4 * Generic code for various authentication-related caches
5 * used by sunrpc clients and servers.
7 * Copyright (C) 2002 Neil Brown <neilb@cse.unsw.edu.au>
9 * Released under terms in GPL version 2. See COPYING.
13 #include <linux/types.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>
37 #define RPCDBG_FACILITY RPCDBG_CACHE
39 static int cache_defer_req(struct cache_req *req, struct cache_head *item);
40 static void cache_revisit_request(struct cache_head *item);
42 static void cache_init(struct cache_head *h)
44 time_t now = get_seconds();
48 h->expiry_time = now + CACHE_NEW_EXPIRY;
49 h->last_refresh = now;
52 struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
53 struct cache_head *key, int hash)
55 struct cache_head **head, **hp;
56 struct cache_head *new = NULL;
58 head = &detail->hash_table[hash];
60 read_lock(&detail->hash_lock);
62 for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
63 struct cache_head *tmp = *hp;
64 if (detail->match(tmp, key)) {
66 read_unlock(&detail->hash_lock);
70 read_unlock(&detail->hash_lock);
71 /* Didn't find anything, insert an empty entry */
73 new = detail->alloc();
76 /* must fully initialise 'new', else
77 * we might get lose if we need to
81 detail->init(new, key);
83 write_lock(&detail->hash_lock);
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)) {
90 write_unlock(&detail->hash_lock);
91 cache_put(new, detail);
99 write_unlock(&detail->hash_lock);
103 EXPORT_SYMBOL_GPL(sunrpc_cache_lookup);
106 static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch);
108 static void cache_fresh_locked(struct cache_head *head, time_t expiry)
110 head->expiry_time = expiry;
111 head->last_refresh = get_seconds();
112 set_bit(CACHE_VALID, &head->flags);
115 static void cache_fresh_unlocked(struct cache_head *head,
116 struct cache_detail *detail)
118 if (test_and_clear_bit(CACHE_PENDING, &head->flags)) {
119 cache_revisit_request(head);
120 cache_dequeue(detail, head);
124 struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
125 struct cache_head *new, struct cache_head *old, int hash)
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
131 struct cache_head **head;
132 struct cache_head *tmp;
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);
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);
146 write_unlock(&detail->hash_lock);
148 /* We need to insert a new entry */
149 tmp = detail->alloc();
151 cache_put(old, detail);
155 detail->init(tmp, old);
156 head = &detail->hash_table[hash];
158 write_lock(&detail->hash_lock);
159 if (test_bit(CACHE_NEGATIVE, &new->flags))
160 set_bit(CACHE_NEGATIVE, &tmp->flags);
162 detail->update(tmp, new);
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);
175 EXPORT_SYMBOL_GPL(sunrpc_cache_update);
177 static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
179 if (!cd->cache_upcall)
181 return cd->cache_upcall(cd, h);
184 static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h)
186 if (!test_bit(CACHE_VALID, &h->flags) ||
187 h->expiry_time < get_seconds())
189 else if (detail->flush_time > h->last_refresh)
193 if (test_bit(CACHE_NEGATIVE, &h->flags))
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.
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
214 int cache_check(struct cache_detail *detail,
215 struct cache_head *h, struct cache_req *rqstp)
218 long refresh_age, age;
220 /* First decide return status as best we can */
221 rv = cache_is_valid(detail, h);
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;
230 } else if (rv == -EAGAIN || age > refresh_age/2) {
231 dprintk("RPC: Want update, refage=%ld, age=%ld\n",
233 if (!test_and_set_bit(CACHE_PENDING, &h->flags)) {
234 switch (cache_make_upcall(detail, h)) {
236 clear_bit(CACHE_PENDING, &h->flags);
237 cache_revisit_request(h);
239 set_bit(CACHE_NEGATIVE, &h->flags);
240 cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY);
241 cache_fresh_unlocked(h, detail);
247 clear_bit(CACHE_PENDING, &h->flags);
248 cache_revisit_request(h);
255 if (cache_defer_req(rqstp, h) < 0) {
256 /* Request is not deferred */
257 rv = cache_is_valid(detail, h);
263 cache_put(h, detail);
266 EXPORT_SYMBOL_GPL(cache_check);
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
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.
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
282 * later we might drop old entries with non-NEVER expiry if that table
283 * is getting 'full' for some definition of 'full'
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
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.
295 * A table is then only scanned if the current time is at least
296 * the nextcheck time.
300 static LIST_HEAD(cache_list);
301 static DEFINE_SPINLOCK(cache_list_lock);
302 static struct cache_detail *current_detail;
303 static int current_index;
305 static void do_cache_clean(struct work_struct *work);
306 static DECLARE_DELAYED_WORK(cache_cleaner, do_cache_clean);
308 static void sunrpc_init_cache_detail(struct cache_detail *cd)
310 rwlock_init(&cd->hash_lock);
311 INIT_LIST_HEAD(&cd->queue);
312 spin_lock(&cache_list_lock);
315 atomic_set(&cd->readers, 0);
318 list_add(&cd->others, &cache_list);
319 spin_unlock(&cache_list_lock);
321 /* start the cleaning process */
322 schedule_delayed_work(&cache_cleaner, 0);
325 static void sunrpc_destroy_cache_detail(struct cache_detail *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);
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);
346 printk(KERN_ERR "nfsd: failed to unregister %s cache\n", cd->name);
349 /* clean cache tries to find something to clean
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.
355 static int cache_clean(void)
358 struct list_head *next;
360 spin_lock(&cache_list_lock);
362 /* find a suitable table if we don't already have one */
363 while (current_detail == NULL ||
364 current_index >= current_detail->hash_size) {
366 next = current_detail->others.next;
368 next = cache_list.next;
369 if (next == &cache_list) {
370 current_detail = NULL;
371 spin_unlock(&cache_list_lock);
374 current_detail = list_entry(next, struct cache_detail, others);
375 if (current_detail->nextcheck > get_seconds())
376 current_index = current_detail->hash_size;
379 current_detail->nextcheck = get_seconds()+30*60;
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)
389 /* find a cleanable entry in the bucket and clean it, or set to next bucket */
391 if (current_detail && current_index < current_detail->hash_size) {
392 struct cache_head *ch, **cp;
393 struct cache_detail *d;
395 write_lock(¤t_detail->hash_lock);
397 /* Ok, now to clean this strand */
399 cp = & current_detail->hash_table[current_index];
400 for (ch = *cp ; ch ; cp = & ch->next, ch = *cp) {
401 if (current_detail->nextcheck > ch->expiry_time)
402 current_detail->nextcheck = ch->expiry_time+1;
403 if (ch->expiry_time >= get_seconds() &&
404 ch->last_refresh >= current_detail->flush_time)
409 current_detail->entries--;
414 write_unlock(¤t_detail->hash_lock);
418 spin_unlock(&cache_list_lock);
420 if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
421 cache_dequeue(current_detail, ch);
422 cache_revisit_request(ch);
426 spin_unlock(&cache_list_lock);
432 * We want to regularly clean the cache, so we need to schedule some work ...
434 static void do_cache_clean(struct work_struct *work)
437 if (cache_clean() == -1)
438 delay = round_jiffies_relative(30*HZ);
440 if (list_empty(&cache_list))
444 schedule_delayed_work(&cache_cleaner, delay);
449 * Clean all caches promptly. This just calls cache_clean
450 * repeatedly until we are sure that every cache has had a chance to
453 void cache_flush(void)
455 while (cache_clean() != -1)
457 while (cache_clean() != -1)
460 EXPORT_SYMBOL_GPL(cache_flush);
462 void cache_purge(struct cache_detail *detail)
464 detail->flush_time = LONG_MAX;
465 detail->nextcheck = get_seconds();
467 detail->flush_time = 1;
469 EXPORT_SYMBOL_GPL(cache_purge);
473 * Deferral and Revisiting of Requests.
475 * If a cache lookup finds a pending entry, we
476 * need to defer the request and revisit it later.
477 * All deferred requests are stored in a hash table,
478 * indexed by "struct cache_head *".
479 * As it may be wasteful to store a whole request
480 * structure, we allow the request to provide a
481 * deferred form, which must contain a
482 * 'struct cache_deferred_req'
483 * This cache_deferred_req contains a method to allow
484 * it to be revisited when cache info is available
487 #define DFR_HASHSIZE (PAGE_SIZE/sizeof(struct list_head))
488 #define DFR_HASH(item) ((((long)item)>>4 ^ (((long)item)>>13)) % DFR_HASHSIZE)
490 #define DFR_MAX 300 /* ??? */
492 static DEFINE_SPINLOCK(cache_defer_lock);
493 static LIST_HEAD(cache_defer_list);
494 static struct list_head cache_defer_hash[DFR_HASHSIZE];
495 static int cache_defer_cnt;
497 static int cache_defer_req(struct cache_req *req, struct cache_head *item)
499 struct cache_deferred_req *dreq, *discard;
500 int hash = DFR_HASH(item);
502 if (cache_defer_cnt >= DFR_MAX) {
503 /* too much in the cache, randomly drop this one,
504 * or continue and drop the oldest below
509 dreq = req->defer(req);
515 spin_lock(&cache_defer_lock);
517 list_add(&dreq->recent, &cache_defer_list);
519 if (cache_defer_hash[hash].next == NULL)
520 INIT_LIST_HEAD(&cache_defer_hash[hash]);
521 list_add(&dreq->hash, &cache_defer_hash[hash]);
523 /* it is in, now maybe clean up */
525 if (++cache_defer_cnt > DFR_MAX) {
526 discard = list_entry(cache_defer_list.prev,
527 struct cache_deferred_req, recent);
528 list_del_init(&discard->recent);
529 list_del_init(&discard->hash);
532 spin_unlock(&cache_defer_lock);
535 /* there was one too many */
536 discard->revisit(discard, 1);
538 if (!test_bit(CACHE_PENDING, &item->flags)) {
539 /* must have just been validated... */
540 cache_revisit_request(item);
546 static void cache_revisit_request(struct cache_head *item)
548 struct cache_deferred_req *dreq;
549 struct list_head pending;
551 struct list_head *lp;
552 int hash = DFR_HASH(item);
554 INIT_LIST_HEAD(&pending);
555 spin_lock(&cache_defer_lock);
557 lp = cache_defer_hash[hash].next;
559 while (lp != &cache_defer_hash[hash]) {
560 dreq = list_entry(lp, struct cache_deferred_req, hash);
562 if (dreq->item == item) {
563 list_del_init(&dreq->hash);
564 list_move(&dreq->recent, &pending);
569 spin_unlock(&cache_defer_lock);
571 while (!list_empty(&pending)) {
572 dreq = list_entry(pending.next, struct cache_deferred_req, recent);
573 list_del_init(&dreq->recent);
574 dreq->revisit(dreq, 0);
578 void cache_clean_deferred(void *owner)
580 struct cache_deferred_req *dreq, *tmp;
581 struct list_head pending;
584 INIT_LIST_HEAD(&pending);
585 spin_lock(&cache_defer_lock);
587 list_for_each_entry_safe(dreq, tmp, &cache_defer_list, recent) {
588 if (dreq->owner == owner) {
589 list_del_init(&dreq->hash);
590 list_move(&dreq->recent, &pending);
594 spin_unlock(&cache_defer_lock);
596 while (!list_empty(&pending)) {
597 dreq = list_entry(pending.next, struct cache_deferred_req, recent);
598 list_del_init(&dreq->recent);
599 dreq->revisit(dreq, 1);
604 * communicate with user-space
606 * We have a magic /proc file - /proc/sunrpc/<cachename>/channel.
607 * On read, you get a full request, or block.
608 * On write, an update request is processed.
609 * Poll works if anything to read, and always allows write.
611 * Implemented by linked list of requests. Each open file has
612 * a ->private that also exists in this list. New requests are added
613 * to the end and may wakeup and preceding readers.
614 * New readers are added to the head. If, on read, an item is found with
615 * CACHE_UPCALLING clear, we free it from the list.
619 static DEFINE_SPINLOCK(queue_lock);
620 static DEFINE_MUTEX(queue_io_mutex);
623 struct list_head list;
624 int reader; /* if 0, then request */
626 struct cache_request {
627 struct cache_queue q;
628 struct cache_head *item;
633 struct cache_reader {
634 struct cache_queue q;
635 int offset; /* if non-0, we have a refcnt on next request */
638 static ssize_t cache_read(struct file *filp, char __user *buf, size_t count,
639 loff_t *ppos, struct cache_detail *cd)
641 struct cache_reader *rp = filp->private_data;
642 struct cache_request *rq;
643 struct inode *inode = filp->f_path.dentry->d_inode;
649 mutex_lock(&inode->i_mutex); /* protect against multiple concurrent
650 * readers on this file */
652 spin_lock(&queue_lock);
653 /* need to find next request */
654 while (rp->q.list.next != &cd->queue &&
655 list_entry(rp->q.list.next, struct cache_queue, list)
657 struct list_head *next = rp->q.list.next;
658 list_move(&rp->q.list, next);
660 if (rp->q.list.next == &cd->queue) {
661 spin_unlock(&queue_lock);
662 mutex_unlock(&inode->i_mutex);
666 rq = container_of(rp->q.list.next, struct cache_request, q.list);
667 BUG_ON(rq->q.reader);
670 spin_unlock(&queue_lock);
672 if (rp->offset == 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) {
674 spin_lock(&queue_lock);
675 list_move(&rp->q.list, &rq->q.list);
676 spin_unlock(&queue_lock);
678 if (rp->offset + count > rq->len)
679 count = rq->len - rp->offset;
681 if (copy_to_user(buf, rq->buf + rp->offset, count))
684 if (rp->offset >= rq->len) {
686 spin_lock(&queue_lock);
687 list_move(&rp->q.list, &rq->q.list);
688 spin_unlock(&queue_lock);
693 if (rp->offset == 0) {
694 /* need to release rq */
695 spin_lock(&queue_lock);
697 if (rq->readers == 0 &&
698 !test_bit(CACHE_PENDING, &rq->item->flags)) {
699 list_del(&rq->q.list);
700 spin_unlock(&queue_lock);
701 cache_put(rq->item, cd);
705 spin_unlock(&queue_lock);
709 mutex_unlock(&inode->i_mutex);
710 return err ? err : count;
713 static ssize_t cache_do_downcall(char *kaddr, const char __user *buf,
714 size_t count, struct cache_detail *cd)
718 if (copy_from_user(kaddr, buf, count))
721 ret = cd->cache_parse(cd, kaddr, count);
727 static ssize_t cache_slow_downcall(const char __user *buf,
728 size_t count, struct cache_detail *cd)
730 static char write_buf[8192]; /* protected by queue_io_mutex */
731 ssize_t ret = -EINVAL;
733 if (count >= sizeof(write_buf))
735 mutex_lock(&queue_io_mutex);
736 ret = cache_do_downcall(write_buf, buf, count, cd);
737 mutex_unlock(&queue_io_mutex);
742 static ssize_t cache_downcall(struct address_space *mapping,
743 const char __user *buf,
744 size_t count, struct cache_detail *cd)
748 ssize_t ret = -ENOMEM;
750 if (count >= PAGE_CACHE_SIZE)
753 page = find_or_create_page(mapping, 0, GFP_KERNEL);
758 ret = cache_do_downcall(kaddr, buf, count, cd);
761 page_cache_release(page);
764 return cache_slow_downcall(buf, count, cd);
767 static ssize_t cache_write(struct file *filp, const char __user *buf,
768 size_t count, loff_t *ppos,
769 struct cache_detail *cd)
771 struct address_space *mapping = filp->f_mapping;
772 struct inode *inode = filp->f_path.dentry->d_inode;
773 ssize_t ret = -EINVAL;
775 if (!cd->cache_parse)
778 mutex_lock(&inode->i_mutex);
779 ret = cache_downcall(mapping, buf, count, cd);
780 mutex_unlock(&inode->i_mutex);
785 static DECLARE_WAIT_QUEUE_HEAD(queue_wait);
787 static unsigned int cache_poll(struct file *filp, poll_table *wait,
788 struct cache_detail *cd)
791 struct cache_reader *rp = filp->private_data;
792 struct cache_queue *cq;
794 poll_wait(filp, &queue_wait, wait);
796 /* alway allow write */
797 mask = POLL_OUT | POLLWRNORM;
802 spin_lock(&queue_lock);
804 for (cq= &rp->q; &cq->list != &cd->queue;
805 cq = list_entry(cq->list.next, struct cache_queue, list))
807 mask |= POLLIN | POLLRDNORM;
810 spin_unlock(&queue_lock);
814 static int cache_ioctl(struct inode *ino, struct file *filp,
815 unsigned int cmd, unsigned long arg,
816 struct cache_detail *cd)
819 struct cache_reader *rp = filp->private_data;
820 struct cache_queue *cq;
822 if (cmd != FIONREAD || !rp)
825 spin_lock(&queue_lock);
827 /* only find the length remaining in current request,
828 * or the length of the next request
830 for (cq= &rp->q; &cq->list != &cd->queue;
831 cq = list_entry(cq->list.next, struct cache_queue, list))
833 struct cache_request *cr =
834 container_of(cq, struct cache_request, q);
835 len = cr->len - rp->offset;
838 spin_unlock(&queue_lock);
840 return put_user(len, (int __user *)arg);
843 static int cache_open(struct inode *inode, struct file *filp,
844 struct cache_detail *cd)
846 struct cache_reader *rp = NULL;
848 if (!cd || !try_module_get(cd->owner))
850 nonseekable_open(inode, filp);
851 if (filp->f_mode & FMODE_READ) {
852 rp = kmalloc(sizeof(*rp), GFP_KERNEL);
857 atomic_inc(&cd->readers);
858 spin_lock(&queue_lock);
859 list_add(&rp->q.list, &cd->queue);
860 spin_unlock(&queue_lock);
862 filp->private_data = rp;
866 static int cache_release(struct inode *inode, struct file *filp,
867 struct cache_detail *cd)
869 struct cache_reader *rp = filp->private_data;
872 spin_lock(&queue_lock);
874 struct cache_queue *cq;
875 for (cq= &rp->q; &cq->list != &cd->queue;
876 cq = list_entry(cq->list.next, struct cache_queue, list))
878 container_of(cq, struct cache_request, q)
884 list_del(&rp->q.list);
885 spin_unlock(&queue_lock);
887 filp->private_data = NULL;
890 cd->last_close = get_seconds();
891 atomic_dec(&cd->readers);
893 module_put(cd->owner);
899 static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch)
901 struct cache_queue *cq;
902 spin_lock(&queue_lock);
903 list_for_each_entry(cq, &detail->queue, list)
905 struct cache_request *cr = container_of(cq, struct cache_request, q);
908 if (cr->readers != 0)
910 list_del(&cr->q.list);
911 spin_unlock(&queue_lock);
912 cache_put(cr->item, detail);
917 spin_unlock(&queue_lock);
921 * Support routines for text-based upcalls.
922 * Fields are separated by spaces.
923 * Fields are either mangled to quote space tab newline slosh with slosh
924 * or a hexified with a leading \x
925 * Record is terminated with newline.
929 void qword_add(char **bpp, int *lp, char *str)
937 while ((c=*str++) && len)
945 *bp++ = '0' + ((c & 0300)>>6);
946 *bp++ = '0' + ((c & 0070)>>3);
947 *bp++ = '0' + ((c & 0007)>>0);
955 if (c || len <1) len = -1;
963 EXPORT_SYMBOL_GPL(qword_add);
965 void qword_addhex(char **bpp, int *lp, char *buf, int blen)
976 while (blen && len >= 2) {
977 unsigned char c = *buf++;
978 *bp++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
979 *bp++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
984 if (blen || len<1) len = -1;
992 EXPORT_SYMBOL_GPL(qword_addhex);
994 static void warn_no_listener(struct cache_detail *detail)
996 if (detail->last_warn != detail->last_close) {
997 detail->last_warn = detail->last_close;
998 if (detail->warn_no_listener)
999 detail->warn_no_listener(detail, detail->last_close != 0);
1004 * register an upcall request to user-space and queue it up for read() by the
1007 * Each request is at most one page long.
1009 int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h,
1010 void (*cache_request)(struct cache_detail *,
1011 struct cache_head *,
1017 struct cache_request *crq;
1021 if (atomic_read(&detail->readers) == 0 &&
1022 detail->last_close < get_seconds() - 30) {
1023 warn_no_listener(detail);
1027 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1031 crq = kmalloc(sizeof (*crq), GFP_KERNEL);
1037 bp = buf; len = PAGE_SIZE;
1039 cache_request(detail, h, &bp, &len);
1047 crq->item = cache_get(h);
1049 crq->len = PAGE_SIZE - len;
1051 spin_lock(&queue_lock);
1052 list_add_tail(&crq->q.list, &detail->queue);
1053 spin_unlock(&queue_lock);
1054 wake_up(&queue_wait);
1057 EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall);
1060 * parse a message from user-space and pass it
1061 * to an appropriate cache
1062 * Messages are, like requests, separated into fields by
1063 * spaces and dequotes as \xHEXSTRING or embedded \nnn octal
1066 * reply cachename expiry key ... content....
1068 * key and content are both parsed by cache
1071 #define isodigit(c) (isdigit(c) && c <= '7')
1072 int qword_get(char **bpp, char *dest, int bufsize)
1074 /* return bytes copied, or -1 on error */
1078 while (*bp == ' ') bp++;
1080 if (bp[0] == '\\' && bp[1] == 'x') {
1083 while (isxdigit(bp[0]) && isxdigit(bp[1]) && len < bufsize) {
1084 int byte = isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10;
1087 byte |= isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10;
1093 /* text with \nnn octal quoting */
1094 while (*bp != ' ' && *bp != '\n' && *bp && len < bufsize-1) {
1096 isodigit(bp[1]) && (bp[1] <= '3') &&
1099 int byte = (*++bp -'0');
1101 byte = (byte << 3) | (*bp++ - '0');
1102 byte = (byte << 3) | (*bp++ - '0');
1112 if (*bp != ' ' && *bp != '\n' && *bp != '\0')
1114 while (*bp == ' ') bp++;
1119 EXPORT_SYMBOL_GPL(qword_get);
1123 * support /proc/sunrpc/cache/$CACHENAME/content
1125 * We call ->cache_show passing NULL for the item to
1126 * get a header, then pass each real item in the cache
1130 struct cache_detail *cd;
1133 static void *c_start(struct seq_file *m, loff_t *pos)
1134 __acquires(cd->hash_lock)
1137 unsigned hash, entry;
1138 struct cache_head *ch;
1139 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1142 read_lock(&cd->hash_lock);
1144 return SEQ_START_TOKEN;
1146 entry = n & ((1LL<<32) - 1);
1148 for (ch=cd->hash_table[hash]; ch; ch=ch->next)
1151 n &= ~((1LL<<32) - 1);
1155 } while(hash < cd->hash_size &&
1156 cd->hash_table[hash]==NULL);
1157 if (hash >= cd->hash_size)
1160 return cd->hash_table[hash];
1163 static void *c_next(struct seq_file *m, void *p, loff_t *pos)
1165 struct cache_head *ch = p;
1166 int hash = (*pos >> 32);
1167 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1169 if (p == SEQ_START_TOKEN)
1171 else if (ch->next == NULL) {
1178 *pos &= ~((1LL<<32) - 1);
1179 while (hash < cd->hash_size &&
1180 cd->hash_table[hash] == NULL) {
1184 if (hash >= cd->hash_size)
1187 return cd->hash_table[hash];
1190 static void c_stop(struct seq_file *m, void *p)
1191 __releases(cd->hash_lock)
1193 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1194 read_unlock(&cd->hash_lock);
1197 static int c_show(struct seq_file *m, void *p)
1199 struct cache_head *cp = p;
1200 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1202 if (p == SEQ_START_TOKEN)
1203 return cd->cache_show(m, cd, NULL);
1206 seq_printf(m, "# expiry=%ld refcnt=%d flags=%lx\n",
1207 cp->expiry_time, atomic_read(&cp->ref.refcount), cp->flags);
1209 if (cache_check(cd, cp, NULL))
1210 /* cache_check does a cache_put on failure */
1211 seq_printf(m, "# ");
1215 return cd->cache_show(m, cd, cp);
1218 static const struct seq_operations cache_content_op = {
1225 static int content_open(struct inode *inode, struct file *file,
1226 struct cache_detail *cd)
1230 if (!cd || !try_module_get(cd->owner))
1232 han = __seq_open_private(file, &cache_content_op, sizeof(*han));
1240 static int content_release(struct inode *inode, struct file *file,
1241 struct cache_detail *cd)
1243 int ret = seq_release_private(inode, file);
1244 module_put(cd->owner);
1248 static int open_flush(struct inode *inode, struct file *file,
1249 struct cache_detail *cd)
1251 if (!cd || !try_module_get(cd->owner))
1253 return nonseekable_open(inode, file);
1256 static int release_flush(struct inode *inode, struct file *file,
1257 struct cache_detail *cd)
1259 module_put(cd->owner);
1263 static ssize_t read_flush(struct file *file, char __user *buf,
1264 size_t count, loff_t *ppos,
1265 struct cache_detail *cd)
1268 unsigned long p = *ppos;
1271 sprintf(tbuf, "%lu\n", cd->flush_time);
1278 if (copy_to_user(buf, (void*)(tbuf+p), len))
1284 static ssize_t write_flush(struct file *file, const char __user *buf,
1285 size_t count, loff_t *ppos,
1286 struct cache_detail *cd)
1291 if (*ppos || count > sizeof(tbuf)-1)
1293 if (copy_from_user(tbuf, buf, count))
1296 flushtime = simple_strtoul(tbuf, &ep, 0);
1297 if (*ep && *ep != '\n')
1300 cd->flush_time = flushtime;
1301 cd->nextcheck = get_seconds();
1308 static ssize_t cache_read_procfs(struct file *filp, char __user *buf,
1309 size_t count, loff_t *ppos)
1311 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1313 return cache_read(filp, buf, count, ppos, cd);
1316 static ssize_t cache_write_procfs(struct file *filp, const char __user *buf,
1317 size_t count, loff_t *ppos)
1319 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1321 return cache_write(filp, buf, count, ppos, cd);
1324 static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait)
1326 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1328 return cache_poll(filp, wait, cd);
1331 static int cache_ioctl_procfs(struct inode *inode, struct file *filp,
1332 unsigned int cmd, unsigned long arg)
1334 struct cache_detail *cd = PDE(inode)->data;
1336 return cache_ioctl(inode, filp, cmd, arg, cd);
1339 static int cache_open_procfs(struct inode *inode, struct file *filp)
1341 struct cache_detail *cd = PDE(inode)->data;
1343 return cache_open(inode, filp, cd);
1346 static int cache_release_procfs(struct inode *inode, struct file *filp)
1348 struct cache_detail *cd = PDE(inode)->data;
1350 return cache_release(inode, filp, cd);
1353 static const struct file_operations cache_file_operations_procfs = {
1354 .owner = THIS_MODULE,
1355 .llseek = no_llseek,
1356 .read = cache_read_procfs,
1357 .write = cache_write_procfs,
1358 .poll = cache_poll_procfs,
1359 .ioctl = cache_ioctl_procfs, /* for FIONREAD */
1360 .open = cache_open_procfs,
1361 .release = cache_release_procfs,
1364 static int content_open_procfs(struct inode *inode, struct file *filp)
1366 struct cache_detail *cd = PDE(inode)->data;
1368 return content_open(inode, filp, cd);
1371 static int content_release_procfs(struct inode *inode, struct file *filp)
1373 struct cache_detail *cd = PDE(inode)->data;
1375 return content_release(inode, filp, cd);
1378 static const struct file_operations content_file_operations_procfs = {
1379 .open = content_open_procfs,
1381 .llseek = seq_lseek,
1382 .release = content_release_procfs,
1385 static int open_flush_procfs(struct inode *inode, struct file *filp)
1387 struct cache_detail *cd = PDE(inode)->data;
1389 return open_flush(inode, filp, cd);
1392 static int release_flush_procfs(struct inode *inode, struct file *filp)
1394 struct cache_detail *cd = PDE(inode)->data;
1396 return release_flush(inode, filp, cd);
1399 static ssize_t read_flush_procfs(struct file *filp, char __user *buf,
1400 size_t count, loff_t *ppos)
1402 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1404 return read_flush(filp, buf, count, ppos, cd);
1407 static ssize_t write_flush_procfs(struct file *filp,
1408 const char __user *buf,
1409 size_t count, loff_t *ppos)
1411 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1413 return write_flush(filp, buf, count, ppos, cd);
1416 static const struct file_operations cache_flush_operations_procfs = {
1417 .open = open_flush_procfs,
1418 .read = read_flush_procfs,
1419 .write = write_flush_procfs,
1420 .release = release_flush_procfs,
1423 static void remove_cache_proc_entries(struct cache_detail *cd)
1425 if (cd->u.procfs.proc_ent == NULL)
1427 if (cd->u.procfs.flush_ent)
1428 remove_proc_entry("flush", cd->u.procfs.proc_ent);
1429 if (cd->u.procfs.channel_ent)
1430 remove_proc_entry("channel", cd->u.procfs.proc_ent);
1431 if (cd->u.procfs.content_ent)
1432 remove_proc_entry("content", cd->u.procfs.proc_ent);
1433 cd->u.procfs.proc_ent = NULL;
1434 remove_proc_entry(cd->name, proc_net_rpc);
1437 #ifdef CONFIG_PROC_FS
1438 static int create_cache_proc_entries(struct cache_detail *cd)
1440 struct proc_dir_entry *p;
1442 cd->u.procfs.proc_ent = proc_mkdir(cd->name, proc_net_rpc);
1443 if (cd->u.procfs.proc_ent == NULL)
1445 cd->u.procfs.channel_ent = NULL;
1446 cd->u.procfs.content_ent = NULL;
1448 p = proc_create_data("flush", S_IFREG|S_IRUSR|S_IWUSR,
1449 cd->u.procfs.proc_ent,
1450 &cache_flush_operations_procfs, cd);
1451 cd->u.procfs.flush_ent = p;
1455 if (cd->cache_upcall || cd->cache_parse) {
1456 p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR,
1457 cd->u.procfs.proc_ent,
1458 &cache_file_operations_procfs, cd);
1459 cd->u.procfs.channel_ent = p;
1463 if (cd->cache_show) {
1464 p = proc_create_data("content", S_IFREG|S_IRUSR|S_IWUSR,
1465 cd->u.procfs.proc_ent,
1466 &content_file_operations_procfs, cd);
1467 cd->u.procfs.content_ent = p;
1473 remove_cache_proc_entries(cd);
1476 #else /* CONFIG_PROC_FS */
1477 static int create_cache_proc_entries(struct cache_detail *cd)
1483 int cache_register(struct cache_detail *cd)
1487 sunrpc_init_cache_detail(cd);
1488 ret = create_cache_proc_entries(cd);
1490 sunrpc_destroy_cache_detail(cd);
1493 EXPORT_SYMBOL_GPL(cache_register);
1495 void cache_unregister(struct cache_detail *cd)
1497 remove_cache_proc_entries(cd);
1498 sunrpc_destroy_cache_detail(cd);
1500 EXPORT_SYMBOL_GPL(cache_unregister);
1502 static ssize_t cache_read_pipefs(struct file *filp, char __user *buf,
1503 size_t count, loff_t *ppos)
1505 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1507 return cache_read(filp, buf, count, ppos, cd);
1510 static ssize_t cache_write_pipefs(struct file *filp, const char __user *buf,
1511 size_t count, loff_t *ppos)
1513 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1515 return cache_write(filp, buf, count, ppos, cd);
1518 static unsigned int cache_poll_pipefs(struct file *filp, poll_table *wait)
1520 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1522 return cache_poll(filp, wait, cd);
1525 static int cache_ioctl_pipefs(struct inode *inode, struct file *filp,
1526 unsigned int cmd, unsigned long arg)
1528 struct cache_detail *cd = RPC_I(inode)->private;
1530 return cache_ioctl(inode, filp, cmd, arg, cd);
1533 static int cache_open_pipefs(struct inode *inode, struct file *filp)
1535 struct cache_detail *cd = RPC_I(inode)->private;
1537 return cache_open(inode, filp, cd);
1540 static int cache_release_pipefs(struct inode *inode, struct file *filp)
1542 struct cache_detail *cd = RPC_I(inode)->private;
1544 return cache_release(inode, filp, cd);
1547 const struct file_operations cache_file_operations_pipefs = {
1548 .owner = THIS_MODULE,
1549 .llseek = no_llseek,
1550 .read = cache_read_pipefs,
1551 .write = cache_write_pipefs,
1552 .poll = cache_poll_pipefs,
1553 .ioctl = cache_ioctl_pipefs, /* for FIONREAD */
1554 .open = cache_open_pipefs,
1555 .release = cache_release_pipefs,
1558 static int content_open_pipefs(struct inode *inode, struct file *filp)
1560 struct cache_detail *cd = RPC_I(inode)->private;
1562 return content_open(inode, filp, cd);
1565 static int content_release_pipefs(struct inode *inode, struct file *filp)
1567 struct cache_detail *cd = RPC_I(inode)->private;
1569 return content_release(inode, filp, cd);
1572 const struct file_operations content_file_operations_pipefs = {
1573 .open = content_open_pipefs,
1575 .llseek = seq_lseek,
1576 .release = content_release_pipefs,
1579 static int open_flush_pipefs(struct inode *inode, struct file *filp)
1581 struct cache_detail *cd = RPC_I(inode)->private;
1583 return open_flush(inode, filp, cd);
1586 static int release_flush_pipefs(struct inode *inode, struct file *filp)
1588 struct cache_detail *cd = RPC_I(inode)->private;
1590 return release_flush(inode, filp, cd);
1593 static ssize_t read_flush_pipefs(struct file *filp, char __user *buf,
1594 size_t count, loff_t *ppos)
1596 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1598 return read_flush(filp, buf, count, ppos, cd);
1601 static ssize_t write_flush_pipefs(struct file *filp,
1602 const char __user *buf,
1603 size_t count, loff_t *ppos)
1605 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1607 return write_flush(filp, buf, count, ppos, cd);
1610 const struct file_operations cache_flush_operations_pipefs = {
1611 .open = open_flush_pipefs,
1612 .read = read_flush_pipefs,
1613 .write = write_flush_pipefs,
1614 .release = release_flush_pipefs,
1617 int sunrpc_cache_register_pipefs(struct dentry *parent,
1618 const char *name, mode_t umode,
1619 struct cache_detail *cd)
1625 sunrpc_init_cache_detail(cd);
1627 q.len = strlen(name);
1628 q.hash = full_name_hash(q.name, q.len);
1629 dir = rpc_create_cache_dir(parent, &q, umode, cd);
1631 cd->u.pipefs.dir = dir;
1633 sunrpc_destroy_cache_detail(cd);
1638 EXPORT_SYMBOL_GPL(sunrpc_cache_register_pipefs);
1640 void sunrpc_cache_unregister_pipefs(struct cache_detail *cd)
1642 rpc_remove_cache_dir(cd->u.pipefs.dir);
1643 cd->u.pipefs.dir = NULL;
1644 sunrpc_destroy_cache_detail(cd);
1646 EXPORT_SYMBOL_GPL(sunrpc_cache_unregister_pipefs);