From nobody Tue Apr 7 17:47:43 2026 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 E09F0C4332F for ; Tue, 18 Oct 2022 04:56:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229956AbiJRE4J (ORCPT ); Tue, 18 Oct 2022 00:56:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229718AbiJREzv (ORCPT ); Tue, 18 Oct 2022 00:55:51 -0400 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E416C6525F for ; Mon, 17 Oct 2022 21:55:49 -0700 (PDT) Received: by mail-pj1-x1035.google.com with SMTP id d7-20020a17090a2a4700b0020d268b1f02so16252218pjg.1 for ; Mon, 17 Oct 2022 21:55:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=lPOwozwW566MrhSDQ5Hik/2oBaG/MJdP0TGgYtIKPis=; b=YnRifkaNMN9xeU3dP05q8Ea3BFeTmAimQBXUIgaGkiE2mSiMswcN01xw+OrW2yPYCF OvIXJvFjayfS/j734H+93oHgzpWOVPR33IaJNC/+srLLlOZGNDfcMf0kZlVFSBcKh4MV dADJd8226DEIE85679/r2I8nGKw2AK68/UaEo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=lPOwozwW566MrhSDQ5Hik/2oBaG/MJdP0TGgYtIKPis=; b=3wecTXYPpgSKFeUuItCY7ZprOFecyn/IKah4f7Gay0xQrtP7LlvqgqEqvSVfY0VVh9 UmvgP5lYa5yXFqtyn2OssjlN75eYN6aIN9w1mFtiQLZD4xxNBsSidQ6NdAit8MPxKRLH j7vKTWRjaRmw08ZdWkLwiXZmHPSvFoTNL819bXEqPn58NdtnSuzqTmhVKyaVkdGtNL/w 2P3u2AS4WUl+pZJmTf4Pptc0M6uqKo3inB/GoZmrRuUOSbKyL9b47PRakAtWaYQ1X5DR dExIAtCcX0JRqHMdr/hY/tkHdjXwasHKL2vcyBEp+xT8GGBiGdMvJfq2ZjY9gmTKORG6 owVw== X-Gm-Message-State: ACrzQf3BLra82wJMCNy8WE8ngToogRmKp9HuZpQYWzx1GKrnybKk9vuG gP1Tdo4HaDeChvZA7dGsetIf4g== X-Google-Smtp-Source: AMsMyM68b3LFlOFKZ5ZmhuvTT7t7kmp/l6V3wTu+yDELsOlS3kOPAXwmAmfP+TaiyKDtir3UTdwQrA== X-Received: by 2002:a17:902:c405:b0:181:83e4:490e with SMTP id k5-20020a170902c40500b0018183e4490emr1173860plk.4.1666068949191; Mon, 17 Oct 2022 21:55:49 -0700 (PDT) Received: from tigerii.tok.corp.google.com ([2401:fa00:8f:203:17a9:73b0:c262:eccd]) by smtp.gmail.com with ESMTPSA id p4-20020a170902e74400b0017b69f99321sm7549220plf.219.2022.10.17.21.55.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Oct 2022 21:55:48 -0700 (PDT) From: Sergey Senozhatsky To: Andrew Morton , Minchan Kim Cc: Nitin Gupta , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Sergey Senozhatsky Subject: [PATCHv4 3/9] zram: Factor out WB and non-WB zram read functions Date: Tue, 18 Oct 2022 13:55:27 +0900 Message-Id: <20221018045533.2396670-4-senozhatsky@chromium.org> X-Mailer: git-send-email 2.38.0.413.g74048e4d9e-goog In-Reply-To: <20221018045533.2396670-1-senozhatsky@chromium.org> References: <20221018045533.2396670-1-senozhatsky@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" We will use non-WB variant in ZRAM page recompression path. Signed-off-by: Sergey Senozhatsky --- drivers/block/zram/zram_drv.c | 73 ++++++++++++++++++++++++----------- 1 file changed, 50 insertions(+), 23 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index a8ef3c0c3dae..94c62d7ea818 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1314,8 +1314,30 @@ static void zram_free_page(struct zram *zram, size_t= index) ~(1UL << ZRAM_LOCK | 1UL << ZRAM_UNDER_WB)); } =20 -static int __zram_bvec_read(struct zram *zram, struct page *page, u32 inde= x, - struct bio *bio, bool partial_io) +/* + * Reads a page from the writeback devices. Corresponding ZRAM slot + * should be unlocked. + */ +static int zram_read_from_writeback(struct zram *zram, struct page *page, + u32 index, struct bio *bio, + bool partial_io) +{ + struct bio_vec bvec; + + bvec.bv_page =3D page; + bvec.bv_len =3D PAGE_SIZE; + bvec.bv_offset =3D 0; + return read_from_bdev(zram, &bvec, + zram_get_element(zram, index), + bio, partial_io); +} + +/* + * Reads (decompresses if needed) a page from zspool (zsmalloc). + * Corresponding ZRAM slot should be locked. + */ +static int zram_read_from_zspool(struct zram *zram, struct page *page, + u32 index) { struct zcomp_strm *zstrm; unsigned long handle; @@ -1323,23 +1345,6 @@ static int __zram_bvec_read(struct zram *zram, struc= t page *page, u32 index, void *src, *dst; int ret; =20 - zram_slot_lock(zram, index); - if (zram_test_flag(zram, index, ZRAM_WB)) { - struct bio_vec bvec; - - zram_slot_unlock(zram, index); - /* A null bio means rw_page was used, we must fallback to bio */ - if (!bio) - return -EOPNOTSUPP; - - bvec.bv_page =3D page; - bvec.bv_len =3D PAGE_SIZE; - bvec.bv_offset =3D 0; - return read_from_bdev(zram, &bvec, - zram_get_element(zram, index), - bio, partial_io); - } - handle =3D zram_get_handle(zram, index); if (!handle || zram_test_flag(zram, index, ZRAM_SAME)) { unsigned long value; @@ -1349,7 +1354,6 @@ static int __zram_bvec_read(struct zram *zram, struct= page *page, u32 index, mem =3D kmap_atomic(page); zram_fill_page(mem, PAGE_SIZE, value); kunmap_atomic(mem); - zram_slot_unlock(zram, index); return 0; } =20 @@ -1371,17 +1375,40 @@ static int __zram_bvec_read(struct zram *zram, stru= ct page *page, u32 index, zcomp_stream_put(zram->comps[ZRAM_PRIMARY_ZCOMP]); } zs_unmap_object(zram->mem_pool, handle); - zram_slot_unlock(zram, index); + return ret; +} + +static int __zram_bvec_read(struct zram *zram, struct page *page, u32 inde= x, + struct bio *bio, bool partial_io) +{ + int ret; + + zram_slot_lock(zram, index); + if (!zram_test_flag(zram, index, ZRAM_WB)) { + /* Slot should be locked through out the function call */ + ret =3D zram_read_from_zspool(zram, page, index); + zram_slot_unlock(zram, index); + } else { + /* Slot should be unlocked before the function call */ + zram_slot_unlock(zram, index); + + /* A null bio means rw_page was used, we must fallback to bio */ + if (!bio) + return -EOPNOTSUPP; + + ret =3D zram_read_from_writeback(zram, page, index, bio, + partial_io); + } =20 /* Should NEVER happen. Return bio error if it does. */ - if (WARN_ON(ret)) + if (WARN_ON(ret < 0)) pr_err("Decompression failed! err=3D%d, page=3D%u\n", ret, index); =20 return ret; } =20 static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, - u32 index, int offset, struct bio *bio) + u32 index, int offset, struct bio *bio) { int ret; struct page *page; --=20 2.38.0.413.g74048e4d9e-goog