xref: /linux/net/smc/smc_sysctl.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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 
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 
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