_pages(obj, I915_MM_NORMAL); GEM_BUG_ON(obj->mm.pages); if (obj->base.import_attach) drm_prime_gem_destroy(&obj->base, NULL); reservation_object_fini(&obj->__builtin_resv); drm_gem_object_release(&obj->base); i915_gem_info_remove_obj(i915, obj->base.size); kfree(obj->bit_17); i915_gem_object_free(obj); } } static void i915_gem_flush_free_objects(struct drm_i915_private *i915) { struct llist_node *freed; 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); struct llist_node *freed; /* All file-owned VMA should have been released by this point through * i915_gem_close_object(), or earlier by i915_gem_context_close(). * However, the object may also be bound into the global GTT (e.g. * older GPUs without per-process support, or for direct access through * the GTT either for the user or for scanout). Those VMA still need to * unbound now. */ while ((freed = llist_del_all(&i915->mm.free_list))) { __i915_gem_free_objects(i915, freed); if (need_resched()) break; } } static 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); /* We can't simply use call_rcu() from i915_gem_free_object() * as we need to block whilst unbinding, and the call_rcu * task may be called from softirq context. So we take a * detour through a worker. */ if (llist_add(&obj->freed, &i915->mm.free_list)) schedule_work(&i915->mm.free_work); } void i915_gem_free_object(struct drm_gem_object *gem_obj) { struct drm_i915_gem_object *obj = to_intel_bo(gem_obj); if (obj->mm.quirked) __i915_gem_object_unpin_pages(obj); if (discard_backing_storage(obj)) obj->mm.madv = I915_MADV_DONTNEED; /* 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(). */ call_rcu(&obj->rcu, __i915_gem_free_object_rcu); } void __i915_gem_object_release_unless_active(struct drm_i915_gem_object *obj) { lockdep_assert_held(&obj->base.dev->struct_mutex); if (!i915_gem_object_has_active_reference(obj) && i915_gem_object_is_active(obj)) i915_gem_object_set_active_reference(obj); else i915_gem_object_put(obj); } static void assert_kernel_context_is_current(struct drm_i915_private *dev_priv) { struct intel_engine_cs *engine; enum intel_engine_id id; for_each_engine(engine, dev_priv, id) GEM_BUG_ON(engine->last_retired_context && !i915_gem_context_is_kernel(engine->last_retired_context)); } void i915_gem_sanitize(struct drm_i915_private *i915) { if (i915_terminally_wedged(&i915->gpu_error)) { mutex_lock(&i915->drm.struct_mutex); i915_gem_unset_wedged(i915); mutex_unlock(&i915->drm.struct_mutex); } /* * If we inherit context state from the BIOS or earlier occupants * of the GPU, the GPU may be in an inconsistent state when we * try to take over. The only way to remove the earlier state * is by resetting. However, resetting on earlier gen is tricky as * it may impact the display and we are uncertain about the stability * of the reset, so this could be applied to even earlier gen. */ if (INTEL_GEN(i915) >= 5) { int reset = intel_gpu_reset(i915, ALL_ENGINES); WARN_ON(reset && reset != -ENODEV); } } int i915_gem_suspend(struct drm_i915_private *dev_priv) { struct drm_device *dev = &dev_priv->drm; int ret; intel_runtime_pm_get(dev_priv); intel_suspend_gt_powersave(dev_priv); mutex_lock(&dev->struct_mutex); /* We have to flush all the executing contexts to main memory so * that they can saved in the hibernation image. To ensure the last * context image is coherent, we have to switch away from it. That * leaves the dev_priv->kernel_context still active when * we actually suspend, and its image in memory may not match the GPU * state. Fortunately, the kernel_context is disposable and we do * not rely on its state. */ ret = i915_gem_switch_to_kernel_context(dev_priv); if (ret) goto err_unlock; ret = i915_gem_wait_for_idle(dev_priv, I915_WAIT_INTERRUPTIBLE | I915_WAIT_LOCKED); if (ret && ret != -EIO) goto err_unlock; assert_kernel_context_is_current(dev_priv); i915_gem_contexts_lost(dev_priv); mutex_unlock(&dev->struct_mutex); intel_guc_suspend(dev_priv); cancel_delayed_work_sync(&dev_priv->gpu_error.hangcheck_work); cancel_delayed_work_sync(&dev_priv->gt.retire_work); /* As the idle_work is rearming if it detects a race, play safe and * repeat the flush until it is definitely idle. */ drain_delayed_work(&dev_priv->gt.idle_work); /* Assert that we sucessfully flushed all the work and * reset the GPU back to its idle, low power state. */ WARN_ON(dev_priv->gt.awake); if (WARN_ON(!intel_engines_are_idle(dev_priv))) i915_gem_set_wedged(dev_priv); /* no hope, discard everything */ /* * Neither the BIOS, ourselves or any other kernel * expects the system to be in execlists mode on startup, * so we need to reset the GPU back to legacy mode. And the only * known way to disable logical contexts is through a GPU reset. * * So in order to leave the system in a known default configuration, * always reset the GPU upon unload and suspend. Afterwards we then * clean up the GEM state tracking, flushing off the requests and * leaving the system in a known idle state. * * Note that is of the upmost importance that the GPU is idle and * all stray writes are flushed *before* we dismantle the backing * storage for the pinned objects. * * However, since we are uncertain that resetting the GPU on older * machines is a good idea, we don't - just in case it leaves the * machine in an unusable condition. */ i915_gem_sanitize(dev_priv); intel_runtime_pm_put(dev_priv); return 0; err_unlock: mutex_unlock(&dev->struct_mutex); intel_runtime_pm_put(dev_priv); return ret; } void i915_gem_resume(struct drm_i915_private *dev_priv) { struct drm_device *dev = &dev_priv->drm; WARN_ON(dev_priv->gt.awake); mutex_lock(&dev->struct_mutex); i915_gem_restore_gtt_mappings(dev_priv); i915_gem_restore_fences(dev_priv); /* As we didn't flush the kernel context before suspend, we cannot * guarantee that the context image is complete. So let's just reset * it and start again. */ dev_priv->gt.resume(dev_priv); mutex_unlock(&dev->struct_mutex); } void i915_gem_init_swizzling(struct drm_i915_private *dev_priv) { if (INTEL_GEN(dev_priv) < 5 || dev_priv->mm.bit_6_swizzle_x == I915_BIT_6_SWIZZLE_NONE) return; I915_WRITE(DISP_ARB_CTL, I915_READ(DISP_ARB_CTL) | DISP_TILE_SURFACE_SWIZZLING); if (IS_GEN5(dev_priv)) return; I915_WRITE(TILECTL, I915_READ(TILECTL) | TILECTL_SWZCTL); if (IS_GEN6(dev_priv)) I915_WRITE(ARB_MODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_SNB)); else if (IS_GEN7(dev_priv)) I915_WRITE(ARB_MODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_IVB)); else if (IS_GEN8(dev_priv)) I915_WRITE(GAMTARBMODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_BDW)); else BUG(); } static void init_unused_ring(struct drm_i915_private *dev_priv, u32 base) { I915_WRITE(RING_CTL(base), 0); I915_WRITE(RING_HEAD(base), 0); I915_WRITE(RING_TAIL(base), 0); I915_WRITE(RING_START(base), 0); } static void init_unused_rings(struct drm_i915_private *dev_priv) { if (IS_I830(dev_priv)) { init_unused_ring(dev_priv, PRB1_BASE); init_unused_ring(dev_priv, SRB0_BASE); init_unused_ring(dev_priv, SRB1_BASE); init_unused_ring(dev_priv, SRB2_BASE); init_unused_ring(dev_priv, SRB3_BASE); } else if (IS_GEN2(dev_priv)) { init_unused_ring(dev_priv, SRB0_BASE); init_unused_ring(dev_priv, SRB1_BASE); } else if (IS_GEN3(dev_priv)) { init_unused_ring(dev_priv, PRB1_BASE); init_unused_ring(dev_priv, PRB2_BASE); } } static int __i915_gem_restart_engines(void *data) { struct drm_i915_private *i915 = data; struct intel_engine_cs *engine; enum intel_engine_id id; int err; for_each_engine(engine, i915, id) { err = engine->init_hw(engine); if (err) return err; } return 0; } int i915_gem_init_hw(struct drm_i915_private *dev_priv) { int ret; dev_priv->gt.last_init_time = ktime_get(); /* Double layer security blanket, see i915_gem_init() */ intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL); if (HAS_EDRAM(dev_priv) && INTEL_GEN(dev_priv) < 9) I915_WRITE(HSW_IDICR, I915_READ(HSW_IDICR) | IDIHASHMSK(0xf)); if (IS_HASWELL(dev_priv)) I915_WRITE(MI_PREDICATE_RESULT_2, IS_HSW_GT3(dev_priv) ? LOWER_SLICE_ENABLED : LOWER_SLICE_DISABLED); if (HAS_PCH_NOP(dev_priv)) { if (IS_IVYBRIDGE(dev_priv)) { u32 temp = I915_READ(GEN7_MSG_CTL); temp &= ~(WAIT_FOR_PCH_FLR_ACK | WAIT_FOR_PCH_RESET_ACK); I915_WRITE(GEN7_MSG_CTL, temp); } else if (INTEL_GEN(dev_priv) >= 7) { u32 temp = I915_READ(HSW_NDE_RSTWRN_OPT); temp &= ~RESET_PCH_HANDSHAKE_ENABLE; I915_WRITE(HSW_NDE_RSTWRN_OPT, temp); } } i915_gem_init_swizzling(dev_priv); /* * At least 830 can leave some of the unused rings * "active" (ie. head != tail) after resume which * will prevent c3 entry. Makes sure all unused rings * are totally idle. */ init_unused_rings(dev_priv); BUG_ON(!dev_priv->kernel_context); ret = i915_ppgtt_init_hw(dev_priv); if (ret) { DRM_ERROR("PPGTT enable HW failed %d\n", ret); goto out; } /* Need to do basic initialisation of all rings first: */ ret = __i915_gem_restart_engines(dev_priv); if (ret) goto out; intel_mocs_init_l3cc_table(dev_priv); /* We can't enable contexts until all firmware is loaded */ ret = intel_uc_init_hw(dev_priv); if (ret) goto out; out: intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL); return ret; } bool intel_sanitize_semaphores(struct drm_i915_private *dev_priv, int value) { if (INTEL_INFO(dev_priv)->gen < 6) return false; /* TODO: make semaphores and Execlists play nicely together */ if (i915_modparams.enable_execlists) return false; if (value >= 0) return value; /* Enable semaphores on SNB when IO remapping is off */ if (IS_GEN6(dev_priv) && intel_vtd_active()) return false; return true; } int i915_gem_init(struct drm_i915_private *dev_priv) { int ret; mutex_lock(&dev_priv->drm.struct_mutex); /* * We need to fallback to 4K pages since gvt gtt handling doesn't * support huge page entries - we will need to check either hypervisor * mm can support huge guest page or just do emulation in gvt. */ if (intel_vgpu_active(dev_priv)) mkwrite_device_info(dev_priv)->page_sizes = I915_GTT_PAGE_SIZE_4K; dev_priv->mm.unordered_timeline = dma_fence_context_alloc(1); if (!i915_modparams.enable_execlists) { dev_priv->gt.resume = intel_legacy_submission_resume; dev_priv->gt.cleanup_engine = intel_engine_cleanup; } else { dev_priv->gt.resume = intel_lr_context_resume; dev_priv->gt.cleanup_engine = intel_logical_ring_cleanup; } /* This is just a security blanket to placate dragons. * On some systems, we very sporadically observe that the first TLBs * used by the CS may be stale, despite us poking the TLB reset. If * we hold the forcewake during initialisation these problems * just magically go away. */ intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL); ret = i915_gem_init_userptr(dev_priv); if (ret) goto out_unlock; ret = i915_gem_init_ggtt(dev_priv); if (ret) goto out_unlock; ret = i915_gem_contexts_init(dev_priv); if (ret) goto out_unlock; ret = intel_engines_init(dev_priv); if (ret) goto out_unlock; ret = i915_gem_init_hw(dev_priv); if (ret == -EIO) { /* Allow engine initialisation to fail by marking the GPU as * wedged. But we only want to do this where the GPU is angry, * for all other failure, such as an allocation failure, bail. */ DRM_ERROR("Failed to initialize GPU, declaring it wedged\n"); i915_gem_set_wedged(dev_priv); ret = 0; } out_unlock: intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL); mutex_unlock(&dev_priv->drm.struct_mutex); return ret; } void i915_gem_init_mmio(struct drm_i915_private *i915) { i915_gem_sanitize(i915); } void i915_gem_cleanup_engines(struct drm_i915_private *dev_priv) { struct intel_engine_cs *engine; enum intel_engine_id id; for_each_engine(engine, dev_priv, id) dev_priv->gt.cleanup_engine(engine); } void i915_gem_load_init_fences(struct drm_i915_private *dev_priv) { int i; if (INTEL_INFO(dev_priv)->gen >= 7 && !IS_VALLEYVIEW(dev_priv) && !IS_CHERRYVIEW(dev_priv)) dev_priv->num_fence_regs = 32; else if (INTEL_INFO(dev_priv)->gen >= 4 || IS_I945G(dev_priv) || IS_I945GM(dev_priv) || IS_G33(dev_priv) || IS_PINEVIEW(dev_priv)) dev_priv->num_fence_regs = 16; else dev_priv->num_fence_regs = 8; if (intel_vgpu_active(dev_priv)) dev_priv->num_fence_regs = I915_READ(vgtif_reg(avail_rs.fence_num)); /* Initialize fence registers to zero */ for (i = 0; i < dev_priv->num_fence_regs; i++) { struct drm_i915_fence_reg *fence = &dev_priv->fence_regs[i]; fence->i915 = dev_priv; fence->id = i; list_add_tail(&fence->link, &dev_priv->mm.fence_list); } i915_gem_restore_fences(dev_priv); i915_gem_detect_bit_6_swizzle(dev_priv); } int i915_gem_load_init(struct drm_i915_private *dev_priv) { int err = -ENOMEM; dev_priv->objects = KMEM_CACHE(drm_i915_gem_object, SLAB_HWCACHE_ALIGN); if (!dev_priv->objects) goto err_out; dev_priv->vmas = KMEM_CACHE(i915_vma, SLAB_HWCACHE_ALIGN); if (!dev_priv->vmas) goto err_objects; dev_priv->luts = KMEM_CACHE(i915_lut_handle, 0); if (!dev_priv->luts) goto err_vmas; dev_priv->requests = KMEM_CACHE(drm_i915_gem_request, SLAB_HWCACHE_ALIGN | SLAB_RECLAIM_ACCOUNT | SLAB_TYPESAFE_BY_RCU); if (!dev_priv->requests) goto err_luts; dev_priv->dependencies = KMEM_CACHE(i915_dependency, SLAB_HWCACHE_ALIGN | SLAB_RECLAIM_ACCOUNT); if (!dev_priv->dependencies) goto err_requests; dev_priv->priorities = KMEM_CACHE(i915_priolist, SLAB_HWCACHE_ALIGN); if (!dev_priv->priorities) goto err_dependencies; mutex_lock(&dev_priv->drm.struct_mutex); INIT_LIST_HEAD(&dev_priv->gt.timelines); err = i915_gem_timeline_init__global(dev_priv); mutex_unlock(&dev_priv->drm.struct_mutex); if (err) goto err_priorities; INIT_WORK(&dev_priv->mm.free_work, __i915_gem_free_work); init_llist_head(&dev_priv->mm.free_list); INIT_LIST_HEAD(&dev_priv->mm.unbound_list); INIT_LIST_HEAD(&dev_priv->mm.bound_list); INIT_LIST_HEAD(&dev_priv->mm.fence_list); INIT_LIST_HEAD(&dev_priv->mm.userfault_list); INIT_DELAYED_WORK(&dev_priv->gt.retire_work, i915_gem_retire_work_handler); INIT_DELAYED_WORK(&dev_priv->gt.idle_work, i915_gem_idle_work_handler); init_waitqueue_head(&dev_priv->gpu_error.wait_queue); init_waitqueue_head(&dev_priv->gpu_error.reset_queue); atomic_set(&dev_priv->mm.bsd_engine_dispatch_index, 0); spin_lock_init(&dev_priv->fb_tracking.lock); err = i915_gemfs_init(dev_priv); if (err) DRM_NOTE("Unable to create a private tmpfs mount, hugepage support will be disabled(%d).\n", err); return 0; err_priorities: kmem_cache_destroy(dev_priv->priorities); err_dependencies: kmem_cache_destroy(dev_priv->dependencies); err_requests: kmem_cache_destroy(dev_priv->requests); err_luts: kmem_cache_destroy(dev_priv->luts); err_vmas: kmem_cache_destroy(dev_priv->vmas); err_objects: kmem_cache_destroy(dev_priv->objects); err_out: return err; } void i915_gem_load_cleanup(struct drm_i915_private *dev_priv) { i915_gem_drain_freed_objects(dev_priv); WARN_ON(!llist_empty(&dev_priv->mm.free_list)); WARN_ON(dev_priv->mm.object_count); mutex_lock(&dev_priv->drm.struct_mutex); i915_gem_timeline_fini(&dev_priv->gt.global_timeline); WARN_ON(!list_empty(&dev_priv->gt.timelines)); mutex_unlock(&dev_priv->drm.struct_mutex); kmem_cache_destroy(dev_priv->priorities); kmem_cache_destroy(dev_priv->dependencies); kmem_cache_destroy(dev_priv->requests); kmem_cache_destroy(dev_priv->luts); kmem_cache_destroy(dev_priv->vmas); kmem_cache_destroy(dev_priv->objects); /* And ensure that our DESTROY_BY_RCU slabs are truly destroyed */ rcu_barrier(); i915_gemfs_fini(dev_priv); } int i915_gem_freeze(struct drm_i915_private *dev_priv) { /* Discard all purgeable objects, let userspace recover those as * required after resuming. */ i915_gem_shrink_all(dev_priv); return 0; } int i915_gem_freeze_late(struct drm_i915_private *dev_priv) { struct drm_i915_gem_object *obj; struct list_head *phases[] = { &dev_priv->mm.unbound_list, &dev_priv->mm.bound_list, NULL }, **p; /* Called just before we write the hibernation image. * * We need to update the domain tracking to reflect that the CPU * will be accessing all the pages to create and restore from the * hibernation, and so upon restoration those pages will be in the * CPU domain. * * To make sure the hibernation image contains the latest state, * we update that state just before writing out the image. * * To try and reduce the hibernation image, we manually shrink * the objects as well, see i915_gem_freeze() */ i915_gem_shrink(dev_priv, -1UL, NULL, I915_SHRINK_UNBOUND); i915_gem_drain_freed_objects(dev_priv); mutex_lock(&dev_priv->drm.struct_mutex); for (p = phases; *p; p++) { list_for_each_entry(obj, *p, global_link) __start_cpu_write(obj); } mutex_unlock(&dev_priv->drm.struct_mutex); return 0; } void i915_gem_release(struct drm_device *dev, struct drm_file *file) { struct drm_i915_file_private *file_priv = file->driver_priv; struct drm_i915_gem_request *request; /* Clean up our request list when the client is going away, so that * later retire_requests won't dereference our soon-to-be-gone * file_priv. */ spin_lock(&file_priv->mm.lock); list_for_each_entry(request, &file_priv->mm.request_list, client_link) request->file_priv = NULL; spin_unlock(&file_priv->mm.lock); } int i915_gem_open(struct drm_i915_private *i915, struct drm_file *file) { struct drm_i915_file_private *file_priv; int ret; DRM_DEBUG("\n"); file_priv = kzalloc(sizeof(*file_priv), GFP_KERNEL); if (!file_priv) return -ENOMEM; file->driver_priv = file_priv; file_priv->dev_priv = i915; file_priv->file = file; spin_lock_init(&file_priv->mm.lock); INIT_LIST_HEAD(&file_priv->mm.request_list); file_priv->bsd_engine = -1; ret = i915_gem_context_open(i915, file); if (ret) kfree(file_priv); return ret; } /** * i915_gem_track_fb - update frontbuffer tracking * @old: current GEM buffer for the frontbuffer slots * @new: new GEM buffer for the frontbuffer slots * @frontbuffer_bits: bitmask of frontbuffer slots * * This updates the frontbuffer tracking bits @frontbuffer_bits by clearing them * from @old and setting them in @new. Both @old and @new can be NULL. */ void i915_gem_track_fb(struct drm_i915_gem_object *old, struct drm_i915_gem_object *new, unsigned frontbuffer_bits) { /* Control of individual bits within the mask are guarded by * the owning plane->mutex, i.e. we can never see concurrent * manipulation of individual bits. But since the bitfield as a whole * is updated using RMW, we need to use atomics in order to update * the bits. */ BUILD_BUG_ON(INTEL_FRONTBUFFER_BITS_PER_PIPE * I915_MAX_PIPES > sizeof(atomic_t) * BITS_PER_BYTE); if (old) { WARN_ON(!(atomic_read(&old->frontbuffer_bits) & frontbuffer_bits)); atomic_andnot(frontbuffer_bits, &old->frontbuffer_bits); } if (new) { WARN_ON(atomic_read(&new->frontbuffer_bits) & frontbuffer_bits); atomic_or(frontbuffer_bits, &new->frontbuffer_bits); } } /* Allocate a new GEM object and fill it with the supplied data */ struct drm_i915_gem_object * i915_gem_object_create_from_data(struct drm_i915_private *dev_priv, const void *data, size_t size) { struct drm_i915_gem_object *obj; struct file *file; size_t offset; int err; obj = i915_gem_object_create(dev_priv, round_up(size, PAGE_SIZE)); if (IS_ERR(obj)) return obj; GEM_BUG_ON(obj->base.write_domain != I915_GEM_DOMAIN_CPU); file = obj->base.filp; offset = 0; do { unsigned int len = min_t(typeof(size), size, PAGE_SIZE); struct page *page; void *pgdata, *vaddr; err = pagecache_write_begin(file, file->f_mapping, offset, len, 0, &page, &pgdata); if (err < 0) goto fail; vaddr = kmap(page); memcpy(vaddr, data, len); kunmap(page); err = pagecache_write_end(file, file->f_mapping, offset, len, len, page, pgdata); if (err < 0) goto fail; size -= len; data += len; offset += len; } while (size); return obj; fail: i915_gem_object_put(obj); return ERR_PTR(err); } struct scatterlist * i915_gem_object_get_sg(struct drm_i915_gem_object *obj, unsigned int n, unsigned int *offset) { struct i915_gem_object_page_iter *iter = &obj->mm.get_page; struct scatterlist *sg; unsigned int idx, count; might_sleep(); GEM_BUG_ON(n >= obj->base.size >> PAGE_SHIFT); GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj)); /* As we iterate forward through the sg, we record each entry in a * radixtree for quick repeated (backwards) lookups. If we have seen * this index previously, we will have an entry for it. * * Initial lookup is O(N), but this is amortized to O(1) for * sequential page access (where each new request is consecutive * to the previous one). Repeated lookups are O(lg(obj->base.size)), * i.e. O(1) with a large constant! */ if (n < READ_ONCE(iter->sg_idx)) goto lookup; mutex_lock(&iter->lock); /* We prefer to reuse the last sg so that repeated lookup of this * (or the subsequent) sg are fast - comparing against the last * sg is faster than going through the radixtree. */ sg = iter->sg_pos; idx = iter->sg_idx; count = __sg_page_count(sg); while (idx + count <= n) { unsigned long exception, i; int ret; /* If we cannot allocate and insert this entry, or the * individual pages from this range, cancel updating the * sg_idx so that on this lookup we are forced to linearly * scan onwards, but on future lookups we will try the * insertion again (in which case we need to be careful of * the error return reporting that we have already inserted * this index). */ ret = radix_tree_insert(&iter->radix, idx, sg); if (ret && ret != -EEXIST) goto scan; exception = RADIX_TREE_EXCEPTIONAL_ENTRY | idx << RADIX_TREE_EXCEPTIONAL_SHIFT; for (i = 1; i < count; i++) { ret = radix_tree_insert(&iter->radix, idx + i, (void *)exception); if (ret && ret != -EEXIST) goto scan; } idx += count; sg = ____sg_next(sg); count = __sg_page_count(sg); } scan: iter->sg_pos = sg; iter->sg_idx = idx; mutex_unlock(&iter->lock); if (unlikely(n < idx)) /* insertion completed by another thread */ goto lookup; /* In case we failed to insert the entry into the radixtree, we need * to look beyond the current sg. */ while (idx + count <= n) { idx += count; sg = ____sg_next(sg); count = __sg_page_count(sg); } *offset = n - idx; return sg; lookup: rcu_read_lock(); sg = radix_tree_lookup(&iter->radix, n); GEM_BUG_ON(!sg); /* If this index is in the middle of multi-page sg entry, * the radixtree will contain an exceptional entry that points * to the start of that range. We will return the pointer to * the base page and the offset of this page within the * sg entry's range. */ *offset = 0; if (unlikely(radix_tree_exception(sg))) { unsigned long base = (unsigned long)sg >> RADIX_TREE_EXCEPTIONAL_SHIFT; sg = radix_tree_lookup(&iter->radix, base); GEM_BUG_ON(!sg); *offset = n - base; } rcu_read_unlock(); return sg; } struct page * i915_gem_object_get_page(struct drm_i915_gem_object *obj, unsigned int n) { struct scatterlist *sg; unsigned int offset; GEM_BUG_ON(!i915_gem_object_has_struct_page(obj)); sg = i915_gem_object_get_sg(obj, n, &offset); return nth_page(sg_page(sg), offset); } /* Like i915_gem_object_get_page(), but mark the returned page dirty */ struct page * i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj, unsigned int n) { struct page *page; page = i915_gem_object_get_page(obj, n); if (!obj->mm.dirty) set_page_dirty(page); return page; } dma_addr_t i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj, unsigned long n) { struct scatterlist *sg; unsigned int offset; sg = i915_gem_object_get_sg(obj, n, &offset); return sg_dma_address(sg) + (offset << PAGE_SHIFT); } int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align) { struct sg_table *pages; int err; if (align > obj->base.size) return -EINVAL; if (obj->ops == &i915_gem_phys_ops) return 0; if (obj->ops != &i915_gem_object_ops) return -EINVAL; err = i915_gem_object_unbind(obj); if (err) return err; mutex_lock(&obj->mm.lock); if (obj->mm.madv != I915_MADV_WILLNEED) { err = -EFAULT; goto err_unlock; } if (obj->mm.quirked) { err = -EFAULT; goto err_unlock; } if (obj->mm.mapping) { err = -EBUSY; goto err_unlock; } pages = obj->mm.pages; obj->ops = &i915_gem_phys_ops; err = ____i915_gem_object_get_pages(obj); if (err) goto err_xfer; /* Perma-pin (until release) the physical set of pages */ __i915_gem_object_pin_pages(obj); if (!IS_ERR_OR_NULL(pages)) i915_gem_object_ops.put_pages(obj, pages); mutex_unlock(&obj->mm.lock); return 0; err_xfer: obj->ops = &i915_gem_object_ops; obj->mm.pages = pages; err_unlock: mutex_unlock(&obj->mm.lock); return err; } #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) #include "selftests/scatterlist.c" #include "selftests/mock_gem_device.c" #include "selftests/huge_gem_object.c" #include "selftests/huge_pages.c" #include "selftests/i915_gem_object.c" #include "selftests/i915_gem_coherency.c" #endif