xref: /linux/net/smc/smc_sysctl.c (revision 7effbd18e496a954540fb6319db0d87d28a70496)
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 
25 static struct ctl_table smc_table[] = {
26 	{
27 		.procname       = "autocorking_size",
28 		.data           = &init_net.smc.sysctl_autocorking_size,
29 		.maxlen         = sizeof(unsigned int),
30 		.mode           = 0644,
31 		.proc_handler	= proc_douintvec,
32 	},
33 	{
34 		.procname	= "smcr_buf_type",
35 		.data		= &init_net.smc.sysctl_smcr_buf_type,
36 		.maxlen		= sizeof(unsigned int),
37 		.mode		= 0644,
38 		.proc_handler	= proc_douintvec_minmax,
39 		.extra1		= SYSCTL_ZERO,
40 		.extra2		= SYSCTL_TWO,
41 	},
42 	{
43 		.procname	= "smcr_testlink_time",
44 		.data		= &init_net.smc.sysctl_smcr_testlink_time,
45 		.maxlen		= sizeof(int),
46 		.mode		= 0644,
47 		.proc_handler	= proc_dointvec_jiffies,
48 	},
49 	{
50 		.procname	= "wmem",
51 		.data		= &init_net.smc.sysctl_wmem,
52 		.maxlen		= sizeof(int),
53 		.mode		= 0644,
54 		.proc_handler	= proc_dointvec_minmax,
55 		.extra1		= &min_sndbuf,
56 	},
57 	{
58 		.procname	= "rmem",
59 		.data		= &init_net.smc.sysctl_rmem,
60 		.maxlen		= sizeof(int),
61 		.mode		= 0644,
62 		.proc_handler	= proc_dointvec_minmax,
63 		.extra1		= &min_rcvbuf,
64 	},
65 	{  }
66 };
67 
68 int __net_init smc_sysctl_net_init(struct net *net)
69 {
70 	struct ctl_table *table;
71 
72 	table = smc_table;
73 	if (!net_eq(net, &init_net)) {
74 		int i;
75 
76 		table = kmemdup(table, sizeof(smc_table), GFP_KERNEL);
77 		if (!table)
78 			goto err_alloc;
79 
80 		for (i = 0; i < ARRAY_SIZE(smc_table) - 1; i++)
81 			table[i].data += (void *)net - (void *)&init_net;
82 	}
83 
84 	net->smc.smc_hdr = register_net_sysctl(net, "net/smc", table);
85 	if (!net->smc.smc_hdr)
86 		goto err_reg;
87 
88 	net->smc.sysctl_autocorking_size = SMC_AUTOCORKING_DEFAULT_SIZE;
89 	net->smc.sysctl_smcr_buf_type = SMCR_PHYS_CONT_BUFS;
90 	net->smc.sysctl_smcr_testlink_time = SMC_LLC_TESTLINK_DEFAULT_TIME;
91 	WRITE_ONCE(net->smc.sysctl_wmem, READ_ONCE(net->ipv4.sysctl_tcp_wmem[1]));
92 	WRITE_ONCE(net->smc.sysctl_rmem, READ_ONCE(net->ipv4.sysctl_tcp_rmem[1]));
93 
94 	return 0;
95 
96 err_reg:
97 	if (!net_eq(net, &init_net))
98 		kfree(table);
99 err_alloc:
100 	return -ENOMEM;
101 }
102 
103 void __net_exit smc_sysctl_net_exit(struct net *net)
104 {
105 	struct ctl_table *table;
106 
107 	table = net->smc.smc_hdr->ctl_table_arg;
108 	unregister_net_sysctl_table(net->smc.smc_hdr);
109 	if (!net_eq(net, &init_net))
110 		kfree(table);
111 }
112