From 87a6aca504d65f242589583e04df5e74b5eae1fe Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 15 Mar 2010 17:14:15 -0700 Subject: [PATCH] Revert "tty: Add a new VT mode which is like VT_PROCESS but doesn't require a VT_RELDISP ioctl call" This reverts commit eec9fe7d1ab4a0dfac4cb43047a7657fffd0002f. 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 Cc: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/char/vt_ioctl.c | 39 +++++++++++++++++++-------------------- include/linux/vt.h | 3 +-- 2 files changed, 20 insertions(+), 22 deletions(-) diff --git a/drivers/char/vt_ioctl.c b/drivers/char/vt_ioctl.c index 87778dcf8727..6aa10284104a 100644 --- a/drivers/char/vt_ioctl.c +++ b/drivers/char/vt_ioctl.c @@ -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 @@ -1693,28 +1693,27 @@ 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 - * to KD_TEXT mode. I'm not sure if this is strictly correct - * but it saves the agony when the X server dies and the screen - * remains blanked due to KD_GRAPHICS! It would be nice to do - * this outside of VT_PROCESS but there is no single process - * to account for and tracking tty count may be undesirable. + * It worked. Mark the vt to switch to and + * return. The process needs to send us a + * VT_RELDISP ioctl to complete the switch. */ - reset_vc(vc); + return; } /* - * Fall through to normal (VT_AUTO and VT_PROCESS_AUTO) handling of the switch... + * The controlling process has died, so we revert back to + * normal operation. In this case, we'll also change back + * to KD_TEXT mode. I'm not sure if this is strictly correct + * but it saves the agony when the X server dies and the screen + * remains blanked due to KD_GRAPHICS! It would be nice to do + * this outside of VT_PROCESS but there is no single process + * to account for and tracking tty count may be undesirable. + */ + reset_vc(vc); + + /* + * Fall through to normal (VT_AUTO) handling of the switch... */ } diff --git a/include/linux/vt.h b/include/linux/vt.h index 778b7b2a47d4..d5dd0bc408fd 100644 --- a/include/linux/vt.h +++ b/include/linux/vt.h @@ -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 */ -- 2.30.2