From patchwork Tue May 30 06:13:07 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 13259232 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 86411C7EE2E for ; Tue, 30 May 2023 06:13:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229701AbjE3GNM (ORCPT ); Tue, 30 May 2023 02:13:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53988 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229551AbjE3GNL (ORCPT ); Tue, 30 May 2023 02:13:11 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E586BEC; Mon, 29 May 2023 23:13:09 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8021162A32; Tue, 30 May 2023 06:13:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6328AC433D2; Tue, 30 May 2023 06:13:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685427188; bh=orvAfFB1al0I5E+N/dd1jRm8DcYqs+dBcPiT7570GoU=; h=From:To:Subject:Date:From; b=QQbYKyy5q6xxFFpacZ8k4ySj1uQTgCwOxQNXDfmXymFDKxReknTz+B3zZA135hh9H qOAMtCtVhbXu5lelm/ha6uEQl1JXlwsnXfSy9okbgOKbPklJ3M9jBxOE1ByEvXntLs XAM21wCS8hUkstYFU/TRkKzJ1V63yxSM/eOcgFemzqX3wozdXLY2H1dNh5BXE95Whm JomLYM6XUWDsXlFpUV0Z5Ghz9W+B386LRtn5dLHDwpkhz98RsCKyjuL/0CiTR4TI08 Qgu4koHS27zmFXK/yiTCXNcZq5kItFjcH8R1xTXe9TNjR96hVsh+l6Zf0EO7KETk8b lj6RsqmFe+pag== From: Damien Le Moal To: "Martin K . Petersen" , linux-scsi@vger.kernel.org, Jens Axboe , linux-block@vger.kernel.org Subject: [PATCH] block: improve ioprio value validity checks Date: Tue, 30 May 2023 15:13:07 +0900 Message-Id: <20230530061307.525644-1-dlemoal@kernel.org> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org The introduction of the macro IOPRIO_PRIO_LEVEL() in commit eca2040972b4 ("scsi: block: ioprio: Clean up interface definition") results in an iopriority level to always be masked using the macro IOPRIO_LEVEL_MASK, and thus to the kernel always seeing an acceptable value for an I/O priority level when checked in ioprio_check_cap(). Before this patch, this function would return an error for some (but not all) invalid values for a level valid range of [0..7]. Restore and improve the detection of invalid priority levels by introducing the inline function ioprio_value() to check an ioprio class, level and hint value before combining these fields into a single value to be used with ioprio_set() or AIOs. If an invalid value for the class, level or hint of an ioprio is detected, ioprio_value() returns an ioprio using the class IOPRIO_CLASS_INVALID, indicating an invalid value and causing ioprio_check_cap() to return -EINVAL. Fixes: 6c913257226a ("scsi: block: Introduce ioprio hints") Fixes: eca2040972b4 ("scsi: block: ioprio: Clean up interface definition") Signed-off-by: Damien Le Moal Reviewed-by: Niklas Cassel --- block/ioprio.c | 1 + include/uapi/linux/ioprio.h | 47 +++++++++++++++++++++++-------------- 2 files changed, 31 insertions(+), 17 deletions(-) diff --git a/block/ioprio.c b/block/ioprio.c index f0d9e818abc5..b5a942519a79 100644 --- a/block/ioprio.c +++ b/block/ioprio.c @@ -58,6 +58,7 @@ int ioprio_check_cap(int ioprio) if (level) return -EINVAL; break; + case IOPRIO_CLASS_INVALID: default: return -EINVAL; } diff --git a/include/uapi/linux/ioprio.h b/include/uapi/linux/ioprio.h index 607c7617b9d2..7310449c0178 100644 --- a/include/uapi/linux/ioprio.h +++ b/include/uapi/linux/ioprio.h @@ -6,15 +6,13 @@ * Gives us 8 prio classes with 13-bits of data for each class */ #define IOPRIO_CLASS_SHIFT 13 -#define IOPRIO_CLASS_MASK 0x07 +#define IOPRIO_NR_CLASSES 8 +#define IOPRIO_CLASS_MASK (IOPRIO_NR_CLASSES - 1) #define IOPRIO_PRIO_MASK ((1UL << IOPRIO_CLASS_SHIFT) - 1) #define IOPRIO_PRIO_CLASS(ioprio) \ (((ioprio) >> IOPRIO_CLASS_SHIFT) & IOPRIO_CLASS_MASK) #define IOPRIO_PRIO_DATA(ioprio) ((ioprio) & IOPRIO_PRIO_MASK) -#define IOPRIO_PRIO_VALUE(class, data) \ - ((((class) & IOPRIO_CLASS_MASK) << IOPRIO_CLASS_SHIFT) | \ - ((data) & IOPRIO_PRIO_MASK)) /* * These are the io priority classes as implemented by the BFQ and mq-deadline @@ -25,10 +23,13 @@ * served when no one else is using the disk. */ enum { - IOPRIO_CLASS_NONE, - IOPRIO_CLASS_RT, - IOPRIO_CLASS_BE, - IOPRIO_CLASS_IDLE, + IOPRIO_CLASS_NONE = 0, + IOPRIO_CLASS_RT = 1, + IOPRIO_CLASS_BE = 2, + IOPRIO_CLASS_IDLE = 3, + + /* Special class to indicate an invalid ioprio value */ + IOPRIO_CLASS_INVALID = 7, }; /* @@ -73,15 +74,6 @@ enum { #define IOPRIO_PRIO_HINT(ioprio) \ (((ioprio) >> IOPRIO_HINT_SHIFT) & IOPRIO_HINT_MASK) -/* - * Alternate macro for IOPRIO_PRIO_VALUE() to define an IO priority with - * a class, level and hint. - */ -#define IOPRIO_PRIO_VALUE_HINT(class, level, hint) \ - ((((class) & IOPRIO_CLASS_MASK) << IOPRIO_CLASS_SHIFT) | \ - (((hint) & IOPRIO_HINT_MASK) << IOPRIO_HINT_SHIFT) | \ - ((level) & IOPRIO_LEVEL_MASK)) - /* * IO hints. */ @@ -107,4 +99,25 @@ enum { IOPRIO_HINT_DEV_DURATION_LIMIT_7 = 7, }; +#define IOPRIO_BAD_VALUE(val, max) ((val) < 0 || (val) >= (max)) + +/* + * Return an I/O priority value based on a class, a level and a hint. + */ +static __always_inline __u16 ioprio_value(int class, int level, int hint) +{ + if (IOPRIO_BAD_VALUE(class, IOPRIO_NR_CLASSES) || + IOPRIO_BAD_VALUE(level, IOPRIO_NR_LEVELS) || + IOPRIO_BAD_VALUE(hint, IOPRIO_NR_HINTS)) + return IOPRIO_CLASS_INVALID << IOPRIO_CLASS_SHIFT; + + return (class << IOPRIO_CLASS_SHIFT) | + (hint << IOPRIO_HINT_SHIFT) | level; +} + +#define IOPRIO_PRIO_VALUE(class, level) \ + ioprio_value(class, level, IOPRIO_HINT_NONE) +#define IOPRIO_PRIO_VALUE_HINT(class, level, hint) \ + ioprio_value(class, level, hint) + #endif /* _UAPI_LINUX_IOPRIO_H */