1# 2# Block layer core configuration 3# 4menuconfig BLOCK 5 bool "Enable the block layer" if EXPERT 6 default y 7 help 8 Provide block layer support for the kernel. 9 10 Disable this option to remove the block layer support from the 11 kernel. This may be useful for embedded devices. 12 13 If this option is disabled: 14 15 - block device files will become unusable 16 - some filesystems (such as ext3) will become unavailable. 17 18 Also, SCSI character devices and USB storage will be disabled since 19 they make use of various block layer definitions and facilities. 20 21 Say Y here unless you know you really don't want to mount disks and 22 suchlike. 23 24if BLOCK 25 26config LBDAF 27 bool "Support for large (2TB+) block devices and files" 28 depends on !64BIT 29 default y 30 help 31 Enable block devices or files of size 2TB and larger. 32 33 This option is required to support the full capacity of large 34 (2TB+) block devices, including RAID, disk, Network Block Device, 35 Logical Volume Manager (LVM) and loopback. 36 37 This option also enables support for single files larger than 38 2TB. 39 40 The ext4 filesystem requires that this feature be enabled in 41 order to support filesystems that have the huge_file feature 42 enabled. Otherwise, it will refuse to mount in the read-write 43 mode any filesystems that use the huge_file feature, which is 44 enabled by default by mke2fs.ext4. 45 46 The GFS2 filesystem also requires this feature. 47 48 If unsure, say Y. 49 50config BLK_DEV_BSG 51 bool "Block layer SG support v4" 52 default y 53 help 54 Saying Y here will enable generic SG (SCSI generic) v4 support 55 for any block device. 56 57 Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4 58 can handle complicated SCSI commands: tagged variable length cdbs 59 with bidirectional data transfers and generic request/response 60 protocols (e.g. Task Management Functions and SMP in Serial 61 Attached SCSI). 62 63 This option is required by recent UDEV versions to properly 64 access device serial numbers, etc. 65 66 If unsure, say Y. 67 68config BLK_DEV_BSGLIB 69 bool "Block layer SG support v4 helper lib" 70 default n 71 select BLK_DEV_BSG 72 help 73 Subsystems will normally enable this if needed. Users will not 74 normally need to manually enable this. 75 76 If unsure, say N. 77 78config BLK_DEV_INTEGRITY 79 bool "Block layer data integrity support" 80 ---help--- 81 Some storage devices allow extra information to be 82 stored/retrieved to help protect the data. The block layer 83 data integrity option provides hooks which can be used by 84 filesystems to ensure better data integrity. 85 86 Say yes here if you have a storage device that provides the 87 T10/SCSI Data Integrity Field or the T13/ATA External Path 88 Protection. If in doubt, say N. 89 90config BLK_DEV_THROTTLING 91 bool "Block layer bio throttling support" 92 depends on BLK_CGROUP=y 93 default n 94 ---help--- 95 Block layer bio throttling support. It can be used to limit 96 the IO rate to a device. IO rate policies are per cgroup and 97 one needs to mount and use blkio cgroup controller for creating 98 cgroups and specifying per device IO rate policies. 99 100 See Documentation/cgroups/blkio-controller.txt for more information. 101 102config BLK_CMDLINE_PARSER 103 bool "Block device command line partition parser" 104 default n 105 ---help--- 106 Enabling this option allows you to specify the partition layout from 107 the kernel boot args. This is typically of use for embedded devices 108 which don't otherwise have any standardized method for listing the 109 partitions on a block device. 110 111 See Documentation/block/cmdline-partition.txt for more information. 112 113menu "Partition Types" 114 115source "block/partitions/Kconfig" 116 117endmenu 118 119endif # BLOCK 120 121config BLOCK_COMPAT 122 bool 123 depends on BLOCK && COMPAT 124 default y 125 126source block/Kconfig.iosched 127