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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47BABC001DE for ; Sun, 30 Jul 2023 11:01:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 507E38D0006; Sun, 30 Jul 2023 07:01:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4B8D48D0001; Sun, 30 Jul 2023 07:01:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3A6DA8D0006; Sun, 30 Jul 2023 07:01:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 2B3D58D0001 for ; Sun, 30 Jul 2023 07:01:40 -0400 (EDT) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 609AB1609B7 for ; Sun, 30 Jul 2023 11:01:39 +0000 (UTC) X-FDA: 81067987518.30.C3CDB5E Received: from out-64.mta0.migadu.com (out-64.mta0.migadu.com [91.218.175.64]) by imf01.hostedemail.com (Postfix) with ESMTP id 6CB554000B for ; Sun, 30 Jul 2023 11:01:37 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=XpXFu6Wx; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf01.hostedemail.com: domain of yanjun.zhu@linux.dev designates 91.218.175.64 as permitted sender) smtp.mailfrom=yanjun.zhu@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1690714897; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=YDqItS6TsBITc0ogQeiO9zs2cfijso9HiN6zsa9jo50=; b=sarDFepK14XYwYDAWI/lnS6iglVXYzK1IYSOliClMpryE1PVSPNNcbql0+EWm4mPoH8D5g JtluGoh4h+dZ/ku//3SpAmYtX+QoHwI4+OrsLZWKFq5gSMOcWQFlOkb3F0eEnsjo/r/KVQ CaLwM3KYmBuQoxsxDtmdHEGeUUG6Gog= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=XpXFu6Wx; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf01.hostedemail.com: domain of yanjun.zhu@linux.dev designates 91.218.175.64 as permitted sender) smtp.mailfrom=yanjun.zhu@linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1690714897; a=rsa-sha256; cv=none; b=rnrg5DnBtuGQI4Gs3DlI7hQN4ay4BtDZZvsQeFQQirdcFwzdjj7APqgwzc5trLedpQTMXo 2OhlQqX38JwLwhLjyEdtGW+Mdsa8ZCEAxVdwpo35UbXBZGPDpXgQ2HGfpeXvYjNAb+zzoL KSlrGrJ/BrDdk21ZvIWzQZIkPHdwN/Q= Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1690714895; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=YDqItS6TsBITc0ogQeiO9zs2cfijso9HiN6zsa9jo50=; b=XpXFu6WxU3V13MvRIEnz/7Ji7DORifqqz168/epr0ILzyigpBFV+A4z4oGIVSkBtUeOFgh diNqH0zw0JE5/uCXG3B6N+tvcHXMpKZsZ6s0eKFzsZ+X7f+mOxmtYIXl0uv700u7SMTX1R uLBVb66nh3KObdbTdSfDQ/9rS/J3C2k= Date: Sun, 30 Jul 2023 19:01:26 +0800 MIME-Version: 1.0 Subject: Re: [PATCH 03/13] scatterlist: Add sg_set_folio() To: "Matthew Wilcox (Oracle)" , linux-mm@kvack.org, Andrew Morton Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org References: <20230621164557.3510324-1-willy@infradead.org> <20230621164557.3510324-4-willy@infradead.org> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Zhu Yanjun In-Reply-To: <20230621164557.3510324-4-willy@infradead.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 6CB554000B X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: siijrahiyfibphmimw6ykx9uefmoqewn X-HE-Tag: 1690714897-369253 X-HE-Meta: U2FsdGVkX18Oz1oNeMyyJ9HjV2G2WeJ3Xe7bhmitl3V2nGp3d/Y6bcEEXCG2mf3KMJIvg6xKRHXQneKMXkGpjzq7xe6ugnpVtlMA31hyZZTYejJpWdk3fOvGPG2dkS3UCQEYPNWh6Araq5dXY9sJu8GSCodYNPNaid8b6Teu7mfiPcNsWIS20iU911I+9FKK+ieM8bLMcmX/fFjkYbNmxVXdNGz+f2H1GsI9YygP/otXm+kqyZjhmKX2CpGF5tIGp5X67bZMevf2ORPtSsAEgM9xPVXvb+lsQSguUl1u2xMHBG6i9OlJLkcnT4ys9hfbJ7dSzCCrmeUM9au6zdDO4gQlzIGfSyDWAKmxYM3iVm9TAW5igpZlzvQOgWvCZwC3FlPaF2XkvF30bX+BHGuMRxDJnNss4Lwln7Jvbeltgm4+39eZyliXuMd2uDhs9xoTxOFCl5AWQrT3i1tfMHcYvqpPPB8FJZRJWlM7q7v/XTY2bG74tb0q83qed3oHzdMgs4Peu3mnZo00C1Woe0LNgFs/GwWgfkf+addDqOYj7z+HBASkGvPNhIxM7wgcPyoI1FdxhNghaPcsZVzEK1gtqwIDtCYCZozOHmTRvLAgN08Nt1oQt575qbAJcC41cR3d4UPDBdr/EAuFt1bVtH8WYJD4RRjS8QuUboc/kT7NfLRgL40aEg3EM3pIdlfnCuX8mOQUBYvxbcs1MvVi7gWlVl7WA6wbYhVD2D9NAdq/Lf0xCLIc9S20F10eDYUwX8ePYgz+dZIZrEUu1LFFKkSVimLDpSBV/pW2LiqKG6QcAWQL/3zYHaoGEuSmbp7wH2YLNOCqWNCzm57EQVlt4KtcT5RjBv2e3qKUxHG4kfdsAG8foz5ZaXiRjw47yrnF/Ejgy6vrZGmXu7Cbx3AkKc56frIe44zr8btXnaTDUHzWSU4N0ySjHYiC2OWirVshtFikie+x3xyJfnybncEGxmn zZc8ji/H NqKMLJ+7pobFDwIV7/dbv6806Goup9jUSgvLpwzrySAPE/SJTYDVyEqAy+GFc7VwtyFYooauv6DdcSytmS7BnGbY+tOHs6qDLj4exR7HddlSJLlboEdFfIo2fml/QkGaXexKmdX30YDqOPt0ahJ1sRsA1lMD4HQMQX1adbz6h87GEwE9GdtRVPgd3oI6EVu2PbCfXmclTwaDNR9zcUuNIA77X2R2zPBWjQzaGEBV2iPuad8/9y9O6toYktYZt3xuyG0dE 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: 在 2023/6/22 0:45, Matthew Wilcox (Oracle) 写道: > This wrapper for sg_set_page() lets drivers add folios to a scatterlist > more easily. We could, perhaps, do better by using a different page > in the folio if offset is larger than UINT_MAX, but let's hope we get > a better data structure than this before we need to care about such > large folios. > > Signed-off-by: Matthew Wilcox (Oracle) > --- > include/linux/scatterlist.h | 24 ++++++++++++++++++++++++ > 1 file changed, 24 insertions(+) > > diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h > index ec46d8e8e49d..77df3d7b18a6 100644 > --- a/include/linux/scatterlist.h > +++ b/include/linux/scatterlist.h > @@ -141,6 +141,30 @@ static inline void sg_set_page(struct scatterlist *sg, struct page *page, > sg->length = len; > } > > +/** > + * sg_set_folio - Set sg entry to point at given folio > + * @sg: SG entry > + * @folio: The folio > + * @len: Length of data > + * @offset: Offset into folio > + * > + * Description: > + * Use this function to set an sg entry pointing at a folio, never assign > + * the folio directly. We encode sg table information in the lower bits > + * of the folio pointer. See sg_page() for looking up the page belonging > + * to an sg entry. > + * > + **/ > +static inline void sg_set_folio(struct scatterlist *sg, struct folio *folio, > + size_t len, size_t offset) > +{ > + WARN_ON_ONCE(len > UINT_MAX); > + WARN_ON_ONCE(offset > UINT_MAX); > + sg_assign_page(sg, &folio->page); > + sg->offset = offset; > + sg->length = len; > +} > + https://elixir.bootlin.com/linux/latest/source/lib/scatterlist.c#L451 Does the following function have folio version? " int sg_alloc_append_table_from_pages(struct sg_append_table *sgt_append, struct page **pages, unsigned int n_pages, unsigned int offset, unsigned long size, unsigned int max_segment, unsigned int left_pages, gfp_t gfp_mask) " Thanks a lot. Zhu Yanjun > static inline struct page *sg_page(struct scatterlist *sg) > { > #ifdef CONFIG_DEBUG_SG