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 79361401eSDavid Howells help 8ee86418dSNick Andrew Provide block layer support for the kernel. 99361401eSDavid Howells 10ee86418dSNick Andrew Disable this option to remove the block layer support from the 11ee86418dSNick Andrew kernel. This may be useful for embedded devices. 12ee86418dSNick Andrew 13ee86418dSNick Andrew If this option is disabled: 14ee86418dSNick Andrew 15ee86418dSNick Andrew - block device files will become unusable 16ee86418dSNick Andrew - some filesystems (such as ext3) will become unavailable. 17ee86418dSNick Andrew 18ee86418dSNick Andrew Also, SCSI character devices and USB storage will be disabled since 19ee86418dSNick Andrew they make use of various block layer definitions and facilities. 209361401eSDavid Howells 219361401eSDavid Howells Say Y here unless you know you really don't want to mount disks and 229361401eSDavid Howells suchlike. 239361401eSDavid Howells 249361401eSDavid Howellsif BLOCK 259361401eSDavid Howells 2690c699a9SBartlomiej Zolnierkiewiczconfig LBDAF 2790c699a9SBartlomiej Zolnierkiewicz bool "Support for large (2TB+) block devices and files" 28e6243863SMatthew Wilcox depends on !64BIT 29db29a6b4SBartlomiej Zolnierkiewicz default y 303a65dfe8SJens Axboe help 31b3a6ffe1SJens Axboe Enable block devices or files of size 2TB and larger. 32ee86418dSNick Andrew 33ee86418dSNick Andrew This option is required to support the full capacity of large 34ee86418dSNick Andrew (2TB+) block devices, including RAID, disk, Network Block Device, 35ee86418dSNick Andrew Logical Volume Manager (LVM) and loopback. 36ee86418dSNick Andrew 37b3a6ffe1SJens Axboe This option also enables support for single files larger than 38b3a6ffe1SJens Axboe 2TB. 39ee86418dSNick Andrew 404d783b09STheodore Ts'o The ext4 filesystem requires that this feature be enabled in 414d783b09STheodore Ts'o order to support filesystems that have the huge_file feature 42db29a6b4SBartlomiej Zolnierkiewicz enabled. Otherwise, it will refuse to mount in the read-write 43db29a6b4SBartlomiej Zolnierkiewicz mode any filesystems that use the huge_file feature, which is 44db29a6b4SBartlomiej Zolnierkiewicz enabled by default by mke2fs.ext4. 454d783b09STheodore Ts'o 46db29a6b4SBartlomiej Zolnierkiewicz The GFS2 filesystem also requires this feature. 47db29a6b4SBartlomiej Zolnierkiewicz 48db29a6b4SBartlomiej Zolnierkiewicz If unsure, say Y. 493a65dfe8SJens Axboe 503d6392cfSJens Axboeconfig BLK_DEV_BSG 5114d9fa35SJohn Stoffel bool "Block layer SG support v4" 5214d9fa35SJohn Stoffel default y 5314d9fa35SJohn Stoffel help 54319a7b7fSFUJITA Tomonori Saying Y here will enable generic SG (SCSI generic) v4 support 55319a7b7fSFUJITA Tomonori for any block device. 56319a7b7fSFUJITA Tomonori 57319a7b7fSFUJITA Tomonori Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4 58319a7b7fSFUJITA Tomonori can handle complicated SCSI commands: tagged variable length cdbs 59319a7b7fSFUJITA Tomonori with bidirectional data transfers and generic request/response 60319a7b7fSFUJITA Tomonori protocols (e.g. Task Management Functions and SMP in Serial 61319a7b7fSFUJITA Tomonori Attached SCSI). 623d6392cfSJens Axboe 6314d9fa35SJohn Stoffel This option is required by recent UDEV versions to properly 6414d9fa35SJohn Stoffel access device serial numbers, etc. 6514d9fa35SJohn Stoffel 6614d9fa35SJohn Stoffel If unsure, say Y. 67ee86418dSNick Andrew 68aa387cc8SMike Christieconfig BLK_DEV_BSGLIB 69aa387cc8SMike Christie bool "Block layer SG support v4 helper lib" 70aa387cc8SMike Christie default n 71aa387cc8SMike Christie select BLK_DEV_BSG 72aa387cc8SMike Christie help 73aa387cc8SMike Christie Subsystems will normally enable this if needed. Users will not 74aa387cc8SMike Christie normally need to manually enable this. 75aa387cc8SMike Christie 76aa387cc8SMike Christie If unsure, say N. 77aa387cc8SMike Christie 787ba1ba12SMartin K. Petersenconfig BLK_DEV_INTEGRITY 797ba1ba12SMartin K. Petersen bool "Block layer data integrity support" 802341c2f8SMartin K. Petersen select CRC_T10DIF if BLK_DEV_INTEGRITY 817ba1ba12SMartin K. Petersen ---help--- 827ba1ba12SMartin K. Petersen Some storage devices allow extra information to be 837ba1ba12SMartin K. Petersen stored/retrieved to help protect the data. The block layer 847ba1ba12SMartin K. Petersen data integrity option provides hooks which can be used by 857ba1ba12SMartin K. Petersen filesystems to ensure better data integrity. 867ba1ba12SMartin K. Petersen 877ba1ba12SMartin K. Petersen Say yes here if you have a storage device that provides the 887ba1ba12SMartin K. Petersen T10/SCSI Data Integrity Field or the T13/ATA External Path 897ba1ba12SMartin K. Petersen Protection. If in doubt, say N. 907ba1ba12SMartin K. Petersen 91e43473b7SVivek Goyalconfig BLK_DEV_THROTTLING 92e43473b7SVivek Goyal bool "Block layer bio throttling support" 938e42e0a2SKees Cook depends on BLK_CGROUP=y 94e43473b7SVivek Goyal default n 95e43473b7SVivek Goyal ---help--- 96e43473b7SVivek Goyal Block layer bio throttling support. It can be used to limit 97e43473b7SVivek Goyal the IO rate to a device. IO rate policies are per cgroup and 98e43473b7SVivek Goyal one needs to mount and use blkio cgroup controller for creating 99e43473b7SVivek Goyal cgroups and specifying per device IO rate policies. 100e43473b7SVivek Goyal 101e43473b7SVivek Goyal See Documentation/cgroups/blkio-controller.txt for more information. 102e43473b7SVivek Goyal 103080506adSPaul Gortmakerconfig BLK_CMDLINE_PARSER 104bab55417SCai Zhiyong bool "Block device command line partition parser" 105bab55417SCai Zhiyong default n 106bab55417SCai Zhiyong ---help--- 107080506adSPaul Gortmaker Enabling this option allows you to specify the partition layout from 108080506adSPaul Gortmaker the kernel boot args. This is typically of use for embedded devices 109080506adSPaul Gortmaker which don't otherwise have any standardized method for listing the 110080506adSPaul Gortmaker partitions on a block device. 111080506adSPaul Gortmaker 112080506adSPaul Gortmaker See Documentation/block/cmdline-partition.txt for more information. 113bab55417SCai Zhiyong 1149be96f3fSAl Viromenu "Partition Types" 1159be96f3fSAl Viro 1169be96f3fSAl Virosource "block/partitions/Kconfig" 1179be96f3fSAl Viro 1189be96f3fSAl Viroendmenu 1199be96f3fSAl Viro 1202b9e0aaeSLinus Torvaldsendif # BLOCK 1212b9e0aaeSLinus Torvalds 12299874d50SJens Axboeconfig BLOCK_COMPAT 12399874d50SJens Axboe bool 1242b9e0aaeSLinus Torvalds depends on BLOCK && COMPAT 12599874d50SJens Axboe default y 12699874d50SJens Axboe 1273a65dfe8SJens Axboesource block/Kconfig.iosched 128