xref: /linux/block/Kconfig (revision 6a108a14fa356ef607be308b68337939e56ea94e)
13a65dfe8SJens Axboe#
23a65dfe8SJens Axboe# Block layer core configuration
33a65dfe8SJens Axboe#
416ed002fSJan Engelhardtmenuconfig BLOCK
5*6a108a14SDavid 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
687ba1ba12SMartin K. Petersenconfig BLK_DEV_INTEGRITY
697ba1ba12SMartin K. Petersen	bool "Block layer data integrity support"
707ba1ba12SMartin K. Petersen	---help---
717ba1ba12SMartin K. Petersen	Some storage devices allow extra information to be
727ba1ba12SMartin K. Petersen	stored/retrieved to help protect the data.  The block layer
737ba1ba12SMartin K. Petersen	data integrity option provides hooks which can be used by
747ba1ba12SMartin K. Petersen	filesystems to ensure better data integrity.
757ba1ba12SMartin K. Petersen
767ba1ba12SMartin K. Petersen	Say yes here if you have a storage device that provides the
777ba1ba12SMartin K. Petersen	T10/SCSI Data Integrity Field or the T13/ATA External Path
787ba1ba12SMartin K. Petersen	Protection.  If in doubt, say N.
797ba1ba12SMartin K. Petersen
80e43473b7SVivek Goyalconfig BLK_DEV_THROTTLING
81e43473b7SVivek Goyal	bool "Block layer bio throttling support"
82e43473b7SVivek Goyal	depends on BLK_CGROUP=y && EXPERIMENTAL
83e43473b7SVivek Goyal	default n
84e43473b7SVivek Goyal	---help---
85e43473b7SVivek Goyal	Block layer bio throttling support. It can be used to limit
86e43473b7SVivek Goyal	the IO rate to a device. IO rate policies are per cgroup and
87e43473b7SVivek Goyal	one needs to mount and use blkio cgroup controller for creating
88e43473b7SVivek Goyal	cgroups and specifying per device IO rate policies.
89e43473b7SVivek Goyal
90e43473b7SVivek Goyal	See Documentation/cgroups/blkio-controller.txt for more information.
91e43473b7SVivek Goyal
922b9e0aaeSLinus Torvaldsendif # BLOCK
932b9e0aaeSLinus Torvalds
9499874d50SJens Axboeconfig BLOCK_COMPAT
9599874d50SJens Axboe	bool
962b9e0aaeSLinus Torvalds	depends on BLOCK && COMPAT
9799874d50SJens Axboe	default y
9899874d50SJens Axboe
993a65dfe8SJens Axboesource block/Kconfig.iosched
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