Commit 87a6aca5 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

Revert "tty: Add a new VT mode which is like VT_PROCESS but doesn't require a... 


Revert "tty: Add a new VT mode which is like VT_PROCESS but doesn't require a VT_RELDISP ioctl call"

This reverts commit eec9fe7d.

Ari writes as the reason this should be reverted:
	The problems with this patch include:
	1. There's at least one subtlety I overlooked - switching
	between X servers (i.e. from one X VT to another) still requires
	the cooperation of both X servers. I was assuming that KMS
	eliminated this.
	2. It hasn't been tested at all (no X server patch exists which
	uses the new mode).

As he was the original author of the patch, I'll revert it.

Cc: Ari Entlich <atrigent@ccs.neu.edu>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent a3d3203e

drivers/char/vt_ioctl.c

+19 −20
Original line number Diff line number Diff line
@@ -888,7 +888,7 @@ int vt_ioctl(struct tty_struct *tty, struct file * file, 
			ret = -EFAULT;

			goto out;

		}

		if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS && tmp.mode != VT_PROCESS_AUTO) {

		if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) {

			ret = -EINVAL;

			goto out;

		}
@@ -1622,7 +1622,7 @@ static void complete_change_console(struct vc_data *vc) 
	 * telling it that it has acquired. Also check if it has died and

	 * clean up (similar to logic employed in change_console())

	 */

	if (vc->vt_mode.mode == VT_PROCESS || vc->vt_mode.mode == VT_PROCESS_AUTO) {

	if (vc->vt_mode.mode == VT_PROCESS) {

		/*

		 * Send the signal as privileged - kill_pid() will

		 * tell us if the process has gone or something else
@@ -1682,7 +1682,7 @@ void change_console(struct vc_data *new_vc) 
	 * vt to auto control.

	 */

	vc = vc_cons[fg_console].d;

	if (vc->vt_mode.mode == VT_PROCESS || vc->vt_mode.mode == VT_PROCESS_AUTO) {

	if (vc->vt_mode.mode == VT_PROCESS) {

		/*

		 * Send the signal as privileged - kill_pid() will

		 * tell us if the process has gone or something else
@@ -1693,14 +1693,14 @@ void change_console(struct vc_data *new_vc) 
		 */

		vc->vt_newvt = new_vc->vc_num;

		if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {

			if(vc->vt_mode.mode == VT_PROCESS)

			/*

			 * It worked. Mark the vt to switch to and

			 * return. The process needs to send us a

			 * VT_RELDISP ioctl to complete the switch.

			 */

			return;

		} else {

		}



		/*

		 * The controlling process has died, so we revert back to

		 * normal operation. In this case, we'll also change back
@@ -1711,10 +1711,9 @@ void change_console(struct vc_data *new_vc) 
		 * to account for and tracking tty count may be undesirable.

		 */

		reset_vc(vc);

		}



		/*

		 * Fall through to normal (VT_AUTO and VT_PROCESS_AUTO) handling of the switch...

		 * Fall through to normal (VT_AUTO) handling of the switch...

		 */

	}

include/linux/vt.h

+1 −2
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ struct vt_mode { 
#define VT_SETMODE	0x5602	/* set mode of active vt */

#define		VT_AUTO		0x00	/* auto vt switching */

#define		VT_PROCESS	0x01	/* process controls switching */

#define		VT_PROCESS_AUTO 0x02	/* process is notified of switching */

#define		VT_ACKACQ	0x02	/* acknowledge switch */



struct vt_stat {

	unsigned short v_active;	/* active vt */
@@ -38,7 +38,6 @@ struct vt_stat { 
#define VT_SENDSIG	0x5604	/* signal to send to bitmask of vts */



#define VT_RELDISP	0x5605	/* release display */

#define		VT_ACKACQ	0x02	/* acknowledge switch */



#define VT_ACTIVATE	0x5606	/* make vt active */

#define VT_WAITACTIVE	0x5607	/* wait for vt active */

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