Commit Graph

172 Commits

Author SHA1 Message Date
Boris Brezillon 19e16fb4f3 mtd: Fix the check on nvmem_register() ret code
Commit 20167b70c8 ("nvmem: use EOPNOTSUPP instead of ENOSYS") changed
the nvmem_register() ret code from ENOSYS to EOPNOTSUPP when
CONFIG_NVMEM is not enabled, but the check in mtd_nvmem_add() was not
adjusted accordingly.

Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Alban Bedel <albeu@free.fr>
Fixes: c4dfa25ab3 ("mtd: add support for reading MTD devices via the nvmem API")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
2019-01-07 14:06:22 +01:00
Linus Torvalds 457fa3469a Char/Misc driver patches for 4.21-rc1
Here is the big set of char and misc driver patches for 4.21-rc1.
 
 Lots of different types of driver things in here, as this tree seems to
 be the "collection of various driver subsystems not big enough to have
 their own git tree" lately.
 
 Anyway, some highlights of the changes in here:
   - binderfs: is it a rule that all driver subsystems will eventually
     grow to have their own filesystem?  Binder now has one to handle the
     use of it in containerized systems.  This was discussed at the
     Plumbers conference a few months ago and knocked into mergable shape
     very fast by Christian Brauner.  Who also has signed up to be
     another binder maintainer, showing a distinct lack of good judgement :)
   - binder updates and fixes
   - mei driver updates
   - fpga driver updates and additions
   - thunderbolt driver updates
   - soundwire driver updates
   - extcon driver updates
   - nvmem driver updates
   - hyper-v driver updates
   - coresight driver updates
   - pvpanic driver additions and reworking for more device support
   - lp driver updates.  Yes really, it's _finally_ moved to the proper
     parallal port driver model, something I never thought I would see
     happen.  Good stuff.
   - other tiny driver updates and fixes.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of char and misc driver patches for 4.21-rc1.

  Lots of different types of driver things in here, as this tree seems
  to be the "collection of various driver subsystems not big enough to
  have their own git tree" lately.

  Anyway, some highlights of the changes in here:

   - binderfs: is it a rule that all driver subsystems will eventually
     grow to have their own filesystem? Binder now has one to handle the
     use of it in containerized systems.

     This was discussed at the Plumbers conference a few months ago and
     knocked into mergable shape very fast by Christian Brauner. Who
     also has signed up to be another binder maintainer, showing a
     distinct lack of good judgement :)

   - binder updates and fixes

   - mei driver updates

   - fpga driver updates and additions

   - thunderbolt driver updates

   - soundwire driver updates

   - extcon driver updates

   - nvmem driver updates

   - hyper-v driver updates

   - coresight driver updates

   - pvpanic driver additions and reworking for more device support

   - lp driver updates. Yes really, it's _finally_ moved to the proper
     parallal port driver model, something I never thought I would see
     happen. Good stuff.

   - other tiny driver updates and fixes.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-4.21-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (116 commits)
  MAINTAINERS: add another Android binder maintainer
  intel_th: msu: Fix an off-by-one in attribute store
  stm class: Add a reference to the SyS-T document
  stm class: Fix a module refcount leak in policy creation error path
  char: lp: use new parport device model
  char: lp: properly count the lp devices
  char: lp: use first unused lp number while registering
  char: lp: detach the device when parallel port is removed
  char: lp: introduce list to save port number
  bus: qcom: remove duplicated include from qcom-ebi2.c
  VMCI: Use memdup_user() rather than duplicating its implementation
  char/rtc: Use of_node_name_eq for node name comparisons
  misc: mic: fix a DMA pool free failure
  ptp: fix an IS_ERR() vs NULL check
  genwqe: Fix size check
  binder: implement binderfs
  binder: fix use-after-free due to ksys_close() during fdget()
  bus: fsl-mc: remove duplicated include files
  bus: fsl-mc: explicitly define the fsl_mc_command endianness
  misc: ti-st: make array read_ver_cmd static, shrinks object size
  ...
2018-12-28 20:54:57 -08:00
Alban Bedel c4dfa25ab3 mtd: add support for reading MTD devices via the nvmem API
Allow drivers that use the nvmem API to read data stored on MTD devices.
For this the mtd devices are registered as read-only NVMEM providers.

We don't support device tree systems for now.

Signed-off-by: Alban Bedel <albeu@free.fr>
[Bartosz:
  - include linux/nvmem-provider.h
  - set the name of the nvmem provider
  - set no_of_node to true in nvmem_config
  - don't check the return value of nvmem_unregister() - it cannot fail
  - tweaked the commit message]
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06 15:48:54 +01:00
Rafał Miłecki 1186af457c mtd: keep original flags for every struct mtd_info
When allocating a new partition mtd subsystem runs internal tests in the
allocate_partition(). They may result in modifying specified flags (e.g.
dropping some /features/ like write access).

Those constraints don't have to be necessary true for subpartitions. It
may happen parent partition isn't block aligned (effectively disabling
write access) while subpartition may fit blocks nicely. In such case all
checks should be run again (starting with original flags value).

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-02 09:29:16 +01:00
Miquel Raynal 89f706dbd5 mtd: fix Coverity integer handling issue
A Coverity robot reported an integer handling issue
(OVERFLOW_BEFORE_WIDEN) in the potentially overflowing expression:

    (mtd_div_by_ws(mtd->size, mtd) - mtd_div_by_ws(offs, mtd)) *
    mtd_oobavail(mtd, ops)

While such overflow will certainly never happen due to the numbers
handled, it is cleaner to fix this operation anyway.

The problem is that all the maths include 32-bit quantities, while the
result is stored in an explicit 64-bit value.

As maxooblen will just be compared with a size_t, let's change the
type of the variable to a size_t. This will not fix anything but will
clarify a bit the situation. Then, do an explicit cast to fix Coverity
warning.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-12-02 09:20:41 +01:00
Miquel Raynal 89fd23efa0 mtd: Fallback to ->_read/write() when ->_read/write_oob() is missing
Some MTD sublayers/drivers are implementing ->_read/write() and
not ->_read/write_oob().

While for NAND devices both are usually valid, for NOR devices, using
the _oob variant has no real meaning. But, as the MTD layer is supposed
to hide as much as possible the flash complexity to the user, there is
no reason to error out while it is just a matter of rewritting things
internally.

Add a fallback on mtd->_read() (resp. mtd->_write()) when the user calls
mtd_read_oob() (resp. mtd_write_oob()) while mtd->_read_oob() (resp.
mtd->_write_oob) is not implemented. There is already a fallback on the
_oob variant if the former is used.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-07-18 16:44:03 +02:00
Linus Torvalds f4e70c2e5f MTD changes:
Core changes:
   - Add a sysfs attribute to expose available OOB size
 
   Driver changes:
   - Remove HAS_DMA dependency on various drivers
   - Use dev_get_drvdata() instead of platform_get_drvdata() in docg3
   - Replace msleep by usleep_range() in the dataflash driver
   - Avoid VLA usage in nftl layers
   - Remove useless .owner assignment in pismo
   - Fix various issues in the CFI driver
   - Improve TRX partition handling expose a DT compat for this part
     parser
   - Clarify OFFSET_CONTINUOUS meaning
 
 NAND changes:
   Core changes:
   - Add Miquel as a NAND maintainer
   - Add access mode to the nand_page_io_req struct
   - Fix kernel-doc in rawnand.h
   - Support bit-wise majority to recover from corrupted ONFI parameter
     pages
   - Stop checking FAIL bit after a SET_FEATURES, as documented in the
     ONFI spec
 
   Raw NAND Driver changes:
   - Fix and cleanup the error path of many NAND controller drivers
   - GPMI:
     * Cleanup/simplification of a few aspects in the driver
     * Take ECC setup specified in the DT into account
   - sunxi: remove support for GPIO-based R/B polling
   - MTK:
     * Use of_device_get_match_data() instead of of_match_device()
     * Add an entry in MAINTAINERS for this driver
     * Fix nand-ecc-step-size and nand-ecc-strength description in the DT
       bindings doc
   - fsl_ifc: fix ->cmdfunc() to read more than one ONFI parameter page
 
   OneNAND driver changes:
   - samsung: use dev_get_drvdata() instead of platform_get_drvdata()
 
 SPI NOR changes:
   Core changes:
   - Add support for a bunch of SPI NOR chips
   - Clear EAR reg when switching to 3-byte addressing mode on Winbond
     chips
 
   SPI NOR controller driver changes:
   - cadence: Add DMA support for direct mode reads
   - hisi: Prefix a few functions with hisi_
   - intel:
     * Mark the driver as "dangerous" in Kconfig
     * Fix atomic sequence handling
     * Pass a 40us delay (instead of 0us) to readl_poll_timeout()
   - fsl:
     * fix a typo in a function name
     * add support for IP variants embedded in the ls2080a and ls1080a
       SoCs
   - stm32: request exclusive control of the reset line
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Merge tag 'mtd/for-4.18' of git://git.infradead.org/linux-mtd

Pull MTD updates from Boris Brezillon:
 "Core changes:
   - Add a sysfs attribute to expose available OOB size

  Driver changes:
   - Remove HAS_DMA dependency on various drivers
   - Use dev_get_drvdata() instead of platform_get_drvdata() in docg3
   - Replace msleep by usleep_range() in the dataflash driver
   - Avoid VLA usage in nftl layers
   - Remove useless .owner assignment in pismo
   - Fix various issues in the CFI driver
   - Improve TRX partition handling expose a DT compat for this part
     parser
   - Clarify OFFSET_CONTINUOUS meaning

  NAND core changes:
   - Add Miquel as a NAND maintainer
   - Add access mode to the nand_page_io_req struct
   - Fix kernel-doc in rawnand.h
   - Support bit-wise majority to recover from corrupted ONFI parameter
     pages
   - Stop checking FAIL bit after a SET_FEATURES, as documented in the
     ONFI spec

  Raw NAND Driver changes:
   - Fix and cleanup the error path of many NAND controller drivers
   - GPMI:
      + Cleanup/simplification of a few aspects in the driver
      + Take ECC setup specified in the DT into account
   - sunxi: remove support for GPIO-based R/B polling
   - MTK:
      + Use of_device_get_match_data() instead of of_match_device()
      + Add an entry in MAINTAINERS for this driver
      + Fix nand-ecc-step-size and nand-ecc-strength description in the
        DT bindings doc
   - fsl_ifc: fix ->cmdfunc() to read more than one ONFI parameter page

  OneNAND driver changes:
   - samsung: use dev_get_drvdata() instead of platform_get_drvdata()

  SPI NOR core changes:
   - Add support for a bunch of SPI NOR chips
   - Clear EAR reg when switching to 3-byte addressing mode on Winbond
     chips

  SPI NOR controller driver changes:
   - cadence: Add DMA support for direct mode reads
   - hisi: Prefix a few functions with hisi_
   - intel:
      + Mark the driver as "dangerous" in Kconfig
      + Fix atomic sequence handling
      + Pass a 40us delay (instead of 0us) to readl_poll_timeout()
   - fsl:
      + fix a typo in a function name
      + add support for IP variants embedded in the ls2080a and ls1080a
        SoCs
   - stm32: request exclusive control of the reset line"

* tag 'mtd/for-4.18' of git://git.infradead.org/linux-mtd: (66 commits)
  mtd: nand: Pass mode information to nand_page_io_req
  mtd: cfi_cmdset_0002: Change erase one block to enable XIP once
  mtd: cfi_cmdset_0002: Change erase functions to check chip good only
  mtd: cfi_cmdset_0002: Change erase functions to retry for error
  mtd: cfi_cmdset_0002: Change definition naming to retry write operation
  mtd: cfi_cmdset_0002: Change write buffer to check correct value
  mtd: cmdlinepart: Update comment for introduction of OFFSET_CONTINUOUS
  mtd: bcm47xxpart: add of_match_table with a new DT binding
  dt-bindings: mtd: document Broadcom's BCM47xx partitions
  mtd: spi-nor: Add support for EN25QH32
  mtd: spi-nor: Add support for is25wp series chips
  mtd: spi-nor: Add Winbond w25q32jv support
  mtd: spi-nor: fsl-quadspi: add support for ls2080a/ls1080a
  mtd: spi-nor: stm32-quadspi: explicitly request exclusive reset control
  mtd: spi-nor: intel: provide a range for poll_timout
  mtd: spi-nor: fsl-quadspi: fix api naming typo _init_ahb_read
  mtd: spi-nor: intel-spi: Explicitly mark the driver as dangerous in Kconfig
  mtd: spi-nor: intel-spi: Fix atomic sequence handling
  mtd: rawnand: Do not check FAIL bit when executing a SET_FEATURES op
  mtd: rawnand: use bit-wise majority to recover the ONFI param page
  ...
2018-06-08 10:39:20 -07:00
Christoph Hellwig 3f3942aca6 proc: introduce proc_create_single{,_data}
Variants of proc_create{,_data} that directly take a seq_file show
callback and drastically reduces the boilerplate code in the callers.

All trivial callers converted over.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:23:35 +02:00
Rafał Miłecki 5ac67ce36c mtd: move code adding (registering) partitions to the parse_mtd_partitions()
This commit slightly simplifies the code. Every parse_mtd_partitions()
caller (out of two existing ones) had to add partitions & cleanup parser
on its own. This moves that responsibility into the function.

That change also allows dropping struct mtd_partitions argument.

There is one minor behavior change caused by this cleanup. If
parse_mtd_partitions() fails to add partitions (add_mtd_partitions()
return an error) then mtd_device_parse_register() will still try to
add (register) fallback partitions. It's a real corner case affecting
one of uncommon error paths and shouldn't cause any harm.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-05-07 10:10:47 +02:00
Xiaolei Li 7cc9aa669a mtd: Add sysfs attribute for mtd OOB available size
Expose mtd OOB available size by sysfs file. Then users can get available
OOB size by accessing /sys/class/mtd/mtdX/oobavail.

Signed-off-by: Xiaolei Li <xiaolei.li@mediatek.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-04-22 20:07:06 +02:00
Xiaolei Li c77a931206 mtd: Fix some function description mismatches in mtdcore.c
In mtdcore.c, some function descriptions do not match function
definitions. Just fix these mismatches.

Signed-off-by: Xiaolei Li <xiaolei.li@mediatek.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-03-29 09:31:54 +02:00
Rafał Miłecki 55a999a041 mtd: update documentation of mtd_device_parse_register()
In the commit 2c77c57d22 ("mtd: move code adding master MTD out of
mtd_add_device_partitions()") behavior of mtd_device_parse_register()
has very slightly changed. It's a pretty non-significant order change
to match updated function behavior.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-03-29 09:29:36 +02:00
Boris Brezillon e7bfb3fdbd mtd: Stop updating erase_info->state and calling mtd_erase_callback()
MTD users are no longer checking erase_info->state to determine if the
erase operation failed or succeeded. Moreover, mtd_erase_callback() is
now a NOP.

We can safely get rid of all mtd_erase_callback() calls and all
erase_info->state assignments. While at it, get rid of the
erase_info->state field, all MTD_ERASE_XXX definitions and the
mtd_erase_callback() function.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Bert Kenward <bkenward@solarflare.com>
---
Changes in v2:
- Address a few coding style issues (reported by Miquel)
- Remove comments that are no longer valid (reported by Miquel)
2018-03-21 09:50:56 +01:00
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