diff options
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem.c | 166 |
1 files changed, 139 insertions, 27 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 37427e4016c..35f8c7bd0d3 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -223,29 +223,34 @@ fast_user_write(struct io_mapping *mapping, */ static inline int -slow_user_write(struct io_mapping *mapping, - loff_t page_base, int page_offset, - char __user *user_data, - int length) +slow_kernel_write(struct io_mapping *mapping, + loff_t gtt_base, int gtt_offset, + struct page *user_page, int user_offset, + int length) { - char __iomem *vaddr; + char *src_vaddr, *dst_vaddr; unsigned long unwritten; - vaddr = io_mapping_map_wc(mapping, page_base); - if (vaddr == NULL) - return -EFAULT; - unwritten = __copy_from_user(vaddr + page_offset, - user_data, length); - io_mapping_unmap(vaddr); + dst_vaddr = io_mapping_map_atomic_wc(mapping, gtt_base); + src_vaddr = kmap_atomic(user_page, KM_USER1); + unwritten = __copy_from_user_inatomic_nocache(dst_vaddr + gtt_offset, + src_vaddr + user_offset, + length); + kunmap_atomic(src_vaddr, KM_USER1); + io_mapping_unmap_atomic(dst_vaddr); if (unwritten) return -EFAULT; return 0; } +/** + * 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(struct drm_device *dev, struct drm_gem_object *obj, - struct drm_i915_gem_pwrite *args, - struct drm_file *file_priv) +i915_gem_gtt_pwrite_fast(struct drm_device *dev, struct drm_gem_object *obj, + struct drm_i915_gem_pwrite *args, + struct drm_file *file_priv) { struct drm_i915_gem_object *obj_priv = obj->driver_private; drm_i915_private_t *dev_priv = dev->dev_private; @@ -273,7 +278,6 @@ i915_gem_gtt_pwrite(struct drm_device *dev, struct drm_gem_object *obj, obj_priv = obj->driver_private; offset = obj_priv->gtt_offset + args->offset; - obj_priv->dirty = 1; while (remain > 0) { /* Operation in this page @@ -292,16 +296,11 @@ i915_gem_gtt_pwrite(struct drm_device *dev, struct drm_gem_object *obj, page_offset, user_data, page_length); /* If we get a fault while copying data, then (presumably) our - * source page isn't available. In this case, use the - * non-atomic function + * source page isn't available. Return the error and we'll + * retry in the slow path. */ - if (ret) { - ret = slow_user_write (dev_priv->mm.gtt_mapping, - page_base, page_offset, - user_data, page_length); - if (ret) - goto fail; - } + if (ret) + goto fail; remain -= page_length; user_data += page_length; @@ -315,6 +314,115 @@ fail: return ret; } +/** + * This is the fallback GTT pwrite path, which uses get_user_pages to pin + * the memory and maps it using kmap_atomic for copying. + * + * This code resulted in x11perf -rgb10text consuming about 10% more CPU + * than using i915_gem_gtt_pwrite_fast on a G45 (32-bit). + */ +static int +i915_gem_gtt_pwrite_slow(struct drm_device *dev, struct drm_gem_object *obj, + struct drm_i915_gem_pwrite *args, + struct drm_file *file_priv) +{ + struct drm_i915_gem_object *obj_priv = obj->driver_private; + drm_i915_private_t *dev_priv = dev->dev_private; + ssize_t remain; + loff_t gtt_page_base, offset; + loff_t first_data_page, last_data_page, num_pages; + loff_t pinned_pages, i; + struct page **user_pages; + struct mm_struct *mm = current->mm; + int gtt_page_offset, data_page_offset, data_page_index, page_length; + int ret; + uint64_t data_ptr = args->data_ptr; + + remain = args->size; + + /* Pin the user pages containing the data. We can't fault while + * holding the struct mutex, and all of the pwrite implementations + * want to hold it while dereferencing the user data. + */ + first_data_page = data_ptr / PAGE_SIZE; + last_data_page = (data_ptr + args->size - 1) / PAGE_SIZE; + num_pages = last_data_page - first_data_page + 1; + + user_pages = kcalloc(num_pages, sizeof(struct page *), GFP_KERNEL); + if (user_pages == NULL) + return -ENOMEM; + + down_read(&mm->mmap_sem); + pinned_pages = get_user_pages(current, mm, (uintptr_t)args->data_ptr, + num_pages, 0, 0, user_pages, NULL); + up_read(&mm->mmap_sem); + if (pinned_pages < num_pages) { + ret = -EFAULT; + goto out_unpin_pages; + } + + mutex_lock(&dev->struct_mutex); + ret = i915_gem_object_pin(obj, 0); + if (ret) + goto out_unlock; + + ret = i915_gem_object_set_to_gtt_domain(obj, 1); + if (ret) + goto out_unpin_object; + + obj_priv = obj->driver_private; + offset = obj_priv->gtt_offset + args->offset; + + while (remain > 0) { + /* Operation in this page + * + * gtt_page_base = page offset within aperture + * gtt_page_offset = offset within page in aperture + * data_page_index = page number in get_user_pages return + * data_page_offset = offset with data_page_index page. + * page_length = bytes to copy for this page + */ + gtt_page_base = offset & PAGE_MASK; + gtt_page_offset = offset & ~PAGE_MASK; + data_page_index = data_ptr / PAGE_SIZE - first_data_page; + data_page_offset = data_ptr & ~PAGE_MASK; + + page_length = remain; + if ((gtt_page_offset + page_length) > PAGE_SIZE) + page_length = PAGE_SIZE - gtt_page_offset; + if ((data_page_offset + page_length) > PAGE_SIZE) + page_length = PAGE_SIZE - data_page_offset; + + ret = slow_kernel_write(dev_priv->mm.gtt_mapping, + gtt_page_base, gtt_page_offset, + user_pages[data_page_index], + data_page_offset, + page_length); + + /* 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 (ret) + goto out_unpin_object; + + remain -= page_length; + offset += page_length; + data_ptr += page_length; + } + +out_unpin_object: + i915_gem_object_unpin(obj); +out_unlock: + mutex_unlock(&dev->struct_mutex); +out_unpin_pages: + for (i = 0; i < pinned_pages; i++) + page_cache_release(user_pages[i]); + kfree(user_pages); + + return ret; +} + static int i915_gem_shmem_pwrite(struct drm_device *dev, struct drm_gem_object *obj, struct drm_i915_gem_pwrite *args, @@ -388,9 +496,13 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data, if (obj_priv->phys_obj) ret = i915_gem_phys_pwrite(dev, obj, args, file_priv); else if (obj_priv->tiling_mode == I915_TILING_NONE && - dev->gtt_total != 0) - ret = i915_gem_gtt_pwrite(dev, obj, args, file_priv); - else + dev->gtt_total != 0) { + ret = i915_gem_gtt_pwrite_fast(dev, obj, args, file_priv); + if (ret == -EFAULT) { + ret = i915_gem_gtt_pwrite_slow(dev, obj, args, + file_priv); + } + } else ret = i915_gem_shmem_pwrite(dev, obj, args, file_priv); #if WATCH_PWRITE |