drm/i915: add GEM GTT mapping support

Use the new core GEM object mapping code to allow GTT mapping of GEM
objects on i915. The fault handler will make sure a fence register is
allocated too, if the object in question is tiled.

Signed-off-by: Jesse Barnes <[e-mail]>
Signed-off-by: Eric Anholt <[e-mail]>
Signed-off-by: Dave Airlie <[e-mail]>

drivers/gpu/drm/i915/i915_dma.c

···
 	DRM_IOCTL_DEF(DRM_I915_GEM_PREAD, i915_gem_pread_ioctl, 0),
 	DRM_IOCTL_DEF(DRM_I915_GEM_PWRITE, i915_gem_pwrite_ioctl, 0),
 	DRM_IOCTL_DEF(DRM_I915_GEM_MMAP, i915_gem_mmap_ioctl, 0),
+	DRM_IOCTL_DEF(DRM_I915_GEM_MMAP_GTT, i915_gem_mmap_gtt_ioctl, 0),
 	DRM_IOCTL_DEF(DRM_I915_GEM_SET_DOMAIN, i915_gem_set_domain_ioctl, 0),
 	DRM_IOCTL_DEF(DRM_I915_GEM_SW_FINISH, i915_gem_sw_finish_ioctl, 0),
 	DRM_IOCTL_DEF(DRM_I915_GEM_SET_TILING, i915_gem_set_tiling, 0),

drivers/gpu/drm/i915/i915_drv.c

···
 	return 0;
 }
 
+static struct vm_operations_struct i915_gem_vm_ops = {
+	.fault = i915_gem_fault,
+};
+
 static struct drm_driver driver = {
 	/* don't use mtrr's here, the Xserver or user space app should
 	 * deal with them for intel hardware.
···
 	.proc_cleanup = i915_gem_proc_cleanup,
 	.gem_init_object = i915_gem_init_object,
 	.gem_free_object = i915_gem_free_object,
+	.gem_vm_ops = &i915_gem_vm_ops,
 	.ioctls = i915_ioctls,
 	.fops = {
 		 .owner = THIS_MODULE,
 		 .open = drm_open,
 		 .release = drm_release,
 		 .ioctl = drm_ioctl,
-		 .mmap = drm_mmap,
+		 .mmap = drm_gem_mmap,
 		 .poll = drm_poll,
 		 .fasync = drm_fasync,
 #ifdef CONFIG_COMPAT

drivers/gpu/drm/i915/i915_drv.h

···
 	drm_local_map_t *sarea;
 	struct _drm_i915_sarea *sarea_priv;
 };
+#define I915_FENCE_REG_NONE -1
+
+struct drm_i915_fence_reg {
+	struct drm_gem_object *obj;
+};
 
 typedef struct drm_i915_private {
 	struct drm_device *dev;
···
 	int vblank_pipe;
 
 	struct intel_opregion opregion;
+
+	struct drm_i915_fence_reg fence_regs[16]; /* assume 965 */
+	int fence_reg_start; /* 4 if userland hasn't ioctl'd us yet */
+	int num_fence_regs; /* 8 on pre-965, 16 otherwise */
 
 	/* Register state */
 	u8 saveLBB;
···
 	 * This is the same as gtt_space->start
 	 */
 	uint32_t gtt_offset;
+	/**
+	 * Required alignment for the object
+	 */
+	uint32_t gtt_alignment;
+	/**
+	 * Fake offset for use by mmap(2)
+	 */
+	uint64_t mmap_offset;
+
+	/**
+	 * Fence register bits (if any) for this object.  Will be set
+	 * as needed when mapped into the GTT.
+	 * Protected by dev->struct_mutex.
+	 */
+	int fence_reg;
 
 	/** Boolean whether this object has a valid gtt offset. */
 	int gtt_bound;
···
 
 	/** Current tiling mode for the object. */
 	uint32_t tiling_mode;
+	uint32_t stride;
 
 	/** AGP mapping type (AGP_USER_MEMORY or AGP_USER_CACHED_MEMORY */
 	uint32_t agp_type;
···
 			  struct drm_file *file_priv);
 int i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 			struct drm_file *file_priv);
+int i915_gem_mmap_gtt_ioctl(struct drm_device *dev, void *data,
+			struct drm_file *file_priv);
 int i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
 			      struct drm_file *file_priv);
 int i915_gem_sw_finish_ioctl(struct drm_device *dev, void *data,
···
 void i915_gem_retire_requests(struct drm_device *dev);
 void i915_gem_retire_work_handler(struct work_struct *work);
 void i915_gem_clflush_object(struct drm_gem_object *obj);
+int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf);
 
 /* i915_gem_tiling.c */
 void i915_gem_detect_bit_6_swizzle(struct drm_device *dev);
···
 #define I915_WRITE16(reg, val)	writel(val, dev_priv->regs + (reg))
 #define I915_READ8(reg)		readb(dev_priv->regs + (reg))
 #define I915_WRITE8(reg, val)	writeb(val, dev_priv->regs + (reg))
+#ifdef writeq
+#define I915_WRITE64(reg, val)	writeq(val, dev_priv->regs + (reg))
+#else
+#define I915_WRITE64(reg, val)	(writel(val, dev_priv->regs + (reg)), \
+				 writel(upper_32_bits(val), dev_priv->regs + \
+					(reg) + 4))
+#endif
 
 #define I915_VERBOSE 0
 

drivers/gpu/drm/i915/i915_gem.c

···
 static int i915_gem_object_get_page_list(struct drm_gem_object *obj);
 static void i915_gem_object_free_page_list(struct drm_gem_object *obj);
 static int i915_gem_object_wait_rendering(struct drm_gem_object *obj);
+static int i915_gem_object_bind_to_gtt(struct drm_gem_object *obj,
+					   unsigned alignment);
+static void i915_gem_object_get_fence_reg(struct drm_gem_object *obj);
+static void i915_gem_clear_fence_reg(struct drm_gem_object *obj);
+static int i915_gem_evict_something(struct drm_device *dev);
 
 static void
 i915_gem_cleanup_ringbuffer(struct drm_device *dev);
···
 	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_gem_object *obj = vma->vm_private_data;
+	struct drm_device *dev = obj->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	pgoff_t page_offset;
+	unsigned long pfn;
+	int ret = 0;
+
+	/* We don't use vmf->pgoff since that has the fake offset */
+	page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
+		PAGE_SHIFT;
+
+	/* Now bind it into the GTT if needed */
+	mutex_lock(&dev->struct_mutex);
+	if (!obj_priv->gtt_space) {
+		ret = i915_gem_object_bind_to_gtt(obj, obj_priv->gtt_alignment);
+		if (ret) {
+			mutex_unlock(&dev->struct_mutex);
+			return VM_FAULT_SIGBUS;
+		}
+		list_add(&obj_priv->list, &dev_priv->mm.inactive_list);
+	}
+
+	/* Need a new fence register? */
+	if (obj_priv->fence_reg == I915_FENCE_REG_NONE &&
+	    obj_priv->tiling_mode != I915_TILING_NONE)
+		i915_gem_object_get_fence_reg(obj);
+
+	pfn = ((dev->agp->base + obj_priv->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);
+
+	mutex_unlock(&dev->struct_mutex);
+
+	switch (ret) {
+	case -ENOMEM:
+	case -EAGAIN:
+		return VM_FAULT_OOM;
+	case -EFAULT:
+	case -EBUSY:
+		DRM_ERROR("can't insert pfn??  fault or busy...\n");
+		return VM_FAULT_SIGBUS;
+	default:
+		return VM_FAULT_NOPAGE;
+	}
+}
+
+/**
+ * i915_gem_create_mmap_offset - create a fake mmap offset for an object
+ * @obj: obj in question
+ *
+ * GEM memory mapping works by handing back to userspace a fake mmap offset
+ * it can use in a subsequent mmap(2) call.  The DRM core code then looks
+ * up the object based on the offset and sets up the various memory mapping
+ * structures.
+ *
+ * This routine allocates and attaches a fake offset for @obj.
+ */
+static int
+i915_gem_create_mmap_offset(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	struct drm_gem_mm *mm = dev->mm_private;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	struct drm_map_list *list;
+	struct drm_map *map;
+	int ret = 0;
+
+	/* Set the object up for mmap'ing */
+	list = &obj->map_list;
+	list->map = drm_calloc(1, sizeof(struct drm_map_list),
+			       DRM_MEM_DRIVER);
+	if (!list->map)
+		return -ENOMEM;
+
+	map = list->map;
+	map->type = _DRM_GEM;
+	map->size = obj->size;
+	map->handle = obj;
+
+	/* Get a DRM GEM mmap offset allocated... */
+	list->file_offset_node = drm_mm_search_free(&mm->offset_manager,
+						    obj->size / PAGE_SIZE, 0, 0);
+	if (!list->file_offset_node) {
+		DRM_ERROR("failed to allocate offset for bo %d\n", obj->name);
+		ret = -ENOMEM;
+		goto out_free_list;
+	}
+
+	list->file_offset_node = drm_mm_get_block(list->file_offset_node,
+						  obj->size / PAGE_SIZE, 0);
+	if (!list->file_offset_node) {
+		ret = -ENOMEM;
+		goto out_free_list;
+	}
+
+	list->hash.key = list->file_offset_node->start;
+	if (drm_ht_insert_item(&mm->offset_hash, &list->hash)) {
+		DRM_ERROR("failed to add to map hash\n");
+		goto out_free_mm;
+	}
+
+	/* By now we should be all set, any drm_mmap request on the offset
+	 * below will get to our mmap & fault handler */
+	obj_priv->mmap_offset = ((uint64_t) list->hash.key) << PAGE_SHIFT;
+
+	return 0;
+
+out_free_mm:
+	drm_mm_put_block(list->file_offset_node);
+out_free_list:
+	drm_free(list->map, sizeof(struct drm_map_list), DRM_MEM_DRIVER);
+
+	return ret;
+}
+
+/**
+ * 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 if needed.
+ */
+static uint32_t
+i915_gem_get_gtt_alignment(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	int start, i;
+
+	/*
+	 * Minimum alignment is 4k (GTT page size), but might be greater
+	 * if a fence register is needed for the object.
+	 */
+	if (IS_I965G(dev) || obj_priv->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.
+	 */
+	if (IS_I9XX(dev))
+		start = 1024*1024;
+	else
+		start = 512*1024;
+
+	for (i = start; i < obj->size; i <<= 1)
+		;
+
+	return i;
+}
+
+/**
+ * i915_gem_mmap_gtt_ioctl - prepare an object for GTT mmap'ing
+ * @dev: DRM device
+ * @data: GTT mapping ioctl data
+ * @file_priv: 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_priv)
+{
+	struct drm_i915_gem_mmap_gtt *args = data;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_gem_object *obj;
+	struct drm_i915_gem_object *obj_priv;
+	int ret;
+
+	if (!(dev->driver->driver_features & DRIVER_GEM))
+		return -ENODEV;
+
+	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
+	if (obj == NULL)
+		return -EBADF;
+
+	mutex_lock(&dev->struct_mutex);
+
+	obj_priv = obj->driver_private;
+
+	if (!obj_priv->mmap_offset) {
+		ret = i915_gem_create_mmap_offset(obj);
+		if (ret)
+			return ret;
+	}
+
+	args->offset = obj_priv->mmap_offset;
+
+	obj_priv->gtt_alignment = i915_gem_get_gtt_alignment(obj);
+
+	/* Make sure the alignment is correct for fence regs etc */
+	if (obj_priv->agp_mem &&
+	    (obj_priv->gtt_offset & (obj_priv->gtt_alignment - 1))) {
+		drm_gem_object_unreference(obj);
+		mutex_unlock(&dev->struct_mutex);
+		return -EINVAL;
+	}
+
+	/*
+	 * Pull it into the GTT so that we have a page list (makes the
+	 * initial fault faster and any subsequent flushing possible).
+	 */
+	if (!obj_priv->agp_mem) {
+		ret = i915_gem_object_bind_to_gtt(obj, obj_priv->gtt_alignment);
+		if (ret) {
+			drm_gem_object_unreference(obj);
+			mutex_unlock(&dev->struct_mutex);
+			return ret;
+		}
+		list_add(&obj_priv->list, &dev_priv->mm.inactive_list);
+	}
+
+	drm_gem_object_unreference(obj);
+	mutex_unlock(&dev->struct_mutex);
+
+	return 0;
+}
+
 static void
 i915_gem_object_free_page_list(struct drm_gem_object *obj)
 {
···
 		 */
 		if (obj_priv->last_rendering_seqno != request->seqno)
 			return;
+
 #if WATCH_LRU
 		DRM_INFO("%s: retire %d moves to inactive list %p\n",
 			 __func__, request->seqno, obj);
···
 {
 	struct drm_device *dev = obj->dev;
 	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	loff_t offset;
 	int ret = 0;
 
 #if WATCH_BUF
···
 	}
 
 	BUG_ON(obj_priv->active);
+
+	/* blow away mappings if mapped through GTT */
+	offset = ((loff_t) obj->map_list.hash.key) << PAGE_SHIFT;
+	unmap_mapping_range(dev->dev_mapping, offset, obj->size, 1);
+
+	if (obj_priv->fence_reg != I915_FENCE_REG_NONE)
+		i915_gem_clear_fence_reg(obj);
 
 	i915_gem_object_free_page_list(obj);
 
···
 		obj_priv->page_list[i] = page;
 	}
 	return 0;
+}
+
+static void i965_write_fence_reg(struct drm_i915_fence_reg *reg)
+{
+	struct drm_gem_object *obj = reg->obj;
+	struct drm_device *dev = obj->dev;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	int regnum = obj_priv->fence_reg;
+	uint64_t val;
+
+	val = (uint64_t)((obj_priv->gtt_offset + obj->size - 4096) &
+		    0xfffff000) << 32;
+	val |= obj_priv->gtt_offset & 0xfffff000;
+	val |= ((obj_priv->stride / 128) - 1) << I965_FENCE_PITCH_SHIFT;
+	if (obj_priv->tiling_mode == I915_TILING_Y)
+		val |= 1 << I965_FENCE_TILING_Y_SHIFT;
+	val |= I965_FENCE_REG_VALID;
+
+	I915_WRITE64(FENCE_REG_965_0 + (regnum * 8), val);
+}
+
+static void i915_write_fence_reg(struct drm_i915_fence_reg *reg)
+{
+	struct drm_gem_object *obj = reg->obj;
+	struct drm_device *dev = obj->dev;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	int regnum = obj_priv->fence_reg;
+	uint32_t val;
+	uint32_t pitch_val;
+
+	if ((obj_priv->gtt_offset & ~I915_FENCE_START_MASK) ||
+	    (obj_priv->gtt_offset & (obj->size - 1))) {
+		WARN(1, "%s: object not 1M or size aligned\n", __FUNCTION__);
+		return;
+	}
+
+	if (obj_priv->tiling_mode == I915_TILING_Y && (IS_I945G(dev) ||
+						       IS_I945GM(dev) ||
+						       IS_G33(dev)))
+		pitch_val = (obj_priv->stride / 128) - 1;
+	else
+		pitch_val = (obj_priv->stride / 512) - 1;
+
+	val = obj_priv->gtt_offset;
+	if (obj_priv->tiling_mode == I915_TILING_Y)
+		val |= 1 << I830_FENCE_TILING_Y_SHIFT;
+	val |= I915_FENCE_SIZE_BITS(obj->size);
+	val |= pitch_val << I830_FENCE_PITCH_SHIFT;
+	val |= I830_FENCE_REG_VALID;
+
+	I915_WRITE(FENCE_REG_830_0 + (regnum * 4), val);
+}
+
+static void i830_write_fence_reg(struct drm_i915_fence_reg *reg)
+{
+	struct drm_gem_object *obj = reg->obj;
+	struct drm_device *dev = obj->dev;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	int regnum = obj_priv->fence_reg;
+	uint32_t val;
+	uint32_t pitch_val;
+
+	if ((obj_priv->gtt_offset & ~I915_FENCE_START_MASK) ||
+	    (obj_priv->gtt_offset & (obj->size - 1))) {
+		WARN(1, "%s: object not 1M or size aligned\n", __FUNCTION__);
+		return;
+	}
+
+	pitch_val = (obj_priv->stride / 128) - 1;
+
+	val = obj_priv->gtt_offset;
+	if (obj_priv->tiling_mode == I915_TILING_Y)
+		val |= 1 << I830_FENCE_TILING_Y_SHIFT;
+	val |= I830_FENCE_SIZE_BITS(obj->size);
+	val |= pitch_val << I830_FENCE_PITCH_SHIFT;
+	val |= I830_FENCE_REG_VALID;
+
+	I915_WRITE(FENCE_REG_830_0 + (regnum * 4), val);
+
+}
+
+/**
+ * i915_gem_object_get_fence_reg - set up a fence reg 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.
+ */
+static void
+i915_gem_object_get_fence_reg(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+	struct drm_i915_fence_reg *reg = NULL;
+	int i, ret;
+
+	switch (obj_priv->tiling_mode) {
+	case I915_TILING_NONE:
+		WARN(1, "allocating a fence for non-tiled object?\n");
+		break;
+	case I915_TILING_X:
+		WARN(obj_priv->stride & (512 - 1),
+		     "object is X tiled but has non-512B pitch\n");
+		break;
+	case I915_TILING_Y:
+		WARN(obj_priv->stride & (128 - 1),
+		     "object is Y tiled but has non-128B pitch\n");
+		break;
+	}
+
+	/* First try to find a free reg */
+	for (i = dev_priv->fence_reg_start; i < dev_priv->num_fence_regs; i++) {
+		reg = &dev_priv->fence_regs[i];
+		if (!reg->obj)
+			break;
+	}
+
+	/* None available, try to steal one or wait for a user to finish */
+	if (i == dev_priv->num_fence_regs) {
+		struct drm_i915_gem_object *old_obj_priv = NULL;
+		loff_t offset;
+
+try_again:
+		/* Could try to use LRU here instead... */
+		for (i = dev_priv->fence_reg_start;
+		     i < dev_priv->num_fence_regs; i++) {
+			reg = &dev_priv->fence_regs[i];
+			old_obj_priv = reg->obj->driver_private;
+			if (!old_obj_priv->pin_count)
+				break;
+		}
+
+		/*
+		 * Now things get ugly... we have to wait for one of the
+		 * objects to finish before trying again.
+		 */
+		if (i == dev_priv->num_fence_regs) {
+			ret = i915_gem_object_wait_rendering(reg->obj);
+			if (ret) {
+				WARN(ret, "wait_rendering failed: %d\n", ret);
+				return;
+			}
+			goto try_again;
+		}
+
+		/*
+		 * Zap this virtual mapping so we can set up a fence again
+		 * for this object next time we need it.
+		 */
+		offset = ((loff_t) reg->obj->map_list.hash.key) << PAGE_SHIFT;
+		unmap_mapping_range(dev->dev_mapping, offset,
+				    reg->obj->size, 1);
+		old_obj_priv->fence_reg = I915_FENCE_REG_NONE;
+	}
+
+	obj_priv->fence_reg = i;
+	reg->obj = obj;
+
+	if (IS_I965G(dev))
+		i965_write_fence_reg(reg);
+	else if (IS_I9XX(dev))
+		i915_write_fence_reg(reg);
+	else
+		i830_write_fence_reg(reg);
+}
+
+/**
+ * i915_gem_clear_fence_reg - clear out fence register info
+ * @obj: object to clear
+ *
+ * Zeroes out the fence register itself and clears out the associated
+ * data structures in dev_priv and obj_priv.
+ */
+static void
+i915_gem_clear_fence_reg(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_i915_gem_object *obj_priv = obj->driver_private;
+
+	if (IS_I965G(dev))
+		I915_WRITE64(FENCE_REG_965_0 + (obj_priv->fence_reg * 8), 0);
+	else
+		I915_WRITE(FENCE_REG_830_0 + (obj_priv->fence_reg * 4), 0);
+
+	dev_priv->fence_regs[obj_priv->fence_reg].obj = NULL;
+	obj_priv->fence_reg = I915_FENCE_REG_NONE;
 }
 
 /**
···
 
 	obj->driver_private = obj_priv;
 	obj_priv->obj = obj;
+	obj_priv->fence_reg = I915_FENCE_REG_NONE;
 	INIT_LIST_HEAD(&obj_priv->list);
+
 	return 0;
 }
 
 void i915_gem_free_object(struct drm_gem_object *obj)
 {
+	struct drm_device *dev = obj->dev;
+	struct drm_gem_mm *mm = dev->mm_private;
+	struct drm_map_list *list;
+	struct drm_map *map;
 	struct drm_i915_gem_object *obj_priv = obj->driver_private;
 
 	while (obj_priv->pin_count > 0)
 		i915_gem_object_unpin(obj);
 
 	i915_gem_object_unbind(obj);
+
+	list = &obj->map_list;
+	drm_ht_remove_item(&mm->offset_hash, &list->hash);
+
+	if (list->file_offset_node) {
+		drm_mm_put_block(list->file_offset_node);
+		list->file_offset_node = NULL;
+	}
+
+	map = list->map;
+	if (map) {
+		drm_free(map, sizeof(*map), DRM_MEM_DRIVER);
+		list->map = NULL;
+	}
 
 	drm_free(obj_priv->page_cpu_valid, 1, DRM_MEM_DRIVER);
 	drm_free(obj->driver_private, 1, DRM_MEM_DRIVER);
···
 	 */
 	i915_gem_flush(dev, ~(I915_GEM_DOMAIN_CPU|I915_GEM_DOMAIN_GTT),
 		       ~(I915_GEM_DOMAIN_CPU|I915_GEM_DOMAIN_GTT));
-	seqno = i915_add_request(dev, ~(I915_GEM_DOMAIN_CPU |
-					I915_GEM_DOMAIN_GTT));
+	seqno = i915_add_request(dev, ~I915_GEM_DOMAIN_CPU);
 
 	if (seqno == 0) {
 		mutex_unlock(&dev->struct_mutex);
···
 	INIT_DELAYED_WORK(&dev_priv->mm.retire_work,
 			  i915_gem_retire_work_handler);
 	dev_priv->mm.next_gem_seqno = 1;
+
+	/* Old X drivers will take 0-2 for front, back, depth buffers */
+	dev_priv->fence_reg_start = 3;
+
+	if (IS_I965G(dev))
+		dev_priv->num_fence_regs = 16;
+	else
+		dev_priv->num_fence_regs = 8;
 
 	i915_gem_detect_bit_6_swizzle(dev);
 }

drivers/gpu/drm/i915/i915_gem_tiling.c

···
 		}
 	}
 	obj_priv->tiling_mode = args->tiling_mode;
+	obj_priv->stride = args->stride;
 
 	mutex_unlock(&dev->struct_mutex);
 

drivers/gpu/drm/i915/i915_reg.h

···
 #define   DISPLAY_PLANE_B           (1<<20)
 
 /*
+ * Fence registers
+ */
+#define FENCE_REG_830_0			0x2000
+#define   I830_FENCE_START_MASK		0x07f80000
+#define   I830_FENCE_TILING_Y_SHIFT	12
+#define   I830_FENCE_SIZE_BITS(size)	((get_order(size >> 19) - 1) << 8)
+#define   I830_FENCE_PITCH_SHIFT	4
+#define   I830_FENCE_REG_VALID		(1<<0)
+
+#define   I915_FENCE_START_MASK		0x0ff00000
+#define   I915_FENCE_SIZE_BITS(size)	((get_order(size >> 20) - 1) << 8)
+
+#define FENCE_REG_965_0			0x03000
+#define   I965_FENCE_PITCH_SHIFT	2
+#define   I965_FENCE_TILING_Y_SHIFT	1
+#define   I965_FENCE_REG_VALID		(1<<0)
+
+/*
  * Instruction and interrupt control regs
  */
-
 #define PRB0_TAIL	0x02030
 #define PRB0_HEAD	0x02034
 #define PRB0_START	0x02038
···
 #define   CM0_DEPTH_WRITE_DISABLE (1<<1)
 #define   CM0_RC_OP_FLUSH_DISABLE (1<<0)
 #define GFX_FLSH_CNTL	0x02170 /* 915+ only */
+
 
 /*
  * Framebuffer compression (915+ only)

include/drm/i915_drm.h

···
 #define DRM_I915_GEM_SET_TILING	0x21
 #define DRM_I915_GEM_GET_TILING	0x22
 #define DRM_I915_GEM_GET_APERTURE 0x23
+#define DRM_I915_GEM_MMAP_GTT	0x24
 
 #define DRM_IOCTL_I915_INIT		DRM_IOW( DRM_COMMAND_BASE + DRM_I915_INIT, drm_i915_init_t)
 #define DRM_IOCTL_I915_FLUSH		DRM_IO ( DRM_COMMAND_BASE + DRM_I915_FLUSH)
···
 #define DRM_IOCTL_I915_GEM_PREAD	DRM_IOW (DRM_COMMAND_BASE + DRM_I915_GEM_PREAD, struct drm_i915_gem_pread)
 #define DRM_IOCTL_I915_GEM_PWRITE	DRM_IOW (DRM_COMMAND_BASE + DRM_I915_GEM_PWRITE, struct drm_i915_gem_pwrite)
 #define DRM_IOCTL_I915_GEM_MMAP		DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_GEM_MMAP, struct drm_i915_gem_mmap)
+#define DRM_IOCTL_I915_GEM_MMAP_GTT	DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_GEM_MMAP_GTT, struct drm_i915_gem_mmap_gtt)
 #define DRM_IOCTL_I915_GEM_SET_DOMAIN	DRM_IOW (DRM_COMMAND_BASE + DRM_I915_GEM_SET_DOMAIN, struct drm_i915_gem_set_domain)
 #define DRM_IOCTL_I915_GEM_SW_FINISH	DRM_IOW (DRM_COMMAND_BASE + DRM_I915_GEM_SW_FINISH, struct drm_i915_gem_sw_finish)
 #define DRM_IOCTL_I915_GEM_SET_TILING	DRM_IOWR (DRM_COMMAND_BASE + DRM_I915_GEM_SET_TILING, struct drm_i915_gem_set_tiling)
···
 	 * This is a fixed-size type for 32/64 compatibility.
 	 */
 	uint64_t addr_ptr;
+};
+
+struct drm_i915_gem_mmap_gtt {
+	/** Handle for the object being mapped. */
+	uint32_t handle;
+	uint32_t pad;
+	/**
+	 * Fake offset to use for subsequent mmap call
+	 *
+	 * This is a fixed-size type for 32/64 compatibility.
+	 */
+	uint64_t offset;
 };
 
 struct drm_i915_gem_set_domain {