1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #ifndef _SYS_FLOCK_IMPL_H 28 #define _SYS_FLOCK_IMPL_H 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 #include <sys/types.h> 33 #include <sys/fcntl.h> /* flock definition */ 34 #include <sys/file.h> /* FREAD etc */ 35 #include <sys/flock.h> /* RCMD etc */ 36 #include <sys/kmem.h> 37 #include <sys/user.h> 38 #include <sys/thread.h> 39 #include <sys/proc.h> 40 #include <sys/cred.h> 41 #include <sys/debug.h> 42 #include <sys/cmn_err.h> 43 #include <sys/errno.h> 44 #include <sys/systm.h> 45 #include <sys/vnode.h> 46 #include <sys/share.h> /* just to get GETSYSID def */ 47 48 #ifdef __cplusplus 49 extern "C" { 50 #endif 51 52 struct edge { 53 struct edge *edge_adj_next; /* adjacency list next */ 54 struct edge *edge_adj_prev; /* adjacency list prev */ 55 struct edge *edge_in_next; /* incoming edges list next */ 56 struct edge *edge_in_prev; /* incoming edges list prev */ 57 struct lock_descriptor *from_vertex; /* edge emanating from lock */ 58 struct lock_descriptor *to_vertex; /* edge pointing to lock */ 59 }; 60 61 typedef struct edge edge_t; 62 63 struct lock_descriptor { 64 struct lock_descriptor *l_next; /* next active/sleep lock */ 65 struct lock_descriptor *l_prev; /* previous active/sleep lock */ 66 struct edge l_edge; /* edge for adj and in lists */ 67 struct lock_descriptor *l_stack; /* for stack operations */ 68 struct lock_descriptor *l_stack1; /* for stack operations */ 69 struct lock_descriptor *l_dstack; /* stack for debug functions */ 70 struct edge *l_sedge; /* start edge for graph alg. */ 71 int l_index; /* used for barrier count */ 72 struct graph *l_graph; /* graph this belongs to */ 73 vnode_t *l_vnode; /* vnode being locked */ 74 int l_type; /* type of lock */ 75 int l_state; /* state described below */ 76 u_offset_t l_start; /* start offset */ 77 u_offset_t l_end; /* end offset */ 78 flock64_t l_flock; /* original flock request */ 79 int l_color; /* color used for graph alg */ 80 kcondvar_t l_cv; /* wait condition for lock */ 81 int pvertex; /* index to proc vertex */ 82 int l_status; /* status described below */ 83 flk_nlm_status_t l_nlm_state; /* state of NLM server */ 84 flk_callback_t *l_callbacks; /* callbacks, or NULL */ 85 zoneid_t l_zoneid; /* zone of request */ 86 }; 87 88 typedef struct lock_descriptor lock_descriptor_t; 89 90 /* 91 * Each graph holds locking information for some number of vnodes. The 92 * active and sleeping lists are circular, with a dummy head element. 93 */ 94 95 struct graph { 96 kmutex_t gp_mutex; /* mutex for this graph */ 97 struct lock_descriptor active_locks; 98 struct lock_descriptor sleeping_locks; 99 int index; /* index of this graph into the hash table */ 100 int mark; /* used for coloring the graph */ 101 }; 102 103 typedef struct graph graph_t; 104 105 /* 106 * The possible states a lock can be in. These states are stored in the 107 * 'l_status' member of the 'lock_descriptor_t' structure. All locks start 108 * life in the INITIAL state, and end up in the DEAD state. Possible state 109 * transitions are : 110 * 111 * INITIAL--> START --> ACTIVE --> DEAD 112 * 113 * --> DEAD 114 * 115 * --> ACTIVE --> DEAD (new locks from flk_relation) 116 * 117 * --> SLEEPING --> GRANTED --> START --> ACTIVE --> DEAD 118 * 119 * --> INTR --> DEAD 120 * 121 * --> CANCELLED --> DEAD 122 * 123 * --> INTR --> DEAD 124 * 125 * --> INTR --> DEAD 126 * 127 * --> CANCELLED --> DEAD 128 * 129 * --> INTR --> DEAD 130 * 131 * Lock transitions are done in the following functions: 132 * --> INITIAL flk_get_lock(), reclock() 133 * --> START flk_execute_request() 134 * --> ACTIVE flk_insert_active_lock() 135 * --> SLEEPING flk_insert_sleeping_lock() 136 * --> GRANTED GRANT_WAKEUP 137 * --> INTERRUPTED INTERRUPT_WAKEUP 138 * --> CANCELLED CANCEL_WAKEUP 139 * --> DEAD reclock(), flk_delete_active_lock(), and 140 * flk_cancel_sleeping_lock() 141 */ 142 143 #define FLK_INITIAL_STATE 1 /* Initial state of all requests */ 144 #define FLK_START_STATE 2 /* Request has started execution */ 145 #define FLK_ACTIVE_STATE 3 /* In active queue */ 146 #define FLK_SLEEPING_STATE 4 /* Request is blocked */ 147 #define FLK_GRANTED_STATE 5 /* Request is granted */ 148 #define FLK_INTERRUPTED_STATE 6 /* Request is interrupted */ 149 #define FLK_CANCELLED_STATE 7 /* Request is cancelled */ 150 #define FLK_DEAD_STATE 8 /* Request is done - will be deleted */ 151 152 /* flags defining state of locks */ 153 154 /* 155 * The LLM design has been modified so that lock states are now stored 156 * in the l_status field of lock_descriptor_t. The l_state field is 157 * currently preserved for binary compatibility, but may be modified or 158 * removed in a minor release of Solaris. Note that both of these 159 * fields (and the rest of the lock_descriptor_t structure) are private 160 * to the implementation of the lock manager and should not be used 161 * externally. 162 */ 163 164 #define ACTIVE_LOCK 0x0001 /* in active queue */ 165 #define SLEEPING_LOCK 0x0002 /* in sleep queue */ 166 #define IO_LOCK 0x0004 /* is an IO lock */ 167 #define REFERENCED_LOCK 0x0008 /* referenced some where */ 168 #define QUERY_LOCK 0x0010 /* querying about lock */ 169 #define WILLING_TO_SLEEP_LOCK 0x0020 /* lock can be put in sleep queue */ 170 #define RECOMPUTE_LOCK 0x0040 /* used for recomputing dependencies */ 171 #define RECOMPUTE_DONE 0x0080 /* used for recomputing dependencies */ 172 #define BARRIER_LOCK 0x0100 /* used for recomputing dependencies */ 173 #define GRANTED_LOCK 0x0200 /* granted but still in sleep queue */ 174 #define CANCELLED_LOCK 0x0400 /* cancelled will be thrown out */ 175 #define DELETED_LOCK 0x0800 /* deleted - free at earliest */ 176 #define INTERRUPTED_LOCK 0x1000 /* pretend signal */ 177 #define LOCKMGR_LOCK 0x2000 /* remote lock (server-side) */ 178 /* Clustering: flag for PXFS locks */ 179 #define PXFS_LOCK 0x4000 /* lock created by PXFS file system */ 180 #define NBMAND_LOCK 0x8000 /* non-blocking mandatory locking */ 181 182 #define HASH_SIZE 32 183 #define HASH_SHIFT (HASH_SIZE - 1) 184 #define HASH_INDEX(vp) (((uintptr_t)vp >> 7) & HASH_SHIFT) 185 186 /* extern definitions */ 187 188 extern struct graph *lock_graph[HASH_SIZE]; 189 extern struct kmem_cache *flk_edge_cache; 190 191 /* Clustering: functions called by PXFS */ 192 int flk_execute_request(lock_descriptor_t *); 193 void flk_cancel_sleeping_lock(lock_descriptor_t *, int); 194 void flk_set_state(lock_descriptor_t *, int); 195 graph_t *flk_get_lock_graph(vnode_t *, int); 196 197 /* flags used for readability in flock.c */ 198 199 #define FLK_USE_GRAPH 0 /* don't initialize the lock_graph */ 200 #define FLK_INIT_GRAPH 1 /* initialize the lock graph */ 201 #define NO_COLOR 0 /* vertex is not colored */ 202 #define NO_CHECK_CYCLE 0 /* don't mark vertex's in flk_add_edge */ 203 #define CHECK_CYCLE 1 /* mark vertex's in flk_add_edge */ 204 205 #define SAME_OWNER(lock1, lock2) \ 206 (((lock1)->l_flock.l_pid == (lock2)->l_flock.l_pid) && \ 207 ((lock1)->l_flock.l_sysid == (lock2)->l_flock.l_sysid)) 208 209 #define COLORED(vertex) ((vertex)->l_color == (vertex)->l_graph->mark) 210 #define COLOR(vertex) ((vertex)->l_color = (vertex)->l_graph->mark) 211 212 /* 213 * stack data structure and operations 214 */ 215 216 #define STACK_INIT(stack) ((stack) = NULL) 217 #define STACK_PUSH(stack, ptr, stack_link) (ptr)->stack_link = (stack),\ 218 (stack) = (ptr) 219 #define STACK_POP(stack, stack_link) (stack) = (stack)->stack_link 220 #define STACK_TOP(stack) (stack) 221 #define STACK_EMPTY(stack) ((stack) == NULL) 222 223 224 #define ACTIVE_HEAD(gp) (&(gp)->active_locks) 225 226 #define SLEEPING_HEAD(gp) (&(gp)->sleeping_locks) 227 228 #define SET_LOCK_TO_FIRST_ACTIVE_VP(gp, lock, vp) \ 229 { \ 230 (lock) = (lock_descriptor_t *)vp->v_filocks; \ 231 } 232 233 #define SET_LOCK_TO_FIRST_SLEEP_VP(gp, lock, vp) \ 234 { \ 235 for ((lock) = SLEEPING_HEAD((gp))->l_next; ((lock) != SLEEPING_HEAD((gp)) && \ 236 (lock)->l_vnode != (vp)); (lock) = (lock)->l_next) \ 237 ; \ 238 (lock) = ((lock) == SLEEPING_HEAD((gp))) ? NULL : (lock); \ 239 } 240 241 #define OVERLAP(lock1, lock2) \ 242 (((lock1)->l_start <= (lock2)->l_start && \ 243 (lock2)->l_start <= (lock1)->l_end) || \ 244 ((lock2)->l_start <= (lock1)->l_start && \ 245 (lock1)->l_start <= (lock2)->l_end)) 246 247 #define IS_INITIAL(lock) ((lock)->l_status == FLK_INITIAL_STATE) 248 #define IS_ACTIVE(lock) ((lock)->l_status == FLK_ACTIVE_STATE) 249 #define IS_SLEEPING(lock) ((lock)->l_status == FLK_SLEEPING_STATE) 250 #define IS_GRANTED(lock) ((lock)->l_status == FLK_GRANTED_STATE) 251 #define IS_INTERRUPTED(lock) ((lock)->l_status == FLK_INTERRUPTED_STATE) 252 #define IS_CANCELLED(lock) ((lock)->l_status == FLK_CANCELLED_STATE) 253 #define IS_DEAD(lock) ((lock)->l_status == FLK_DEAD_STATE) 254 255 #define IS_QUERY_LOCK(lock) ((lock)->l_state & QUERY_LOCK) 256 #define IS_RECOMPUTE(lock) ((lock)->l_state & RECOMPUTE_LOCK) 257 #define IS_BARRIER(lock) ((lock)->l_state & BARRIER_LOCK) 258 #define IS_DELETED(lock) ((lock)->l_state & DELETED_LOCK) 259 #define IS_REFERENCED(lock) ((lock)->l_state & REFERENCED_LOCK) 260 #define IS_IO_LOCK(lock) ((lock)->l_state & IO_LOCK) 261 #define IS_WILLING_TO_SLEEP(lock) \ 262 ((lock)->l_state & WILLING_TO_SLEEP_LOCK) 263 #define IS_LOCKMGR(lock) ((lock)->l_state & LOCKMGR_LOCK) 264 #define IS_NLM_UP(lock) ((lock)->l_nlm_state == FLK_NLM_UP) 265 /* Clustering: Macro for PXFS locks */ 266 #define IS_PXFS(lock) ((lock)->l_state & PXFS_LOCK) 267 268 /* 269 * "local" requests don't involve the NFS lock manager in any way. 270 * "remote" requests can be on the server (requests from a remote client), 271 * in which case they should be associated with a local vnode (UFS, tmpfs, 272 * etc.). These requests are flagged with LOCKMGR_LOCK and are made using 273 * kernel service threads. Remote requests can also be on an NFS client, 274 * because the NFS lock manager uses local locking for some of its 275 * bookkeeping. These requests are made by regular user processes. 276 */ 277 #define IS_LOCAL(lock) (GETSYSID((lock)->l_flock.l_sysid) == 0) 278 #define IS_REMOTE(lock) (! IS_LOCAL(lock)) 279 280 /* Clustering: Return value for blocking PXFS locks */ 281 /* 282 * For PXFS locks, reclock() will return this error code for requests that 283 * need to block 284 */ 285 #define PXFS_LOCK_BLOCKED -1 286 287 /* Clustering: PXFS callback function */ 288 /* 289 * This function is a callback from the LLM into the PXFS server module. It 290 * is initialized as a weak stub, and is functional when the pxfs server module 291 * is loaded. 292 */ 293 extern void cl_flk_state_transition_notify(lock_descriptor_t *lock, 294 int old_state, int new_state); 295 296 #define BLOCKS(lock1, lock2) (!SAME_OWNER((lock1), (lock2)) && \ 297 (((lock1)->l_type == F_WRLCK) || \ 298 ((lock2)->l_type == F_WRLCK)) && \ 299 OVERLAP((lock1), (lock2))) 300 301 #define COVERS(lock1, lock2) \ 302 (((lock1)->l_start <= (lock2)->l_start) && \ 303 ((lock1)->l_end >= (lock2)->l_end)) 304 305 #define IN_LIST_REMOVE(ep) \ 306 { \ 307 (ep)->edge_in_next->edge_in_prev = (ep)->edge_in_prev; \ 308 (ep)->edge_in_prev->edge_in_next = (ep)->edge_in_next; \ 309 } 310 311 #define ADJ_LIST_REMOVE(ep) \ 312 { \ 313 (ep)->edge_adj_next->edge_adj_prev = (ep)->edge_adj_prev; \ 314 (ep)->edge_adj_prev->edge_adj_next = (ep)->edge_adj_next; \ 315 } 316 317 #define NOT_BLOCKED(lock) \ 318 ((lock)->l_edge.edge_adj_next == &(lock)->l_edge && !IS_GRANTED(lock)) 319 320 #define GRANT_WAKEUP(lock) \ 321 { \ 322 flk_set_state(lock, FLK_GRANTED_STATE); \ 323 (lock)->l_state |= GRANTED_LOCK; \ 324 /* \ 325 * Clustering: PXFS locks do not sleep in the LLM, \ 326 * so there is no need to signal them \ 327 */ \ 328 if (!IS_PXFS(lock)) { \ 329 cv_signal(&(lock)->l_cv); \ 330 } \ 331 } 332 333 #define CANCEL_WAKEUP(lock) \ 334 { \ 335 flk_set_state(lock, FLK_CANCELLED_STATE); \ 336 (lock)->l_state |= CANCELLED_LOCK; \ 337 /* \ 338 * Clustering: PXFS locks do not sleep in the LLM, \ 339 * so there is no need to signal them \ 340 */ \ 341 if (!IS_PXFS(lock)) { \ 342 cv_signal(&(lock)->l_cv); \ 343 } \ 344 } 345 346 #define INTERRUPT_WAKEUP(lock) \ 347 { \ 348 flk_set_state(lock, FLK_INTERRUPTED_STATE); \ 349 (lock)->l_state |= INTERRUPTED_LOCK; \ 350 /* \ 351 * Clustering: PXFS locks do not sleep in the LLM, \ 352 * so there is no need to signal them \ 353 */ \ 354 if (!IS_PXFS(lock)) { \ 355 cv_signal(&(lock)->l_cv); \ 356 } \ 357 } 358 359 #define REMOVE_SLEEP_QUEUE(lock) \ 360 { \ 361 ASSERT(IS_SLEEPING(lock) || IS_GRANTED(lock) || \ 362 IS_INTERRUPTED(lock) || IS_CANCELLED(lock)); \ 363 (lock)->l_state &= ~SLEEPING_LOCK; \ 364 (lock)->l_next->l_prev = (lock)->l_prev; \ 365 (lock)->l_prev->l_next = (lock)->l_next; \ 366 (lock)->l_next = (lock)->l_prev = (lock_descriptor_t *)NULL; \ 367 } 368 369 #define NO_DEPENDENTS(lock) \ 370 ((lock)->l_edge.edge_in_next == &(lock)->l_edge) 371 372 #define GRANT(lock) \ 373 { \ 374 (lock)->l_state |= GRANTED_LOCK; \ 375 flk_set_state(lock, FLK_GRANTED_STATE); \ 376 } 377 378 #define FIRST_IN(lock) ((lock)->l_edge.edge_in_next) 379 #define FIRST_ADJ(lock) ((lock)->l_edge.edge_adj_next) 380 #define HEAD(lock) (&(lock)->l_edge) 381 #define NEXT_ADJ(ep) ((ep)->edge_adj_next) 382 #define NEXT_IN(ep) ((ep)->edge_in_next) 383 #define IN_ADJ_INIT(lock) \ 384 { \ 385 (lock)->l_edge.edge_adj_next = (lock)->l_edge.edge_adj_prev = &(lock)->l_edge; \ 386 (lock)->l_edge.edge_in_next = (lock)->l_edge.edge_in_prev = &(lock)->l_edge; \ 387 } 388 389 #define COPY(lock1, lock2) \ 390 { \ 391 (lock1)->l_graph = (lock2)->l_graph; \ 392 (lock1)->l_vnode = (lock2)->l_vnode; \ 393 (lock1)->l_type = (lock2)->l_type; \ 394 (lock1)->l_state = (lock2)->l_state; \ 395 (lock1)->l_start = (lock2)->l_start; \ 396 (lock1)->l_end = (lock2)->l_end; \ 397 (lock1)->l_flock = (lock2)->l_flock; \ 398 (lock1)->l_zoneid = (lock2)->l_zoneid; \ 399 (lock1)->pvertex = (lock2)->pvertex; \ 400 } 401 402 /* 403 * Clustering 404 */ 405 /* Routines to set and get the NLM state in a lock request */ 406 #define SET_NLM_STATE(lock, nlm_state) ((lock)->l_nlm_state = nlm_state) 407 #define GET_NLM_STATE(lock) ((lock)->l_nlm_state) 408 /* 409 * NLM registry abstraction: 410 * Abstraction overview: 411 * This registry keeps track of the NLM servers via their nlmids 412 * that have requested locks at the LLM this registry is associated 413 * with. 414 */ 415 /* Routines to manipulate the NLM registry object state */ 416 #define FLK_REGISTRY_IS_NLM_UNKNOWN(nlmreg, nlmid) \ 417 ((nlmreg)[nlmid] == FLK_NLM_UNKNOWN) 418 #define FLK_REGISTRY_IS_NLM_UP(nlmreg, nlmid) \ 419 ((nlmreg)[nlmid] == FLK_NLM_UP) 420 #define FLK_REGISTRY_ADD_NLMID(nlmreg, nlmid) \ 421 ((nlmreg)[nlmid] = FLK_NLM_UP) 422 #define FLK_REGISTRY_CHANGE_NLM_STATE(nlmreg, nlmid, state) \ 423 ((nlmreg)[nlmid] = state) 424 425 /* Indicates the effect of executing a request on the existing locks */ 426 427 #define FLK_UNLOCK 0x1 /* request unlocks the existing lock */ 428 #define FLK_DOWNGRADE 0x2 /* request downgrades the existing lock */ 429 #define FLK_UPGRADE 0x3 /* request upgrades the existing lock */ 430 #define FLK_STAY_SAME 0x4 /* request type is same as existing lock */ 431 432 433 /* proc graph definitions */ 434 435 /* 436 * Proc graph is the global process graph that maintains information 437 * about the dependencies between processes. An edge is added between two 438 * processes represented by proc_vertex's A and B, iff there exists l1 439 * owned by process A in any of the lock_graph's dependent on l2 440 * (thus having an edge to l2) owned by process B. 441 */ 442 struct proc_vertex { 443 pid_t pid; /* pid of the process */ 444 long sysid; /* sysid of the process */ 445 struct proc_edge *edge; /* adajcent edges of this process */ 446 int incount; /* Number of inedges to this process */ 447 struct proc_edge *p_sedge; /* used for implementing stack alg. */ 448 struct proc_vertex *p_stack; /* used for stack alg. */ 449 int atime; /* used for cycle detection algorithm */ 450 int dtime; /* used for cycle detection algorithm */ 451 int index; /* index into the array of proc_graph vertices */ 452 }; 453 454 typedef struct proc_vertex proc_vertex_t; 455 456 struct proc_edge { 457 struct proc_edge *next; /* next edge in adjacency list */ 458 int refcount; /* reference count of this edge */ 459 struct proc_vertex *to_proc; /* process this points to */ 460 }; 461 462 typedef struct proc_edge proc_edge_t; 463 464 465 #define PROC_CHUNK 100 466 467 struct proc_graph { 468 struct proc_vertex **proc; /* list of proc_vertexes */ 469 int gcount; /* list size */ 470 int free; /* number of free slots in the list */ 471 int mark; /* used for graph coloring */ 472 }; 473 474 typedef struct proc_graph proc_graph_t; 475 476 extern struct proc_graph pgraph; 477 478 #define PROC_SAME_OWNER(lock, pvertex) \ 479 (((lock)->l_flock.l_pid == (pvertex)->pid) && \ 480 ((lock)->l_flock.l_sysid == (pvertex)->sysid)) 481 482 #define PROC_ARRIVE(pvertex) ((pvertex)->atime = pgraph.mark) 483 #define PROC_DEPART(pvertex) ((pvertex)->dtime = pgraph.mark) 484 #define PROC_ARRIVED(pvertex) ((pvertex)->atime == pgraph.mark) 485 #define PROC_DEPARTED(pvertex) ((pvertex)->dtime == pgraph.mark) 486 487 #ifdef __cplusplus 488 } 489 #endif 490 491 #endif /* _SYS_FLOCK_IMPL_H */ 492