1 files changed, 133 insertions, 0 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index bce1fcfb5185..842caf4aab47 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -70,7 +70,10 @@
 
 #define RBD_SNAP_HEAD_NAME      "-"
 
+/* This allows a single page to hold an image name sent by OSD */
+#define RBD_IMAGE_NAME_LEN_MAX  (PAGE_SIZE - sizeof (__le32) - 1)
 #define RBD_IMAGE_ID_LEN_MAX    64
+
 #define RBD_OBJ_PREFIX_LEN_MAX  64
 
 /* Feature bits */
@@ -658,6 +661,20 @@ out_err:
         return -ENOMEM;
 }
 
+static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
+{
+        struct rbd_snap *snap;
+
+        if (snap_id == CEPH_NOSNAP)
+                return RBD_SNAP_HEAD_NAME;
+
+        list_for_each_entry(snap, &rbd_dev->snaps, node)
+                if (snap_id == snap->id)
+                        return snap->name;
+
+        return NULL;
+}
+
 static int snap_by_name(struct rbd_device *rbd_dev, const char *snap_name)
 {
 
@@ -2499,6 +2516,7 @@ static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
                 goto out_err;
         }
         parent_spec->image_id = image_id;
+        parent_spec->image_id_len = len;
         ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err);
         ceph_decode_64_safe(&p, end, overlap, out_err);
 
@@ -2514,6 +2532,117 @@ out_err:
         return ret;
 }
 
+static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
+{
+        size_t image_id_size;
+        char *image_id;
+        void *p;
+        void *end;
+        size_t size;
+        void *reply_buf = NULL;
+        size_t len = 0;
+        char *image_name = NULL;
+        int ret;
+
+        rbd_assert(!rbd_dev->spec->image_name);
+
+        image_id_size = sizeof (__le32) + rbd_dev->spec->image_id_len;
+        image_id = kmalloc(image_id_size, GFP_KERNEL);
+        if (!image_id)
+                return NULL;
+
+        p = image_id;
+        end = (char *) image_id + image_id_size;
+        ceph_encode_string(&p, end, rbd_dev->spec->image_id,
+                                (u32) rbd_dev->spec->image_id_len);
+
+        size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
+        reply_buf = kmalloc(size, GFP_KERNEL);
+        if (!reply_buf)
+                goto out;
+
+        ret = rbd_req_sync_exec(rbd_dev, RBD_DIRECTORY,
+                                "rbd", "dir_get_name",
+                                image_id, image_id_size,
+                                (char *) reply_buf, size,
+                                CEPH_OSD_FLAG_READ, NULL);
+        if (ret < 0)
+                goto out;
+        p = reply_buf;
+        end = (char *) reply_buf + size;
+        image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
+        if (IS_ERR(image_name))
+                image_name = NULL;
+        else
+                dout("%s: name is %s len is %zd\n", __func__, image_name, len);
+out:
+        kfree(reply_buf);
+        kfree(image_id);
+
+        return image_name;
+}
+
+/*
+ * When a parent image gets probed, we only have the pool, image,
+ * and snapshot ids but not the names of any of them.  This call
+ * is made later to fill in those names.  It has to be done after
+ * rbd_dev_snaps_update() has completed because some of the
+ * information (in particular, snapshot name) is not available
+ * until then.
+ */
+static int rbd_dev_probe_update_spec(struct rbd_device *rbd_dev)
+{
+        struct ceph_osd_client *osdc;
+        const char *name;
+        void *reply_buf = NULL;
+        int ret;
+
+        if (rbd_dev->spec->pool_name)
+                return 0;       /* Already have the names */
+
+        /* Look up the pool name */
+
+        osdc = &rbd_dev->rbd_client->client->osdc;
+        name = ceph_pg_pool_name_by_id(osdc->osdmap, rbd_dev->spec->pool_id);
+        if (!name)
+                return -EIO;    /* pool id too large (>= 2^31) */
+
+        rbd_dev->spec->pool_name = kstrdup(name, GFP_KERNEL);
+        if (!rbd_dev->spec->pool_name)
+                return -ENOMEM;
+
+        /* Fetch the image name; tolerate failure here */
+
+        name = rbd_dev_image_name(rbd_dev);
+        if (name) {
+                rbd_dev->spec->image_name_len = strlen(name);
+                rbd_dev->spec->image_name = (char *) name;
+        } else {
+                pr_warning(RBD_DRV_NAME "%d "
+                        "unable to get image name for image id %s\n",
+                        rbd_dev->major, rbd_dev->spec->image_id);
+        }
+
+        /* Look up the snapshot name. */
+
+        name = rbd_snap_name(rbd_dev, rbd_dev->spec->snap_id);
+        if (!name) {
+                ret = -EIO;
+                goto out_err;
+        }
+        rbd_dev->spec->snap_name = kstrdup(name, GFP_KERNEL);
+        if(!rbd_dev->spec->snap_name)
+                goto out_err;
+
+        return 0;
+out_err:
+        kfree(reply_buf);
+        kfree(rbd_dev->spec->pool_name);
+        rbd_dev->spec->pool_name = NULL;
+
+        return ret;
+}
+
 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, u64 *ver)
 {
         size_t size;
@@ -3372,6 +3501,10 @@ static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
         if (ret)
                 return ret;
 
+        ret = rbd_dev_probe_update_spec(rbd_dev);
+        if (ret)
+                goto err_out_snaps;
+
         ret = rbd_dev_set_mapping(rbd_dev);
         if (ret)
                 goto err_out_snaps;