From patchwork Mon Jul 19 18:39:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 12386595 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,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 922BBC07E9D for ; Mon, 19 Jul 2021 18:41:52 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2DB0961003 for ; Mon, 19 Jul 2021 18:41:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2DB0961003 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CEE208D00F6; Mon, 19 Jul 2021 14:41:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C9DE28D00EC; Mon, 19 Jul 2021 14:41:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B8D768D00F6; Mon, 19 Jul 2021 14:41:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0098.hostedemail.com [216.40.44.98]) by kanga.kvack.org (Postfix) with ESMTP id 924038D00EC for ; Mon, 19 Jul 2021 14:41:52 -0400 (EDT) Received: from smtpin38.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 266F3184C2170 for ; Mon, 19 Jul 2021 18:41:51 +0000 (UTC) X-FDA: 78380206422.38.84293CB Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf23.hostedemail.com (Postfix) with ESMTP id 3545C90000B4 for ; Mon, 19 Jul 2021 18:41:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=zCf/+WAt5kl+bvMl9m+HufeShSb0v0zgYzCTuNOFtYg=; b=Umasx1i81sMBjUJVKN9cC0afgY lhrSYnm7IglhzP/2Y1Mq08lwm8fTV163MBtkXyFylN8FanM9CL60jNeSnyxpfPgf0vqv7yAoA1sec fj8VNTXZBUDZb4pt9y/SK2frJCQ25fL+L4SztXnZdYFxHy7BqO8rkWsOxc2WpLJKX7jgaTQyQa+lY /5M1ByspktSe+/rNftsokYIvN1ilmnpL4Pdudf+Mh6FdFJjedJ8vXAFgrRW7N/LQpS2FA6btVcLtm jKNNubcEfJrU0iIFsiDkVp+2/geTv4wlVrtL1G4AJ3l9EI74WPmzI/t2p+s0iK9oWHS8aXESCFDjH 8lYr8/3g==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1m5YCM-007LUk-PC; Mon, 19 Jul 2021 18:41:17 +0000 From: "Matthew Wilcox (Oracle)" To: linux-fsdevel@vger.kernel.org Cc: "Matthew Wilcox (Oracle)" , linux-mm@kvack.org, linux-block@vger.kernel.org Subject: [PATCH v15 02/17] block: Add bio_for_each_folio_all() Date: Mon, 19 Jul 2021 19:39:46 +0100 Message-Id: <20210719184001.1750630-3-willy@infradead.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210719184001.1750630-1-willy@infradead.org> References: <20210719184001.1750630-1-willy@infradead.org> MIME-Version: 1.0 Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=Umasx1i8; spf=none (imf23.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Stat-Signature: xi4jc6q4dr9peafeu4c9sk43664djnn8 X-Rspamd-Queue-Id: 3545C90000B4 X-Rspamd-Server: rspam01 X-HE-Tag: 1626720110-558452 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: Allow callers to iterate over each folio instead of each page. The bio need not have been constructed using folios originally. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Darrick J. Wong Reported-by: kernel test robot Reported-by: kernel test robot Reported-by: kernel test robot --- Documentation/core-api/kernel-api.rst | 1 + include/linux/bio.h | 53 ++++++++++++++++++++++++++- 2 files changed, 53 insertions(+), 1 deletion(-) diff --git a/Documentation/core-api/kernel-api.rst b/Documentation/core-api/kernel-api.rst index 2a7444e3a4c2..b804605f705e 100644 --- a/Documentation/core-api/kernel-api.rst +++ b/Documentation/core-api/kernel-api.rst @@ -279,6 +279,7 @@ Accounting Framework Block Devices ============= +.. kernel-doc:: include/linux/bio.h .. kernel-doc:: block/blk-core.c :export: diff --git a/include/linux/bio.h b/include/linux/bio.h index ade93e2de6a1..a90a79ad7bd1 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -189,7 +189,7 @@ static inline void bio_advance_iter_single(const struct bio *bio, */ #define bio_for_each_bvec_all(bvl, bio, i) \ for (i = 0, bvl = bio_first_bvec_all(bio); \ - i < (bio)->bi_vcnt; i++, bvl++) \ + i < (bio)->bi_vcnt; i++, bvl++) #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) @@ -314,6 +314,57 @@ static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) return &bio->bi_io_vec[bio->bi_vcnt - 1]; } +/** + * struct folio_iter - State for iterating all folios in a bio. + * @folio: The current folio we're iterating. NULL after the last folio. + * @offset: The byte offset within the current folio. + * @length: The number of bytes in this iteration (will not cross folio + * boundary). + */ +struct folio_iter { + struct folio *folio; + size_t offset; + size_t length; + /* private: for use by the iterator */ + size_t _seg_count; + int _i; +}; + +static inline +void bio_first_folio(struct folio_iter *fi, struct bio *bio, int i) +{ + struct bio_vec *bvec = bio_first_bvec_all(bio) + i; + + fi->folio = page_folio(bvec->bv_page); + fi->offset = bvec->bv_offset + + PAGE_SIZE * (bvec->bv_page - &fi->folio->page); + fi->_seg_count = bvec->bv_len; + fi->length = min(folio_size(fi->folio) - fi->offset, fi->_seg_count); + fi->_i = i; +} + +static inline void bio_next_folio(struct folio_iter *fi, struct bio *bio) +{ + fi->_seg_count -= fi->length; + if (fi->_seg_count) { + fi->folio = folio_next(fi->folio); + fi->offset = 0; + fi->length = min(folio_size(fi->folio), fi->_seg_count); + } else if (fi->_i + 1 < bio->bi_vcnt) { + bio_first_folio(fi, bio, fi->_i + 1); + } else { + fi->folio = NULL; + } +} + +/** + * bio_for_each_folio_all - Iterate over each folio in a bio. + * @fi: struct folio_iter which is updated for each folio. + * @bio: struct bio to iterate over. + */ +#define bio_for_each_folio_all(fi, bio) \ + for (bio_first_folio(&fi, bio, 0); fi.folio; bio_next_folio(&fi, bio)) + enum bip_flags { BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */