Commit Graph

20 Commits

Author SHA1 Message Date
Stefani Seibold
c4e773764c mtd: fix a huge latency problem in the MTD CFI and LPDDR flash drivers.
The use of a memcpy() during a spinlock operation will cause very long
thread context switch delays if the flash chip bandwidth is low and the
data to be copied large, because a spinlock will disable preemption.

For example: A flash with 6,5 MB/s bandwidth will cause under ubifs,
which request sometimes 128 KiB (the flash erase size), a preemption delay of
20 milliseconds. High priority threads will not be served during this
time, regardless whether this threads access the flash or not. This behavior
breaks real time.

The patch changes all the use of spin_lock operations for xxxx->mutex
into mutex operations, which is exact what the name says and means.

I have checked the code of the drivers and there is no use of atomic
pathes like interrupt or timers. The mtdoops facility will also not be used
by this drivers. So it is dave to replace the spin_lock against mutex.

There is no performance regression since the mutex is normally not
acquired.

Changelog:
 06.03.2010 First release
 26.03.2010 Fix mutex[1] issue and tested it for compile failure

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-10 14:22:30 +01:00
Nicolas Pitre
2f82af08fc Nicolas Pitre has a new email address
Due to problems at cam.org, my nico@cam.org email address is no longer
valid.  FRom now on, nico@fluxnic.net should be used instead.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-15 09:37:12 -07:00
Adrian Hunter
69423d99fc [MTD] update internal API to support 64-bit device size
MTD internal API presently uses 32-bit values to represent
device size.  This patch updates them to 64-bits but leaves
the external API unchanged.  Extending the external API
is a separate issue for several reasons.  First, no one
needs it at the moment.  Secondly, whether the implementation
is done with IOCTLs, sysfs or both is still debated.  Thirdly
external API changes require the internal API to be accepted
first.

Note that although the MTD API will be able to support 64-bit
device sizes, existing drivers do not and are not required
to do so, although NAND base has been updated.

In general, changing from 32-bit to 64-bit values cause little
or no changes to the majority of the code with the following
exceptions:
    	- printk message formats
    	- division and modulus of 64-bit values
    	- NAND base support
	- 32-bit local variables used by mtdpart and mtdconcat
	- naughtily assuming one structure maps to another
	in MEMERASE ioctl

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-12-10 13:37:21 +00:00
Adrian Bunk
59018b6d2a MTD/JFFS2: remove CVS keywords
Once upon a time, the MTD repository was using CVS.

This patch therefore removes all usages of the no longer updated CVS
keywords from the MTD code.

This also includes code that printed them to the user.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2008-06-04 17:50:17 +01:00
Adrian Bunk
eb8e31831a [MTD] [NOR] cfi_cmdset_0020.c: make a function static
This patch makes the needlessly global cfi_staa_erase_varsize() static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2008-04-22 15:56:16 +01:00
Harvey Harrison
cb53b3b999 [MTD] replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2008-04-22 12:36:04 +01:00
Dmitry Adamushko
f8e30e447c mtd/chips: add missing set_current_state() to cfi_{amdstd,staa}_sync()
cfi_amdstd_sync() and cfi_staa_sync() call schedule() without changing task's
state appropriately.

In case of e.g.  chip->state == FL_ERASING, cfi_*_sync() will be busy-looping
either redundantly for a fixed interval of time (for SCHED_NORMAL tasks) or
possibly endlessly (for RT tasks and UP).

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-08 18:25:53 -07:00
Vijay Sampath
83d480917b [MTD] [NOR] Fix oops in cfi_amdstd_sync
The files cfi_cmdset_0002.c and cfi_cmdset_0020.c do not initialize their
wait queues like is done in cfi_cmdset_0001.c.  This causes an oops when
the wait queue is accessed.  I have copied the code from cfi_cmdset_0001.c
that is pertinent to initialization of the wait queue.

Signed-off-by: Vijay Sampath <vsampath@gmail.com>
Acked-by: Joern Engel <joern@lazybastard.org>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2007-03-08 09:22:38 +00:00
Artem Bityutskiy
992c9d24c4 [MTD] [NOR] STAA: use writesize instead off eccsize to represent ECC block
The cfi_staa_write_buffers() uses mtd->eccsize but means mtd->writesize.
BTW, mtd-eccsize is broken and is not initialized, which means the code
fixed by this patch is broken/unused anyway.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2007-02-09 15:26:10 +00:00
Burman Yan
95b93a0cd4 [MTD] replace kmalloc+memset with kzalloc
Signed-off-by: Yan Burman <yan_952@hotmail.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-11-28 23:47:21 +00:00
Joern Engel
5fa433942b [MTD] Introduce MTD_BIT_WRITEABLE
o Add a flag MTD_BIT_WRITEABLE for devices that allow single bits to be
  cleared.
o Replace MTD_PROGRAM_REGIONS with a cleared MTD_BIT_WRITEABLE flag for
  STMicro and Intel Sibley flashes with internal ECC.  Those flashes
  disallow clearing of single bits, unlike regular NOR flashes, so the
  new flag models their behaviour better.
o Remove MTD_ECC.  After the STMicro/Sibley merge, this flag is only set
  and never checked.

Signed-off-by: Joern Engel <joern@wh.fh-wedel.de>
2006-05-22 23:18:29 +02:00
Joern Engel
c8b229de2b [MTD] Merge STMicro NOR_ECC code with Intel Sibley code
In 2002, STMicro started producing NOR flashes with internal ECC protection
for small blocks (8 or 16 bytes).  Support for those flashes was added by me.
In 2005, Intel Sibley flashes copied this strategy and Nico added support for
those.  Merge the code for both.

Signed-off-by: Joern Engel <joern@wh.fh-wedel.de>
2006-05-22 23:18:12 +02:00
David Woodhouse
83ea4ef213 Export cfi_cmdset_0020 and cfi_cmdset_0002 with EXPORT_SYMBOL_GPL
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-05-08 22:58:25 +01:00
David Woodhouse
a15bdeef10 Remove use of inter_module_crap in NOR flash chip drivers.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-05-08 22:35:05 +01:00
Olaf Hering
733482e445 [PATCH] changing CONFIG_LOCALVERSION rebuilds too much, for no good reason
This patch removes almost all inclusions of linux/version.h.  The 3
#defines are unused in most of the touched files.

A few drivers use the simple KERNEL_VERSION(a,b,c) macro, which is
unfortunatly in linux/version.h.

There are also lots of #ifdef for long obsolete kernels, this was not
touched.  In a few places, the linux/version.h include was move to where
the LINUX_VERSION_CODE was used.

quilt vi `find * -type f -name "*.[ch]"|xargs grep -El '(UTS_RELEASE|LINUX_VERSION_CODE|KERNEL_VERSION|linux/version.h)'|grep -Ev '(/(boot|coda|drm)/|~$)'`

search pattern:
/UTS_RELEASE\|LINUX_VERSION_CODE\|KERNEL_VERSION\|linux\/\(utsname\|version\).h

Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:55:57 -08:00
Thomas Gleixner
c2965f1129 [MTD] chips: Clean up trailing white spaces
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-11-07 15:25:34 +01:00
Thomas Gleixner
1f948b43f7 [MTD] chips: Clean up trailing white spaces
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-11-07 14:45:15 +01:00
Todd Poynor
d88f977b85 [MTD] CHIPS: Recognize Spansion CFI 1.4 chips
Modify Amd/Fujitsu CFI NOR flash primary vendor extension table revision
check to recognize version 1.4.  Verified the existing driver can
handle version 1.4 chips without additional info from 1.4 extended table.

Move the primary vendor extension table revision check from common file
to the 3 CFI chip driver files, since the data structures and revisions
handled by those data structures are specific to the chip driver.

Modify the error message printed when the revision is unknown to be a
KERN_ERR instead of WARNING since this will cause mtd to ignore the chip.

Signed-off-by: Todd Poynor <tpoynor@mvista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-08-04 12:49:25 +02:00
Joern Engel
6a8b4d319c [MTD] cfi_cmdset_0002: Plugged a mem leak.
Signed-off-by: Joern Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-07-13 19:04:04 +02:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00