diff options
| -rw-r--r-- | Documentation/admin-guide/xfs.rst | 23 | ||||
| -rw-r--r-- | fs/xfs/Kconfig | 24 | ||||
| -rw-r--r-- | fs/xfs/xfs_super.c | 13 |
3 files changed, 60 insertions, 0 deletions
diff --git a/Documentation/admin-guide/xfs.rst b/Documentation/admin-guide/xfs.rst index f461d6c33534..a0e271dcaf82 100644 --- a/Documentation/admin-guide/xfs.rst +++ b/Documentation/admin-guide/xfs.rst @@ -210,6 +210,28 @@ When mounting an XFS filesystem, the following options are accepted. inconsistent namespace presentation during or after a failover event. +Deprecation of V4 Format +======================== + +The V4 filesystem format lacks certain features that are supported by +the V5 format, such as metadata checksumming, strengthened metadata +verification, and the ability to store timestamps past the year 2038. +Because of this, the V4 format is deprecated. All users should upgrade +by backing up their files, reformatting, and restoring from the backup. + +Administrators and users can detect a V4 filesystem by running xfs_info +against a filesystem mountpoint and checking for a string containing +"crc=". If no such string is found, please upgrade xfsprogs to the +latest version and try again. + +The deprecation will take place in two parts. Support for mounting V4 +filesystems can now be disabled at kernel build time via Kconfig option. +The option will default to yes until September 2025, at which time it +will be changed to default to no. In September 2030, support will be +removed from the codebase entirely. + +Note: Distributors may choose to withdraw V4 format support earlier than +the dates listed above. Deprecated Mount Options ======================== @@ -217,6 +239,7 @@ Deprecated Mount Options =========================== ================ Name Removal Schedule =========================== ================ +Mounting with V4 filesystem September 2030 =========================== ================ diff --git a/fs/xfs/Kconfig b/fs/xfs/Kconfig index e685299eb3d2..5422227e9e93 100644 --- a/fs/xfs/Kconfig +++ b/fs/xfs/Kconfig @@ -22,6 +22,30 @@ config XFS_FS system of your root partition is compiled as a module, you'll need to use an initial ramdisk (initrd) to boot. +config XFS_SUPPORT_V4 + bool "Support deprecated V4 (crc=0) format" + default y + help + The V4 filesystem format lacks certain features that are supported + by the V5 format, such as metadata checksumming, strengthened + metadata verification, and the ability to store timestamps past the + year 2038. Because of this, the V4 format is deprecated. All users + should upgrade by backing up their files, reformatting, and restoring + from the backup. + + Administrators and users can detect a V4 filesystem by running + xfs_info against a filesystem mountpoint and checking for a string + beginning with "crc=". If the string "crc=0" is found, the + filesystem is a V4 filesystem. If no such string is found, please + upgrade xfsprogs to the latest version and try again. + + This option will become default N in September 2025. Support for the + V4 format will be removed entirely in September 2030. Distributors + can say N here to withdraw support earlier. + + To continue supporting the old V4 format (crc=0), say Y. + To close off an attack surface, say N. + config XFS_QUOTA bool "XFS Quota support" depends on XFS_FS diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index baf5de30eebb..bb1d079b690d 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1450,6 +1450,19 @@ xfs_fc_fill_super( if (error) goto out_free_sb; + /* V4 support is undergoing deprecation. */ + if (!xfs_sb_version_hascrc(&mp->m_sb)) { +#ifdef CONFIG_XFS_SUPPORT_V4 + xfs_warn_once(mp, + "Deprecated V4 format (crc=0) will not be supported after September 2030."); +#else + xfs_warn(mp, + "Deprecated V4 format (crc=0) not supported by kernel."); + error = -EINVAL; + goto out_free_sb; +#endif + } + /* * XFS block mappings use 54 bits to store the logical block offset. * This should suffice to handle the maximum file size that the VFS |