block/Kconfig

   1 # SPDX-License-Identifier: GPL-2.0
   2 #
   3 # Block layer core configuration
   4 #
   5 menuconfig 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
  27 if BLOCK
  28
  29 config 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
  53 config BLK_SCSI_REQUEST
  54         bool
  55
  56 config 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
  75 config 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
  86 config 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
  99 config 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
 107 config 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
 119 config 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
 131 config 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
 142 config 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
 152 config BLK_CGROUP_IOLATENCY
 153         bool "Enable support for latency based cgroup IO protection"
 154         depends on BLK_CGROUP=y
 155         default n
 156         ---help---
 157         Enabling this option enables the .latency interface for IO throttling.
 158         The IO controller will attempt to maintain average IO latencies below
 159         the configured latency target, throttling anybody with a higher latency
 160         target than the victimized group.
 161
 162         Note, this is an experimental interface and could be changed someday.
 163
 164 config BLK_WBT_SQ
 165         bool "Single queue writeback throttling"
 166         default n
 167         depends on BLK_WBT
 168         ---help---
 169         Enable writeback throttling by default on legacy single queue devices
 170
 171 config BLK_WBT_MQ
 172         bool "Multiqueue writeback throttling"
 173         default y
 174         depends on BLK_WBT
 175         ---help---
 176         Enable writeback throttling by default on multiqueue devices.
 177         Multiqueue currently doesn't have support for IO scheduling,
 178         enabling this option is recommended.
 179
 180 config BLK_DEBUG_FS
 181         bool "Block layer debugging information in debugfs"
 182         default y
 183         depends on DEBUG_FS
 184         ---help---
 185         Include block layer debugging information in debugfs. This information
 186         is mostly useful for kernel developers, but it doesn't incur any cost
 187         at runtime.
 188
 189         Unless you are building a kernel for a tiny system, you should
 190         say Y here.
 191
 192 config BLK_DEBUG_FS_ZONED
 193        bool
 194        default BLK_DEBUG_FS && BLK_DEV_ZONED
 195
 196 config BLK_SED_OPAL
 197         bool "Logic for interfacing with Opal enabled SEDs"
 198         ---help---
 199         Builds Logic for interfacing with Opal enabled controllers.
 200         Enabling this option enables users to setup/unlock/lock
 201         Locking ranges for SED devices using the Opal protocol.
 202
 203 menu "Partition Types"
 204
 205 source "block/partitions/Kconfig"
 206
 207 endmenu
 208
 209 endif # BLOCK
 210
 211 config BLOCK_COMPAT
 212         bool
 213         depends on BLOCK && COMPAT
 214         default y
 215
 216 config BLK_MQ_PCI
 217         bool
 218         depends on BLOCK && PCI
 219         default y
 220
 221 config BLK_MQ_VIRTIO
 222         bool
 223         depends on BLOCK && VIRTIO
 224         default y
 225
 226 config BLK_MQ_RDMA
 227         bool
 228         depends on BLOCK && INFINIBAND
 229         default y
 230
 231 source block/Kconfig.iosched