1/* Internal definitions for FS-Cache 2 * 3 * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved. 4 * Written by David Howells (dhowells@redhat.com) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12/* 13 * Lock order, in the order in which multiple locks should be obtained: 14 * - fscache_addremove_sem 15 * - cookie->lock 16 * - cookie->parent->lock 17 * - cache->object_list_lock 18 * - object->lock 19 * - object->parent->lock 20 * - cookie->stores_lock 21 * - fscache_thread_lock 22 * 23 */ 24 25#ifdef pr_fmt 26#undef pr_fmt 27#endif 28 29#define pr_fmt(fmt) "FS-Cache: " fmt 30 31#include <linux/fscache-cache.h> 32#include <linux/sched.h> 33 34#define FSCACHE_MIN_THREADS 4 35#define FSCACHE_MAX_THREADS 32 36 37/* 38 * cache.c 39 */ 40extern struct list_head fscache_cache_list; 41extern struct rw_semaphore fscache_addremove_sem; 42 43extern struct fscache_cache *fscache_select_cache_for_object( 44 struct fscache_cookie *); 45 46/* 47 * cookie.c 48 */ 49extern struct kmem_cache *fscache_cookie_jar; 50 51extern void fscache_cookie_init_once(void *); 52extern void __fscache_cookie_put(struct fscache_cookie *); 53 54/* 55 * fsdef.c 56 */ 57extern struct fscache_cookie fscache_fsdef_index; 58extern struct fscache_cookie_def fscache_fsdef_netfs_def; 59 60/* 61 * histogram.c 62 */ 63#ifdef CONFIG_FSCACHE_HISTOGRAM 64extern atomic_t fscache_obj_instantiate_histogram[HZ]; 65extern atomic_t fscache_objs_histogram[HZ]; 66extern atomic_t fscache_ops_histogram[HZ]; 67extern atomic_t fscache_retrieval_delay_histogram[HZ]; 68extern atomic_t fscache_retrieval_histogram[HZ]; 69 70static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif) 71{ 72 unsigned long jif = jiffies - start_jif; 73 if (jif >= HZ) 74 jif = HZ - 1; 75 atomic_inc(&histogram[jif]); 76} 77 78extern const struct file_operations fscache_histogram_fops; 79 80#else 81#define fscache_hist(hist, start_jif) do {} while (0) 82#endif 83 84/* 85 * main.c 86 */ 87extern unsigned fscache_defer_lookup; 88extern unsigned fscache_defer_create; 89extern unsigned fscache_debug; 90extern struct kobject *fscache_root; 91extern struct workqueue_struct *fscache_object_wq; 92extern struct workqueue_struct *fscache_op_wq; 93DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait); 94 95static inline bool fscache_object_congested(void) 96{ 97 return workqueue_congested(WORK_CPU_UNBOUND, fscache_object_wq); 98} 99 100extern int fscache_wait_atomic_t(atomic_t *); 101 102/* 103 * object.c 104 */ 105extern void fscache_enqueue_object(struct fscache_object *); 106 107/* 108 * object-list.c 109 */ 110#ifdef CONFIG_FSCACHE_OBJECT_LIST 111extern const struct file_operations fscache_objlist_fops; 112 113extern void fscache_objlist_add(struct fscache_object *); 114extern void fscache_objlist_remove(struct fscache_object *); 115#else 116#define fscache_objlist_add(object) do {} while(0) 117#define fscache_objlist_remove(object) do {} while(0) 118#endif 119 120/* 121 * operation.c 122 */ 123extern int fscache_submit_exclusive_op(struct fscache_object *, 124 struct fscache_operation *); 125extern int fscache_submit_op(struct fscache_object *, 126 struct fscache_operation *); 127extern int fscache_cancel_op(struct fscache_operation *, 128 void (*)(struct fscache_operation *)); 129extern void fscache_cancel_all_ops(struct fscache_object *); 130extern void fscache_abort_object(struct fscache_object *); 131extern void fscache_start_operations(struct fscache_object *); 132extern void fscache_operation_gc(struct work_struct *); 133 134/* 135 * page.c 136 */ 137extern int fscache_wait_for_deferred_lookup(struct fscache_cookie *); 138extern int fscache_wait_for_operation_activation(struct fscache_object *, 139 struct fscache_operation *, 140 atomic_t *, 141 atomic_t *, 142 void (*)(struct fscache_operation *)); 143extern void fscache_invalidate_writes(struct fscache_cookie *); 144 145/* 146 * proc.c 147 */ 148#ifdef CONFIG_PROC_FS 149extern int __init fscache_proc_init(void); 150extern void fscache_proc_cleanup(void); 151#else 152#define fscache_proc_init() (0) 153#define fscache_proc_cleanup() do {} while (0) 154#endif 155 156/* 157 * stats.c 158 */ 159#ifdef CONFIG_FSCACHE_STATS 160extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS]; 161extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS]; 162 163extern atomic_t fscache_n_op_pend; 164extern atomic_t fscache_n_op_run; 165extern atomic_t fscache_n_op_enqueue; 166extern atomic_t fscache_n_op_deferred_release; 167extern atomic_t fscache_n_op_release; 168extern atomic_t fscache_n_op_gc; 169extern atomic_t fscache_n_op_cancelled; 170extern atomic_t fscache_n_op_rejected; 171 172extern atomic_t fscache_n_attr_changed; 173extern atomic_t fscache_n_attr_changed_ok; 174extern atomic_t fscache_n_attr_changed_nobufs; 175extern atomic_t fscache_n_attr_changed_nomem; 176extern atomic_t fscache_n_attr_changed_calls; 177 178extern atomic_t fscache_n_allocs; 179extern atomic_t fscache_n_allocs_ok; 180extern atomic_t fscache_n_allocs_wait; 181extern atomic_t fscache_n_allocs_nobufs; 182extern atomic_t fscache_n_allocs_intr; 183extern atomic_t fscache_n_allocs_object_dead; 184extern atomic_t fscache_n_alloc_ops; 185extern atomic_t fscache_n_alloc_op_waits; 186 187extern atomic_t fscache_n_retrievals; 188extern atomic_t fscache_n_retrievals_ok; 189extern atomic_t fscache_n_retrievals_wait; 190extern atomic_t fscache_n_retrievals_nodata; 191extern atomic_t fscache_n_retrievals_nobufs; 192extern atomic_t fscache_n_retrievals_intr; 193extern atomic_t fscache_n_retrievals_nomem; 194extern atomic_t fscache_n_retrievals_object_dead; 195extern atomic_t fscache_n_retrieval_ops; 196extern atomic_t fscache_n_retrieval_op_waits; 197 198extern atomic_t fscache_n_stores; 199extern atomic_t fscache_n_stores_ok; 200extern atomic_t fscache_n_stores_again; 201extern atomic_t fscache_n_stores_nobufs; 202extern atomic_t fscache_n_stores_oom; 203extern atomic_t fscache_n_store_ops; 204extern atomic_t fscache_n_store_calls; 205extern atomic_t fscache_n_store_pages; 206extern atomic_t fscache_n_store_radix_deletes; 207extern atomic_t fscache_n_store_pages_over_limit; 208 209extern atomic_t fscache_n_store_vmscan_not_storing; 210extern atomic_t fscache_n_store_vmscan_gone; 211extern atomic_t fscache_n_store_vmscan_busy; 212extern atomic_t fscache_n_store_vmscan_cancelled; 213extern atomic_t fscache_n_store_vmscan_wait; 214 215extern atomic_t fscache_n_marks; 216extern atomic_t fscache_n_uncaches; 217 218extern atomic_t fscache_n_acquires; 219extern atomic_t fscache_n_acquires_null; 220extern atomic_t fscache_n_acquires_no_cache; 221extern atomic_t fscache_n_acquires_ok; 222extern atomic_t fscache_n_acquires_nobufs; 223extern atomic_t fscache_n_acquires_oom; 224 225extern atomic_t fscache_n_invalidates; 226extern atomic_t fscache_n_invalidates_run; 227 228extern atomic_t fscache_n_updates; 229extern atomic_t fscache_n_updates_null; 230extern atomic_t fscache_n_updates_run; 231 232extern atomic_t fscache_n_relinquishes; 233extern atomic_t fscache_n_relinquishes_null; 234extern atomic_t fscache_n_relinquishes_waitcrt; 235extern atomic_t fscache_n_relinquishes_retire; 236 237extern atomic_t fscache_n_cookie_index; 238extern atomic_t fscache_n_cookie_data; 239extern atomic_t fscache_n_cookie_special; 240 241extern atomic_t fscache_n_object_alloc; 242extern atomic_t fscache_n_object_no_alloc; 243extern atomic_t fscache_n_object_lookups; 244extern atomic_t fscache_n_object_lookups_negative; 245extern atomic_t fscache_n_object_lookups_positive; 246extern atomic_t fscache_n_object_lookups_timed_out; 247extern atomic_t fscache_n_object_created; 248extern atomic_t fscache_n_object_avail; 249extern atomic_t fscache_n_object_dead; 250 251extern atomic_t fscache_n_checkaux_none; 252extern atomic_t fscache_n_checkaux_okay; 253extern atomic_t fscache_n_checkaux_update; 254extern atomic_t fscache_n_checkaux_obsolete; 255 256extern atomic_t fscache_n_cop_alloc_object; 257extern atomic_t fscache_n_cop_lookup_object; 258extern atomic_t fscache_n_cop_lookup_complete; 259extern atomic_t fscache_n_cop_grab_object; 260extern atomic_t fscache_n_cop_invalidate_object; 261extern atomic_t fscache_n_cop_update_object; 262extern atomic_t fscache_n_cop_drop_object; 263extern atomic_t fscache_n_cop_put_object; 264extern atomic_t fscache_n_cop_sync_cache; 265extern atomic_t fscache_n_cop_attr_changed; 266extern atomic_t fscache_n_cop_read_or_alloc_page; 267extern atomic_t fscache_n_cop_read_or_alloc_pages; 268extern atomic_t fscache_n_cop_allocate_page; 269extern atomic_t fscache_n_cop_allocate_pages; 270extern atomic_t fscache_n_cop_write_page; 271extern atomic_t fscache_n_cop_uncache_page; 272extern atomic_t fscache_n_cop_dissociate_pages; 273 274static inline void fscache_stat(atomic_t *stat) 275{ 276 atomic_inc(stat); 277} 278 279static inline void fscache_stat_d(atomic_t *stat) 280{ 281 atomic_dec(stat); 282} 283 284#define __fscache_stat(stat) (stat) 285 286extern const struct file_operations fscache_stats_fops; 287#else 288 289#define __fscache_stat(stat) (NULL) 290#define fscache_stat(stat) do {} while (0) 291#define fscache_stat_d(stat) do {} while (0) 292#endif 293 294/* 295 * raise an event on an object 296 * - if the event is not masked for that object, then the object is 297 * queued for attention by the thread pool. 298 */ 299static inline void fscache_raise_event(struct fscache_object *object, 300 unsigned event) 301{ 302 BUG_ON(event >= NR_FSCACHE_OBJECT_EVENTS); 303#if 0 304 printk("*** fscache_raise_event(OBJ%d{%lx},%x)\n", 305 object->debug_id, object->event_mask, (1 << event)); 306#endif 307 if (!test_and_set_bit(event, &object->events) && 308 test_bit(event, &object->event_mask)) 309 fscache_enqueue_object(object); 310} 311 312/* 313 * drop a reference to a cookie 314 */ 315static inline void fscache_cookie_put(struct fscache_cookie *cookie) 316{ 317 BUG_ON(atomic_read(&cookie->usage) <= 0); 318 if (atomic_dec_and_test(&cookie->usage)) 319 __fscache_cookie_put(cookie); 320} 321 322/* 323 * get an extra reference to a netfs retrieval context 324 */ 325static inline 326void *fscache_get_context(struct fscache_cookie *cookie, void *context) 327{ 328 if (cookie->def->get_context) 329 cookie->def->get_context(cookie->netfs_data, context); 330 return context; 331} 332 333/* 334 * release a reference to a netfs retrieval context 335 */ 336static inline 337void fscache_put_context(struct fscache_cookie *cookie, void *context) 338{ 339 if (cookie->def->put_context) 340 cookie->def->put_context(cookie->netfs_data, context); 341} 342 343/*****************************************************************************/ 344/* 345 * debug tracing 346 */ 347#define dbgprintk(FMT, ...) \ 348 printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__) 349 350#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) 351#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 352#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__) 353 354#define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__) 355 356#ifdef __KDEBUG 357#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__) 358#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__) 359#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__) 360 361#elif defined(CONFIG_FSCACHE_DEBUG) 362#define _enter(FMT, ...) \ 363do { \ 364 if (__do_kdebug(ENTER)) \ 365 kenter(FMT, ##__VA_ARGS__); \ 366} while (0) 367 368#define _leave(FMT, ...) \ 369do { \ 370 if (__do_kdebug(LEAVE)) \ 371 kleave(FMT, ##__VA_ARGS__); \ 372} while (0) 373 374#define _debug(FMT, ...) \ 375do { \ 376 if (__do_kdebug(DEBUG)) \ 377 kdebug(FMT, ##__VA_ARGS__); \ 378} while (0) 379 380#else 381#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__) 382#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 383#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__) 384#endif 385 386/* 387 * determine whether a particular optional debugging point should be logged 388 * - we need to go through three steps to persuade cpp to correctly join the 389 * shorthand in FSCACHE_DEBUG_LEVEL with its prefix 390 */ 391#define ____do_kdebug(LEVEL, POINT) \ 392 unlikely((fscache_debug & \ 393 (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3)))) 394#define ___do_kdebug(LEVEL, POINT) \ 395 ____do_kdebug(LEVEL, POINT) 396#define __do_kdebug(POINT) \ 397 ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT) 398 399#define FSCACHE_DEBUG_CACHE 0 400#define FSCACHE_DEBUG_COOKIE 1 401#define FSCACHE_DEBUG_PAGE 2 402#define FSCACHE_DEBUG_OPERATION 3 403 404#define FSCACHE_POINT_ENTER 1 405#define FSCACHE_POINT_LEAVE 2 406#define FSCACHE_POINT_DEBUG 4 407 408#ifndef FSCACHE_DEBUG_LEVEL 409#define FSCACHE_DEBUG_LEVEL CACHE 410#endif 411 412/* 413 * assertions 414 */ 415#if 1 /* defined(__KDEBUGALL) */ 416 417#define ASSERT(X) \ 418do { \ 419 if (unlikely(!(X))) { \ 420 pr_err("\n"); \ 421 pr_err("Assertion failed\n"); \ 422 BUG(); \ 423 } \ 424} while (0) 425 426#define ASSERTCMP(X, OP, Y) \ 427do { \ 428 if (unlikely(!((X) OP (Y)))) { \ 429 pr_err("\n"); \ 430 pr_err("Assertion failed\n"); \ 431 pr_err("%lx " #OP " %lx is false\n", \ 432 (unsigned long)(X), (unsigned long)(Y)); \ 433 BUG(); \ 434 } \ 435} while (0) 436 437#define ASSERTIF(C, X) \ 438do { \ 439 if (unlikely((C) && !(X))) { \ 440 pr_err("\n"); \ 441 pr_err("Assertion failed\n"); \ 442 BUG(); \ 443 } \ 444} while (0) 445 446#define ASSERTIFCMP(C, X, OP, Y) \ 447do { \ 448 if (unlikely((C) && !((X) OP (Y)))) { \ 449 pr_err("\n"); \ 450 pr_err("Assertion failed\n"); \ 451 pr_err("%lx " #OP " %lx is false\n", \ 452 (unsigned long)(X), (unsigned long)(Y)); \ 453 BUG(); \ 454 } \ 455} while (0) 456 457#else 458 459#define ASSERT(X) do {} while (0) 460#define ASSERTCMP(X, OP, Y) do {} while (0) 461#define ASSERTIF(C, X) do {} while (0) 462#define ASSERTIFCMP(C, X, OP, Y) do {} while (0) 463 464#endif /* assert or not */ 465