From nobody Mon Apr 6 19:40:36 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 7C00EC433FE for ; Wed, 5 Oct 2022 02:40:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229839AbiJECkt (ORCPT ); Tue, 4 Oct 2022 22:40:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229673AbiJECkb (ORCPT ); Tue, 4 Oct 2022 22:40:31 -0400 Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C8855004B for ; Tue, 4 Oct 2022 19:40:30 -0700 (PDT) Received: by mail-pj1-x102b.google.com with SMTP id b15so6405373pje.1 for ; Tue, 04 Oct 2022 19:40:30 -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; bh=+8HyA4g1G7SzaN6nxygfOgRk8GE0piuM7BVZrp+fZZ0=; b=iJZoZ988DbLfqFyS85LiqYK0iD0Jl5QFkdRZH/o20Tn4yzm1XYNlW1NvR8vRf6IVWb pRjXWrj+frDOYasSYToNs0l/W03Wt0QpzcH/Ya0mtEBpV4j42YFvVLcLyWZpMf9YkFJ7 Zs6v0x3YQ6L/TCAVKMbkXph43Miyvc2knSfbA= 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; bh=+8HyA4g1G7SzaN6nxygfOgRk8GE0piuM7BVZrp+fZZ0=; b=jH2sHrT4G6QLkkcj7/VBcqiQxg3UUyLHGnm8idAND0faO1FS/Xo0xNEK1Pt02W+Pmi XbteRU5T5Lr0ajsEjjbZOeFqQvYu1593nBYcs9DHpuOswtutg2yGI8meOltTtJ08MviR rgLFbA4lbmUT1/wF2WCeSWOkdIsDVEFBPqJYeA9Qu/kk7mat1JH3atJXxocUkEFFk9bt WnKUEOFt5kle442YpTCuVNeJObQMtfgnjz0/8OqnrTrutRKYsaREF9EewR7doaSliAl/ 5jkL/wa77LnqgUVPKDgdI47TYNQDhssZKYPi5aT3dBw5LHnjjOL1109UGkIIE8gtjplm KRSA== X-Gm-Message-State: ACrzQf1t6vGNniPG90KC4MKfLTrSR2FWrtvCzyqBTn7OJ6owISVm+8n5 JyycMMjjMUgQEBAq5ha2LdF5Tw== X-Google-Smtp-Source: AMsMyM5PtNm+kNj458oT3nacLJb/Pc90yrx3l6fXrSCv72h7b3aeffHIBEIPGYclwk6h6GPHs0r6AA== X-Received: by 2002:a17:902:8541:b0:17f:6b27:7a75 with SMTP id d1-20020a170902854100b0017f6b277a75mr8912286plo.65.1664937629863; Tue, 04 Oct 2022 19:40:29 -0700 (PDT) Received: from tigerii.tok.corp.google.com ([2401:fa00:8f:203:a9d9:6396:ee12:8be8]) by smtp.gmail.com with ESMTPSA id a14-20020aa794ae000000b00561e010a309sm1673579pfl.19.2022.10.04.19.40.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 04 Oct 2022 19:40:29 -0700 (PDT) From: Sergey Senozhatsky To: Minchan Kim , Andrew Morton Cc: Nitin Gupta , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Sergey Senozhatsky Subject: [PATCHv2 3/8] zram: Factor out WB and non-WB zram read functions Date: Wed, 5 Oct 2022 11:40:09 +0900 Message-Id: <20221005024014.22914-4-senozhatsky@chromium.org> X-Mailer: git-send-email 2.38.0.rc1.362.ged0d419d3c-goog In-Reply-To: <20221005024014.22914-1-senozhatsky@chromium.org> References: <20221005024014.22914-1-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 | 70 ++++++++++++++++++++++++----------- 1 file changed, 48 insertions(+), 22 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index a8ef3c0c3dae..9ec60deeb186 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1314,8 +1314,34 @@ 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; + + /* 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); +} + +/* + * 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 +1349,6 @@ 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 +1358,6 @@ 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 @@ -1371,7 +1379,25 @@ static int __zram_bvec_read(struct zram *zram, struc= t 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); + 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)) @@ -1381,7 +1407,7 @@ static int __zram_bvec_read(struct zram *zram, struct= page *page, u32 index, } =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.rc1.362.ged0d419d3c-goog