cache.c revision cd68c374ea9ce202ae7c6346777d10078e243d49
1/* 2 * net/sunrpc/cache.c 3 * 4 * Generic code for various authentication-related caches 5 * used by sunrpc clients and servers. 6 * 7 * Copyright (C) 2002 Neil Brown <neilb@cse.unsw.edu.au> 8 * 9 * Released under terms in GPL version 2. See COPYING. 10 * 11 */ 12 13#include <linux/types.h> 14#include <linux/fs.h> 15#include <linux/file.h> 16#include <linux/slab.h> 17#include <linux/signal.h> 18#include <linux/sched.h> 19#include <linux/kmod.h> 20#include <linux/list.h> 21#include <linux/module.h> 22#include <linux/ctype.h> 23#include <asm/uaccess.h> 24#include <linux/poll.h> 25#include <linux/seq_file.h> 26#include <linux/proc_fs.h> 27#include <linux/net.h> 28#include <linux/workqueue.h> 29#include <linux/mutex.h> 30#include <linux/pagemap.h> 31#include <asm/ioctls.h> 32#include <linux/sunrpc/types.h> 33#include <linux/sunrpc/cache.h> 34#include <linux/sunrpc/stats.h> 35#include <linux/sunrpc/rpc_pipe_fs.h> 36 37#define RPCDBG_FACILITY RPCDBG_CACHE 38 39static int cache_defer_req(struct cache_req *req, struct cache_head *item); 40static void cache_revisit_request(struct cache_head *item); 41 42static void cache_init(struct cache_head *h) 43{ 44 time_t now = get_seconds(); 45 h->next = NULL; 46 h->flags = 0; 47 kref_init(&h->ref); 48 h->expiry_time = now + CACHE_NEW_EXPIRY; 49 h->last_refresh = now; 50} 51 52struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail, 53 struct cache_head *key, int hash) 54{ 55 struct cache_head **head, **hp; 56 struct cache_head *new = NULL; 57 58 head = &detail->hash_table[hash]; 59 60 read_lock(&detail->hash_lock); 61 62 for (hp=head; *hp != NULL ; hp = &(*hp)->next) { 63 struct cache_head *tmp = *hp; 64 if (detail->match(tmp, key)) { 65 cache_get(tmp); 66 read_unlock(&detail->hash_lock); 67 return tmp; 68 } 69 } 70 read_unlock(&detail->hash_lock); 71 /* Didn't find anything, insert an empty entry */ 72 73 new = detail->alloc(); 74 if (!new) 75 return NULL; 76 /* must fully initialise 'new', else 77 * we might get lose if we need to 78 * cache_put it soon. 79 */ 80 cache_init(new); 81 detail->init(new, key); 82 83 write_lock(&detail->hash_lock); 84 85 /* check if entry appeared while we slept */ 86 for (hp=head; *hp != NULL ; hp = &(*hp)->next) { 87 struct cache_head *tmp = *hp; 88 if (detail->match(tmp, key)) { 89 cache_get(tmp); 90 write_unlock(&detail->hash_lock); 91 cache_put(new, detail); 92 return tmp; 93 } 94 } 95 new->next = *head; 96 *head = new; 97 detail->entries++; 98 cache_get(new); 99 write_unlock(&detail->hash_lock); 100 101 return new; 102} 103EXPORT_SYMBOL_GPL(sunrpc_cache_lookup); 104 105 106static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch); 107 108static void cache_fresh_locked(struct cache_head *head, time_t expiry) 109{ 110 head->expiry_time = expiry; 111 head->last_refresh = get_seconds(); 112 set_bit(CACHE_VALID, &head->flags); 113} 114 115static void cache_fresh_unlocked(struct cache_head *head, 116 struct cache_detail *detail) 117{ 118 if (test_and_clear_bit(CACHE_PENDING, &head->flags)) { 119 cache_revisit_request(head); 120 cache_dequeue(detail, head); 121 } 122} 123 124struct cache_head *sunrpc_cache_update(struct cache_detail *detail, 125 struct cache_head *new, struct cache_head *old, int hash) 126{ 127 /* The 'old' entry is to be replaced by 'new'. 128 * If 'old' is not VALID, we update it directly, 129 * otherwise we need to replace it 130 */ 131 struct cache_head **head; 132 struct cache_head *tmp; 133 134 if (!test_bit(CACHE_VALID, &old->flags)) { 135 write_lock(&detail->hash_lock); 136 if (!test_bit(CACHE_VALID, &old->flags)) { 137 if (test_bit(CACHE_NEGATIVE, &new->flags)) 138 set_bit(CACHE_NEGATIVE, &old->flags); 139 else 140 detail->update(old, new); 141 cache_fresh_locked(old, new->expiry_time); 142 write_unlock(&detail->hash_lock); 143 cache_fresh_unlocked(old, detail); 144 return old; 145 } 146 write_unlock(&detail->hash_lock); 147 } 148 /* We need to insert a new entry */ 149 tmp = detail->alloc(); 150 if (!tmp) { 151 cache_put(old, detail); 152 return NULL; 153 } 154 cache_init(tmp); 155 detail->init(tmp, old); 156 head = &detail->hash_table[hash]; 157 158 write_lock(&detail->hash_lock); 159 if (test_bit(CACHE_NEGATIVE, &new->flags)) 160 set_bit(CACHE_NEGATIVE, &tmp->flags); 161 else 162 detail->update(tmp, new); 163 tmp->next = *head; 164 *head = tmp; 165 detail->entries++; 166 cache_get(tmp); 167 cache_fresh_locked(tmp, new->expiry_time); 168 cache_fresh_locked(old, 0); 169 write_unlock(&detail->hash_lock); 170 cache_fresh_unlocked(tmp, detail); 171 cache_fresh_unlocked(old, detail); 172 cache_put(old, detail); 173 return tmp; 174} 175EXPORT_SYMBOL_GPL(sunrpc_cache_update); 176 177static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h) 178{ 179 if (!cd->cache_upcall) 180 return -EINVAL; 181 return cd->cache_upcall(cd, h); 182} 183 184static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h) 185{ 186 if (!test_bit(CACHE_VALID, &h->flags) || 187 h->expiry_time < get_seconds()) 188 return -EAGAIN; 189 else if (detail->flush_time > h->last_refresh) 190 return -EAGAIN; 191 else { 192 /* entry is valid */ 193 if (test_bit(CACHE_NEGATIVE, &h->flags)) 194 return -ENOENT; 195 else 196 return 0; 197 } 198} 199 200/* 201 * This is the generic cache management routine for all 202 * the authentication caches. 203 * It checks the currency of a cache item and will (later) 204 * initiate an upcall to fill it if needed. 205 * 206 * 207 * Returns 0 if the cache_head can be used, or cache_puts it and returns 208 * -EAGAIN if upcall is pending and request has been queued 209 * -ETIMEDOUT if upcall failed or request could not be queue or 210 * upcall completed but item is still invalid (implying that 211 * the cache item has been replaced with a newer one). 212 * -ENOENT if cache entry was negative 213 */ 214int cache_check(struct cache_detail *detail, 215 struct cache_head *h, struct cache_req *rqstp) 216{ 217 int rv; 218 long refresh_age, age; 219 220 /* First decide return status as best we can */ 221 rv = cache_is_valid(detail, h); 222 223 /* now see if we want to start an upcall */ 224 refresh_age = (h->expiry_time - h->last_refresh); 225 age = get_seconds() - h->last_refresh; 226 227 if (rqstp == NULL) { 228 if (rv == -EAGAIN) 229 rv = -ENOENT; 230 } else if (rv == -EAGAIN || age > refresh_age/2) { 231 dprintk("RPC: Want update, refage=%ld, age=%ld\n", 232 refresh_age, age); 233 if (!test_and_set_bit(CACHE_PENDING, &h->flags)) { 234 switch (cache_make_upcall(detail, h)) { 235 case -EINVAL: 236 clear_bit(CACHE_PENDING, &h->flags); 237 cache_revisit_request(h); 238 if (rv == -EAGAIN) { 239 set_bit(CACHE_NEGATIVE, &h->flags); 240 cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY); 241 cache_fresh_unlocked(h, detail); 242 rv = -ENOENT; 243 } 244 break; 245 246 case -EAGAIN: 247 clear_bit(CACHE_PENDING, &h->flags); 248 cache_revisit_request(h); 249 break; 250 } 251 } 252 } 253 254 if (rv == -EAGAIN) { 255 if (cache_defer_req(rqstp, h) < 0) { 256 /* Request is not deferred */ 257 rv = cache_is_valid(detail, h); 258 if (rv == -EAGAIN) 259 rv = -ETIMEDOUT; 260 } 261 } 262 if (rv) 263 cache_put(h, detail); 264 return rv; 265} 266EXPORT_SYMBOL_GPL(cache_check); 267 268/* 269 * caches need to be periodically cleaned. 270 * For this we maintain a list of cache_detail and 271 * a current pointer into that list and into the table 272 * for that entry. 273 * 274 * Each time clean_cache is called it finds the next non-empty entry 275 * in the current table and walks the list in that entry 276 * looking for entries that can be removed. 277 * 278 * An entry gets removed if: 279 * - The expiry is before current time 280 * - The last_refresh time is before the flush_time for that cache 281 * 282 * later we might drop old entries with non-NEVER expiry if that table 283 * is getting 'full' for some definition of 'full' 284 * 285 * The question of "how often to scan a table" is an interesting one 286 * and is answered in part by the use of the "nextcheck" field in the 287 * cache_detail. 288 * When a scan of a table begins, the nextcheck field is set to a time 289 * that is well into the future. 290 * While scanning, if an expiry time is found that is earlier than the 291 * current nextcheck time, nextcheck is set to that expiry time. 292 * If the flush_time is ever set to a time earlier than the nextcheck 293 * time, the nextcheck time is then set to that flush_time. 294 * 295 * A table is then only scanned if the current time is at least 296 * the nextcheck time. 297 * 298 */ 299 300static LIST_HEAD(cache_list); 301static DEFINE_SPINLOCK(cache_list_lock); 302static struct cache_detail *current_detail; 303static int current_index; 304 305static void do_cache_clean(struct work_struct *work); 306static DECLARE_DELAYED_WORK(cache_cleaner, do_cache_clean); 307 308static void sunrpc_init_cache_detail(struct cache_detail *cd) 309{ 310 rwlock_init(&cd->hash_lock); 311 INIT_LIST_HEAD(&cd->queue); 312 spin_lock(&cache_list_lock); 313 cd->nextcheck = 0; 314 cd->entries = 0; 315 atomic_set(&cd->readers, 0); 316 cd->last_close = 0; 317 cd->last_warn = -1; 318 list_add(&cd->others, &cache_list); 319 spin_unlock(&cache_list_lock); 320 321 /* start the cleaning process */ 322 schedule_delayed_work(&cache_cleaner, 0); 323} 324 325static void sunrpc_destroy_cache_detail(struct cache_detail *cd) 326{ 327 cache_purge(cd); 328 spin_lock(&cache_list_lock); 329 write_lock(&cd->hash_lock); 330 if (cd->entries || atomic_read(&cd->inuse)) { 331 write_unlock(&cd->hash_lock); 332 spin_unlock(&cache_list_lock); 333 goto out; 334 } 335 if (current_detail == cd) 336 current_detail = NULL; 337 list_del_init(&cd->others); 338 write_unlock(&cd->hash_lock); 339 spin_unlock(&cache_list_lock); 340 if (list_empty(&cache_list)) { 341 /* module must be being unloaded so its safe to kill the worker */ 342 cancel_delayed_work_sync(&cache_cleaner); 343 } 344 return; 345out: 346 printk(KERN_ERR "nfsd: failed to unregister %s cache\n", cd->name); 347} 348 349/* clean cache tries to find something to clean 350 * and cleans it. 351 * It returns 1 if it cleaned something, 352 * 0 if it didn't find anything this time 353 * -1 if it fell off the end of the list. 354 */ 355static int cache_clean(void) 356{ 357 int rv = 0; 358 struct list_head *next; 359 360 spin_lock(&cache_list_lock); 361 362 /* find a suitable table if we don't already have one */ 363 while (current_detail == NULL || 364 current_index >= current_detail->hash_size) { 365 if (current_detail) 366 next = current_detail->others.next; 367 else 368 next = cache_list.next; 369 if (next == &cache_list) { 370 current_detail = NULL; 371 spin_unlock(&cache_list_lock); 372 return -1; 373 } 374 current_detail = list_entry(next, struct cache_detail, others); 375 if (current_detail->nextcheck > get_seconds()) 376 current_index = current_detail->hash_size; 377 else { 378 current_index = 0; 379 current_detail->nextcheck = get_seconds()+30*60; 380 } 381 } 382 383 /* find a non-empty bucket in the table */ 384 while (current_detail && 385 current_index < current_detail->hash_size && 386 current_detail->hash_table[current_index] == NULL) 387 current_index++; 388 389 /* find a cleanable entry in the bucket and clean it, or set to next bucket */ 390 391 if (current_detail && current_index < current_detail->hash_size) { 392 struct cache_head *ch, **cp; 393 struct cache_detail *d; 394 395 write_lock(¤t_detail->hash_lock); 396 397 /* Ok, now to clean this strand */ 398 399 cp = & current_detail->hash_table[current_index]; 400 ch = *cp; 401 for (; ch; cp= & ch->next, ch= *cp) { 402 if (current_detail->nextcheck > ch->expiry_time) 403 current_detail->nextcheck = ch->expiry_time+1; 404 if (ch->expiry_time >= get_seconds() 405 && ch->last_refresh >= current_detail->flush_time 406 ) 407 continue; 408 if (test_and_clear_bit(CACHE_PENDING, &ch->flags)) 409 cache_dequeue(current_detail, ch); 410 411 if (atomic_read(&ch->ref.refcount) == 1) 412 break; 413 } 414 if (ch) { 415 *cp = ch->next; 416 ch->next = NULL; 417 current_detail->entries--; 418 rv = 1; 419 } 420 write_unlock(¤t_detail->hash_lock); 421 d = current_detail; 422 if (!ch) 423 current_index ++; 424 spin_unlock(&cache_list_lock); 425 if (ch) { 426 cache_revisit_request(ch); 427 cache_put(ch, d); 428 } 429 } else 430 spin_unlock(&cache_list_lock); 431 432 return rv; 433} 434 435/* 436 * We want to regularly clean the cache, so we need to schedule some work ... 437 */ 438static void do_cache_clean(struct work_struct *work) 439{ 440 int delay = 5; 441 if (cache_clean() == -1) 442 delay = round_jiffies_relative(30*HZ); 443 444 if (list_empty(&cache_list)) 445 delay = 0; 446 447 if (delay) 448 schedule_delayed_work(&cache_cleaner, delay); 449} 450 451 452/* 453 * Clean all caches promptly. This just calls cache_clean 454 * repeatedly until we are sure that every cache has had a chance to 455 * be fully cleaned 456 */ 457void cache_flush(void) 458{ 459 while (cache_clean() != -1) 460 cond_resched(); 461 while (cache_clean() != -1) 462 cond_resched(); 463} 464EXPORT_SYMBOL_GPL(cache_flush); 465 466void cache_purge(struct cache_detail *detail) 467{ 468 detail->flush_time = LONG_MAX; 469 detail->nextcheck = get_seconds(); 470 cache_flush(); 471 detail->flush_time = 1; 472} 473EXPORT_SYMBOL_GPL(cache_purge); 474 475 476/* 477 * Deferral and Revisiting of Requests. 478 * 479 * If a cache lookup finds a pending entry, we 480 * need to defer the request and revisit it later. 481 * All deferred requests are stored in a hash table, 482 * indexed by "struct cache_head *". 483 * As it may be wasteful to store a whole request 484 * structure, we allow the request to provide a 485 * deferred form, which must contain a 486 * 'struct cache_deferred_req' 487 * This cache_deferred_req contains a method to allow 488 * it to be revisited when cache info is available 489 */ 490 491#define DFR_HASHSIZE (PAGE_SIZE/sizeof(struct list_head)) 492#define DFR_HASH(item) ((((long)item)>>4 ^ (((long)item)>>13)) % DFR_HASHSIZE) 493 494#define DFR_MAX 300 /* ??? */ 495 496static DEFINE_SPINLOCK(cache_defer_lock); 497static LIST_HEAD(cache_defer_list); 498static struct list_head cache_defer_hash[DFR_HASHSIZE]; 499static int cache_defer_cnt; 500 501static int cache_defer_req(struct cache_req *req, struct cache_head *item) 502{ 503 struct cache_deferred_req *dreq, *discard; 504 int hash = DFR_HASH(item); 505 506 if (cache_defer_cnt >= DFR_MAX) { 507 /* too much in the cache, randomly drop this one, 508 * or continue and drop the oldest below 509 */ 510 if (net_random()&1) 511 return -ENOMEM; 512 } 513 dreq = req->defer(req); 514 if (dreq == NULL) 515 return -ENOMEM; 516 517 dreq->item = item; 518 519 spin_lock(&cache_defer_lock); 520 521 list_add(&dreq->recent, &cache_defer_list); 522 523 if (cache_defer_hash[hash].next == NULL) 524 INIT_LIST_HEAD(&cache_defer_hash[hash]); 525 list_add(&dreq->hash, &cache_defer_hash[hash]); 526 527 /* it is in, now maybe clean up */ 528 discard = NULL; 529 if (++cache_defer_cnt > DFR_MAX) { 530 discard = list_entry(cache_defer_list.prev, 531 struct cache_deferred_req, recent); 532 list_del_init(&discard->recent); 533 list_del_init(&discard->hash); 534 cache_defer_cnt--; 535 } 536 spin_unlock(&cache_defer_lock); 537 538 if (discard) 539 /* there was one too many */ 540 discard->revisit(discard, 1); 541 542 if (!test_bit(CACHE_PENDING, &item->flags)) { 543 /* must have just been validated... */ 544 cache_revisit_request(item); 545 return -EAGAIN; 546 } 547 return 0; 548} 549 550static void cache_revisit_request(struct cache_head *item) 551{ 552 struct cache_deferred_req *dreq; 553 struct list_head pending; 554 555 struct list_head *lp; 556 int hash = DFR_HASH(item); 557 558 INIT_LIST_HEAD(&pending); 559 spin_lock(&cache_defer_lock); 560 561 lp = cache_defer_hash[hash].next; 562 if (lp) { 563 while (lp != &cache_defer_hash[hash]) { 564 dreq = list_entry(lp, struct cache_deferred_req, hash); 565 lp = lp->next; 566 if (dreq->item == item) { 567 list_del_init(&dreq->hash); 568 list_move(&dreq->recent, &pending); 569 cache_defer_cnt--; 570 } 571 } 572 } 573 spin_unlock(&cache_defer_lock); 574 575 while (!list_empty(&pending)) { 576 dreq = list_entry(pending.next, struct cache_deferred_req, recent); 577 list_del_init(&dreq->recent); 578 dreq->revisit(dreq, 0); 579 } 580} 581 582void cache_clean_deferred(void *owner) 583{ 584 struct cache_deferred_req *dreq, *tmp; 585 struct list_head pending; 586 587 588 INIT_LIST_HEAD(&pending); 589 spin_lock(&cache_defer_lock); 590 591 list_for_each_entry_safe(dreq, tmp, &cache_defer_list, recent) { 592 if (dreq->owner == owner) { 593 list_del_init(&dreq->hash); 594 list_move(&dreq->recent, &pending); 595 cache_defer_cnt--; 596 } 597 } 598 spin_unlock(&cache_defer_lock); 599 600 while (!list_empty(&pending)) { 601 dreq = list_entry(pending.next, struct cache_deferred_req, recent); 602 list_del_init(&dreq->recent); 603 dreq->revisit(dreq, 1); 604 } 605} 606 607/* 608 * communicate with user-space 609 * 610 * We have a magic /proc file - /proc/sunrpc/<cachename>/channel. 611 * On read, you get a full request, or block. 612 * On write, an update request is processed. 613 * Poll works if anything to read, and always allows write. 614 * 615 * Implemented by linked list of requests. Each open file has 616 * a ->private that also exists in this list. New requests are added 617 * to the end and may wakeup and preceding readers. 618 * New readers are added to the head. If, on read, an item is found with 619 * CACHE_UPCALLING clear, we free it from the list. 620 * 621 */ 622 623static DEFINE_SPINLOCK(queue_lock); 624static DEFINE_MUTEX(queue_io_mutex); 625 626struct cache_queue { 627 struct list_head list; 628 int reader; /* if 0, then request */ 629}; 630struct cache_request { 631 struct cache_queue q; 632 struct cache_head *item; 633 char * buf; 634 int len; 635 int readers; 636}; 637struct cache_reader { 638 struct cache_queue q; 639 int offset; /* if non-0, we have a refcnt on next request */ 640}; 641 642static ssize_t cache_read(struct file *filp, char __user *buf, size_t count, 643 loff_t *ppos, struct cache_detail *cd) 644{ 645 struct cache_reader *rp = filp->private_data; 646 struct cache_request *rq; 647 struct inode *inode = filp->f_path.dentry->d_inode; 648 int err; 649 650 if (count == 0) 651 return 0; 652 653 mutex_lock(&inode->i_mutex); /* protect against multiple concurrent 654 * readers on this file */ 655 again: 656 spin_lock(&queue_lock); 657 /* need to find next request */ 658 while (rp->q.list.next != &cd->queue && 659 list_entry(rp->q.list.next, struct cache_queue, list) 660 ->reader) { 661 struct list_head *next = rp->q.list.next; 662 list_move(&rp->q.list, next); 663 } 664 if (rp->q.list.next == &cd->queue) { 665 spin_unlock(&queue_lock); 666 mutex_unlock(&inode->i_mutex); 667 BUG_ON(rp->offset); 668 return 0; 669 } 670 rq = container_of(rp->q.list.next, struct cache_request, q.list); 671 BUG_ON(rq->q.reader); 672 if (rp->offset == 0) 673 rq->readers++; 674 spin_unlock(&queue_lock); 675 676 if (rp->offset == 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) { 677 err = -EAGAIN; 678 spin_lock(&queue_lock); 679 list_move(&rp->q.list, &rq->q.list); 680 spin_unlock(&queue_lock); 681 } else { 682 if (rp->offset + count > rq->len) 683 count = rq->len - rp->offset; 684 err = -EFAULT; 685 if (copy_to_user(buf, rq->buf + rp->offset, count)) 686 goto out; 687 rp->offset += count; 688 if (rp->offset >= rq->len) { 689 rp->offset = 0; 690 spin_lock(&queue_lock); 691 list_move(&rp->q.list, &rq->q.list); 692 spin_unlock(&queue_lock); 693 } 694 err = 0; 695 } 696 out: 697 if (rp->offset == 0) { 698 /* need to release rq */ 699 spin_lock(&queue_lock); 700 rq->readers--; 701 if (rq->readers == 0 && 702 !test_bit(CACHE_PENDING, &rq->item->flags)) { 703 list_del(&rq->q.list); 704 spin_unlock(&queue_lock); 705 cache_put(rq->item, cd); 706 kfree(rq->buf); 707 kfree(rq); 708 } else 709 spin_unlock(&queue_lock); 710 } 711 if (err == -EAGAIN) 712 goto again; 713 mutex_unlock(&inode->i_mutex); 714 return err ? err : count; 715} 716 717static ssize_t cache_do_downcall(char *kaddr, const char __user *buf, 718 size_t count, struct cache_detail *cd) 719{ 720 ssize_t ret; 721 722 if (copy_from_user(kaddr, buf, count)) 723 return -EFAULT; 724 kaddr[count] = '\0'; 725 ret = cd->cache_parse(cd, kaddr, count); 726 if (!ret) 727 ret = count; 728 return ret; 729} 730 731static ssize_t cache_slow_downcall(const char __user *buf, 732 size_t count, struct cache_detail *cd) 733{ 734 static char write_buf[8192]; /* protected by queue_io_mutex */ 735 ssize_t ret = -EINVAL; 736 737 if (count >= sizeof(write_buf)) 738 goto out; 739 mutex_lock(&queue_io_mutex); 740 ret = cache_do_downcall(write_buf, buf, count, cd); 741 mutex_unlock(&queue_io_mutex); 742out: 743 return ret; 744} 745 746static ssize_t cache_downcall(struct address_space *mapping, 747 const char __user *buf, 748 size_t count, struct cache_detail *cd) 749{ 750 struct page *page; 751 char *kaddr; 752 ssize_t ret = -ENOMEM; 753 754 if (count >= PAGE_CACHE_SIZE) 755 goto out_slow; 756 757 page = find_or_create_page(mapping, 0, GFP_KERNEL); 758 if (!page) 759 goto out_slow; 760 761 kaddr = kmap(page); 762 ret = cache_do_downcall(kaddr, buf, count, cd); 763 kunmap(page); 764 unlock_page(page); 765 page_cache_release(page); 766 return ret; 767out_slow: 768 return cache_slow_downcall(buf, count, cd); 769} 770 771static ssize_t cache_write(struct file *filp, const char __user *buf, 772 size_t count, loff_t *ppos, 773 struct cache_detail *cd) 774{ 775 struct address_space *mapping = filp->f_mapping; 776 struct inode *inode = filp->f_path.dentry->d_inode; 777 ssize_t ret = -EINVAL; 778 779 if (!cd->cache_parse) 780 goto out; 781 782 mutex_lock(&inode->i_mutex); 783 ret = cache_downcall(mapping, buf, count, cd); 784 mutex_unlock(&inode->i_mutex); 785out: 786 return ret; 787} 788 789static DECLARE_WAIT_QUEUE_HEAD(queue_wait); 790 791static unsigned int cache_poll(struct file *filp, poll_table *wait, 792 struct cache_detail *cd) 793{ 794 unsigned int mask; 795 struct cache_reader *rp = filp->private_data; 796 struct cache_queue *cq; 797 798 poll_wait(filp, &queue_wait, wait); 799 800 /* alway allow write */ 801 mask = POLL_OUT | POLLWRNORM; 802 803 if (!rp) 804 return mask; 805 806 spin_lock(&queue_lock); 807 808 for (cq= &rp->q; &cq->list != &cd->queue; 809 cq = list_entry(cq->list.next, struct cache_queue, list)) 810 if (!cq->reader) { 811 mask |= POLLIN | POLLRDNORM; 812 break; 813 } 814 spin_unlock(&queue_lock); 815 return mask; 816} 817 818static int cache_ioctl(struct inode *ino, struct file *filp, 819 unsigned int cmd, unsigned long arg, 820 struct cache_detail *cd) 821{ 822 int len = 0; 823 struct cache_reader *rp = filp->private_data; 824 struct cache_queue *cq; 825 826 if (cmd != FIONREAD || !rp) 827 return -EINVAL; 828 829 spin_lock(&queue_lock); 830 831 /* only find the length remaining in current request, 832 * or the length of the next request 833 */ 834 for (cq= &rp->q; &cq->list != &cd->queue; 835 cq = list_entry(cq->list.next, struct cache_queue, list)) 836 if (!cq->reader) { 837 struct cache_request *cr = 838 container_of(cq, struct cache_request, q); 839 len = cr->len - rp->offset; 840 break; 841 } 842 spin_unlock(&queue_lock); 843 844 return put_user(len, (int __user *)arg); 845} 846 847static int cache_open(struct inode *inode, struct file *filp, 848 struct cache_detail *cd) 849{ 850 struct cache_reader *rp = NULL; 851 852 if (!cd || !try_module_get(cd->owner)) 853 return -EACCES; 854 nonseekable_open(inode, filp); 855 if (filp->f_mode & FMODE_READ) { 856 rp = kmalloc(sizeof(*rp), GFP_KERNEL); 857 if (!rp) 858 return -ENOMEM; 859 rp->offset = 0; 860 rp->q.reader = 1; 861 atomic_inc(&cd->readers); 862 spin_lock(&queue_lock); 863 list_add(&rp->q.list, &cd->queue); 864 spin_unlock(&queue_lock); 865 } 866 filp->private_data = rp; 867 return 0; 868} 869 870static int cache_release(struct inode *inode, struct file *filp, 871 struct cache_detail *cd) 872{ 873 struct cache_reader *rp = filp->private_data; 874 875 if (rp) { 876 spin_lock(&queue_lock); 877 if (rp->offset) { 878 struct cache_queue *cq; 879 for (cq= &rp->q; &cq->list != &cd->queue; 880 cq = list_entry(cq->list.next, struct cache_queue, list)) 881 if (!cq->reader) { 882 container_of(cq, struct cache_request, q) 883 ->readers--; 884 break; 885 } 886 rp->offset = 0; 887 } 888 list_del(&rp->q.list); 889 spin_unlock(&queue_lock); 890 891 filp->private_data = NULL; 892 kfree(rp); 893 894 cd->last_close = get_seconds(); 895 atomic_dec(&cd->readers); 896 } 897 module_put(cd->owner); 898 return 0; 899} 900 901 902 903static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch) 904{ 905 struct cache_queue *cq; 906 spin_lock(&queue_lock); 907 list_for_each_entry(cq, &detail->queue, list) 908 if (!cq->reader) { 909 struct cache_request *cr = container_of(cq, struct cache_request, q); 910 if (cr->item != ch) 911 continue; 912 if (cr->readers != 0) 913 continue; 914 list_del(&cr->q.list); 915 spin_unlock(&queue_lock); 916 cache_put(cr->item, detail); 917 kfree(cr->buf); 918 kfree(cr); 919 return; 920 } 921 spin_unlock(&queue_lock); 922} 923 924/* 925 * Support routines for text-based upcalls. 926 * Fields are separated by spaces. 927 * Fields are either mangled to quote space tab newline slosh with slosh 928 * or a hexified with a leading \x 929 * Record is terminated with newline. 930 * 931 */ 932 933void qword_add(char **bpp, int *lp, char *str) 934{ 935 char *bp = *bpp; 936 int len = *lp; 937 char c; 938 939 if (len < 0) return; 940 941 while ((c=*str++) && len) 942 switch(c) { 943 case ' ': 944 case '\t': 945 case '\n': 946 case '\\': 947 if (len >= 4) { 948 *bp++ = '\\'; 949 *bp++ = '0' + ((c & 0300)>>6); 950 *bp++ = '0' + ((c & 0070)>>3); 951 *bp++ = '0' + ((c & 0007)>>0); 952 } 953 len -= 4; 954 break; 955 default: 956 *bp++ = c; 957 len--; 958 } 959 if (c || len <1) len = -1; 960 else { 961 *bp++ = ' '; 962 len--; 963 } 964 *bpp = bp; 965 *lp = len; 966} 967EXPORT_SYMBOL_GPL(qword_add); 968 969void qword_addhex(char **bpp, int *lp, char *buf, int blen) 970{ 971 char *bp = *bpp; 972 int len = *lp; 973 974 if (len < 0) return; 975 976 if (len > 2) { 977 *bp++ = '\\'; 978 *bp++ = 'x'; 979 len -= 2; 980 while (blen && len >= 2) { 981 unsigned char c = *buf++; 982 *bp++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1); 983 *bp++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1); 984 len -= 2; 985 blen--; 986 } 987 } 988 if (blen || len<1) len = -1; 989 else { 990 *bp++ = ' '; 991 len--; 992 } 993 *bpp = bp; 994 *lp = len; 995} 996EXPORT_SYMBOL_GPL(qword_addhex); 997 998static void warn_no_listener(struct cache_detail *detail) 999{ 1000 if (detail->last_warn != detail->last_close) { 1001 detail->last_warn = detail->last_close; 1002 if (detail->warn_no_listener) 1003 detail->warn_no_listener(detail, detail->last_close != 0); 1004 } 1005} 1006 1007/* 1008 * register an upcall request to user-space and queue it up for read() by the 1009 * upcall daemon. 1010 * 1011 * Each request is at most one page long. 1012 */ 1013int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h, 1014 void (*cache_request)(struct cache_detail *, 1015 struct cache_head *, 1016 char **, 1017 int *)) 1018{ 1019 1020 char *buf; 1021 struct cache_request *crq; 1022 char *bp; 1023 int len; 1024 1025 if (atomic_read(&detail->readers) == 0 && 1026 detail->last_close < get_seconds() - 30) { 1027 warn_no_listener(detail); 1028 return -EINVAL; 1029 } 1030 1031 buf = kmalloc(PAGE_SIZE, GFP_KERNEL); 1032 if (!buf) 1033 return -EAGAIN; 1034 1035 crq = kmalloc(sizeof (*crq), GFP_KERNEL); 1036 if (!crq) { 1037 kfree(buf); 1038 return -EAGAIN; 1039 } 1040 1041 bp = buf; len = PAGE_SIZE; 1042 1043 cache_request(detail, h, &bp, &len); 1044 1045 if (len < 0) { 1046 kfree(buf); 1047 kfree(crq); 1048 return -EAGAIN; 1049 } 1050 crq->q.reader = 0; 1051 crq->item = cache_get(h); 1052 crq->buf = buf; 1053 crq->len = PAGE_SIZE - len; 1054 crq->readers = 0; 1055 spin_lock(&queue_lock); 1056 list_add_tail(&crq->q.list, &detail->queue); 1057 spin_unlock(&queue_lock); 1058 wake_up(&queue_wait); 1059 return 0; 1060} 1061EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall); 1062 1063/* 1064 * parse a message from user-space and pass it 1065 * to an appropriate cache 1066 * Messages are, like requests, separated into fields by 1067 * spaces and dequotes as \xHEXSTRING or embedded \nnn octal 1068 * 1069 * Message is 1070 * reply cachename expiry key ... content.... 1071 * 1072 * key and content are both parsed by cache 1073 */ 1074 1075#define isodigit(c) (isdigit(c) && c <= '7') 1076int qword_get(char **bpp, char *dest, int bufsize) 1077{ 1078 /* return bytes copied, or -1 on error */ 1079 char *bp = *bpp; 1080 int len = 0; 1081 1082 while (*bp == ' ') bp++; 1083 1084 if (bp[0] == '\\' && bp[1] == 'x') { 1085 /* HEX STRING */ 1086 bp += 2; 1087 while (isxdigit(bp[0]) && isxdigit(bp[1]) && len < bufsize) { 1088 int byte = isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10; 1089 bp++; 1090 byte <<= 4; 1091 byte |= isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10; 1092 *dest++ = byte; 1093 bp++; 1094 len++; 1095 } 1096 } else { 1097 /* text with \nnn octal quoting */ 1098 while (*bp != ' ' && *bp != '\n' && *bp && len < bufsize-1) { 1099 if (*bp == '\\' && 1100 isodigit(bp[1]) && (bp[1] <= '3') && 1101 isodigit(bp[2]) && 1102 isodigit(bp[3])) { 1103 int byte = (*++bp -'0'); 1104 bp++; 1105 byte = (byte << 3) | (*bp++ - '0'); 1106 byte = (byte << 3) | (*bp++ - '0'); 1107 *dest++ = byte; 1108 len++; 1109 } else { 1110 *dest++ = *bp++; 1111 len++; 1112 } 1113 } 1114 } 1115 1116 if (*bp != ' ' && *bp != '\n' && *bp != '\0') 1117 return -1; 1118 while (*bp == ' ') bp++; 1119 *bpp = bp; 1120 *dest = '\0'; 1121 return len; 1122} 1123EXPORT_SYMBOL_GPL(qword_get); 1124 1125 1126/* 1127 * support /proc/sunrpc/cache/$CACHENAME/content 1128 * as a seqfile. 1129 * We call ->cache_show passing NULL for the item to 1130 * get a header, then pass each real item in the cache 1131 */ 1132 1133struct handle { 1134 struct cache_detail *cd; 1135}; 1136 1137static void *c_start(struct seq_file *m, loff_t *pos) 1138 __acquires(cd->hash_lock) 1139{ 1140 loff_t n = *pos; 1141 unsigned hash, entry; 1142 struct cache_head *ch; 1143 struct cache_detail *cd = ((struct handle*)m->private)->cd; 1144 1145 1146 read_lock(&cd->hash_lock); 1147 if (!n--) 1148 return SEQ_START_TOKEN; 1149 hash = n >> 32; 1150 entry = n & ((1LL<<32) - 1); 1151 1152 for (ch=cd->hash_table[hash]; ch; ch=ch->next) 1153 if (!entry--) 1154 return ch; 1155 n &= ~((1LL<<32) - 1); 1156 do { 1157 hash++; 1158 n += 1LL<<32; 1159 } while(hash < cd->hash_size && 1160 cd->hash_table[hash]==NULL); 1161 if (hash >= cd->hash_size) 1162 return NULL; 1163 *pos = n+1; 1164 return cd->hash_table[hash]; 1165} 1166 1167static void *c_next(struct seq_file *m, void *p, loff_t *pos) 1168{ 1169 struct cache_head *ch = p; 1170 int hash = (*pos >> 32); 1171 struct cache_detail *cd = ((struct handle*)m->private)->cd; 1172 1173 if (p == SEQ_START_TOKEN) 1174 hash = 0; 1175 else if (ch->next == NULL) { 1176 hash++; 1177 *pos += 1LL<<32; 1178 } else { 1179 ++*pos; 1180 return ch->next; 1181 } 1182 *pos &= ~((1LL<<32) - 1); 1183 while (hash < cd->hash_size && 1184 cd->hash_table[hash] == NULL) { 1185 hash++; 1186 *pos += 1LL<<32; 1187 } 1188 if (hash >= cd->hash_size) 1189 return NULL; 1190 ++*pos; 1191 return cd->hash_table[hash]; 1192} 1193 1194static void c_stop(struct seq_file *m, void *p) 1195 __releases(cd->hash_lock) 1196{ 1197 struct cache_detail *cd = ((struct handle*)m->private)->cd; 1198 read_unlock(&cd->hash_lock); 1199} 1200 1201static int c_show(struct seq_file *m, void *p) 1202{ 1203 struct cache_head *cp = p; 1204 struct cache_detail *cd = ((struct handle*)m->private)->cd; 1205 1206 if (p == SEQ_START_TOKEN) 1207 return cd->cache_show(m, cd, NULL); 1208 1209 ifdebug(CACHE) 1210 seq_printf(m, "# expiry=%ld refcnt=%d flags=%lx\n", 1211 cp->expiry_time, atomic_read(&cp->ref.refcount), cp->flags); 1212 cache_get(cp); 1213 if (cache_check(cd, cp, NULL)) 1214 /* cache_check does a cache_put on failure */ 1215 seq_printf(m, "# "); 1216 else 1217 cache_put(cp, cd); 1218 1219 return cd->cache_show(m, cd, cp); 1220} 1221 1222static const struct seq_operations cache_content_op = { 1223 .start = c_start, 1224 .next = c_next, 1225 .stop = c_stop, 1226 .show = c_show, 1227}; 1228 1229static int content_open(struct inode *inode, struct file *file, 1230 struct cache_detail *cd) 1231{ 1232 struct handle *han; 1233 1234 if (!cd || !try_module_get(cd->owner)) 1235 return -EACCES; 1236 han = __seq_open_private(file, &cache_content_op, sizeof(*han)); 1237 if (han == NULL) 1238 return -ENOMEM; 1239 1240 han->cd = cd; 1241 return 0; 1242} 1243 1244static int content_release(struct inode *inode, struct file *file, 1245 struct cache_detail *cd) 1246{ 1247 int ret = seq_release_private(inode, file); 1248 module_put(cd->owner); 1249 return ret; 1250} 1251 1252static int open_flush(struct inode *inode, struct file *file, 1253 struct cache_detail *cd) 1254{ 1255 if (!cd || !try_module_get(cd->owner)) 1256 return -EACCES; 1257 return nonseekable_open(inode, file); 1258} 1259 1260static int release_flush(struct inode *inode, struct file *file, 1261 struct cache_detail *cd) 1262{ 1263 module_put(cd->owner); 1264 return 0; 1265} 1266 1267static ssize_t read_flush(struct file *file, char __user *buf, 1268 size_t count, loff_t *ppos, 1269 struct cache_detail *cd) 1270{ 1271 char tbuf[20]; 1272 unsigned long p = *ppos; 1273 size_t len; 1274 1275 sprintf(tbuf, "%lu\n", cd->flush_time); 1276 len = strlen(tbuf); 1277 if (p >= len) 1278 return 0; 1279 len -= p; 1280 if (len > count) 1281 len = count; 1282 if (copy_to_user(buf, (void*)(tbuf+p), len)) 1283 return -EFAULT; 1284 *ppos += len; 1285 return len; 1286} 1287 1288static ssize_t write_flush(struct file *file, const char __user *buf, 1289 size_t count, loff_t *ppos, 1290 struct cache_detail *cd) 1291{ 1292 char tbuf[20]; 1293 char *ep; 1294 long flushtime; 1295 if (*ppos || count > sizeof(tbuf)-1) 1296 return -EINVAL; 1297 if (copy_from_user(tbuf, buf, count)) 1298 return -EFAULT; 1299 tbuf[count] = 0; 1300 flushtime = simple_strtoul(tbuf, &ep, 0); 1301 if (*ep && *ep != '\n') 1302 return -EINVAL; 1303 1304 cd->flush_time = flushtime; 1305 cd->nextcheck = get_seconds(); 1306 cache_flush(); 1307 1308 *ppos += count; 1309 return count; 1310} 1311 1312static ssize_t cache_read_procfs(struct file *filp, char __user *buf, 1313 size_t count, loff_t *ppos) 1314{ 1315 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; 1316 1317 return cache_read(filp, buf, count, ppos, cd); 1318} 1319 1320static ssize_t cache_write_procfs(struct file *filp, const char __user *buf, 1321 size_t count, loff_t *ppos) 1322{ 1323 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; 1324 1325 return cache_write(filp, buf, count, ppos, cd); 1326} 1327 1328static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait) 1329{ 1330 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; 1331 1332 return cache_poll(filp, wait, cd); 1333} 1334 1335static int cache_ioctl_procfs(struct inode *inode, struct file *filp, 1336 unsigned int cmd, unsigned long arg) 1337{ 1338 struct cache_detail *cd = PDE(inode)->data; 1339 1340 return cache_ioctl(inode, filp, cmd, arg, cd); 1341} 1342 1343static int cache_open_procfs(struct inode *inode, struct file *filp) 1344{ 1345 struct cache_detail *cd = PDE(inode)->data; 1346 1347 return cache_open(inode, filp, cd); 1348} 1349 1350static int cache_release_procfs(struct inode *inode, struct file *filp) 1351{ 1352 struct cache_detail *cd = PDE(inode)->data; 1353 1354 return cache_release(inode, filp, cd); 1355} 1356 1357static const struct file_operations cache_file_operations_procfs = { 1358 .owner = THIS_MODULE, 1359 .llseek = no_llseek, 1360 .read = cache_read_procfs, 1361 .write = cache_write_procfs, 1362 .poll = cache_poll_procfs, 1363 .ioctl = cache_ioctl_procfs, /* for FIONREAD */ 1364 .open = cache_open_procfs, 1365 .release = cache_release_procfs, 1366}; 1367 1368static int content_open_procfs(struct inode *inode, struct file *filp) 1369{ 1370 struct cache_detail *cd = PDE(inode)->data; 1371 1372 return content_open(inode, filp, cd); 1373} 1374 1375static int content_release_procfs(struct inode *inode, struct file *filp) 1376{ 1377 struct cache_detail *cd = PDE(inode)->data; 1378 1379 return content_release(inode, filp, cd); 1380} 1381 1382static const struct file_operations content_file_operations_procfs = { 1383 .open = content_open_procfs, 1384 .read = seq_read, 1385 .llseek = seq_lseek, 1386 .release = content_release_procfs, 1387}; 1388 1389static int open_flush_procfs(struct inode *inode, struct file *filp) 1390{ 1391 struct cache_detail *cd = PDE(inode)->data; 1392 1393 return open_flush(inode, filp, cd); 1394} 1395 1396static int release_flush_procfs(struct inode *inode, struct file *filp) 1397{ 1398 struct cache_detail *cd = PDE(inode)->data; 1399 1400 return release_flush(inode, filp, cd); 1401} 1402 1403static ssize_t read_flush_procfs(struct file *filp, char __user *buf, 1404 size_t count, loff_t *ppos) 1405{ 1406 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; 1407 1408 return read_flush(filp, buf, count, ppos, cd); 1409} 1410 1411static ssize_t write_flush_procfs(struct file *filp, 1412 const char __user *buf, 1413 size_t count, loff_t *ppos) 1414{ 1415 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data; 1416 1417 return write_flush(filp, buf, count, ppos, cd); 1418} 1419 1420static const struct file_operations cache_flush_operations_procfs = { 1421 .open = open_flush_procfs, 1422 .read = read_flush_procfs, 1423 .write = write_flush_procfs, 1424 .release = release_flush_procfs, 1425}; 1426 1427static void remove_cache_proc_entries(struct cache_detail *cd) 1428{ 1429 if (cd->u.procfs.proc_ent == NULL) 1430 return; 1431 if (cd->u.procfs.flush_ent) 1432 remove_proc_entry("flush", cd->u.procfs.proc_ent); 1433 if (cd->u.procfs.channel_ent) 1434 remove_proc_entry("channel", cd->u.procfs.proc_ent); 1435 if (cd->u.procfs.content_ent) 1436 remove_proc_entry("content", cd->u.procfs.proc_ent); 1437 cd->u.procfs.proc_ent = NULL; 1438 remove_proc_entry(cd->name, proc_net_rpc); 1439} 1440 1441#ifdef CONFIG_PROC_FS 1442static int create_cache_proc_entries(struct cache_detail *cd) 1443{ 1444 struct proc_dir_entry *p; 1445 1446 cd->u.procfs.proc_ent = proc_mkdir(cd->name, proc_net_rpc); 1447 if (cd->u.procfs.proc_ent == NULL) 1448 goto out_nomem; 1449 cd->u.procfs.channel_ent = NULL; 1450 cd->u.procfs.content_ent = NULL; 1451 1452 p = proc_create_data("flush", S_IFREG|S_IRUSR|S_IWUSR, 1453 cd->u.procfs.proc_ent, 1454 &cache_flush_operations_procfs, cd); 1455 cd->u.procfs.flush_ent = p; 1456 if (p == NULL) 1457 goto out_nomem; 1458 1459 if (cd->cache_upcall || cd->cache_parse) { 1460 p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR, 1461 cd->u.procfs.proc_ent, 1462 &cache_file_operations_procfs, cd); 1463 cd->u.procfs.channel_ent = p; 1464 if (p == NULL) 1465 goto out_nomem; 1466 } 1467 if (cd->cache_show) { 1468 p = proc_create_data("content", S_IFREG|S_IRUSR|S_IWUSR, 1469 cd->u.procfs.proc_ent, 1470 &content_file_operations_procfs, cd); 1471 cd->u.procfs.content_ent = p; 1472 if (p == NULL) 1473 goto out_nomem; 1474 } 1475 return 0; 1476out_nomem: 1477 remove_cache_proc_entries(cd); 1478 return -ENOMEM; 1479} 1480#else /* CONFIG_PROC_FS */ 1481static int create_cache_proc_entries(struct cache_detail *cd) 1482{ 1483 return 0; 1484} 1485#endif 1486 1487int cache_register(struct cache_detail *cd) 1488{ 1489 int ret; 1490 1491 sunrpc_init_cache_detail(cd); 1492 ret = create_cache_proc_entries(cd); 1493 if (ret) 1494 sunrpc_destroy_cache_detail(cd); 1495 return ret; 1496} 1497EXPORT_SYMBOL_GPL(cache_register); 1498 1499void cache_unregister(struct cache_detail *cd) 1500{ 1501 remove_cache_proc_entries(cd); 1502 sunrpc_destroy_cache_detail(cd); 1503} 1504EXPORT_SYMBOL_GPL(cache_unregister); 1505 1506static ssize_t cache_read_pipefs(struct file *filp, char __user *buf, 1507 size_t count, loff_t *ppos) 1508{ 1509 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; 1510 1511 return cache_read(filp, buf, count, ppos, cd); 1512} 1513 1514static ssize_t cache_write_pipefs(struct file *filp, const char __user *buf, 1515 size_t count, loff_t *ppos) 1516{ 1517 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; 1518 1519 return cache_write(filp, buf, count, ppos, cd); 1520} 1521 1522static unsigned int cache_poll_pipefs(struct file *filp, poll_table *wait) 1523{ 1524 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; 1525 1526 return cache_poll(filp, wait, cd); 1527} 1528 1529static int cache_ioctl_pipefs(struct inode *inode, struct file *filp, 1530 unsigned int cmd, unsigned long arg) 1531{ 1532 struct cache_detail *cd = RPC_I(inode)->private; 1533 1534 return cache_ioctl(inode, filp, cmd, arg, cd); 1535} 1536 1537static int cache_open_pipefs(struct inode *inode, struct file *filp) 1538{ 1539 struct cache_detail *cd = RPC_I(inode)->private; 1540 1541 return cache_open(inode, filp, cd); 1542} 1543 1544static int cache_release_pipefs(struct inode *inode, struct file *filp) 1545{ 1546 struct cache_detail *cd = RPC_I(inode)->private; 1547 1548 return cache_release(inode, filp, cd); 1549} 1550 1551const struct file_operations cache_file_operations_pipefs = { 1552 .owner = THIS_MODULE, 1553 .llseek = no_llseek, 1554 .read = cache_read_pipefs, 1555 .write = cache_write_pipefs, 1556 .poll = cache_poll_pipefs, 1557 .ioctl = cache_ioctl_pipefs, /* for FIONREAD */ 1558 .open = cache_open_pipefs, 1559 .release = cache_release_pipefs, 1560}; 1561 1562static int content_open_pipefs(struct inode *inode, struct file *filp) 1563{ 1564 struct cache_detail *cd = RPC_I(inode)->private; 1565 1566 return content_open(inode, filp, cd); 1567} 1568 1569static int content_release_pipefs(struct inode *inode, struct file *filp) 1570{ 1571 struct cache_detail *cd = RPC_I(inode)->private; 1572 1573 return content_release(inode, filp, cd); 1574} 1575 1576const struct file_operations content_file_operations_pipefs = { 1577 .open = content_open_pipefs, 1578 .read = seq_read, 1579 .llseek = seq_lseek, 1580 .release = content_release_pipefs, 1581}; 1582 1583static int open_flush_pipefs(struct inode *inode, struct file *filp) 1584{ 1585 struct cache_detail *cd = RPC_I(inode)->private; 1586 1587 return open_flush(inode, filp, cd); 1588} 1589 1590static int release_flush_pipefs(struct inode *inode, struct file *filp) 1591{ 1592 struct cache_detail *cd = RPC_I(inode)->private; 1593 1594 return release_flush(inode, filp, cd); 1595} 1596 1597static ssize_t read_flush_pipefs(struct file *filp, char __user *buf, 1598 size_t count, loff_t *ppos) 1599{ 1600 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; 1601 1602 return read_flush(filp, buf, count, ppos, cd); 1603} 1604 1605static ssize_t write_flush_pipefs(struct file *filp, 1606 const char __user *buf, 1607 size_t count, loff_t *ppos) 1608{ 1609 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private; 1610 1611 return write_flush(filp, buf, count, ppos, cd); 1612} 1613 1614const struct file_operations cache_flush_operations_pipefs = { 1615 .open = open_flush_pipefs, 1616 .read = read_flush_pipefs, 1617 .write = write_flush_pipefs, 1618 .release = release_flush_pipefs, 1619}; 1620 1621int sunrpc_cache_register_pipefs(struct dentry *parent, 1622 const char *name, mode_t umode, 1623 struct cache_detail *cd) 1624{ 1625 struct qstr q; 1626 struct dentry *dir; 1627 int ret = 0; 1628 1629 sunrpc_init_cache_detail(cd); 1630 q.name = name; 1631 q.len = strlen(name); 1632 q.hash = full_name_hash(q.name, q.len); 1633 dir = rpc_create_cache_dir(parent, &q, umode, cd); 1634 if (!IS_ERR(dir)) 1635 cd->u.pipefs.dir = dir; 1636 else { 1637 sunrpc_destroy_cache_detail(cd); 1638 ret = PTR_ERR(dir); 1639 } 1640 return ret; 1641} 1642EXPORT_SYMBOL_GPL(sunrpc_cache_register_pipefs); 1643 1644void sunrpc_cache_unregister_pipefs(struct cache_detail *cd) 1645{ 1646 rpc_remove_cache_dir(cd->u.pipefs.dir); 1647 cd->u.pipefs.dir = NULL; 1648 sunrpc_destroy_cache_detail(cd); 1649} 1650EXPORT_SYMBOL_GPL(sunrpc_cache_unregister_pipefs); 1651 1652