Merge branch 'stable/xen-pcifront-fixes' of git://git.kernel.org/pub/scm/linux/kernel...

[pandora-kernel.git] / drivers / block / drbd / drbd_nl.c

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 87925e9..29e5c70 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -870,6 +870,11 @@ static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp
                retcode = ERR_DISK_CONFIGURED;
                goto fail;
        }
+       /* It may just now have detached because of IO error.  Make sure
+        * drbd_ldev_destroy is done already, we may end up here very fast,
+        * e.g. if someone calls attach from the on-io-error handler,
+        * to realize a "hot spare" feature (not that I'd recommend that) */
+       wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
 
        /* allocation not in the IO path, cqueue thread context */
        nbc = kzalloc(sizeof(struct drbd_backing_dev), GFP_KERNEL);
@@ -1098,9 +1103,9 @@ static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp
        /* Reset the "barriers don't work" bits here, then force meta data to
         * be written, to ensure we determine if barriers are supported. */
        if (nbc->dc.no_md_flush)
-               set_bit(MD_NO_BARRIER, &mdev->flags);
+               set_bit(MD_NO_FUA, &mdev->flags);
        else
-               clear_bit(MD_NO_BARRIER, &mdev->flags);
+               clear_bit(MD_NO_FUA, &mdev->flags);
 
        /* Point of no return reached.
         * Devices and memory are no longer released by error cleanup below.
@@ -1112,8 +1117,8 @@ static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp
        nbc = NULL;
        resync_lru = NULL;
 
-       mdev->write_ordering = WO_bio_barrier;
-       drbd_bump_write_ordering(mdev, WO_bio_barrier);
+       mdev->write_ordering = WO_bdev_flush;
+       drbd_bump_write_ordering(mdev, WO_bdev_flush);
 
        if (drbd_md_test_flag(mdev->ldev, MDF_CRASHED_PRIMARY))
                set_bit(CRASHED_PRIMARY, &mdev->flags);
@@ -1262,7 +1267,7 @@ static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp
  force_diskless_dec:
        put_ldev(mdev);
  force_diskless:
-       drbd_force_state(mdev, NS(disk, D_DISKLESS));
+       drbd_force_state(mdev, NS(disk, D_FAILED));
        drbd_md_sync(mdev);
  release_bdev2_fail:
        if (nbc)
@@ -1285,10 +1290,19 @@ static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp
        return 0;
 }
 
+/* Detaching the disk is a process in multiple stages.  First we need to lock
+ * out application IO, in-flight IO, IO stuck in drbd_al_begin_io.
+ * Then we transition to D_DISKLESS, and wait for put_ldev() to return all
+ * internal references as well.
+ * Only then we have finally detached. */
 static int drbd_nl_detach(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
                          struct drbd_nl_cfg_reply *reply)
 {
+       drbd_suspend_io(mdev); /* so no-one is stuck in drbd_al_begin_io */
        reply->ret_code = drbd_request_state(mdev, NS(disk, D_DISKLESS));
+       if (mdev->state.disk == D_DISKLESS)
+               wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
+       drbd_resume_io(mdev);
        return 0;
 }
 
@@ -1953,7 +1967,6 @@ static int drbd_nl_resume_io(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp
        if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
                drbd_uuid_new_current(mdev);
                clear_bit(NEW_CUR_UUID, &mdev->flags);
-               drbd_md_sync(mdev);
        }
        drbd_suspend_io(mdev);
        reply->ret_code = drbd_request_state(mdev, NS3(susp, 0, susp_nod, 0, susp_fen, 0));