block/Kconfig

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