Joel Becker | 24ef181 | 2008-01-29 17:37:32 -0800 | [diff] [blame] | 1 | /* -*- mode: c; c-basic-offset: 8; -*- |
| 2 | * vim: noexpandtab sw=8 ts=8 sts=0: |
| 3 | * |
| 4 | * stackglue.c |
| 5 | * |
| 6 | * Code which implements an OCFS2 specific interface to underlying |
| 7 | * cluster stacks. |
| 8 | * |
| 9 | * Copyright (C) 2007 Oracle. All rights reserved. |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU General Public |
| 13 | * License as published by the Free Software Foundation, version 2. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * General Public License for more details. |
| 19 | */ |
| 20 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 21 | #include <linux/list.h> |
| 22 | #include <linux/spinlock.h> |
| 23 | #include <linux/module.h> |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 24 | #include <linux/slab.h> |
Joel Becker | 6953b4c | 2008-01-29 16:59:56 -0800 | [diff] [blame] | 25 | #include <linux/kmod.h> |
Joel Becker | 74ae4e1 | 2008-01-31 23:56:17 -0800 | [diff] [blame^] | 26 | #include <linux/fs.h> |
| 27 | #include <linux/kobject.h> |
| 28 | #include <linux/sysfs.h> |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 29 | |
Joel Becker | 24ef181 | 2008-01-29 17:37:32 -0800 | [diff] [blame] | 30 | #include "stackglue.h" |
| 31 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 32 | static struct ocfs2_locking_protocol *lproto; |
| 33 | static DEFINE_SPINLOCK(ocfs2_stack_lock); |
| 34 | static LIST_HEAD(ocfs2_stack_list); |
| 35 | |
| 36 | /* |
| 37 | * The stack currently in use. If not null, active_stack->sp_count > 0, |
| 38 | * the module is pinned, and the locking protocol cannot be changed. |
| 39 | */ |
| 40 | static struct ocfs2_stack_plugin *active_stack; |
| 41 | |
| 42 | static struct ocfs2_stack_plugin *ocfs2_stack_lookup(const char *name) |
| 43 | { |
| 44 | struct ocfs2_stack_plugin *p; |
| 45 | |
| 46 | assert_spin_locked(&ocfs2_stack_lock); |
| 47 | |
| 48 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { |
| 49 | if (!strcmp(p->sp_name, name)) |
| 50 | return p; |
| 51 | } |
| 52 | |
| 53 | return NULL; |
| 54 | } |
| 55 | |
| 56 | static int ocfs2_stack_driver_request(const char *name) |
| 57 | { |
| 58 | int rc; |
| 59 | struct ocfs2_stack_plugin *p; |
| 60 | |
| 61 | spin_lock(&ocfs2_stack_lock); |
| 62 | |
| 63 | if (active_stack) { |
| 64 | /* |
| 65 | * If the active stack isn't the one we want, it cannot |
| 66 | * be selected right now. |
| 67 | */ |
| 68 | if (!strcmp(active_stack->sp_name, name)) |
| 69 | rc = 0; |
| 70 | else |
| 71 | rc = -EBUSY; |
| 72 | goto out; |
| 73 | } |
| 74 | |
| 75 | p = ocfs2_stack_lookup(name); |
| 76 | if (!p || !try_module_get(p->sp_owner)) { |
| 77 | rc = -ENOENT; |
| 78 | goto out; |
| 79 | } |
| 80 | |
| 81 | /* Ok, the stack is pinned */ |
| 82 | p->sp_count++; |
| 83 | active_stack = p; |
| 84 | |
| 85 | rc = 0; |
| 86 | |
| 87 | out: |
| 88 | spin_unlock(&ocfs2_stack_lock); |
| 89 | return rc; |
| 90 | } |
| 91 | |
| 92 | /* |
| 93 | * This function looks up the appropriate stack and makes it active. If |
| 94 | * there is no stack, it tries to load it. It will fail if the stack still |
| 95 | * cannot be found. It will also fail if a different stack is in use. |
| 96 | */ |
| 97 | static int ocfs2_stack_driver_get(const char *name) |
| 98 | { |
| 99 | int rc; |
| 100 | |
| 101 | rc = ocfs2_stack_driver_request(name); |
| 102 | if (rc == -ENOENT) { |
| 103 | request_module("ocfs2_stack_%s", name); |
| 104 | rc = ocfs2_stack_driver_request(name); |
| 105 | } |
| 106 | |
| 107 | if (rc == -ENOENT) { |
| 108 | printk(KERN_ERR |
| 109 | "ocfs2: Cluster stack driver \"%s\" cannot be found\n", |
| 110 | name); |
| 111 | } else if (rc == -EBUSY) { |
| 112 | printk(KERN_ERR |
| 113 | "ocfs2: A different cluster stack driver is in use\n"); |
| 114 | } |
| 115 | |
| 116 | return rc; |
| 117 | } |
| 118 | |
| 119 | static void ocfs2_stack_driver_put(void) |
| 120 | { |
| 121 | spin_lock(&ocfs2_stack_lock); |
| 122 | BUG_ON(active_stack == NULL); |
| 123 | BUG_ON(active_stack->sp_count == 0); |
| 124 | |
| 125 | active_stack->sp_count--; |
| 126 | if (!active_stack->sp_count) { |
| 127 | module_put(active_stack->sp_owner); |
| 128 | active_stack = NULL; |
| 129 | } |
| 130 | spin_unlock(&ocfs2_stack_lock); |
| 131 | } |
| 132 | |
| 133 | int ocfs2_stack_glue_register(struct ocfs2_stack_plugin *plugin) |
| 134 | { |
| 135 | int rc; |
| 136 | |
| 137 | spin_lock(&ocfs2_stack_lock); |
| 138 | if (!ocfs2_stack_lookup(plugin->sp_name)) { |
| 139 | plugin->sp_count = 0; |
| 140 | plugin->sp_proto = lproto; |
| 141 | list_add(&plugin->sp_list, &ocfs2_stack_list); |
| 142 | printk(KERN_INFO "ocfs2: Registered cluster interface %s\n", |
| 143 | plugin->sp_name); |
| 144 | rc = 0; |
| 145 | } else { |
| 146 | printk(KERN_ERR "ocfs2: Stack \"%s\" already registered\n", |
| 147 | plugin->sp_name); |
| 148 | rc = -EEXIST; |
| 149 | } |
| 150 | spin_unlock(&ocfs2_stack_lock); |
| 151 | |
| 152 | return rc; |
| 153 | } |
| 154 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_register); |
| 155 | |
| 156 | void ocfs2_stack_glue_unregister(struct ocfs2_stack_plugin *plugin) |
| 157 | { |
| 158 | struct ocfs2_stack_plugin *p; |
| 159 | |
| 160 | spin_lock(&ocfs2_stack_lock); |
| 161 | p = ocfs2_stack_lookup(plugin->sp_name); |
| 162 | if (p) { |
| 163 | BUG_ON(p != plugin); |
| 164 | BUG_ON(plugin == active_stack); |
| 165 | BUG_ON(plugin->sp_count != 0); |
| 166 | list_del_init(&plugin->sp_list); |
| 167 | printk(KERN_INFO "ocfs2: Unregistered cluster interface %s\n", |
| 168 | plugin->sp_name); |
| 169 | } else { |
| 170 | printk(KERN_ERR "Stack \"%s\" is not registered\n", |
| 171 | plugin->sp_name); |
| 172 | } |
| 173 | spin_unlock(&ocfs2_stack_lock); |
| 174 | } |
| 175 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_unregister); |
| 176 | |
| 177 | void ocfs2_stack_glue_set_locking_protocol(struct ocfs2_locking_protocol *proto) |
| 178 | { |
| 179 | struct ocfs2_stack_plugin *p; |
| 180 | |
| 181 | BUG_ON(proto == NULL); |
| 182 | |
| 183 | spin_lock(&ocfs2_stack_lock); |
| 184 | BUG_ON(active_stack != NULL); |
| 185 | |
| 186 | lproto = proto; |
| 187 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { |
| 188 | p->sp_proto = lproto; |
| 189 | } |
| 190 | |
| 191 | spin_unlock(&ocfs2_stack_lock); |
| 192 | } |
| 193 | EXPORT_SYMBOL_GPL(ocfs2_stack_glue_set_locking_protocol); |
Joel Becker | 24ef181 | 2008-01-29 17:37:32 -0800 | [diff] [blame] | 194 | |
Joel Becker | 24ef181 | 2008-01-29 17:37:32 -0800 | [diff] [blame] | 195 | |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 196 | int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn, |
| 197 | int mode, |
| 198 | union ocfs2_dlm_lksb *lksb, |
| 199 | u32 flags, |
| 200 | void *name, |
| 201 | unsigned int namelen, |
| 202 | void *astarg) |
| 203 | { |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 204 | BUG_ON(lproto == NULL); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 205 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 206 | return active_stack->sp_ops->dlm_lock(conn, mode, lksb, flags, |
| 207 | name, namelen, astarg); |
Joel Becker | 24ef181 | 2008-01-29 17:37:32 -0800 | [diff] [blame] | 208 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 209 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lock); |
Joel Becker | 24ef181 | 2008-01-29 17:37:32 -0800 | [diff] [blame] | 210 | |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 211 | int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn, |
| 212 | union ocfs2_dlm_lksb *lksb, |
| 213 | u32 flags, |
| 214 | void *astarg) |
| 215 | { |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 216 | BUG_ON(lproto == NULL); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 217 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 218 | return active_stack->sp_ops->dlm_unlock(conn, lksb, flags, astarg); |
Joel Becker | 8f2c9c1 | 2008-02-01 12:16:57 -0800 | [diff] [blame] | 219 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 220 | EXPORT_SYMBOL_GPL(ocfs2_dlm_unlock); |
Joel Becker | 8f2c9c1 | 2008-02-01 12:16:57 -0800 | [diff] [blame] | 221 | |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 222 | int ocfs2_dlm_lock_status(union ocfs2_dlm_lksb *lksb) |
| 223 | { |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 224 | return active_stack->sp_ops->lock_status(lksb); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 225 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 226 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lock_status); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 227 | |
Joel Becker | 8f2c9c1 | 2008-02-01 12:16:57 -0800 | [diff] [blame] | 228 | /* |
| 229 | * Why don't we cast to ocfs2_meta_lvb? The "clean" answer is that we |
| 230 | * don't cast at the glue level. The real answer is that the header |
| 231 | * ordering is nigh impossible. |
| 232 | */ |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 233 | void *ocfs2_dlm_lvb(union ocfs2_dlm_lksb *lksb) |
| 234 | { |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 235 | return active_stack->sp_ops->lock_lvb(lksb); |
Joel Becker | cf0acdc | 2008-01-29 16:59:55 -0800 | [diff] [blame] | 236 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 237 | EXPORT_SYMBOL_GPL(ocfs2_dlm_lvb); |
Joel Becker | cf0acdc | 2008-01-29 16:59:55 -0800 | [diff] [blame] | 238 | |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 239 | void ocfs2_dlm_dump_lksb(union ocfs2_dlm_lksb *lksb) |
| 240 | { |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 241 | active_stack->sp_ops->dump_lksb(lksb); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 242 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 243 | EXPORT_SYMBOL_GPL(ocfs2_dlm_dump_lksb); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 244 | |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 245 | int ocfs2_cluster_connect(const char *group, |
| 246 | int grouplen, |
| 247 | void (*recovery_handler)(int node_num, |
| 248 | void *recovery_data), |
| 249 | void *recovery_data, |
| 250 | struct ocfs2_cluster_connection **conn) |
| 251 | { |
| 252 | int rc = 0; |
| 253 | struct ocfs2_cluster_connection *new_conn; |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 254 | |
| 255 | BUG_ON(group == NULL); |
| 256 | BUG_ON(conn == NULL); |
| 257 | BUG_ON(recovery_handler == NULL); |
| 258 | |
| 259 | if (grouplen > GROUP_NAME_MAX) { |
| 260 | rc = -EINVAL; |
| 261 | goto out; |
| 262 | } |
| 263 | |
| 264 | new_conn = kzalloc(sizeof(struct ocfs2_cluster_connection), |
| 265 | GFP_KERNEL); |
| 266 | if (!new_conn) { |
| 267 | rc = -ENOMEM; |
| 268 | goto out; |
| 269 | } |
| 270 | |
| 271 | memcpy(new_conn->cc_name, group, grouplen); |
| 272 | new_conn->cc_namelen = grouplen; |
| 273 | new_conn->cc_recovery_handler = recovery_handler; |
| 274 | new_conn->cc_recovery_data = recovery_data; |
| 275 | |
| 276 | /* Start the new connection at our maximum compatibility level */ |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 277 | new_conn->cc_version = lproto->lp_max_version; |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 278 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 279 | /* This will pin the stack driver if successful */ |
| 280 | rc = ocfs2_stack_driver_get("o2cb"); |
| 281 | if (rc) |
| 282 | goto out_free; |
| 283 | |
| 284 | rc = active_stack->sp_ops->connect(new_conn); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 285 | if (rc) { |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 286 | ocfs2_stack_driver_put(); |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 287 | goto out_free; |
| 288 | } |
| 289 | |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 290 | *conn = new_conn; |
| 291 | |
| 292 | out_free: |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 293 | if (rc) |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 294 | kfree(new_conn); |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 295 | |
| 296 | out: |
| 297 | return rc; |
| 298 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 299 | EXPORT_SYMBOL_GPL(ocfs2_cluster_connect); |
Joel Becker | 4670c46 | 2008-02-01 14:39:35 -0800 | [diff] [blame] | 300 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 301 | /* If hangup_pending is 0, the stack driver will be dropped */ |
| 302 | int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn, |
| 303 | int hangup_pending) |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 304 | { |
| 305 | int ret; |
| 306 | |
| 307 | BUG_ON(conn == NULL); |
| 308 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 309 | ret = active_stack->sp_ops->disconnect(conn, hangup_pending); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 310 | |
| 311 | /* XXX Should we free it anyway? */ |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 312 | if (!ret) { |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 313 | kfree(conn); |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 314 | if (!hangup_pending) |
| 315 | ocfs2_stack_driver_put(); |
| 316 | } |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 317 | |
| 318 | return ret; |
| 319 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 320 | EXPORT_SYMBOL_GPL(ocfs2_cluster_disconnect); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 321 | |
Joel Becker | 6953b4c | 2008-01-29 16:59:56 -0800 | [diff] [blame] | 322 | void ocfs2_cluster_hangup(const char *group, int grouplen) |
| 323 | { |
| 324 | BUG_ON(group == NULL); |
| 325 | BUG_ON(group[grouplen] != '\0'); |
| 326 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 327 | active_stack->sp_ops->hangup(group, grouplen); |
| 328 | |
| 329 | /* cluster_disconnect() was called with hangup_pending==1 */ |
| 330 | ocfs2_stack_driver_put(); |
Joel Becker | 19fdb62 | 2008-01-30 15:38:24 -0800 | [diff] [blame] | 331 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 332 | EXPORT_SYMBOL_GPL(ocfs2_cluster_hangup); |
Joel Becker | 19fdb62 | 2008-01-30 15:38:24 -0800 | [diff] [blame] | 333 | |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 334 | int ocfs2_cluster_this_node(unsigned int *node) |
| 335 | { |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 336 | return active_stack->sp_ops->this_node(node); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 337 | } |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 338 | EXPORT_SYMBOL_GPL(ocfs2_cluster_this_node); |
Joel Becker | 553aa7e | 2008-02-01 14:51:03 -0800 | [diff] [blame] | 339 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 340 | |
Joel Becker | 74ae4e1 | 2008-01-31 23:56:17 -0800 | [diff] [blame^] | 341 | /* |
| 342 | * Sysfs bits |
| 343 | */ |
| 344 | |
| 345 | static ssize_t ocfs2_max_locking_protocol_show(struct kobject *kobj, |
| 346 | struct kobj_attribute *attr, |
| 347 | char *buf) |
| 348 | { |
| 349 | ssize_t ret = 0; |
| 350 | |
| 351 | spin_lock(&ocfs2_stack_lock); |
| 352 | if (lproto) |
| 353 | ret = snprintf(buf, PAGE_SIZE, "%u.%u\n", |
| 354 | lproto->lp_max_version.pv_major, |
| 355 | lproto->lp_max_version.pv_minor); |
| 356 | spin_unlock(&ocfs2_stack_lock); |
| 357 | |
| 358 | return ret; |
| 359 | } |
| 360 | |
| 361 | static struct kobj_attribute ocfs2_attr_max_locking_protocol = |
| 362 | __ATTR(max_locking_protocol, S_IFREG | S_IRUGO, |
| 363 | ocfs2_max_locking_protocol_show, NULL); |
| 364 | |
| 365 | static ssize_t ocfs2_loaded_cluster_plugins_show(struct kobject *kobj, |
| 366 | struct kobj_attribute *attr, |
| 367 | char *buf) |
| 368 | { |
| 369 | ssize_t ret = 0, total = 0, remain = PAGE_SIZE; |
| 370 | struct ocfs2_stack_plugin *p; |
| 371 | |
| 372 | spin_lock(&ocfs2_stack_lock); |
| 373 | list_for_each_entry(p, &ocfs2_stack_list, sp_list) { |
| 374 | ret = snprintf(buf, remain, "%s\n", |
| 375 | p->sp_name); |
| 376 | if (ret < 0) { |
| 377 | total = ret; |
| 378 | break; |
| 379 | } |
| 380 | if (ret == remain) { |
| 381 | /* snprintf() didn't fit */ |
| 382 | total = -E2BIG; |
| 383 | break; |
| 384 | } |
| 385 | total += ret; |
| 386 | remain -= ret; |
| 387 | } |
| 388 | spin_unlock(&ocfs2_stack_lock); |
| 389 | |
| 390 | return total; |
| 391 | } |
| 392 | |
| 393 | static struct kobj_attribute ocfs2_attr_loaded_cluster_plugins = |
| 394 | __ATTR(loaded_cluster_plugins, S_IFREG | S_IRUGO, |
| 395 | ocfs2_loaded_cluster_plugins_show, NULL); |
| 396 | |
| 397 | static ssize_t ocfs2_active_cluster_plugin_show(struct kobject *kobj, |
| 398 | struct kobj_attribute *attr, |
| 399 | char *buf) |
| 400 | { |
| 401 | ssize_t ret = 0; |
| 402 | |
| 403 | spin_lock(&ocfs2_stack_lock); |
| 404 | if (active_stack) { |
| 405 | ret = snprintf(buf, PAGE_SIZE, "%s\n", |
| 406 | active_stack->sp_name); |
| 407 | if (ret == PAGE_SIZE) |
| 408 | ret = -E2BIG; |
| 409 | } |
| 410 | spin_unlock(&ocfs2_stack_lock); |
| 411 | |
| 412 | return ret; |
| 413 | } |
| 414 | |
| 415 | static struct kobj_attribute ocfs2_attr_active_cluster_plugin = |
| 416 | __ATTR(active_cluster_plugin, S_IFREG | S_IRUGO, |
| 417 | ocfs2_active_cluster_plugin_show, NULL); |
| 418 | |
| 419 | static struct attribute *ocfs2_attrs[] = { |
| 420 | &ocfs2_attr_max_locking_protocol.attr, |
| 421 | &ocfs2_attr_loaded_cluster_plugins.attr, |
| 422 | &ocfs2_attr_active_cluster_plugin.attr, |
| 423 | NULL, |
| 424 | }; |
| 425 | |
| 426 | static struct attribute_group ocfs2_attr_group = { |
| 427 | .attrs = ocfs2_attrs, |
| 428 | }; |
| 429 | |
| 430 | static struct kset *ocfs2_kset; |
| 431 | |
| 432 | static void ocfs2_sysfs_exit(void) |
| 433 | { |
| 434 | kset_unregister(ocfs2_kset); |
| 435 | } |
| 436 | |
| 437 | static int ocfs2_sysfs_init(void) |
| 438 | { |
| 439 | int ret; |
| 440 | |
| 441 | ocfs2_kset = kset_create_and_add("ocfs2", NULL, fs_kobj); |
| 442 | if (!ocfs2_kset) |
| 443 | return -ENOMEM; |
| 444 | |
| 445 | ret = sysfs_create_group(&ocfs2_kset->kobj, &ocfs2_attr_group); |
| 446 | if (ret) |
| 447 | goto error; |
| 448 | |
| 449 | return 0; |
| 450 | |
| 451 | error: |
| 452 | kset_unregister(ocfs2_kset); |
| 453 | return ret; |
| 454 | } |
| 455 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 456 | static int __init ocfs2_stack_glue_init(void) |
Joel Becker | 24ef181 | 2008-01-29 17:37:32 -0800 | [diff] [blame] | 457 | { |
Joel Becker | 74ae4e1 | 2008-01-31 23:56:17 -0800 | [diff] [blame^] | 458 | return ocfs2_sysfs_init(); |
Joel Becker | 24ef181 | 2008-01-29 17:37:32 -0800 | [diff] [blame] | 459 | } |
| 460 | |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 461 | static void __exit ocfs2_stack_glue_exit(void) |
| 462 | { |
| 463 | lproto = NULL; |
Joel Becker | 74ae4e1 | 2008-01-31 23:56:17 -0800 | [diff] [blame^] | 464 | ocfs2_sysfs_exit(); |
Joel Becker | 286eaa9 | 2008-02-01 15:03:57 -0800 | [diff] [blame] | 465 | } |
| 466 | |
| 467 | MODULE_AUTHOR("Oracle"); |
| 468 | MODULE_DESCRIPTION("ocfs2 cluter stack glue layer"); |
| 469 | MODULE_LICENSE("GPL"); |
| 470 | module_init(ocfs2_stack_glue_init); |
| 471 | module_exit(ocfs2_stack_glue_exit); |