1# 2# Block layer core configuration 3# 4menuconfig BLOCK 5 bool "Enable the block layer" if EMBEDDED 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_INTEGRITY 69 bool "Block layer data integrity support" 70 ---help--- 71 Some storage devices allow extra information to be 72 stored/retrieved to help protect the data. The block layer 73 data integrity option provides hooks which can be used by 74 filesystems to ensure better data integrity. 75 76 Say yes here if you have a storage device that provides the 77 T10/SCSI Data Integrity Field or the T13/ATA External Path 78 Protection. If in doubt, say N. 79 80config BLK_CGROUP 81 bool 82 depends on CGROUPS 83 default n 84 ---help--- 85 Generic block IO controller cgroup interface. This is the common 86 cgroup interface which should be used by various IO controlling 87 policies. 88 89 Currently, CFQ IO scheduler uses it to recognize task groups and 90 control disk bandwidth allocation (proportional time slice allocation) 91 to such task groups. 92 93config DEBUG_BLK_CGROUP 94 bool 95 depends on BLK_CGROUP 96 default n 97 ---help--- 98 Enable some debugging help. Currently it stores the cgroup path 99 in the blk group which can be used by cfq for tracing various 100 group related activity. 101 102endif # BLOCK 103 104config BLOCK_COMPAT 105 bool 106 depends on BLOCK && COMPAT 107 default y 108 109source block/Kconfig.iosched 110