diff --git a/sys/dev/fdc/fdc.c b/sys/dev/fdc/fdc.c
index 788a7808e14c..0d659ab465ca 100644
--- a/sys/dev/fdc/fdc.c
+++ b/sys/dev/fdc/fdc.c
@@ -165,6 +165,8 @@ struct fdc_data
 	void	(*fdctl_wr)(struct fdc_data *fdc, u_int8_t v);
 };
 
+#define BIO_FORMAT	BIO_CMD2
+
 typedef int	fdu_t;
 typedef int	fdcu_t;
 typedef int	fdsu_t;
diff --git a/sys/geom/geom_io.c b/sys/geom/geom_io.c
index c43e568c7df2..c0eded7e799f 100644
--- a/sys/geom/geom_io.c
+++ b/sys/geom/geom_io.c
@@ -249,7 +249,6 @@ g_io_request(struct bio *bp, struct g_consumer *cp)
 			break;
 		case BIO_SETATTR:
 		case BIO_DELETE:
-		case BIO_FORMAT:
 			if ((cp->acw == 0) || (cp->ace == 0))
 				error = EPERM;
 			break;
diff --git a/sys/isa/fd.c b/sys/isa/fd.c
index 788a7808e14c..0d659ab465ca 100644
--- a/sys/isa/fd.c
+++ b/sys/isa/fd.c
@@ -165,6 +165,8 @@ struct fdc_data
 	void	(*fdctl_wr)(struct fdc_data *fdc, u_int8_t v);
 };
 
+#define BIO_FORMAT	BIO_CMD2
+
 typedef int	fdu_t;
 typedef int	fdcu_t;
 typedef int	fdsu_t;
diff --git a/sys/pc98/cbus/fdc.c b/sys/pc98/cbus/fdc.c
index 5e2b78cbcfef..d52138de3336 100644
--- a/sys/pc98/cbus/fdc.c
+++ b/sys/pc98/cbus/fdc.c
@@ -251,6 +251,7 @@ FDC_ACCESSOR(fdunit,	FDUNIT,	int)
 #endif
 
 #define BIO_RDSECTID	BIO_CMD1
+#define BIO_FORMAT	BIO_CMD2
 
 /*
  * List of native drive densities.  Order must match enum fd_drivetype
diff --git a/sys/pc98/pc98/fd.c b/sys/pc98/pc98/fd.c
index 5e2b78cbcfef..d52138de3336 100644
--- a/sys/pc98/pc98/fd.c
+++ b/sys/pc98/pc98/fd.c
@@ -251,6 +251,7 @@ FDC_ACCESSOR(fdunit,	FDUNIT,	int)
 #endif
 
 #define BIO_RDSECTID	BIO_CMD1
+#define BIO_FORMAT	BIO_CMD2
 
 /*
  * List of native drive densities.  Order must match enum fd_drivetype
diff --git a/sys/sys/bio.h b/sys/sys/bio.h
index 670150713cd4..5d35eeef4a76 100644
--- a/sys/sys/bio.h
+++ b/sys/sys/bio.h
@@ -95,9 +95,8 @@ struct bio {
 #define BIO_READ	0x00000001
 #define BIO_WRITE	0x00000002
 #define BIO_DELETE	0x00000004
-#define BIO_FORMAT	0x00000008
-#define BIO_GETATTR	0x00000010
-#define BIO_SETATTR	0x00000020
+#define BIO_GETATTR	0x00000008
+#define BIO_SETATTR	0x00000010
 #define BIO_CMD1	0x40000000	/* Available for local hacks */
 #define BIO_CMD2	0x80000000	/* Available for local hacks */