Commit Graph

113 Commits

Author SHA1 Message Date
Dan Ehrenberg 727dc612c4 mtd: part: Create the master device node when partitioned
For many use cases, it helps to have a device node for the entire
MTD device as well as device nodes for the individual partitions.
For example, this allows querying the entire device's properties.
A common idiom is to create an additional partition which spans
over the whole device.

This patch makes a config option, CONFIG_MTD_PARTITIONED_MASTER,
which makes the master partition present even when the device is
partitioned. This isn't turned on by default since it presents
a backwards-incompatible device numbering.

The patch also makes the parent of a partition device be the master,
if the config flag is set, now that the master is a full device.

Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-04-05 17:44:01 -07:00
Linus Torvalds 402521b8f7 MTD updates for 3.20-rc1
NAND:
 
  * Add new Hisilicon NAND driver for Hip04
  * Add default reboot handler, to ensure all outstanding erase transactions
    complete in time
  * jz4740: convert to use GPIO descriptor API
  * Atmel: add support for sama5d4
  * Change default bitflip threshold to 75% of correction strength
  * Miscellaneous cleanups and bugfixes
 
 SPI NOR:
 
  * Freescale QuadSPI:
    - Fix a few probe() and remove() issues
    - Add a MAINTAINERS entry for this driver
    - Tweak transfer size to increase read performance
    - Add suspend/resume support
  * Add Micron quad I/O support
  * ST FSM SPI: miscellaneous fixes
 
 JFFS2:
 
  * gracefully handle corrupted 'offset' field found on flash
 
 Other:
 
  * bcm47xxpart: add tweaks for a few new devices
  * mtdconcat: set return lengths properly for mtd_write_oob()
  * map_ram: enable use with mtdoops
  * maps: support fallback to ROM/UBI for write-protected NOR flash
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Merge tag 'for-linus-20150216' of git://git.infradead.org/linux-mtd

Pull MTD updates from Brian Norris:
 "NAND:

   - Add new Hisilicon NAND driver for Hip04
   - Add default reboot handler, to ensure all outstanding erase
     transactions complete in time
   - jz4740: convert to use GPIO descriptor API
   - Atmel: add support for sama5d4
   - Change default bitflip threshold to 75% of correction strength
   - Miscellaneous cleanups and bugfixes

  SPI NOR:

   - Freescale QuadSPI:
   - Fix a few probe() and remove() issues
   - Add a MAINTAINERS entry for this driver
   - Tweak transfer size to increase read performance
   - Add suspend/resume support
   - Add Micron quad I/O support
   - ST FSM SPI: miscellaneous fixes

  JFFS2:

   - gracefully handle corrupted 'offset' field found on flash

  Other:

   - bcm47xxpart: add tweaks for a few new devices
   - mtdconcat: set return lengths properly for mtd_write_oob()
   - map_ram: enable use with mtdoops
   - maps: support fallback to ROM/UBI for write-protected NOR flash"

* tag 'for-linus-20150216' of git://git.infradead.org/linux-mtd: (46 commits)
  mtd: hisilicon: && vs & typo
  jffs2: fix handling of corrupted summary length
  mtd: hisilicon: add device tree binding documentation
  mtd: hisilicon: add a new NAND controller driver for hisilicon hip04 Soc
  mtd: avoid registering reboot notifier twice
  mtd: concat: set the return lengths properly
  mtd: kconfig: replace PPC_OF with PPC
  mtd: denali: remove unnecessary stubs
  mtd: nand: remove redundant local variable
  MAINTAINERS: add maintainer entry for FREESCALE QUAD SPI driver
  mtd: fsl-quadspi: improve read performance by increase AHB transfer size
  mtd: fsl-quadspi: Remove unnecessary 'map_failed' label
  mtd: fsl-quadspi: Remove unneeded success/error messages
  mtd: fsl-quadspi: Fix the error paths
  mtd: nand: omap: drop condition with no effect
  mtd: nand: jz4740: Convert to GPIO descriptor API
  mtd: nand: Request strength instead of bytes for soft BCH
  mtd: nand: default bitflip-reporting threshold to 75% of correction strength
  mtd: atmel_nand: introduce a new compatible string for sama5d4 chip
  mtd: atmel_nand: return max bitflips in all sectors in pmecc_correction()
  ...
2015-02-18 08:01:44 -08:00
Niklas Cassel e1dd8641c8 mtd: avoid registering reboot notifier twice
Calling mtd_device_parse_register with the same mtd_info
(e.g. registering several partitions on a single device)
would add the same reboot notifier twice, causing an
infinte loop in notifier_chain_register during boot up.

Signed-off-by: Niklas Cassel <nks@flawful.org>
[Brian: add FIXME comments]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-02-07 22:55:47 -08:00
Arnd Bergmann 706a4e5a12 mtd: export new mtd_mmap_capabilities
The recently added mtd_mmap_capabilities can be used from loadable
modules, in particular romfs, but is not exported, so we get

ERROR: "mtd_mmap_capabilities" [fs/romfs/romfs.ko] undefined!

This adds the missing export.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: b4caecd480 ("fs: introduce f_op->mmap_capabilities for nommu mmap support")
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-28 11:09:20 -07:00
Christoph Hellwig b4caecd480 fs: introduce f_op->mmap_capabilities for nommu mmap support
Since "BDI: Provide backing device capability information [try #3]" the
backing_dev_info structure also provides flags for the kind of mmap
operation available in a nommu environment, which is entirely unrelated
to it's original purpose.

Introduce a new nommu-only file operation to provide this information to
the nommu mmap code instead.  Splitting this from the backing_dev_info
structure allows to remove lots of backing_dev_info instance that aren't
otherwise needed, and entirely gets rid of the concept of providing a
backing_dev_info for a character device.  It also removes the need for
the mtd_inodefs filesystem.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-20 14:02:58 -07:00
Brian Norris 3efe41be22 mtd: implement common reboot notifier boilerplate
cfi_cmdset_000{1,2}.c already implement their own reboot notifiers, and
we're going to add one for NAND. Let's put the boilerplate in one place.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Scott Branden <sbranden@broadcom.com>
2015-01-07 17:54:22 -08:00
Brian Norris 5e47212831 mtd: remove dead non-char logic
MTD used to allow compiling out character device support. This was
dropped in the following commit, but some of the accompanying logic was
never dropped:

  commit 660685d9d1
  Author: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
  Date:   Thu Mar 14 13:27:40 2013 +0200

      mtd: merge mtdchar module with mtdcore

The weird logic was flagged by Coverity.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2014-08-19 11:53:08 -07:00
Brian Norris 0c2b4e2144 mtd: correct upper bounds check for mtd_*() APIs
When checking the upper boundary (i.e., whether an address is higher
than the maximum size of the MTD), we should be doing an inclusive check
(greater or equal). For instance, an address of 16MB (0x1000000) on a
16MB device is invalid.

The strengthening of this bounds check is redundant for those which
already have a address+length check and ensure that the length is
non-zero, but let's just fix them all, for completeness.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-08-19 11:53:07 -07:00
Ezequiel Garcia 8471bb73ba mtd: Introduce mtd_block_isreserved()
In addition to mtd_block_isbad(), which checks if a block is bad or
reserved, it's needed to check if a block is reserved only (but not
bad). This commit adds an MTD interface for it, in a similar fashion to
mtd_block_isbad().

While here, fix mtd_block_isbad() so the out-of-bounds checking is done
before the callback check.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-07-08 18:38:16 -07:00
Ezequiel Garcia 990a3af0c2 mtd: Add sysfs attributes to expose the ECC stats fields
These new sysfs device attributes allow us to retrieve the ECC and bad
block stats by poking a sysfs file, which is often more convenient than
using the ioctl.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-07-08 18:37:26 -07:00
Christian Riesch 9a78bc83b4 mtd: Fix the behavior of OTP write if there is not enough room for data
If a write to one time programmable memory (OTP) hits the end of this
memory area, no more data can be written. The count variable in
mtdchar_write() in drivers/mtd/mtdchar.c is not decreased anymore.
We are trapped in the loop forever, mtdchar_write() will never return
in this case.

The desired behavior of a write in such a case is described in [1]:
- Try to write as much data as possible, truncate the write to fit into
  the available memory and return the number of bytes that actually
  have been written.
- If no data could be written at all, return -ENOSPC.

This patch fixes the behavior of OTP write if there is not enough space
for all data:

1) mtd_write_user_prot_reg() in drivers/mtd/mtdcore.c is modified to
   return -ENOSPC if no data could be written at all.
2) mtdchar_write() is modified to handle -ENOSPC correctly. Exit if a
   write returned -ENOSPC and yield the correct return value, either
   then number of bytes that could be written, or -ENOSPC, if no data
   could be written at all.

Furthermore the patch harmonizes the behavior of the OTP memory write
in drivers/mtd/devices/mtd_dataflash.c with the other implementations
and the requirements from [1]. Instead of returning -EINVAL if the data
does not fit into the OTP memory, we try to write as much data as
possible/truncate the write.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/functions/write.html

Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-10 22:42:31 -07:00
Christian Riesch 4b78fc42f3 mtd: Add a retlen parameter to _get_{fact,user}_prot_info
Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Cc: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-10 22:42:28 -07:00
Axel Lin 54c738f694 mtd: convert to use ATTRIBUTE_GROUPS
Use new ATTRIBUTE_GROUPS macro to declare attribute groups.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-01-03 11:22:21 -08:00
Wei Yongjun ca5295f48b mtd: remove duplicated include from mtdcore.c
Remove duplicated include.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:33:12 -08:00
Ezequiel Garcia f83c3838b9 mtd: Move major number definitions to major.h
This patch moves the char and block major number definitions
to major.h to be with the rest of the major numbers.
While doing this, include major.h in the files that need it.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-11-06 23:32:59 -08:00
Huang Shijie f48372465f mtd: add MTD_MLCNANDFLASH case for mtd_type_show()
The current mtd_type_show() misses the MTD_MLCNANDFLASH case.
This patch adds the case for it, and also updates the ABI.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2013-10-27 16:27:06 -07:00
Huang Shijie bf977e3f15 mtd: add a new sys node to show the ecc step size
Add a new sys node to show the ecc step size.
The application then can uses this node to get the ecc step
size.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-08-30 21:37:56 +01:00
Kees Cook 02aa2a3763 drivers: avoid format string in dev_set_name
Calling dev_set_name with a single paramter causes it to be handled as a
format string.  Many callers are passing potentially dynamic string
content, so use "%s" in those cases to avoid any potential accidents,
including wrappers like device_create*() and bdi_register().

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:41 -07:00
Linus Torvalds a637b0d459 - Lots of cleanups from Artem, including deletion of some obsolete drivers
- Support partitions larger than 4GiB in device tree
 - Support for new SPI chips
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Merge tag 'for-linus-20130509' of git://git.infradead.org/linux-mtd

Pull MTD update from David Woodhouse:

 - Lots of cleanups from Artem, including deletion of some obsolete
   drivers

 - Support partitions larger than 4GiB in device tree

 - Support for new SPI chips

* tag 'for-linus-20130509' of git://git.infradead.org/linux-mtd: (83 commits)
  mtd: omap2: Use module_platform_driver()
  mtd: bf5xx_nand: Use module_platform_driver()
  mtd: denali_dt: Remove redundant use of of_match_ptr
  mtd: denali_dt: Change return value to fix smatch warning
  mtd: denali_dt: Use module_platform_driver()
  mtd: denali_dt: Fix incorrect error check
  mtd: nand: subpage write support for hardware based ECC schemes
  mtd: omap2: use msecs_to_jiffies()
  mtd: nand_ids: use size macros
  mtd: nand_ids: improve LEGACY_ID_NAND macro a bit
  mtd: add 4 Toshiba nand chips for the full-id case
  mtd: add the support to parse out the full-id nand type
  mtd: add new fields to nand_flash_dev{}
  mtd: sh_flctl: Use of_match_ptr() macro
  mtd: gpio: Use of_match_ptr() macro
  mtd: gpio: Use devm_kzalloc()
  mtd: davinci_nand: Use of_match_ptr()
  mtd: dataflash: Use of_match_ptr() macro
  mtd: remove h720x flash support
  mtd: onenand: remove OneNAND simulator
  ...
2013-05-09 10:15:46 -07:00
David Howells 0d01ff2583 Include missing linux/slab.h inclusions
Include missing linux/slab.h inclusions where the source file is currently
expecting to get kmalloc() and co. through linux/proc_fs.h.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: linux-s390@vger.kernel.org
cc: sparclinux@vger.kernel.org
cc: linux-efi@vger.kernel.org
cc: linux-mtd@lists.infradead.org
cc: devel@driverdev.osuosl.org
cc: x86@kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-29 15:42:01 -04:00
Artem Bityutskiy 660685d9d1 mtd: merge mtdchar module with mtdcore
The MTD subsystem has historically tried to be as configurable as possible. The
side-effect of this is that its configuration menu is rather large, and we are
gradually shrinking it. For example, we recently merged partitions support with
the mtdcore.

This patch does the next step - it merges the mtdchar module to mtdcore. And in
this case this is not only about eliminating too fine-grained separation and
simplifying the configuration menu. This is also about eliminating seemingly
useless kernel module.

Indeed, mtdchar is a module that allows user-space making use of MTD devices
via /dev/mtd* character devices. If users do not enable it, they simply cannot
use MTD devices at all. They cannot read or write the flash contents. Is it a
sane and useful setup? I believe not. And everyone just enables mtdchar.

Having mtdchar separate is also a little bit harmful. People sometimes miss the
fact that they need to enable an additional configuration option to have
user-space MTD interfaces, and then they wonder why on earth the kernel does
not allow using the flash? They spend time asking around.

Thus, let's just get rid of this module and make it part of mtd core.

Note, mtdchar had additional configuration option to enable OTP interfaces,
which are present on some flashes. I removed that option as well - it saves a
really tiny amount space.

[dwmw2: Strictly speaking, you can mount file systems on MTD devices just
        fine without the mtdchar (or mtdblock) devices; you just can't do
        other manipulations directly on the underlying device. But still I
        agree that it makes sense to make this unconditional. And Yay! we
        get to kill off an instance of checking CONFIG_foo_MODULE, which is
        an abomination that should never happen.]

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-04-05 13:16:54 +01:00
Artem Bityutskiy 93e562141a mtd: mtdcore: remove few useless #ifdef's
Remove a couple of useles '#ifdef CONFIG_PROC_FS's around procfs functions
which anyway turn into empty function in 'proc_fs.h' file when CONFIG_PROC_FS
is not defined.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-04-05 13:15:31 +01:00
Artem Bityutskiy 26a4734623 mtd: add 'const' qualifier to a couple of register functions
'mtd_device_parse_register()' and 'parse_mtd_partitions()' functions accept a
an array of character pointers. These functions modify neither the pointers nor
the characters they point to. The characters are actually names of the MTD
parsers.

At the moment, the argument type is 'const char **', which means that only the
names of the parsers are constant. Let's turn the argument type into 'const
char * const *', which means that both names and the pointers which point to
them are constant.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-04-05 13:02:16 +01:00
Tejun Heo 589e9c4dac mtd: convert to idr_alloc()
Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.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>
2013-02-27 19:10:18 -08:00
Linus Torvalds caf491916b Revert "revert "Revert "mm: remove __GFP_NO_KSWAPD""" and associated damage
This reverts commits a50915394f and
d7c3b937bd.

This is a revert of a revert of a revert.  In addition, it reverts the
even older i915 change to stop using the __GFP_NO_KSWAPD flag due to the
original commits in linux-next.

It turns out that the original patch really was bogus, and that the
original revert was the correct thing to do after all.  We thought we
had fixed the problem, and then reverted the revert, but the problem
really is fundamental: waking up kswapd simply isn't the right thing to
do, and direct reclaim sometimes simply _is_ the right thing to do.

When certain allocations fail, we simply should try some direct reclaim,
and if that fails, fail the allocation.  That's the right thing to do
for THP allocations, which can easily fail, and the GPU allocations want
to do that too.

So starting kswapd is sometimes simply wrong, and removing the flag that
said "don't start kswapd" was a mistake.  Let's hope we never revisit
this mistake again - and certainly not this many times ;)

Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-10 11:03:05 -08:00
Andrew Morton a50915394f revert "Revert "mm: remove __GFP_NO_KSWAPD""
It apepars that this patch was innocent, and we hope that "mm: avoid
waking kswapd for THP allocations when compaction is deferred or
contended" will fix the final kswapd-spinning cause.

Cc: Zdenek Kabelac <zkabelac@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robert Jennings <rcj@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-30 08:51:17 -08:00
Mel Gorman 82b212f400 Revert "mm: remove __GFP_NO_KSWAPD"
With "mm: vmscan: scale number of pages reclaimed by reclaim/compaction
based on failures" reverted, Zdenek Kabelac reported the following

  Hmm,  so it's just took longer to hit the problem and observe
  kswapd0 spinning on my CPU again - it's not as endless like before -
  but still it easily eats minutes - it helps to	turn off  Firefox
  or TB  (memory hungry apps) so kswapd0 stops soon - and restart
  those apps again.  (And I still have like >1GB of cached memory)

  kswapd0         R  running task        0    30      2 0x00000000
  Call Trace:
    preempt_schedule+0x42/0x60
    _raw_spin_unlock+0x55/0x60
    put_super+0x31/0x40
    drop_super+0x22/0x30
    prune_super+0x149/0x1b0
    shrink_slab+0xba/0x510

The sysrq+m indicates the system has no swap so it'll never reclaim
anonymous pages as part of reclaim/compaction.  That is one part of the
problem but not the root cause as file-backed pages could also be
reclaimed.

The likely underlying problem is that kswapd is woken up or kept awake
for each THP allocation request in the page allocator slow path.

If compaction fails for the requesting process then compaction will be
deferred for a time and direct reclaim is avoided.  However, if there
are a storm of THP requests that are simply rejected, it will still be
the the case that kswapd is awake for a prolonged period of time as
pgdat->kswapd_max_order is updated each time.  This is noticed by the
main kswapd() loop and it will not call kswapd_try_to_sleep().  Instead
it will loopp, shrinking a small number of pages and calling
shrink_slab() on each iteration.

The temptation is to supply a patch that checks if kswapd was woken for
THP and if so ignore pgdat->kswapd_max_order but it'll be a hack and not
backed up by proper testing.  As 3.7 is very close to release and this
is not a bug we should release with, a safer path is to revert "mm:
remove __GFP_NO_KSWAPD" for now and revisit it with the view to ironing
out the balance_pgdat() logic in general.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Zdenek Kabelac <zkabelac@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-26 17:41:24 -08:00
David Woodhouse ffe3150125 UAPI Disintegration 2012-10-09
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Merge tag 'disintegrate-mtd-20121009' of git://git.infradead.org/users/dhowells/linux-headers

UAPI Disintegration 2012-10-09

Conflicts:
	MAINTAINERS
	arch/arm/configs/bcmring_defconfig
	arch/arm/mach-imx/clk-imx51-imx53.c
	drivers/mtd/nand/Kconfig
	drivers/mtd/nand/bcm_umi_nand.c
	drivers/mtd/nand/nand_bcm_umi.h
	drivers/mtd/nand/orion_nand.c
2012-10-09 15:04:25 +01:00
Rik van Riel c654345924 mm: remove __GFP_NO_KSWAPD
When transparent huge pages were introduced, memory compaction and swap
storms were an issue, and the kernel had to be careful to not make THP
allocations cause pageout or compaction.

Now that we have working compaction deferral, kswapd is smart enough to
invoke compaction and the quadratic behaviour around isolate_free_pages
has been fixed, it should be safe to remove __GFP_NO_KSWAPD.

[minchan@kernel.org: Comment fix]
[mgorman@suse.de: Avoid direct reclaim for deferred compaction]
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:22:15 +09:00
Brian Norris e47f68587b mtd: check for max_bitflips in mtd_read_oob()
mtd_read_oob() has some unexpected similarities to mtd_read(). For
instance, when ops->datbuf != NULL, nand_base.c might return max_bitflips;
however, when ops->datbuf == NULL, nand_base's code potentially could
return -EUCLEAN (no in-tree drivers do this yet). In any case where the
driver might return max_bitflips, we should translate this into an
appropriate return code using the bitflip_threshold.

Essentially, mtd_read_oob() duplicates the logic from mtd_read().

This prevents users of mtd_read_oob() from receiving a positive return
value (i.e., from max_bitflips) and interpreting it as an unknown error.

Artem: amend comments.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Mike Dunn <mikedunn@newsguy.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-09-29 14:50:50 +01:00
Brian Norris d2d48480d1 mtd: move mtd_read_oob() definition out of mtd.h
mtd_read_oob() will be expanded a little, so don't leave it in the header
as a static inline function.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-06 18:16:24 +01:00
Mike Dunn edbc4540e0 mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN
The drivers' _read() method, absent an error, returns a non-negative integer
indicating the maximum number of bit errors that were corrected in any one
region comprising an ecc step.  MTD returns -EUCLEAN if this is >=
bitflip_threshold, 0 otherwise.  If bitflip_threshold is zero, the comparison is
not made since these devices lack ECC and always return zero in the non-error
case (thanks Brian)¹.  Note that this is a subtle change to the driver
interface.

This and the preceding patches in this set were tested with ubi on top of the
nandsim and docg4 devices, running the ubi test io_basic from mtd-utils.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-March/040468.html

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Ivan Djelic <ivan.djelic@parrot.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-05-13 23:14:23 -05:00
Mike Dunn d062d4ede8 mtd: bitflip_threshold added to mtd_info and sysfs
An element 'bitflip_threshold' is added to struct mtd_info, and also exposed as
a read/write variable in sysfs.  This will be used to determine whether or not
mtd_read() returns -EUCLEAN or 0 (absent a hard error).  If the driver leaves it
as zero, mtd will set it to a default value of ecc_strength.

This v2 adds the line that propagates bitflip_threshold from the master to the
partitions - thanks Ivan¹.

¹ http://lists.infradead.org/pipermail/linux-mtd/2012-April/040900.html

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-05-13 23:11:39 -05:00
Mike Dunn a9b672e82b mtd: expose ecc_strength through sysfs
ecc_strength element of struct mtd_info is exposed as a read-only variable in
sysfs.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-05-13 23:10:45 -05:00
Shmulik Ladkani 3b27dac039 mtd: unify initialization of erase_info->fail_addr
Initialization of 'erase_info->fail_addr' to MTD_FAIL_ADDR_UNKNOWN prior
erase operation is duplicated accross several MTD drivers, and also taken
care of by some MTD users as well.

Harmonize it: initialize 'fail_addr' within 'mtd_erase()' interface.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 01:02:24 +01:00
Artem Bityutskiy de3cac9357 mtd: check for zero length in OTP functions
This patch changes all the OTP functions like 'mtd_get_fact_prot_info()' and
makes them return zero immediately if the input 'len' parameter is 0. This is
not really needed currently, but most of the other functions do this, and it is
just consistent to do the same in the OTP functions.

This patch also moves the OTP functions from the header file to mtdcore.c
because they become a bit too big for being inlined.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:32:29 +01:00
Artem Bityutskiy bcb1d23871 mtd: move zero length verification to MTD API functions
In many places in drivers we verify for the zero length, but this is very
inconsistent across drivers. This is obviously the right thing to do, though.
This patch moves the check to the MTD API functions instead and removes a lot
of duplication.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:32:19 +01:00
Artem Bityutskiy 0dd5235f51 mtd: harmonize mtd_point interface implementation
Some MTD drivers return -EINVAL if the 'phys' parameter is not NULL, trying to
convey that they cannot return the physical address. However, this is not very
logical because they still can return the virtual address ('virt'). But some
drivers (lpddr) just ignore the 'phys' parameter instead, which is a more
logical thing to do.

Let's harmonize this and:

1. Always initialize 'virt' and 'phys' to 'NULL' in 'mtd_point()'.
2. Do not return an error if the physical address cannot be found.

So as a result, all drivers will set 'phys' to 'NULL' if it is not supported.
None of the 'mtd_point()' users use 'phys' anyway, so this should not break
anything. I guess we could also just delete this parameter later.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:32:11 +01:00
Artem Bityutskiy 834247ec7e mtd: remove retlen zeroing duplication
The MTD API function now zero the 'retlen' parameter before calling
the driver's method — do not do this again in drivers. This removes
duplicated '*retlen = 0' assignent from the following methods:

    'mtd_point()'
    'mtd_read()'
    'mtd_write()'
    'mtd_writev()'
    'mtd_panic_write()'

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:29:34 +01:00
Artem Bityutskiy 664addc248 mtd: remove R/O checking duplication
Many drivers check whether the partition is R/O and return -EROFS if yes.
Let's stop having duplicated checks and move them to the API functions
instead.

And again a bit of noise - deleted few too sparse newlines, sorry.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:29:11 +01:00
Artem Bityutskiy 8273a0c911 mtd: add offset and length checks to the API function
Add verification of the offset and length to MTD API functions and verify that
MTD device offset and length are within MTD device size.

The modified API functions are:

'mtd_erase()'
'mtd_point()'
'mtd_unpoint()'
'mtd_get_unmapped_area()'
'mtd_read()'
'mtd_write()'
'mtd_panic_write()'
'mtd_lock()'
'mtd_unlock()'
'mtd_is_locked()'
'mtd_block_isbad()'
'mtd_block_markbad()'

This patch also uninlines these functions and exports in mtdcore.c because they
are not performance-critical and do not have to be inlined.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:28:05 +01:00
Brian Norris 3ee5014185 mtd: mtdcore: remove unnecessary mtd->resume check
We don't need to to check for mtd->resume before calling mtd_resume().
mtd_resume() should take care of that.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:20:18 +01:00
Artem Bityutskiy 3c3c10bba1 mtd: add leading underscore to all mtd functions
This patch renames all MTD functions by adding a "_" prefix:

mtd->erase -> mtd->_erase
mtd->read_oob -> mtd->_read_oob
...

The reason is that we are re-working the MTD API and from now on it is
an error to use MTD function pointers directly - we have a corresponding
API call for every pointer. By adding a leading "_" we achieve the following:

1. Make sure we convert every direct pointer users
2. A leading "_" suggests that this interface is internal and it becomes
   less likely that people will use them directly
3. Make sure all the out-of-tree modules stop compiling and the owners
   spot the big API change and amend them.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:20:01 +01:00
Fabio Estevam 335a5f409e mtd: mtdcore: Fix build warning when CONFIG_MTD_CHAR is not defined
Fix the following build warning:

drivers/mtd/mtdcore.c: In function ‘mtd_release’:
drivers/mtd/mtdcore.c:110: warning: unused variable ‘mtd’

This happens when neither CONFIG_MTD_CHAR nor CONFIG_MTD_CHAR_MODULE are defined.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-03-27 00:11:16 +01:00
Artem Bityutskiy 1a30871fe6 mtd: fix MTD suspend
Commits 3fe4bae884 and
079c985e7a broke MTD suspend in 2 ways:

1. When the '->suspend' method is not present, we return -EOPNOTSUPP, but
   the callers of 'mtd_suspend()' expects 0 instead.
2. Checking of the 'mtd' parameter against NULL has been incorrectly removed
   in 'mtd_cls_suspend()'.

This patch fixes the breakages. This has been found, analyzed, reported
and tested by Rafael J. Wysocki <rjw@sisk.pl>.

Note, this patch is not needed in the stable tree because it causes a
regression introduced during the v3.3 merge window.

Reported-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-30 14:23:07 +00:00
Artem Bityutskiy 079c985e7a mtd: do not use mtd->suspend and mtd->resume directly
Just call the 'mtd_suspend()' and 'mtd_resume()' - they will do nothing
if the operation is not defined.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:23 +00:00
Artem Bityutskiy 381345652f mtd: do not use mtd->lock, unlock and is_locked directly
Instead, call the corresponding MTD API function which will return
'-EOPNOTSUPP' if the operation is not supported.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:22 +00:00
Artem Bityutskiy 1dbebd3256 mtd: harmonize mtd_writev usage
This patch makes the 'mtd_writev()' function more usable and logical. We first
teach it to fall-back to the 'default_mtd_writev()' function if the MTD driver
does not define its own '->writev()' method. Then we make block2mtd and JFFS2
just 'mtd_writev()' instead of 'default_mtd_writev()' function. This means we
can now stop exporting 'default_mtd_writev()' and instead, export
'mtd_writev()'. This is much cleaner and more logical, as well as allows us to
get read of another direct 'mtd->writev' access in JFFS2.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:19 +00:00
Artem Bityutskiy 33c87b4a2c mtd: mtdcore: export symbols cleanup
The mtdcore.c file is a bit inconsistent - some EXPORT_SYMBOL_GPL declarations
follow the corresponding functions, some are placed at the end. This patch
harmonizes the file so that EXPORT_SYMBOL_GPL declarations follow the
corresponding function.

It also removes few extra newlines and trailing white-spaces.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:06 +00:00
Artem Bityutskiy 52b020317f mtd: clean-up the default_mtd_writev function
1. Teach 'mtd_write()' function to return '-EROFS' if the write method
   is undefined, and remove the corresponding check from
   'default_mtd_writev()'.
2. Do not test 'retlen' for NULL - it cannot be NULL.
3. Few minor coding stile clean-ups.
4. Add a kerneldoc comment

Additionally, minor fixes to the kerneldoc comments of the neighbor function.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:26:05 +00:00