Commit Graph

209 Commits

Author SHA1 Message Date
Boris Brezillon 884cfd9023 mtd: Stop assuming mtd_erase() is asynchronous
None of the mtd->_erase() implementations work in an asynchronous manner,
so let's simplify MTD users that call mtd_erase(). All they need to do
is check the value returned by mtd_erase() and assume that != 0 means
failure.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
2018-03-15 18:21:07 +01:00
Boris Brezillon c585da9f5f mtd: Initialize ->fail_addr early in mtd_erase()
mtd_erase() can return an error before ->fail_addr is initialized to
MTD_FAIL_ADDR_UNKNOWN. Move this initialization at the very beginning
of the function.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
2018-03-15 17:25:05 +01:00
Rafał Miłecki 0dbe4ea78d mtd: get rid of the mtd_add_device_partitions()
This simplifies code a bit by:
1) Avoiding an extra (tiny) function
2) Checking for amount of parsed (found) partitions just once
3) Avoiding clearing/filling struct mtd_partitions manually

With this commit proper functions are called directly from the
mtd_device_parse_register(). It doesn't need to use minor tricks like
memsetting struct to 0 to trigger an expected
mtd_add_device_partitions() behavior.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-02-12 13:39:20 +01:00
Rafał Miłecki 2c77c57d22 mtd: move code adding master MTD out of mtd_add_device_partitions()
This change is a small cleanup of mtd_device_parse_register(). When
using MTD_PARTITIONED_MASTER it makes sure a master MTD is registered
before dealing with partitions. The advantage of this is not mixing
code handling master MTD with code handling partitions.

This commit doesn't change any behavior except from a slightly different
failure code path. The new code may need to call del_mtd_device when
something goes wrong.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-02-12 13:39:20 +01:00
Boris Brezillon e6e620f0e1 mtd: Make sure the device supports erase operations in mtd_erase()
Some devices do not implement ->_erase() or have an invalid ->erasesize
value. In this case, mtd_erase() should return -ENOTSUPP.

Note that the test is not done on the MTD_NO_ERASE flag because this
flag means 'erasing a block before writing to it is unnecessary',
not 'the erase operation is not supported'. Actually, some drivers are
setting the MTD_NO_ERASE flag but still implementing the ->_erase()
hook and setting a valid ->erasesize value.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-02-12 11:46:38 +01:00
Linus Torvalds 0fc7e74663 MTD changes:
Core changes:
   * Rework core functions to avoid duplicating generic checks in
     NAND/OneNAND sub-layers
   * Update the MAINTAINERS entry to reflect the fact that MTD
     maintainers now use a single git tree
 
   Driver changes:
   * CFI: use macros instead of inline functions to limit stack
     usage and make KASAN happy
 
 NAND changes:
   Core changes:
   * Fix NAND_CMD_NONE handling in nand_command[_lp]() hooks
   * Introduce the ->exec_op() infrastructure
   * Rework NAND buffers handling
   * Fix ECC requirements for K9F4G08U0D
   * Fix nand_do_read_oob() to return the number of bitflips
   * Mark K9F1G08U0E as not supporting subpage writes
 
   Driver changes:
   * MTK: Rework the driver to support new IP versions
   * OMAP OneNAND: Full rework to use new APIs (libgpio, dmaengine) and fix
     DT support
   * Marvell: Add a new driver to replace the pxa3xx one
 
 SPI NOR changes:
   Core changes:
   * Add support to new ISSI and Cypress/Spansion memory parts.
   * Fix support of Micron memories by checking error bits in the FSR.
   * Fix update of block-protection bits by reading back the SR.
   * Restore the internal state of the SPI flash memory when removing the
     device.
 
   Driver changes:
   * Maintenance for Freescale, Intel and Metiatek drivers.
   * Add support of the direct access mode for the Cadence QSPI controller.
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Merge tag 'mtd/for-4.16' of git://git.infradead.org/linux-mtd

Pull MTD updates from Boris Brezillon:
 "MTD core changes:
   - Rework core functions to avoid duplicating generic checks in
     NAND/OneNAND sub-layers
   - Update the MAINTAINERS entry to reflect the fact that MTD
     maintainers now use a single git tree

  MTD driver changes:
   - CFI: use macros instead of inline functions to limit stack usage
     and make KASAN happy

  NAND core changes:
   - Fix NAND_CMD_NONE handling in nand_command[_lp]() hooks
   - Introduce the ->exec_op() infrastructure
   - Rework NAND buffers handling
   - Fix ECC requirements for K9F4G08U0D
   - Fix nand_do_read_oob() to return the number of bitflips
   - Mark K9F1G08U0E as not supporting subpage writes

  NAND driver changes:
   - MTK: Rework the driver to support new IP versions
   - OMAP OneNAND: Full rework to use new APIs (libgpio, dmaengine) and
     fix DT support
   - Marvell: Add a new driver to replace the pxa3xx one

  SPI NOR core changes:
   - Add support to new ISSI and Cypress/Spansion memory parts.
   - Fix support of Micron memories by checking error bits in the FSR.
   - Fix update of block-protection bits by reading back the SR.
   - Restore the internal state of the SPI flash memory when removing
     the device.

  SPI NOR driver changes:
   - Maintenance for Freescale, Intel and Metiatek drivers.
   - Add support of the direct access mode for the Cadence QSPI
     controller"

* tag 'mtd/for-4.16' of git://git.infradead.org/linux-mtd: (93 commits)
  mtd: nand: sunxi: Fix ECC strength choice
  mtd: nand: gpmi: Fix subpage reads
  mtd: nand: Fix build issues due to an anonymous union
  mtd: nand: marvell: Fix missing memory allocation modifier
  mtd: nand: marvell: remove redundant variable 'oob_len'
  mtd: nand: marvell: fix spelling mistake: "suceed"-> "succeed"
  mtd: onenand: omap2: Remove redundant dev_err call in omap2_onenand_probe()
  mtd: Remove duplicate checks on mtd_oob_ops parameter
  mtd: Fallback to ->_read/write_oob() when ->_read/write() is missing
  mtd: mtdpart: Make ECC stat handling consistent
  mtd: onenand: omap2: print resource using %pR format string
  mtd: mtk-nor: modify functions' name more generally
  mtd: onenand: samsung: remove incorrect __iomem annotation
  MAINTAINERS: Add entry for Marvell NAND controller driver
  ARM: OMAP2+: Remove gpmc-onenand
  mtd: onenand: omap2: Configure driver from DT
  mtd: onenand: omap2: Decouple DMA enabling from INT pin availability
  mtd: onenand: omap2: Do not make delay for GPIO OMAP3 specific
  mtd: onenand: omap2: Convert to use dmaengine for memcpy
  mtd: onenand: omap2: Unify OMAP2 and OMAP3 DMA implementation
  ...
2018-01-29 11:11:56 -08:00
Boris Brezillon 24ff129222 mtd: Fallback to ->_read/write_oob() when ->_read/write() is missing
Some MTD sublayers/drivers are implementing ->_read/write_oob() and
provide dummy wrappers for their ->_read/write() implementations.
Let the core handle this case instead of duplicating the logic.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Tested-by: Ladislav Michl <ladis@linux-mips.org>
2018-01-16 15:23:21 +01:00
Boris Brezillon 33f45c44d6 mtd: Do not allow MTD devices with inconsistent erase properties
When mtd->erasesize is 0 or mtd->_erase is NULL, that means the device
does not support the erase operation, which in turn means it should
have the MTD_NO_ERASE flag set.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Miquel Raynal <miquel.raynal@free-electrons.com>
2018-01-06 15:09:40 +01:00
Miquel Raynal d82c368216 mtd: Fix mtd_check_oob_ops()
The mtd_check_oob_ops() helper verifies if the operation defined by the
user is correct.

Fix the check that verifies if the entire requested area exists. This
check is too restrictive and will fail anytime the last data byte of the
very last page is included in an operation.

Fixes: 5cdd929da5 ("mtd: Add sanity checks in mtd_write/read_oob()")
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-12-18 09:16:35 +01:00
Boris Brezillon 5cdd929da5 mtd: Add sanity checks in mtd_write/read_oob()
Unlike what's done in mtd_read/write(), there are no checks to make sure
the parameters passed to mtd_read/write_oob() are consistent, which
forces implementers of ->_read/write_oob() to do it, which in turn leads
to code duplication and possibly errors in the logic.

Do general sanity checks, like ops fields consistency and range checking.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Peter Pan <peterpandong@micron.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-11-13 21:39:19 +01:00
Nicolas Pitre 9eaa903c06 mtd: implement mtd_get_unmapped_area() using the point method
The mtd->_point method is a superset of mtd->_get_unmapped_area.
Especially in the NOR flash case, the point method ensures the flash
memory is in array (data) mode and that it will stay that way which
is precisely what callers of mtd_get_unmapped_area() would expect.

Implement mtd_get_unmapped_area() in terms of mtd->_point now that all
drivers that provided a _get_unmapped_area method also have the _point
method implemented.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Richard Weinberger <richard@nod.at>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-11-13 21:39:18 +01:00
Bhumika Goyal 75864b301c mtd: make device_type const
Make this const as it is only stored in the type field of a device
structure, which is const.
Done using Coccinelle.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2017-08-21 14:33:50 +02:00
Mario Rugiero e8e3edb95c mtd: create per-device and module-scope debugfs entries
Several MTD devices are using debugfs entries created in the root.
This commit provides the means for a standardized subtree, creating
one "mtd" entry at root, and one entry per device inside it, named
after the device.
The tree is registered in add_mtd_device, and released in
del_mtd_device.
Devices docg3, mtdswap and nandsim were updated to use this subtree
instead of custom ones, and their entries were prefixed with the
drivers' names.

Signed-off-by: Mario J. Rugiero <mrugiero@gmail.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2017-07-21 13:25:29 -07:00
Boris Brezillon b9504247a6 mtd: Fix check in mtd_unpoint()
The code checks that ->_point is not NULL, but we should actually check
->_unpoint value which is dereferenced a few lines after the check.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2017-07-07 17:57:59 -07:00
Jan Kara 7c4cc30024 bdi: Drop 'parent' argument from bdi_register[_va]()
Drop 'parent' argument of bdi_register() and bdi_register_va().  It is
always NULL.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:09:55 -06:00
Jan Kara fa06052d63 mtd: Convert to dynamically allocated bdi infrastructure
MTD already allocates backing_dev_info dynamically. Convert it to use
generic infrastructure for this including proper refcounting. We drop
mtd->backing_dev_info as its only use was to pass mtd_bdi pointer from
one file into another and if we wanted to keep that in a clean way, we'd
have to make mtd hold and drop bdi reference as needed which seems
pointless for passing one global pointer...

CC: David Woodhouse <dwmw2@infradead.org>
CC: Brian Norris <computersforpeace@gmail.com>
CC: linux-mtd@lists.infradead.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:09:55 -06:00
Masahiro Yamada 7da0fffb3a mtd: fix typos in ooblayout comment blocks
- "This functions return ..." -> "This function returns ..."
 - "I you want ..." -> "If you want ..."

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2017-02-08 13:32:08 -08:00
Steve Longerbeam 445caaa20c mtd: Allocate bdi objects dynamically
The MTD backing dev info objects mtd_bdi was statically allocated.
So when MTD is built as a loadable module, this object fall in the
vmalloc address space.

The problem with that, is that the BDI APIs use wake_up_bit(), which calls
virt_to_page() to retrieve the memory zone of the page containing the
wait_queue to wake up, and virt_to_page() is not valid for vmalloc or
highmem addresses.

Fix this by allocating the BDI objects dynamically with kmalloc. The
objects now fall in the logical address space so that BDI APIs will
work in all cases (mtd builtin or module).

Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Jim Baxter <jim_baxter@mentor.com>
Signed-off-by: Sandeep Jain <Sandeep_Jain@mentor.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-12-01 10:03:17 -08:00
Masahiro Yamada 4d6aecfb7e mtd: remove unneeded initializer in mtd_ooblayout_count_bytes()
There is no need to initialize oobregion since it will be filled by
the iterator.

This function is called with mtd_ooblayout_free or mtd_ooblayout_ecc
for the iterator; both of them calls memset() to clear the oobregion.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-11-19 19:31:34 +01:00
Masahiro Yamada 7c295ef964 mtd: use min_t() to refactor mtd_ooblayout_{get, set}_bytes()
I hope this will make the code a little more readable.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-11-19 19:31:32 +01:00
Masahiro Yamada 8e8fd4d1e8 mtd: remove unneeded initializer in mtd_ooblayout_{get, set}_bytes()
There is no need to initialize oobregion and section since they will
be filled by mtd_ooblayout_find_region().

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-11-19 19:31:29 +01:00
Masahiro Yamada 97139d4a6f treewide: remove redundant #include <linux/kconfig.h>
Kernel source files need not include <linux/kconfig.h> explicitly
because the top Makefile forces to include it with:

  -include $(srctree)/include/linux/kconfig.h

This commit removes explicit includes except the following:

  * arch/s390/include/asm/facilities_src.h
  * tools/testing/radix-tree/linux/kernel.h

These two are used for host programs.

Link: http://lkml.kernel.org/r/1473656164-11929-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11 15:06:33 -07:00
Boris Brezillon 477b0229ac mtd: introduce the mtd_pairing_scheme concept
MLC and TLC NAND devices are using NAND cells exposing more than one bit,
but instead of attaching all the bits in a given cell to a single NAND
page, each bit is usually attached to a different page. This concept is
called 'page pairing', and has significant impacts on the flash storage
usage.
The main problem showed by these devices is that interrupting a page
program operation may not only corrupt the page we are programming
but also the page it is paired with, hence the need to expose to MTD
users the pairing scheme information.

The pairing APIs allows one to query pairing information attached to a
given page (here called wunit), or the other way around (the wunit
pointed by pairing information).
It also provides several helpers to help the conversion between absolute
offsets and wunits, and query the number of pairing groups.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Brian Norris <computersforpeace@gmail.com>
2016-09-15 16:47:56 +02:00
Boris Brezillon aab616e31d mtd: kill the nand_ecclayout struct
Now that all MTD drivers have moved to the mtd_ooblayout_ops model we can
safely remove the struct nand_ecclayout definition, and all the remaining
places where it was still used.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:51:51 +02:00
Boris Brezillon adbbc3bc82 mtd: create an mtd_ooblayout_ops struct to ease ECC layout definition
ECC layout definitions are currently exposed using the nand_ecclayout
struct which embeds oobfree and eccpos arrays with predefined size.
This approach was acceptable when NAND chips were providing relatively
small OOB regions, but MLC and TLC now provide OOB regions of several
hundreds of bytes, which implies a non negligible overhead for everybody
even those who only need to support legacy NANDs.

Create an mtd_ooblayout_ops interface providing the same functionality
(expose the ECC and oobfree layout) without the need for this huge
structure.

The mtd->ecclayout is now deprecated and should be replaced by the
equivalent mtd_ooblayout_ops. In the meantime we provide a wrapper around
the ->ecclayout field to ease migration to this new model.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-04-19 22:05:55 +02:00
Boris Brezillon 75eb2cec25 mtd: add mtd_ooblayout_xxx() helper functions
In order to make the ecclayout definition completely dynamic we need to
rework the way the OOB layout are defined and iterated.

Create a few mtd_ooblayout_xxx() helpers to ease OOB bytes manipulation
and hide ecclayout internals to their users.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-04-19 22:05:47 +02:00
Ezequiel Garcia fea728c098 mtd: Hook I/O activity to the MTD LED trigger
Now that we've added the MTD LED trigger, we need
to call each I/O path to ledtrig_mtd_activity.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-04-13 10:23:16 +02:00
Ezequiel Garcia 0c034fe377 mtd: Uninline mtd_write_oob and move it to mtdcore.c
There's no reason for having mtd_write_oob inlined in mtd.h header.
Move it to mtdcore.c where it belongs.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-04-13 10:23:14 +02:00
Brian Norris e576330033 mtd: merge MTD development from v4.4 into for-v4.5 development
Small conflict between some bugfixes for 4.4 and some refactoring for
4.5.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-01-05 16:05:56 -08:00
Brian Norris 472b444eef mtd: fix cmdlinepart parser, early naming for auto-filled MTD
Commit 807f16d4db ("mtd: core: set some defaults when dev.parent is
set") attempted to provide some default settings for MTDs that
 (a) assign the parent device and
 (b) don't provide their own name or owner

However, this isn't a perfect drop-in replacement for the boilerplate
found in some drivers, because the MTD name is used by partition
parsers like cmdlinepart, but the name isn't set until add_mtd_device(),
after the parsing is completed. This means cmdlinepart sees a NULL name
and therefore will not work properly.

Fix this by moving the default name and owner assignment to be first in
the MTD registration process.

[Note: this does not fix all reported issues, particularly with NAND
drivers. Will require an additional fix for drivers/mtd/nand/]

Fixes: 807f16d4db ("mtd: core: set some defaults when dev.parent is set")
Reported-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Heiko Schocher <hs@denx.de>
Cc: Frans Klaver <fransklaver@gmail.com>
2016-01-04 10:54:18 -08:00
Brian Norris adc83bf889 mtd: partitions: support a cleanup callback for parsers
If partition parsers need to clean up their resources, we shouldn't
assume that all memory will fit in a single kmalloc() that the caller
can kfree(). We should allow the parser to provide a proper cleanup
routine.

Note that this means we need to keep a hold on the parser's module for a
bit longer, and release it later with mtd_part_parser_put().

Alongside this, define a default callback that we'll automatically use
if the parser doesn't provide one, so we can still retain the old
behavior.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2015-12-09 14:57:44 -08:00
Brian Norris 07fd2f871c mtd: partitions: pass around 'mtd_partitions' wrapper struct
For some of the core partitioning code, it helps to keep info about the
parsed partition (and who parsed them) together in one place.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-12-09 10:22:09 -08:00
Brian Norris c42c2710d6 mtd: partitions: remove kmemdup()
The use of kmemdup() complicates the error handling a bit. We don't
actually need to allocate new memory, since this reference is treated as
const, and it is copied into new memory by the partition registration
code anyway. So remove it.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2015-12-09 10:22:06 -08:00
Brian Norris 617f41836c Linux 4.4-rc1
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Merge v4.4-rc1 into MTD development

Sync up with the upstream development.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-11-15 20:31:29 -08:00
Brian Norris 215a02fd30 mtd: grab a reference to the MTD of_node before registering it
We now stick the device node representing the current MTD (if any) into
sysfs, so let's make sure we have a reference to it before doing that.

Suggested-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2015-11-12 10:09:55 -08:00
Linus Torvalds ad804a0b2a Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton:

 - most of the rest of MM

 - procfs

 - lib/ updates

 - printk updates

 - bitops infrastructure tweaks

 - checkpatch updates

 - nilfs2 update

 - signals

 - various other misc bits: coredump, seqfile, kexec, pidns, zlib, ipc,
   dma-debug, dma-mapping, ...

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (102 commits)
  ipc,msg: drop dst nil validation in copy_msg
  include/linux/zutil.h: fix usage example of zlib_adler32()
  panic: release stale console lock to always get the logbuf printed out
  dma-debug: check nents in dma_sync_sg*
  dma-mapping: tidy up dma_parms default handling
  pidns: fix set/getpriority and ioprio_set/get in PRIO_USER mode
  kexec: use file name as the output message prefix
  fs, seqfile: always allow oom killer
  seq_file: reuse string_escape_str()
  fs/seq_file: use seq_* helpers in seq_hex_dump()
  coredump: change zap_threads() and zap_process() to use for_each_thread()
  coredump: ensure all coredumping tasks have SIGNAL_GROUP_COREDUMP
  signal: remove jffs2_garbage_collect_thread()->allow_signal(SIGCONT)
  signal: introduce kernel_signal_stop() to fix jffs2_garbage_collect_thread()
  signal: turn dequeue_signal_lock() into kernel_dequeue_signal()
  signals: kill block_all_signals() and unblock_all_signals()
  nilfs2: fix gcc uninitialized-variable warnings in powerpc build
  nilfs2: fix gcc unused-but-set-variable warnings
  MAINTAINERS: nilfs2: add header file for tracing
  nilfs2: add tracepoints for analyzing reading and writing metadata files
  ...
2015-11-07 14:32:45 -08:00
Mel Gorman d0164adc89 mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts.  They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve".  __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".

Over time, callers had a requirement to not block when fallback options
were available.  Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.

This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative.  High priority users continue to use
__GFP_HIGH.  __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim.  __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim.  __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.

This patch then converts a number of sites

o __GFP_ATOMIC is used by callers that are high priority and have memory
  pools for those requests. GFP_ATOMIC uses this flag.

o Callers that have a limited mempool to guarantee forward progress clear
  __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
  into this category where kswapd will still be woken but atomic reserves
  are not used as there is a one-entry mempool to guarantee progress.

o Callers that are checking if they are non-blocking should use the
  helper gfpflags_allow_blocking() where possible. This is because
  checking for __GFP_WAIT as was done historically now can trigger false
  positives. Some exceptions like dm-crypt.c exist where the code intent
  is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
  flag manipulations.

o Callers that built their own GFP flags instead of starting with GFP_KERNEL
  and friends now also need to specify __GFP_KSWAPD_RECLAIM.

The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.

The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL.  They may
now wish to specify __GFP_KSWAPD_RECLAIM.  It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Brian Norris f8479dd6a0 mtd: don't WARN about overloaded users of mtd->reboot_notifier.notifier_call
There are multiple types of users of mtd->reboot_notifier.notifier_call:

(1) A while back, the cfi_cmdset_000{1,2} chip drivers implemented a
reboot notifier to (on a best effort basis) attempt to reset their flash
chips before rebooting.

(2) More recently, we implemented a common _reboot() hook so that MTD
drivers (particularly, NAND flash) could better halt I/O operations
without having to reimplement the same notifier boilerplate.

Currently, the WARN_ONCE() condition here was written to handle (2), but
at the same time it mis-diagnosed case (1) as an already-registered MTD.
Let's fix this by having the WARN_ONCE() condition better imitate the
condition that immediately follows it. (Wow, I don't know how I missed
that one.)

(Side note: Unfortunately, we can't yet combine the reboot notifier code
for (1) and (2) with a patch like [1], because some users of (1) also
use mtdconcat, and so the mtd_info struct from cfi_cmdset_000{1,2} won't
actually get registered with mtdcore, and therefore their reboot
notifier won't get registered.)

[1] http://patchwork.ozlabs.org/patch/417981/

Suggested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Jesper Nilsson <jespern@axis.com>
Cc: linux-cris-kernel@axis.com
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-11-06 09:33:15 -08:00
Brian Norris 5a2415b076 mtd: mtdpart: Do not fail mtd probe when parsing partitions fails
Due to wrong assumption in ofpart ofpart fails on Exynos on SPI chips
with no partitions because the subnode containing controller data
confuses the ofpart parser.

Thus compiling in ofpart support automatically fails probing any SPI NOR
flash without partitions on Exynos.

Compiling in a partitioning scheme should not cause probe of otherwise
valid device to fail.

Instead, let's do the following:
 * try parsers until one succeeds
 * if no parser succeeds, report the first error we saw
 * even in the failure case, allow MTD to probe, with fallback
   partitions or no partitions at all -- the master device will still be
   registered

Issue report and comments initially by Michal Suchanek.

Reported-by: Michal Suchanek <hramrach@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-26 18:43:48 -07:00
Brian Norris be0dbff8b4 mtd: warn when registering the same master many times
When CONFIG_MTD_PARTITIONED_MASTER=y, it is fatal to call
mtd_device_parse_register() twice on the same MTD, as we try to register
the same device/kobject multipile times.

When CONFIG_MTD_PARTITIONED_MASTER=n, calling
mtd_device_parse_register() is more of just a nuisance, as we can mostly
navigate around any conflicting actions.

But anyway, doing so is a Bad Thing (TM), and we should complain loudly
for any drivers that try to do this.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
2015-10-26 14:34:07 -07:00
Brian Norris 3e00ed0e98 mtd: fixup corner case error handling in mtd_device_parse_register()
Since commit 3efe41be22 ("mtd: implement common reboot notifier
boilerplate"), we might try to register a reboot notifier for an MTD
that failed to register. Let's avoid this by making the error path
clearer.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
2015-10-26 14:32:33 -07:00
Frans Klaver 807f16d4db mtd: core: set some defaults when dev.parent is set
If a parent device is set, add_mtd_device() has enough knowledge to fill
in some sane default values for the module name and owner. Do so if they
aren't already set.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 09:21:13 -07:00
Frans Klaver 260e89a6e0 mtd: core: tone down suggestion that dev.parent should be set
add_mtd_device() has a comment suggesting that the caller should have
set dev.parent. This is required to have the parent device symlink show
up in sysfs, but not for proper operation of the mtd device itself.
Currently we have five drivers registering mtd devices during module
initialization, so they don't actually provide a parent device to link
to. That means we cannot WARN_ON() here, as it would trigger false
positives.

Make the comment a bit less firm in its assertion that dev.parent should
be set.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-10-13 09:21:12 -07:00
Johannes Thumshirn 35667b9983 mtd: Destroy mtd_idr on module_exit
Destroy mtd_idr on module_exit, reclaiming the allocated memory.

This was detected by the following semantic patch (written by Luis Rodriguez
<mcgrof@suse.com>)
<SmPL>
@ defines_module_init @
declarer name module_init, module_exit;
declarer name DEFINE_IDR;
identifier init;
@@

module_init(init);

@ defines_module_exit @
identifier exit;
@@

module_exit(exit);

@ declares_idr depends on defines_module_init && defines_module_exit @
identifier idr;
@@

DEFINE_IDR(idr);

@ on_exit_calls_destroy depends on declares_idr && defines_module_exit @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
  idr_destroy(&idr);
  ...
}

@ missing_module_idr_destroy depends on declares_idr && defines_module_exit && !on_exit_calls_destroy @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 +idr_destroy(&idr);
}
</SmPL>

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-09-28 17:36:57 -07:00
Brian Norris 57dd990c5e mtd: propagate error codes from add_mtd_device()
It makes more sense to return error statuses, not 1/0.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
2015-06-16 18:47:06 -07:00
Lars-Peter Clausen 57b8045d13 mtd: Switch to PM ops
Use dev_pm_ops instead of the legacy suspend/resume callbacks for the MTD
class suspend and resume operations.

While we are at it slightly reorder things to avoid the need for forward
declarations.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2015-05-07 00:18:22 -07:00
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
Artem Bityutskiy d5de20a9a1 mtd: kill dev_to_mtd helper
... 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>
2012-01-09 18:25:57 +00:00
Artem Bityutskiy ead995f8d4 mtd: introduce mtd_resume interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:46 +00:00
Artem Bityutskiy 3fe4bae884 mtd: introduce mtd_suspend interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:45 +00:00
Artem Bityutskiy b66005cd3e mtd: introduce mtd_unlock interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:40 +00:00