Pull UBI/UBIFS/JFFS2 updates from Richard Weinberger:
 "This pull request contains mostly fixes for UBI, UBIFS and JFFS2:

  UBI:

   - Fix a regression around producing a anchor PEB for fastmap.

     Due to a change in our locking fastmap was unable to produce fresh
     anchors an re-used the existing one a way to often.

  UBIFS:

   - Fixes for endianness. A few places blindly assumed little endian.

   - Fix for a memory leak in the orphan code.

   - Fix for a possible crash during a commit.

   - Revert a wrong bugfix.

  JFFS2:

   - Revert a bad bugfix (false positive from a code checking tool)"

* tag 'upstream-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  Revert "jffs2: Fix possible null-pointer dereferences in jffs2_add_frag_to_fragtree()"
  ubi: Fix producing anchor PEBs
  ubifs: ubifs_tnc_start_commit: Fix OOB in layout_in_gaps
  ubifs: do_kill_orphans: Fix a memory leak bug
  Revert "ubifs: Fix memory leak bug in alloc_ubifs_info() error path"
  ubifs: Fix type of sup->hash_algo
  ubifs: Fixed missed le64_to_cpu() in journal
  ubifs: Force prandom result to __le32
  ubifs: Remove obsolete TODO from dfs_file_write()
  ubi: Fix warning static is not at beginning of declaration
  ubi: Print skip_check in ubi_dump_vol_info()

Pull removal of most of fs/compat_ioctl.c from Arnd Bergmann:
 "As part of the cleanup of some remaining y2038 issues, I came to
  fs/compat_ioctl.c, which still has a couple of commands that need
  support for time64_t.

  In completely unrelated work, I spent time on cleaning up parts of
  this file in the past, moving things out into drivers instead.

  After Al Viro reviewed an earlier version of this series and did a lot
  more of that cleanup, I decided to try to completely eliminate the
  rest of it and move it all into drivers.

  This series incorporates some of Al's work and many patches of my own,
  but in the end stops short of actually removing the last part, which
  is the scsi ioctl handlers. I have patches for those as well, but they
  need more testing or possibly a rewrite"

* tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (42 commits)
  scsi: sd: enable compat ioctls for sed-opal
  pktcdvd: add compat_ioctl handler
  compat_ioctl: move SG_GET_REQUEST_TABLE handling
  compat_ioctl: ppp: move simple commands into ppp_generic.c
  compat_ioctl: handle PPPIOCGIDLE for 64-bit time_t
  compat_ioctl: move PPPIOCSCOMPRESS to ppp_generic
  compat_ioctl: unify copy-in of ppp filters
  tty: handle compat PPP ioctls
  compat_ioctl: move SIOCOUTQ out of compat_ioctl.c
  compat_ioctl: handle SIOCOUTQNSD
  af_unix: add compat_ioctl support
  compat_ioctl: reimplement SG_IO handling
  compat_ioctl: move WDIOC handling into wdt drivers
  fs: compat_ioctl: move FITRIM emulation into file systems
  gfs2: add compat_ioctl support
  compat_ioctl: remove unused convert_in_user macro
  compat_ioctl: remove last RAID handling code
  compat_ioctl: remove /dev/raw ioctl translation
  compat_ioctl: remove PCI ioctl translation
  compat_ioctl: remove joystick ioctl translation
  ...

When a new fastmap is about to be written UBI must make sure it has a
free block for a fastmap anchor available. For this ubi_update_fastmap()
calls ubi_ensure_anchor_pebs(). This stopped working with 2e8f08deabbc
("ubi: Fix races around ubi_refill_pools()"), with this commit the wear
leveling code is blocked and can no longer produce free PEBs. UBI then
more often than not falls back to write the new fastmap anchor to the
same block it was already on which means the same erase block gets
erased during each fastmap write and wears out quite fast.

As the locking prevents us from producing the anchor PEB when we
actually need it, this patch changes the strategy for creating the
anchor PEB. We no longer create it on demand right before we want to
write a fastmap, but instead we create an anchor PEB right after we have
written a fastmap. This gives us enough time to produce a new anchor PEB
before it is needed. To make sure we have an anchor PEB for the very
first fastmap write we call ubi_ensure_anchor_pebs() during
initialisation as well.

Fixes: 2e8f08deabbc ("ubi: Fix races around ubi_refill_pools()")
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

Compiler generates following warning when kernel is built with W=1:

drivers/mtd/ubi/ubi.h:971:1: warning: ‘static’ is not at beginning
of declaration [-Wold-style-declaration]

This commit fixes this by correctly ordering keywords.

Signed-off-by: Rishi Gupta <gupt21@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

It might be interesting, if "skip_check" is set or not, so lets print
this flag in ubi_dump_vol_info() as well.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Richard Weinberger <richard@nod.at>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Heiko Schocher <hs@denx.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: linux-mtd@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Each of these drivers has a copy of the same trivial helper function to
convert the pointer argument and then call the native ioctl handler.

We now have a generic implementation of that, so use it.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

If volume size is not a multiple of 512, ubi block cuts
off the last bytes of an volume since the block layer works
on 512 byte sectors.
This can happen especially on NOR flash with minimal io
size of 1.

To avoid unpleasant surprises, print a warning.

Signed-off-by: Richard Weinberger <richard@nod.at>

Running stress test io_paral (A pressure ubi test in mtd-utils) on an
UBI device with fewer PEBs (fastmap enabled) may cause ENOSPC errors and
make UBI device read-only, but there are still free PEBs on the UBI
device. This problem can be easily reproduced by performing the following
steps on a 2-core machine:
  $ modprobe nandsim first_id_byte=0x20 second_id_byte=0x33 parts=80
  $ modprobe ubi mtd="0,0" fm_autoconvert
  $ ./io_paral /dev/ubi0

We may see the following verbose:
(output)
  [io_paral] update_volume():108: failed to write 380 bytes at offset
  95920 of volume 2
  [io_paral] update_volume():109: update: 97088 bytes
  [io_paral] write_thread():227: function pwrite() failed with error 28
  (No space left on device)
  [io_paral] write_thread():229: cannot write 15872 bytes to offs 31744,
  wrote -1
(dmesg)
  ubi0 error: ubi_wl_get_peb [ubi]: Unable to get a free PEB from user WL
  pool
  ubi0 warning: ubi_eba_write_leb [ubi]: switch to read-only mode
  CPU: 0 PID: 2027 Comm: io_paral Not tainted 5.3.0-rc2-00001-g5986cd0 #9
  ubi0 warning: try_write_vid_and_data [ubi]: failed to write VID header
  to LEB 2:5, PEB 18
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0
  -0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  Call Trace:
    dump_stack+0x85/0xba
    ubi_eba_write_leb+0xa1e/0xa40 [ubi]
    vol_cdev_write+0x307/0x520 [ubi]
    vfs_write+0xfa/0x280
    ksys_pwrite64+0xc5/0xe0
    __x64_sys_pwrite64+0x22/0x30
    do_syscall_64+0xbf/0x440

In function ubi_wl_get_peb, the operation of filling the pool
(ubi_update_fastmap) with free PEBs and fetching a free PEB from the pool
is not atomic. After thread A filling the pool with free PEB, free PEB may
be taken away by thread B. When thread A checks the expression again, the
condition is still unsatisfactory. At this time, there may still be free
PEBs on UBI that can be filled into the pool.

This patch increases the number of attempts to obtain PEB. An extreme
case (No free PEBs left after creating test volumes) has been tested on
different type of machines for 100 times. The biggest number of attempts
are shown below:

             x86_64     arm64
  2-core        4         4
  4-core        8         4
  8-core        4         4

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

To make sure that Fastmap can use a PEB within the first 64
PEBs, UBI moves blocks away from that area.
It uses regular wear-leveling for that job.

An anchor move can be triggered if no PEB is free in this area
or because of anticipation. In the latter case it can happen
that UBI decides to move a block but finds a free PEB
within the same area.
This case is in vain an increases only erase counters.

Catch this case and cancel wear-leveling if this happens.

Signed-off-by: Richard Weinberger <richard@nod.at>