dm io: prepare for new interface

[linux-2.6-block.git] / drivers / md / md.c

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 6c06e825cff5af8f070ff9d370f987da7c64f34b..2b4315d7e5d6531573e7ecfedd425df19178a3f3 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1318,6 +1318,7 @@ static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
        char b[BDEVNAME_SIZE];
        struct kobject *ko;
        char *s;
+       int err;
 
        if (rdev->mddev) {
                MD_BUG();
@@ -1352,20 +1353,35 @@ static int bind_rdev_to_array(mdk_rdev_t * rdev, mddev_t * mddev)
        while ( (s=strchr(rdev->kobj.k_name, '/')) != NULL)
                *s = '!';
                        
-       list_add(&rdev->same_set, &mddev->disks);
        rdev->mddev = mddev;
        printk(KERN_INFO "md: bind<%s>\n", b);
 
        rdev->kobj.parent = &mddev->kobj;
-       kobject_add(&rdev->kobj);
+       if ((err = kobject_add(&rdev->kobj)))
+               goto fail;
 
        if (rdev->bdev->bd_part)
                ko = &rdev->bdev->bd_part->kobj;
        else
                ko = &rdev->bdev->bd_disk->kobj;
-       sysfs_create_link(&rdev->kobj, ko, "block");
+       if ((err = sysfs_create_link(&rdev->kobj, ko, "block"))) {
+               kobject_del(&rdev->kobj);
+               goto fail;
+       }
+       list_add(&rdev->same_set, &mddev->disks);
        bd_claim_by_disk(rdev->bdev, rdev, mddev->gendisk);
        return 0;
+
+ fail:
+       printk(KERN_WARNING "md: failed to register dev-%s for %s\n",
+              b, mdname(mddev));
+       return err;
+}
+
+static void delayed_delete(struct work_struct *ws)
+{
+       mdk_rdev_t *rdev = container_of(ws, mdk_rdev_t, del_work);
+       kobject_del(&rdev->kobj);
 }
 
 static void unbind_rdev_from_array(mdk_rdev_t * rdev)
@@ -1380,7 +1396,12 @@ static void unbind_rdev_from_array(mdk_rdev_t * rdev)
        printk(KERN_INFO "md: unbind<%s>\n", bdevname(rdev->bdev,b));
        rdev->mddev = NULL;
        sysfs_remove_link(&rdev->kobj, "block");
-       kobject_del(&rdev->kobj);
+
+       /* We need to delay this, otherwise we can deadlock when
+        * writing to 'remove' to "dev/state"
+        */
+       INIT_WORK(&rdev->del_work, delayed_delete);
+       schedule_work(&rdev->del_work);
 }
 
 /*
@@ -2966,7 +2987,9 @@ static struct kobject *md_probe(dev_t dev, int *part, void *data)
        mddev->kobj.k_name = NULL;
        snprintf(mddev->kobj.name, KOBJ_NAME_LEN, "%s", "md");
        mddev->kobj.ktype = &md_ktype;
-       kobject_register(&mddev->kobj);
+       if (kobject_register(&mddev->kobj))
+               printk(KERN_WARNING "md: cannot register %s/md - name in use\n",
+                      disk->disk_name);
        return NULL;
 }
 
@@ -3057,7 +3080,7 @@ static int do_md_run(mddev_t * mddev)
                if (test_bit(Faulty, &rdev->flags))
                        continue;
                sync_blockdev(rdev->bdev);
-               invalidate_bdev(rdev->bdev, 0);
+               invalidate_bdev(rdev->bdev);
        }
 
        md_probe(mddev->unit, NULL, NULL);
@@ -3144,9 +3167,12 @@ static int do_md_run(mddev_t * mddev)
                bitmap_destroy(mddev);
                return err;
        }
-       if (mddev->pers->sync_request)
-               sysfs_create_group(&mddev->kobj, &md_redundancy_group);
-       else if (mddev->ro == 2) /* auto-readonly not meaningful */
+       if (mddev->pers->sync_request) {
+               if (sysfs_create_group(&mddev->kobj, &md_redundancy_group))
+                       printk(KERN_WARNING
+                              "md: cannot register extra attributes for %s\n",
+                              mdname(mddev));
+       } else if (mddev->ro == 2) /* auto-readonly not meaningful */
                mddev->ro = 0;
 
        atomic_set(&mddev->writes_pending,0);
@@ -3160,7 +3186,9 @@ static int do_md_run(mddev_t * mddev)
                if (rdev->raid_disk >= 0) {
                        char nm[20];
                        sprintf(nm, "rd%d", rdev->raid_disk);
-                       sysfs_create_link(&mddev->kobj, &rdev->kobj, nm);
+                       if (sysfs_create_link(&mddev->kobj, &rdev->kobj, nm))
+                               printk("md: cannot register %s for %s\n",
+                                      nm, mdname(mddev));
                }
        
        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
@@ -3325,6 +3353,7 @@ static int do_md_stop(mddev_t * mddev, int mode)
                        mddev->queue->merge_bvec_fn = NULL;
                        mddev->queue->unplug_fn = NULL;
                        mddev->queue->issue_flush_fn = NULL;
+                       mddev->queue->backing_dev_info.congested_fn = NULL;
                        if (mddev->pers->sync_request)
                                sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
 
@@ -3371,6 +3400,9 @@ static int do_md_stop(mddev_t * mddev, int mode)
                                sysfs_remove_link(&mddev->kobj, nm);
                        }
 
+               /* make sure all delayed_delete calls have finished */
+               flush_scheduled_work();
+
                export_array(mddev);
 
                mddev->array_size = 0;
@@ -5385,8 +5417,12 @@ static int remove_and_add_spares(mddev_t *mddev)
                                if (mddev->pers->hot_add_disk(mddev,rdev)) {
                                        char nm[20];
                                        sprintf(nm, "rd%d", rdev->raid_disk);
-                                       sysfs_create_link(&mddev->kobj,
-                                                         &rdev->kobj, nm);
+                                       if (sysfs_create_link(&mddev->kobj,
+                                                             &rdev->kobj, nm))
+                                               printk(KERN_WARNING
+                                                      "md: cannot register "
+                                                      "%s for %s\n",
+                                                      nm, mdname(mddev));
                                        spares++;
                                        md_new_event(mddev);
                                } else