/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1997-2013 Apple Computer, Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
-/* Copyright (c) 1997 Apple Computer, Inc. All Rights Reserved */
/*-
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
#include <sys/tty.h>
#include <sys/vnode_internal.h>
#include <sys/file_internal.h>
-#ifndef NeXT
-#include <sys/kernel.h>
-#ifdef DEVFS
-#include <sys/devfsext.h>
-#endif /*DEVFS*/
-
-static d_open_t cttyopen;
-static d_read_t cttyread;
-static d_write_t cttywrite;
-static d_ioctl_t cttyioctl;
-static d_select_t cttyselect;
-
-#endif /* !NeXT */
+#include <sys/kauth.h>
/* Forward declarations for cdevsw[] entry */
/* XXX we should consider making these static */
-int cttyopen(dev_t dev, int flag, int mode, struct proc *p);
+int cttyopen(dev_t dev, int flag, int mode, proc_t p);
int cttyread(dev_t dev, struct uio *uio, int flag);
int cttywrite(dev_t dev, struct uio *uio, int flag);
-int cttyioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p);
-int cttyselect(dev_t dev, int flag, void* wql, struct proc *p);
-
-#ifndef NeXT
-
-#define CDEV_MAJOR 1
-/* Don't make static, fdesc_vnops uses this. */
-struct cdevsw ctty_cdevsw =
- { cttyopen, nullclose, cttyread, cttywrite, /*1*/
- cttyioctl, nullstop, nullreset, nodevtotty,/* tty */
- cttyselect, nommap, NULL, "ctty", NULL, -1 };
-
-#endif /* !NeXT */
+int cttyioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, proc_t p);
+int cttyselect(dev_t dev, int flag, void* wql, proc_t p);
+static vnode_t cttyvp(proc_t p);
-#define cttyvp(p) ((p)->p_flag & P_CONTROLT ? (p)->p_session->s_ttyvp : NULL)
-
-/*ARGSUSED*/
int
-cttyopen(__unused dev_t dev, int flag, __unused int mode, struct proc *p)
+cttyopen(dev_t dev, int flag, __unused int mode, proc_t p)
{
- struct vnode *ttyvp = cttyvp(p);
+ vnode_t ttyvp = cttyvp(p);
struct vfs_context context;
- int error;
+ int error = 0;
+ int cttyflag, doclose = 0;
+ struct session *sessp;
if (ttyvp == NULL)
return (ENXIO);
- context.vc_proc = p;
+ context.vc_thread = current_thread();
context.vc_ucred = kauth_cred_proc_ref(p);
- error = VNOP_OPEN(ttyvp, flag, &context);
+
+ sessp = proc_session(p);
+ session_lock(sessp);
+ cttyflag = sessp->s_flags & S_CTTYREF;
+ session_unlock(sessp);
+
+ /*
+ * A little hack--this device, used by many processes,
+ * happens to do an open on another device, which can
+ * cause unhappiness if the second-level open blocks indefinitely
+ * (as could be the case if the master side has hung up). Since
+ * we know that this driver doesn't care about the serializing
+ * opens and closes, we can drop the lock. To avoid opencount leak,
+ * open the vnode only for the first time.
+ */
+ if (cttyflag == 0) {
+ devsw_unlock(dev, S_IFCHR);
+ error = VNOP_OPEN(ttyvp, flag, &context);
+ devsw_lock(dev, S_IFCHR);
+
+ if (error)
+ goto out;
+
+ /*
+ * If S_CTTYREF is set, some other thread did an open
+ * and was able to set the flag, now perform a close, else
+ * set the flag.
+ */
+ session_lock(sessp);
+ if (cttyflag == (sessp->s_flags & S_CTTYREF))
+ sessp->s_flags |= S_CTTYREF;
+ else
+ doclose = 1;
+ session_unlock(sessp);
+
+ /*
+ * We have to take a reference here to make sure a close
+ * gets called during revoke. Note that once a controlling
+ * tty gets opened by this driver, the only way close will
+ * get called is when the session leader , whose controlling
+ * tty is ttyvp, exits and vnode is revoked. We cannot
+ * redirect close from this driver because underlying controlling
+ * terminal might change and close may get redirected to a
+ * wrong vnode causing panic.
+ */
+ if (doclose) {
+ devsw_unlock(dev, S_IFCHR);
+ VNOP_CLOSE(ttyvp, flag, &context);
+ devsw_lock(dev, S_IFCHR);
+ } else {
+ error = vnode_ref(ttyvp);
+ }
+ }
+out:
+ session_rele(sessp);
+
+ vnode_put(ttyvp);
kauth_cred_unref(&context.vc_ucred);
return (error);
}
-/*ARGSUSED*/
int
cttyread(__unused dev_t dev, struct uio *uio, int flag)
{
- struct proc *p = current_proc();
- register struct vnode *ttyvp = cttyvp(p);
+ vnode_t ttyvp = cttyvp(current_proc());
struct vfs_context context;
int error;
if (ttyvp == NULL)
return (EIO);
- context.vc_proc = p;
+ context.vc_thread = current_thread();
context.vc_ucred = NOCRED;
error = VNOP_READ(ttyvp, uio, flag, &context);
+ vnode_put(ttyvp);
return (error);
}
-/*ARGSUSED*/
int
cttywrite(__unused dev_t dev, struct uio *uio, int flag)
{
- struct proc *p = current_proc();
- register struct vnode *ttyvp = cttyvp(p);
+ vnode_t ttyvp = cttyvp(current_proc());
struct vfs_context context;
int error;
if (ttyvp == NULL)
return (EIO);
- context.vc_proc = p;
+ context.vc_thread = current_thread();
context.vc_ucred = NOCRED;
error = VNOP_WRITE(ttyvp, uio, flag, &context);
+ vnode_put(ttyvp);
return (error);
}
-/*ARGSUSED*/
-#ifndef NeXT
-static int
-cttyioctl(dev, cmd, addr, flag, p)
- dev_t dev;
- int cmd;
- caddr_t addr;
- int flag;
- struct proc *p;
-#else
int
-cttyioctl(__unused dev_t dev, u_long cmd, caddr_t addr, int flag,
- struct proc *p)
-#endif /* !NeXT */
+cttyioctl(__unused dev_t dev, u_long cmd, caddr_t addr, int flag, proc_t p)
{
- struct vnode *ttyvp = cttyvp(p);
+ vnode_t ttyvp = cttyvp(current_proc());
struct vfs_context context;
+ struct session *sessp;
+ int error = 0;
if (ttyvp == NULL)
return (EIO);
- if (cmd == TIOCSCTTY) /* don't allow controlling tty to be set */
- return EINVAL; /* to controlling tty -- infinite recursion */
+ if (cmd == TIOCSCTTY) { /* don't allow controlling tty to be set */
+ error = EINVAL; /* to controlling tty -- infinite recursion */
+ goto out;
+ }
if (cmd == TIOCNOTTY) {
- if (!SESS_LEADER(p)) {
- p->p_flag &= ~P_CONTROLT;
- return (0);
- } else
- return (EINVAL);
+ sessp = proc_session(p);
+ if (!SESS_LEADER(p, sessp)) {
+ OSBitAndAtomic(~((uint32_t)P_CONTROLT), &p->p_flag);
+ if (sessp != SESSION_NULL)
+ session_rele(sessp);
+ error = 0;
+ goto out;
+ } else {
+ if (sessp != SESSION_NULL)
+ session_rele(sessp);
+ error = EINVAL;
+ goto out;
+ }
}
- context.vc_proc = p;
+ context.vc_thread = current_thread();
context.vc_ucred = NOCRED;
- return (VNOP_IOCTL(ttyvp, cmd, addr, flag, &context));
+ error = VNOP_IOCTL(ttyvp, cmd, addr, flag, &context);
+out:
+ vnode_put(ttyvp);
+ return (error);
}
-/*ARGSUSED*/
int
-cttyselect(__unused dev_t dev, int flag, void* wql, struct proc *p)
+cttyselect(__unused dev_t dev, int flag, void* wql, __unused proc_t p)
{
- struct vnode *ttyvp = cttyvp(p);
+ vnode_t ttyvp = cttyvp(current_proc());
struct vfs_context context;
+ int error;
- context.vc_proc = p;
+ context.vc_thread = current_thread();
context.vc_ucred = NOCRED;
if (ttyvp == NULL)
return (1); /* try operation to get EOF/failure */
- return (VNOP_SELECT(ttyvp, flag, FREAD|FWRITE, wql, &context));
+ error = VNOP_SELECT(ttyvp, flag, FREAD|FWRITE, wql, &context);
+ vnode_put(ttyvp);
+ return (error);
}
-#ifndef NeXT
-static ctty_devsw_installed = 0;
-#ifdef DEVFS
-static void *ctty_devfs_token;
-#endif
-
-static void
-ctty_drvinit(void *unused)
+/* This returns vnode with ioref */
+static vnode_t
+cttyvp(proc_t p)
{
- dev_t dev;
-
- if( ! ctty_devsw_installed ) {
- dev = makedev(CDEV_MAJOR,0);
- cdevsw_add(&dev,&ctty_cdevsw,NULL);
- ctty_devsw_installed = 1;
-#ifdef DEVFS
- ctty_devfs_token =
- devfs_add_devswf(&ctty_cdevsw, 0, DV_CHR, 0, 0,
- 0666, "tty");
-#endif
- }
-}
+ vnode_t vp;
+ int vid;
+ struct session *sessp;
+
+ sessp = proc_session(p);
+
+ session_lock(sessp);
+ vp = (p->p_flag & P_CONTROLT ? sessp->s_ttyvp : NULLVP);
+ vid = sessp->s_ttyvid;
+ session_unlock(sessp);
-SYSINIT(cttydev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,ctty_drvinit,NULL)
+ session_rele(sessp);
+ if (vp != NULLVP) {
+ /* cannot get an IO reference, return NULLVP */
+ if (vnode_getwithvid(vp, vid) != 0)
+ vp = NULLVP;
+ }
+ return(vp);
+}
-#endif /* !NeXT */
projects / apple / xnu.git / blobdiff