1161748Scperciva# SPDX-License-Identifier: GPL-2.0 2161748Scperciva# 3161748Scperciva# Block layer core configuration 4161748Scperciva# 5161748Scpercivamenuconfig BLOCK 6161748Scperciva bool "Enable the block layer" if EXPERT 7161748Scperciva default y 8161748Scperciva select FS_IOMAP 9161748Scperciva select SBITMAP 10161748Scperciva help 11161748Scperciva Provide block layer support for the kernel. 12161748Scperciva 13161748Scperciva Disable this option to remove the block layer support from the 14161748Scperciva kernel. This may be useful for embedded devices. 15161748Scperciva 16161748Scperciva If this option is disabled: 17161748Scperciva 18161748Scperciva - block device files will become unusable 19161748Scperciva - some filesystems (such as ext3) will become unavailable. 20161748Scperciva 21161748Scperciva Also, SCSI character devices and USB storage will be disabled since 22161748Scperciva they make use of various block layer definitions and facilities. 23161748Scperciva 24181145Scperciva Say Y here unless you know you really don't want to mount disks and 25181145Scperciva suchlike. 26181145Scperciva 27181427Scpercivaif BLOCK 28181427Scperciva 29181427Scpercivaconfig BLOCK_LEGACY_AUTOLOAD 30181145Scperciva bool "Legacy autoloading support" 31161748Scperciva default y 32161748Scperciva help 33173564Scperciva Enable loading modules and creating block device instances based on 34174057Scperciva accesses through their device special file. This is a historic Linux 35161748Scperciva feature and makes no sense in a udev world where device files are 36173564Scperciva created on demand, but scripts that manually create device nodes and 37173564Scperciva then call losetup might rely on this behavior. 38257694Sglebius 39173564Scpercivaconfig BLK_RQ_ALLOC_TIME 40161748Scperciva bool 41161748Scperciva 42161748Scpercivaconfig BLK_CGROUP_RWSTAT 43161748Scperciva bool 44161748Scperciva 45161748Scpercivaconfig BLK_CGROUP_PUNT_BIO 46161748Scperciva bool 47161748Scperciva 48161748Scpercivaconfig BLK_DEV_BSG_COMMON 49161748Scperciva tristate 50161748Scperciva 51161748Scpercivaconfig BLK_ICQ 52161748Scperciva bool 53161748Scperciva 54161748Scpercivaconfig BLK_DEV_BSGLIB 55161748Scperciva bool "Block layer SG support v4 helper lib" 56161748Scperciva select BLK_DEV_BSG_COMMON 57161748Scperciva help 58161748Scperciva Subsystems will normally enable this if needed. Users will not 59161748Scperciva normally need to manually enable this. 60173564Scperciva 61173564Scperciva If unsure, say N. 62173564Scperciva 63173564Scpercivaconfig BLK_DEV_INTEGRITY 64173564Scperciva bool "Block layer data integrity support" 65173564Scperciva help 66196392Ssimon Some storage devices allow extra information to be 67196392Ssimon stored/retrieved to help protect the data. The block layer 68196392Ssimon data integrity option provides hooks which can be used by 69196392Ssimon filesystems to ensure better data integrity. 70196392Ssimon 71196392Ssimon Say yes here if you have a storage device that provides the 72196392Ssimon T10/SCSI Data Integrity Field or the T13/ATA External Path 73196392Ssimon Protection. If in doubt, say N. 74196392Ssimon 75196392Ssimonconfig BLK_DEV_INTEGRITY_T10 76196392Ssimon tristate 77 depends on BLK_DEV_INTEGRITY 78 select CRC_T10DIF 79 select CRC64_ROCKSOFT 80 81config BLK_DEV_WRITE_MOUNTED 82 bool "Allow writing to mounted block devices" 83 default y 84 help 85 When a block device is mounted, writing to its buffer cache is very 86 likely going to cause filesystem corruption. It is also rather easy to 87 crash the kernel in this way since the filesystem has no practical way 88 of detecting these writes to buffer cache and verifying its metadata 89 integrity. However there are some setups that need this capability 90 like running fsck on read-only mounted root device, modifying some 91 features on mounted ext4 filesystem, and similar. If you say N, the 92 kernel will prevent processes from writing to block devices that are 93 mounted by filesystems which provides some more protection from runaway 94 privileged processes and generally makes it much harder to crash 95 filesystem drivers. Note however that this does not prevent 96 underlying device(s) from being modified by other means, e.g. by 97 directly submitting SCSI commands or through access to lower layers of 98 storage stack. If in doubt, say Y. The configuration can be overridden 99 with the bdev_allow_write_mounted boot option. 100 101config BLK_DEV_ZONED 102 bool "Zoned block device support" 103 select MQ_IOSCHED_DEADLINE 104 help 105 Block layer zoned block device support. This option enables 106 support for ZAC/ZBC/ZNS host-managed and host-aware zoned block 107 devices. 108 109 Say yes here if you have a ZAC, ZBC, or ZNS storage device. 110 111config BLK_DEV_THROTTLING 112 bool "Block layer bio throttling support" 113 depends on BLK_CGROUP 114 select BLK_CGROUP_RWSTAT 115 help 116 Block layer bio throttling support. It can be used to limit 117 the IO rate to a device. IO rate policies are per cgroup and 118 one needs to mount and use blkio cgroup controller for creating 119 cgroups and specifying per device IO rate policies. 120 121 See Documentation/admin-guide/cgroup-v1/blkio-controller.rst for more information. 122 123config BLK_DEV_THROTTLING_LOW 124 bool "Block throttling .low limit interface support (EXPERIMENTAL)" 125 depends on BLK_DEV_THROTTLING 126 help 127 Add .low limit interface for block throttling. The low limit is a best 128 effort limit to prioritize cgroups. Depending on the setting, the limit 129 can be used to protect cgroups in terms of bandwidth/iops and better 130 utilize disk resource. 131 132 Note, this is an experimental interface and could be changed someday. 133 134config BLK_WBT 135 bool "Enable support for block device writeback throttling" 136 help 137 Enabling this option enables the block layer to throttle buffered 138 background writeback from the VM, making it more smooth and having 139 less impact on foreground operations. The throttling is done 140 dynamically on an algorithm loosely based on CoDel, factoring in 141 the realtime performance of the disk. 142 143config BLK_WBT_MQ 144 bool "Enable writeback throttling by default" 145 default y 146 depends on BLK_WBT 147 help 148 Enable writeback throttling by default for request-based block devices. 149 150config BLK_CGROUP_IOLATENCY 151 bool "Enable support for latency based cgroup IO protection" 152 depends on BLK_CGROUP 153 help 154 Enabling this option enables the .latency interface for IO throttling. 155 The IO controller will attempt to maintain average IO latencies below 156 the configured latency target, throttling anybody with a higher latency 157 target than the victimized group. 158 159 Note, this is an experimental interface and could be changed someday. 160 161config BLK_CGROUP_FC_APPID 162 bool "Enable support to track FC I/O Traffic across cgroup applications" 163 depends on BLK_CGROUP && NVME_FC 164 help 165 Enabling this option enables the support to track FC I/O traffic across 166 cgroup applications. It enables the Fabric and the storage targets to 167 identify, monitor, and handle FC traffic based on VM tags by inserting 168 application specific identification into the FC frame. 169 170config BLK_CGROUP_IOCOST 171 bool "Enable support for cost model based cgroup IO controller" 172 depends on BLK_CGROUP 173 select BLK_RQ_ALLOC_TIME 174 help 175 Enabling this option enables the .weight interface for cost 176 model based proportional IO control. The IO controller 177 distributes IO capacity between different groups based on 178 their share of the overall weight distribution. 179 180config BLK_CGROUP_IOPRIO 181 bool "Cgroup I/O controller for assigning an I/O priority class" 182 depends on BLK_CGROUP 183 help 184 Enable the .prio interface for assigning an I/O priority class to 185 requests. The I/O priority class affects the order in which an I/O 186 scheduler and block devices process requests. Only some I/O schedulers 187 and some block devices support I/O priorities. 188 189config BLK_DEBUG_FS 190 bool "Block layer debugging information in debugfs" 191 default y 192 depends on DEBUG_FS 193 help 194 Include block layer debugging information in debugfs. This information 195 is mostly useful for kernel developers, but it doesn't incur any cost 196 at runtime. 197 198 Unless you are building a kernel for a tiny system, you should 199 say Y here. 200 201config BLK_DEBUG_FS_ZONED 202 bool 203 default BLK_DEBUG_FS && BLK_DEV_ZONED 204 205config BLK_SED_OPAL 206 bool "Logic for interfacing with Opal enabled SEDs" 207 depends on KEYS 208 select PSERIES_PLPKS if PPC_PSERIES 209 select PSERIES_PLPKS_SED if PPC_PSERIES 210 help 211 Builds Logic for interfacing with Opal enabled controllers. 212 Enabling this option enables users to setup/unlock/lock 213 Locking ranges for SED devices using the Opal protocol. 214 215config BLK_INLINE_ENCRYPTION 216 bool "Enable inline encryption support in block layer" 217 help 218 Build the blk-crypto subsystem. Enabling this lets the 219 block layer handle encryption, so users can take 220 advantage of inline encryption hardware if present. 221 222config BLK_INLINE_ENCRYPTION_FALLBACK 223 bool "Enable crypto API fallback for blk-crypto" 224 depends on BLK_INLINE_ENCRYPTION 225 select CRYPTO 226 select CRYPTO_SKCIPHER 227 help 228 Enabling this lets the block layer handle inline encryption 229 by falling back to the kernel crypto API when inline 230 encryption hardware is not present. 231 232source "block/partitions/Kconfig" 233 234config BLK_MQ_PCI 235 def_bool PCI 236 237config BLK_MQ_VIRTIO 238 bool 239 depends on VIRTIO 240 default y 241 242config BLK_PM 243 def_bool PM 244 245# do not use in new code 246config BLOCK_HOLDER_DEPRECATED 247 bool 248 249config BLK_MQ_STACKING 250 bool 251 252source "block/Kconfig.iosched" 253 254endif # BLOCK 255