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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 4ADA8C76190 for ; Tue, 23 Jul 2019 00:05:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 232F1218BE for ; Tue, 23 Jul 2019 00:05:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="VgLgZhkE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727172AbfGWAFD (ORCPT ); Mon, 22 Jul 2019 20:05:03 -0400 Received: from mail-pl1-f194.google.com ([209.85.214.194]:36179 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727643AbfGWAFA (ORCPT ); Mon, 22 Jul 2019 20:05:00 -0400 Received: by mail-pl1-f194.google.com with SMTP id k8so19850999plt.3 for ; Mon, 22 Jul 2019 17:04:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=message-id:mime-version:content-transfer-encoding:in-reply-to :references:subject:to:cc:from:user-agent:date; bh=uoHZGPhy7AaMBBkhIfbi+3coowHMdF6umFxF94wcksg=; b=VgLgZhkEw8c6bGaz8lCXFux+cen+0GeTncyzKcaz4eOQUkOCuYdm1vzo16ayzWEfFH SHHI1FmMYtbVCh78rrfbsteiwlxOg1o6N1Z3aRpjghlOjBWowZ38LG6oUU0g+HI0YBZv sAbfVWkDIvYzhymezHOXRGayAwrp6CO/wsc6o= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:mime-version :content-transfer-encoding:in-reply-to:references:subject:to:cc:from :user-agent:date; bh=uoHZGPhy7AaMBBkhIfbi+3coowHMdF6umFxF94wcksg=; b=gJQdbsB704qix7OC98RJl+nsvPW7dweT44/EKy+WcOSYpGa5TrRfCgfXnlrdvrdzZf GzRkZQO5Soug1I1KoWdU5kmlNPs+QTmOTNbeir2g8LXSHrt1v06x1WPkHEkBDQkOMbvW uYVO+0y1aZTq18zMDfmuWnLlbcjL7Od4RZVae3PbiCFbYdtXYZVrb8LYYmqdN5IQlHKD /+cOzRgnRC4qiftFmgkfn1BawtMhLg51H2iAjLDlXvDe9PPXHo1i10tYUjBTN4a+9wTn z5/g5NLTW86na6NsZ3lLGVVwcDFO5CuhMI5dUnPT2+lHJpAFe/lqxltTTTYazdJELflG M+2Q== X-Gm-Message-State: APjAAAW+QNAq2bzu74HRP4hKCjmFh5WKHPsmPm22UpB9iDqVyVOsv78B CA8IqbkafaRasv43iMRYFc3MGg== X-Google-Smtp-Source: APXvYqz9Y79Y2hjotjF63w3SFn2Q50huZigbPYsa8KikfgPCyQ+KkptwTSbwCGdTjHMkSd86GOlu5w== X-Received: by 2002:a17:902:1101:: with SMTP id d1mr33344225pla.212.1563840299152; Mon, 22 Jul 2019 17:04:59 -0700 (PDT) Received: from chromium.org ([2620:15c:202:1:fa53:7765:582b:82b9]) by smtp.gmail.com with ESMTPSA id k64sm21699923pge.65.2019.07.22.17.04.58 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Mon, 22 Jul 2019 17:04:58 -0700 (PDT) Message-ID: <5d364f2a.1c69fb81.e3ed.7bfd@mx.google.com> Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable In-Reply-To: <20190722232719.GT30636@minitux> References: <23774.56553.445601.436491@mariner.uk.xensource.com> <20190517210923.202131-3-swboyd@chromium.org> <20190722232719.GT30636@minitux> Subject: Re: [PATCH 2/3] firmware: qcom_scm: Cleanup code in qcom_scm_assign_mem() To: Bjorn Andersson Cc: Andy Gross , linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Ian Jackson , Julien Grall , Avaneesh Kumar Dwivedi From: Stephen Boyd User-Agent: alot/0.8.1 Date: Mon, 22 Jul 2019 17:04:57 -0700 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Quoting Bjorn Andersson (2019-07-22 16:27:19) > On Fri 17 May 14:09 PDT 2019, Stephen Boyd wrote: >=20 > > There are some questionable coding styles in this function. It looks > > quite odd to deref a pointer with array indexing that only uses the > > first element. Also, destroying an input/output variable halfway through > > the function and then overwriting it on success is not clear. It's > > better to use a local variable and the kernel macros to step through > > each bit set in a bitmask and clearly show where outputs are set. > >=20 > > Cc: Ian Jackson > > Cc: Julien Grall > > Cc: Bjorn Andersson > > Cc: Avaneesh Kumar Dwivedi > > Signed-off-by: Stephen Boyd > > --- > > drivers/firmware/qcom_scm.c | 34 ++++++++++++++++------------------ > > include/linux/qcom_scm.h | 9 +++++---- > > 2 files changed, 21 insertions(+), 22 deletions(-) > >=20 > > diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c > > index 0c63495cf269..153f13f72bac 100644 > > --- a/drivers/firmware/qcom_scm.c > > +++ b/drivers/firmware/qcom_scm.c > > @@ -443,7 +443,8 @@ EXPORT_SYMBOL(qcom_scm_set_remote_state); > > */ > > int qcom_scm_assign_mem(phys_addr_t mem_addr, size_t mem_sz, > > unsigned int *srcvm, > > - struct qcom_scm_vmperm *newvm, int dest_cnt) > > + const struct qcom_scm_vmperm *newvm, > > + unsigned int dest_cnt) > > { > > struct qcom_scm_current_perm_info *destvm; > > struct qcom_scm_mem_map_info *mem_to_map; > > @@ -458,11 +459,10 @@ int qcom_scm_assign_mem(phys_addr_t mem_addr, siz= e_t mem_sz, > > int next_vm; > > __le32 *src; > > void *ptr; > > - int ret; > > - int len; > > - int i; > > + int ret, i, b; > > + unsigned long srcvm_bits =3D *srcvm; > > =20 > > - src_sz =3D hweight_long(*srcvm) * sizeof(*src); > > + src_sz =3D hweight_long(srcvm_bits) * sizeof(*src); > > mem_to_map_sz =3D sizeof(*mem_to_map); > > dest_sz =3D dest_cnt * sizeof(*destvm); > > ptr_sz =3D ALIGN(src_sz, SZ_64) + ALIGN(mem_to_map_sz, SZ_64) + > > @@ -475,28 +475,26 @@ int qcom_scm_assign_mem(phys_addr_t mem_addr, siz= e_t mem_sz, > > =20 > > /* Fill source vmid detail */ > > src =3D ptr; > > - len =3D hweight_long(*srcvm); > > - for (i =3D 0; i < len; i++) { > > - src[i] =3D cpu_to_le32(ffs(*srcvm) - 1); > > - *srcvm ^=3D 1 << (ffs(*srcvm) - 1); > > - } > > + i =3D 0; > > + for_each_set_bit(b, &srcvm_bits, sizeof(srcvm_bits)) >=20 > The modem is sad that you only pass 8 here. Changed it to BITS_PER_LONG > to include the modem's permission bit and applied all three patches. >=20 Ah of course. Thanks. BTW, srcvm is an unsigned int, but then we do a bunch of unsigned long operations on them. Maybe the whole API should be changed to be more explicit about the size of the type, i.e. u64?