[PATCH] xfs_growfs: don't grow data if only -m is specified

[Eric Sandeen]

While writing an xfstest to check imaxpct behavior, I realized
that xfs_growfs -m XXX /mnt/point will not only change
imaxpct, but also grow the filesystem if it's not currently
occupying the entire block device.  This doesn't seem like
the expected behavior, so split it out such that if only
-m, and not -d, is specified, only the imaxpct will be
changed.

This is a change from previous behavior, but I think it
satisfies the principle of least surprise...

Signed-off-by: Eric Sandeen <sandeen at redhat.com>
---

diff --git a/growfs/xfs_growfs.c b/growfs/xfs_growfs.c
index 2df68fb..fb7eda8 100644
--- a/growfs/xfs_growfs.c
+++ b/growfs/xfs_growfs.c
@@ -189,7 +189,7 @@ main(int argc, char **argv)
 		usage();
 	if (iflag && xflag)
 		usage();
-	if (dflag + lflag + rflag == 0)
+	if (dflag + lflag + rflag + mflag == 0)
 		aflag = 1;
 
 	fs_table_initialise(0, NULL, 0, NULL);
@@ -305,12 +305,15 @@ main(int argc, char **argv)
 	drsize -= (drsize % 2);
 
 	error = 0;
-	if (dflag | aflag) {
+
+	if (dflag | mflag | aflag) {
 		xfs_growfs_data_t	in;
 
 		if (!mflag)
 			maxpct = geo.imaxpct;
-		if (!dsize)
+		if (!dflag && !aflag)	/* Only mflag, no data size change */
+			dsize = geo.datablocks;
+		else if (!dsize)
 			dsize = ddsize / (geo.blocksize / BBSIZE);
 		else if (dsize > ddsize / (geo.blocksize / BBSIZE)) {
 			fprintf(stderr, _(