[PATCH 2/2 V2] mkfs.xfs: don't call blkid_get_topology on regular files

[Eric Sandeen]

If we encounter a target that's really a regular file,
even without "-d file..." on the cmdline, call
platform_findsizes() instead of blkid_get_topology to
try to discover the "sector size" via the fsgeom() call.

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

V2: Lose local "isa_file" flag, just switch based on 
(xi->disfile) or (stat works & S_ISREG)

diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index 188b6b3..3b8bf67 100644
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -456,9 +456,25 @@ static void get_topology(
 	struct fs_topology	*ft,
 	int			force_overwrite)
 {
-	if (!xi->disfile) {
-		const char *dfile = xi->volname ? xi->volname : xi->dname;
+	struct stat statbuf;
+	char *dfile = xi->volname ? xi->volname : xi->dname;
 
+	/*
+	 * Don't call blkid for topology if this is a "-d file" target, or
+	 * if we've simply been pointed at a regular file.  platform_findsizes
+	 * will attempt to find the underlying sector size of the host fs.
+	 */
+	if (xi->disfile ||
+	    (!stat(dfile, &statbuf) && S_ISREG(statbuf.st_mode))) {
+		int fd;
+		long long dummy;
+
+		fd = open(dfile, O_RDONLY);
+		if (fd >= 0) {
+			platform_findsizes(dfile, fd, &dummy, &ft->lsectorsize);
+			close(fd);
+		}
+	} else {
 		blkid_get_topology(dfile, &ft->dsunit, &ft->dswidth,
 				   &ft->lsectorsize, &ft->psectorsize,
 				   force_overwrite);