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>
36 #include <linux/smp_lock.h>
38 #define RPCDBG_FACILITY RPCDBG_CACHE
40 static int cache_defer_req(struct cache_req *req, struct cache_head *item);
41 static void cache_revisit_request(struct cache_head *item);
43 static void cache_init(struct cache_head *h)
45 time_t now = get_seconds();
49 h->expiry_time = now + CACHE_NEW_EXPIRY;
50 h->last_refresh = now;
53 struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
54 struct cache_head *key, int hash)
56 struct cache_head **head, **hp;
57 struct cache_head *new = NULL;
59 head = &detail->hash_table[hash];
61 read_lock(&detail->hash_lock);
63 for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
64 struct cache_head *tmp = *hp;
65 if (detail->match(tmp, key)) {
67 read_unlock(&detail->hash_lock);
71 read_unlock(&detail->hash_lock);
72 /* Didn't find anything, insert an empty entry */
74 new = detail->alloc();
77 /* must fully initialise 'new', else
78 * we might get lose if we need to
82 detail->init(new, key);
84 write_lock(&detail->hash_lock);
86 /* check if entry appeared while we slept */
87 for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
88 struct cache_head *tmp = *hp;
89 if (detail->match(tmp, key)) {
91 write_unlock(&detail->hash_lock);
92 cache_put(new, detail);
100 write_unlock(&detail->hash_lock);
104 EXPORT_SYMBOL_GPL(sunrpc_cache_lookup);
107 static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch);
109 static void cache_fresh_locked(struct cache_head *head, time_t expiry)
111 head->expiry_time = expiry;
112 head->last_refresh = get_seconds();
113 set_bit(CACHE_VALID, &head->flags);
116 static void cache_fresh_unlocked(struct cache_head *head,
117 struct cache_detail *detail)
119 if (test_and_clear_bit(CACHE_PENDING, &head->flags)) {
120 cache_revisit_request(head);
121 cache_dequeue(detail, head);
125 struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
126 struct cache_head *new, struct cache_head *old, int hash)
128 /* The 'old' entry is to be replaced by 'new'.
129 * If 'old' is not VALID, we update it directly,
130 * otherwise we need to replace it
132 struct cache_head **head;
133 struct cache_head *tmp;
135 if (!test_bit(CACHE_VALID, &old->flags)) {
136 write_lock(&detail->hash_lock);
137 if (!test_bit(CACHE_VALID, &old->flags)) {
138 if (test_bit(CACHE_NEGATIVE, &new->flags))
139 set_bit(CACHE_NEGATIVE, &old->flags);
141 detail->update(old, new);
142 cache_fresh_locked(old, new->expiry_time);
143 write_unlock(&detail->hash_lock);
144 cache_fresh_unlocked(old, detail);
147 write_unlock(&detail->hash_lock);
149 /* We need to insert a new entry */
150 tmp = detail->alloc();
152 cache_put(old, detail);
156 detail->init(tmp, old);
157 head = &detail->hash_table[hash];
159 write_lock(&detail->hash_lock);
160 if (test_bit(CACHE_NEGATIVE, &new->flags))
161 set_bit(CACHE_NEGATIVE, &tmp->flags);
163 detail->update(tmp, new);
168 cache_fresh_locked(tmp, new->expiry_time);
169 cache_fresh_locked(old, 0);
170 write_unlock(&detail->hash_lock);
171 cache_fresh_unlocked(tmp, detail);
172 cache_fresh_unlocked(old, detail);
173 cache_put(old, detail);
176 EXPORT_SYMBOL_GPL(sunrpc_cache_update);
178 static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
180 if (!cd->cache_upcall)
182 return cd->cache_upcall(cd, h);
185 static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h)
187 if (!test_bit(CACHE_VALID, &h->flags) ||
188 h->expiry_time < get_seconds())
190 else if (detail->flush_time > h->last_refresh)
194 if (test_bit(CACHE_NEGATIVE, &h->flags))
202 * This is the generic cache management routine for all
203 * the authentication caches.
204 * It checks the currency of a cache item and will (later)
205 * initiate an upcall to fill it if needed.
208 * Returns 0 if the cache_head can be used, or cache_puts it and returns
209 * -EAGAIN if upcall is pending and request has been queued
210 * -ETIMEDOUT if upcall failed or request could not be queue or
211 * upcall completed but item is still invalid (implying that
212 * the cache item has been replaced with a newer one).
213 * -ENOENT if cache entry was negative
215 int cache_check(struct cache_detail *detail,
216 struct cache_head *h, struct cache_req *rqstp)
219 long refresh_age, age;
221 /* First decide return status as best we can */
222 rv = cache_is_valid(detail, h);
224 /* now see if we want to start an upcall */
225 refresh_age = (h->expiry_time - h->last_refresh);
226 age = get_seconds() - h->last_refresh;
231 } else if (rv == -EAGAIN || age > refresh_age/2) {
232 dprintk("RPC: Want update, refage=%ld, age=%ld\n",
234 if (!test_and_set_bit(CACHE_PENDING, &h->flags)) {
235 switch (cache_make_upcall(detail, h)) {
237 clear_bit(CACHE_PENDING, &h->flags);
238 cache_revisit_request(h);
240 set_bit(CACHE_NEGATIVE, &h->flags);
241 cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY);
242 cache_fresh_unlocked(h, detail);
248 clear_bit(CACHE_PENDING, &h->flags);
249 cache_revisit_request(h);
256 if (cache_defer_req(rqstp, h) < 0) {
257 /* Request is not deferred */
258 rv = cache_is_valid(detail, h);
264 cache_put(h, detail);
267 EXPORT_SYMBOL_GPL(cache_check);
270 * caches need to be periodically cleaned.
271 * For this we maintain a list of cache_detail and
272 * a current pointer into that list and into the table
275 * Each time clean_cache is called it finds the next non-empty entry
276 * in the current table and walks the list in that entry
277 * looking for entries that can be removed.
279 * An entry gets removed if:
280 * - The expiry is before current time
281 * - The last_refresh time is before the flush_time for that cache
283 * later we might drop old entries with non-NEVER expiry if that table
284 * is getting 'full' for some definition of 'full'
286 * The question of "how often to scan a table" is an interesting one
287 * and is answered in part by the use of the "nextcheck" field in the
289 * When a scan of a table begins, the nextcheck field is set to a time
290 * that is well into the future.
291 * While scanning, if an expiry time is found that is earlier than the
292 * current nextcheck time, nextcheck is set to that expiry time.
293 * If the flush_time is ever set to a time earlier than the nextcheck
294 * time, the nextcheck time is then set to that flush_time.
296 * A table is then only scanned if the current time is at least
297 * the nextcheck time.
301 static LIST_HEAD(cache_list);
302 static DEFINE_SPINLOCK(cache_list_lock);
303 static struct cache_detail *current_detail;
304 static int current_index;
306 static void do_cache_clean(struct work_struct *work);
307 static DECLARE_DELAYED_WORK(cache_cleaner, do_cache_clean);
309 static void sunrpc_init_cache_detail(struct cache_detail *cd)
311 rwlock_init(&cd->hash_lock);
312 INIT_LIST_HEAD(&cd->queue);
313 spin_lock(&cache_list_lock);
316 atomic_set(&cd->readers, 0);
319 list_add(&cd->others, &cache_list);
320 spin_unlock(&cache_list_lock);
322 /* start the cleaning process */
323 schedule_delayed_work(&cache_cleaner, 0);
326 static void sunrpc_destroy_cache_detail(struct cache_detail *cd)
329 spin_lock(&cache_list_lock);
330 write_lock(&cd->hash_lock);
331 if (cd->entries || atomic_read(&cd->inuse)) {
332 write_unlock(&cd->hash_lock);
333 spin_unlock(&cache_list_lock);
336 if (current_detail == cd)
337 current_detail = NULL;
338 list_del_init(&cd->others);
339 write_unlock(&cd->hash_lock);
340 spin_unlock(&cache_list_lock);
341 if (list_empty(&cache_list)) {
342 /* module must be being unloaded so its safe to kill the worker */
343 cancel_delayed_work_sync(&cache_cleaner);
347 printk(KERN_ERR "nfsd: failed to unregister %s cache\n", cd->name);
350 /* clean cache tries to find something to clean
352 * It returns 1 if it cleaned something,
353 * 0 if it didn't find anything this time
354 * -1 if it fell off the end of the list.
356 static int cache_clean(void)
359 struct list_head *next;
361 spin_lock(&cache_list_lock);
363 /* find a suitable table if we don't already have one */
364 while (current_detail == NULL ||
365 current_index >= current_detail->hash_size) {
367 next = current_detail->others.next;
369 next = cache_list.next;
370 if (next == &cache_list) {
371 current_detail = NULL;
372 spin_unlock(&cache_list_lock);
375 current_detail = list_entry(next, struct cache_detail, others);
376 if (current_detail->nextcheck > get_seconds())
377 current_index = current_detail->hash_size;
380 current_detail->nextcheck = get_seconds()+30*60;
384 /* find a non-empty bucket in the table */
385 while (current_detail &&
386 current_index < current_detail->hash_size &&
387 current_detail->hash_table[current_index] == NULL)
390 /* find a cleanable entry in the bucket and clean it, or set to next bucket */
392 if (current_detail && current_index < current_detail->hash_size) {
393 struct cache_head *ch, **cp;
394 struct cache_detail *d;
396 write_lock(¤t_detail->hash_lock);
398 /* Ok, now to clean this strand */
400 cp = & current_detail->hash_table[current_index];
402 for (; ch; cp= & ch->next, ch= *cp) {
403 if (current_detail->nextcheck > ch->expiry_time)
404 current_detail->nextcheck = ch->expiry_time+1;
405 if (ch->expiry_time >= get_seconds() &&
406 ch->last_refresh >= current_detail->flush_time)
408 if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
409 cache_dequeue(current_detail, ch);
411 if (atomic_read(&ch->ref.refcount) == 1)
417 current_detail->entries--;
420 write_unlock(¤t_detail->hash_lock);
424 spin_unlock(&cache_list_lock);
426 cache_revisit_request(ch);
430 spin_unlock(&cache_list_lock);
436 * We want to regularly clean the cache, so we need to schedule some work ...
438 static void do_cache_clean(struct work_struct *work)
441 if (cache_clean() == -1)
442 delay = round_jiffies_relative(30*HZ);
444 if (list_empty(&cache_list))
448 schedule_delayed_work(&cache_cleaner, delay);
453 * Clean all caches promptly. This just calls cache_clean
454 * repeatedly until we are sure that every cache has had a chance to
457 void cache_flush(void)
459 while (cache_clean() != -1)
461 while (cache_clean() != -1)
464 EXPORT_SYMBOL_GPL(cache_flush);
466 void cache_purge(struct cache_detail *detail)
468 detail->flush_time = LONG_MAX;
469 detail->nextcheck = get_seconds();
471 detail->flush_time = 1;
473 EXPORT_SYMBOL_GPL(cache_purge);
477 * Deferral and Revisiting of Requests.
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
491 #define DFR_HASHSIZE (PAGE_SIZE/sizeof(struct list_head))
492 #define DFR_HASH(item) ((((long)item)>>4 ^ (((long)item)>>13)) % DFR_HASHSIZE)
494 #define DFR_MAX 300 /* ??? */
496 static DEFINE_SPINLOCK(cache_defer_lock);
497 static LIST_HEAD(cache_defer_list);
498 static struct list_head cache_defer_hash[DFR_HASHSIZE];
499 static int cache_defer_cnt;
501 static int cache_defer_req(struct cache_req *req, struct cache_head *item)
503 struct cache_deferred_req *dreq, *discard;
504 int hash = DFR_HASH(item);
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
513 dreq = req->defer(req);
519 spin_lock(&cache_defer_lock);
521 list_add(&dreq->recent, &cache_defer_list);
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]);
527 /* it is in, now maybe clean up */
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);
536 spin_unlock(&cache_defer_lock);
539 /* there was one too many */
540 discard->revisit(discard, 1);
542 if (!test_bit(CACHE_PENDING, &item->flags)) {
543 /* must have just been validated... */
544 cache_revisit_request(item);
550 static void cache_revisit_request(struct cache_head *item)
552 struct cache_deferred_req *dreq;
553 struct list_head pending;
555 struct list_head *lp;
556 int hash = DFR_HASH(item);
558 INIT_LIST_HEAD(&pending);
559 spin_lock(&cache_defer_lock);
561 lp = cache_defer_hash[hash].next;
563 while (lp != &cache_defer_hash[hash]) {
564 dreq = list_entry(lp, struct cache_deferred_req, hash);
566 if (dreq->item == item) {
567 list_del_init(&dreq->hash);
568 list_move(&dreq->recent, &pending);
573 spin_unlock(&cache_defer_lock);
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);
582 void cache_clean_deferred(void *owner)
584 struct cache_deferred_req *dreq, *tmp;
585 struct list_head pending;
588 INIT_LIST_HEAD(&pending);
589 spin_lock(&cache_defer_lock);
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);
598 spin_unlock(&cache_defer_lock);
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);
608 * communicate with user-space
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.
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.
623 static DEFINE_SPINLOCK(queue_lock);
624 static DEFINE_MUTEX(queue_io_mutex);
627 struct list_head list;
628 int reader; /* if 0, then request */
630 struct cache_request {
631 struct cache_queue q;
632 struct cache_head *item;
637 struct cache_reader {
638 struct cache_queue q;
639 int offset; /* if non-0, we have a refcnt on next request */
642 static ssize_t cache_read(struct file *filp, char __user *buf, size_t count,
643 loff_t *ppos, struct cache_detail *cd)
645 struct cache_reader *rp = filp->private_data;
646 struct cache_request *rq;
647 struct inode *inode = filp->f_path.dentry->d_inode;
653 mutex_lock(&inode->i_mutex); /* protect against multiple concurrent
654 * readers on this file */
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)
661 struct list_head *next = rp->q.list.next;
662 list_move(&rp->q.list, next);
664 if (rp->q.list.next == &cd->queue) {
665 spin_unlock(&queue_lock);
666 mutex_unlock(&inode->i_mutex);
670 rq = container_of(rp->q.list.next, struct cache_request, q.list);
671 BUG_ON(rq->q.reader);
674 spin_unlock(&queue_lock);
676 if (rp->offset == 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) {
678 spin_lock(&queue_lock);
679 list_move(&rp->q.list, &rq->q.list);
680 spin_unlock(&queue_lock);
682 if (rp->offset + count > rq->len)
683 count = rq->len - rp->offset;
685 if (copy_to_user(buf, rq->buf + rp->offset, count))
688 if (rp->offset >= rq->len) {
690 spin_lock(&queue_lock);
691 list_move(&rp->q.list, &rq->q.list);
692 spin_unlock(&queue_lock);
697 if (rp->offset == 0) {
698 /* need to release rq */
699 spin_lock(&queue_lock);
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);
709 spin_unlock(&queue_lock);
713 mutex_unlock(&inode->i_mutex);
714 return err ? err : count;
717 static ssize_t cache_do_downcall(char *kaddr, const char __user *buf,
718 size_t count, struct cache_detail *cd)
722 if (copy_from_user(kaddr, buf, count))
725 ret = cd->cache_parse(cd, kaddr, count);
731 static ssize_t cache_slow_downcall(const char __user *buf,
732 size_t count, struct cache_detail *cd)
734 static char write_buf[8192]; /* protected by queue_io_mutex */
735 ssize_t ret = -EINVAL;
737 if (count >= sizeof(write_buf))
739 mutex_lock(&queue_io_mutex);
740 ret = cache_do_downcall(write_buf, buf, count, cd);
741 mutex_unlock(&queue_io_mutex);
746 static ssize_t cache_downcall(struct address_space *mapping,
747 const char __user *buf,
748 size_t count, struct cache_detail *cd)
752 ssize_t ret = -ENOMEM;
754 if (count >= PAGE_CACHE_SIZE)
757 page = find_or_create_page(mapping, 0, GFP_KERNEL);
762 ret = cache_do_downcall(kaddr, buf, count, cd);
765 page_cache_release(page);
768 return cache_slow_downcall(buf, count, cd);
771 static ssize_t cache_write(struct file *filp, const char __user *buf,
772 size_t count, loff_t *ppos,
773 struct cache_detail *cd)
775 struct address_space *mapping = filp->f_mapping;
776 struct inode *inode = filp->f_path.dentry->d_inode;
777 ssize_t ret = -EINVAL;
779 if (!cd->cache_parse)
782 mutex_lock(&inode->i_mutex);
783 ret = cache_downcall(mapping, buf, count, cd);
784 mutex_unlock(&inode->i_mutex);
789 static DECLARE_WAIT_QUEUE_HEAD(queue_wait);
791 static unsigned int cache_poll(struct file *filp, poll_table *wait,
792 struct cache_detail *cd)
795 struct cache_reader *rp = filp->private_data;
796 struct cache_queue *cq;
798 poll_wait(filp, &queue_wait, wait);
800 /* alway allow write */
801 mask = POLL_OUT | POLLWRNORM;
806 spin_lock(&queue_lock);
808 for (cq= &rp->q; &cq->list != &cd->queue;
809 cq = list_entry(cq->list.next, struct cache_queue, list))
811 mask |= POLLIN | POLLRDNORM;
814 spin_unlock(&queue_lock);
818 static int cache_ioctl(struct inode *ino, struct file *filp,
819 unsigned int cmd, unsigned long arg,
820 struct cache_detail *cd)
823 struct cache_reader *rp = filp->private_data;
824 struct cache_queue *cq;
826 if (cmd != FIONREAD || !rp)
829 spin_lock(&queue_lock);
831 /* only find the length remaining in current request,
832 * or the length of the next request
834 for (cq= &rp->q; &cq->list != &cd->queue;
835 cq = list_entry(cq->list.next, struct cache_queue, list))
837 struct cache_request *cr =
838 container_of(cq, struct cache_request, q);
839 len = cr->len - rp->offset;
842 spin_unlock(&queue_lock);
844 return put_user(len, (int __user *)arg);
847 static int cache_open(struct inode *inode, struct file *filp,
848 struct cache_detail *cd)
850 struct cache_reader *rp = NULL;
852 if (!cd || !try_module_get(cd->owner))
854 nonseekable_open(inode, filp);
855 if (filp->f_mode & FMODE_READ) {
856 rp = kmalloc(sizeof(*rp), GFP_KERNEL);
861 atomic_inc(&cd->readers);
862 spin_lock(&queue_lock);
863 list_add(&rp->q.list, &cd->queue);
864 spin_unlock(&queue_lock);
866 filp->private_data = rp;
870 static int cache_release(struct inode *inode, struct file *filp,
871 struct cache_detail *cd)
873 struct cache_reader *rp = filp->private_data;
876 spin_lock(&queue_lock);
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))
882 container_of(cq, struct cache_request, q)
888 list_del(&rp->q.list);
889 spin_unlock(&queue_lock);
891 filp->private_data = NULL;
894 cd->last_close = get_seconds();
895 atomic_dec(&cd->readers);
897 module_put(cd->owner);
903 static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch)
905 struct cache_queue *cq;
906 spin_lock(&queue_lock);
907 list_for_each_entry(cq, &detail->queue, list)
909 struct cache_request *cr = container_of(cq, struct cache_request, q);
912 if (cr->readers != 0)
914 list_del(&cr->q.list);
915 spin_unlock(&queue_lock);
916 cache_put(cr->item, detail);
921 spin_unlock(&queue_lock);
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.
933 void qword_add(char **bpp, int *lp, char *str)
941 while ((c=*str++) && len)
949 *bp++ = '0' + ((c & 0300)>>6);
950 *bp++ = '0' + ((c & 0070)>>3);
951 *bp++ = '0' + ((c & 0007)>>0);
959 if (c || len <1) len = -1;
967 EXPORT_SYMBOL_GPL(qword_add);
969 void qword_addhex(char **bpp, int *lp, char *buf, int blen)
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);
988 if (blen || len<1) len = -1;
996 EXPORT_SYMBOL_GPL(qword_addhex);
998 static void warn_no_listener(struct cache_detail *detail)
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);
1008 * register an upcall request to user-space and queue it up for read() by the
1011 * Each request is at most one page long.
1013 int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h,
1014 void (*cache_request)(struct cache_detail *,
1015 struct cache_head *,
1021 struct cache_request *crq;
1025 if (atomic_read(&detail->readers) == 0 &&
1026 detail->last_close < get_seconds() - 30) {
1027 warn_no_listener(detail);
1031 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1035 crq = kmalloc(sizeof (*crq), GFP_KERNEL);
1041 bp = buf; len = PAGE_SIZE;
1043 cache_request(detail, h, &bp, &len);
1051 crq->item = cache_get(h);
1053 crq->len = PAGE_SIZE - len;
1055 spin_lock(&queue_lock);
1056 list_add_tail(&crq->q.list, &detail->queue);
1057 spin_unlock(&queue_lock);
1058 wake_up(&queue_wait);
1061 EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall);
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
1070 * reply cachename expiry key ... content....
1072 * key and content are both parsed by cache
1075 #define isodigit(c) (isdigit(c) && c <= '7')
1076 int qword_get(char **bpp, char *dest, int bufsize)
1078 /* return bytes copied, or -1 on error */
1082 while (*bp == ' ') bp++;
1084 if (bp[0] == '\\' && bp[1] == 'x') {
1087 while (isxdigit(bp[0]) && isxdigit(bp[1]) && len < bufsize) {
1088 int byte = isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10;
1091 byte |= isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10;
1097 /* text with \nnn octal quoting */
1098 while (*bp != ' ' && *bp != '\n' && *bp && len < bufsize-1) {
1100 isodigit(bp[1]) && (bp[1] <= '3') &&
1103 int byte = (*++bp -'0');
1105 byte = (byte << 3) | (*bp++ - '0');
1106 byte = (byte << 3) | (*bp++ - '0');
1116 if (*bp != ' ' && *bp != '\n' && *bp != '\0')
1118 while (*bp == ' ') bp++;
1123 EXPORT_SYMBOL_GPL(qword_get);
1127 * support /proc/sunrpc/cache/$CACHENAME/content
1129 * We call ->cache_show passing NULL for the item to
1130 * get a header, then pass each real item in the cache
1134 struct cache_detail *cd;
1137 static void *c_start(struct seq_file *m, loff_t *pos)
1138 __acquires(cd->hash_lock)
1141 unsigned hash, entry;
1142 struct cache_head *ch;
1143 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1146 read_lock(&cd->hash_lock);
1148 return SEQ_START_TOKEN;
1150 entry = n & ((1LL<<32) - 1);
1152 for (ch=cd->hash_table[hash]; ch; ch=ch->next)
1155 n &= ~((1LL<<32) - 1);
1159 } while(hash < cd->hash_size &&
1160 cd->hash_table[hash]==NULL);
1161 if (hash >= cd->hash_size)
1164 return cd->hash_table[hash];
1167 static void *c_next(struct seq_file *m, void *p, loff_t *pos)
1169 struct cache_head *ch = p;
1170 int hash = (*pos >> 32);
1171 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1173 if (p == SEQ_START_TOKEN)
1175 else if (ch->next == NULL) {
1182 *pos &= ~((1LL<<32) - 1);
1183 while (hash < cd->hash_size &&
1184 cd->hash_table[hash] == NULL) {
1188 if (hash >= cd->hash_size)
1191 return cd->hash_table[hash];
1194 static void c_stop(struct seq_file *m, void *p)
1195 __releases(cd->hash_lock)
1197 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1198 read_unlock(&cd->hash_lock);
1201 static int c_show(struct seq_file *m, void *p)
1203 struct cache_head *cp = p;
1204 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1206 if (p == SEQ_START_TOKEN)
1207 return cd->cache_show(m, cd, NULL);
1210 seq_printf(m, "# expiry=%ld refcnt=%d flags=%lx\n",
1211 cp->expiry_time, atomic_read(&cp->ref.refcount), cp->flags);
1213 if (cache_check(cd, cp, NULL))
1214 /* cache_check does a cache_put on failure */
1215 seq_printf(m, "# ");
1219 return cd->cache_show(m, cd, cp);
1222 static const struct seq_operations cache_content_op = {
1229 static int content_open(struct inode *inode, struct file *file,
1230 struct cache_detail *cd)
1234 if (!cd || !try_module_get(cd->owner))
1236 han = __seq_open_private(file, &cache_content_op, sizeof(*han));
1244 static int content_release(struct inode *inode, struct file *file,
1245 struct cache_detail *cd)
1247 int ret = seq_release_private(inode, file);
1248 module_put(cd->owner);
1252 static int open_flush(struct inode *inode, struct file *file,
1253 struct cache_detail *cd)
1255 if (!cd || !try_module_get(cd->owner))
1257 return nonseekable_open(inode, file);
1260 static int release_flush(struct inode *inode, struct file *file,
1261 struct cache_detail *cd)
1263 module_put(cd->owner);
1267 static ssize_t read_flush(struct file *file, char __user *buf,
1268 size_t count, loff_t *ppos,
1269 struct cache_detail *cd)
1272 unsigned long p = *ppos;
1275 sprintf(tbuf, "%lu\n", cd->flush_time);
1282 if (copy_to_user(buf, (void*)(tbuf+p), len))
1288 static ssize_t write_flush(struct file *file, const char __user *buf,
1289 size_t count, loff_t *ppos,
1290 struct cache_detail *cd)
1295 if (*ppos || count > sizeof(tbuf)-1)
1297 if (copy_from_user(tbuf, buf, count))
1300 flushtime = simple_strtoul(tbuf, &ep, 0);
1301 if (*ep && *ep != '\n')
1304 cd->flush_time = flushtime;
1305 cd->nextcheck = get_seconds();
1312 static ssize_t cache_read_procfs(struct file *filp, char __user *buf,
1313 size_t count, loff_t *ppos)
1315 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1317 return cache_read(filp, buf, count, ppos, cd);
1320 static ssize_t cache_write_procfs(struct file *filp, const char __user *buf,
1321 size_t count, loff_t *ppos)
1323 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1325 return cache_write(filp, buf, count, ppos, cd);
1328 static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait)
1330 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1332 return cache_poll(filp, wait, cd);
1335 static int cache_ioctl_procfs(struct inode *inode, struct file *filp,
1336 unsigned int cmd, unsigned long arg)
1338 struct cache_detail *cd = PDE(inode)->data;
1340 return cache_ioctl(inode, filp, cmd, arg, cd);
1343 static int cache_open_procfs(struct inode *inode, struct file *filp)
1345 struct cache_detail *cd = PDE(inode)->data;
1347 return cache_open(inode, filp, cd);
1350 static int cache_release_procfs(struct inode *inode, struct file *filp)
1352 struct cache_detail *cd = PDE(inode)->data;
1354 return cache_release(inode, filp, cd);
1357 static 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,
1368 static int content_open_procfs(struct inode *inode, struct file *filp)
1370 struct cache_detail *cd = PDE(inode)->data;
1372 return content_open(inode, filp, cd);
1375 static int content_release_procfs(struct inode *inode, struct file *filp)
1377 struct cache_detail *cd = PDE(inode)->data;
1379 return content_release(inode, filp, cd);
1382 static const struct file_operations content_file_operations_procfs = {
1383 .open = content_open_procfs,
1385 .llseek = seq_lseek,
1386 .release = content_release_procfs,
1389 static int open_flush_procfs(struct inode *inode, struct file *filp)
1391 struct cache_detail *cd = PDE(inode)->data;
1393 return open_flush(inode, filp, cd);
1396 static int release_flush_procfs(struct inode *inode, struct file *filp)
1398 struct cache_detail *cd = PDE(inode)->data;
1400 return release_flush(inode, filp, cd);
1403 static ssize_t read_flush_procfs(struct file *filp, char __user *buf,
1404 size_t count, loff_t *ppos)
1406 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1408 return read_flush(filp, buf, count, ppos, cd);
1411 static ssize_t write_flush_procfs(struct file *filp,
1412 const char __user *buf,
1413 size_t count, loff_t *ppos)
1415 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1417 return write_flush(filp, buf, count, ppos, cd);
1420 static 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,
1427 static void remove_cache_proc_entries(struct cache_detail *cd)
1429 if (cd->u.procfs.proc_ent == NULL)
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);
1441 #ifdef CONFIG_PROC_FS
1442 static int create_cache_proc_entries(struct cache_detail *cd)
1444 struct proc_dir_entry *p;
1446 cd->u.procfs.proc_ent = proc_mkdir(cd->name, proc_net_rpc);
1447 if (cd->u.procfs.proc_ent == NULL)
1449 cd->u.procfs.channel_ent = NULL;
1450 cd->u.procfs.content_ent = NULL;
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;
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;
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;
1477 remove_cache_proc_entries(cd);
1480 #else /* CONFIG_PROC_FS */
1481 static int create_cache_proc_entries(struct cache_detail *cd)
1487 int cache_register(struct cache_detail *cd)
1491 sunrpc_init_cache_detail(cd);
1492 ret = create_cache_proc_entries(cd);
1494 sunrpc_destroy_cache_detail(cd);
1497 EXPORT_SYMBOL_GPL(cache_register);
1499 void cache_unregister(struct cache_detail *cd)
1501 remove_cache_proc_entries(cd);
1502 sunrpc_destroy_cache_detail(cd);
1504 EXPORT_SYMBOL_GPL(cache_unregister);
1506 static ssize_t cache_read_pipefs(struct file *filp, char __user *buf,
1507 size_t count, loff_t *ppos)
1509 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1511 return cache_read(filp, buf, count, ppos, cd);
1514 static ssize_t cache_write_pipefs(struct file *filp, const char __user *buf,
1515 size_t count, loff_t *ppos)
1517 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1519 return cache_write(filp, buf, count, ppos, cd);
1522 static unsigned int cache_poll_pipefs(struct file *filp, poll_table *wait)
1524 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1526 return cache_poll(filp, wait, cd);
1529 static long cache_ioctl_pipefs(struct file *filp,
1530 unsigned int cmd, unsigned long arg)
1532 struct inode *inode = filp->f_dentry->d_inode;
1533 struct cache_detail *cd = RPC_I(inode)->private;
1537 ret = cache_ioctl(inode, filp, cmd, arg, cd);
1543 static int cache_open_pipefs(struct inode *inode, struct file *filp)
1545 struct cache_detail *cd = RPC_I(inode)->private;
1547 return cache_open(inode, filp, cd);
1550 static int cache_release_pipefs(struct inode *inode, struct file *filp)
1552 struct cache_detail *cd = RPC_I(inode)->private;
1554 return cache_release(inode, filp, cd);
1557 const struct file_operations cache_file_operations_pipefs = {
1558 .owner = THIS_MODULE,
1559 .llseek = no_llseek,
1560 .read = cache_read_pipefs,
1561 .write = cache_write_pipefs,
1562 .poll = cache_poll_pipefs,
1563 .unlocked_ioctl = cache_ioctl_pipefs, /* for FIONREAD */
1564 .open = cache_open_pipefs,
1565 .release = cache_release_pipefs,
1568 static int content_open_pipefs(struct inode *inode, struct file *filp)
1570 struct cache_detail *cd = RPC_I(inode)->private;
1572 return content_open(inode, filp, cd);
1575 static int content_release_pipefs(struct inode *inode, struct file *filp)
1577 struct cache_detail *cd = RPC_I(inode)->private;
1579 return content_release(inode, filp, cd);
1582 const struct file_operations content_file_operations_pipefs = {
1583 .open = content_open_pipefs,
1585 .llseek = seq_lseek,
1586 .release = content_release_pipefs,
1589 static int open_flush_pipefs(struct inode *inode, struct file *filp)
1591 struct cache_detail *cd = RPC_I(inode)->private;
1593 return open_flush(inode, filp, cd);
1596 static int release_flush_pipefs(struct inode *inode, struct file *filp)
1598 struct cache_detail *cd = RPC_I(inode)->private;
1600 return release_flush(inode, filp, cd);
1603 static ssize_t read_flush_pipefs(struct file *filp, char __user *buf,
1604 size_t count, loff_t *ppos)
1606 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1608 return read_flush(filp, buf, count, ppos, cd);
1611 static ssize_t write_flush_pipefs(struct file *filp,
1612 const char __user *buf,
1613 size_t count, loff_t *ppos)
1615 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1617 return write_flush(filp, buf, count, ppos, cd);
1620 const struct file_operations cache_flush_operations_pipefs = {
1621 .open = open_flush_pipefs,
1622 .read = read_flush_pipefs,
1623 .write = write_flush_pipefs,
1624 .release = release_flush_pipefs,
1627 int sunrpc_cache_register_pipefs(struct dentry *parent,
1628 const char *name, mode_t umode,
1629 struct cache_detail *cd)
1635 sunrpc_init_cache_detail(cd);
1637 q.len = strlen(name);
1638 q.hash = full_name_hash(q.name, q.len);
1639 dir = rpc_create_cache_dir(parent, &q, umode, cd);
1641 cd->u.pipefs.dir = dir;
1643 sunrpc_destroy_cache_detail(cd);
1648 EXPORT_SYMBOL_GPL(sunrpc_cache_register_pipefs);
1650 void sunrpc_cache_unregister_pipefs(struct cache_detail *cd)
1652 rpc_remove_cache_dir(cd->u.pipefs.dir);
1653 cd->u.pipefs.dir = NULL;
1654 sunrpc_destroy_cache_detail(cd);
1656 EXPORT_SYMBOL_GPL(sunrpc_cache_unregister_pipefs);