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path: root/drivers/mtd/mtdcore.c
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2012-12-10Revert "revert "Revert "mm: remove __GFP_NO_KSWAPD""" and associated damageLinus Torvalds
This reverts commits a50915394f1fc02c2861d3b7ce7014788aa5066e and d7c3b937bdf45f0b844400b7bf6fd3ed50bac604. 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>
2012-11-30revert "Revert "mm: remove __GFP_NO_KSWAPD""Andrew Morton
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>
2012-11-27Revert "mm: remove __GFP_NO_KSWAPD"Mel Gorman
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>
2012-10-09Merge tag 'disintegrate-mtd-20121009' of ↵David Woodhouse
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
2012-10-09mm: remove __GFP_NO_KSWAPDRik van Riel
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>
2012-09-29mtd: check for max_bitflips in mtd_read_oob()Brian Norris
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>
2012-07-06mtd: move mtd_read_oob() definition out of mtd.hBrian Norris
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>
2012-05-14mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEANMike Dunn
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>
2012-05-14mtd: bitflip_threshold added to mtd_info and sysfsMike Dunn
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>
2012-05-14mtd: expose ecc_strength through sysfsMike Dunn
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>
2012-03-27mtd: unify initialization of erase_info->fail_addrShmulik Ladkani
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>
2012-03-26mtd: check for zero length in OTP functionsArtem Bityutskiy
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>
2012-03-26mtd: move zero length verification to MTD API functionsArtem Bityutskiy
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>
2012-03-26mtd: harmonize mtd_point interface implementationArtem Bityutskiy
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>
2012-03-26mtd: remove retlen zeroing duplicationArtem Bityutskiy
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>
2012-03-26mtd: remove R/O checking duplicationArtem Bityutskiy
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>
2012-03-26mtd: add offset and length checks to the API functionArtem Bityutskiy
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>
2012-03-26mtd: mtdcore: remove unnecessary mtd->resume checkBrian Norris
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>
2012-03-26mtd: add leading underscore to all mtd functionsArtem Bityutskiy
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>
2012-03-26mtd: mtdcore: Fix build warning when CONFIG_MTD_CHAR is not definedFabio Estevam
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>
2012-01-30mtd: fix MTD suspendArtem Bityutskiy
Commits 3fe4bae88460869a8e553397cd9057a4ee7ca341 and 079c985e7a6f4ce60f931cebfdd5ee3c3 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>
2012-01-09mtd: do not use mtd->suspend and mtd->resume directlyArtem Bityutskiy
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>
2012-01-09mtd: do not use mtd->lock, unlock and is_locked directlyArtem Bityutskiy
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>
2012-01-09mtd: harmonize mtd_writev usageArtem Bityutskiy
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>
2012-01-09mtd: mtdcore: export symbols cleanupArtem Bityutskiy
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>
2012-01-09mtd: clean-up the default_mtd_writev functionArtem Bityutskiy
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>
2012-01-09mtd: kill dev_to_mtd helperArtem Bityutskiy
... since it is not needed because the generic 'dev_get_drvdata()' can be used instead. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09mtd: introduce mtd_resume interfaceArtem Bityutskiy
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09mtd: introduce mtd_suspend interfaceArtem Bityutskiy
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09mtd: introduce mtd_unlock interfaceArtem Bityutskiy
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09mtd: introduce mtd_write interfaceArtem Bityutskiy
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-09-11mtd: check parts pointer before using itJason Liu
The code has the check for parts but it called after kmemdup, kmemdup(parts, sizeof(*parts) * nr_parts,...) if (!parts) return -ENOMEM In fact, we need check parts before safely using it. and we also need check the real_parts to make sure kmemdup allocation sucessfully. Signed-off-by: Jason Liu <jason.hui@linaro.org> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11mtd: spelling fixesBrian Norris
Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11mtd: replace DEBUG() with pr_debug()Brian Norris
Start moving away from the MTD_DEBUG_LEVEL messages. The dynamic debugging feature is a generic kernel feature that provides more flexibility. (See Documentation/dynamic-debug-howto.txt) Also fix some punctuation, indentation, and capitalization that went along with the affected lines. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-11mtd: drop mtd_device_registerDmitry Eremin-Solenikov
mtd_device_register() is a limited version of mtd_device_parse_register. Replace it with macro calling mtd_device_parse_register(). Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-09-11mtd: abstract last MTD partition parser argumentDmitry Eremin-Solenikov
Encapsulate last MTD partition parser argument into a separate structure. Currently it holds only 'origin' field for RedBoot parser, but will be extended in future to contain at least device_node for OF devices. Amended commentary to make kerneldoc happy Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Signed-off-by: Artem Bityutskiy <dedekind1@gmail.com>
2011-09-11mtd: add new API for handling MTD registrationDmitry Eremin-Solenikov
Lots (nearly all) mtd drivers contain nearly the similar code that calls parse_mtd_partitions, provides some platform-default values, if parsing fails, and registers mtd device. This is an aim to provide single implementation of this scenario: mtd_device_parse_register() which will handle all this parsing and defaults. Artem: amended comments Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-25mtd: remove add_mtd_partitions, add_mtd_device and friendsJamie Iles
These symbols are replaced with mtd_device_register() (and removal with mtd_device_unregister()) for public registration. Signed-off-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25mtd: introduce mtd_device_(un)register()Jamie Iles
To prepare for the removal of add_mtd_device and add_mtd_partitions(), introduce mtd_device_register(). This will create partitions if they are supplied or register the whole device if there are no partitions. Once all drivers are converted to use mtd_device_register(), add_mtd_device() and add_mtd_partitions() will be made internal only. v2: move kerneldoc to implementation file and fixup some kerneldoc warnings. Artem: tweak comments: remove junk tabs, use dots consistently. Signed-off-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25mtd:fix the bad format in the mtdcore.cWanlong Gao
Remove the spare spaces in the head of the lines. Signed-off-by: Wanlong Gao <wanlong.gao@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25mtd: simplify get_mtd_device_nm functionWanlong Gao
'get_mtd_device_nm()' has a piece of code which equivalent to what '__get_mtd_device()' does - remove this duplicated code and use ''__get_mtd_device()' instead. Artem: changed commit message. Artem: while on it, remove an unnecessary extra empty line Signed-off-by: Wanlong Gao <wanlong.gao@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25mtd: convert to seq_file interfaceAlexey Dobriyan
->read_proc interface is going away, switch to seq_file. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-05-25mtd: create function to perform large allocationsGrant Erickson
Introduce a common function to handle large, contiguous kmalloc buffer allocations by exponentially backing off on the size of the requested kernel transfer buffer until it succeeds or until the requested transfer buffer size falls below the page size. This helps ensure the operation can succeed under low-memory, highly- fragmented situations albeit somewhat more slowly. Artem: so this patch solves the problem that the kernel tries to kmalloc too large buffers, which (a) may fail and does fail - people complain about this, and (b) slows down the system in case of high memory fragmentation, because the kernel starts dropping caches, writing back, swapping, etc. But we do not really have to allocate a lot of memory to do the I/O, we may do this even with as little as one min. I/O unit (NAND page) of RAM. So the idea of this patch is that if the user asks to read or write a lot, we try to kmalloc a lot, with GFP flags which make the kernel _not_ drop caches, etc. If we can allocate it - good, if not - we try to allocate twice as less, and so on, until we reach the min. I/O unit size, which is our last resort allocation and use the normal GFP_KERNEL flag. Artem: re-write the allocation function so that it makes sure the allocated buffer is aligned to the min. I/O size of the flash. Signed-off-by: Grant Erickson <marathon96@gmail.com> Tested-by: Ben Gardiner <bengardiner@nanometrics.ca> Tested-by: Stefano Babic <sbabic@denx.de> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11mtd: local symbols should be staticH Hartley Sweeten
The three backing_dev_info symbols are only used in this file and should be static. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-08-08mtd: Remove obsolete <mtd/compatmac.h> includeDavid Woodhouse
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-08-08mtd: Update copyright noticesDavid Woodhouse
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2010-05-19mtd: update gfp/slab.h includesTejun Heo
Implicit slab.h inclusion via percpu.h is about to go away. Make sure gfp.h or slab.h is included as necessary. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2010-05-10Merge branch 'master' of ↵David Woodhouse
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: drivers/mtd/mtdcore.c Pull in the bdi fixes and ARM platform changes that other outstanding patches depend on.
2010-04-27mtd: ensure that bdi entries are properly initialized and registeredJens Axboe
They will be holding dirty inodes and be responsible for flushing them out, so they need to be setup properly. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-27Move mtd_bdi_*mappable to mtdcore.cJörn Engel
Removes one .h and one .c file that are never used outside of mtdcore.c. Signed-off-by: Joern Engel <joern@logfs.org> Edited to remove on leftover debug define. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>