# 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 LBDAF
  	bool "Support for large (2TB+) block devices and files"
  	depends on !64BIT
  	default y
  	help
  	  Enable block devices or files of size 2TB and larger.
  
  	  This option is required to support the full capacity of large
  	  (2TB+) block devices, including RAID, disk, Network Block Device,
  	  Logical Volume Manager (LVM) and loopback.
  	
  	  This option also enables support for single files larger than
  	  2TB.
  
  	  The ext4 filesystem requires that this feature be enabled in
  	  order to support filesystems that have the huge_file feature
  	  enabled.  Otherwise, it will refuse to mount in the read-write
  	  mode any filesystems that use the huge_file feature, which is
  	  enabled by default by mke2fs.ext4.
  
  	  The GFS2 filesystem also requires this feature.
  
  	  If unsure, say Y.
  
  config BLK_SCSI_REQUEST
  	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"
  	default n
  	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"
  	select CRC_T10DIF if 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/SCSI Data Integrity Field or the T13/ATA External Path
  	Protection.  If in doubt, say N.
  
  config BLK_DEV_ZONED
  	bool "Zoned block device support"
  	---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 BLK_DEV_THROTTLING
  	bool "Block layer bio throttling support"
  	depends on BLK_CGROUP=y
  	default n
  	---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/cgroups/blkio-controller.txt for more information.
  
  config BLK_DEV_THROTTLING_LOW
  	bool "Block throttling .low limit interface support (EXPERIMENTAL)"
  	depends on BLK_DEV_THROTTLING
  	default n
  	---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"
  	default n
  	---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"
  	default n
  	---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_WBT_SQ
  	bool "Single queue writeback throttling"
  	default n
  	depends on BLK_WBT
  	---help---
  	Enable writeback throttling by default on legacy single queue devices
  
  config BLK_WBT_MQ
  	bool "Multiqueue writeback throttling"
  	default y
  	depends on 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 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_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
  
  source block/Kconfig.iosched