net/smc/smc_sysctl.c

   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 <[email protected]>
  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 }