Module Name: src Committed By: riz Date: Mon Aug 20 19:15:36 UTC 2012
Modified Files: src/sys/kern [netbsd-6]: tty.c Log Message: Pull up following revision(s) (requested by christos in ticket #516): sys/kern/tty.c: revision 1.251 sys/kern/tty.c: revision 1.252 sys/kern/tty.c: revision 1.253 Better (not racy fix) from Paul Goyette. Use the queue of the tty not garbage from the stack (Paul Goyette) PR/46780: Dennis Ferguson: Take the easy way out and return EBUSY when changing the queue size if the output queue is not empty. Other solutions seemed too complex/fragile. To generate a diff of this commit: cvs rdiff -u -r1.249.8.1 -r1.249.8.2 src/sys/kern/tty.c Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files.
Modified files: Index: src/sys/kern/tty.c diff -u src/sys/kern/tty.c:1.249.8.1 src/sys/kern/tty.c:1.249.8.2 --- src/sys/kern/tty.c:1.249.8.1 Mon Mar 19 23:23:10 2012 +++ src/sys/kern/tty.c Mon Aug 20 19:15:36 2012 @@ -1,4 +1,4 @@ -/* $NetBSD: tty.c,v 1.249.8.1 2012/03/19 23:23:10 riz Exp $ */ +/* $NetBSD: tty.c,v 1.249.8.2 2012/08/20 19:15:36 riz Exp $ */ /*- * Copyright (c) 2008 The NetBSD Foundation, Inc. @@ -63,7 +63,7 @@ */ #include <sys/cdefs.h> -__KERNEL_RCSID(0, "$NetBSD: tty.c,v 1.249.8.1 2012/03/19 23:23:10 riz Exp $"); +__KERNEL_RCSID(0, "$NetBSD: tty.c,v 1.249.8.2 2012/08/20 19:15:36 riz Exp $"); #include <sys/param.h> #include <sys/systm.h> @@ -224,7 +224,7 @@ tty_get_qsize(int *qsize, int newsize) return 0; } -static void +static int tty_set_qsize(struct tty *tp, int newsize) { struct clist rawq, canq, outq; @@ -236,6 +236,14 @@ tty_set_qsize(struct tty *tp, int newsiz mutex_spin_enter(&tty_lock); + if (tp->t_outq.c_cc != 0) { + mutex_spin_exit(&tty_lock); + clfree(&rawq); + clfree(&canq); + clfree(&outq); + return EBUSY; + } + orawq = tp->t_rawq; ocanq = tp->t_canq; ooutq = tp->t_outq; @@ -252,6 +260,8 @@ tty_set_qsize(struct tty *tp, int newsiz clfree(&orawq); clfree(&ocanq); clfree(&ooutq); + + return 0; } static int @@ -1350,7 +1360,7 @@ ttioctl(struct tty *tp, u_long cmd, void case TIOCSQSIZE: if ((error = tty_get_qsize(&s, *(int *)data)) == 0 && s != tp->t_qsize) - tty_set_qsize(tp, s); + error = tty_set_qsize(tp, s); return error; default: /* We may have to load the compat module for this. */