rbd: rearrange some code for consistency

This patch just trivially moves around some code for consistency.

In preparation for initializing osd request data fields in
ceph_osdc_build_request(), I wanted to verify that rbd did in fact
call that immediately before it called ceph_osdc_start_request().
It was true (although image requests are built in a group and then
started as a group).  But I made the changes here just to make
it more obvious, by making all of the calls follow a common
sequence:
	osd_req_op_<optype>_init();
	ceph_osd_data_<type>_init()
	osd_req_op_<optype>_<datafield>()
	rbd_osd_req_format()
	...
	ret = rbd_obj_request_submit()

I moved the initialization of the callback for image object requests
into rbd_img_request_fill_bio(), again, for consistency.  To avoid
a forward reference, I moved the definition of rbd_img_obj_callback()
up in the file.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

1 files changed, 62 insertions, 66 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 4cfe9f96589e..db29783436c8 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1519,6 +1519,57 @@ static void rbd_img_request_destroy(struct kref *kref)
         kfree(img_request);
 }
 
+static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
+{
+        struct rbd_img_request *img_request;
+        u32 which = obj_request->which;
+        bool more = true;
+
+        img_request = obj_request->img_request;
+
+        dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
+        rbd_assert(img_request != NULL);
+        rbd_assert(img_request->rq != NULL);
+        rbd_assert(img_request->obj_request_count > 0);
+        rbd_assert(which != BAD_WHICH);
+        rbd_assert(which < img_request->obj_request_count);
+        rbd_assert(which >= img_request->next_completion);
+
+        spin_lock_irq(&img_request->completion_lock);
+        if (which != img_request->next_completion)
+                goto out;
+
+        for_each_obj_request_from(img_request, obj_request) {
+                unsigned int xferred;
+                int result;
+
+                rbd_assert(more);
+                rbd_assert(which < img_request->obj_request_count);
+
+                if (!obj_request_done_test(obj_request))
+                        break;
+
+                rbd_assert(obj_request->xferred <= (u64) UINT_MAX);
+                xferred = (unsigned int) obj_request->xferred;
+                result = (int) obj_request->result;
+                if (result)
+                        rbd_warn(NULL, "obj_request %s result %d xferred %u\n",
+                                img_request->write_request ? "write" : "read",
+                                result, xferred);
+
+                more = blk_end_request(img_request->rq, result, xferred);
+                which++;
+        }
+
+        rbd_assert(more ^ (which == img_request->obj_request_count));
+        img_request->next_completion = which;
+out:
+        spin_unlock_irq(&img_request->completion_lock);
+
+        if (!more)
+                rbd_img_request_complete(img_request);
+}
+
 static int rbd_img_request_fill_bio(struct rbd_img_request *img_request,
                                         struct bio *bio_list)
 {
@@ -1572,6 +1623,7 @@ static int rbd_img_request_fill_bio(struct rbd_img_request *img_request,
                 if (!osd_req)
                         goto out_partial;
                 obj_request->osd_req = osd_req;
+                obj_request->callback = rbd_img_obj_callback;
 
                 osd_data = write_request ? &osd_req->r_data_out
                                          : &osd_req->r_data_in;
@@ -1582,8 +1634,6 @@ static int rbd_img_request_fill_bio(struct rbd_img_request *img_request,
                 osd_req_op_extent_osd_data(osd_req, 0, osd_data);
                 rbd_osd_req_format(obj_request, write_request);
 
-                /* status and version are initially zero-filled */
-
                 rbd_img_obj_request_add(img_request, obj_request);
 
                 image_offset += length;
@@ -1601,57 +1651,6 @@ out_unwind:
         return -ENOMEM;
 }
 
-static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
-{
-        struct rbd_img_request *img_request;
-        u32 which = obj_request->which;
-        bool more = true;
-
-        img_request = obj_request->img_request;
-
-        dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
-        rbd_assert(img_request != NULL);
-        rbd_assert(img_request->rq != NULL);
-        rbd_assert(img_request->obj_request_count > 0);
-        rbd_assert(which != BAD_WHICH);
-        rbd_assert(which < img_request->obj_request_count);
-        rbd_assert(which >= img_request->next_completion);
-
-        spin_lock_irq(&img_request->completion_lock);
-        if (which != img_request->next_completion)
-                goto out;
-
-        for_each_obj_request_from(img_request, obj_request) {
-                unsigned int xferred;
-                int result;
-
-                rbd_assert(more);
-                rbd_assert(which < img_request->obj_request_count);
-
-                if (!obj_request_done_test(obj_request))
-                        break;
-
-                rbd_assert(obj_request->xferred <= (u64) UINT_MAX);
-                xferred = (unsigned int) obj_request->xferred;
-                result = (int) obj_request->result;
-                if (result)
-                        rbd_warn(NULL, "obj_request %s result %d xferred %u\n",
-                                img_request->write_request ? "write" : "read",
-                                result, xferred);
-
-                more = blk_end_request(img_request->rq, result, xferred);
-                which++;
-        }
-
-        rbd_assert(more ^ (which == img_request->obj_request_count));
-        img_request->next_completion = which;
-out:
-        spin_unlock_irq(&img_request->completion_lock);
-
-        if (!more)
-                rbd_img_request_complete(img_request);
-}
-
 static int rbd_img_request_submit(struct rbd_img_request *img_request)
 {
         struct rbd_device *rbd_dev = img_request->rbd_dev;
@@ -1663,7 +1662,6 @@ static int rbd_img_request_submit(struct rbd_img_request *img_request)
         for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
                 int ret;
 
-                obj_request->callback = rbd_img_obj_callback;
                 ret = rbd_obj_request_submit(osdc, obj_request);
                 if (ret)
                         return ret;
@@ -1682,7 +1680,7 @@ static int rbd_obj_notify_ack(struct rbd_device *rbd_dev,
                                    u64 ver, u64 notify_id)
 {
         struct rbd_obj_request *obj_request;
-        struct ceph_osd_client *osdc;
+        struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
         int ret;
 
         obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
@@ -1694,13 +1692,12 @@ static int rbd_obj_notify_ack(struct rbd_device *rbd_dev,
         obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
         if (!obj_request->osd_req)
                 goto out;
+        obj_request->callback = rbd_obj_request_put;
 
         osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
                                         notify_id, ver, 0);
         rbd_osd_req_format(obj_request, false);
 
-        osdc = &rbd_dev->rbd_client->client->osdc;
-        obj_request->callback = rbd_obj_request_put;
         ret = rbd_obj_request_submit(osdc, obj_request);
 out:
         if (ret)
@@ -1760,16 +1757,17 @@ static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, int start)
         if (!obj_request->osd_req)
                 goto out_cancel;
 
-        osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
-                                rbd_dev->watch_event->cookie,