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 struct ocfs2_dlm_lksb *lksb = astarg; 165 166 lksb->lksb_conn->cc_proto->lp_lock_ast(lksb); 167 } 168 169 static void o2dlm_blocking_ast_wrapper(void *astarg, int level) 170 { 171 struct ocfs2_dlm_lksb *lksb = astarg; 172 173 lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level); 174 } 175 176 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status) 177 { 178 struct ocfs2_dlm_lksb *lksb = astarg; 179 int error = dlm_status_to_errno(status); 180 181 /* 182 * In o2dlm, you can get both the lock_ast() for the lock being 183 * granted and the unlock_ast() for the CANCEL failing. A 184 * successful cancel sends DLM_NORMAL here. If the 185 * lock grant happened before the cancel arrived, you get 186 * DLM_CANCELGRANT. 187 * 188 * There's no need for the double-ast. If we see DLM_CANCELGRANT, 189 * we just ignore it. We expect the lock_ast() to handle the 190 * granted lock. 191 */ 192 if (status == DLM_CANCELGRANT) 193 return; 194 195 lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, error); 196 } 197 198 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn, 199 int mode, 200 struct ocfs2_dlm_lksb *lksb, 201 u32 flags, 202 void *name, 203 unsigned int namelen) 204 { 205 enum dlm_status status; 206 int o2dlm_mode = mode_to_o2dlm(mode); 207 int o2dlm_flags = flags_to_o2dlm(flags); 208 int ret; 209 210 status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm, 211 o2dlm_flags, name, namelen, 212 o2dlm_lock_ast_wrapper, lksb, 213 o2dlm_blocking_ast_wrapper); 214 ret = dlm_status_to_errno(status); 215 return ret; 216 } 217 218 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn, 219 struct ocfs2_dlm_lksb *lksb, 220 u32 flags) 221 { 222 enum dlm_status status; 223 int o2dlm_flags = flags_to_o2dlm(flags); 224 int ret; 225 226 status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm, 227 o2dlm_flags, o2dlm_unlock_ast_wrapper, lksb); 228 ret = dlm_status_to_errno(status); 229 return ret; 230 } 231 232 static int o2cb_dlm_lock_status(struct ocfs2_dlm_lksb *lksb) 233 { 234 return dlm_status_to_errno(lksb->lksb_o2dlm.status); 235 } 236 237 /* 238 * o2dlm aways has a "valid" LVB. If the dlm loses track of the LVB 239 * contents, it will zero out the LVB. Thus the caller can always trust 240 * the contents. 241 */ 242 static int o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb) 243 { 244 return 1; 245 } 246 247 static void *o2cb_dlm_lvb(struct ocfs2_dlm_lksb *lksb) 248 { 249 return (void *)(lksb->lksb_o2dlm.lvb); 250 } 251 252 static void o2cb_dump_lksb(struct ocfs2_dlm_lksb *lksb) 253 { 254 dlm_print_one_lock(lksb->lksb_o2dlm.lockid); 255 } 256 257 /* 258 * Called from the dlm when it's about to evict a node. This is how the 259 * classic stack signals node death. 260 */ 261 static void o2dlm_eviction_cb(int node_num, void *data) 262 { 263 struct ocfs2_cluster_connection *conn = data; 264 265 mlog(ML_NOTICE, "o2dlm has evicted node %d from group %.*s\n", 266 node_num, conn->cc_namelen, conn->cc_name); 267 268 conn->cc_recovery_handler(node_num, conn->cc_recovery_data); 269 } 270 271 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn) 272 { 273 int rc = 0; 274 u32 dlm_key; 275 struct dlm_ctxt *dlm; 276 struct o2dlm_private *priv; 277 struct dlm_protocol_version fs_version; 278 279 BUG_ON(conn == NULL); 280 BUG_ON(conn->cc_proto == NULL); 281 282 /* for now we only have one cluster/node, make sure we see it 283 * in the heartbeat universe */ 284 if (!o2hb_check_local_node_heartbeating()) { 285 rc = -EINVAL; 286 goto out; 287 } 288 289 priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL); 290 if (!priv) { 291 rc = -ENOMEM; 292 goto out_free; 293 } 294 295 /* This just fills the structure in. It is safe to pass conn. */ 296 dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb, 297 conn); 298 299 conn->cc_private = priv; 300 301 /* used by the dlm code to make message headers unique, each 302 * node in this domain must agree on this. */ 303 dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen); 304 fs_version.pv_major = conn->cc_version.pv_major; 305 fs_version.pv_minor = conn->cc_version.pv_minor; 306 307 dlm = dlm_register_domain(conn->cc_name, dlm_key, &fs_version); 308 if (IS_ERR(dlm)) { 309 rc = PTR_ERR(dlm); 310 mlog_errno(rc); 311 goto out_free; 312 } 313 314 conn->cc_version.pv_major = fs_version.pv_major; 315 conn->cc_version.pv_minor = fs_version.pv_minor; 316 conn->cc_lockspace = dlm; 317 318 dlm_register_eviction_cb(dlm, &priv->op_eviction_cb); 319 320 out_free: 321 if (rc && conn->cc_private) 322 kfree(conn->cc_private); 323 324 out: 325 return rc; 326 } 327 328 static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn) 329 { 330 struct dlm_ctxt *dlm = conn->cc_lockspace; 331 struct o2dlm_private *priv = conn->cc_private; 332 333 dlm_unregister_eviction_cb(&priv->op_eviction_cb); 334 conn->cc_private = NULL; 335 kfree(priv); 336 337 dlm_unregister_domain(dlm); 338 conn->cc_lockspace = NULL; 339 340 return 0; 341 } 342 343 static int o2cb_cluster_this_node(unsigned int *node) 344 { 345 int node_num; 346 347 node_num = o2nm_this_node(); 348 if (node_num == O2NM_INVALID_NODE_NUM) 349 return -ENOENT; 350 351 if (node_num >= O2NM_MAX_NODES) 352 return -EOVERFLOW; 353 354 *node = node_num; 355 return 0; 356 } 357 358 static struct ocfs2_stack_operations o2cb_stack_ops = { 359 .connect = o2cb_cluster_connect, 360 .disconnect = o2cb_cluster_disconnect, 361 .this_node = o2cb_cluster_this_node, 362 .dlm_lock = o2cb_dlm_lock, 363 .dlm_unlock = o2cb_dlm_unlock, 364 .lock_status = o2cb_dlm_lock_status, 365 .lvb_valid = o2cb_dlm_lvb_valid, 366 .lock_lvb = o2cb_dlm_lvb, 367 .dump_lksb = o2cb_dump_lksb, 368 }; 369 370 static struct ocfs2_stack_plugin o2cb_stack = { 371 .sp_name = "o2cb", 372 .sp_ops = &o2cb_stack_ops, 373 .sp_owner = THIS_MODULE, 374 }; 375 376 static int __init o2cb_stack_init(void) 377 { 378 return ocfs2_stack_glue_register(&o2cb_stack); 379 } 380 381 static void __exit o2cb_stack_exit(void) 382 { 383 ocfs2_stack_glue_unregister(&o2cb_stack); 384 } 385 386 MODULE_AUTHOR("Oracle"); 387 MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack"); 388 MODULE_LICENSE("GPL"); 389 module_init(o2cb_stack_init); 390 module_exit(o2cb_stack_exit); 391