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