/*
 * 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/fence-array.h>
#include <drm/drmP.h>
#include <drm/amdgpu_drm.h>
#include "amdgpu.h"
#include "amdgpu_trace.h"

/*
 * GPUVM
 * 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 are multiple VM page tables active
 * at any given time.  The VM page tables can contain a mix
 * vram pages and system memory pages and system memory pages
 * can be mapped as snooped (cached system pages) or unsnooped
 * (uncached system pages).
 * Each VM has an ID associated with it and there is a page table
 * associated with each VMID.  When execting a command buffer,
 * the kernel tells the the ring 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.
 * Cayman/Trinity support up to 8 active VMs at any given time;
 * SI supports 16.
 */

/* Local structure. Encapsulate some VM table update parameters to reduce
 * the number of function parameters
 */
struct amdgpu_pte_update_params {
        /* amdgpu device we do this update for */
        struct amdgpu_device *adev;
        /* address where to copy page table entries from */
        uint64_t src;
        /* indirect buffer to fill with commands */
        struct amdgpu_ib *ib;
        /* Function which actually does the update */
        void (*func)(struct amdgpu_pte_update_params *params, uint64_t pe,
                     uint64_t addr, unsigned count, uint32_t incr,
                     uint32_t flags);
        /* indicate update pt or its shadow */
        bool shadow;
};

/**
 * amdgpu_vm_num_pde - return the number of page directory entries
 *
 * @adev: amdgpu_device pointer
 *
 * Calculate the number of page directory entries.
 */
static unsigned amdgpu_vm_num_pdes(struct amdgpu_device *adev)
{
        return adev->vm_manager.max_pfn >> amdgpu_vm_block_size;
}

/**
 * amdgpu_vm_directory_size - returns the size of the page directory in bytes
 *
 * @adev: amdgpu_device pointer
 *
 * Calculate the size of the page directory in bytes.
 */
static unsigned amdgpu_vm_directory_size(struct amdgpu_device *adev)
{
        return AMDGPU_GPU_PAGE_ALIGN(amdgpu_vm_num_pdes(adev) * 8);
}

/**
 * amdgpu_vm_get_pd_bo - add the VM PD to a validation list
 *
 * @vm: vm providing the BOs
 * @validated: head of validation list
 * @entry: entry to add
 *
 * Add the page directory to the list of BOs to
 * validate for command submission.
 */
void amdgpu_vm_get_pd_bo(struct amdgpu_vm *vm,
                         struct list_head *validated,
                         struct amdgpu_bo_list_entry *entry)
{
        entry->robj = vm->page_directory;
        entry->priority = 0;
        entry->tv.bo = &vm->page_directory->tbo;
        entry->tv.shared = true;
        entry->user_pages = NULL;
        list_add(&entry->tv.head, validated);
}

/**
 * amdgpu_vm_get_bos - add the vm BOs to a duplicates list
 *
 * @adev: amdgpu device pointer
 * @vm: vm providing the BOs
 * @duplicates: head of duplicates list
 *
 * Add the page directory to the BO duplicates list
 * for command submission.
 */
void amdgpu_vm_get_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
                          struct list_head *duplicates)
{
        uint64_t num_evictions;
        unsigned i;

        /* We only need to validate the page tables
         * if they aren't already valid.
         */
        num_evictions = atomic64_read(&adev->num_evictions);
        if (num_evictions == vm->last_eviction_counter)
                return;

        /* add the vm page table to the list */
        for (i = 0; i <= vm->max_pde_used; ++i) {
                struct amdgpu_bo_list_entry *entry = &vm->page_tables[i].entry;

                if (!entry->robj)
                        continue;

                list_add(&entry->tv.head, duplicates);
        }

}

/**
 * amdgpu_vm_move_pt_bos_in_lru - move the PT BOs to the LRU tail
 *
 * @adev: amdgpu device instance
 * @vm: vm providing the BOs
 *
 * Move the PT BOs to the tail of the LRU.
 */
void amdgpu_vm_move_pt_bos_in_lru(struct amdgpu_device *adev,
                                  struct amdgpu_vm *vm)
{
        struct ttm_bo_global *glob = adev->mman.bdev.glob;
        unsigned i;

        spin_lock(&glob->lru_lock);
        for (i = 0; i <= vm->max_pde_used; ++i) {
                struct amdgpu_bo_list_entry *entry = &vm->page_tables[i].entry;

                if (!entry->robj)
                        continue;

                ttm_bo_move_to_lru_tail(&entry->robj->tbo);
        }
        spin_unlock(&glob->lru_lock);
}

static bool amdgpu_vm_is_gpu_reset(struct amdgpu_device *adev,
                              struct amdgpu_vm_id *id)
{
        return id->current_gpu_reset_count !=
                atomic_read(&adev->gpu_reset_counter) ? true : false;
}

/**
 * amdgpu_vm_grab_id - allocate the next free VMID
 *
 * @vm: vm to allocate id for
 * @ring: ring we want to submit job to
 * @sync: sync object where we add dependencies
 * @fence: fence protecting ID from reuse
 *
 * Allocate an id for the vm, adding fences to the sync obj as necessary.
 */
int amdgpu_vm_grab_id(struct amdgpu_vm *vm, struct amdgpu_ring *ring,
                      struct amdgpu_sync *sync, struct fence *fence,
                      struct amdgpu_job *job)
{
        struct amdgpu_device *adev = ring->adev;
        uint64_t fence_context = adev->fence_context + ring->idx;
        struct fence *updates = sync->last_vm_update;
        struct amdgpu_vm_id *id, *idle;
        struct fence **fences;
        unsigned i;
        int r = 0;

        fences = kmalloc_array(sizeof(void *), adev->vm_manager.num_ids,
                               GFP_KERNEL);
        if (!fences)
                return -ENOMEM;

        mutex_lock(&adev->vm_manager.lock);

        /* Check if we have an idle VMID */
        i = 0;
        list_for_each_entry(idle, &adev->vm_manager.ids_lru, list) {
                fences[i] = amdgpu_sync_peek_fence(&idle->active, ring);
                if (!fences[i])
                        break;
                ++i;
        }

        /* If we can't find a idle VMID to use, wait till one becomes available */
        if (&idle->list == &adev->vm_manager.ids_lru) {
                u64 fence_context = adev->vm_manager.fence_context + ring->idx;
                unsigned seqno = ++adev->vm_manager.seqno[ring->idx];
                struct fence_array *array;
                unsigned j;

                for (j = 0; j < i; ++j)
                        fence_get(fences[j]);

                array = fence_array_create(i, fences, fence_context,
                                           seqno, true);
                if (!array) {
                        for (j = 0; j < i; ++j)
                                fence_put(fences[j]);
                        kfree(fences);
                        r = -ENOMEM;
                        goto error;
                }


                r = amdgpu_sync_fence(ring->adev, sync, &array->base);
                fence_put(&array->base);
                if (r)
                        goto error;

                mutex_unlock(&adev->vm_manager.lock);
                return 0;

        }
        kfree(fences);

        job->vm_needs_flush = true;
        /* Check if we can use a VMID already assigned to this VM */
        i = ring->idx;
        do {
                struct fence *flushed;

                id = vm->ids[i++];
                if (i == AMDGPU_MAX_RINGS)
                        i = 0;

                /* Check all the prerequisites to using this VMID */
                if (!id)
                        continue;
                if (amdgpu_vm_is_gpu_reset(adev, id))
                        continue;

                if (atomic64_read(&id->owner) != vm->client_id)
                        continue;

                if (job->vm_pd_addr != id->pd_gpu_addr)
                        continue;

                if (!id->last_flush)
                        continue;

                if (id->last_flush->context != fence_context &&
                    !fence_is_signaled(id->last_flush))
                        continue;

                flushed  = id->flushed_updates;
                if (updates &&
                    (!flushed || fence_is_later(updates, flushed)))
                        continue;

                /* Good we can use this VMID. Remember this submission as
                 * user of the VMID.
                 */
                r = amdgpu_sync_fence(ring->adev, &id->active, fence);
                if (r)
                        goto error;

                id->current_gpu_reset_count = atomic_read(&adev->gpu_reset_counter);
                list_move_tail(&id->list, &adev->vm_manager.ids_lru);
                vm->ids[ring->idx] = id;

                job->vm_id = id - adev->vm_manager.ids;
                job->vm_needs_flush = false;
                trace_amdgpu_vm_grab_id(vm, ring->idx, job);

                mutex_unlock(&adev->vm_manager.lock);
                return 0;

        } while (i != ring->idx);

        /* Still no ID to use? Then use the idle one found earlier */
        id = idle;

        /* Remember this submission as user of the VMID */
        r = amdgpu_sync_fence(ring->adev, &id->active, fence);
        if (r)
                goto error;

        fence_put(id->first);
        id->first = fence_get(fence);

        fence_put(id->last_flush);
        id->last_flush = NULL;

        fence_put(id->flushed_updates);
        id->flushed_updates = fence_get(updates);

        id->pd_gpu_addr = job->vm_pd_addr;
        id->current_gpu_reset_count = atomic_read(&adev->gpu_reset_counter);
        list_move_tail(&id->list, &adev->vm_manager.ids_lru);
        atomic64_set(&id->owner, vm->client_id);
        vm->ids[ring->idx] = id;

        job->vm_id = id - adev->vm_manager.ids;
        trace_amdgpu_vm_grab_id(vm, ring->idx, job);

error:
        mutex_unlock(&adev->vm_manager.lock);
        return r;
}

static bool amdgpu_vm_ring_has_compute_vm_bug(struct amdgpu_ring *ring)
{
        struct amdgpu_device *adev = ring->adev;
        const struct amdgpu_ip_block_version *ip_block;

        if (ring->type != AMDGPU_RING_TYPE_COMPUTE)
                /* only compute rings */
                return false;

        ip_block = amdgpu_get_ip_block(adev, AMD_IP_BLOCK_TYPE_GFX);
        if (!ip_block)
                return false;

        if (ip_block->major <= 7) {
                /* gfx7 has no workaround */
                return true;
        } else if (ip_block->major == 8) {
                if (adev->gfx.mec_fw_version >= 673)
                        /* gfx8 is fixed in MEC firmware 673 */
                        return false;
                else
                        return true;
        }
        return false;
}

/**
 * amdgpu_vm_flush - hardware flush the vm
 *
 * @ring: ring to use for flush
 * @vm_id: vmid number to use
 * @pd_addr: address of the page directory
 *
 * Emit a VM flush when it is necessary.
 */
int amdgpu_vm_flush(struct amdgpu_ring *ring, struct amdgpu_job *job)
{
        struct amdgpu_device *adev = ring->adev;
        struct amdgpu_vm_id *id = &adev->vm_manager.ids[job->vm_id];
        bool gds_switch_needed = ring->funcs->emit_gds_switch && (
                id->gds_base != job->gds_base ||
                id->gds_size != job->gds_size ||
                id->gws_base != job->gws_base ||
                id->gws_size != job->gws_size ||
                id->oa_base != job->oa_base ||
                id->oa_size != job->oa_size);
        int r;

        if (ring->funcs->emit_pipeline_sync && (
            job->vm_needs_flush || gds_switch_needed ||
            amdgpu_vm_ring_has_compute_vm_bug(ring)))
                amdgpu_ring_emit_pipeline_sync(ring);

        if (ring->funcs->emit_vm_flush && (job->vm_needs_flush ||
            amdgpu_vm_is_gpu_reset(adev, id))) {
                struct fence *fence;

                trace_amdgpu_vm_flush(job->vm_pd_addr, ring->idx, job->vm_id);
                amdgpu_ring_emit_vm_flush(ring, job->vm_id, job->vm_pd_addr);

                r = amdgpu_fence_emit(ring, &fence);
                if (r)
                        return r;

                mutex_lock(&adev->vm_manager.lock);
                fence_put(id->last_flush);
                id->last_flush = fence;
                mutex_unlock(&adev->vm_manager.lock);
        }

        if (gds_switch_needed) {
                id->gds_base = job->gds_base;
                id->gds_size = job->gds_size;
                id->gws_base = job->gws_base;
                id->gws_size = job->gws_size;
                id->oa_base = job->oa_base;
                id->oa_size = job->oa_size;
                amdgpu_ring_emit_gds_switch(ring, job->vm_id,
                                            job->gds_base, job->gds_size,
                                            job->gws_base, job->gws_size,
                                            job->oa_base, job->oa_size);
        }

        return 0;
}

/**
 * amdgpu_vm_reset_id - reset VMID to zero
 *
 * @adev: amdgpu device structure
 * @vm_id: vmid number to use
 *
 * Reset saved GDW, GWS and OA to force switch on next flush.
 */
void amdgpu_vm_reset_id(struct amdgpu_device *adev, unsigned vm_id)
{
        struct amdgpu_vm_id *id = &adev->vm_manager.ids[vm_id];

        id->gds_base = 0;
        id->gds_size = 0;
        id->gws_base = 0;
        id->gws_size = 0;
        id->oa_base = 0;
        id->oa_size = 0;
}

/**
 * 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!
 */
struct amdgpu_bo_va *amdgpu_vm_bo_find(struct amdgpu_vm *vm,
                                       struct amdgpu_bo *bo)
{
        struct amdgpu_bo_va *bo_va;

        list_for_each_entry(bo_va, &bo->va, bo_list) {
                if (bo_va->vm == vm) {
                        return bo_va;
                }
        }
        return NULL;
}

/**
 * amdgpu_vm_do_set_ptes - helper to call the right asic function
 *
 * @params: see amdgpu_pte_update_params definition
 * @pe: addr of the page entry
 * @addr: dst addr to write into pe
 * @count: number of page entries to update
 * @incr: increase next addr by incr bytes
 * @flags: hw access flags
 *
 * Traces the parameters and calls the right asic functions
 * to setup the page table using the DMA.
 */
static void amdgpu_vm_do_set_ptes(struct amdgpu_pte_update_params *params,
                                  uint64_t pe, uint64_t addr,
                                  unsigned count, uint32_t incr,
                                  uint32_t flags)
{
        trace_amdgpu_vm_set_ptes(pe, addr, count, incr, flags);

        if (count < 3) {
                amdgpu_vm_write_pte(params->adev, params->ib, pe,
                                    addr | flags, count, incr);

        } else {
                amdgpu_vm_set_pte_pde(params->adev, params->ib, pe, addr,
                                      count, incr, flags);
        }
}

/**
 * amdgpu_vm_do_copy_ptes - copy the PTEs from the GART
 *
 * @params: see amdgpu_pte_update_params definition
 * @pe: addr of the page entry
 * @addr: dst addr to write into pe
 * @count: number of page entries to update
 * @incr: increase next addr by incr bytes
 * @flags: hw access flags
 *
 * Traces the parameters and calls the DMA function to copy the PTEs.
 */
static void amdgpu_vm_do_copy_ptes(struct amdgpu_pte_update_params *params,
                                   uint64_t pe, uint64_t addr,
                                   unsigned count, uint32_t incr,
                                   uint32_t flags)
{
        uint64_t src = (params->src + (addr >> 12) * 8);


        trace_amdgpu_vm_copy_ptes(pe, src, count);

        amdgpu_vm_copy_pte(params->adev, params->ib, pe, src, count);
}

/**
 * amdgpu_vm_clear_bo - initially clear the page dir/table
 *
 * @adev: amdgpu_device pointer
 * @bo: bo to clear
 *
 * need to reserve bo first before calling it.
 */
static int amdgpu_vm_clear_bo(struct amdgpu_device *adev,
                              struct amdgpu_vm *vm,
                              struct amdgpu_bo *bo)
{
        struct amdgpu_ring *ring;
        struct fence *fence = NULL;
        struct amdgpu_job *job;
        struct amdgpu_pte_update_params params;
        unsigned entries;
        uint64_t addr;
        int r;

        ring = container_of(vm->entity.sched, struct amdgpu_ring, sched);

        r = reservation_object_reserve_shared(bo->tbo.resv);
        if (r)
                return r;

        r = ttm_bo_validate(&bo->tbo, &bo->placement, true, false);
        if (r)
                goto error;

        r = amdgpu_ttm_bind(&bo->tbo, &bo->tbo.mem);
        if (r)
                goto error;

        addr = amdgpu_bo_gpu_offset(bo);
        entries = amdgpu_bo_size(bo) / 8;

        r = amdgpu_job_alloc_with_ib(adev, 64, &job);
        if (r)
                goto error;

        memset(&params, 0, sizeof(params));
        params.adev = adev;
        params.ib = &job->ibs[0];
        amdgpu_vm_do_set_ptes(&params, addr, 0, entries, 0, 0);
        amdgpu_ring_pad_ib(ring, &job->ibs[0]);

        WARN_ON(job->ibs[0].length_dw > 64);
        r = amdgpu_job_submit(job, ring, &vm->entity,
                              AMDGPU_FENCE_OWNER_VM, &fence);
        if (r)
                goto error_free;

        amdgpu_bo_fence(bo, fence, true);
        fence_put(fence);
        return 0;

error_free:
        amdgpu_job_free(job);

error:
        return r;
}

/**
 * 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 and return the pointer for the page table entry.
 */
static 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;
}

static int amdgpu_vm_update_pd_or_shadow(struct amdgpu_device *adev,
                                         struct amdgpu_vm *vm,
                                         bool shadow)
{
        struct amdgpu_ring *ring;
        struct amdgpu_bo *pd = shadow ? vm->page_directory->shadow :
                vm->page_directory;
        uint64_t pd_addr;
        uint32_t incr = AMDGPU_VM_PTE_COUNT * 8;
        uint64_t last_pde = ~0, last_pt = ~0;
        unsigned count = 0, pt_idx, ndw;
        struct amdgpu_job *job;
        struct amdgpu_pte_update_params params;
        struct fence *fence = NULL;

        int r;

        if (!pd)
                return 0;

        r = amdgpu_ttm_bind(&pd->tbo, &pd->tbo.mem);
        if (r)
                return r;

        pd_addr = amdgpu_bo_gpu_offset(pd);
        ring = container_of(vm->entity.sched, struct amdgpu_ring, sched);

        /* padding, etc. */
        ndw = 64;

        /* assume the worst case */
        ndw += vm->max_pde_used * 6;

        r = amdgpu_job_alloc_with_ib(adev, ndw * 4, &job);
        if (r)
                return r;

        memset(&params, 0, sizeof(params));
        params.adev = adev;
        params.ib = &job->ibs[0];

        /* walk over the address space and update the page directory */
        for (pt_idx = 0; pt_idx <= vm->max_pde_used; ++pt_idx) {
                struct amdgpu_bo *bo = vm->page_tables[pt_idx].entry.robj;
                uint64_t pde, pt;

                if (bo == NULL)
                        continue;

                if (bo->shadow) {
                        struct amdgpu_bo *shadow = bo->shadow;

                        r = amdgpu_ttm_bind(&shadow->tbo, &shadow->tbo.mem);
                        if (r)
                                return r;
                }

                pt = amdgpu_bo_gpu_offset(bo);
                if (!shadow) {
                        if (vm->page_tables[pt_idx].addr == pt)
                                continue;
                        vm->page_tables[pt_idx].addr = pt;
                } else {
                        if (vm->page_tables[pt_idx].shadow_addr == pt)
                                continue;
                        vm->page_tables[pt_idx].shadow_addr = pt;
                }

                pde = pd_addr + pt_idx * 8;
                if (((last_pde + 8 * count) != pde) ||
                    ((last_pt + incr * count) != pt) ||
                    (count == AMDGPU_VM_MAX_UPDATE_SIZE)) {

                        if (count) {
                                amdgpu_vm_do_set_ptes(&params, last_pde,
                                                      last_pt, count, incr,
                                                      AMDGPU_PTE_VALID);
                        }

                        count = 1;
                        last_pde = pde;
                        last_pt = pt;
                } else {
                        ++count;
                }
        }

        if (count)
                amdgpu_vm_do_set_ptes(&params, last_pde, last_pt,
                                      count, incr, AMDGPU_PTE_VALID);

        if (params.ib->length_dw != 0) {
                amdgpu_ring_pad_ib(ring, params.ib);
                amdgpu_sync_resv(adev, &job->sync, pd->tbo.resv,
                                 AMDGPU_FENCE_OWNER_VM);
                WARN_ON(params.ib->length_dw > ndw);
                r = amdgpu_job_submit(job, ring, &vm->entity,
                                      AMDGPU_FENCE_OWNER_VM, &fence);
                if (r)
                        goto error_free;

                amdgpu_bo_fence(pd, fence, true);
                fence_put(vm->page_directory_fence);
                vm->page_directory_fence = fence_get(fence);
                fence_put(fence);

        } else {
                amdgpu_job_free(job);
        }

        return 0;

error_free:
        amdgpu_job_free(job);
        return r;
}

/*
 * amdgpu_vm_update_pdes - make sure that page directory is valid
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @start: start of GPU address range
 * @end: end of GPU address range
 *
 * Allocates new page tables if necessary
 * and updates the page directory.
 * Returns 0 for success, error for failure.
 */
int amdgpu_vm_update_page_directory(struct amdgpu_device *adev,
                                   struct amdgpu_vm *vm)
{
        int r;

        r = amdgpu_vm_update_pd_or_shadow(adev, vm, true);
        if (r)
                return r;
        return amdgpu_vm_update_pd_or_shadow(adev, vm, false);
}

/**
 * amdgpu_vm_update_ptes - make sure that page tables are valid
 *
 * @params: see amdgpu_pte_update_params definition
 * @vm: requested vm
 * @start: start of GPU address range
 * @end: end of GPU address range
 * @dst: destination address to map to, the next dst inside the function
 * @flags: mapping flags
 *
 * Update the page tables in the range @start - @end.
 */
static void amdgpu_vm_update_ptes(struct amdgpu_pte_update_params *params,
                                  struct amdgpu_vm *vm,
                                  uint64_t start, uint64_t end,
                                  uint64_t dst, uint32_t flags)
{
        const uint64_t mask = AMDGPU_VM_PTE_COUNT - 1;

        uint64_t cur_pe_start, cur_nptes, cur_dst;
        uint64_t addr; /* next GPU address to be updated */
        uint64_t pt_idx;
        struct amdgpu_bo *pt;
        unsigned nptes; /* next number of ptes to be updated */
        uint64_t next_pe_start;

        /* initialize the variables */
        addr = start;
        pt_idx = addr >> amdgpu_vm_block_size;
        pt = vm->page_tables[pt_idx].entry.robj;
        if (params->shadow) {
                if (!pt->shadow)
                        return;
                pt = vm->page_tables[pt_idx].entry.robj->shadow;
        }
        if ((addr & ~mask) == (end & ~mask))
                nptes = end - addr;
        else
                nptes = AMDGPU_VM_PTE_COUNT - (addr & mask);

        cur_pe_start = amdgpu_bo_gpu_offset(pt);
        cur_pe_start += (addr & mask) * 8;
        cur_nptes = nptes;
        cur_dst = dst;

        /* for next ptb*/
        addr += nptes;
        dst += nptes * AMDGPU_GPU_PAGE_SIZE;

        /* walk over the address space and update the page tables */
        while (addr < end) {
                pt_idx = addr >> amdgpu_vm_block_size;
                pt = vm->page_tables[pt_idx].entry.robj;
                if (params->shadow) {
                        if (!pt->shadow)
                                return;
                        pt = vm->page_tables[pt_idx].entry.robj->shadow;
                }

                if ((addr & ~mask) == (end & ~mask))
                        nptes = end - addr;
                else
                        nptes = AMDGPU_VM_PTE_COUNT - (addr & mask);

                next_pe_start = amdgpu_bo_gpu_offset(pt);
                next_pe_start += (addr & mask) * 8;

                if ((cur_pe_start + 8 * cur_nptes) == next_pe_start &&
                    ((cur_nptes + nptes) <= AMDGPU_VM_MAX_UPDATE_SIZE)) {
                        /* The next ptb is consecutive to current ptb.
                         * Don't call the update function now.
                         * Will update two ptbs together in future.
                        */
                        cur_nptes += nptes;
                } else {
                        params->func(params, cur_pe_start, cur_dst, cur_nptes,
                                     AMDGPU_GPU_PAGE_SIZE, flags);

                        cur_pe_start = next_pe_start;
                        cur_nptes = nptes;
                        cur_dst = dst;
                }

                /* for next ptb*/
                addr += nptes;
                dst += nptes * AMDGPU_GPU_PAGE_SIZE;
        }

        params->func(params, cur_pe_start, cur_dst, cur_nptes,
                     AMDGPU_GPU_PAGE_SIZE, flags);
}

/*
 * amdgpu_vm_frag_ptes - add fragment information to PTEs
 *
 * @params: see amdgpu_pte_update_params definition
 * @vm: requested vm
 * @start: first PTE to handle
 * @end: last PTE to handle
 * @dst: addr those PTEs should point to
 * @flags: hw mapping flags
 */
static void amdgpu_vm_frag_ptes(struct amdgpu_pte_update_params *params,
                                struct amdgpu_vm *vm,
                                uint64_t start, uint64_t end,
                                uint64_t dst, uint32_t flags)
{
        /**
         * The MC L1 TLB supports variable sized pages, based on a fragment
         * field in the PTE. When this field is set to a non-zero value, page
         * granularity is increased from 4KB to (1 << (12 + frag)). The PTE
         * flags are considered valid for all PTEs within the fragment range
         * and corresponding mappings are assumed to be physically contiguous.
         *
         * The L1 TLB can store a single PTE for the whole fragment,
         * significantly increasing the space available for translation
         * caching. This leads to large improvements in throughput when the
         * TLB is under pressure.
         *
         * The L2 TLB distributes small and large fragments into two
         * asymmetric partitions. The large fragment cache is significantly
         * larger. Thus, we try to use large fragments wherever possible.
         * Userspace can support this by aligning virtual base address and
         * allocation size to the fragment size.
         */

        /* SI and newer are optimized for 64KB */
        uint64_t frag_flags = AMDGPU_PTE_FRAG(AMDGPU_LOG2_PAGES_PER_FRAG);
        uint64_t frag_align = 1 << AMDGPU_LOG2_PAGES_PER_FRAG;

        uint64_t frag_start = ALIGN(start, frag_align);
        uint64_t frag_end = end & ~(frag_align - 1);

        /* system pages are non continuously */
        if (params->src || !(flags & AMDGPU_PTE_VALID) ||
            (frag_start >= frag_end)) {

                amdgpu_vm_update_ptes(params, vm, start, end, dst, flags);
                return;
        }

        /* handle the 4K area at the beginning */
        if (start != frag_start) {
                amdgpu_vm_update_ptes(params, vm, start, frag_start,
                                      dst, flags);
                dst += (frag_start - start) * AMDGPU_GPU_PAGE_SIZE;
        }

        /* handle the area in the middle */
        amdgpu_vm_update_ptes(params, vm, frag_start, frag_end, dst,
                              flags | frag_flags);

        /* handle the 4K area at the end */
        if (frag_end != end) {
                dst += (frag_end - frag_start) * AMDGPU_GPU_PAGE_SIZE;
                amdgpu_vm_update_ptes(params, vm, frag_end, end, dst, flags);
        }
}

/**
 * amdgpu_vm_bo_update_mapping - update a mapping in the vm page table
 *
 * @adev: amdgpu_device pointer
 * @exclusive: fence we need to sync to
 * @src: address where to copy page table entries from
 * @pages_addr: DMA addresses to use for mapping
 * @vm: requested vm
 * @start: start of mapped range
 * @last: last mapped entry
 * @flags: flags for the entries
 * @addr: addr to set the area to
 * @fence: optional resulting fence
 *
 * Fill in the page table entries between @start and @last.
 * Returns 0 for success, -EINVAL for failure.
 */
static int amdgpu_vm_bo_update_mapping(struct amdgpu_device *adev,
                                       struct fence *exclusive,
                                       uint64_t src,
                                       dma_addr_t *pages_addr,
                                       struct amdgpu_vm *vm,
                                       uint64_t start, uint64_t last,
                                       uint32_t flags, uint64_t addr,
                                       struct fence **fence)
{
        struct amdgpu_ring *ring;
        void *owner = AMDGPU_FENCE_OWNER_VM;
        unsigned nptes, ncmds, ndw;
        struct amdgpu_job *job;
        struct amdgpu_pte_update_params params;
        struct fence *f = NULL;
        int r;

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

        ring = container_of(vm->entity.sched, struct amdgpu_ring, sched);

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

        /* sync to everything on unmapping */
        if (!(flags & AMDGPU_PTE_VALID))
                owner = AMDGPU_FENCE_OWNER_UNDEFINED;

        nptes = last - start + 1;

        /*
         * reserve space for one command every (1 << BLOCK_SIZE)
         *  entries or 2k dwords (whatever is smaller)
         */
        ncmds = (nptes >> min(amdgpu_vm_block_size, 11)) + 1;

        /* padding, etc. */
        ndw = 64;

        if (src) {
                /* only copy commands needed */
                ndw += ncmds * 7;

                params.func = amdgpu_vm_do_copy_ptes;

        } else if (pages_addr) {
                /* copy commands needed */
                ndw += ncmds * 7;

                /* and also PTEs */
                ndw += nptes * 2;

                params.func = amdgpu_vm_do_copy_ptes;

        } else {
                /* set page commands needed */
                ndw += ncmds * 10;

                /* two extra commands for begin/end of fragment */
                ndw += 2 * 10;

                params.func = amdgpu_vm_do_set_ptes;
        }

        r = amdgpu_job_alloc_with_ib(adev, ndw * 4, &job);
        if (r)
                return r;

        params.ib = &job->ibs[0];

        if (!src && pages_addr) {
                uint64_t *pte;
                unsigned i;

                /* Put the PTEs at the end of the IB. */
                i = ndw - nptes * 2;
                pte= (uint64_t *)&(job->ibs->ptr[i]);
                params.src = job->ibs->gpu_addr + i * 4;

                for (i = 0; i < nptes; ++i) {
                        pte[i] = amdgpu_vm_map_gart(pages_addr, addr + i *
                                                    AMDGPU_GPU_PAGE_SIZE);
                        pte[i] |= flags;
                }
                addr = 0;
        }

        r = amdgpu_sync_fence(adev, &job->sync, exclusive);
        if (r)
                goto error_free;

        r = amdgpu_sync_resv(adev, &job->sync, vm->page_directory->tbo.resv,
                             owner);
        if (r)
                goto error_free;

        r = reservation_object_reserve_shared(vm->page_directory->tbo.resv);
        if (r)
                goto error_free;

        params.shadow = true;
        amdgpu_vm_frag_ptes(&params, vm, start, last + 1, addr, flags);
        params.shadow = false;
        amdgpu_vm_frag_ptes(&params, vm, start, last + 1, addr, flags);

        amdgpu_ring_pad_ib(ring, params.ib);
        WARN_ON(params.ib->length_dw > ndw);
        r = amdgpu_job_submit(job, ring, &vm->entity,
                              AMDGPU_FENCE_OWNER_VM, &f);
        if (r)
                goto error_free;

        amdgpu_bo_fence(vm->page_directory, f, true);
        if (fence) {
                fence_put(*fence);
                *fence = fence_get(f);
        }
        fence_put(f);
        return 0;

error_free:
        amdgpu_job_free(job);
        return r;
}

/**
 * amdgpu_vm_bo_split_mapping - split a mapping into smaller chunks
 *
 * @adev: amdgpu_device pointer
 * @exclusive: fence we need to sync to
 * @gtt_flags: flags as they are used for GTT
 * @pages_addr: DMA addresses to use for mapping
 * @vm: requested vm
 * @mapping: mapped range and flags to use for the update
 * @addr: addr to set the area to
 * @flags: HW flags for the mapping
 * @fence: optional resulting fence
 *
 * Split the mapping into smaller chunks so that each update fits
 * into a SDMA IB.
 * Returns 0 for success, -EINVAL for failure.
 */
static int amdgpu_vm_bo_split_mapping(struct amdgpu_device *adev,
                                      struct fence *exclusive,
                                      uint32_t gtt_flags,
                                      dma_addr_t *pages_addr,
                                      struct amdgpu_vm *vm,
                                      struct amdgpu_bo_va_mapping *mapping,
                                      uint32_t flags, uint64_t addr,
                                      struct fence **fence)
{
        const uint64_t max_size = 64ULL * 1024ULL * 1024ULL / AMDGPU_GPU_PAGE_SIZE;

        uint64_t src = 0, start = mapping->it.start;
        int r;

        /* 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_PTE_READABLE))
                flags &= ~AMDGPU_PTE_READABLE;
        if (!(mapping->flags & AMDGPU_PTE_WRITEABLE))
                flags &= ~AMDGPU_PTE_WRITEABLE;

        trace_amdgpu_vm_bo_update(mapping);

        if (pages_addr) {
                if (flags == gtt_flags)
                        src = adev->gart.table_addr + (addr >> 12) * 8;
                addr = 0;
        }
        addr += mapping->offset;

        if (!pages_addr || src)
                return amdgpu_vm_bo_update_mapping(adev, exclusive,
                                                   src, pages_addr, vm,
                                                   start, mapping->it.last,
                                                   flags, addr, fence);

        while (start != mapping->it.last + 1) {
                uint64_t last;

                last = min((uint64_t)mapping->it.last, start + max_size - 1);
                r = amdgpu_vm_bo_update_mapping(adev, exclusive,
                                                src, pages_addr, vm,
                                                start, last, flags, addr,
                                                fence);
                if (r)
                        return r;

                start = last + 1;
                addr += max_size * AMDGPU_GPU_PAGE_SIZE;
        }

        return 0;
}

/**
 * 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_vm *vm = bo_va->vm;
        struct amdgpu_bo_va_mapping *mapping;
        dma_addr_t *pages_addr = NULL;
        uint32_t gtt_flags, flags;
        struct ttm_mem_reg *mem;
        struct fence *exclusive;
        uint64_t addr;
        int r;

        if (clear) {
                mem = NULL;
                addr = 0;
                exclusive = NULL;
        } else {
                struct ttm_dma_tt *ttm;

                mem = &bo_va->bo->tbo.mem;
                addr = (u64)mem->start << PAGE_SHIFT;
                switch (mem->mem_type) {
                case TTM_PL_TT:
                        ttm = container_of(bo_va->bo->tbo.ttm, struct
                                           ttm_dma_tt, ttm);
                        pages_addr = ttm->dma_address;
                        break;

                case TTM_PL_VRAM:
                        addr += adev->vm_manager.vram_base_offset;
                        break;

                default:
                        break;
                }

                exclusive = reservation_object_get_excl(bo_va->bo->tbo.resv);
        }

        flags = amdgpu_ttm_tt_pte_flags(adev, bo_va->bo->tbo.ttm, mem);
        gtt_flags = (amdgpu_ttm_is_bound(bo_va->bo->tbo.ttm) &&
                adev == bo_va->bo->adev) ? flags : 0;

        spin_lock(&vm->status_lock);
        if (!list_empty(&bo_va->vm_status))
                list_splice_init(&bo_va->valids, &bo_va->invalids);
        spin_unlock(&vm->status_lock);

        list_for_each_entry(mapping, &bo_va->invalids, list) {
                r = amdgpu_vm_bo_split_mapping(adev, exclusive,
                                               gtt_flags, pages_addr, vm,
                                               mapping, flags, addr,
                                               &bo_va->last_pt_update);
                if (r)
                        return r;
        }

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

                list_for_each_entry(mapping, &bo_va->invalids, list)
                        trace_amdgpu_vm_bo_mapping(mapping);
        }

        spin_lock(&vm->status_lock);
        list_splice_init(&bo_va->invalids, &bo_va->valids);
        list_del_init(&bo_va->vm_status);
        if (clear)
                list_add(&bo_va->vm_status, &vm->cleared);
        spin_unlock(&vm->status_lock);

        return 0;
}

/**
 * amdgpu_vm_clear_freed - clear freed BOs in the PT
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 *
 * Make sure all freed BOs are cleared in the PT.
 * Returns 0 for success.
 *
 * PTs have to be reserved and mutex must be locked!
 */
int amdgpu_vm_clear_freed(struct amdgpu_device *adev,
                          struct amdgpu_vm *vm)
{
        struct amdgpu_bo_va_mapping *mapping;
        int r;

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

                r = amdgpu_vm_bo_split_mapping(adev, NULL, 0, NULL, vm, mapping,
                                               0, 0, NULL);
                kfree(mapping);
                if (r)
                        return r;

        }
        return 0;

}

/**
 * amdgpu_vm_clear_invalids - clear invalidated BOs in the PT
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 *
 * Make sure all invalidated BOs are cleared in the PT.
 * Returns 0 for success.
 *
 * PTs have to be reserved and mutex must be locked!
 */
int amdgpu_vm_clear_invalids(struct amdgpu_device *adev,
                             struct amdgpu_vm *vm, struct amdgpu_sync *sync)
{
        struct amdgpu_bo_va *bo_va = NULL;
        int r = 0;

        spin_lock(&vm->status_lock);
        while (!list_empty(&vm->invalidated)) {
                bo_va = list_first_entry(&vm->invalidated,
                        struct amdgpu_bo_va, vm_status);
                spin_unlock(&vm->status_lock);

                r = amdgpu_vm_bo_update(adev, bo_va, true);
                if (r)
                        return r;

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

        if (bo_va)
                r = amdgpu_sync_fence(adev, sync, bo_va->last_pt_update);

        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;

        bo_va = kzalloc(sizeof(struct amdgpu_bo_va), GFP_KERNEL);
        if (bo_va == NULL) {
                return NULL;
        }
        bo_va->vm = vm;
        bo_va->bo = bo;
        bo_va->ref_count = 1;
        INIT_LIST_HEAD(&bo_va->bo_list);
        INIT_LIST_HEAD(&bo_va->valids);
        INIT_LIST_HEAD(&bo_va->invalids);
        INIT_LIST_HEAD(&bo_va->vm_status);

        list_add_tail(&bo_va->bo_list, &bo->va);

        return bo_va;
}

/**
 * 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
 * @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;
        struct amdgpu_vm *vm = bo_va->vm;
        struct interval_tree_node *it;
        unsigned last_pfn, pt_idx;
        uint64_t eaddr;
        int r;

        /* validate the parameters */
        if (saddr & AMDGPU_GPU_PAGE_MASK || offset & AMDGPU_GPU_PAGE_MASK ||
            size == 0 || size & AMDGPU_GPU_PAGE_MASK)
                return -EINVAL;

        /* make sure object fit at this offset */
        eaddr = saddr + size - 1;
        if ((saddr >= eaddr) || (offset + size > amdgpu_bo_size(bo_va->bo)))
                return -EINVAL;

        last_pfn = eaddr / AMDGPU_GPU_PAGE_SIZE;
        if (last_pfn >= adev->vm_manager.max_pfn) {
                dev_err(adev->dev, "va above limit (0x%08X >= 0x%08X)\n",
                        last_pfn, adev->vm_manager.max_pfn);
                return -EINVAL;
        }

        saddr /= AMDGPU_GPU_PAGE_SIZE;
        eaddr /= AMDGPU_GPU_PAGE_SIZE;

        it = interval_tree_iter_first(&vm->va, saddr, eaddr);
        if (it) {
                struct amdgpu_bo_va_mapping *tmp;
                tmp = container_of(it, struct amdgpu_bo_va_mapping, it);
                /* 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_va->bo, saddr, eaddr,
                        tmp->it.start, tmp->it.last + 1);
                r = -EINVAL;
                goto error;
        }

        mapping = kmalloc(sizeof(*mapping), GFP_KERNEL);
        if (!mapping) {
                r = -ENOMEM;
                goto error;
        }

        INIT_LIST_HEAD(&mapping->list);
        mapping->it.start = saddr;
        mapping->it.last = eaddr;
        mapping->offset = offset;
        mapping->flags = flags;

        list_add(&mapping->list, &bo_va->invalids);
        interval_tree_insert(&mapping->it, &vm->va);

        /* Make sure the page tables are allocated */
        saddr >>= amdgpu_vm_block_size;
        eaddr >>= amdgpu_vm_block_size;

        BUG_ON(eaddr >= amdgpu_vm_num_pdes(adev));

        if (eaddr > vm->max_pde_used)
                vm->max_pde_used = eaddr;

        /* walk over the address space and allocate the page tables */
        for (pt_idx = saddr; pt_idx <= eaddr; ++pt_idx) {
                struct reservation_object *resv = vm->page_directory->tbo.resv;
                struct amdgpu_bo_list_entry *entry;
                struct amdgpu_bo *pt;

                entry = &vm->page_tables[pt_idx].entry;
                if (entry->robj)
                        continue;

                r = amdgpu_bo_create(adev, AMDGPU_VM_PTE_COUNT * 8,
                                     AMDGPU_GPU_PAGE_SIZE, true,
                                     AMDGPU_GEM_DOMAIN_VRAM,
                                     AMDGPU_GEM_CREATE_NO_CPU_ACCESS |
                                     AMDGPU_GEM_CREATE_SHADOW,
                                     NULL, resv, &pt);
                if (r)
                        goto error_free;

                /* Keep a reference to the page table to avoid freeing
                 * them up in the wrong order.
                 */
                pt->parent = amdgpu_bo_ref(vm->page_directory);

                r = amdgpu_vm_clear_bo(adev, vm, pt);
                if (r) {
                        amdgpu_bo_unref(&pt->shadow);
                        amdgpu_bo_unref(&pt);
                        goto error_free;
                }

                if (pt->shadow) {
                        r = amdgpu_vm_clear_bo(adev, vm, pt->shadow);
                        if (r) {
                                amdgpu_bo_unref(&pt->shadow);
                                amdgpu_bo_unref(&pt);
                                goto error_free;
                        }
                }

                entry->robj = pt;
                entry->priority = 0;
                entry->tv.bo = &entry->robj->tbo;
                entry->tv.shared = true;
                entry->user_pages = NULL;
                vm->page_tables[pt_idx].addr = 0;
        }

        return 0;

error_free:
        list_del(&mapping->list);
        interval_tree_remove(&mapping->it, &vm->va);
        trace_amdgpu_vm_bo_unmap(bo_va, mapping);
        kfree(mapping);

error:
        return r;
}

/**
 * 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->vm;
        bool valid = true;

        saddr /= AMDGPU_GPU_PAGE_SIZE;

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

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

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

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

        list_del(&mapping->list);
        interval_tree_remove(&mapping->it, &vm->va);
        trace_amdgpu_vm_bo_unmap(bo_va, mapping);

        if (valid)
                list_add(&mapping->list, &vm->freed);
        else
                kfree(mapping);

        return 0;
}

/**
 * amdgpu_vm_bo_rmv - remove a bo to 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_rmv(struct amdgpu_device *adev,
                      struct amdgpu_bo_va *bo_va)
{
        struct amdgpu_bo_va_mapping *mapping, *next;
        struct amdgpu_vm *vm = bo_va->vm;

        list_del(&bo_va->bo_list);

        spin_lock(&vm->status_lock);
        list_del(&bo_va->vm_status);
        spin_unlock(&vm->status_lock);

        list_for_each_entry_safe(mapping, next, &bo_va->valids, list) {
                list_del(&mapping->list);
                interval_tree_remove(&mapping->it, &vm->va);
                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);
                interval_tree_remove(&mapping->it, &vm->va);
                kfree(mapping);
        }

        fence_put(bo_va->last_pt_update);
        kfree(bo_va);
}

/**
 * amdgpu_vm_bo_invalidate - mark the bo as invalid
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 * @bo: amdgpu buffer object
 *
 * Mark @bo as invalid.
 */
void amdgpu_vm_bo_invalidate(struct amdgpu_device *adev,
                             struct amdgpu_bo *bo)
{
        struct amdgpu_bo_va *bo_va;

        list_for_each_entry(bo_va, &bo->va, bo_list) {
                spin_lock(&bo_va->vm->status_lock);
                if (list_empty(&bo_va->vm_status))
                        list_add(&bo_va->vm_status, &bo_va->vm->invalidated);
                spin_unlock(&bo_va->vm->status_lock);
        }
}

/**
 * amdgpu_vm_init - initialize a vm instance
 *
 * @adev: amdgpu_device pointer
 * @vm: requested vm
 *
 * Init @vm fields.
 */
int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm)
{
        const unsigned align = min(AMDGPU_VM_PTB_ALIGN_SIZE,
                AMDGPU_VM_PTE_COUNT * 8);
        unsigned pd_size, pd_entries;
        unsigned ring_instance;
        struct amdgpu_ring *ring;
        struct amd_sched_rq *rq;
        int i, r;

        for (i = 0; i < AMDGPU_MAX_RINGS; ++i)
                vm->ids[i] = NULL;
        vm->va = RB_ROOT;
        vm->client_id = atomic64_inc_return(&adev->vm_manager.client_counter);
        spin_lock_init(&vm->status_lock);
        INIT_LIST_HEAD(&vm->invalidated);
        INIT_LIST_HEAD(&vm->cleared);
        INIT_LIST_HEAD(&vm->freed);

        pd_size = amdgpu_vm_directory_size(adev);
        pd_entries = amdgpu_vm_num_pdes(adev);

        /* allocate page table array */
        vm->page_tables = drm_calloc_large(pd_entries, sizeof(struct amdgpu_vm_pt));
        if (vm->page_tables == NULL) {
                DRM_ERROR("Cannot allocate memory for page table array\n");
                return -ENOMEM;
        }

        /* create scheduler entity for page table updates */

        ring_instance = atomic_inc_return(&adev->vm_manager.vm_pte_next_ring);
        ring_instance %= adev->vm_manager.vm_pte_num_rings;
        ring = adev->vm_manager.vm_pte_rings[ring_instance];
        rq = &ring->sched.sched_rq[AMD_SCHED_PRIORITY_KERNEL];
        r = amd_sched_entity_init(&ring->sched, &vm->entity,
                                  rq, amdgpu_sched_jobs);
        if (r)
                goto err;

        vm->page_directory_fence = NULL;

        r = amdgpu_bo_create(adev, pd_size, align, true,
                             AMDGPU_GEM_DOMAIN_VRAM,
                             AMDGPU_GEM_CREATE_NO_CPU_ACCESS |
                             AMDGPU_GEM_CREATE_SHADOW,
                             NULL, NULL, &vm->page_directory);
        if (r)
                goto error_free_sched_entity;

        r = amdgpu_bo_reserve(vm->page_directory, false);
        if (r)
                goto error_free_page_directory;

        r = amdgpu_vm_clear_bo(adev, vm, vm->page_directory);
        if (r)
                goto error_unreserve;

        if (vm->page_directory->shadow) {
                r = amdgpu_vm_clear_bo(adev, vm, vm->page_directory->shadow);
                if (r)
                        goto error_unreserve;
        }

        vm->last_eviction_counter = atomic64_read(&adev->num_evictions);
        amdgpu_bo_unreserve(vm->page_directory);

        return 0;

error_unreserve:
        amdgpu_bo_unreserve(vm->page_directory);

error_free_page_directory:
        amdgpu_bo_unref(&vm->page_directory->shadow);
        amdgpu_bo_unref(&vm->page_directory);
        vm->page_directory = NULL;

error_free_sched_entity:
        amd_sched_entity_fini(&ring->sched, &vm->entity);

err:
        drm_free_large(vm->page_tables);

        return r;
}

/**
 * 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;
        int i;

        amd_sched_entity_fini(vm->entity.sched, &vm->entity);

        if (!RB_EMPTY_ROOT(&vm->va)) {
                dev_err(adev->dev, "still active bo inside vm\n");
        }
        rbtree_postorder_for_each_entry_safe(mapping, tmp, &vm->va, it.rb) {
                list_del(&mapping->list);
                interval_tree_remove(&mapping->it, &vm->va);
                kfree(mapping);
        }
        list_for_each_entry_safe(mapping, tmp, &vm->freed, list) {
                list_del(&mapping->list);
                kfree(mapping);
        }

        for (i = 0; i < amdgpu_vm_num_pdes(adev); i++) {
                struct amdgpu_bo *pt = vm->page_tables[i].entry.robj;

                if (!pt)
                        continue;

                amdgpu_bo_unref(&pt->shadow);
                amdgpu_bo_unref(&pt);
        }
        drm_free_large(vm->page_tables);

        amdgpu_bo_unref(&vm->page_directory->shadow);
        amdgpu_bo_unref(&vm->page_directory);
        fence_put(vm->page_directory_fence);
}

/**
 * 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)
{
        unsigned i;

        INIT_LIST_HEAD(&adev->vm_manager.ids_lru);

        /* skip over VMID 0, since it is the system VM */
        for (i = 1; i < adev->vm_manager.num_ids; ++i) {
                amdgpu_vm_reset_id(adev, i);
                amdgpu_sync_create(&adev->vm_manager.ids[i].active);
                list_add_tail(&adev->vm_manager.ids[i].list,
                              &adev->vm_manager.ids_lru);
        }

        adev->vm_manager.fence_context = fence_context_alloc(AMDGPU_MAX_RINGS);
        for (i = 0; i < AMDGPU_MAX_RINGS; ++i)
                adev->vm_manager.seqno[i] = 0;

        atomic_set(&adev->vm_manager.vm_pte_next_ring, 0);
        atomic64_set(&adev->vm_manager.client_counter, 0);
}

/**
 * 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)
{
        unsigned i;

        for (i = 0; i < AMDGPU_NUM_VM; ++i) {
                struct amdgpu_vm_id *id = &adev->vm_manager.ids[i];

                fence_put(adev->vm_manager.ids[i].first);
                amdgpu_sync_free(&adev->vm_manager.ids[i].active);
                fence_put(id->flushed_updates);
                fence_put(id->last_flush);
        }
}