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];
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)
407 if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
408 cache_dequeue(current_detail, ch);
410 if (atomic_read(&ch->ref.refcount) == 1)
416 current_detail->entries--;
419 write_unlock(¤t_detail->hash_lock);
423 spin_unlock(&cache_list_lock);
425 cache_revisit_request(ch);
429 spin_unlock(&cache_list_lock);
435 * We want to regularly clean the cache, so we need to schedule some work ...
437 static void do_cache_clean(struct work_struct *work)
440 if (cache_clean() == -1)
441 delay = round_jiffies_relative(30*HZ);
443 if (list_empty(&cache_list))
447 schedule_delayed_work(&cache_cleaner, delay);
452 * Clean all caches promptly. This just calls cache_clean
453 * repeatedly until we are sure that every cache has had a chance to
456 void cache_flush(void)
458 while (cache_clean() != -1)
460 while (cache_clean() != -1)
463 EXPORT_SYMBOL_GPL(cache_flush);
465 void cache_purge(struct cache_detail *detail)
467 detail->flush_time = LONG_MAX;
468 detail->nextcheck = get_seconds();
470 detail->flush_time = 1;
472 EXPORT_SYMBOL_GPL(cache_purge);
476 * Deferral and Revisiting of Requests.
478 * If a cache lookup finds a pending entry, we
479 * need to defer the request and revisit it later.
480 * All deferred requests are stored in a hash table,
481 * indexed by "struct cache_head *".
482 * As it may be wasteful to store a whole request
483 * structure, we allow the request to provide a
484 * deferred form, which must contain a
485 * 'struct cache_deferred_req'
486 * This cache_deferred_req contains a method to allow
487 * it to be revisited when cache info is available
490 #define DFR_HASHSIZE (PAGE_SIZE/sizeof(struct list_head))
491 #define DFR_HASH(item) ((((long)item)>>4 ^ (((long)item)>>13)) % DFR_HASHSIZE)
493 #define DFR_MAX 300 /* ??? */
495 static DEFINE_SPINLOCK(cache_defer_lock);
496 static LIST_HEAD(cache_defer_list);
497 static struct list_head cache_defer_hash[DFR_HASHSIZE];
498 static int cache_defer_cnt;
500 static int cache_defer_req(struct cache_req *req, struct cache_head *item)
502 struct cache_deferred_req *dreq, *discard;
503 int hash = DFR_HASH(item);
505 if (cache_defer_cnt >= DFR_MAX) {
506 /* too much in the cache, randomly drop this one,
507 * or continue and drop the oldest below
512 dreq = req->defer(req);
518 spin_lock(&cache_defer_lock);
520 list_add(&dreq->recent, &cache_defer_list);
522 if (cache_defer_hash[hash].next == NULL)
523 INIT_LIST_HEAD(&cache_defer_hash[hash]);
524 list_add(&dreq->hash, &cache_defer_hash[hash]);
526 /* it is in, now maybe clean up */
528 if (++cache_defer_cnt > DFR_MAX) {
529 discard = list_entry(cache_defer_list.prev,
530 struct cache_deferred_req, recent);
531 list_del_init(&discard->recent);
532 list_del_init(&discard->hash);
535 spin_unlock(&cache_defer_lock);
538 /* there was one too many */
539 discard->revisit(discard, 1);
541 if (!test_bit(CACHE_PENDING, &item->flags)) {
542 /* must have just been validated... */
543 cache_revisit_request(item);
549 static void cache_revisit_request(struct cache_head *item)
551 struct cache_deferred_req *dreq;
552 struct list_head pending;
554 struct list_head *lp;
555 int hash = DFR_HASH(item);
557 INIT_LIST_HEAD(&pending);
558 spin_lock(&cache_defer_lock);
560 lp = cache_defer_hash[hash].next;
562 while (lp != &cache_defer_hash[hash]) {
563 dreq = list_entry(lp, struct cache_deferred_req, hash);
565 if (dreq->item == item) {
566 list_del_init(&dreq->hash);
567 list_move(&dreq->recent, &pending);
572 spin_unlock(&cache_defer_lock);
574 while (!list_empty(&pending)) {
575 dreq = list_entry(pending.next, struct cache_deferred_req, recent);
576 list_del_init(&dreq->recent);
577 dreq->revisit(dreq, 0);
581 void cache_clean_deferred(void *owner)
583 struct cache_deferred_req *dreq, *tmp;
584 struct list_head pending;
587 INIT_LIST_HEAD(&pending);
588 spin_lock(&cache_defer_lock);
590 list_for_each_entry_safe(dreq, tmp, &cache_defer_list, recent) {
591 if (dreq->owner == owner) {
592 list_del_init(&dreq->hash);
593 list_move(&dreq->recent, &pending);
597 spin_unlock(&cache_defer_lock);
599 while (!list_empty(&pending)) {
600 dreq = list_entry(pending.next, struct cache_deferred_req, recent);
601 list_del_init(&dreq->recent);
602 dreq->revisit(dreq, 1);
607 * communicate with user-space
609 * We have a magic /proc file - /proc/sunrpc/<cachename>/channel.
610 * On read, you get a full request, or block.
611 * On write, an update request is processed.
612 * Poll works if anything to read, and always allows write.
614 * Implemented by linked list of requests. Each open file has
615 * a ->private that also exists in this list. New requests are added
616 * to the end and may wakeup and preceding readers.
617 * New readers are added to the head. If, on read, an item is found with
618 * CACHE_UPCALLING clear, we free it from the list.
622 static DEFINE_SPINLOCK(queue_lock);
623 static DEFINE_MUTEX(queue_io_mutex);
626 struct list_head list;
627 int reader; /* if 0, then request */
629 struct cache_request {
630 struct cache_queue q;
631 struct cache_head *item;
636 struct cache_reader {
637 struct cache_queue q;
638 int offset; /* if non-0, we have a refcnt on next request */
641 static ssize_t cache_read(struct file *filp, char __user *buf, size_t count,
642 loff_t *ppos, struct cache_detail *cd)
644 struct cache_reader *rp = filp->private_data;
645 struct cache_request *rq;
646 struct inode *inode = filp->f_path.dentry->d_inode;
652 mutex_lock(&inode->i_mutex); /* protect against multiple concurrent
653 * readers on this file */
655 spin_lock(&queue_lock);
656 /* need to find next request */
657 while (rp->q.list.next != &cd->queue &&
658 list_entry(rp->q.list.next, struct cache_queue, list)
660 struct list_head *next = rp->q.list.next;
661 list_move(&rp->q.list, next);
663 if (rp->q.list.next == &cd->queue) {
664 spin_unlock(&queue_lock);
665 mutex_unlock(&inode->i_mutex);
669 rq = container_of(rp->q.list.next, struct cache_request, q.list);
670 BUG_ON(rq->q.reader);
673 spin_unlock(&queue_lock);
675 if (rp->offset == 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) {
677 spin_lock(&queue_lock);
678 list_move(&rp->q.list, &rq->q.list);
679 spin_unlock(&queue_lock);
681 if (rp->offset + count > rq->len)
682 count = rq->len - rp->offset;
684 if (copy_to_user(buf, rq->buf + rp->offset, count))
687 if (rp->offset >= rq->len) {
689 spin_lock(&queue_lock);
690 list_move(&rp->q.list, &rq->q.list);
691 spin_unlock(&queue_lock);
696 if (rp->offset == 0) {
697 /* need to release rq */
698 spin_lock(&queue_lock);
700 if (rq->readers == 0 &&
701 !test_bit(CACHE_PENDING, &rq->item->flags)) {
702 list_del(&rq->q.list);
703 spin_unlock(&queue_lock);
704 cache_put(rq->item, cd);
708 spin_unlock(&queue_lock);
712 mutex_unlock(&inode->i_mutex);
713 return err ? err : count;
716 static ssize_t cache_do_downcall(char *kaddr, const char __user *buf,
717 size_t count, struct cache_detail *cd)
721 if (copy_from_user(kaddr, buf, count))
724 ret = cd->cache_parse(cd, kaddr, count);
730 static ssize_t cache_slow_downcall(const char __user *buf,
731 size_t count, struct cache_detail *cd)
733 static char write_buf[8192]; /* protected by queue_io_mutex */
734 ssize_t ret = -EINVAL;
736 if (count >= sizeof(write_buf))
738 mutex_lock(&queue_io_mutex);
739 ret = cache_do_downcall(write_buf, buf, count, cd);
740 mutex_unlock(&queue_io_mutex);
745 static ssize_t cache_downcall(struct address_space *mapping,
746 const char __user *buf,
747 size_t count, struct cache_detail *cd)
751 ssize_t ret = -ENOMEM;
753 if (count >= PAGE_CACHE_SIZE)
756 page = find_or_create_page(mapping, 0, GFP_KERNEL);
761 ret = cache_do_downcall(kaddr, buf, count, cd);
764 page_cache_release(page);
767 return cache_slow_downcall(buf, count, cd);
770 static ssize_t cache_write(struct file *filp, const char __user *buf,
771 size_t count, loff_t *ppos,
772 struct cache_detail *cd)
774 struct address_space *mapping = filp->f_mapping;
775 struct inode *inode = filp->f_path.dentry->d_inode;
776 ssize_t ret = -EINVAL;
778 if (!cd->cache_parse)
781 mutex_lock(&inode->i_mutex);
782 ret = cache_downcall(mapping, buf, count, cd);
783 mutex_unlock(&inode->i_mutex);
788 static DECLARE_WAIT_QUEUE_HEAD(queue_wait);
790 static unsigned int cache_poll(struct file *filp, poll_table *wait,
791 struct cache_detail *cd)
794 struct cache_reader *rp = filp->private_data;
795 struct cache_queue *cq;
797 poll_wait(filp, &queue_wait, wait);
799 /* alway allow write */
800 mask = POLL_OUT | POLLWRNORM;
805 spin_lock(&queue_lock);
807 for (cq= &rp->q; &cq->list != &cd->queue;
808 cq = list_entry(cq->list.next, struct cache_queue, list))
810 mask |= POLLIN | POLLRDNORM;
813 spin_unlock(&queue_lock);
817 static int cache_ioctl(struct inode *ino, struct file *filp,
818 unsigned int cmd, unsigned long arg,
819 struct cache_detail *cd)
822 struct cache_reader *rp = filp->private_data;
823 struct cache_queue *cq;
825 if (cmd != FIONREAD || !rp)
828 spin_lock(&queue_lock);
830 /* only find the length remaining in current request,
831 * or the length of the next request
833 for (cq= &rp->q; &cq->list != &cd->queue;
834 cq = list_entry(cq->list.next, struct cache_queue, list))
836 struct cache_request *cr =
837 container_of(cq, struct cache_request, q);
838 len = cr->len - rp->offset;
841 spin_unlock(&queue_lock);
843 return put_user(len, (int __user *)arg);
846 static int cache_open(struct inode *inode, struct file *filp,
847 struct cache_detail *cd)
849 struct cache_reader *rp = NULL;
851 if (!cd || !try_module_get(cd->owner))
853 nonseekable_open(inode, filp);
854 if (filp->f_mode & FMODE_READ) {
855 rp = kmalloc(sizeof(*rp), GFP_KERNEL);
860 atomic_inc(&cd->readers);
861 spin_lock(&queue_lock);
862 list_add(&rp->q.list, &cd->queue);
863 spin_unlock(&queue_lock);
865 filp->private_data = rp;
869 static int cache_release(struct inode *inode, struct file *filp,
870 struct cache_detail *cd)
872 struct cache_reader *rp = filp->private_data;
875 spin_lock(&queue_lock);
877 struct cache_queue *cq;
878 for (cq= &rp->q; &cq->list != &cd->queue;
879 cq = list_entry(cq->list.next, struct cache_queue, list))
881 container_of(cq, struct cache_request, q)
887 list_del(&rp->q.list);
888 spin_unlock(&queue_lock);
890 filp->private_data = NULL;
893 cd->last_close = get_seconds();
894 atomic_dec(&cd->readers);
896 module_put(cd->owner);
902 static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch)
904 struct cache_queue *cq;
905 spin_lock(&queue_lock);
906 list_for_each_entry(cq, &detail->queue, list)
908 struct cache_request *cr = container_of(cq, struct cache_request, q);
911 if (cr->readers != 0)
913 list_del(&cr->q.list);
914 spin_unlock(&queue_lock);
915 cache_put(cr->item, detail);
920 spin_unlock(&queue_lock);
924 * Support routines for text-based upcalls.
925 * Fields are separated by spaces.
926 * Fields are either mangled to quote space tab newline slosh with slosh
927 * or a hexified with a leading \x
928 * Record is terminated with newline.
932 void qword_add(char **bpp, int *lp, char *str)
940 while ((c=*str++) && len)
948 *bp++ = '0' + ((c & 0300)>>6);
949 *bp++ = '0' + ((c & 0070)>>3);
950 *bp++ = '0' + ((c & 0007)>>0);
958 if (c || len <1) len = -1;
966 EXPORT_SYMBOL_GPL(qword_add);
968 void qword_addhex(char **bpp, int *lp, char *buf, int blen)
979 while (blen && len >= 2) {
980 unsigned char c = *buf++;
981 *bp++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
982 *bp++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
987 if (blen || len<1) len = -1;
995 EXPORT_SYMBOL_GPL(qword_addhex);
997 static void warn_no_listener(struct cache_detail *detail)
999 if (detail->last_warn != detail->last_close) {
1000 detail->last_warn = detail->last_close;
1001 if (detail->warn_no_listener)
1002 detail->warn_no_listener(detail, detail->last_close != 0);
1007 * register an upcall request to user-space and queue it up for read() by the
1010 * Each request is at most one page long.
1012 int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h,
1013 void (*cache_request)(struct cache_detail *,
1014 struct cache_head *,
1020 struct cache_request *crq;
1024 if (atomic_read(&detail->readers) == 0 &&
1025 detail->last_close < get_seconds() - 30) {
1026 warn_no_listener(detail);
1030 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1034 crq = kmalloc(sizeof (*crq), GFP_KERNEL);
1040 bp = buf; len = PAGE_SIZE;
1042 cache_request(detail, h, &bp, &len);
1050 crq->item = cache_get(h);
1052 crq->len = PAGE_SIZE - len;
1054 spin_lock(&queue_lock);
1055 list_add_tail(&crq->q.list, &detail->queue);
1056 spin_unlock(&queue_lock);
1057 wake_up(&queue_wait);
1060 EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall);
1063 * parse a message from user-space and pass it
1064 * to an appropriate cache
1065 * Messages are, like requests, separated into fields by
1066 * spaces and dequotes as \xHEXSTRING or embedded \nnn octal
1069 * reply cachename expiry key ... content....
1071 * key and content are both parsed by cache
1074 #define isodigit(c) (isdigit(c) && c <= '7')
1075 int qword_get(char **bpp, char *dest, int bufsize)
1077 /* return bytes copied, or -1 on error */
1081 while (*bp == ' ') bp++;
1083 if (bp[0] == '\\' && bp[1] == 'x') {
1086 while (isxdigit(bp[0]) && isxdigit(bp[1]) && len < bufsize) {
1087 int byte = isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10;
1090 byte |= isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10;
1096 /* text with \nnn octal quoting */
1097 while (*bp != ' ' && *bp != '\n' && *bp && len < bufsize-1) {
1099 isodigit(bp[1]) && (bp[1] <= '3') &&
1102 int byte = (*++bp -'0');
1104 byte = (byte << 3) | (*bp++ - '0');
1105 byte = (byte << 3) | (*bp++ - '0');
1115 if (*bp != ' ' && *bp != '\n' && *bp != '\0')
1117 while (*bp == ' ') bp++;
1122 EXPORT_SYMBOL_GPL(qword_get);
1126 * support /proc/sunrpc/cache/$CACHENAME/content
1128 * We call ->cache_show passing NULL for the item to
1129 * get a header, then pass each real item in the cache
1133 struct cache_detail *cd;
1136 static void *c_start(struct seq_file *m, loff_t *pos)
1137 __acquires(cd->hash_lock)
1140 unsigned hash, entry;
1141 struct cache_head *ch;
1142 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1145 read_lock(&cd->hash_lock);
1147 return SEQ_START_TOKEN;
1149 entry = n & ((1LL<<32) - 1);
1151 for (ch=cd->hash_table[hash]; ch; ch=ch->next)
1154 n &= ~((1LL<<32) - 1);
1158 } while(hash < cd->hash_size &&
1159 cd->hash_table[hash]==NULL);
1160 if (hash >= cd->hash_size)
1163 return cd->hash_table[hash];
1166 static void *c_next(struct seq_file *m, void *p, loff_t *pos)
1168 struct cache_head *ch = p;
1169 int hash = (*pos >> 32);
1170 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1172 if (p == SEQ_START_TOKEN)
1174 else if (ch->next == NULL) {
1181 *pos &= ~((1LL<<32) - 1);
1182 while (hash < cd->hash_size &&
1183 cd->hash_table[hash] == NULL) {
1187 if (hash >= cd->hash_size)
1190 return cd->hash_table[hash];
1193 static void c_stop(struct seq_file *m, void *p)
1194 __releases(cd->hash_lock)
1196 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1197 read_unlock(&cd->hash_lock);
1200 static int c_show(struct seq_file *m, void *p)
1202 struct cache_head *cp = p;
1203 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1205 if (p == SEQ_START_TOKEN)
1206 return cd->cache_show(m, cd, NULL);
1209 seq_printf(m, "# expiry=%ld refcnt=%d flags=%lx\n",
1210 cp->expiry_time, atomic_read(&cp->ref.refcount), cp->flags);
1212 if (cache_check(cd, cp, NULL))
1213 /* cache_check does a cache_put on failure */
1214 seq_printf(m, "# ");
1218 return cd->cache_show(m, cd, cp);
1221 static const struct seq_operations cache_content_op = {
1228 static int content_open(struct inode *inode, struct file *file,
1229 struct cache_detail *cd)
1233 if (!cd || !try_module_get(cd->owner))
1235 han = __seq_open_private(file, &cache_content_op, sizeof(*han));
1243 static int content_release(struct inode *inode, struct file *file,
1244 struct cache_detail *cd)
1246 int ret = seq_release_private(inode, file);
1247 module_put(cd->owner);
1251 static int open_flush(struct inode *inode, struct file *file,
1252 struct cache_detail *cd)
1254 if (!cd || !try_module_get(cd->owner))
1256 return nonseekable_open(inode, file);
1259 static int release_flush(struct inode *inode, struct file *file,
1260 struct cache_detail *cd)
1262 module_put(cd->owner);
1266 static ssize_t read_flush(struct file *file, char __user *buf,
1267 size_t count, loff_t *ppos,
1268 struct cache_detail *cd)
1271 unsigned long p = *ppos;
1274 sprintf(tbuf, "%lu\n", cd->flush_time);
1281 if (copy_to_user(buf, (void*)(tbuf+p), len))
1287 static ssize_t write_flush(struct file *file, const char __user *buf,
1288 size_t count, loff_t *ppos,
1289 struct cache_detail *cd)
1294 if (*ppos || count > sizeof(tbuf)-1)
1296 if (copy_from_user(tbuf, buf, count))
1299 flushtime = simple_strtoul(tbuf, &ep, 0);
1300 if (*ep && *ep != '\n')
1303 cd->flush_time = flushtime;
1304 cd->nextcheck = get_seconds();
1311 static ssize_t cache_read_procfs(struct file *filp, char __user *buf,
1312 size_t count, loff_t *ppos)
1314 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1316 return cache_read(filp, buf, count, ppos, cd);
1319 static ssize_t cache_write_procfs(struct file *filp, const char __user *buf,
1320 size_t count, loff_t *ppos)
1322 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1324 return cache_write(filp, buf, count, ppos, cd);
1327 static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait)
1329 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1331 return cache_poll(filp, wait, cd);
1334 static int cache_ioctl_procfs(struct inode *inode, struct file *filp,
1335 unsigned int cmd, unsigned long arg)
1337 struct cache_detail *cd = PDE(inode)->data;
1339 return cache_ioctl(inode, filp, cmd, arg, cd);
1342 static int cache_open_procfs(struct inode *inode, struct file *filp)
1344 struct cache_detail *cd = PDE(inode)->data;
1346 return cache_open(inode, filp, cd);
1349 static int cache_release_procfs(struct inode *inode, struct file *filp)
1351 struct cache_detail *cd = PDE(inode)->data;
1353 return cache_release(inode, filp, cd);
1356 static const struct file_operations cache_file_operations_procfs = {
1357 .owner = THIS_MODULE,
1358 .llseek = no_llseek,
1359 .read = cache_read_procfs,
1360 .write = cache_write_procfs,
1361 .poll = cache_poll_procfs,
1362 .ioctl = cache_ioctl_procfs, /* for FIONREAD */
1363 .open = cache_open_procfs,
1364 .release = cache_release_procfs,
1367 static int content_open_procfs(struct inode *inode, struct file *filp)
1369 struct cache_detail *cd = PDE(inode)->data;
1371 return content_open(inode, filp, cd);
1374 static int content_release_procfs(struct inode *inode, struct file *filp)
1376 struct cache_detail *cd = PDE(inode)->data;
1378 return content_release(inode, filp, cd);
1381 static const struct file_operations content_file_operations_procfs = {
1382 .open = content_open_procfs,
1384 .llseek = seq_lseek,
1385 .release = content_release_procfs,
1388 static int open_flush_procfs(struct inode *inode, struct file *filp)
1390 struct cache_detail *cd = PDE(inode)->data;
1392 return open_flush(inode, filp, cd);
1395 static int release_flush_procfs(struct inode *inode, struct file *filp)
1397 struct cache_detail *cd = PDE(inode)->data;
1399 return release_flush(inode, filp, cd);
1402 static ssize_t read_flush_procfs(struct file *filp, char __user *buf,
1403 size_t count, loff_t *ppos)
1405 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1407 return read_flush(filp, buf, count, ppos, cd);
1410 static ssize_t write_flush_procfs(struct file *filp,
1411 const char __user *buf,
1412 size_t count, loff_t *ppos)
1414 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1416 return write_flush(filp, buf, count, ppos, cd);
1419 static const struct file_operations cache_flush_operations_procfs = {
1420 .open = open_flush_procfs,
1421 .read = read_flush_procfs,
1422 .write = write_flush_procfs,
1423 .release = release_flush_procfs,
1426 static void remove_cache_proc_entries(struct cache_detail *cd)
1428 if (cd->u.procfs.proc_ent == NULL)
1430 if (cd->u.procfs.flush_ent)
1431 remove_proc_entry("flush", cd->u.procfs.proc_ent);
1432 if (cd->u.procfs.channel_ent)
1433 remove_proc_entry("channel", cd->u.procfs.proc_ent);
1434 if (cd->u.procfs.content_ent)
1435 remove_proc_entry("content", cd->u.procfs.proc_ent);
1436 cd->u.procfs.proc_ent = NULL;
1437 remove_proc_entry(cd->name, proc_net_rpc);
1440 #ifdef CONFIG_PROC_FS
1441 static int create_cache_proc_entries(struct cache_detail *cd)
1443 struct proc_dir_entry *p;
1445 cd->u.procfs.proc_ent = proc_mkdir(cd->name, proc_net_rpc);
1446 if (cd->u.procfs.proc_ent == NULL)
1448 cd->u.procfs.channel_ent = NULL;
1449 cd->u.procfs.content_ent = NULL;
1451 p = proc_create_data("flush", S_IFREG|S_IRUSR|S_IWUSR,
1452 cd->u.procfs.proc_ent,
1453 &cache_flush_operations_procfs, cd);
1454 cd->u.procfs.flush_ent = p;
1458 if (cd->cache_upcall || cd->cache_parse) {
1459 p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR,
1460 cd->u.procfs.proc_ent,
1461 &cache_file_operations_procfs, cd);
1462 cd->u.procfs.channel_ent = p;
1466 if (cd->cache_show) {
1467 p = proc_create_data("content", S_IFREG|S_IRUSR|S_IWUSR,
1468 cd->u.procfs.proc_ent,
1469 &content_file_operations_procfs, cd);
1470 cd->u.procfs.content_ent = p;
1476 remove_cache_proc_entries(cd);
1479 #else /* CONFIG_PROC_FS */
1480 static int create_cache_proc_entries(struct cache_detail *cd)
1486 int cache_register(struct cache_detail *cd)
1490 sunrpc_init_cache_detail(cd);
1491 ret = create_cache_proc_entries(cd);
1493 sunrpc_destroy_cache_detail(cd);
1496 EXPORT_SYMBOL_GPL(cache_register);
1498 void cache_unregister(struct cache_detail *cd)
1500 remove_cache_proc_entries(cd);
1501 sunrpc_destroy_cache_detail(cd);
1503 EXPORT_SYMBOL_GPL(cache_unregister);
1505 static ssize_t cache_read_pipefs(struct file *filp, char __user *buf,
1506 size_t count, loff_t *ppos)
1508 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1510 return cache_read(filp, buf, count, ppos, cd);
1513 static ssize_t cache_write_pipefs(struct file *filp, const char __user *buf,
1514 size_t count, loff_t *ppos)
1516 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1518 return cache_write(filp, buf, count, ppos, cd);
1521 static unsigned int cache_poll_pipefs(struct file *filp, poll_table *wait)
1523 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1525 return cache_poll(filp, wait, cd);
1528 static int cache_ioctl_pipefs(struct inode *inode, struct file *filp,
1529 unsigned int cmd, unsigned long arg)
1531 struct cache_detail *cd = RPC_I(inode)->private;
1533 return cache_ioctl(inode, filp, cmd, arg, cd);
1536 static int cache_open_pipefs(struct inode *inode, struct file *filp)
1538 struct cache_detail *cd = RPC_I(inode)->private;
1540 return cache_open(inode, filp, cd);
1543 static int cache_release_pipefs(struct inode *inode, struct file *filp)
1545 struct cache_detail *cd = RPC_I(inode)->private;
1547 return cache_release(inode, filp, cd);
1550 const struct file_operations cache_file_operations_pipefs = {
1551 .owner = THIS_MODULE,
1552 .llseek = no_llseek,
1553 .read = cache_read_pipefs,
1554 .write = cache_write_pipefs,
1555 .poll = cache_poll_pipefs,
1556 .ioctl = cache_ioctl_pipefs, /* for FIONREAD */
1557 .open = cache_open_pipefs,
1558 .release = cache_release_pipefs,
1561 static int content_open_pipefs(struct inode *inode, struct file *filp)
1563 struct cache_detail *cd = RPC_I(inode)->private;
1565 return content_open(inode, filp, cd);
1568 static int content_release_pipefs(struct inode *inode, struct file *filp)
1570 struct cache_detail *cd = RPC_I(inode)->private;
1572 return content_release(inode, filp, cd);
1575 const struct file_operations content_file_operations_pipefs = {
1576 .open = content_open_pipefs,
1578 .llseek = seq_lseek,
1579 .release = content_release_pipefs,
1582 static int open_flush_pipefs(struct inode *inode, struct file *filp)
1584 struct cache_detail *cd = RPC_I(inode)->private;
1586 return open_flush(inode, filp, cd);
1589 static int release_flush_pipefs(struct inode *inode, struct file *filp)
1591 struct cache_detail *cd = RPC_I(inode)->private;
1593 return release_flush(inode, filp, cd);
1596 static ssize_t read_flush_pipefs(struct file *filp, char __user *buf,
1597 size_t count, loff_t *ppos)
1599 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1601 return read_flush(filp, buf, count, ppos, cd);
1604 static ssize_t write_flush_pipefs(struct file *filp,
1605 const char __user *buf,
1606 size_t count, loff_t *ppos)
1608 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1610 return write_flush(filp, buf, count, ppos, cd);
1613 const struct file_operations cache_flush_operations_pipefs = {
1614 .open = open_flush_pipefs,
1615 .read = read_flush_pipefs,
1616 .write = write_flush_pipefs,
1617 .release = release_flush_pipefs,
1620 int sunrpc_cache_register_pipefs(struct dentry *parent,
1621 const char *name, mode_t umode,
1622 struct cache_detail *cd)
1628 sunrpc_init_cache_detail(cd);
1630 q.len = strlen(name);
1631 q.hash = full_name_hash(q.name, q.len);
1632 dir = rpc_create_cache_dir(parent, &q, umode, cd);
1634 cd->u.pipefs.dir = dir;
1636 sunrpc_destroy_cache_detail(cd);
1641 EXPORT_SYMBOL_GPL(sunrpc_cache_register_pipefs);
1643 void sunrpc_cache_unregister_pipefs(struct cache_detail *cd)
1645 rpc_remove_cache_dir(cd->u.pipefs.dir);
1646 cd->u.pipefs.dir = NULL;
1647 sunrpc_destroy_cache_detail(cd);
1649 EXPORT_SYMBOL_GPL(sunrpc_cache_unregister_pipefs);