From 24ab1dd9b77664d9e10a78f858c6365641c34148 Mon Sep 17 00:00:00 2001
From: "S.J.R. van Schaik" <stephan@whiteboxsystems.nl>
Date: Thu, 18 May 2017 15:01:39 +0200
Subject: [PATCH] ftl: trim last sector by writing an empty page descriptor

---
 source/ftl/ftl.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/source/ftl/ftl.c b/source/ftl/ftl.c
index 27e23e9..68fdca4 100644
--- a/source/ftl/ftl.c
+++ b/source/ftl/ftl.c
@@ -650,9 +650,11 @@ int ftl_trim(struct ftl_journal *j, uint32_t va)
 
 	if (i == 32) {
 		j->root = UINT32_MAX;
-		/* TODO: how do we clean the FTL? */
 
-		return 0;
+		memset(&page_desc, 0xff, sizeof page_desc);
+		page_desc.nused_pages = 0;
+
+		return ftl_write_upage(j, NULL, &page_desc);
 	}
 
 	if (read_page_desc(j, &alt_page_desc, alt_va) < 0)