1 files changed, 61 insertions, 48 deletions

diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 45cdaff9b361..d6eee291a0e2 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -103,23 +103,21 @@ struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
 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);
         }
 }
 
@@ -132,7 +130,6 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
          */
         struct cache_head **head;
         struct cache_head *tmp;
-        int is_new;
 
         if (!test_bit(CACHE_VALID, &old->flags)) {
                 write_lock(&detail->hash_lock);
@@ -141,9 +138,9 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
                                 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);
@@ -167,11 +164,11 @@ struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
         *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;
 }
@@ -184,6 +181,22 @@ static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
         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) ||
+            h->expiry_time < get_seconds())
+                return -EAGAIN;
+        else if (detail->flush_time > h->last_refresh)
+                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.
@@ -192,8 +205,10 @@ static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
  *
  *
  * 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,
@@ -203,17 +218,7 @@ 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);
@@ -229,10 +234,11 @@ int cache_check(struct cache_detail *detail,
                         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;
@@ -245,10 +251,14 @@ int cache_check(struct cache_detail *detail,
                 }
         }
 
-        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;
@@ -396,7 +406,7 @@ static int cache_clean(void)
                                 )
                                 continue;
                         if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
-                                queue_loose(current_detail, ch);
+                                cache_dequeue(current_detail, ch);
 
                         if (atomic_read(&ch->ref.refcount) == 1)
                                 break;
@@ -412,8 +422,10 @@ static int cache_clean(void)
                 if (!ch)
                         current_index ++;
                 spin_unlock(&cache_list_lock);
-                if (ch)
+                if (ch) {
+                        cache_revisit_request(ch);
                         cache_put(ch, d);
+                }
         } else
                 spin_unlock(&cache_list_lock);
 
@@ -488,7 +500,7 @@ static int cache_defer_cnt;
 
 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) {
@@ -496,11 +508,11 @@ static int cache_defer_req(struct cache_req *req, struct cache_head *item)
                  * 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;
 
@@ -513,23 +525,24 @@ static int cache_defer_req(struct cache_req *req, struct cache_head *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;
 }
@@ -551,7 +564,7 @@ static void cache_revisit_request(struct cache_head *item)
                         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--;
                         }
@@ -577,7 +590,7 @@ void cache_clean_deferred(void *owner)
 
         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--;
                 }
@@ -887,7 +900,7 @@ static int cache_release(struct inode *inode, struct file *filp,
 
 
 
-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);