drivers/gpu/drm/nouveau/nvkm/subdev/mmu/base.c - pub/scm/linux/kernel/git/kgene/linux-samsung - Git at Google

 /*
  * Copyright 2010 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.
  *
  * Authors: Ben Skeggs
  */
 #include "priv.h"

 #include <core/gpuobj.h>
 #include <subdev/fb.h>

 void
 nvkm_vm_map_at(struct nvkm_vma *vma, u64 delta, struct nvkm_mem *node)
 {
 	struct nvkm_vm *vm = vma->vm;
 	struct nvkm_mmu *mmu = vm->mmu;
 	struct nvkm_mm_node *r = node->mem;
 	int big = vma->node->type != mmu->func->spg_shift;
 	u32 offset = vma->node->offset + (delta >> 12);
 	u32 bits = vma->node->type - 12;
 	u32 pde  = (offset >> mmu->func->pgt_bits) - vm->fpde;
 	u32 pte  = (offset & ((1 << mmu->func->pgt_bits) - 1)) >> bits;
 	u32 max  = 1 << (mmu->func->pgt_bits - bits);
 	u32 end, len;

 	delta = 0;
 	while (r) {
 		u64 phys = (u64)r->offset << 12;
 		u32 num  = r->length >> bits;

 		while (num) {
 			struct nvkm_memory *pgt = vm->pgt[pde].mem[big];

 			end = (pte + num);
 			if (unlikely(end >= max))
 				end = max;
 			len = end - pte;

 			mmu->func->map(vma, pgt, node, pte, len, phys, delta);

 			num -= len;
 			pte += len;
 			if (unlikely(end >= max)) {
 				phys += len << (bits + 12);
 				pde++;
 				pte = 0;
 			}

 			delta += (u64)len << vma->node->type;
 		}
 		r = r->next;
 	};

 	mmu->func->flush(vm);
 }

 static void
 nvkm_vm_map_sg_table(struct nvkm_vma *vma, u64 delta, u64 length,
 		     struct nvkm_mem *mem)
 {
 	struct nvkm_vm *vm = vma->vm;
 	struct nvkm_mmu *mmu = vm->mmu;
 	int big = vma->node->type != mmu->func->spg_shift;
 	u32 offset = vma->node->offset + (delta >> 12);
 	u32 bits = vma->node->type - 12;
 	u32 num  = length >> vma->node->type;
 	u32 pde  = (offset >> mmu->func->pgt_bits) - vm->fpde;
 	u32 pte  = (offset & ((1 << mmu->func->pgt_bits) - 1)) >> bits;
 	u32 max  = 1 << (mmu->func->pgt_bits - bits);
 	unsigned m, sglen;
 	u32 end, len;
 	int i;
 	struct scatterlist *sg;

 	for_each_sg(mem->sg->sgl, sg, mem->sg->nents, i) {
 		struct nvkm_memory *pgt = vm->pgt[pde].mem[big];
 		sglen = sg_dma_len(sg) >> PAGE_SHIFT;

 		end = pte + sglen;
 		if (unlikely(end >= max))
 			end = max;
 		len = end - pte;

 		for (m = 0; m < len; m++) {
 			dma_addr_t addr = sg_dma_address(sg) + (m << PAGE_SHIFT);

 			mmu->func->map_sg(vma, pgt, mem, pte, 1, &addr);
 			num--;
 			pte++;

 			if (num == 0)
 				goto finish;
 		}
 		if (unlikely(end >= max)) {
 			pde++;
 			pte = 0;
 		}
 		if (m < sglen) {
 			for (; m < sglen; m++) {
 				dma_addr_t addr = sg_dma_address(sg) + (m << PAGE_SHIFT);

 				mmu->func->map_sg(vma, pgt, mem, pte, 1, &addr);
 				num--;
 				pte++;
 				if (num == 0)
 					goto finish;
 			}
 		}

 	}
 finish:
 	mmu->func->flush(vm);
 }

 static void
 nvkm_vm_map_sg(struct nvkm_vma *vma, u64 delta, u64 length,
 	       struct nvkm_mem *mem)
 {
 	struct nvkm_vm *vm = vma->vm;
 	struct nvkm_mmu *mmu = vm->mmu;
 	dma_addr_t *list = mem->pages;
 	int big = vma->node->type != mmu->func->spg_shift;
 	u32 offset = vma->node->offset + (delta >> 12);
 	u32 bits = vma->node->type - 12;
 	u32 num  = length >> vma->node->type;
 	u32 pde  = (offset >> mmu->func->pgt_bits) - vm->fpde;
 	u32 pte  = (offset & ((1 << mmu->func->pgt_bits) - 1)) >> bits;
 	u32 max  = 1 << (mmu->func->pgt_bits - bits);
 	u32 end, len;

 	while (num) {
 		struct nvkm_memory *pgt = vm->pgt[pde].mem[big];

 		end = (pte + num);
 		if (unlikely(end >= max))
 			end = max;
 		len = end - pte;

 		mmu->func->map_sg(vma, pgt, mem, pte, len, list);

 		num  -= len;
 		pte  += len;
 		list += len;
 		if (unlikely(end >= max)) {
 			pde++;
 			pte = 0;
 		}
 	}

 	mmu->func->flush(vm);
 }

 void
 nvkm_vm_map(struct nvkm_vma *vma, struct nvkm_mem *node)
 {
 	if (node->sg)
 		nvkm_vm_map_sg_table(vma, 0, node->size << 12, node);
 	else
 	if (node->pages)
 		nvkm_vm_map_sg(vma, 0, node->size << 12, node);
 	else
 		nvkm_vm_map_at(vma, 0, node);
 }

 void
 nvkm_vm_unmap_at(struct nvkm_vma *vma, u64 delta, u64 length)
 {
 	struct nvkm_vm *vm = vma->vm;
 	struct nvkm_mmu *mmu = vm->mmu;
 	int big = vma->node->type != mmu->func->spg_shift;
 	u32 offset = vma->node->offset + (delta >> 12);
 	u32 bits = vma->node->type - 12;
 	u32 num  = length >> vma->node->type;
 	u32 pde  = (offset >> mmu->func->pgt_bits) - vm->fpde;
 	u32 pte  = (offset & ((1 << mmu->func->pgt_bits) - 1)) >> bits;
 	u32 max  = 1 << (mmu->func->pgt_bits - bits);
 	u32 end, len;

 	while (num) {
 		struct nvkm_memory *pgt = vm->pgt[pde].mem[big];

 		end = (pte + num);
 		if (unlikely(end >= max))
 			end = max;
 		len = end - pte;

 		mmu->func->unmap(vma, pgt, pte, len);

 		num -= len;
 		pte += len;
 		if (unlikely(end >= max)) {
 			pde++;
 			pte = 0;
 		}
 	}

 	mmu->func->flush(vm);
 }

 void
 nvkm_vm_unmap(struct nvkm_vma *vma)
 {
 	nvkm_vm_unmap_at(vma, 0, (u64)vma->node->length << 12);
 }

 static void
 nvkm_vm_unmap_pgt(struct nvkm_vm *vm, int big, u32 fpde, u32 lpde)
 {
 	struct nvkm_mmu *mmu = vm->mmu;
 	struct nvkm_vm_pgd *vpgd;
 	struct nvkm_vm_pgt *vpgt;
 	struct nvkm_memory *pgt;
 	u32 pde;

 	for (pde = fpde; pde <= lpde; pde++) {
 		vpgt = &vm->pgt[pde - vm->fpde];
 		if (--vpgt->refcount[big])
 			continue;

 		pgt = vpgt->mem[big];
 		vpgt->mem[big] = NULL;

 		list_for_each_entry(vpgd, &vm->pgd_list, head) {
 			mmu->func->map_pgt(vpgd->obj, pde, vpgt->mem);
 		}

 		nvkm_memory_del(&pgt);
 	}
 }

 static int
 nvkm_vm_map_pgt(struct nvkm_vm *vm, u32 pde, u32 type)
 {
 	struct nvkm_mmu *mmu = vm->mmu;
 	struct nvkm_vm_pgt *vpgt = &vm->pgt[pde - vm->fpde];
 	struct nvkm_vm_pgd *vpgd;
 	int big = (type != mmu->func->spg_shift);
 	u32 pgt_size;
 	int ret;

 	pgt_size  = (1 << (mmu->func->pgt_bits + 12)) >> type;
 	pgt_size *= 8;

 	ret = nvkm_memory_new(mmu->subdev.device, NVKM_MEM_TARGET_INST,
 			      pgt_size, 0x1000, true, &vpgt->mem[big]);
 	if (unlikely(ret))
 		return ret;

 	list_for_each_entry(vpgd, &vm->pgd_list, head) {
 		mmu->func->map_pgt(vpgd->obj, pde, vpgt->mem);
 	}

 	vpgt->refcount[big]++;
 	return 0;
 }

 int
 nvkm_vm_get(struct nvkm_vm *vm, u64 size, u32 page_shift, u32 access,
 	    struct nvkm_vma *vma)
 {
 	struct nvkm_mmu *mmu = vm->mmu;
 	u32 align = (1 << page_shift) >> 12;
 	u32 msize = size >> 12;
 	u32 fpde, lpde, pde;
 	int ret;

 	mutex_lock(&vm->mutex);
 	ret = nvkm_mm_head(&vm->mm, 0, page_shift, msize, msize, align,
 			   &vma->node);
 	if (unlikely(ret != 0)) {
 		mutex_unlock(&vm->mutex);
 		return ret;
 	}

 	fpde = (vma->node->offset >> mmu->func->pgt_bits);
 	lpde = (vma->node->offset + vma->node->length - 1) >> mmu->func->pgt_bits;

 	for (pde = fpde; pde <= lpde; pde++) {
 		struct nvkm_vm_pgt *vpgt = &vm->pgt[pde - vm->fpde];
 		int big = (vma->node->type != mmu->func->spg_shift);

 		if (likely(vpgt->refcount[big])) {
 			vpgt->refcount[big]++;
 			continue;
 		}

 		ret = nvkm_vm_map_pgt(vm, pde, vma->node->type);
 		if (ret) {
 			if (pde != fpde)
 				nvkm_vm_unmap_pgt(vm, big, fpde, pde - 1);
 			nvkm_mm_free(&vm->mm, &vma->node);
 			mutex_unlock(&vm->mutex);
 			return ret;
 		}
 	}
 	mutex_unlock(&vm->mutex);

 	vma->vm = NULL;
 	nvkm_vm_ref(vm, &vma->vm, NULL);
 	vma->offset = (u64)vma->node->offset << 12;
 	vma->access = access;
 	return 0;
 }

 void
 nvkm_vm_put(struct nvkm_vma *vma)
 {
 	struct nvkm_mmu *mmu;
 	struct nvkm_vm *vm;
 	u32 fpde, lpde;

 	if (unlikely(vma->node == NULL))
 		return;
 	vm = vma->vm;
 	mmu = vm->mmu;

 	fpde = (vma->node->offset >> mmu->func->pgt_bits);
 	lpde = (vma->node->offset + vma->node->length - 1) >> mmu->func->pgt_bits;

 	mutex_lock(&vm->mutex);
 	nvkm_vm_unmap_pgt(vm, vma->node->type != mmu->func->spg_shift, fpde, lpde);
 	nvkm_mm_free(&vm->mm, &vma->node);
 	mutex_unlock(&vm->mutex);

 	nvkm_vm_ref(NULL, &vma->vm, NULL);
 }

 int
 nvkm_vm_boot(struct nvkm_vm *vm, u64 size)
 {
 	struct nvkm_mmu *mmu = vm->mmu;
 	struct nvkm_memory *pgt;
 	int ret;

 	ret = nvkm_memory_new(mmu->subdev.device, NVKM_MEM_TARGET_INST,
 			      (size >> mmu->func->spg_shift) * 8, 0x1000, true, &pgt);
 	if (ret == 0) {
 		vm->pgt[0].refcount[0] = 1;
 		vm->pgt[0].mem[0] = pgt;
 		nvkm_memory_boot(pgt, vm);
 	}

 	return ret;
 }

 int
 nvkm_vm_create(struct nvkm_mmu *mmu, u64 offset, u64 length, u64 mm_offset,
 	       u32 block, struct lock_class_key *key, struct nvkm_vm **pvm)
 {
 	static struct lock_class_key _key;
 	struct nvkm_vm *vm;
 	u64 mm_length = (offset + length) - mm_offset;
 	int ret;

 	vm = kzalloc(sizeof(*vm), GFP_KERNEL);
 	if (!vm)
 		return -ENOMEM;

 	__mutex_init(&vm->mutex, "&vm->mutex", key ? key : &_key);
 	INIT_LIST_HEAD(&vm->pgd_list);
 	vm->mmu = mmu;
 	kref_init(&vm->refcount);
 	vm->fpde = offset >> (mmu->func->pgt_bits + 12);
 	vm->lpde = (offset + length - 1) >> (mmu->func->pgt_bits + 12);

 	vm->pgt  = vzalloc((vm->lpde - vm->fpde + 1) * sizeof(*vm->pgt));
 	if (!vm->pgt) {
 		kfree(vm);
 		return -ENOMEM;
 	}

 	ret = nvkm_mm_init(&vm->mm, mm_offset >> 12, mm_length >> 12,
 			   block >> 12);
 	if (ret) {
 		vfree(vm->pgt);
 		kfree(vm);
 		return ret;
 	}

 	*pvm = vm;

 	return 0;
 }

 int
 nvkm_vm_new(struct nvkm_device *device, u64 offset, u64 length, u64 mm_offset,
 	    struct lock_class_key *key, struct nvkm_vm **pvm)
 {
 	struct nvkm_mmu *mmu = device->mmu;
 	if (!mmu->func->create)
 		return -EINVAL;
 	return mmu->func->create(mmu, offset, length, mm_offset, key, pvm);
 }

 static int
 nvkm_vm_link(struct nvkm_vm *vm, struct nvkm_gpuobj *pgd)
 {
 	struct nvkm_mmu *mmu = vm->mmu;
 	struct nvkm_vm_pgd *vpgd;
 	int i;

 	if (!pgd)
 		return 0;

 	vpgd = kzalloc(sizeof(*vpgd), GFP_KERNEL);
 	if (!vpgd)
 		return -ENOMEM;

 	vpgd->obj = pgd;

 	mutex_lock(&vm->mutex);
 	for (i = vm->fpde; i <= vm->lpde; i++)
 		mmu->func->map_pgt(pgd, i, vm->pgt[i - vm->fpde].mem);
 	list_add(&vpgd->head, &vm->pgd_list);
 	mutex_unlock(&vm->mutex);
 	return 0;
 }

 static void
 nvkm_vm_unlink(struct nvkm_vm *vm, struct nvkm_gpuobj *mpgd)
 {
 	struct nvkm_vm_pgd *vpgd, *tmp;

 	if (!mpgd)
 		return;

 	mutex_lock(&vm->mutex);
 	list_for_each_entry_safe(vpgd, tmp, &vm->pgd_list, head) {
 		if (vpgd->obj == mpgd) {
 			list_del(&vpgd->head);
 			kfree(vpgd);
 			break;
 		}
 	}
 	mutex_unlock(&vm->mutex);
 }

 static void
 nvkm_vm_del(struct kref *kref)
 {
 	struct nvkm_vm *vm = container_of(kref, typeof(*vm), refcount);
 	struct nvkm_vm_pgd *vpgd, *tmp;

 	list_for_each_entry_safe(vpgd, tmp, &vm->pgd_list, head) {
 		nvkm_vm_unlink(vm, vpgd->obj);
 	}

 	nvkm_mm_fini(&vm->mm);
 	vfree(vm->pgt);
 	kfree(vm);
 }

 int
 nvkm_vm_ref(struct nvkm_vm *ref, struct nvkm_vm **ptr, struct nvkm_gpuobj *pgd)
 {
 	if (ref) {
 		int ret = nvkm_vm_link(ref, pgd);
 		if (ret)
 			return ret;

 		kref_get(&ref->refcount);
 	}

 	if (*ptr) {
 		nvkm_vm_unlink(*ptr, pgd);
 		kref_put(&(*ptr)->refcount, nvkm_vm_del);
 	}

 	*ptr = ref;
 	return 0;
 }

 static int
 nvkm_mmu_oneinit(struct nvkm_subdev *subdev)
 {
 	struct nvkm_mmu *mmu = nvkm_mmu(subdev);
 	if (mmu->func->oneinit)
 		return mmu->func->oneinit(mmu);
 	return 0;
 }

 static int
 nvkm_mmu_init(struct nvkm_subdev *subdev)
 {
 	struct nvkm_mmu *mmu = nvkm_mmu(subdev);
 	if (mmu->func->init)
 		mmu->func->init(mmu);
 	return 0;
 }

 static void *
 nvkm_mmu_dtor(struct nvkm_subdev *subdev)
 {
 	struct nvkm_mmu *mmu = nvkm_mmu(subdev);
 	if (mmu->func->dtor)
 		return mmu->func->dtor(mmu);
 	return mmu;
 }

 static const struct nvkm_subdev_func
 nvkm_mmu = {
 	.dtor = nvkm_mmu_dtor,
 	.oneinit = nvkm_mmu_oneinit,
 	.init = nvkm_mmu_init,
 };

 void
 nvkm_mmu_ctor(const struct nvkm_mmu_func *func, struct nvkm_device *device,
 	      int index, struct nvkm_mmu *mmu)
 {
 	nvkm_subdev_ctor(&nvkm_mmu, device, index, &mmu->subdev);
 	mmu->func = func;
 	mmu->limit = func->limit;
 	mmu->dma_bits = func->dma_bits;
 	mmu->lpg_shift = func->lpg_shift;
 }

 int
 nvkm_mmu_new_(const struct nvkm_mmu_func *func, struct nvkm_device *device,
 	      int index, struct nvkm_mmu **pmmu)
 {
 	if (!(*pmmu = kzalloc(sizeof(**pmmu), GFP_KERNEL)))
 		return -ENOMEM;
 	nvkm_mmu_ctor(func, device, index, *pmmu);
 	return 0;
 }
	/*
	* Copyright 2010 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.
	*
	* Authors: Ben Skeggs
	*/
	#include "priv.h"

	#include <core/gpuobj.h>
	#include <subdev/fb.h>

	void
	nvkm_vm_map_at(struct nvkm_vma vma, u64 delta, struct nvkm_mem node)
	{
	struct nvkm_vm *vm = vma->vm;
	struct nvkm_mmu *mmu = vm->mmu;
	struct nvkm_mm_node *r = node->mem;
	int big = vma->node->type != mmu->func->spg_shift;
	u32 offset = vma->node->offset + (delta >> 12);
	u32 bits = vma->node->type - 12;
	u32 pde = (offset >> mmu->func->pgt_bits) - vm->fpde;
	u32 pte = (offset & ((1 << mmu->func->pgt_bits) - 1)) >> bits;
	u32 max = 1 << (mmu->func->pgt_bits - bits);
	u32 end, len;

	delta = 0;
	while (r) {
	u64 phys = (u64)r->offset << 12;
	u32 num = r->length >> bits;

	while (num) {
	struct nvkm_memory *pgt = vm->pgt[pde].mem[big];

	end = (pte + num);
	if (unlikely(end >= max))
	end = max;
	len = end - pte;

	mmu->func->map(vma, pgt, node, pte, len, phys, delta);

	num -= len;
	pte += len;
	if (unlikely(end >= max)) {
	phys += len << (bits + 12);
	pde++;
	pte = 0;
	}

	delta += (u64)len << vma->node->type;
	}
	r = r->next;
	};

	mmu->func->flush(vm);
	}

	static void
	nvkm_vm_map_sg_table(struct nvkm_vma *vma, u64 delta, u64 length,
	struct nvkm_mem *mem)
	{
	struct nvkm_vm *vm = vma->vm;
	struct nvkm_mmu *mmu = vm->mmu;
	int big = vma->node->type != mmu->func->spg_shift;
	u32 offset = vma->node->offset + (delta >> 12);
	u32 bits = vma->node->type - 12;
	u32 num = length >> vma->node->type;
	u32 pde = (offset >> mmu->func->pgt_bits) - vm->fpde;
	u32 pte = (offset & ((1 << mmu->func->pgt_bits) - 1)) >> bits;
	u32 max = 1 << (mmu->func->pgt_bits - bits);
	unsigned m, sglen;
	u32 end, len;
	int i;
	struct scatterlist *sg;

	for_each_sg(mem->sg->sgl, sg, mem->sg->nents, i) {
	struct nvkm_memory *pgt = vm->pgt[pde].mem[big];
	sglen = sg_dma_len(sg) >> PAGE_SHIFT;

	end = pte + sglen;
	if (unlikely(end >= max))
	end = max;
	len = end - pte;

	for (m = 0; m < len; m++) {
	dma_addr_t addr = sg_dma_address(sg) + (m << PAGE_SHIFT);

	mmu->func->map_sg(vma, pgt, mem, pte, 1, &addr);
	num--;
	pte++;

	if (num == 0)
	goto finish;
	}
	if (unlikely(end >= max)) {
	pde++;
	pte = 0;
	}
	if (m < sglen) {
	for (; m < sglen; m++) {
	dma_addr_t addr = sg_dma_address(sg) + (m << PAGE_SHIFT);

	mmu->func->map_sg(vma, pgt, mem, pte, 1, &addr);
	num--;
	pte++;
	if (num == 0)
	goto finish;
	}
	}

	}
	finish:
	mmu->func->flush(vm);
	}

	static void
	nvkm_vm_map_sg(struct nvkm_vma *vma, u64 delta, u64 length,
	struct nvkm_mem *mem)
	{
	struct nvkm_vm *vm = vma->vm;
	struct nvkm_mmu *mmu = vm->mmu;
	dma_addr_t *list = mem->pages;
	int big = vma->node->type != mmu->func->spg_shift;
	u32 offset = vma->node->offset + (delta >> 12);
	u32 bits = vma->node->type - 12;
	u32 num = length >> vma->node->type;
	u32 pde = (offset >> mmu->func->pgt_bits) - vm->fpde;
	u32 pte = (offset & ((1 << mmu->func->pgt_bits) - 1)) >> bits;
	u32 max = 1 << (mmu->func->pgt_bits - bits);
	u32 end, len;

	while (num) {
	struct nvkm_memory *pgt = vm->pgt[pde].mem[big];

	end = (pte + num);
	if (unlikely(end >= max))
	end = max;
	len = end - pte;

	mmu->func->map_sg(vma, pgt, mem, pte, len, list);

	num -= len;
	pte += len;
	list += len;
	if (unlikely(end >= max)) {
	pde++;
	pte = 0;
	}
	}

	mmu->func->flush(vm);
	}

	void
	nvkm_vm_map(struct nvkm_vma vma, struct nvkm_mem node)
	{
	if (node->sg)
	nvkm_vm_map_sg_table(vma, 0, node->size << 12, node);
	else
	if (node->pages)
	nvkm_vm_map_sg(vma, 0, node->size << 12, node);
	else
	nvkm_vm_map_at(vma, 0, node);
	}

	void
	nvkm_vm_unmap_at(struct nvkm_vma *vma, u64 delta, u64 length)
	{
	struct nvkm_vm *vm = vma->vm;
	struct nvkm_mmu *mmu = vm->mmu;
	int big = vma->node->type != mmu->func->spg_shift;
	u32 offset = vma->node->offset + (delta >> 12);
	u32 bits = vma->node->type - 12;
	u32 num = length >> vma->node->type;
	u32 pde = (offset >> mmu->func->pgt_bits) - vm->fpde;
	u32 pte = (offset & ((1 << mmu->func->pgt_bits) - 1)) >> bits;
	u32 max = 1 << (mmu->func->pgt_bits - bits);
	u32 end, len;

	while (num) {
	struct nvkm_memory *pgt = vm->pgt[pde].mem[big];

	end = (pte + num);
	if (unlikely(end >= max))
	end = max;
	len = end - pte;

	mmu->func->unmap(vma, pgt, pte, len);

	num -= len;
	pte += len;
	if (unlikely(end >= max)) {
	pde++;
	pte = 0;
	}
	}

	mmu->func->flush(vm);
	}

	void
	nvkm_vm_unmap(struct nvkm_vma *vma)
	{
	nvkm_vm_unmap_at(vma, 0, (u64)vma->node->length << 12);
	}

	static void
	nvkm_vm_unmap_pgt(struct nvkm_vm *vm, int big, u32 fpde, u32 lpde)
	{
	struct nvkm_mmu *mmu = vm->mmu;
	struct nvkm_vm_pgd *vpgd;
	struct nvkm_vm_pgt *vpgt;
	struct nvkm_memory *pgt;
	u32 pde;

	for (pde = fpde; pde <= lpde; pde++) {
	vpgt = &vm->pgt[pde - vm->fpde];
	if (--vpgt->refcount[big])
	continue;

	pgt = vpgt->mem[big];
	vpgt->mem[big] = NULL;

	list_for_each_entry(vpgd, &vm->pgd_list, head) {
	mmu->func->map_pgt(vpgd->obj, pde, vpgt->mem);
	}

	nvkm_memory_del(&pgt);
	}
	}

	static int
	nvkm_vm_map_pgt(struct nvkm_vm *vm, u32 pde, u32 type)
	{
	struct nvkm_mmu *mmu = vm->mmu;
	struct nvkm_vm_pgt *vpgt = &vm->pgt[pde - vm->fpde];
	struct nvkm_vm_pgd *vpgd;
	int big = (type != mmu->func->spg_shift);
	u32 pgt_size;
	int ret;

	pgt_size = (1 << (mmu->func->pgt_bits + 12)) >> type;
	pgt_size *= 8;

	ret = nvkm_memory_new(mmu->subdev.device, NVKM_MEM_TARGET_INST,
	pgt_size, 0x1000, true, &vpgt->mem[big]);
	if (unlikely(ret))
	return ret;

	list_for_each_entry(vpgd, &vm->pgd_list, head) {
	mmu->func->map_pgt(vpgd->obj, pde, vpgt->mem);
	}

	vpgt->refcount[big]++;
	return 0;
	}

	int
	nvkm_vm_get(struct nvkm_vm *vm, u64 size, u32 page_shift, u32 access,
	struct nvkm_vma *vma)
	{
	struct nvkm_mmu *mmu = vm->mmu;
	u32 align = (1 << page_shift) >> 12;
	u32 msize = size >> 12;
	u32 fpde, lpde, pde;
	int ret;

	mutex_lock(&vm->mutex);
	ret = nvkm_mm_head(&vm->mm, 0, page_shift, msize, msize, align,
	&vma->node);
	if (unlikely(ret != 0)) {
	mutex_unlock(&vm->mutex);
	return ret;
	}

	fpde = (vma->node->offset >> mmu->func->pgt_bits);
	lpde = (vma->node->offset + vma->node->length - 1) >> mmu->func->pgt_bits;

	for (pde = fpde; pde <= lpde; pde++) {
	struct nvkm_vm_pgt *vpgt = &vm->pgt[pde - vm->fpde];
	int big = (vma->node->type != mmu->func->spg_shift);

	if (likely(vpgt->refcount[big])) {
	vpgt->refcount[big]++;
	continue;
	}

	ret = nvkm_vm_map_pgt(vm, pde, vma->node->type);
	if (ret) {
	if (pde != fpde)
	nvkm_vm_unmap_pgt(vm, big, fpde, pde - 1);
	nvkm_mm_free(&vm->mm, &vma->node);
	mutex_unlock(&vm->mutex);
	return ret;
	}
	}
	mutex_unlock(&vm->mutex);

	vma->vm = NULL;
	nvkm_vm_ref(vm, &vma->vm, NULL);
	vma->offset = (u64)vma->node->offset << 12;
	vma->access = access;
	return 0;
	}

	void
	nvkm_vm_put(struct nvkm_vma *vma)
	{
	struct nvkm_mmu *mmu;
	struct nvkm_vm *vm;
	u32 fpde, lpde;

	if (unlikely(vma->node == NULL))
	return;
	vm = vma->vm;
	mmu = vm->mmu;

	fpde = (vma->node->offset >> mmu->func->pgt_bits);
	lpde = (vma->node->offset + vma->node->length - 1) >> mmu->func->pgt_bits;

	mutex_lock(&vm->mutex);
	nvkm_vm_unmap_pgt(vm, vma->node->type != mmu->func->spg_shift, fpde, lpde);
	nvkm_mm_free(&vm->mm, &vma->node);
	mutex_unlock(&vm->mutex);

	nvkm_vm_ref(NULL, &vma->vm, NULL);
	}

	int
	nvkm_vm_boot(struct nvkm_vm *vm, u64 size)
	{
	struct nvkm_mmu *mmu = vm->mmu;
	struct nvkm_memory *pgt;
	int ret;

	ret = nvkm_memory_new(mmu->subdev.device, NVKM_MEM_TARGET_INST,
	(size >> mmu->func->spg_shift) * 8, 0x1000, true, &pgt);
	if (ret == 0) {
	vm->pgt[0].refcount[0] = 1;
	vm->pgt[0].mem[0] = pgt;
	nvkm_memory_boot(pgt, vm);
	}

	return ret;
	}

	int
	nvkm_vm_create(struct nvkm_mmu *mmu, u64 offset, u64 length, u64 mm_offset,
	u32 block, struct lock_class_key key, struct nvkm_vm *pvm)
	{
	static struct lock_class_key _key;
	struct nvkm_vm *vm;
	u64 mm_length = (offset + length) - mm_offset;
	int ret;

	vm = kzalloc(sizeof(*vm), GFP_KERNEL);
	if (!vm)
	return -ENOMEM;

	__mutex_init(&vm->mutex, "&vm->mutex", key ? key : &_key);
	INIT_LIST_HEAD(&vm->pgd_list);
	vm->mmu = mmu;
	kref_init(&vm->refcount);
	vm->fpde = offset >> (mmu->func->pgt_bits + 12);
	vm->lpde = (offset + length - 1) >> (mmu->func->pgt_bits + 12);

	vm->pgt = vzalloc((vm->lpde - vm->fpde + 1) * sizeof(*vm->pgt));
	if (!vm->pgt) {
	kfree(vm);
	return -ENOMEM;
	}

	ret = nvkm_mm_init(&vm->mm, mm_offset >> 12, mm_length >> 12,
	block >> 12);
	if (ret) {
	vfree(vm->pgt);
	kfree(vm);
	return ret;
	}

	*pvm = vm;

	return 0;
	}

	int
	nvkm_vm_new(struct nvkm_device *device, u64 offset, u64 length, u64 mm_offset,
	struct lock_class_key key, struct nvkm_vm *pvm)
	{
	struct nvkm_mmu *mmu = device->mmu;
	if (!mmu->func->create)
	return -EINVAL;
	return mmu->func->create(mmu, offset, length, mm_offset, key, pvm);
	}

	static int
	nvkm_vm_link(struct nvkm_vm vm, struct nvkm_gpuobj pgd)
	{
	struct nvkm_mmu *mmu = vm->mmu;
	struct nvkm_vm_pgd *vpgd;
	int i;

	if (!pgd)
	return 0;

	vpgd = kzalloc(sizeof(*vpgd), GFP_KERNEL);
	if (!vpgd)
	return -ENOMEM;

	vpgd->obj = pgd;

	mutex_lock(&vm->mutex);
	for (i = vm->fpde; i <= vm->lpde; i++)
	mmu->func->map_pgt(pgd, i, vm->pgt[i - vm->fpde].mem);
	list_add(&vpgd->head, &vm->pgd_list);
	mutex_unlock(&vm->mutex);
	return 0;
	}

	static void
	nvkm_vm_unlink(struct nvkm_vm vm, struct nvkm_gpuobj mpgd)
	{
	struct nvkm_vm_pgd vpgd, tmp;

	if (!mpgd)
	return;

	mutex_lock(&vm->mutex);
	list_for_each_entry_safe(vpgd, tmp, &vm->pgd_list, head) {
	if (vpgd->obj == mpgd) {
	list_del(&vpgd->head);
	kfree(vpgd);
	break;
	}
	}
	mutex_unlock(&vm->mutex);
	}

	static void
	nvkm_vm_del(struct kref *kref)
	{
	struct nvkm_vm vm = container_of(kref, typeof(vm), refcount);
	struct nvkm_vm_pgd vpgd, tmp;

	list_for_each_entry_safe(vpgd, tmp, &vm->pgd_list, head) {
	nvkm_vm_unlink(vm, vpgd->obj);
	}

	nvkm_mm_fini(&vm->mm);
	vfree(vm->pgt);
	kfree(vm);
	}

	int
	nvkm_vm_ref(struct nvkm_vm ref, struct nvkm_vm ptr, struct nvkm_gpuobj pgd)
	{
	if (ref) {
	int ret = nvkm_vm_link(ref, pgd);
	if (ret)
	return ret;

	kref_get(&ref->refcount);
	}

	if (*ptr) {
	nvkm_vm_unlink(*ptr, pgd);
	kref_put(&(*ptr)->refcount, nvkm_vm_del);
	}

	*ptr = ref;
	return 0;
	}

	static int
	nvkm_mmu_oneinit(struct nvkm_subdev *subdev)
	{
	struct nvkm_mmu *mmu = nvkm_mmu(subdev);
	if (mmu->func->oneinit)
	return mmu->func->oneinit(mmu);
	return 0;
	}

	static int
	nvkm_mmu_init(struct nvkm_subdev *subdev)
	{
	struct nvkm_mmu *mmu = nvkm_mmu(subdev);
	if (mmu->func->init)
	mmu->func->init(mmu);
	return 0;
	}

	static void *
	nvkm_mmu_dtor(struct nvkm_subdev *subdev)
	{
	struct nvkm_mmu *mmu = nvkm_mmu(subdev);
	if (mmu->func->dtor)
	return mmu->func->dtor(mmu);
	return mmu;
	}

	static const struct nvkm_subdev_func
	nvkm_mmu = {
	.dtor = nvkm_mmu_dtor,
	.oneinit = nvkm_mmu_oneinit,
	.init = nvkm_mmu_init,
	};

	void
	nvkm_mmu_ctor(const struct nvkm_mmu_func func, struct nvkm_device device,
	int index, struct nvkm_mmu *mmu)
	{
	nvkm_subdev_ctor(&nvkm_mmu, device, index, &mmu->subdev);
	mmu->func = func;
	mmu->limit = func->limit;
	mmu->dma_bits = func->dma_bits;
	mmu->lpg_shift = func->lpg_shift;
	}

	int
	nvkm_mmu_new_(const struct nvkm_mmu_func func, struct nvkm_device device,
	int index, struct nvkm_mmu **pmmu)
	{
	if (!(pmmu = kzalloc(sizeof(*pmmu), GFP_KERNEL)))
	return -ENOMEM;
	nvkm_mmu_ctor(func, device, index, *pmmu);
	return 0;
	}