Linux 5.16-rc5

[J-linux.git] / drivers / gpu / drm / amd / amdgpu / amdgpu_amdkfd_gpuvm.c

/*
 * Copyright 2014-2018 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */
#include <linux/dma-buf.h>
#include <linux/list.h>
#include <linux/pagemap.h>
#include <linux/sched/mm.h>
#include <linux/sched/task.h>

#include "amdgpu_object.h"
#include "amdgpu_gem.h"
#include "amdgpu_vm.h"
#include "amdgpu_amdkfd.h"
#include "amdgpu_dma_buf.h"
#include <uapi/linux/kfd_ioctl.h>
#include "amdgpu_xgmi.h"

/* Userptr restore delay, just long enough to allow consecutive VM
 * changes to accumulate
 */
#define AMDGPU_USERPTR_RESTORE_DELAY_MS 1

/* Impose limit on how much memory KFD can use */
static struct {
        uint64_t max_system_mem_limit;
        uint64_t max_ttm_mem_limit;
        int64_t system_mem_used;
        int64_t ttm_mem_used;
        spinlock_t mem_limit_lock;
} kfd_mem_limit;

static const char * const domain_bit_to_string[] = {
                "CPU",
                "GTT",
                "VRAM",
                "GDS",
                "GWS",
                "OA"
};

#define domain_string(domain) domain_bit_to_string[ffs(domain)-1]

static void amdgpu_amdkfd_restore_userptr_worker(struct work_struct *work);


static inline struct amdgpu_device *get_amdgpu_device(struct kgd_dev *kgd)
{
        return (struct amdgpu_device *)kgd;
}

static bool kfd_mem_is_attached(struct amdgpu_vm *avm,
                struct kgd_mem *mem)
{
        struct kfd_mem_attachment *entry;

        list_for_each_entry(entry, &mem->attachments, list)
                if (entry->bo_va->base.vm == avm)
                        return true;

        return false;
}

/* Set memory usage limits. Current, limits are
 *  System (TTM + userptr) memory - 15/16th System RAM
 *  TTM memory - 3/8th System RAM
 */
void amdgpu_amdkfd_gpuvm_init_mem_limits(void)
{
        struct sysinfo si;
        uint64_t mem;

        si_meminfo(&si);
        mem = si.freeram - si.freehigh;
        mem *= si.mem_unit;

        spin_lock_init(&kfd_mem_limit.mem_limit_lock);
        kfd_mem_limit.max_system_mem_limit = mem - (mem >> 4);
        kfd_mem_limit.max_ttm_mem_limit = (mem >> 1) - (mem >> 3);
        pr_debug("Kernel memory limit %lluM, TTM limit %lluM\n",
                (kfd_mem_limit.max_system_mem_limit >> 20),
                (kfd_mem_limit.max_ttm_mem_limit >> 20));
}

void amdgpu_amdkfd_reserve_system_mem(uint64_t size)
{
        kfd_mem_limit.system_mem_used += size;
}

/* Estimate page table size needed to represent a given memory size
 *
 * With 4KB pages, we need one 8 byte PTE for each 4KB of memory
 * (factor 512, >> 9). With 2MB pages, we need one 8 byte PTE for 2MB
 * of memory (factor 256K, >> 18). ROCm user mode tries to optimize
 * for 2MB pages for TLB efficiency. However, small allocations and
 * fragmented system memory still need some 4KB pages. We choose a
 * compromise that should work in most cases without reserving too
 * much memory for page tables unnecessarily (factor 16K, >> 14).
 */
#define ESTIMATE_PT_SIZE(mem_size) ((mem_size) >> 14)

static size_t amdgpu_amdkfd_acc_size(uint64_t size)
{
        size >>= PAGE_SHIFT;
        size *= sizeof(dma_addr_t) + sizeof(void *);

        return __roundup_pow_of_two(sizeof(struct amdgpu_bo)) +
                __roundup_pow_of_two(sizeof(struct ttm_tt)) +
                PAGE_ALIGN(size);
}

static int amdgpu_amdkfd_reserve_mem_limit(struct amdgpu_device *adev,
                uint64_t size, u32 domain, bool sg)
{
        uint64_t reserved_for_pt =
                ESTIMATE_PT_SIZE(amdgpu_amdkfd_total_mem_size);
        size_t acc_size, system_mem_needed, ttm_mem_needed, vram_needed;
        int ret = 0;

        acc_size = amdgpu_amdkfd_acc_size(size);

        vram_needed = 0;
        if (domain == AMDGPU_GEM_DOMAIN_GTT) {
                /* TTM GTT memory */
                system_mem_needed = acc_size + size;
                ttm_mem_needed = acc_size + size;
        } else if (domain == AMDGPU_GEM_DOMAIN_CPU && !sg) {
                /* Userptr */
                system_mem_needed = acc_size + size;
                ttm_mem_needed = acc_size;
        } else {
                /* VRAM and SG */
                system_mem_needed = acc_size;
                ttm_mem_needed = acc_size;
                if (domain == AMDGPU_GEM_DOMAIN_VRAM)
                        vram_needed = size;
        }

        spin_lock(&kfd_mem_limit.mem_limit_lock);

        if (kfd_mem_limit.system_mem_used + system_mem_needed >
            kfd_mem_limit.max_system_mem_limit)
                pr_debug("Set no_system_mem_limit=1 if using shared memory\n");

        if ((kfd_mem_limit.system_mem_used + system_mem_needed >
             kfd_mem_limit.max_system_mem_limit && !no_system_mem_limit) ||
            (kfd_mem_limit.ttm_mem_used + ttm_mem_needed >
             kfd_mem_limit.max_ttm_mem_limit) ||
            (adev->kfd.vram_used + vram_needed >
             adev->gmc.real_vram_size - reserved_for_pt)) {
                ret = -ENOMEM;
        } else {
                kfd_mem_limit.system_mem_used += system_mem_needed;
                kfd_mem_limit.ttm_mem_used += ttm_mem_needed;
                adev->kfd.vram_used += vram_needed;
        }

        spin_unlock(&kfd_mem_limit.mem_limit_lock);
        return ret;
}

static void unreserve_mem_limit(struct amdgpu_device *adev,
                uint64_t size, u32 domain, bool sg)
{
        size_t acc_size;

        acc_size = amdgpu_amdkfd_acc_size(size);

        spin_lock(&kfd_mem_limit.mem_limit_lock);
        if (domain == AMDGPU_GEM_DOMAIN_GTT) {
                kfd_mem_limit.system_mem_used -= (acc_size + size);
                kfd_mem_limit.ttm_mem_used -= (acc_size + size);
        } else if (domain == AMDGPU_GEM_DOMAIN_CPU && !sg) {
                kfd_mem_limit.system_mem_used -= (acc_size + size);
                kfd_mem_limit.ttm_mem_used -= acc_size;
        } else {
                kfd_mem_limit.system_mem_used -= acc_size;
                kfd_mem_limit.ttm_mem_used -= acc_size;
                if (domain == AMDGPU_GEM_DOMAIN_VRAM) {
                        adev->kfd.vram_used -= size;
                        WARN_ONCE(adev->kfd.vram_used < 0,
                                  "kfd VRAM memory accounting unbalanced");
                }
        }
        WARN_ONCE(kfd_mem_limit.system_mem_used < 0,
                  "kfd system memory accounting unbalanced");
        WARN_ONCE(kfd_mem_limit.ttm_mem_used < 0,
                  "kfd TTM memory accounting unbalanced");

        spin_unlock(&kfd_mem_limit.mem_limit_lock);
}

void amdgpu_amdkfd_release_notify(struct amdgpu_bo *bo)
{
        struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
        u32 domain = bo->preferred_domains;
        bool sg = (bo->preferred_domains == AMDGPU_GEM_DOMAIN_CPU);

        if (bo->flags & AMDGPU_AMDKFD_CREATE_USERPTR_BO) {
                domain = AMDGPU_GEM_DOMAIN_CPU;
                sg = false;
        }

        unreserve_mem_limit(adev, amdgpu_bo_size(bo), domain, sg);

        kfree(bo->kfd_bo);
}


/* amdgpu_amdkfd_remove_eviction_fence - Removes eviction fence from BO's
 *  reservation object.
 *
 * @bo: [IN] Remove eviction fence(s) from this BO
 * @ef: [IN] This eviction fence is removed if it
 *  is present in the shared list.
 *
 * NOTE: Must be called with BO reserved i.e. bo->tbo.resv->lock held.
 */
static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo,
                                        struct amdgpu_amdkfd_fence *ef)
{
        struct dma_resv *resv = bo->tbo.base.resv;
        struct dma_resv_list *old, *new;
        unsigned int i, j, k;

        if (!ef)
                return -EINVAL;

        old = dma_resv_shared_list(resv);
        if (!old)
                return 0;

        new = kmalloc(struct_size(new, shared, old->shared_max), GFP_KERNEL);
        if (!new)
                return -ENOMEM;

        /* Go through all the shared fences in the resevation object and sort
         * the interesting ones to the end of the list.
         */
        for (i = 0, j = old->shared_count, k = 0; i < old->shared_count; ++i) {
                struct dma_fence *f;

                f = rcu_dereference_protected(old->shared[i],
                                              dma_resv_held(resv));

                if (f->context == ef->base.context)
                        RCU_INIT_POINTER(new->shared[--j], f);
                else
                        RCU_INIT_POINTER(new->shared[k++], f);
        }
        new->shared_max = old->shared_max;
        new->shared_count = k;

        /* Install the new fence list, seqcount provides the barriers */
        write_seqcount_begin(&resv->seq);
        RCU_INIT_POINTER(resv->fence, new);
        write_seqcount_end(&resv->seq);

        /* Drop the references to the removed fences or move them to ef_list */
        for (i = j; i < old->shared_count; ++i) {
                struct dma_fence *f;

                f = rcu_dereference_protected(new->shared[i],
                                              dma_resv_held(resv));
                dma_fence_put(f);
        }
        kfree_rcu(old, rcu);

        return 0;
}

int amdgpu_amdkfd_remove_fence_on_pt_pd_bos(struct amdgpu_bo *bo)
{
        struct amdgpu_bo *root = bo;
        struct amdgpu_vm_bo_base *vm_bo;
        struct amdgpu_vm *vm;
        struct amdkfd_process_info *info;
        struct amdgpu_amdkfd_fence *ef;
        int ret;

        /* we can always get vm_bo from root PD bo.*/
        while (root->parent)
                root = root->parent;

        vm_bo = root->vm_bo;
        if (!vm_bo)
                return 0;

        vm = vm_bo->vm;
        if (!vm)
                return 0;

        info = vm->process_info;
        if (!info || !info->eviction_fence)
                return 0;

        ef = container_of(dma_fence_get(&info->eviction_fence->base),
                        struct amdgpu_amdkfd_fence, base);

        BUG_ON(!dma_resv_trylock(bo->tbo.base.resv));
        ret = amdgpu_amdkfd_remove_eviction_fence(bo, ef);
        dma_resv_unlock(bo->tbo.base.resv);

        dma_fence_put(&ef->base);
        return ret;
}

static int amdgpu_amdkfd_bo_validate(struct amdgpu_bo *bo, uint32_t domain,
                                     bool wait)
{
        struct ttm_operation_ctx ctx = { false, false };
        int ret;

        if (WARN(amdgpu_ttm_tt_get_usermm(bo->tbo.ttm),
                 "Called with userptr BO"))
                return -EINVAL;

        amdgpu_bo_placement_from_domain(bo, domain);

        ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
        if (ret)
                goto validate_fail;
        if (wait)
                amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);

validate_fail:
        return ret;
}

static int amdgpu_amdkfd_validate_vm_bo(void *_unused, struct amdgpu_bo *bo)
{
        return amdgpu_amdkfd_bo_validate(bo, bo->allowed_domains, false);
}

/* vm_validate_pt_pd_bos - Validate page table and directory BOs
 *
 * Page directories are not updated here because huge page handling
 * during page table updates can invalidate page directory entries
 * again. Page directories are only updated after updating page
 * tables.
 */
static int vm_validate_pt_pd_bos(struct amdgpu_vm *vm)
{
        struct amdgpu_bo *pd = vm->root.bo;
        struct amdgpu_device *adev = amdgpu_ttm_adev(pd->tbo.bdev);
        int ret;

        ret = amdgpu_vm_validate_pt_bos(adev, vm, amdgpu_amdkfd_validate_vm_bo, NULL);
        if (ret) {
                pr_err("failed to validate PT BOs\n");
                return ret;
        }

        ret = amdgpu_amdkfd_validate_vm_bo(NULL, pd);
        if (ret) {
                pr_err("failed to validate PD\n");
                return ret;
        }

        vm->pd_phys_addr = amdgpu_gmc_pd_addr(vm->root.bo);

        if (vm->use_cpu_for_update) {
                ret = amdgpu_bo_kmap(pd, NULL);
                if (ret) {
                        pr_err("failed to kmap PD, ret=%d\n", ret);
                        return ret;
                }
        }

        return 0;
}

static int vm_update_pds(struct amdgpu_vm *vm, struct amdgpu_sync *sync)
{
        struct amdgpu_bo *pd = vm->root.bo;
        struct amdgpu_device *adev = amdgpu_ttm_adev(pd->tbo.bdev);
        int ret;

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

        return amdgpu_sync_fence(sync, vm->last_update);
}

static uint64_t get_pte_flags(struct amdgpu_device *adev, struct kgd_mem *mem)
{
        struct amdgpu_device *bo_adev = amdgpu_ttm_adev(mem->bo->tbo.bdev);
        bool coherent = mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_COHERENT;
        bool uncached = mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_UNCACHED;
        uint32_t mapping_flags;
        uint64_t pte_flags;
        bool snoop = false;

        mapping_flags = AMDGPU_VM_PAGE_READABLE;
        if (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE)
                mapping_flags |= AMDGPU_VM_PAGE_WRITEABLE;
        if (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_EXECUTABLE)
                mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;

        switch (adev->asic_type) {
        case CHIP_ARCTURUS:
                if (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_VRAM) {
                        if (bo_adev == adev)
                                mapping_flags |= coherent ?
                                        AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
                        else
                                mapping_flags |= coherent ?
                                        AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
                } else {
                        mapping_flags |= coherent ?
                                AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
                }
                break;
        case CHIP_ALDEBARAN:
                if (coherent && uncached) {
                        if (adev->gmc.xgmi.connected_to_cpu ||
                                !(mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_VRAM))
                                snoop = true;
                        mapping_flags |= AMDGPU_VM_MTYPE_UC;
                } else if (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_VRAM) {
                        if (bo_adev == adev) {
                                mapping_flags |= coherent ?
                                        AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
                                if (adev->gmc.xgmi.connected_to_cpu)
                                        snoop = true;
                        } else {
                                mapping_flags |= coherent ?
                                        AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
                                if (amdgpu_xgmi_same_hive(adev, bo_adev))
                                        snoop = true;
                        }
                } else {
                        snoop = true;
                        mapping_flags |= coherent ?
                                AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
                }
                break;
        default:
                mapping_flags |= coherent ?
                        AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
        }

        pte_flags = amdgpu_gem_va_map_flags(adev, mapping_flags);
        pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;

        return pte_flags;
}

static int
kfd_mem_dmamap_userptr(struct kgd_mem *mem,
                       struct kfd_mem_attachment *attachment)
{
        enum dma_data_direction direction =
                mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ?
                DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
        struct ttm_operation_ctx ctx = {.interruptible = true};
        struct amdgpu_bo *bo = attachment->bo_va->base.bo;
        struct amdgpu_device *adev = attachment->adev;
        struct ttm_tt *src_ttm = mem->bo->tbo.ttm;
        struct ttm_tt *ttm = bo->tbo.ttm;
        int ret;

        ttm->sg = kmalloc(sizeof(*ttm->sg), GFP_KERNEL);
        if (unlikely(!ttm->sg))
                return -ENOMEM;

        if (WARN_ON(ttm->num_pages != src_ttm->num_pages))
                return -EINVAL;

        /* Same sequence as in amdgpu_ttm_tt_pin_userptr */
        ret = sg_alloc_table_from_pages(ttm->sg, src_ttm->pages,
                                        ttm->num_pages, 0,
                                        (u64)ttm->num_pages << PAGE_SHIFT,
                                        GFP_KERNEL);
        if (unlikely(ret))
                goto free_sg;

        ret = dma_map_sgtable(adev->dev, ttm->sg, direction, 0);
        if (unlikely(ret))
                goto release_sg;

        drm_prime_sg_to_dma_addr_array(ttm->sg, ttm->dma_address,
                                       ttm->num_pages);

        amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT);
        ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
        if (ret)
                goto unmap_sg;

        return 0;

unmap_sg:
        dma_unmap_sgtable(adev->dev, ttm->sg, direction, 0);
release_sg:
        pr_err("DMA map userptr failed: %d\n", ret);
        sg_free_table(ttm->sg);
free_sg:
        kfree(ttm->sg);
        ttm->sg = NULL;
        return ret;
}

static int
kfd_mem_dmamap_dmabuf(struct kfd_mem_attachment *attachment)
{
        struct ttm_operation_ctx ctx = {.interruptible = true};
        struct amdgpu_bo *bo = attachment->bo_va->base.bo;

        amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT);
        return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
}

static int
kfd_mem_dmamap_attachment(struct kgd_mem *mem,
                          struct kfd_mem_attachment *attachment)
{
        switch (attachment->type) {
        case KFD_MEM_ATT_SHARED:
                return 0;
        case KFD_MEM_ATT_USERPTR:
                return kfd_mem_dmamap_userptr(mem, attachment);
        case KFD_MEM_ATT_DMABUF:
                return kfd_mem_dmamap_dmabuf(attachment);
        default:
                WARN_ON_ONCE(1);
        }
        return -EINVAL;
}

static void
kfd_mem_dmaunmap_userptr(struct kgd_mem *mem,
                         struct kfd_mem_attachment *attachment)
{
        enum dma_data_direction direction =
                mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ?
                DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
        struct ttm_operation_ctx ctx = {.interruptible = false};
        struct amdgpu_bo *bo = attachment->bo_va->base.bo;
        struct amdgpu_device *adev = attachment->adev;
        struct ttm_tt *ttm = bo->tbo.ttm;

        if (unlikely(!ttm->sg))
                return;

        amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
        ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);

        dma_unmap_sgtable(adev->dev, ttm->sg, direction, 0);
        sg_free_table(ttm->sg);
        kfree(ttm->sg);
        ttm->sg = NULL;
}

static void
kfd_mem_dmaunmap_dmabuf(struct kfd_mem_attachment *attachment)
{
        struct ttm_operation_ctx ctx = {.interruptible = true};
        struct amdgpu_bo *bo = attachment->bo_va->base.bo;

        amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
        ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
}

static void
kfd_mem_dmaunmap_attachment(struct kgd_mem *mem,
                            struct kfd_mem_attachment *attachment)
{
        switch (attachment->type) {
        case KFD_MEM_ATT_SHARED:
                break;
        case KFD_MEM_ATT_USERPTR:
                kfd_mem_dmaunmap_userptr(mem, attachment);
                break;
        case KFD_MEM_ATT_DMABUF:
                kfd_mem_dmaunmap_dmabuf(attachment);
                break;
        default:
                WARN_ON_ONCE(1);
        }
}

static int
kfd_mem_attach_userptr(struct amdgpu_device *adev, struct kgd_mem *mem,
                       struct amdgpu_bo **bo)
{
        unsigned long bo_size = mem->bo->tbo.base.size;
        struct drm_gem_object *gobj;
        int ret;

        ret = amdgpu_bo_reserve(mem->bo, false);
        if (ret)
                return ret;

        ret = amdgpu_gem_object_create(adev, bo_size, 1,
                                       AMDGPU_GEM_DOMAIN_CPU,
                                       AMDGPU_GEM_CREATE_PREEMPTIBLE,
                                       ttm_bo_type_sg, mem->bo->tbo.base.resv,
                                       &gobj);
        amdgpu_bo_unreserve(mem->bo);
        if (ret)
                return ret;

        *bo = gem_to_amdgpu_bo(gobj);
        (*bo)->parent = amdgpu_bo_ref(mem->bo);

        return 0;
}

static int
kfd_mem_attach_dmabuf(struct amdgpu_device *adev, struct kgd_mem *mem,
                      struct amdgpu_bo **bo)
{
        struct drm_gem_object *gobj;
        int ret;

        if (!mem->dmabuf) {
                mem->dmabuf = amdgpu_gem_prime_export(&mem->bo->tbo.base,
                        mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ?
                                DRM_RDWR : 0);
                if (IS_ERR(mem->dmabuf)) {
                        ret = PTR_ERR(mem->dmabuf);
                        mem->dmabuf = NULL;
                        return ret;
                }
        }

        gobj = amdgpu_gem_prime_import(adev_to_drm(adev), mem->dmabuf);
        if (IS_ERR(gobj))
                return PTR_ERR(gobj);

        *bo = gem_to_amdgpu_bo(gobj);
        (*bo)->flags |= AMDGPU_GEM_CREATE_PREEMPTIBLE;
        (*bo)->parent = amdgpu_bo_ref(mem->bo);

        return 0;
}

/* kfd_mem_attach - Add a BO to a VM
 *
 * Everything that needs to bo done only once when a BO is first added
 * to a VM. It can later be mapped and unmapped many times without
 * repeating these steps.
 *
 * 0. Create BO for DMA mapping, if needed
 * 1. Allocate and initialize BO VA entry data structure
 * 2. Add BO to the VM
 * 3. Determine ASIC-specific PTE flags
 * 4. Alloc page tables and directories if needed
 * 4a.  Validate new page tables and directories
 */
static int kfd_mem_attach(struct amdgpu_device *adev, struct kgd_mem *mem,
                struct amdgpu_vm *vm, bool is_aql)
{
        struct amdgpu_device *bo_adev = amdgpu_ttm_adev(mem->bo->tbo.bdev);
        unsigned long bo_size = mem->bo->tbo.base.size;
        uint64_t va = mem->va;
        struct kfd_mem_attachment *attachment[2] = {NULL, NULL};
        struct amdgpu_bo *bo[2] = {NULL, NULL};
        int i, ret;

        if (!va) {
                pr_err("Invalid VA when adding BO to VM\n");
                return -EINVAL;
        }

        for (i = 0; i <= is_aql; i++) {
                attachment[i] = kzalloc(sizeof(*attachment[i]), GFP_KERNEL);
                if (unlikely(!attachment[i])) {
                        ret = -ENOMEM;
                        goto unwind;
                }

                pr_debug("\t add VA 0x%llx - 0x%llx to vm %p\n", va,
                         va + bo_size, vm);

                if (adev == bo_adev || (mem->domain == AMDGPU_GEM_DOMAIN_VRAM &&
                                        amdgpu_xgmi_same_hive(adev, bo_adev))) {
                        /* Mappings on the local GPU and VRAM mappings in the
                         * local hive share the original BO
                         */
                        attachment[i]->type = KFD_MEM_ATT_SHARED;
                        bo[i] = mem->bo;
                        drm_gem_object_get(&bo[i]->tbo.base);
                } else if (i > 0) {
                        /* Multiple mappings on the same GPU share the BO */
                        attachment[i]->type = KFD_MEM_ATT_SHARED;
                        bo[i] = bo[0];
                        drm_gem_object_get(&bo[i]->tbo.base);
                } else if (amdgpu_ttm_tt_get_usermm(mem->bo->tbo.ttm)) {
                        /* Create an SG BO to DMA-map userptrs on other GPUs */
                        attachment[i]->type = KFD_MEM_ATT_USERPTR;
                        ret = kfd_mem_attach_userptr(adev, mem, &bo[i]);
                        if (ret)
                                goto unwind;
                } else if (mem->domain == AMDGPU_GEM_DOMAIN_GTT &&
                           mem->bo->tbo.type != ttm_bo_type_sg) {
                        /* GTT BOs use DMA-mapping ability of dynamic-attach
                         * DMA bufs. TODO: The same should work for VRAM on
                         * large-BAR GPUs.
                         */
                        attachment[i]->type = KFD_MEM_ATT_DMABUF;
                        ret = kfd_mem_attach_dmabuf(adev, mem, &bo[i]);
                        if (ret)
                                goto unwind;
                } else {
                        /* FIXME: Need to DMA-map other BO types:
                         * large-BAR VRAM, doorbells, MMIO remap
                         */
                        attachment[i]->type = KFD_MEM_ATT_SHARED;
                        bo[i] = mem->bo;
                        drm_gem_object_get(&bo[i]->tbo.base);
                }

                /* Add BO to VM internal data structures */
                ret = amdgpu_bo_reserve(bo[i], false);
                if (ret) {
                        pr_debug("Unable to reserve BO during memory attach");
                        goto unwind;
                }
                attachment[i]->bo_va = amdgpu_vm_bo_add(adev, vm, bo[i]);
                amdgpu_bo_unreserve(bo[i]);
                if (unlikely(!attachment[i]->bo_va)) {
                        ret = -ENOMEM;
                        pr_err("Failed to add BO object to VM. ret == %d\n",
                               ret);
                        goto unwind;
                }
                attachment[i]->va = va;
                attachment[i]->pte_flags = get_pte_flags(adev, mem);
                attachment[i]->adev = adev;
                list_add(&attachment[i]->list, &mem->attachments);

                va += bo_size;
        }

        return 0;

unwind:
        for (; i >= 0; i--) {
                if (!attachment[i])
                        continue;
                if (attachment[i]->bo_va) {
                        amdgpu_bo_reserve(bo[i], true);
                        amdgpu_vm_bo_rmv(adev, attachment[i]->bo_va);
                        amdgpu_bo_unreserve(bo[i]);
                        list_del(&attachment[i]->list);
                }
                if (bo[i])
                        drm_gem_object_put(&bo[i]->tbo.base);
                kfree(attachment[i]);
        }
        return ret;
}

static void kfd_mem_detach(struct kfd_mem_attachment *attachment)
{
        struct amdgpu_bo *bo = attachment->bo_va->base.bo;

        pr_debug("\t remove VA 0x%llx in entry %p\n",
                        attachment->va, attachment);
        amdgpu_vm_bo_rmv(attachment->adev, attachment->bo_va);
        drm_gem_object_put(&bo->tbo.base);
        list_del(&attachment->list);
        kfree(attachment);
}

static void add_kgd_mem_to_kfd_bo_list(struct kgd_mem *mem,
                                struct amdkfd_process_info *process_info,
                                bool userptr)
{
        struct ttm_validate_buffer *entry = &mem->validate_list;
        struct amdgpu_bo *bo = mem->bo;

        INIT_LIST_HEAD(&entry->head);
        entry->num_shared = 1;
        entry->bo = &bo->tbo;
        mutex_lock(&process_info->lock);
        if (userptr)
                list_add_tail(&entry->head, &process_info->userptr_valid_list);
        else
                list_add_tail(&entry->head, &process_info->kfd_bo_list);
        mutex_unlock(&process_info->lock);
}

static void remove_kgd_mem_from_kfd_bo_list(struct kgd_mem *mem,
                struct amdkfd_process_info *process_info)
{
        struct ttm_validate_buffer *bo_list_entry;

        bo_list_entry = &mem->validate_list;
        mutex_lock(&process_info->lock);
        list_del(&bo_list_entry->head);
        mutex_unlock(&process_info->lock);
}

/* Initializes user pages. It registers the MMU notifier and validates
 * the userptr BO in the GTT domain.
 *
 * The BO must already be on the userptr_valid_list. Otherwise an
 * eviction and restore may happen that leaves the new BO unmapped
 * with the user mode queues running.
 *
 * Takes the process_info->lock to protect against concurrent restore
 * workers.
 *
 * Returns 0 for success, negative errno for errors.
 */
static int init_user_pages(struct kgd_mem *mem, uint64_t user_addr)
{
        struct amdkfd_process_info *process_info = mem->process_info;
        struct amdgpu_bo *bo = mem->bo;
        struct ttm_operation_ctx ctx = { true, false };
        int ret = 0;

        mutex_lock(&process_info->lock);

        ret = amdgpu_ttm_tt_set_userptr(&bo->tbo, user_addr, 0);
        if (ret) {
                pr_err("%s: Failed to set userptr: %d\n", __func__, ret);
                goto out;
        }

        ret = amdgpu_mn_register(bo, user_addr);
        if (ret) {
                pr_err("%s: Failed to register MMU notifier: %d\n",
                       __func__, ret);
                goto out;
        }

        ret = amdgpu_ttm_tt_get_user_pages(bo, bo->tbo.ttm->pages);
        if (ret) {
                pr_err("%s: Failed to get user pages: %d\n", __func__, ret);
                goto unregister_out;
        }

        ret = amdgpu_bo_reserve(bo, true);
        if (ret) {
                pr_err("%s: Failed to reserve BO\n", __func__);
                goto release_out;
        }
        amdgpu_bo_placement_from_domain(bo, mem->domain);
        ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
        if (ret)
                pr_err("%s: failed to validate BO\n", __func__);
        amdgpu_bo_unreserve(bo);

release_out:
        amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
unregister_out:
        if (ret)
                amdgpu_mn_unregister(bo);
out:
        mutex_unlock(&process_info->lock);
        return ret;
}

/* Reserving a BO and its page table BOs must happen atomically to
 * avoid deadlocks. Some operations update multiple VMs at once. Track
 * all the reservation info in a context structure. Optionally a sync
 * object can track VM updates.
 */
struct bo_vm_reservation_context {
        struct amdgpu_bo_list_entry kfd_bo; /* BO list entry for the KFD BO */
        unsigned int n_vms;                 /* Number of VMs reserved       */
        struct amdgpu_bo_list_entry *vm_pd; /* Array of VM BO list entries  */
        struct ww_acquire_ctx ticket;       /* Reservation ticket           */
        struct list_head list, duplicates;  /* BO lists                     */
        struct amdgpu_sync *sync;           /* Pointer to sync object       */
        bool reserved;                      /* Whether BOs are reserved     */
};

enum bo_vm_match {
        BO_VM_NOT_MAPPED = 0,   /* Match VMs where a BO is not mapped */
        BO_VM_MAPPED,           /* Match VMs where a BO is mapped     */
        BO_VM_ALL,              /* Match all VMs a BO was added to    */
};

/**
 * reserve_bo_and_vm - reserve a BO and a VM unconditionally.
 * @mem: KFD BO structure.
 * @vm: the VM to reserve.
 * @ctx: the struct that will be used in unreserve_bo_and_vms().
 */
static int reserve_bo_and_vm(struct kgd_mem *mem,
                              struct amdgpu_vm *vm,
                              struct bo_vm_reservation_context *ctx)
{
        struct amdgpu_bo *bo = mem->bo;
        int ret;

        WARN_ON(!vm);

        ctx->reserved = false;
        ctx->n_vms = 1;
        ctx->sync = &mem->sync;

        INIT_LIST_HEAD(&ctx->list);
        INIT_LIST_HEAD(&ctx->duplicates);

        ctx->vm_pd = kcalloc(ctx->n_vms, sizeof(*ctx->vm_pd), GFP_KERNEL);
        if (!ctx->vm_pd)
                return -ENOMEM;

        ctx->kfd_bo.priority = 0;
        ctx->kfd_bo.tv.bo = &bo->tbo;
        ctx->kfd_bo.tv.num_shared = 1;
        list_add(&ctx->kfd_bo.tv.head, &ctx->list);

        amdgpu_vm_get_pd_bo(vm, &ctx->list, &ctx->vm_pd[0]);

        ret = ttm_eu_reserve_buffers(&ctx->ticket, &ctx->list,
                                     false, &ctx->duplicates);
        if (ret) {
                pr_err("Failed to reserve buffers in ttm.\n");
                kfree(ctx->vm_pd);
                ctx->vm_pd = NULL;
                return ret;
        }

        ctx->reserved = true;
        return 0;
}

/**
 * reserve_bo_and_cond_vms - reserve a BO and some VMs conditionally
 * @mem: KFD BO structure.
 * @vm: the VM to reserve. If NULL, then all VMs associated with the BO
 * is used. Otherwise, a single VM associated with the BO.
 * @map_type: the mapping status that will be used to filter the VMs.
 * @ctx: the struct that will be used in unreserve_bo_and_vms().
 *
 * Returns 0 for success, negative for failure.
 */
static int reserve_bo_and_cond_vms(struct kgd_mem *mem,
                                struct amdgpu_vm *vm, enum bo_vm_match map_type,
                                struct bo_vm_reservation_context *ctx)
{
        struct amdgpu_bo *bo = mem->bo;
        struct kfd_mem_attachment *entry;
        unsigned int i;
        int ret;

        ctx->reserved = false;
        ctx->n_vms = 0;
        ctx->vm_pd = NULL;
        ctx->sync = &mem->sync;

        INIT_LIST_HEAD(&ctx->list);
        INIT_LIST_HEAD(&ctx->duplicates);

        list_for_each_entry(entry, &mem->attachments, list) {
                if ((vm && vm != entry->bo_va->base.vm) ||
                        (entry->is_mapped != map_type
                        && map_type != BO_VM_ALL))
                        continue;

                ctx->n_vms++;
        }

        if (ctx->n_vms != 0) {
                ctx->vm_pd = kcalloc(ctx->n_vms, sizeof(*ctx->vm_pd),
                                     GFP_KERNEL);
                if (!ctx->vm_pd)
                        return -ENOMEM;
        }

        ctx->kfd_bo.priority = 0;
        ctx->kfd_bo.tv.bo = &bo->tbo;
        ctx->kfd_bo.tv.num_shared = 1;
        list_add(&ctx->kfd_bo.tv.head, &ctx->list);

        i = 0;
        list_for_each_entry(entry, &mem->attachments, list) {
                if ((vm && vm != entry->bo_va->base.vm) ||
                        (entry->is_mapped != map_type
                        && map_type != BO_VM_ALL))
                        continue;

                amdgpu_vm_get_pd_bo(entry->bo_va->base.vm, &ctx->list,
                                &ctx->vm_pd[i]);
                i++;
        }

        ret = ttm_eu_reserve_buffers(&ctx->ticket, &ctx->list,
                                     false, &ctx->duplicates);
        if (ret) {
                pr_err("Failed to reserve buffers in ttm.\n");
                kfree(ctx->vm_pd);
                ctx->vm_pd = NULL;
                return ret;
        }

        ctx->reserved = true;
        return 0;
}

/**
 * unreserve_bo_and_vms - Unreserve BO and VMs from a reservation context
 * @ctx: Reservation context to unreserve
 * @wait: Optionally wait for a sync object representing pending VM updates
 * @intr: Whether the wait is interruptible
 *
 * Also frees any resources allocated in
 * reserve_bo_and_(cond_)vm(s). Returns the status from
 * amdgpu_sync_wait.
 */
static int unreserve_bo_and_vms(struct bo_vm_reservation_context *ctx,
                                 bool wait, bool intr)
{
        int ret = 0;

        if (wait)
                ret = amdgpu_sync_wait(ctx->sync, intr);

        if (ctx->reserved)
                ttm_eu_backoff_reservation(&ctx->ticket, &ctx->list);
        kfree(ctx->vm_pd);

        ctx->sync = NULL;

        ctx->reserved = false;
        ctx->vm_pd = NULL;

        return ret;
}

static void unmap_bo_from_gpuvm(struct kgd_mem *mem,
                                struct kfd_mem_attachment *entry,
                                struct amdgpu_sync *sync)
{
        struct amdgpu_bo_va *bo_va = entry->bo_va;
        struct amdgpu_device *adev = entry->adev;
        struct amdgpu_vm *vm = bo_va->base.vm;

        amdgpu_vm_bo_unmap(adev, bo_va, entry->va);

        amdgpu_vm_clear_freed(adev, vm, &bo_va->last_pt_update);

        amdgpu_sync_fence(sync, bo_va->last_pt_update);

        kfd_mem_dmaunmap_attachment(mem, entry);
}

static int update_gpuvm_pte(struct kgd_mem *mem,
                            struct kfd_mem_attachment *entry,
                            struct amdgpu_sync *sync,
                            bool *table_freed)
{
        struct amdgpu_bo_va *bo_va = entry->bo_va;
        struct amdgpu_device *adev = entry->adev;
        int ret;

        ret = kfd_mem_dmamap_attachment(mem, entry);
        if (ret)
                return ret;

        /* Update the page tables  */
        ret = amdgpu_vm_bo_update(adev, bo_va, false, table_freed);
        if (ret) {
                pr_err("amdgpu_vm_bo_update failed\n");
                return ret;
        }

        return amdgpu_sync_fence(sync, bo_va->last_pt_update);
}

static int map_bo_to_gpuvm(struct kgd_mem *mem,
                           struct kfd_mem_attachment *entry,
                           struct amdgpu_sync *sync,
                           bool no_update_pte,
                           bool *table_freed)
{
        int ret;

        /* Set virtual address for the allocation */
        ret = amdgpu_vm_bo_map(entry->adev, entry->bo_va, entry->va, 0,
                               amdgpu_bo_size(entry->bo_va->base.bo),
                               entry->pte_flags);
        if (ret) {
                pr_err("Failed to map VA 0x%llx in vm. ret %d\n",
                                entry->va, ret);
                return ret;
        }

        if (no_update_pte)
                return 0;

        ret = update_gpuvm_pte(mem, entry, sync, table_freed);
        if (ret) {
                pr_err("update_gpuvm_pte() failed\n");
                goto update_gpuvm_pte_failed;
        }

        return 0;

update_gpuvm_pte_failed:
        unmap_bo_from_gpuvm(mem, entry, sync);
        return ret;
}

static struct sg_table *create_doorbell_sg(uint64_t addr, uint32_t size)
{
        struct sg_table *sg = kmalloc(sizeof(*sg), GFP_KERNEL);

        if (!sg)
                return NULL;
        if (sg_alloc_table(sg, 1, GFP_KERNEL)) {
                kfree(sg);
                return NULL;
        }
        sg->sgl->dma_address = addr;
        sg->sgl->length = size;
#ifdef CONFIG_NEED_SG_DMA_LENGTH
        sg->sgl->dma_length = size;
#endif
        return sg;
}

static int process_validate_vms(struct amdkfd_process_info *process_info)
{
        struct amdgpu_vm *peer_vm;
        int ret;

        list_for_each_entry(peer_vm, &process_info->vm_list_head,
                            vm_list_node) {
                ret = vm_validate_pt_pd_bos(peer_vm);
                if (ret)
                        return ret;
        }

        return 0;
}

static int process_sync_pds_resv(struct amdkfd_process_info *process_info,
                                 struct amdgpu_sync *sync)
{
        struct amdgpu_vm *peer_vm;
        int ret;

        list_for_each_entry(peer_vm, &process_info->vm_list_head,
                            vm_list_node) {
                struct amdgpu_bo *pd = peer_vm->root.bo;

                ret = amdgpu_sync_resv(NULL, sync, pd->tbo.base.resv,
                                       AMDGPU_SYNC_NE_OWNER,
                                       AMDGPU_FENCE_OWNER_KFD);
                if (ret)
                        return ret;
        }

        return 0;
}

static int process_update_pds(struct amdkfd_process_info *process_info,
                              struct amdgpu_sync *sync)
{
        struct amdgpu_vm *peer_vm;
        int ret;

        list_for_each_entry(peer_vm, &process_info->vm_list_head,
                            vm_list_node) {
                ret = vm_update_pds(peer_vm, sync);
                if (ret)
                        return ret;
        }

        return 0;
}

static int init_kfd_vm(struct amdgpu_vm *vm, void **process_info,
                       struct dma_fence **ef)
{
        struct amdkfd_process_info *info = NULL;
        int ret;

        if (!*process_info) {
                info = kzalloc(sizeof(*info), GFP_KERNEL);
                if (!info)
                        return -ENOMEM;

                mutex_init(&info->lock);
                INIT_LIST_HEAD(&info->vm_list_head);
                INIT_LIST_HEAD(&info->kfd_bo_list);
                INIT_LIST_HEAD(&info->userptr_valid_list);
                INIT_LIST_HEAD(&info->userptr_inval_list);

                info->eviction_fence =
                        amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
                                                   current->mm,
                                                   NULL);
                if (!info->eviction_fence) {
                        pr_err("Failed to create eviction fence\n");
                        ret = -ENOMEM;
                        goto create_evict_fence_fail;
                }

                info->pid = get_task_pid(current->group_leader, PIDTYPE_PID);
                atomic_set(&info->evicted_bos, 0);
                INIT_DELAYED_WORK(&info->restore_userptr_work,
                                  amdgpu_amdkfd_restore_userptr_worker);

                *process_info = info;
                *ef = dma_fence_get(&info->eviction_fence->base);
        }

        vm->process_info = *process_info;

        /* Validate page directory and attach eviction fence */
        ret = amdgpu_bo_reserve(vm->root.bo, true);
        if (ret)
                goto reserve_pd_fail;
        ret = vm_validate_pt_pd_bos(vm);
        if (ret) {
                pr_err("validate_pt_pd_bos() failed\n");
                goto validate_pd_fail;
        }
        ret = amdgpu_bo_sync_wait(vm->root.bo,
                                  AMDGPU_FENCE_OWNER_KFD, false);
        if (ret)
                goto wait_pd_fail;
        ret = dma_resv_reserve_shared(vm->root.bo->tbo.base.resv, 1);
        if (ret)
                goto reserve_shared_fail;
        amdgpu_bo_fence(vm->root.bo,
                        &vm->process_info->eviction_fence->base, true);
        amdgpu_bo_unreserve(vm->root.bo);

        /* Update process info */
        mutex_lock(&vm->process_info->lock);
        list_add_tail(&vm->vm_list_node,
                        &(vm->process_info->vm_list_head));
        vm->process_info->n_vms++;
        mutex_unlock(&vm->process_info->lock);

        return 0;

reserve_shared_fail:
wait_pd_fail:
validate_pd_fail:
        amdgpu_bo_unreserve(vm->root.bo);
reserve_pd_fail:
        vm->process_info = NULL;
        if (info) {
                /* Two fence references: one in info and one in *ef */
                dma_fence_put(&info->eviction_fence->base);
                dma_fence_put(*ef);
                *ef = NULL;
                *process_info = NULL;
                put_pid(info->pid);
create_evict_fence_fail:
                mutex_destroy(&info->lock);
                kfree(info);
        }
        return ret;
}

int amdgpu_amdkfd_gpuvm_acquire_process_vm(struct kgd_dev *kgd,
                                           struct file *filp, u32 pasid,
                                           void **process_info,
                                           struct dma_fence **ef)
{
        struct amdgpu_device *adev = get_amdgpu_device(kgd);
        struct amdgpu_fpriv *drv_priv;
        struct amdgpu_vm *avm;
        int ret;

        ret = amdgpu_file_to_fpriv(filp, &drv_priv);
        if (ret)
                return ret;
        avm = &drv_priv->vm;

        /* Already a compute VM? */
        if (avm->process_info)
                return -EINVAL;

        /* Free the original amdgpu allocated pasid,
         * will be replaced with kfd allocated pasid.
         */
        if (avm->pasid) {
                amdgpu_pasid_free(avm->pasid);
                amdgpu_vm_set_pasid(adev, avm, 0);
        }

        /* Convert VM into a compute VM */
        ret = amdgpu_vm_make_compute(adev, avm);
        if (ret)
                return ret;

        ret = amdgpu_vm_set_pasid(adev, avm, pasid);
        if (ret)
                return ret;
        /* Initialize KFD part of the VM and process info */
        ret = init_kfd_vm(avm, process_info, ef);
        if (ret)
                return ret;

        amdgpu_vm_set_task_info(avm);

        return 0;
}

void amdgpu_amdkfd_gpuvm_destroy_cb(struct amdgpu_device *adev,
                                    struct amdgpu_vm *vm)
{
        struct amdkfd_process_info *process_info = vm->process_info;
        struct amdgpu_bo *pd = vm->root.bo;

        if (!process_info)
                return;

        /* Release eviction fence from PD */
        amdgpu_bo_reserve(pd, false);
        amdgpu_bo_fence(pd, NULL, false);
        amdgpu_bo_unreserve(pd);

        /* Update process info */
        mutex_lock(&process_info->lock);
        process_info->n_vms--;
        list_del(&vm->vm_list_node);
        mutex_unlock(&process_info->lock);

        vm->process_info = NULL;

        /* Release per-process resources when last compute VM is destroyed */
        if (!process_info->n_vms) {
                WARN_ON(!list_empty(&process_info->kfd_bo_list));
                WARN_ON(!list_empty(&process_info->userptr_valid_list));
                WARN_ON(!list_empty(&process_info->userptr_inval_list));

                dma_fence_put(&process_info->eviction_fence->base);
                cancel_delayed_work_sync(&process_info->restore_userptr_work);
                put_pid(process_info->pid);
                mutex_destroy(&process_info->lock);
                kfree(process_info);
        }
}

void amdgpu_amdkfd_gpuvm_release_process_vm(struct kgd_dev *kgd, void *drm_priv)
{
        struct amdgpu_device *adev = get_amdgpu_device(kgd);
        struct amdgpu_vm *avm;

        if (WARN_ON(!kgd || !drm_priv))
                return;

        avm = drm_priv_to_vm(drm_priv);

        pr_debug("Releasing process vm %p\n", avm);

        /* The original pasid of amdgpu vm has already been
         * released during making a amdgpu vm to a compute vm
         * The current pasid is managed by kfd and will be
         * released on kfd process destroy. Set amdgpu pasid
         * to 0 to avoid duplicate release.
         */
        amdgpu_vm_release_compute(adev, avm);
}

uint64_t amdgpu_amdkfd_gpuvm_get_process_page_dir(void *drm_priv)
{
        struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
        struct amdgpu_bo *pd = avm->root.bo;
        struct amdgpu_device *adev = amdgpu_ttm_adev(pd->tbo.bdev);

        if (adev->asic_type < CHIP_VEGA10)
                return avm->pd_phys_addr >> AMDGPU_GPU_PAGE_SHIFT;
        return avm->pd_phys_addr;
}

int amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu(
                struct kgd_dev *kgd, uint64_t va, uint64_t size,
                void *drm_priv, struct kgd_mem **mem,
                uint64_t *offset, uint32_t flags)
{
        struct amdgpu_device *adev = get_amdgpu_device(kgd);
        struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
        enum ttm_bo_type bo_type = ttm_bo_type_device;
        struct sg_table *sg = NULL;
        uint64_t user_addr = 0;
        struct amdgpu_bo *bo;
        struct drm_gem_object *gobj = NULL;
        u32 domain, alloc_domain;
        u64 alloc_flags;
        int ret;

        /*
         * Check on which domain to allocate BO
         */
        if (flags & KFD_IOC_ALLOC_MEM_FLAGS_VRAM) {
                domain = alloc_domain = AMDGPU_GEM_DOMAIN_VRAM;
                alloc_flags = AMDGPU_GEM_CREATE_VRAM_WIPE_ON_RELEASE;
                alloc_flags |= (flags & KFD_IOC_ALLOC_MEM_FLAGS_PUBLIC) ?
                        AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED : 0;
        } else if (flags & KFD_IOC_ALLOC_MEM_FLAGS_GTT) {
                domain = alloc_domain = AMDGPU_GEM_DOMAIN_GTT;
                alloc_flags = 0;
        } else if (flags & KFD_IOC_ALLOC_MEM_FLAGS_USERPTR) {
                domain = AMDGPU_GEM_DOMAIN_GTT;
                alloc_domain = AMDGPU_GEM_DOMAIN_CPU;
                alloc_flags = AMDGPU_GEM_CREATE_PREEMPTIBLE;
                if (!offset || !*offset)
                        return -EINVAL;
                user_addr = untagged_addr(*offset);
        } else if (flags & (KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL |
                        KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP)) {
                domain = AMDGPU_GEM_DOMAIN_GTT;
                alloc_domain = AMDGPU_GEM_DOMAIN_CPU;
                bo_type = ttm_bo_type_sg;
                alloc_flags = 0;
                if (size > UINT_MAX)
                        return -EINVAL;
                sg = create_doorbell_sg(*offset, size);
                if (!sg)
                        return -ENOMEM;
        } else {
                return -EINVAL;
        }

        *mem = kzalloc(sizeof(struct kgd_mem), GFP_KERNEL);
        if (!*mem) {
                ret = -ENOMEM;
                goto err;
        }
        INIT_LIST_HEAD(&(*mem)->attachments);
        mutex_init(&(*mem)->lock);
        (*mem)->aql_queue = !!(flags & KFD_IOC_ALLOC_MEM_FLAGS_AQL_QUEUE_MEM);

        /* Workaround for AQL queue wraparound bug. Map the same
         * memory twice. That means we only actually allocate half
         * the memory.
         */
        if ((*mem)->aql_queue)
                size = size >> 1;

        (*mem)->alloc_flags = flags;

        amdgpu_sync_create(&(*mem)->sync);

        ret = amdgpu_amdkfd_reserve_mem_limit(adev, size, alloc_domain, !!sg);
        if (ret) {
                pr_debug("Insufficient memory\n");
                goto err_reserve_limit;
        }

        pr_debug("\tcreate BO VA 0x%llx size 0x%llx domain %s\n",
                        va, size, domain_string(alloc_domain));

        ret = amdgpu_gem_object_create(adev, size, 1, alloc_domain, alloc_flags,
                                       bo_type, NULL, &gobj);
        if (ret) {
                pr_debug("Failed to create BO on domain %s. ret %d\n",
                         domain_string(alloc_domain), ret);
                goto err_bo_create;
        }
        ret = drm_vma_node_allow(&gobj->vma_node, drm_priv);
        if (ret) {
                pr_debug("Failed to allow vma node access. ret %d\n", ret);
                goto err_node_allow;
        }
        bo = gem_to_amdgpu_bo(gobj);
        if (bo_type == ttm_bo_type_sg) {
                bo->tbo.sg = sg;
                bo->tbo.ttm->sg = sg;
        }
        bo->kfd_bo = *mem;
        (*mem)->bo = bo;
        if (user_addr)
                bo->flags |= AMDGPU_AMDKFD_CREATE_USERPTR_BO;

        (*mem)->va = va;
        (*mem)->domain = domain;
        (*mem)->mapped_to_gpu_memory = 0;
        (*mem)->process_info = avm->process_info;
        add_kgd_mem_to_kfd_bo_list(*mem, avm->process_info, user_addr);

        if (user_addr) {
                ret = init_user_pages(*mem, user_addr);
                if (ret)
                        goto allocate_init_user_pages_failed;
        }

        if (offset)
                *offset = amdgpu_bo_mmap_offset(bo);

        return 0;

allocate_init_user_pages_failed:
        remove_kgd_mem_from_kfd_bo_list(*mem, avm->process_info);
        drm_vma_node_revoke(&gobj->vma_node, drm_priv);
err_node_allow:
        /* Don't unreserve system mem limit twice */
        goto err_reserve_limit;
err_bo_create:
        unreserve_mem_limit(adev, size, alloc_domain, !!sg);
err_reserve_limit:
        mutex_destroy(&(*mem)->lock);
        if (gobj)
                drm_gem_object_put(gobj);
        else
                kfree(*mem);
err:
        if (sg) {
                sg_free_table(sg);
                kfree(sg);
        }
        return ret;
}

int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
                struct kgd_dev *kgd, struct kgd_mem *mem, void *drm_priv,
                uint64_t *size)
{
        struct amdkfd_process_info *process_info = mem->process_info;
        unsigned long bo_size = mem->bo->tbo.base.size;
        struct kfd_mem_attachment *entry, *tmp;
        struct bo_vm_reservation_context ctx;
        struct ttm_validate_buffer *bo_list_entry;
        unsigned int mapped_to_gpu_memory;
        int ret;
        bool is_imported = false;

        mutex_lock(&mem->lock);
        mapped_to_gpu_memory = mem->mapped_to_gpu_memory;
        is_imported = mem->is_imported;
        mutex_unlock(&mem->lock);
        /* lock is not needed after this, since mem is unused and will
         * be freed anyway
         */

        if (mapped_to_gpu_memory > 0) {
                pr_debug("BO VA 0x%llx size 0x%lx is still mapped.\n",
                                mem->va, bo_size);
                return -EBUSY;
        }

        /* Make sure restore workers don't access the BO any more */
        bo_list_entry = &mem->validate_list;
        mutex_lock(&process_info->lock);
        list_del(&bo_list_entry->head);
        mutex_unlock(&process_info->lock);

        /* No more MMU notifiers */
        amdgpu_mn_unregister(mem->bo);

        ret = reserve_bo_and_cond_vms(mem, NULL, BO_VM_ALL, &ctx);
        if (unlikely(ret))
                return ret;

        /* The eviction fence should be removed by the last unmap.
         * TODO: Log an error condition if the bo still has the eviction fence
         * attached
         */
        amdgpu_amdkfd_remove_eviction_fence(mem->bo,
                                        process_info->eviction_fence);
        pr_debug("Release VA 0x%llx - 0x%llx\n", mem->va,
                mem->va + bo_size * (1 + mem->aql_queue));

        /* Remove from VM internal data structures */
        list_for_each_entry_safe(entry, tmp, &mem->attachments, list)
                kfd_mem_detach(entry);

        ret = unreserve_bo_and_vms(&ctx, false, false);

        /* Free the sync object */
        amdgpu_sync_free(&mem->sync);

        /* If the SG is not NULL, it's one we created for a doorbell or mmio
         * remap BO. We need to free it.
         */
        if (mem->bo->tbo.sg) {
                sg_free_table(mem->bo->tbo.sg);
                kfree(mem->bo->tbo.sg);
        }

        /* Update the size of the BO being freed if it was allocated from
         * VRAM and is not imported.
         */
        if (size) {
                if ((mem->bo->preferred_domains == AMDGPU_GEM_DOMAIN_VRAM) &&
                    (!is_imported))
                        *size = bo_size;
                else
                        *size = 0;
        }

        /* Free the BO*/
        drm_vma_node_revoke(&mem->bo->tbo.base.vma_node, drm_priv);
        if (mem->dmabuf)
                dma_buf_put(mem->dmabuf);
        mutex_destroy(&mem->lock);

        /* If this releases the last reference, it will end up calling
         * amdgpu_amdkfd_release_notify and kfree the mem struct. That's why
         * this needs to be the last call here.
         */
        drm_gem_object_put(&mem->bo->tbo.base);

        return ret;
}

int amdgpu_amdkfd_gpuvm_map_memory_to_gpu(
                struct kgd_dev *kgd, struct kgd_mem *mem,
                void *drm_priv, bool *table_freed)
{
        struct amdgpu_device *adev = get_amdgpu_device(kgd);
        struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
        int ret;
        struct amdgpu_bo *bo;
        uint32_t domain;
        struct kfd_mem_attachment *entry;
        struct bo_vm_reservation_context ctx;
        unsigned long bo_size;
        bool is_invalid_userptr = false;

        bo = mem->bo;
        if (!bo) {
                pr_err("Invalid BO when mapping memory to GPU\n");
                return -EINVAL;
        }

        /* Make sure restore is not running concurrently. Since we
         * don't map invalid userptr BOs, we rely on the next restore
         * worker to do the mapping
         */
        mutex_lock(&mem->process_info->lock);

        /* Lock mmap-sem. If we find an invalid userptr BO, we can be
         * sure that the MMU notifier is no longer running
         * concurrently and the queues are actually stopped
         */
        if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) {
                mmap_write_lock(current->mm);
                is_invalid_userptr = atomic_read(&mem->invalid);
                mmap_write_unlock(current->mm);
        }

        mutex_lock(&mem->lock);

        domain = mem->domain;
        bo_size = bo->tbo.base.size;

        pr_debug("Map VA 0x%llx - 0x%llx to vm %p domain %s\n",
                        mem->va,
                        mem->va + bo_size * (1 + mem->aql_queue),
                        avm, domain_string(domain));

        if (!kfd_mem_is_attached(avm, mem)) {
                ret = kfd_mem_attach(adev, mem, avm, mem->aql_queue);
                if (ret)
                        goto out;
        }

        ret = reserve_bo_and_vm(mem, avm, &ctx);
        if (unlikely(ret))
                goto out;

        /* Userptr can be marked as "not invalid", but not actually be
         * validated yet (still in the system domain). In that case
         * the queues are still stopped and we can leave mapping for
         * the next restore worker
         */
        if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm) &&
            bo->tbo.resource->mem_type == TTM_PL_SYSTEM)
                is_invalid_userptr = true;

        ret = vm_validate_pt_pd_bos(avm);
        if (unlikely(ret))
                goto out_unreserve;

        if (mem->mapped_to_gpu_memory == 0 &&
            !amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) {
                /* Validate BO only once. The eviction fence gets added to BO
                 * the first time it is mapped. Validate will wait for all
                 * background evictions to complete.
                 */
                ret = amdgpu_amdkfd_bo_validate(bo, domain, true);
                if (ret) {
                        pr_debug("Validate failed\n");
                        goto out_unreserve;
                }
        }

        list_for_each_entry(entry, &mem->attachments, list) {
                if (entry->bo_va->base.vm != avm || entry->is_mapped)
                        continue;

                pr_debug("\t map VA 0x%llx - 0x%llx in entry %p\n",
                         entry->va, entry->va + bo_size, entry);

                ret = map_bo_to_gpuvm(mem, entry, ctx.sync,
                                      is_invalid_userptr, table_freed);
                if (ret) {
                        pr_err("Failed to map bo to gpuvm\n");
                        goto out_unreserve;
                }

                ret = vm_update_pds(avm, ctx.sync);
                if (ret) {
                        pr_err("Failed to update page directories\n");
                        goto out_unreserve;
                }

                entry->is_mapped = true;
                mem->mapped_to_gpu_memory++;
                pr_debug("\t INC mapping count %d\n",
                         mem->mapped_to_gpu_memory);
        }

        if (!amdgpu_ttm_tt_get_usermm(bo->tbo.ttm) && !bo->tbo.pin_count)
                amdgpu_bo_fence(bo,
                                &avm->process_info->eviction_fence->base,
                                true);
        ret = unreserve_bo_and_vms(&ctx, false, false);

        /* Only apply no TLB flush on Aldebaran to
         * workaround regressions on other Asics.
         */
        if (table_freed && (adev->asic_type != CHIP_ALDEBARAN))
                *table_freed = true;

        goto out;

out_unreserve:
        unreserve_bo_and_vms(&ctx, false, false);
out:
        mutex_unlock(&mem->process_info->lock);
        mutex_unlock(&mem->lock);
        return ret;
}

int amdgpu_amdkfd_gpuvm_unmap_memory_from_gpu(
                struct kgd_dev *kgd, struct kgd_mem *mem, void *drm_priv)
{
        struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
        struct amdkfd_process_info *process_info = avm->process_info;
        unsigned long bo_size = mem->bo->tbo.base.size;
        struct kfd_mem_attachment *entry;
        struct bo_vm_reservation_context ctx;
        int ret;

        mutex_lock(&mem->lock);

        ret = reserve_bo_and_cond_vms(mem, avm, BO_VM_MAPPED, &ctx);
        if (unlikely(ret))
                goto out;
        /* If no VMs were reserved, it means the BO wasn't actually mapped */
        if (ctx.n_vms == 0) {
                ret = -EINVAL;
                goto unreserve_out;
        }

        ret = vm_validate_pt_pd_bos(avm);
        if (unlikely(ret))
                goto unreserve_out;

        pr_debug("Unmap VA 0x%llx - 0x%llx from vm %p\n",
                mem->va,
                mem->va + bo_size * (1 + mem->aql_queue),
                avm);

        list_for_each_entry(entry, &mem->attachments, list) {
                if (entry->bo_va->base.vm != avm || !entry->is_mapped)
                        continue;

                pr_debug("\t unmap VA 0x%llx - 0x%llx from entry %p\n",
                         entry->va, entry->va + bo_size, entry);

                unmap_bo_from_gpuvm(mem, entry, ctx.sync);
                entry->is_mapped = false;

                mem->mapped_to_gpu_memory--;
                pr_debug("\t DEC mapping count %d\n",
                         mem->mapped_to_gpu_memory);
        }

        /* If BO is unmapped from all VMs, unfence it. It can be evicted if
         * required.
         */
        if (mem->mapped_to_gpu_memory == 0 &&
            !amdgpu_ttm_tt_get_usermm(mem->bo->tbo.ttm) &&
            !mem->bo->tbo.pin_count)
                amdgpu_amdkfd_remove_eviction_fence(mem->bo,
                                                process_info->eviction_fence);

unreserve_out:
        unreserve_bo_and_vms(&ctx, false, false);
out:
        mutex_unlock(&mem->lock);
        return ret;
}

int amdgpu_amdkfd_gpuvm_sync_memory(
                struct kgd_dev *kgd, struct kgd_mem *mem, bool intr)
{
        struct amdgpu_sync sync;
        int ret;

        amdgpu_sync_create(&sync);

        mutex_lock(&mem->lock);
        amdgpu_sync_clone(&mem->sync, &sync);
        mutex_unlock(&mem->lock);

        ret = amdgpu_sync_wait(&sync, intr);
        amdgpu_sync_free(&sync);
        return ret;
}

int amdgpu_amdkfd_gpuvm_map_gtt_bo_to_kernel(struct kgd_dev *kgd,
                struct kgd_mem *mem, void **kptr, uint64_t *size)
{
        int ret;
        struct amdgpu_bo *bo = mem->bo;

        if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) {
                pr_err("userptr can't be mapped to kernel\n");
                return -EINVAL;
        }

        /* delete kgd_mem from kfd_bo_list to avoid re-validating
         * this BO in BO's restoring after eviction.
         */
        mutex_lock(&mem->process_info->lock);

        ret = amdgpu_bo_reserve(bo, true);
        if (ret) {
                pr_err("Failed to reserve bo. ret %d\n", ret);
                goto bo_reserve_failed;
        }

        ret = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT);
        if (ret) {
                pr_err("Failed to pin bo. ret %d\n", ret);
                goto pin_failed;
        }

        ret = amdgpu_bo_kmap(bo, kptr);
        if (ret) {
                pr_err("Failed to map bo to kernel. ret %d\n", ret);
                goto kmap_failed;
        }

        amdgpu_amdkfd_remove_eviction_fence(
                bo, mem->process_info->eviction_fence);
        list_del_init(&mem->validate_list.head);

        if (size)
                *size = amdgpu_bo_size(bo);

        amdgpu_bo_unreserve(bo);

        mutex_unlock(&mem->process_info->lock);
        return 0;

kmap_failed:
        amdgpu_bo_unpin(bo);
pin_failed:
        amdgpu_bo_unreserve(bo);
bo_reserve_failed:
        mutex_unlock(&mem->process_info->lock);

        return ret;
}

void amdgpu_amdkfd_gpuvm_unmap_gtt_bo_from_kernel(struct kgd_dev *kgd, struct kgd_mem *mem)
{
        struct amdgpu_bo *bo = mem->bo;

        amdgpu_bo_reserve(bo, true);
        amdgpu_bo_kunmap(bo);
        amdgpu_bo_unpin(bo);
        amdgpu_bo_unreserve(bo);
}

int amdgpu_amdkfd_gpuvm_get_vm_fault_info(struct kgd_dev *kgd,
                                              struct kfd_vm_fault_info *mem)
{
        struct amdgpu_device *adev;

        adev = (struct amdgpu_device *)kgd;
        if (atomic_read(&adev->gmc.vm_fault_info_updated) == 1) {
                *mem = *adev->gmc.vm_fault_info;
                mb();
                atomic_set(&adev->gmc.vm_fault_info_updated, 0);
        }
        return 0;
}

int amdgpu_amdkfd_gpuvm_import_dmabuf(struct kgd_dev *kgd,
                                      struct dma_buf *dma_buf,
                                      uint64_t va, void *drm_priv,
                                      struct kgd_mem **mem, uint64_t *size,
                                      uint64_t *mmap_offset)
{
        struct amdgpu_device *adev = (struct amdgpu_device *)kgd;
        struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
        struct drm_gem_object *obj;
        struct amdgpu_bo *bo;
        int ret;

        if (dma_buf->ops != &amdgpu_dmabuf_ops)
                /* Can't handle non-graphics buffers */
                return -EINVAL;

        obj = dma_buf->priv;
        if (drm_to_adev(obj->dev) != adev)
                /* Can't handle buffers from other devices */
                return -EINVAL;

        bo = gem_to_amdgpu_bo(obj);
        if (!(bo->preferred_domains & (AMDGPU_GEM_DOMAIN_VRAM |
                                    AMDGPU_GEM_DOMAIN_GTT)))
                /* Only VRAM and GTT BOs are supported */
                return -EINVAL;

        *mem = kzalloc(sizeof(struct kgd_mem), GFP_KERNEL);
        if (!*mem)
                return -ENOMEM;

        ret = drm_vma_node_allow(&obj->vma_node, drm_priv);
        if (ret) {
                kfree(mem);
                return ret;
        }

        if (size)
                *size = amdgpu_bo_size(bo);

        if (mmap_offset)
                *mmap_offset = amdgpu_bo_mmap_offset(bo);

        INIT_LIST_HEAD(&(*mem)->attachments);
        mutex_init(&(*mem)->lock);

        (*mem)->alloc_flags =
                ((bo->preferred_domains & AMDGPU_GEM_DOMAIN_VRAM) ?
                KFD_IOC_ALLOC_MEM_FLAGS_VRAM : KFD_IOC_ALLOC_MEM_FLAGS_GTT)
                | KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE
                | KFD_IOC_ALLOC_MEM_FLAGS_EXECUTABLE;

        drm_gem_object_get(&bo->tbo.base);
        (*mem)->bo = bo;
        (*mem)->va = va;
        (*mem)->domain = (bo->preferred_domains & AMDGPU_GEM_DOMAIN_VRAM) ?
                AMDGPU_GEM_DOMAIN_VRAM : AMDGPU_GEM_DOMAIN_GTT;
        (*mem)->mapped_to_gpu_memory = 0;
        (*mem)->process_info = avm->process_info;
        add_kgd_mem_to_kfd_bo_list(*mem, avm->process_info, false);
        amdgpu_sync_create(&(*mem)->sync);
        (*mem)->is_imported = true;

        return 0;
}

/* Evict a userptr BO by stopping the queues if necessary
 *
 * Runs in MMU notifier, may be in RECLAIM_FS context. This means it
 * cannot do any memory allocations, and cannot take any locks that
 * are held elsewhere while allocating memory. Therefore this is as
 * simple as possible, using atomic counters.
 *
 * It doesn't do anything to the BO itself. The real work happens in
 * restore, where we get updated page addresses. This function only
 * ensures that GPU access to the BO is stopped.
 */
int amdgpu_amdkfd_evict_userptr(struct kgd_mem *mem,
                                struct mm_struct *mm)
{
        struct amdkfd_process_info *process_info = mem->process_info;
        int evicted_bos;
        int r = 0;

        atomic_inc(&mem->invalid);
        evicted_bos = atomic_inc_return(&process_info->evicted_bos);
        if (evicted_bos == 1) {
                /* First eviction, stop the queues */
                r = kgd2kfd_quiesce_mm(mm);
                if (r)
                        pr_err("Failed to quiesce KFD\n");
                schedule_delayed_work(&process_info->restore_userptr_work,
                        msecs_to_jiffies(AMDGPU_USERPTR_RESTORE_DELAY_MS));
        }

        return r;
}

/* Update invalid userptr BOs
 *
 * Moves invalidated (evicted) userptr BOs from userptr_valid_list to
 * userptr_inval_list and updates user pages for all BOs that have
 * been invalidated since their last update.
 */
static int update_invalid_user_pages(struct amdkfd_process_info *process_info,
                                     struct mm_struct *mm)
{
        struct kgd_mem *mem, *tmp_mem;
        struct amdgpu_bo *bo;
        struct ttm_operation_ctx ctx = { false, false };
        int invalid, ret;

        /* Move all invalidated BOs to the userptr_inval_list and
         * release their user pages by migration to the CPU domain
         */
        list_for_each_entry_safe(mem, tmp_mem,
                                 &process_info->userptr_valid_list,
                                 validate_list.head) {
                if (!atomic_read(&mem->invalid))
                        continue; /* BO is still valid */

                bo = mem->bo;

                if (amdgpu_bo_reserve(bo, true))
                        return -EAGAIN;
                amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
                ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
                amdgpu_bo_unreserve(bo);
                if (ret) {
                        pr_err("%s: Failed to invalidate userptr BO\n",
                               __func__);
                        return -EAGAIN;
                }

                list_move_tail(&mem->validate_list.head,
                               &process_info->userptr_inval_list);
        }

        if (list_empty(&process_info->userptr_inval_list))
                return 0; /* All evicted userptr BOs were freed */

        /* Go through userptr_inval_list and update any invalid user_pages */
        list_for_each_entry(mem, &process_info->userptr_inval_list,
                            validate_list.head) {
                invalid = atomic_read(&mem->invalid);
                if (!invalid)
                        /* BO hasn't been invalidated since the last
                         * revalidation attempt. Keep its BO list.
                         */
                        continue;

                bo = mem->bo;

                /* Get updated user pages */
                ret = amdgpu_ttm_tt_get_user_pages(bo, bo->tbo.ttm->pages);
                if (ret) {
                        pr_debug("Failed %d to get user pages\n", ret);

                        /* Return -EFAULT bad address error as success. It will
                         * fail later with a VM fault if the GPU tries to access
                         * it. Better than hanging indefinitely with stalled
                         * user mode queues.
                         *
                         * Return other error -EBUSY or -ENOMEM to retry restore
                         */
                        if (ret != -EFAULT)
                                return ret;
                } else {

                        /*
                         * FIXME: Cannot ignore the return code, must hold
                         * notifier_lock
                         */
                        amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
                }

                /* Mark the BO as valid unless it was invalidated
                 * again concurrently.
                 */
                if (atomic_cmpxchg(&mem->invalid, invalid, 0) != invalid)
                        return -EAGAIN;
        }

        return 0;
}

/* Validate invalid userptr BOs
 *
 * Validates BOs on the userptr_inval_list, and moves them back to the
 * userptr_valid_list. Also updates GPUVM page tables with new page
 * addresses and waits for the page table updates to complete.
 */
static int validate_invalid_user_pages(struct amdkfd_process_info *process_info)
{
        struct amdgpu_bo_list_entry *pd_bo_list_entries;
        struct list_head resv_list, duplicates;
        struct ww_acquire_ctx ticket;
        struct amdgpu_sync sync;

        struct amdgpu_vm *peer_vm;
        struct kgd_mem *mem, *tmp_mem;
        struct amdgpu_bo *bo;
        struct ttm_operation_ctx ctx = { false, false };
        int i, ret;

        pd_bo_list_entries = kcalloc(process_info->n_vms,
                                     sizeof(struct amdgpu_bo_list_entry),
                                     GFP_KERNEL);
        if (!pd_bo_list_entries) {
                pr_err("%s: Failed to allocate PD BO list entries\n", __func__);
                ret = -ENOMEM;
                goto out_no_mem;
        }

        INIT_LIST_HEAD(&resv_list);
        INIT_LIST_HEAD(&duplicates);

        /* Get all the page directory BOs that need to be reserved */
        i = 0;
        list_for_each_entry(peer_vm, &process_info->vm_list_head,
                            vm_list_node)
                amdgpu_vm_get_pd_bo(peer_vm, &resv_list,
                                    &pd_bo_list_entries[i++]);
        /* Add the userptr_inval_list entries to resv_list */
        list_for_each_entry(mem, &process_info->userptr_inval_list,
                            validate_list.head) {
                list_add_tail(&mem->resv_list.head, &resv_list);
                mem->resv_list.bo = mem->validate_list.bo;
                mem->resv_list.num_shared = mem->validate_list.num_shared;
        }

        /* Reserve all BOs and page tables for validation */
        ret = ttm_eu_reserve_buffers(&ticket, &resv_list, false, &duplicates);
        WARN(!list_empty(&duplicates), "Duplicates should be empty");
        if (ret)
                goto out_free;

        amdgpu_sync_create(&sync);

        ret = process_validate_vms(process_info);
        if (ret)
                goto unreserve_out;

        /* Validate BOs and update GPUVM page tables */
        list_for_each_entry_safe(mem, tmp_mem,
                                 &process_info->userptr_inval_list,
                                 validate_list.head) {
                struct kfd_mem_attachment *attachment;

                bo = mem->bo;

                /* Validate the BO if we got user pages */
                if (bo->tbo.ttm->pages[0]) {
                        amdgpu_bo_placement_from_domain(bo, mem->domain);
                        ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
                        if (ret) {
                                pr_err("%s: failed to validate BO\n", __func__);
                                goto unreserve_out;
                        }
                }

                list_move_tail(&mem->validate_list.head,
                               &process_info->userptr_valid_list);

                /* Update mapping. If the BO was not validated
                 * (because we couldn't get user pages), this will
                 * clear the page table entries, which will result in
                 * VM faults if the GPU tries to access the invalid
                 * memory.
                 */
                list_for_each_entry(attachment, &mem->attachments, list) {
                        if (!attachment->is_mapped)
                                continue;

                        kfd_mem_dmaunmap_attachment(mem, attachment);
                        ret = update_gpuvm_pte(mem, attachment, &sync, NULL);
                        if (ret) {
                                pr_err("%s: update PTE failed\n", __func__);
                                /* make sure this gets validated again */
                                atomic_inc(&mem->invalid);
                                goto unreserve_out;
                        }
                }
        }

        /* Update page directories */
        ret = process_update_pds(process_info, &sync);

unreserve_out:
        ttm_eu_backoff_reservation(&ticket, &resv_list);
        amdgpu_sync_wait(&sync, false);
        amdgpu_sync_free(&sync);
out_free:
        kfree(pd_bo_list_entries);
out_no_mem:

        return ret;
}

/* Worker callback to restore evicted userptr BOs
 *
 * Tries to update and validate all userptr BOs. If successful and no
 * concurrent evictions happened, the queues are restarted. Otherwise,
 * reschedule for another attempt later.
 */
static void amdgpu_amdkfd_restore_userptr_worker(struct work_struct *work)
{
        struct delayed_work *dwork = to_delayed_work(work);
        struct amdkfd_process_info *process_info =
                container_of(dwork, struct amdkfd_process_info,
                             restore_userptr_work);
        struct task_struct *usertask;
        struct mm_struct *mm;
        int evicted_bos;

        evicted_bos = atomic_read(&process_info->evicted_bos);
        if (!evicted_bos)
                return;

        /* Reference task and mm in case of concurrent process termination */
        usertask = get_pid_task(process_info->pid, PIDTYPE_PID);
        if (!usertask)
                return;
        mm = get_task_mm(usertask);
        if (!mm) {
                put_task_struct(usertask);
                return;
        }

        mutex_lock(&process_info->lock);

        if (update_invalid_user_pages(process_info, mm))
                goto unlock_out;
        /* userptr_inval_list can be empty if all evicted userptr BOs
         * have been freed. In that case there is nothing to validate
         * and we can just restart the queues.
         */
        if (!list_empty(&process_info->userptr_inval_list)) {
                if (atomic_read(&process_info->evicted_bos) != evicted_bos)
                        goto unlock_out; /* Concurrent eviction, try again */

                if (validate_invalid_user_pages(process_info))
                        goto unlock_out;
        }
        /* Final check for concurrent evicton and atomic update. If
         * another eviction happens after successful update, it will
         * be a first eviction that calls quiesce_mm. The eviction
         * reference counting inside KFD will handle this case.
         */
        if (atomic_cmpxchg(&process_info->evicted_bos, evicted_bos, 0) !=
            evicted_bos)
                goto unlock_out;
        evicted_bos = 0;
        if (kgd2kfd_resume_mm(mm)) {
                pr_err("%s: Failed to resume KFD\n", __func__);
                /* No recovery from this failure. Probably the CP is
                 * hanging. No point trying again.
                 */
        }

unlock_out:
        mutex_unlock(&process_info->lock);
        mmput(mm);
        put_task_struct(usertask);

        /* If validation failed, reschedule another attempt */
        if (evicted_bos)
                schedule_delayed_work(&process_info->restore_userptr_work,
                        msecs_to_jiffies(AMDGPU_USERPTR_RESTORE_DELAY_MS));
}

/** amdgpu_amdkfd_gpuvm_restore_process_bos - Restore all BOs for the given
 *   KFD process identified by process_info
 *
 * @process_info: amdkfd_process_info of the KFD process
 *
 * After memory eviction, restore thread calls this function. The function
 * should be called when the Process is still valid. BO restore involves -
 *
 * 1.  Release old eviction fence and create new one
 * 2.  Get two copies of PD BO list from all the VMs. Keep one copy as pd_list.
 * 3   Use the second PD list and kfd_bo_list to create a list (ctx.list) of
 *     BOs that need to be reserved.
 * 4.  Reserve all the BOs
 * 5.  Validate of PD and PT BOs.
 * 6.  Validate all KFD BOs using kfd_bo_list and Map them and add new fence
 * 7.  Add fence to all PD and PT BOs.
 * 8.  Unreserve all BOs
 */
int amdgpu_amdkfd_gpuvm_restore_process_bos(void *info, struct dma_fence **ef)
{
        struct amdgpu_bo_list_entry *pd_bo_list;
        struct amdkfd_process_info *process_info = info;
        struct amdgpu_vm *peer_vm;
        struct kgd_mem *mem;
        struct bo_vm_reservation_context ctx;
        struct amdgpu_amdkfd_fence *new_fence;
        int ret = 0, i;
        struct list_head duplicate_save;
        struct amdgpu_sync sync_obj;
        unsigned long failed_size = 0;
        unsigned long total_size = 0;

        INIT_LIST_HEAD(&duplicate_save);
        INIT_LIST_HEAD(&ctx.list);
        INIT_LIST_HEAD(&ctx.duplicates);

        pd_bo_list = kcalloc(process_info->n_vms,
                             sizeof(struct amdgpu_bo_list_entry),
                             GFP_KERNEL);
        if (!pd_bo_list)
                return -ENOMEM;

        i = 0;
        mutex_lock(&process_info->lock);
        list_for_each_entry(peer_vm, &process_info->vm_list_head,
                        vm_list_node)
                amdgpu_vm_get_pd_bo(peer_vm, &ctx.list, &pd_bo_list[i++]);

        /* Reserve all BOs and page tables/directory. Add all BOs from
         * kfd_bo_list to ctx.list
         */
        list_for_each_entry(mem, &process_info->kfd_bo_list,
                            validate_list.head) {

                list_add_tail(&mem->resv_list.head, &ctx.list);
                mem->resv_list.bo = mem->validate_list.bo;
                mem->resv_list.num_shared = mem->validate_list.num_shared;
        }

        ret = ttm_eu_reserve_buffers(&ctx.ticket, &ctx.list,
                                     false, &duplicate_save);
        if (ret) {
                pr_debug("Memory eviction: TTM Reserve Failed. Try again\n");
                goto ttm_reserve_fail;
        }

        amdgpu_sync_create(&sync_obj);

        /* Validate PDs and PTs */
        ret = process_validate_vms(process_info);
        if (ret)
                goto validate_map_fail;

        ret = process_sync_pds_resv(process_info, &sync_obj);
        if (ret) {
                pr_debug("Memory eviction: Failed to sync to PD BO moving fence. Try again\n");
                goto validate_map_fail;
        }

        /* Validate BOs and map them to GPUVM (update VM page tables). */
        list_for_each_entry(mem, &process_info->kfd_bo_list,
                            validate_list.head) {

                struct amdgpu_bo *bo = mem->bo;
                uint32_t domain = mem->domain;
                struct kfd_mem_attachment *attachment;

                total_size += amdgpu_bo_size(bo);

                ret = amdgpu_amdkfd_bo_validate(bo, domain, false);
                if (ret) {
                        pr_debug("Memory eviction: Validate BOs failed\n");
                        failed_size += amdgpu_bo_size(bo);
                        ret = amdgpu_amdkfd_bo_validate(bo,
                                                AMDGPU_GEM_DOMAIN_GTT, false);
                        if (ret) {
                                pr_debug("Memory eviction: Try again\n");
                                goto validate_map_fail;
                        }
                }
                ret = amdgpu_sync_fence(&sync_obj, bo->tbo.moving);
                if (ret) {
                        pr_debug("Memory eviction: Sync BO fence failed. Try again\n");
                        goto validate_map_fail;
                }
                list_for_each_entry(attachment, &mem->attachments, list) {
                        if (!attachment->is_mapped)
                                continue;

                        kfd_mem_dmaunmap_attachment(mem, attachment);
                        ret = update_gpuvm_pte(mem, attachment, &sync_obj, NULL);
                        if (ret) {
                                pr_debug("Memory eviction: update PTE failed. Try again\n");
                                goto validate_map_fail;
                        }
                }
        }

        if (failed_size)
                pr_debug("0x%lx/0x%lx in system\n", failed_size, total_size);

        /* Update page directories */
        ret = process_update_pds(process_info, &sync_obj);
        if (ret) {
                pr_debug("Memory eviction: update PDs failed. Try again\n");
                goto validate_map_fail;
        }

        /* Wait for validate and PT updates to finish */
        amdgpu_sync_wait(&sync_obj, false);

        /* Release old eviction fence and create new one, because fence only
         * goes from unsignaled to signaled, fence cannot be reused.
         * Use context and mm from the old fence.
         */
        new_fence = amdgpu_amdkfd_fence_create(
                                process_info->eviction_fence->base.context,
                                process_info->eviction_fence->mm,
                                NULL);
        if (!new_fence) {
                pr_err("Failed to create eviction fence\n");
                ret = -ENOMEM;
                goto validate_map_fail;
        }
        dma_fence_put(&process_info->eviction_fence->base);
        process_info->eviction_fence = new_fence;
        *ef = dma_fence_get(&new_fence->base);

        /* Attach new eviction fence to all BOs */
        list_for_each_entry(mem, &process_info->kfd_bo_list,
                validate_list.head)
                amdgpu_bo_fence(mem->bo,
                        &process_info->eviction_fence->base, true);

        /* Attach eviction fence to PD / PT BOs */
        list_for_each_entry(peer_vm, &process_info->vm_list_head,
                            vm_list_node) {
                struct amdgpu_bo *bo = peer_vm->root.bo;

                amdgpu_bo_fence(bo, &process_info->eviction_fence->base, true);
        }

validate_map_fail:
        ttm_eu_backoff_reservation(&ctx.ticket, &ctx.list);
        amdgpu_sync_free(&sync_obj);
ttm_reserve_fail:
        mutex_unlock(&process_info->lock);
        kfree(pd_bo_list);
        return ret;
}

int amdgpu_amdkfd_add_gws_to_process(void *info, void *gws, struct kgd_mem **mem)
{
        struct amdkfd_process_info *process_info = (struct amdkfd_process_info *)info;
        struct amdgpu_bo *gws_bo = (struct amdgpu_bo *)gws;
        int ret;

        if (!info || !gws)
                return -EINVAL;

        *mem = kzalloc(sizeof(struct kgd_mem), GFP_KERNEL);
        if (!*mem)
                return -ENOMEM;

        mutex_init(&(*mem)->lock);
        INIT_LIST_HEAD(&(*mem)->attachments);
        (*mem)->bo = amdgpu_bo_ref(gws_bo);
        (*mem)->domain = AMDGPU_GEM_DOMAIN_GWS;
        (*mem)->process_info = process_info;
        add_kgd_mem_to_kfd_bo_list(*mem, process_info, false);
        amdgpu_sync_create(&(*mem)->sync);


        /* Validate gws bo the first time it is added to process */
        mutex_lock(&(*mem)->process_info->lock);
        ret = amdgpu_bo_reserve(gws_bo, false);
        if (unlikely(ret)) {
                pr_err("Reserve gws bo failed %d\n", ret);
                goto bo_reservation_failure;
        }

        ret = amdgpu_amdkfd_bo_validate(gws_bo, AMDGPU_GEM_DOMAIN_GWS, true);
        if (ret) {
                pr_err("GWS BO validate failed %d\n", ret);
                goto bo_validation_failure;
        }
        /* GWS resource is shared b/t amdgpu and amdkfd
         * Add process eviction fence to bo so they can
         * evict each other.
         */
        ret = dma_resv_reserve_shared(gws_bo->tbo.base.resv, 1);
        if (ret)
                goto reserve_shared_fail;
        amdgpu_bo_fence(gws_bo, &process_info->eviction_fence->base, true);
        amdgpu_bo_unreserve(gws_bo);
        mutex_unlock(&(*mem)->process_info->lock);

        return ret;

reserve_shared_fail:
bo_validation_failure:
        amdgpu_bo_unreserve(gws_bo);
bo_reservation_failure:
        mutex_unlock(&(*mem)->process_info->lock);
        amdgpu_sync_free(&(*mem)->sync);
        remove_kgd_mem_from_kfd_bo_list(*mem, process_info);
        amdgpu_bo_unref(&gws_bo);
        mutex_destroy(&(*mem)->lock);
        kfree(*mem);
        *mem = NULL;
        return ret;
}

int amdgpu_amdkfd_remove_gws_from_process(void *info, void *mem)
{
        int ret;
        struct amdkfd_process_info *process_info = (struct amdkfd_process_info *)info;
        struct kgd_mem *kgd_mem = (struct kgd_mem *)mem;
        struct amdgpu_bo *gws_bo = kgd_mem->bo;

        /* Remove BO from process's validate list so restore worker won't touch
         * it anymore
         */
        remove_kgd_mem_from_kfd_bo_list(kgd_mem, process_info);

        ret = amdgpu_bo_reserve(gws_bo, false);
        if (unlikely(ret)) {
                pr_err("Reserve gws bo failed %d\n", ret);
                //TODO add BO back to validate_list?
                return ret;
        }
        amdgpu_amdkfd_remove_eviction_fence(gws_bo,
                        process_info->eviction_fence);
        amdgpu_bo_unreserve(gws_bo);
        amdgpu_sync_free(&kgd_mem->sync);
        amdgpu_bo_unref(&gws_bo);
        mutex_destroy(&kgd_mem->lock);
        kfree(mem);
        return 0;
}

/* Returns GPU-specific tiling mode information */
int amdgpu_amdkfd_get_tile_config(struct kgd_dev *kgd,
                                struct tile_config *config)
{
        struct amdgpu_device *adev = (struct amdgpu_device *)kgd;

        config->gb_addr_config = adev->gfx.config.gb_addr_config;
        config->tile_config_ptr = adev->gfx.config.tile_mode_array;
        config->num_tile_configs =
                        ARRAY_SIZE(adev->gfx.config.tile_mode_array);
        config->macro_tile_config_ptr =
                        adev->gfx.config.macrotile_mode_array;
        config->num_macro_tile_configs =
                        ARRAY_SIZE(adev->gfx.config.macrotile_mode_array);

        /* Those values are not set from GFX9 onwards */
        config->num_banks = adev->gfx.config.num_banks;
        config->num_ranks = adev->gfx.config.num_ranks;

        return 0;
}