mirror of
https://github.com/torvalds/linux.git
synced 2024-11-07 04:32:03 +00:00
db29a6b496
Enable by default support for large devices and files (CONFIG_LBD): - With 1TB disks being a commodity hardware it is quite easy to hit 2TB limitation while building RAIDs etc. and many distros have been using CONFIG_LBD=y by default already (at least Fedora 10 and openSUSE 11.1). - This should also prevent a subtle ext4 filesystem compatibility issue: mke2fs.ext4 defaults to creating filesystems with huge_files feature enabled and such filesystems cannot be later mounted read-write on machines with CONFIG_LBD=n (it should be quite easy to hit this issue when trying to use filesystem created using distro kernel on system running the self-build kernel, think about USB disk enclosures & co.). While at it: - Clarify config option help text w.r.t. mounting ext4 filesystems (they can be mounted with CONFIG_LBD=n but in the read-only mode). Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
85 lines
2.5 KiB
Plaintext
85 lines
2.5 KiB
Plaintext
#
|
|
# Block layer core configuration
|
|
#
|
|
menuconfig BLOCK
|
|
bool "Enable the block layer" if EMBEDDED
|
|
default y
|
|
help
|
|
Provide block layer support for the kernel.
|
|
|
|
Disable this option to remove the block layer support from the
|
|
kernel. This may be useful for embedded devices.
|
|
|
|
If this option is disabled:
|
|
|
|
- block device files will become unusable
|
|
- some filesystems (such as ext3) will become unavailable.
|
|
|
|
Also, SCSI character devices and USB storage will be disabled since
|
|
they make use of various block layer definitions and facilities.
|
|
|
|
Say Y here unless you know you really don't want to mount disks and
|
|
suchlike.
|
|
|
|
if BLOCK
|
|
|
|
config LBD
|
|
bool "Support for large block devices and files"
|
|
depends on !64BIT
|
|
default y
|
|
help
|
|
Enable block devices or files of size 2TB and larger.
|
|
|
|
This option is required to support the full capacity of large
|
|
(2TB+) block devices, including RAID, disk, Network Block Device,
|
|
Logical Volume Manager (LVM) and loopback.
|
|
|
|
This option also enables support for single files larger than
|
|
2TB.
|
|
|
|
The ext4 filesystem requires that this feature be enabled in
|
|
order to support filesystems that have the huge_file feature
|
|
enabled. Otherwise, it will refuse to mount in the read-write
|
|
mode any filesystems that use the huge_file feature, which is
|
|
enabled by default by mke2fs.ext4.
|
|
|
|
The GFS2 filesystem also requires this feature.
|
|
|
|
If unsure, say Y.
|
|
|
|
config BLK_DEV_BSG
|
|
bool "Block layer SG support v4 (EXPERIMENTAL)"
|
|
depends on EXPERIMENTAL
|
|
---help---
|
|
Saying Y here will enable generic SG (SCSI generic) v4 support
|
|
for any block device.
|
|
|
|
Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4
|
|
can handle complicated SCSI commands: tagged variable length cdbs
|
|
with bidirectional data transfers and generic request/response
|
|
protocols (e.g. Task Management Functions and SMP in Serial
|
|
Attached SCSI).
|
|
|
|
If unsure, say N.
|
|
|
|
config BLK_DEV_INTEGRITY
|
|
bool "Block layer data integrity support"
|
|
---help---
|
|
Some storage devices allow extra information to be
|
|
stored/retrieved to help protect the data. The block layer
|
|
data integrity option provides hooks which can be used by
|
|
filesystems to ensure better data integrity.
|
|
|
|
Say yes here if you have a storage device that provides the
|
|
T10/SCSI Data Integrity Field or the T13/ATA External Path
|
|
Protection. If in doubt, say N.
|
|
|
|
endif # BLOCK
|
|
|
|
config BLOCK_COMPAT
|
|
bool
|
|
depends on BLOCK && COMPAT
|
|
default y
|
|
|
|
source block/Kconfig.iosched
|