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 SBITMAP 9 select SRCU 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 BLK_SCSI_REQUEST 30 bool 31 32config BLK_DEV_BSG 33 bool "Block layer SG support v4" 34 default y 35 select BLK_SCSI_REQUEST 36 help 37 Saying Y here will enable generic SG (SCSI generic) v4 support 38 for any block device. 39 40 Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4 41 can handle complicated SCSI commands: tagged variable length cdbs 42 with bidirectional data transfers and generic request/response 43 protocols (e.g. Task Management Functions and SMP in Serial 44 Attached SCSI). 45 46 This option is required by recent UDEV versions to properly 47 access device serial numbers, etc. 48 49 If unsure, say Y. 50 51config BLK_DEV_BSGLIB 52 bool "Block layer SG support v4 helper lib" 53 select BLK_DEV_BSG 54 select BLK_SCSI_REQUEST 55 help 56 Subsystems will normally enable this if needed. Users will not 57 normally need to manually enable this. 58 59 If unsure, say N. 60 61config BLK_DEV_INTEGRITY 62 bool "Block layer data integrity support" 63 select CRC_T10DIF if BLK_DEV_INTEGRITY 64 ---help--- 65 Some storage devices allow extra information to be 66 stored/retrieved to help protect the data. The block layer 67 data integrity option provides hooks which can be used by 68 filesystems to ensure better data integrity. 69 70 Say yes here if you have a storage device that provides the 71 T10/SCSI Data Integrity Field or the T13/ATA External Path 72 Protection. If in doubt, say N. 73 74config BLK_DEV_ZONED 75 bool "Zoned block device support" 76 select MQ_IOSCHED_DEADLINE 77 ---help--- 78 Block layer zoned block device support. This option enables 79 support for ZAC/ZBC host-managed and host-aware zoned block devices. 80 81 Say yes here if you have a ZAC or ZBC storage device. 82 83config BLK_DEV_THROTTLING 84 bool "Block layer bio throttling support" 85 depends on BLK_CGROUP=y 86 ---help--- 87 Block layer bio throttling support. It can be used to limit 88 the IO rate to a device. IO rate policies are per cgroup and 89 one needs to mount and use blkio cgroup controller for creating 90 cgroups and specifying per device IO rate policies. 91 92 See Documentation/cgroup-v1/blkio-controller.rst for more information. 93 94config BLK_DEV_THROTTLING_LOW 95 bool "Block throttling .low limit interface support (EXPERIMENTAL)" 96 depends on BLK_DEV_THROTTLING 97 ---help--- 98 Add .low limit interface for block throttling. The low limit is a best 99 effort limit to prioritize cgroups. Depending on the setting, the limit 100 can be used to protect cgroups in terms of bandwidth/iops and better 101 utilize disk resource. 102 103 Note, this is an experimental interface and could be changed someday. 104 105config BLK_CMDLINE_PARSER 106 bool "Block device command line partition parser" 107 ---help--- 108 Enabling this option allows you to specify the partition layout from 109 the kernel boot args. This is typically of use for embedded devices 110 which don't otherwise have any standardized method for listing the 111 partitions on a block device. 112 113 See Documentation/block/cmdline-partition.txt for more information. 114 115config BLK_WBT 116 bool "Enable support for block device writeback throttling" 117 ---help--- 118 Enabling this option enables the block layer to throttle buffered 119 background writeback from the VM, making it more smooth and having 120 less impact on foreground operations. The throttling is done 121 dynamically on an algorithm loosely based on CoDel, factoring in 122 the realtime performance of the disk. 123 124config BLK_CGROUP_IOLATENCY 125 bool "Enable support for latency based cgroup IO protection" 126 depends on BLK_CGROUP=y 127 ---help--- 128 Enabling this option enables the .latency interface for IO throttling. 129 The IO controller will attempt to maintain average IO latencies below 130 the configured latency target, throttling anybody with a higher latency 131 target than the victimized group. 132 133 Note, this is an experimental interface and could be changed someday. 134 135config BLK_WBT_MQ 136 bool "Multiqueue writeback throttling" 137 default y 138 depends on BLK_WBT 139 ---help--- 140 Enable writeback throttling by default on multiqueue devices. 141 Multiqueue currently doesn't have support for IO scheduling, 142 enabling this option is recommended. 143 144config BLK_DEBUG_FS 145 bool "Block layer debugging information in debugfs" 146 default y 147 depends on DEBUG_FS 148 ---help--- 149 Include block layer debugging information in debugfs. This information 150 is mostly useful for kernel developers, but it doesn't incur any cost 151 at runtime. 152 153 Unless you are building a kernel for a tiny system, you should 154 say Y here. 155 156config BLK_DEBUG_FS_ZONED 157 bool 158 default BLK_DEBUG_FS && BLK_DEV_ZONED 159 160config BLK_SED_OPAL 161 bool "Logic for interfacing with Opal enabled SEDs" 162 ---help--- 163 Builds Logic for interfacing with Opal enabled controllers. 164 Enabling this option enables users to setup/unlock/lock 165 Locking ranges for SED devices using the Opal protocol. 166 167menu "Partition Types" 168 169source "block/partitions/Kconfig" 170 171endmenu 172 173endif # BLOCK 174 175config BLOCK_COMPAT 176 bool 177 depends on BLOCK && COMPAT 178 default y 179 180config BLK_MQ_PCI 181 bool 182 depends on BLOCK && PCI 183 default y 184 185config BLK_MQ_VIRTIO 186 bool 187 depends on BLOCK && VIRTIO 188 default y 189 190config BLK_MQ_RDMA 191 bool 192 depends on BLOCK && INFINIBAND 193 default y 194 195config BLK_PM 196 def_bool BLOCK && PM 197 198source "block/Kconfig.iosched" 199