This is what was "fdfix2.patch," a fix for fd sharing. It's pretty

far-reaching in fd-land, so you'll want to consult the code for
changes.  The biggest change is that now, you don't use
	fp->f_ops->fo_foo(fp, bar)
but instead
	fo_foo(fp, bar),
which increments and decrements the fp refcount upon entry and exit.
Two new calls, fhold() and fdrop(), are provided.  Each does what it
seems like it should, and if fdrop() brings the refcount to zero, the
fd is freed as well.

Thanks to peter ("to hell with it, it looks ok to me.") for his review.
Thanks to msmith for keeping me from putting locks everywhere :)

Reviewed by:	peter

1 files changed, 19 insertions, 21 deletions

diff --git a/sys/compat/linux/linux_ioctl.c b/sys/compat/linux/linux_ioctl.c
index 8507ade..d071bcd 100644
--- a/sys/compat/linux/linux_ioctl.c
+++ b/sys/compat/linux/linux_ioctl.c
@@ -539,7 +539,6 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
     struct linux_termio linux_termio;
     struct filedesc *fdp = p->p_fd;
     struct file *fp;
-    int (*func)(struct file *fp, u_long com, caddr_t data, struct proc *p);
     int bsd_line, linux_line;
     int error;
 
@@ -555,11 +554,10 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	return EBADF;
     }
 
-    func = fp->f_ops->fo_ioctl;
     switch (args->cmd & 0xffff) {
 
     case LINUX_TCGETA:
-	if ((error = (*func)(fp, TIOCGETA, (caddr_t)&bsd_termios, p)) != 0)
+	if ((error = fo_ioctl(fp, TIOCGETA, (caddr_t)&bsd_termios, p)) != 0)
 	    return error;
 	bsd_to_linux_termio(&bsd_termios, &linux_termio);
 	return copyout((caddr_t)&linux_termio, (caddr_t)args->arg,
@@ -570,24 +568,24 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	if (error)
 	    return error;
 	linux_to_bsd_termio(&linux_termio, &bsd_termios);
-	return (*func)(fp, TIOCSETA, (caddr_t)&bsd_termios, p);
+	return fo_ioctl(fp, TIOCSETA, (caddr_t)&bsd_termios, p);
 
     case LINUX_TCSETAW:
 	error = copyin((caddr_t)args->arg, &linux_termio, sizeof(linux_termio));
 	if (error)
 	    return error;
 	linux_to_bsd_termio(&linux_termio, &bsd_termios);
-	return (*func)(fp, TIOCSETAW, (caddr_t)&bsd_termios, p);
+	return fo_ioctl(fp, TIOCSETAW, (caddr_t)&bsd_termios, p);
 
     case LINUX_TCSETAF:
 	error = copyin((caddr_t)args->arg, &linux_termio, sizeof(linux_termio));
 	if (error)
 	    return error;
 	linux_to_bsd_termio(&linux_termio, &bsd_termios);
-	return (*func)(fp, TIOCSETAF, (caddr_t)&bsd_termios, p);
+	return fo_ioctl(fp, TIOCSETAF, (caddr_t)&bsd_termios, p);
 
     case LINUX_TCGETS:
-	if ((error = (*func)(fp, TIOCGETA, (caddr_t)&bsd_termios, p)) != 0)
+	if ((error = fo_ioctl(fp, TIOCGETA, (caddr_t)&bsd_termios, p)) != 0)
 	    return error;
 	bsd_to_linux_termios(&bsd_termios, &linux_termios);
 	return copyout((caddr_t)&linux_termios, (caddr_t)args->arg,
@@ -599,7 +597,7 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	if (error)
 	    return error;
 	linux_to_bsd_termios(&linux_termios, &bsd_termios);
-	return (*func)(fp, TIOCSETA, (caddr_t)&bsd_termios, p);
+	return fo_ioctl(fp, TIOCSETA, (caddr_t)&bsd_termios, p);
 
     case LINUX_TCSETSW:
 	error = copyin((caddr_t)args->arg, &linux_termios,
@@ -607,7 +605,7 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	if (error)
 	    return error;
 	linux_to_bsd_termios(&linux_termios, &bsd_termios);
-	return (*func)(fp, TIOCSETAW, (caddr_t)&bsd_termios, p);
+	return fo_ioctl(fp, TIOCSETAW, (caddr_t)&bsd_termios, p);
 
     case LINUX_TCSETSF:
 	error = copyin((caddr_t)args->arg, &linux_termios,
@@ -615,7 +613,7 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	if (error)
 	    return error;
 	linux_to_bsd_termios(&linux_termios, &bsd_termios);
-	return (*func)(fp, TIOCSETAF, (caddr_t)&bsd_termios, p);
+	return fo_ioctl(fp, TIOCSETAF, (caddr_t)&bsd_termios, p);
 	    
     case LINUX_TIOCGPGRP:
 	args->cmd = TIOCGPGRP;
@@ -773,20 +771,20 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	switch (args->arg) {
 	case LINUX_N_TTY:
 	    bsd_line = TTYDISC;
-	    return (*func)(fp, TIOCSETD, (caddr_t)&bsd_line, p);
+	    return fo_ioctl(fp, TIOCSETD, (caddr_t)&bsd_line, p);
 	case LINUX_N_SLIP:
 	    bsd_line = SLIPDISC;
-	    return (*func)(fp, TIOCSETD, (caddr_t)&bsd_line, p);
+	    return fo_ioctl(fp, TIOCSETD, (caddr_t)&bsd_line, p);
 	case LINUX_N_PPP:
 	    bsd_line = PPPDISC;
-	    return (*func)(fp, TIOCSETD, (caddr_t)&bsd_line, p);
+	    return fo_ioctl(fp, TIOCSETD, (caddr_t)&bsd_line, p);
 	default:
 	    return EINVAL;
 	}
 
     case LINUX_TIOCGETD:
 	bsd_line = TTYDISC;
-	error =(*func)(fp, TIOCGETD, (caddr_t)&bsd_line, p);
+	error = fo_ioctl(fp, TIOCGETD, (caddr_t)&bsd_line, p);
 	if (error)
 	    return error;
 	switch (bsd_line) {
@@ -1048,7 +1046,7 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
       case LINUX_TCION: {
 	      u_char c;
 	      struct write_args wr;
-	      error = (*func)(fp, TIOCGETA, (caddr_t)&bsd_termios, p);
+	      error = fo_ioctl(fp, TIOCGETA, (caddr_t)&bsd_termios, p);
               if (error != 0)
 		      return error;
 	      c = bsd_termios.c_cc[args->arg == LINUX_TCIOFF ? VSTOP : VSTART];
@@ -1135,13 +1133,13 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	switch (args->arg) {
 	case LINUX_KBD_RAW:
 	    kbdmode = K_RAW;
-	    return (*func)(fp, KDSKBMODE, (caddr_t)&kbdmode, p);
+	    return fo_ioctl(fp, KDSKBMODE, (caddr_t)&kbdmode, p);
 	case LINUX_KBD_XLATE:  
 	    kbdmode = K_XLATE;
-	    return (*func)(fp, KDSKBMODE , (caddr_t)&kbdmode, p);
+	    return fo_ioctl(fp, KDSKBMODE , (caddr_t)&kbdmode, p);
 	case LINUX_KBD_MEDIUMRAW:
 	    kbdmode = K_RAW;
-	    return (*func)(fp, KDSKBMODE , (caddr_t)&kbdmode, p);
+	    return fo_ioctl(fp, KDSKBMODE , (caddr_t)&kbdmode, p);
 	default:
 	    return EINVAL;
 	}
@@ -1207,7 +1205,7 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
     case LINUX_CDROMREADTOCHDR: {
 	struct ioc_toc_header th;
 	struct linux_cdrom_tochdr lth;
-	error = (*func)(fp, CDIOREADTOCHEADER, (caddr_t)&th, p);
+	error = fo_ioctl(fp, CDIOREADTOCHEADER, (caddr_t)&th, p);
 	if (!error) {
 	    lth.cdth_trk0 = th.starting_track;
 	    lth.cdth_trk1 = th.ending_track;
@@ -1222,7 +1220,7 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	struct ioc_read_toc_single_entry irtse;
 	irtse.address_format = ltep->cdte_format;
 	irtse.track = ltep->cdte_track;
-	error = (*func)(fp, CDIOREADTOCENTRY, (caddr_t)&irtse, p);
+	error = fo_ioctl(fp, CDIOREADTOCENTRY, (caddr_t)&irtse, p);
 	if (!error) {
 	    lte = *ltep;
 	    lte.cdte_ctrl = irtse.entry.control;
@@ -1248,7 +1246,7 @@ linux_ioctl(struct proc *p, struct linux_ioctl_args *args)
 	bsdsc.data_format = CD_CURRENT_POSITION;
 	bsdsc.data_len = sizeof(struct cd_sub_channel_info);
 	bsdsc.data = bsdinfo;
-	error = (*func)(fp, CDIOCREADSUBCHANNEL, (caddr_t)&bsdsc, p);
+	error = fo_ioctl(fp, CDIOCREADSUBCHANNEL, (caddr_t)&bsdsc, p);
 	if (error)
 	    return error;