fs/xfs/Kconfig

   1 # SPDX-License-Identifier: GPL-2.0-only
   2 config XFS_FS
   3         tristate "XFS filesystem support"
   4         depends on BLOCK
   5         select EXPORTFS
   6         select LIBCRC32C
   7         select FS_IOMAP
   8         help
   9           XFS is a high performance journaling filesystem which originated
  10           on the SGI IRIX platform.  It is completely multi-threaded, can
  11           support large files and large filesystems, extended attributes,
  12           variable block sizes, is extent based, and makes extensive use of
  13           Btrees (directories, extents, free space) to aid both performance
  14           and scalability.
  15
  16           Refer to the documentation at <http://oss.sgi.com/projects/xfs/>
  17           for complete details.  This implementation is on-disk compatible
  18           with the IRIX version of XFS.
  19
  20           To compile this file system support as a module, choose M here: the
  21           module will be called xfs.  Be aware, however, that if the file
  22           system of your root partition is compiled as a module, you'll need
  23           to use an initial ramdisk (initrd) to boot.
  24
  25 config XFS_SUPPORT_V4
  26         bool "Support deprecated V4 (crc=0) format"
  27         depends on XFS_FS
  28         default y
  29         help
  30           The V4 filesystem format lacks certain features that are supported
  31           by the V5 format, such as metadata checksumming, strengthened
  32           metadata verification, and the ability to store timestamps past the
  33           year 2038.  Because of this, the V4 format is deprecated.  All users
  34           should upgrade by backing up their files, reformatting, and restoring
  35           from the backup.
  36
  37           Administrators and users can detect a V4 filesystem by running
  38           xfs_info against a filesystem mountpoint and checking for a string
  39           beginning with "crc=".  If the string "crc=0" is found, the
  40           filesystem is a V4 filesystem.  If no such string is found, please
  41           upgrade xfsprogs to the latest version and try again.
  42
  43           This option will become default N in September 2025.  Support for the
  44           V4 format will be removed entirely in September 2030.  Distributors
  45           can say N here to withdraw support earlier.
  46
  47           To continue supporting the old V4 format (crc=0), say Y.
  48           To close off an attack surface, say N.
  49
  50 config XFS_SUPPORT_ASCII_CI
  51         bool "Support deprecated case-insensitive ascii (ascii-ci=1) format"
  52         depends on XFS_FS
  53         default y
  54         help
  55           The ASCII case insensitivity filesystem feature only works correctly
  56           on systems that have been coerced into using ISO 8859-1, and it does
  57           not work on extended attributes.  The kernel has no visibility into
  58           the locale settings in userspace, so it corrupts UTF-8 names.
  59           Enabling this feature makes XFS vulnerable to mixed case sensitivity
  60           attacks.  Because of this, the feature is deprecated.  All users
  61           should upgrade by backing up their files, reformatting, and restoring
  62           from the backup.
  63
  64           Administrators and users can detect such a filesystem by running
  65           xfs_info against a filesystem mountpoint and checking for a string
  66           beginning with "ascii-ci=".  If the string "ascii-ci=1" is found, the
  67           filesystem is a case-insensitive filesystem.  If no such string is
  68           found, please upgrade xfsprogs to the latest version and try again.
  69
  70           This option will become default N in September 2025.  Support for the
  71           feature will be removed entirely in September 2030.  Distributors
  72           can say N here to withdraw support earlier.
  73
  74           To continue supporting case-insensitivity (ascii-ci=1), say Y.
  75           To close off an attack surface, say N.
  76
  77 config XFS_QUOTA
  78         bool "XFS Quota support"
  79         depends on XFS_FS
  80         select QUOTACTL
  81         help
  82           If you say Y here, you will be able to set limits for disk usage on
  83           a per user and/or a per group basis under XFS.  XFS considers quota
  84           information as filesystem metadata and uses journaling to provide a
  85           higher level guarantee of consistency.  The on-disk data format for
  86           quota is also compatible with the IRIX version of XFS, allowing a
  87           filesystem to be migrated between Linux and IRIX without any need
  88           for conversion.
  89
  90           If unsure, say N.  More comprehensive documentation can be found in
  91           README.quota in the xfsprogs package.  XFS quota can be used either
  92           with or without the generic quota support enabled (CONFIG_QUOTA) -
  93           they are completely independent subsystems.
  94
  95 config XFS_POSIX_ACL
  96         bool "XFS POSIX ACL support"
  97         depends on XFS_FS
  98         select FS_POSIX_ACL
  99         help
 100           POSIX Access Control Lists (ACLs) support permissions for users and
 101           groups beyond the owner/group/world scheme.
 102
 103           If you don't know what Access Control Lists are, say N.
 104
 105 config XFS_RT
 106         bool "XFS Realtime subvolume support"
 107         depends on XFS_FS
 108         help
 109           If you say Y here you will be able to mount and use XFS filesystems
 110           which contain a realtime subvolume.  The realtime subvolume is a
 111           separate area of disk space where only file data is stored.  It was
 112           originally designed to provide deterministic data rates suitable
 113           for media streaming applications, but is also useful as a generic
 114           mechanism for ensuring data and metadata/log I/Os are completely
 115           separated.  Regular file I/Os are isolated to a separate device
 116           from all other requests, and this can be done quite transparently
 117           to applications via the inherit-realtime directory inode flag.
 118
 119           See the xfs man page in section 5 for additional information.
 120
 121           If unsure, say N.
 122
 123 config XFS_DRAIN_INTENTS
 124         bool
 125         select JUMP_LABEL if HAVE_ARCH_JUMP_LABEL
 126
 127 config XFS_ONLINE_SCRUB
 128         bool "XFS online metadata check support"
 129         default n
 130         depends on XFS_FS
 131         depends on TMPFS && SHMEM
 132         select XFS_DRAIN_INTENTS
 133         help
 134           If you say Y here you will be able to check metadata on a
 135           mounted XFS filesystem.  This feature is intended to reduce
 136           filesystem downtime by supplementing xfs_repair.  The key
 137           advantage here is to look for problems proactively so that
 138           they can be dealt with in a controlled manner.
 139
 140           This feature is considered EXPERIMENTAL.  Use with caution!
 141
 142           See the xfs_scrub man page in section 8 for additional information.
 143
 144           If unsure, say N.
 145
 146 config XFS_ONLINE_SCRUB_STATS
 147         bool "XFS online metadata check usage data collection"
 148         default y
 149         depends on XFS_ONLINE_SCRUB
 150         select XFS_DEBUG
 151         help
 152           If you say Y here, the kernel will gather usage data about
 153           the online metadata check subsystem.  This includes the number
 154           of invocations, the outcomes, and the results of repairs, if any.
 155           This may slow down scrub slightly due to the use of high precision
 156           timers and the need to merge per-invocation information into the
 157           filesystem counters.
 158
 159           Usage data are collected in /sys/kernel/debug/xfs/scrub.
 160
 161           If unsure, say N.
 162
 163 config XFS_ONLINE_REPAIR
 164         bool "XFS online metadata repair support"
 165         default n
 166         depends on XFS_FS && XFS_ONLINE_SCRUB
 167         help
 168           If you say Y here you will be able to repair metadata on a
 169           mounted XFS filesystem.  This feature is intended to reduce
 170           filesystem downtime by fixing minor problems before they cause the
 171           filesystem to go down.  However, it requires that the filesystem be
 172           formatted with secondary metadata, such as reverse mappings and inode
 173           parent pointers.
 174
 175           This feature is considered EXPERIMENTAL.  Use with caution!
 176
 177           See the xfs_scrub man page in section 8 for additional information.
 178
 179           If unsure, say N.
 180
 181 config XFS_WARN
 182         bool "XFS Verbose Warnings"
 183         depends on XFS_FS && !XFS_DEBUG
 184         help
 185           Say Y here to get an XFS build with many additional warnings.
 186           It converts ASSERT checks to WARN, so will log any out-of-bounds
 187           conditions that occur that would otherwise be missed. It is much
 188           lighter weight than XFS_DEBUG and does not modify algorithms and will
 189           not cause the kernel to panic on non-fatal errors.
 190
 191           However, similar to XFS_DEBUG, it is only advisable to use this if you
 192           are debugging a particular problem.
 193
 194 config XFS_DEBUG
 195         bool "XFS Debugging support"
 196         depends on XFS_FS
 197         help
 198           Say Y here to get an XFS build with many debugging features,
 199           including ASSERT checks, function wrappers around macros,
 200           and extra sanity-checking functions in various code paths.
 201
 202           Note that the resulting code will be HUGE and SLOW, and probably
 203           not useful unless you are debugging a particular problem.
 204
 205           Say N unless you are an XFS developer, or you play one on TV.
 206
 207 config XFS_ASSERT_FATAL
 208         bool "XFS fatal asserts"
 209         default y
 210         depends on XFS_FS && XFS_DEBUG
 211         help
 212           Set the default DEBUG mode ASSERT failure behavior.
 213
 214           Say Y here to cause DEBUG mode ASSERT failures to result in fatal
 215           errors that BUG() the kernel by default. If you say N, ASSERT failures
 216           result in warnings.
 217
 218           This behavior can be modified at runtime via sysfs.