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_RQ_ALLOC_TIME 30 bool 31 32config BLK_SCSI_REQUEST 33 bool 34 35config BLK_CGROUP_RWSTAT 36 bool 37 38config BLK_DEV_BSG 39 bool "Block layer SG support v4" 40 default y 41 select BLK_SCSI_REQUEST 42 help 43 Saying Y here will enable generic SG (SCSI generic) v4 support 44 for any block device. 45 46 Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4 47 can handle complicated SCSI commands: tagged variable length cdbs 48 with bidirectional data transfers and generic request/response 49 protocols (e.g. Task Management Functions and SMP in Serial 50 Attached SCSI). 51 52 This option is required by recent UDEV versions to properly 53 access device serial numbers, etc. 54 55 If unsure, say Y. 56 57config BLK_DEV_BSGLIB 58 bool "Block layer SG support v4 helper lib" 59 select BLK_DEV_BSG 60 select BLK_SCSI_REQUEST 61 help 62 Subsystems will normally enable this if needed. Users will not 63 normally need to manually enable this. 64 65 If unsure, say N. 66 67config BLK_DEV_INTEGRITY 68 bool "Block layer data integrity support" 69 select CRC_T10DIF if BLK_DEV_INTEGRITY 70 ---help--- 71 Some storage devices allow extra information to be 72 stored/retrieved to help protect the data. The block layer 73 data integrity option provides hooks which can be used by 74 filesystems to ensure better data integrity. 75 76 Say yes here if you have a storage device that provides the 77 T10/SCSI Data Integrity Field or the T13/ATA External Path 78 Protection. If in doubt, say N. 79 80config BLK_DEV_ZONED 81 bool "Zoned block device support" 82 select MQ_IOSCHED_DEADLINE 83 ---help--- 84 Block layer zoned block device support. This option enables 85 support for ZAC/ZBC host-managed and host-aware zoned block devices. 86 87 Say yes here if you have a ZAC or ZBC storage device. 88 89config BLK_DEV_THROTTLING 90 bool "Block layer bio throttling support" 91 depends on BLK_CGROUP=y 92 select BLK_CGROUP_RWSTAT 93 ---help--- 94 Block layer bio throttling support. It can be used to limit 95 the IO rate to a device. IO rate policies are per cgroup and 96 one needs to mount and use blkio cgroup controller for creating 97 cgroups and specifying per device IO rate policies. 98 99 See Documentation/admin-guide/cgroup-v1/blkio-controller.rst for more information. 100 101config BLK_DEV_THROTTLING_LOW 102 bool "Block throttling .low limit interface support (EXPERIMENTAL)" 103 depends on BLK_DEV_THROTTLING 104 ---help--- 105 Add .low limit interface for block throttling. The low limit is a best 106 effort limit to prioritize cgroups. Depending on the setting, the limit 107 can be used to protect cgroups in terms of bandwidth/iops and better 108 utilize disk resource. 109 110 Note, this is an experimental interface and could be changed someday. 111 112config BLK_CMDLINE_PARSER 113 bool "Block device command line partition parser" 114 ---help--- 115 Enabling this option allows you to specify the partition layout from 116 the kernel boot args. This is typically of use for embedded devices 117 which don't otherwise have any standardized method for listing the 118 partitions on a block device. 119 120 See Documentation/block/cmdline-partition.rst for more information. 121 122config BLK_WBT 123 bool "Enable support for block device writeback throttling" 124 ---help--- 125 Enabling this option enables the block layer to throttle buffered 126 background writeback from the VM, making it more smooth and having 127 less impact on foreground operations. The throttling is done 128 dynamically on an algorithm loosely based on CoDel, factoring in 129 the realtime performance of the disk. 130 131config BLK_CGROUP_IOLATENCY 132 bool "Enable support for latency based cgroup IO protection" 133 depends on BLK_CGROUP=y 134 ---help--- 135 Enabling this option enables the .latency interface for IO throttling. 136 The IO controller will attempt to maintain average IO latencies below 137 the configured latency target, throttling anybody with a higher latency 138 target than the victimized group. 139 140 Note, this is an experimental interface and could be changed someday. 141 142config BLK_CGROUP_IOCOST 143 bool "Enable support for cost model based cgroup IO controller" 144 depends on BLK_CGROUP=y 145 select BLK_RQ_ALLOC_TIME 146 ---help--- 147 Enabling this option enables the .weight interface for cost 148 model based proportional IO control. The IO controller 149 distributes IO capacity between different groups based on 150 their share of the overall weight distribution. 151 152config BLK_WBT_MQ 153 bool "Multiqueue writeback throttling" 154 default y 155 depends on BLK_WBT 156 ---help--- 157 Enable writeback throttling by default on multiqueue devices. 158 Multiqueue currently doesn't have support for IO scheduling, 159 enabling this option is recommended. 160 161config BLK_DEBUG_FS 162 bool "Block layer debugging information in debugfs" 163 default y 164 depends on DEBUG_FS 165 ---help--- 166 Include block layer debugging information in debugfs. This information 167 is mostly useful for kernel developers, but it doesn't incur any cost 168 at runtime. 169 170 Unless you are building a kernel for a tiny system, you should 171 say Y here. 172 173config BLK_DEBUG_FS_ZONED 174 bool 175 default BLK_DEBUG_FS && BLK_DEV_ZONED 176 177config BLK_SED_OPAL 178 bool "Logic for interfacing with Opal enabled SEDs" 179 ---help--- 180 Builds Logic for interfacing with Opal enabled controllers. 181 Enabling this option enables users to setup/unlock/lock 182 Locking ranges for SED devices using the Opal protocol. 183 184menu "Partition Types" 185 186source "block/partitions/Kconfig" 187 188endmenu 189 190endif # BLOCK 191 192config BLOCK_COMPAT 193 bool 194 depends on BLOCK && COMPAT 195 default y 196 197config BLK_MQ_PCI 198 bool 199 depends on BLOCK && PCI 200 default y 201 202config BLK_MQ_VIRTIO 203 bool 204 depends on BLOCK && VIRTIO 205 default y 206 207config BLK_MQ_RDMA 208 bool 209 depends on BLOCK && INFINIBAND 210 default y 211 212config BLK_PM 213 def_bool BLOCK && PM 214 215source "block/Kconfig.iosched" 216