text: /**
   * Copyright (C) Mellanox Technologies Ltd. 2017-2019.  ALL RIGHTS RESERVED.
   * See file LICENSE for terms.
   */
  
  #ifdef HAVE_CONFIG_H
  #  include "config.h"
  #endif
  
  #include "cuda_copy_md.h"
  
  #include <string.h>
  #include <limits.h>
  #include <ucs/debug/log.h>
  #include <ucs/sys/sys.h>
  #include <ucs/debug/memtrack.h>
  #include <ucs/type/class.h>
  #include <ucs/profile/profile.h>
  #include <uct/cuda/base/cuda_iface.h>
  #include <cuda_runtime.h>
  #include <cuda.h>
  
  
  static ucs_config_field_t uct_cuda_copy_md_config_table[] = {
      {"", "", NULL,
          ucs_offsetof(uct_cuda_copy_md_config_t, super), UCS_CONFIG_TYPE_TABLE(uct_md_config_table)},
  
      {NULL}
  };
  
  static ucs_status_t uct_cuda_copy_md_query(uct_md_h md, uct_md_attr_t *md_attr)
  {
      md_attr->cap.flags            = UCT_MD_FLAG_REG;
      md_attr->cap.reg_mem_types    = UCS_BIT(UCS_MEMORY_TYPE_HOST);
      md_attr->cap.access_mem_types = UCS_BIT(UCS_MEMORY_TYPE_CUDA);
      md_attr->cap.detect_mem_types = UCS_BIT(UCS_MEMORY_TYPE_CUDA) |
                                      UCS_BIT(UCS_MEMORY_TYPE_CUDA_MANAGED);
      md_attr->cap.max_alloc        = 0;
      md_attr->cap.max_reg          = ULONG_MAX;
      md_attr->rkey_packed_size     = 0;
      md_attr->reg_cost             = ucs_linear_func_make(0, 0);
      memset(&md_attr->local_cpus, 0xff, sizeof(md_attr->local_cpus));
      return UCS_OK;
  }
  
  static ucs_status_t uct_cuda_copy_mkey_pack(uct_md_h md, uct_mem_h memh,
                                              void *rkey_buffer)
  {
      return UCS_OK;
  }
  
  static ucs_status_t uct_cuda_copy_rkey_unpack(uct_component_t *component,
                                                const void *rkey_buffer,
                                                uct_rkey_t *rkey_p,
                                                void **handle_p)
  {
      *rkey_p   = 0xdeadbeef;
      *handle_p = NULL;
      return UCS_OK;
  }
  
  static ucs_status_t uct_cuda_copy_rkey_release(uct_component_t *component,
                                                 uct_rkey_t rkey, void *handle)
  {
      return UCS_OK;
  }
  
  UCS_PROFILE_FUNC(ucs_status_t, uct_cuda_copy_mem_reg,
                   (md, address, length, flags, memh_p),
                   uct_md_h md, void *address, size_t length,
                   unsigned flags, uct_mem_h *memh_p)
  {
      ucs_log_level_t log_level;
      CUmemorytype memType;
      CUresult result;
      ucs_status_t status;
  
      if (address == NULL) {
          *memh_p = address;
          return UCS_OK;
      }
  
      result = cuPointerGetAttribute(&memType, CU_POINTER_ATTRIBUTE_MEMORY_TYPE,
                                     (CUdeviceptr)(address));
      if ((result == CUDA_SUCCESS) && (memType == CU_MEMORYTYPE_HOST)) {
          /* memory is allocated with cudaMallocHost which is already registered */
          *memh_p = NULL;
          return UCS_OK;
      }
  
      log_level = (flags & UCT_MD_MEM_FLAG_HIDE_ERRORS) ? UCS_LOG_LEVEL_DEBUG :
                  UCS_LOG_LEVEL_ERROR;
      status    = UCT_CUDA_FUNC(cudaHostRegister(address, length,
                                                 cudaHostRegisterPortable),
                                log_level);
      if (status != UCS_OK) {
          return status;
      }
  
      *memh_p = address;
      return UCS_OK;
  }
  
  UCS_PROFILE_FUNC(ucs_status_t, uct_cuda_copy_mem_dereg,
                   (md, memh), uct_md_h md, uct_mem_h memh)
  {
      void *address = (void *)memh;
      ucs_status_t status;
  
      if (address == NULL) {
          return UCS_OK;
      }
  
      status = UCT_CUDA_FUNC_LOG_ERR(cudaHostUnregister(address));
      if (status != UCS_OK) {
          return status;
      }
  
      return UCS_OK;
  }
  
  static void uct_cuda_copy_md_close(uct_md_h uct_md) {
      uct_cuda_copy_md_t *md = ucs_derived_of(uct_md, uct_cuda_copy_md_t);
  
      ucs_free(md);
  }
  
  static uct_md_ops_t md_ops = {
      .close               = uct_cuda_copy_md_close,
      .query               = uct_cuda_copy_md_query,
      .mkey_pack           = uct_cuda_copy_mkey_pack,
      .mem_reg             = uct_cuda_copy_mem_reg,
      .mem_dereg           = uct_cuda_copy_mem_dereg,
      .mem_query           = uct_cuda_base_mem_query,
      .detect_memory_type  = uct_cuda_base_detect_memory_type,
  };
  
  static ucs_status_t
  uct_cuda_copy_md_open(uct_component_t *component, const char *md_name,
                        const uct_md_config_t *config, uct_md_h *md_p)
  {
      uct_cuda_copy_md_t *md;
  
      md = ucs_malloc(sizeof(uct_cuda_copy_md_t), "uct_cuda_copy_md_t");
      if (NULL == md) {
          ucs_error("failed to allocate memory for uct_cuda_copy_md_t");
          return UCS_ERR_NO_MEMORY;
      }
  
      md->super.ops       = &md_ops;
      md->super.component = &uct_cuda_copy_component;
      *md_p               = (uct_md_h)md;
      return UCS_OK;
  }
  
  uct_component_t uct_cuda_copy_component = {
      .query_md_resources = uct_cuda_base_query_md_resources,
      .md_open            = uct_cuda_copy_md_open,
      .cm_open            = ucs_empty_function_return_unsupported,
      .rkey_unpack        = uct_cuda_copy_rkey_unpack,
      .rkey_ptr           = ucs_empty_function_return_unsupported,
      .rkey_release       = uct_cuda_copy_rkey_release,
      .name               = "cuda_cpy",
      .md_config          = {
          .name           = "Cuda-copy memory domain",
          .prefix         = "CUDA_COPY_",
          .table          = uct_cuda_copy_md_config_table,
          .size           = sizeof(uct_cuda_copy_md_config_t),
      },
      .cm_config          = UCS_CONFIG_EMPTY_GLOBAL_LIST_ENTRY,
      .tl_list            = UCT_COMPONENT_TL_LIST_INITIALIZER(&uct_cuda_copy_component),
      .flags              = 0
  };
  UCT_COMPONENT_REGISTER(&uct_cuda_copy_component);
  
  