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# SPDX-License-Identifier: GPL-2.0
#
# Block layer core configuration
#
menuconfig CONFIG_BLOCK
       bool "Enable the block layer" if CONFIG_EXPERT
       default y
       select CONFIG_SBITMAP
       select CONFIG_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, CONFIG_SCSI character devices and CONFIG_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 CONFIG_BLOCK

config CONFIG_BLK_RQ_ALLOC_TIME
	bool

config CONFIG_BLK_SCSI_REQUEST
	bool

config CONFIG_BLK_DEV_BSG
	bool "Block layer SG support v4"
	default y
	select CONFIG_BLK_SCSI_REQUEST
	help
	  Saying Y here will enable generic SG (CONFIG_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 CONFIG_SCSI commands: tagged variable length cdbs
	  with bidirectional data transfers and generic request/response
	  protocols (e.g. Task Management Functions and CONFIG_SMP in Serial
	  Attached CONFIG_SCSI).

	  This option is required by recent UDEV versions to properly
	  access device serial numbers, etc.

	  If unsure, say Y.

config CONFIG_BLK_DEV_BSGLIB
	bool "Block layer SG support v4 helper lib"
	select CONFIG_BLK_DEV_BSG
	select CONFIG_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 CONFIG_BLK_DEV_INTEGRITY
	bool "Block layer data integrity support"
	select CONFIG_CRC_T10DIF if CONFIG_BLK_DEV_INTEGRITY
	---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/CONFIG_SCSI Data Integrity Field or the T13/CONFIG_ATA External Path
	Protection.  If in doubt, say N.

config CONFIG_BLK_DEV_ZONED
	bool "Zoned block device support"
	select CONFIG_MQ_IOSCHED_DEADLINE
	---help---
	Block layer zoned block device support. This option enables
	support for ZAC/ZBC host-managed and host-aware zoned block devices.

	Say yes here if you have a ZAC or ZBC storage device.

config CONFIG_BLK_DEV_THROTTLING
	bool "Block layer bio throttling support"
	depends on CONFIG_BLK_CGROUP=y
	---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/admin-guide/cgroup-v1/blkio-controller.rst for more information.

config CONFIG_BLK_DEV_THROTTLING_LOW
	bool "Block throttling .low limit interface support (EXPERIMENTAL)"
	depends on CONFIG_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 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.rst for more information.

config 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 CONFIG_BLK_CGROUP_IOLATENCY
	bool "Enable support for latency based cgroup IO protection"
	depends on CONFIG_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 CONFIG_BLK_CGROUP_IOCOST
	bool "Enable support for cost model based cgroup IO controller"
	depends on CONFIG_BLK_CGROUP=y
	select CONFIG_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 CONFIG_BLK_WBT_MQ
	bool "Multiqueue writeback throttling"
	default y
	depends on CONFIG_BLK_WBT
	---help---
	Enable writeback throttling by default on multiqueue devices.
	Multiqueue currently doesn't have support for IO scheduling,
	enabling this option is recommended.

config CONFIG_BLK_DEBUG_FS
	bool "Block layer debugging information in debugfs"
	default y
	depends on CONFIG_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 CONFIG_BLK_DEBUG_FS_ZONED
       bool
       default CONFIG_BLK_DEBUG_FS && CONFIG_BLK_DEV_ZONED

config 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 # CONFIG_BLOCK

config CONFIG_BLOCK_COMPAT
	bool
	depends on CONFIG_BLOCK && CONFIG_COMPAT
	default y

config CONFIG_BLK_MQ_PCI
	bool
	depends on CONFIG_BLOCK && CONFIG_PCI
	default y

config CONFIG_BLK_MQ_VIRTIO
	bool
	depends on CONFIG_BLOCK && CONFIG_VIRTIO
	default y

config CONFIG_BLK_MQ_RDMA
	bool
	depends on CONFIG_BLOCK && CONFIG_INFINIBAND
	default y

config CONFIG_BLK_PM
	def_bool CONFIG_BLOCK && CONFIG_PM

source "block/Kconfig.iosched"