1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Shared Memory Communications over RDMA (SMC-R) and RoCE
4 *
5 * smc_sysctl.c: sysctl interface to SMC subsystem.
6 *
7 * Copyright (c) 2022, Alibaba Inc.
8 *
9 * Author: Tony Lu <tonylu@linux.alibaba.com>
10 *
11 */
12
13 #include <linux/init.h>
14 #include <linux/sysctl.h>
15 #include <net/net_namespace.h>
16
17 #include "smc.h"
18 #include "smc_core.h"
19 #include "smc_llc.h"
20 #include "smc_sysctl.h"
21
22 static int min_sndbuf = SMC_BUF_MIN_SIZE;
23 static int min_rcvbuf = SMC_BUF_MIN_SIZE;
24 static int max_sndbuf = INT_MAX / 2;
25 static int max_rcvbuf = INT_MAX / 2;
26 static const int net_smc_wmem_init = (64 * 1024);
27 static const int net_smc_rmem_init = (64 * 1024);
28 static int links_per_lgr_min = SMC_LINKS_ADD_LNK_MIN;
29 static int links_per_lgr_max = SMC_LINKS_ADD_LNK_MAX;
30 static int conns_per_lgr_min = SMC_CONN_PER_LGR_MIN;
31 static int conns_per_lgr_max = SMC_CONN_PER_LGR_MAX;
32
33 static struct ctl_table smc_table[] = {
34 {
35 .procname = "autocorking_size",
36 .data = &init_net.smc.sysctl_autocorking_size,
37 .maxlen = sizeof(unsigned int),
38 .mode = 0644,
39 .proc_handler = proc_douintvec,
40 },
41 {
42 .procname = "smcr_buf_type",
43 .data = &init_net.smc.sysctl_smcr_buf_type,
44 .maxlen = sizeof(unsigned int),
45 .mode = 0644,
46 .proc_handler = proc_douintvec_minmax,
47 .extra1 = SYSCTL_ZERO,
48 .extra2 = SYSCTL_TWO,
49 },
50 {
51 .procname = "smcr_testlink_time",
52 .data = &init_net.smc.sysctl_smcr_testlink_time,
53 .maxlen = sizeof(int),
54 .mode = 0644,
55 .proc_handler = proc_dointvec_jiffies,
56 },
57 {
58 .procname = "wmem",
59 .data = &init_net.smc.sysctl_wmem,
60 .maxlen = sizeof(int),
61 .mode = 0644,
62 .proc_handler = proc_dointvec_minmax,
63 .extra1 = &min_sndbuf,
64 .extra2 = &max_sndbuf,
65 },
66 {
67 .procname = "rmem",
68 .data = &init_net.smc.sysctl_rmem,
69 .maxlen = sizeof(int),
70 .mode = 0644,
71 .proc_handler = proc_dointvec_minmax,
72 .extra1 = &min_rcvbuf,
73 .extra2 = &max_rcvbuf,
74 },
75 {
76 .procname = "smcr_max_links_per_lgr",
77 .data = &init_net.smc.sysctl_max_links_per_lgr,
78 .maxlen = sizeof(int),
79 .mode = 0644,
80 .proc_handler = proc_dointvec_minmax,
81 .extra1 = &links_per_lgr_min,
82 .extra2 = &links_per_lgr_max,
83 },
84 {
85 .procname = "smcr_max_conns_per_lgr",
86 .data = &init_net.smc.sysctl_max_conns_per_lgr,
87 .maxlen = sizeof(int),
88 .mode = 0644,
89 .proc_handler = proc_dointvec_minmax,
90 .extra1 = &conns_per_lgr_min,
91 .extra2 = &conns_per_lgr_max,
92 },
93 {
94 .procname = "limit_smc_hs",
95 .data = &init_net.smc.limit_smc_hs,
96 .maxlen = sizeof(int),
97 .mode = 0644,
98 .proc_handler = proc_dointvec_minmax,
99 .extra1 = SYSCTL_ZERO,
100 .extra2 = SYSCTL_ONE,
101 },
102 };
103
smc_sysctl_net_init(struct net * net)104 int __net_init smc_sysctl_net_init(struct net *net)
105 {
106 size_t table_size = ARRAY_SIZE(smc_table);
107 struct ctl_table *table;
108
109 table = smc_table;
110 if (!net_eq(net, &init_net)) {
111 int i;
112
113 table = kmemdup(table, sizeof(smc_table), GFP_KERNEL);
114 if (!table)
115 goto err_alloc;
116
117 for (i = 0; i < table_size; i++)
118 table[i].data += (void *)net - (void *)&init_net;
119 }
120
121 net->smc.smc_hdr = register_net_sysctl_sz(net, "net/smc", table,
122 table_size);
123 if (!net->smc.smc_hdr)
124 goto err_reg;
125
126 net->smc.sysctl_autocorking_size = SMC_AUTOCORKING_DEFAULT_SIZE;
127 net->smc.sysctl_smcr_buf_type = SMCR_PHYS_CONT_BUFS;
128 net->smc.sysctl_smcr_testlink_time = SMC_LLC_TESTLINK_DEFAULT_TIME;
129 WRITE_ONCE(net->smc.sysctl_wmem, net_smc_wmem_init);
130 WRITE_ONCE(net->smc.sysctl_rmem, net_smc_rmem_init);
131 net->smc.sysctl_max_links_per_lgr = SMC_LINKS_PER_LGR_MAX_PREFER;
132 net->smc.sysctl_max_conns_per_lgr = SMC_CONN_PER_LGR_PREFER;
133 /* disable handshake limitation by default */
134 net->smc.limit_smc_hs = 0;
135
136 return 0;
137
138 err_reg:
139 if (!net_eq(net, &init_net))
140 kfree(table);
141 err_alloc:
142 return -ENOMEM;
143 }
144
smc_sysctl_net_exit(struct net * net)145 void __net_exit smc_sysctl_net_exit(struct net *net)
146 {
147 const struct ctl_table *table;
148
149 table = net->smc.smc_hdr->ctl_table_arg;
150 unregister_net_sysctl_table(net->smc.smc_hdr);
151 if (!net_eq(net, &init_net))
152 kfree(table);
153 }
154