1 files changed, 41 insertions, 25 deletions

diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 45cdaff9b361..ade8a7e99cd3 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -103,7 +103,7 @@ 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)
 {
@@ -119,7 +119,7 @@ static void cache_fresh_unlocked(struct cache_head *head,
                 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);
         }
 }
 
@@ -184,6 +184,22 @@ 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 +208,10 @@ 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 +221,7 @@ 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);
@@ -229,6 +237,7 @@ 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,
@@ -245,10 +254,14 @@ 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 +409,7 @@ 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 +425,10 @@ 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);
 
@@ -496,11 +511,11 @@ 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 0;
         }
         dreq = req->defer(req);
         if (dreq == NULL)
-                return -ETIMEDOUT;
+                return 0;
 
         dreq->item = item;
 
@@ -530,8 +545,9 @@ static int cache_defer_req(struct cache_req *req, struct cache_head *item)
         if (!test_bit(CACHE_PENDING, &item->flags)) {
                 /* must have just been validated... */
                 cache_revisit_request(item);
+                return 0;
         }
-        return 0;
+        return 1;
 }
 
 static void cache_revisit_request(struct cache_head *item)
@@ -887,7 +903,7 @@ 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);