From mboxrd@z Thu Jan 1 00:00:00 1970 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 7ADD3C433FE for ; Thu, 7 Apr 2022 02:50:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239594AbiDGCw2 (ORCPT ); Wed, 6 Apr 2022 22:52:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239540AbiDGCwX (ORCPT ); Wed, 6 Apr 2022 22:52:23 -0400 Received: from out199-1.us.a.mail.aliyun.com (out199-1.us.a.mail.aliyun.com [47.90.199.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86D1611DD35; Wed, 6 Apr 2022 19:50:24 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01424;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=19;SR=0;TI=SMTPD_---0V9Onnyg_1649299816; Received: from B-P7TQMD6M-0146.local(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0V9Onnyg_1649299816) by smtp.aliyun-inc.com(127.0.0.1); Thu, 07 Apr 2022 10:50:18 +0800 Date: Thu, 7 Apr 2022 10:50:16 +0800 From: Gao Xiang To: Jeffle Xu Cc: dhowells@redhat.com, linux-cachefs@redhat.com, xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org, torvalds@linux-foundation.org, gregkh@linuxfoundation.org, willy@infradead.org, 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, luodaowen.backend@bytedance.com, tianzichen@kuaishou.com, fannaihao@baidu.com Subject: Re: [PATCH v8 10/20] erofs: register fscache volume Message-ID: Mail-Followup-To: Jeffle Xu , dhowells@redhat.com, linux-cachefs@redhat.com, xiang@kernel.org, chao@kernel.org, linux-erofs@lists.ozlabs.org, torvalds@linux-foundation.org, gregkh@linuxfoundation.org, willy@infradead.org, 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, luodaowen.backend@bytedance.com, tianzichen@kuaishou.com, fannaihao@baidu.com References: <20220406075612.60298-1-jefflexu@linux.alibaba.com> <20220406075612.60298-11-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20220406075612.60298-11-jefflexu@linux.alibaba.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 06, 2022 at 03:56:02PM +0800, Jeffle Xu wrote: > A new fscache based mode is going to be introduced for erofs, in which > case on-demand read semantics is implemented through fscache. > > As the first step, register fscache volume for each erofs filesystem. > That means, data blobs can not be shared among erofs filesystems. In the > following iteration, we are going to introduce the domain semantics, in > which case several erofs filesystems can belong to one domain, and data > blobs can be shared among these erofs filesystems of one domain. > > Signed-off-by: Jeffle Xu Reviewed-by: Gao Xiang Thanks, Gao Xiang > --- > fs/erofs/Kconfig | 10 ++++++++++ > fs/erofs/Makefile | 1 + > fs/erofs/fscache.c | 37 +++++++++++++++++++++++++++++++++++++ > fs/erofs/internal.h | 13 +++++++++++++ > fs/erofs/super.c | 7 +++++++ > 5 files changed, 68 insertions(+) > create mode 100644 fs/erofs/fscache.c > > diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig > index f57255ab88ed..3d05265e3e8e 100644 > --- a/fs/erofs/Kconfig > +++ b/fs/erofs/Kconfig > @@ -98,3 +98,13 @@ config EROFS_FS_ZIP_LZMA > systems will be readable without selecting this option. > > If unsure, say N. > + > +config EROFS_FS_ONDEMAND > + bool "EROFS fscache-based ondemand-read" > + depends on CACHEFILES_ONDEMAND && (EROFS_FS=m && FSCACHE || EROFS_FS=y && FSCACHE=y) > + default n > + help > + EROFS is mounted from data blobs and on-demand read semantics is > + implemented through fscache. > + > + If unsure, say N. > diff --git a/fs/erofs/Makefile b/fs/erofs/Makefile > index 8a3317e38e5a..99bbc597a3e9 100644 > --- a/fs/erofs/Makefile > +++ b/fs/erofs/Makefile > @@ -5,3 +5,4 @@ erofs-objs := super.o inode.o data.o namei.o dir.o utils.o pcpubuf.o sysfs.o > erofs-$(CONFIG_EROFS_FS_XATTR) += xattr.o > erofs-$(CONFIG_EROFS_FS_ZIP) += decompressor.o zmap.o zdata.o > erofs-$(CONFIG_EROFS_FS_ZIP_LZMA) += decompressor_lzma.o > +erofs-$(CONFIG_EROFS_FS_ONDEMAND) += fscache.o > diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c > new file mode 100644 > index 000000000000..7a6d0239ebb1 > --- /dev/null > +++ b/fs/erofs/fscache.c > @@ -0,0 +1,37 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (C) 2022, Alibaba Cloud > + */ > +#include > +#include "internal.h" > + > +int erofs_fscache_register_fs(struct super_block *sb) > +{ > + struct erofs_sb_info *sbi = EROFS_SB(sb); > + struct fscache_volume *volume; > + char *name; > + int ret = 0; > + > + name = kasprintf(GFP_KERNEL, "erofs,%s", sbi->opt.fsid); > + if (!name) > + return -ENOMEM; > + > + volume = fscache_acquire_volume(name, NULL, NULL, 0); > + if (IS_ERR_OR_NULL(volume)) { > + erofs_err(sb, "failed to register volume for %s", name); > + ret = volume ? PTR_ERR(volume) : -EOPNOTSUPP; > + volume = NULL; > + } > + > + sbi->volume = volume; > + kfree(name); > + return ret; > +} > + > +void erofs_fscache_unregister_fs(struct super_block *sb) > +{ > + struct erofs_sb_info *sbi = EROFS_SB(sb); > + > + fscache_relinquish_volume(sbi->volume, NULL, false); > + sbi->volume = NULL; > +} > diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h > index 05a97533b1e9..952a2f483f94 100644 > --- a/fs/erofs/internal.h > +++ b/fs/erofs/internal.h > @@ -74,6 +74,7 @@ struct erofs_mount_opts { > unsigned int max_sync_decompress_pages; > #endif > unsigned int mount_opt; > + char *fsid; > }; > > struct erofs_dev_context { > @@ -146,6 +147,9 @@ struct erofs_sb_info { > /* sysfs support */ > struct kobject s_kobj; /* /sys/fs/erofs/ */ > struct completion s_kobj_unregister; > + > + /* fscache support */ > + struct fscache_volume *volume; > }; > > #define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info) > @@ -618,6 +622,15 @@ static inline int z_erofs_load_lzma_config(struct super_block *sb, > } > #endif /* !CONFIG_EROFS_FS_ZIP */ > > +/* fscache.c */ > +#ifdef CONFIG_EROFS_FS_ONDEMAND > +int erofs_fscache_register_fs(struct super_block *sb); > +void erofs_fscache_unregister_fs(struct super_block *sb); > +#else > +static inline int erofs_fscache_register_fs(struct super_block *sb) { return 0; } > +static inline void erofs_fscache_unregister_fs(struct super_block *sb) {} > +#endif > + > #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ > > #endif /* __EROFS_INTERNAL_H */ > diff --git a/fs/erofs/super.c b/fs/erofs/super.c > index 0c4b41130c2f..6590ed1b7d3b 100644 > --- a/fs/erofs/super.c > +++ b/fs/erofs/super.c > @@ -601,6 +601,12 @@ static int erofs_fc_fill_super(struct super_block *sb, struct fs_context *fc) > sbi->devs = ctx->devs; > ctx->devs = NULL; > > + if (erofs_is_fscache_mode(sb)) { > + err = erofs_fscache_register_fs(sb); > + if (err) > + return err; > + } > + > err = erofs_read_superblock(sb); > if (err) > return err; > @@ -757,6 +763,7 @@ static void erofs_kill_sb(struct super_block *sb) > > erofs_free_dev_context(sbi->devs); > fs_put_dax(sbi->dax_dev); > + erofs_fscache_unregister_fs(sb); > kfree(sbi); > sb->s_fs_info = NULL; > } > -- > 2.27.0