#include <linux/workqueue.h>
#include <linux/mutex.h>
#include <linux/pagemap.h>
+#include <linux/smp_lock.h>
#include <asm/ioctls.h>
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/cache.h>
h->last_refresh = now;
}
+static inline int cache_is_expired(struct cache_detail *detail, struct cache_head *h)
+{
+ return (h->expiry_time < get_seconds()) ||
+ (detail->flush_time > h->last_refresh);
+}
+
struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
struct cache_head *key, int hash)
{
struct cache_head **head, **hp;
- struct cache_head *new = NULL;
+ struct cache_head *new = NULL, *freeme = NULL;
head = &detail->hash_table[hash];
for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
struct cache_head *tmp = *hp;
if (detail->match(tmp, key)) {
+ if (cache_is_expired(detail, tmp))
+ /* This entry is expired, we will discard it. */
+ break;
cache_get(tmp);
read_unlock(&detail->hash_lock);
return tmp;
for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
struct cache_head *tmp = *hp;
if (detail->match(tmp, key)) {
+ if (cache_is_expired(detail, tmp)) {
+ *hp = tmp->next;
+ tmp->next = NULL;
+ detail->entries --;
+ freeme = tmp;
+ break;
+ }
cache_get(tmp);
write_unlock(&detail->hash_lock);
cache_put(new, detail);
cache_get(new);
write_unlock(&detail->hash_lock);
+ if (freeme)
+ cache_put(freeme, detail);
return new;
}
EXPORT_SYMBOL_GPL(sunrpc_cache_lookup);
-static void queue_loose(struct cache_detail *detail, struct cache_head *ch);
+static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch);
-static int cache_fresh_locked(struct cache_head *head, time_t expiry)
+static void cache_fresh_locked(struct cache_head *head, time_t expiry)
{
head->expiry_time = expiry;
head->last_refresh = get_seconds();
- return !test_and_set_bit(CACHE_VALID, &head->flags);
+ set_bit(CACHE_VALID, &head->flags);
}
static void cache_fresh_unlocked(struct cache_head *head,
- struct cache_detail *detail, int new)
+ struct cache_detail *detail)
{
- if (new)
- cache_revisit_request(head);
if (test_and_clear_bit(CACHE_PENDING, &head->flags)) {
cache_revisit_request(head);
- queue_loose(detail, head);
+ cache_dequeue(detail, head);
}
}
*/
struct cache_head **head;
struct cache_head *tmp;
- int is_new;
if (!test_bit(CACHE_VALID, &old->flags)) {
write_lock(&detail->hash_lock);
set_bit(CACHE_NEGATIVE, &old->flags);
else
detail->update(old, new);
- is_new = cache_fresh_locked(old, new->expiry_time);
+ cache_fresh_locked(old, new->expiry_time);
write_unlock(&detail->hash_lock);
- cache_fresh_unlocked(old, detail, is_new);
+ cache_fresh_unlocked(old, detail);
return old;
}
write_unlock(&detail->hash_lock);
*head = tmp;
detail->entries++;
cache_get(tmp);
- is_new = cache_fresh_locked(tmp, new->expiry_time);
+ cache_fresh_locked(tmp, new->expiry_time);
cache_fresh_locked(old, 0);
write_unlock(&detail->hash_lock);
- cache_fresh_unlocked(tmp, detail, is_new);
- cache_fresh_unlocked(old, detail, 0);
+ cache_fresh_unlocked(tmp, detail);
+ cache_fresh_unlocked(old, detail);
cache_put(old, detail);
return tmp;
}
return cd->cache_upcall(cd, h);
}
+static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h)
+{
+ if (!test_bit(CACHE_VALID, &h->flags))
+ return -EAGAIN;
+ else {
+ /* entry is valid */
+ if (test_bit(CACHE_NEGATIVE, &h->flags))
+ return -ENOENT;
+ else
+ return 0;
+ }
+}
+
/*
* This is the generic cache management routine for all
* the authentication caches.
*
*
* Returns 0 if the cache_head can be used, or cache_puts it and returns
- * -EAGAIN if upcall is pending,
- * -ETIMEDOUT if upcall failed and should be retried,
+ * -EAGAIN if upcall is pending and request has been queued
+ * -ETIMEDOUT if upcall failed or request could not be queue or
+ * upcall completed but item is still invalid (implying that
+ * the cache item has been replaced with a newer one).
* -ENOENT if cache entry was negative
*/
int cache_check(struct cache_detail *detail,
long refresh_age, age;
/* First decide return status as best we can */
- if (!test_bit(CACHE_VALID, &h->flags) ||
- h->expiry_time < get_seconds())
- rv = -EAGAIN;
- else if (detail->flush_time > h->last_refresh)
- rv = -EAGAIN;
- else {
- /* entry is valid */
- if (test_bit(CACHE_NEGATIVE, &h->flags))
- rv = -ENOENT;
- else rv = 0;
- }
+ rv = cache_is_valid(detail, h);
/* now see if we want to start an upcall */
refresh_age = (h->expiry_time - h->last_refresh);
switch (cache_make_upcall(detail, h)) {
case -EINVAL:
clear_bit(CACHE_PENDING, &h->flags);
+ cache_revisit_request(h);
if (rv == -EAGAIN) {
set_bit(CACHE_NEGATIVE, &h->flags);
- cache_fresh_unlocked(h, detail,
- cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY));
+ cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY);
+ cache_fresh_unlocked(h, detail);
rv = -ENOENT;
}
break;
}
}
- if (rv == -EAGAIN)
- if (cache_defer_req(rqstp, h) != 0)
- rv = -ETIMEDOUT;
-
+ if (rv == -EAGAIN) {
+ if (cache_defer_req(rqstp, h) < 0) {
+ /* Request is not deferred */
+ rv = cache_is_valid(detail, h);
+ if (rv == -EAGAIN)
+ rv = -ETIMEDOUT;
+ }
+ }
if (rv)
cache_put(h, detail);
return rv;
/* Ok, now to clean this strand */
cp = & current_detail->hash_table[current_index];
- ch = *cp;
- for (; ch; cp= & ch->next, ch= *cp) {
+ for (ch = *cp ; ch ; cp = & ch->next, ch = *cp) {
if (current_detail->nextcheck > ch->expiry_time)
current_detail->nextcheck = ch->expiry_time+1;
- if (ch->expiry_time >= get_seconds()
- && ch->last_refresh >= current_detail->flush_time
- )
+ if (!cache_is_expired(current_detail, ch))
continue;
- if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
- queue_loose(current_detail, ch);
- if (atomic_read(&ch->ref.refcount) == 1)
- break;
- }
- if (ch) {
*cp = ch->next;
ch->next = NULL;
current_detail->entries--;
rv = 1;
+ break;
}
+
write_unlock(¤t_detail->hash_lock);
d = current_detail;
if (!ch)
current_index ++;
spin_unlock(&cache_list_lock);
- if (ch)
+ if (ch) {
+ if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
+ cache_dequeue(current_detail, ch);
+ cache_revisit_request(ch);
cache_put(ch, d);
+ }
} else
spin_unlock(&cache_list_lock);
static int cache_defer_req(struct cache_req *req, struct cache_head *item)
{
- struct cache_deferred_req *dreq;
+ struct cache_deferred_req *dreq, *discard;
int hash = DFR_HASH(item);
if (cache_defer_cnt >= DFR_MAX) {
* or continue and drop the oldest below
*/
if (net_random()&1)
- return -ETIMEDOUT;
+ return -ENOMEM;
}
dreq = req->defer(req);
if (dreq == NULL)
- return -ETIMEDOUT;
+ return -ENOMEM;
dreq->item = item;
list_add(&dreq->hash, &cache_defer_hash[hash]);
/* it is in, now maybe clean up */
- dreq = NULL;
+ discard = NULL;
if (++cache_defer_cnt > DFR_MAX) {
- dreq = list_entry(cache_defer_list.prev,
- struct cache_deferred_req, recent);
- list_del(&dreq->recent);
- list_del(&dreq->hash);
+ discard = list_entry(cache_defer_list.prev,
+ struct cache_deferred_req, recent);
+ list_del_init(&discard->recent);
+ list_del_init(&discard->hash);
cache_defer_cnt--;
}
spin_unlock(&cache_defer_lock);
- if (dreq) {
+ if (discard)
/* there was one too many */
- dreq->revisit(dreq, 1);
- }
+ discard->revisit(discard, 1);
+
if (!test_bit(CACHE_PENDING, &item->flags)) {
/* must have just been validated... */
cache_revisit_request(item);
+ return -EAGAIN;
}
return 0;
}
dreq = list_entry(lp, struct cache_deferred_req, hash);
lp = lp->next;
if (dreq->item == item) {
- list_del(&dreq->hash);
+ list_del_init(&dreq->hash);
list_move(&dreq->recent, &pending);
cache_defer_cnt--;
}
list_for_each_entry_safe(dreq, tmp, &cache_defer_list, recent) {
if (dreq->owner == owner) {
- list_del(&dreq->hash);
+ list_del_init(&dreq->hash);
list_move(&dreq->recent, &pending);
cache_defer_cnt--;
}
-static void queue_loose(struct cache_detail *detail, struct cache_head *ch)
+static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch)
{
struct cache_queue *cq;
spin_lock(&queue_lock);
if (!cd || !try_module_get(cd->owner))
return -EACCES;
han = __seq_open_private(file, &cache_content_op, sizeof(*han));
- if (han == NULL)
+ if (han == NULL) {
+ module_put(cd->owner);
return -ENOMEM;
+ }
han->cd = cd;
return 0;
return cache_poll(filp, wait, cd);
}
-static int cache_ioctl_procfs(struct inode *inode, struct file *filp,
- unsigned int cmd, unsigned long arg)
+static long cache_ioctl_procfs(struct file *filp,
+ unsigned int cmd, unsigned long arg)
{
+ long ret;
+ struct inode *inode = filp->f_path.dentry->d_inode;
struct cache_detail *cd = PDE(inode)->data;
- return cache_ioctl(inode, filp, cmd, arg, cd);
+ lock_kernel();
+ ret = cache_ioctl(inode, filp, cmd, arg, cd);
+ unlock_kernel();
+
+ return ret;
}
static int cache_open_procfs(struct inode *inode, struct file *filp)
.read = cache_read_procfs,
.write = cache_write_procfs,
.poll = cache_poll_procfs,
- .ioctl = cache_ioctl_procfs, /* for FIONREAD */
+ .unlocked_ioctl = cache_ioctl_procfs, /* for FIONREAD */
.open = cache_open_procfs,
.release = cache_release_procfs,
};