From ef50a3e34f93a067ada541346be3175e924331a2 Mon Sep 17 00:00:00 2001
From: Lars Ellenberg <lars.ellenberg@linbit.com>
Date: Wed, 1 Sep 2010 14:39:30 +0200
Subject: [PATCH] drbd: implicitly create unconfigured devices on sync-after
dependencies
If pacemaker (for example) decided to initialize minor devices not in
the exact sync-after dependency order, the configuration partially
failed with an error "The sync-after minor number is invalid". (Bugz. #322)
We can avoid that by implicitly creating unconfigured minor devices,
if others depend on them.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
---
drivers/block/drbd/drbd_nl.c | 76 +++++++++++++++++++-----------------
1 file changed, 41 insertions(+), 35 deletions(-)
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index d066190f997a..e0061a906ba8 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -413,6 +413,39 @@ int drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role, int force)
return r;
}
+static struct drbd_conf *ensure_mdev(int minor, int create)
+{
+ struct drbd_conf *mdev;
+
+ if (minor >= minor_count)
+ return NULL;
+
+ mdev = minor_to_mdev(minor);
+
+ if (!mdev && create) {
+ struct gendisk *disk = NULL;
+ mdev = drbd_new_device(minor);
+
+ spin_lock_irq(&drbd_pp_lock);
+ if (minor_table[minor] == NULL) {
+ minor_table[minor] = mdev;
+ disk = mdev->vdisk;
+ mdev = NULL;
+ } /* else: we lost the race */
+ spin_unlock_irq(&drbd_pp_lock);
+
+ if (disk) /* we won the race above */
+ /* in case we ever add a drbd_delete_device(),
+ * don't forget the del_gendisk! */
+ add_disk(disk);
+ else /* we lost the race above */
+ drbd_free_mdev(mdev);
+
+ mdev = minor_to_mdev(minor);
+ }
+
+ return mdev;
+}
static int drbd_nl_primary(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
struct drbd_nl_cfg_reply *reply)
@@ -1713,6 +1746,12 @@ static int drbd_nl_syncer_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *n
}
#undef AL_MAX
+ /* to avoid spurious errors when configuring minors before configuring
+ * the minors they depend on: if necessary, first create the minor we
+ * depend on */
+ if (sc.after >= 0)
+ ensure_mdev(sc.after, 1);
+
/* 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. */
@@ -2080,40 +2119,6 @@ out:
return 0;
}
-static struct drbd_conf *ensure_mdev(struct drbd_nl_cfg_req *nlp)
-{
- struct drbd_conf *mdev;
-
- if (nlp->drbd_minor >= minor_count)
- return NULL;
-
- mdev = minor_to_mdev(nlp->drbd_minor);
-
- if (!mdev && (nlp->flags & DRBD_NL_CREATE_DEVICE)) {
- struct gendisk *disk = NULL;
- mdev = drbd_new_device(nlp->drbd_minor);
-
- spin_lock_irq(&drbd_pp_lock);
- if (minor_table[nlp->drbd_minor] == NULL) {
- minor_table[nlp->drbd_minor] = mdev;
- disk = mdev->vdisk;
- mdev = NULL;
- } /* else: we lost the race */
- spin_unlock_irq(&drbd_pp_lock);
-
- if (disk) /* we won the race above */
- /* in case we ever add a drbd_delete_device(),
- * don't forget the del_gendisk! */
- add_disk(disk);
- else /* we lost the race above */
- drbd_free_mdev(mdev);
-
- mdev = minor_to_mdev(nlp->drbd_minor);
- }
-
- return mdev;
-}
-
struct cn_handler_struct {
int (*function)(struct drbd_conf *,
struct drbd_nl_cfg_req *,
@@ -2174,7 +2179,8 @@ static void drbd_connector_callback(struct cn_msg *req, struct netlink_skb_parms
goto fail;
}
- mdev = ensure_mdev(nlp);
+ mdev = ensure_mdev(nlp->drbd_minor,
+ (nlp->flags & DRBD_NL_CREATE_DEVICE));
if (!mdev) {
retcode = ERR_MINOR_INVALID;
goto fail;
--
2.34.1