From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-101.freemail.mail.aliyun.com (out30-101.freemail.mail.aliyun.com [115.124.30.101]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4DB7E10F4; Sat, 23 Dec 2023 03:55:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R131e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046049;MF=jefflexu@linux.alibaba.com;NM=1;PH=DS;RN=26;SR=0;TI=SMTPD_---0Vz0J.hE_1703303701; Received: from 30.212.153.241(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0Vz0J.hE_1703303701) by smtp.aliyun-inc.com; Sat, 23 Dec 2023 11:55:04 +0800 Message-ID: Date: Sat, 23 Dec 2023 11:55:00 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] Fix EROFS Kconfig Content-Language: en-US To: David Howells , Gao Xiang Cc: Chao Yu , Yue Hu , Steve French , Matthew Wilcox , Marc Dionne , Paulo Alcantara , Shyam Prasad N , Tom Talpey , Dominique Martinet , Eric Van Hensbergen , Ilya Dryomov , Christian Brauner , linux-cachefs@redhat.com, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-erofs@lists.ozlabs.org, Jeff Layton References: <20231221132400.1601991-5-dhowells@redhat.com> <20231221132400.1601991-1-dhowells@redhat.com> <2265065.1703250126@warthog.procyon.org.uk> From: Jingbo Xu In-Reply-To: <2265065.1703250126@warthog.procyon.org.uk> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi, On 12/22/23 9:02 PM, David Howells wrote: > This needs an additional change (see attached). > > diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig > index 1d318f85232d..1949763e66aa 100644 > --- a/fs/erofs/Kconfig > +++ b/fs/erofs/Kconfig > @@ -114,7 +114,8 @@ config EROFS_FS_ZIP_DEFLATE > > config EROFS_FS_ONDEMAND > bool "EROFS fscache-based on-demand read support" > - depends on CACHEFILES_ONDEMAND && (EROFS_FS=m && FSCACHE || EROFS_FS=y && FSCACHE=y) > + depends on CACHEFILES_ONDEMAND && FSCACHE && \ > + (EROFS_FS=m && NETFS_SUPPORT || EROFS_FS=y && NETFS_SUPPORT=y) > default n > help > This permits EROFS to use fscache-backed data blobs with on-demand > Thanks for the special reminder. I noticed that it has been included in this commit[*] in the dev tree. [*] https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit/?h=netfs-lib&id=7472173cc3baf4a0bd8c803e56c37efdb8388f1c Besides I noticed an issue when trying to configure EROFS_FS_ONDEMAND. The above kconfig indicates that EROFS_FS_ONDEMAND depends on NETFS_SUPPORT, while NETFS_SUPPORT has no prompt in menuconfig and can only be selected by, e.g. fs/ceph/Kconfig: config CEPH_FS select NETFS_SUPPORT IOW EROFS_FS_ONDEMAND will not be prompted and has no way being configured if NETFS_SUPPORT itself is not selected by any other filesystem. I tried to fix this in following way: diff --git a/fs/erofs/Kconfig b/fs/erofs/Kconfig index 1949763e66aa..5b7b71e537f1 100644 --- a/fs/erofs/Kconfig +++ b/fs/erofs/Kconfig @@ -5,6 +5,7 @@ config EROFS_FS depends on BLOCK select FS_IOMAP select LIBCRC32C + select NETFS_SUPPORT if EROFS_FS_ONDEMAND help EROFS (Enhanced Read-Only File System) is a lightweight read-only file system with modern designs (e.g. no buffer heads, inline @@ -114,8 +115,10 @@ config EROFS_FS_ZIP_DEFLATE config EROFS_FS_ONDEMAND bool "EROFS fscache-based on-demand read support" - depends on CACHEFILES_ONDEMAND && FSCACHE && \ - (EROFS_FS=m && NETFS_SUPPORT || EROFS_FS=y && NETFS_SUPPORT=y) + depends on EROFS_FS + select FSCACHE default n help This permits EROFS to use fscache-backed data blobs with on-demand But still the dependency for CACHEFILES_ONDEMAND and CACHEFILES can not be resolved. Though CACHEFILES is not a must during the linking stage as EROFS only calls fscache APIs directly, CACHEFILES is indeed needed to ensure that the EROFS on-demand functionality works at runtime. If we let EROFS_FS_ONDEMAND select CACHEFILES_ONDEMAND, then only CACHEFILES_ONDEMAND will be selected while CACHEFILES can be still N. Maybe EROFS_FS_ONDEMAND needs to selct both CACHEFILES_ONDEMAND and CACHEFILES? Besides if we make EROFS_FS_ONDEMAND depends on CACHEFILES_ONDEMAND, then there will be a recursive dependency loop, as fs/netfs/Kconfig:3:error: recursive dependency detected! fs/netfs/Kconfig:3: symbol NETFS_SUPPORT is selected by EROFS_FS_ONDEMAND fs/erofs/Kconfig:116: symbol EROFS_FS_ONDEMAND depends on CACHEFILES_ONDEMAND fs/cachefiles/Kconfig:30: symbol CACHEFILES_ONDEMAND depends on CACHEFILES fs/cachefiles/Kconfig:3: symbol CACHEFILES depends on NETFS_SUPPORT Hi Xiang, any better idea? -- Thanks, Jingbo