From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 355A2C4167E for ; Wed, 6 Apr 2022 03:16:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1851371AbiDFDOD (ORCPT ); Tue, 5 Apr 2022 23:14:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1847103AbiDFCM4 (ORCPT ); Tue, 5 Apr 2022 22:12:56 -0400 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CC231B085F for ; Tue, 5 Apr 2022 16:35:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1649201711; x=1680737711; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=0oGzRGaNHs6zSiTU7rw2R8nyUJRF2pFTx/tgJjHLE5g=; b=aAp8q9Vg67GnARUl2WMfDEqLwIcAq4zXTolRh6mCbbrd0cUJZmoRKSkl AFoRi84gtJ/q+utlwBqLln4rnUi+AQSNfhXoLPY6dW8pfCyPdWnynqL4D zvUKn/0CYPGHUjEeBzbBtkuP3v0azE1ZMg2L/zJ4MH9e1frJy/szFqCgq aQHDHYKPDtiKPL0u504DNurQospHwZBMMOBOwvYs7iFJlXRpAZO33Su44 glylz/AOGO9Mjuj7WR3Y16zW8BuSOIUPO2tOz+a29oPaQQ1o2lagfA6S1 FOw6tB0pq7YkgL6Clax+oMGfjck1PlMoz7AooWkjkRaMkxbzxSfX1AsaW g==; X-IronPort-AV: E=McAfee;i="6200,9189,10308"; a="285854430" X-IronPort-AV: E=Sophos;i="5.90,238,1643702400"; d="scan'208";a="285854430" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Apr 2022 16:34:54 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,238,1643702400"; d="scan'208";a="697135343" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga001.fm.intel.com with ESMTP; 05 Apr 2022 16:34:47 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 43853BD9; Wed, 6 Apr 2022 02:29:46 +0300 (EEST) From: "Kirill A. Shutemov" To: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@intel.com, luto@kernel.org, peterz@infradead.org Cc: sathyanarayanan.kuppuswamy@linux.intel.com, aarcange@redhat.com, ak@linux.intel.com, dan.j.williams@intel.com, david@redhat.com, hpa@zytor.com, jgross@suse.com, jmattson@google.com, joro@8bytes.org, jpoimboe@redhat.com, knsathya@kernel.org, pbonzini@redhat.com, sdeep@vmware.com, seanjc@google.com, tony.luck@intel.com, vkuznets@redhat.com, wanpengli@tencent.com, thomas.lendacky@amd.com, brijesh.singh@amd.com, x86@kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , Dave Hansen Subject: [PATCHv8 15/30] x86/boot: Port I/O: allow to hook up alternative helpers Date: Wed, 6 Apr 2022 02:29:24 +0300 Message-Id: <20220405232939.73860-16-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405232939.73860-1-kirill.shutemov@linux.intel.com> References: <20220405232939.73860-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Port I/O instructions trigger #VE in the TDX environment. In response to the exception, kernel emulates these instructions using hypercalls. But during early boot, on the decompression stage, it is cumbersome to deal with #VE. It is cleaner to go to hypercalls directly, bypassing #VE handling. Add a way to hook up alternative port I/O helpers in the boot stub with a new pio_ops structure. For now, set the ops structure to just call the normal I/O operation functions. out*()/in*() macros redefined to use pio_ops callbacks. It eliminates need in changing call sites. io_delay() changed to use port I/O helper instead of inline assembly. Signed-off-by: Kirill A. Shutemov Reviewed-by: Dave Hansen --- arch/x86/boot/boot.h | 4 ++-- arch/x86/boot/compressed/misc.c | 4 ++++ arch/x86/boot/compressed/misc.h | 2 +- arch/x86/boot/io.h | 41 +++++++++++++++++++++++++++++++++ arch/x86/boot/main.c | 4 ++++ arch/x86/realmode/rm/wakemain.c | 4 ++++ 6 files changed, 56 insertions(+), 3 deletions(-) create mode 100644 arch/x86/boot/io.h diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h index 22a474c5b3e8..b42b91606ca8 100644 --- a/arch/x86/boot/boot.h +++ b/arch/x86/boot/boot.h @@ -23,10 +23,10 @@ #include #include #include -#include #include "bitops.h" #include "ctype.h" #include "cpuflags.h" +#include "io.h" /* Useful macros */ #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) @@ -39,7 +39,7 @@ extern struct boot_params boot_params; static inline void io_delay(void) { const u16 DELAY_PORT = 0x80; - asm volatile("outb %%al,%0" : : "dN" (DELAY_PORT)); + outb(0, DELAY_PORT); } /* These functions are used to reference data in other segments. */ diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index e8142e977ddb..fa8969fad011 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -48,6 +48,8 @@ void *memmove(void *dest, const void *src, size_t n); */ struct boot_params *boot_params; +struct port_io_ops pio_ops; + memptr free_mem_ptr; memptr free_mem_end_ptr; @@ -371,6 +373,8 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, lines = boot_params->screen_info.orig_video_lines; cols = boot_params->screen_info.orig_video_cols; + init_default_io_ops(); + /* * Detect TDX guest environment. * diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 8a253e85f990..ea71cf3d64e1 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -26,7 +26,6 @@ #include #include #include -#include #include "tdx.h" @@ -35,6 +34,7 @@ #define BOOT_BOOT_H #include "../ctype.h" +#include "../io.h" #ifdef CONFIG_X86_64 #define memptr long diff --git a/arch/x86/boot/io.h b/arch/x86/boot/io.h new file mode 100644 index 000000000000..110880907f87 --- /dev/null +++ b/arch/x86/boot/io.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef BOOT_IO_H +#define BOOT_IO_H + +#include + +#undef inb +#undef inw +#undef inl +#undef outb +#undef outw +#undef outl + +struct port_io_ops { + u8 (*f_inb)(u16 port); + void (*f_outb)(u8 v, u16 port); + void (*f_outw)(u16 v, u16 port); +}; + +extern struct port_io_ops pio_ops; + +/* + * Use the normal I/O instructions by default. + * TDX guests override these to use hypercalls. + */ +static inline void init_default_io_ops(void) +{ + pio_ops.f_inb = __inb; + pio_ops.f_outb = __outb; + pio_ops.f_outw = __outw; +} + +/* + * Redirect port I/O operations via pio_ops callbacks. + * TDX guests override these callbacks with TDX-specific helpers. + */ +#define inb pio_ops.f_inb +#define outb pio_ops.f_outb +#define outw pio_ops.f_outw + +#endif diff --git a/arch/x86/boot/main.c b/arch/x86/boot/main.c index e3add857c2c9..1202d4f8a390 100644 --- a/arch/x86/boot/main.c +++ b/arch/x86/boot/main.c @@ -17,6 +17,8 @@ struct boot_params boot_params __attribute__((aligned(16))); +struct port_io_ops pio_ops; + char *HEAP = _end; char *heap_end = _end; /* Default end of heap = no heap */ @@ -133,6 +135,8 @@ static void init_heap(void) void main(void) { + init_default_io_ops(); + /* First, copy the boot header into the "zeropage" */ copy_boot_params(); diff --git a/arch/x86/realmode/rm/wakemain.c b/arch/x86/realmode/rm/wakemain.c index 1d6437e6d2ba..a6f4d8388ad8 100644 --- a/arch/x86/realmode/rm/wakemain.c +++ b/arch/x86/realmode/rm/wakemain.c @@ -62,8 +62,12 @@ static void send_morse(const char *pattern) } } +struct port_io_ops pio_ops; + void main(void) { + init_default_io_ops(); + /* Kill machine if structures are wrong */ if (wakeup_header.real_magic != 0x12345678) while (1) -- 2.35.1