svn commit: r235330 - head/sys/boot/common

[Andriy Gapon]

Author: avg
Date: Sat May 12 09:07:41 2012
New Revision: 235330
URL: http://svn.freebsd.org/changeset/base/235330

Log:
  zfs boot: try to set vfs.root.mountfrom from currdev as a fallback
  
  This way with the new zfsloader there is no need to explicitly set zfs
  root filesystem either via vfs.root.mountfrom or fstab.
  It should be automatically picked up from currdev which is by default
  is set from bootfs.
  
  Tested by:	Florian Wagner <florian at wagner-flo.net> (x86)
  MFC after:	1 month

Modified:
  head/sys/boot/common/boot.c

Modified: head/sys/boot/common/boot.c
==============================================================================
--- head/sys/boot/common/boot.c	Sat May 12 09:03:30 2012	(r235329)
+++ head/sys/boot/common/boot.c	Sat May 12 09:07:41 2012	(r235330)
@@ -311,12 +311,12 @@ getrootmount(char *rootdev)
     if (getenv("vfs.root.mountfrom") != NULL)
 	return(0);
 
+    error = 1;
     sprintf(lbuf, "%s/etc/fstab", rootdev);
     if ((fd = open(lbuf, O_RDONLY)) < 0)
-	return(1);
+	goto notfound;
 
     /* loop reading lines from /etc/fstab    What was that about sscanf again? */
-    error = 1;
     while (fgetstr(lbuf, sizeof(lbuf), fd) >= 0) {
 	if ((lbuf[0] == 0) || (lbuf[0] == '#'))
 	    continue;
@@ -377,6 +377,20 @@ getrootmount(char *rootdev)
 	break;
     }
     close(fd);
+
+notfound:
+    if (error) {
+	const char *currdev;
+
+	currdev = getenv("currdev");
+	if (currdev != NULL && strncmp("zfs:", currdev, 4) == 0) {
+	    cp = strdup(currdev);
+	    cp[strlen(cp) - 1] = '\0';
+	    setenv("vfs.root.mountfrom", cp, 0);
+	    error = 0;
+	}
+    }
+
     return(error);
 }