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 X-Spam-Level: X-Spam-Status: No, score=-1.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,URIBL_DBL_ABUSE_MALW autolearn=no 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 4BC91C35247 for ; Tue, 4 Feb 2020 01:37:34 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 028022087E for ; Tue, 4 Feb 2020 01:37:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="1C2hPea9" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 028022087E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A1D756B02CF; Mon, 3 Feb 2020 20:37:33 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 9F4D16B02D1; Mon, 3 Feb 2020 20:37:33 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 90A226B02D2; Mon, 3 Feb 2020 20:37:33 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0165.hostedemail.com [216.40.44.165]) by kanga.kvack.org (Postfix) with ESMTP id 726486B02CF for ; Mon, 3 Feb 2020 20:37:33 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 1CDEE181AEF0B for ; Tue, 4 Feb 2020 01:37:33 +0000 (UTC) X-FDA: 76450732386.24.beam99_24cb0be959d57 X-HE-Tag: beam99_24cb0be959d57 X-Filterd-Recvd-Size: 4091 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf42.hostedemail.com (Postfix) with ESMTP for ; Tue, 4 Feb 2020 01:37:32 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 87FCA20732; Tue, 4 Feb 2020 01:37:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580780252; bh=FEnvN6fXB2mPhtkaGafWB3f+cV4d/5E9F/gWgX0bvAg=; h=Date:From:To:Subject:In-Reply-To:From; b=1C2hPea9gu22kuqAqrLWtPVS0hlweZgaRthhGKPmiDvh46pjVYMe5t/morIxYUwEk TnETeD8Fpo/I3WBh/QDfzN3xoX7Y6qbh1//dYgZgTS3ND5IRu+dTpgJQD3sSl2xSV2 SbSt/ch/0uoWFKPhsf3ZxcKvAWVv9Kzf0NcUXRzA= Date: Mon, 03 Feb 2020 17:37:31 -0800 From: Andrew Morton To: acme@redhat.com, akpm@linux-foundation.org, amritha.nambiar@intel.com, andriy.shevchenko@linux.intel.com, chris@chris-wilson.co.uk, keescook@chromium.org, linux-mm@kvack.org, linux@rasmusvillemoes.dk, mm-commits@vger.kernel.org, mszeredi@redhat.com, steffen.klassert@secunet.com, tobin@kernel.org, torvalds@linux-foundation.org, vineet.gupta1@synopsys.com, will.deacon@arm.com, willemb@google.com, willy@infradead.org, yury.norov@gmail.com Subject: [patch 62/67] lib: make bitmap_parse_user a wrapper on bitmap_parse Message-ID: <20200204013731.tpGyxFNVj%akpm@linux-foundation.org> In-Reply-To: <20200203173311.6269a8be06a05e5a4aa08a93@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Yury Norov Subject: lib: make bitmap_parse_user a wrapper on bitmap_parse Currently we parse user data byte after byte which leads to overcomplicating of parsing algorithm. There are no performance critical users of bitmap_parse_user(), and so we can duplicate user data to kernel buffer and simply call bitmap_parselist(). This rework lets us unify and simplify bitmap_parse() and bitmap_parse_user(), which is done in the following patch. Link: http://lkml.kernel.org/r/20200102043031.30357-5-yury.norov@gmail.com Signed-off-by: Yury Norov Reviewed-by: Andy Shevchenko Cc: Amritha Nambiar Cc: Arnaldo Carvalho de Melo Cc: Chris Wilson Cc: Kees Cook Cc: Matthew Wilcox Cc: Miklos Szeredi Cc: Rasmus Villemoes Cc: Steffen Klassert Cc: "Tobin C . Harding" Cc: Vineet Gupta Cc: Will Deacon Cc: Willem de Bruijn Signed-off-by: Andrew Morton --- lib/bitmap.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) --- a/lib/bitmap.c~lib-make-bitmap_parse_user-a-wrapper-on-bitmap_parse +++ a/lib/bitmap.c @@ -530,22 +530,22 @@ EXPORT_SYMBOL(__bitmap_parse); * then it must be terminated with a \0. * @maskp: pointer to bitmap array that will contain result. * @nmaskbits: size of bitmap, in bits. - * - * Wrapper for __bitmap_parse(), providing it with user buffer. - * - * We cannot have this as an inline function in bitmap.h because it needs - * linux/uaccess.h to get the access_ok() declaration and this causes - * cyclic dependencies. */ int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, unsigned long *maskp, int nmaskbits) { - if (!access_ok(ubuf, ulen)) - return -EFAULT; - return __bitmap_parse((const char __force *)ubuf, - ulen, 1, maskp, nmaskbits); + char *buf; + int ret; + buf = memdup_user_nul(ubuf, ulen); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + ret = bitmap_parse(buf, ulen, maskp, nmaskbits); + + kfree(buf); + return ret; } EXPORT_SYMBOL(bitmap_parse_user); _