1 /* -*- mode: c; c-basic-offset: 8; -*- 2 * vim: noexpandtab sw=8 ts=8 sts=0: 3 * 4 * stack_o2cb.c 5 * 6 * Code which interfaces ocfs2 with the o2cb stack. 7 * 8 * Copyright (C) 2007 Oracle. All rights reserved. 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public 12 * License as published by the Free Software Foundation, version 2. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 */ 19 20 #include <linux/kernel.h> 21 #include <linux/crc32.h> 22 #include <linux/module.h> 23 24 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */ 25 #include <linux/fs.h> 26 27 #include "cluster/masklog.h" 28 #include "cluster/nodemanager.h" 29 #include "cluster/heartbeat.h" 30 31 #include "stackglue.h" 32 33 struct o2dlm_private { 34 struct dlm_eviction_cb op_eviction_cb; 35 }; 36 37 static struct ocfs2_stack_plugin o2cb_stack; 38 39 /* These should be identical */ 40 #if (DLM_LOCK_IV != LKM_IVMODE) 41 # error Lock modes do not match 42 #endif 43 #if (DLM_LOCK_NL != LKM_NLMODE) 44 # error Lock modes do not match 45 #endif 46 #if (DLM_LOCK_CR != LKM_CRMODE) 47 # error Lock modes do not match 48 #endif 49 #if (DLM_LOCK_CW != LKM_CWMODE) 50 # error Lock modes do not match 51 #endif 52 #if (DLM_LOCK_PR != LKM_PRMODE) 53 # error Lock modes do not match 54 #endif 55 #if (DLM_LOCK_PW != LKM_PWMODE) 56 # error Lock modes do not match 57 #endif 58 #if (DLM_LOCK_EX != LKM_EXMODE) 59 # error Lock modes do not match 60 #endif 61 static inline int mode_to_o2dlm(int mode) 62 { 63 BUG_ON(mode > LKM_MAXMODE); 64 65 return mode; 66 } 67 68 #define map_flag(_generic, _o2dlm) \ 69 if (flags & (_generic)) { \ 70 flags &= ~(_generic); \ 71 o2dlm_flags |= (_o2dlm); \ 72 } 73 static int flags_to_o2dlm(u32 flags) 74 { 75 int o2dlm_flags = 0; 76 77 map_flag(DLM_LKF_NOQUEUE, LKM_NOQUEUE); 78 map_flag(DLM_LKF_CANCEL, LKM_CANCEL); 79 map_flag(DLM_LKF_CONVERT, LKM_CONVERT); 80 map_flag(DLM_LKF_VALBLK, LKM_VALBLK); 81 map_flag(DLM_LKF_IVVALBLK, LKM_INVVALBLK); 82 map_flag(DLM_LKF_ORPHAN, LKM_ORPHAN); 83 map_flag(DLM_LKF_FORCEUNLOCK, LKM_FORCE); 84 map_flag(DLM_LKF_TIMEOUT, LKM_TIMEOUT); 85 map_flag(DLM_LKF_LOCAL, LKM_LOCAL); 86 87 /* map_flag() should have cleared every flag passed in */ 88 BUG_ON(flags != 0); 89 90 return o2dlm_flags; 91 } 92 #undef map_flag 93 94 /* 95 * Map an o2dlm status to standard errno values. 96 * 97 * o2dlm only uses a handful of these, and returns even fewer to the 98 * caller. Still, we try to assign sane values to each error. 99 * 100 * The following value pairs have special meanings to dlmglue, thus 101 * the right hand side needs to stay unique - never duplicate the 102 * mapping elsewhere in the table! 103 * 104 * DLM_NORMAL: 0 105 * DLM_NOTQUEUED: -EAGAIN 106 * DLM_CANCELGRANT: -EBUSY 107 * DLM_CANCEL: -DLM_ECANCEL 108 */ 109 /* Keep in sync with dlmapi.h */ 110 static int status_map[] = { 111 [DLM_NORMAL] = 0, /* Success */ 112 [DLM_GRANTED] = -EINVAL, 113 [DLM_DENIED] = -EACCES, 114 [DLM_DENIED_NOLOCKS] = -EACCES, 115 [DLM_WORKING] = -EACCES, 116 [DLM_BLOCKED] = -EINVAL, 117 [DLM_BLOCKED_ORPHAN] = -EINVAL, 118 [DLM_DENIED_GRACE_PERIOD] = -EACCES, 119 [DLM_SYSERR] = -ENOMEM, /* It is what it is */ 120 [DLM_NOSUPPORT] = -EPROTO, 121 [DLM_CANCELGRANT] = -EBUSY, /* Cancel after grant */ 122 [DLM_IVLOCKID] = -EINVAL, 123 [DLM_SYNC] = -EINVAL, 124 [DLM_BADTYPE] = -EINVAL, 125 [DLM_BADRESOURCE] = -EINVAL, 126 [DLM_MAXHANDLES] = -ENOMEM, 127 [DLM_NOCLINFO] = -EINVAL, 128 [DLM_NOLOCKMGR] = -EINVAL, 129 [DLM_NOPURGED] = -EINVAL, 130 [DLM_BADARGS] = -EINVAL, 131 [DLM_VOID] = -EINVAL, 132 [DLM_NOTQUEUED] = -EAGAIN, /* Trylock failed */ 133 [DLM_IVBUFLEN] = -EINVAL, 134 [DLM_CVTUNGRANT] = -EPERM, 135 [DLM_BADPARAM] = -EINVAL, 136 [DLM_VALNOTVALID] = -EINVAL, 137 [DLM_REJECTED] = -EPERM, 138 [DLM_ABORT] = -EINVAL, 139 [DLM_CANCEL] = -DLM_ECANCEL, /* Successful cancel */ 140 [DLM_IVRESHANDLE] = -EINVAL, 141 [DLM_DEADLOCK] = -EDEADLK, 142 [DLM_DENIED_NOASTS] = -EINVAL, 143 [DLM_FORWARD] = -EINVAL, 144 [DLM_TIMEOUT] = -ETIMEDOUT, 145 [DLM_IVGROUPID] = -EINVAL, 146 [DLM_VERS_CONFLICT] = -EOPNOTSUPP, 147 [DLM_BAD_DEVICE_PATH] = -ENOENT, 148 [DLM_NO_DEVICE_PERMISSION] = -EPERM, 149 [DLM_NO_CONTROL_DEVICE] = -ENOENT, 150 [DLM_RECOVERING] = -ENOTCONN, 151 [DLM_MIGRATING] = -ERESTART, 152 [DLM_MAXSTATS] = -EINVAL, 153 }; 154 155 static int dlm_status_to_errno(enum dlm_status status) 156 { 157 BUG_ON(status < 0 || status >= ARRAY_SIZE(status_map)); 158 159 return status_map[status]; 160 } 161 162 static void o2dlm_lock_ast_wrapper(void *astarg) 163 { 164 BUG_ON(o2cb_stack.sp_proto == NULL); 165 166 o2cb_stack.sp_proto->lp_lock_ast(astarg); 167 } 168 169 static void o2dlm_blocking_ast_wrapper(void *astarg, int level) 170 { 171 BUG_ON(o2cb_stack.sp_proto == NULL); 172 173 o2cb_stack.sp_proto->lp_blocking_ast(astarg, level); 174 } 175 176 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status) 177 { 178 int error = dlm_status_to_errno(status); 179 180 BUG_ON(o2cb_stack.sp_proto == NULL); 181 182 /* 183 * In o2dlm, you can get both the lock_ast() for the lock being 184 * granted and the unlock_ast() for the CANCEL failing. A 185 * successful cancel sends DLM_NORMAL here. If the 186 * lock grant happened before the cancel arrived, you get 187 * DLM_CANCELGRANT. 188 * 189 * There's no need for the double-ast. If we see DLM_CANCELGRANT, 190 * we just ignore it. We expect the lock_ast() to handle the 191 * granted lock. 192 */ 193 if (status == DLM_CANCELGRANT) 194 return; 195 196 o2cb_stack.sp_proto->lp_unlock_ast(astarg, error); 197 } 198 199 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn, 200 int mode, 201 union ocfs2_dlm_lksb *lksb, 202 u32 flags, 203 void *name, 204 unsigned int namelen, 205 void *astarg) 206 { 207 enum dlm_status status; 208 int o2dlm_mode = mode_to_o2dlm(mode); 209 int o2dlm_flags = flags_to_o2dlm(flags); 210 int ret; 211 212 status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm, 213 o2dlm_flags, name, namelen, 214 o2dlm_lock_ast_wrapper, astarg, 215 o2dlm_blocking_ast_wrapper); 216 ret = dlm_status_to_errno(status); 217 return ret; 218 } 219 220 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn, 221 union ocfs2_dlm_lksb *lksb, 222 u32 flags, 223 void *astarg) 224 { 225 enum dlm_status status; 226 int o2dlm_flags = flags_to_o2dlm(flags); 227 int ret; 228 229 status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm, 230 o2dlm_flags, o2dlm_unlock_ast_wrapper, astarg); 231 ret = dlm_status_to_errno(status); 232 return ret; 233 } 234 235 static int o2cb_dlm_lock_status(union ocfs2_dlm_lksb *lksb) 236 { 237 return dlm_status_to_errno(lksb->lksb_o2dlm.status); 238 } 239 240 /* 241 * o2dlm aways has a "valid" LVB. If the dlm loses track of the LVB 242 * contents, it will zero out the LVB. Thus the caller can always trust 243 * the contents. 244 */ 245 static int o2cb_dlm_lvb_valid(union ocfs2_dlm_lksb *lksb) 246 { 247 return 1; 248 } 249 250 static void *o2cb_dlm_lvb(union ocfs2_dlm_lksb *lksb) 251 { 252 return (void *)(lksb->lksb_o2dlm.lvb); 253 } 254 255 static void o2cb_dump_lksb(union ocfs2_dlm_lksb *lksb) 256 { 257 dlm_print_one_lock(lksb->lksb_o2dlm.lockid); 258 } 259 260 /* 261 * Called from the dlm when it's about to evict a node. This is how the 262 * classic stack signals node death. 263 */ 264 static void o2dlm_eviction_cb(int node_num, void *data) 265 { 266 struct ocfs2_cluster_connection *conn = data; 267 268 mlog(ML_NOTICE, "o2dlm has evicted node %d from group %.*s\n", 269 node_num, conn->cc_namelen, conn->cc_name); 270 271 conn->cc_recovery_handler(node_num, conn->cc_recovery_data); 272 } 273 274 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn) 275 { 276 int rc = 0; 277 u32 dlm_key; 278 struct dlm_ctxt *dlm; 279 struct o2dlm_private *priv; 280 struct dlm_protocol_version dlm_version; 281 282 BUG_ON(conn == NULL); 283 BUG_ON(o2cb_stack.sp_proto == NULL); 284 285 /* for now we only have one cluster/node, make sure we see it 286 * in the heartbeat universe */ 287 if (!o2hb_check_local_node_heartbeating()) { 288 rc = -EINVAL; 289 goto out; 290 } 291 292 priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL); 293 if (!priv) { 294 rc = -ENOMEM; 295 goto out_free; 296 } 297 298 /* This just fills the structure in. It is safe to pass conn. */ 299 dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb, 300 conn); 301 302 conn->cc_private = priv; 303 304 /* used by the dlm code to make message headers unique, each 305 * node in this domain must agree on this. */ 306 dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen); 307 dlm_version.pv_major = conn->cc_version.pv_major; 308 dlm_version.pv_minor = conn->cc_version.pv_minor; 309 310 dlm = dlm_register_domain(conn->cc_name, dlm_key, &dlm_version); 311 if (IS_ERR(dlm)) { 312 rc = PTR_ERR(dlm); 313 mlog_errno(rc); 314 goto out_free; 315 } 316 317 conn->cc_version.pv_major = dlm_version.pv_major; 318 conn->cc_version.pv_minor = dlm_version.pv_minor; 319 conn->cc_lockspace = dlm; 320 321 dlm_register_eviction_cb(dlm, &priv->op_eviction_cb); 322 323 out_free: 324 if (rc && conn->cc_private) 325 kfree(conn->cc_private); 326 327 out: 328 return rc; 329 } 330 331 static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn) 332 { 333 struct dlm_ctxt *dlm = conn->cc_lockspace; 334 struct o2dlm_private *priv = conn->cc_private; 335 336 dlm_unregister_eviction_cb(&priv->op_eviction_cb); 337 conn->cc_private = NULL; 338 kfree(priv); 339 340 dlm_unregister_domain(dlm); 341 conn->cc_lockspace = NULL; 342 343 return 0; 344 } 345 346 static int o2cb_cluster_this_node(unsigned int *node) 347 { 348 int node_num; 349 350 node_num = o2nm_this_node(); 351 if (node_num == O2NM_INVALID_NODE_NUM) 352 return -ENOENT; 353 354 if (node_num >= O2NM_MAX_NODES) 355 return -EOVERFLOW; 356 357 *node = node_num; 358 return 0; 359 } 360 361 static struct ocfs2_stack_operations o2cb_stack_ops = { 362 .connect = o2cb_cluster_connect, 363 .disconnect = o2cb_cluster_disconnect, 364 .this_node = o2cb_cluster_this_node, 365 .dlm_lock = o2cb_dlm_lock, 366 .dlm_unlock = o2cb_dlm_unlock, 367 .lock_status = o2cb_dlm_lock_status, 368 .lvb_valid = o2cb_dlm_lvb_valid, 369 .lock_lvb = o2cb_dlm_lvb, 370 .dump_lksb = o2cb_dump_lksb, 371 }; 372 373 static struct ocfs2_stack_plugin o2cb_stack = { 374 .sp_name = "o2cb", 375 .sp_ops = &o2cb_stack_ops, 376 .sp_owner = THIS_MODULE, 377 }; 378 379 static int __init o2cb_stack_init(void) 380 { 381 return ocfs2_stack_glue_register(&o2cb_stack); 382 } 383 384 static void __exit o2cb_stack_exit(void) 385 { 386 ocfs2_stack_glue_unregister(&o2cb_stack); 387 } 388 389 MODULE_AUTHOR("Oracle"); 390 MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack"); 391 MODULE_LICENSE("GPL"); 392 module_init(o2cb_stack_init); 393 module_exit(o2cb_stack_exit); 394