Struct cdev is always the member of the struct cdev_priv. When devfs

needed to promote cdev to cdev_priv, the si_priv pointer was followed.

Use member2struct() to calculate address of the wrapping cdev_priv.
Rename si_priv to __si_reserved.

Tested by:	pho
Reviewed by:	ed
MFC after:	2 weeks

3 files changed, 10 insertions, 9 deletions

diff --git a/sys/fs/devfs/devfs_devs.c b/sys/fs/devfs/devfs_devs.c
index 1d5e3c9..45f8d58 100644
--- a/sys/fs/devfs/devfs_devs.c
+++ b/sys/fs/devfs/devfs_devs.c
@@ -125,7 +125,6 @@ devfs_alloc(void)
 	cdp->cdp_maxdirent = 0;
 
 	cdev = &cdp->cdp_c;
-	cdev->si_priv = cdp;
 
 	cdev->si_name = cdev->__si_namebuf;
 	LIST_INIT(&cdev->si_children);
@@ -137,7 +136,7 @@ devfs_free(struct cdev *cdev)
 {
 	struct cdev_priv *cdp;
 
-	cdp = cdev->si_priv;
+	cdp = cdev2priv(cdev);
 	if (cdev->si_cred != NULL)
 		crfree(cdev->si_cred);
 	if (cdp->cdp_inode > 0)
@@ -510,7 +509,7 @@ devfs_create(struct cdev *dev)
 	struct cdev_priv *cdp;
 
 	mtx_assert(&devmtx, MA_OWNED);
-	cdp = dev->si_priv;
+	cdp = cdev2priv(dev);
 	cdp->cdp_flags |= CDP_ACTIVE;
 	cdp->cdp_inode = alloc_unrl(devfs_inos);
 	dev_refl(dev);
@@ -524,7 +523,7 @@ devfs_destroy(struct cdev *dev)
 	struct cdev_priv *cdp;
 
 	mtx_assert(&devmtx, MA_OWNED);
-	cdp = dev->si_priv;
+	cdp = cdev2priv(dev);
 	cdp->cdp_flags &= ~CDP_ACTIVE;
 	devfs_generation++;
 }
diff --git a/sys/fs/devfs/devfs_int.h b/sys/fs/devfs/devfs_int.h
index df0ad56..5a61dd4 100644
--- a/sys/fs/devfs/devfs_int.h
+++ b/sys/fs/devfs/devfs_int.h
@@ -68,6 +68,8 @@ struct cdev_priv {
 	LIST_HEAD(, cdev_privdata) cdp_fdpriv;
 };
 
+#define	cdev2priv(c)	member2struct(cdev_priv, cdp_c, c)
+
 struct cdev *devfs_alloc(void);
 void devfs_free(struct cdev *);
 void devfs_create(struct cdev *dev);
diff --git a/sys/fs/devfs/devfs_vnops.c b/sys/fs/devfs/devfs_vnops.c
index 649f492d..8130642 100644
--- a/sys/fs/devfs/devfs_vnops.c
+++ b/sys/fs/devfs/devfs_vnops.c
@@ -132,7 +132,7 @@ devfs_set_cdevpriv(void *priv, cdevpriv_dtr_t priv_dtr)
 	fp = curthread->td_fpop;
 	if (fp == NULL)
 		return (ENOENT);
-	cdp = ((struct cdev *)fp->f_data)->si_priv;
+	cdp = cdev2priv((struct cdev *)fp->f_data);
 	p = malloc(sizeof(struct cdev_privdata), M_CDEVPDATA, M_WAITOK);
 	p->cdpd_data = priv;
 	p->cdpd_dtr = priv_dtr;
@@ -541,7 +541,7 @@ devfs_getattr(struct vop_getattr_args *ap)
 		fix(dev->si_ctime);
 		vap->va_ctime = dev->si_ctime;
 
-		vap->va_rdev = dev->si_priv->cdp_inode;
+		vap->va_rdev = cdev2priv(dev)->cdp_inode;
 	}
 	vap->va_gen = 0;
 	vap->va_flags = 0;
@@ -742,7 +742,7 @@ devfs_lookupx(struct vop_lookup_args *ap, int *dm_unlock)
 		}
 
 		dev_lock();
-		dde = &cdev->si_priv->cdp_dirents[dmp->dm_idx];
+		dde = &cdev2priv(cdev)->cdp_dirents[dmp->dm_idx];
 		if (dde != NULL && *dde != NULL)
 			de = *dde;
 		dev_unlock();
@@ -1141,7 +1141,7 @@ devfs_revoke(struct vop_revoke_args *ap)
 	KASSERT((ap->a_flags & REVOKEALL) != 0, ("devfs_revoke !REVOKEALL"));
 
 	dev = vp->v_rdev;
-	cdp = dev->si_priv;
+	cdp = cdev2priv(dev);
  
 	dev_lock();
 	cdp->cdp_inuse++;
@@ -1419,7 +1419,7 @@ dev2udev(struct cdev *x)
 {
 	if (x == NULL)
 		return (NODEV);
-	return (x->si_priv->cdp_inode);
+	return (cdev2priv(x)->cdp_inode);
 }
 
 static struct fileops devfs_ops_f = {