SD/MMC cards tend to support an erase operation. In addition, eMMC v4.4
cards can support secure erase, trim and secure trim operations that are
all variants of the basic erase command.
SD/MMC device attributes "erase_size" and "preferred_erase_size" have been
added.
"erase_size" is the minimum size, in bytes, of an erase operation. For
MMC, "erase_size" is the erase group size reported by the card. Note that
"erase_size" does not apply to trim or secure trim operations where the
minimum size is always one 512 byte sector. For SD, "erase_size" is 512
if the card is block-addressed, 0 otherwise.
SD/MMC cards can erase an arbitrarily large area up to and
including the whole card. When erasing a large area it may
be desirable to do it in smaller chunks for three reasons:
1. A single erase command will make all other I/O on the card
wait. This is not a problem if the whole card is being erased, but
erasing one partition will make I/O for another partition on the
same card wait for the duration of the erase - which could be a
several minutes.
2. To be able to inform the user of erase progress.
3. The erase timeout becomes too large to be very useful.
Because the erase timeout contains a margin which is multiplied by
the size of the erase area, the value can end up being several
minutes for large areas.
"erase_size" is not the most efficient unit to erase (especially for SD
where it is just one sector), hence "preferred_erase_size" provides a good
chunk size for erasing large areas.
For MMC, "preferred_erase_size" is the high-capacity erase size if a card
specifies one, otherwise it is based on the capacity of the card.
For SD, "preferred_erase_size" is the allocation unit size specified by
the card.
"preferred_erase_size" is in bytes.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Madhusudhan Chikkature <madhu.cr@ti.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ben Gardiner <bengardiner@nanometrics.ca>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Having both IO-mapping.txt and io-mapping.txt in Documentation/
was confusing and/or bothersome to some people, so rename
IO-mapping.txt to bus-virt-phys-mapping.txt. Also update
Documentation/00-INDEX for both of these files.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kees Bakker <kees.bakker@xs4all.nl>
Cc: Keith Packard <keithp@keithp.com>
add btmrvl.txt to Documentation/
This patch incorporates a lot of comments given by
Nicolas Pitre <nico@marvell.com>. Many thanks to Nicolas Pitre.
Signed-off-by: Rahul Tank <rahult@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
cgroup documentation was moved to Documentation/cgroups/. There are some
places that still refer to Documentation/controllers/,
Documentation/cgroups.txt and Documentation/cpusets.txt. Fix those.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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>
The Documentation/i386 and Documentation/x86_64 directories and their
contents have been moved into Documentation/x86. Fix references to
those files accordingly.
Signed-off-by: Uwe Hermann <uwe@hermann-uwe.de>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'docs' of git://git.lwn.net/linux-2.6:
Document panic_on_unrecovered_nmi sysctl
Add a reference to paper to SubmittingPatches
Add kerneldoc documentation for new printk format extensions
Remove videobook.tmpl
doc: Test-by?
Add the development process document
Documentation/block/data-integrity.txt: Fix section numbers
This is an extended document intended to help interested developers, their
managers, and their employers work with the kernel development process.
This work was supported by the Linux Foundation.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Move mtrr.txt to the Documentation/x86/ subdirectory.
Add 00-INDEX to the Documentation/x86/ subdirectory.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
As requested by Sam Ravnborg: Remove Documentation/smart-config.txt.
It is outdated and has been (functionally) replaced by
Documentation/kbuild/*.txt.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Create Documentation/PCI/ and move PCI-related files to it.
Fix a few instances of trailing whitespace.
Update references to the new file locations.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We have two directories with timer related information in
Documentation/: hrtimers/ and hrtimer/. timer_stats are not restricted
to hrtimers. Move all those files into Documentation/timers where we
can pile up other timer related docs as well.
Pointed-out-by: Randy Dunlap <randy@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This file is nfs-related. (Maybe Documentation/filesystems/ would
benefit from a separate nfs/ directory at some point.)
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Documentation/ is a little large, and filesystems/ seems an obvious
place for this file.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Adrian Hunter
Huang Shijie
Randy Dunlap
Jonathan Corbet
Bing Zhao
Thadeu Lima de Souza Cascardo
Linus Torvalds
Uwe Hermann
Ingo Molnar
Mark Asselstine
Adrian Bunk
Thomas Gleixner
J. Bruce Fields