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 B5BB7C433EF for ; Sun, 2 Jan 2022 08:13:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230090AbiABINb (ORCPT ); Sun, 2 Jan 2022 03:13:31 -0500 Received: from out30-133.freemail.mail.aliyun.com ([115.124.30.133]:38580 "EHLO out30-133.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229505AbiABINa (ORCPT ); Sun, 2 Jan 2022 03:13:30 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R721e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04394;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0V0Z7YBP_1641111204; Received: from e18g06460.et15sqa.tbsite.net(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0V0Z7YBP_1641111204) by smtp.aliyun-inc.com(127.0.0.1); Sun, 02 Jan 2022 16:13:28 +0800 From: Gao Xiang To: linux-erofs@lists.ozlabs.org, Chao Yu , Liu Bo Cc: LKML , Yue Hu , Gao Xiang Subject: [PATCH v3 3/5] erofs: use meta buffers for super operations Date: Sun, 2 Jan 2022 16:13:17 +0800 Message-Id: <20220102081317.109797-1-hsiangkao@linux.alibaba.com> X-Mailer: git-send-email 2.24.4 In-Reply-To: <20220102040017.51352-4-hsiangkao@linux.alibaba.com> References: <20220102040017.51352-4-hsiangkao@linux.alibaba.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Get rid of old erofs_get_meta_page() within super operations by using on-stack meta buffers in order to prepare subpage and folio features. Reviewed-by: Yue Hu Signed-off-by: Gao Xiang --- changes since v2: - add a missing kfree(buffer); - forget to put_metabuf in erofs_load_compr_cfgs; - fotget to put_metabuf in erofs_init_devices. fs/erofs/super.c | 104 ++++++++++++----------------------------------- 1 file changed, 27 insertions(+), 77 deletions(-) diff --git a/fs/erofs/super.c b/fs/erofs/super.c index 0724ad5fd6cf..5c137647fa8a 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -2,6 +2,7 @@ /* * Copyright (C) 2017-2018 HUAWEI, Inc. * https://www.huawei.com/ + * Copyright (C) 2021, Alibaba Cloud */ #include #include @@ -124,80 +125,50 @@ static bool check_layout_compatibility(struct super_block *sb, #ifdef CONFIG_EROFS_FS_ZIP /* read variable-sized metadata, offset will be aligned by 4-byte */ -static void *erofs_read_metadata(struct super_block *sb, struct page **pagep, +static void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf, erofs_off_t *offset, int *lengthp) { - struct page *page = *pagep; u8 *buffer, *ptr; int len, i, cnt; - erofs_blk_t blk; *offset = round_up(*offset, 4); - blk = erofs_blknr(*offset); + ptr = erofs_read_metabuf(buf, sb, erofs_blknr(*offset), EROFS_KMAP); + if (IS_ERR(ptr)) + return ptr; - if (!page || page->index != blk) { - if (page) { - unlock_page(page); - put_page(page); - } - page = erofs_get_meta_page(sb, blk); - if (IS_ERR(page)) - goto err_nullpage; - } - - ptr = kmap(page); len = le16_to_cpu(*(__le16 *)&ptr[erofs_blkoff(*offset)]); if (!len) len = U16_MAX + 1; buffer = kmalloc(len, GFP_KERNEL); - if (!buffer) { - buffer = ERR_PTR(-ENOMEM); - goto out; - } + if (!buffer) + return ERR_PTR(-ENOMEM); *offset += sizeof(__le16); *lengthp = len; for (i = 0; i < len; i += cnt) { cnt = min(EROFS_BLKSIZ - (int)erofs_blkoff(*offset), len - i); - blk = erofs_blknr(*offset); - - if (!page || page->index != blk) { - if (page) { - kunmap(page); - unlock_page(page); - put_page(page); - } - page = erofs_get_meta_page(sb, blk); - if (IS_ERR(page)) { - kfree(buffer); - goto err_nullpage; - } - ptr = kmap(page); + ptr = erofs_read_metabuf(buf, sb, erofs_blknr(*offset), + EROFS_KMAP); + if (IS_ERR(ptr)) { + kfree(buffer); + return ptr; } memcpy(buffer + i, ptr + erofs_blkoff(*offset), cnt); *offset += cnt; } -out: - kunmap(page); - *pagep = page; return buffer; -err_nullpage: - *pagep = NULL; - return page; } static int erofs_load_compr_cfgs(struct super_block *sb, struct erofs_super_block *dsb) { - struct erofs_sb_info *sbi; - struct page *page; + struct erofs_sb_info *sbi = EROFS_SB(sb); + struct erofs_buf buf = __EROFS_BUF_INITIALIZER; unsigned int algs, alg; erofs_off_t offset; - int size, ret; + int size, ret = 0; - sbi = EROFS_SB(sb); sbi->available_compr_algs = le16_to_cpu(dsb->u1.available_compr_algs); - if (sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS) { erofs_err(sb, "try to load compressed fs with unsupported algorithms %x", sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS); @@ -205,20 +176,17 @@ static int erofs_load_compr_cfgs(struct super_block *sb, } offset = EROFS_SUPER_OFFSET + sbi->sb_size; - page = NULL; alg = 0; - ret = 0; - for (algs = sbi->available_compr_algs; algs; algs >>= 1, ++alg) { void *data; if (!(algs & 1)) continue; - data = erofs_read_metadata(sb, &page, &offset, &size); + data = erofs_read_metadata(sb, &buf, &offset, &size); if (IS_ERR(data)) { ret = PTR_ERR(data); - goto err; + break; } switch (alg) { @@ -234,13 +202,9 @@ static int erofs_load_compr_cfgs(struct super_block *sb, } kfree(data); if (ret) - goto err; - } -err: - if (page) { - unlock_page(page); - put_page(page); + break; } + erofs_put_metabuf(&buf); return ret; } #else @@ -261,7 +225,7 @@ static int erofs_init_devices(struct super_block *sb, struct erofs_sb_info *sbi = EROFS_SB(sb); unsigned int ondisk_extradevs; erofs_off_t pos; - struct page *page = NULL; + struct erofs_buf buf = __EROFS_BUF_INITIALIZER; struct erofs_device_info *dif; struct erofs_deviceslot *dis; void *ptr; @@ -285,22 +249,13 @@ static int erofs_init_devices(struct super_block *sb, pos = le16_to_cpu(dsb->devt_slotoff) * EROFS_DEVT_SLOT_SIZE; down_read(&sbi->devs->rwsem); idr_for_each_entry(&sbi->devs->tree, dif, id) { - erofs_blk_t blk = erofs_blknr(pos); struct block_device *bdev; - if (!page || page->index != blk) { - if (page) { - kunmap(page); - unlock_page(page); - put_page(page); - } - - page = erofs_get_meta_page(sb, blk); - if (IS_ERR(page)) { - up_read(&sbi->devs->rwsem); - return PTR_ERR(page); - } - ptr = kmap(page); + ptr = erofs_read_metabuf(&buf, sb, erofs_blknr(pos), + EROFS_KMAP); + if (IS_ERR(ptr)) { + err = PTR_ERR(ptr); + break; } dis = ptr + erofs_blkoff(pos); @@ -309,7 +264,7 @@ static int erofs_init_devices(struct super_block *sb, sb->s_type); if (IS_ERR(bdev)) { err = PTR_ERR(bdev); - goto err_out; + break; } dif->bdev = bdev; dif->dax_dev = fs_dax_get_by_bdev(bdev); @@ -318,13 +273,8 @@ static int erofs_init_devices(struct super_block *sb, sbi->total_blocks += dif->blocks; pos += EROFS_DEVT_SLOT_SIZE; } -err_out: up_read(&sbi->devs->rwsem); - if (page) { - kunmap(page); - unlock_page(page); - put_page(page); - } + erofs_put_metabuf(&buf); return err; } -- 2.24.4