dmah.c

 1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
 2/*
 3 * Copyright (c) 2025, NVIDIA CORPORATION & AFFILIATES. All rights reserved
 4 */
 5
 6#include <rdma/uverbs_std_types.h>
 7#include <linux/pci-tph.h>
 8#include "dmah.h"
 9
10#define UVERBS_MODULE_NAME mlx5_ib
11#include <rdma/uverbs_named_ioctl.h>
12
13static int mlx5_ib_alloc_dmah(struct ib_dmah *ibdmah,
14			      struct uverbs_attr_bundle *attrs)
15{
16	struct mlx5_core_dev *mdev = to_mdev(ibdmah->device)->mdev;
17	struct mlx5_ib_dmah *dmah = to_mdmah(ibdmah);
18	u16 st_bits = BIT(IB_DMAH_CPU_ID_EXISTS) |
19		      BIT(IB_DMAH_MEM_TYPE_EXISTS);
20	int err;
21
22	/* PH is a must for TPH following PCIe spec 6.2-1.0 */
23	if (!(ibdmah->valid_fields & BIT(IB_DMAH_PH_EXISTS)))
24		return -EINVAL;
25
26	/* ST is optional; however, partial data for it is not allowed */
27	if (ibdmah->valid_fields & st_bits) {
28		if ((ibdmah->valid_fields & st_bits) != st_bits)
29			return -EINVAL;
30		err = mlx5_st_alloc_index(mdev, ibdmah->mem_type,
31					  ibdmah->cpu_id, &dmah->st_index);
32		if (err)
33			return err;
34	}
35
36	return 0;
37}
38
39static int mlx5_ib_dealloc_dmah(struct ib_dmah *ibdmah,
40				struct uverbs_attr_bundle *attrs)
41{
42	struct mlx5_ib_dmah *dmah = to_mdmah(ibdmah);
43	struct mlx5_core_dev *mdev = to_mdev(ibdmah->device)->mdev;
44
45	if (ibdmah->valid_fields & BIT(IB_DMAH_CPU_ID_EXISTS))
46		return mlx5_st_dealloc_index(mdev, dmah->st_index);
47
48	return 0;
49}
50
51const struct ib_device_ops mlx5_ib_dev_dmah_ops = {
52	.alloc_dmah = mlx5_ib_alloc_dmah,
53	.dealloc_dmah = mlx5_ib_dealloc_dmah,
54};