svn commit: r189112 - head/sbin/newfs_msdos

[Andriy Gapon]

Author: avg
Date: Fri Feb 27 17:29:48 2009
New Revision: 189112
URL: http://svn.freebsd.org/changeset/base/189112

Log:
  newfs_msdos: allow to work with media that doesn't have any CHS params
  
  Either use parameters provided by user or make them up.
  The code for faking CHS params is borrowed from disklabel code.
  The logic for using user-provided and auto-guessed parameters is not
  perfect, so to speak.
  
  PR:		bin/121182
  Approved by:	jhb (mentor)

Modified:
  head/sbin/newfs_msdos/newfs_msdos.c

Modified: head/sbin/newfs_msdos/newfs_msdos.c
==============================================================================
--- head/sbin/newfs_msdos/newfs_msdos.c	Fri Feb 27 17:29:31 2009	(r189111)
+++ head/sbin/newfs_msdos/newfs_msdos.c	Fri Feb 27 17:29:48 2009	(r189112)
@@ -793,13 +793,25 @@ getdiskinfo(int fd, const char *fname, c
     /* Maybe it's a fixed drive */
     if (lp == NULL) {
 	if (ioctl(fd, DIOCGDINFO, &dlp) == -1) {
-	    if (ioctl(fd, DIOCGSECTORSIZE, &dlp.d_secsize) == -1)
+	    if (bpb->bps == 0 && ioctl(fd, DIOCGSECTORSIZE, &dlp.d_secsize) == -1)
 		errx(1, "Cannot get sector size, %s", strerror(errno));
-	    if (ioctl(fd, DIOCGFWSECTORS, &dlp.d_nsectors) == -1)
-		errx(1, "Cannot get number of sectors, %s", strerror(errno));
-	    if (ioctl(fd, DIOCGFWHEADS, &dlp.d_ntracks)== -1)
-		errx(1, "Cannot get number of heads, %s", strerror(errno));
+
+	    /* XXX Should we use bpb->bps if it's set? */
 	    dlp.d_secperunit = ms / dlp.d_secsize;
+
+	    if (bpb->spt == 0 && ioctl(fd, DIOCGFWSECTORS, &dlp.d_nsectors) == -1) {
+		warnx("Cannot get number of sectors per track, %s", strerror(errno));
+		dlp.d_nsectors = 63;
+	    }
+	    if (bpb->hds == 0 && ioctl(fd, DIOCGFWHEADS, &dlp.d_ntracks) == -1) {
+		warnx("Cannot get number of heads, %s", strerror(errno));
+		if (dlp.d_secperunit <= 63*1*1024)
+		    dlp.d_ntracks = 1;
+		else if (dlp.d_secperunit <= 63*16*1024)
+		    dlp.d_ntracks = 16;
+		else
+		    dlp.d_ntracks = 255;
+	    }
 	}
 
 	hs = (ms / dlp.d_secsize) - dlp.d_secperunit;