Pull UBI update from Richard Weinberger:
 "This contains a single change for UBI:

   - Select fastmap anchor PEBs considering wear level rules"

* tag 'for-linus-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubi: Select fastmap anchor PEBs considering wear level rules

Pull MTD updates from Richard Weinberger:
 "MTD core changes:
   - partition parser: Support MTD names containing one or more colons.
   - mtdblock: clear cache_state to avoid writing to bad blocks
     repeatedly.

  Raw NAND core changes:
   - Stop using nand_release(), patched all drivers.
   - Give more information about the ECC weakness when not matching the
     chip's requirement.
   - MAINTAINERS updates.
   - Support emulated SLC mode on MLC NANDs.
   - Support "constrained" controllers, adapt the core and ONFI/JEDEC
     table parsing and Micron's code.
   - Take check_only into account.
   - Add an invalid ECC mode to discriminate with valid ones.
   - Return an enum from of_get_nand_ecc_algo().
   - Drop OOB_FIRST placement scheme.
   - Introduce nand_extract_bits().
   - Ensure a consistent bitflips numbering.
   - BCH lib:
      - Allow easy bit swapping.
      - Rework a little bit the exported function names.
   - Fix nand_gpio_waitrdy().
   - Propage CS selection to sub operations.
   - Add a NAND_NO_BBM_QUIRK flag.
   - Give the possibility to verify a read operation is supported.
   - Add a helper to check supported operations.
   - Avoid indirect access to ->data_buf().
   - Rename the use_bufpoi variables.
   - Fix comments about the use of bufpoi.
   - Rename a NAND chip option.
   - Reorder the nand_chip->options flags.
   - Translate obscure bitfields into readable macros.
   - Timings:
      - Fix default values.
      - Add mode information to the timings structure.

  Raw NAND controller driver changes:
   - Fixed many error paths.
   - Arasan
      - New driver
   - Au1550nd:
      - Various cleanups
      - Migration to ->exec_op()
   - brcmnand:
      - Misc cleanup.
      - Support v2.1-v2.2 controllers.
      - Remove unused including <linux/version.h>.
      - Correctly verify erased pages.
      - Fix Hamming OOB layout.
   - Cadence
      - Make cadence_nand_attach_chip static.
   - Cafe:
      - Set the NAND_NO_BBM_QUIRK flag
   - cmx270:
      - Remove this controller driver.
   - cs553x:
      - Misc cleanup
      - Migration to ->exec_op()
   - Davinci:
      - Misc cleanup.
      - Migration to ->exec_op()
   - Denali:
      - Add more delays before latching incoming data
   - Diskonchip:
      - Misc cleanup
      - Migration to ->exec_op()
   - Fsmc:
      - Change to non-atomic bit operations.
   - GPMI:
      - Use nand_extract_bits()
      - Fix runtime PM imbalance.
   - Ingenic:
      - Migration to exec_op()
      - Fix the RB gpio active-high property on qi, lb60
      - Make qi_lb60_ooblayout_ops static.
   - Marvell:
      - Misc cleanup and small fixes
   - Nandsim:
      - Fix the error paths, driver wide.
   - Omap_elm:
      - Fix runtime PM imbalance.
   - STM32_FMC2:
      - Misc cleanups (error cases, comments, timeout valus, cosmetic
        changes).

  SPI NOR core changes:
   - Add, update support and fix few flashes.
   - Prepare BFPT parsing for JESD216 rev D.
   - Kernel doc fixes.

  CFI changes:
   - Support the absence of protection registers for Intel CFI flashes.
   - Replace zero-length array with flexible-arrays"

* tag 'mtd/for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux: (208 commits)
  mtd: clear cache_state to avoid writing to bad blocks repeatedly
  mtd: parser: cmdline: Support MTD names containing one or more colons
  mtd: physmap_of_gemini: remove defined but not used symbol 'syscon_match'
  mtd: rawnand: Add an invalid ECC mode to discriminate with valid ones
  mtd: rawnand: Return an enum from of_get_nand_ecc_algo()
  mtd: rawnand: Drop OOB_FIRST placement scheme
  mtd: rawnand: Avoid a typedef
  mtd: Fix typo in mtd_ooblayout_set_databytes() description
  mtd: rawnand: Stop using nand_release()
  mtd: rawnand: nandsim: Reorganize ns_cleanup_module()
  mtd: rawnand: nandsim: Rename a label in ns_init_module()
  mtd: rawnand: nandsim: Manage lists on error in ns_init_module()
  mtd: rawnand: nandsim: Fix the label pointing on nand_cleanup()
  mtd: rawnand: nandsim: Free erase_block_wear on error
  mtd: rawnand: nandsim: Use an additional label when freeing the nandsim object
  mtd: rawnand: nandsim: Stop using nand_release()
  mtd: rawnand: nandsim: Free the partition names in ns_free()
  mtd: rawnand: nandsim: Free the allocated device on error in ns_init()
  mtd: rawnand: nandsim: Free partition names on error in ns_init()
  mtd: rawnand: nandsim: Fix the two ns_alloc_device() error paths
  ...

The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.

Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There is a risk that the fastmap anchor PEB is alternating between
just two PEBs, the current anchor and the previous anchor that was just
deleted. As the fastmap pools gets the first take on free PEBs, the
pools may leave no free PEBs to be selected as the new anchor,
resulting in the two PEBs alternating behaviour. If the anchor PEBs gets
a high erase count the PEBs will not be used by the pools but remain in
ubi->free, even more increasing the likelihood they will be used as
anchors.

Getting stuck using only a couple of PEBs continuously will result in an
uneven wear, eventually leading to failure.

To fix this:

- Choose the fastmap anchor when the most free PEBs are available. This is
  during rebuilding of the fastmap pools, after the unused pool PEBs are
  added to ubi->free but before the pools are populated again from the
  free PEBs. Also reserve an additional second best PEB as a candidate
  for the next time the fast map anchor is updated. If a better PEB is
  found the next time the fast map anchor is updated, the candidate is
  made available for building the pools.

- Enable anchor move within the anchor area again as it is useful for
  distributing wear.

- The anchor candidate for the next fastmap update is the most suited free
  PEB. Check this PEB's erase count during wear leveling. If the wear
  leveling limit is exceeded, the PEB is considered unsuitable for now. As
  all other non used anchor area PEBs should be even worse, free up the
  used anchor area PEB with the lowest erase count.

Signed-off-by: Arne Edholm <arne.edholm@axis.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

The pgprot argument to __vmalloc is always PAGE_KERNEL now, so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com> [hyperv]
Acked-by: Gao Xiang <xiang@kernel.org> [erofs]
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Wei Liu <wei.liu@kernel.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-22-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Raw NAND core changes:
* Stop using nand_release(), patched all drivers.
* Give more information about the ECC weakness when not matching the
  chip's requirement.
* MAINTAINERS updates.
* Support emulated SLC mode on MLC NANDs.
* Support "constrained" controllers, adapt the core and ONFI/JEDEC
  table parsing and Micron's code.
* Take check_only into account.
* Add an invalid ECC mode to discriminate with valid ones.
* Return an enum from of_get_nand_ecc_algo().
* Drop OOB_FIRST placement scheme.
* Introduce nand_extract_bits().
* Ensure a consistent bitflips numbering.
* BCH lib:
  - Allow easy bit swapping.
  - Rework a little bit the exported function names.
* Fix nand_gpio_waitrdy().
* Propage CS selection to sub operations.
* Add a NAND_NO_BBM_QUIRK flag.
* Give the possibility to verify a read operation is supported.
* Add a helper to check supported operations.
* Avoid indirect access to ->data_buf().
* Rename the use_bufpoi variables.
* Fix comments about the use of bufpoi.
* Rename a NAND chip option.
* Reorder the nand_chip->options flags.
* Translate obscure bitfields into readable macros.
* Timings:
  - Fix default values.
  - Add mode information to the timings structure.

Raw NAND controller driver changes:
* Fixed many error paths.
* Arasan
  - New driver
* Au1550nd:
  - Various cleanups
  - Migration to ->exec_op()
* brcmnand:
  - Misc cleanup.
  - Support v2.1-v2.2 controllers.
  - Remove unused including <linux/version.h>.
  - Correctly verify erased pages.
  - Fix Hamming OOB layout.
* Cadence
  - Make cadence_nand_attach_chip static.
* Cafe:
  - Set the NAND_NO_BBM_QUIRK flag
* cmx270:
  - Remove this controller driver.
* cs553x:
  - Misc cleanup
  - Migration to ->exec_op()
* Davinci:
  - Misc cleanup.
  - Migration to ->exec_op()
* Denali:
  - Add more delays before latching incoming data
* Diskonchip:
   - Misc cleanup
   - Migration to ->exec_op()
* Fsmc:
  - Change to non-atomic bit operations.
* GPMI:
  - Use nand_extract_bits()
  - Fix runtime PM imbalance.
* Ingenic:
  - Migration to exec_op()
  - Fix the RB gpio active-high property on qi, lb60
  - Make qi_lb60_ooblayout_ops static.
* Marvell:
   - Misc cleanup and small fixes
* Nandsim:
  - Fix the error paths, driver wide.
* Omap_elm:
  - Fix runtime PM imbalance.
* STM32_FMC2:
  - Misc cleanups (error cases, comments, timeout valus, cosmetic
    changes).

3bfa7e141b0b ("fs/seq_file.c: seq_read(): add info message about buggy .next functions")
showed that we don't use seq_file correctly.
So make sure that our ->next function always updates the position.

Fixes: 7bccd12d27b7 ("ubi: Add debugfs file for tracking PEB state")
Signed-off-by: Richard Weinberger <richard@nod.at>

The MTD layer provides an SLC mode (purely software emulation of SLC
behavior) addressing the paired-pages corruption issue, which was the
main reason for refusing attaching MLC NANDs to UBI.

Relax this rule and allow partitions that have the
MTD_EMULATE_SLC_ON_MLC flag set to be attached.

Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Richard Weinberger <richard@nod.at>
Link: https://lore.kernel.org/linux-mtd/20200503155341.16712-9-miquel.raynal@bootlin.com

Pull UBI and UBIFS updates from Richard Weinberger:

 - Fix for memory leaks around UBIFS orphan handling

 - Fix for memory leaks around UBI fastmap

 - Remove zero-length array from ubi-media.h

 - Fix for TNC lookup in UBIFS orphan code

* tag 'for-linus-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubi: ubi-media.h: Replace zero-length array with flexible-array member
  ubifs: Fix out-of-bounds memory access caused by abnormal value of node_len
  ubi: fastmap: Only produce the initial anchor PEB when fastmap is used
  ubi: fastmap: Free unused fastmap anchor peb during detach
  ubifs: ubifs_add_orphan: Fix a memory leak bug
  ubifs: ubifs_jnl_write_inode: Fix a memory leak bug
  ubifs: Fix ubifs_tnc_lookup() usage in do_kill_orphans()

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Richard Weinberger <richard@nod.at>