drbd: Split drbd_alter_sa() into drbd_sync_after_valid() and drbd_sync_after_changed()

Preparing RCU for disk_conf

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 8c7e340..f8d0ac3 100644 (file)
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -1409,7 +1409,8 @@ extern int drbd_khelper(struct drbd_conf *mdev, char *cmd);
 
 /* drbd_worker.c */
 extern int drbd_worker(struct drbd_thread *thi);
-extern int drbd_alter_sa(struct drbd_conf *mdev, int na);
+enum drbd_ret_code drbd_sync_after_valid(struct drbd_conf *mdev, int o_minor);
+void drbd_sync_after_changed(struct drbd_conf *mdev);
 extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side);
 extern void resume_next_sg(struct drbd_conf *mdev);
 extern void suspend_other_sg(struct drbd_conf *mdev);

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 761a6b9..a1854e3 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1145,13 +1145,6 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
        if (!expect(new_disk_conf->al_extents <= DRBD_AL_EXTENTS_MAX))
                new_disk_conf->al_extents = DRBD_AL_EXTENTS_MAX;
 
-       /* most sanity checks done, try to assign the new sync-after
-        * dependency.  need to hold the global lock in there,
-        * to avoid a race in the dependency loop check. */
-       retcode = drbd_alter_sa(mdev, new_disk_conf->resync_after);
-       if (retcode != NO_ERROR)
-               goto fail;
-
        fifo_size = (new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ;
        if (fifo_size != mdev->rs_plan_s.size && fifo_size > 0) {
                rs_plan_s   = kzalloc(sizeof(int) * fifo_size, GFP_KERNEL);
@@ -1185,7 +1178,13 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
         * To avoid someone looking at a half-updated struct, we probably
         * should have a rw-semaphor on net_conf and disk_conf.
         */
-       mdev->ldev->dc = *new_disk_conf;
+       write_lock_irq(&global_state_lock);
+       retcode = drbd_sync_after_valid(mdev, new_disk_conf->resync_after);
+       if (retcode == NO_ERROR) {
+               mdev->ldev->dc = *new_disk_conf;
+               drbd_sync_after_changed(mdev);
+       }
+       write_unlock_irq(&global_state_lock);
 
        drbd_md_sync(mdev);
 

diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 0da1547..5b645e1 100644 (file)
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -1401,7 +1401,8 @@ void suspend_other_sg(struct drbd_conf *mdev)
        write_unlock_irq(&global_state_lock);
 }
 
-static int sync_after_error(struct drbd_conf *mdev, int o_minor)
+/* caller must hold global_state_lock */
+enum drbd_ret_code drbd_sync_after_valid(struct drbd_conf *mdev, int o_minor)
 {
        struct drbd_conf *odev;
 
@@ -1425,22 +1426,15 @@ static int sync_after_error(struct drbd_conf *mdev, int o_minor)
        }
 }
 
-int drbd_alter_sa(struct drbd_conf *mdev, int na)
+/* caller must hold global_state_lock */
+void drbd_sync_after_changed(struct drbd_conf *mdev)
 {
        int changes;
-       int retcode;
 
-       write_lock_irq(&global_state_lock);
-       retcode = sync_after_error(mdev, na);
-       if (retcode == NO_ERROR) {
-               mdev->ldev->dc.resync_after = na;
-               do {
-                       changes  = _drbd_pause_after(mdev);
-                       changes |= _drbd_resume_next(mdev);
-               } while (changes);
-       }
-       write_unlock_irq(&global_state_lock);
-       return retcode;
+       do {
+               changes  = _drbd_pause_after(mdev);
+               changes |= _drbd_resume_next(mdev);
+       } while (changes);
 }
 
 void drbd_rs_controller_reset(struct drbd_conf *mdev)