From patchwork Fri Dec 10 07:36:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 12668799 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 4EDDFC433EF for ; Fri, 10 Dec 2021 07:36:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237953AbhLJHk1 (ORCPT ); Fri, 10 Dec 2021 02:40:27 -0500 Received: from out30-132.freemail.mail.aliyun.com ([115.124.30.132]:58511 "EHLO out30-132.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237797AbhLJHkP (ORCPT ); Fri, 10 Dec 2021 02:40:15 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04407;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=12;SR=0;TI=SMTPD_---0V-8E0RZ_1639121797; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0V-8E0RZ_1639121797) by smtp.aliyun-inc.com(127.0.0.1); Fri, 10 Dec 2021 15:36:38 +0800 From: Jeffle Xu To: dhowells@redhat.com, linux-cachefs@redhat.com, xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org Cc: linux-fsdevel@vger.kernel.org, joseph.qi@linux.alibaba.com, bo.liu@linux.alibaba.com, tao.peng@linux.alibaba.com, gerry@linux.alibaba.com, eguan@linux.alibaba.com, linux-kernel@vger.kernel.org Subject: [RFC 15/19] erofs: implement fscache-based metadata read Date: Fri, 10 Dec 2021 15:36:15 +0800 Message-Id: <20211210073619.21667-16-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20211210073619.21667-1-jefflexu@linux.alibaba.com> References: <20211210073619.21667-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Signed-off-by: Jeffle Xu --- fs/erofs/data.c | 5 +++-- fs/erofs/fscache.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ fs/erofs/internal.h | 3 +++ fs/erofs/super.c | 10 ++++++---- 4 files changed, 57 insertions(+), 6 deletions(-) diff --git a/fs/erofs/data.c b/fs/erofs/data.c index cf71082bd52f..47bd3d0ae94c 100644 --- a/fs/erofs/data.c +++ b/fs/erofs/data.c @@ -12,6 +12,7 @@ struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr) { struct address_space * mapping; + struct erofs_sb_info *sbi; struct page *page; if (sb->s_bdev) { @@ -19,8 +20,8 @@ struct page *erofs_get_meta_page(struct super_block *sb, erofs_blk_t blkaddr) page = read_cache_page_gfp(mapping, blkaddr, mapping_gfp_constraint(mapping, ~__GFP_FS)); } else { - /* TODO: fscache based data path */ - page = ERR_PTR(-EINVAL); + sbi = EROFS_SB(sb); + page = erofs_readpage_from_fscache(sbi->bootstrap, blkaddr); } /* should already be PageUptodate */ diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c index cf550fdedd1e..6fe31d410cbd 100644 --- a/fs/erofs/fscache.c +++ b/fs/erofs/fscache.c @@ -1,5 +1,50 @@ #include "internal.h" +static int erofs_begin_cache_operation(struct netfs_read_request *rreq) +{ + return fscache_begin_read_operation(&rreq->cache_resources, + rreq->netfs_priv); +} + +static void erofs_priv_cleanup(struct address_space *mapping, void *netfs_priv) +{ +} + +const struct netfs_read_request_ops erofs_req_ops = { + .begin_cache_operation = erofs_begin_cache_operation, + .cleanup = erofs_priv_cleanup, +}; + +struct page *erofs_readpage_from_fscache(struct fscache_cookie *cookie, + pgoff_t index) +{ + int ret = -ENOMEM; + struct folio *folio; + struct page *page; + + page = alloc_page(GFP_KERNEL); + if (unlikely(!page)) { + printk("failed to allocate page\n"); + goto err; + } + + page->index = index; + folio = page_folio(page); + + ret = netfs_readpage_demand(folio, &erofs_req_ops, cookie); + if (unlikely(ret || !PageUptodate(page))) { + printk("failed to read from fscache\n"); + goto err_page; + } + + return page; + +err_page: + __free_page(page); +err: + return ERR_PTR(ret); +} + int erofs_fscache_init(struct erofs_sb_info *sbi, char *bootstrap_path) { sbi->volume = fscache_acquire_volume("erofs", NULL, 0); diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 8136ec63a9de..d60d9ffaef2a 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -577,6 +577,9 @@ static inline int z_erofs_load_lzma_config(struct super_block *sb, int erofs_fscache_init(struct erofs_sb_info *sbi, char *bootstrap_path); void erofs_fscache_cleanup(struct erofs_sb_info *sbi); +struct page *erofs_readpage_from_fscache(struct fscache_cookie *cookie, + pgoff_t index); + #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ #endif /* __EROFS_INTERNAL_H */ diff --git a/fs/erofs/super.c b/fs/erofs/super.c index f2a5f4cd53fd..bb68bc81a1a7 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -330,21 +330,23 @@ static int erofs_init_devices(struct super_block *sb, static int erofs_read_superblock(struct super_block *sb) { - struct erofs_sb_info *sbi; + struct erofs_sb_info *sbi = EROFS_SB(sb); struct page *page; struct erofs_super_block *dsb; unsigned int blkszbits; void *data; int ret; - page = read_mapping_page(sb->s_bdev->bd_inode->i_mapping, 0, NULL); + if (sb->s_bdev) + page = read_mapping_page(sb->s_bdev->bd_inode->i_mapping, 0, NULL); + else + page = erofs_readpage_from_fscache(sbi->bootstrap, 0); + if (IS_ERR(page)) { erofs_err(sb, "cannot read erofs superblock"); return PTR_ERR(page); } - sbi = EROFS_SB(sb); - data = kmap(page); dsb = (struct erofs_super_block *)(data + EROFS_SUPER_OFFSET);