# SPDX-License-Identifier: GPL-2.0
#
# Block layer core configuration
#
menuconfig BLOCK
bool "Enable the block layer" if EXPERT
default y
select SBITMAP
select SRCU
help
Provide block layer support for the kernel.
Disable this option to remove the block layer support from the
kernel. This may be useful for embedded devices.
If this option is disabled:
- block device files will become unusable
- some filesystems (such as ext3) will become unavailable.
Also, SCSI character devices and USB storage will be disabled since
they make use of various block layer definitions and facilities.
Say Y here unless you know you really don't want to mount disks and
suchlike.
if BLOCK
config BLK_RQ_ALLOC_TIME
bool
config BLK_SCSI_REQUEST
bool
config BLK_CGROUP_RWSTAT
bool
config BLK_DEV_BSG
bool "Block layer SG support v4"
default y
select BLK_SCSI_REQUEST
help
Saying Y here will enable generic SG (SCSI generic) v4 support
for any block device.
Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4
can handle complicated SCSI commands: tagged variable length cdbs
with bidirectional data transfers and generic request/response
protocols (e.g. Task Management Functions and SMP in Serial
Attached SCSI).
This option is required by recent UDEV versions to properly
access device serial numbers, etc.
If unsure, say Y.
config BLK_DEV_BSGLIB
bool "Block layer SG support v4 helper lib"
select BLK_DEV_BSG
select BLK_SCSI_REQUEST
help
Subsystems will normally enable this if needed. Users will not
normally need to manually enable this.
If unsure, say N.
config BLK_DEV_INTEGRITY
bool "Block layer data integrity support"
---help---
Some storage devices allow extra information to be
stored/retrieved to help protect the data. The block layer
data integrity option provides hooks which can be used by
filesystems to ensure better data integrity.
Say yes here if you have a storage device that provides the
T10/SCSI Data Integrity Field or the T13/ATA External Path
Protection. If in doubt, say N.
config BLK_DEV_INTEGRITY_T10
tristate
depends on BLK_DEV_INTEGRITY
select CRC_T10DIF
config BLK_DEV_ZONED
bool "Zoned block device support"
---help---
Block layer zoned block device support. This option enables
support for ZAC/ZBC/ZNS host-managed and host-aware zoned block
devices.
Say yes here if you have a ZAC, ZBC, or ZNS storage device.
config BLK_DEV_THROTTLING
bool "Block layer bio throttling support"
depends on BLK_CGROUP=y
select BLK_CGROUP_RWSTAT
---help---
Block layer bio throttling support. It can be used to limit
the IO rate to a device. IO rate policies are per cgroup and
one needs to mount and use blkio cgroup controller for creating
cgroups and specifying per device IO rate policies.
See Documentation/cgroup-v1/blkio-controller.txt for more information.
config BLK_DEV_THROTTLING_LOW
bool "Block throttling .low limit interface support (EXPERIMENTAL)"
depends on BLK_DEV_THROTTLING
---help---
Add .low limit interface for block throttling. The low limit is a best
effort limit to prioritize cgroups. Depending on the setting, the limit
can be used to protect cgroups in terms of bandwidth/iops and better
utilize disk resource.
Note, this is an experimental interface and could be changed someday.
config BLK_CMDLINE_PARSER
bool "Block device command line partition parser"
---help---
Enabling this option allows you to specify the partition layout from
the kernel boot args. This is typically of use for embedded devices
which don't otherwise have any standardized method for listing the
partitions on a block device.
See Documentation/block/cmdline-partition.txt for more information.
config BLK_WBT
bool "Enable support for block device writeback throttling"
---help---
Enabling this option enables the block layer to throttle buffered
background writeback from the VM, making it more smooth and having
less impact on foreground operations. The throttling is done
dynamically on an algorithm loosely based on CoDel, factoring in
the realtime performance of the disk.
config BLK_CGROUP_IOLATENCY
bool "Enable support for latency based cgroup IO protection"
depends on BLK_CGROUP=y
---help---
Enabling this option enables the .latency interface for IO throttling.
The IO controller will attempt to maintain average IO latencies below
the configured latency target, throttling anybody with a higher latency
target than the victimized group.
Note, this is an experimental interface and could be changed someday.
config BLK_CGROUP_FC_APPID
bool "Enable support to track FC I/O Traffic across cgroup applications"
depends on BLK_CGROUP=y
help
Enabling this option enables the support to track FC I/O traffic across
cgroup applications. It enables the Fabric and the storage targets to
identify, monitor, and handle FC traffic based on VM tags by inserting
application specific identification into the FC frame.
config BLK_CGROUP_IOCOST
bool "Enable support for cost model based cgroup IO controller"
depends on BLK_CGROUP=y
select BLK_RQ_ALLOC_TIME
---help---
Enabling this option enables the .weight interface for cost
model based proportional IO control. The IO controller
distributes IO capacity between different groups based on
their share of the overall weight distribution.
config BLK_WBT_MQ
bool "Multiqueue writeback throttling"
default y
depends on BLK_WBT
---help---
Enable writeback throttling by default on multiqueue devices.
config BLK_CGROUP_IOPRIO
bool "Cgroup I/O controller for assigning an I/O priority class"
depends on BLK_CGROUP
help
Enable the .prio interface for assigning an I/O priority class to
requests. The I/O priority class affects the order in which an I/O
scheduler and block devices process requests. Only some I/O schedulers
and some block devices support I/O priorities.
config BLK_DEBUG_FS
bool "Block layer debugging information in debugfs"
default y
depends on DEBUG_FS
---help---
Include block layer debugging information in debugfs. This information
is mostly useful for kernel developers, but it doesn't incur any cost
at runtime.
Unless you are building a kernel for a tiny system, you should
say Y here.
config BLK_DEBUG_FS_ZONED
bool
default BLK_DEBUG_FS && BLK_DEV_ZONED
config BLK_SED_OPAL
bool "Logic for interfacing with Opal enabled SEDs"
---help---
Builds Logic for interfacing with Opal enabled controllers.
Enabling this option enables users to setup/unlock/lock
Locking ranges for SED devices using the Opal protocol.
menu "Partition Types"
source "block/partitions/Kconfig"
endmenu
endif # BLOCK
config BLOCK_COMPAT
bool
depends on BLOCK && COMPAT
default y
config BLK_MQ_PCI
bool
depends on BLOCK && PCI
default y
config BLK_MQ_VIRTIO
bool
depends on BLOCK && VIRTIO
default y
config BLK_MQ_RDMA
bool
depends on BLOCK && INFINIBAND
default y
config BLK_PM
def_bool BLOCK && PM
source block/Kconfig.iosched
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