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