From 5471a80a96a7ae7e4c34e44ddf9bb200cf1f9195 Mon Sep 17 00:00:00 2001
From: Alasdair Kergon <agk@redhat.com>
Date: Fri, 30 Sep 2005 22:20:14 +0000
Subject: [PATCH] Impose chunk size limitation.

---
 tools/lvcreate.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/lvcreate.c b/tools/lvcreate.c
index 9dde01331..09097a2f0 100644
--- a/tools/lvcreate.c
+++ b/tools/lvcreate.c
@@ -303,7 +303,12 @@ static int _read_params(struct lvcreate_params *lp, struct cmd_context *cmd,
 			return 0;
 		}
 		lp->chunk_size = 2 * arg_uint_value(cmd, chunksize_ARG, 8);
-// FIXME Restrict chunk_size to power of 2 in range PAGE_SIZE up to 512k (=1024)
+		if (lp->chunk_size < 8 || lp->chunk_size > 1024 ||
+		    (lp->chunk_size & (lp->chunk_size - 1))) {
+			log_error("Chunk size must be a power of 2 in the "
+				  "range 4K to 512K");
+			return 0;
+		}
 		log_verbose("Setting chunksize to %d sectors.", lp->chunk_size);
 
 		if (!(lp->segtype = get_segtype_from_string(cmd, "snapshot"))) {