| 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 FS_IOMAP |
| 9 | select SBITMAP |
| 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 BLOCK_LEGACY_AUTOLOAD |
| 30 | bool "Legacy autoloading support" |
| 31 | default y |
| 32 | help |
| 33 | Enable loading modules and creating block device instances based on |
| 34 | accesses through their device special file. This is a historic Linux |
| 35 | feature and makes no sense in a udev world where device files are |
| 36 | created on demand, but scripts that manually create device nodes and |
| 37 | then call losetup might rely on this behavior. |
| 38 | |
| 39 | config BLK_RQ_ALLOC_TIME |
| 40 | bool |
| 41 | |
| 42 | config BLK_CGROUP_RWSTAT |
| 43 | bool |
| 44 | |
| 45 | config BLK_CGROUP_PUNT_BIO |
| 46 | bool |
| 47 | |
| 48 | config BLK_DEV_BSG_COMMON |
| 49 | tristate |
| 50 | |
| 51 | config BLK_ICQ |
| 52 | bool |
| 53 | |
| 54 | config BLK_DEV_BSGLIB |
| 55 | bool "Block layer SG support v4 helper lib" |
| 56 | select BLK_DEV_BSG_COMMON |
| 57 | help |
| 58 | Subsystems will normally enable this if needed. Users will not |
| 59 | normally need to manually enable this. |
| 60 | |
| 61 | If unsure, say N. |
| 62 | |
| 63 | config BLK_DEV_INTEGRITY |
| 64 | bool "Block layer data integrity support" |
| 65 | help |
| 66 | Some storage devices allow extra information to be |
| 67 | stored/retrieved to help protect the data. The block layer |
| 68 | data integrity option provides hooks which can be used by |
| 69 | filesystems to ensure better data integrity. |
| 70 | |
| 71 | Say yes here if you have a storage device that provides the |
| 72 | T10/SCSI Data Integrity Field or the T13/ATA External Path |
| 73 | Protection. If in doubt, say N. |
| 74 | |
| 75 | config BLK_DEV_INTEGRITY_T10 |
| 76 | tristate |
| 77 | depends on BLK_DEV_INTEGRITY |
| 78 | select CRC_T10DIF |
| 79 | select CRC64_ROCKSOFT |
| 80 | |
| 81 | config 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 | |
| 101 | config 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 | |
| 111 | config 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 | |
| 123 | config 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 | |
| 134 | config 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 | |
| 143 | config 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 | |
| 150 | config 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 | |
| 161 | config 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 | |
| 170 | config 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 | |
| 180 | config 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 | |
| 189 | config 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 | |
| 201 | config BLK_DEBUG_FS_ZONED |
| 202 | bool |
| 203 | default BLK_DEBUG_FS && BLK_DEV_ZONED |
| 204 | |
| 205 | config 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 | |
| 215 | config 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 | |
| 222 | config 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 | |
| 232 | source "block/partitions/Kconfig" |
| 233 | |
| 234 | config BLK_MQ_PCI |
| 235 | def_bool PCI |
| 236 | |
| 237 | config BLK_MQ_VIRTIO |
| 238 | bool |
| 239 | depends on VIRTIO |
| 240 | default y |
| 241 | |
| 242 | config BLK_PM |
| 243 | def_bool PM |
| 244 | |
| 245 | # do not use in new code |
| 246 | config BLOCK_HOLDER_DEPRECATED |
| 247 | bool |
| 248 | |
| 249 | config BLK_MQ_STACKING |
| 250 | bool |
| 251 | |
| 252 | source "block/Kconfig.iosched" |
| 253 | |
| 254 | endif # BLOCK |