Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

[cascardo/linux.git] / drivers / md / dm-mpath.c

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index eff7bdd..5a67671 100644 (file)
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -159,12 +159,9 @@ static struct priority_group *alloc_priority_group(void)
 static void free_pgpaths(struct list_head *pgpaths, struct dm_target *ti)
 {
        struct pgpath *pgpath, *tmp;
-       struct multipath *m = ti->private;
 
        list_for_each_entry_safe(pgpath, tmp, pgpaths, list) {
                list_del(&pgpath->list);
-               if (m->hw_handler_name)
-                       scsi_dh_detach(bdev_get_queue(pgpath->path.dev->bdev));
                dm_put_device(ti, pgpath->path.dev);
                free_pgpath(pgpath);
        }
@@ -580,6 +577,7 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
                q = bdev_get_queue(p->path.dev->bdev);
 
        if (m->retain_attached_hw_handler) {
+retain:
                attached_handler_name = scsi_dh_attached_handler_name(q, GFP_KERNEL);
                if (attached_handler_name) {
                        /*
@@ -599,20 +597,14 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
        }
 
        if (m->hw_handler_name) {
-               /*
-                * Increments scsi_dh reference, even when using an
-                * already-attached handler.
-                */
                r = scsi_dh_attach(q, m->hw_handler_name);
                if (r == -EBUSY) {
-                       /*
-                        * Already attached to different hw_handler:
-                        * try to reattach with correct one.
-                        */
-                       scsi_dh_detach(q);
-                       r = scsi_dh_attach(q, m->hw_handler_name);
-               }
+                       char b[BDEVNAME_SIZE];
 
+                       printk(KERN_INFO "dm-mpath: retaining handler on device %s\n",
+                               bdevname(p->path.dev->bdev, b));
+                       goto retain;
+               }
                if (r < 0) {
                        ti->error = "error attaching hardware handler";
                        dm_put_device(ti, p->path.dev);
@@ -624,7 +616,6 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
                        if (r < 0) {
                                ti->error = "unable to set hardware "
                                                        "handler parameters";
-                               scsi_dh_detach(q);
                                dm_put_device(ti, p->path.dev);
                                goto bad;
                        }
@@ -734,12 +725,6 @@ static int parse_hw_handler(struct dm_arg_set *as, struct multipath *m)
                return 0;
 
        m->hw_handler_name = kstrdup(dm_shift_arg(as), GFP_KERNEL);
-       if (!try_then_request_module(scsi_dh_handler_exist(m->hw_handler_name),
-                                    "scsi_dh_%s", m->hw_handler_name)) {
-               ti->error = "unknown hardware handler type";
-               ret = -EINVAL;
-               goto fail;
-       }
 
        if (hw_argc > 1) {
                char *p;