From patchwork Fri Aug 6 05:11:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 12422729 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 296E8C432BE for ; Fri, 6 Aug 2021 05:11:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0683E611C9 for ; Fri, 6 Aug 2021 05:11:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242984AbhHFFMC (ORCPT ); Fri, 6 Aug 2021 01:12:02 -0400 Received: from esa5.hgst.iphmx.com ([216.71.153.144]:64546 "EHLO esa5.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242906AbhHFFMB (ORCPT ); Fri, 6 Aug 2021 01:12:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1628226705; x=1659762705; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=yF/LJ6VOE4VEWoTqOdUoMSQXN8kTNgY8NlgLx4xkskI=; b=fhN5l2VICSYtSuFIFbH+7tde8HL7p+0+3SqyzvOKoZFEeuN8Swfm9GFv C4v+nWgw0xrcefE9+qdwu7LXmG1q0F0bKoKxq1yYk2myteLWWlL3PGWrd VcEbmvDy0jEaJ5Q921uFGreuC0LWs7VrSdEKwQwY7KwZYRiAngN+ZCxXy 4ZAIKfq1AH2uFBWpwzcObatoO5dARC8O+1MHJRV/nSVsIePYZ5r5UcSac Di77cdIyHJwu5ocgsCLM6fNKiYxsT6Y8p6ttqOHYTYtcqN+MAJEv0nbvz 2i9LipclNqJvUky1lIfKGTydFLCjDjysIEr9jiQ+F6dLl54n/Vug7Z5Bi A==; X-IronPort-AV: E=Sophos;i="5.84,299,1620662400"; d="scan'208";a="176473066" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 06 Aug 2021 13:11:45 +0800 IronPort-SDR: lEKf7rrC7NZd3bUToxO9R3COxApIkKo/A5Wte2eZ7om38zgHEENdf2HYdSodMgYbH6vey+C9m0 USP/nVYwZo0tUeSy8r0FXYT3bCw8LXgtebDCWXNQR/Z4f15lHWC3jowFHyrvwCuu3M3OszjyFs D7gjJysEM+1lj/0JYkUmkppoWUjBf1wehbwf1nrOshT0HCRAM02S8sBHtdhONdAnJERFxd94SN +qHowpqpfEnDCd9IyOdqfDHt8Pmy+ngUPOErMOe5ER+VN8oBag+8Kgf0mq2ayprMYilI/ke28S VXjBsN06QFkj10THz7M08nmS Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Aug 2021 21:49:15 -0700 IronPort-SDR: w8bV4j/ECwEnGb61JKPkK60ne7QZHiyOx4aiWPBKHc+/Lwy3T7i8PD2dgRL7CYtK930rAjoRuF 5/pTFPHrvdZmAN56NEOh78/jBMsLjG0HGiwX81GtWrDlym4wBDdBgDXqYWnrZYJ02yE1nlqdCl L6kz2o/M7pbjVMCB75iqE4K8LRq9bRWHe8OqCV/BlBjLsed/1e3E0RyfxRn6U++DEygyqBC9Vx qDRmYHe9UNHk7x7x/M7uaLHmKdQvFNo/C+k2qqLiHpR5FduaUBBDZ6MfQtL0MHQIafShBwgOUp HKI= WDCIronportException: Internal Received: from washi.fujisawa.hgst.com ([10.149.53.254]) by uls-op-cesaip01.wdc.com with ESMTP; 05 Aug 2021 22:11:45 -0700 From: Damien Le Moal To: Jens Axboe , linux-block@vger.kernel.org, Paolo Valente , linux-f2fs-devel@lists.sourceforge.net, Jaegeuk Kim , Chao Yu Subject: [PATCH v2 2/4] block: fix ioprio interface Date: Fri, 6 Aug 2021 14:11:38 +0900 Message-Id: <20210806051140.301127-3-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210806051140.301127-1-damien.lemoal@wdc.com> References: <20210806051140.301127-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org An iocb aio_reqprio field is 16-bits (u16) but often handled as an int in the block layer. E.g. ioprio_check_cap() takes an int as argument. With such implicit int casting function calls, the upper 16-bits of the int argument may be left uninitialized by the compiler, resulting in invalid values for the IOPRIO_PRIO_CLASS() macro (garbage upper bits) and in an error return for functions such as ioprio_check_cap(). Fix this by masking the result of the shift by IOPRIO_CLASS_SHIFT bits in the IOPRIO_PRIO_CLASS() macro. The new macro IOPRIO_CLASS_MASK defines the 3-bits mask for the priority class. While at it, cleanup the following: * Apply the mask IOPRIO_PRIO_MASK to the data argument of the IOPRIO_PRIO_VALUE() macro to ignore upper bits of the data value. * Remove unnecessary parenthesis around fixed values in the macro definitions in include/uapi/linux/ioprio.h. * Update the outdated mention of CFQ in the comment describing priority classes and instead mention BFQ and mq-deadline. * Change the argument name of the IOPRIO_PRIO_CLASS() and IOPRIO_PRIO_DATA() macros from "mask" to "ioprio" to reflect the fact that an IO priority value should be passed rather than a mask. * Change the ioprio_valid() macro into an inline function, adding a check on the maximum value of the class of a priority value as defined by the IOPRIO_CLASS_MAX enum value. Move this function to the kernel side in include/linux/ioprio.h. * Remove the unnecessary "else" after the return statements in task_nice_ioclass(). Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke --- include/linux/ioprio.h | 15 ++++++++++++--- include/uapi/linux/ioprio.h | 19 +++++++++++-------- 2 files changed, 23 insertions(+), 11 deletions(-) diff --git a/include/linux/ioprio.h b/include/linux/ioprio.h index ef9ad4fb245f..9b3a6d8172b4 100644 --- a/include/linux/ioprio.h +++ b/include/linux/ioprio.h @@ -8,6 +8,16 @@ #include +/* + * Check that a priority value has a valid class. + */ +static inline bool ioprio_valid(unsigned short ioprio) +{ + unsigned short class = IOPRIO_PRIO_CLASS(ioprio); + + return class > IOPRIO_CLASS_NONE && class < IOPRIO_CLASS_MAX; +} + /* * if process has set io priority explicitly, use that. if not, convert * the cpu scheduler nice value to an io priority @@ -25,10 +35,9 @@ static inline int task_nice_ioclass(struct task_struct *task) { if (task->policy == SCHED_IDLE) return IOPRIO_CLASS_IDLE; - else if (task_is_realtime(task)) + if (task_is_realtime(task)) return IOPRIO_CLASS_RT; - else - return IOPRIO_CLASS_BE; + return IOPRIO_CLASS_BE; } /* diff --git a/include/uapi/linux/ioprio.h b/include/uapi/linux/ioprio.h index 77b17e08b0da..abc40965aa96 100644 --- a/include/uapi/linux/ioprio.h +++ b/include/uapi/linux/ioprio.h @@ -5,12 +5,15 @@ /* * Gives us 8 prio classes with 13-bits of data for each class */ -#define IOPRIO_CLASS_SHIFT (13) +#define IOPRIO_CLASS_SHIFT 13 +#define IOPRIO_CLASS_MASK 0x07 #define IOPRIO_PRIO_MASK ((1UL << IOPRIO_CLASS_SHIFT) - 1) -#define IOPRIO_PRIO_CLASS(mask) ((mask) >> IOPRIO_CLASS_SHIFT) -#define IOPRIO_PRIO_DATA(mask) ((mask) & IOPRIO_PRIO_MASK) -#define IOPRIO_PRIO_VALUE(class, data) (((class) << IOPRIO_CLASS_SHIFT) | data) +#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_SHIFT) | ((data) & IOPRIO_PRIO_MASK)) /* * These are the io priority groups as implemented by CFQ. RT is the realtime @@ -23,14 +26,14 @@ enum { IOPRIO_CLASS_RT, IOPRIO_CLASS_BE, IOPRIO_CLASS_IDLE, -}; -#define ioprio_valid(mask) (IOPRIO_PRIO_CLASS((mask)) != IOPRIO_CLASS_NONE) + IOPRIO_CLASS_MAX, +}; /* * 8 best effort priority levels are supported */ -#define IOPRIO_BE_NR (8) +#define IOPRIO_BE_NR 8 enum { IOPRIO_WHO_PROCESS = 1, @@ -41,6 +44,6 @@ enum { /* * Fallback BE priority */ -#define IOPRIO_NORM (4) +#define IOPRIO_NORM 4 #endif /* _UAPI_LINUX_IOPRIO_H */