[PATCH v2] mkfs: test that -l su is a multiple of block size

[Jan Tulak]

lsunit was already tested, but lsu was not. So a thing like -l su=4097 was
possible. This commit adds a check to catch this, and moves the entire
lsu/lsunit block size testing to calc_stripe_factors(), where already is some
logic w.r.t. lsu/lsunit.

Signed-off-by: Jan Tulak <jtulak at redhat.com>
---
UPDATE:
Moving the checks to calc_stripe_factors().

An example of previously failing options:
 mkfs.xfs -f -dfile,name=fsfile,size=128m -l su=16385
---
 mkfs/xfs_mkfs.c | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index 6059d91..b8f6b89 100644
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -726,6 +726,9 @@ struct opt_params mopts = {
  */
 #define WHACK_SIZE (128 * 1024)
 
+/*
+ * Convert lsu to lsunit for 512 bytes blocks and check validity of the values.
+ */
 static void
 calc_stripe_factors(
 	int		dsu,
@@ -775,6 +778,20 @@ calc_stripe_factors(
 
 	if (lsu)
 		*lsunit = (int)BTOBBT(lsu);
+
+	/* verify if lsu/lsunit is a multiple block size */
+	if (lsu % blocksize != 0) {
+		fprintf(stderr,
+_("log stripe unit (%d) must be a multiple of the block size (%d)\n"),
+		lsu, blocksize);
+		exit(1);
+	}
+	if ((BBTOB(*lsunit) % blocksize != 0)) {
+		fprintf(stderr,
+_("log stripe unit (%d) must be a multiple of the block size (%d)\n"),
+		BBTOB(*lsunit), blocksize);
+		exit(1);
+	}
 }
 
 /*
@@ -2862,12 +2879,6 @@ an AG size that is one stripe unit smaller, for example %llu.\n"),
 	 */
 
 	if (lsunit) {
-		if ((BBTOB(lsunit) % blocksize != 0)) {
-			fprintf(stderr,
-	_("log stripe unit (%d) must be a multiple of the block size (%d)\n"),
-			BBTOB(lsunit), blocksize);
-			exit(1);
-		}
 		/* convert from 512 byte blocks to fs blocks */
 		lsunit = DTOBT(lsunit);
 	} else if (sb_feat.log_version == 2 && loginternal && dsunit) {
-- 
2.5.5