xref: /openbmc/linux/fs/xfs/Kconfig (revision 39f555fb)
1# SPDX-License-Identifier: GPL-2.0-only
2config 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
25config 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
50config 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
77config 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
95config 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
105config 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
123config XFS_DRAIN_INTENTS
124	bool
125	select JUMP_LABEL if HAVE_ARCH_JUMP_LABEL
126
127config 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
146config 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
163config 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
181config 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
194config 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
207config 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.
219