libceph: split osdmap allocation and decode steps

Split osdmap allocation and initialization into a separate function,
ceph_osdmap_decode().

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Alex Elder <elder@linaro.org>

3 files changed, 31 insertions, 17 deletions

diff --git a/include/linux/ceph/osdmap.h b/include/linux/ceph/osdmap.h
index 8c8b3cefc28b..46c3e304c3d8 100644
--- a/include/linux/ceph/osdmap.h
+++ b/include/linux/ceph/osdmap.h
@@ -156,7 +156,7 @@ static inline int ceph_decode_pgid(void **p, void *end, struct ceph_pg *pgid)
         return 0;
 }
 
-extern struct ceph_osdmap *osdmap_decode(void **p, void *end);
+extern struct ceph_osdmap *ceph_osdmap_decode(void **p, void *end);
 extern struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
                                             struct ceph_osdmap *map,
                                             struct ceph_messenger *msgr);
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 71830d79b0f4..6f64eec18851 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -2062,7 +2062,7 @@ void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
                         int skipped_map = 0;
 
                         dout("taking full map %u len %d\n", epoch, maplen);
-                        newmap = osdmap_decode(&p, p+maplen);
+                        newmap = ceph_osdmap_decode(&p, p+maplen);
                         if (IS_ERR(newmap)) {
                                 err = PTR_ERR(newmap);
                                 goto bad;
diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c
index 4dd000d128fd..a82df6ea0749 100644
--- a/net/ceph/osdmap.c
+++ b/net/ceph/osdmap.c
@@ -684,9 +684,8 @@ static int osdmap_set_max_osd(struct ceph_osdmap *map, int max)
 /*
  * decode a full map.
  */
-struct ceph_osdmap *osdmap_decode(void **p, void *end)
+static int osdmap_decode(void **p, void *end, struct ceph_osdmap *map)
 {
-        struct ceph_osdmap *map;
         u16 version;
         u32 len, max, i;
         int err = -EINVAL;
@@ -694,14 +693,7 @@ struct ceph_osdmap *osdmap_decode(void **p, void *end)
         void *start = *p;
         struct ceph_pg_pool_info *pi;
 
-        dout("osdmap_decode %p to %p len %d\n", *p, end, (int)(end - *p));
-
-        map = kzalloc(sizeof(*map), GFP_NOFS);
-        if (map == NULL)
-                return ERR_PTR(-ENOMEM);
-
-        map->pg_temp = RB_ROOT;
-        mutex_init(&map->crush_scratch_mutex);
+        dout("%s %p to %p len %d\n", __func__, *p, end, (int)(end - *p));
 
         ceph_decode_16_safe(p, end, version, bad);
         if (version > 6) {
@@ -751,7 +743,6 @@ struct ceph_osdmap *osdmap_decode(void **p, void *end)
         err = osdmap_set_max_osd(map, max);
         if (err < 0)
                 goto bad;
-        dout("osdmap_decode max_osd = %d\n", map->max_osd);
 
         /* osds */
         err = -EINVAL;
@@ -819,7 +810,7 @@ struct ceph_osdmap *osdmap_decode(void **p, void *end)
         *p = end;
 
         dout("full osdmap epoch %d max_osd %d\n", map->epoch, map->max_osd);
-        return map;
+        return 0;
 
 bad:
         pr_err("corrupt full osdmap (%d) epoch %d off %d (%p of %p-%p)\n",
@@ -827,8 +818,31 @@ bad:
         print_hex_dump(KERN_DEBUG, "osdmap: ",
                        DUMP_PREFIX_OFFSET, 16, 1,
                        start, end - start, true);
-        ceph_osdmap_destroy(map);
-        return ERR_PTR(err);
+        return err;
+}
+
+/*
+ * Allocate and decode a full map.
+ */
+struct ceph_osdmap *ceph_osdmap_decode(void **p, void *end)
+{
+        struct ceph_osdmap *map;
+        int ret;
+
+        map = kzalloc(sizeof(*map), GFP_NOFS);
+        if (!map)
+                return ERR_PTR(-ENOMEM);
+
+        map->pg_temp = RB_ROOT;
+        mutex_init(&map->crush_scratch_mutex);
+
+        ret = osdmap_decode(p, end, map);
+        if (ret) {
+                ceph_osdmap_destroy(map);
+                return ERR_PTR(ret);
+        }
+
+        return map;
 }
 
 /*
@@ -872,7 +886,7 @@ struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
         if (len > 0) {
                 dout("apply_incremental full map len %d, %p to %p\n",
                      len, *p, end);
-                return osdmap_decode(p, min(*p+len, end));
+                return ceph_osdmap_decode(p, min(*p+len, end));
         }
 
         /* new crush? */