2005-04-16 22:20:36 +00:00
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#
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# Block device driver configuration
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#
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2007-07-10 10:26:06 +00:00
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menuconfig BLK_DEV
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bool "Block devices"
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depends on BLOCK
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default y
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2007-08-18 10:56:21 +00:00
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---help---
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Say Y here to get to see options for various different block device
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drivers. This option alone does not add any kernel code.
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If you say N, all options in this submenu will be skipped and disabled;
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only do this if you know what you are doing.
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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 18:45:40 +00:00
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2007-07-10 10:26:06 +00:00
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if BLK_DEV
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2005-04-16 22:20:36 +00:00
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2013-10-25 10:52:25 +00:00
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config BLK_DEV_NULL_BLK
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tristate "Null test block driver"
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2005-04-16 22:20:36 +00:00
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config BLK_DEV_FD
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tristate "Normal floppy disk support"
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2005-09-06 00:48:42 +00:00
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depends on ARCH_MAY_HAVE_PC_FDC
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2005-04-16 22:20:36 +00:00
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---help---
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If you want to use the floppy disk drive(s) of your PC under Linux,
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say Y. Information about this driver, especially important for IBM
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2008-11-13 21:33:24 +00:00
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Thinkpad users, is contained in
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<file:Documentation/blockdev/floppy.txt>.
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2005-04-16 22:20:36 +00:00
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That file also contains the location of the Floppy driver FAQ as
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well as location of the fdutils package used to configure additional
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parameters of the driver at run time.
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To compile this driver as a module, choose M here: the
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module will be called floppy.
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config AMIGA_FLOPPY
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tristate "Amiga floppy support"
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depends on AMIGA
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config ATARI_FLOPPY
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tristate "Atari floppy support"
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depends on ATARI
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config MAC_FLOPPY
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tristate "Support for PowerMac floppy"
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depends on PPC_PMAC && !PPC_PMAC64
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help
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If you have a SWIM-3 (Super Woz Integrated Machine 3; from Apple)
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floppy controller, say Y here. Most commonly found in PowerMacs.
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2008-11-15 15:10:10 +00:00
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config BLK_DEV_SWIM
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tristate "Support for SWIM Macintosh floppy"
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depends on M68K && MAC
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help
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You should select this option if you want floppy support
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and you don't have a II, IIfx, Q900, Q950 or AV series.
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2005-04-16 22:20:36 +00:00
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config AMIGA_Z2RAM
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tristate "Amiga Zorro II ramdisk support"
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depends on ZORRO
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help
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This enables support for using Chip RAM and Zorro II RAM as a
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ramdisk or as a swap partition. Say Y if you want to include this
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driver in the kernel.
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To compile this driver as a module, choose M here: the
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module will be called z2ram.
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2010-05-11 07:02:55 +00:00
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config GDROM
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tristate "SEGA Dreamcast GD-ROM drive"
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depends on SH_DREAMCAST
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2017-01-28 08:32:51 +00:00
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select BLK_SCSI_REQUEST # only for the generic cdrom code
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2010-05-11 07:02:55 +00:00
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help
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A standard SEGA Dreamcast comes with a modified CD ROM drive called a
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"GD-ROM" by SEGA to signify it is capable of reading special disks
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with up to 1 GB of data. This drive will also read standard CD ROM
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disks. Select this option to access any disks in your GD ROM drive.
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Most users will want to say "Y" here.
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You can also build this as a module which will be called gdrom.
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2005-04-16 22:20:36 +00:00
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config PARIDE
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tristate "Parallel port IDE device support"
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2006-01-06 08:19:49 +00:00
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depends on PARPORT_PC
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2005-04-16 22:20:36 +00:00
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---help---
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There are many external CD-ROM and disk devices that connect through
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your computer's parallel port. Most of them are actually IDE devices
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using a parallel port IDE adapter. This option enables the PARIDE
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subsystem which contains drivers for many of these external drives.
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2008-11-13 21:33:24 +00:00
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Read <file:Documentation/blockdev/paride.txt> for more information.
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2005-04-16 22:20:36 +00:00
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If you have said Y to the "Parallel-port support" configuration
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option, you may share a single port between your printer and other
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parallel port devices. Answer Y to build PARIDE support into your
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kernel, or M if you would like to build it as a loadable module. If
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your parallel port support is in a loadable module, you must build
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PARIDE as a module. If you built PARIDE support into your kernel,
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you may still build the individual protocol modules and high-level
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drivers as loadable modules. If you build this support as a module,
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it will be called paride.
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To use the PARIDE support, you must say Y or M here and also to at
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least one high-level driver (e.g. "Parallel port IDE disks",
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"Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
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to at least one protocol driver (e.g. "ATEN EH-100 protocol",
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"MicroSolutions backpack protocol", "DataStor Commuter protocol"
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etc.).
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source "drivers/block/paride/Kconfig"
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2011-08-30 14:34:26 +00:00
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source "drivers/block/mtip32xx/Kconfig"
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zram: promote zram from staging
Zram has lived in staging for a LONG LONG time and have been
fixed/improved by many contributors so code is clean and stable now. Of
course, there are lots of product using zram in real practice.
The major TV companys have used zram as swap since two years ago and
recently our production team released android smart phone with zram
which is used as swap, too and recently Android Kitkat start to use zram
for small memory smart phone. And there was a report Google released
their ChromeOS with zram, too and cyanogenmod have been used zram long
time ago. And I heard some disto have used zram block device for tmpfs.
In addition, I saw many report from many other peoples. For example,
Lubuntu start to use it.
The benefit of zram is very clear. With my experience, one of the
benefit was to remove jitter of video application with backgroud memory
pressure. It would be effect of efficient memory usage by compression
but more issue is whether swap is there or not in the system. Recent
mobile platforms have used JAVA so there are many anonymous pages. But
embedded system normally are reluctant to use eMMC or SDCard as swap
because there is wear-leveling and latency issues so if we do not use
swap, it means we can't reclaim anoymous pages and at last, we could
encounter OOM kill. :(
Although we have real storage as swap, it was a problem, too. Because
it sometime ends up making system very unresponsible caused by slow swap
storage performance.
Quote from Luigi on Google
"Since Chrome OS was mentioned: the main reason why we don't use swap
to a disk (rotating or SSD) is because it doesn't degrade gracefully
and leads to a bad interactive experience. Generally we prefer to
manage RAM at a higher level, by transparently killing and restarting
processes. But we noticed that zram is fast enough to be competitive
with the latter, and it lets us make more efficient use of the
available RAM. " and he announced.
http://www.spinics.net/lists/linux-mm/msg57717.html
Other uses case is to use zram for block device. Zram is block device
so anyone can format the block device and mount on it so some guys on
the internet start zram as /var/tmp.
http://forums.gentoo.org/viewtopic-t-838198-start-0.html
Let's promote zram and enhance/maintain it instead of removing.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Nitin Gupta <ngupta@vflare.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Luigi Semenzato <semenzato@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-30 23:45:52 +00:00
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source "drivers/block/zram/Kconfig"
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2005-04-16 22:20:36 +00:00
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config BLK_CPQ_CISS_DA
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tristate "Compaq Smart Array 5xxx support"
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depends on PCI
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2012-09-09 10:47:47 +00:00
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select CHECK_SIGNATURE
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2017-01-28 08:32:51 +00:00
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select BLK_SCSI_REQUEST
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2005-04-16 22:20:36 +00:00
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help
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This is the driver for Compaq Smart Array 5xxx controllers.
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Everyone using these boards should say Y here.
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2008-11-13 21:33:24 +00:00
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See <file:Documentation/blockdev/cciss.txt> for the current list of
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2005-04-16 22:20:36 +00:00
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boards supported by this driver, and for further information
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on the use of this driver.
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config CISS_SCSI_TAPE
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bool "SCSI tape drive support for Smart Array 5xxx"
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2006-12-07 04:38:40 +00:00
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depends on BLK_CPQ_CISS_DA && PROC_FS
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depends on SCSI=y || SCSI=BLK_CPQ_CISS_DA
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2005-04-16 22:20:36 +00:00
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help
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When enabled (Y), this option allows SCSI tape drives and SCSI medium
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changers (tape robots) to be accessed via a Compaq 5xxx array
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2008-11-13 21:33:24 +00:00
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controller. (See <file:Documentation/blockdev/cciss.txt> for more details.)
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2005-04-16 22:20:36 +00:00
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"SCSI support" and "SCSI tape support" must also be enabled for this
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option to work.
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When this option is disabled (N), the SCSI portion of the driver
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is not compiled.
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config BLK_DEV_DAC960
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tristate "Mylex DAC960/DAC1100 PCI RAID Controller support"
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depends on PCI
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help
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This driver adds support for the Mylex DAC960, AcceleRAID, and
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eXtremeRAID PCI RAID controllers. See the file
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2008-11-13 21:33:24 +00:00
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<file:Documentation/blockdev/README.DAC960> for further information
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about this driver.
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2005-04-16 22:20:36 +00:00
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To compile this driver as a module, choose M here: the
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module will be called DAC960.
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config BLK_DEV_UMEM
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2012-10-23 20:01:51 +00:00
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tristate "Micro Memory MM5415 Battery Backed RAM support"
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depends on PCI
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2005-04-16 22:20:36 +00:00
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---help---
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Saying Y here will include support for the MM5415 family of
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battery backed (Non-volatile) RAM cards.
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<http://www.umem.com/>
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The cards appear as block devices that can be partitioned into
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as many as 15 partitions.
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To compile this driver as a module, choose M here: the
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module will be called umem.
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The umem driver has not yet been allocated a MAJOR number, so
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2006-10-03 20:17:48 +00:00
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one is chosen dynamically.
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2005-04-16 22:20:36 +00:00
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config BLK_DEV_UBD
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bool "Virtual block device"
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depends on UML
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---help---
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The User-Mode Linux port includes a driver called UBD which will let
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you access arbitrary files on the host computer as block devices.
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Unless you know that you do not need such virtual block devices say
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Y here.
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config BLK_DEV_UBD_SYNC
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bool "Always do synchronous disk IO for UBD"
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depends on BLK_DEV_UBD
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---help---
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Writes to the virtual block device are not immediately written to the
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host's disk; this may cause problems if, for example, the User-Mode
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Linux 'Virtual Machine' uses a journalling filesystem and the host
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computer crashes.
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Synchronous operation (i.e. always writing data to the host's disk
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immediately) is configurable on a per-UBD basis by using a special
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kernel command line option. Alternatively, you can say Y here to
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turn on synchronous operation by default for all block devices.
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If you're running a journalling file system (like reiserfs, for
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example) in your virtual machine, you will want to say Y here. If
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you care for the safety of the data in your virtual machine, Y is a
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wise choice too. In all other cases (for example, if you're just
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playing around with User-Mode Linux) you can choose N.
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config BLK_DEV_COW_COMMON
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bool
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default BLK_DEV_UBD
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config BLK_DEV_LOOP
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tristate "Loopback device support"
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---help---
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Saying Y here will allow you to use a regular file as a block
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device; you can then create a file system on that block device and
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mount it just as you would mount other block devices such as hard
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drive partitions, CD-ROM drives or floppy drives. The loop devices
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are block special device files with major number 7 and typically
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called /dev/loop0, /dev/loop1 etc.
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This is useful if you want to check an ISO 9660 file system before
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burning the CD, or if you want to use floppy images without first
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writing them to floppy. Furthermore, some Linux distributions avoid
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the need for a dedicated Linux partition by keeping their complete
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root file system inside a DOS FAT file using this loop device
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driver.
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To use the loop device, you need the losetup utility, found in the
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util-linux package, see
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2017-03-27 12:44:06 +00:00
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<https://www.kernel.org/pub/linux/utils/util-linux/>.
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2005-04-16 22:20:36 +00:00
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The loop device driver can also be used to "hide" a file system in
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a disk partition, floppy, or regular file, either using encryption
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(scrambling the data) or steganography (hiding the data in the low
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bits of, say, a sound file). This is also safe if the file resides
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on a remote file server.
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There are several ways of encrypting disks. Some of these require
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kernel patches. The vanilla kernel offers the cryptoloop option
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and a Device Mapper target (which is superior, as it supports all
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file systems). If you want to use the cryptoloop, say Y to both
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LOOP and CRYPTOLOOP, and make sure you have a recent (version 2.12
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or later) version of util-linux. Additionally, be aware that
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the cryptoloop is not safe for storing journaled filesystems.
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Note that this loop device has nothing to do with the loopback
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device used for network connections from the machine to itself.
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To compile this driver as a module, choose M here: the
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module will be called loop.
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Most users will answer N here.
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2011-07-31 20:08:04 +00:00
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config BLK_DEV_LOOP_MIN_COUNT
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int "Number of loop devices to pre-create at init time"
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depends on BLK_DEV_LOOP
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default 8
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help
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Static number of loop devices to be unconditionally pre-created
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at init time.
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This default value can be overwritten on the kernel command
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line or with module-parameter loop.max_loop.
|
|
|
|
|
|
|
|
The historic default is 8. If a late 2011 version of losetup(8)
|
|
|
|
is used, it can be set to 0, since needed loop devices can be
|
|
|
|
dynamically allocated with the /dev/loop-control interface.
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
config BLK_DEV_CRYPTOLOOP
|
|
|
|
tristate "Cryptoloop Support"
|
|
|
|
select CRYPTO
|
2006-12-02 03:36:03 +00:00
|
|
|
select CRYPTO_CBC
|
2005-04-16 22:20:36 +00:00
|
|
|
depends on BLK_DEV_LOOP
|
|
|
|
---help---
|
|
|
|
Say Y here if you want to be able to use the ciphers that are
|
|
|
|
provided by the CryptoAPI as loop transformation. This might be
|
|
|
|
used as hard disk encryption.
|
|
|
|
|
|
|
|
WARNING: This device is not safe for journaled file systems like
|
|
|
|
ext3 or Reiserfs. Please use the Device Mapper crypto module
|
|
|
|
instead, which can be configured to be on-disk compatible with the
|
|
|
|
cryptoloop device.
|
|
|
|
|
2009-09-25 23:07:19 +00:00
|
|
|
source "drivers/block/drbd/Kconfig"
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
config BLK_DEV_NBD
|
|
|
|
tristate "Network block device support"
|
|
|
|
depends on NET
|
|
|
|
---help---
|
|
|
|
Saying Y here will allow your computer to be a client for network
|
|
|
|
block devices, i.e. it will be able to use block devices exported by
|
|
|
|
servers (mount file systems on them etc.). Communication between
|
|
|
|
client and server works over TCP/IP networking, but to the client
|
|
|
|
program this is hidden: it looks like a regular local file access to
|
|
|
|
a block device special file such as /dev/nd0.
|
|
|
|
|
|
|
|
Network block devices also allows you to run a block-device in
|
|
|
|
userland (making server and client physically the same computer,
|
|
|
|
communicating using the loopback network device).
|
|
|
|
|
2008-11-13 21:33:24 +00:00
|
|
|
Read <file:Documentation/blockdev/nbd.txt> for more information,
|
|
|
|
especially about where to find the server code, which runs in user
|
|
|
|
space and does not need special kernel support.
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
Note that this has nothing to do with the network file systems NFS
|
|
|
|
or Coda; you can say N here even if you intend to use NFS or Coda.
|
|
|
|
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
|
|
module will be called nbd.
|
|
|
|
|
|
|
|
If unsure, say N.
|
|
|
|
|
2013-10-15 20:19:07 +00:00
|
|
|
config BLK_DEV_SKD
|
|
|
|
tristate "STEC S1120 Block Driver"
|
|
|
|
depends on PCI
|
|
|
|
depends on 64BIT
|
|
|
|
---help---
|
|
|
|
Saying Y or M here will enable support for the
|
|
|
|
STEC, Inc. S1120 PCIe SSD.
|
|
|
|
|
|
|
|
Use device /dev/skd$N amd /dev/skd$Np$M.
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
config BLK_DEV_SX8
|
|
|
|
tristate "Promise SATA SX8 support"
|
|
|
|
depends on PCI
|
|
|
|
---help---
|
|
|
|
Saying Y or M here will enable support for the
|
|
|
|
Promise SATA SX8 controllers.
|
|
|
|
|
|
|
|
Use devices /dev/sx8/$N and /dev/sx8/$Np$M.
|
|
|
|
|
|
|
|
config BLK_DEV_RAM
|
rewrite rd
This is a rewrite of the ramdisk block device driver.
The old one is really difficult because it effectively implements a block
device which serves data out of its own buffer cache. It relies on the dirty
bit being set, to pin its backing store in cache, however there are non
trivial paths which can clear the dirty bit (eg. try_to_free_buffers()),
which had recently lead to data corruption. And in general it is completely
wrong for a block device driver to do this.
The new one is more like a regular block device driver. It has no idea about
vm/vfs stuff. It's backing store is similar to the buffer cache (a simple
radix-tree of pages), but it doesn't know anything about page cache (the pages
in the radix tree are not pagecache pages).
There is one slight downside -- direct block device access and filesystem
metadata access goes through an extra copy and gets stored in RAM twice.
However, this downside is only slight, because the real buffercache of the
device is now reclaimable (because we're not playing crazy games with it), so
under memory intensive situations, footprint should effectively be the same --
maybe even a slight advantage to the new driver because it can also reclaim
buffer heads.
The fact that it now goes through all the regular vm/fs paths makes it
much more useful for testing, too.
text data bss dec hex filename
2837 849 384 4070 fe6 drivers/block/rd.o
3528 371 12 3911 f47 drivers/block/brd.o
Text is larger, but data and bss are smaller, making total size smaller.
A few other nice things about it:
- Similar structure and layout to the new loop device handlinag.
- Dynamic ramdisk creation.
- Runtime flexible buffer head size (because it is no longer part of the
ramdisk code).
- Boot / load time flexible ramdisk size, which could easily be extended
to a per-ramdisk runtime changeable size (eg. with an ioctl).
- Can use highmem for the backing store.
[akpm@linux-foundation.org: fix build]
[byron.bbradley@gmail.com: make rd_size non-static]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Byron Bradley <byron.bbradley@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 12:19:49 +00:00
|
|
|
tristate "RAM block device support"
|
2017-01-26 00:54:45 +00:00
|
|
|
select DAX if BLK_DEV_RAM_DAX
|
2005-04-16 22:20:36 +00:00
|
|
|
---help---
|
|
|
|
Saying Y here will allow you to use a portion of your RAM memory as
|
|
|
|
a block device, so that you can make file systems on it, read and
|
|
|
|
write to it and do all the other things that you can do with normal
|
|
|
|
block devices (such as hard drives). It is usually used to load and
|
|
|
|
store a copy of a minimal root file system off of a floppy into RAM
|
|
|
|
during the initial install of Linux.
|
|
|
|
|
2008-11-13 21:33:24 +00:00
|
|
|
Note that the kernel command line option "ramdisk=XX" is now obsolete.
|
|
|
|
For details, read <file:Documentation/blockdev/ramdisk.txt>.
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
To compile this driver as a module, choose M here: the
|
2014-01-23 23:53:46 +00:00
|
|
|
module will be called brd. An alias "rd" has been defined
|
|
|
|
for historical reasons.
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
Most normal users won't need the RAM disk functionality, and can
|
|
|
|
thus say N here.
|
|
|
|
|
|
|
|
config BLK_DEV_RAM_COUNT
|
2006-03-28 09:56:17 +00:00
|
|
|
int "Default number of RAM disks"
|
2005-04-16 22:20:36 +00:00
|
|
|
default "16"
|
2006-03-28 09:56:17 +00:00
|
|
|
depends on BLK_DEV_RAM
|
2005-04-16 22:20:36 +00:00
|
|
|
help
|
2007-10-19 21:05:02 +00:00
|
|
|
The default value is 16 RAM disks. Change this if you know what you
|
2005-04-16 22:20:36 +00:00
|
|
|
are doing. If you boot from a filesystem that needs to be extracted
|
|
|
|
in memory, you will need at least one RAM disk (e.g. root on cramfs).
|
|
|
|
|
|
|
|
config BLK_DEV_RAM_SIZE
|
|
|
|
int "Default RAM disk size (kbytes)"
|
|
|
|
depends on BLK_DEV_RAM
|
|
|
|
default "4096"
|
|
|
|
help
|
|
|
|
The default value is 4096 kilobytes. Only change this if you know
|
2007-10-19 21:05:02 +00:00
|
|
|
what you are doing.
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2015-02-16 23:59:41 +00:00
|
|
|
config BLK_DEV_RAM_DAX
|
|
|
|
bool "Support Direct Access (DAX) to RAM block devices"
|
|
|
|
depends on BLK_DEV_RAM && FS_DAX
|
2008-02-08 12:19:50 +00:00
|
|
|
default n
|
|
|
|
help
|
2015-02-16 23:59:41 +00:00
|
|
|
Support filesystems using DAX to access RAM block devices. This
|
|
|
|
avoids double-buffering data in the page cache before copying it
|
|
|
|
to the block device. Answering Y will slightly enlarge the kernel,
|
|
|
|
and will prevent RAM block device backing store memory from being
|
2008-02-08 12:19:50 +00:00
|
|
|
allocated from highmem (only a problem for highmem systems).
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
config CDROM_PKTCDVD
|
2016-11-21 16:33:17 +00:00
|
|
|
tristate "Packet writing on CD/DVD media (DEPRECATED)"
|
2005-04-16 22:20:36 +00:00
|
|
|
depends on !UML
|
2017-01-28 08:32:51 +00:00
|
|
|
select BLK_SCSI_REQUEST
|
2005-04-16 22:20:36 +00:00
|
|
|
help
|
2016-11-21 16:33:17 +00:00
|
|
|
Note: This driver is deprecated and will be removed from the
|
|
|
|
kernel in the near future!
|
|
|
|
|
2006-12-08 10:36:10 +00:00
|
|
|
If you have a CDROM/DVD drive that supports packet writing, say
|
|
|
|
Y to include support. It should work with any MMC/Mt Fuji
|
|
|
|
compliant ATAPI or SCSI drive, which is just about any newer
|
|
|
|
DVD/CD writer.
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2006-12-08 10:36:10 +00:00
|
|
|
Currently only writing to CD-RW, DVD-RW, DVD+RW and DVDRAM discs
|
|
|
|
is possible.
|
2005-04-16 22:20:36 +00:00
|
|
|
DVD-RW disks must be in restricted overwrite mode.
|
|
|
|
|
2006-12-08 10:36:10 +00:00
|
|
|
See the file <file:Documentation/cdrom/packet-writing.txt>
|
|
|
|
for further information on the use of this driver.
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
To compile this driver as a module, choose M here: the
|
|
|
|
module will be called pktcdvd.
|
|
|
|
|
|
|
|
config CDROM_PKTCDVD_BUFFERS
|
|
|
|
int "Free buffers for data gathering"
|
|
|
|
depends on CDROM_PKTCDVD
|
|
|
|
default "8"
|
|
|
|
help
|
|
|
|
This controls the maximum number of active concurrent packets. More
|
|
|
|
concurrent packets can increase write performance, but also require
|
|
|
|
more memory. Each concurrent packet will require approximately 64Kb
|
2006-02-05 07:27:47 +00:00
|
|
|
of non-swappable kernel memory, memory which will be allocated when
|
|
|
|
a disc is opened for writing.
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
config CDROM_PKTCDVD_WCACHE
|
2012-10-23 20:01:51 +00:00
|
|
|
bool "Enable write caching"
|
|
|
|
depends on CDROM_PKTCDVD
|
2005-04-16 22:20:36 +00:00
|
|
|
help
|
|
|
|
If enabled, write caching will be set for the CD-R/W device. For now
|
|
|
|
this option is dangerous unless the CD-RW media is known good, as we
|
|
|
|
don't do deferred write error handling yet.
|
|
|
|
|
|
|
|
config ATA_OVER_ETH
|
|
|
|
tristate "ATA over Ethernet support"
|
|
|
|
depends on NET
|
|
|
|
help
|
|
|
|
This driver provides Support for ATA over Ethernet block
|
|
|
|
devices like the Coraid EtherDrive (R) Storage Blade.
|
|
|
|
|
2007-07-16 11:03:56 +00:00
|
|
|
config SUNVDC
|
|
|
|
tristate "Sun Virtual Disk Client support"
|
|
|
|
depends on SUN_LDOMS
|
|
|
|
help
|
|
|
|
Support for virtual disk devices as a client under Sun
|
|
|
|
Logical Domains.
|
|
|
|
|
2007-05-10 13:46:00 +00:00
|
|
|
source "drivers/s390/block/Kconfig"
|
|
|
|
|
2007-07-17 11:03:39 +00:00
|
|
|
config XILINX_SYSACE
|
|
|
|
tristate "Xilinx SystemACE support"
|
2009-05-11 13:49:12 +00:00
|
|
|
depends on 4xx || MICROBLAZE
|
2007-07-17 11:03:39 +00:00
|
|
|
help
|
|
|
|
Include support for the Xilinx SystemACE CompactFlash interface
|
|
|
|
|
2007-07-18 01:37:06 +00:00
|
|
|
config XEN_BLKDEV_FRONTEND
|
|
|
|
tristate "Xen virtual block device support"
|
|
|
|
depends on XEN
|
|
|
|
default y
|
2009-02-09 20:05:51 +00:00
|
|
|
select XEN_XENBUS_FRONTEND
|
2007-07-18 01:37:06 +00:00
|
|
|
help
|
|
|
|
This driver implements the front-end of the Xen virtual
|
|
|
|
block device driver. It communicates with a back-end driver
|
|
|
|
in another domain which drives the actual block device.
|
|
|
|
|
2011-04-18 18:24:23 +00:00
|
|
|
config XEN_BLKDEV_BACKEND
|
2011-08-03 15:12:17 +00:00
|
|
|
tristate "Xen block-device backend driver"
|
2011-04-18 18:24:23 +00:00
|
|
|
depends on XEN_BACKEND
|
|
|
|
help
|
|
|
|
The block-device backend driver allows the kernel to export its
|
|
|
|
block devices to other guests via a high-performance shared-memory
|
|
|
|
interface.
|
|
|
|
|
2011-05-12 20:10:55 +00:00
|
|
|
The corresponding Linux frontend driver is enabled by the
|
|
|
|
CONFIG_XEN_BLKDEV_FRONTEND configuration option.
|
|
|
|
|
|
|
|
The backend driver attaches itself to a any block device specified
|
|
|
|
in the XenBus configuration. There are no limits to what the block
|
|
|
|
device as long as it has a major and minor.
|
|
|
|
|
|
|
|
If you are compiling a kernel to run in a Xen block backend driver
|
|
|
|
domain (often this is domain 0) you should say Y here. To
|
|
|
|
compile this driver as a module, chose M here: the module
|
|
|
|
will be called xen-blkback.
|
|
|
|
|
|
|
|
|
2007-10-22 01:03:38 +00:00
|
|
|
config VIRTIO_BLK
|
2012-10-23 20:01:51 +00:00
|
|
|
tristate "Virtio block driver"
|
|
|
|
depends on VIRTIO
|
2007-10-22 01:03:38 +00:00
|
|
|
---help---
|
2007-11-08 02:46:31 +00:00
|
|
|
This is the virtual block driver for virtio. It can be used with
|
|
|
|
lguest or QEMU based VMMs (like KVM or Xen). Say Y or M.
|
2007-10-22 01:03:38 +00:00
|
|
|
|
2017-01-28 08:32:53 +00:00
|
|
|
config VIRTIO_BLK_SCSI
|
|
|
|
bool "SCSI passthrough request for the Virtio block driver"
|
|
|
|
depends on VIRTIO_BLK
|
|
|
|
select BLK_SCSI_REQUEST
|
|
|
|
---help---
|
|
|
|
Enable support for SCSI passthrough (e.g. the SG_IO ioctl) on
|
|
|
|
virtio-blk devices. This is only supported for the legacy
|
|
|
|
virtio protocol and not enabled by default by any hypervisor.
|
2017-04-25 04:07:10 +00:00
|
|
|
You probably want to use virtio-scsi instead.
|
2017-01-28 08:32:53 +00:00
|
|
|
|
2010-08-12 23:11:25 +00:00
|
|
|
config BLK_DEV_RBD
|
|
|
|
tristate "Rados block device (RBD)"
|
2012-10-23 20:01:51 +00:00
|
|
|
depends on INET && BLOCK
|
2010-08-12 23:11:25 +00:00
|
|
|
select CEPH_LIB
|
|
|
|
select LIBCRC32C
|
|
|
|
select CRYPTO_AES
|
|
|
|
select CRYPTO
|
|
|
|
default n
|
|
|
|
help
|
|
|
|
Say Y here if you want include the Rados block device, which stripes
|
|
|
|
a block device over objects stored in the Ceph distributed object
|
|
|
|
store.
|
|
|
|
|
|
|
|
More information at http://ceph.newdream.net/.
|
|
|
|
|
|
|
|
If unsure, say N.
|
|
|
|
|
2013-02-05 13:15:02 +00:00
|
|
|
config BLK_DEV_RSXX
|
2013-06-18 19:43:58 +00:00
|
|
|
tristate "IBM Flash Adapter 900GB Full Height PCIe Device Driver"
|
2013-02-05 13:15:02 +00:00
|
|
|
depends on PCI
|
|
|
|
help
|
|
|
|
Device driver for IBM's high speed PCIe SSD
|
2013-06-18 19:43:58 +00:00
|
|
|
storage device: Flash Adapter 900GB Full Height.
|
2013-02-05 13:15:02 +00:00
|
|
|
|
|
|
|
To compile this driver as a module, choose M here: the
|
|
|
|
module will be called rsxx.
|
|
|
|
|
2007-07-10 10:26:06 +00:00
|
|
|
endif # BLK_DEV
|