From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760614AbcBYMLl (ORCPT ); Thu, 25 Feb 2016 07:11:41 -0500 Received: from smtp02.citrix.com ([66.165.176.63]:53426 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760249AbcBYMLe (ORCPT ); Thu, 25 Feb 2016 07:11:34 -0500 X-IronPort-AV: E=Sophos;i="5.22,498,1449532800"; d="scan'208";a="341041047" From: Stefano Stabellini To: CC: , , , , , Stefano Stabellini Subject: [PATCH v2 3/3] hvc_xen: make early_printk work with HVM guests Date: Thu, 25 Feb 2016 12:10:39 +0000 Message-ID: <1456402239-4179-3-git-send-email-stefano.stabellini@eu.citrix.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Refactor the existing code in xen_raw_console_write to get the generic early_printk console work with HVM guests. Take the opportunity to replace the outb loop with a single outsb call to reduce the number of vmexit. Signed-off-by: Stefano Stabellini --- drivers/tty/hvc/hvc_xen.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c index bf787aa..a1c3746 100644 --- a/drivers/tty/hvc/hvc_xen.c +++ b/drivers/tty/hvc/hvc_xen.c @@ -605,6 +605,16 @@ static int xen_cons_init(void) } console_initcall(xen_cons_init); +#ifdef CONFIG_X86 +static void xen_hvm_early_write(uint32_t vtermno, const char *str, int len) +{ + if (xen_cpuid_base()) + outsb(0xe9, str, len); +} +#else +static void xen_hvm_early_write(uint32_t vtermno, const char *str, int len) { } +#endif + #ifdef CONFIG_EARLY_PRINTK static int __init xenboot_setup_console(struct console *console, char *string) { @@ -624,8 +634,10 @@ static void xenboot_write_console(struct console *console, const char *string, unsigned int linelen, off = 0; const char *pos; - if (!xen_pv_domain()) + if (!xen_pv_domain()) { + xen_hvm_early_write(0, string, len); return; + } dom0_write_console(0, string, len); @@ -661,17 +673,10 @@ void xen_raw_console_write(const char *str) if (xen_domain()) { rc = dom0_write_console(0, str, len); -#ifdef CONFIG_X86 - if (rc == -ENOSYS && xen_hvm_domain()) - goto outb_print; - - } else if (xen_cpuid_base()) { - int i; -outb_print: - for (i = 0; i < len; i++) - outb(str[i], 0xe9); -#endif + if (rc != -ENOSYS || !xen_hvm_domain()) + return; } + xen_hvm_early_write(0, str, len); } void xen_raw_printk(const char *fmt, ...) -- 1.7.10.4