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 ---help--- 70 Some storage devices allow extra information to be 71 stored/retrieved to help protect the data. The block layer 72 data integrity option provides hooks which can be used by 73 filesystems to ensure better data integrity. 74 75 Say yes here if you have a storage device that provides the 76 T10/SCSI Data Integrity Field or the T13/ATA External Path 77 Protection. If in doubt, say N. 78 79config BLK_DEV_INTEGRITY_T10 80 tristate 81 depends on BLK_DEV_INTEGRITY 82 select CRC_T10DIF 83 84config BLK_DEV_ZONED 85 bool "Zoned block device support" 86 select MQ_IOSCHED_DEADLINE 87 ---help--- 88 Block layer zoned block device support. This option enables 89 support for ZAC/ZBC host-managed and host-aware zoned block devices. 90 91 Say yes here if you have a ZAC or ZBC storage device. 92 93config BLK_DEV_THROTTLING 94 bool "Block layer bio throttling support" 95 depends on BLK_CGROUP=y 96 select BLK_CGROUP_RWSTAT 97 ---help--- 98 Block layer bio throttling support. It can be used to limit 99 the IO rate to a device. IO rate policies are per cgroup and 100 one needs to mount and use blkio cgroup controller for creating 101 cgroups and specifying per device IO rate policies. 102 103 See Documentation/admin-guide/cgroup-v1/blkio-controller.rst for more information. 104 105config BLK_DEV_THROTTLING_LOW 106 bool "Block throttling .low limit interface support (EXPERIMENTAL)" 107 depends on BLK_DEV_THROTTLING 108 ---help--- 109 Add .low limit interface for block throttling. The low limit is a best 110 effort limit to prioritize cgroups. Depending on the setting, the limit 111 can be used to protect cgroups in terms of bandwidth/iops and better 112 utilize disk resource. 113 114 Note, this is an experimental interface and could be changed someday. 115 116config BLK_CMDLINE_PARSER 117 bool "Block device command line partition parser" 118 ---help--- 119 Enabling this option allows you to specify the partition layout from 120 the kernel boot args. This is typically of use for embedded devices 121 which don't otherwise have any standardized method for listing the 122 partitions on a block device. 123 124 See Documentation/block/cmdline-partition.rst for more information. 125 126config BLK_WBT 127 bool "Enable support for block device writeback throttling" 128 ---help--- 129 Enabling this option enables the block layer to throttle buffered 130 background writeback from the VM, making it more smooth and having 131 less impact on foreground operations. The throttling is done 132 dynamically on an algorithm loosely based on CoDel, factoring in 133 the realtime performance of the disk. 134 135config BLK_CGROUP_IOLATENCY 136 bool "Enable support for latency based cgroup IO protection" 137 depends on BLK_CGROUP=y 138 ---help--- 139 Enabling this option enables the .latency interface for IO throttling. 140 The IO controller will attempt to maintain average IO latencies below 141 the configured latency target, throttling anybody with a higher latency 142 target than the victimized group. 143 144 Note, this is an experimental interface and could be changed someday. 145 146config BLK_CGROUP_IOCOST 147 bool "Enable support for cost model based cgroup IO controller" 148 depends on BLK_CGROUP=y 149 select BLK_RQ_ALLOC_TIME 150 ---help--- 151 Enabling this option enables the .weight interface for cost 152 model based proportional IO control. The IO controller 153 distributes IO capacity between different groups based on 154 their share of the overall weight distribution. 155 156config BLK_WBT_MQ 157 bool "Multiqueue writeback throttling" 158 default y 159 depends on BLK_WBT 160 ---help--- 161 Enable writeback throttling by default on multiqueue devices. 162 Multiqueue currently doesn't have support for IO scheduling, 163 enabling this option is recommended. 164 165config BLK_DEBUG_FS 166 bool "Block layer debugging information in debugfs" 167 default y 168 depends on DEBUG_FS 169 ---help--- 170 Include block layer debugging information in debugfs. This information 171 is mostly useful for kernel developers, but it doesn't incur any cost 172 at runtime. 173 174 Unless you are building a kernel for a tiny system, you should 175 say Y here. 176 177config BLK_DEBUG_FS_ZONED 178 bool 179 default BLK_DEBUG_FS && BLK_DEV_ZONED 180 181config BLK_SED_OPAL 182 bool "Logic for interfacing with Opal enabled SEDs" 183 ---help--- 184 Builds Logic for interfacing with Opal enabled controllers. 185 Enabling this option enables users to setup/unlock/lock 186 Locking ranges for SED devices using the Opal protocol. 187 188menu "Partition Types" 189 190source "block/partitions/Kconfig" 191 192endmenu 193 194endif # BLOCK 195 196config BLOCK_COMPAT 197 bool 198 depends on BLOCK && COMPAT 199 default y 200 201config BLK_MQ_PCI 202 bool 203 depends on BLOCK && PCI 204 default y 205 206config BLK_MQ_VIRTIO 207 bool 208 depends on BLOCK && VIRTIO 209 default y 210 211config BLK_MQ_RDMA 212 bool 213 depends on BLOCK && INFINIBAND 214 default y 215 216config BLK_PM 217 def_bool BLOCK && PM 218 219source "block/Kconfig.iosched" 220