2005-11-04 00:43:35 -07:00
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#
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# Block layer core configuration
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#
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2007-07-10 03:24:11 -07:00
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menuconfig BLOCK
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2011-01-20 15:44:16 -07:00
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bool "Enable the block layer" if EXPERT
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[PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer. Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.
This patch does the following:
(*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
support.
(*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
an item that uses the block layer. This includes:
(*) Block I/O tracing.
(*) Disk partition code.
(*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.
(*) The SCSI layer. As far as I can tell, even SCSI chardevs use the
block layer to do scheduling. Some drivers that use SCSI facilities -
such as USB storage - end up disabled indirectly from this.
(*) Various block-based device drivers, such as IDE and the old CDROM
drivers.
(*) MTD blockdev handling and FTL.
(*) JFFS - which uses set_bdev_super(), something it could avoid doing by
taking a leaf out of JFFS2's book.
(*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
linux/elevator.h contingent on CONFIG_BLOCK being set. sector_div() is,
however, still used in places, and so is still available.
(*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
parts of linux/fs.h.
(*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.
(*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.
(*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
is not enabled.
(*) fs/no-block.c is created to hold out-of-line stubs and things that are
required when CONFIG_BLOCK is not set:
(*) Default blockdev file operations (to give error ENODEV on opening).
(*) Makes some /proc changes:
(*) /proc/devices does not list any blockdevs.
(*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.
(*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.
(*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
given command other than Q_SYNC or if a special device is specified.
(*) In init/do_mounts.c, no reference is made to the blockdev routines if
CONFIG_BLOCK is not defined. This does not prohibit NFS roots or JFFS2.
(*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
error ENOSYS by way of cond_syscall if so).
(*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
CONFIG_BLOCK is not set, since they can't then happen.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 11:45:40 -07:00
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default y
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help
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2008-04-21 00:51:04 -07:00
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Provide block layer support for the kernel.
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[PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer. Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.
This patch does the following:
(*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
support.
(*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
an item that uses the block layer. This includes:
(*) Block I/O tracing.
(*) Disk partition code.
(*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.
(*) The SCSI layer. As far as I can tell, even SCSI chardevs use the
block layer to do scheduling. Some drivers that use SCSI facilities -
such as USB storage - end up disabled indirectly from this.
(*) Various block-based device drivers, such as IDE and the old CDROM
drivers.
(*) MTD blockdev handling and FTL.
(*) JFFS - which uses set_bdev_super(), something it could avoid doing by
taking a leaf out of JFFS2's book.
(*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
linux/elevator.h contingent on CONFIG_BLOCK being set. sector_div() is,
however, still used in places, and so is still available.
(*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
parts of linux/fs.h.
(*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.
(*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.
(*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
is not enabled.
(*) fs/no-block.c is created to hold out-of-line stubs and things that are
required when CONFIG_BLOCK is not set:
(*) Default blockdev file operations (to give error ENODEV on opening).
(*) Makes some /proc changes:
(*) /proc/devices does not list any blockdevs.
(*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.
(*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.
(*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
given command other than Q_SYNC or if a special device is specified.
(*) In init/do_mounts.c, no reference is made to the blockdev routines if
CONFIG_BLOCK is not defined. This does not prohibit NFS roots or JFFS2.
(*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
error ENOSYS by way of cond_syscall if so).
(*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
CONFIG_BLOCK is not set, since they can't then happen.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 11:45:40 -07:00
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2008-04-21 00:51:04 -07:00
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Disable this option to remove the block layer support from the
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kernel. This may be useful for embedded devices.
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If this option is disabled:
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- block device files will become unusable
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- some filesystems (such as ext3) will become unavailable.
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Also, SCSI character devices and USB storage will be disabled since
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they make use of various block layer definitions and facilities.
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[PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer. Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.
This patch does the following:
(*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
support.
(*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
an item that uses the block layer. This includes:
(*) Block I/O tracing.
(*) Disk partition code.
(*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.
(*) The SCSI layer. As far as I can tell, even SCSI chardevs use the
block layer to do scheduling. Some drivers that use SCSI facilities -
such as USB storage - end up disabled indirectly from this.
(*) Various block-based device drivers, such as IDE and the old CDROM
drivers.
(*) MTD blockdev handling and FTL.
(*) JFFS - which uses set_bdev_super(), something it could avoid doing by
taking a leaf out of JFFS2's book.
(*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
linux/elevator.h contingent on CONFIG_BLOCK being set. sector_div() is,
however, still used in places, and so is still available.
(*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
parts of linux/fs.h.
(*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.
(*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.
(*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
is not enabled.
(*) fs/no-block.c is created to hold out-of-line stubs and things that are
required when CONFIG_BLOCK is not set:
(*) Default blockdev file operations (to give error ENODEV on opening).
(*) Makes some /proc changes:
(*) /proc/devices does not list any blockdevs.
(*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.
(*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.
(*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
given command other than Q_SYNC or if a special device is specified.
(*) In init/do_mounts.c, no reference is made to the blockdev routines if
CONFIG_BLOCK is not defined. This does not prohibit NFS roots or JFFS2.
(*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
error ENOSYS by way of cond_syscall if so).
(*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
CONFIG_BLOCK is not set, since they can't then happen.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 11:45:40 -07:00
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Say Y here unless you know you really don't want to mount disks and
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suchlike.
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if BLOCK
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2009-06-18 23:08:50 -07:00
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config LBDAF
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bool "Support for large (2TB+) block devices and files"
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2006-12-04 03:38:31 -07:00
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depends on !64BIT
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2009-04-21 00:27:03 -07:00
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default y
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2005-11-04 00:43:35 -07:00
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help
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2008-12-12 01:51:16 -07:00
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Enable block devices or files of size 2TB and larger.
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2008-04-21 00:51:04 -07:00
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This option is required to support the full capacity of large
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(2TB+) block devices, including RAID, disk, Network Block Device,
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Logical Volume Manager (LVM) and loopback.
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2008-12-12 01:51:16 -07:00
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This option also enables support for single files larger than
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2TB.
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2008-04-21 00:51:04 -07:00
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2009-01-06 13:16:33 -07:00
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The ext4 filesystem requires that this feature be enabled in
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order to support filesystems that have the huge_file feature
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2009-04-21 00:27:03 -07:00
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enabled. Otherwise, it will refuse to mount in the read-write
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mode any filesystems that use the huge_file feature, which is
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enabled by default by mke2fs.ext4.
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2009-01-06 13:16:33 -07:00
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2009-04-21 00:27:03 -07:00
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The GFS2 filesystem also requires this feature.
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If unsure, say Y.
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2005-11-04 00:43:35 -07:00
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2007-07-09 03:38:05 -07:00
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config BLK_DEV_BSG
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2009-08-04 13:10:17 -07:00
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bool "Block layer SG support v4"
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default y
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help
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2008-04-21 00:51:04 -07:00
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Saying Y here will enable generic SG (SCSI generic) v4 support
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for any block device.
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Unlike SG v3 (aka block/scsi_ioctl.c drivers/scsi/sg.c), SG v4
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can handle complicated SCSI commands: tagged variable length cdbs
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with bidirectional data transfers and generic request/response
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protocols (e.g. Task Management Functions and SMP in Serial
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Attached SCSI).
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2009-08-04 13:10:17 -07:00
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This option is required by recent UDEV versions to properly
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access device serial numbers, etc.
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If unsure, say Y.
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2007-07-09 03:38:05 -07:00
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2008-06-30 11:04:41 -07:00
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config BLK_DEV_INTEGRITY
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bool "Block layer data integrity support"
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---help---
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Some storage devices allow extra information to be
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stored/retrieved to help protect the data. The block layer
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data integrity option provides hooks which can be used by
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filesystems to ensure better data integrity.
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Say yes here if you have a storage device that provides the
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T10/SCSI Data Integrity Field or the T13/ATA External Path
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Protection. If in doubt, say N.
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2010-09-15 14:06:35 -07:00
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config BLK_DEV_THROTTLING
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bool "Block layer bio throttling support"
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depends on BLK_CGROUP=y && EXPERIMENTAL
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default n
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---help---
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Block layer bio throttling support. It can be used to limit
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the IO rate to a device. IO rate policies are per cgroup and
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one needs to mount and use blkio cgroup controller for creating
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cgroups and specifying per device IO rate policies.
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See Documentation/cgroups/blkio-controller.txt for more information.
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2007-10-12 17:58:36 -07:00
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endif # BLOCK
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2007-10-12 03:50:41 -07:00
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config BLOCK_COMPAT
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bool
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2007-10-12 17:58:36 -07:00
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depends on BLOCK && COMPAT
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2007-10-12 03:50:41 -07:00
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default y
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2005-11-04 00:43:35 -07:00
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source block/Kconfig.iosched
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