1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* Internal definitions for network filesystem support 3 * 4 * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8 #include <linux/slab.h> 9 #include <linux/seq_file.h> 10 #include <linux/folio_queue.h> 11 #include <linux/netfs.h> 12 #include <linux/fscache.h> 13 #include <linux/fscache-cache.h> 14 #include <trace/events/netfs.h> 15 #include <trace/events/fscache.h> 16 17 #ifdef pr_fmt 18 #undef pr_fmt 19 #endif 20 21 #define pr_fmt(fmt) "netfs: " fmt 22 23 /* 24 * buffered_read.c 25 */ 26 void netfs_queue_read(struct netfs_io_request *rreq, 27 struct netfs_io_subrequest *subreq); 28 void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error); 29 int netfs_prefetch_for_write(struct file *file, struct folio *folio, 30 size_t offset, size_t len); 31 32 /* 33 * buffered_write.c 34 */ 35 void netfs_update_i_size(struct netfs_inode *ctx, struct inode *inode, 36 loff_t pos, size_t copied); 37 38 /* 39 * main.c 40 */ 41 extern unsigned int netfs_debug; 42 extern struct list_head netfs_io_requests; 43 extern spinlock_t netfs_proc_lock; 44 extern mempool_t netfs_request_pool; 45 extern mempool_t netfs_subrequest_pool; 46 extern mempool_t netfs_folioq_pool; 47 48 #ifdef CONFIG_PROC_FS 49 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq) 50 { 51 spin_lock(&netfs_proc_lock); 52 list_add_tail_rcu(&rreq->proc_link, &netfs_io_requests); 53 spin_unlock(&netfs_proc_lock); 54 } 55 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq) 56 { 57 if (!list_empty(&rreq->proc_link)) { 58 spin_lock(&netfs_proc_lock); 59 list_del_rcu(&rreq->proc_link); 60 spin_unlock(&netfs_proc_lock); 61 } 62 } 63 #else 64 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq) {} 65 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq) {} 66 #endif 67 68 /* 69 * misc.c 70 */ 71 struct folio_queue *netfs_buffer_make_space(struct netfs_io_request *rreq, 72 enum netfs_folioq_trace trace); 73 void netfs_reset_iter(struct netfs_io_subrequest *subreq); 74 void netfs_wake_collector(struct netfs_io_request *rreq); 75 void netfs_subreq_clear_in_progress(struct netfs_io_subrequest *subreq); 76 void netfs_wait_for_in_progress_stream(struct netfs_io_request *rreq, 77 struct netfs_io_stream *stream); 78 ssize_t netfs_wait_for_read(struct netfs_io_request *rreq); 79 ssize_t netfs_wait_for_write(struct netfs_io_request *rreq); 80 void netfs_wait_for_paused_read(struct netfs_io_request *rreq); 81 void netfs_wait_for_paused_write(struct netfs_io_request *rreq); 82 83 /* 84 * objects.c 85 */ 86 struct netfs_io_request *netfs_alloc_request(struct address_space *mapping, 87 struct file *file, 88 loff_t start, size_t len, 89 enum netfs_io_origin origin); 90 void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what); 91 void netfs_clear_subrequests(struct netfs_io_request *rreq); 92 void netfs_put_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what); 93 void netfs_put_failed_request(struct netfs_io_request *rreq); 94 struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq); 95 96 static inline void netfs_see_request(struct netfs_io_request *rreq, 97 enum netfs_rreq_ref_trace what) 98 { 99 trace_netfs_rreq_ref(rreq->debug_id, refcount_read(&rreq->ref), what); 100 } 101 102 static inline void netfs_see_subrequest(struct netfs_io_subrequest *subreq, 103 enum netfs_sreq_ref_trace what) 104 { 105 trace_netfs_sreq_ref(subreq->rreq->debug_id, subreq->debug_index, 106 refcount_read(&subreq->ref), what); 107 } 108 109 /* 110 * read_collect.c 111 */ 112 bool netfs_read_collection(struct netfs_io_request *rreq); 113 void netfs_read_collection_worker(struct work_struct *work); 114 void netfs_cancel_read(struct netfs_io_subrequest *subreq, int error); 115 void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error); 116 117 /* 118 * read_pgpriv2.c 119 */ 120 void netfs_pgpriv2_copy_to_cache(struct netfs_io_request *rreq, struct folio *folio); 121 void netfs_pgpriv2_end_copy_to_cache(struct netfs_io_request *rreq); 122 bool netfs_pgpriv2_unlock_copied_folios(struct netfs_io_request *wreq); 123 124 /* 125 * read_retry.c 126 */ 127 void netfs_retry_reads(struct netfs_io_request *rreq); 128 void netfs_unlock_abandoned_read_pages(struct netfs_io_request *rreq); 129 130 /* 131 * stats.c 132 */ 133 #ifdef CONFIG_NETFS_STATS 134 extern atomic_t netfs_n_rh_dio_read; 135 extern atomic_t netfs_n_rh_readahead; 136 extern atomic_t netfs_n_rh_read_folio; 137 extern atomic_t netfs_n_rh_read_single; 138 extern atomic_t netfs_n_rh_rreq; 139 extern atomic_t netfs_n_rh_sreq; 140 extern atomic_t netfs_n_rh_download; 141 extern atomic_t netfs_n_rh_download_done; 142 extern atomic_t netfs_n_rh_download_failed; 143 extern atomic_t netfs_n_rh_download_instead; 144 extern atomic_t netfs_n_rh_read; 145 extern atomic_t netfs_n_rh_read_done; 146 extern atomic_t netfs_n_rh_read_failed; 147 extern atomic_t netfs_n_rh_zero; 148 extern atomic_t netfs_n_rh_short_read; 149 extern atomic_t netfs_n_rh_write; 150 extern atomic_t netfs_n_rh_write_begin; 151 extern atomic_t netfs_n_rh_write_done; 152 extern atomic_t netfs_n_rh_write_failed; 153 extern atomic_t netfs_n_rh_write_zskip; 154 extern atomic_t netfs_n_rh_retry_read_req; 155 extern atomic_t netfs_n_rh_retry_read_subreq; 156 extern atomic_t netfs_n_wh_buffered_write; 157 extern atomic_t netfs_n_wh_writethrough; 158 extern atomic_t netfs_n_wh_dio_write; 159 extern atomic_t netfs_n_wh_writepages; 160 extern atomic_t netfs_n_wh_copy_to_cache; 161 extern atomic_t netfs_n_wh_wstream_conflict; 162 extern atomic_t netfs_n_wh_upload; 163 extern atomic_t netfs_n_wh_upload_done; 164 extern atomic_t netfs_n_wh_upload_failed; 165 extern atomic_t netfs_n_wh_write; 166 extern atomic_t netfs_n_wh_write_done; 167 extern atomic_t netfs_n_wh_write_failed; 168 extern atomic_t netfs_n_wh_retry_write_req; 169 extern atomic_t netfs_n_wh_retry_write_subreq; 170 extern atomic_t netfs_n_wb_lock_skip; 171 extern atomic_t netfs_n_wb_lock_wait; 172 extern atomic_t netfs_n_folioq; 173 174 int netfs_stats_show(struct seq_file *m, void *v); 175 176 static inline void netfs_stat(atomic_t *stat) 177 { 178 atomic_inc(stat); 179 } 180 181 static inline void netfs_stat_d(atomic_t *stat) 182 { 183 atomic_dec(stat); 184 } 185 186 #else 187 #define netfs_stat(x) do {} while(0) 188 #define netfs_stat_d(x) do {} while(0) 189 #endif 190 191 /* 192 * write_collect.c 193 */ 194 int netfs_folio_written_back(struct folio *folio); 195 bool netfs_write_collection(struct netfs_io_request *wreq); 196 void netfs_write_collection_worker(struct work_struct *work); 197 198 /* 199 * write_issue.c 200 */ 201 struct netfs_io_request *netfs_create_write_req(struct address_space *mapping, 202 struct file *file, 203 loff_t start, 204 enum netfs_io_origin origin); 205 void netfs_prepare_write(struct netfs_io_request *wreq, 206 struct netfs_io_stream *stream, 207 loff_t start); 208 void netfs_reissue_write(struct netfs_io_stream *stream, 209 struct netfs_io_subrequest *subreq, 210 struct iov_iter *source); 211 void netfs_issue_write(struct netfs_io_request *wreq, 212 struct netfs_io_stream *stream); 213 size_t netfs_advance_write(struct netfs_io_request *wreq, 214 struct netfs_io_stream *stream, 215 loff_t start, size_t len, bool to_eof); 216 struct netfs_io_request *netfs_begin_writethrough(struct kiocb *iocb, size_t len); 217 int netfs_advance_writethrough(struct netfs_io_request *wreq, struct writeback_control *wbc, 218 struct folio *folio, size_t copied, bool to_page_end, 219 struct folio **writethrough_cache); 220 ssize_t netfs_end_writethrough(struct netfs_io_request *wreq, struct writeback_control *wbc, 221 struct folio *writethrough_cache); 222 223 /* 224 * write_retry.c 225 */ 226 void netfs_retry_writes(struct netfs_io_request *wreq); 227 228 /* 229 * Miscellaneous functions. 230 */ 231 static inline bool netfs_is_cache_enabled(struct netfs_inode *ctx) 232 { 233 #if IS_ENABLED(CONFIG_FSCACHE) 234 struct fscache_cookie *cookie = ctx->cache; 235 236 return fscache_cookie_valid(cookie) && cookie->cache_priv && 237 fscache_cookie_enabled(cookie); 238 #else 239 return false; 240 #endif 241 } 242 243 static inline bool netfs_is_cache_maybe_enabled(struct netfs_inode *ctx) 244 { 245 #if IS_ENABLED(CONFIG_FSCACHE) 246 struct fscache_cookie *cookie = ctx->cache; 247 248 return fscache_cookie_valid(cookie) && 249 test_bit(FSCACHE_COOKIE_IS_CACHING, &cookie->flags); 250 #else 251 return false; 252 #endif 253 } 254 255 /* 256 * Get a ref on a netfs group attached to a dirty page (e.g. a ceph snap). 257 */ 258 static inline struct netfs_group *netfs_get_group(struct netfs_group *netfs_group) 259 { 260 if (netfs_group && netfs_group != NETFS_FOLIO_COPY_TO_CACHE) 261 refcount_inc(&netfs_group->ref); 262 return netfs_group; 263 } 264 265 /* 266 * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap). 267 */ 268 static inline void netfs_put_group(struct netfs_group *netfs_group) 269 { 270 if (netfs_group && 271 netfs_group != NETFS_FOLIO_COPY_TO_CACHE && 272 refcount_dec_and_test(&netfs_group->ref)) 273 netfs_group->free(netfs_group); 274 } 275 276 /* 277 * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap). 278 */ 279 static inline void netfs_put_group_many(struct netfs_group *netfs_group, int nr) 280 { 281 if (netfs_group && 282 netfs_group != NETFS_FOLIO_COPY_TO_CACHE && 283 refcount_sub_and_test(nr, &netfs_group->ref)) 284 netfs_group->free(netfs_group); 285 } 286 287 /* 288 * Clear and wake up a NETFS_RREQ_* flag bit on a request. 289 */ 290 static inline void netfs_wake_rreq_flag(struct netfs_io_request *rreq, 291 unsigned int rreq_flag, 292 enum netfs_rreq_trace trace) 293 { 294 if (test_bit(rreq_flag, &rreq->flags)) { 295 clear_bit_unlock(rreq_flag, &rreq->flags); 296 smp_mb__after_atomic(); /* Set flag before task state */ 297 trace_netfs_rreq(rreq, trace); 298 wake_up(&rreq->waitq); 299 } 300 } 301 302 /* 303 * Test the NETFS_RREQ_IN_PROGRESS flag, inserting an appropriate barrier. 304 */ 305 static inline bool netfs_check_rreq_in_progress(const struct netfs_io_request *rreq) 306 { 307 /* Order read of flags before read of anything else, such as error. */ 308 return test_bit_acquire(NETFS_RREQ_IN_PROGRESS, &rreq->flags); 309 } 310 311 /* 312 * Test the NETFS_SREQ_IN_PROGRESS flag, inserting an appropriate barrier. 313 */ 314 static inline bool netfs_check_subreq_in_progress(const struct netfs_io_subrequest *subreq) 315 { 316 /* Order read of flags before read of anything else, such as error. */ 317 return test_bit_acquire(NETFS_SREQ_IN_PROGRESS, &subreq->flags); 318 } 319 320 /* 321 * fscache-cache.c 322 */ 323 #ifdef CONFIG_PROC_FS 324 extern const struct seq_operations fscache_caches_seq_ops; 325 #endif 326 bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why); 327 void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why); 328 struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache); 329 void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where); 330 331 static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache) 332 { 333 return smp_load_acquire(&cache->state); 334 } 335 336 static inline bool fscache_cache_is_live(const struct fscache_cache *cache) 337 { 338 return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE; 339 } 340 341 static inline void fscache_set_cache_state(struct fscache_cache *cache, 342 enum fscache_cache_state new_state) 343 { 344 smp_store_release(&cache->state, new_state); 345 346 } 347 348 static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache, 349 enum fscache_cache_state old_state, 350 enum fscache_cache_state new_state) 351 { 352 return try_cmpxchg_release(&cache->state, &old_state, new_state); 353 } 354 355 /* 356 * fscache-cookie.c 357 */ 358 extern struct kmem_cache *fscache_cookie_jar; 359 #ifdef CONFIG_PROC_FS 360 extern const struct seq_operations fscache_cookies_seq_ops; 361 #endif 362 extern struct timer_list fscache_cookie_lru_timer; 363 364 extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix); 365 extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie, 366 enum fscache_access_trace why); 367 368 static inline void fscache_see_cookie(struct fscache_cookie *cookie, 369 enum fscache_cookie_trace where) 370 { 371 trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref), 372 where); 373 } 374 375 /* 376 * fscache-main.c 377 */ 378 extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len); 379 #ifdef CONFIG_FSCACHE 380 int __init fscache_init(void); 381 void __exit fscache_exit(void); 382 #else 383 static inline int fscache_init(void) { return 0; } 384 static inline void fscache_exit(void) {} 385 #endif 386 387 /* 388 * fscache-proc.c 389 */ 390 #ifdef CONFIG_PROC_FS 391 extern int __init fscache_proc_init(void); 392 extern void fscache_proc_cleanup(void); 393 #else 394 #define fscache_proc_init() (0) 395 #define fscache_proc_cleanup() do {} while (0) 396 #endif 397 398 /* 399 * fscache-stats.c 400 */ 401 #ifdef CONFIG_FSCACHE_STATS 402 extern atomic_t fscache_n_volumes; 403 extern atomic_t fscache_n_volumes_collision; 404 extern atomic_t fscache_n_volumes_nomem; 405 extern atomic_t fscache_n_cookies; 406 extern atomic_t fscache_n_cookies_lru; 407 extern atomic_t fscache_n_cookies_lru_expired; 408 extern atomic_t fscache_n_cookies_lru_removed; 409 extern atomic_t fscache_n_cookies_lru_dropped; 410 411 extern atomic_t fscache_n_acquires; 412 extern atomic_t fscache_n_acquires_ok; 413 extern atomic_t fscache_n_acquires_oom; 414 415 extern atomic_t fscache_n_invalidates; 416 417 extern atomic_t fscache_n_relinquishes; 418 extern atomic_t fscache_n_relinquishes_retire; 419 extern atomic_t fscache_n_relinquishes_dropped; 420 421 extern atomic_t fscache_n_resizes; 422 extern atomic_t fscache_n_resizes_null; 423 424 static inline void fscache_stat(atomic_t *stat) 425 { 426 atomic_inc(stat); 427 } 428 429 static inline void fscache_stat_d(atomic_t *stat) 430 { 431 atomic_dec(stat); 432 } 433 434 #define __fscache_stat(stat) (stat) 435 436 int fscache_stats_show(struct seq_file *m); 437 #else 438 439 #define __fscache_stat(stat) (NULL) 440 #define fscache_stat(stat) do {} while (0) 441 #define fscache_stat_d(stat) do {} while (0) 442 443 static inline int fscache_stats_show(struct seq_file *m) { return 0; } 444 #endif 445 446 /* 447 * fscache-volume.c 448 */ 449 #ifdef CONFIG_PROC_FS 450 extern const struct seq_operations fscache_volumes_seq_ops; 451 #endif 452 453 struct fscache_volume *fscache_get_volume(struct fscache_volume *volume, 454 enum fscache_volume_trace where); 455 bool fscache_begin_volume_access(struct fscache_volume *volume, 456 struct fscache_cookie *cookie, 457 enum fscache_access_trace why); 458 void fscache_create_volume(struct fscache_volume *volume, bool wait); 459 460 /*****************************************************************************/ 461 /* 462 * debug tracing 463 */ 464 #define dbgprintk(FMT, ...) \ 465 printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__) 466 467 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__) 468 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 469 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__) 470 471 #ifdef __KDEBUG 472 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__) 473 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__) 474 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__) 475 476 #elif defined(CONFIG_NETFS_DEBUG) 477 #define _enter(FMT, ...) \ 478 do { \ 479 if (netfs_debug) \ 480 kenter(FMT, ##__VA_ARGS__); \ 481 } while (0) 482 483 #define _leave(FMT, ...) \ 484 do { \ 485 if (netfs_debug) \ 486 kleave(FMT, ##__VA_ARGS__); \ 487 } while (0) 488 489 #define _debug(FMT, ...) \ 490 do { \ 491 if (netfs_debug) \ 492 kdebug(FMT, ##__VA_ARGS__); \ 493 } while (0) 494 495 #else 496 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__) 497 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__) 498 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__) 499 #endif 500 501 /* 502 * assertions 503 */ 504 #if 1 /* defined(__KDEBUGALL) */ 505 506 #define ASSERT(X) \ 507 do { \ 508 if (unlikely(!(X))) { \ 509 pr_err("\n"); \ 510 pr_err("Assertion failed\n"); \ 511 BUG(); \ 512 } \ 513 } while (0) 514 515 #define ASSERTCMP(X, OP, Y) \ 516 do { \ 517 if (unlikely(!((X) OP (Y)))) { \ 518 pr_err("\n"); \ 519 pr_err("Assertion failed\n"); \ 520 pr_err("%lx " #OP " %lx is false\n", \ 521 (unsigned long)(X), (unsigned long)(Y)); \ 522 BUG(); \ 523 } \ 524 } while (0) 525 526 #define ASSERTIF(C, X) \ 527 do { \ 528 if (unlikely((C) && !(X))) { \ 529 pr_err("\n"); \ 530 pr_err("Assertion failed\n"); \ 531 BUG(); \ 532 } \ 533 } while (0) 534 535 #define ASSERTIFCMP(C, X, OP, Y) \ 536 do { \ 537 if (unlikely((C) && !((X) OP (Y)))) { \ 538 pr_err("\n"); \ 539 pr_err("Assertion failed\n"); \ 540 pr_err("%lx " #OP " %lx is false\n", \ 541 (unsigned long)(X), (unsigned long)(Y)); \ 542 BUG(); \ 543 } \ 544 } while (0) 545 546 #else 547 548 #define ASSERT(X) do {} while (0) 549 #define ASSERTCMP(X, OP, Y) do {} while (0) 550 #define ASSERTIF(C, X) do {} while (0) 551 #define ASSERTIFCMP(C, X, OP, Y) do {} while (0) 552 553 #endif /* assert or not */ 554