End the VOP experiment. Instead of the ridicolusly complicated operation

vector setup that has questionable features (that have, as far as I can
tell never been used in practice, atleast not in OpenBSD), remove all
the gunk and favor a simple struct full of function pointers that get
set directly by each of the filesystems.

Removes gobs of ugly code and makes things simpler by a magnitude.

The only downside of this is that we loose the vnoperate feature so
the spec/fifo operations of the filesystems need to be kept in sync
with specfs and fifofs, this is no big deal as the API it self is pretty
static.

Many thanks to armani@ who pulled an earlier version of this diff to
current after c2k10 and Gabriel Kihlman on tech@ for testing.

Liked by many. "come on, find your balls" deraadt@.

1 files changed, 5 insertions, 153 deletions

diff --git a/sys/kern/vfs_init.c b/sys/kern/vfs_init.c
index 523aa8d4a55..34680ef087a 100644
--- a/sys/kern/vfs_init.c
+++ b/sys/kern/vfs_init.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vfs_init.c,v 1.25 2010/01/14 23:12:11 schwarze Exp $	*/
+/*	$OpenBSD: vfs_init.c,v 1.26 2010/09/06 23:44:10 thib Exp $	*/
 /*	$NetBSD: vfs_init.c,v 1.6 1996/02/09 19:00:58 christos Exp $	*/
 
 /*
@@ -50,150 +50,9 @@
 #include <sys/pool.h>
 #include <sys/systm.h>
 
-/* a list of lists of vnodeops defns */
-extern struct vnodeopv_desc *vfs_opv_descs[];
-
-/* and the operations they perform */
-extern struct vnodeop_desc *vfs_op_descs[];
-
 struct pool namei_pool;
 
-/*
- * This code doesn't work if the defn is **vnodop_defns with cc.
- * The problem is because of the compiler sometimes putting in an
- * extra level of indirection for arrays.  It's an interesting
- * "feature" of C.
- */
-int vfs_opv_numops;
-
-typedef int (*PFI)(void *);
-
-/*
- * vfs_init.c
- *
- * Allocate and fill in operations vectors.
- *
- * An undocumented feature of this approach to defining operations is that
- * there can be multiple entries in vfs_opv_descs for the same operations
- * vector. This allows third parties to extend the set of operations
- * supported by another layer in a binary compatible way. For example,
- * assume that NFS needed to be modified to support Ficus. NFS has an entry
- * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by
- * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions)
- * listing those new operations Ficus adds to NFS, all without modifying the
- * NFS code. (Of course, the OTW NFS protocol still needs to be munged, but
- * that is a(whole)nother story.) This is a feature.
- */
-
-/*
- * Allocate and init the vector, if it needs it.
- * Also handle backwards compatibility.
- */
-void
-vfs_opv_init_explicit(struct vnodeopv_desc *vfs_opv_desc)
-{
-	int (**opv_desc_vector)(void *);
-	struct vnodeopv_entry_desc *opve_descp;
-
-	opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p);
-
-	if (opv_desc_vector == NULL) {
-		/* XXX - shouldn't be M_VNODE */
-		opv_desc_vector = malloc(vfs_opv_numops * sizeof(PFI),
-		    M_VNODE, M_WAITOK|M_ZERO);
-		*(vfs_opv_desc->opv_desc_vector_p) = opv_desc_vector;
-	}
-
-	for (opve_descp = vfs_opv_desc->opv_desc_ops;
-	    opve_descp->opve_op; opve_descp++) {
-		/*
-		 * Sanity check:  is this operation listed
-		 * in the list of operations?  We check this
-		 * by seeing if its offset is zero.  Since
-		 * the default routine should always be listed
-		 * first, it should be the only one with a zero
-		 * offset.  Any other operation with a zero
-		 * offset is probably not listed in
-		 * vfs_op_descs, and so is probably an error.
-		 *
-		 * A panic here means the layer programmer
-		 * has committed the all-too common bug
-		 * of adding a new operation to the layer's
-		 * list of vnode operations but
-		 * not adding the operation to the system-wide
-		 * list of supported operations.
-		 */
-		if (opve_descp->opve_op->vdesc_offset == 0 &&
-		    opve_descp->opve_op != VDESC(vop_default)) {                
-			printf("operation %s not listed in %s.\n",
-			    opve_descp->opve_op->vdesc_name, "vfs_op_descs");
-			panic ("vfs_opv_init: bad operation");
-		}
-
-		/*
-		 * Fill in this entry.
-		 */
-		opv_desc_vector[opve_descp->opve_op->vdesc_offset] =
-		    opve_descp->opve_impl;
-	}
-}
-
-void
-vfs_opv_init_default(struct vnodeopv_desc *vfs_opv_desc)
-{
-	int j;
-	int (**opv_desc_vector)(void *);
-
-	opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p);
-
-	/*
-	 * Force every operations vector to have a default routine.
-	 */
-	if (opv_desc_vector[VOFFSET(vop_default)] == NULL)
-		panic("vfs_opv_init: operation vector without default routine.");
-
-	for (j = 0; j < vfs_opv_numops; j++)
-		if (opv_desc_vector[j] == NULL)
-			opv_desc_vector[j] =
-			    opv_desc_vector[VOFFSET(vop_default)];
-}
-
-/* Initialize known vnode operations vectors. */
-void
-vfs_op_init(void)
-{
-	int i;
-
-	/* Set all vnode vectors to a well known value. */
-	for (i = 0; vfs_opv_descs[i]; i++)
-		*(vfs_opv_descs[i]->opv_desc_vector_p) = NULL;
-
-	/*
-	 * Figure out how many ops there are by counting the table,
-	 * and assign each its offset.
-	 */
-	for (vfs_opv_numops = 0, i = 0; vfs_op_descs[i]; i++) {
-		vfs_op_descs[i]->vdesc_offset = vfs_opv_numops;
-		vfs_opv_numops++;
-	}
-
-	/* Allocate the dynamic vectors and fill them in. */
-	for (i = 0; vfs_opv_descs[i]; i++)
-		vfs_opv_init_explicit(vfs_opv_descs[i]);
-
-	/*
-	 * Finally, go back and replace unfilled routines
-	 * with their default.
-	 */
-	for (i = 0; vfs_opv_descs[i]; i++)
-		vfs_opv_init_default(vfs_opv_descs[i]);
-
-}
-
-
-/*
- * Initialize the vnode structures and initialize each file system type.
- */
+/* Initialize the vnode structures and initialize each file system type. */
 void
 vfsinit(void)
 {
@@ -204,18 +63,11 @@ vfsinit(void)
 	pool_init(&namei_pool, MAXPATHLEN, 0, 0, 0, "namei",
 	    &pool_allocator_nointr);
 
-	/*
-	 * Initialize the vnode table
-	 */
+	/* Initialize the vnode table. */
 	vntblinit();
-	/*
-	 * Initialize the vnode name cache
-	 */
+
+	/* Initialize the vnode name cache. */
 	nchinit();
-	/*
-	 * Build vnode operation vectors.
-	 */
-	vfs_op_init();
 
 	/*
 	 * Stop using vfsconf and maxvfsconf as a temporary storage,