Remove all traces of Julians DEVFS (incl from kern/subr_diskslice.c)

  Remove old DEVFS support fields from dev_t.

  Make uid, gid & mode members of dev_t and set them in make_dev().

  Use correct uid, gid & mode in make_dev in disk minilayer.

  Add support for registering alias names for a dev_t using the
  new function make_dev_alias().  These will show up as symlinks
  in DEVFS.

  Use makedev() rather than make_dev() for MFSs magic devices to prevent
  DEVFS from noticing this abuse.

  Add a field for DEVFS inode number in dev_t.

  Add new DEVFS in fs/devfs.

  Add devfs cloning to:
        disk minilayer (ie: ad(4), sd(4), cd(4) etc etc)
        md(4), tun(4), bpf(4), fd(4)

  If DEVFS add -d flag to /sbin/inits args to make it mount devfs.

  Add commented out DEVFS to GENERIC

1 files changed, 54 insertions, 15 deletions

diff --git a/sys/kern/kern_conf.c b/sys/kern/kern_conf.c
index d6116f75513f..1e344e357450 100644
--- a/sys/kern/kern_conf.c
+++ b/sys/kern/kern_conf.c
@@ -195,13 +195,33 @@ makebdev(int x, int y)
 	return (makedev(bmaj2cmaj[x], y));
 }
 
+static dev_t
+allocdev(void)
+{
+	static int stashed;
+	struct specinfo *si;
+
+	if (stashed >= DEVT_STASH) {
+		MALLOC(si, struct specinfo *, sizeof(*si), M_DEVT,
+		    M_USE_RESERVE);
+		bzero(si, sizeof(*si));
+	} else if (LIST_FIRST(&dev_free)) {
+		si = LIST_FIRST(&dev_free);
+		LIST_REMOVE(si, si_hash);
+	} else {
+		si = devt_stash + stashed++;
+		si->si_flags |= SI_STASHED;
+	}
+	LIST_INIT(&si->si_names);
+	return (si);
+}
+
 dev_t
 makedev(int x, int y)
 {
 	struct specinfo *si;
 	udev_t	udev;
 	int hash;
-	static int stashed;
 
 	if (x == umajor(NOUDEV) && y == uminor(NOUDEV))
 		Debugger("makedev of NOUDEV");
@@ -211,17 +231,7 @@ makedev(int x, int y)
 		if (si->si_udev == udev)
 			return (si);
 	}
-	if (stashed >= DEVT_STASH) {
-		MALLOC(si, struct specinfo *, sizeof(*si), M_DEVT,
-		    M_USE_RESERVE);
-		bzero(si, sizeof(*si));
-	} else if (LIST_FIRST(&dev_free)) {
-		si = LIST_FIRST(&dev_free);
-		LIST_REMOVE(si, si_hash);
-	} else {
-		si = devt_stash + stashed++;
-		si->si_flags |= SI_STASHED;
-	}
+	si = allocdev();
 	si->si_udev = udev;
 	LIST_INSERT_HEAD(&dev_hash[hash], si, si_hash);
         return (si);
@@ -230,7 +240,7 @@ makedev(int x, int y)
 void
 freedev(dev_t dev)
 {
-	int hash;
+	dev_t adev;
 
 	if (!free_devt)
 		return;
@@ -238,7 +248,11 @@ freedev(dev_t dev)
 		return;
 	if (dev->si_devsw || dev->si_drv1 || dev->si_drv2)
 		return;
-	hash = dev->si_udev % DEVT_HASH;
+	while (!LIST_EMPTY(&dev->si_names)) {
+		adev = LIST_FIRST(&dev->si_names);
+		adev->si_drv1 = NULL;
+		freedev(adev);
+	}
 	LIST_REMOVE(dev, si_hash);
 	if (dev->si_flags & SI_STASHED) {
 		bzero(dev, sizeof(*dev));
@@ -304,9 +318,34 @@ make_dev(struct cdevsw *devsw, int minor, uid_t uid, gid_t gid, int perms, char
 	dev->si_name[i] = '\0';
 	va_end(ap);
 	dev->si_devsw = devsw;
+	dev->si_uid = uid;
+	dev->si_gid = gid;
+	dev->si_mode = perms;
+
+	if (devfs_create_hook)
+		devfs_create_hook(dev);
+	return (dev);
+}
+
+dev_t
+make_dev_alias(dev_t pdev, char *fmt, ...)
+{
+	dev_t	dev;
+	va_list ap;
+	int i;
+
+	dev = allocdev();
+	dev->si_flags |= SI_ALIAS;
+	dev->si_drv1 = pdev;
+	LIST_INSERT_HEAD(&pdev->si_names, dev, si_hash);
+
+	va_start(ap, fmt);
+	i = kvprintf(fmt, NULL, dev->si_name, 32, ap);
+	dev->si_name[i] = '\0';
+	va_end(ap);
 
 	if (devfs_create_hook)
-		devfs_create_hook(dev, uid, gid, perms);
+		devfs_create_hook(dev);
 	return (dev);
 }