# 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_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" 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 ---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_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_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"