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 LBDAF 30 bool "Support for large (2TB+) block devices and files" 31 depends on !64BIT 32 default y 33 help 34 Enable block devices or files of size 2TB and larger. 35 36 This option is required to support the full capacity of large 37 (2TB+) block devices, including RAID, disk, Network Block Device, 38 Logical Volume Manager (LVM) and loopback. 39 40 This option also enables support for single files larger than 41 2TB. 42 43 The ext4 filesystem requires that this feature be enabled in 44 order to support filesystems that have the huge_file feature 45 enabled. Otherwise, it will refuse to mount in the read-write 46 mode any filesystems that use the huge_file feature, which is 47 enabled by default by mke2fs.ext4. 48 49 The GFS2 filesystem also requires this feature. 50 51 If unsure, say Y. 52 53config BLK_SCSI_REQUEST 54 bool 55 56config BLK_DEV_BSG 57 bool "Block layer SG support v4" 58 default y 59 select BLK_SCSI_REQUEST 60 help 61 Saying Y here will enable generic SG (SCSI generic) v4 support 62 for any block device. 63 64 Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4 65 can handle complicated SCSI commands: tagged variable length cdbs 66 with bidirectional data transfers and generic request/response 67 protocols (e.g. Task Management Functions and SMP in Serial 68 Attached SCSI). 69 70 This option is required by recent UDEV versions to properly 71 access device serial numbers, etc. 72 73 If unsure, say Y. 74 75config BLK_DEV_BSGLIB 76 bool "Block layer SG support v4 helper lib" 77 select BLK_DEV_BSG 78 select BLK_SCSI_REQUEST 79 help 80 Subsystems will normally enable this if needed. Users will not 81 normally need to manually enable this. 82 83 If unsure, say N. 84 85config BLK_DEV_INTEGRITY 86 bool "Block layer data integrity support" 87 select CRC_T10DIF if BLK_DEV_INTEGRITY 88 ---help--- 89 Some storage devices allow extra information to be 90 stored/retrieved to help protect the data. The block layer 91 data integrity option provides hooks which can be used by 92 filesystems to ensure better data integrity. 93 94 Say yes here if you have a storage device that provides the 95 T10/SCSI Data Integrity Field or the T13/ATA External Path 96 Protection. If in doubt, say N. 97 98config BLK_DEV_ZONED 99 bool "Zoned block device support" 100 ---help--- 101 Block layer zoned block device support. This option enables 102 support for ZAC/ZBC host-managed and host-aware zoned block devices. 103 104 Say yes here if you have a ZAC or ZBC storage device. 105 106config BLK_DEV_THROTTLING 107 bool "Block layer bio throttling support" 108 depends on BLK_CGROUP=y 109 ---help--- 110 Block layer bio throttling support. It can be used to limit 111 the IO rate to a device. IO rate policies are per cgroup and 112 one needs to mount and use blkio cgroup controller for creating 113 cgroups and specifying per device IO rate policies. 114 115 See Documentation/cgroup-v1/blkio-controller.txt for more information. 116 117config BLK_DEV_THROTTLING_LOW 118 bool "Block throttling .low limit interface support (EXPERIMENTAL)" 119 depends on BLK_DEV_THROTTLING 120 ---help--- 121 Add .low limit interface for block throttling. The low limit is a best 122 effort limit to prioritize cgroups. Depending on the setting, the limit 123 can be used to protect cgroups in terms of bandwidth/iops and better 124 utilize disk resource. 125 126 Note, this is an experimental interface and could be changed someday. 127 128config BLK_CMDLINE_PARSER 129 bool "Block device command line partition parser" 130 ---help--- 131 Enabling this option allows you to specify the partition layout from 132 the kernel boot args. This is typically of use for embedded devices 133 which don't otherwise have any standardized method for listing the 134 partitions on a block device. 135 136 See Documentation/block/cmdline-partition.txt for more information. 137 138config BLK_WBT 139 bool "Enable support for block device writeback throttling" 140 ---help--- 141 Enabling this option enables the block layer to throttle buffered 142 background writeback from the VM, making it more smooth and having 143 less impact on foreground operations. The throttling is done 144 dynamically on an algorithm loosely based on CoDel, factoring in 145 the realtime performance of the disk. 146 147config BLK_CGROUP_IOLATENCY 148 bool "Enable support for latency based cgroup IO protection" 149 depends on BLK_CGROUP=y 150 ---help--- 151 Enabling this option enables the .latency interface for IO throttling. 152 The IO controller will attempt to maintain average IO latencies below 153 the configured latency target, throttling anybody with a higher latency 154 target than the victimized group. 155 156 Note, this is an experimental interface and could be changed someday. 157 158config BLK_WBT_MQ 159 bool "Multiqueue writeback throttling" 160 default y 161 depends on BLK_WBT 162 ---help--- 163 Enable writeback throttling by default on multiqueue devices. 164 Multiqueue currently doesn't have support for IO scheduling, 165 enabling this option is recommended. 166 167config BLK_DEBUG_FS 168 bool "Block layer debugging information in debugfs" 169 default y 170 depends on DEBUG_FS 171 ---help--- 172 Include block layer debugging information in debugfs. This information 173 is mostly useful for kernel developers, but it doesn't incur any cost 174 at runtime. 175 176 Unless you are building a kernel for a tiny system, you should 177 say Y here. 178 179config BLK_DEBUG_FS_ZONED 180 bool 181 default BLK_DEBUG_FS && BLK_DEV_ZONED 182 183config BLK_SED_OPAL 184 bool "Logic for interfacing with Opal enabled SEDs" 185 ---help--- 186 Builds Logic for interfacing with Opal enabled controllers. 187 Enabling this option enables users to setup/unlock/lock 188 Locking ranges for SED devices using the Opal protocol. 189 190menu "Partition Types" 191 192source "block/partitions/Kconfig" 193 194endmenu 195 196endif # BLOCK 197 198config BLOCK_COMPAT 199 bool 200 depends on BLOCK && COMPAT 201 default y 202 203config BLK_MQ_PCI 204 bool 205 depends on BLOCK && PCI 206 default y 207 208config BLK_MQ_VIRTIO 209 bool 210 depends on BLOCK && VIRTIO 211 default y 212 213config BLK_MQ_RDMA 214 bool 215 depends on BLOCK && INFINIBAND 216 default y 217 218config BLK_PM 219 def_bool BLOCK && PM 220 221source "block/Kconfig.iosched" 222