/*
 * Copyright 2008 Advanced Micro Devices, Inc.
 * Copyright 2008 Red Hat Inc.
 * Copyright 2009 Jerome Glisse.
 *
 * 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: Dave Airlie
 *          Alex Deucher
 *          Jerome Glisse
 */

#include <linux/dma-fence-array.h>
#include <linux/interval_tree_generic.h>
#include <linux/idr.h>
#include <linux/dma-buf.h>

#include <drm/amdgpu_drm.h>
#include <drm/drm_drv.h>
#include <drm/ttm/ttm_tt.h>
#include <drm/drm_exec.h>
#include "amdgpu.h"
#include "amdgpu_vm.h"
#include "amdgpu_trace.h"
#include "amdgpu_amdkfd.h"
#include "amdgpu_gmc.h"
#include "amdgpu_xgmi.h"
#include "amdgpu_dma_buf.h"
#include "amdgpu_res_cursor.h"
#include "kfd_svm.h"

/**
 * DOC: GPUVM
 *
 * GPUVM is the MMU functionality provided on the GPU.
 * GPUVM is similar to the legacy GART on older asics, however
 * rather than there being a single global GART table
 * for the entire GPU, there can be multiple GPUVM page tables active
 * at any given time.  The GPUVM page tables can contain a mix
 * VRAM pages and system pages (both memory and MMIO) and system pages
 * can be mapped as snooped (cached system pages) or unsnooped
 * (uncached system pages).
 *
 * Each active GPUVM has an ID associated with it and there is a page table
 * linked with each VMID.  When executing a command buffer,
 * the kernel tells the engine what VMID to use for that command
 * buffer.  VMIDs are allocated dynamically as commands are submitted.
 * The userspace drivers maintain their own address space and the kernel
 * sets up their pages tables accordingly when they submit their
 * command buffers and a VMID is assigned.
 * The hardware supports up to 16 active GPUVMs at any given time.
 *
 * Each GPUVM is represented by a 1-2 or 1-5 level page table, depending
 * on the ASIC family.  GPUVM supports RWX attributes on each page as well
 * as other features such as encryption and caching attributes.
 *
 * VMID 0 is special.  It is the GPUVM used for the kernel driver.  In
 * addition to an aperture managed by a page table, VMID 0 also has
 * several other apertures.  There is an aperture for direct access to VRAM
 * and there is a legacy AGP aperture which just forwards accesses directly
 * to the matching system physical addresses (or IOVAs when an IOMMU is
 * present).  These apertures provide direct access to these memories without
 * incurring the overhead of a page table.  VMID 0 is used by the kernel
 * driver for tasks like memory management.
 *
 * GPU clients (i.e., engines on the GPU) use GPUVM VMIDs to access memory.
 * For user applications, each application can have their own unique GPUVM
 * address space.  The application manages the address space and the kernel
 * driver manages the GPUVM page tables for each process.  If an GPU client
 * accesses an invalid page, it will generate a GPU page fault, similar to
 * accessing an invalid page on a CPU.
 */

#define START(node) ((node)->start)
#define LAST(node) ((node)->last)

INTERVAL_TREE_DEFINE(struct amdgpu_bo_va_mapping, rb, uint64_t, __subtree_last,
		     START, LAST, static, amdgpu_vm_it)

#undef START
#undef LAST

/**
 * struct amdgpu_prt_cb - Helper to disable partial resident texture feature from a fence callback
 */
struct amdgpu_prt_cb {

	/**
	 * @adev: amdgpu device
	 */
	struct amdgpu_device *adev;

	/**
	 * @cb: callback
	 */
	struct dma_fence_cb cb;
};

/**
 * struct amdgpu_vm_tlb_seq_struct - Helper to increment the TLB flush sequence
 */
struct amdgpu_vm_tlb_seq_struct {
	/**
	 * @vm: pointer to the amdgpu_vm structure to set the fence sequence on
	 */
	struct amdgpu_vm *vm;

	/**
	 * @cb: callback
	 */
	struct dma_fence_cb cb;
};

/**
 * amdgpu_vm_assert_locked - check if VM is correctly locked
 * @vm: the VM which schould be tested
 *
 * Asserts that the VM root PD is locked.
 */
static void amdgpu_vm_assert_locked(struct amdgpu_vm *vm)
{
	dma_resv_assert_held(vm->root.bo->tbo.base.resv);
}

/* Initialize the amdgpu_vm_bo_status object */
static void amdgpu_vm_bo_status_init(struct amdgpu_vm_bo_status *lists)
{
	INIT_LIST_HEAD(&lists->evicted);
	INIT_LIST_HEAD(&lists->needs_update);
	INIT_LIST_HEAD(&lists->idle);
}

/*
 * Make sure we have the lock to modify the vm_bo status and return the object
 * with the status lists.
 */
static struct amdgpu_vm_bo_status *
amdgpu_vm_bo_lock_lists(struct amdgpu_vm_bo_base *vm_bo)
{
	struct amdgpu_vm *vm = vm_bo->vm;
	struct amdgpu_bo *bo = vm_bo->bo;

	if (amdgpu_vm_is_bo_always_valid(vm, bo)) {
		/* No extra locking needed, protected by the root PD resv lock */
		amdgpu_vm_assert_locked(vm);

		if (bo->tbo.type == ttm_bo_type_kernel)
			return &vm->kernel;

		return &vm->always_valid;
	}

	spin_lock(&vm_bo->vm->individual_lock);
	return &vm->individual;
}

/* Eventually unlock the status list lock again */
static void amdgpu_vm_bo_unlock_lists(struct amdgpu_vm_bo_base *vm_bo)
{
	if (amdgpu_vm_is_bo_always_valid(vm_bo->vm, vm_bo->bo))
		amdgpu_vm_assert_locked(vm_bo->vm);
	else
		spin_unlock(&vm_bo->vm->individual_lock);
}

/**
 * amdgpu_vm_is_bo_always_valid - check if the BO is VM always valid
 *
 * @vm: VM to test against.
 * @bo: BO to be tested.
 *
 * Returns true if the BO shares the dma_resv object with the root PD and is
 * always guaranteed to be valid inside the VM.
 */
bool amdgpu_vm_is_bo_always_valid(struct amdgpu_vm *vm, struct amdgpu_bo *bo)
{
	return bo && bo->tbo.base.resv == vm->root.bo->tbo.base.resv;
}

/**
 * amdgpu_vm_bo_evicted - vm_bo is evicted
 *
 * @vm_bo: vm_bo which is evicted
 *
 * State for vm_bo objects meaning the underlying BO was evicted and need to
 * move in place again.
 */
static void amdgpu_vm_bo_evicted(struct amdgpu_vm_bo_base *vm_bo)
{
	struct amdgpu_vm_bo_status *lists;

	lists = amdgpu_vm_bo_lock_lists(vm_bo);
	vm_bo->moved = true;
	list_move(&vm_bo->vm_status, &lists->evicted);
	amdgpu_vm_bo_unlock_lists(vm_bo);
}
/**
 * amdgpu_vm_bo_needs_update - vm_bo needs pagetable update
 *
 * @vm_bo: vm_bo which is out of date
 *
 * State for vm_bo objects meaning the underlying BO had mapping changes (move, PRT bind/unbind)
 * but the new location is not yet reflected in the page tables.
 */
static void amdgpu_vm_bo_needs_update(struct amdgpu_vm_bo_base *vm_bo)
{
	struct amdgpu_vm_bo_status *lists;
	struct amdgpu_bo *bo = vm_bo->bo;

	/*
	 * The root PD doesn't have a parent PDE and goes directly into the
	 * idle state.
	 */
	lists = amdgpu_vm_bo_lock_lists(vm_bo);
	if (bo && bo->tbo.type == ttm_bo_type_kernel && !bo->parent) {
		vm_bo->moved = false;
		list_move(&vm_bo->vm_status, &lists->idle);
	} else {
		list_move(&vm_bo->vm_status, &lists->needs_update);
	}
	amdgpu_vm_bo_unlock_lists(vm_bo);
}

/**
 * amdgpu_vm_bo_idle - vm_bo is idle
 *
 * @vm_bo: vm_bo which is now idle
 *
 * State for vm_bo objects meaning we are done with the state machine and no
 * further action is necessary.
 */
static void amdgpu_vm_bo_idle(struct amdgpu_vm_bo_base *vm_bo)
{
	struct amdgpu_vm_bo_status *lists;

	lists = amdgpu_vm_bo_lock_lists(vm_bo);
	if (!amdgpu_vm_is_bo_always_valid(vm_bo->vm, vm_bo->bo))
		vm_bo->moved = false;
	list_move(&vm_bo->vm_status, &lists->idle);
	amdgpu_vm_bo_unlock_lists(vm_bo);
}

/**
 * amdgpu_vm_bo_reset_state_machine - reset the vm_bo state machine
 * @vm: the VM which state machine to reset
 *
 * Move all vm_bo object in the VM into a state where their location will be
 * updated in the page tables again.
 */
static void amdgpu_vm_bo_reset_state_machine(struct amdgpu_vm *vm)
{
	struct amdgpu_vm_bo_base *vm_bo, *tmp;

	/*
	 * Don't use list splice here, we need the special handling for the root
	 * PD and set the moved flag appropriately.
	 */
	amdgpu_vm_assert_locked(vm);
	list_for_each_entry_safe(vm_bo, tmp, &vm->kernel.idle, vm_status)
		amdgpu_vm_bo_needs_update(vm_bo);
	list_for_each_entry_safe(vm_bo, tmp, &vm->always_valid.idle, vm_status)
		amdgpu_vm_bo_needs_update(vm_bo);

	spin_lock(&vm->individual_lock);
	list_for_each_entry_safe(vm_bo, tmp, &vm->individual.idle, vm_status) {
		vm_bo->moved = true;
		list_move(&vm_bo->vm_status, &vm->individual.needs_update);
	}
	spin_unlock(&vm->individual_lock);
}

/**
 * amdgpu_vm_update_shared - helper to update shared memory stat
 * @base: base structure for tracking BO usage in a VM
 *
 * Takes the vm stats_lock and updates the shared memory stat. If the basic
 * stat changed (e.g. buffer was moved) amdgpu_vm_update_stats need to be called
 * as well.
 */
static void amdgpu_vm_update_shared(struct amdgpu_vm_bo_base *base)
{
	struct amdgpu_vm *vm = base->vm;
	struct amdgpu_bo *bo = base->bo;
	uint64_t size = amdgpu_bo_size(bo);
	uint32_t bo_memtype = amdgpu_bo_mem_stats_placement(bo);
	bool shared;

	dma_resv_assert_held(bo->tbo.base.resv);
	spin_lock(&vm->stats_lock);
	shared = drm_gem_object_is_shared_for_memory_stats(&bo->tbo.base);
	if (base->shared != shared) {
		base->shared = shared;
		if (shared) {
			vm->stats[bo_memtype].drm.shared += size;
			vm->stats[bo_memtype].drm.private -= size;
		} else {
			vm->stats[bo_memtype].drm.shared -= size;
			vm->stats[bo_memtype].drm.private += size;
		}
	}
	spin_unlock(&vm->stats_lock);
}

/**
 * amdgpu_vm_bo_update_shared - callback when bo gets shared/unshared
 * @bo: amdgpu buffer object
 *
 * Update the per VM stats for all the vm if needed from private to shared or
 * vice versa.
 */
void amdgpu_vm_bo_update_shared(struct amdgpu_bo *bo)
{
	struct amdgpu_vm_bo_base *base;

	for (base = bo->vm_bo; base; base = base->next)
		amdgpu_vm_update_shared(base);
}

/**
 * amdgpu_vm_update_stats_locked - helper to update normal memory stat
 * @base: base structure for tracking BO usage in a VM
 * @res:  the ttm_resource to use for the purpose of accounting, may or may not
 *        be bo->tbo.resource
 * @sign: if we should add (+1) or subtract (-1) from the stat
 *
 * Caller need to have the vm stats_lock held. Useful for when multiple update
 * need to happen at the same time.
 */
static void amdgpu_vm_update_stats_locked(struct amdgpu_vm_bo_base *base,
					  struct ttm_resource *res, int sign)
{
	struct amdgpu_vm *vm = base->vm;
	struct amdgpu_bo *bo = base->bo;
	int64_t size = sign * amdgpu_bo_size(bo);
	uint32_t bo_memtype = amdgpu_bo_mem_stats_placement(bo);

	/* For drm-total- and drm-shared-, BO are accounted by their preferred
	 * placement, see also amdgpu_bo_mem_stats_placement.
	 */
	if (base->shared)
		vm->stats[bo_memtype].drm.shared += size;
	else
		vm->stats[bo_memtype].drm.private += size;

	if (res && res->mem_type < __AMDGPU_PL_NUM) {
		uint32_t res_memtype = res->mem_type;

		vm->stats[res_memtype].drm.resident += size;
		/* BO only count as purgeable if it is resident,
		 * since otherwise there's nothing to purge.
		 */
		if (bo->flags & AMDGPU_GEM_CREATE_DISCARDABLE)
			vm->stats[res_memtype].drm.purgeable += size;
		if (!(bo->preferred_domains &
		      amdgpu_mem_type_to_domain(res_memtype)))
			vm->stats[bo_memtype].evicted += size;
	}
}

/**
 * amdgpu_vm_update_stats - helper to update normal memory stat
 * @base: base structure for tracking BO usage in a VM
 * @res:  the ttm_resource to use for the purpose of accounting, may or may not
 *        be bo->tbo.resource
 * @sign: if we should add (+1) or subtract (-1) from the stat
 *
 * Updates the basic memory stat when bo is added/deleted/moved.
 */
void amdgpu_vm_update_stats(struct amdgpu_vm_bo_base *base,
			    struct ttm_resource *res, int sign)
{
	struct amdgpu_vm *vm = base->vm;

	spin_lock(&vm->stats_lock);
	amdgpu_vm_update_stats_locked(base, res, sign);
	spin_unlock(&vm->stats_lock);
}

/**
 * amdgpu_vm_bo_base_init - Adds bo to the list of bos associated with the vm
 *
 * @base: base structure for tracking BO usage in a VM
 * @vm: vm to which bo is to be added
 * @bo: amdgpu buffer object
 *
 * Initialize a bo_va_base structure and add it to the appropriate lists
 *
 */
void amdgpu_vm_bo_base_init(struct amdgpu_vm_bo_base *base,
			    struct amdgpu_vm *vm, struct amdgpu_bo *bo)
{
	base->vm = vm;
	base->bo = bo;
	base->next = NULL;
	INIT_LIST_HEAD(&base->vm_status);

	dma_resv_assert_held(vm->root.bo->tbo.base.resv);
	if (!bo)
		return;

	base->next = bo->vm_bo;
	bo->vm_bo = base;

	spin_lock(&vm->stats_lock);
	base->shared = drm_gem_object_is_shared_for_memory_stats(&bo->tbo.base);
	amdgpu_vm_update_stats_locked(base, bo->tbo.resource, +1);
	spin_unlock(&vm->stats_lock);

	if (!amdgpu_vm_is_bo_always_valid(vm, bo)) {
		amdgpu_vm_bo_idle(base);
		return;
	}

	ttm_bo_set_bulk_move(&bo->tbo, &vm->lru_bulk_move);

	/*
	 * When a per VM isn't in the desired domain put it into the evicted
	 * state to make sure that it gets validated on the next best occasion.
	 */
	if (bo->preferred_domains &
	    amdgpu_mem_type_to_domain(bo->tbo.resource->mem_type))
		amdgpu_vm_bo_needs_update(base);
	else
		amdgpu_vm_bo_evicted(base);
}

/**
 * amdgpu_vm_lock_pd - lock PD in drm_exec
 *
 * @vm: vm providing the BOs
 * @exec: drm execution context
 * @num_fences: number of extra fences to reserve
 *
 * Lock the VM root PD in the DRM execution context.
 */
int amdgpu_vm_lock_pd(struct amdgpu_vm *vm, struct drm_exec *exec,
		      unsigned int num_fences)
{
	/* We need at least two fences for the VM PD/PT updates */
	return drm_exec_prepare_obj(exec, &vm->root.bo->tbo.base,
				    2 + num_fences);
}

/**
 * amdgpu_vm_lock_individual - lock all BOs on the individual idle list
 * @vm: vm providing the BOs
 * @exec: drm execution context
 * @num_fences: number of extra fences to reserve
 *
 * Lock the BOs on the individual idle list in the DRM execution context.
 */
int amdgpu_vm_lock_individual(struct amdgpu_vm *vm, struct drm_exec *exec,
			      unsigned int num_fences)
{
	struct list_head *prev = &vm->individual.idle;
	struct amdgpu_bo_va *bo_va;
	struct amdgpu_bo *bo;
	int ret;

	/* We can only trust prev->next while holding the lock */
	spin_lock(&vm->individual_lock);
	while (!list_is_head(prev->next, &vm->individual.idle)) {
		bo_va = list_entry(prev->next, typeof(*bo_va), base.vm_status);

		bo = bo_va->base.bo;
		if (bo) {
			amdgpu_bo_ref(bo);
			spin_unlock(&vm->individual_lock);

			ret = drm_exec_prepare_obj(exec, &bo->tbo.base, num_fences);
			amdgpu_bo_unref(&bo);
			if (unlikely(ret))
				return ret;

			spin_lock(&vm->individual_lock);
		}
		prev = prev->next;
	}
	spin_unlock(&vm->individual_lock);

	return 0;
}

/**
 * amdgpu_vm_move_to_lru_tail - move all BOs to the end of LRU
 *
 * @adev: amdgpu device pointer
 * @vm: vm providing the BOs
 *
 * Move all BOs to the end of LRU and remember their positions to put them
 * together.
 */
void amdgpu_vm_move_to_lru_tail(struct amdgpu_device *adev,
				struct amdgpu_vm *vm)
{
	spin_lock(&adev->mman.bdev.lru_lock);
	ttm_lru_bulk_move_tail(&vm->lru_bulk_move);
	spin_unlock(&adev->mman.bdev.lru_lock);
}

/* Create scheduler entities for page table updates */
static int amdgpu_vm_init_entities(struct amdgpu_device *adev,
				   struct amdgpu_vm *vm)
{
	int r;

	r = drm_sched_entity_init(&vm->immediate, DRM_SCHED_PRIORITY_NORMAL,
				  adev->vm_manager.vm_pte_scheds,
				  adev->vm_manager.vm_pte_num_scheds, NULL);
	if (r)
		goto error;

	return drm_sched_entity_init(&vm->delayed, DRM_SCHED_PRIORITY_NORMAL,
				     adev->vm_manager.vm_pte_scheds,
				     adev->vm_manager.vm_pte_num_scheds, NULL);

error:
	drm_sched_entity_destroy(&vm->immediate);
	return r;
}

/* Destroy the entities for page table updates again */
static void amdgpu_vm_fini_entities(struct amdgpu_vm *vm)
{
	drm_sched_entity_destroy(&vm->immediate);
	drm_sched_entity_destroy(&vm->delayed);
}

/**
 * amdgpu_vm_generation - return the page table re-generation counter
 * @adev: the amdgpu_device
 * @vm: optional VM to check, might be NULL
 *
 * Returns a page table re-generation token to allow checking if submissions
 * are still valid to use this VM. The VM parameter might be NULL in which case
 * just the VRAM lost counter will be used.
 */
uint64_t amdgpu_vm_generation(struct amdgpu_device *adev, struct amdgpu_vm *vm)
{
	uint64_t result = (u64)atomic_read(&adev->vram_lost_counter) << 32;

	if (!vm)
		return result;

	result += lower_32_bits(vm->generation);
	/* Add one if the page tables will be re-generated on next CS */
	if (drm_sched_entity_error(&vm->delayed))
		++result;

	return result;
}

/**
 * amdgpu_vm_validate - validate evicted BOs tracked in the VM
 *
 * @adev: amdgpu device pointer
 * @vm: vm providing the BOs
 * @ticket: optional reservation ticket used to reserve the VM
 * @validate: callback to do the validation
 * @param: parameter for the validation callback
 *
 * Validate the page table BOs and per-VM BOs on command submission if
 * necessary. If a ticket is given, also try to validate evicted user queue
 * BOs. They must already be reserved with the given ticket.
 *
 * Returns:
 * Validation result.
 */
int amdgpu_vm_validate(struct amdgpu_device *adev, struct amdgpu_vm *vm,
		       struct ww_acquire_ctx *ticket,
		       int (*validate)(void *p, struct amdgpu_bo *bo),
		       void *param)
{
	uint64_t new_vm_generation = amdgpu_vm_generation(adev, vm);
	struct amdgpu_vm_bo_base *bo_base, *tmp;
	int r;

	dma_resv_assert_held(vm->root.bo->tbo.base.resv);
	if (vm->generation != new_vm_generation) {
		vm->generation = new_vm_generation;
		amdgpu_vm_bo_reset_state_machine(vm);
		amdgpu_vm_fini_entities(vm);
		r = amdgpu_vm_init_entities(adev, vm);
		if (r)
			return r;
	}

	list_for_each_entry_safe(bo_base, tmp, &vm->kernel.evicted, vm_status) {
		r = validate(param, bo_base->bo);
		if (r)
			return r;

		vm->update_funcs->map_table(to_amdgpu_bo_vm(bo_base->bo));
		bo_base->moved = true;
		amdgpu_vm_bo_needs_update(bo_base);
	}

	/*
	 * As soon as all page tables are in place we can start updating them
	 * again.
	 */
	amdgpu_vm_eviction_lock(vm);
	vm->evicting = false;
	amdgpu_vm_eviction_unlock(vm);

	list_for_each_entry_safe(bo_base, tmp, &vm->always_valid.evicted,
				 vm_status) {
		r = validate(param, bo_base->bo);
		if (r)
			return r;

		bo_base->moved = true;
		amdgpu_vm_bo_needs_update(bo_base);
	}

	if (!ticket)
		return 0;

	spin_lock(&vm->individual_lock);
restart:
	list_for_each_entry(bo_base, &vm->individual.evicted, vm_status) {
		struct amdgpu_bo *bo = bo_base->bo;

		if (dma_resv_locking_ctx(bo->tbo.base.resv) != ticket)
			continue;

		spin_unlock(&vm->individual_lock);

		r = validate(param, bo);
		if (r)
			return r;

		bo_base->moved = true;
		amdgpu_vm_bo_needs_update(bo_base);

		/* It's a bit inefficient to always jump back to the start, but
		 * we would need to re-structure the KFD for properly fixing
		 * that.
		 */
		spin_lock(&vm->individual_lock);
		goto restart;
	}
	spin_unlock(&vm->individual_lock);

	return 0;
}

/**
 * amdgpu_vm_ready - check VM is ready for updates
 *
 * @vm: VM to check
 *
 * Check if all VM PDs/PTs are ready for updates
 *
 * Returns:
 * True if VM is not evicting and all VM entities are not stopped
 */
bool amdgpu_vm_ready(struct amdgpu_vm *vm)
{
	bool ret;

	amdgpu_vm_assert_locked(vm);

	amdgpu_vm_eviction_lock(vm);
	ret = !vm->evicting;
	amdgpu_vm_eviction_unlock(vm);

	ret &= list_empty(&vm->kernel.evicted);

	spin_lock(&vm->immediate.lock);
	ret &= !vm->immediate.stopped;
	spin_unlock(&vm->immediate.lock);

	spin_lock(&vm->delayed.lock);
	ret &= !vm->delayed.stopped;
	spin_unlock(&vm->delayed.lock);

	return ret;
}

/**
 * amdgpu_vm_check_compute_bug - check whether asic has compute vm bug
 *
 * @adev: amdgpu_device pointer
 */
void amdgpu_vm_check_compute_bug(struct amdgpu_device *adev)
{
	const struct amdgpu_ip_block *ip_block;
	bool has_compute_vm_bug;
	struct amdgpu_ring *ring;
	int i;

	has_compute_vm_bug = false;

	ip_block = amdgpu_device_ip_get_ip_block(adev, AMD_IP_BLOCK_TYPE_GFX);
	if (ip_block) {
		/* Compute has a VM bug for GFX version < 7.
		   Compute has a VM bug for GFX 8 MEC firmware version < 673.*/
		if (ip_block->version->major <= 7)
			has_compute_vm_bug = true;
		else if (ip_block->version->major == 8)
			if (adev->gfx.mec_fw_version < 673)
				has_compute_vm_bug = true;
	}

	for (i = 0; i < adev->num_rings; i++) {
		ring = adev->rings[i];
		if (ring->funcs->type == AMDGPU_RING_TYPE_COMPUTE)
			/* only compute rings */
			ring->has_compute_vm_bug = has_compute_vm_bug;
		else
			ring->has_compute_vm_bug = false;
	}
}

/**
 * amdgpu_vm_need_pipeline_sync - Check if pipe sync is needed for job.
 *
 * @ring: ring on which the job will be submitted
 * @job: job to submit
 *
 * Returns:
 * True if sync is needed.
 */
bool amdgpu_vm_need_pipeline_sync(struct amdgpu_ring *ring,
				  struct amdgpu_job *job)
{
	struct amdgpu_device *adev = ring->adev;
	unsigned vmhub = ring->vm_hub;
	struct amdgpu_vmid_mgr *id_mgr = &adev->vm_manager.id_mgr[vmhub];

	if (job->vmid == 0)
		return false;

	if (job->vm_needs_flush || ring->has_compute_vm_bug)
		return true;

	if (ring->funcs->emit_gds_switch && job->gds_switch_needed)
		return true;

	if (amdgpu_vmid_had_gpu_reset(adev, &id_mgr->ids[job->vmid]))
		return true;

	return false;
}

/**
 * amdgpu_vm_flush - hardware flush the vm
 *
 * @ring: ring to use for flush
 * @job:  related job
 * @need_pipe_sync: is pipe sync needed
 * @emit_spm_needed: does the caller need to emit spm
 * @emit_gds_needed: does the caller need to emit gds
 *
 * Emit a VM flush when it is necessary.
 */
void amdgpu_vm_flush(struct amdgpu_ring *ring, struct amdgpu_job *job,
		     bool *need_pipe_sync, bool *emit_spm_needed,
		     bool *emit_gds_needed)
{
	struct amdgpu_device *adev = ring->adev;
	struct amdgpu_isolation *isolation =
		&adev->isolation[ring->xcp_id == AMDGPU_XCP_NO_PARTITION ?
				 0 : ring->xcp_id];
	unsigned vmhub = ring->vm_hub;
	struct amdgpu_vmid_mgr *id_mgr = &adev->vm_manager.id_mgr[vmhub];
	struct amdgpu_vmid *id = &id_mgr->ids[job->vmid];
	bool spm_update_needed = adev->gfx.rlc.funcs->update_spm_vmid &&
		job->spm_update_needed;
	bool gds_switch_needed = ring->funcs->emit_gds_switch &&
		job->gds_switch_needed;
	bool vm_flush_needed = job->vm_needs_flush;
	bool cleaner_shader_needed = false;
	bool pasid_mapping_needed = false;
	struct dma_fence *fence = NULL;
	unsigned int patch = 0;
	bool emit_fence;

	if (amdgpu_vmid_had_gpu_reset(adev, id)) {
		gds_switch_needed = true;
		vm_flush_needed = true;
		pasid_mapping_needed = true;
		spm_update_needed = true;
	}

	mutex_lock(&id_mgr->lock);
	if (id->pasid != job->pasid || !id->pasid_mapping ||
	    !dma_fence_is_signaled(id->pasid_mapping))
		pasid_mapping_needed = true;
	mutex_unlock(&id_mgr->lock);

	gds_switch_needed &= !!ring->funcs->emit_gds_switch;
	spm_update_needed &= !!adev->gfx.rlc.funcs->update_spm_vmid;
	vm_flush_needed &= !!ring->funcs->emit_vm_flush  &&
			job->vm_pd_addr != AMDGPU_BO_INVALID_OFFSET;
	pasid_mapping_needed &= adev->gmc.gmc_funcs->emit_pasid_mapping &&
		ring->funcs->emit_wreg;

	cleaner_shader_needed = job->run_cleaner_shader &&
		adev->gfx.enable_cleaner_shader &&
		ring->funcs->emit_cleaner_shader && job->base.s_fence &&
		&job->base.s_fence->scheduled == isolation->spearhead;

	emit_fence = vm_flush_needed || pasid_mapping_needed ||
		cleaner_shader_needed;

	*emit_spm_needed = spm_update_needed;
	if (spm_update_needed && emit_fence)
		*emit_spm_needed = false;

	*emit_gds_needed = gds_switch_needed;
	if (gds_switch_needed && emit_fence)
		*emit_gds_needed = false;

	if (!emit_fence)
		return;

	amdgpu_ring_ib_begin(ring);

	/* There is no matching insert_end for this on purpose for the vm flush.
	 * The IB portion of the submission has both.  Having multiple
	 * insert_start sequences is ok, but you can only have one insert_end
	 * per submission based on the way VCN FW works.  For JPEG
	 * you can as many insert_start and insert_end sequences as you like as
	 * long as the rest of the packets come between start and end sequences.
	 */
	if (ring->funcs->insert_start)
		ring->funcs->insert_start(ring);

	if (ring->funcs->init_cond_exec)
		patch = amdgpu_ring_init_cond_exec(ring,
						   ring->cond_exe_gpu_addr);

	if (*need_pipe_sync) {
		amdgpu_ring_emit_pipeline_sync(ring);
		*need_pipe_sync = false;
	}

	if (cleaner_shader_needed)
		ring->funcs->emit_cleaner_shader(ring);

	if (vm_flush_needed) {
		trace_amdgpu_vm_flush(ring, job->vmid, job->vm_pd_addr);
		amdgpu_ring_emit_vm_flush(ring, job->vmid, job->vm_pd_addr);
	}

	if (pasid_mapping_needed)
		amdgpu_gmc_emit_pasid_mapping(ring, job->vmid, job->pasid);

	if (spm_update_needed)
		adev->gfx.rlc.funcs->update_spm_vmid(adev, ring->xcc_id, ring, job->vmid);

	if (gds_switch_needed)
		amdgpu_ring_emit_gds_switch(ring, job->vmid, job->gds_base,
						    job->gds_size, job->gws_base,
						    job->gws_size, job->oa_base,
						    job->oa_size);

	amdgpu_fence_emit(ring, job->hw_vm_fence, 0);
	fence = &job->hw_vm_fence->base;
	/* get a ref for the job */
	dma_fence_get(fence);

	if (vm_flush_needed) {
		mutex_lock(&id_mgr->lock);
		dma_fence_put(id->last_flush);
		id->last_flush = dma_fence_get(fence);
		id->current_gpu_reset_count =
			atomic_read(&adev->gpu_reset_counter);
		mutex_unlock(&id_mgr->lock);
	}

	if (pasid_mapping_needed) {
		mutex_lock(&id_mgr->lock);
		id->pasid = job->pasid;
		dma_fence_put(id->pasid_mapping);
		id->pasid_mapping = dma_fence_get(fence);
		mutex_unlock(&id_mgr->lock);
	}

	/*
	 * Make sure that all other submissions wait for the cleaner shader to
	 * finish before we push them to the HW.
	 */
	if (cleaner_shader_needed) {
		trace_amdgpu_cleaner_shader(ring, fence);
		mutex_lock(&adev->enforce_isolation_mutex);
		dma_fence_put(isolation->spearhead);
		isolation->spearhead = dma_fence_get(fence);
		mutex_unlock(&adev->enforce_isolation_mutex);
	}
	dma_fence_put(fence);

	amdgpu_ring_patch_cond_exec(ring, patch);

	/*
	 * Sync CE with ME to prevent CE from fetching the next CE IB
	 * before the context switch is done. This is emitted before
	 * the first IB of a job submission after a context switch.
	 * The double SWITCH_BUFFER here *cannot* be skipped by COND_EXEC.
	 */
	if (ring->funcs->emit_switch_buffer) {
		amdgpu_ring_emit_switch_buffer(ring);
		amdgpu_ring_emit_switch_buffer(ring);
	}

	amdgpu_ring_ib_end(ring);
}

/**
 * amdgpu_vm_bo_find - find the bo_va for a specific vm & bo
 *
 * @vm: requested vm
 * @bo: requested buffer object
 *
 * Find @bo inside the requested vm.
 * Search inside the @bos vm list for the requested vm
 * Returns the found bo_va or NULL if none is found
 *
 * Object has to be reserved!
 *
 * Returns:
 * Found bo_va or NULL.
 */
struct amdgpu_bo_va *amdgpu_vm_bo_find(struct amdgpu_vm *vm,
				       struct amdgpu_bo *bo)
{
	struct amdgpu_vm_bo_base *base;

	for (base = bo->vm_bo; base; base = base->next) {
		if (base->vm != vm)
			continue;

		return container_of(base, struct amdgpu_bo_va, base);
	}
	return NULL;
}

/**
 * amdgpu_vm_map_gart - Resolve gart mapping of addr
 *
 * @pages_addr: optional DMA address to use for lookup
 * @addr: the unmapped addr
 *
 * Look up the physical address of the page that the pte resolves
 * to.
 *
 * Returns:
 * The pointer for the page table entry.
 */
uint64_t amdgpu_vm_map_gart(const dma_addr_t *pages_addr, uint64_t addr)
{
	uint64_t result;

	/* page table offset */
	result = pages_addr[addr >> PAGE_SHIFT];

	/* in case cpu page size != gpu page size*/
	result |= addr & (~PAGE_MASK);

	result &= 0xFFFFFFFFFFFFF000ULL;

	return result;
}

/**
 * amdgpu_vm_update_pdes - make sure that all directories are valid
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @immediate: submit immediately to the paging queue
 *
 * Makes sure all directories are up to date.
 *
 * Returns:
 * 0 for success, error for failure.
 */
int amdgpu_vm_update_pdes(struct amdgpu_device *adev,
			  struct amdgpu_vm *vm, bool immediate)
{
	struct amdgpu_vm_update_params params;
	struct amdgpu_vm_bo_base *entry, *tmp;
	bool flush_tlb_needed = false;
	int r, idx;

	amdgpu_vm_assert_locked(vm);

	if (list_empty(&vm->kernel.needs_update))
		return 0;

	if (!drm_dev_enter(adev_to_drm(adev), &idx))
		return -ENODEV;

	memset(&params, 0, sizeof(params));
	params.adev = adev;
	params.vm = vm;
	params.immediate = immediate;

	r = vm->update_funcs->prepare(&params, NULL,
				      AMDGPU_KERNEL_JOB_ID_VM_UPDATE_PDES);
	if (r)
		goto error;

	list_for_each_entry(entry, &vm->kernel.needs_update, vm_status) {
		/* vm_flush_needed after updating moved PDEs */
		flush_tlb_needed |= entry->moved;

		r = amdgpu_vm_pde_update(&params, entry);
		if (r)
			goto error;
	}

	r = vm->update_funcs->commit(&params, &vm->last_update);
	if (r)
		goto error;

	if (flush_tlb_needed)
		atomic64_inc(&vm->tlb_seq);

	list_for_each_entry_safe(entry, tmp, &vm->kernel.needs_update,
				 vm_status)
		amdgpu_vm_bo_idle(entry);

error:
	drm_dev_exit(idx);
	return r;
}

/**
 * amdgpu_vm_tlb_seq_cb - make sure to increment tlb sequence
 * @fence: unused
 * @cb: the callback structure
 *
 * Increments the tlb sequence to make sure that future CS execute a VM flush.
 */
static void amdgpu_vm_tlb_seq_cb(struct dma_fence *fence,
				 struct dma_fence_cb *cb)
{
	struct amdgpu_vm_tlb_seq_struct *tlb_cb;

	tlb_cb = container_of(cb, typeof(*tlb_cb), cb);
	atomic64_inc(&tlb_cb->vm->tlb_seq);
	kfree(tlb_cb);
}

/**
 * amdgpu_vm_tlb_flush - prepare TLB flush
 *
 * @params: parameters for update
 * @fence: input fence to sync TLB flush with
 * @tlb_cb: the callback structure
 *
 * Increments the tlb sequence to make sure that future CS execute a VM flush.
 */
static void
amdgpu_vm_tlb_flush(struct amdgpu_vm_update_params *params,
		    struct dma_fence **fence,
		    struct amdgpu_vm_tlb_seq_struct *tlb_cb)
{
	struct amdgpu_vm *vm = params->vm;

	tlb_cb->vm = vm;
	if (!fence || !*fence) {
		amdgpu_vm_tlb_seq_cb(NULL, &tlb_cb->cb);
		return;
	}

	if (!dma_fence_add_callback(*fence, &tlb_cb->cb,
				    amdgpu_vm_tlb_seq_cb)) {
		dma_fence_put(vm->last_tlb_flush);
		vm->last_tlb_flush = dma_fence_get(*fence);
	} else {
		amdgpu_vm_tlb_seq_cb(NULL, &tlb_cb->cb);
	}

	/* Prepare a TLB flush fence to be attached to PTs */
	/* The check for need_tlb_fence should be dropped once we
	 * sort out the issues with KIQ/MES TLB invalidation timeouts.
	 */
	if (!params->unlocked && vm->need_tlb_fence) {
		amdgpu_vm_tlb_fence_create(params->adev, vm, fence);

		/* Makes sure no PD/PT is freed before the flush */
		dma_resv_add_fence(vm->root.bo->tbo.base.resv, *fence,
				   DMA_RESV_USAGE_BOOKKEEP);
	}
}

/**
 * amdgpu_vm_update_range - update a range in the vm page table
 *
 * @adev: amdgpu_device pointer to use for commands
 * @vm: the VM to update the range
 * @immediate: immediate submission in a page fault
 * @unlocked: unlocked invalidation during MM callback
 * @flush_tlb: trigger tlb invalidation after update completed
 * @allow_override: change MTYPE for local NUMA nodes
 * @sync: fences we need to sync to
 * @start: start of mapped range
 * @last: last mapped entry
 * @flags: flags for the entries
 * @offset: offset into nodes and pages_addr
 * @vram_base: base for vram mappings
 * @res: ttm_resource to map
 * @pages_addr: DMA addresses to use for mapping
 * @fence: optional resulting fence
 *
 * Fill in the page table entries between @start and @last.
 *
 * Returns:
 * 0 for success, negative erro code for failure.
 */
int amdgpu_vm_update_range(struct amdgpu_device *adev, struct amdgpu_vm *vm,
			   bool immediate, bool unlocked, bool flush_tlb,
			   bool allow_override, struct amdgpu_sync *sync,
			   uint64_t start, uint64_t last, uint64_t flags,
			   uint64_t offset, uint64_t vram_base,
			   struct ttm_resource *res, dma_addr_t *pages_addr,
			   struct dma_fence **fence)
{
	struct amdgpu_vm_tlb_seq_struct *tlb_cb;
	struct amdgpu_vm_update_params params;
	struct amdgpu_res_cursor cursor;
	int r, idx;

	if (!drm_dev_enter(adev_to_drm(adev), &idx))
		return -ENODEV;

	tlb_cb = kmalloc_obj(*tlb_cb);
	if (!tlb_cb) {
		drm_dev_exit(idx);
		return -ENOMEM;
	}

	/* Vega20+XGMI where PTEs get inadvertently cached in L2 texture cache,
	 * heavy-weight flush TLB unconditionally.
	 */
	flush_tlb |= adev->gmc.xgmi.num_physical_nodes &&
		     amdgpu_ip_version(adev, GC_HWIP, 0) == IP_VERSION(9, 4, 0);

	/*
	 * On GFX8 and older any 8 PTE block with a valid bit set enters the TLB
	 */
	flush_tlb |= amdgpu_ip_version(adev, GC_HWIP, 0) < IP_VERSION(9, 0, 0);

	memset(&params, 0, sizeof(params));
	params.adev = adev;
	params.vm = vm;
	params.immediate = immediate;
	params.pages_addr = pages_addr;
	params.unlocked = unlocked;
	params.needs_flush = flush_tlb;
	params.override_pte = allow_override && adev->gmc.override_pte;
	INIT_LIST_HEAD(&params.tlb_flush_waitlist);

	amdgpu_vm_eviction_lock(vm);
	if (vm->evicting) {
		r = -EBUSY;
		goto error_free;
	}

	if (!unlocked && !dma_fence_is_signaled(vm->last_unlocked)) {
		struct dma_fence *tmp = dma_fence_get_stub();

		amdgpu_bo_fence(vm->root.bo, vm->last_unlocked, true);
		swap(vm->last_unlocked, tmp);
		dma_fence_put(tmp);
	}

	r = vm->update_funcs->prepare(&params, sync,
				      AMDGPU_KERNEL_JOB_ID_VM_UPDATE_RANGE);
	if (r)
		goto error_free;

	amdgpu_res_first(pages_addr ? NULL : res, offset,
			 (last - start + 1) * AMDGPU_GPU_PAGE_SIZE, &cursor);
	while (cursor.remaining) {
		uint64_t tmp, num_entries, addr;

		num_entries = cursor.size >> AMDGPU_GPU_PAGE_SHIFT;
		if (pages_addr) {
			bool contiguous = true;

			if (num_entries > AMDGPU_GPU_PAGES_IN_CPU_PAGE) {
				uint64_t pfn = cursor.start >> PAGE_SHIFT;
				uint64_t count;

				contiguous = pages_addr[pfn + 1] ==
					pages_addr[pfn] + PAGE_SIZE;

				tmp = num_entries /
					AMDGPU_GPU_PAGES_IN_CPU_PAGE;
				for (count = 2; count < tmp; ++count) {
					uint64_t idx = pfn + count;

					if (contiguous != (pages_addr[idx] ==
					    pages_addr[idx - 1] + PAGE_SIZE))
						break;
				}
				if (!contiguous)
					count--;
				num_entries = count *
					AMDGPU_GPU_PAGES_IN_CPU_PAGE;
			}

			if (!contiguous) {
				addr = cursor.start;
				params.pages_addr = pages_addr;
			} else {
				addr = pages_addr[cursor.start >> PAGE_SHIFT];
				params.pages_addr = NULL;
			}

		} else if (flags & (AMDGPU_PTE_VALID | AMDGPU_PTE_PRT_FLAG(adev))) {
			addr = vram_base + cursor.start;
		} else {
			addr = 0;
		}

		tmp = start + num_entries;
		r = amdgpu_vm_ptes_update(&params, start, tmp, addr, flags);
		if (r)
			goto error_free;

		amdgpu_res_next(&cursor, num_entries * AMDGPU_GPU_PAGE_SIZE);
		start = tmp;
	}

	r = vm->update_funcs->commit(&params, fence);
	if (r)
		goto error_free;

	if (params.needs_flush) {
		amdgpu_vm_tlb_flush(&params, fence, tlb_cb);
		tlb_cb = NULL;
	}

	amdgpu_vm_pt_free_list(adev, &params);

error_free:
	kfree(tlb_cb);
	amdgpu_vm_eviction_unlock(vm);
	drm_dev_exit(idx);
	return r;
}

void amdgpu_vm_get_memory(struct amdgpu_vm *vm,
			  struct amdgpu_mem_stats stats[__AMDGPU_PL_NUM])
{
	spin_lock(&vm->stats_lock);
	memcpy(stats, vm->stats, sizeof(*stats) * __AMDGPU_PL_NUM);
	spin_unlock(&vm->stats_lock);
}

/**
 * amdgpu_vm_bo_update - update all BO mappings in the vm page table
 *
 * @adev: amdgpu_device pointer
 * @bo_va: requested BO and VM object
 * @clear: if true clear the entries
 *
 * Fill in the page table entries for @bo_va.
 *
 * Returns:
 * 0 for success, -EINVAL for failure.
 */
int amdgpu_vm_bo_update(struct amdgpu_device *adev, struct amdgpu_bo_va *bo_va,
			bool clear)
{
	struct amdgpu_bo *bo = bo_va->base.bo;
	struct amdgpu_vm *vm = bo_va->base.vm;
	struct amdgpu_bo_va_mapping *mapping;
	struct dma_fence **last_update;
	dma_addr_t *pages_addr = NULL;
	struct ttm_resource *mem;
	struct amdgpu_sync sync;
	bool flush_tlb = clear;
	uint64_t vram_base;
	uint64_t flags;
	bool uncached;
	int r;

	amdgpu_sync_create(&sync);
	if (clear) {
		mem = NULL;

		/* Implicitly sync to command submissions in the same VM before
		 * unmapping.
		 */
		r = amdgpu_sync_resv(adev, &sync, vm->root.bo->tbo.base.resv,
				     AMDGPU_SYNC_EQ_OWNER, vm);
		if (r)
			goto error_free;
		if (bo) {
			r = amdgpu_sync_kfd(&sync, bo->tbo.base.resv);
			if (r)
				goto error_free;
		}
	} else if (!bo) {
		mem = NULL;

		/* PRT map operations don't need to sync to anything. */

	} else {
		struct drm_gem_object *obj = &bo->tbo.base;

		if (drm_gem_is_imported(obj) && bo_va->is_xgmi) {
			struct dma_buf *dma_buf = obj->import_attach->dmabuf;
			struct drm_gem_object *gobj = dma_buf->priv;
			struct amdgpu_bo *abo = gem_to_amdgpu_bo(gobj);

			if (abo->tbo.resource &&
			    abo->tbo.resource->mem_type == TTM_PL_VRAM)
				bo = gem_to_amdgpu_bo(gobj);
		}
		mem = bo->tbo.resource;
		if (mem && (mem->mem_type == TTM_PL_TT ||
			    mem->mem_type == AMDGPU_PL_PREEMPT))
			pages_addr = bo->tbo.ttm->dma_address;

		/* Implicitly sync to moving fences before mapping anything */
		r = amdgpu_sync_resv(adev, &sync, bo->tbo.base.resv,
				     AMDGPU_SYNC_EXPLICIT, vm);
		if (r)
			goto error_free;
	}

	if (bo) {
		struct amdgpu_device *bo_adev;

		flags = amdgpu_ttm_tt_pte_flags(adev, bo->tbo.ttm, mem);

		if (amdgpu_bo_encrypted(bo))
			flags |= AMDGPU_PTE_TMZ;

		bo_adev = amdgpu_ttm_adev(bo->tbo.bdev);
		vram_base = bo_adev->vm_manager.vram_base_offset;
		uncached = (bo->flags & AMDGPU_GEM_CREATE_UNCACHED) != 0;
	} else {
		flags = 0x0;
		vram_base = 0;
		uncached = false;
	}

	if (clear || amdgpu_vm_is_bo_always_valid(vm, bo))
		last_update = &vm->last_update;
	else
		last_update = &bo_va->last_pt_update;

	if (!clear && bo_va->base.moved) {
		flush_tlb = true;
		list_splice_init(&bo_va->valids, &bo_va->invalids);

	} else if (bo_va->cleared != clear) {
		list_splice_init(&bo_va->valids, &bo_va->invalids);
	}

	list_for_each_entry(mapping, &bo_va->invalids, list) {
		uint64_t update_flags = flags;

		/* normally,bo_va->flags only contians READABLE and WIRTEABLE bit go here
		 * but in case of something, we filter the flags in first place
		 */
		if (!(mapping->flags & AMDGPU_VM_PAGE_READABLE))
			update_flags &= ~AMDGPU_PTE_READABLE;
		if (!(mapping->flags & AMDGPU_VM_PAGE_WRITEABLE))
			update_flags &= ~AMDGPU_PTE_WRITEABLE;

		/* Apply ASIC specific mapping flags */
		amdgpu_gmc_get_vm_pte(adev, vm, bo, mapping->flags,
				      &update_flags);

		trace_amdgpu_vm_bo_update(mapping);

		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb,
					   !uncached, &sync, mapping->start,
					   mapping->last, update_flags,
					   mapping->offset, vram_base, mem,
					   pages_addr, last_update);
		if (r)
			goto error_free;
	}

	/* If the BO is not in its preferred location add it back to
	 * the evicted list so that it gets validated again on the
	 * next command submission.
	 */
	if (amdgpu_vm_is_bo_always_valid(vm, bo)) {
		if (bo->tbo.resource &&
		    !(bo->preferred_domains &
		      amdgpu_mem_type_to_domain(bo->tbo.resource->mem_type)))
			amdgpu_vm_bo_evicted(&bo_va->base);
		else
			amdgpu_vm_bo_idle(&bo_va->base);
	} else if (bo) {
		/*
		 * A PRT/sparse mapping has no BO and is kept off the vm_bo
		 * state lists (see amdgpu_vm_bo_base_init()); putting it on the
		 * idle list here would let amdgpu_vm_handle_moved() dereference
		 * the NULL bo after a reset.
		 */
		amdgpu_vm_bo_idle(&bo_va->base);
	}

	list_splice_init(&bo_va->invalids, &bo_va->valids);
	bo_va->cleared = clear;
	bo_va->base.moved = false;

	if (trace_amdgpu_vm_bo_mapping_enabled()) {
		list_for_each_entry(mapping, &bo_va->valids, list)
			trace_amdgpu_vm_bo_mapping(mapping);
	}

error_free:
	amdgpu_sync_free(&sync);
	return r;
}

/**
 * amdgpu_vm_update_prt_state - update the global PRT state
 *
 * @adev: amdgpu_device pointer
 */
static void amdgpu_vm_update_prt_state(struct amdgpu_device *adev)
{
	unsigned long flags;
	bool enable;

	spin_lock_irqsave(&adev->vm_manager.prt_lock, flags);
	enable = !!atomic_read(&adev->vm_manager.num_prt_users);
	adev->gmc.gmc_funcs->set_prt(adev, enable);
	spin_unlock_irqrestore(&adev->vm_manager.prt_lock, flags);
}

/**
 * amdgpu_vm_prt_get - add a PRT user
 *
 * @adev: amdgpu_device pointer
 */
static void amdgpu_vm_prt_get(struct amdgpu_device *adev)
{
	if (!adev->gmc.gmc_funcs->set_prt)
		return;

	if (atomic_inc_return(&adev->vm_manager.num_prt_users) == 1)
		amdgpu_vm_update_prt_state(adev);
}

/**
 * amdgpu_vm_prt_put - drop a PRT user
 *
 * @adev: amdgpu_device pointer
 */
static void amdgpu_vm_prt_put(struct amdgpu_device *adev)
{
	if (atomic_dec_return(&adev->vm_manager.num_prt_users) == 0)
		amdgpu_vm_update_prt_state(adev);
}

/**
 * amdgpu_vm_prt_cb - callback for updating the PRT status
 *
 * @fence: fence for the callback
 * @_cb: the callback function
 */
static void amdgpu_vm_prt_cb(struct dma_fence *fence, struct dma_fence_cb *_cb)
{
	struct amdgpu_prt_cb *cb = container_of(_cb, struct amdgpu_prt_cb, cb);

	amdgpu_vm_prt_put(cb->adev);
	kfree(cb);
}

/**
 * amdgpu_vm_add_prt_cb - add callback for updating the PRT status
 *
 * @adev: amdgpu_device pointer
 * @fence: fence for the callback
 */
static void amdgpu_vm_add_prt_cb(struct amdgpu_device *adev,
				 struct dma_fence *fence)
{
	struct amdgpu_prt_cb *cb;

	if (!adev->gmc.gmc_funcs->set_prt)
		return;

	cb = kmalloc_obj(struct amdgpu_prt_cb);
	if (!cb) {
		/* Last resort when we are OOM */
		if (fence)
			dma_fence_wait(fence, false);

		amdgpu_vm_prt_put(adev);
	} else {
		cb->adev = adev;
		if (!fence || dma_fence_add_callback(fence, &cb->cb,
						     amdgpu_vm_prt_cb))
			amdgpu_vm_prt_cb(fence, &cb->cb);
	}
}

/**
 * amdgpu_vm_free_mapping - free a mapping
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @mapping: mapping to be freed
 * @fence: fence of the unmap operation
 *
 * Free a mapping and make sure we decrease the PRT usage count if applicable.
 */
static void amdgpu_vm_free_mapping(struct amdgpu_device *adev,
				   struct amdgpu_vm *vm,
				   struct amdgpu_bo_va_mapping *mapping,
				   struct dma_fence *fence)
{
	if (mapping->flags & AMDGPU_VM_PAGE_PRT)
		amdgpu_vm_add_prt_cb(adev, fence);
	kfree(mapping);
}

/**
 * amdgpu_vm_prt_fini - finish all prt mappings
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 *
 * Register a cleanup callback to disable PRT support after VM dies.
 */
static void amdgpu_vm_prt_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm)
{
	struct dma_resv *resv = vm->root.bo->tbo.base.resv;
	struct dma_resv_iter cursor;
	struct dma_fence *fence;

	dma_resv_for_each_fence(&cursor, resv, DMA_RESV_USAGE_BOOKKEEP, fence) {
		/* Add a callback for each fence in the reservation object */
		amdgpu_vm_prt_get(adev);
		amdgpu_vm_add_prt_cb(adev, fence);
	}
}

/**
 * amdgpu_vm_clear_freed - clear freed BOs in the PT
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @fence: optional resulting fence (unchanged if no work needed to be done
 * or if an error occurred)
 *
 * Make sure all freed BOs are cleared in the PT.
 * PTs have to be reserved and mutex must be locked!
 *
 * Returns:
 * 0 for success.
 *
 */
int amdgpu_vm_clear_freed(struct amdgpu_device *adev,
			  struct amdgpu_vm *vm,
			  struct dma_fence **fence)
{
	struct amdgpu_bo_va_mapping *mapping;
	struct dma_fence *f = NULL;
	struct amdgpu_sync sync;
	int r;

	if (list_empty(&vm->freed))
		return 0;

	/*
	 * Implicitly sync to command submissions in the same VM before
	 * unmapping.
	 */
	amdgpu_sync_create(&sync);
	r = amdgpu_sync_resv(adev, &sync, vm->root.bo->tbo.base.resv,
			     AMDGPU_SYNC_EQ_OWNER, vm);
	if (r)
		goto error_free;

	while (!list_empty(&vm->freed)) {
		mapping = list_first_entry(&vm->freed,
			struct amdgpu_bo_va_mapping, list);
		list_del(&mapping->list);

		r = amdgpu_vm_update_range(adev, vm, false, false, true, false,
					   &sync, mapping->start, mapping->last,
					   0, 0, 0, NULL, NULL, &f);
		amdgpu_vm_free_mapping(adev, vm, mapping, f);
		if (r) {
			dma_fence_put(f);
			goto error_free;
		}
	}

	if (fence && f) {
		dma_fence_put(*fence);
		*fence = f;
	} else {
		dma_fence_put(f);
	}

error_free:
	amdgpu_sync_free(&sync);
	return r;

}

/**
 * amdgpu_vm_handle_moved - handle moved BOs in the PT
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @ticket: optional reservation ticket used to reserve the VM
 *
 * Make sure all BOs which are moved are updated in the PTs.
 *
 * Returns:
 * 0 for success.
 *
 * PTs have to be reserved!
 */
int amdgpu_vm_handle_moved(struct amdgpu_device *adev,
			   struct amdgpu_vm *vm,
			   struct ww_acquire_ctx *ticket)
{
	struct amdgpu_bo_va *bo_va, *tmp;
	struct dma_resv *resv;
	struct amdgpu_bo *bo;
	bool clear, unlock;
	int r;

	list_for_each_entry_safe(bo_va, tmp, &vm->always_valid.needs_update,
				 base.vm_status) {
		/* Per VM BOs never need to bo cleared in the page tables */
		r = amdgpu_vm_bo_update(adev, bo_va, false);
		if (r)
			return r;
	}

	spin_lock(&vm->individual_lock);
	while (!list_empty(&vm->individual.needs_update)) {
		bo_va = list_first_entry(&vm->individual.needs_update,
					 typeof(*bo_va), base.vm_status);
		bo = bo_va->base.bo;
		resv = bo->tbo.base.resv;
		spin_unlock(&vm->individual_lock);

		/* Try to reserve the BO to avoid clearing its ptes */
		if (!adev->debug_vm && !amdgpu_ttm_tt_get_usermm(bo->tbo.ttm) &&
		    dma_resv_trylock(resv)) {
			clear = false;
			unlock = true;
		/* The caller is already holding the reservation lock */
		} else if (ticket && dma_resv_locking_ctx(resv) == ticket) {
			clear = false;
			unlock = false;
		/* Somebody else is using the BO right now */
		} else {
			clear = true;
			unlock = false;
		}

		r = amdgpu_vm_bo_update(adev, bo_va, clear);

		if (unlock)
			dma_resv_unlock(resv);
		if (r)
			return r;

		/* Remember evicted DMABuf imports in compute VMs for later
		 * validation
		 */
		if (vm->is_compute_context &&
		    drm_gem_is_imported(&bo_va->base.bo->tbo.base) &&
		    (!bo_va->base.bo->tbo.resource ||
		     bo_va->base.bo->tbo.resource->mem_type == TTM_PL_SYSTEM))
			amdgpu_vm_bo_evicted(&bo_va->base);

		spin_lock(&vm->individual_lock);
	}
	spin_unlock(&vm->individual_lock);

	return 0;
}

/**
 * amdgpu_vm_flush_compute_tlb - Flush TLB on compute VM
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @flush_type: flush type
 * @xcc_mask: mask of XCCs that belong to the compute partition in need of a TLB flush.
 *
 * Flush TLB if needed for a compute VM.
 *
 * Returns:
 * 0 for success.
 */
int amdgpu_vm_flush_compute_tlb(struct amdgpu_device *adev,
				struct amdgpu_vm *vm,
				uint32_t flush_type,
				uint32_t xcc_mask)
{
	uint64_t tlb_seq = amdgpu_vm_tlb_seq(vm);
	bool all_hub = false;
	int xcc = 0, r = 0;

	WARN_ON_ONCE(!vm->is_compute_context);

	/*
	 * It can be that we race and lose here, but that is extremely unlikely
	 * and the worst thing which could happen is that we flush the changes
	 * into the TLB once more which is harmless.
	 */
	if (atomic64_xchg(&vm->kfd_last_flushed_seq, tlb_seq) == tlb_seq)
		return 0;

	if (adev->family == AMDGPU_FAMILY_AI ||
	    adev->family == AMDGPU_FAMILY_RV)
		all_hub = true;

	for_each_inst(xcc, xcc_mask) {
		r = amdgpu_gmc_flush_gpu_tlb_pasid(adev, vm->pasid, flush_type,
						   all_hub, xcc);
		if (r)
			break;
	}
	return r;
}

/**
 * amdgpu_vm_bo_add - add a bo to a specific vm
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @bo: amdgpu buffer object
 *
 * Add @bo into the requested vm.
 * Add @bo to the list of bos associated with the vm
 *
 * Returns:
 * Newly added bo_va or NULL for failure
 *
 * Object has to be reserved!
 */
struct amdgpu_bo_va *amdgpu_vm_bo_add(struct amdgpu_device *adev,
				      struct amdgpu_vm *vm,
				      struct amdgpu_bo *bo)
{
	struct amdgpu_bo_va *bo_va;

	amdgpu_vm_assert_locked(vm);

	bo_va = kzalloc_obj(struct amdgpu_bo_va);
	if (bo_va == NULL) {
		return NULL;
	}
	amdgpu_vm_bo_base_init(&bo_va->base, vm, bo);

	bo_va->ref_count = 1;
	bo_va->last_pt_update = dma_fence_get_stub();
	INIT_LIST_HEAD(&bo_va->valids);
	INIT_LIST_HEAD(&bo_va->invalids);

	if (!bo)
		return bo_va;

	dma_resv_assert_held(bo->tbo.base.resv);
	if (amdgpu_dmabuf_is_xgmi_accessible(adev, bo)) {
		bo_va->is_xgmi = true;
		/* Power up XGMI if it can be potentially used */
		amdgpu_xgmi_set_pstate(adev, AMDGPU_XGMI_PSTATE_MAX_VEGA20);
	}

	return bo_va;
}


/**
 * amdgpu_vm_bo_insert_map - insert a new mapping
 *
 * @adev: amdgpu_device pointer
 * @bo_va: bo_va to store the address
 * @mapping: the mapping to insert
 *
 * Insert a new mapping into all structures.
 */
static void amdgpu_vm_bo_insert_map(struct amdgpu_device *adev,
				    struct amdgpu_bo_va *bo_va,
				    struct amdgpu_bo_va_mapping *mapping)
{
	struct amdgpu_vm *vm = bo_va->base.vm;
	struct amdgpu_bo *bo = bo_va->base.bo;

	mapping->bo_va = bo_va;
	list_add(&mapping->list, &bo_va->invalids);
	amdgpu_vm_it_insert(mapping, &vm->va);

	if (mapping->flags & AMDGPU_VM_PAGE_PRT)
		amdgpu_vm_prt_get(adev);

	if (amdgpu_vm_is_bo_always_valid(vm, bo) && !bo_va->base.moved)
		amdgpu_vm_bo_needs_update(&bo_va->base);

	trace_amdgpu_vm_bo_map(bo_va, mapping);
}

/* Validate operation parameters to prevent potential abuse */
static int amdgpu_vm_verify_parameters(struct amdgpu_device *adev,
					  struct amdgpu_bo *bo,
					  uint64_t saddr,
					  uint64_t offset,
					  uint64_t size)
{
	uint64_t tmp, lpfn;

	if (saddr & AMDGPU_GPU_PAGE_MASK
	    || offset & AMDGPU_GPU_PAGE_MASK
	    || size & AMDGPU_GPU_PAGE_MASK)
		return -EINVAL;

	if (check_add_overflow(saddr, size, &tmp)
	    || check_add_overflow(offset, size, &tmp)
	    || size == 0 /* which also leads to end < begin */)
		return -EINVAL;

	/* make sure object fit at this offset */
	if (bo && offset + size > amdgpu_bo_size(bo))
		return -EINVAL;

	/* Ensure last pfn not exceed max_pfn */
	lpfn = (saddr + size - 1) >> AMDGPU_GPU_PAGE_SHIFT;
	if (lpfn >= adev->vm_manager.max_pfn)
		return -EINVAL;

	return 0;
}

/**
 * amdgpu_vm_bo_map - map bo inside a vm
 *
 * @adev: amdgpu_device pointer
 * @bo_va: bo_va to store the address
 * @saddr: where to map the BO
 * @offset: requested offset in the BO
 * @size: BO size in bytes
 * @flags: attributes of pages (read/write/valid/etc.)
 *
 * Add a mapping of the BO at the specefied addr into the VM.
 *
 * Returns:
 * 0 for success, error for failure.
 *
 * Object has to be reserved and unreserved outside!
 */
int amdgpu_vm_bo_map(struct amdgpu_device *adev,
		     struct amdgpu_bo_va *bo_va,
		     uint64_t saddr, uint64_t offset,
		     uint64_t size, uint32_t flags)
{
	struct amdgpu_bo_va_mapping *mapping, *tmp;
	struct amdgpu_bo *bo = bo_va->base.bo;
	struct amdgpu_vm *vm = bo_va->base.vm;
	uint64_t eaddr;
	int r;

	r = amdgpu_vm_verify_parameters(adev, bo, saddr, offset, size);
	if (r)
		return r;

	saddr /= AMDGPU_GPU_PAGE_SIZE;
	eaddr = saddr + (size - 1) / AMDGPU_GPU_PAGE_SIZE;

	tmp = amdgpu_vm_it_iter_first(&vm->va, saddr, eaddr);
	if (tmp) {
		/* bo and tmp overlap, invalid addr */
		dev_err(adev->dev, "bo %p va 0x%010Lx-0x%010Lx conflict with "
			"0x%010Lx-0x%010Lx\n", bo, saddr, eaddr,
			tmp->start, tmp->last + 1);
		return -EINVAL;
	}

	mapping = kmalloc_obj(*mapping);
	if (!mapping)
		return -ENOMEM;

	mapping->start = saddr;
	mapping->last = eaddr;
	mapping->offset = offset;
	mapping->flags = flags;

	amdgpu_vm_bo_insert_map(adev, bo_va, mapping);

	return 0;
}

/**
 * amdgpu_vm_bo_replace_map - map bo inside a vm, replacing existing mappings
 *
 * @adev: amdgpu_device pointer
 * @bo_va: bo_va to store the address
 * @saddr: where to map the BO
 * @offset: requested offset in the BO
 * @size: BO size in bytes
 * @flags: attributes of pages (read/write/valid/etc.)
 *
 * Add a mapping of the BO at the specefied addr into the VM. Replace existing
 * mappings as we do so.
 *
 * Returns:
 * 0 for success, error for failure.
 *
 * Object has to be reserved and unreserved outside!
 */
int amdgpu_vm_bo_replace_map(struct amdgpu_device *adev,
			     struct amdgpu_bo_va *bo_va,
			     uint64_t saddr, uint64_t offset,
			     uint64_t size, uint32_t flags)
{
	struct amdgpu_bo_va_mapping *mapping;
	struct amdgpu_bo *bo = bo_va->base.bo;
	uint64_t eaddr;
	int r;

	r = amdgpu_vm_verify_parameters(adev, bo, saddr, offset, size);
	if (r)
		return r;

	/* Allocate all the needed memory */
	mapping = kmalloc_obj(*mapping);
	if (!mapping)
		return -ENOMEM;

	r = amdgpu_vm_bo_clear_mappings(adev, bo_va->base.vm, saddr, size);
	if (r) {
		kfree(mapping);
		return r;
	}

	saddr /= AMDGPU_GPU_PAGE_SIZE;
	eaddr = saddr + (size - 1) / AMDGPU_GPU_PAGE_SIZE;

	mapping->start = saddr;
	mapping->last = eaddr;
	mapping->offset = offset;
	mapping->flags = flags;

	amdgpu_vm_bo_insert_map(adev, bo_va, mapping);

	return 0;
}

/**
 * amdgpu_vm_bo_unmap - remove bo mapping from vm
 *
 * @adev: amdgpu_device pointer
 * @bo_va: bo_va to remove the address from
 * @saddr: where to the BO is mapped
 *
 * Remove a mapping of the BO at the specefied addr from the VM.
 *
 * Returns:
 * 0 for success, error for failure.
 *
 * Object has to be reserved and unreserved outside!
 */
int amdgpu_vm_bo_unmap(struct amdgpu_device *adev,
		       struct amdgpu_bo_va *bo_va,
		       uint64_t saddr)
{
	struct amdgpu_bo_va_mapping *mapping;
	struct amdgpu_vm *vm = bo_va->base.vm;
	bool valid = true;

	saddr /= AMDGPU_GPU_PAGE_SIZE;

	list_for_each_entry(mapping, &bo_va->valids, list) {
		if (mapping->start == saddr)
			break;
	}

	if (&mapping->list == &bo_va->valids) {
		valid = false;

		list_for_each_entry(mapping, &bo_va->invalids, list) {
			if (mapping->start == saddr)
				break;
		}

		if (&mapping->list == &bo_va->invalids)
			return -ENOENT;
	}

	/* It's unlikely to happen that the mapping userq hasn't been idled
	 * during user requests GEM unmap IOCTL except for forcing the unmap
	 * from user space.
	 */
	if (unlikely(bo_va->userq_va_mapped))
		amdgpu_userq_gem_va_unmap_validate(adev, mapping);

	list_del(&mapping->list);
	amdgpu_vm_it_remove(mapping, &vm->va);
	mapping->bo_va = NULL;
	trace_amdgpu_vm_bo_unmap(bo_va, mapping);

	if (valid)
		list_add(&mapping->list, &vm->freed);
	else
		amdgpu_vm_free_mapping(adev, vm, mapping,
				       bo_va->last_pt_update);

	return 0;
}

/**
 * amdgpu_vm_bo_clear_mappings - remove all mappings in a specific range
 *
 * @adev: amdgpu_device pointer
 * @vm: VM structure to use
 * @saddr: start of the range
 * @size: size of the range
 *
 * Remove all mappings in a range, split them as appropriate.
 *
 * Returns:
 * 0 for success, error for failure.
 */
int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev,
				struct amdgpu_vm *vm,
				uint64_t saddr, uint64_t size)
{
	struct amdgpu_bo_va_mapping *before, *after, *tmp, *next;
	LIST_HEAD(removed);
	uint64_t eaddr;
	int r;

	r = amdgpu_vm_verify_parameters(adev, NULL, saddr, 0, size);
	if (r)
		return r;

	saddr /= AMDGPU_GPU_PAGE_SIZE;
	eaddr = saddr + (size - 1) / AMDGPU_GPU_PAGE_SIZE;

	/* Allocate all the needed memory */
	before = kzalloc_obj(*before);
	if (!before)
		return -ENOMEM;
	INIT_LIST_HEAD(&before->list);

	after = kzalloc_obj(*after);
	if (!after) {
		kfree(before);
		return -ENOMEM;
	}
	INIT_LIST_HEAD(&after->list);

	/* Now gather all removed mappings */
	tmp = amdgpu_vm_it_iter_first(&vm->va, saddr, eaddr);
	while (tmp) {
		/* Remember mapping split at the start */
		if (tmp->start < saddr) {
			before->start = tmp->start;
			before->last = saddr - 1;
			before->offset = tmp->offset;
			before->flags = tmp->flags;
			before->bo_va = tmp->bo_va;
			list_add(&before->list, &tmp->bo_va->invalids);
		}

		/* Remember mapping split at the end */
		if (tmp->last > eaddr) {
			after->start = eaddr + 1;
			after->last = tmp->last;
			after->offset = tmp->offset;
			after->offset += (after->start - tmp->start) << AMDGPU_GPU_PAGE_SHIFT;
			after->flags = tmp->flags;
			after->bo_va = tmp->bo_va;
			list_add(&after->list, &tmp->bo_va->invalids);
		}

		list_del(&tmp->list);
		list_add(&tmp->list, &removed);

		tmp = amdgpu_vm_it_iter_next(tmp, saddr, eaddr);
	}

	/* And free them up */
	list_for_each_entry_safe(tmp, next, &removed, list) {
		amdgpu_vm_it_remove(tmp, &vm->va);
		list_del(&tmp->list);

		if (tmp->start < saddr)
		    tmp->start = saddr;
		if (tmp->last > eaddr)
		    tmp->last = eaddr;

		tmp->bo_va = NULL;
		list_add(&tmp->list, &vm->freed);
		trace_amdgpu_vm_bo_unmap(NULL, tmp);
	}

	/* Insert partial mapping before the range */
	if (!list_empty(&before->list)) {
		struct amdgpu_bo *bo = before->bo_va->base.bo;

		amdgpu_vm_it_insert(before, &vm->va);
		if (before->flags & AMDGPU_VM_PAGE_PRT)
			amdgpu_vm_prt_get(adev);

		if (amdgpu_vm_is_bo_always_valid(vm, bo) &&
		    !before->bo_va->base.moved)
			amdgpu_vm_bo_needs_update(&before->bo_va->base);
	} else {
		kfree(before);
	}

	/* Insert partial mapping after the range */
	if (!list_empty(&after->list)) {
		struct amdgpu_bo *bo = after->bo_va->base.bo;

		amdgpu_vm_it_insert(after, &vm->va);
		if (after->flags & AMDGPU_VM_PAGE_PRT)
			amdgpu_vm_prt_get(adev);

		if (amdgpu_vm_is_bo_always_valid(vm, bo) &&
		    !after->bo_va->base.moved)
			amdgpu_vm_bo_needs_update(&after->bo_va->base);
	} else {
		kfree(after);
	}

	return 0;
}

/**
 * amdgpu_vm_bo_lookup_mapping - find mapping by address
 *
 * @vm: the requested VM
 * @addr: the address
 *
 * Find a mapping by it's address.
 *
 * Returns:
 * The amdgpu_bo_va_mapping matching for addr or NULL
 *
 */
struct amdgpu_bo_va_mapping *amdgpu_vm_bo_lookup_mapping(struct amdgpu_vm *vm,
							 uint64_t addr)
{
	return amdgpu_vm_it_iter_first(&vm->va, addr, addr);
}

/**
 * amdgpu_vm_bo_trace_cs - trace all reserved mappings
 *
 * @vm: the requested vm
 * @ticket: CS ticket
 *
 * Trace all mappings of BOs reserved during a command submission.
 */
void amdgpu_vm_bo_trace_cs(struct amdgpu_vm *vm, struct ww_acquire_ctx *ticket)
{
	struct amdgpu_bo_va_mapping *mapping;

	if (!trace_amdgpu_vm_bo_cs_enabled())
		return;

	for (mapping = amdgpu_vm_it_iter_first(&vm->va, 0, U64_MAX); mapping;
	     mapping = amdgpu_vm_it_iter_next(mapping, 0, U64_MAX)) {
		if (mapping->bo_va && mapping->bo_va->base.bo) {
			struct amdgpu_bo *bo;

			bo = mapping->bo_va->base.bo;
			if (dma_resv_locking_ctx(bo->tbo.base.resv) !=
			    ticket)
				continue;
		}

		trace_amdgpu_vm_bo_cs(mapping);
	}
}

/**
 * amdgpu_vm_bo_del - remove a bo from a specific vm
 *
 * @adev: amdgpu_device pointer
 * @bo_va: requested bo_va
 *
 * Remove @bo_va->bo from the requested vm.
 *
 * Object have to be reserved!
 */
void amdgpu_vm_bo_del(struct amdgpu_device *adev,
		      struct amdgpu_bo_va *bo_va)
{
	struct amdgpu_bo_va_mapping *mapping, *next;
	struct amdgpu_bo *bo = bo_va->base.bo;
	struct amdgpu_vm *vm = bo_va->base.vm;
	struct amdgpu_vm_bo_base **base;

	dma_resv_assert_held(vm->root.bo->tbo.base.resv);

	if (bo) {
		dma_resv_assert_held(bo->tbo.base.resv);
		if (amdgpu_vm_is_bo_always_valid(vm, bo))
			ttm_bo_set_bulk_move(&bo->tbo, NULL);

		for (base = &bo_va->base.bo->vm_bo; *base;
		     base = &(*base)->next) {
			if (*base != &bo_va->base)
				continue;

			amdgpu_vm_update_stats(*base, bo->tbo.resource, -1);
			*base = bo_va->base.next;
			break;
		}
	}

	spin_lock(&vm->individual_lock);
	list_del(&bo_va->base.vm_status);
	spin_unlock(&vm->individual_lock);

	list_for_each_entry_safe(mapping, next, &bo_va->valids, list) {
		list_del(&mapping->list);
		amdgpu_vm_it_remove(mapping, &vm->va);
		mapping->bo_va = NULL;
		trace_amdgpu_vm_bo_unmap(bo_va, mapping);
		list_add(&mapping->list, &vm->freed);
	}
	list_for_each_entry_safe(mapping, next, &bo_va->invalids, list) {
		list_del(&mapping->list);
		amdgpu_vm_it_remove(mapping, &vm->va);
		amdgpu_vm_free_mapping(adev, vm, mapping,
				       bo_va->last_pt_update);
	}

	dma_fence_put(bo_va->last_pt_update);

	if (bo && bo_va->is_xgmi)
		amdgpu_xgmi_set_pstate(adev, AMDGPU_XGMI_PSTATE_MIN);

	kfree(bo_va);
}

/**
 * amdgpu_vm_evictable - check if we can evict a VM
 *
 * @bo: A page table of the VM.
 *
 * Check if it is possible to evict a VM.
 */
bool amdgpu_vm_evictable(struct amdgpu_bo *bo)
{
	struct amdgpu_vm_bo_base *bo_base = bo->vm_bo;

	/* Page tables of a destroyed VM can go away immediately */
	if (!bo_base || !bo_base->vm)
		return true;

	/* Don't evict VM page tables while they are busy */
	if (!dma_resv_test_signaled(bo->tbo.base.resv, DMA_RESV_USAGE_BOOKKEEP))
		return false;

	/* Try to block ongoing updates */
	if (!amdgpu_vm_eviction_trylock(bo_base->vm))
		return false;

	/* Don't evict VM page tables while they are updated */
	if (!dma_fence_is_signaled(bo_base->vm->last_unlocked)) {
		amdgpu_vm_eviction_unlock(bo_base->vm);
		return false;
	}

	bo_base->vm->evicting = true;
	amdgpu_vm_eviction_unlock(bo_base->vm);
	return true;
}

/**
 * amdgpu_vm_bo_invalidate - mark the bo as invalid
 *
 * @bo: amdgpu buffer object
 * @evicted: is the BO evicted
 *
 * Mark @bo as invalid.
 */
void amdgpu_vm_bo_invalidate(struct amdgpu_bo *bo, bool evicted)
{
	struct amdgpu_vm_bo_base *bo_base;

	for (bo_base = bo->vm_bo; bo_base; bo_base = bo_base->next) {
		struct amdgpu_vm *vm = bo_base->vm;

		if (evicted && amdgpu_vm_is_bo_always_valid(vm, bo)) {
			amdgpu_vm_bo_evicted(bo_base);
			continue;
		}

		if (bo_base->moved)
			continue;
		bo_base->moved = true;
		amdgpu_vm_bo_needs_update(bo_base);
	}
}

/**
 * amdgpu_vm_bo_move - handle BO move
 *
 * @bo: amdgpu buffer object
 * @new_mem: the new placement of the BO move
 * @evicted: is the BO evicted
 *
 * Update the memory stats for the new placement and mark @bo as invalid.
 */
void amdgpu_vm_bo_move(struct amdgpu_bo *bo, struct ttm_resource *new_mem,
		       bool evicted)
{
	struct amdgpu_vm_bo_base *bo_base;

	for (bo_base = bo->vm_bo; bo_base; bo_base = bo_base->next) {
		struct amdgpu_vm *vm = bo_base->vm;

		spin_lock(&vm->stats_lock);
		amdgpu_vm_update_stats_locked(bo_base, bo->tbo.resource, -1);
		amdgpu_vm_update_stats_locked(bo_base, new_mem, +1);
		spin_unlock(&vm->stats_lock);
	}

	amdgpu_vm_bo_invalidate(bo, evicted);
}

/**
 * amdgpu_vm_get_block_size - calculate VM page table size as power of two
 *
 * @vm_size: VM size
 *
 * Returns:
 * VM page table as power of two
 */
static uint32_t amdgpu_vm_get_block_size(uint64_t vm_size)
{
	/* Total bits covered by PD + PTs */
	unsigned bits = ilog2(vm_size) + 18;

	/* Make sure the PD is 4K in size up to 8GB address space.
	   Above that split equal between PD and PTs */
	if (vm_size <= 8)
		return (bits - 9);
	else
		return ((bits + 3) / 2);
}

/**
 * amdgpu_vm_adjust_size - adjust vm size, block size and fragment size
 *
 * @adev: amdgpu_device pointer
 * @min_vm_size: the minimum vm size in GB if it's set auto
 * @fragment_size_default: Default PTE fragment size
 * @max_level: max VMPT level
 * @max_bits: max address space size in bits
 *
 */
void amdgpu_vm_adjust_size(struct amdgpu_device *adev, uint32_t min_vm_size,
			   uint32_t fragment_size_default, unsigned max_level,
			   unsigned max_bits)
{
	unsigned int max_size = 1 << (max_bits - 30);
	unsigned int vm_size;
	uint64_t tmp;

	/* adjust vm size first */
	if (amdgpu_vm_size != -1) {
		vm_size = amdgpu_vm_size;
		if (vm_size > max_size) {
			dev_warn(adev->dev, "VM size (%d) too large, max is %u GB\n",
				 amdgpu_vm_size, max_size);
			vm_size = max_size;
		}
	} else {
		struct sysinfo si;
		unsigned int phys_ram_gb;

		/* Optimal VM size depends on the amount of physical
		 * RAM available. Underlying requirements and
		 * assumptions:
		 *
		 *  - Need to map system memory and VRAM from all GPUs
		 *     - VRAM from other GPUs not known here
		 *     - Assume VRAM <= system memory
		 *  - On GFX8 and older, VM space can be segmented for
		 *    different MTYPEs
		 *  - Need to allow room for fragmentation, guard pages etc.
		 *
		 * This adds up to a rough guess of system memory x3.
		 * Round up to power of two to maximize the available
		 * VM size with the given page table size.
		 */
		si_meminfo(&si);
		phys_ram_gb = ((uint64_t)si.totalram * si.mem_unit +
			       (1 << 30) - 1) >> 30;
		vm_size = roundup_pow_of_two(
			clamp(phys_ram_gb * 3, min_vm_size, max_size));
	}

	adev->vm_manager.max_pfn = (uint64_t)vm_size << 18;
	adev->vm_manager.max_level = max_level;

	tmp = roundup_pow_of_two(adev->vm_manager.max_pfn);
	if (amdgpu_vm_block_size != -1)
		tmp >>= amdgpu_vm_block_size - 9;
	tmp = DIV_ROUND_UP(fls64(tmp) - 1, 9) - 1;
	adev->vm_manager.num_level = min_t(unsigned int, max_level, tmp);
	switch (adev->vm_manager.num_level) {
	case 4:
		adev->vm_manager.root_level = AMDGPU_VM_PDB3;
		break;
	case 3:
		adev->vm_manager.root_level = AMDGPU_VM_PDB2;
		break;
	case 2:
		adev->vm_manager.root_level = AMDGPU_VM_PDB1;
		break;
	case 1:
		adev->vm_manager.root_level = AMDGPU_VM_PDB0;
		break;
	default:
		dev_err(adev->dev, "VMPT only supports 2~4+1 levels\n");
	}
	/* block size depends on vm size and hw setup*/
	if (amdgpu_vm_block_size != -1)
		adev->vm_manager.block_size =
			min((unsigned)amdgpu_vm_block_size, max_bits
			    - AMDGPU_GPU_PAGE_SHIFT
			    - 9 * adev->vm_manager.num_level);
	else if (adev->vm_manager.num_level > 1)
		adev->vm_manager.block_size = 9;
	else
		adev->vm_manager.block_size = amdgpu_vm_get_block_size(tmp);

	if (amdgpu_vm_fragment_size == -1)
		adev->vm_manager.fragment_size = fragment_size_default;
	else
		adev->vm_manager.fragment_size = amdgpu_vm_fragment_size;

	dev_info(
		adev->dev,
		"vm size is %u GB, %u levels, block size is %u-bit, fragment size is %u-bit\n",
		vm_size, adev->vm_manager.num_level + 1,
		adev->vm_manager.block_size, adev->vm_manager.fragment_size);
}

/**
 * amdgpu_vm_wait_idle - wait for the VM to become idle
 *
 * @vm: VM object to wait for
 * @timeout: timeout to wait for VM to become idle
 */
long amdgpu_vm_wait_idle(struct amdgpu_vm *vm, long timeout)
{
	timeout = drm_sched_entity_flush(&vm->immediate, timeout);
	if (timeout <= 0)
		return timeout;

	return drm_sched_entity_flush(&vm->delayed, timeout);
}

static void amdgpu_vm_destroy_task_info(struct kref *kref)
{
	struct amdgpu_task_info *ti = container_of(kref, struct amdgpu_task_info, refcount);

	kfree(ti);
}

/**
 * amdgpu_vm_put_task_info - reference down the vm task_info ptr
 *
 * @task_info: task_info struct under discussion.
 *
 * frees the vm task_info ptr at the last put
 */
void amdgpu_vm_put_task_info(struct amdgpu_task_info *task_info)
{
	if (task_info)
		kref_put(&task_info->refcount, amdgpu_vm_destroy_task_info);
}

/**
 * amdgpu_vm_get_task_info_vm - Extracts task info for a vm.
 *
 * @vm: VM to get info from
 *
 * Returns the reference counted task_info structure, which must be
 * referenced down with amdgpu_vm_put_task_info.
 */
struct amdgpu_task_info *
amdgpu_vm_get_task_info_vm(struct amdgpu_vm *vm)
{
	struct amdgpu_task_info *ti = NULL;

	if (vm) {
		ti = vm->task_info;
		kref_get(&vm->task_info->refcount);
	}

	return ti;
}

/**
 * amdgpu_vm_get_task_info_pasid - Extracts task info for a PASID.
 *
 * @adev: drm device pointer
 * @pasid: PASID identifier for VM
 *
 * Returns the reference counted task_info structure, which must be
 * referenced down with amdgpu_vm_put_task_info.
 */
struct amdgpu_task_info *
amdgpu_vm_get_task_info_pasid(struct amdgpu_device *adev, u32 pasid)
{
	struct amdgpu_fpriv *fpriv;
	struct amdgpu_task_info *ti;
	struct amdgpu_vm *vm;
	unsigned long flags;

	amdgpu_pasid_lock(&flags);
	fpriv = amdgpu_pasid_get_fpriv_locked(pasid);
	vm = fpriv ? &fpriv->vm : NULL;
	ti = amdgpu_vm_get_task_info_vm(vm);
	amdgpu_pasid_unlock(flags);

	return ti;
}

static int amdgpu_vm_create_task_info(struct amdgpu_vm *vm)
{
	vm->task_info = kzalloc_obj(struct amdgpu_task_info);
	if (!vm->task_info)
		return -ENOMEM;

	kref_init(&vm->task_info->refcount);
	return 0;
}

/**
 * amdgpu_vm_set_task_info - Sets VMs task info.
 *
 * @vm: vm for which to set the info
 */
void amdgpu_vm_set_task_info(struct amdgpu_vm *vm)
{
	if (!vm->task_info)
		return;

	if (vm->task_info->task.pid == current->pid)
		return;

	vm->task_info->task.pid = current->pid;
	get_task_comm(vm->task_info->task.comm, current);

	vm->task_info->tgid = current->tgid;
	get_task_comm(vm->task_info->process_name, current->group_leader);
}

/**
 * amdgpu_vm_init - initialize a vm instance
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @xcp_id: GPU partition selection id
 *
 * Init @vm fields.
 *
 * Returns:
 * 0 for success, error for failure.
 */
int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
		   int32_t xcp_id)
{
	struct amdgpu_bo *root_bo;
	struct amdgpu_bo_vm *root;
	int r, i;

	vm->va = RB_ROOT_CACHED;
	for (i = 0; i < AMDGPU_MAX_VMHUBS; i++)
		vm->reserved_vmid[i] = NULL;

	amdgpu_vm_bo_status_init(&vm->kernel);
	amdgpu_vm_bo_status_init(&vm->always_valid);
	spin_lock_init(&vm->individual_lock);
	amdgpu_vm_bo_status_init(&vm->individual);
	INIT_LIST_HEAD(&vm->freed);
	INIT_KFIFO(vm->faults);
	spin_lock_init(&vm->stats_lock);

	r = amdgpu_vm_init_entities(adev, vm);
	if (r)
		return r;

	ttm_lru_bulk_move_init(&vm->lru_bulk_move);

	vm->is_compute_context = false;
	vm->need_tlb_fence = amdgpu_userq_enabled(&adev->ddev);

	vm->use_cpu_for_update = !!(adev->vm_manager.vm_update_mode &
				    AMDGPU_VM_USE_CPU_FOR_GFX);

	dev_dbg(adev->dev, "VM update mode is %s\n",
		vm->use_cpu_for_update ? "CPU" : "SDMA");
	WARN_ONCE((vm->use_cpu_for_update &&
		   !amdgpu_gmc_vram_full_visible(&adev->gmc)),
		  "CPU update of VM recommended only for large BAR system\n");

	if (vm->use_cpu_for_update)
		vm->update_funcs = &amdgpu_vm_cpu_funcs;
	else
		vm->update_funcs = &amdgpu_vm_sdma_funcs;

	vm->last_update = dma_fence_get_stub();
	vm->last_unlocked = dma_fence_get_stub();
	vm->last_tlb_flush = dma_fence_get_stub();
	vm->generation = amdgpu_vm_generation(adev, NULL);

	mutex_init(&vm->eviction_lock);
	vm->evicting = false;
	vm->tlb_fence_context = dma_fence_context_alloc(1);

	r = amdgpu_vm_pt_create(adev, vm, adev->vm_manager.root_level,
				false, &root, xcp_id);
	if (r)
		goto error_free_delayed;

	root_bo = amdgpu_bo_ref(&root->bo);
	r = amdgpu_bo_reserve(root_bo, true);
	if (r) {
		amdgpu_bo_unref(&root_bo);
		goto error_free_delayed;
	}

	amdgpu_vm_bo_base_init(&vm->root, vm, root_bo);
	r = dma_resv_reserve_fences(root_bo->tbo.base.resv, 1);
	if (r)
		goto error_free_root;

	r = amdgpu_vm_pt_clear(adev, vm, root, false);
	if (r)
		goto error_free_root;

	r = amdgpu_vm_create_task_info(vm);
	if (r)
		dev_dbg(adev->dev, "Failed to create task info for VM\n");

	amdgpu_bo_unreserve(vm->root.bo);
	amdgpu_bo_unref(&root_bo);

	return 0;

error_free_root:
	amdgpu_vm_pt_free_root(adev, vm);
	amdgpu_bo_unreserve(vm->root.bo);
	amdgpu_bo_unref(&root_bo);

error_free_delayed:
	dma_fence_put(vm->last_tlb_flush);
	dma_fence_put(vm->last_unlocked);
	ttm_lru_bulk_move_fini(&adev->mman.bdev, &vm->lru_bulk_move);
	amdgpu_vm_fini_entities(vm);

	return r;
}

/**
 * amdgpu_vm_make_compute - Turn a GFX VM into a compute VM
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 *
 * This only works on GFX VMs that don't have any BOs added and no
 * page tables allocated yet.
 *
 * Changes the following VM parameters:
 * - use_cpu_for_update
 * - pte_supports_ats
 *
 * Reinitializes the page directory to reflect the changed ATS
 * setting.
 *
 * Returns:
 * 0 for success, -errno for errors.
 */
int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm)
{
	int r;

	r = amdgpu_bo_reserve(vm->root.bo, true);
	if (r)
		return r;

	/* Update VM state */
	vm->use_cpu_for_update = !!(adev->vm_manager.vm_update_mode &
				    AMDGPU_VM_USE_CPU_FOR_COMPUTE);
	dev_dbg(adev->dev, "VM update mode is %s\n",
		vm->use_cpu_for_update ? "CPU" : "SDMA");
	WARN_ONCE((vm->use_cpu_for_update &&
		   !amdgpu_gmc_vram_full_visible(&adev->gmc)),
		  "CPU update of VM recommended only for large BAR system\n");

	if (vm->use_cpu_for_update) {
		/* Sync with last SDMA update/clear before switching to CPU */
		r = amdgpu_bo_sync_wait(vm->root.bo,
					AMDGPU_FENCE_OWNER_UNDEFINED, true);
		if (r)
			goto unreserve_bo;

		vm->update_funcs = &amdgpu_vm_cpu_funcs;
		r = amdgpu_vm_pt_map_tables(adev, vm);
		if (r)
			goto unreserve_bo;

	} else {
		vm->update_funcs = &amdgpu_vm_sdma_funcs;
	}

	dma_fence_put(vm->last_update);
	vm->last_update = dma_fence_get_stub();
	vm->is_compute_context = true;
	vm->need_tlb_fence = true;

unreserve_bo:
	amdgpu_bo_unreserve(vm->root.bo);
	return r;
}

static int amdgpu_vm_stats_is_zero(struct amdgpu_vm *vm)
{
	for (int i = 0; i < __AMDGPU_PL_NUM; ++i) {
		if (!(drm_memory_stats_is_zero(&vm->stats[i].drm) &&
		      vm->stats[i].evicted == 0))
			return false;
	}
	return true;
}

/**
 * amdgpu_vm_fini - tear down a vm instance
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 *
 * Tear down @vm.
 * Unbind the VM and remove all bos from the vm bo list
 */
void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm)
{
	struct amdgpu_bo_va_mapping *mapping, *tmp;
	bool prt_fini_needed = !!adev->gmc.gmc_funcs->set_prt;
	struct amdgpu_bo *root;
	unsigned long flags;
	int i;

	amdgpu_amdkfd_gpuvm_destroy_cb(adev, vm);

	root = amdgpu_bo_ref(vm->root.bo);
	amdgpu_bo_reserve(root, true);
	dma_fence_wait(vm->last_unlocked, false);
	dma_fence_put(vm->last_unlocked);
	dma_fence_wait(vm->last_tlb_flush, false);
	/* Make sure that all fence callbacks have completed */
	dma_fence_lock_irqsave(vm->last_tlb_flush, flags);
	dma_fence_unlock_irqrestore(vm->last_tlb_flush, flags);
	dma_fence_put(vm->last_tlb_flush);

	list_for_each_entry_safe(mapping, tmp, &vm->freed, list) {
		if (mapping->flags & AMDGPU_VM_PAGE_PRT && prt_fini_needed) {
			amdgpu_vm_prt_fini(adev, vm);
			prt_fini_needed = false;
		}

		list_del(&mapping->list);
		amdgpu_vm_free_mapping(adev, vm, mapping, NULL);
	}

	amdgpu_vm_pt_free_root(adev, vm);
	amdgpu_bo_unreserve(root);
	amdgpu_bo_unref(&root);
	WARN_ON(vm->root.bo);

	amdgpu_vm_fini_entities(vm);

	if (!RB_EMPTY_ROOT(&vm->va.rb_root)) {
		dev_err(adev->dev, "still active bo inside vm\n");
	}
	rbtree_postorder_for_each_entry_safe(mapping, tmp,
					     &vm->va.rb_root, rb) {
		/* Don't remove the mapping here, we don't want to trigger a
		 * rebalance and the tree is about to be destroyed anyway.
		 */
		list_del(&mapping->list);
		kfree(mapping);
	}

	dma_fence_put(vm->last_update);

	for (i = 0; i < AMDGPU_MAX_VMHUBS; i++) {
		amdgpu_vmid_free_reserved(adev, vm, i);
	}

	ttm_lru_bulk_move_fini(&adev->mman.bdev, &vm->lru_bulk_move);

	if (!amdgpu_vm_stats_is_zero(vm)) {
		struct amdgpu_task_info *ti = vm->task_info;

		dev_warn(adev->dev,
			 "VM memory stats for proc %s(%d) task %s(%d) is non-zero when fini\n",
			 ti->process_name, ti->task.pid, ti->task.comm, ti->tgid);
	}

	amdgpu_vm_put_task_info(vm->task_info);
}

/**
 * amdgpu_vm_manager_init - init the VM manager
 *
 * @adev: amdgpu_device pointer
 *
 * Initialize the VM manager structures
 */
void amdgpu_vm_manager_init(struct amdgpu_device *adev)
{
	/* Concurrent flushes are only possible starting with Vega10 and
	 * are broken on Navi10 and Navi14.
	 */
	adev->vm_manager.concurrent_flush = !(adev->asic_type < CHIP_VEGA10 ||
					      adev->asic_type == CHIP_NAVI10 ||
					      adev->asic_type == CHIP_NAVI14);
	amdgpu_vmid_mgr_init(adev);

	spin_lock_init(&adev->vm_manager.prt_lock);
	atomic_set(&adev->vm_manager.num_prt_users, 0);

	/* If not overridden by the user, by default, only in large BAR systems
	 * Compute VM tables will be updated by CPU
	 */
#ifdef CONFIG_X86_64
	if (amdgpu_vm_update_mode == -1) {
		/* For asic with VF MMIO access protection
		 * avoid using CPU for VM table updates
		 */
		if (amdgpu_gmc_vram_full_visible(&adev->gmc) &&
		    !amdgpu_sriov_vf_mmio_access_protection(adev))
			adev->vm_manager.vm_update_mode =
				AMDGPU_VM_USE_CPU_FOR_COMPUTE;
		else
			adev->vm_manager.vm_update_mode = 0;
	} else
		adev->vm_manager.vm_update_mode = amdgpu_vm_update_mode;
#else
	adev->vm_manager.vm_update_mode = 0;
#endif
}

/**
 * amdgpu_vm_manager_fini - cleanup VM manager
 *
 * @adev: amdgpu_device pointer
 *
 * Cleanup the VM manager and free resources.
 */
void amdgpu_vm_manager_fini(struct amdgpu_device *adev)
{
	amdgpu_vmid_mgr_fini(adev);
	amdgpu_pasid_mgr_cleanup();
}

/**
 * amdgpu_vm_ioctl - Manages VMID reservation for vm hubs.
 *
 * @dev: drm device pointer
 * @data: drm_amdgpu_vm
 * @filp: drm file pointer
 *
 * Returns:
 * 0 for success, -errno for errors.
 */
int amdgpu_vm_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
{
	union drm_amdgpu_vm *args = data;
	struct amdgpu_device *adev = drm_to_adev(dev);
	struct amdgpu_fpriv *fpriv = filp->driver_priv;
	struct amdgpu_vm *vm = &fpriv->vm;

	/* No valid flags defined yet */
	if (args->in.flags)
		return -EINVAL;

	switch (args->in.op) {
	case AMDGPU_VM_OP_RESERVE_VMID:
		/* We only have requirement to reserve vmid from gfxhub */
		return amdgpu_vmid_alloc_reserved(adev, vm, AMDGPU_GFXHUB(0));
	case AMDGPU_VM_OP_UNRESERVE_VMID:
		amdgpu_vmid_free_reserved(adev, vm, AMDGPU_GFXHUB(0));
		break;
	default:
		return -EINVAL;
	}

	return 0;
}

/**
 * amdgpu_vm_lock_by_pasid - look up a VM by PASID and lock its root PD
 * @adev: amdgpu device pointer
 * @pasid: PASID of the VM
 * @exec: drm_exec context to lock the root PD in
 *
 * Must be called from within a drm_exec_until_all_locked() loop; the caller
 * runs drm_exec_retry_on_contention() afterwards. The drm_exec context holds
 * a reference on the root BO until it is finalised.
 *
 * Return: the VM on success, or NULL if the PASID has no VM, the VM is being
 * torn down, or locking the root PD failed.
 */
struct amdgpu_vm *amdgpu_vm_lock_by_pasid(struct amdgpu_device *adev,
					  u32 pasid, struct drm_exec *exec)
{
	unsigned long irqflags;
	struct amdgpu_fpriv *fpriv;
	struct amdgpu_bo *root;
	struct amdgpu_vm *vm;
	int r;

	amdgpu_pasid_lock(&irqflags);
	fpriv = amdgpu_pasid_get_fpriv_locked(pasid);
	vm = fpriv ? &fpriv->vm : NULL;
	root = vm && vm->root.bo ? amdgpu_bo_ref(vm->root.bo) : NULL;
	amdgpu_pasid_unlock(irqflags);

	if (!root)
		return NULL;

	r = drm_exec_lock_obj(exec, &root->tbo.base);
	if (r) {
		amdgpu_bo_unref(&root);
		return NULL;
	}

	/* Double check that the VM still exists */
	amdgpu_pasid_lock(&irqflags);
	fpriv = amdgpu_pasid_get_fpriv_locked(pasid);
	if (!fpriv) {
		vm = NULL;
	} else {
		vm = &fpriv->vm;
		if (vm->root.bo != root)
			vm = NULL;
	}
	amdgpu_pasid_unlock(irqflags);

	if (!vm) {
		drm_exec_unlock_obj(exec, &root->tbo.base);
		amdgpu_bo_unref(&root);
		return NULL;
	}

	/* The drm_exec context holds its own reference on the root BO. */
	amdgpu_bo_unref(&root);

	return vm;
}

/**
 * amdgpu_vm_handle_fault - graceful handling of VM faults.
 * @adev: amdgpu device pointer
 * @pasid: PASID of the VM
 * @ts: Timestamp of the fault
 * @vmid: VMID, only used for GFX 9.4.3.
 * @node_id: Node_id received in IH cookie. Only applicable for
 *           GFX 9.4.3.
 * @addr: Address of the fault
 * @write_fault: true is write fault, false is read fault
 *
 * Try to gracefully handle a VM fault. Return true if the fault was handled and
 * shouldn't be reported any more.
 */
bool amdgpu_vm_handle_fault(struct amdgpu_device *adev, u32 pasid,
			    u32 vmid, u32 node_id, uint64_t addr,
			    uint64_t ts, bool write_fault)
{
	bool is_compute_context = false;
	struct drm_exec exec;
	uint64_t value, flags;
	struct amdgpu_vm *vm;
	int r;

	drm_exec_init(&exec, 0, 1);
	drm_exec_until_all_locked(&exec) {
		vm = amdgpu_vm_lock_by_pasid(adev, pasid, &exec);
		drm_exec_retry_on_contention(&exec);
		if (!vm)
			break;
	}
	if (!vm) {
		drm_exec_fini(&exec);
		return false;
	}

	is_compute_context = vm->is_compute_context;

	if (is_compute_context) {
		__label__ drm_exec_retry;

		/* Release the root PD lock since svm_range_restore_pages
		 * might try to take it.
		 * TODO: rework svm_range_restore_pages so that this isn't
		 * necessary.
		 */
		drm_exec_fini(&exec);

		if (!svm_range_restore_pages(adev, pasid, vmid,
					     node_id, addr >> PAGE_SHIFT, ts, write_fault))
			return true;

		/* Re-acquire the VM lock, could be that the VM was freed in between. */
		drm_exec_init(&exec, 0, 1);
		drm_exec_until_all_locked(&exec) {
			vm = amdgpu_vm_lock_by_pasid(adev, pasid, &exec);
			drm_exec_retry_on_contention(&exec);
			if (!vm)
				break;
		}
		if (!vm) {
			drm_exec_fini(&exec);
			return false;
		}
	}

	addr /= AMDGPU_GPU_PAGE_SIZE;
	flags = AMDGPU_PTE_VALID | AMDGPU_PTE_SNOOPED |
		AMDGPU_PTE_SYSTEM;

	if (is_compute_context) {
		/* Intentionally setting invalid PTE flag
		 * combination to force a no-retry-fault
		 */
		flags = AMDGPU_VM_NORETRY_FLAGS;
		value = 0;
	} else if (amdgpu_vm_fault_stop == AMDGPU_VM_FAULT_STOP_NEVER) {
		/* Redirect the access to the dummy page */
		value = adev->dummy_page_addr;
		flags |= AMDGPU_PTE_EXECUTABLE | AMDGPU_PTE_READABLE |
			AMDGPU_PTE_WRITEABLE;

	} else {
		/* Let the hw retry silently on the PTE */
		value = 0;
	}

	r = dma_resv_reserve_fences(vm->root.bo->tbo.base.resv, 1);
	if (r) {
		pr_debug("failed %d to reserve fence slot\n", r);
		goto error_unlock;
	}

	r = amdgpu_vm_update_range(adev, vm, true, false, false, false,
				   NULL, addr, addr, flags, value, 0, NULL, NULL, NULL);
	if (r)
		goto error_unlock;

	r = amdgpu_vm_update_pdes(adev, vm, true);

error_unlock:
	drm_exec_fini(&exec);
	if (r < 0)
		dev_err(adev->dev, "Can't handle page fault (%d)\n", r);

	return false;
}

#if defined(CONFIG_DEBUG_FS)

/* print the debug info for a specific set of status lists */
static void amdgpu_debugfs_vm_bo_status_info(struct seq_file *m,
					     struct amdgpu_vm_bo_status *lists)
{
	struct amdgpu_vm_bo_base *base;
	unsigned int id;

	id = 0;
	seq_puts(m, "\tEvicted BOs:\n");
	list_for_each_entry(base, &lists->evicted, vm_status) {
		if (!base->bo)
			continue;

		amdgpu_bo_print_info(id++, base->bo, m);
	}

	id = 0;
	seq_puts(m, "\tMoved BOs:\n");
	list_for_each_entry(base, &lists->needs_update, vm_status) {
		if (!base->bo)
			continue;

		amdgpu_bo_print_info(id++, base->bo, m);
	}

	id = 0;
	seq_puts(m, "\tIdle BOs:\n");
	list_for_each_entry(base, &lists->idle, vm_status) {
		if (!base->bo)
			continue;

		amdgpu_bo_print_info(id++, base->bo, m);
	}
}

/**
 * amdgpu_debugfs_vm_bo_info  - print BO info for the VM
 *
 * @vm: Requested VM for printing BO info
 * @m: debugfs file
 *
 * Print BO information in debugfs file for the VM
 */
void amdgpu_debugfs_vm_bo_info(struct amdgpu_vm *vm, struct seq_file *m)
{
	amdgpu_vm_assert_locked(vm);

	seq_puts(m, "\tKernel PT/PDs:\n");
	amdgpu_debugfs_vm_bo_status_info(m, &vm->kernel);

	seq_puts(m, "\tPer VM BOs:\n");
	amdgpu_debugfs_vm_bo_status_info(m, &vm->always_valid);

	seq_puts(m, "\tIndividual BOs:\n");
	spin_lock(&vm->individual_lock);
	amdgpu_debugfs_vm_bo_status_info(m, &vm->individual);
	spin_unlock(&vm->individual_lock);
}
#endif

/**
 * amdgpu_vm_update_fault_cache - update cached fault into.
 * @adev: amdgpu device pointer
 * @pasid: PASID of the VM
 * @addr: Address of the fault
 * @status: GPUVM fault status register
 * @vmhub: which vmhub got the fault
 *
 * Cache the fault info for later use by userspace in debugging.
 */
void amdgpu_vm_update_fault_cache(struct amdgpu_device *adev,
				  unsigned int pasid,
				  uint64_t addr,
				  uint32_t status,
				  unsigned int vmhub)
{
	struct amdgpu_fpriv *fpriv;
	struct amdgpu_vm *vm;
	unsigned long flags;

	amdgpu_pasid_lock(&flags);

	fpriv = amdgpu_pasid_get_fpriv_locked(pasid);
	vm = fpriv ? &fpriv->vm : NULL;
	/* Don't update the fault cache if status is 0.  In the multiple
	 * fault case, subsequent faults will return a 0 status which is
	 * useless for userspace and replaces the useful fault status, so
	 * only update if status is non-0.
	 */
	if (vm && status) {
		vm->fault_info.addr = addr;
		vm->fault_info.status = status;
		/*
		 * Update the fault information globally for later usage
		 * when vm could be stale or freed.
		 */
		adev->vm_manager.fault_info.addr = addr;
		adev->vm_manager.fault_info.vmhub = vmhub;
		adev->vm_manager.fault_info.status = status;

		if (AMDGPU_IS_GFXHUB(vmhub)) {
			vm->fault_info.vmhub = AMDGPU_VMHUB_TYPE_GFX;
			vm->fault_info.vmhub |=
				(vmhub - AMDGPU_GFXHUB_START) << AMDGPU_VMHUB_IDX_SHIFT;
		} else if (AMDGPU_IS_MMHUB0(vmhub)) {
			vm->fault_info.vmhub = AMDGPU_VMHUB_TYPE_MM0;
			vm->fault_info.vmhub |=
				(vmhub - AMDGPU_MMHUB0_START) << AMDGPU_VMHUB_IDX_SHIFT;
		} else if (AMDGPU_IS_MMHUB1(vmhub)) {
			vm->fault_info.vmhub = AMDGPU_VMHUB_TYPE_MM1;
			vm->fault_info.vmhub |=
				(vmhub - AMDGPU_MMHUB1_START) << AMDGPU_VMHUB_IDX_SHIFT;
		} else {
			WARN_ONCE(1, "Invalid vmhub %u\n", vmhub);
		}
	}
	amdgpu_pasid_unlock(flags);
}

void amdgpu_vm_print_task_info(struct amdgpu_device *adev,
			       struct amdgpu_task_info *task_info)
{
	dev_err(adev->dev,
		" Process %s pid %d thread %s pid %d\n",
		task_info->process_name, task_info->tgid,
		task_info->task.comm, task_info->task.pid);
}

void amdgpu_sdma_set_vm_pte_scheds(struct amdgpu_device *adev,
				   const struct amdgpu_vm_pte_funcs *vm_pte_funcs)
{
	struct drm_gpu_scheduler *sched;
	int i;

	for (i = 0; i < adev->sdma.num_instances; i++) {
		if (adev->sdma.has_page_queue)
			sched = &adev->sdma.instance[i].page.sched;
		else
			sched = &adev->sdma.instance[i].ring.sched;
		adev->vm_manager.vm_pte_scheds[i] = sched;
	}
	adev->vm_manager.vm_pte_num_scheds = adev->sdma.num_instances;
	adev->vm_manager.vm_pte_funcs = vm_pte_funcs;
}