summaryrefslogtreecommitdiff
path: root/Documentation/blockdev
AgeCommit message (Collapse)Author
2014-01-30zram: remove old private project commentMinchan Kim
Remove the old private compcache project address so upcoming patches should be sent to LKML because we Linux kernel community will take care. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-30zram: promote zram from stagingMinchan Kim
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>
2014-01-23Documentation/blockdev/ramdisk.txt: updatesFabian Frederick
- ramdisk_blocksize doesn't exist anymore - Module parameters added to documentation Signed-off-by: Fabian Frederick <fabf@skynet.be> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-08floppy: Correct documentation of driver options when used as a module.Ben Harris
The options have to be passed space-separated and prefixed by "floppy=", rather than separately and unprefixed. This fixes <http://bugs.debian.org/726655>. Signed-off-by: Ben Harris <bjh21@cam.ac.uk> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-02-27nbd: update documentation and link to mailinglistWouter Verhelst
Documentation/blockdev/nbd.txt contained some documentation which was horribly outdated and probably still dates from the original patch that added NBD support to the kernel. This patch removes the useless and outdated bits. The tools on nbd.sf.net are fully documented in manpages, which is where documentation for the non-kernel bits should live. Additionally, add a reference to the MAINTAINERS file for the nbd-general mailinglist that is used for discussion of the userland tools and the kernel module already. Signed-off-by: Wouter Verhelst <w@uter.be> Cc: Paul Clements <Paul.Clements@steeleye.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-30Documentation: remove references to /etc/modprobe.confLucas De Marchi
Usage of /etc/modprobe.conf file was deprecated by module-init-tools and is no longer parsed by new kmod tool. References to this file are replaced in Documentation, comments and Kconfig according to the context. There are also some references to the old /etc/modules.conf from 2.4 kernels that are being removed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-16cciss: auto engage SCSI mid layer at driver load timeStephen M. Cameron
A long time ago, probably in 2002, one of the distros, or maybe more than one, loaded block drivers prior to loading the SCSI mid layer. This meant that the cciss driver, being a block driver, could not engage the SCSI mid layer at init time without panicking, and relied on being poked by a userland program after the system was up (and the SCSI mid layer was therefore present) to engage the SCSI mid layer. This is no longer the case, and cciss can safely rely on the SCSI mid layer being present at init time and engage the SCSI mid layer straight away. This means that users will see their tape drives and medium changers at driver load time without need for a script in /etc/rc.d that does this: for x in /proc/driver/cciss/cciss* do echo "engage scsi" > $x done However, if no tape drives or medium changers are detected, the SCSI mid layer will not be engaged. If a tape drive or medium change is later hot-added to the system it will then be necessary to use the above script or similar for the device(s) to be acceesible. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-08-08cciss: Adds simple mode functionalityJoseph Handzik
Signed-off-by: Joseph Handzik <joseph.t.handzik@beardog.cce.hp.com> Acked-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-06-13doc: fix wrong arch/i386 referencesWanlong Gao
Change all "arch/i386" to "arch/x86" in Documentaion/, since the directory has changed. Also update the files which have changed their filename in the meantime accordingly. Signed-off-by: Wanlong Gao <wanlong.gao@gmail.com> [jkosina@suse.cz: reword changelog] Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-05-06cciss: add cciss_tape_cmds module paramterStephen M. Cameron
This is to allow number of commands reserved for use by SCSI tape drives and medium changers to be adjusted at driver load time via the kernel parameter cciss_tape_cmds, with a default value of 6, and a range of 2 - 16 inclusive. Previously, the driver limited the number of commands which could be queued to the SCSI half of the the driver to only 2. This is to fix the problem that if you had more than two tape drives, you couldn't, for example, erase or rewind them all at the same time. Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-04Documentation: update broken web addresses.Justin P. Mattock
Below you will find an updated version from the original series bunching all patches into one big patch updating broken web addresses that are located in Documentation/* Some of the addresses date as far far back as 1995 etc... so searching became a bit difficult, the best way to deal with these is to use web.archive.org to locate these addresses that are outdated. Now there are also some addresses pointing to .spec files some are located, but some(after searching on the companies site)where still no where to be found. In this case I just changed the address to the company site this way the users can contact the company and they can locate them for the users. Signed-off-by: Justin P. Mattock <justinmattock@gmail.com> Signed-off-by: Thomas Weber <weber@corscience.de> Signed-off-by: Mike Frysinger <vapier.adi@gmail.com> Cc: Paulo Marques <pmarques@grupopie.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Michael Neuling <mikey@neuling.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-10-01The DRBD driverPhilipp Reisner
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2009-04-07mflash: initial supportunsik Kim
This driver supports mflash IO mode for linux. Mflash is embedded flash drive and mainly targeted mobile and consumer electronic devices. Internally, mflash has nand flash and other hardware logics and supports 2 different operation (ATA, IO) modes. ATA mode doesn't need any new driver and currently works well under standard IDE subsystem. Actually it's one chip SSD. IO mode is ATA-like custom mode for the host that doesn't have IDE interface. Followings are brief descriptions about IO mode. A. IO mode based on ATA protocol and uses some custom command. (read confirm, write confirm) B. IO mode uses SRAM bus interface. C. IO mode supports 4kB boot area, so host can boot from mflash. This driver is quitely similar to a standard ATA driver, but because of following reasons it is currently seperated with ATA layer. 1. ATA layer deals standard ATA protocol. ATA layer have many low- level device specific interface, but data transfer keeps ATA rule. But, mflash IO mode doesn't. 2. Even though currently not used in mflash driver code, mflash has some custom command and modes. (nand fusing, firmware patch, etc) If this feature supported in linux kernel, ATA layer more altered. 3. Currently PATA platform device driver doesn't support interrupt. (I'm not sure) But, mflash uses interrupt (polling mode is just for debug). 4. mflash is somewhat under-develop product. Even though some company already using mflash their own product, I think more time is needed for standardization of custom command and mode. That time (maybe October) I will talk to with ATA people. If they accept integration, I will integrate. Signed-off-by: unsik Kim <donari75@gmail.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-11-14Create/use more directory structure in the Documentation/ tree.Randy Dunlap
Create Documentation/blockdev/ sub-directory and populate it. Populate the Documentation/serial/ sub-directory. Move MSI-HOWTO.txt to Documentation/PCI/. Move ioctl-number.txt to Documentation/ioctl/. Update all relevant 00-INDEX files. Update all relevant Kconfig files and source files. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>