ceph: simplify page setup for incoming data

Drop largely useless helper __prepare_pages(), and simplify sanity checks.

Signed-off-by: Sage Weil <sage@newdream.net>

diff --git a/fs/ceph/osd_client.c b/fs/ceph/osd_client.c
index 3514f71..22a33f8 100644 (file)
--- a/fs/ceph/osd_client.c
+++ b/fs/ceph/osd_client.c
@@ -1087,45 +1087,6 @@ bad:
        return;
 }
 
-
-/*
- * A read request prepares specific pages that data is to be read into.
- * When a message is being read off the wire, we call prepare_pages to
- * find those pages.
- *  0 = success, -1 failure.
- */
-static int __prepare_pages(struct ceph_connection *con,
-                        struct ceph_msg_header *hdr,
-                        struct ceph_osd_request *req,
-                        u64 tid,
-                        struct ceph_msg *m)
-{
-       struct ceph_osd *osd = con->private;
-       struct ceph_osd_client *osdc;
-       int ret = -1;
-       int data_len = le32_to_cpu(hdr->data_len);
-       unsigned data_off = le16_to_cpu(hdr->data_off);
-
-       int want = calc_pages_for(data_off & ~PAGE_MASK, data_len);
-
-       if (!osd)
-               return -1;
-
-       osdc = osd->o_osdc;
-
-       dout("__prepare_pages on msg %p tid %llu, has %d pages, want %d\n", m,
-            tid, req->r_num_pages, want);
-       if (unlikely(req->r_num_pages < want))
-               goto out;
-       m->pages = req->r_pages;
-       m->nr_pages = req->r_num_pages;
-       ret = 0; /* success */
-out:
-       BUG_ON(ret < 0 || m->nr_pages < want);
-
-       return ret;
-}
-
 /*
  * Register request, send initial attempt.
  */
@@ -1394,7 +1355,8 @@ static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
 }
 
 /*
- * lookup and return message for incoming reply
+ * lookup and return message for incoming reply.  set up reply message
+ * pages.
  */
 static struct ceph_msg *get_reply(struct ceph_connection *con,
                                  struct ceph_msg_header *hdr,
@@ -1407,7 +1369,6 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
        int front = le32_to_cpu(hdr->front_len);
        int data_len = le32_to_cpu(hdr->data_len);
        u64 tid;
-       int err;
 
        tid = le64_to_cpu(hdr->tid);
        mutex_lock(&osdc->request_mutex);
@@ -1439,12 +1400,19 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
        m = ceph_msg_get(req->r_reply);
 
        if (data_len > 0) {
-               err = __prepare_pages(con, hdr, req, tid, m);
-               if (err < 0) {
+               unsigned data_off = le16_to_cpu(hdr->data_off);
+               int want = calc_pages_for(data_off & ~PAGE_MASK, data_len);
+
+               if (unlikely(req->r_num_pages < want)) {
+                       pr_warning("tid %lld reply %d > expected %d pages\n",
+                                  tid, want, m->nr_pages);
                        *skip = 1;
                        ceph_msg_put(m);
-                       m = ERR_PTR(err);
+                       m = ERR_PTR(-EIO);
+                       goto out;
                }
+               m->pages = req->r_pages;
+               m->nr_pages = req->r_num_pages;
        }
        *skip = 0;
        req->r_con_filling_msg = ceph_con_get(con);