/* * Copyright © 2008 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 "i915_drv.h" #include "i915_trace.h" #include "intel_drv.h" #include #include #include #include #include static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj); static void i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj); static __must_check int i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, unsigned alignment, bool map_and_fenceable, bool nonblocking); static int i915_gem_phys_pwrite(struct drm_device *dev, struct drm_i915_gem_object *obj, struct drm_i915_gem_pwrite *args, struct drm_file *file); static void i915_gem_write_fence(struct drm_device *dev, int reg, struct drm_i915_gem_object *obj); static void i915_gem_object_update_fence(struct drm_i915_gem_object *obj, struct drm_i915_fence_reg *fence, bool enable); static int i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc); static long i915_gem_purge(struct drm_i915_private *dev_priv, long target); static void i915_gem_shrink_all(struct drm_i915_private *dev_priv); static void i915_gem_object_truncate(struct drm_i915_gem_object *obj); static inline void i915_gem_object_fence_lost(struct drm_i915_gem_object *obj) { if (obj->tiling_mode) i915_gem_release_mmap(obj); /* As we do not have an associated fence register, we will force * a tiling change if we ever need to acquire one. */ obj->fence_dirty = false; obj->fence_reg = I915_FENCE_REG_NONE; } /* some bookkeeping */ static void i915_gem_info_add_obj(struct drm_i915_private *dev_priv, size_t size) { dev_priv->mm.object_count++; dev_priv->mm.object_memory += size; } static void i915_gem_info_remove_obj(struct drm_i915_private *dev_priv, size_t size) { dev_priv->mm.object_count--; dev_priv->mm.object_memory -= size; } static int i915_gem_wait_for_error(struct i915_gpu_error *error) { int ret; #define EXIT_COND (!i915_reset_in_progress(error) || \ i915_terminally_wedged(error)) if (EXIT_COND) return 0; /* * 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, EXIT_COND, 10*HZ); if (ret == 0) { DRM_ERROR("Timed out waiting for the gpu reset to complete\n"); return -EIO; } else if (ret < 0) { return ret; } #undef EXIT_COND return 0; } int i915_mutex_lock_interruptible(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; 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; WARN_ON(i915_verify_lists(dev)); return 0; } static inline bool i915_gem_object_is_inactive(struct drm_i915_gem_object *obj) { return obj->gtt_space && !obj->active; } int i915_gem_init_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_init *args = data; if (drm_core_check_feature(dev, DRIVER_MODESET)) return -ENODEV; if (args->gtt_start >= args->gtt_end || (args->gtt_end | args->gtt_start) & (PAGE_SIZE - 1)) return -EINVAL; /* GEM with user mode setting was never supported on ilk and later. */ if (INTEL_INFO(dev)->gen >= 5) return -ENODEV; mutex_lock(&dev->struct_mutex); i915_gem_setup_global_gtt(dev, args->gtt_start, args->gtt_end, args->gtt_end); dev_priv->gtt.mappable_end = args->gtt_end; mutex_unlock(&dev->struct_mutex); return 0; } int i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_get_aperture *args = data; struct drm_i915_gem_object *obj; size_t pinned; pinned = 0; mutex_lock(&dev->struct_mutex); list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) if (obj->pin_count) pinned += obj->gtt_space->size; mutex_unlock(&dev->struct_mutex); args->aper_size = dev_priv->gtt.total; args->aper_available_size = args->aper_size - pinned; return 0; } void *i915_gem_object_alloc(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; return kmem_cache_alloc(dev_priv->slab, GFP_KERNEL | __GFP_ZERO); } void i915_gem_object_free(struct drm_i915_gem_object *obj) { struct drm_i915_private *dev_priv = obj->base.dev->dev_private; kmem_cache_free(dev_priv->slab, obj); } static int i915_gem_create(struct drm_file *file, struct drm_device *dev, 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_alloc_object(dev, size); if (obj == NULL) return -ENOMEM; ret = drm_gem_handle_create(file, &obj->base, &handle); if (ret) { drm_gem_object_release(&obj->base); i915_gem_info_remove_obj(dev->dev_private, obj->base.size); i915_gem_object_free(obj); return ret; } /* drop reference from allocate - handle holds it now */ drm_gem_object_unreference(&obj->base); trace_i915_gem_object_create(obj); *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 * ((args->bpp + 7) / 8), 64); args->size = args->pitch * args->height; return i915_gem_create(file, dev, args->size, &args->handle); } int i915_gem_dumb_destroy(struct drm_file *file, struct drm_device *dev, uint32_t handle) { return drm_gem_handle_delete(file, handle); } /** * Creates a new mm object and returns a handle to it. */ int i915_gem_create_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_create *args = data; return i915_gem_create(file, dev, args->size, &args->handle); } 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; } /* Per-page copy function for the shmem pread fastpath. * Flushes invalid cachelines before reading the target if * needs_clflush is set. */ static int shmem_pread_fast(struct page *page, int shmem_page_offset, int page_length, char __user *user_data, bool page_do_bit17_swizzling, bool needs_clflush) { char *vaddr; int ret; if (unlikely(page_do_bit17_swizzling)) return -EINVAL; vaddr = kmap_atomic(page); if (needs_clflush) drm_clflush_virt_range(vaddr + shmem_page_offset, page_length); ret = __copy_to_user_inatomic(user_data, vaddr + shmem_page_offset, page_length); kunmap_atomic(vaddr); return ret ? -EFAULT : 0; } 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 shmem_page_offset, int page_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 + shmem_page_offset, page_length, page_do_bit17_swizzling); if (page_do_bit17_swizzling) ret = __copy_to_user_swizzled(user_data, vaddr, shmem_page_offset, page_length); else ret = __copy_to_user(user_data, vaddr + shmem_page_offset, page_length); kunmap(page); return ret ? - EFAULT : 0; } static int i915_gem_shmem_pread(struct drm_device *dev, struct drm_i915_gem_object *obj, struct drm_i915_gem_pread *args, struct drm_file *file) { char __user *user_data; ssize_t remain; loff_t offset; int shmem_page_offset, page_length, ret = 0; int obj_do_bit17_swizzling, page_do_bit17_swizzling; int prefaulted = 0; int needs_clflush = 0; struct sg_page_iter sg_iter; user_data = to_user_ptr(args->data_ptr); remain = args->size; obj_do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj); if (!(obj->base.read_domains & 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_level == I915_CACHE_NONE) needs_clflush = 1; if (obj->gtt_space) { ret = i915_gem_object_set_to_gtt_domain(obj, false); if (ret) return ret; } } ret = i915_gem_object_get_pages(obj); if (ret) return ret; i915_gem_object_pin_pages(obj); offset = args->offset; for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, offset >> PAGE_SHIFT) { struct page *page = sg_page_iter_page(&sg_iter); if (remain <= 0) break; /* Operation in this page * * shmem_page_offset = offset within page in shmem file * page_length = bytes to copy for this page */ shmem_page_offset = offset_in_page(offset); page_length = remain; if ((shmem_page_offset + page_length) > PAGE_SIZE) page_length = PAGE_SIZE - shmem_page_offset; page_do_bit17_swizzling = obj_do_bit17_swizzling && (page_to_phys(page) & (1 << 17)) != 0; ret = shmem_pread_fast(page, shmem_page_offset, page_length, user_data, page_do_bit17_swizzling, needs_clflush); if (ret == 0) goto next_page; mutex_unlock(&dev->struct_mutex); if (!prefaulted) { ret = fault_in_multipages_writeable(user_data, remain); /* Userspace is tricking us, but we've already clobbered * its pages with the prefault and promised to write the * data up to the first fault. Hence ignore any errors * and just continue. */ (void)ret; prefaulted = 1; } ret = shmem_pread_slow(page, shmem_page_offset, page_length, user_data, page_do_bit17_swizzling, needs_clflush); mutex_lock(&dev->struct_mutex); next_page: mark_page_accessed(page); if (ret) goto out; remain -= page_length; user_data += page_length; offset += page_length; } out: i915_gem_object_unpin_pages(obj); return ret; } /** * Reads data from the object referenced by handle. * * 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 = 0; if (args->size == 0) return 0; if (!access_ok(VERIFY_WRITE, to_user_ptr(args->data_ptr), args->size)) return -EFAULT; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } /* Bounds check source. */ if (args->offset > obj->base.size || args->size > obj->base.size - args->offset) { ret = -EINVAL; goto out; } /* prime objects have no backing filp to GEM pread/pwrite * pages from. */ if (!obj->base.filp) { ret = -EINVAL; goto out; } trace_i915_gem_object_pread(obj, args->offset, args->size); ret = i915_gem_shmem_pread(dev, obj, args, file); out: drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } /* This is the fast write path which cannot handle * page faults in the source data */ static inline int fast_user_write(struct io_mapping *mapping, loff_t page_base, int page_offset, char __user *user_data, int length) { void __iomem *vaddr_atomic; void *vaddr; unsigned long unwritten; vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base); /* We can use the cpu mem copy function because this is X86. */ vaddr = (void __force*)vaddr_atomic + page_offset; unwritten = __copy_from_user_inatomic_nocache(vaddr, user_data, length); io_mapping_unmap_atomic(vaddr_atomic); return unwritten; } /** * This is the fast pwrite path, where we copy the data directly from the * user into the GTT, uncached. */ static int i915_gem_gtt_pwrite_fast(struct drm_device *dev, struct drm_i915_gem_object *obj, struct drm_i915_gem_pwrite *args, struct drm_file *file) { drm_i915_private_t *dev_priv = dev->dev_private; ssize_t remain; loff_t offset, page_base; char __user *user_data; int page_offset, page_length, ret; ret = i915_gem_object_pin(obj, 0, true, true); if (ret) goto out; ret = i915_gem_object_set_to_gtt_domain(obj, true); if (ret) goto out_unpin; ret = i915_gem_object_put_fence(obj); if (ret) goto out_unpin; user_data = to_user_ptr(args->data_ptr); remain = args->size; offset = obj->gtt_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 */ page_base = offset & PAGE_MASK; page_offset = offset_in_page(offset); page_length = remain; if ((page_offset + remain) > PAGE_SIZE) page_length = PAGE_SIZE - page_offset; /* 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 (fast_user_write(dev_priv->gtt.mappable, page_base, page_offset, user_data, page_length)) { ret = -EFAULT; goto out_unpin; } remain -= page_length; user_data += page_length; offset += page_length; } out_unpin: i915_gem_object_unpin(obj); out: return ret; } /* 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_fast(struct page *page, int shmem_page_offset, int page_length, char __user *user_data, bool page_do_bit17_swizzling, bool needs_clflush_before, bool needs_clflush_after) { char *vaddr; int ret; if (unlikely(page_do_bit17_swizzling)) return -EINVAL; vaddr = kmap_atomic(page); if (needs_clflush_before) drm_clflush_virt_range(vaddr + shmem_page_offset, page_length); ret = __copy_from_user_inatomic_nocache(vaddr + shmem_page_offset, user_data, page_length); if (needs_clflush_after) drm_clflush_virt_range(vaddr + shmem_page_offset, page_length); kunmap_atomic(vaddr); return ret ? -EFAULT : 0; } /* Only difference to the fast-path function is that this can handle bit17 * and uses non-atomic copy and kmap functions. */ static int shmem_pwrite_slow(struct page *page, int shmem_page_offset, int page_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 + shmem_page_offset, page_length, page_do_bit17_swizzling); if (page_do_bit17_swizzling) ret = __copy_from_user_swizzled(vaddr, shmem_page_offset, user_data, page_length); else ret = __copy_from_user(vaddr + shmem_page_offset, user_data, page_length); if (needs_clflush_after) shmem_clflush_swizzled_range(vaddr + shmem_page_offset, page_length, page_do_bit17_swizzling); kunmap(page); return ret ? -EFAULT : 0; } static int i915_gem_shmem_pwrite(struct drm_device *dev, struct drm_i915_gem_object *obj, struct drm_i915_gem_pwrite *args, struct drm_file *file) { ssize_t remain; loff_t offset; char __user *user_data; int shmem_page_offset, page_length, ret = 0; int obj_do_bit17_swizzling, page_do_bit17_swizzling; int hit_slowpath = 0; int needs_clflush_after = 0; int needs_clflush_before = 0; struct sg_page_iter sg_iter; user_data = to_user_ptr(args->data_ptr); remain = args->size; obj_do_bit17_swizzling = i915_gem_object_needs_bit17_swizzle(obj); if (obj->base.write_domain != I915_GEM_DOMAIN_CPU) { /* If we're not in the cpu write domain, set ourself into the gtt * write domain and manually flush cachelines (if 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_level == I915_CACHE_NONE) needs_clflush_after = 1; if (obj->gtt_space) { ret = i915_gem_object_set_to_gtt_domain(obj, true); if (ret) return ret; } } /* Same trick applies for invalidate partially written cachelines before * writing. */ if (!(obj->base.read_domains & I915_GEM_DOMAIN_CPU) && obj->cache_level == I915_CACHE_NONE) needs_clflush_before = 1; ret = i915_gem_object_get_pages(obj); if (ret) return ret; i915_gem_object_pin_pages(obj); offset = args->offset; obj->dirty = 1; for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, offset >> PAGE_SHIFT) { struct page *page = sg_page_iter_page(&sg_iter); int partial_cacheline_write; if (remain <= 0) break; /* Operation in this page * * shmem_page_offset = offset within page in shmem file * page_length = bytes to copy for this page */ shmem_page_offset = offset_in_page(offset); page_length = remain; if ((shmem_page_offset + page_length) > PAGE_SIZE) page_length = PAGE_SIZE - shmem_page_offset; /* 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 = needs_clflush_before && ((shmem_page_offset | page_length) & (boot_cpu_data.x86_clflush_size - 1)); page_do_bit17_swizzling = obj_do_bit17_swizzling && (page_to_phys(page) & (1 << 17)) != 0; ret = shmem_pwrite_fast(page, shmem_page_offset, page_length, user_data, page_do_bit17_swizzling, partial_cacheline_write, needs_clflush_after); if (ret == 0) goto next_page; hit_slowpath = 1; mutex_unlock(&dev->struct_mutex); ret = shmem_pwrite_slow(page, shmem_page_offset, page_length, user_data, page_do_bit17_swizzling, partial_cacheline_write, needs_clflush_after); mutex_lock(&dev->struct_mutex); next_page: set_page_dirty(page); mark_page_accessed(page); if (ret) goto out; remain -= page_length; user_data += page_length; offset += page_length; } out: i915_gem_object_unpin_pages(obj); if (hit_slowpath) { /* * Fixup: Flush cpu caches in case we didn't flush the dirty * cachelines in-line while writing and the object moved * out of the cpu write domain while we've dropped the lock. */ if (!needs_clflush_after && obj->base.write_domain != I915_GEM_DOMAIN_CPU) { i915_gem_clflush_object(obj); i915_gem_chipset_flush(dev); } } if (needs_clflush_after) i915_gem_chipset_flush(dev); return ret; } /** * Writes data to the object referenced by handle. * * 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, to_user_ptr(args->data_ptr), args->size)) return -EFAULT; ret = fault_in_multipages_readable(to_user_ptr(args->data_ptr), args->size); if (ret) return -EFAULT; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } /* Bounds check destination. */ if (args->offset > obj->base.size || args->size > obj->base.size - args->offset) { ret = -EINVAL; goto out; } /* prime objects have no backing filp to GEM pread/pwrite * pages from. */ if (!obj->base.filp) { ret = -EINVAL; goto out; } trace_i915_gem_object_pwrite(obj, args->offset, args->size); 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 (obj->phys_obj) { ret = i915_gem_phys_pwrite(dev, obj, args, file); goto out; } if (obj->cache_level == I915_CACHE_NONE && obj->tiling_mode == I915_TILING_NONE && obj->base.write_domain != I915_GEM_DOMAIN_CPU) { ret = i915_gem_gtt_pwrite_fast(dev, obj, args, file); /* 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. */ } if (ret == -EFAULT || ret == -ENOSPC) ret = i915_gem_shmem_pwrite(dev, obj, args, file); out: drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } int i915_gem_check_wedge(struct i915_gpu_error *error, bool interruptible) { if (i915_reset_in_progress(error)) { /* Non-interruptible callers can't handle -EAGAIN, hence return * -EIO unconditionally for these. */ if (!interruptible) return -EIO; /* Recovery complete, but the reset failed ... */ if (i915_terminally_wedged(error)) return -EIO; return -EAGAIN; } return 0; } /* * Compare seqno against outstanding lazy request. Emit a request if they are * equal. */ static int i915_gem_check_olr(struct intel_ring_buffer *ring, u32 seqno) { int ret; BUG_ON(!mutex_is_locked(&ring->dev->struct_mutex)); ret = 0; if (seqno == ring->outstanding_lazy_request) ret = i915_add_request(ring, NULL); return ret; } /** * __wait_seqno - wait until execution of seqno has finished * @ring: the ring expected to report seqno * @seqno: duh! * @reset_counter: reset sequence associated with the given seqno * @interruptible: do an interruptible wait (normally yes) * @timeout: in - how long to wait (NULL forever); out - how much time remaining * * Note: It is of utmost importance that the passed in seqno and reset_counter * values have been read by the caller in an smp safe manner. Where read-side * locks are involved, it is sufficient to read the reset_counter before * unlocking the lock that protects the seqno. For lockless tricks, the * reset_counter _must_ be read before, and an appropriate smp_rmb must be * inserted. * * Returns 0 if the seqno was found within the alloted time. Else returns the * errno with remaining time filled in timeout argument. */ static int __wait_seqno(struct intel_ring_buffer *ring, u32 seqno, unsigned reset_counter, bool interruptible, struct timespec *timeout) { drm_i915_private_t *dev_priv = ring->dev->dev_private; struct timespec before, now, wait_time={1,0}; unsigned long timeout_jiffies; long end; bool wait_forever = true; int ret; if (i915_seqno_passed(ring->get_seqno(ring, true), seqno)) return 0; trace_i915_gem_request_wait_begin(ring, seqno); if (timeout != NULL) { wait_time = *timeout; wait_forever = false; } timeout_jiffies = timespec_to_jiffies_timeout(&wait_time); if (WARN_ON(!ring->irq_get(ring))) return -ENODEV; /* Record current time in case interrupted by signal, or wedged * */ getrawmonotonic(&before); #define EXIT_COND \ (i915_seqno_passed(ring->get_seqno(ring, false), seqno) || \ i915_reset_in_progress(&dev_priv->gpu_error) || \ reset_counter != atomic_read(&dev_priv->gpu_error.reset_counter)) do { if (interruptible) end = wait_event_interruptible_timeout(ring->irq_queue, EXIT_COND, timeout_jiffies); else end = wait_event_timeout(ring->irq_queue, EXIT_COND, timeout_jiffies); /* We need to check whether any gpu reset happened in between * the caller grabbing the seqno and now ... */ if (reset_counter != atomic_read(&dev_priv->gpu_error.reset_counter)) end = -EAGAIN; /* ... but upgrade the -EGAIN to an -EIO if the gpu is truely * gone. */ ret = i915_gem_check_wedge(&dev_priv->gpu_error, interruptible); if (ret) end = ret; } while (end == 0 && wait_forever); getrawmonotonic(&now); ring->irq_put(ring); trace_i915_gem_request_wait_end(ring, seqno); #undef EXIT_COND if (timeout) { struct timespec sleep_time = timespec_sub(now, before); *timeout = timespec_sub(*timeout, sleep_time); if (!timespec_valid(timeout)) /* i.e. negative time remains */ set_normalized_timespec(timeout, 0, 0); } switch (end) { case -EIO: case -EAGAIN: /* Wedged */ case -ERESTARTSYS: /* Signal */ return (int)end; case 0: /* Timeout */ return -ETIME; default: /* Completed */ WARN_ON(end < 0); /* We're not aware of other errors */ return 0; } } /** * Waits for a sequence number to be signaled, and cleans up the * request and object lists appropriately for that event. */ int i915_wait_seqno(struct intel_ring_buffer *ring, uint32_t seqno) { struct drm_device *dev = ring->dev; struct drm_i915_private *dev_priv = dev->dev_private; bool interruptible = dev_priv->mm.interruptible; int ret; BUG_ON(!mutex_is_locked(&dev->struct_mutex)); BUG_ON(seqno == 0); ret = i915_gem_check_wedge(&dev_priv->gpu_error, interruptible); if (ret) return ret; ret = i915_gem_check_olr(ring, seqno); if (ret) return ret; return __wait_seqno(ring, seqno, atomic_read(&dev_priv->gpu_error.reset_counter), interruptible, NULL); } static int i915_gem_object_wait_rendering__tail(struct drm_i915_gem_object *obj, struct intel_ring_buffer *ring) { i915_gem_retire_requests_ring(ring); /* Manually manage the write flush as we may have not yet * retired the buffer. * * Note that the last_write_seqno is always the earlier of * the two (read/write) seqno, so if we haved successfully waited, * we know we have passed the last write. */ obj->last_write_seqno = 0; obj->base.write_domain &= ~I915_GEM_GPU_DOMAINS; return 0; } /** * Ensures that all rendering to the object has completed and the object is * safe to unbind from the GTT or access from the CPU. */ static __must_check int i915_gem_object_wait_rendering(struct drm_i915_gem_object *obj, bool readonly) { struct intel_ring_buffer *ring = obj->ring; u32 seqno; int ret; seqno = readonly ? obj->last_write_seqno : obj->last_read_seqno; if (seqno == 0) return 0; ret = i915_wait_seqno(ring, seqno); if (ret) return ret; return i915_gem_object_wait_rendering__tail(obj, ring); } /* A nonblocking variant of the above wait. This is a highly dangerous routine * as the object state may change during this call. */ static __must_check int i915_gem_object_wait_rendering__nonblocking(struct drm_i915_gem_object *obj, bool readonly) { struct drm_device *dev = obj->base.dev; struct drm_i915_private *dev_priv = dev->dev_private; struct intel_ring_buffer *ring = obj->ring; unsigned reset_counter; u32 seqno; int ret; BUG_ON(!mutex_is_locked(&dev->struct_mutex)); BUG_ON(!dev_priv->mm.interruptible); seqno = readonly ? obj->last_write_seqno : obj->last_read_seqno; if (seqno == 0) return 0; ret = i915_gem_check_wedge(&dev_priv->gpu_error, true); if (ret) return ret; ret = i915_gem_check_olr(ring, seqno); if (ret) return ret; reset_counter = atomic_read(&dev_priv->gpu_error.reset_counter); mutex_unlock(&dev->struct_mutex); ret = __wait_seqno(ring, seqno, reset_counter, true, NULL); mutex_lock(&dev->struct_mutex); if (ret) return ret; return i915_gem_object_wait_rendering__tail(obj, ring); } /** * Called when user space prepares to use an object with the CPU, either * through the mmap ioctl's mapping or a GTT mapping. */ 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 ret; /* Only handle setting domains to types used by the CPU. */ if (write_domain & I915_GEM_GPU_DOMAINS) return -EINVAL; if (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; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } /* 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. */ ret = i915_gem_object_wait_rendering__nonblocking(obj, !write_domain); if (ret) goto unref; if (read_domains & I915_GEM_DOMAIN_GTT) { ret = i915_gem_object_set_to_gtt_domain(obj, write_domain != 0); /* Silently promote "you're not bound, there was nothing to do" * to success, since the client was just asking us to * make sure everything was done. */ if (ret == -EINVAL) ret = 0; } else { ret = i915_gem_object_set_to_cpu_domain(obj, write_domain != 0); } unref: drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } /** * Called when user space has done writes to this buffer */ 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; int ret = 0; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } /* Pinned buffers may be scanout, so flush the cache */ if (obj->pin_count) i915_gem_object_flush_cpu_write_domain(obj); drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } /** * Maps the contents of an object, returning the address it is mapped * into. * * While the mapping holds a reference on the contents of the object, it doesn't * imply a ref on the object itself. */ int i915_gem_mmap_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_mmap *args = data; struct drm_gem_object *obj; unsigned long addr; obj = drm_gem_object_lookup(dev, file, args->handle); if (obj == NULL) return -ENOENT; /* prime objects have no backing filp to GEM mmap * pages from. */ if (!obj->filp) { drm_gem_object_unreference_unlocked(obj); return -EINVAL; } addr = vm_mmap(obj->filp, 0, args->size, PROT_READ | PROT_WRITE, MAP_SHARED, args->offset); drm_gem_object_unreference_unlocked(obj); if (IS_ERR((void *)addr)) return addr; args->addr_ptr = (uint64_t) addr; return 0; } /** * i915_gem_fault - fault a page into the GTT * vma: VMA in question * 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. */ int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { struct drm_i915_gem_object *obj = to_intel_bo(vma->vm_private_data); struct drm_device *dev = obj->base.dev; drm_i915_private_t *dev_priv = dev->dev_private; pgoff_t page_offset; unsigned long pfn; int ret = 0; bool write = !!(vmf->flags & FAULT_FLAG_WRITE); /* We don't use vmf->pgoff since that has the fake offset */ page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >> PAGE_SHIFT; ret = i915_mutex_lock_interruptible(dev); if (ret) goto out; trace_i915_gem_object_fault(obj, page_offset, true, write); /* Access to snoopable pages through the GTT is incoherent. */ if (obj->cache_level != I915_CACHE_NONE && !HAS_LLC(dev)) { ret = -EINVAL; goto unlock; } /* Now bind it into the GTT if needed */ ret = i915_gem_object_pin(obj, 0, true, false); if (ret) goto unlock; ret = i915_gem_object_set_to_gtt_domain(obj, write); if (ret) goto unpin; ret = i915_gem_object_get_fence(obj); if (ret) goto unpin; obj->fault_mappable = true; pfn = ((dev_priv->gtt.mappable_base + obj->gtt_offset) >> PAGE_SHIFT) + page_offset; /* Finally, remap it using the new GTT offset */ ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn); unpin: i915_gem_object_unpin(obj); unlock: mutex_unlock(&dev->struct_mutex); out: switch (ret) { case -EIO: /* If this -EIO is due to a gpu hang, give the reset code a * chance to clean up the mess. Otherwise return the proper * SIGBUS. */ if (i915_terminally_wedged(&dev_priv->gpu_error)) return VM_FAULT_SIGBUS; case -EAGAIN: /* Give the error handler a chance to run and move the * objects off the GPU active list. Next time we service the * fault, we should be able to transition the page into the * GTT without touching the GPU (and so avoid further * EIO/EGAIN). If the GPU is wedged, then there is no issue * with coherency, just lost writes. */ set_need_resched(); case 0: case -ERESTARTSYS: case -EINTR: case -EBUSY: /* * EBUSY is ok: this just means that another thread * already did the job. */ return VM_FAULT_NOPAGE; case -ENOMEM: return VM_FAULT_OOM; case -ENOSPC: return VM_FAULT_SIGBUS; default: WARN_ONCE(ret, "unhandled error in i915_gem_fault: %i\n", ret); return VM_FAULT_SIGBUS; } } /** * 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) { if (!obj->fault_mappable) return; if (obj->base.dev->dev_mapping) unmap_mapping_range(obj->base.dev->dev_mapping, (loff_t)obj->base.map_list.hash.key<base.size, 1); obj->fault_mappable = false; } uint32_t i915_gem_get_gtt_size(struct drm_device *dev, uint32_t size, int tiling_mode) { uint32_t gtt_size; if (INTEL_INFO(dev)->gen >= 4 || tiling_mode == I915_TILING_NONE) return size; /* Previous chips need a power-of-two fence region when tiling */ if (INTEL_INFO(dev)->gen == 3) gtt_size = 1024*1024; else gtt_size = 512*1024; while (gtt_size < size) gtt_size <<= 1; return gtt_size; } /** * i915_gem_get_gtt_alignment - return required GTT alignment for an object * @obj: object to check * * Return the required GTT alignment for an object, taking into account * potential fence register mapping. */ uint32_t i915_gem_get_gtt_alignment(struct drm_device *dev, uint32_t size, int tiling_mode, bool fenced) { /* * Minimum alignment is 4k (GTT page size), but might be greater * if a fence register is needed for the object. */ if (INTEL_INFO(dev)->gen >= 4 || (!fenced && IS_G33(dev)) || tiling_mode == I915_TILING_NONE) return 4096; /* * Previous chips need to be aligned to the size of the smallest * fence register that can contain the object. */ return i915_gem_get_gtt_size(dev, size, tiling_mode); } static int i915_gem_object_create_mmap_offset(struct drm_i915_gem_object *obj) { struct drm_i915_private *dev_priv = obj->base.dev->dev_private; int ret; if (obj->base.map_list.map) return 0; dev_priv->mm.shrinker_no_lock_stealing = true; ret = drm_gem_create_mmap_offset(&obj->base); if (ret != -ENOSPC) goto out; /* Badly fragmented mmap space? The only way we can recover * space is by destroying unwanted objects. We can't randomly release * mmap_offsets as userspace expects them to be persistent for the * lifetime of the objects. The closest we can is to release the * offsets on purgeable objects by truncating it and marking it purged, * which prevents userspace from ever using that object again. */ i915_gem_purge(dev_priv, obj->base.size >> PAGE_SHIFT); ret = drm_gem_create_mmap_offset(&obj->base); if (ret != -ENOSPC) goto out; i915_gem_shrink_all(dev_priv); ret = drm_gem_create_mmap_offset(&obj->base); out: dev_priv->mm.shrinker_no_lock_stealing = false; return ret; } static void i915_gem_object_free_mmap_offset(struct drm_i915_gem_object *obj) { if (!obj->base.map_list.map) return; 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_private *dev_priv = dev->dev_private; struct drm_i915_gem_object *obj; int ret; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } if (obj->base.size > dev_priv->gtt.mappable_end) { ret = -E2BIG; goto out; } if (obj->madv != I915_MADV_WILLNEED) { DRM_ERROR("Attempting to mmap a purgeable buffer\n"); ret = -EINVAL; goto out; } ret = i915_gem_object_create_mmap_offset(obj); if (ret) goto out; *offset = (u64)obj->base.map_list.hash.key << PAGE_SHIFT; out: drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); 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) { struct inode *inode; 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*. */ inode = file_inode(obj->base.filp); shmem_truncate_range(inode, 0, (loff_t)-1); obj->madv = __I915_MADV_PURGED; } static inline int i915_gem_object_is_purgeable(struct drm_i915_gem_object *obj) { return obj->madv == I915_MADV_DONTNEED; } static void i915_gem_object_put_pages_gtt(struct drm_i915_gem_object *obj) { struct sg_page_iter sg_iter; int ret; BUG_ON(obj->madv == __I915_MADV_PURGED); ret = i915_gem_object_set_to_cpu_domain(obj, true); if (ret) { /* In the event of a disaster, abandon all caches and * hope for the best. */ WARN_ON(ret != -EIO); i915_gem_clflush_object(obj); obj->base.read_domains = obj->base.write_domain = I915_GEM_DOMAIN_CPU; } if (i915_gem_object_needs_bit17_swizzle(obj)) i915_gem_object_save_bit_17_swizzle(obj); if (obj->madv == I915_MADV_DONTNEED) obj->dirty = 0; for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0) { struct page *page = sg_page_iter_page(&sg_iter); if (obj->dirty) set_page_dirty(page); if (obj->madv == I915_MADV_WILLNEED) mark_page_accessed(page); page_cache_release(page); } obj->dirty = 0; sg_free_table(obj->pages); kfree(obj->pages); } int i915_gem_object_put_pages(struct drm_i915_gem_object *obj) { const struct drm_i915_gem_object_ops *ops = obj->ops; if (obj->pages == NULL) return 0; BUG_ON(obj->gtt_space); if (obj->pages_pin_count) return -EBUSY; /* ->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. */ list_del(&obj->global_list); ops->put_pages(obj); obj->pages = NULL; if (i915_gem_object_is_purgeable(obj)) i915_gem_object_truncate(obj); return 0; } static long __i915_gem_shrink(struct drm_i915_private *dev_priv, long target, bool purgeable_only) { struct drm_i915_gem_object *obj, *next; long count = 0; list_for_each_entry_safe(obj, next, &dev_priv->mm.unbound_list, global_list) { if ((i915_gem_object_is_purgeable(obj) || !purgeable_only) && i915_gem_object_put_pages(obj) == 0) { count += obj->base.size >> PAGE_SHIFT; if (count >= target) return count; } } list_for_each_entry_safe(obj, next, &dev_priv->mm.inactive_list, mm_list) { if ((i915_gem_object_is_purgeable(obj) || !purgeable_only) && i915_gem_object_unbind(obj) == 0 && i915_gem_object_put_pages(obj) == 0) { count += obj->base.size >> PAGE_SHIFT; if (count >= target) return count; } } return count; } static long i915_gem_purge(struct drm_i915_private *dev_priv, long target) { return __i915_gem_shrink(dev_priv, target, true); } static void i915_gem_shrink_all(struct drm_i915_private *dev_priv) { struct drm_i915_gem_object *obj, *next; i915_gem_evict_everything(dev_priv->dev); list_for_each_entry_safe(obj, next, &dev_priv->mm.unbound_list, global_list) i915_gem_object_put_pages(obj); } static int i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj) { struct drm_i915_private *dev_priv = obj->base.dev->dev_private; int page_count, i; struct address_space *mapping; struct sg_table *st; struct scatterlist *sg; struct sg_page_iter sg_iter; struct page *page; unsigned long last_pfn = 0; /* suppress gcc warning */ gfp_t gfp; /* 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 */ BUG_ON(obj->base.read_domains & I915_GEM_GPU_DOMAINS); BUG_ON(obj->base.write_domain & I915_GEM_GPU_DOMAINS); st = kmalloc(sizeof(*st), GFP_KERNEL); if (st == NULL) return -ENOMEM; page_count = obj->base.size / PAGE_SIZE; if (sg_alloc_table(st, page_count, GFP_KERNEL)) { sg_free_table(st); 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 = file_inode(obj->base.filp)->i_mapping; gfp = mapping_gfp_mask(mapping); gfp |= __GFP_NORETRY | __GFP_NOWARN | __GFP_NO_KSWAPD; gfp &= ~(__GFP_IO | __GFP_WAIT); sg = st->sgl; st->nents = 0; for (i = 0; i < page_count; i++) { page = shmem_read_mapping_page_gfp(mapping, i, gfp); if (IS_ERR(page)) { i915_gem_purge(dev_priv, page_count); page = shmem_read_mapping_page_gfp(mapping, i, gfp); } if (IS_ERR(page)) { /* 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. */ gfp &= ~(__GFP_NORETRY | __GFP_NOWARN | __GFP_NO_KSWAPD); gfp |= __GFP_IO | __GFP_WAIT; i915_gem_shrink_all(dev_priv); page = shmem_read_mapping_page_gfp(mapping, i, gfp); if (IS_ERR(page)) goto err_pages; gfp |= __GFP_NORETRY | __GFP_NOWARN | __GFP_NO_KSWAPD; gfp &= ~(__GFP_IO | __GFP_WAIT); } #ifdef CONFIG_SWIOTLB if (swiotlb_nr_tbl()) { st->nents++; sg_set_page(sg, page, PAGE_SIZE, 0); sg = sg_next(sg); continue; } #endif if (!i || page_to_pfn(page) != last_pfn + 1) { if (i) 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); } #ifdef CONFIG_SWIOTLB if (!swiotlb_nr_tbl()) #endif sg_mark_end(sg); obj->pages = st; if (i915_gem_object_needs_bit17_swizzle(obj)) i915_gem_object_do_bit_17_swizzle(obj); return 0; err_pages: sg_mark_end(sg); for_each_sg_page(st->sgl, &sg_iter, st->nents, 0) page_cache_release(sg_page_iter_page(&sg_iter)); sg_free_table(st); kfree(st); return PTR_ERR(page); } /* Ensure that the associated pages are gathered from the backing storage * and pinned into our object. i915_gem_object_get_pages() may be called * multiple times before they are released by a single call to * i915_gem_object_put_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) { struct drm_i915_private *dev_priv = obj->base.dev->dev_private; const struct drm_i915_gem_object_ops *ops = obj->ops; int ret; if (obj->pages) return 0; if (obj->madv != I915_MADV_WILLNEED) { DRM_ERROR("Attempting to obtain a purgeable object\n"); return -EINVAL; } BUG_ON(obj->pages_pin_count); ret = ops->get_pages(obj); if (ret) return ret; list_add_tail(&obj->global_list, &dev_priv->mm.unbound_list); return 0; } void i915_gem_object_move_to_active(struct drm_i915_gem_object *obj, struct intel_ring_buffer *ring) { struct drm_device *dev = obj->base.dev; struct drm_i915_private *dev_priv = dev->dev_private; u32 seqno = intel_ring_get_seqno(ring); BUG_ON(ring == NULL); obj->ring = ring; /* Add a reference if we're newly entering the active list. */ if (!obj->active) { drm_gem_object_reference(&obj->base); obj->active = 1; } /* Move from whatever list we were on to the tail of execution. */ list_move_tail(&obj->mm_list, &dev_priv->mm.active_list); list_move_tail(&obj->ring_list, &ring->active_list); obj->last_read_seqno = seqno; if (obj->fenced_gpu_access) { obj->last_fenced_seqno = seqno; /* Bump MRU to take account of the delayed flush */ if (obj->fence_reg != I915_FENCE_REG_NONE) { struct drm_i915_fence_reg *reg; reg = &dev_priv->fence_regs[obj->fence_reg]; list_move_tail(®->lru_list, &dev_priv->mm.fence_list); } } } static void i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj) { struct drm_device *dev = obj->base.dev; struct drm_i915_private *dev_priv = dev->dev_private; BUG_ON(obj->base.write_domain & ~I915_GEM_GPU_DOMAINS); BUG_ON(!obj->active); list_move_tail(&obj->mm_list, &dev_priv->mm.inactive_list); list_del_init(&obj->ring_list); obj->ring = NULL; obj->last_read_seqno = 0; obj->last_write_seqno = 0; obj->base.write_domain = 0; obj->last_fenced_seqno = 0; obj->fenced_gpu_access = false; obj->active = 0; drm_gem_object_unreference(&obj->base); WARN_ON(i915_verify_lists(dev)); } static int i915_gem_init_seqno(struct drm_device *dev, u32 seqno) { struct drm_i915_private *dev_priv = dev->dev_private; struct intel_ring_buffer *ring; int ret, i, j; /* Carefully retire all requests without writing to the rings */ for_each_ring(ring, dev_priv, i) { ret = intel_ring_idle(ring); if (ret) return ret; } i915_gem_retire_requests(dev); /* Finally reset hw state */ for_each_ring(ring, dev_priv, i) { intel_ring_init_seqno(ring, seqno); for (j = 0; j < ARRAY_SIZE(ring->sync_seqno); j++) ring->sync_seqno[j] = 0; } return 0; } int i915_gem_set_seqno(struct drm_device *dev, u32 seqno) { struct drm_i915_private *dev_priv = dev->dev_private; int ret; if (seqno == 0) return -EINVAL; /* HWS page needs to be set less than what we * will inject to ring */ ret = i915_gem_init_seqno(dev, seqno - 1); if (ret) return ret; /* Carefully set the last_seqno value so that wrap * detection still works */ dev_priv->next_seqno = seqno; dev_priv->last_seqno = seqno - 1; if (dev_priv->last_seqno == 0) dev_priv->last_seqno--; return 0; } int i915_gem_get_seqno(struct drm_device *dev, u32 *seqno) { struct drm_i915_private *dev_priv = dev->dev_private; /* reserve 0 for non-seqno */ if (dev_priv->next_seqno == 0) { int ret = i915_gem_init_seqno(dev, 0); if (ret) return ret; dev_priv->next_seqno = 1; } *seqno = dev_priv->last_seqno = dev_priv->next_seqno++; return 0; } int __i915_add_request(struct intel_ring_buffer *ring, struct drm_file *file, struct drm_i915_gem_object *obj, u32 *out_seqno) { drm_i915_private_t *dev_priv = ring->dev->dev_private; struct drm_i915_gem_request *request; u32 request_ring_position, request_start; int was_empty; int ret; request_start = intel_ring_get_tail(ring); /* * Emit any outstanding flushes - execbuf can fail to emit the flush * after having emitted the batchbuffer command. Hence we need to fix * things up similar to emitting the lazy request. The difference here * is that the flush _must_ happen before the next request, no matter * what. */ ret = intel_ring_flush_all_caches(ring); if (ret) return ret; request = kmalloc(sizeof(*request), GFP_KERNEL); if (request == NULL) return -ENOMEM; /* Record the position of the start of the request so that * should we detect the updated seqno part-way through the * GPU processing the request, we never over-estimate the * position of the head. */ request_ring_position = intel_ring_get_tail(ring); ret = ring->add_request(ring); if (ret) { kfree(request); return ret; } request->seqno = intel_ring_get_seqno(ring); request->ring = ring; request->head = request_start; request->tail = request_ring_position; request->ctx = ring->last_context; request->batch_obj = obj; /* Whilst this request exists, batch_obj will be on the * active_list, and so will hold the active reference. Only when this * request is retired will the the batch_obj be moved onto the * inactive_list and lose its active reference. Hence we do not need * to explicitly hold another reference here. */ if (request->ctx) i915_gem_context_reference(request->ctx); request->emitted_jiffies = jiffies; was_empty = list_empty(&ring->request_list); list_add_tail(&request->list, &ring->request_list); request->file_priv = NULL; if (file) { struct drm_i915_file_private *file_priv = file->driver_priv; spin_lock(&file_priv->mm.lock); request->file_priv = file_priv; list_add_tail(&request->client_list, &file_priv->mm.request_list); spin_unlock(&file_priv->mm.lock); } trace_i915_gem_request_add(ring, request->seqno); ring->outstanding_lazy_request = 0; if (!dev_priv->mm.suspended) { if (i915_enable_hangcheck) { mod_timer(&dev_priv->gpu_error.hangcheck_timer, round_jiffies_up(jiffies + DRM_I915_HANGCHECK_JIFFIES)); } if (was_empty) { queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, round_jiffies_up_relative(HZ)); intel_mark_busy(dev_priv->dev); } } if (out_seqno) *out_seqno = request->seqno; return 0; } static inline void i915_gem_request_remove_from_client(struct drm_i915_gem_request *request) { struct drm_i915_file_private *file_priv = request->file_priv; if (!file_priv) return; spin_lock(&file_priv->mm.lock); if (request->file_priv) { list_del(&request->client_list); request->file_priv = NULL; } spin_unlock(&file_priv->mm.lock); } static bool i915_head_inside_object(u32 acthd, struct drm_i915_gem_object *obj) { if (acthd >= obj->gtt_offset && acthd < obj->gtt_offset + obj->base.size) return true; return false; } static bool i915_head_inside_request(const u32 acthd_unmasked, const u32 request_start, const u32 request_end) { const u32 acthd = acthd_unmasked & HEAD_ADDR; if (request_start < request_end) { if (acthd >= request_start && acthd < request_end) return true; } else if (request_start > request_end) { if (acthd >= request_start || acthd < request_end) return true; } return false; } static bool i915_request_guilty(struct drm_i915_gem_request *request, const u32 acthd, bool *inside) { /* There is a possibility that unmasked head address * pointing inside the ring, matches the batch_obj address range. * However this is extremely unlikely. */ if (request->batch_obj) { if (i915_head_inside_object(acthd, request->batch_obj)) { *inside = true; return true; } } if (i915_head_inside_request(acthd, request->head, request->tail)) { *inside = false; return true; } return false; } static void i915_set_reset_status(struct intel_ring_buffer *ring, struct drm_i915_gem_request *request, u32 acthd) { struct i915_ctx_hang_stats *hs = NULL; bool inside, guilty; /* Innocent until proven guilty */ guilty = false; if (ring->hangcheck.action != wait && i915_request_guilty(request, acthd, &inside)) { DRM_ERROR("%s hung %s bo (0x%x ctx %d) at 0x%x\n", ring->name, inside ? "inside" : "flushing", request->batch_obj ? request->batch_obj->gtt_offset : 0, request->ctx ? request->ctx->id : 0, acthd); guilty = true; } /* If contexts are disabled or this is the default context, use * file_priv->reset_state */ if (request->ctx && request->ctx->id != DEFAULT_CONTEXT_ID) hs = &request->ctx->hang_stats; else if (request->file_priv) hs = &request->file_priv->hang_stats; if (hs) { if (guilty) hs->batch_active++; else hs->batch_pending++; } } static void i915_gem_free_request(struct drm_i915_gem_request *request) { list_del(&request->list); i915_gem_request_remove_from_client(request); if (request->ctx) i915_gem_context_unreference(request->ctx); kfree(request); } static void i915_gem_reset_ring_lists(struct drm_i915_private *dev_priv, struct intel_ring_buffer *ring) { u32 completed_seqno; u32 acthd; acthd = intel_ring_get_active_head(ring); completed_seqno = ring->get_seqno(ring, false); while (!list_empty(&ring->request_list)) { struct drm_i915_gem_request *request; request = list_first_entry(&ring->request_list, struct drm_i915_gem_request, list); if (request->seqno > completed_seqno) i915_set_reset_status(ring, request, acthd); i915_gem_free_request(request); } while (!list_empty(&ring->active_list)) { struct drm_i915_gem_object *obj; obj = list_first_entry(&ring->active_list, struct drm_i915_gem_object, ring_list); i915_gem_object_move_to_inactive(obj); } } static void i915_gem_reset_fences(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; int i; for (i = 0; i < dev_priv->num_fence_regs; i++) { struct drm_i915_fence_reg *reg = &dev_priv->fence_regs[i]; if (reg->obj) i915_gem_object_fence_lost(reg->obj); i915_gem_write_fence(dev, i, NULL); reg->pin_count = 0; reg->obj = NULL; INIT_LIST_HEAD(®->lru_list); } INIT_LIST_HEAD(&dev_priv->mm.fence_list); } void i915_gem_reset(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_object *obj; struct intel_ring_buffer *ring; int i; for_each_ring(ring, dev_priv, i) i915_gem_reset_ring_lists(dev_priv, ring); /* Move everything out of the GPU domains to ensure we do any * necessary invalidation upon reuse. */ list_for_each_entry(obj, &dev_priv->mm.inactive_list, mm_list) { obj->base.read_domains &= ~I915_GEM_GPU_DOMAINS; } /* The fence registers are invalidated so clear them out */ i915_gem_reset_fences(dev); } /** * This function clears the request list as sequence numbers are passed. */ void i915_gem_retire_requests_ring(struct intel_ring_buffer *ring) { uint32_t seqno; if (list_empty(&ring->request_list)) return; WARN_ON(i915_verify_lists(ring->dev)); seqno = ring->get_seqno(ring, true); while (!list_empty(&ring->request_list)) { struct drm_i915_gem_request *request; request = list_first_entry(&ring->request_list, struct drm_i915_gem_request, list); if (!i915_seqno_passed(seqno, request->seqno)) break; trace_i915_gem_request_retire(ring, request->seqno); /* We know the GPU must have read the request to have * sent us the seqno + interrupt, so use the position * of tail of the request to update the last known position * of the GPU head. */ ring->last_retired_head = request->tail; i915_gem_free_request(request); } /* Move any buffers on the active list that are no longer referenced * by the ringbuffer to the flushing/inactive lists as appropriate. */ while (!list_empty(&ring->active_list)) { struct drm_i915_gem_object *obj; obj = list_first_entry(&ring->active_list, struct drm_i915_gem_object, ring_list); if (!i915_seqno_passed(seqno, obj->last_read_seqno)) break; i915_gem_object_move_to_inactive(obj); } if (unlikely(ring->trace_irq_seqno && i915_seqno_passed(seqno, ring->trace_irq_seqno))) { ring->irq_put(ring); ring->trace_irq_seqno = 0; } WARN_ON(i915_verify_lists(ring->dev)); } void i915_gem_retire_requests(struct drm_device *dev) { drm_i915_private_t *dev_priv = dev->dev_private; struct intel_ring_buffer *ring; int i; for_each_ring(ring, dev_priv, i) i915_gem_retire_requests_ring(ring); } static void i915_gem_retire_work_handler(struct work_struct *work) { drm_i915_private_t *dev_priv; struct drm_device *dev; struct intel_ring_buffer *ring; bool idle; int i; dev_priv = container_of(work, drm_i915_private_t, mm.retire_work.work); dev = dev_priv->dev; /* Come back later if the device is busy... */ if (!mutex_trylock(&dev->struct_mutex)) { queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, round_jiffies_up_relative(HZ)); return; } i915_gem_retire_requests(dev); /* Send a periodic flush down the ring so we don't hold onto GEM * objects indefinitely. */ idle = true; for_each_ring(ring, dev_priv, i) { if (ring->gpu_caches_dirty) i915_add_request(ring, NULL); idle &= list_empty(&ring->request_list); } if (!dev_priv->mm.suspended && !idle) queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, round_jiffies_up_relative(HZ)); if (idle) intel_mark_idle(dev); mutex_unlock(&dev->struct_mutex); } /** * Ensures that an object will eventually get non-busy by flushing any required * write domains, emitting any outstanding lazy request and retiring and * completed requests. */ static int i915_gem_object_flush_active(struct drm_i915_gem_object *obj) { int ret; if (obj->active) { ret = i915_gem_check_olr(obj->ring, obj->last_read_seqno); if (ret) return ret; i915_gem_retire_requests_ring(obj->ring); } return 0; } /** * i915_gem_wait_ioctl - implements DRM_IOCTL_I915_GEM_WAIT * @DRM_IOCTL_ARGS: standard ioctl arguments * * 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: GPU wedged * -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) { drm_i915_private_t *dev_priv = dev->dev_private; struct drm_i915_gem_wait *args = data; struct drm_i915_gem_object *obj; struct intel_ring_buffer *ring = NULL; struct timespec timeout_stack, *timeout = NULL; unsigned reset_counter; u32 seqno = 0; int ret = 0; if (args->timeout_ns >= 0) { timeout_stack = ns_to_timespec(args->timeout_ns); timeout = &timeout_stack; } ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->bo_handle)); if (&obj->base == NULL) { mutex_unlock(&dev->struct_mutex); return -ENOENT; } /* Need to make sure the object gets inactive eventually. */ ret = i915_gem_object_flush_active(obj); if (ret) goto out; if (obj->active) { seqno = obj->last_read_seqno; ring = obj->ring; } if (seqno == 0) goto out; /* Do this after OLR check to make sure we make forward progress polling * on this IOCTL with a 0 timeout (like busy ioctl) */ if (!args->timeout_ns) { ret = -ETIME; goto out; } drm_gem_object_unreference(&obj->base); reset_counter = atomic_read(&dev_priv->gpu_error.reset_counter); mutex_unlock(&dev->struct_mutex); ret = __wait_seqno(ring, seqno, reset_counter, true, timeout); if (timeout) args->timeout_ns = timespec_to_ns(timeout); return ret; out: drm_gem_object_unreference(&obj->base); mutex_unlock(&dev->struct_mutex); return ret; } /** * i915_gem_object_sync - sync an object to a ring. * * @obj: object which may be in use on another ring. * @to: ring we wish to use the object on. May be NULL. * * This code is meant to abstract object synchronization with the GPU. * Calling with NULL implies synchronizing the object with the CPU * rather than a particular GPU ring. * * Returns 0 if successful, else propagates up the lower layer error. */ int i915_gem_object_sync(struct drm_i915_gem_object *obj, struct intel_ring_buffer *to) { struct intel_ring_buffer *from = obj->ring; u32 seqno; int ret, idx; if (from == NULL || to == from) return 0; if (to == NULL || !i915_semaphore_is_enabled(obj->base.dev)) return i915_gem_object_wait_rendering(obj, false); idx = intel_ring_sync_index(from, to); seqno = obj->last_read_seqno; if (seqno <= from->sync_seqno[idx]) return 0; ret = i915_gem_check_olr(obj->ring, seqno); if (ret) return ret; ret = to->sync_to(to, from, seqno); if (!ret) /* We use last_read_seqno because sync_to() * might have just caused seqno wrap under * the radar. */ from->sync_seqno[idx] = obj->last_read_seqno; return ret; } static void i915_gem_object_finish_gtt(struct drm_i915_gem_object *obj) { u32 old_write_domain, old_read_domains; /* Force a pagefault for domain tracking on next user access */ i915_gem_release_mmap(obj); if ((obj->base.read_domains & I915_GEM_DOMAIN_GTT) == 0) return; /* Wait for any direct GTT access to complete */ mb(); old_read_domains = obj->base.read_domains; old_write_domain = obj->base.write_domain; obj->base.read_domains &= ~I915_GEM_DOMAIN_GTT; obj->base.write_domain &= ~I915_GEM_DOMAIN_GTT; trace_i915_gem_object_change_domain(obj, old_read_domains, old_write_domain); } /** * Unbinds an object from the GTT aperture. */ int i915_gem_object_unbind(struct drm_i915_gem_object *obj) { drm_i915_private_t *dev_priv = obj->base.dev->dev_private; int ret; if (obj->gtt_space == NULL) return 0; if (obj->pin_count) return -EBUSY; BUG_ON(obj->pages == NULL); ret = i915_gem_object_finish_gpu(obj); if (ret) return ret; /* Continue on if we fail due to EIO, the GPU is hung so we * should be safe and we need to cleanup or else we might * cause memory corruption through use-after-free. */ i915_gem_object_finish_gtt(obj); /* release the fence reg _after_ flushing */ ret = i915_gem_object_put_fence(obj); if (ret) return ret; trace_i915_gem_object_unbind(obj); if (obj->has_global_gtt_mapping) i915_gem_gtt_unbind_object(obj); if (obj->has_aliasing_ppgtt_mapping) { i915_ppgtt_unbind_object(dev_priv->mm.aliasing_ppgtt, obj); obj->has_aliasing_ppgtt_mapping = 0; } i915_gem_gtt_finish_object(obj); i915_gem_object_unpin_pages(obj); list_del(&obj->mm_list); list_move_tail(&obj->global_list, &dev_priv->mm.unbound_list); /* Avoid an unnecessary call to unbind on rebind. */ obj->map_and_fenceable = true; drm_mm_put_block(obj->gtt_space); obj->gtt_space = NULL; obj->gtt_offset = 0; return 0; } int i915_gpu_idle(struct drm_device *dev) { drm_i915_private_t *dev_priv = dev->dev_private; struct intel_ring_buffer *ring; int ret, i; /* Flush everything onto the inactive list. */ for_each_ring(ring, dev_priv, i) { ret = i915_switch_context(ring, NULL, DEFAULT_CONTEXT_ID); if (ret) return ret; ret = intel_ring_idle(ring); if (ret) return ret; } return 0; } static void i965_write_fence_reg(struct drm_device *dev, int reg, struct drm_i915_gem_object *obj) { drm_i915_private_t *dev_priv = dev->dev_private; int fence_reg; int fence_pitch_shift; uint64_t val; if (INTEL_INFO(dev)->gen >= 6) { fence_reg = FENCE_REG_SANDYBRIDGE_0; fence_pitch_shift = SANDYBRIDGE_FENCE_PITCH_SHIFT; } else { fence_reg = FENCE_REG_965_0; fence_pitch_shift = I965_FENCE_PITCH_SHIFT; } if (obj) { u32 size = obj->gtt_space->size; val = (uint64_t)((obj->gtt_offset + size - 4096) & 0xfffff000) << 32; val |= obj->gtt_offset & 0xfffff000; val |= (uint64_t)((obj->stride / 128) - 1) << fence_pitch_shift; if (obj->tiling_mode == I915_TILING_Y) val |= 1 << I965_FENCE_TILING_Y_SHIFT; val |= I965_FENCE_REG_VALID; } else val = 0; fence_reg += reg * 8; I915_WRITE64(fence_reg, val); POSTING_READ(fence_reg); } static void i915_write_fence_reg(struct drm_device *dev, int reg, struct drm_i915_gem_object *obj) { drm_i915_private_t *dev_priv = dev->dev_private; u32 val; if (obj) { u32 size = obj->gtt_space->size; int pitch_val; int tile_width; WARN((obj->gtt_offset & ~I915_FENCE_START_MASK) || (size & -size) != size || (obj->gtt_offset & (size - 1)), "object 0x%08x [fenceable? %d] not 1M or pot-size (0x%08x) aligned\n", obj->gtt_offset, obj->map_and_fenceable, size); if (obj->tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev)) tile_width = 128; else tile_width = 512; /* Note: pitch better be a power of two tile widths */ pitch_val = obj->stride / tile_width; pitch_val = ffs(pitch_val) - 1; val = obj->gtt_offset; if (obj->tiling_mode == I915_TILING_Y) val |= 1 << I830_FENCE_TILING_Y_SHIFT; val |= I915_FENCE_SIZE_BITS(size); val |= pitch_val << I830_FENCE_PITCH_SHIFT; val |= I830_FENCE_REG_VALID; } else val = 0; if (reg < 8) reg = FENCE_REG_830_0 + reg * 4; else reg = FENCE_REG_945_8 + (reg - 8) * 4; I915_WRITE(reg, val); POSTING_READ(reg); } static void i830_write_fence_reg(struct drm_device *dev, int reg, struct drm_i915_gem_object *obj) { drm_i915_private_t *dev_priv = dev->dev_private; uint32_t val; if (obj) { u32 size = obj->gtt_space->size; uint32_t pitch_val; WARN((obj->gtt_offset & ~I830_FENCE_START_MASK) || (size & -size) != size || (obj->gtt_offset & (size - 1)), "object 0x%08x not 512K or pot-size 0x%08x aligned\n", obj->gtt_offset, size); pitch_val = obj->stride / 128; pitch_val = ffs(pitch_val) - 1; val = obj->gtt_offset; if (obj->tiling_mode == I915_TILING_Y) val |= 1 << I830_FENCE_TILING_Y_SHIFT; val |= I830_FENCE_SIZE_BITS(size); val |= pitch_val << I830_FENCE_PITCH_SHIFT; val |= I830_FENCE_REG_VALID; } else val = 0; I915_WRITE(FENCE_REG_830_0 + reg * 4, val); POSTING_READ(FENCE_REG_830_0 + reg * 4); } inline static bool i915_gem_object_needs_mb(struct drm_i915_gem_object *obj) { return obj && obj->base.read_domains & I915_GEM_DOMAIN_GTT; } static void i915_gem_write_fence(struct drm_device *dev, int reg, struct drm_i915_gem_object *obj) { struct drm_i915_private *dev_priv = dev->dev_private; /* Ensure that all CPU reads are completed before installing a fence * and all writes before removing the fence. */ if (i915_gem_object_needs_mb(dev_priv->fence_regs[reg].obj)) mb(); switch (INTEL_INFO(dev)->gen) { case 7: case 6: case 5: case 4: i965_write_fence_reg(dev, reg, obj); break; case 3: i915_write_fence_reg(dev, reg, obj); break; case 2: i830_write_fence_reg(dev, reg, obj); break; default: BUG(); } /* And similarly be paranoid that no direct access to this region * is reordered to before the fence is installed. */ if (i915_gem_object_needs_mb(obj)) mb(); } static inline int fence_number(struct drm_i915_private *dev_priv, struct drm_i915_fence_reg *fence) { return fence - dev_priv->fence_regs; } struct write_fence { struct drm_device *dev; struct drm_i915_gem_object *obj; int fence; }; static void i915_gem_write_fence__ipi(void *data) { struct write_fence *args = data; /* Required for SNB+ with LLC */ wbinvd(); /* Required for VLV */ i915_gem_write_fence(args->dev, args->fence, args->obj); } static void i915_gem_object_update_fence(struct drm_i915_gem_object *obj, struct drm_i915_fence_reg *fence, bool enable) { struct drm_i915_private *dev_priv = obj->base.dev->dev_private; struct write_fence args = { .dev = obj->base.dev, .fence = fence_number(dev_priv, fence), .obj = enable ? obj : NULL, }; /* In order to fully serialize access to the fenced region and * the update to the fence register we need to take extreme * measures on SNB+. In theory, the write to the fence register * flushes all memory transactions before, and coupled with the * mb() placed around the register write we serialise all memory * operations with respect to the changes in the tiler. Yet, on * SNB+ we need to take a step further and emit an explicit wbinvd() * on each processor in order to manually flush all memory * transactions before updating the fence register. * * However, Valleyview complicates matter. There the wbinvd is * insufficient and unlike SNB/IVB requires the serialising * register write. (Note that that register write by itself is * conversely not sufficient for SNB+.) To compromise, we do both. */ if (INTEL_INFO(args.dev)->gen >= 6) on_each_cpu(i915_gem_write_fence__ipi, &args, 1); else i915_gem_write_fence(args.dev, args.fence, args.obj); if (enable) { obj->fence_reg = args.fence; fence->obj = obj; list_move_tail(&fence->lru_list, &dev_priv->mm.fence_list); } else { obj->fence_reg = I915_FENCE_REG_NONE; fence->obj = NULL; list_del_init(&fence->lru_list); } } static int i915_gem_object_wait_fence(struct drm_i915_gem_object *obj) { if (obj->last_fenced_seqno) { int ret = i915_wait_seqno(obj->ring, obj->last_fenced_seqno); if (ret) return ret; obj->last_fenced_seqno = 0; } obj->fenced_gpu_access = false; return 0; } int i915_gem_object_put_fence(struct drm_i915_gem_object *obj) { struct drm_i915_private *dev_priv = obj->base.dev->dev_private; struct drm_i915_fence_reg *fence; int ret; ret = i915_gem_object_wait_fence(obj); if (ret) return ret; if (obj->fence_reg == I915_FENCE_REG_NONE) return 0; fence = &dev_priv->fence_regs[obj->fence_reg]; i915_gem_object_fence_lost(obj); i915_gem_object_update_fence(obj, fence, false); return 0; } static struct drm_i915_fence_reg * i915_find_fence_reg(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_fence_reg *reg, *avail; int i; /* First try to find a free reg */ avail = NULL; for (i = dev_priv->fence_reg_start; i < dev_priv->num_fence_regs; i++) { reg = &dev_priv->fence_regs[i]; if (!reg->obj) return reg; if (!reg->pin_count) avail = reg; } if (avail == NULL) return NULL; /* None available, try to steal one or wait for a user to finish */ list_for_each_entry(reg, &dev_priv->mm.fence_list, lru_list) { if (reg->pin_count) continue; return reg; } return NULL; } /** * i915_gem_object_get_fence - set up fencing for an object * @obj: object to map through a fence reg * * When mapping objects through the GTT, userspace wants to be able to write * to them without having to worry about swizzling if the object is tiled. * This function walks the fence regs looking for a free one for @obj, * stealing one if it can't find any. * * It then sets up the reg based on the object's properties: address, pitch * and tiling format. * * For an untiled surface, this removes any existing fence. */ int i915_gem_object_get_fence(struct drm_i915_gem_object *obj) { struct drm_device *dev = obj->base.dev; struct drm_i915_private *dev_priv = dev->dev_private; bool enable = obj->tiling_mode != I915_TILING_NONE; struct drm_i915_fence_reg *reg; int ret; /* Have we updated the tiling parameters upon the object and so * will need to serialise the write to the associated fence register? */ if (obj->fence_dirty) { ret = i915_gem_object_wait_fence(obj); if (ret) return ret; } /* Just update our place in the LRU if our fence is getting reused. */ if (obj->fence_reg != I915_FENCE_REG_NONE) { reg = &dev_priv->fence_regs[obj->fence_reg]; if (!obj->fence_dirty) { list_move_tail(®->lru_list, &dev_priv->mm.fence_list); return 0; } } else if (enable) { reg = i915_find_fence_reg(dev); if (reg == NULL) return -EDEADLK; if (reg->obj) { struct drm_i915_gem_object *old = reg->obj; ret = i915_gem_object_wait_fence(old); if (ret) return ret; i915_gem_object_fence_lost(old); } } else return 0; i915_gem_object_update_fence(obj, reg, enable); obj->fence_dirty = false; return 0; } static bool i915_gem_valid_gtt_space(struct drm_device *dev, struct drm_mm_node *gtt_space, unsigned long cache_level) { struct drm_mm_node *other; /* On non-LLC machines we have to be careful when putting differing * types of snoopable memory together to avoid the prefetcher * crossing memory domains and dying. */ if (HAS_LLC(dev)) return true; if (gtt_space == NULL) return true; if (list_empty(>t_space->node_list)) return true; other = list_entry(gtt_space->node_list.prev, struct drm_mm_node, node_list); if (other->allocated && !other->hole_follows && other->color != cache_level) return false; other = list_entry(gtt_space->node_list.next, struct drm_mm_node, node_list); if (other->allocated && !gtt_space->hole_follows && other->color != cache_level) return false; return true; } static void i915_gem_verify_gtt(struct drm_device *dev) { #if WATCH_GTT struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_object *obj; int err = 0; list_for_each_entry(obj, &dev_priv->mm.gtt_list, global_list) { if (obj->gtt_space == NULL) { printk(KERN_ERR "object found on GTT list with no space reserved\n"); err++; continue; } if (obj->cache_level != obj->gtt_space->color) { printk(KERN_ERR "object reserved space [%08lx, %08lx] with wrong color, cache_level=%x, color=%lx\n", obj->gtt_space->start, obj->gtt_space->start + obj->gtt_space->size, obj->cache_level, obj->gtt_space->color); err++; continue; } if (!i915_gem_valid_gtt_space(dev, obj->gtt_space, obj->cache_level)) { printk(KERN_ERR "invalid GTT space found at [%08lx, %08lx] - color=%x\n", obj->gtt_space->start, obj->gtt_space->start + obj->gtt_space->size, obj->cache_level); err++; continue; } } WARN_ON(err); #endif } /** * Finds free space in the GTT aperture and binds the object there. */ static int i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj, unsigned alignment, bool map_and_fenceable, bool nonblocking) { struct drm_device *dev = obj->base.dev; drm_i915_private_t *dev_priv = dev->dev_private; struct drm_mm_node *node; u32 size, fence_size, fence_alignment, unfenced_alignment; bool mappable, fenceable; size_t gtt_max = map_and_fenceable ? dev_priv->gtt.mappable_end : dev_priv->gtt.total; int ret; fence_size = i915_gem_get_gtt_size(dev, obj->base.size, obj->tiling_mode); fence_alignment = i915_gem_get_gtt_alignment(dev, obj->base.size, obj->tiling_mode, true); unfenced_alignment = i915_gem_get_gtt_alignment(dev, obj->base.size, obj->tiling_mode, false); if (alignment == 0) alignment = map_and_fenceable ? fence_alignment : unfenced_alignment; if (map_and_fenceable && alignment & (fence_alignment - 1)) { DRM_ERROR("Invalid object alignment requested %u\n", alignment); return -EINVAL; } size = map_and_fenceable ? fence_size : obj->base.size; /* If the object is bigger than the entire aperture, reject it early * before evicting everything in a vain attempt to find space. */ if (obj->base.size > gtt_max) { DRM_ERROR("Attempting to bind an object larger than the aperture: object=%zd > %s aperture=%zu\n", obj->base.size, map_and_fenceable ? "mappable" : "total", gtt_max); return -E2BIG; } ret = i915_gem_object_get_pages(obj); if (ret) return ret; i915_gem_object_pin_pages(obj); node = kzalloc(sizeof(*node), GFP_KERNEL); if (node == NULL) { i915_gem_object_unpin_pages(obj); return -ENOMEM; } search_free: ret = drm_mm_insert_node_in_range_generic(&dev_priv->mm.gtt_space, node, size, alignment, obj->cache_level, 0, gtt_max); if (ret) { ret = i915_gem_evict_something(dev, size, alignment, obj->cache_level, map_and_fenceable, nonblocking); if (ret == 0) goto search_free; i915_gem_object_unpin_pages(obj); kfree(node); return ret; } if (WARN_ON(!i915_gem_valid_gtt_space(dev, node, obj->cache_level))) { i915_gem_object_unpin_pages(obj); drm_mm_put_block(node); return -EINVAL; } ret = i915_gem_gtt_prepare_object(obj); if (ret) { i915_gem_object_unpin_pages(obj); drm_mm_put_block(node); return ret; } list_move_tail(&obj->global_list, &dev_priv->mm.bound_list); list_add_tail(&obj->mm_list, &dev_priv->mm.inactive_list); obj->gtt_space = node; obj->gtt_offset = node->start; fenceable = node->size == fence_size && (node->start & (fence_alignment - 1)) == 0; mappable = obj->gtt_offset + obj->base.size <= dev_priv->gtt.mappable_end; obj->map_and_fenceable = mappable && fenceable; trace_i915_gem_object_bind(obj, map_and_fenceable); i915_gem_verify_gtt(dev); return 0; } void i915_gem_clflush_object(struct drm_i915_gem_object *obj) { /* If we don't have a page list set up, then we're not pinned * to GPU, and we can ignore the cache flush because it'll happen * again at bind time. */ if (obj->pages == NULL) return; /* * Stolen memory is always coherent with the GPU as it is explicitly * marked as wc by the system, or the system is cache-coherent. */ if (obj->stolen) return; /* If the GPU is snooping the contents of the CPU cache, * we do not need to manually clear the CPU cache lines. However, * the caches are only snooped when the render cache is * flushed/invalidated. As we always have to emit invalidations * and flushes when moving into and out of the RENDER domain, correct * snooping behaviour occurs naturally as the result of our domain * tracking. */ if (obj->cache_level != I915_CACHE_NONE) return; trace_i915_gem_object_clflush(obj); drm_clflush_sg(obj->pages); } /** Flushes the GTT write domain for the object if it's dirty. */ static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj) { uint32_t old_write_domain; if (obj->base.write_domain != I915_GEM_DOMAIN_GTT) 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. */ wmb(); old_write_domain = obj->base.write_domain; obj->base.write_domain = 0; trace_i915_gem_object_change_domain(obj, obj->base.read_domains, old_write_domain); } /** Flushes the CPU write domain for the object if it's dirty. */ static void i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj) { uint32_t old_write_domain; if (obj->base.write_domain != I915_GEM_DOMAIN_CPU) return; i915_gem_clflush_object(obj); i915_gem_chipset_flush(obj->base.dev); old_write_domain = obj->base.write_domain; obj->base.write_domain = 0; trace_i915_gem_object_change_domain(obj, obj->base.read_domains, old_write_domain); } /** * Moves a single object to the GTT read, and possibly write domain. * * 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) { drm_i915_private_t *dev_priv = obj->base.dev->dev_private; uint32_t old_write_domain, old_read_domains; int ret; /* Not valid to be called on unbound objects. */ if (obj->gtt_space == NULL) return -EINVAL; if (obj->base.write_domain == I915_GEM_DOMAIN_GTT) return 0; ret = i915_gem_object_wait_rendering(obj, !write); if (ret) return ret; i915_gem_object_flush_cpu_write_domain(obj); /* 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(); old_write_domain = obj->base.write_domain; old_read_domains = obj->base.read_domains; /* It should now be out of any other write domains, and we can update * the domain values for our changes. */ 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->dirty = 1; } trace_i915_gem_object_change_domain(obj, old_read_domains, old_write_domain); /* And bump the LRU for this access */ if (i915_gem_object_is_inactive(obj)) list_move_tail(&obj->mm_list, &dev_priv->mm.inactive_list); return 0; } int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj, enum i915_cache_level cache_level) { struct drm_device *dev = obj->base.dev; drm_i915_private_t *dev_priv = dev->dev_private; int ret; if (obj->cache_level == cache_level) return 0; if (obj->pin_count) { DRM_DEBUG("can not change the cache level of pinned objects\n"); return -EBUSY; } if (!i915_gem_valid_gtt_space(dev, obj->gtt_space, cache_level)) { ret = i915_gem_object_unbind(obj); if (ret) return ret; } if (obj->gtt_space) { ret = i915_gem_object_finish_gpu(obj); if (ret) return ret; i915_gem_object_finish_gtt(obj); /* Before SandyBridge, you could not use tiling or fence * registers with snooped memory, so relinquish any fences * currently pointing to our region in the aperture. */ if (INTEL_INFO(dev)->gen < 6) { ret = i915_gem_object_put_fence(obj); if (ret) return ret; } if (obj->has_global_gtt_mapping) i915_gem_gtt_bind_object(obj, cache_level); if (obj->has_aliasing_ppgtt_mapping) i915_ppgtt_bind_object(dev_priv->mm.aliasing_ppgtt, obj, cache_level); obj->gtt_space->color = cache_level; } if (cache_level == I915_CACHE_NONE) { u32 old_read_domains, old_write_domain; /* If we're coming from LLC cached, then we haven't * actually been tracking whether the data is in the * CPU cache or not, since we only allow one bit set * in obj->write_domain and have been skipping the clflushes. * Just set it to the CPU cache for now. */ WARN_ON(obj->base.write_domain & ~I915_GEM_DOMAIN_CPU); WARN_ON(obj->base.read_domains & ~I915_GEM_DOMAIN_CPU); old_read_domains = obj->base.read_domains; old_write_domain = obj->base.write_domain; obj->base.read_domains = I915_GEM_DOMAIN_CPU; obj->base.write_domain = I915_GEM_DOMAIN_CPU; trace_i915_gem_object_change_domain(obj, old_read_domains, old_write_domain); } obj->cache_level = cache_level; i915_gem_verify_gtt(dev); 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 ret; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } args->caching = obj->cache_level != I915_CACHE_NONE; drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } int i915_gem_set_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; enum i915_cache_level level; int ret; switch (args->caching) { case I915_CACHING_NONE: level = I915_CACHE_NONE; break; case I915_CACHING_CACHED: level = I915_CACHE_LLC; break; default: return -EINVAL; } ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } ret = i915_gem_object_set_cache_level(obj, level); drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); 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). */ int i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj, u32 alignment, struct intel_ring_buffer *pipelined) { u32 old_read_domains, old_write_domain; int ret; if (pipelined != obj->ring) { ret = i915_gem_object_sync(obj, pipelined); if (ret) return ret; } /* 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, I915_CACHE_NONE); if (ret) return ret; /* 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. */ ret = i915_gem_object_pin(obj, alignment, true, false); if (ret) return ret; i915_gem_object_flush_cpu_write_domain(obj); old_write_domain = obj->base.write_domain; old_read_domains = obj->base.read_domains; /* It should now be out of any other write domains, and we can update * the domain values for our changes. */ obj->base.write_domain = 0; obj->base.read_domains |= I915_GEM_DOMAIN_GTT; trace_i915_gem_object_change_domain(obj, old_read_domains, old_write_domain); return 0; } int i915_gem_object_finish_gpu(struct drm_i915_gem_object *obj) { int ret; if ((obj->base.read_domains & I915_GEM_GPU_DOMAINS) == 0) return 0; ret = i915_gem_object_wait_rendering(obj, false); if (ret) return ret; /* Ensure that we invalidate the GPU's caches and TLBs. */ obj->base.read_domains &= ~I915_GEM_GPU_DOMAINS; return 0; } /** * Moves a single object to the CPU read, and possibly write domain. * * 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) { uint32_t old_write_domain, old_read_domains; int ret; if (obj->base.write_domain == I915_GEM_DOMAIN_CPU) return 0; ret = i915_gem_object_wait_rendering(obj, !write); if (ret) return ret; i915_gem_object_flush_gtt_write_domain(obj); old_write_domain = obj->base.write_domain; old_read_domains = obj->base.read_domains; /* Flush the CPU cache if it's still invalid. */ if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0) { i915_gem_clflush_object(obj); 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. */ BUG_ON((obj->base.write_domain & ~I915_GEM_DOMAIN_CPU) != 0); /* If we're writing through the CPU, then the GPU read domains will * need to be invalidated at next use. */ if (write) { obj->base.read_domains = I915_GEM_DOMAIN_CPU; obj->base.write_domain = I915_GEM_DOMAIN_CPU; } trace_i915_gem_object_change_domain(obj, old_read_domains, old_write_domain); 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 = dev->dev_private; struct drm_i915_file_private *file_priv = file->driver_priv; unsigned long recent_enough = jiffies - msecs_to_jiffies(20); struct drm_i915_gem_request *request; struct intel_ring_buffer *ring = NULL; unsigned reset_counter; u32 seqno = 0; int ret; ret = i915_gem_wait_for_error(&dev_priv->gpu_error); if (ret) return ret; ret = i915_gem_check_wedge(&dev_priv->gpu_error, false); if (ret) return ret; spin_lock(&file_priv->mm.lock); list_for_each_entry(request, &file_priv->mm.request_list, client_list) { if (time_after_eq(request->emitted_jiffies, recent_enough)) break; ring = request->ring; seqno = request->seqno; } reset_counter = atomic_read(&dev_priv->gpu_error.reset_counter); spin_unlock(&file_priv->mm.lock); if (seqno == 0) return 0; ret = __wait_seqno(ring, seqno, reset_counter, true, NULL); if (ret == 0) queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, 0); return ret; } int i915_gem_object_pin(struct drm_i915_gem_object *obj, uint32_t alignment, bool map_and_fenceable, bool nonblocking) { int ret; if (WARN_ON(obj->pin_count == DRM_I915_GEM_OBJECT_MAX_PIN_COUNT)) return -EBUSY; if (obj->gtt_space != NULL) { if ((alignment && obj->gtt_offset & (alignment - 1)) || (map_and_fenceable && !obj->map_and_fenceable)) { WARN(obj->pin_count, "bo is already pinned with incorrect alignment:" " offset=%x, req.alignment=%x, req.map_and_fenceable=%d," " obj->map_and_fenceable=%d\n", obj->gtt_offset, alignment, map_and_fenceable, obj->map_and_fenceable); ret = i915_gem_object_unbind(obj); if (ret) return ret; } } if (obj->gtt_space == NULL) { struct drm_i915_private *dev_priv = obj->base.dev->dev_private; ret = i915_gem_object_bind_to_gtt(obj, alignment, map_and_fenceable, nonblocking); if (ret) return ret; if (!dev_priv->mm.aliasing_ppgtt) i915_gem_gtt_bind_object(obj, obj->cache_level); } if (!obj->has_global_gtt_mapping && map_and_fenceable) i915_gem_gtt_bind_object(obj, obj->cache_level); obj->pin_count++; obj->pin_mappable |= map_and_fenceable; return 0; } void i915_gem_object_unpin(struct drm_i915_gem_object *obj) { BUG_ON(obj->pin_count == 0); BUG_ON(obj->gtt_space == NULL); if (--obj->pin_count == 0) obj->pin_mappable = false; } int i915_gem_pin_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_pin *args = data; struct drm_i915_gem_object *obj; int ret; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } if (obj->madv != I915_MADV_WILLNEED) { DRM_ERROR("Attempting to pin a purgeable buffer\n"); ret = -EINVAL; goto out; } if (obj->pin_filp != NULL && obj->pin_filp != file) { DRM_ERROR("Already pinned in i915_gem_pin_ioctl(): %d\n", args->handle); ret = -EINVAL; goto out; } if (obj->user_pin_count == 0) { ret = i915_gem_object_pin(obj, args->alignment, true, false); if (ret) goto out; } obj->user_pin_count++; obj->pin_filp = file; /* XXX - flush the CPU caches for pinned objects * as the X server doesn't manage domains yet */ i915_gem_object_flush_cpu_write_domain(obj); args->offset = obj->gtt_offset; out: drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } int i915_gem_unpin_ioctl(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_pin *args = data; struct drm_i915_gem_object *obj; int ret; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } if (obj->pin_filp != file) { DRM_ERROR("Not pinned by caller in i915_gem_pin_ioctl(): %d\n", args->handle); ret = -EINVAL; goto out; } obj->user_pin_count--; if (obj->user_pin_count == 0) { obj->pin_filp = NULL; i915_gem_object_unpin(obj); } out: drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } 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; int ret; ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } /* Count all active objects as busy, even if they are currently not used * by the gpu. Users of this interface expect objects to eventually * become non-busy without any further actions, therefore emit any * necessary flushes here. */ ret = i915_gem_object_flush_active(obj); args->busy = obj->active; if (obj->ring) { BUILD_BUG_ON(I915_NUM_RINGS > 16); args->busy |= intel_ring_flag(obj->ring) << 16; } drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } 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_gem_madvise *args = data; struct drm_i915_gem_object *obj; int ret; switch (args->madv) { case I915_MADV_DONTNEED: case I915_MADV_WILLNEED: break; default: return -EINVAL; } ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; obj = to_intel_bo(drm_gem_object_lookup(dev, file_priv, args->handle)); if (&obj->base == NULL) { ret = -ENOENT; goto unlock; } if (obj->pin_count) { ret = -EINVAL; goto out; } if (obj->madv != __I915_MADV_PURGED) obj->madv = args->madv; /* if the object is no longer attached, discard its backing storage */ if (i915_gem_object_is_purgeable(obj) && obj->pages == NULL) i915_gem_object_truncate(obj); args->retained = obj->madv != __I915_MADV_PURGED; out: drm_gem_object_unreference(&obj->base); unlock: mutex_unlock(&dev->struct_mutex); return ret; } void i915_gem_object_init(struct drm_i915_gem_object *obj, const struct drm_i915_gem_object_ops *ops) { INIT_LIST_HEAD(&obj->mm_list); INIT_LIST_HEAD(&obj->global_list); INIT_LIST_HEAD(&obj->ring_list); INIT_LIST_HEAD(&obj->exec_list); obj->ops = ops; obj->fence_reg = I915_FENCE_REG_NONE; obj->madv = I915_MADV_WILLNEED; /* Avoid an unnecessary call to unbind on the first bind. */ obj->map_and_fenceable = true; i915_gem_info_add_obj(obj->base.dev->dev_private, obj->base.size); } static const struct drm_i915_gem_object_ops i915_gem_object_ops = { .get_pages = i915_gem_object_get_pages_gtt, .put_pages = i915_gem_object_put_pages_gtt, }; struct drm_i915_gem_object *i915_gem_alloc_object(struct drm_device *dev, size_t size) { struct drm_i915_gem_object *obj; struct address_space *mapping; gfp_t mask; obj = i915_gem_object_alloc(dev); if (obj == NULL) return NULL; if (drm_gem_object_init(dev, &obj->base, size) != 0) { i915_gem_object_free(obj); return NULL; } mask = GFP_HIGHUSER | __GFP_RECLAIMABLE; if (IS_CRESTLINE(dev) || IS_BROADWATER(dev)) { /* 965gm cannot relocate objects above 4GiB. */ mask &= ~__GFP_HIGHMEM; mask |= __GFP_DMA32; } mapping = file_inode(obj->base.filp)->i_mapping; mapping_set_gfp_mask(mapping, mask); 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)) { /* 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. */ obj->cache_level = I915_CACHE_LLC; } else obj->cache_level = I915_CACHE_NONE; return obj; } int i915_gem_init_object(struct drm_gem_object *obj) { BUG(); return 0; } void i915_gem_free_object(struct drm_gem_object *gem_obj) { struct drm_i915_gem_object *obj = to_intel_bo(gem_obj); struct drm_device *dev = obj->base.dev; drm_i915_private_t *dev_priv = dev->dev_private; trace_i915_gem_object_destroy(obj); if (obj->phys_obj) i915_gem_detach_phys_object(dev, obj); obj->pin_count = 0; if (WARN_ON(i915_gem_object_unbind(obj) == -ERESTARTSYS)) { bool was_interruptible; was_interruptible = dev_priv->mm.interruptible; dev_priv->mm.interruptible = false; WARN_ON(i915_gem_object_unbind(obj)); dev_priv->mm.interruptible = was_interruptible; } /* Stolen objects don't hold a ref, but do hold pin count. Fix that up * before progressing. */ if (obj->stolen) i915_gem_object_unpin_pages(obj); if (WARN_ON(obj->pages_pin_count)) obj->pages_pin_count = 0; i915_gem_object_put_pages(obj); i915_gem_object_free_mmap_offset(obj); i915_gem_object_release_stolen(obj); BUG_ON(obj->pages); if (obj->base.import_attach) drm_prime_gem_destroy(&obj->base, NULL); drm_gem_object_release(&obj->base); i915_gem_info_remove_obj(dev_priv, obj->base.size); kfree(obj->bit_17); i915_gem_object_free(obj); } int i915_gem_idle(struct drm_device *dev) { drm_i915_private_t *dev_priv = dev->dev_private; int ret; mutex_lock(&dev->struct_mutex); if (dev_priv->mm.suspended) { mutex_unlock(&dev->struct_mutex); return 0; } ret = i915_gpu_idle(dev); if (ret) { mutex_unlock(&dev->struct_mutex); return ret; } i915_gem_retire_requests(dev); /* Under UMS, be paranoid and evict. */ if (!drm_core_check_feature(dev, DRIVER_MODESET)) i915_gem_evict_everything(dev); i915_gem_reset_fences(dev); /* Hack! Don't let anybody do execbuf while we don't control the chip. * We need to replace this with a semaphore, or something. * And not confound mm.suspended! */ dev_priv->mm.suspended = 1; del_timer_sync(&dev_priv->gpu_error.hangcheck_timer); i915_kernel_lost_context(dev); i915_gem_cleanup_ringbuffer(dev); mutex_unlock(&dev->struct_mutex); /* Cancel the retire work handler, which should be idle now. */ cancel_delayed_work_sync(&dev_priv->mm.retire_work); return 0; } void i915_gem_l3_remap(struct drm_device *dev) { drm_i915_private_t *dev_priv = dev->dev_private; u32 misccpctl; int i; if (!HAS_L3_GPU_CACHE(dev)) return; if (!dev_priv->l3_parity.remap_info) return; misccpctl = I915_READ(GEN7_MISCCPCTL); I915_WRITE(GEN7_MISCCPCTL, misccpctl & ~GEN7_DOP_CLOCK_GATE_ENABLE); POSTING_READ(GEN7_MISCCPCTL); for (i = 0; i < GEN7_L3LOG_SIZE; i += 4) { u32 remap = I915_READ(GEN7_L3LOG_BASE + i); if (remap && remap != dev_priv->l3_parity.remap_info[i/4]) DRM_DEBUG("0x%x was already programmed to %x\n", GEN7_L3LOG_BASE + i, remap); if (remap && !dev_priv->l3_parity.remap_info[i/4]) DRM_DEBUG_DRIVER("Clearing remapped register\n"); I915_WRITE(GEN7_L3LOG_BASE + i, dev_priv->l3_parity.remap_info[i/4]); } /* Make sure all the writes land before disabling dop clock gating */ POSTING_READ(GEN7_L3LOG_BASE); I915_WRITE(GEN7_MISCCPCTL, misccpctl); } void i915_gem_init_swizzling(struct drm_device *dev) { drm_i915_private_t *dev_priv = dev->dev_private; if (INTEL_INFO(dev)->gen < 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)) return; I915_WRITE(TILECTL, I915_READ(TILECTL) | TILECTL_SWZCTL); if (IS_GEN6(dev)) I915_WRITE(ARB_MODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_SNB)); else if (IS_GEN7(dev)) I915_WRITE(ARB_MODE, _MASKED_BIT_ENABLE(ARB_MODE_SWIZZLE_IVB)); else BUG(); } static bool intel_enable_blt(struct drm_device *dev) { if (!HAS_BLT(dev)) return false; /* The blitter was dysfunctional on early prototypes */ if (IS_GEN6(dev) && dev->pdev->revision < 8) { DRM_INFO("BLT not supported on this pre-production hardware;" " graphics performance will be degraded.\n"); return false; } return true; } static int i915_gem_init_rings(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; int ret; ret = intel_init_render_ring_buffer(dev); if (ret) return ret; if (HAS_BSD(dev)) { ret = intel_init_bsd_ring_buffer(dev); if (ret) goto cleanup_render_ring; } if (intel_enable_blt(dev)) { ret = intel_init_blt_ring_buffer(dev); if (ret) goto cleanup_bsd_ring; } if (HAS_VEBOX(dev)) { ret = intel_init_vebox_ring_buffer(dev); if (ret) goto cleanup_blt_ring; } ret = i915_gem_set_seqno(dev, ((u32)~0 - 0x1000)); if (ret) goto cleanup_vebox_ring; return 0; cleanup_vebox_ring: intel_cleanup_ring_buffer(&dev_priv->ring[VECS]); cleanup_blt_ring: intel_cleanup_ring_buffer(&dev_priv->ring[BCS]); cleanup_bsd_ring: intel_cleanup_ring_buffer(&dev_priv->ring[VCS]); cleanup_render_ring: intel_cleanup_ring_buffer(&dev_priv->ring[RCS]); return ret; } int i915_gem_init_hw(struct drm_device *dev) { drm_i915_private_t *dev_priv = dev->dev_private; int ret; if (INTEL_INFO(dev)->gen < 6 && !intel_enable_gtt()) return -EIO; if (IS_HASWELL(dev) && (I915_READ(0x120010) == 1)) I915_WRITE(0x9008, I915_READ(0x9008) | 0xf0000); if (HAS_PCH_NOP(dev)) { u32 temp = I915_READ(GEN7_MSG_CTL); temp &= ~(WAIT_FOR_PCH_FLR_ACK | WAIT_FOR_PCH_RESET_ACK); I915_WRITE(GEN7_MSG_CTL, temp); } i915_gem_l3_remap(dev); i915_gem_init_swizzling(dev); ret = i915_gem_init_rings(dev); if (ret) return ret; /* * XXX: There was some w/a described somewhere suggesting loading * contexts before PPGTT. */ i915_gem_context_init(dev); if (dev_priv->mm.aliasing_ppgtt) { ret = dev_priv->mm.aliasing_ppgtt->enable(dev); if (ret) { i915_gem_cleanup_aliasing_ppgtt(dev); DRM_INFO("PPGTT enable failed. This is not fatal, but unexpected\n"); } } return 0; } int i915_gem_init(struct drm_device *dev) { struct drm_i915_private *dev_priv = dev->dev_private; int ret; mutex_lock(&dev->struct_mutex); if (IS_VALLEYVIEW(dev)) { /* VLVA0 (potential hack), BIOS isn't actually waking us */ I915_WRITE(VLV_GTLC_WAKE_CTRL, 1); if (wait_for((I915_READ(VLV_GTLC_PW_STATUS) & 1) == 1, 10)) DRM_DEBUG_DRIVER("allow wake ack timed out\n"); } i915_gem_init_global_gtt(dev); ret = i915_gem_init_hw(dev); mutex_unlock(&dev->struct_mutex); if (ret) { i915_gem_cleanup_aliasing_ppgtt(dev); return ret; } /* Allow hardware batchbuffers unless told otherwise, but not for KMS. */ if (!drm_core_check_feature(dev, DRIVER_MODESET)) dev_priv->dri1.allow_batchbuffer = 1; return 0; } void i915_gem_cleanup_ringbuffer(struct drm_device *dev) { drm_i915_private_t *dev_priv = dev->dev_private; struct intel_ring_buffer *ring; int i; for_each_ring(ring, dev_priv, i) intel_cleanup_ring_buffer(ring); } int i915_gem_entervt_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { drm_i915_private_t *dev_priv = dev->dev_private; int ret; if (drm_core_check_feature(dev, DRIVER_MODESET)) return 0; if (i915_reset_in_progress(&dev_priv->gpu_error)) { DRM_ERROR("Reenabling wedged hardware, good luck\n"); atomic_set(&dev_priv->gpu_error.reset_counter, 0); } mutex_lock(&dev->struct_mutex); dev_priv->mm.suspended = 0; ret = i915_gem_init_hw(dev); if (ret != 0) { mutex_unlock(&dev->struct_mutex); return ret; } BUG_ON(!list_empty(&dev_priv->mm.active_list)); mutex_unlock(&dev->struct_mutex); ret = drm_irq_install(dev); if (ret) goto cleanup_ringbuffer; return 0; cleanup_ringbuffer: mutex_lock(&dev->struct_mutex); i915_gem_cleanup_ringbuffer(dev); dev_priv->mm.suspended = 1; mutex_unlock(&dev->struct_mutex); return ret; } int i915_gem_leavevt_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) { if (drm_core_check_feature(dev, DRIVER_MODESET)) return 0; drm_irq_uninstall(dev); return i915_gem_idle(dev); } void i915_gem_lastclose(struct drm_device *dev) { int ret; if (drm_core_check_feature(dev, DRIVER_MODESET)) return; ret = i915_gem_idle(dev); if (ret) DRM_ERROR("failed to idle hardware: %d\n", ret); } static void init_ring_lists(struct intel_ring_buffer *ring) { INIT_LIST_HEAD(&ring->active_list); INIT_LIST_HEAD(&ring->request_list); } void i915_gem_load(struct drm_device *dev) { drm_i915_private_t *dev_priv = dev->dev_private; int i; dev_priv->slab = kmem_cache_create("i915_gem_object", sizeof(struct drm_i915_gem_object), 0, SLAB_HWCACHE_ALIGN, NULL); INIT_LIST_HEAD(&dev_priv->mm.active_list); INIT_LIST_HEAD(&dev_priv->mm.inactive_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); for (i = 0; i < I915_NUM_RINGS; i++) init_ring_lists(&dev_priv->ring[i]); for (i = 0; i < I915_MAX_NUM_FENCES; i++) INIT_LIST_HEAD(&dev_priv->fence_regs[i].lru_list); INIT_DELAYED_WORK(&dev_priv->mm.retire_work, i915_gem_retire_work_handler); init_waitqueue_head(&dev_priv->gpu_error.reset_queue); /* On GEN3 we really need to make sure the ARB C3 LP bit is set */ if (IS_GEN3(dev)) { I915_WRITE(MI_ARB_STATE, _MASKED_BIT_ENABLE(MI_ARB_C3_LP_WRITE_ENABLE)); } dev_priv->relative_constants_mode = I915_EXEC_CONSTANTS_REL_GENERAL; /* Old X drivers will take 0-2 for front, back, depth buffers */ if (!drm_core_check_feature(dev, DRIVER_MODESET)) dev_priv->fence_reg_start = 3; if (INTEL_INFO(dev)->gen >= 7 && !IS_VALLEYVIEW(dev)) dev_priv->num_fence_regs = 32; else if (INTEL_INFO(dev)->gen >= 4 || IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev)) dev_priv->num_fence_regs = 16; else dev_priv->num_fence_regs = 8; /* Initialize fence registers to zero */ i915_gem_reset_fences(dev); i915_gem_detect_bit_6_swizzle(dev); init_waitqueue_head(&dev_priv->pending_flip_queue); dev_priv->mm.interruptible = true; dev_priv->mm.inactive_shrinker.shrink = i915_gem_inactive_shrink; dev_priv->mm.inactive_shrinker.seeks = DEFAULT_SEEKS; register_shrinker(&dev_priv->mm.inactive_shrinker); } /* * Create a physically contiguous memory object for this object * e.g. for cursor + overlay regs */ static int i915_gem_init_phys_object(struct drm_device *dev, int id, int size, int align) { drm_i915_private_t *dev_priv = dev->dev_private; struct drm_i915_gem_phys_object *phys_obj; int ret; if (dev_priv->mm.phys_objs[id - 1] || !size) return 0; phys_obj = kzalloc(sizeof(struct drm_i915_gem_phys_object), GFP_KERNEL); if (!phys_obj) return -ENOMEM; phys_obj->id = id; phys_obj->handle = drm_pci_alloc(dev, size, align); if (!phys_obj->handle) { ret = -ENOMEM; goto kfree_obj; } #ifdef CONFIG_X86 set_memory_wc((unsigned long)phys_obj->handle->vaddr, phys_obj->handle->size / PAGE_SIZE); #endif dev_priv->mm.phys_objs[id - 1] = phys_obj; return 0; kfree_obj: kfree(phys_obj); return ret; } static void i915_gem_free_phys_object(struct drm_device *dev, int id) { drm_i915_private_t *dev_priv = dev->dev_private; struct drm_i915_gem_phys_object *phys_obj; if (!dev_priv->mm.phys_objs[id - 1]) return; phys_obj = dev_priv->mm.phys_objs[id - 1]; if (phys_obj->cur_obj) { i915_gem_detach_phys_object(dev, phys_obj->cur_obj); } #ifdef CONFIG_X86 set_memory_wb((unsigned long)phys_obj->handle->vaddr, phys_obj->handle->size / PAGE_SIZE); #endif drm_pci_free(dev, phys_obj->handle); kfree(phys_obj); dev_priv->mm.phys_objs[id - 1] = NULL; } void i915_gem_free_all_phys_object(struct drm_device *dev) { int i; for (i = I915_GEM_PHYS_CURSOR_0; i <= I915_MAX_PHYS_OBJECT; i++) i915_gem_free_phys_object(dev, i); } void i915_gem_detach_phys_object(struct drm_device *dev, struct drm_i915_gem_object *obj) { struct address_space *mapping = file_inode(obj->base.filp)->i_mapping; char *vaddr; int i; int page_count; if (!obj->phys_obj) return; vaddr = obj->phys_obj->handle->vaddr; page_count = obj->base.size / PAGE_SIZE; for (i = 0; i < page_count; i++) { struct page *page = shmem_read_mapping_page(mapping, i); if (!IS_ERR(page)) { char *dst = kmap_atomic(page); memcpy(dst, vaddr + i*PAGE_SIZE, PAGE_SIZE); kunmap_atomic(dst); drm_clflush_pages(&page, 1); set_page_dirty(page); mark_page_accessed(page); page_cache_release(page); } } i915_gem_chipset_flush(dev); obj->phys_obj->cur_obj = NULL; obj->phys_obj = NULL; } int i915_gem_attach_phys_object(struct drm_device *dev, struct drm_i915_gem_object *obj, int id, int align) { struct address_space *mapping = file_inode(obj->base.filp)->i_mapping; drm_i915_private_t *dev_priv = dev->dev_private; int ret = 0; int page_count; int i; if (id > I915_MAX_PHYS_OBJECT) return -EINVAL; if (obj->phys_obj) { if (obj->phys_obj->id == id) return 0; i915_gem_detach_phys_object(dev, obj); } /* create a new object */ if (!dev_priv->mm.phys_objs[id - 1]) { ret = i915_gem_init_phys_object(dev, id, obj->base.size, align); if (ret) { DRM_ERROR("failed to init phys object %d size: %zu\n", id, obj->base.size); return ret; } } /* bind to the object */ obj->phys_obj = dev_priv->mm.phys_objs[id - 1]; obj->phys_obj->cur_obj = obj; page_count = obj->base.size / PAGE_SIZE; for (i = 0; i < page_count; i++) { struct page *page; char *dst, *src; page = shmem_read_mapping_page(mapping, i); if (IS_ERR(page)) return PTR_ERR(page); src = kmap_atomic(page); dst = obj->phys_obj->handle->vaddr + (i * PAGE_SIZE); memcpy(dst, src, PAGE_SIZE); kunmap_atomic(src); mark_page_accessed(page); page_cache_release(page); } return 0; } static int i915_gem_phys_pwrite(struct drm_device *dev, struct drm_i915_gem_object *obj, struct drm_i915_gem_pwrite *args, struct drm_file *file_priv) { void *vaddr = obj->phys_obj->handle->vaddr + args->offset; char __user *user_data = to_user_ptr(args->data_ptr); if (__copy_from_user_inatomic_nocache(vaddr, user_data, args->size)) { unsigned long unwritten; /* The physical object once assigned is fixed for the lifetime * of the obj, so we can safely drop the lock and continue * to access vaddr. */ mutex_unlock(&dev->struct_mutex); unwritten = copy_from_user(vaddr, user_data, args->size); mutex_lock(&dev->struct_mutex); if (unwritten) return -EFAULT; } i915_gem_chipset_flush(dev); return 0; } void i915_gem_release(struct drm_device *dev, struct drm_file *file) { struct drm_i915_file_private *file_priv = file->driver_priv; /* 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); while (!list_empty(&file_priv->mm.request_list)) { struct drm_i915_gem_request *request; request = list_first_entry(&file_priv->mm.request_list, struct drm_i915_gem_request, client_list); list_del(&request->client_list); request->file_priv = NULL; } spin_unlock(&file_priv->mm.lock); } static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task) { if (!mutex_is_locked(mutex)) return false; #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES) return mutex->owner == task; #else /* Since UP may be pre-empted, we cannot assume that we own the lock */ return false; #endif } static int i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc) { struct drm_i915_private *dev_priv = container_of(shrinker, struct drm_i915_private, mm.inactive_shrinker); struct drm_device *dev = dev_priv->dev; struct drm_i915_gem_object *obj; int nr_to_scan = sc->nr_to_scan; bool unlock = true; int cnt; if (!mutex_trylock(&dev->struct_mutex)) { if (!mutex_is_locked_by(&dev->struct_mutex, current)) return 0; if (dev_priv->mm.shrinker_no_lock_stealing) return 0; unlock = false; } if (nr_to_scan) { nr_to_scan -= i915_gem_purge(dev_priv, nr_to_scan); if (nr_to_scan > 0) nr_to_scan -= __i915_gem_shrink(dev_priv, nr_to_scan, false); if (nr_to_scan > 0) i915_gem_shrink_all(dev_priv); } cnt = 0; list_for_each_entry(obj, &dev_priv->mm.unbound_list, global_list) if (obj->pages_pin_count == 0) cnt += obj->base.size >> PAGE_SHIFT; list_for_each_entry(obj, &dev_priv->mm.inactive_list, global_list) if (obj->pin_count == 0 && obj->pages_pin_count == 0) cnt += obj->base.size >> PAGE_SHIFT; if (unlock) mutex_unlock(&dev->struct_mutex); return cnt; }