Add initialising_pg flag and remap ios when processing queue.
--- diff/drivers/md/dm-mpath.c	2004-10-29 15:38:23.000000000 +0100
+++ source/drivers/md/dm-mpath.c	2004-10-29 15:38:29.000000000 +0100
@@ -53,6 +53,7 @@
 
 	unsigned nr_priority_groups;
 	struct list_head priority_groups;
+	int initialising_pg;
 
 	spinlock_t lock;
 	unsigned nr_valid_paths;
@@ -208,40 +209,52 @@
 	return 0;
 }
 
-static struct path *__get_current_path(struct multipath *m)
+static int map_io(struct multipath *m, struct bio *bio, struct mpath_io *mpio)
 {
-	struct path *path;
+	unsigned long flags;
+	struct path *path = NULL;
+	int must_queue = 0;
+
+	spin_lock_irqsave(&m->lock, flags);
 
 	/* Do we need to select a new path? */
-	if (!m->current_path || (m->current_count && --m->current_count == 0))
+	if (!m->initialising_pg &&
+	    (!m->current_path || (m->current_count && --m->current_count == 0)))
 		__choose_path(m);
 
-	path = m->current_path;
+	if (m->initialising_pg)
+		must_queue = 1;
+	else if (m->current_path)
+		path = m->current_path;
 
-	return path;
-}
-
-static int map_io(struct multipath *m, struct bio *bio, struct mpath_io *mpio)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&m->lock, flags);
-	mpio->path = __get_current_path(m);
 	spin_unlock_irqrestore(&m->lock, flags);
 
-	if (!mpio->path)
+	if (!must_queue && !path)
 		return -EIO;
 
+	mpio->path = path;
 	bio->bi_bdev = mpio->path->dev->bdev;
-	return 1;
+
+	if (!must_queue)
+		return 1;	/* Mapped successfully */
+
+	/* queue for the daemon to resubmit */
+	spin_lock_irqsave(&m->lock, flags);
+	bio_list_add(&m->queued_ios, bio);
+	spin_unlock_irqrestore(&m->lock, flags);
+
+	return 0;		/* Queued */
 }
 
 static void dispatch_queued_ios(void *data)
 {
 	struct multipath *m = (struct multipath *) data;
 
+	int r;
 	unsigned long flags;
 	struct bio *bio = NULL, *next;
+	struct mpath_io *mpio;
+	union map_info *info;
 
 	spin_lock_irqsave(&m->lock, flags);
 	bio = bio_list_get(&m->queued_ios);
@@ -250,7 +263,16 @@
 	while (bio) {
 		next = bio->bi_next;
 		bio->bi_next = NULL;
-		generic_make_request(bio);
+
+		info = dm_get_mapinfo(bio);
+		mpio = info->ptr;
+
+		r = map_io(m, bio, mpio);
+		if (r < 0)
+			bio_endio(bio, bio->bi_size, r);
+		else if (r == 1)
+			generic_make_request(bio);
+
 		bio = next;
 	}
 }
@@ -536,12 +558,11 @@
 	mpio = mempool_alloc(m->mpio_pool, GFP_NOIO);
 	dm_bio_record(&mpio->details, bio);
 
+	map_context->ptr = mpio;
 	bio->bi_rw |= (1 << BIO_RW_FAILFAST);
 	r = map_io(m, bio, mpio);
 	if (r < 0)
 		mempool_free(mpio, m->mpio_pool);
-	else
-		map_context->ptr = mpio;
 
 	return r;
 }
@@ -673,7 +694,6 @@
 static int do_end_io(struct multipath *m, struct bio *bio,
 		     int error, struct mpath_io *mpio)
 {
-	int r;
 	struct hw_handler *hwh = &m->hw_handler;
 	unsigned err_flags = MP_FAIL_PATH;	/* Default behavior */
 
@@ -697,19 +717,15 @@
 		if (!(err_flags & MP_RETRY_IO))
 			return -EIO;
 
-		/* remap */
 		dm_bio_restore(&mpio->details, bio);
-		r = map_io(m, bio, mpio);
-		if (r < 0)
-			/* no paths left */
-			return r;
 
-		/* queue for the daemon to resubmit */
+		/* queue for the daemon to resubmit or fail */
 		spin_lock(&m->lock);
 		bio_list_add(&m->queued_ios, bio);
+		if (!m->initialising_pg)
+			schedule_work(&m->dispatch_queued);
 		spin_unlock(&m->lock);
 
-		schedule_work(&m->dispatch_queued);
 		return 1;	/* io not complete */
 	}
 
--- diff/drivers/md/dm.c	2004-10-29 15:37:22.000000000 +0100
+++ source/drivers/md/dm.c	2004-10-29 15:38:29.000000000 +0100
@@ -43,6 +43,13 @@
 	union map_info info;
 };
 
+union map_info *dm_get_mapinfo(struct bio *bio)
+{
+        if (bio && bio->bi_private)
+                return &((struct target_io *)bio->bi_private)->info;
+        return NULL;
+}
+
 /*
  * Bits for the md->flags field.
  */
@@ -1162,6 +1169,8 @@
 	.owner = THIS_MODULE
 };
 
+EXPORT_SYMBOL(dm_get_mapinfo);
+
 /*
  * module hooks
  */
--- diff/drivers/md/dm.h	2004-10-29 15:37:22.000000000 +0100
+++ source/drivers/md/dm.h	2004-10-29 15:38:29.000000000 +0100
@@ -187,5 +187,6 @@
 void dm_stripe_exit(void);
 
 void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
+union map_info *dm_get_mapinfo(struct bio *bio);
 
 #endif