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