1 files changed, 29 insertions, 22 deletions

diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 39a4112faf54..25d58e766014 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -196,9 +196,9 @@ EXPORT_SYMBOL_GPL(sunrpc_cache_update);
 
 static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
 {
-        if (!cd->cache_upcall)
-                return -EINVAL;
-        return cd->cache_upcall(cd, h);
+        if (cd->cache_upcall)
+                return cd->cache_upcall(cd, h);
+        return sunrpc_cache_pipe_upcall(cd, h);
 }
 
 static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h)
@@ -750,6 +750,18 @@ struct cache_reader {
         int                     offset; /* if non-0, we have a refcnt on next request */
 };
 
+static int cache_request(struct cache_detail *detail,
+                               struct cache_request *crq)
+{
+        char *bp = crq->buf;
+        int len = PAGE_SIZE;
+
+        detail->cache_request(detail, crq->item, &bp, &len);
+        if (len < 0)
+                return -EAGAIN;
+        return PAGE_SIZE - len;
+}
+
 static ssize_t cache_read(struct file *filp, char __user *buf, size_t count,
                           loff_t *ppos, struct cache_detail *cd)
 {
@@ -784,6 +796,13 @@ static ssize_t cache_read(struct file *filp, char __user *buf, size_t count,
                 rq->readers++;
         spin_unlock(&queue_lock);
 
+        if (rq->len == 0) {
+                err = cache_request(cd, rq);
+                if (err < 0)
+                        goto out;
+                rq->len = err;
+        }
+
         if (rp->offset == 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) {
                 err = -EAGAIN;
                 spin_lock(&queue_lock);
@@ -1140,17 +1159,14 @@ static bool cache_listeners_exist(struct cache_detail *detail)
  *
  * Each request is at most one page long.
  */
-int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h,
-                void (*cache_request)(struct cache_detail *,
-                                      struct cache_head *,
-                                      char **,
-                                      int *))
+int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h)
 {
 
         char *buf;
         struct cache_request *crq;
-        char *bp;
-        int len;
+
+        if (!detail->cache_request)
+                return -EINVAL;
 
         if (!cache_listeners_exist(detail)) {
                 warn_no_listener(detail);
@@ -1167,19 +1183,10 @@ int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h,
                 return -EAGAIN;
         }
 
-        bp = buf; len = PAGE_SIZE;
-
-        cache_request(detail, h, &bp, &len);
-
-        if (len < 0) {
-                kfree(buf);
-                kfree(crq);
-                return -EAGAIN;
-        }
         crq->q.reader = 0;
         crq->item = cache_get(h);
         crq->buf = buf;
-        crq->len = PAGE_SIZE - len;
+        crq->len = 0;
         crq->readers = 0;
         spin_lock(&queue_lock);
         list_add_tail(&crq->q.list, &detail->queue);
@@ -1605,7 +1612,7 @@ static int create_cache_proc_entries(struct cache_detail *cd, struct net *net)
         if (p == NULL)
                 goto out_nomem;
 
-        if (cd->cache_upcall || cd->cache_parse) {
+        if (cd->cache_request || cd->cache_parse) {
                 p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR,
                                      cd->u.procfs.proc_ent,
                                      &cache_file_operations_procfs, cd);
@@ -1614,7 +1621,7 @@ static int create_cache_proc_entries(struct cache_detail *cd, struct net *net)
                         goto out_nomem;
         }
         if (cd->cache_show) {
-                p = proc_create_data("content", S_IFREG|S_IRUSR|S_IWUSR,
+                p = proc_create_data("content", S_IFREG|S_IRUSR,
                                 cd->u.procfs.proc_ent,
                                 &content_file_operations_procfs, cd);
                 cd->u.procfs.content_ent = p;