Re: [PATCH] Fix EROFS Kconfig
From: Jingbo Xu <jefflexu@linux.alibaba.com>
Date: 2023-12-23 03:55:13
Also in:
ceph-devel, linux-cifs, linux-fsdevel, linux-mm, linux-nfs, lkml, v9fs
Subsystem:
erofs file system, filesystems (vfs and infrastructure), the rest · Maintainers:
Gao Xiang, Chao Yu, Alexander Viro, Christian Brauner, Linus Torvalds
Hi, On 12/22/23 9:02 PM, David Howells wrote:
quoted hunk ↗ jump to hunk
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