drivers/gpu/drm/nouveau/nvkm/engine/fifo/uchan.c - linux - Git at Google

 /*
  * Copyright 2021 Red Hat 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
  */
 #define nvkm_uchan(p) container_of((p), struct nvkm_uchan, object)
 #include "priv.h"
 #include "cgrp.h"
 #include "chan.h"
 #include "chid.h"
 #include "runl.h"

 #include <core/gpuobj.h>
 #include <core/oproxy.h>
 #include <subdev/mmu.h>
 #include <engine/dma.h>

 #include <nvif/if0020.h>

 struct nvkm_uchan {
 	struct nvkm_object object;
 	struct nvkm_chan *chan;
 };

 static int
 nvkm_uchan_uevent(struct nvkm_object *object, void *argv, u32 argc, struct nvkm_uevent *uevent)
 {
 	struct nvkm_chan *chan = nvkm_uchan(object)->chan;
 	struct nvkm_runl *runl = chan->cgrp->runl;
 	union nvif_chan_event_args *args = argv;

 	if (!uevent)
 		return 0;
 	if (argc != sizeof(args->v0) || args->v0.version != 0)
 		return -ENOSYS;

 	switch (args->v0.type) {
 	case NVIF_CHAN_EVENT_V0_NON_STALL_INTR:
 		return nvkm_uevent_add(uevent, &runl->fifo->nonstall.event, runl->id,
 				       NVKM_FIFO_NONSTALL_EVENT, NULL);
 	case NVIF_CHAN_EVENT_V0_KILLED:
 		return nvkm_uevent_add(uevent, &runl->chid->event, chan->id,
 				       NVKM_CHAN_EVENT_ERRORED, NULL);
 	default:
 		break;
 	}

 	return -ENOSYS;
 }

 struct nvkm_uobj {
 	struct nvkm_oproxy oproxy;
 	struct nvkm_chan *chan;
 	struct nvkm_cctx *cctx;
 	int hash;
 };

 static int
 nvkm_uchan_object_fini_1(struct nvkm_oproxy *oproxy, bool suspend)
 {
 	struct nvkm_uobj *uobj = container_of(oproxy, typeof(*uobj), oproxy);
 	struct nvkm_chan *chan = uobj->chan;
 	struct nvkm_cctx *cctx = uobj->cctx;
 	struct nvkm_ectx *ectx = cctx->vctx->ectx;

 	if (!ectx->object)
 		return 0;

 	/* Unbind engine context from channel, if no longer required. */
 	if (refcount_dec_and_mutex_lock(&cctx->uses, &chan->cgrp->mutex)) {
 		nvkm_chan_cctx_bind(chan, ectx->engn, NULL);

 		if (refcount_dec_and_test(&ectx->uses))
 			nvkm_object_fini(ectx->object, false);
 		mutex_unlock(&chan->cgrp->mutex);
 	}

 	return 0;
 }

 static int
 nvkm_uchan_object_init_0(struct nvkm_oproxy *oproxy)
 {
 	struct nvkm_uobj *uobj = container_of(oproxy, typeof(*uobj), oproxy);
 	struct nvkm_chan *chan = uobj->chan;
 	struct nvkm_cctx *cctx = uobj->cctx;
 	struct nvkm_ectx *ectx = cctx->vctx->ectx;
 	int ret = 0;

 	if (!ectx->object)
 		return 0;

 	/* Bind engine context to channel, if it hasn't been already. */
 	if (!refcount_inc_not_zero(&cctx->uses)) {
 		mutex_lock(&chan->cgrp->mutex);
 		if (!refcount_inc_not_zero(&cctx->uses)) {
 			if (!refcount_inc_not_zero(&ectx->uses)) {
 				ret = nvkm_object_init(ectx->object);
 				if (ret == 0)
 					refcount_set(&ectx->uses, 1);
 			}

 			if (ret == 0) {
 				nvkm_chan_cctx_bind(chan, ectx->engn, cctx);
 				refcount_set(&cctx->uses, 1);
 			}
 		}
 		mutex_unlock(&chan->cgrp->mutex);
 	}

 	return ret;
 }

 static void
 nvkm_uchan_object_dtor(struct nvkm_oproxy *oproxy)
 {
 	struct nvkm_uobj *uobj = container_of(oproxy, typeof(*uobj), oproxy);
 	struct nvkm_engn *engn;

 	if (!uobj->cctx)
 		return;

 	engn = uobj->cctx->vctx->ectx->engn;
 	if (engn->func->ramht_del)
 		engn->func->ramht_del(uobj->chan, uobj->hash);

 	nvkm_chan_cctx_put(uobj->chan, &uobj->cctx);
 }

 static const struct nvkm_oproxy_func
 nvkm_uchan_object = {
 	.dtor[1] = nvkm_uchan_object_dtor,
 	.init[0] = nvkm_uchan_object_init_0,
 	.fini[1] = nvkm_uchan_object_fini_1,
 };

 static int
 nvkm_uchan_object_new(const struct nvkm_oclass *oclass, void *argv, u32 argc,
 		      struct nvkm_object **pobject)
 {
 	struct nvkm_chan *chan = nvkm_uchan(oclass->parent)->chan;
 	struct nvkm_cgrp *cgrp = chan->cgrp;
 	struct nvkm_engn *engn;
 	struct nvkm_uobj *uobj;
 	int ret;

 	/* Lookup host engine state for target engine. */
 	engn = nvkm_runl_find_engn(engn, cgrp->runl, engn->engine == oclass->engine);
 	if (WARN_ON(!engn))
 		return -EINVAL;

 	/* Allocate SW object. */
 	if (!(uobj = kzalloc(sizeof(*uobj), GFP_KERNEL)))
 		return -ENOMEM;

 	nvkm_oproxy_ctor(&nvkm_uchan_object, oclass, &uobj->oproxy);
 	uobj->chan = chan;
 	*pobject = &uobj->oproxy.base;

 	/* Ref. channel context for target engine.*/
 	ret = nvkm_chan_cctx_get(chan, engn, &uobj->cctx, oclass->client);
 	if (ret)
 		return ret;

 	/* Allocate HW object. */
 	ret = oclass->base.ctor(&(const struct nvkm_oclass) {
 					.base = oclass->base,
 					.engn = oclass->engn,
 					.handle = oclass->handle,
 					.object = oclass->object,
 					.client = oclass->client,
 					.parent = uobj->cctx->vctx->ectx->object ?: oclass->parent,
 					.engine = engn->engine,
 				 }, argv, argc, &uobj->oproxy.object);
 	if (ret)
 		return ret;

 	if (engn->func->ramht_add) {
 		uobj->hash = engn->func->ramht_add(engn, uobj->oproxy.object, uobj->chan);
 		if (uobj->hash < 0)
 			return uobj->hash;
 	}

 	return 0;
 }

 static int
 nvkm_uchan_sclass(struct nvkm_object *object, int index, struct nvkm_oclass *oclass)
 {
 	struct nvkm_chan *chan = nvkm_uchan(object)->chan;
 	struct nvkm_engn *engn;
 	int ret, runq = 0;

 	nvkm_runl_foreach_engn(engn, chan->cgrp->runl) {
 		struct nvkm_engine *engine = engn->engine;
 		int c = 0;

 		/* Each runqueue, on runlists with multiple, has its own LCE. */
 		if (engn->runl->func->runqs) {
 			if (engine->subdev.type == NVKM_ENGINE_CE) {
 				if (chan->runq != runq++)
 					continue;
 			}
 		}

 		oclass->engine = engine;
 		oclass->base.oclass = 0;

 		if (engine->func->fifo.sclass) {
 			ret = engine->func->fifo.sclass(oclass, index);
 			if (oclass->base.oclass) {
 				if (!oclass->base.ctor)
 					oclass->base.ctor = nvkm_object_new;
 				oclass->ctor = nvkm_uchan_object_new;
 				return 0;
 			}

 			index -= ret;
 			continue;
 		}

 		while (engine->func->sclass[c].oclass) {
 			if (c++ == index) {
 				oclass->base = engine->func->sclass[index];
 				if (!oclass->base.ctor)
 					oclass->base.ctor = nvkm_object_new;
 				oclass->ctor = nvkm_uchan_object_new;
 				return 0;
 			}
 		}

 		index -= c;
 	}

 	return -EINVAL;
 }

 static int
 nvkm_uchan_map(struct nvkm_object *object, void *argv, u32 argc,
 	       enum nvkm_object_map *type, u64 *addr, u64 *size)
 {
 	struct nvkm_chan *chan = nvkm_uchan(object)->chan;
 	struct nvkm_device *device = chan->cgrp->runl->fifo->engine.subdev.device;

 	if (chan->func->userd->bar < 0)
 		return -ENOSYS;

 	*type = NVKM_OBJECT_MAP_IO;
 	*addr = device->func->resource_addr(device, chan->func->userd->bar) +
 		chan->func->userd->base + chan->userd.base;
 	*size = chan->func->userd->size;
 	return 0;
 }

 static int
 nvkm_uchan_fini(struct nvkm_object *object, bool suspend)
 {
 	struct nvkm_chan *chan = nvkm_uchan(object)->chan;

 	nvkm_chan_block(chan);
 	nvkm_chan_remove(chan, true);

 	if (chan->func->unbind)
 		chan->func->unbind(chan);

 	return 0;
 }

 static int
 nvkm_uchan_init(struct nvkm_object *object)
 {
 	struct nvkm_chan *chan = nvkm_uchan(object)->chan;

 	if (atomic_read(&chan->errored))
 		return 0;

 	if (chan->func->bind)
 		chan->func->bind(chan);

 	nvkm_chan_allow(chan);
 	nvkm_chan_insert(chan);
 	return 0;
 }

 static void *
 nvkm_uchan_dtor(struct nvkm_object *object)
 {
 	struct nvkm_uchan *uchan = nvkm_uchan(object);

 	nvkm_chan_del(&uchan->chan);
 	return uchan;
 }

 static const struct nvkm_object_func
 nvkm_uchan = {
 	.dtor = nvkm_uchan_dtor,
 	.init = nvkm_uchan_init,
 	.fini = nvkm_uchan_fini,
 	.map = nvkm_uchan_map,
 	.sclass = nvkm_uchan_sclass,
 	.uevent = nvkm_uchan_uevent,
 };

 struct nvkm_chan *
 nvkm_uchan_chan(struct nvkm_object *object)
 {
 	if (WARN_ON(object->func != &nvkm_uchan))
 		return NULL;

 	return nvkm_uchan(object)->chan;
 }

 int
 nvkm_uchan_new(struct nvkm_fifo *fifo, struct nvkm_cgrp *cgrp, const struct nvkm_oclass *oclass,
 	       void *argv, u32 argc, struct nvkm_object **pobject)
 {
 	union nvif_chan_args *args = argv;
 	struct nvkm_runl *runl;
 	struct nvkm_vmm *vmm = NULL;
 	struct nvkm_dmaobj *ctxdma = NULL;
 	struct nvkm_memory *userd = NULL;
 	struct nvkm_uchan *uchan;
 	struct nvkm_chan *chan;
 	int ret;

 	if (argc < sizeof(args->v0) || args->v0.version != 0)
 		return -ENOSYS;
 	argc -= sizeof(args->v0);

 	if (args->v0.namelen != argc)
 		return -EINVAL;

 	/* Lookup objects referenced in args. */
 	runl = nvkm_runl_get(fifo, args->v0.runlist, 0);
 	if (!runl)
 		return -EINVAL;

 	if (args->v0.vmm) {
 		vmm = nvkm_uvmm_search(oclass->client, args->v0.vmm);
 		if (IS_ERR(vmm))
 			return PTR_ERR(vmm);
 	}

 	if (args->v0.ctxdma) {
 		ctxdma = nvkm_dmaobj_search(oclass->client, args->v0.ctxdma);
 		if (IS_ERR(ctxdma)) {
 			ret = PTR_ERR(ctxdma);
 			goto done;
 		}
 	}

 	if (args->v0.huserd) {
 		userd = nvkm_umem_search(oclass->client, args->v0.huserd);
 		if (IS_ERR(userd)) {
 			ret = PTR_ERR(userd);
 			userd = NULL;
 			goto done;
 		}
 	}

 	/* Allocate channel. */
 	if (!(uchan = kzalloc(sizeof(*uchan), GFP_KERNEL))) {
 		ret = -ENOMEM;
 		goto done;
 	}

 	nvkm_object_ctor(&nvkm_uchan, oclass, &uchan->object);
 	*pobject = &uchan->object;

 	ret = nvkm_chan_new_(fifo->func->chan.func, runl, args->v0.runq, cgrp, args->v0.name,
 			     args->v0.priv != 0, args->v0.devm, vmm, ctxdma, args->v0.offset,
 			     args->v0.length, userd, args->v0.ouserd, &uchan->chan);
 	if (ret)
 		goto done;

 	chan = uchan->chan;

 	/* Return channel info to caller. */
 	if (chan->func->doorbell_handle)
 		args->v0.token = chan->func->doorbell_handle(chan);
 	else
 		args->v0.token = ~0;

 	args->v0.chid = chan->id;

 	switch (nvkm_memory_target(chan->inst->memory)) {
 	case NVKM_MEM_TARGET_INST: args->v0.aper = NVIF_CHAN_V0_INST_APER_INST; break;
 	case NVKM_MEM_TARGET_VRAM: args->v0.aper = NVIF_CHAN_V0_INST_APER_VRAM; break;
 	case NVKM_MEM_TARGET_HOST: args->v0.aper = NVIF_CHAN_V0_INST_APER_HOST; break;
 	case NVKM_MEM_TARGET_NCOH: args->v0.aper = NVIF_CHAN_V0_INST_APER_NCOH; break;
 	default:
 		WARN_ON(1);
 		ret = -EFAULT;
 		break;
 	}

 	args->v0.inst = nvkm_memory_addr(chan->inst->memory);
 done:
 	nvkm_memory_unref(&userd);
 	nvkm_vmm_unref(&vmm);
 	return ret;
 }
	/*
	* Copyright 2021 Red Hat 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
	*/
	#define nvkm_uchan(p) container_of((p), struct nvkm_uchan, object)
	#include "priv.h"
	#include "cgrp.h"
	#include "chan.h"
	#include "chid.h"
	#include "runl.h"

	#include <core/gpuobj.h>
	#include <core/oproxy.h>
	#include <subdev/mmu.h>
	#include <engine/dma.h>

	#include <nvif/if0020.h>

	struct nvkm_uchan {
	struct nvkm_object object;
	struct nvkm_chan *chan;
	};

	static int
	nvkm_uchan_uevent(struct nvkm_object object, void argv, u32 argc, struct nvkm_uevent *uevent)
	{
	struct nvkm_chan *chan = nvkm_uchan(object)->chan;
	struct nvkm_runl *runl = chan->cgrp->runl;
	union nvif_chan_event_args *args = argv;

	if (!uevent)
	return 0;
	if (argc != sizeof(args->v0) \|\| args->v0.version != 0)
	return -ENOSYS;

	switch (args->v0.type) {
	case NVIF_CHAN_EVENT_V0_NON_STALL_INTR:
	return nvkm_uevent_add(uevent, &runl->fifo->nonstall.event, runl->id,
	NVKM_FIFO_NONSTALL_EVENT, NULL);
	case NVIF_CHAN_EVENT_V0_KILLED:
	return nvkm_uevent_add(uevent, &runl->chid->event, chan->id,
	NVKM_CHAN_EVENT_ERRORED, NULL);
	default:
	break;
	}

	return -ENOSYS;
	}

	struct nvkm_uobj {
	struct nvkm_oproxy oproxy;
	struct nvkm_chan *chan;
	struct nvkm_cctx *cctx;
	int hash;
	};

	static int
	nvkm_uchan_object_fini_1(struct nvkm_oproxy *oproxy, bool suspend)
	{
	struct nvkm_uobj uobj = container_of(oproxy, typeof(uobj), oproxy);
	struct nvkm_chan *chan = uobj->chan;
	struct nvkm_cctx *cctx = uobj->cctx;
	struct nvkm_ectx *ectx = cctx->vctx->ectx;

	if (!ectx->object)
	return 0;

	/* Unbind engine context from channel, if no longer required. */
	if (refcount_dec_and_mutex_lock(&cctx->uses, &chan->cgrp->mutex)) {
	nvkm_chan_cctx_bind(chan, ectx->engn, NULL);

	if (refcount_dec_and_test(&ectx->uses))
	nvkm_object_fini(ectx->object, false);
	mutex_unlock(&chan->cgrp->mutex);
	}

	return 0;
	}

	static int
	nvkm_uchan_object_init_0(struct nvkm_oproxy *oproxy)
	{
	struct nvkm_uobj uobj = container_of(oproxy, typeof(uobj), oproxy);
	struct nvkm_chan *chan = uobj->chan;
	struct nvkm_cctx *cctx = uobj->cctx;
	struct nvkm_ectx *ectx = cctx->vctx->ectx;
	int ret = 0;

	if (!ectx->object)
	return 0;

	/* Bind engine context to channel, if it hasn't been already. */
	if (!refcount_inc_not_zero(&cctx->uses)) {
	mutex_lock(&chan->cgrp->mutex);
	if (!refcount_inc_not_zero(&cctx->uses)) {
	if (!refcount_inc_not_zero(&ectx->uses)) {
	ret = nvkm_object_init(ectx->object);
	if (ret == 0)
	refcount_set(&ectx->uses, 1);
	}

	if (ret == 0) {
	nvkm_chan_cctx_bind(chan, ectx->engn, cctx);
	refcount_set(&cctx->uses, 1);
	}
	}
	mutex_unlock(&chan->cgrp->mutex);
	}

	return ret;
	}

	static void
	nvkm_uchan_object_dtor(struct nvkm_oproxy *oproxy)
	{
	struct nvkm_uobj uobj = container_of(oproxy, typeof(uobj), oproxy);
	struct nvkm_engn *engn;

	if (!uobj->cctx)
	return;

	engn = uobj->cctx->vctx->ectx->engn;
	if (engn->func->ramht_del)
	engn->func->ramht_del(uobj->chan, uobj->hash);

	nvkm_chan_cctx_put(uobj->chan, &uobj->cctx);
	}

	static const struct nvkm_oproxy_func
	nvkm_uchan_object = {
	.dtor[1] = nvkm_uchan_object_dtor,
	.init[0] = nvkm_uchan_object_init_0,
	.fini[1] = nvkm_uchan_object_fini_1,
	};

	static int
	nvkm_uchan_object_new(const struct nvkm_oclass oclass, void argv, u32 argc,
	struct nvkm_object **pobject)
	{
	struct nvkm_chan *chan = nvkm_uchan(oclass->parent)->chan;
	struct nvkm_cgrp *cgrp = chan->cgrp;
	struct nvkm_engn *engn;
	struct nvkm_uobj *uobj;
	int ret;

	/* Lookup host engine state for target engine. */
	engn = nvkm_runl_find_engn(engn, cgrp->runl, engn->engine == oclass->engine);
	if (WARN_ON(!engn))
	return -EINVAL;

	/* Allocate SW object. */
	if (!(uobj = kzalloc(sizeof(*uobj), GFP_KERNEL)))
	return -ENOMEM;

	nvkm_oproxy_ctor(&nvkm_uchan_object, oclass, &uobj->oproxy);
	uobj->chan = chan;
	*pobject = &uobj->oproxy.base;

	/* Ref. channel context for target engine.*/
	ret = nvkm_chan_cctx_get(chan, engn, &uobj->cctx, oclass->client);
	if (ret)
	return ret;

	/* Allocate HW object. */
	ret = oclass->base.ctor(&(const struct nvkm_oclass) {
	.base = oclass->base,
	.engn = oclass->engn,
	.handle = oclass->handle,
	.object = oclass->object,
	.client = oclass->client,
	.parent = uobj->cctx->vctx->ectx->object ?: oclass->parent,
	.engine = engn->engine,
	}, argv, argc, &uobj->oproxy.object);
	if (ret)
	return ret;

	if (engn->func->ramht_add) {
	uobj->hash = engn->func->ramht_add(engn, uobj->oproxy.object, uobj->chan);
	if (uobj->hash < 0)
	return uobj->hash;
	}

	return 0;
	}

	static int
	nvkm_uchan_sclass(struct nvkm_object object, int index, struct nvkm_oclass oclass)
	{
	struct nvkm_chan *chan = nvkm_uchan(object)->chan;
	struct nvkm_engn *engn;
	int ret, runq = 0;

	nvkm_runl_foreach_engn(engn, chan->cgrp->runl) {
	struct nvkm_engine *engine = engn->engine;
	int c = 0;

	/* Each runqueue, on runlists with multiple, has its own LCE. */
	if (engn->runl->func->runqs) {
	if (engine->subdev.type == NVKM_ENGINE_CE) {
	if (chan->runq != runq++)
	continue;
	}
	}

	oclass->engine = engine;
	oclass->base.oclass = 0;

	if (engine->func->fifo.sclass) {
	ret = engine->func->fifo.sclass(oclass, index);
	if (oclass->base.oclass) {
	if (!oclass->base.ctor)
	oclass->base.ctor = nvkm_object_new;
	oclass->ctor = nvkm_uchan_object_new;
	return 0;
	}

	index -= ret;
	continue;
	}

	while (engine->func->sclass[c].oclass) {
	if (c++ == index) {
	oclass->base = engine->func->sclass[index];
	if (!oclass->base.ctor)
	oclass->base.ctor = nvkm_object_new;
	oclass->ctor = nvkm_uchan_object_new;
	return 0;
	}
	}

	index -= c;
	}

	return -EINVAL;
	}

	static int
	nvkm_uchan_map(struct nvkm_object object, void argv, u32 argc,
	enum nvkm_object_map type, u64 addr, u64 *size)
	{
	struct nvkm_chan *chan = nvkm_uchan(object)->chan;
	struct nvkm_device *device = chan->cgrp->runl->fifo->engine.subdev.device;

	if (chan->func->userd->bar < 0)
	return -ENOSYS;

	*type = NVKM_OBJECT_MAP_IO;
	*addr = device->func->resource_addr(device, chan->func->userd->bar) +
	chan->func->userd->base + chan->userd.base;
	*size = chan->func->userd->size;
	return 0;
	}

	static int
	nvkm_uchan_fini(struct nvkm_object *object, bool suspend)
	{
	struct nvkm_chan *chan = nvkm_uchan(object)->chan;

	nvkm_chan_block(chan);
	nvkm_chan_remove(chan, true);

	if (chan->func->unbind)
	chan->func->unbind(chan);

	return 0;
	}

	static int
	nvkm_uchan_init(struct nvkm_object *object)
	{
	struct nvkm_chan *chan = nvkm_uchan(object)->chan;

	if (atomic_read(&chan->errored))
	return 0;

	if (chan->func->bind)
	chan->func->bind(chan);

	nvkm_chan_allow(chan);
	nvkm_chan_insert(chan);
	return 0;
	}

	static void *
	nvkm_uchan_dtor(struct nvkm_object *object)
	{
	struct nvkm_uchan *uchan = nvkm_uchan(object);

	nvkm_chan_del(&uchan->chan);
	return uchan;
	}

	static const struct nvkm_object_func
	nvkm_uchan = {
	.dtor = nvkm_uchan_dtor,
	.init = nvkm_uchan_init,
	.fini = nvkm_uchan_fini,
	.map = nvkm_uchan_map,
	.sclass = nvkm_uchan_sclass,
	.uevent = nvkm_uchan_uevent,
	};

	struct nvkm_chan *
	nvkm_uchan_chan(struct nvkm_object *object)
	{
	if (WARN_ON(object->func != &nvkm_uchan))
	return NULL;

	return nvkm_uchan(object)->chan;
	}

	int
	nvkm_uchan_new(struct nvkm_fifo fifo, struct nvkm_cgrp cgrp, const struct nvkm_oclass *oclass,
	void argv, u32 argc, struct nvkm_object *pobject)
	{
	union nvif_chan_args *args = argv;
	struct nvkm_runl *runl;
	struct nvkm_vmm *vmm = NULL;
	struct nvkm_dmaobj *ctxdma = NULL;
	struct nvkm_memory *userd = NULL;
	struct nvkm_uchan *uchan;
	struct nvkm_chan *chan;
	int ret;

	if (argc < sizeof(args->v0) \|\| args->v0.version != 0)
	return -ENOSYS;
	argc -= sizeof(args->v0);

	if (args->v0.namelen != argc)
	return -EINVAL;

	/* Lookup objects referenced in args. */
	runl = nvkm_runl_get(fifo, args->v0.runlist, 0);
	if (!runl)
	return -EINVAL;

	if (args->v0.vmm) {
	vmm = nvkm_uvmm_search(oclass->client, args->v0.vmm);
	if (IS_ERR(vmm))
	return PTR_ERR(vmm);
	}

	if (args->v0.ctxdma) {
	ctxdma = nvkm_dmaobj_search(oclass->client, args->v0.ctxdma);
	if (IS_ERR(ctxdma)) {
	ret = PTR_ERR(ctxdma);
	goto done;
	}
	}

	if (args->v0.huserd) {
	userd = nvkm_umem_search(oclass->client, args->v0.huserd);
	if (IS_ERR(userd)) {
	ret = PTR_ERR(userd);
	userd = NULL;
	goto done;
	}
	}

	/* Allocate channel. */
	if (!(uchan = kzalloc(sizeof(*uchan), GFP_KERNEL))) {
	ret = -ENOMEM;
	goto done;
	}

	nvkm_object_ctor(&nvkm_uchan, oclass, &uchan->object);
	*pobject = &uchan->object;

	ret = nvkm_chan_new_(fifo->func->chan.func, runl, args->v0.runq, cgrp, args->v0.name,
	args->v0.priv != 0, args->v0.devm, vmm, ctxdma, args->v0.offset,
	args->v0.length, userd, args->v0.ouserd, &uchan->chan);
	if (ret)
	goto done;

	chan = uchan->chan;

	/* Return channel info to caller. */
	if (chan->func->doorbell_handle)
	args->v0.token = chan->func->doorbell_handle(chan);
	else
	args->v0.token = ~0;

	args->v0.chid = chan->id;

	switch (nvkm_memory_target(chan->inst->memory)) {
	case NVKM_MEM_TARGET_INST: args->v0.aper = NVIF_CHAN_V0_INST_APER_INST; break;
	case NVKM_MEM_TARGET_VRAM: args->v0.aper = NVIF_CHAN_V0_INST_APER_VRAM; break;
	case NVKM_MEM_TARGET_HOST: args->v0.aper = NVIF_CHAN_V0_INST_APER_HOST; break;
	case NVKM_MEM_TARGET_NCOH: args->v0.aper = NVIF_CHAN_V0_INST_APER_NCOH; break;
	default:
	WARN_ON(1);
	ret = -EFAULT;
	break;
	}

	args->v0.inst = nvkm_memory_addr(chan->inst->memory);
	done:
	nvkm_memory_unref(&userd);
	nvkm_vmm_unref(&vmm);
	return ret;
	}