Added posix code

conts/posix/fs0/include/vfs.h

@@ -0,0 +1,90 @@
+#ifndef __VFS_H__
+#define __VFS_H__
+
+#include <fs.h>
+#include <lib/malloc.h>
+#include <l4/lib/list.h>
+#include <memfs/memfs.h>
+#include <l4/macros.h>
+#include <stdio.h>
+#include <task.h>
+#include <path.h>
+
+extern struct link vnode_cache;
+extern struct link dentry_cache;
+
+/*
+ * This is a temporary origacement for page cache support provided by mm0.
+ * Normally mm0 tracks all vnode pages, but this is used to track pages in
+ * directory vnodes, which are normally never mapped by tasks.
+ */
+static inline void *vfs_alloc_dirpage(struct vnode *v)
+{
+	/*
+	 * Urgh, we allocate from the block cache of memfs to store generic vfs directory
+	 * pages. This is currently the quickest we can allocate page-aligned memory.
+	 */
+	return memfs_alloc_block(v->sb->fs_super);
+}
+
+static inline void vfs_free_dirpage(struct vnode *v, void *block)
+{
+	memfs_free_block(v->sb->fs_super, block);
+}
+
+static inline struct dentry *vfs_alloc_dentry(void)
+{
+	struct dentry *d = kzalloc(sizeof(struct dentry));
+
+	link_init(&d->child);
+	link_init(&d->children);
+	link_init(&d->vref);
+	link_init(&d->cache_list);
+
+	return d;
+}
+
+static inline void vfs_free_dentry(struct dentry *d)
+{
+	return kfree(d);
+}
+
+static inline struct vnode *vfs_alloc_vnode(void)
+{
+	struct vnode *v = kzalloc(sizeof(struct vnode));
+
+	link_init(&v->dentries);
+	link_init(&v->cache_list);
+
+	return v;
+}
+
+static inline void vfs_free_vnode(struct vnode *v)
+{
+	BUG(); /* Are the dentries freed ??? */
+	list_remove(&v->cache_list);
+	kfree(v);
+}
+
+static inline struct superblock *vfs_alloc_superblock(void)
+{
+	struct superblock *sb = kmalloc(sizeof(struct superblock));
+	link_init(&sb->list);
+
+	return sb;
+}
+
+struct vfs_mountpoint {
+	struct superblock *sb;	/* The superblock of mounted filesystem */
+	struct vnode *pivot;	/* The dentry upon which we mount */
+};
+
+extern struct vfs_mountpoint vfs_root;
+
+int vfs_mount_root(struct superblock *sb);
+struct vnode *generic_vnode_lookup(struct vnode *thisnode, struct pathdata *p,
+				   const char *component);
+struct vnode *vfs_lookup_bypath(struct pathdata *p);
+struct vnode *vfs_lookup_byvnum(struct superblock *sb, unsigned long vnum);
+
+#endif /* __VFS_H__ */