xref: /linux/drivers/infiniband/hw/mlx5/dmah.c (revision 8d2b0853add1d7534dc0794e3c8e0b9e8c4ec640)
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 
13 static 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 
39 static 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 
51 const struct ib_device_ops mlx5_ib_dev_dmah_ops = {
52 	.alloc_dmah = mlx5_ib_alloc_dmah,
53 	.dealloc_dmah = mlx5_ib_dealloc_dmah,
54 };
55