4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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.
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).
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
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
27 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
28 * Use is subject to license terms.
30 * Copyright (c) 2012, Intel Corporation.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * Author: Nathan Rutman <nathan.rutman@sun.com>
38 * Kernel <-> userspace communication routines.
39 * Using pipes for all arches.
42 #define DEBUG_SUBSYSTEM S_CLASS
45 #include "../include/obd_support.h"
46 #include "../include/lustre_kernelcomm.h"
49 * libcfs_kkuc_msg_put - send an message from kernel to userspace
50 * @param fp to send the message to
51 * @param payload Payload data. First field of payload is always
54 int libcfs_kkuc_msg_put(struct file *filp, void *payload)
56 struct kuc_hdr *kuch = (struct kuc_hdr *)payload;
57 ssize_t count = kuch->kuc_msglen;
62 if (!filp || IS_ERR(filp))
65 if (kuch->kuc_magic != KUC_MAGIC) {
66 CERROR("KernelComm: bad magic %x\n", kuch->kuc_magic);
73 rc = vfs_write(filp, (void __force __user *)payload,
84 CWARN("message send failed (%d)\n", rc);
86 CDEBUG(D_KUC, "Sent message rc=%d, fp=%p\n", rc, filp);
90 EXPORT_SYMBOL(libcfs_kkuc_msg_put);
93 * Broadcast groups are global across all mounted filesystems;
94 * i.e. registering for a group on 1 fs will get messages for that
97 /** A single group registration has a uid and a file pointer */
99 struct list_head kr_chain;
105 static struct list_head kkuc_groups[KUC_GRP_MAX + 1] = {};
106 /* Protect message sending against remove and adds */
107 static DECLARE_RWSEM(kg_sem);
109 /** Add a receiver to a broadcast group
110 * @param filp pipe to write into
111 * @param uid identifier for this receiver
112 * @param group group number
113 * @param data user data
115 int libcfs_kkuc_group_add(struct file *filp, int uid, unsigned int group,
116 void *data, size_t data_len)
118 struct kkuc_reg *reg;
120 if (group > KUC_GRP_MAX) {
121 CDEBUG(D_WARNING, "Kernelcomm: bad group %d\n", group);
125 /* fput in group_rem */
129 /* freed in group_rem */
130 reg = kmalloc(sizeof(*reg) + data_len, 0);
136 memcpy(reg->kr_data, data, data_len);
139 if (!kkuc_groups[group].next)
140 INIT_LIST_HEAD(&kkuc_groups[group]);
141 list_add(®->kr_chain, &kkuc_groups[group]);
144 CDEBUG(D_KUC, "Added uid=%d fp=%p to group %d\n", uid, filp, group);
148 EXPORT_SYMBOL(libcfs_kkuc_group_add);
150 int libcfs_kkuc_group_rem(int uid, unsigned int group)
152 struct kkuc_reg *reg, *next;
154 if (!kkuc_groups[group].next)
158 /* Broadcast a shutdown message */
161 lh.kuc_magic = KUC_MAGIC;
162 lh.kuc_transport = KUC_TRANSPORT_GENERIC;
163 lh.kuc_msgtype = KUC_MSG_SHUTDOWN;
164 lh.kuc_msglen = sizeof(lh);
165 libcfs_kkuc_group_put(group, &lh);
169 list_for_each_entry_safe(reg, next, &kkuc_groups[group], kr_chain) {
170 if (!uid || (uid == reg->kr_uid)) {
171 list_del(®->kr_chain);
172 CDEBUG(D_KUC, "Removed uid=%d fp=%p from group %d\n",
173 reg->kr_uid, reg->kr_fp, group);
183 EXPORT_SYMBOL(libcfs_kkuc_group_rem);
185 int libcfs_kkuc_group_put(unsigned int group, void *payload)
187 struct kkuc_reg *reg;
192 list_for_each_entry(reg, &kkuc_groups[group], kr_chain) {
194 rc = libcfs_kkuc_msg_put(reg->kr_fp, payload);
197 } else if (rc == -EPIPE) {
206 * don't return an error if the message has been delivered
207 * at least to one agent
214 EXPORT_SYMBOL(libcfs_kkuc_group_put);
217 * Calls a callback function for each link of the given kuc group.
218 * @param group the group to call the function on.
219 * @param cb_func the function to be called.
220 * @param cb_arg extra argument to be passed to the callback function.
222 int libcfs_kkuc_group_foreach(unsigned int group, libcfs_kkuc_cb_t cb_func,
225 struct kkuc_reg *reg;
228 if (group > KUC_GRP_MAX) {
229 CDEBUG(D_WARNING, "Kernelcomm: bad group %d\n", group);
233 /* no link for this group */
234 if (!kkuc_groups[group].next)
238 list_for_each_entry(reg, &kkuc_groups[group], kr_chain) {
240 rc = cb_func(reg->kr_data, cb_arg);
246 EXPORT_SYMBOL(libcfs_kkuc_group_foreach);