drivers/staging/lustre/lnet/lnet/module.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2012, 2015, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_LNET
  38 #include "../../include/linux/lnet/lib-lnet.h"
  39
  40 static int config_on_load;
  41 module_param(config_on_load, int, 0444);
  42 MODULE_PARM_DESC(config_on_load, "configure network at module load");
  43
  44 static struct mutex lnet_config_mutex;
  45
  46 static int
  47 lnet_configure(void *arg)
  48 {
  49         /* 'arg' only there so I can be passed to cfs_create_thread() */
  50         int rc = 0;
  51
  52         mutex_lock(&lnet_config_mutex);
  53
  54         if (!the_lnet.ln_niinit_self) {
  55                 rc = LNetNIInit(LUSTRE_SRV_LNET_PID);
  56                 if (rc >= 0) {
  57                         the_lnet.ln_niinit_self = 1;
  58                         rc = 0;
  59                 }
  60         }
  61
  62         mutex_unlock(&lnet_config_mutex);
  63         return rc;
  64 }
  65
  66 static int
  67 lnet_unconfigure(void)
  68 {
  69         int refcount;
  70
  71         mutex_lock(&lnet_config_mutex);
  72
  73         if (the_lnet.ln_niinit_self) {
  74                 the_lnet.ln_niinit_self = 0;
  75                 LNetNIFini();
  76         }
  77
  78         mutex_lock(&the_lnet.ln_api_mutex);
  79         refcount = the_lnet.ln_refcount;
  80         mutex_unlock(&the_lnet.ln_api_mutex);
  81
  82         mutex_unlock(&lnet_config_mutex);
  83         return !refcount ? 0 : -EBUSY;
  84 }
  85
  86 static int
  87 lnet_ioctl(unsigned int cmd, struct libcfs_ioctl_hdr *hdr)
  88 {
  89         int rc;
  90
  91         switch (cmd) {
  92         case IOC_LIBCFS_CONFIGURE:
  93                 return lnet_configure(NULL);
  94
  95         case IOC_LIBCFS_UNCONFIGURE:
  96                 return lnet_unconfigure();
  97
  98         default:
  99                 /*
 100                  * Passing LNET_PID_ANY only gives me a ref if the net is up
 101                  * already; I'll need it to ensure the net can't go down while
 102                  * I'm called into it
 103                  */
 104                 rc = LNetNIInit(LNET_PID_ANY);
 105                 if (rc >= 0) {
 106                         rc = LNetCtl(cmd, hdr);
 107                         LNetNIFini();
 108                 }
 109                 return rc;
 110         }
 111 }
 112
 113 static DECLARE_IOCTL_HANDLER(lnet_ioctl_handler, lnet_ioctl);
 114
 115 static int __init
 116 init_lnet(void)
 117 {
 118         int rc;
 119
 120         mutex_init(&lnet_config_mutex);
 121
 122         rc = lnet_init();
 123         if (rc) {
 124                 CERROR("lnet_init: error %d\n", rc);
 125                 return rc;
 126         }
 127
 128         rc = libcfs_register_ioctl(&lnet_ioctl_handler);
 129         LASSERT(!rc);
 130
 131         if (config_on_load) {
 132                 /*
 133                  * Have to schedule a separate thread to avoid deadlocking
 134                  * in modload
 135                  */
 136                 (void) kthread_run(lnet_configure, NULL, "lnet_initd");
 137         }
 138
 139         return 0;
 140 }
 141
 142 static void __exit
 143 fini_lnet(void)
 144 {
 145         int rc;
 146
 147         rc = libcfs_deregister_ioctl(&lnet_ioctl_handler);
 148         LASSERT(!rc);
 149
 150         lnet_fini();
 151 }
 152
 153 MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>");
 154 MODULE_DESCRIPTION("LNet v3.1");
 155 MODULE_LICENSE("GPL");
 156 MODULE_VERSION("1.0.0");
 157
 158 module_init(init_lnet);
 159 module_exit(fini_lnet);