1 # SPDX-License-Identifier: GPL-2.0 1 # SPDX-License-Identifier: GPL-2.0
2 # 2 #
3 # Block layer core configuration 3 # Block layer core configuration
4 # 4 #
5 menuconfig BLOCK 5 menuconfig BLOCK
6 bool "Enable the block layer" if EXPERT 6 bool "Enable the block layer" if EXPERT
7 default y 7 default y
8 select FS_IOMAP 8 select FS_IOMAP
9 select SBITMAP 9 select SBITMAP
10 help 10 help
11 Provide block layer support for the k 11 Provide block layer support for the kernel.
12 12
13 Disable this option to remove the blo 13 Disable this option to remove the block layer support from the
14 kernel. This may be useful for embedd 14 kernel. This may be useful for embedded devices.
15 15
16 If this option is disabled: 16 If this option is disabled:
17 17
18 - block device files will become un 18 - block device files will become unusable
19 - some filesystems (such as ext3) w 19 - some filesystems (such as ext3) will become unavailable.
20 20
21 Also, SCSI character devices and USB 21 Also, SCSI character devices and USB storage will be disabled since
22 they make use of various block layer 22 they make use of various block layer definitions and facilities.
23 23
24 Say Y here unless you know you really 24 Say Y here unless you know you really don't want to mount disks and
25 suchlike. 25 suchlike.
26 26
27 if BLOCK 27 if BLOCK
28 28
29 config BLOCK_LEGACY_AUTOLOAD 29 config BLOCK_LEGACY_AUTOLOAD
30 bool "Legacy autoloading support" 30 bool "Legacy autoloading support"
31 default y 31 default y
32 help 32 help
33 Enable loading modules and creating 33 Enable loading modules and creating block device instances based on
34 accesses through their device specia 34 accesses through their device special file. This is a historic Linux
35 feature and makes no sense in a udev 35 feature and makes no sense in a udev world where device files are
36 created on demand, but scripts that 36 created on demand, but scripts that manually create device nodes and
37 then call losetup might rely on this 37 then call losetup might rely on this behavior.
38 38
39 config BLK_RQ_ALLOC_TIME 39 config BLK_RQ_ALLOC_TIME
40 bool 40 bool
41 41
42 config BLK_CGROUP_RWSTAT 42 config BLK_CGROUP_RWSTAT
43 bool 43 bool
44 44
45 config BLK_CGROUP_PUNT_BIO 45 config BLK_CGROUP_PUNT_BIO
46 bool 46 bool
47 47
48 config BLK_DEV_BSG_COMMON 48 config BLK_DEV_BSG_COMMON
49 tristate 49 tristate
50 50
51 config BLK_ICQ 51 config BLK_ICQ
52 bool 52 bool
53 53
54 config BLK_DEV_BSGLIB 54 config BLK_DEV_BSGLIB
55 bool "Block layer SG support v4 helper 55 bool "Block layer SG support v4 helper lib"
56 select BLK_DEV_BSG_COMMON 56 select BLK_DEV_BSG_COMMON
57 help 57 help
58 Subsystems will normally enable this 58 Subsystems will normally enable this if needed. Users will not
59 normally need to manually enable thi 59 normally need to manually enable this.
60 60
61 If unsure, say N. 61 If unsure, say N.
62 62
63 config BLK_DEV_INTEGRITY 63 config BLK_DEV_INTEGRITY
64 bool "Block layer data integrity suppo 64 bool "Block layer data integrity support"
65 select CRC_T10DIF 65 select CRC_T10DIF
66 select CRC64_ROCKSOFT 66 select CRC64_ROCKSOFT
67 help 67 help
68 Some storage devices allow extra infor 68 Some storage devices allow extra information to be
69 stored/retrieved to help protect the d 69 stored/retrieved to help protect the data. The block layer
70 data integrity option provides hooks w 70 data integrity option provides hooks which can be used by
71 filesystems to ensure better data inte 71 filesystems to ensure better data integrity.
72 72
73 Say yes here if you have a storage dev 73 Say yes here if you have a storage device that provides the
74 T10/SCSI Data Integrity Field or the T 74 T10/SCSI Data Integrity Field or the T13/ATA External Path
75 Protection. If in doubt, say N. 75 Protection. If in doubt, say N.
76 76
77 config BLK_DEV_WRITE_MOUNTED 77 config BLK_DEV_WRITE_MOUNTED
78 bool "Allow writing to mounted block d 78 bool "Allow writing to mounted block devices"
79 default y 79 default y
80 help 80 help
81 When a block device is mounted, writin 81 When a block device is mounted, writing to its buffer cache is very
82 likely going to cause filesystem corru 82 likely going to cause filesystem corruption. It is also rather easy to
83 crash the kernel in this way since the 83 crash the kernel in this way since the filesystem has no practical way
84 of detecting these writes to buffer ca 84 of detecting these writes to buffer cache and verifying its metadata
85 integrity. However there are some setu 85 integrity. However there are some setups that need this capability
86 like running fsck on read-only mounted 86 like running fsck on read-only mounted root device, modifying some
87 features on mounted ext4 filesystem, a 87 features on mounted ext4 filesystem, and similar. If you say N, the
88 kernel will prevent processes from wri 88 kernel will prevent processes from writing to block devices that are
89 mounted by filesystems which provides 89 mounted by filesystems which provides some more protection from runaway
90 privileged processes and generally mak 90 privileged processes and generally makes it much harder to crash
91 filesystem drivers. Note however that 91 filesystem drivers. Note however that this does not prevent
92 underlying device(s) from being modifi 92 underlying device(s) from being modified by other means, e.g. by
93 directly submitting SCSI commands or t 93 directly submitting SCSI commands or through access to lower layers of
94 storage stack. If in doubt, say Y. The 94 storage stack. If in doubt, say Y. The configuration can be overridden
95 with the bdev_allow_write_mounted boot 95 with the bdev_allow_write_mounted boot option.
96 96
97 config BLK_DEV_ZONED 97 config BLK_DEV_ZONED
98 bool "Zoned block device support" 98 bool "Zoned block device support"
99 help 99 help
100 Block layer zoned block device support 100 Block layer zoned block device support. This option enables
101 support for ZAC/ZBC/ZNS host-managed a 101 support for ZAC/ZBC/ZNS host-managed and host-aware zoned block
102 devices. 102 devices.
103 103
104 Say yes here if you have a ZAC, ZBC, o 104 Say yes here if you have a ZAC, ZBC, or ZNS storage device.
105 105
106 config BLK_DEV_THROTTLING 106 config BLK_DEV_THROTTLING
107 bool "Block layer bio throttling suppo 107 bool "Block layer bio throttling support"
108 depends on BLK_CGROUP 108 depends on BLK_CGROUP
109 select BLK_CGROUP_RWSTAT 109 select BLK_CGROUP_RWSTAT
110 help 110 help
111 Block layer bio throttling support. It 111 Block layer bio throttling support. It can be used to limit
112 the IO rate to a device. IO rate polic 112 the IO rate to a device. IO rate policies are per cgroup and
113 one needs to mount and use blkio cgrou 113 one needs to mount and use blkio cgroup controller for creating
114 cgroups and specifying per device IO r 114 cgroups and specifying per device IO rate policies.
115 115
116 See Documentation/admin-guide/cgroup-v 116 See Documentation/admin-guide/cgroup-v1/blkio-controller.rst for more information.
117 117
118 config BLK_WBT 118 config BLK_WBT
119 bool "Enable support for block device 119 bool "Enable support for block device writeback throttling"
120 help 120 help
121 Enabling this option enables the block 121 Enabling this option enables the block layer to throttle buffered
122 background writeback from the VM, maki 122 background writeback from the VM, making it more smooth and having
123 less impact on foreground operations. 123 less impact on foreground operations. The throttling is done
124 dynamically on an algorithm loosely ba 124 dynamically on an algorithm loosely based on CoDel, factoring in
125 the realtime performance of the disk. 125 the realtime performance of the disk.
126 126
127 config BLK_WBT_MQ 127 config BLK_WBT_MQ
128 bool "Enable writeback throttling by d 128 bool "Enable writeback throttling by default"
129 default y 129 default y
130 depends on BLK_WBT 130 depends on BLK_WBT
131 help 131 help
132 Enable writeback throttling by default 132 Enable writeback throttling by default for request-based block devices.
133 133
134 config BLK_CGROUP_IOLATENCY 134 config BLK_CGROUP_IOLATENCY
135 bool "Enable support for latency based 135 bool "Enable support for latency based cgroup IO protection"
136 depends on BLK_CGROUP 136 depends on BLK_CGROUP
137 help 137 help
138 Enabling this option enables the .late 138 Enabling this option enables the .latency interface for IO throttling.
139 The IO controller will attempt to main 139 The IO controller will attempt to maintain average IO latencies below
140 the configured latency target, throttl 140 the configured latency target, throttling anybody with a higher latency
141 target than the victimized group. 141 target than the victimized group.
142 142
143 Note, this is an experimental interfac 143 Note, this is an experimental interface and could be changed someday.
144 144
145 config BLK_CGROUP_FC_APPID 145 config BLK_CGROUP_FC_APPID
146 bool "Enable support to track FC I/O T 146 bool "Enable support to track FC I/O Traffic across cgroup applications"
147 depends on BLK_CGROUP && NVME_FC 147 depends on BLK_CGROUP && NVME_FC
148 help 148 help
149 Enabling this option enables the sup 149 Enabling this option enables the support to track FC I/O traffic across
150 cgroup applications. It enables the 150 cgroup applications. It enables the Fabric and the storage targets to
151 identify, monitor, and handle FC tra 151 identify, monitor, and handle FC traffic based on VM tags by inserting
152 application specific identification 152 application specific identification into the FC frame.
153 153
154 config BLK_CGROUP_IOCOST 154 config BLK_CGROUP_IOCOST
155 bool "Enable support for cost model ba 155 bool "Enable support for cost model based cgroup IO controller"
156 depends on BLK_CGROUP 156 depends on BLK_CGROUP
157 select BLK_RQ_ALLOC_TIME 157 select BLK_RQ_ALLOC_TIME
158 help 158 help
159 Enabling this option enables the .weig 159 Enabling this option enables the .weight interface for cost
160 model based proportional IO control. 160 model based proportional IO control. The IO controller
161 distributes IO capacity between differ 161 distributes IO capacity between different groups based on
162 their share of the overall weight dist 162 their share of the overall weight distribution.
163 163
164 config BLK_CGROUP_IOPRIO 164 config BLK_CGROUP_IOPRIO
165 bool "Cgroup I/O controller for assign 165 bool "Cgroup I/O controller for assigning an I/O priority class"
166 depends on BLK_CGROUP 166 depends on BLK_CGROUP
167 help 167 help
168 Enable the .prio interface for assigni 168 Enable the .prio interface for assigning an I/O priority class to
169 requests. The I/O priority class affec 169 requests. The I/O priority class affects the order in which an I/O
170 scheduler and block devices process re 170 scheduler and block devices process requests. Only some I/O schedulers
171 and some block devices support I/O pri 171 and some block devices support I/O priorities.
172 172
173 config BLK_DEBUG_FS 173 config BLK_DEBUG_FS
174 bool "Block layer debugging informatio 174 bool "Block layer debugging information in debugfs"
175 default y 175 default y
176 depends on DEBUG_FS 176 depends on DEBUG_FS
177 help 177 help
178 Include block layer debugging informat 178 Include block layer debugging information in debugfs. This information
179 is mostly useful for kernel developers 179 is mostly useful for kernel developers, but it doesn't incur any cost
180 at runtime. 180 at runtime.
181 181
182 Unless you are building a kernel for a 182 Unless you are building a kernel for a tiny system, you should
183 say Y here. 183 say Y here.
184 184
185 config BLK_SED_OPAL 185 config BLK_SED_OPAL
186 bool "Logic for interfacing with Opal 186 bool "Logic for interfacing with Opal enabled SEDs"
187 depends on KEYS 187 depends on KEYS
188 select PSERIES_PLPKS if PPC_PSERIES 188 select PSERIES_PLPKS if PPC_PSERIES
189 select PSERIES_PLPKS_SED if PPC_PSERIE 189 select PSERIES_PLPKS_SED if PPC_PSERIES
190 help 190 help
191 Builds Logic for interfacing with Opal 191 Builds Logic for interfacing with Opal enabled controllers.
192 Enabling this option enables users to 192 Enabling this option enables users to setup/unlock/lock
193 Locking ranges for SED devices using t 193 Locking ranges for SED devices using the Opal protocol.
194 194
195 config BLK_INLINE_ENCRYPTION 195 config BLK_INLINE_ENCRYPTION
196 bool "Enable inline encryption support 196 bool "Enable inline encryption support in block layer"
197 help 197 help
198 Build the blk-crypto subsystem. Enab 198 Build the blk-crypto subsystem. Enabling this lets the
199 block layer handle encryption, so us 199 block layer handle encryption, so users can take
200 advantage of inline encryption hardw 200 advantage of inline encryption hardware if present.
201 201
202 config BLK_INLINE_ENCRYPTION_FALLBACK 202 config BLK_INLINE_ENCRYPTION_FALLBACK
203 bool "Enable crypto API fallback for b 203 bool "Enable crypto API fallback for blk-crypto"
204 depends on BLK_INLINE_ENCRYPTION 204 depends on BLK_INLINE_ENCRYPTION
205 select CRYPTO 205 select CRYPTO
206 select CRYPTO_SKCIPHER 206 select CRYPTO_SKCIPHER
207 help 207 help
208 Enabling this lets the block layer h 208 Enabling this lets the block layer handle inline encryption
209 by falling back to the kernel crypto 209 by falling back to the kernel crypto API when inline
210 encryption hardware is not present. 210 encryption hardware is not present.
211 211
212 source "block/partitions/Kconfig" 212 source "block/partitions/Kconfig"
213 213
214 config BLK_MQ_PCI 214 config BLK_MQ_PCI
215 def_bool PCI 215 def_bool PCI
216 216
217 config BLK_MQ_VIRTIO 217 config BLK_MQ_VIRTIO
218 bool 218 bool
219 depends on VIRTIO 219 depends on VIRTIO
220 default y 220 default y
221 221
222 config BLK_PM 222 config BLK_PM
223 def_bool PM 223 def_bool PM
224 224
225 # do not use in new code 225 # do not use in new code
226 config BLOCK_HOLDER_DEPRECATED 226 config BLOCK_HOLDER_DEPRECATED
227 bool 227 bool
228 228
229 config BLK_MQ_STACKING 229 config BLK_MQ_STACKING
230 bool 230 bool
231 231
232 source "block/Kconfig.iosched" 232 source "block/Kconfig.iosched"
233 233
234 endif # BLOCK 234 endif # BLOCK
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