1# SPDX-License-Identifier: GPL-2.0
  2#
  3# Block layer core configuration
  4#
  5menuconfig BLOCK
  6       bool "Enable the block layer" if EXPERT
  7       default y
  8       select FS_IOMAP
  9       select SBITMAP
 10       help
 11	 Provide block layer support for the kernel.
 12
 13	 Disable this option to remove the block layer support from the
 14	 kernel. This may be useful for embedded devices.
 15
 16	 If this option is disabled:
 17
 18	   - block device files will become unusable
 19	   - some filesystems (such as ext3) will become unavailable.
 20
 21	 Also, SCSI character devices and USB storage will be disabled since
 22	 they make use of various block layer definitions and facilities.
 23
 24	 Say Y here unless you know you really don't want to mount disks and
 25	 suchlike.
 26
 27if BLOCK
 28
 29config BLOCK_LEGACY_AUTOLOAD
 30	bool "Legacy autoloading support"
 
 31	default y
 32	help
 33	  Enable loading modules and creating block device instances based on
 34	  accesses through their device special file.  This is a historic Linux
 35	  feature and makes no sense in a udev world where device files are
 36	  created on demand, but scripts that manually create device nodes and
 37	  then call losetup might rely on this behavior.
 38
 39config BLK_RQ_ALLOC_TIME
 40	bool
 
 
 
 
 
 
 
 
 
 
 41
 42config BLK_CGROUP_RWSTAT
 43	bool
 44
 45config BLK_CGROUP_PUNT_BIO
 46	bool
 47
 48config BLK_DEV_BSG_COMMON
 49	tristate
 
 
 
 
 50
 51config BLK_ICQ
 52	bool
 
 
 
 
 
 
 
 
 53
 54config BLK_DEV_BSGLIB
 55	bool "Block layer SG support v4 helper lib"
 56	select BLK_DEV_BSG_COMMON
 
 57	help
 58	  Subsystems will normally enable this if needed. Users will not
 59	  normally need to manually enable this.
 60
 61	  If unsure, say N.
 62
 63config BLK_DEV_INTEGRITY
 64	bool "Block layer data integrity support"
 65	help
 
 66	Some storage devices allow extra information to be
 67	stored/retrieved to help protect the data.  The block layer
 68	data integrity option provides hooks which can be used by
 69	filesystems to ensure better data integrity.
 70
 71	Say yes here if you have a storage device that provides the
 72	T10/SCSI Data Integrity Field or the T13/ATA External Path
 73	Protection.  If in doubt, say N.
 74
 75config BLK_DEV_INTEGRITY_T10
 76	tristate
 77	depends on BLK_DEV_INTEGRITY
 78	select CRC_T10DIF
 79	select CRC64_ROCKSOFT
 80
 81config BLK_DEV_WRITE_MOUNTED
 82	bool "Allow writing to mounted block devices"
 83	default y
 84	help
 85	When a block device is mounted, writing to its buffer cache is very
 86	likely going to cause filesystem corruption. It is also rather easy to
 87	crash the kernel in this way since the filesystem has no practical way
 88	of detecting these writes to buffer cache and verifying its metadata
 89	integrity. However there are some setups that need this capability
 90	like running fsck on read-only mounted root device, modifying some
 91	features on mounted ext4 filesystem, and similar. If you say N, the
 92	kernel will prevent processes from writing to block devices that are
 93	mounted by filesystems which provides some more protection from runaway
 94	privileged processes and generally makes it much harder to crash
 95	filesystem drivers. Note however that this does not prevent
 96	underlying device(s) from being modified by other means, e.g. by
 97	directly submitting SCSI commands or through access to lower layers of
 98	storage stack. If in doubt, say Y. The configuration can be overridden
 99	with the bdev_allow_write_mounted boot option.
100
101config BLK_DEV_ZONED
102	bool "Zoned block device support"
103	select MQ_IOSCHED_DEADLINE
104	help
105	Block layer zoned block device support. This option enables
106	support for ZAC/ZBC/ZNS host-managed and host-aware zoned block
107	devices.
108
109	Say yes here if you have a ZAC, ZBC, or ZNS storage device.
110
111config BLK_DEV_THROTTLING
112	bool "Block layer bio throttling support"
113	depends on BLK_CGROUP
114	select BLK_CGROUP_RWSTAT
115	help
116	Block layer bio throttling support. It can be used to limit
117	the IO rate to a device. IO rate policies are per cgroup and
118	one needs to mount and use blkio cgroup controller for creating
119	cgroups and specifying per device IO rate policies.
120
121	See Documentation/admin-guide/cgroup-v1/blkio-controller.rst for more information.
122
123config BLK_DEV_THROTTLING_LOW
124	bool "Block throttling .low limit interface support (EXPERIMENTAL)"
125	depends on BLK_DEV_THROTTLING
126	help
127	Add .low limit interface for block throttling. The low limit is a best
128	effort limit to prioritize cgroups. Depending on the setting, the limit
129	can be used to protect cgroups in terms of bandwidth/iops and better
130	utilize disk resource.
131
132	Note, this is an experimental interface and could be changed someday.
 
 
 
 
 
 
 
133
134config BLK_WBT
135	bool "Enable support for block device writeback throttling"
136	help
137	Enabling this option enables the block layer to throttle buffered
138	background writeback from the VM, making it more smooth and having
139	less impact on foreground operations. The throttling is done
140	dynamically on an algorithm loosely based on CoDel, factoring in
141	the realtime performance of the disk.
142
143config BLK_WBT_MQ
144	bool "Enable writeback throttling by default"
145	default y
146	depends on BLK_WBT
147	help
148	Enable writeback throttling by default for request-based block devices.
149
150config BLK_CGROUP_IOLATENCY
151	bool "Enable support for latency based cgroup IO protection"
152	depends on BLK_CGROUP
153	help
154	Enabling this option enables the .latency interface for IO throttling.
155	The IO controller will attempt to maintain average IO latencies below
156	the configured latency target, throttling anybody with a higher latency
157	target than the victimized group.
158
159	Note, this is an experimental interface and could be changed someday.
160
161config BLK_CGROUP_FC_APPID
162	bool "Enable support to track FC I/O Traffic across cgroup applications"
163	depends on BLK_CGROUP && NVME_FC
164	help
165	  Enabling this option enables the support to track FC I/O traffic across
166	  cgroup applications. It enables the Fabric and the storage targets to
167	  identify, monitor, and handle FC traffic based on VM tags by inserting
168	  application specific identification into the FC frame.
169
170config BLK_CGROUP_IOCOST
171	bool "Enable support for cost model based cgroup IO controller"
172	depends on BLK_CGROUP
173	select BLK_RQ_ALLOC_TIME
174	help
175	Enabling this option enables the .weight interface for cost
176	model based proportional IO control.  The IO controller
177	distributes IO capacity between different groups based on
178	their share of the overall weight distribution.
179
180config BLK_CGROUP_IOPRIO
181	bool "Cgroup I/O controller for assigning an I/O priority class"
182	depends on BLK_CGROUP
183	help
184	Enable the .prio interface for assigning an I/O priority class to
185	requests. The I/O priority class affects the order in which an I/O
186	scheduler and block devices process requests. Only some I/O schedulers
187	and some block devices support I/O priorities.
188
189config BLK_DEBUG_FS
190	bool "Block layer debugging information in debugfs"
191	default y
192	depends on DEBUG_FS
193	help
194	Include block layer debugging information in debugfs. This information
195	is mostly useful for kernel developers, but it doesn't incur any cost
196	at runtime.
197
198	Unless you are building a kernel for a tiny system, you should
199	say Y here.
200
201config BLK_DEBUG_FS_ZONED
202       bool
203       default BLK_DEBUG_FS && BLK_DEV_ZONED
204
205config BLK_SED_OPAL
206	bool "Logic for interfacing with Opal enabled SEDs"
207	depends on KEYS
208	select PSERIES_PLPKS if PPC_PSERIES
209	select PSERIES_PLPKS_SED if PPC_PSERIES
210	help
211	Builds Logic for interfacing with Opal enabled controllers.
212	Enabling this option enables users to setup/unlock/lock
213	Locking ranges for SED devices using the Opal protocol.
214
215config BLK_INLINE_ENCRYPTION
216	bool "Enable inline encryption support in block layer"
217	help
218	  Build the blk-crypto subsystem. Enabling this lets the
219	  block layer handle encryption, so users can take
220	  advantage of inline encryption hardware if present.
221
222config BLK_INLINE_ENCRYPTION_FALLBACK
223	bool "Enable crypto API fallback for blk-crypto"
224	depends on BLK_INLINE_ENCRYPTION
225	select CRYPTO
226	select CRYPTO_SKCIPHER
227	help
228	  Enabling this lets the block layer handle inline encryption
229	  by falling back to the kernel crypto API when inline
230	  encryption hardware is not present.
231
232source "block/partitions/Kconfig"
233
234config BLK_MQ_PCI
235	def_bool PCI
236
237config BLK_MQ_VIRTIO
238	bool
239	depends on VIRTIO
240	default y
241
242config BLK_PM
243	def_bool PM
244
245# do not use in new code
246config BLOCK_HOLDER_DEPRECATED
247	bool
248
249config BLK_MQ_STACKING
250	bool
 
 
251
252source "block/Kconfig.iosched"
253
254endif # BLOCK

 
  1#
  2# Block layer core configuration
  3#
  4menuconfig BLOCK
  5       bool "Enable the block layer" if EXPERT
  6       default y
 
 
  7       help
  8	 Provide block layer support for the kernel.
  9
 10	 Disable this option to remove the block layer support from the
 11	 kernel. This may be useful for embedded devices.
 12
 13	 If this option is disabled:
 14
 15	   - block device files will become unusable
 16	   - some filesystems (such as ext3) will become unavailable.
 17
 18	 Also, SCSI character devices and USB storage will be disabled since
 19	 they make use of various block layer definitions and facilities.
 20
 21	 Say Y here unless you know you really don't want to mount disks and
 22	 suchlike.
 23
 24if BLOCK
 25
 26config LBDAF
 27	bool "Support for large (2TB+) block devices and files"
 28	depends on !64BIT
 29	default y
 30	help
 31	  Enable block devices or files of size 2TB and larger.
 
 
 
 
 32
 33	  This option is required to support the full capacity of large
 34	  (2TB+) block devices, including RAID, disk, Network Block Device,
 35	  Logical Volume Manager (LVM) and loopback.
 36	
 37	  This option also enables support for single files larger than
 38	  2TB.
 39
 40	  The ext4 filesystem requires that this feature be enabled in
 41	  order to support filesystems that have the huge_file feature
 42	  enabled.  Otherwise, it will refuse to mount in the read-write
 43	  mode any filesystems that use the huge_file feature, which is
 44	  enabled by default by mke2fs.ext4.
 45
 46	  The GFS2 filesystem also requires this feature.
 
 47
 48	  If unsure, say Y.
 
 49
 50config BLK_DEV_BSG
 51	bool "Block layer SG support v4"
 52	default y
 53	help
 54	  Saying Y here will enable generic SG (SCSI generic) v4 support
 55	  for any block device.
 56
 57	  Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4
 58	  can handle complicated SCSI commands: tagged variable length cdbs
 59	  with bidirectional data transfers and generic request/response
 60	  protocols (e.g. Task Management Functions and SMP in Serial
 61	  Attached SCSI).
 62
 63	  This option is required by recent UDEV versions to properly
 64	  access device serial numbers, etc.
 65
 66	  If unsure, say Y.
 67
 68config BLK_DEV_BSGLIB
 69	bool "Block layer SG support v4 helper lib"
 70	default n
 71	select BLK_DEV_BSG
 72	help
 73	  Subsystems will normally enable this if needed. Users will not
 74	  normally need to manually enable this.
 75
 76	  If unsure, say N.
 77
 78config BLK_DEV_INTEGRITY
 79	bool "Block layer data integrity support"
 80	select CRC_T10DIF if BLK_DEV_INTEGRITY
 81	---help---
 82	Some storage devices allow extra information to be
 83	stored/retrieved to help protect the data.  The block layer
 84	data integrity option provides hooks which can be used by
 85	filesystems to ensure better data integrity.
 86
 87	Say yes here if you have a storage device that provides the
 88	T10/SCSI Data Integrity Field or the T13/ATA External Path
 89	Protection.  If in doubt, say N.
 90
 91config BLK_DEV_DAX
 92	bool "Block device DAX support"
 93	depends on FS_DAX
 94	depends on BROKEN
 95	help
 96	  When DAX support is available (CONFIG_FS_DAX) raw block
 97	  devices can also support direct userspace access to the
 98	  storage capacity via MMAP(2) similar to a file on a
 99	  DAX-enabled filesystem.  However, the DAX I/O-path disables
100	  some standard I/O-statistics, and the MMAP(2) path has some
101	  operational differences due to bypassing the page
102	  cache.  If in doubt, say N.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
103
104config BLK_DEV_THROTTLING
105	bool "Block layer bio throttling support"
106	depends on BLK_CGROUP=y
107	default n
108	---help---
109	Block layer bio throttling support. It can be used to limit
110	the IO rate to a device. IO rate policies are per cgroup and
111	one needs to mount and use blkio cgroup controller for creating
112	cgroups and specifying per device IO rate policies.
113
114	See Documentation/cgroups/blkio-controller.txt for more information.
 
 
 
 
 
 
 
 
 
115
116config BLK_CMDLINE_PARSER
117	bool "Block device command line partition parser"
118	default n
119	---help---
120	Enabling this option allows you to specify the partition layout from
121	the kernel boot args.  This is typically of use for embedded devices
122	which don't otherwise have any standardized method for listing the
123	partitions on a block device.
124
125	See Documentation/block/cmdline-partition.txt for more information.
 
 
 
 
 
 
 
126
127menu "Partition Types"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
128
129source "block/partitions/Kconfig"
130
131endmenu
 
 
 
 
 
 
 
 
 
132
133endif # BLOCK
 
 
134
135config BLOCK_COMPAT
136	bool
137	depends on BLOCK && COMPAT
138	default y
139
140source block/Kconfig.iosched