Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1518 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
new file mode 100644
index 000000000..da0145bc1
--- /dev/null
+++ b/drivers/gpu/drm/drm_syncobj.c
@@ -0,0 +1,1518 @@
+/*
+ * Copyright 2017 Red Hat
+ * Parts ported from amdgpu (fence wait code).
+ * Copyright 2016 Advanced Micro Devices, Inc.
+ *
+ * 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:
+ *
+ */
+
+/**
+ * DOC: Overview
+ *
+ * DRM synchronisation objects (syncobj, see struct &drm_syncobj) provide a
+ * container for a synchronization primitive which can be used by userspace
+ * to explicitly synchronize GPU commands, can be shared between userspace
+ * processes, and can be shared between different DRM drivers.
+ * Their primary use-case is to implement Vulkan fences and semaphores.
+ * The syncobj userspace API provides ioctls for several operations:
+ *
+ *  - Creation and destruction of syncobjs
+ *  - Import and export of syncobjs to/from a syncobj file descriptor
+ *  - Import and export a syncobj's underlying fence to/from a sync file
+ *  - Reset a syncobj (set its fence to NULL)
+ *  - Signal a syncobj (set a trivially signaled fence)
+ *  - Wait for a syncobj's fence to appear and be signaled
+ *
+ * The syncobj userspace API also provides operations to manipulate a syncobj
+ * in terms of a timeline of struct &dma_fence_chain rather than a single
+ * struct &dma_fence, through the following operations:
+ *
+ *   - Signal a given point on the timeline
+ *   - Wait for a given point to appear and/or be signaled
+ *   - Import and export from/to a given point of a timeline
+ *
+ * At it's core, a syncobj is simply a wrapper around a pointer to a struct
+ * &dma_fence which may be NULL.
+ * When a syncobj is first created, its pointer is either NULL or a pointer
+ * to an already signaled fence depending on whether the
+ * &DRM_SYNCOBJ_CREATE_SIGNALED flag is passed to
+ * &DRM_IOCTL_SYNCOBJ_CREATE.
+ *
+ * If the syncobj is considered as a binary (its state is either signaled or
+ * unsignaled) primitive, when GPU work is enqueued in a DRM driver to signal
+ * the syncobj, the syncobj's fence is replaced with a fence which will be
+ * signaled by the completion of that work.
+ * If the syncobj is considered as a timeline primitive, when GPU work is
+ * enqueued in a DRM driver to signal the a given point of the syncobj, a new
+ * struct &dma_fence_chain pointing to the DRM driver's fence and also
+ * pointing to the previous fence that was in the syncobj. The new struct
+ * &dma_fence_chain fence replace the syncobj's fence and will be signaled by
+ * completion of the DRM driver's work and also any work associated with the
+ * fence previously in the syncobj.
+ *
+ * When GPU work which waits on a syncobj is enqueued in a DRM driver, at the
+ * time the work is enqueued, it waits on the syncobj's fence before
+ * submitting the work to hardware. That fence is either :
+ *
+ *    - The syncobj's current fence if the syncobj is considered as a binary
+ *      primitive.
+ *    - The struct &dma_fence associated with a given point if the syncobj is
+ *      considered as a timeline primitive.
+ *
+ * If the syncobj's fence is NULL or not present in the syncobj's timeline,
+ * the enqueue operation is expected to fail.
+ *
+ * With binary syncobj, all manipulation of the syncobjs's fence happens in
+ * terms of the current fence at the time the ioctl is called by userspace
+ * regardless of whether that operation is an immediate host-side operation
+ * (signal or reset) or or an operation which is enqueued in some driver
+ * queue. &DRM_IOCTL_SYNCOBJ_RESET and &DRM_IOCTL_SYNCOBJ_SIGNAL can be used
+ * to manipulate a syncobj from the host by resetting its pointer to NULL or
+ * setting its pointer to a fence which is already signaled.
+ *
+ * With a timeline syncobj, all manipulation of the synobj's fence happens in
+ * terms of a u64 value referring to point in the timeline. See
+ * dma_fence_chain_find_seqno() to see how a given point is found in the
+ * timeline.
+ *
+ * Note that applications should be careful to always use timeline set of
+ * ioctl() when dealing with syncobj considered as timeline. Using a binary
+ * set of ioctl() with a syncobj considered as timeline could result incorrect
+ * synchronization. The use of binary syncobj is supported through the
+ * timeline set of ioctl() by using a point value of 0, this will reproduce
+ * the behavior of the binary set of ioctl() (for example replace the
+ * syncobj's fence when signaling).
+ *
+ *
+ * Host-side wait on syncobjs
+ * --------------------------
+ *
+ * &DRM_IOCTL_SYNCOBJ_WAIT takes an array of syncobj handles and does a
+ * host-side wait on all of the syncobj fences simultaneously.
+ * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL is set, the wait ioctl will wait on
+ * all of the syncobj fences to be signaled before it returns.
+ * Otherwise, it returns once at least one syncobj fence has been signaled
+ * and the index of a signaled fence is written back to the client.
+ *
+ * Unlike the enqueued GPU work dependencies which fail if they see a NULL
+ * fence in a syncobj, if &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT is set,
+ * the host-side wait will first wait for the syncobj to receive a non-NULL
+ * fence and then wait on that fence.
+ * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT is not set and any one of the
+ * syncobjs in the array has a NULL fence, -EINVAL will be returned.
+ * Assuming the syncobj starts off with a NULL fence, this allows a client
+ * to do a host wait in one thread (or process) which waits on GPU work
+ * submitted in another thread (or process) without having to manually
+ * synchronize between the two.
+ * This requirement is inherited from the Vulkan fence API.
+ *
+ * Similarly, &DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT takes an array of syncobj
+ * handles as well as an array of u64 points and does a host-side wait on all
+ * of syncobj fences at the given points simultaneously.
+ *
+ * &DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT also adds the ability to wait for a given
+ * fence to materialize on the timeline without waiting for the fence to be
+ * signaled by using the &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE flag. This
+ * requirement is inherited from the wait-before-signal behavior required by
+ * the Vulkan timeline semaphore API.
+ *
+ *
+ * Import/export of syncobjs
+ * -------------------------
+ *
+ * &DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE and &DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD
+ * provide two mechanisms for import/export of syncobjs.
+ *
+ * The first lets the client import or export an entire syncobj to a file
+ * descriptor.
+ * These fd's are opaque and have no other use case, except passing the
+ * syncobj between processes.
+ * All exported file descriptors and any syncobj handles created as a
+ * result of importing those file descriptors own a reference to the
+ * same underlying struct &drm_syncobj and the syncobj can be used
+ * persistently across all the processes with which it is shared.
+ * The syncobj is freed only once the last reference is dropped.
+ * Unlike dma-buf, importing a syncobj creates a new handle (with its own
+ * reference) for every import instead of de-duplicating.
+ * The primary use-case of this persistent import/export is for shared
+ * Vulkan fences and semaphores.
+ *
+ * The second import/export mechanism, which is indicated by
+ * &DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE or
+ * &DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE lets the client
+ * import/export the syncobj's current fence from/to a &sync_file.
+ * When a syncobj is exported to a sync file, that sync file wraps the
+ * sycnobj's fence at the time of export and any later signal or reset
+ * operations on the syncobj will not affect the exported sync file.
+ * When a sync file is imported into a syncobj, the syncobj's fence is set
+ * to the fence wrapped by that sync file.
+ * Because sync files are immutable, resetting or signaling the syncobj
+ * will not affect any sync files whose fences have been imported into the
+ * syncobj.
+ *
+ *
+ * Import/export of timeline points in timeline syncobjs
+ * -----------------------------------------------------
+ *
+ * &DRM_IOCTL_SYNCOBJ_TRANSFER provides a mechanism to transfer a struct
+ * &dma_fence_chain of a syncobj at a given u64 point to another u64 point
+ * into another syncobj.
+ *
+ * Note that if you want to transfer a struct &dma_fence_chain from a given
+ * point on a timeline syncobj from/into a binary syncobj, you can use the
+ * point 0 to mean take/replace the fence in the syncobj.
+ */
+
+#include <linux/anon_inodes.h>
+#include <linux/dma-fence-unwrap.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/sched/signal.h>
+#include <linux/sync_file.h>
+#include <linux/uaccess.h>
+
+#include <drm/drm.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_file.h>
+#include <drm/drm_gem.h>
+#include <drm/drm_print.h>
+#include <drm/drm_syncobj.h>
+#include <drm/drm_utils.h>
+
+#include "drm_internal.h"
+
+struct syncobj_wait_entry {
+	struct list_head node;
+	struct task_struct *task;
+	struct dma_fence *fence;
+	struct dma_fence_cb fence_cb;
+	u64    point;
+};
+
+static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
+				      struct syncobj_wait_entry *wait);
+
+/**
+ * drm_syncobj_find - lookup and reference a sync object.
+ * @file_private: drm file private pointer
+ * @handle: sync object handle to lookup.
+ *
+ * Returns a reference to the syncobj pointed to by handle or NULL. The
+ * reference must be released by calling drm_syncobj_put().
+ */
+struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
+				     u32 handle)
+{
+	struct drm_syncobj *syncobj;
+
+	spin_lock(&file_private->syncobj_table_lock);
+
+	/* Check if we currently have a reference on the object */
+	syncobj = idr_find(&file_private->syncobj_idr, handle);
+	if (syncobj)
+		drm_syncobj_get(syncobj);
+
+	spin_unlock(&file_private->syncobj_table_lock);
+
+	return syncobj;
+}
+EXPORT_SYMBOL(drm_syncobj_find);
+
+static void drm_syncobj_fence_add_wait(struct drm_syncobj *syncobj,
+				       struct syncobj_wait_entry *wait)
+{
+	struct dma_fence *fence;
+
+	if (wait->fence)
+		return;
+
+	spin_lock(&syncobj->lock);
+	/* We've already tried once to get a fence and failed.  Now that we
+	 * have the lock, try one more time just to be sure we don't add a
+	 * callback when a fence has already been set.
+	 */
+	fence = dma_fence_get(rcu_dereference_protected(syncobj->fence, 1));
+	if (!fence || dma_fence_chain_find_seqno(&fence, wait->point)) {
+		dma_fence_put(fence);
+		list_add_tail(&wait->node, &syncobj->cb_list);
+	} else if (!fence) {
+		wait->fence = dma_fence_get_stub();
+	} else {
+		wait->fence = fence;
+	}
+	spin_unlock(&syncobj->lock);
+}
+
+static void drm_syncobj_remove_wait(struct drm_syncobj *syncobj,
+				    struct syncobj_wait_entry *wait)
+{
+	if (!wait->node.next)
+		return;
+
+	spin_lock(&syncobj->lock);
+	list_del_init(&wait->node);
+	spin_unlock(&syncobj->lock);
+}
+
+/**
+ * drm_syncobj_add_point - add new timeline point to the syncobj
+ * @syncobj: sync object to add timeline point do
+ * @chain: chain node to use to add the point
+ * @fence: fence to encapsulate in the chain node
+ * @point: sequence number to use for the point
+ *
+ * Add the chain node as new timeline point to the syncobj.
+ */
+void drm_syncobj_add_point(struct drm_syncobj *syncobj,
+			   struct dma_fence_chain *chain,
+			   struct dma_fence *fence,
+			   uint64_t point)
+{
+	struct syncobj_wait_entry *cur, *tmp;
+	struct dma_fence *prev;
+
+	dma_fence_get(fence);
+
+	spin_lock(&syncobj->lock);
+
+	prev = drm_syncobj_fence_get(syncobj);
+	/* You are adding an unorder point to timeline, which could cause payload returned from query_ioctl is 0! */
+	if (prev && prev->seqno >= point)
+		DRM_DEBUG("You are adding an unorder point to timeline!\n");
+	dma_fence_chain_init(chain, prev, fence, point);
+	rcu_assign_pointer(syncobj->fence, &chain->base);
+
+	list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node)
+		syncobj_wait_syncobj_func(syncobj, cur);
+	spin_unlock(&syncobj->lock);
+
+	/* Walk the chain once to trigger garbage collection */
+	dma_fence_chain_for_each(fence, prev);
+	dma_fence_put(prev);
+}
+EXPORT_SYMBOL(drm_syncobj_add_point);
+
+/**
+ * drm_syncobj_replace_fence - replace fence in a sync object.
+ * @syncobj: Sync object to replace fence in
+ * @fence: fence to install in sync file.
+ *
+ * This replaces the fence on a sync object.
+ */
+void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
+			       struct dma_fence *fence)
+{
+	struct dma_fence *old_fence;
+	struct syncobj_wait_entry *cur, *tmp;
+
+	if (fence)
+		dma_fence_get(fence);
+
+	spin_lock(&syncobj->lock);
+
+	old_fence = rcu_dereference_protected(syncobj->fence,
+					      lockdep_is_held(&syncobj->lock));
+	rcu_assign_pointer(syncobj->fence, fence);
+
+	if (fence != old_fence) {
+		list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node)
+			syncobj_wait_syncobj_func(syncobj, cur);
+	}
+
+	spin_unlock(&syncobj->lock);
+
+	dma_fence_put(old_fence);
+}
+EXPORT_SYMBOL(drm_syncobj_replace_fence);
+
+/**
+ * drm_syncobj_assign_null_handle - assign a stub fence to the sync object
+ * @syncobj: sync object to assign the fence on
+ *
+ * Assign a already signaled stub fence to the sync object.
+ */
+static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
+{
+	struct dma_fence *fence = dma_fence_allocate_private_stub(ktime_get());
+
+	if (!fence)
+		return -ENOMEM;
+
+	drm_syncobj_replace_fence(syncobj, fence);
+	dma_fence_put(fence);
+	return 0;
+}
+
+/* 5s default for wait submission */
+#define DRM_SYNCOBJ_WAIT_FOR_SUBMIT_TIMEOUT 5000000000ULL
+/**
+ * drm_syncobj_find_fence - lookup and reference the fence in a sync object
+ * @file_private: drm file private pointer
+ * @handle: sync object handle to lookup.
+ * @point: timeline point
+ * @flags: DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT or not
+ * @fence: out parameter for the fence
+ *
+ * This is just a convenience function that combines drm_syncobj_find() and
+ * drm_syncobj_fence_get().
+ *
+ * Returns 0 on success or a negative error value on failure. On success @fence
+ * contains a reference to the fence, which must be released by calling
+ * dma_fence_put().
+ */
+int drm_syncobj_find_fence(struct drm_file *file_private,
+			   u32 handle, u64 point, u64 flags,
+			   struct dma_fence **fence)
+{
+	struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
+	struct syncobj_wait_entry wait;
+	u64 timeout = nsecs_to_jiffies64(DRM_SYNCOBJ_WAIT_FOR_SUBMIT_TIMEOUT);
+	int ret;
+
+	if (!syncobj)
+		return -ENOENT;
+
+	/* Waiting for userspace with locks help is illegal cause that can
+	 * trivial deadlock with page faults for example. Make lockdep complain
+	 * about it early on.
+	 */
+	if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
+		might_sleep();
+		lockdep_assert_none_held_once();
+	}
+
+	*fence = drm_syncobj_fence_get(syncobj);
+
+	if (*fence) {
+		ret = dma_fence_chain_find_seqno(fence, point);
+		if (!ret) {
+			/* If the requested seqno is already signaled
+			 * drm_syncobj_find_fence may return a NULL
+			 * fence. To make sure the recipient gets
+			 * signalled, use a new fence instead.
+			 */
+			if (!*fence)
+				*fence = dma_fence_get_stub();
+
+			goto out;
+		}
+		dma_fence_put(*fence);
+	} else {
+		ret = -EINVAL;
+	}
+
+	if (!(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
+		goto out;
+
+	memset(&wait, 0, sizeof(wait));
+	wait.task = current;
+	wait.point = point;
+	drm_syncobj_fence_add_wait(syncobj, &wait);
+
+	do {
+		set_current_state(TASK_INTERRUPTIBLE);
+		if (wait.fence) {
+			ret = 0;
+			break;
+		}
+                if (timeout == 0) {
+                        ret = -ETIME;
+                        break;
+                }
+
+		if (signal_pending(current)) {
+			ret = -ERESTARTSYS;
+			break;
+		}
+
+                timeout = schedule_timeout(timeout);
+	} while (1);
+
+	__set_current_state(TASK_RUNNING);
+	*fence = wait.fence;
+
+	if (wait.node.next)
+		drm_syncobj_remove_wait(syncobj, &wait);
+
+out:
+	drm_syncobj_put(syncobj);
+
+	return ret;
+}
+EXPORT_SYMBOL(drm_syncobj_find_fence);
+
+/**
+ * drm_syncobj_free - free a sync object.
+ * @kref: kref to free.
+ *
+ * Only to be called from kref_put in drm_syncobj_put.
+ */
+void drm_syncobj_free(struct kref *kref)
+{
+	struct drm_syncobj *syncobj = container_of(kref,
+						   struct drm_syncobj,
+						   refcount);
+	drm_syncobj_replace_fence(syncobj, NULL);
+	kfree(syncobj);
+}
+EXPORT_SYMBOL(drm_syncobj_free);
+
+/**
+ * drm_syncobj_create - create a new syncobj
+ * @out_syncobj: returned syncobj
+ * @flags: DRM_SYNCOBJ_* flags
+ * @fence: if non-NULL, the syncobj will represent this fence
+ *
+ * This is the first function to create a sync object. After creating, drivers
+ * probably want to make it available to userspace, either through
+ * drm_syncobj_get_handle() or drm_syncobj_get_fd().
+ *
+ * Returns 0 on success or a negative error value on failure.
+ */
+int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
+		       struct dma_fence *fence)
+{
+	int ret;
+	struct drm_syncobj *syncobj;
+
+	syncobj = kzalloc(sizeof(struct drm_syncobj), GFP_KERNEL);
+	if (!syncobj)
+		return -ENOMEM;
+
+	kref_init(&syncobj->refcount);
+	INIT_LIST_HEAD(&syncobj->cb_list);
+	spin_lock_init(&syncobj->lock);
+
+	if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) {
+		ret = drm_syncobj_assign_null_handle(syncobj);
+		if (ret < 0) {
+			drm_syncobj_put(syncobj);
+			return ret;
+		}
+	}
+
+	if (fence)
+		drm_syncobj_replace_fence(syncobj, fence);
+
+	*out_syncobj = syncobj;
+	return 0;
+}
+EXPORT_SYMBOL(drm_syncobj_create);
+
+/**
+ * drm_syncobj_get_handle - get a handle from a syncobj
+ * @file_private: drm file private pointer
+ * @syncobj: Sync object to export
+ * @handle: out parameter with the new handle
+ *
+ * Exports a sync object created with drm_syncobj_create() as a handle on
+ * @file_private to userspace.
+ *
+ * Returns 0 on success or a negative error value on failure.
+ */
+int drm_syncobj_get_handle(struct drm_file *file_private,
+			   struct drm_syncobj *syncobj, u32 *handle)
+{
+	int ret;
+
+	/* take a reference to put in the idr */
+	drm_syncobj_get(syncobj);
+
+	idr_preload(GFP_KERNEL);
+	spin_lock(&file_private->syncobj_table_lock);
+	ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
+	spin_unlock(&file_private->syncobj_table_lock);
+
+	idr_preload_end();
+
+	if (ret < 0) {
+		drm_syncobj_put(syncobj);
+		return ret;
+	}
+
+	*handle = ret;
+	return 0;
+}
+EXPORT_SYMBOL(drm_syncobj_get_handle);
+
+static int drm_syncobj_create_as_handle(struct drm_file *file_private,
+					u32 *handle, uint32_t flags)
+{
+	int ret;
+	struct drm_syncobj *syncobj;
+
+	ret = drm_syncobj_create(&syncobj, flags, NULL);
+	if (ret)
+		return ret;
+
+	ret = drm_syncobj_get_handle(file_private, syncobj, handle);
+	drm_syncobj_put(syncobj);
+	return ret;
+}
+
+static int drm_syncobj_destroy(struct drm_file *file_private,
+			       u32 handle)
+{
+	struct drm_syncobj *syncobj;
+
+	spin_lock(&file_private->syncobj_table_lock);
+	syncobj = idr_remove(&file_private->syncobj_idr, handle);
+	spin_unlock(&file_private->syncobj_table_lock);
+
+	if (!syncobj)
+		return -EINVAL;
+
+	drm_syncobj_put(syncobj);
+	return 0;
+}
+
+static int drm_syncobj_file_release(struct inode *inode, struct file *file)
+{
+	struct drm_syncobj *syncobj = file->private_data;
+
+	drm_syncobj_put(syncobj);
+	return 0;
+}
+
+static const struct file_operations drm_syncobj_file_fops = {
+	.release = drm_syncobj_file_release,
+};
+
+/**
+ * drm_syncobj_get_fd - get a file descriptor from a syncobj
+ * @syncobj: Sync object to export
+ * @p_fd: out parameter with the new file descriptor
+ *
+ * Exports a sync object created with drm_syncobj_create() as a file descriptor.
+ *
+ * Returns 0 on success or a negative error value on failure.
+ */
+int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd)
+{
+	struct file *file;
+	int fd;
+
+	fd = get_unused_fd_flags(O_CLOEXEC);
+	if (fd < 0)
+		return fd;
+
+	file = anon_inode_getfile("syncobj_file",
+				  &drm_syncobj_file_fops,
+				  syncobj, 0);
+	if (IS_ERR(file)) {
+		put_unused_fd(fd);
+		return PTR_ERR(file);
+	}
+
+	drm_syncobj_get(syncobj);
+	fd_install(fd, file);
+
+	*p_fd = fd;
+	return 0;
+}
+EXPORT_SYMBOL(drm_syncobj_get_fd);
+
+static int drm_syncobj_handle_to_fd(struct drm_file *file_private,
+				    u32 handle, int *p_fd)
+{
+	struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
+	int ret;
+
+	if (!syncobj)
+		return -EINVAL;
+
+	ret = drm_syncobj_get_fd(syncobj, p_fd);
+	drm_syncobj_put(syncobj);
+	return ret;
+}
+
+static int drm_syncobj_fd_to_handle(struct drm_file *file_private,
+				    int fd, u32 *handle)
+{
+	struct drm_syncobj *syncobj;
+	struct fd f = fdget(fd);
+	int ret;
+
+	if (!f.file)
+		return -EINVAL;
+
+	if (f.file->f_op != &drm_syncobj_file_fops) {
+		fdput(f);
+		return -EINVAL;
+	}
+
+	/* take a reference to put in the idr */
+	syncobj = f.file->private_data;
+	drm_syncobj_get(syncobj);
+
+	idr_preload(GFP_KERNEL);
+	spin_lock(&file_private->syncobj_table_lock);
+	ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
+	spin_unlock(&file_private->syncobj_table_lock);
+	idr_preload_end();
+
+	if (ret > 0) {
+		*handle = ret;
+		ret = 0;
+	} else
+		drm_syncobj_put(syncobj);
+
+	fdput(f);
+	return ret;
+}
+
+static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
+					      int fd, int handle)
+{
+	struct dma_fence *fence = sync_file_get_fence(fd);
+	struct drm_syncobj *syncobj;
+
+	if (!fence)
+		return -EINVAL;
+
+	syncobj = drm_syncobj_find(file_private, handle);
+	if (!syncobj) {
+		dma_fence_put(fence);
+		return -ENOENT;
+	}
+
+	drm_syncobj_replace_fence(syncobj, fence);
+	dma_fence_put(fence);
+	drm_syncobj_put(syncobj);
+	return 0;
+}
+
+static int drm_syncobj_export_sync_file(struct drm_file *file_private,
+					int handle, int *p_fd)
+{
+	int ret;
+	struct dma_fence *fence;
+	struct sync_file *sync_file;
+	int fd = get_unused_fd_flags(O_CLOEXEC);
+
+	if (fd < 0)
+		return fd;
+
+	ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence);
+	if (ret)
+		goto err_put_fd;
+
+	sync_file = sync_file_create(fence);
+
+	dma_fence_put(fence);
+
+	if (!sync_file) {
+		ret = -EINVAL;
+		goto err_put_fd;
+	}
+
+	fd_install(fd, sync_file->file);
+
+	*p_fd = fd;
+	return 0;
+err_put_fd:
+	put_unused_fd(fd);
+	return ret;
+}
+/**
+ * drm_syncobj_open - initializes syncobj file-private structures at devnode open time
+ * @file_private: drm file-private structure to set up
+ *
+ * Called at device open time, sets up the structure for handling refcounting
+ * of sync objects.
+ */
+void
+drm_syncobj_open(struct drm_file *file_private)
+{
+	idr_init_base(&file_private->syncobj_idr, 1);
+	spin_lock_init(&file_private->syncobj_table_lock);
+}
+
+static int
+drm_syncobj_release_handle(int id, void *ptr, void *data)
+{
+	struct drm_syncobj *syncobj = ptr;
+
+	drm_syncobj_put(syncobj);
+	return 0;
+}
+
+/**
+ * drm_syncobj_release - release file-private sync object resources
+ * @file_private: drm file-private structure to clean up
+ *
+ * Called at close time when the filp is going away.
+ *
+ * Releases any remaining references on objects by this filp.
+ */
+void
+drm_syncobj_release(struct drm_file *file_private)
+{
+	idr_for_each(&file_private->syncobj_idr,
+		     &drm_syncobj_release_handle, file_private);
+	idr_destroy(&file_private->syncobj_idr);
+}
+
+int
+drm_syncobj_create_ioctl(struct drm_device *dev, void *data,
+			 struct drm_file *file_private)
+{
+	struct drm_syncobj_create *args = data;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
+		return -EOPNOTSUPP;
+
+	/* no valid flags yet */
+	if (args->flags & ~DRM_SYNCOBJ_CREATE_SIGNALED)
+		return -EINVAL;
+
+	return drm_syncobj_create_as_handle(file_private,
+					    &args->handle, args->flags);
+}
+
+int
+drm_syncobj_destroy_ioctl(struct drm_device *dev, void *data,
+			  struct drm_file *file_private)
+{
+	struct drm_syncobj_destroy *args = data;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
+		return -EOPNOTSUPP;
+
+	/* make sure padding is empty */
+	if (args->pad)
+		return -EINVAL;
+	return drm_syncobj_destroy(file_private, args->handle);
+}
+
+int
+drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
+				   struct drm_file *file_private)
+{
+	struct drm_syncobj_handle *args = data;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
+		return -EOPNOTSUPP;
+
+	if (args->pad)
+		return -EINVAL;
+
+	if (args->flags != 0 &&
+	    args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
+		return -EINVAL;
+
+	if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
+		return drm_syncobj_export_sync_file(file_private, args->handle,
+						    &args->fd);
+
+	return drm_syncobj_handle_to_fd(file_private, args->handle,
+					&args->fd);
+}
+
+int
+drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data,
+				   struct drm_file *file_private)
+{
+	struct drm_syncobj_handle *args = data;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
+		return -EOPNOTSUPP;
+
+	if (args->pad)
+		return -EINVAL;
+
+	if (args->flags != 0 &&
+	    args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
+		return -EINVAL;
+
+	if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
+		return drm_syncobj_import_sync_file_fence(file_private,
+							  args->fd,
+							  args->handle);
+
+	return drm_syncobj_fd_to_handle(file_private, args->fd,
+					&args->handle);
+}
+
+static int drm_syncobj_transfer_to_timeline(struct drm_file *file_private,
+					    struct drm_syncobj_transfer *args)
+{
+	struct drm_syncobj *timeline_syncobj = NULL;
+	struct dma_fence *fence, *tmp;
+	struct dma_fence_chain *chain;
+	int ret;
+
+	timeline_syncobj = drm_syncobj_find(file_private, args->dst_handle);
+	if (!timeline_syncobj) {
+		return -ENOENT;
+	}
+	ret = drm_syncobj_find_fence(file_private, args->src_handle,
+				     args->src_point, args->flags,
+				     &tmp);
+	if (ret)
+		goto err_put_timeline;
+
+	fence = dma_fence_unwrap_merge(tmp);
+	dma_fence_put(tmp);
+	if (!fence) {
+		ret = -ENOMEM;
+		goto err_put_timeline;
+	}
+
+	chain = dma_fence_chain_alloc();
+	if (!chain) {
+		ret = -ENOMEM;
+		goto err_free_fence;
+	}
+
+	drm_syncobj_add_point(timeline_syncobj, chain, fence, args->dst_point);
+err_free_fence:
+	dma_fence_put(fence);
+err_put_timeline:
+	drm_syncobj_put(timeline_syncobj);
+
+	return ret;
+}
+
+static int
+drm_syncobj_transfer_to_binary(struct drm_file *file_private,
+			       struct drm_syncobj_transfer *args)
+{
+	struct drm_syncobj *binary_syncobj = NULL;
+	struct dma_fence *fence;
+	int ret;
+
+	binary_syncobj = drm_syncobj_find(file_private, args->dst_handle);
+	if (!binary_syncobj)
+		return -ENOENT;
+	ret = drm_syncobj_find_fence(file_private, args->src_handle,
+				     args->src_point, args->flags, &fence);
+	if (ret)
+		goto err;
+	drm_syncobj_replace_fence(binary_syncobj, fence);
+	dma_fence_put(fence);
+err:
+	drm_syncobj_put(binary_syncobj);
+
+	return ret;
+}
+int
+drm_syncobj_transfer_ioctl(struct drm_device *dev, void *data,
+			   struct drm_file *file_private)
+{
+	struct drm_syncobj_transfer *args = data;
+	int ret;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
+		return -EOPNOTSUPP;
+
+	if (args->pad)
+		return -EINVAL;
+
+	if (args->dst_point)
+		ret = drm_syncobj_transfer_to_timeline(file_private, args);
+	else
+		ret = drm_syncobj_transfer_to_binary(file_private, args);
+
+	return ret;
+}
+
+static void syncobj_wait_fence_func(struct dma_fence *fence,
+				    struct dma_fence_cb *cb)
+{
+	struct syncobj_wait_entry *wait =
+		container_of(cb, struct syncobj_wait_entry, fence_cb);
+
+	wake_up_process(wait->task);
+}
+
+static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
+				      struct syncobj_wait_entry *wait)
+{
+	struct dma_fence *fence;
+
+	/* This happens inside the syncobj lock */
+	fence = rcu_dereference_protected(syncobj->fence,
+					  lockdep_is_held(&syncobj->lock));
+	dma_fence_get(fence);
+	if (!fence || dma_fence_chain_find_seqno(&fence, wait->point)) {
+		dma_fence_put(fence);
+		return;
+	} else if (!fence) {
+		wait->fence = dma_fence_get_stub();
+	} else {
+		wait->fence = fence;
+	}
+
+	wake_up_process(wait->task);
+	list_del_init(&wait->node);
+}
+
+static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
+						  void __user *user_points,
+						  uint32_t count,
+						  uint32_t flags,
+						  signed long timeout,
+						  uint32_t *idx)
+{
+	struct syncobj_wait_entry *entries;
+	struct dma_fence *fence;
+	uint64_t *points;
+	uint32_t signaled_count, i;
+
+	if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT)
+		lockdep_assert_none_held_once();
+
+	points = kmalloc_array(count, sizeof(*points), GFP_KERNEL);
+	if (points == NULL)
+		return -ENOMEM;
+
+	if (!user_points) {
+		memset(points, 0, count * sizeof(uint64_t));
+
+	} else if (copy_from_user(points, user_points,
+				  sizeof(uint64_t) * count)) {
+		timeout = -EFAULT;
+		goto err_free_points;
+	}
+
+	entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
+	if (!entries) {
+		timeout = -ENOMEM;
+		goto err_free_points;
+	}
+	/* Walk the list of sync objects and initialize entries.  We do
+	 * this up-front so that we can properly return -EINVAL if there is
+	 * a syncobj with a missing fence and then never have the chance of
+	 * returning -EINVAL again.
+	 */
+	signaled_count = 0;
+	for (i = 0; i < count; ++i) {
+		struct dma_fence *fence;
+
+		entries[i].task = current;
+		entries[i].point = points[i];
+		fence = drm_syncobj_fence_get(syncobjs[i]);
+		if (!fence || dma_fence_chain_find_seqno(&fence, points[i])) {
+			dma_fence_put(fence);
+			if (flags & (DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
+				     DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE)) {
+				continue;
+			} else {
+				timeout = -EINVAL;
+				goto cleanup_entries;
+			}
+		}
+
+		if (fence)
+			entries[i].fence = fence;
+		else
+			entries[i].fence = dma_fence_get_stub();
+
+		if ((flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) ||
+		    dma_fence_is_signaled(entries[i].fence)) {
+			if (signaled_count == 0 && idx)
+				*idx = i;
+			signaled_count++;
+		}
+	}
+
+	if (signaled_count == count ||
+	    (signaled_count > 0 &&
+	     !(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL)))
+		goto cleanup_entries;
+
+	/* There's a very annoying laxness in the dma_fence API here, in
+	 * that backends are not required to automatically report when a
+	 * fence is signaled prior to fence->ops->enable_signaling() being
+	 * called.  So here if we fail to match signaled_count, we need to
+	 * fallthough and try a 0 timeout wait!
+	 */
+
+	if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
+		for (i = 0; i < count; ++i)
+			drm_syncobj_fence_add_wait(syncobjs[i], &entries[i]);
+	}
+
+	do {
+		set_current_state(TASK_INTERRUPTIBLE);
+
+		signaled_count = 0;
+		for (i = 0; i < count; ++i) {
+			fence = entries[i].fence;
+			if (!fence)
+				continue;
+
+			if ((flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) ||
+			    dma_fence_is_signaled(fence) ||
+			    (!entries[i].fence_cb.func &&
+			     dma_fence_add_callback(fence,
+						    &entries[i].fence_cb,
+						    syncobj_wait_fence_func))) {
+				/* The fence has been signaled */
+				if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) {
+					signaled_count++;
+				} else {
+					if (idx)
+						*idx = i;
+					goto done_waiting;
+				}
+			}
+		}
+
+		if (signaled_count == count)
+			goto done_waiting;
+
+		if (timeout == 0) {
+			timeout = -ETIME;
+			goto done_waiting;
+		}
+
+		if (signal_pending(current)) {
+			timeout = -ERESTARTSYS;
+			goto done_waiting;
+		}
+
+		timeout = schedule_timeout(timeout);
+	} while (1);
+
+done_waiting:
+	__set_current_state(TASK_RUNNING);
+
+cleanup_entries:
+	for (i = 0; i < count; ++i) {
+		drm_syncobj_remove_wait(syncobjs[i], &entries[i]);
+		if (entries[i].fence_cb.func)
+			dma_fence_remove_callback(entries[i].fence,
+						  &entries[i].fence_cb);
+		dma_fence_put(entries[i].fence);
+	}
+	kfree(entries);
+
+err_free_points:
+	kfree(points);
+
+	return timeout;
+}
+
+/**
+ * drm_timeout_abs_to_jiffies - calculate jiffies timeout from absolute value
+ *
+ * @timeout_nsec: timeout nsec component in ns, 0 for poll
+ *
+ * Calculate the timeout in jiffies from an absolute time in sec/nsec.
+ */
+signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec)
+{
+	ktime_t abs_timeout, now;
+	u64 timeout_ns, timeout_jiffies64;
+
+	/* make 0 timeout means poll - absolute 0 doesn't seem valid */
+	if (timeout_nsec == 0)
+		return 0;
+
+	abs_timeout = ns_to_ktime(timeout_nsec);
+	now = ktime_get();
+
+	if (!ktime_after(abs_timeout, now))
+		return 0;
+
+	timeout_ns = ktime_to_ns(ktime_sub(abs_timeout, now));
+
+	timeout_jiffies64 = nsecs_to_jiffies64(timeout_ns);
+	/*  clamp timeout to avoid infinite timeout */
+	if (timeout_jiffies64 >= MAX_SCHEDULE_TIMEOUT - 1)
+		return MAX_SCHEDULE_TIMEOUT - 1;
+
+	return timeout_jiffies64 + 1;
+}
+EXPORT_SYMBOL(drm_timeout_abs_to_jiffies);
+
+static int drm_syncobj_array_wait(struct drm_device *dev,
+				  struct drm_file *file_private,
+				  struct drm_syncobj_wait *wait,
+				  struct drm_syncobj_timeline_wait *timeline_wait,
+				  struct drm_syncobj **syncobjs, bool timeline)
+{
+	signed long timeout = 0;
+	uint32_t first = ~0;
+
+	if (!timeline) {
+		timeout = drm_timeout_abs_to_jiffies(wait->timeout_nsec);
+		timeout = drm_syncobj_array_wait_timeout(syncobjs,
+							 NULL,
+							 wait->count_handles,
+							 wait->flags,
+							 timeout, &first);
+		if (timeout < 0)
+			return timeout;
+		wait->first_signaled = first;
+	} else {
+		timeout = drm_timeout_abs_to_jiffies(timeline_wait->timeout_nsec);
+		timeout = drm_syncobj_array_wait_timeout(syncobjs,
+							 u64_to_user_ptr(timeline_wait->points),
+							 timeline_wait->count_handles,
+							 timeline_wait->flags,
+							 timeout, &first);
+		if (timeout < 0)
+			return timeout;
+		timeline_wait->first_signaled = first;
+	}
+	return 0;
+}
+
+static int drm_syncobj_array_find(struct drm_file *file_private,
+				  void __user *user_handles,
+				  uint32_t count_handles,
+				  struct drm_syncobj ***syncobjs_out)
+{
+	uint32_t i, *handles;
+	struct drm_syncobj **syncobjs;
+	int ret;
+
+	handles = kmalloc_array(count_handles, sizeof(*handles), GFP_KERNEL);
+	if (handles == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(handles, user_handles,
+			   sizeof(uint32_t) * count_handles)) {
+		ret = -EFAULT;
+		goto err_free_handles;
+	}
+
+	syncobjs = kmalloc_array(count_handles, sizeof(*syncobjs), GFP_KERNEL);
+	if (syncobjs == NULL) {
+		ret = -ENOMEM;
+		goto err_free_handles;
+	}
+
+	for (i = 0; i < count_handles; i++) {
+		syncobjs[i] = drm_syncobj_find(file_private, handles[i]);
+		if (!syncobjs[i]) {
+			ret = -ENOENT;
+			goto err_put_syncobjs;
+		}
+	}
+
+	kfree(handles);
+	*syncobjs_out = syncobjs;
+	return 0;
+
+err_put_syncobjs:
+	while (i-- > 0)
+		drm_syncobj_put(syncobjs[i]);
+	kfree(syncobjs);
+err_free_handles:
+	kfree(handles);
+
+	return ret;
+}
+
+static void drm_syncobj_array_free(struct drm_syncobj **syncobjs,
+				   uint32_t count)
+{
+	uint32_t i;
+
+	for (i = 0; i < count; i++)
+		drm_syncobj_put(syncobjs[i]);
+	kfree(syncobjs);
+}
+
+int
+drm_syncobj_wait_ioctl(struct drm_device *dev, void *data,
+		       struct drm_file *file_private)
+{
+	struct drm_syncobj_wait *args = data;
+	struct drm_syncobj **syncobjs;
+	int ret = 0;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
+		return -EOPNOTSUPP;
+
+	if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
+			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
+		return -EINVAL;
+
+	if (args->count_handles == 0)
+		return -EINVAL;
+
+	ret = drm_syncobj_array_find(file_private,
+				     u64_to_user_ptr(args->handles),
+				     args->count_handles,
+				     &syncobjs);
+	if (ret < 0)
+		return ret;
+
+	ret = drm_syncobj_array_wait(dev, file_private,
+				     args, NULL, syncobjs, false);
+
+	drm_syncobj_array_free(syncobjs, args->count_handles);
+
+	return ret;
+}
+
+int
+drm_syncobj_timeline_wait_ioctl(struct drm_device *dev, void *data,
+				struct drm_file *file_private)
+{
+	struct drm_syncobj_timeline_wait *args = data;
+	struct drm_syncobj **syncobjs;
+	int ret = 0;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
+		return -EOPNOTSUPP;
+
+	if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
+			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
+			    DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE))
+		return -EINVAL;
+
+	if (args->count_handles == 0)
+		return -EINVAL;
+
+	ret = drm_syncobj_array_find(file_private,
+				     u64_to_user_ptr(args->handles),
+				     args->count_handles,
+				     &syncobjs);
+	if (ret < 0)
+		return ret;
+
+	ret = drm_syncobj_array_wait(dev, file_private,
+				     NULL, args, syncobjs, true);
+
+	drm_syncobj_array_free(syncobjs, args->count_handles);
+
+	return ret;
+}
+
+
+int
+drm_syncobj_reset_ioctl(struct drm_device *dev, void *data,
+			struct drm_file *file_private)
+{
+	struct drm_syncobj_array *args = data;
+	struct drm_syncobj **syncobjs;
+	uint32_t i;
+	int ret;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
+		return -EOPNOTSUPP;
+
+	if (args->pad != 0)
+		return -EINVAL;
+
+	if (args->count_handles == 0)
+		return -EINVAL;
+
+	ret = drm_syncobj_array_find(file_private,
+				     u64_to_user_ptr(args->handles),
+				     args->count_handles,
+				     &syncobjs);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < args->count_handles; i++)
+		drm_syncobj_replace_fence(syncobjs[i], NULL);
+
+	drm_syncobj_array_free(syncobjs, args->count_handles);
+
+	return 0;
+}
+
+int
+drm_syncobj_signal_ioctl(struct drm_device *dev, void *data,
+			 struct drm_file *file_private)
+{
+	struct drm_syncobj_array *args = data;
+	struct drm_syncobj **syncobjs;
+	uint32_t i;
+	int ret;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
+		return -EOPNOTSUPP;
+
+	if (args->pad != 0)
+		return -EINVAL;
+
+	if (args->count_handles == 0)
+		return -EINVAL;
+
+	ret = drm_syncobj_array_find(file_private,
+				     u64_to_user_ptr(args->handles),
+				     args->count_handles,
+				     &syncobjs);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < args->count_handles; i++) {
+		ret = drm_syncobj_assign_null_handle(syncobjs[i]);
+		if (ret < 0)
+			break;
+	}
+
+	drm_syncobj_array_free(syncobjs, args->count_handles);
+
+	return ret;
+}
+
+int
+drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
+				  struct drm_file *file_private)
+{
+	struct drm_syncobj_timeline_array *args = data;
+	struct drm_syncobj **syncobjs;
+	struct dma_fence_chain **chains;
+	uint64_t *points;
+	uint32_t i, j;
+	int ret;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
+		return -EOPNOTSUPP;
+
+	if (args->flags != 0)
+		return -EINVAL;
+
+	if (args->count_handles == 0)
+		return -EINVAL;
+
+	ret = drm_syncobj_array_find(file_private,
+				     u64_to_user_ptr(args->handles),
+				     args->count_handles,
+				     &syncobjs);
+	if (ret < 0)
+		return ret;
+
+	points = kmalloc_array(args->count_handles, sizeof(*points),
+			       GFP_KERNEL);
+	if (!points) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	if (!u64_to_user_ptr(args->points)) {
+		memset(points, 0, args->count_handles * sizeof(uint64_t));
+	} else if (copy_from_user(points, u64_to_user_ptr(args->points),
+				  sizeof(uint64_t) * args->count_handles)) {
+		ret = -EFAULT;
+		goto err_points;
+	}
+
+	chains = kmalloc_array(args->count_handles, sizeof(void *), GFP_KERNEL);
+	if (!chains) {
+		ret = -ENOMEM;
+		goto err_points;
+	}
+	for (i = 0; i < args->count_handles; i++) {
+		chains[i] = dma_fence_chain_alloc();
+		if (!chains[i]) {
+			for (j = 0; j < i; j++)
+				dma_fence_chain_free(chains[j]);
+			ret = -ENOMEM;
+			goto err_chains;
+		}
+	}
+
+	for (i = 0; i < args->count_handles; i++) {
+		struct dma_fence *fence = dma_fence_get_stub();
+
+		drm_syncobj_add_point(syncobjs[i], chains[i],
+				      fence, points[i]);
+		dma_fence_put(fence);
+	}
+err_chains:
+	kfree(chains);
+err_points:
+	kfree(points);
+out:
+	drm_syncobj_array_free(syncobjs, args->count_handles);
+
+	return ret;
+}
+
+int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
+			    struct drm_file *file_private)
+{
+	struct drm_syncobj_timeline_array *args = data;
+	struct drm_syncobj **syncobjs;
+	uint64_t __user *points = u64_to_user_ptr(args->points);
+	uint32_t i;
+	int ret;
+
+	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
+		return -EOPNOTSUPP;
+
+	if (args->flags & ~DRM_SYNCOBJ_QUERY_FLAGS_LAST_SUBMITTED)
+		return -EINVAL;
+
+	if (args->count_handles == 0)
+		return -EINVAL;
+
+	ret = drm_syncobj_array_find(file_private,
+				     u64_to_user_ptr(args->handles),
+				     args->count_handles,
+				     &syncobjs);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < args->count_handles; i++) {
+		struct dma_fence_chain *chain;
+		struct dma_fence *fence;
+		uint64_t point;
+
+		fence = drm_syncobj_fence_get(syncobjs[i]);
+		chain = to_dma_fence_chain(fence);
+		if (chain) {
+			struct dma_fence *iter, *last_signaled =
+				dma_fence_get(fence);
+
+			if (args->flags &
+			    DRM_SYNCOBJ_QUERY_FLAGS_LAST_SUBMITTED) {
+				point = fence->seqno;
+			} else {
+				dma_fence_chain_for_each(iter, fence) {
+					if (iter->context != fence->context) {
+						dma_fence_put(iter);
+						/* It is most likely that timeline has
+						* unorder points. */
+						break;
+					}
+					dma_fence_put(last_signaled);
+					last_signaled = dma_fence_get(iter);
+				}
+				point = dma_fence_is_signaled(last_signaled) ?
+					last_signaled->seqno :
+					to_dma_fence_chain(last_signaled)->prev_seqno;
+			}
+			dma_fence_put(last_signaled);
+		} else {
+			point = 0;
+		}
+		dma_fence_put(fence);
+		ret = copy_to_user(&points[i], &point, sizeof(uint64_t));
+		ret = ret ? -EFAULT : 0;
+		if (ret)
+			break;
+	}
+	drm_syncobj_array_free(syncobjs, args->count_handles);
+
+	return ret;
+}