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 7*88459642SOmar Sandoval select SBITMAP 89361401eSDavid Howells help 9ee86418dSNick Andrew Provide block layer support for the kernel. 109361401eSDavid Howells 11ee86418dSNick Andrew Disable this option to remove the block layer support from the 12ee86418dSNick Andrew kernel. This may be useful for embedded devices. 13ee86418dSNick Andrew 14ee86418dSNick Andrew If this option is disabled: 15ee86418dSNick Andrew 16ee86418dSNick Andrew - block device files will become unusable 17ee86418dSNick Andrew - some filesystems (such as ext3) will become unavailable. 18ee86418dSNick Andrew 19ee86418dSNick Andrew Also, SCSI character devices and USB storage will be disabled since 20ee86418dSNick Andrew they make use of various block layer definitions and facilities. 219361401eSDavid Howells 229361401eSDavid Howells Say Y here unless you know you really don't want to mount disks and 239361401eSDavid Howells suchlike. 249361401eSDavid Howells 259361401eSDavid Howellsif BLOCK 269361401eSDavid Howells 2790c699a9SBartlomiej Zolnierkiewiczconfig LBDAF 2890c699a9SBartlomiej Zolnierkiewicz bool "Support for large (2TB+) block devices and files" 29e6243863SMatthew Wilcox depends on !64BIT 30db29a6b4SBartlomiej Zolnierkiewicz default y 313a65dfe8SJens Axboe help 32b3a6ffe1SJens Axboe Enable block devices or files of size 2TB and larger. 33ee86418dSNick Andrew 34ee86418dSNick Andrew This option is required to support the full capacity of large 35ee86418dSNick Andrew (2TB+) block devices, including RAID, disk, Network Block Device, 36ee86418dSNick Andrew Logical Volume Manager (LVM) and loopback. 37ee86418dSNick Andrew 38b3a6ffe1SJens Axboe This option also enables support for single files larger than 39b3a6ffe1SJens Axboe 2TB. 40ee86418dSNick Andrew 414d783b09STheodore Ts'o The ext4 filesystem requires that this feature be enabled in 424d783b09STheodore Ts'o order to support filesystems that have the huge_file feature 43db29a6b4SBartlomiej Zolnierkiewicz enabled. Otherwise, it will refuse to mount in the read-write 44db29a6b4SBartlomiej Zolnierkiewicz mode any filesystems that use the huge_file feature, which is 45db29a6b4SBartlomiej Zolnierkiewicz enabled by default by mke2fs.ext4. 464d783b09STheodore Ts'o 47db29a6b4SBartlomiej Zolnierkiewicz The GFS2 filesystem also requires this feature. 48db29a6b4SBartlomiej Zolnierkiewicz 49db29a6b4SBartlomiej Zolnierkiewicz If unsure, say Y. 503a65dfe8SJens Axboe 513d6392cfSJens Axboeconfig BLK_DEV_BSG 5214d9fa35SJohn Stoffel bool "Block layer SG support v4" 5314d9fa35SJohn Stoffel default y 5414d9fa35SJohn Stoffel help 55319a7b7fSFUJITA Tomonori Saying Y here will enable generic SG (SCSI generic) v4 support 56319a7b7fSFUJITA Tomonori for any block device. 57319a7b7fSFUJITA Tomonori 58319a7b7fSFUJITA Tomonori Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4 59319a7b7fSFUJITA Tomonori can handle complicated SCSI commands: tagged variable length cdbs 60319a7b7fSFUJITA Tomonori with bidirectional data transfers and generic request/response 61319a7b7fSFUJITA Tomonori protocols (e.g. Task Management Functions and SMP in Serial 62319a7b7fSFUJITA Tomonori Attached SCSI). 633d6392cfSJens Axboe 6414d9fa35SJohn Stoffel This option is required by recent UDEV versions to properly 6514d9fa35SJohn Stoffel access device serial numbers, etc. 6614d9fa35SJohn Stoffel 6714d9fa35SJohn Stoffel If unsure, say Y. 68ee86418dSNick Andrew 69aa387cc8SMike Christieconfig BLK_DEV_BSGLIB 70aa387cc8SMike Christie bool "Block layer SG support v4 helper lib" 71aa387cc8SMike Christie default n 72aa387cc8SMike Christie select BLK_DEV_BSG 73aa387cc8SMike Christie help 74aa387cc8SMike Christie Subsystems will normally enable this if needed. Users will not 75aa387cc8SMike Christie normally need to manually enable this. 76aa387cc8SMike Christie 77aa387cc8SMike Christie If unsure, say N. 78aa387cc8SMike Christie 797ba1ba12SMartin K. Petersenconfig BLK_DEV_INTEGRITY 807ba1ba12SMartin K. Petersen bool "Block layer data integrity support" 812341c2f8SMartin K. Petersen select CRC_T10DIF if BLK_DEV_INTEGRITY 827ba1ba12SMartin K. Petersen ---help--- 837ba1ba12SMartin K. Petersen Some storage devices allow extra information to be 847ba1ba12SMartin K. Petersen stored/retrieved to help protect the data. The block layer 857ba1ba12SMartin K. Petersen data integrity option provides hooks which can be used by 867ba1ba12SMartin K. Petersen filesystems to ensure better data integrity. 877ba1ba12SMartin K. Petersen 887ba1ba12SMartin K. Petersen Say yes here if you have a storage device that provides the 897ba1ba12SMartin K. Petersen T10/SCSI Data Integrity Field or the T13/ATA External Path 907ba1ba12SMartin K. Petersen Protection. If in doubt, say N. 917ba1ba12SMartin K. Petersen 92e43473b7SVivek Goyalconfig BLK_DEV_THROTTLING 93e43473b7SVivek Goyal bool "Block layer bio throttling support" 948e42e0a2SKees Cook depends on BLK_CGROUP=y 95e43473b7SVivek Goyal default n 96e43473b7SVivek Goyal ---help--- 97e43473b7SVivek Goyal Block layer bio throttling support. It can be used to limit 98e43473b7SVivek Goyal the IO rate to a device. IO rate policies are per cgroup and 99e43473b7SVivek Goyal one needs to mount and use blkio cgroup controller for creating 100e43473b7SVivek Goyal cgroups and specifying per device IO rate policies. 101e43473b7SVivek Goyal 102e43473b7SVivek Goyal See Documentation/cgroups/blkio-controller.txt for more information. 103e43473b7SVivek Goyal 104080506adSPaul Gortmakerconfig BLK_CMDLINE_PARSER 105bab55417SCai Zhiyong bool "Block device command line partition parser" 106bab55417SCai Zhiyong default n 107bab55417SCai Zhiyong ---help--- 108080506adSPaul Gortmaker Enabling this option allows you to specify the partition layout from 109080506adSPaul Gortmaker the kernel boot args. This is typically of use for embedded devices 110080506adSPaul Gortmaker which don't otherwise have any standardized method for listing the 111080506adSPaul Gortmaker partitions on a block device. 112080506adSPaul Gortmaker 113080506adSPaul Gortmaker See Documentation/block/cmdline-partition.txt for more information. 114bab55417SCai Zhiyong 1159be96f3fSAl Viromenu "Partition Types" 1169be96f3fSAl Viro 1179be96f3fSAl Virosource "block/partitions/Kconfig" 1189be96f3fSAl Viro 1199be96f3fSAl Viroendmenu 1209be96f3fSAl Viro 1212b9e0aaeSLinus Torvaldsendif # BLOCK 1222b9e0aaeSLinus Torvalds 12399874d50SJens Axboeconfig BLOCK_COMPAT 12499874d50SJens Axboe bool 1252b9e0aaeSLinus Torvalds depends on BLOCK && COMPAT 12699874d50SJens Axboe default y 12799874d50SJens Axboe 1283a65dfe8SJens Axboesource block/Kconfig.iosched 129