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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AAD83C433EF for ; Thu, 16 Dec 2021 21:08:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241837AbhLPVIe (ORCPT ); Thu, 16 Dec 2021 16:08:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53522 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235454AbhLPVHY (ORCPT ); Thu, 16 Dec 2021 16:07:24 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3DA21C061759; Thu, 16 Dec 2021 13:07:24 -0800 (PST) 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=9yx1uM3IgMq95UhqybQy+4eLkKdDKXGRUpPaw12iJ9Q=; b=ju6rjF/d1yjj/3tHRJNwSllSRo dYK94EWF3eLWYVvV2cnhGDp/odpgJzcbaIbJSyvdTL74dS/ZrlHR+NmM+zlaFKfZSaQgWOLvsJcdw 5s+ljgkAD13+hPkG7C2YGTfAtGLyXQYgFDtJFPLrQqAjwd+4QrYBlHWy1AYvTRCr8k/htnO/8S7Oo FLD6BidvJWcDujrldJm3zKn1Nd1UhEqS+dRp7cBdGOMbauUC3lhTcNNjl4i9TdaOXc3aKkt0dSpGA +FpT/ArScSqyN4fzOgmPy0EbimIqX092cTIaKd3c6anX3lOvNhPKlQOgBCz8+aihk0s3P/Yb3HWlC wzGeKREQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mxxyB-00Fx38-1v; Thu, 16 Dec 2021 21:07:19 +0000 From: "Matthew Wilcox (Oracle)" To: "Darrick J. Wong" Cc: "Matthew Wilcox (Oracle)" , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Jens Axboe , Christoph Hellwig Subject: [PATCH v3 02/25] block: Add bio_for_each_folio_all() Date: Thu, 16 Dec 2021 21:06:52 +0000 Message-Id: <20211216210715.3801857-3-willy@infradead.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211216210715.3801857-1-willy@infradead.org> References: <20211216210715.3801857-1-willy@infradead.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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: Jens Axboe Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong --- 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 2e7186805148..7f0cb604b6ab 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 a783cac49978..e3c9e8207f12 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -166,7 +166,7 @@ static inline void bio_advance(struct bio *bio, unsigned int nbytes) */ #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) @@ -260,6 +260,57 @@ 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 */ -- 2.33.0