svn commit: r273131 - in head/sys: fs/deadfs fs/devfs sys

[Konstantin Belousov]

Author: kib
Date: Wed Oct 15 13:16:51 2014
New Revision: 273131
URL: https://svnweb.freebsd.org/changeset/base/273131

Log:
  When vnode bypass cannot be performed on the cdev file descriptor for
  read/write/poll/ioctl, call standard vnode filedescriptor fop.  This
  restores the special handling for terminals by calling the deadfs VOP,
  instead of always returning ENXIO for destroyed devices or revoked
  terminals.
  
  Since destroyed (and not revoked) device would use devfs_specops VOP
  vector, make dead_read/write/poll non-static and fill VOP table with
  pointers to the functions, to instead of VOP_PANIC.
  
  Noted and reviewed by:	bde
  Sponsored by:	The FreeBSD Foundation
  MFC after:	1 week

Modified:
  head/sys/fs/deadfs/dead_vnops.c
  head/sys/fs/devfs/devfs_vnops.c
  head/sys/sys/vnode.h

Modified: head/sys/fs/deadfs/dead_vnops.c
==============================================================================
--- head/sys/fs/deadfs/dead_vnops.c	Wed Oct 15 13:08:53 2014	(r273130)
+++ head/sys/fs/deadfs/dead_vnops.c	Wed Oct 15 13:16:51 2014	(r273131)
@@ -43,9 +43,6 @@
  */
 static vop_lookup_t	dead_lookup;
 static vop_open_t	dead_open;
-static vop_poll_t	dead_poll;
-static vop_read_t	dead_read;
-static vop_write_t	dead_write;
 static vop_getwritemount_t dead_getwritemount;
 static vop_rename_t	dead_rename;
 
@@ -130,7 +127,7 @@ dead_open(ap)
  * Vnode op for read
  */
 /* ARGSUSED */
-static int
+int
 dead_read(ap)
 	struct vop_read_args /* {
 		struct vnode *a_vp;
@@ -151,7 +148,7 @@ dead_read(ap)
  * Vnode op for write
  */
 /* ARGSUSED */
-static int
+int
 dead_write(ap)
 	struct vop_write_args /* {
 		struct vnode *a_vp;
@@ -163,7 +160,7 @@ dead_write(ap)
 	return (EIO);
 }
 
-static int
+int
 dead_poll(ap)
 	struct vop_poll_args *ap;
 {

Modified: head/sys/fs/devfs/devfs_vnops.c
==============================================================================
--- head/sys/fs/devfs/devfs_vnops.c	Wed Oct 15 13:08:53 2014	(r273130)
+++ head/sys/fs/devfs/devfs_vnops.c	Wed Oct 15 13:16:51 2014	(r273131)
@@ -737,8 +737,10 @@ devfs_ioctl_f(struct file *fp, u_long co
 
 	fpop = td->td_fpop;
 	error = devfs_fp_check(fp, &dev, &dsw, &ref);
-	if (error)
+	if (error != 0) {
+		error = vnops.fo_ioctl(fp, com, data, cred, td);
 		return (error);
+	}
 
 	if (com == FIODTYPE) {
 		*(int *)data = dsw->d_flags & D_TYPEMASK;
@@ -1152,8 +1154,10 @@ devfs_poll_f(struct file *fp, int events
 
 	fpop = td->td_fpop;
 	error = devfs_fp_check(fp, &dev, &dsw, &ref);
-	if (error)
-		return (poll_no_poll(events));
+	if (error != 0) {
+		error = vnops.fo_poll(fp, events, cred, td);
+		return (error);
+	}
 	error = dsw->d_poll(dev, events, td);
 	td->td_fpop = fpop;
 	dev_relthread(dev, ref);
@@ -1185,8 +1189,10 @@ devfs_read_f(struct file *fp, struct uio
 		return (EINVAL);
 	fpop = td->td_fpop;
 	error = devfs_fp_check(fp, &dev, &dsw, &ref);
-	if (error)
+	if (error != 0) {
+		error = vnops.fo_read(fp, uio, cred, flags, td);
 		return (error);
+	}
 	resid = uio->uio_resid;
 	ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT);
 	if (ioflag & O_DIRECT)
@@ -1660,8 +1666,10 @@ devfs_write_f(struct file *fp, struct ui
 		return (EINVAL);
 	fpop = td->td_fpop;
 	error = devfs_fp_check(fp, &dev, &dsw, &ref);
-	if (error)
+	if (error != 0) {
+		error = vnops.fo_write(fp, uio, cred, flags, td);
 		return (error);
+	}
 	KASSERT(uio->uio_td == td, ("uio_td %p is not td %p", uio->uio_td, td));
 	ioflag = fp->f_flag & (O_NONBLOCK | O_DIRECT | O_FSYNC);
 	if (ioflag & O_DIRECT)
@@ -1744,8 +1752,9 @@ static struct vop_vector devfs_specops =
 	.vop_mknod =		VOP_PANIC,
 	.vop_open =		devfs_open,
 	.vop_pathconf =		devfs_pathconf,
+	.vop_poll =		dead_poll,
 	.vop_print =		devfs_print,
-	.vop_read =		VOP_PANIC,
+	.vop_read =		dead_read,
 	.vop_readdir =		VOP_PANIC,
 	.vop_readlink =		VOP_PANIC,
 	.vop_reallocblks =	VOP_PANIC,
@@ -1761,7 +1770,7 @@ static struct vop_vector devfs_specops =
 	.vop_strategy =		VOP_PANIC,
 	.vop_symlink =		VOP_PANIC,
 	.vop_vptocnp =		devfs_vptocnp,
-	.vop_write =		VOP_PANIC,
+	.vop_write =		dead_write,
 };
 
 /*

Modified: head/sys/sys/vnode.h
==============================================================================
--- head/sys/sys/vnode.h	Wed Oct 15 13:08:53 2014	(r273130)
+++ head/sys/sys/vnode.h	Wed Oct 15 13:16:51 2014	(r273131)
@@ -758,6 +758,9 @@ int	vop_enoent(struct vop_generic_args *
 int	vop_enotty(struct vop_generic_args *ap);
 int	vop_null(struct vop_generic_args *ap);
 int	vop_panic(struct vop_generic_args *ap);
+int	dead_poll(struct vop_poll_args *ap);
+int	dead_read(struct vop_read_args *ap);
+int	dead_write(struct vop_write_args *ap);
 
 /* These are called from within the actual VOPS. */
 void	vop_create_post(void *a, int rc);