From: Liam R. Howlett <Liam.Howlett@Oracle.com>
Date: Tue, 18 Dec 2018 18:44:20 +0000 (-0500)
Subject: Revert "maple_tree: Add parent slot to maple state."
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=refs%2Fheads%2Fmaple;p=users%2Fjedix%2Flinux-maple.git

Revert "maple_tree: Add parent slot to maple state."

A parent slot may be useful for the final slot in a node, but that work
has been put on hold for now.

This reverts commit 4c0d859ef03a19feab889b0cf6a9562a65d2818e.
---

diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h
index b2e5300356f6..7ba0432c8c40 100644
--- a/include/linux/maple_tree.h
+++ b/include/linux/maple_tree.h
@@ -128,7 +128,6 @@ struct maple_state {
 	unsigned long min;	/* The smallest index to be found in %node */
 	unsigned long max;	/* The largest index to be found in %node */
 	unsigned long slot_idx; /* The slot index from %node */
-	unsigned long pslot_idx; /* The slot index from the parent %node */
 	struct maple_node *alloc;	/* Allocated for this operation */
 	short flags;            /* Different stuff */
 };
diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 85470e348109..7b272ebdab59 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -206,7 +206,6 @@ static void *_maple_walk_4(struct maple_state *ms)
 {
 	struct maple_node_4 *mn4 = &ms->node->map4;
 
-	ms->pslot_idx = ms->slot_idx;
 	ms->slot_idx = ms->index - ms->min;
 	return rcu_dereference(mn4->slot[ms->slot_idx]);
 }
@@ -223,7 +222,6 @@ static void *_maple_walk_64(struct maple_state *ms, unsigned long val)
 			break;
 	} while (i++ < MAPLE_NODE64_MAX_SLOT - 1);
 
-	ms->pslot_idx = ms->slot_idx;
 	ms->slot_idx = i;
 	return rcu_dereference(mn64->slot[i]);
 }
@@ -391,7 +389,6 @@ static void _maple_root_expand(struct maple_state *ms)
 	if (r_entry != NULL) {
 		RCU_INIT_POINTER(mn->map64.slot[0], r_entry);
 		mn->map64.pivot[0] = 1;
-		ms->pslot_idx = 0;
 		ms->slot_idx = 1;
 	}
 
@@ -542,15 +539,18 @@ void maple_link_node(struct maple_state *ms,
 
 		left->parent = full->parent;
 		right->parent = full->parent;
+		/* Get the slot_idx to overwrite in the parent */
+		ms->node = full->parent;
+		_maple_walk_64(ms, ms->index);
 		/* Shift the data over */
-		maple_shift_64(target, ms->pslot_idx, 1);
+		maple_shift_64(target, ms->slot_idx, 1);
 		/* Overwrite the duplicate slot data with the new right node */
-		target->slot[ms->pslot_idx + 1] = ma_mk_node(right);
+		target->slot[ms->slot_idx + 1] = ma_mk_node(right);
 		/* Overwrite the first pivot with the new value.  This is fine
 		 * as the current slot has valid entries for this pivot */
-		target->pivot[ms->pslot_idx] = left64->pivot[l_end];
+		target->pivot[ms->slot_idx] = left64->pivot[l_end];
 		/* Set the first slot to the node with less pivots */
-		target->slot[ms->pslot_idx] = ma_mk_node(left);
+		target->slot[ms->slot_idx] = ma_mk_node(left);
 		/* Update the new nodes children's parent setting */
 		maple_update_parent(left);
 		maple_update_parent(right);