kernel -- tmpfs: Convert tmpfs inode counter to per-mount field

tmpfs used a global counter under a spinlock to set inode numbers. This
should be a per-mount field, protected by the mount lock.

sys/vfs/tmpfs/tmpfs.h

@@ -398,6 +398,7 @@ struct tmpfs_mount {
 	struct objcache		*tm_dirent_pool;
 	struct objcache		*tm_node_pool;
 
+	int			tm_ino;
 	int			tm_flags;
 
 	struct netexport	tm_export;

sys/vfs/tmpfs/tmpfs_subr.c

@@ -54,9 +54,7 @@
 #include <vfs/tmpfs/tmpfs.h>
 #include <vfs/tmpfs/tmpfs_vnops.h>
 
-static ino_t t_ino = 2;
-static struct spinlock	ino_lock;
-static ino_t tmpfs_fetch_ino(void);
+static ino_t tmpfs_fetch_ino(struct tmpfs_mount *);
 
 /* --------------------------------------------------------------------- */
 
@@ -115,7 +113,7 @@ tmpfs_alloc_node(struct tmpfs_mount *tmp, enum vtype type,
 	nnode->tn_uid = uid;
 	nnode->tn_gid = gid;
 	nnode->tn_mode = mode;
-	nnode->tn_id = tmpfs_fetch_ino();
+	nnode->tn_id = tmpfs_fetch_ino(tmp);
 	nnode->tn_advlock.init_done = 0;
 
 	/* Type-specific initialization. */
@@ -1340,13 +1338,11 @@ tmpfs_truncate(struct vnode *vp, off_t length)
 /* --------------------------------------------------------------------- */
 
 static ino_t
-tmpfs_fetch_ino(void)
+tmpfs_fetch_ino(struct tmpfs_mount *tmp)
 {
-	ino_t	ret;
+	ino_t ret;
 
-	spin_lock(&ino_lock);
-	ret = t_ino++;
-	spin_unlock(&ino_lock);
+	ret = tmp->tm_ino++;
 
-	return ret;
+	return (ret);
 }

sys/vfs/tmpfs/tmpfs_vfsops.c

@@ -251,6 +251,8 @@ tmpfs_mount(struct mount *mp, char *path, caddr_t data, struct ucred *cred)
 	    tmpfs_node_init, tmpfs_node_fini,
 	    &tmp->tm_node_zone_malloc_args);
 
+	tmp->tm_ino = 2;
+
 	/* Allocate the root node. */
 	error = tmpfs_alloc_node(tmp, VDIR, root_uid, root_gid,
 				 root_mode & ALLPERMS, NULL, NULL,