13a65dfe8SJens Axboe# 23a65dfe8SJens Axboe# Block layer core configuration 33a65dfe8SJens Axboe# 416ed002fSJan Engelhardtmenuconfig BLOCK 56a108a14SDavid Rientjes bool "Enable the block layer" if EXPERT 69361401eSDavid Howells default y 788459642SOmar Sandoval select SBITMAP 86a83e74dSBart Van Assche select SRCU 99361401eSDavid Howells help 10ee86418dSNick Andrew Provide block layer support for the kernel. 119361401eSDavid Howells 12ee86418dSNick Andrew Disable this option to remove the block layer support from the 13ee86418dSNick Andrew kernel. This may be useful for embedded devices. 14ee86418dSNick Andrew 15ee86418dSNick Andrew If this option is disabled: 16ee86418dSNick Andrew 17ee86418dSNick Andrew - block device files will become unusable 18ee86418dSNick Andrew - some filesystems (such as ext3) will become unavailable. 19ee86418dSNick Andrew 20ee86418dSNick Andrew Also, SCSI character devices and USB storage will be disabled since 21ee86418dSNick Andrew they make use of various block layer definitions and facilities. 229361401eSDavid Howells 239361401eSDavid Howells Say Y here unless you know you really don't want to mount disks and 249361401eSDavid Howells suchlike. 259361401eSDavid Howells 269361401eSDavid Howellsif BLOCK 279361401eSDavid Howells 2890c699a9SBartlomiej Zolnierkiewiczconfig LBDAF 2990c699a9SBartlomiej Zolnierkiewicz bool "Support for large (2TB+) block devices and files" 30e6243863SMatthew Wilcox depends on !64BIT 31db29a6b4SBartlomiej Zolnierkiewicz default y 323a65dfe8SJens Axboe help 33b3a6ffe1SJens Axboe Enable block devices or files of size 2TB and larger. 34ee86418dSNick Andrew 35ee86418dSNick Andrew This option is required to support the full capacity of large 36ee86418dSNick Andrew (2TB+) block devices, including RAID, disk, Network Block Device, 37ee86418dSNick Andrew Logical Volume Manager (LVM) and loopback. 38ee86418dSNick Andrew 39b3a6ffe1SJens Axboe This option also enables support for single files larger than 40b3a6ffe1SJens Axboe 2TB. 41ee86418dSNick Andrew 424d783b09STheodore Ts'o The ext4 filesystem requires that this feature be enabled in 434d783b09STheodore Ts'o order to support filesystems that have the huge_file feature 44db29a6b4SBartlomiej Zolnierkiewicz enabled. Otherwise, it will refuse to mount in the read-write 45db29a6b4SBartlomiej Zolnierkiewicz mode any filesystems that use the huge_file feature, which is 46db29a6b4SBartlomiej Zolnierkiewicz enabled by default by mke2fs.ext4. 474d783b09STheodore Ts'o 48db29a6b4SBartlomiej Zolnierkiewicz The GFS2 filesystem also requires this feature. 49db29a6b4SBartlomiej Zolnierkiewicz 50db29a6b4SBartlomiej Zolnierkiewicz If unsure, say Y. 513a65dfe8SJens Axboe 52*72148aecSChristoph Hellwigconfig BLK_SCSI_REQUEST 53*72148aecSChristoph Hellwig bool 54*72148aecSChristoph Hellwig 553d6392cfSJens Axboeconfig BLK_DEV_BSG 5614d9fa35SJohn Stoffel bool "Block layer SG support v4" 5714d9fa35SJohn Stoffel default y 58*72148aecSChristoph Hellwig select BLK_SCSI_REQUEST 5914d9fa35SJohn Stoffel help 60319a7b7fSFUJITA Tomonori Saying Y here will enable generic SG (SCSI generic) v4 support 61319a7b7fSFUJITA Tomonori for any block device. 62319a7b7fSFUJITA Tomonori 63319a7b7fSFUJITA Tomonori Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4 64319a7b7fSFUJITA Tomonori can handle complicated SCSI commands: tagged variable length cdbs 65319a7b7fSFUJITA Tomonori with bidirectional data transfers and generic request/response 66319a7b7fSFUJITA Tomonori protocols (e.g. Task Management Functions and SMP in Serial 67319a7b7fSFUJITA Tomonori Attached SCSI). 683d6392cfSJens Axboe 6914d9fa35SJohn Stoffel This option is required by recent UDEV versions to properly 7014d9fa35SJohn Stoffel access device serial numbers, etc. 7114d9fa35SJohn Stoffel 7214d9fa35SJohn Stoffel If unsure, say Y. 73ee86418dSNick Andrew 74aa387cc8SMike Christieconfig BLK_DEV_BSGLIB 75aa387cc8SMike Christie bool "Block layer SG support v4 helper lib" 76aa387cc8SMike Christie default n 77aa387cc8SMike Christie select BLK_DEV_BSG 78*72148aecSChristoph Hellwig select BLK_SCSI_REQUEST 79aa387cc8SMike Christie help 80aa387cc8SMike Christie Subsystems will normally enable this if needed. Users will not 81aa387cc8SMike Christie normally need to manually enable this. 82aa387cc8SMike Christie 83aa387cc8SMike Christie If unsure, say N. 84aa387cc8SMike Christie 857ba1ba12SMartin K. Petersenconfig BLK_DEV_INTEGRITY 867ba1ba12SMartin K. Petersen bool "Block layer data integrity support" 872341c2f8SMartin K. Petersen select CRC_T10DIF if BLK_DEV_INTEGRITY 887ba1ba12SMartin K. Petersen ---help--- 897ba1ba12SMartin K. Petersen Some storage devices allow extra information to be 907ba1ba12SMartin K. Petersen stored/retrieved to help protect the data. The block layer 917ba1ba12SMartin K. Petersen data integrity option provides hooks which can be used by 927ba1ba12SMartin K. Petersen filesystems to ensure better data integrity. 937ba1ba12SMartin K. Petersen 947ba1ba12SMartin K. Petersen Say yes here if you have a storage device that provides the 957ba1ba12SMartin K. Petersen T10/SCSI Data Integrity Field or the T13/ATA External Path 967ba1ba12SMartin K. Petersen Protection. If in doubt, say N. 977ba1ba12SMartin K. Petersen 986a0cb1bcSHannes Reineckeconfig BLK_DEV_ZONED 996a0cb1bcSHannes Reinecke bool "Zoned block device support" 1006a0cb1bcSHannes Reinecke ---help--- 1016a0cb1bcSHannes Reinecke Block layer zoned block device support. This option enables 1026a0cb1bcSHannes Reinecke support for ZAC/ZBC host-managed and host-aware zoned block devices. 1036a0cb1bcSHannes Reinecke 1046a0cb1bcSHannes Reinecke Say yes here if you have a ZAC or ZBC storage device. 1056a0cb1bcSHannes Reinecke 106e43473b7SVivek Goyalconfig BLK_DEV_THROTTLING 107e43473b7SVivek Goyal bool "Block layer bio throttling support" 1088e42e0a2SKees Cook depends on BLK_CGROUP=y 109e43473b7SVivek Goyal default n 110e43473b7SVivek Goyal ---help--- 111e43473b7SVivek Goyal Block layer bio throttling support. It can be used to limit 112e43473b7SVivek Goyal the IO rate to a device. IO rate policies are per cgroup and 113e43473b7SVivek Goyal one needs to mount and use blkio cgroup controller for creating 114e43473b7SVivek Goyal cgroups and specifying per device IO rate policies. 115e43473b7SVivek Goyal 116e43473b7SVivek Goyal See Documentation/cgroups/blkio-controller.txt for more information. 117e43473b7SVivek Goyal 118080506adSPaul Gortmakerconfig BLK_CMDLINE_PARSER 119bab55417SCai Zhiyong bool "Block device command line partition parser" 120bab55417SCai Zhiyong default n 121bab55417SCai Zhiyong ---help--- 122080506adSPaul Gortmaker Enabling this option allows you to specify the partition layout from 123080506adSPaul Gortmaker the kernel boot args. This is typically of use for embedded devices 124080506adSPaul Gortmaker which don't otherwise have any standardized method for listing the 125080506adSPaul Gortmaker partitions on a block device. 126080506adSPaul Gortmaker 127080506adSPaul Gortmaker See Documentation/block/cmdline-partition.txt for more information. 128bab55417SCai Zhiyong 12987760e5eSJens Axboeconfig BLK_WBT 13087760e5eSJens Axboe bool "Enable support for block device writeback throttling" 13187760e5eSJens Axboe default n 13287760e5eSJens Axboe ---help--- 13387760e5eSJens Axboe Enabling this option enables the block layer to throttle buffered 13487760e5eSJens Axboe background writeback from the VM, making it more smooth and having 13587760e5eSJens Axboe less impact on foreground operations. The throttling is done 13687760e5eSJens Axboe dynamically on an algorithm loosely based on CoDel, factoring in 13787760e5eSJens Axboe the realtime performance of the disk. 13887760e5eSJens Axboe 13987760e5eSJens Axboeconfig BLK_WBT_SQ 14087760e5eSJens Axboe bool "Single queue writeback throttling" 14187760e5eSJens Axboe default n 14287760e5eSJens Axboe depends on BLK_WBT 14387760e5eSJens Axboe ---help--- 14487760e5eSJens Axboe Enable writeback throttling by default on legacy single queue devices 14587760e5eSJens Axboe 14687760e5eSJens Axboeconfig BLK_WBT_MQ 14787760e5eSJens Axboe bool "Multiqueue writeback throttling" 14887760e5eSJens Axboe default y 14987760e5eSJens Axboe depends on BLK_WBT 15087760e5eSJens Axboe ---help--- 15187760e5eSJens Axboe Enable writeback throttling by default on multiqueue devices. 15287760e5eSJens Axboe Multiqueue currently doesn't have support for IO scheduling, 15387760e5eSJens Axboe enabling this option is recommended. 15487760e5eSJens Axboe 155400f73b2SOmar Sandovalconfig BLK_DEBUG_FS 156400f73b2SOmar Sandoval bool "Block layer debugging information in debugfs" 157400f73b2SOmar Sandoval default y 158400f73b2SOmar Sandoval depends on DEBUG_FS 159400f73b2SOmar Sandoval ---help--- 160400f73b2SOmar Sandoval Include block layer debugging information in debugfs. This information 161400f73b2SOmar Sandoval is mostly useful for kernel developers, but it doesn't incur any cost 162400f73b2SOmar Sandoval at runtime. 163400f73b2SOmar Sandoval 164400f73b2SOmar Sandoval Unless you are building a kernel for a tiny system, you should 165400f73b2SOmar Sandoval say Y here. 166400f73b2SOmar Sandoval 1679be96f3fSAl Viromenu "Partition Types" 1689be96f3fSAl Viro 1699be96f3fSAl Virosource "block/partitions/Kconfig" 1709be96f3fSAl Viro 1719be96f3fSAl Viroendmenu 1729be96f3fSAl Viro 1732b9e0aaeSLinus Torvaldsendif # BLOCK 1742b9e0aaeSLinus Torvalds 17599874d50SJens Axboeconfig BLOCK_COMPAT 17699874d50SJens Axboe bool 1772b9e0aaeSLinus Torvalds depends on BLOCK && COMPAT 17899874d50SJens Axboe default y 17999874d50SJens Axboe 1808ec2ef2bSStephen Rothwellconfig BLK_MQ_PCI 1818ec2ef2bSStephen Rothwell bool 1828ec2ef2bSStephen Rothwell depends on BLOCK && PCI 1838ec2ef2bSStephen Rothwell default y 1848ec2ef2bSStephen Rothwell 1853a65dfe8SJens Axboesource block/Kconfig.iosched 186