/*
 * Copyright 2008 Jerome Glisse.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * PRECISION INSIGHT AND/OR ITS SUPPLIERS 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:
 *    Jerome Glisse <glisse@freedesktop.org>
 */

#include <linux/file.h>
#include <linux/pagemap.h>
#include <linux/sync_file.h>
#include <linux/dma-buf.h>

#include <drm/amdgpu_drm.h>
#include <drm/drm_syncobj.h>
#include "amdgpu_cs.h"
#include "amdgpu.h"
#include "amdgpu_trace.h"
#include "amdgpu_gmc.h"
#include "amdgpu_gem.h"
#include "amdgpu_ras.h"

static int amdgpu_cs_user_fence_chunk(struct amdgpu_cs_parser *p,
                                      struct drm_amdgpu_cs_chunk_fence *data,
                                      uint32_t *offset)
{
        struct drm_gem_object *gobj;
        struct amdgpu_bo *bo;
        unsigned long size;
        int r;

        gobj = drm_gem_object_lookup(p->filp, data->handle);
        if (gobj == NULL)
                return -EINVAL;

        bo = amdgpu_bo_ref(gem_to_amdgpu_bo(gobj));
        p->uf_entry.priority = 0;
        p->uf_entry.tv.bo = &bo->tbo;
        /* One for TTM and one for the CS job */
        p->uf_entry.tv.num_shared = 2;

        drm_gem_object_put(gobj);

        size = amdgpu_bo_size(bo);
        if (size != PAGE_SIZE || (data->offset + 8) > size) {
                r = -EINVAL;
                goto error_unref;
        }

        if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) {
                r = -EINVAL;
                goto error_unref;
        }

        *offset = data->offset;

        return 0;

error_unref:
        amdgpu_bo_unref(&bo);
        return r;
}

static int amdgpu_cs_bo_handles_chunk(struct amdgpu_cs_parser *p,
                                      struct drm_amdgpu_bo_list_in *data)
{
        int r;
        struct drm_amdgpu_bo_list_entry *info = NULL;

        r = amdgpu_bo_create_list_entry_array(data, &info);
        if (r)
                return r;

        r = amdgpu_bo_list_create(p->adev, p->filp, info, data->bo_number,
                                  &p->bo_list);
        if (r)
                goto error_free;

        kvfree(info);
        return 0;

error_free:
        kvfree(info);

        return r;
}

static int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, union drm_amdgpu_cs *cs)
{
        struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
        struct amdgpu_vm *vm = &fpriv->vm;
        uint64_t *chunk_array_user;
        uint64_t *chunk_array;
        unsigned size, num_ibs = 0;
        uint32_t uf_offset = 0;
        int i;
        int ret;

        if (cs->in.num_chunks == 0)
                return 0;

        chunk_array = kvmalloc_array(cs->in.num_chunks, sizeof(uint64_t), GFP_KERNEL);
        if (!chunk_array)
                return -ENOMEM;

        p->ctx = amdgpu_ctx_get(fpriv, cs->in.ctx_id);
        if (!p->ctx) {
                ret = -EINVAL;
                goto free_chunk;
        }

        mutex_lock(&p->ctx->lock);

        /* skip guilty context job */
        if (atomic_read(&p->ctx->guilty) == 1) {
                ret = -ECANCELED;
                goto free_chunk;
        }

        /* get chunks */
        chunk_array_user = u64_to_user_ptr(cs->in.chunks);
        if (copy_from_user(chunk_array, chunk_array_user,
                           sizeof(uint64_t)*cs->in.num_chunks)) {
                ret = -EFAULT;
                goto free_chunk;
        }

        p->nchunks = cs->in.num_chunks;
        p->chunks = kvmalloc_array(p->nchunks, sizeof(struct amdgpu_cs_chunk),
                            GFP_KERNEL);
        if (!p->chunks) {
                ret = -ENOMEM;
                goto free_chunk;
        }

        for (i = 0; i < p->nchunks; i++) {
                struct drm_amdgpu_cs_chunk __user **chunk_ptr = NULL;
                struct drm_amdgpu_cs_chunk user_chunk;
                uint32_t __user *cdata;

                chunk_ptr = u64_to_user_ptr(chunk_array[i]);
                if (copy_from_user(&user_chunk, chunk_ptr,
                                       sizeof(struct drm_amdgpu_cs_chunk))) {
                        ret = -EFAULT;
                        i--;
                        goto free_partial_kdata;
                }
                p->chunks[i].chunk_id = user_chunk.chunk_id;
                p->chunks[i].length_dw = user_chunk.length_dw;

                size = p->chunks[i].length_dw;
                cdata = u64_to_user_ptr(user_chunk.chunk_data);

                p->chunks[i].kdata = kvmalloc_array(size, sizeof(uint32_t), GFP_KERNEL);
                if (p->chunks[i].kdata == NULL) {
                        ret = -ENOMEM;
                        i--;
                        goto free_partial_kdata;
                }
                size *= sizeof(uint32_t);
                if (copy_from_user(p->chunks[i].kdata, cdata, size)) {
                        ret = -EFAULT;
                        goto free_partial_kdata;
                }

                switch (p->chunks[i].chunk_id) {
                case AMDGPU_CHUNK_ID_IB:
                        ++num_ibs;
                        break;

                case AMDGPU_CHUNK_ID_FENCE:
                        size = sizeof(struct drm_amdgpu_cs_chunk_fence);
                        if (p->chunks[i].length_dw * sizeof(uint32_t) < size) {
                                ret = -EINVAL;
                                goto free_partial_kdata;
                        }

                        ret = amdgpu_cs_user_fence_chunk(p, p->chunks[i].kdata,
                                                         &uf_offset);
                        if (ret)
                                goto free_partial_kdata;

                        break;

                case AMDGPU_CHUNK_ID_BO_HANDLES:
                        size = sizeof(struct drm_amdgpu_bo_list_in);
                        if (p->chunks[i].length_dw * sizeof(uint32_t) < size) {
                                ret = -EINVAL;
                                goto free_partial_kdata;
                        }

                        ret = amdgpu_cs_bo_handles_chunk(p, p->chunks[i].kdata);
                        if (ret)
                                goto free_partial_kdata;

                        break;

                case AMDGPU_CHUNK_ID_DEPENDENCIES:
                case AMDGPU_CHUNK_ID_SYNCOBJ_IN:
                case AMDGPU_CHUNK_ID_SYNCOBJ_OUT:
                case AMDGPU_CHUNK_ID_SCHEDULED_DEPENDENCIES:
                case AMDGPU_CHUNK_ID_SYNCOBJ_TIMELINE_WAIT:
                case AMDGPU_CHUNK_ID_SYNCOBJ_TIMELINE_SIGNAL:
                        break;

                default:
                        ret = -EINVAL;
                        goto free_partial_kdata;
                }
        }

        ret = amdgpu_job_alloc(p->adev, num_ibs, &p->job, vm);
        if (ret)
                goto free_all_kdata;

        if (p->ctx->vram_lost_counter != p->job->vram_lost_counter) {
                ret = -ECANCELED;
                goto free_all_kdata;
        }

        if (p->uf_entry.tv.bo)
                p->job->uf_addr = uf_offset;
        kvfree(chunk_array);

        /* Use this opportunity to fill in task info for the vm */
        amdgpu_vm_set_task_info(vm);

        return 0;

free_all_kdata:
        i = p->nchunks - 1;
free_partial_kdata:
        for (; i >= 0; i--)
                kvfree(p->chunks[i].kdata);
        kvfree(p->chunks);
        p->chunks = NULL;
        p->nchunks = 0;
free_chunk:
        kvfree(chunk_array);

        return ret;
}

/* Convert microseconds to bytes. */
static u64 us_to_bytes(struct amdgpu_device *adev, s64 us)
{
        if (us <= 0 || !adev->mm_stats.log2_max_MBps)
                return 0;

        /* Since accum_us is incremented by a million per second, just
         * multiply it by the number of MB/s to get the number of bytes.
         */
        return us << adev->mm_stats.log2_max_MBps;
}

static s64 bytes_to_us(struct amdgpu_device *adev, u64 bytes)
{
        if (!adev->mm_stats.log2_max_MBps)
                return 0;

        return bytes >> adev->mm_stats.log2_max_MBps;
}

/* Returns how many bytes TTM can move right now. If no bytes can be moved,
 * it returns 0. If it returns non-zero, it's OK to move at least one buffer,
 * which means it can go over the threshold once. If that happens, the driver
 * will be in debt and no other buffer migrations can be done until that debt
 * is repaid.
 *
 * This approach allows moving a buffer of any size (it's important to allow
 * that).
 *
 * The currency is simply time in microseconds and it increases as the clock
 * ticks. The accumulated microseconds (us) are converted to bytes and
 * returned.
 */
static void amdgpu_cs_get_threshold_for_moves(struct amdgpu_device *adev,
                                              u64 *max_bytes,
                                              u64 *max_vis_bytes)
{
        s64 time_us, increment_us;
        u64 free_vram, total_vram, used_vram;
        /* Allow a maximum of 200 accumulated ms. This is basically per-IB
         * throttling.
         *
         * It means that in order to get full max MBps, at least 5 IBs per
         * second must be submitted and not more than 200ms apart from each
         * other.
         */
        const s64 us_upper_bound = 200000;

        if (!adev->mm_stats.log2_max_MBps) {
                *max_bytes = 0;
                *max_vis_bytes = 0;
                return;
        }

        total_vram = adev->gmc.real_vram_size - atomic64_read(&adev->vram_pin_size);
        used_vram = ttm_resource_manager_usage(&adev->mman.vram_mgr.manager);
        free_vram = used_vram >= total_vram ? 0 : total_vram - used_vram;

        spin_lock(&adev->mm_stats.lock);

        /* Increase the amount of accumulated us. */
        time_us = ktime_to_us(ktime_get());
        increment_us = time_us - adev->mm_stats.last_update_us;
        adev->mm_stats.last_update_us = time_us;
        adev->mm_stats.accum_us = min(adev->mm_stats.accum_us + increment_us,
                                      us_upper_bound);

        /* This prevents the short period of low performance when the VRAM
         * usage is low and the driver is in debt or doesn't have enough
         * accumulated us to fill VRAM quickly.
         *
         * The situation can occur in these cases:
         * - a lot of VRAM is freed by userspace
         * - the presence of a big buffer causes a lot of evictions
         *   (solution: split buffers into smaller ones)
         *
         * If 128 MB or 1/8th of VRAM is free, start filling it now by setting
         * accum_us to a positive number.
         */
        if (free_vram >= 128 * 1024 * 1024 || free_vram >= total_vram / 8) {
                s64 min_us;

                /* Be more aggressive on dGPUs. Try to fill a portion of free
                 * VRAM now.
                 */
                if (!(adev->flags & AMD_IS_APU))
                        min_us = bytes_to_us(adev, free_vram / 4);
                else
                        min_us = 0; /* Reset accum_us on APUs. */

                adev->mm_stats.accum_us = max(min_us, adev->mm_stats.accum_us);
        }

        /* This is set to 0 if the driver is in debt to disallow (optional)
         * buffer moves.
         */
        *max_bytes = us_to_bytes(adev, adev->mm_stats.accum_us);

        /* Do the same for visible VRAM if half of it is free */
        if (!amdgpu_gmc_vram_full_visible(&adev->gmc)) {
                u64 total_vis_vram = adev->gmc.visible_vram_size;
                u64 used_vis_vram =
                  amdgpu_vram_mgr_vis_usage(&adev->mman.vram_mgr);

                if (used_vis_vram < total_vis_vram) {
                        u64 free_vis_vram = total_vis_vram - used_vis_vram;
                        adev->mm_stats.accum_us_vis = min(adev->mm_stats.accum_us_vis +
                                                          increment_us, us_upper_bound);

                        if (free_vis_vram >= total_vis_vram / 2)
                                adev->mm_stats.accum_us_vis =
                                        max(bytes_to_us(adev, free_vis_vram / 2),
                                            adev->mm_stats.accum_us_vis);
                }

                *max_vis_bytes = us_to_bytes(adev, adev->mm_stats.accum_us_vis);
        } else {
                *max_vis_bytes = 0;
        }

        spin_unlock(&adev->mm_stats.lock);
}

/* Report how many bytes have really been moved for the last command
 * submission. This can result in a debt that can stop buffer migrations
 * temporarily.
 */
void amdgpu_cs_report_moved_bytes(struct amdgpu_device *adev, u64 num_bytes,
                                  u64 num_vis_bytes)
{
        spin_lock(&adev->mm_stats.lock);
        adev->mm_stats.accum_us -= bytes_to_us(adev, num_bytes);
        adev->mm_stats.accum_us_vis -= bytes_to_us(adev, num_vis_bytes);
        spin_unlock(&adev->mm_stats.lock);
}

static int amdgpu_cs_bo_validate(void *param, struct amdgpu_bo *bo)
{
        struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
        struct amdgpu_cs_parser *p = param;
        struct ttm_operation_ctx ctx = {
                .interruptible = true,
                .no_wait_gpu = false,
                .resv = bo->tbo.base.resv
        };
        uint32_t domain;
        int r;

        if (bo->tbo.pin_count)
                return 0;

        /* Don't move this buffer if we have depleted our allowance
         * to move it. Don't move anything if the threshold is zero.
         */
        if (p->bytes_moved < p->bytes_moved_threshold &&
            (!bo->tbo.base.dma_buf ||
            list_empty(&bo->tbo.base.dma_buf->attachments))) {
                if (!amdgpu_gmc_vram_full_visible(&adev->gmc) &&
                    (bo->flags & AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED)) {
                        /* And don't move a CPU_ACCESS_REQUIRED BO to limited
                         * visible VRAM if we've depleted our allowance to do
                         * that.
                         */
                        if (p->bytes_moved_vis < p->bytes_moved_vis_threshold)
                                domain = bo->preferred_domains;
                        else
                                domain = bo->allowed_domains;
                } else {
                        domain = bo->preferred_domains;
                }
        } else {
                domain = bo->allowed_domains;
        }

retry:
        amdgpu_bo_placement_from_domain(bo, domain);
        r = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);

        p->bytes_moved += ctx.bytes_moved;
        if (!amdgpu_gmc_vram_full_visible(&adev->gmc) &&
            amdgpu_bo_in_cpu_visible_vram(bo))
                p->bytes_moved_vis += ctx.bytes_moved;

        if (unlikely(r == -ENOMEM) && domain != bo->allowed_domains) {
                domain = bo->allowed_domains;
                goto retry;
        }

        return r;
}

static int amdgpu_cs_list_validate(struct amdgpu_cs_parser *p,
                            struct list_head *validated)
{
        struct ttm_operation_ctx ctx = { true, false };
        struct amdgpu_bo_list_entry *lobj;
        int r;

        list_for_each_entry(lobj, validated, tv.head) {
                struct amdgpu_bo *bo = ttm_to_amdgpu_bo(lobj->tv.bo);
                struct mm_struct *usermm;

                usermm = amdgpu_ttm_tt_get_usermm(bo->tbo.ttm);
                if (usermm && usermm != current->mm)
                        return -EPERM;

                if (amdgpu_ttm_tt_is_userptr(bo->tbo.ttm) &&
                    lobj->user_invalidated && lobj->user_pages) {
                        amdgpu_bo_placement_from_domain(bo,
                                                        AMDGPU_GEM_DOMAIN_CPU);
                        r = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
                        if (r)
                                return r;

                        amdgpu_ttm_tt_set_user_pages(bo->tbo.ttm,
                                                     lobj->user_pages);
                }

                r = amdgpu_cs_bo_validate(p, bo);
                if (r)
                        return r;

                kvfree(lobj->user_pages);
                lobj->user_pages = NULL;
        }
        return 0;
}

static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
                                union drm_amdgpu_cs *cs)
{
        struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
        struct amdgpu_vm *vm = &fpriv->vm;
        struct amdgpu_bo_list_entry *e;
        struct list_head duplicates;
        struct amdgpu_bo *gds;
        struct amdgpu_bo *gws;
        struct amdgpu_bo *oa;
        int r;

        INIT_LIST_HEAD(&p->validated);

        /* p->bo_list could already be assigned if AMDGPU_CHUNK_ID_BO_HANDLES is present */
        if (cs->in.bo_list_handle) {
                if (p->bo_list)
                        return -EINVAL;

                r = amdgpu_bo_list_get(fpriv, cs->in.bo_list_handle,
                                       &p->bo_list);
                if (r)
                        return r;
        } else if (!p->bo_list) {
                /* Create a empty bo_list when no handle is provided */
                r = amdgpu_bo_list_create(p->adev, p->filp, NULL, 0,
                                          &p->bo_list);
                if (r)
                        return r;
        }

        /* One for TTM and one for the CS job */
        amdgpu_bo_list_for_each_entry(e, p->bo_list)
                e->tv.num_shared = 2;

        amdgpu_bo_list_get_list(p->bo_list, &p->validated);

        INIT_LIST_HEAD(&duplicates);
        amdgpu_vm_get_pd_bo(&fpriv->vm, &p->validated, &p->vm_pd);

        if (p->uf_entry.tv.bo && !ttm_to_amdgpu_bo(p->uf_entry.tv.bo)->parent)
                list_add(&p->uf_entry.tv.head, &p->validated);

        /* Get userptr backing pages. If pages are updated after registered
         * in amdgpu_gem_userptr_ioctl(), amdgpu_cs_list_validate() will do
         * amdgpu_ttm_backend_bind() to flush and invalidate new pages
         */
        amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
                struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);
                bool userpage_invalidated = false;
                int i;

                e->user_pages = kvmalloc_array(bo->tbo.ttm->num_pages,
                                        sizeof(struct page *),
                                        GFP_KERNEL | __GFP_ZERO);
                if (!e->user_pages) {
                        DRM_ERROR("kvmalloc_array failure\n");
                        return -ENOMEM;
                }

                r = amdgpu_ttm_tt_get_user_pages(bo, e->user_pages);
                if (r) {
                        kvfree(e->user_pages);
                        e->user_pages = NULL;
                        return r;
                }

                for (i = 0; i < bo->tbo.ttm->num_pages; i++) {
                        if (bo->tbo.ttm->pages[i] != e->user_pages[i]) {
                                userpage_invalidated = true;
                                break;
                        }
                }
                e->user_invalidated = userpage_invalidated;
        }

        r = ttm_eu_reserve_buffers(&p->ticket, &p->validated, true,
                                   &duplicates);
        if (unlikely(r != 0)) {
                if (r != -ERESTARTSYS)
                        DRM_ERROR("ttm_eu_reserve_buffers failed.\n");
                goto out;
        }

        amdgpu_bo_list_for_each_entry(e, p->bo_list) {
                struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);

                e->bo_va = amdgpu_vm_bo_find(vm, bo);

                if (bo->tbo.base.dma_buf && !amdgpu_bo_explicit_sync(bo)) {
                        e->chain = dma_fence_chain_alloc();
                        if (!e->chain) {
                                r = -ENOMEM;
                                goto error_validate;
                        }
                }
        }

        /* Move fence waiting after getting reservation lock of
         * PD root. Then there is no need on a ctx mutex lock.
         */
        r = amdgpu_ctx_wait_prev_fence(p->ctx, p->entity);
        if (unlikely(r != 0)) {
                if (r != -ERESTARTSYS)
                        DRM_ERROR("amdgpu_ctx_wait_prev_fence failed.\n");
                goto error_validate;
        }

        amdgpu_cs_get_threshold_for_moves(p->adev, &p->bytes_moved_threshold,
                                          &p->bytes_moved_vis_threshold);
        p->bytes_moved = 0;
        p->bytes_moved_vis = 0;

        r = amdgpu_vm_validate_pt_bos(p->adev, &fpriv->vm,
                                      amdgpu_cs_bo_validate, p);
        if (r) {
                DRM_ERROR("amdgpu_vm_validate_pt_bos() failed.\n");
                goto error_validate;
        }

        r = amdgpu_cs_list_validate(p, &duplicates);
        if (r)
                goto error_validate;

        r = amdgpu_cs_list_validate(p, &p->validated);
        if (r)
                goto error_validate;

        amdgpu_cs_report_moved_bytes(p->adev, p->bytes_moved,
                                     p->bytes_moved_vis);

        gds = p->bo_list->gds_obj;
        gws = p->bo_list->gws_obj;
        oa = p->bo_list->oa_obj;

        if (gds) {
                p->job->gds_base = amdgpu_bo_gpu_offset(gds) >> PAGE_SHIFT;
                p->job->gds_size = amdgpu_bo_size(gds) >> PAGE_SHIFT;
        }
        if (gws) {
                p->job->gws_base = amdgpu_bo_gpu_offset(gws) >> PAGE_SHIFT;
                p->job->gws_size = amdgpu_bo_size(gws) >> PAGE_SHIFT;
        }
        if (oa) {
                p->job->oa_base = amdgpu_bo_gpu_offset(oa) >> PAGE_SHIFT;
                p->job->oa_size = amdgpu_bo_size(oa) >> PAGE_SHIFT;
        }

        if (!r && p->uf_entry.tv.bo) {
                struct amdgpu_bo *uf = ttm_to_amdgpu_bo(p->uf_entry.tv.bo);

                r = amdgpu_ttm_alloc_gart(&uf->tbo);
                p->job->uf_addr += amdgpu_bo_gpu_offset(uf);
        }

error_validate:
        if (r) {
                amdgpu_bo_list_for_each_entry(e, p->bo_list) {
                        dma_fence_chain_free(e->chain);
                        e->chain = NULL;
                }
                ttm_eu_backoff_reservation(&p->ticket, &p->validated);
        }
out:
        return r;
}

static int amdgpu_cs_sync_rings(struct amdgpu_cs_parser *p)
{
        struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
        struct amdgpu_bo_list_entry *e;
        int r;

        list_for_each_entry(e, &p->validated, tv.head) {
                struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);
                struct dma_resv *resv = bo->tbo.base.resv;
                enum amdgpu_sync_mode sync_mode;

                sync_mode = amdgpu_bo_explicit_sync(bo) ?
                        AMDGPU_SYNC_EXPLICIT : AMDGPU_SYNC_NE_OWNER;
                r = amdgpu_sync_resv(p->adev, &p->job->sync, resv, sync_mode,
                                     &fpriv->vm);
                if (r)
                        return r;
        }
        return 0;
}

/**
 * amdgpu_cs_parser_fini() - clean parser states
 * @parser:     parser structure holding parsing context.
 * @error:      error number
 * @backoff:    indicator to backoff the reservation
 *
 * If error is set then unvalidate buffer, otherwise just free memory
 * used by parsing context.
 **/
static void amdgpu_cs_parser_fini(struct amdgpu_cs_parser *parser, int error,
                                  bool backoff)
{
        unsigned i;

        if (error && backoff) {
                struct amdgpu_bo_list_entry *e;

                amdgpu_bo_list_for_each_entry(e, parser->bo_list) {
                        dma_fence_chain_free(e->chain);
                        e->chain = NULL;
                }

                ttm_eu_backoff_reservation(&parser->ticket,
                                           &parser->validated);
        }

        for (i = 0; i < parser->num_post_deps; i++) {
                drm_syncobj_put(parser->post_deps[i].syncobj);
                kfree(parser->post_deps[i].chain);
        }
        kfree(parser->post_deps);

        dma_fence_put(parser->fence);

        if (parser->ctx) {
                mutex_unlock(&parser->ctx->lock);
                amdgpu_ctx_put(parser->ctx);
        }
        if (parser->bo_list)
                amdgpu_bo_list_put(parser->bo_list);

        for (i = 0; i < parser->nchunks; i++)
                kvfree(parser->chunks[i].kdata);
        kvfree(parser->chunks);
        if (parser->job)
                amdgpu_job_free(parser->job);
        if (parser->uf_entry.tv.bo) {
                struct amdgpu_bo *uf = ttm_to_amdgpu_bo(parser->uf_entry.tv.bo);

                amdgpu_bo_unref(&uf);
        }
}

static int amdgpu_cs_vm_handling(struct amdgpu_cs_parser *p)
{
        struct amdgpu_ring *ring = to_amdgpu_ring(p->entity->rq->sched);
        struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
        struct amdgpu_device *adev = p->adev;
        struct amdgpu_vm *vm = &fpriv->vm;
        struct amdgpu_bo_list_entry *e;
        struct amdgpu_bo_va *bo_va;
        struct amdgpu_bo *bo;
        int r;

        /* Only for UVD/VCE VM emulation */
        if (ring->funcs->parse_cs || ring->funcs->patch_cs_in_place) {
                unsigned i, j;

                for (i = 0, j = 0; i < p->nchunks && j < p->job->num_ibs; i++) {
                        struct drm_amdgpu_cs_chunk_ib *chunk_ib;
                        struct amdgpu_bo_va_mapping *m;
                        struct amdgpu_bo *aobj = NULL;
                        struct amdgpu_cs_chunk *chunk;
                        uint64_t offset, va_start;
                        struct amdgpu_ib *ib;
                        uint8_t *kptr;

                        chunk = &p->chunks[i];
                        ib = &p->job->ibs[j];
                        chunk_ib = chunk->kdata;

                        if (chunk->chunk_id != AMDGPU_CHUNK_ID_IB)
                                continue;

                        va_start = chunk_ib->va_start & AMDGPU_GMC_HOLE_MASK;
                        r = amdgpu_cs_find_mapping(p, va_start, &aobj, &m);
                        if (r) {
                                DRM_ERROR("IB va_start is invalid\n");
                                return r;
                        }

                        if ((va_start + chunk_ib->ib_bytes) >
                            (m->last + 1) * AMDGPU_GPU_PAGE_SIZE) {
                                DRM_ERROR("IB va_start+ib_bytes is invalid\n");
                                return -EINVAL;
                        }

                        /* the IB should be reserved at this point */
                        r = amdgpu_bo_kmap(aobj, (void **)&kptr);
                        if (r) {
                                return r;
                        }

                        offset = m->start * AMDGPU_GPU_PAGE_SIZE;
                        kptr += va_start - offset;

                        if (ring->funcs->parse_cs) {
                                memcpy(ib->ptr, kptr, chunk_ib->ib_bytes);
                                amdgpu_bo_kunmap(aobj);

                                r = amdgpu_ring_parse_cs(ring, p, p->job, ib);
                                if (r)
                                        return r;
                        } else {
                                ib->ptr = (uint32_t *)kptr;
                                r = amdgpu_ring_patch_cs_in_place(ring, p, p->job, ib);
                                amdgpu_bo_kunmap(aobj);
                                if (r)
                                        return r;
                        }

                        j++;
                }
        }

        if (!p->job->vm)
                return amdgpu_cs_sync_rings(p);


        r = amdgpu_vm_clear_freed(adev, vm, NULL);
        if (r)
                return r;

        r = amdgpu_vm_bo_update(adev, fpriv->prt_va, false, NULL);
        if (r)
                return r;

        r = amdgpu_sync_vm_fence(&p->job->sync, fpriv->prt_va->last_pt_update);
        if (r)
                return r;

        if (amdgpu_mcbp || amdgpu_sriov_vf(adev)) {
                bo_va = fpriv->csa_va;
                BUG_ON(!bo_va);
                r = amdgpu_vm_bo_update(adev, bo_va, false, NULL);
                if (r)
                        return r;

                r = amdgpu_sync_vm_fence(&p->job->sync, bo_va->last_pt_update);
                if (r)
                        return r;
        }

        amdgpu_bo_list_for_each_entry(e, p->bo_list) {
                /* ignore duplicates */
                bo = ttm_to_amdgpu_bo(e->tv.bo);
                if (!bo)
                        continue;

                bo_va = e->bo_va;
                if (bo_va == NULL)
                        continue;

                r = amdgpu_vm_bo_update(adev, bo_va, false, NULL);
                if (r)
                        return r;

                r = amdgpu_sync_vm_fence(&p->job->sync, bo_va->last_pt_update);
                if (r)
                        return r;
        }

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

        r = amdgpu_vm_update_pdes(adev, vm, false);
        if (r)
                return r;

        r = amdgpu_sync_vm_fence(&p->job->sync, vm->last_update);
        if (r)
                return r;

        p->job->vm_pd_addr = amdgpu_gmc_pd_addr(vm->root.bo);

        if (amdgpu_vm_debug) {
                /* Invalidate all BOs to test for userspace bugs */
                amdgpu_bo_list_for_each_entry(e, p->bo_list) {
                        struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);

                        /* ignore duplicates */
                        if (!bo)
                                continue;

                        amdgpu_vm_bo_invalidate(adev, bo, false);
                }
        }

        return amdgpu_cs_sync_rings(p);
}

static int amdgpu_cs_ib_fill(struct amdgpu_device *adev,
                             struct amdgpu_cs_parser *parser)
{
        struct amdgpu_fpriv *fpriv = parser->filp->driver_priv;
        struct amdgpu_vm *vm = &fpriv->vm;
        int r, ce_preempt = 0, de_preempt = 0;
        struct amdgpu_ring *ring;
        int i, j;

        for (i = 0, j = 0; i < parser->nchunks && j < parser->job->num_ibs; i++) {
                struct amdgpu_cs_chunk *chunk;
                struct amdgpu_ib *ib;
                struct drm_amdgpu_cs_chunk_ib *chunk_ib;
                struct drm_sched_entity *entity;

                chunk = &parser->chunks[i];
                ib = &parser->job->ibs[j];
                chunk_ib = (struct drm_amdgpu_cs_chunk_ib *)chunk->kdata;

                if (chunk->chunk_id != AMDGPU_CHUNK_ID_IB)
                        continue;

                if (chunk_ib->ip_type == AMDGPU_HW_IP_GFX &&
                    (amdgpu_mcbp || amdgpu_sriov_vf(adev))) {
                        if (chunk_ib->flags & AMDGPU_IB_FLAG_PREEMPT) {
                                if (chunk_ib->flags & AMDGPU_IB_FLAG_CE)
                                        ce_preempt++;
                                else
                                        de_preempt++;
                        }

                        /* each GFX command submit allows 0 or 1 IB preemptible for CE & DE */
                        if (ce_preempt > 1 || de_preempt > 1)
                                return -EINVAL;
                }

                r = amdgpu_ctx_get_entity(parser->ctx, chunk_ib->ip_type,
                                          chunk_ib->ip_instance, chunk_ib->ring,
                                          &entity);
                if (r)
                        return r;

                if (chunk_ib->flags & AMDGPU_IB_FLAG_PREAMBLE)
                        parser->job->preamble_status |=
                                AMDGPU_PREAMBLE_IB_PRESENT;

                if (parser->entity && parser->entity != entity)
                        return -EINVAL;

                /* Return if there is no run queue associated with this entity.
                 * Possibly because of disabled HW IP*/
                if (entity->rq == NULL)
                        return -EINVAL;

                parser->entity = entity;

                ring = to_amdgpu_ring(entity->rq->sched);
                r =  amdgpu_ib_get(adev, vm, ring->funcs->parse_cs ?
                                   chunk_ib->ib_bytes : 0,
                                   AMDGPU_IB_POOL_DELAYED, ib);
                if (r) {
                        DRM_ERROR("Failed to get ib !\n");
                        return r;
                }

                ib->gpu_addr = chunk_ib->va_start;
                ib->length_dw = chunk_ib->ib_bytes / 4;
                ib->flags = chunk_ib->flags;

                j++;
        }

        /* MM engine doesn't support user fences */
        ring = to_amdgpu_ring(parser->entity->rq->sched);
        if (parser->job->uf_addr && ring->funcs->no_user_fence)
                return -EINVAL;

        return 0;
}

static int amdgpu_cs_process_fence_dep(struct amdgpu_cs_parser *p,
                                       struct amdgpu_cs_chunk *chunk)
{
        struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
        unsigned num_deps;
        int i, r;
        struct drm_amdgpu_cs_chunk_dep *deps;

        deps = (struct drm_amdgpu_cs_chunk_dep *)chunk->kdata;
        num_deps = chunk->length_dw * 4 /
                sizeof(struct drm_amdgpu_cs_chunk_dep);

        for (i = 0; i < num_deps; ++i) {
                struct amdgpu_ctx *ctx;
                struct drm_sched_entity *entity;
                struct dma_fence *fence;

                ctx = amdgpu_ctx_get(fpriv, deps[i].ctx_id);
                if (ctx == NULL)
                        return -EINVAL;

                r = amdgpu_ctx_get_entity(ctx, deps[i].ip_type,
                                          deps[i].ip_instance,
                                          deps[i].ring, &entity);
                if (r) {
                        amdgpu_ctx_put(ctx);
                        return r;
                }

                fence = amdgpu_ctx_get_fence(ctx, entity, deps[i].handle);
                amdgpu_ctx_put(ctx);

                if (IS_ERR(fence))
                        return PTR_ERR(fence);
                else if (!fence)
                        continue;

                if (chunk->chunk_id == AMDGPU_CHUNK_ID_SCHEDULED_DEPENDENCIES) {
                        struct drm_sched_fence *s_fence;
                        struct dma_fence *old = fence;

                        s_fence = to_drm_sched_fence(fence);
                        fence = dma_fence_get(&s_fence->scheduled);
                        dma_fence_put(old);
                }

                r = amdgpu_sync_fence(&p->job->sync, fence);
                dma_fence_put(fence);
                if (r)
                        return r;
        }
        return 0;
}

static int amdgpu_syncobj_lookup_and_add_to_sync(struct amdgpu_cs_parser *p,
                                                 uint32_t handle, u64 point,
                                                 u64 flags)
{
        struct dma_fence *fence;
        int r;

        r = drm_syncobj_find_fence(p->filp, handle, point, flags, &fence);
        if (r) {
                DRM_ERROR("syncobj %u failed to find fence @ %llu (%d)!\n",
                          handle, point, r);
                return r;
        }

        r = amdgpu_sync_fence(&p->job->sync, fence);
        dma_fence_put(fence);

        return r;
}

static int amdgpu_cs_process_syncobj_in_dep(struct amdgpu_cs_parser *p,
                                            struct amdgpu_cs_chunk *chunk)
{
        struct drm_amdgpu_cs_chunk_sem *deps;
        unsigned num_deps;
        int i, r;

        deps = (struct drm_amdgpu_cs_chunk_sem *)chunk->kdata;
        num_deps = chunk->length_dw * 4 /
                sizeof(struct drm_amdgpu_cs_chunk_sem);
        for (i = 0; i < num_deps; ++i) {
                r = amdgpu_syncobj_lookup_and_add_to_sync(p, deps[i].handle,
                                                          0, 0);
                if (r)
                        return r;
        }

        return 0;
}


static int amdgpu_cs_process_syncobj_timeline_in_dep(struct amdgpu_cs_parser *p,
                                                     struct amdgpu_cs_chunk *chunk)
{
        struct drm_amdgpu_cs_chunk_syncobj *syncobj_deps;
        unsigned num_deps;
        int i, r;

        syncobj_deps = (struct drm_amdgpu_cs_chunk_syncobj *)chunk->kdata;
        num_deps = chunk->length_dw * 4 /
                sizeof(struct drm_amdgpu_cs_chunk_syncobj);
        for (i = 0; i < num_deps; ++i) {
                r = amdgpu_syncobj_lookup_and_add_to_sync(p,
                                                          syncobj_deps[i].handle,
                                                          syncobj_deps[i].point,
                                                          syncobj_deps[i].flags);
                if (r)
                        return r;
        }

        return 0;
}

static int amdgpu_cs_process_syncobj_out_dep(struct amdgpu_cs_parser *p,
                                             struct amdgpu_cs_chunk *chunk)
{
        struct drm_amdgpu_cs_chunk_sem *deps;
        unsigned num_deps;
        int i;

        deps = (struct drm_amdgpu_cs_chunk_sem *)chunk->kdata;
        num_deps = chunk->length_dw * 4 /
                sizeof(struct drm_amdgpu_cs_chunk_sem);

        if (p->post_deps)
                return -EINVAL;

        p->post_deps = kmalloc_array(num_deps, sizeof(*p->post_deps),
                                     GFP_KERNEL);
        p->num_post_deps = 0;

        if (!p->post_deps)
                return -ENOMEM;


        for (i = 0; i < num_deps; ++i) {
                p->post_deps[i].syncobj =
                        drm_syncobj_find(p->filp, deps[i].handle);
                if (!p->post_deps[i].syncobj)
                        return -EINVAL;
                p->post_deps[i].chain = NULL;
                p->post_deps[i].point = 0;
                p->num_post_deps++;
        }

        return 0;
}


static int amdgpu_cs_process_syncobj_timeline_out_dep(struct amdgpu_cs_parser *p,
                                                      struct amdgpu_cs_chunk *chunk)
{
        struct drm_amdgpu_cs_chunk_syncobj *syncobj_deps;
        unsigned num_deps;
        int i;

        syncobj_deps = (struct drm_amdgpu_cs_chunk_syncobj *)chunk->kdata;
        num_deps = chunk->length_dw * 4 /
                sizeof(struct drm_amdgpu_cs_chunk_syncobj);

        if (p->post_deps)
                return -EINVAL;

        p->post_deps = kmalloc_array(num_deps, sizeof(*p->post_deps),
                                     GFP_KERNEL);
        p->num_post_deps = 0;

        if (!p->post_deps)
                return -ENOMEM;

        for (i = 0; i < num_deps; ++i) {
                struct amdgpu_cs_post_dep *dep = &p->post_deps[i];

                dep->chain = NULL;
                if (syncobj_deps[i].point) {
                        dep->chain = dma_fence_chain_alloc();
                        if (!dep->chain)
                                return -ENOMEM;
                }

                dep->syncobj = drm_syncobj_find(p->filp,
                                                syncobj_deps[i].handle);
                if (!dep->syncobj) {
                        dma_fence_chain_free(dep->chain);
                        return -EINVAL;
                }
                dep->point = syncobj_deps[i].point;
                p->num_post_deps++;
        }

        return 0;
}

static int amdgpu_cs_dependencies(struct amdgpu_device *adev,
                                  struct amdgpu_cs_parser *p)
{
        int i, r;

        /* TODO: Investigate why we still need the context lock */
        mutex_unlock(&p->ctx->lock);

        for (i = 0; i < p->nchunks; ++i) {
                struct amdgpu_cs_chunk *chunk;

                chunk = &p->chunks[i];

                switch (chunk->chunk_id) {
                case AMDGPU_CHUNK_ID_DEPENDENCIES:
                case AMDGPU_CHUNK_ID_SCHEDULED_DEPENDENCIES:
                        r = amdgpu_cs_process_fence_dep(p, chunk);
                        if (r)
                                goto out;
                        break;
                case AMDGPU_CHUNK_ID_SYNCOBJ_IN:
                        r = amdgpu_cs_process_syncobj_in_dep(p, chunk);
                        if (r)
                                goto out;
                        break;
                case AMDGPU_CHUNK_ID_SYNCOBJ_OUT:
                        r = amdgpu_cs_process_syncobj_out_dep(p, chunk);
                        if (r)
                                goto out;
                        break;
                case AMDGPU_CHUNK_ID_SYNCOBJ_TIMELINE_WAIT:
                        r = amdgpu_cs_process_syncobj_timeline_in_dep(p, chunk);
                        if (r)
                                goto out;
                        break;
                case AMDGPU_CHUNK_ID_SYNCOBJ_TIMELINE_SIGNAL:
                        r = amdgpu_cs_process_syncobj_timeline_out_dep(p, chunk);
                        if (r)
                                goto out;
                        break;
                }
        }

out:
        mutex_lock(&p->ctx->lock);
        return r;
}

static void amdgpu_cs_post_dependencies(struct amdgpu_cs_parser *p)
{
        int i;

        for (i = 0; i < p->num_post_deps; ++i) {
                if (p->post_deps[i].chain && p->post_deps[i].point) {
                        drm_syncobj_add_point(p->post_deps[i].syncobj,
                                              p->post_deps[i].chain,
                                              p->fence, p->post_deps[i].point);
                        p->post_deps[i].chain = NULL;
                } else {
                        drm_syncobj_replace_fence(p->post_deps[i].syncobj,
                                                  p->fence);
                }
        }
}

static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
                            union drm_amdgpu_cs *cs)
{
        struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
        struct drm_sched_entity *entity = p->entity;
        struct amdgpu_bo_list_entry *e;
        struct amdgpu_job *job;
        uint64_t seq;
        int r;

        job = p->job;
        p->job = NULL;

        r = drm_sched_job_init(&job->base, entity, &fpriv->vm);
        if (r)
                goto error_unlock;

        drm_sched_job_arm(&job->base);

        /* No memory allocation is allowed while holding the notifier lock.
         * The lock is held until amdgpu_cs_submit is finished and fence is
         * added to BOs.
         */
        mutex_lock(&p->adev->notifier_lock);

        /* If userptr are invalidated after amdgpu_cs_parser_bos(), return
         * -EAGAIN, drmIoctl in libdrm will restart the amdgpu_cs_ioctl.
         */
        amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
                struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);

                r |= !amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
        }
        if (r) {
                r = -EAGAIN;
                goto error_abort;
        }

        p->fence = dma_fence_get(&job->base.s_fence->finished);

        amdgpu_ctx_add_fence(p->ctx, entity, p->fence, &seq);
        amdgpu_cs_post_dependencies(p);

        if ((job->preamble_status & AMDGPU_PREAMBLE_IB_PRESENT) &&
            !p->ctx->preamble_presented) {
                job->preamble_status |= AMDGPU_PREAMBLE_IB_PRESENT_FIRST;
                p->ctx->preamble_presented = true;
        }

        cs->out.handle = seq;
        job->uf_sequence = seq;

        amdgpu_job_free_resources(job);

        trace_amdgpu_cs_ioctl(job);
        amdgpu_vm_bo_trace_cs(&fpriv->vm, &p->ticket);
        drm_sched_entity_push_job(&job->base);

        amdgpu_vm_move_to_lru_tail(p->adev, &fpriv->vm);

        amdgpu_bo_list_for_each_entry(e, p->bo_list) {
                struct dma_resv *resv = e->tv.bo->base.resv;
                struct dma_fence_chain *chain = e->chain;

                if (!chain)
                        continue;

                /*
                 * Work around dma_resv shortcomings by wrapping up the
                 * submission in a dma_fence_chain and add it as exclusive
                 * fence.
                 */
                dma_fence_chain_init(chain, dma_resv_excl_fence(resv),
                                     dma_fence_get(p->fence), 1);

                rcu_assign_pointer(resv->fence_excl, &chain->base);
                e->chain = NULL;
        }

        ttm_eu_fence_buffer_objects(&p->ticket, &p->validated, p->fence);
        mutex_unlock(&p->adev->notifier_lock);

        return 0;

error_abort:
        drm_sched_job_cleanup(&job->base);
        mutex_unlock(&p->adev->notifier_lock);

error_unlock:
        amdgpu_job_free(job);
        return r;
}

static void trace_amdgpu_cs_ibs(struct amdgpu_cs_parser *parser)
{
        int i;

        if (!trace_amdgpu_cs_enabled())
                return;

        for (i = 0; i < parser->job->num_ibs; i++)
                trace_amdgpu_cs(parser, i);
}

int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
{
        struct amdgpu_device *adev = drm_to_adev(dev);
        union drm_amdgpu_cs *cs = data;
        struct amdgpu_cs_parser parser = {};
        bool reserved_buffers = false;
        int r;

        if (amdgpu_ras_intr_triggered())
                return -EHWPOISON;

        if (!adev->accel_working)
                return -EBUSY;

        parser.adev = adev;
        parser.filp = filp;

        r = amdgpu_cs_parser_init(&parser, data);
        if (r) {
                if (printk_ratelimit())
                        DRM_ERROR("Failed to initialize parser %d!\n", r);
                goto out;
        }

        r = amdgpu_cs_ib_fill(adev, &parser);
        if (r)
                goto out;

        r = amdgpu_cs_dependencies(adev, &parser);
        if (r) {
                DRM_ERROR("Failed in the dependencies handling %d!\n", r);
                goto out;
        }

        r = amdgpu_cs_parser_bos(&parser, data);
        if (r) {
                if (r == -ENOMEM)
                        DRM_ERROR("Not enough memory for command submission!\n");
                else if (r != -ERESTARTSYS && r != -EAGAIN)
                        DRM_ERROR("Failed to process the buffer list %d!\n", r);
                goto out;
        }

        reserved_buffers = true;

        trace_amdgpu_cs_ibs(&parser);

        r = amdgpu_cs_vm_handling(&parser);
        if (r)
                goto out;

        r = amdgpu_cs_submit(&parser, cs);

out:
        amdgpu_cs_parser_fini(&parser, r, reserved_buffers);

        return r;
}

/**
 * amdgpu_cs_wait_ioctl - wait for a command submission to finish
 *
 * @dev: drm device
 * @data: data from userspace
 * @filp: file private
 *
 * Wait for the command submission identified by handle to finish.
 */
int amdgpu_cs_wait_ioctl(struct drm_device *dev, void *data,
                         struct drm_file *filp)
{
        union drm_amdgpu_wait_cs *wait = data;
        unsigned long timeout = amdgpu_gem_timeout(wait->in.timeout);
        struct drm_sched_entity *entity;
        struct amdgpu_ctx *ctx;
        struct dma_fence *fence;
        long r;

        ctx = amdgpu_ctx_get(filp->driver_priv, wait->in.ctx_id);
        if (ctx == NULL)
                return -EINVAL;

        r = amdgpu_ctx_get_entity(ctx, wait->in.ip_type, wait->in.ip_instance,
                                  wait->in.ring, &entity);
        if (r) {
                amdgpu_ctx_put(ctx);
                return r;
        }

        fence = amdgpu_ctx_get_fence(ctx, entity, wait->in.handle);
        if (IS_ERR(fence))
                r = PTR_ERR(fence);
        else if (fence) {
                r = dma_fence_wait_timeout(fence, true, timeout);
                if (r > 0 && fence->error)
                        r = fence->error;
                dma_fence_put(fence);
        } else
                r = 1;

        amdgpu_ctx_put(ctx);
        if (r < 0)
                return r;

        memset(wait, 0, sizeof(*wait));
        wait->out.status = (r == 0);

        return 0;
}

/**
 * amdgpu_cs_get_fence - helper to get fence from drm_amdgpu_fence
 *
 * @adev: amdgpu device
 * @filp: file private
 * @user: drm_amdgpu_fence copied from user space
 */
static struct dma_fence *amdgpu_cs_get_fence(struct amdgpu_device *adev,
                                             struct drm_file *filp,
                                             struct drm_amdgpu_fence *user)
{
        struct drm_sched_entity *entity;
        struct amdgpu_ctx *ctx;
        struct dma_fence *fence;
        int r;

        ctx = amdgpu_ctx_get(filp->driver_priv, user->ctx_id);
        if (ctx == NULL)
                return ERR_PTR(-EINVAL);

        r = amdgpu_ctx_get_entity(ctx, user->ip_type, user->ip_instance,
                                  user->ring, &entity);
        if (r) {
                amdgpu_ctx_put(ctx);
                return ERR_PTR(r);
        }

        fence = amdgpu_ctx_get_fence(ctx, entity, user->seq_no);
        amdgpu_ctx_put(ctx);

        return fence;
}

int amdgpu_cs_fence_to_handle_ioctl(struct drm_device *dev, void *data,
                                    struct drm_file *filp)
{
        struct amdgpu_device *adev = drm_to_adev(dev);
        union drm_amdgpu_fence_to_handle *info = data;
        struct dma_fence *fence;
        struct drm_syncobj *syncobj;
        struct sync_file *sync_file;
        int fd, r;

        fence = amdgpu_cs_get_fence(adev, filp, &info->in.fence);
        if (IS_ERR(fence))
                return PTR_ERR(fence);

        if (!fence)
                fence = dma_fence_get_stub();

        switch (info->in.what) {
        case AMDGPU_FENCE_TO_HANDLE_GET_SYNCOBJ:
                r = drm_syncobj_create(&syncobj, 0, fence);
                dma_fence_put(fence);
                if (r)
                        return r;
                r = drm_syncobj_get_handle(filp, syncobj, &info->out.handle);
                drm_syncobj_put(syncobj);
                return r;

        case AMDGPU_FENCE_TO_HANDLE_GET_SYNCOBJ_FD:
                r = drm_syncobj_create(&syncobj, 0, fence);
                dma_fence_put(fence);
                if (r)
                        return r;
                r = drm_syncobj_get_fd(syncobj, (int *)&info->out.handle);
                drm_syncobj_put(syncobj);
                return r;

        case AMDGPU_FENCE_TO_HANDLE_GET_SYNC_FILE_FD:
                fd = get_unused_fd_flags(O_CLOEXEC);
                if (fd < 0) {
                        dma_fence_put(fence);
                        return fd;
                }

                sync_file = sync_file_create(fence);
                dma_fence_put(fence);
                if (!sync_file) {
                        put_unused_fd(fd);
                        return -ENOMEM;
                }

                fd_install(fd, sync_file->file);
                info->out.handle = fd;
                return 0;

        default:
                dma_fence_put(fence);
                return -EINVAL;
        }
}

/**
 * amdgpu_cs_wait_all_fences - wait on all fences to signal
 *
 * @adev: amdgpu device
 * @filp: file private
 * @wait: wait parameters
 * @fences: array of drm_amdgpu_fence
 */
static int amdgpu_cs_wait_all_fences(struct amdgpu_device *adev,
                                     struct drm_file *filp,
                                     union drm_amdgpu_wait_fences *wait,
                                     struct drm_amdgpu_fence *fences)
{
        uint32_t fence_count = wait->in.fence_count;
        unsigned int i;
        long r = 1;

        for (i = 0; i < fence_count; i++) {
                struct dma_fence *fence;
                unsigned long timeout = amdgpu_gem_timeout(wait->in.timeout_ns);

                fence = amdgpu_cs_get_fence(adev, filp, &fences[i]);
                if (IS_ERR(fence))
                        return PTR_ERR(fence);
                else if (!fence)
                        continue;

                r = dma_fence_wait_timeout(fence, true, timeout);
                dma_fence_put(fence);
                if (r < 0)
                        return r;

                if (r == 0)
                        break;

                if (fence->error)
                        return fence->error;
        }

        memset(wait, 0, sizeof(*wait));
        wait->out.status = (r > 0);

        return 0;
}

/**
 * amdgpu_cs_wait_any_fence - wait on any fence to signal
 *
 * @adev: amdgpu device
 * @filp: file private
 * @wait: wait parameters
 * @fences: array of drm_amdgpu_fence
 */
static int amdgpu_cs_wait_any_fence(struct amdgpu_device *adev,
                                    struct drm_file *filp,
                                    union drm_amdgpu_wait_fences *wait,
                                    struct drm_amdgpu_fence *fences)
{
        unsigned long timeout = amdgpu_gem_timeout(wait->in.timeout_ns);
        uint32_t fence_count = wait->in.fence_count;
        uint32_t first = ~0;
        struct dma_fence **array;
        unsigned int i;
        long r;

        /* Prepare the fence array */
        array = kcalloc(fence_count, sizeof(struct dma_fence *), GFP_KERNEL);

        if (array == NULL)
                return -ENOMEM;

        for (i = 0; i < fence_count; i++) {
                struct dma_fence *fence;

                fence = amdgpu_cs_get_fence(adev, filp, &fences[i]);
                if (IS_ERR(fence)) {
                        r = PTR_ERR(fence);
                        goto err_free_fence_array;
                } else if (fence) {
                        array[i] = fence;
                } else { /* NULL, the fence has been already signaled */
                        r = 1;
                        first = i;
                        goto out;
                }
        }

        r = dma_fence_wait_any_timeout(array, fence_count, true, timeout,
                                       &first);
        if (r < 0)
                goto err_free_fence_array;

out:
        memset(wait, 0, sizeof(*wait));
        wait->out.status = (r > 0);
        wait->out.first_signaled = first;

        if (first < fence_count && array[first])
                r = array[first]->error;
        else
                r = 0;

err_free_fence_array:
        for (i = 0; i < fence_count; i++)
                dma_fence_put(array[i]);
        kfree(array);

        return r;
}

/**
 * amdgpu_cs_wait_fences_ioctl - wait for multiple command submissions to finish
 *
 * @dev: drm device
 * @data: data from userspace
 * @filp: file private
 */
int amdgpu_cs_wait_fences_ioctl(struct drm_device *dev, void *data,
                                struct drm_file *filp)
{
        struct amdgpu_device *adev = drm_to_adev(dev);
        union drm_amdgpu_wait_fences *wait = data;
        uint32_t fence_count = wait->in.fence_count;
        struct drm_amdgpu_fence *fences_user;
        struct drm_amdgpu_fence *fences;
        int r;

        /* Get the fences from userspace */
        fences = kmalloc_array(fence_count, sizeof(struct drm_amdgpu_fence),
                        GFP_KERNEL);
        if (fences == NULL)
                return -ENOMEM;

        fences_user = u64_to_user_ptr(wait->in.fences);
        if (copy_from_user(fences, fences_user,
                sizeof(struct drm_amdgpu_fence) * fence_count)) {
                r = -EFAULT;
                goto err_free_fences;
        }

        if (wait->in.wait_all)
                r = amdgpu_cs_wait_all_fences(adev, filp, wait, fences);
        else
                r = amdgpu_cs_wait_any_fence(adev, filp, wait, fences);

err_free_fences:
        kfree(fences);

        return r;
}

/**
 * amdgpu_cs_find_mapping - find bo_va for VM address
 *
 * @parser: command submission parser context
 * @addr: VM address
 * @bo: resulting BO of the mapping found
 * @map: Placeholder to return found BO mapping
 *
 * Search the buffer objects in the command submission context for a certain
 * virtual memory address. Returns allocation structure when found, NULL
 * otherwise.
 */
int amdgpu_cs_find_mapping(struct amdgpu_cs_parser *parser,
                           uint64_t addr, struct amdgpu_bo **bo,
                           struct amdgpu_bo_va_mapping **map)
{
        struct amdgpu_fpriv *fpriv = parser->filp->driver_priv;
        struct ttm_operation_ctx ctx = { false, false };
        struct amdgpu_vm *vm = &fpriv->vm;
        struct amdgpu_bo_va_mapping *mapping;
        int r;

        addr /= AMDGPU_GPU_PAGE_SIZE;

        mapping = amdgpu_vm_bo_lookup_mapping(vm, addr);
        if (!mapping || !mapping->bo_va || !mapping->bo_va->base.bo)
                return -EINVAL;

        *bo = mapping->bo_va->base.bo;
        *map = mapping;

        /* Double check that the BO is reserved by this CS */
        if (dma_resv_locking_ctx((*bo)->tbo.base.resv) != &parser->ticket)
                return -EINVAL;

        if (!((*bo)->flags & AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS)) {
                (*bo)->flags |= AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS;
                amdgpu_bo_placement_from_domain(*bo, (*bo)->allowed_domains);
                r = ttm_bo_validate(&(*bo)->tbo, &(*bo)->placement, &ctx);
                if (r)
                        return r;
        }

        return amdgpu_ttm_alloc_gart(&(*bo)->tbo);
}