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/slab.h> 23 #include <linux/module.h> 24 25 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */ 26 #include <linux/fs.h> 27 28 #include "cluster/masklog.h" 29 #include "cluster/nodemanager.h" 30 #include "cluster/heartbeat.h" 31 32 #include "stackglue.h" 33 34 struct o2dlm_private { 35 struct dlm_eviction_cb op_eviction_cb; 36 }; 37 38 static struct ocfs2_stack_plugin o2cb_stack; 39 40 /* These should be identical */ 41 #if (DLM_LOCK_IV != LKM_IVMODE) 42 # error Lock modes do not match 43 #endif 44 #if (DLM_LOCK_NL != LKM_NLMODE) 45 # error Lock modes do not match 46 #endif 47 #if (DLM_LOCK_CR != LKM_CRMODE) 48 # error Lock modes do not match 49 #endif 50 #if (DLM_LOCK_CW != LKM_CWMODE) 51 # error Lock modes do not match 52 #endif 53 #if (DLM_LOCK_PR != LKM_PRMODE) 54 # error Lock modes do not match 55 #endif 56 #if (DLM_LOCK_PW != LKM_PWMODE) 57 # error Lock modes do not match 58 #endif 59 #if (DLM_LOCK_EX != LKM_EXMODE) 60 # error Lock modes do not match 61 #endif 62 static inline int mode_to_o2dlm(int mode) 63 { 64 BUG_ON(mode > LKM_MAXMODE); 65 66 return mode; 67 } 68 69 #define map_flag(_generic, _o2dlm) \ 70 if (flags & (_generic)) { \ 71 flags &= ~(_generic); \ 72 o2dlm_flags |= (_o2dlm); \ 73 } 74 static int flags_to_o2dlm(u32 flags) 75 { 76 int o2dlm_flags = 0; 77 78 map_flag(DLM_LKF_NOQUEUE, LKM_NOQUEUE); 79 map_flag(DLM_LKF_CANCEL, LKM_CANCEL); 80 map_flag(DLM_LKF_CONVERT, LKM_CONVERT); 81 map_flag(DLM_LKF_VALBLK, LKM_VALBLK); 82 map_flag(DLM_LKF_IVVALBLK, LKM_INVVALBLK); 83 map_flag(DLM_LKF_ORPHAN, LKM_ORPHAN); 84 map_flag(DLM_LKF_FORCEUNLOCK, LKM_FORCE); 85 map_flag(DLM_LKF_TIMEOUT, LKM_TIMEOUT); 86 map_flag(DLM_LKF_LOCAL, LKM_LOCAL); 87 88 /* map_flag() should have cleared every flag passed in */ 89 BUG_ON(flags != 0); 90 91 return o2dlm_flags; 92 } 93 #undef map_flag 94 95 /* 96 * Map an o2dlm status to standard errno values. 97 * 98 * o2dlm only uses a handful of these, and returns even fewer to the 99 * caller. Still, we try to assign sane values to each error. 100 * 101 * The following value pairs have special meanings to dlmglue, thus 102 * the right hand side needs to stay unique - never duplicate the 103 * mapping elsewhere in the table! 104 * 105 * DLM_NORMAL: 0 106 * DLM_NOTQUEUED: -EAGAIN 107 * DLM_CANCELGRANT: -EBUSY 108 * DLM_CANCEL: -DLM_ECANCEL 109 */ 110 /* Keep in sync with dlmapi.h */ 111 static int status_map[] = { 112 [DLM_NORMAL] = 0, /* Success */ 113 [DLM_GRANTED] = -EINVAL, 114 [DLM_DENIED] = -EACCES, 115 [DLM_DENIED_NOLOCKS] = -EACCES, 116 [DLM_WORKING] = -EACCES, 117 [DLM_BLOCKED] = -EINVAL, 118 [DLM_BLOCKED_ORPHAN] = -EINVAL, 119 [DLM_DENIED_GRACE_PERIOD] = -EACCES, 120 [DLM_SYSERR] = -ENOMEM, /* It is what it is */ 121 [DLM_NOSUPPORT] = -EPROTO, 122 [DLM_CANCELGRANT] = -EBUSY, /* Cancel after grant */ 123 [DLM_IVLOCKID] = -EINVAL, 124 [DLM_SYNC] = -EINVAL, 125 [DLM_BADTYPE] = -EINVAL, 126 [DLM_BADRESOURCE] = -EINVAL, 127 [DLM_MAXHANDLES] = -ENOMEM, 128 [DLM_NOCLINFO] = -EINVAL, 129 [DLM_NOLOCKMGR] = -EINVAL, 130 [DLM_NOPURGED] = -EINVAL, 131 [DLM_BADARGS] = -EINVAL, 132 [DLM_VOID] = -EINVAL, 133 [DLM_NOTQUEUED] = -EAGAIN, /* Trylock failed */ 134 [DLM_IVBUFLEN] = -EINVAL, 135 [DLM_CVTUNGRANT] = -EPERM, 136 [DLM_BADPARAM] = -EINVAL, 137 [DLM_VALNOTVALID] = -EINVAL, 138 [DLM_REJECTED] = -EPERM, 139 [DLM_ABORT] = -EINVAL, 140 [DLM_CANCEL] = -DLM_ECANCEL, /* Successful cancel */ 141 [DLM_IVRESHANDLE] = -EINVAL, 142 [DLM_DEADLOCK] = -EDEADLK, 143 [DLM_DENIED_NOASTS] = -EINVAL, 144 [DLM_FORWARD] = -EINVAL, 145 [DLM_TIMEOUT] = -ETIMEDOUT, 146 [DLM_IVGROUPID] = -EINVAL, 147 [DLM_VERS_CONFLICT] = -EOPNOTSUPP, 148 [DLM_BAD_DEVICE_PATH] = -ENOENT, 149 [DLM_NO_DEVICE_PERMISSION] = -EPERM, 150 [DLM_NO_CONTROL_DEVICE] = -ENOENT, 151 [DLM_RECOVERING] = -ENOTCONN, 152 [DLM_MIGRATING] = -ERESTART, 153 [DLM_MAXSTATS] = -EINVAL, 154 }; 155 156 static int dlm_status_to_errno(enum dlm_status status) 157 { 158 BUG_ON(status < 0 || status >= ARRAY_SIZE(status_map)); 159 160 return status_map[status]; 161 } 162 163 static void o2dlm_lock_ast_wrapper(void *astarg) 164 { 165 struct ocfs2_dlm_lksb *lksb = astarg; 166 167 lksb->lksb_conn->cc_proto->lp_lock_ast(lksb); 168 } 169 170 static void o2dlm_blocking_ast_wrapper(void *astarg, int level) 171 { 172 struct ocfs2_dlm_lksb *lksb = astarg; 173 174 lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level); 175 } 176 177 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status) 178 { 179 struct ocfs2_dlm_lksb *lksb = astarg; 180 int error = dlm_status_to_errno(status); 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 lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, error); 197 } 198 199 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn, 200 int mode, 201 struct ocfs2_dlm_lksb *lksb, 202 u32 flags, 203 void *name, 204 unsigned int namelen) 205 { 206 enum dlm_status status; 207 int o2dlm_mode = mode_to_o2dlm(mode); 208 int o2dlm_flags = flags_to_o2dlm(flags); 209 int ret; 210 211 status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm, 212 o2dlm_flags, name, namelen, 213 o2dlm_lock_ast_wrapper, lksb, 214 o2dlm_blocking_ast_wrapper); 215 ret = dlm_status_to_errno(status); 216 return ret; 217 } 218 219 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn, 220 struct ocfs2_dlm_lksb *lksb, 221 u32 flags) 222 { 223 enum dlm_status status; 224 int o2dlm_flags = flags_to_o2dlm(flags); 225 int ret; 226 227 status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm, 228 o2dlm_flags, o2dlm_unlock_ast_wrapper, lksb); 229 ret = dlm_status_to_errno(status); 230 return ret; 231 } 232 233 static int o2cb_dlm_lock_status(struct ocfs2_dlm_lksb *lksb) 234 { 235 return dlm_status_to_errno(lksb->lksb_o2dlm.status); 236 } 237 238 /* 239 * o2dlm aways has a "valid" LVB. If the dlm loses track of the LVB 240 * contents, it will zero out the LVB. Thus the caller can always trust 241 * the contents. 242 */ 243 static int o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb) 244 { 245 return 1; 246 } 247 248 static void *o2cb_dlm_lvb(struct ocfs2_dlm_lksb *lksb) 249 { 250 return (void *)(lksb->lksb_o2dlm.lvb); 251 } 252 253 static void o2cb_dump_lksb(struct ocfs2_dlm_lksb *lksb) 254 { 255 dlm_print_one_lock(lksb->lksb_o2dlm.lockid); 256 } 257 258 /* 259 * Called from the dlm when it's about to evict a node. This is how the 260 * classic stack signals node death. 261 */ 262 static void o2dlm_eviction_cb(int node_num, void *data) 263 { 264 struct ocfs2_cluster_connection *conn = data; 265 266 mlog(ML_NOTICE, "o2dlm has evicted node %d from group %.*s\n", 267 node_num, conn->cc_namelen, conn->cc_name); 268 269 conn->cc_recovery_handler(node_num, conn->cc_recovery_data); 270 } 271 272 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn) 273 { 274 int rc = 0; 275 u32 dlm_key; 276 struct dlm_ctxt *dlm; 277 struct o2dlm_private *priv; 278 struct dlm_protocol_version fs_version; 279 280 BUG_ON(conn == NULL); 281 BUG_ON(conn->cc_proto == NULL); 282 283 /* for now we only have one cluster/node, make sure we see it 284 * in the heartbeat universe */ 285 if (!o2hb_check_local_node_heartbeating()) { 286 if (o2hb_global_heartbeat_active()) 287 mlog(ML_ERROR, "Global heartbeat not started\n"); 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 fs_version.pv_major = conn->cc_version.pv_major; 308 fs_version.pv_minor = conn->cc_version.pv_minor; 309 310 dlm = dlm_register_domain(conn->cc_name, dlm_key, &fs_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 = fs_version.pv_major; 318 conn->cc_version.pv_minor = fs_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