Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
at v4.18-rc4 140 lines 3.0 kB view raw
1/* 2 * Copyright (C) 2007 Red Hat, Inc. All rights reserved. 3 * 4 * This copyrighted material is made available to anyone wishing to use, 5 * modify, copy, or redistribute it subject to the terms and conditions 6 * of the GNU General Public License v.2. 7 */ 8 9#include <net/genetlink.h> 10#include <linux/dlm.h> 11#include <linux/dlm_netlink.h> 12#include <linux/gfp.h> 13 14#include "dlm_internal.h" 15 16static uint32_t dlm_nl_seqnum; 17static uint32_t listener_nlportid; 18 19static struct genl_family family; 20 21static int prepare_data(u8 cmd, struct sk_buff **skbp, size_t size) 22{ 23 struct sk_buff *skb; 24 void *data; 25 26 skb = genlmsg_new(size, GFP_NOFS); 27 if (!skb) 28 return -ENOMEM; 29 30 /* add the message headers */ 31 data = genlmsg_put(skb, 0, dlm_nl_seqnum++, &family, 0, cmd); 32 if (!data) { 33 nlmsg_free(skb); 34 return -EINVAL; 35 } 36 37 *skbp = skb; 38 return 0; 39} 40 41static struct dlm_lock_data *mk_data(struct sk_buff *skb) 42{ 43 struct nlattr *ret; 44 45 ret = nla_reserve(skb, DLM_TYPE_LOCK, sizeof(struct dlm_lock_data)); 46 if (!ret) 47 return NULL; 48 return nla_data(ret); 49} 50 51static int send_data(struct sk_buff *skb) 52{ 53 struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data); 54 void *data = genlmsg_data(genlhdr); 55 56 genlmsg_end(skb, data); 57 58 return genlmsg_unicast(&init_net, skb, listener_nlportid); 59} 60 61static int user_cmd(struct sk_buff *skb, struct genl_info *info) 62{ 63 listener_nlportid = info->snd_portid; 64 printk("user_cmd nlpid %u\n", listener_nlportid); 65 return 0; 66} 67 68static const struct genl_ops dlm_nl_ops[] = { 69 { 70 .cmd = DLM_CMD_HELLO, 71 .doit = user_cmd, 72 }, 73}; 74 75static struct genl_family family __ro_after_init = { 76 .name = DLM_GENL_NAME, 77 .version = DLM_GENL_VERSION, 78 .ops = dlm_nl_ops, 79 .n_ops = ARRAY_SIZE(dlm_nl_ops), 80 .module = THIS_MODULE, 81}; 82 83int __init dlm_netlink_init(void) 84{ 85 return genl_register_family(&family); 86} 87 88void dlm_netlink_exit(void) 89{ 90 genl_unregister_family(&family); 91} 92 93static void fill_data(struct dlm_lock_data *data, struct dlm_lkb *lkb) 94{ 95 struct dlm_rsb *r = lkb->lkb_resource; 96 97 memset(data, 0, sizeof(struct dlm_lock_data)); 98 99 data->version = DLM_LOCK_DATA_VERSION; 100 data->nodeid = lkb->lkb_nodeid; 101 data->ownpid = lkb->lkb_ownpid; 102 data->id = lkb->lkb_id; 103 data->remid = lkb->lkb_remid; 104 data->status = lkb->lkb_status; 105 data->grmode = lkb->lkb_grmode; 106 data->rqmode = lkb->lkb_rqmode; 107 if (lkb->lkb_ua) 108 data->xid = lkb->lkb_ua->xid; 109 if (r) { 110 data->lockspace_id = r->res_ls->ls_global_id; 111 data->resource_namelen = r->res_length; 112 memcpy(data->resource_name, r->res_name, r->res_length); 113 } 114} 115 116void dlm_timeout_warn(struct dlm_lkb *lkb) 117{ 118 struct sk_buff *uninitialized_var(send_skb); 119 struct dlm_lock_data *data; 120 size_t size; 121 int rv; 122 123 size = nla_total_size(sizeof(struct dlm_lock_data)) + 124 nla_total_size(0); /* why this? */ 125 126 rv = prepare_data(DLM_CMD_TIMEOUT, &send_skb, size); 127 if (rv < 0) 128 return; 129 130 data = mk_data(send_skb); 131 if (!data) { 132 nlmsg_free(send_skb); 133 return; 134 } 135 136 fill_data(data, lkb); 137 138 send_data(send_skb); 139} 140