Most OMAP FB LCD drivers don't have anything to do in their panel
callbacks. This leads to a large set of empty boilerplate functions in the
panel drivers. Make those callbacks optional by checking if they are set
before calling them. This allows those boilerplate functions to be removed.

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

None of the lcd_panel structs defined by the OMAP LCD drivers are
referenced outside of their compilation unit. Follow best practices and
mark them as static.

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Every single one of the OMAP fbdev LCD drivers implements no-op remove,
suspend and resume callbacks for their platform_driver. This is not
necessary as the driver core handles the case where the callbacks are not
set just fine. So they are just unnecessary boilerplate that can be
removed.

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Drop open_file_generic(), use simple_open() instead of it.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Add missing error check for ioremap_nocache() failure
(prevents NULL pointer dereference on error).

Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
[b.zolnierkie: minor fixes]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Fix:

WARNING: drivers/video/fbdev/pmagb-b-fb.o(.text+0x6dc): Section mismatch in reference from the function pmagbbfb_probe() to the function .init.text:pmagbbfb_erase_cursor()
The function pmagbbfb_probe() 
references the function __init pmagbbfb_erase_cursor().
This is often because pmagbbfb_probe lacks a __init
annotation or the annotation of pmagbbfb_erase_cursor is wrong.

-- a fallout from a missed update from commit 5b1638d9 ("VIDEO: 
PMAGB-B: Fix section mismatch") and then commit 48c68c4f ("Drivers: 
video: remove __dev* attributes.")
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Fix:

WARNING: drivers/video/fbdev/pmag-ba-fb.o(.text+0x308): Section mismatch in reference from the function pmagbafb_probe() to the function .init.text:pmagbafb_erase_cursor()
The function pmagbafb_probe()
references the function __init pmagbafb_erase_cursor().
This is often because pmagbafb_probe lacks a __init
annotation or the annotation of pmagbafb_erase_cursor is wrong.

-- a fallout from a missed update from commit 9625b513 ("VIDEO: 
PMAG-BA: Fix section mismatch") and then commit 48c68c4f ("Drivers: 
video: remove __dev* attributes.")
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Having obtained panel device node in clcdfb_of_init_display() it allows to
generalize and simplify two more helper functions clcdfb_of_get_backlight()
and clcdfb_of_get_mode().

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

There is no necessity to pass an endpoint device node to custom panel
initialization functions, because a child panel device node should be
sufficient, note that the existing init_panel() callback declaration from
linux/amba/clcd.h already prompts to use the panel device node here.

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

To simplify the task of looking through the list of included headers sort
them out alphabetically, some of the truly redundant headers are removed
from the list.

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Use DEVICE_ATTR_RW for read-write attributes.  This simplifies the
source code, improves readbility, and reduces the chance of
inconsistencies.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@rw@
declarer name DEVICE_ATTR;
identifier x,x_show,x_store;
@@

DEVICE_ATTR(x, \(0644\|S_IRUGO|S_IWUSR\), x_show, x_store);

@script:ocaml@
x << rw.x;
x_show << rw.x_show;
x_store << rw.x_store;
@@

if not (x^"_show" = x_show && x^"_store" = x_store)
then Coccilib.include_match false

@@
declarer name DEVICE_ATTR_RW;
identifier rw.x,rw.x_show,rw.x_store;
@@

- DEVICE_ATTR(x, \(0644\|S_IRUGO|S_IWUSR\), x_show, x_store);
+ DEVICE_ATTR_RW(x);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Currently when a simplefb needs both clocks and regulators and one
of the regulators returns -EPROBE_DEFER when we try to get it, we end
up disabling the clocks. This causes the screen to go blank; and in some
cases my cause hardware state to be lost resulting in the framebuffer not
working at all.

This commit splits the get and enable steps and only enables
clocks and regulators after successfully getting all of them,
fixing the disabling of the clocks which were left enabled by
the firmware setting up the simplefb.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

fbcon can deal with vc_hi_font_mask (the upper 256 chars) and adjust
the vc attrs dynamically when vc_hi_font_mask is changed at
fbcon_init().  When the vc_hi_font_mask is set, it remaps the attrs in
the existing console buffer with one bit shift up (for 9 bits), while
it remaps with one bit shift down (for 8 bits) when the value is
cleared.  It works fine as long as the font gets updated after fbcon
was initialized.

However, we hit a bizarre problem when the console is switched to
another fb driver (typically from vesafb or efifb to drmfb).  At
switching to the new fb driver, we temporarily rebind the console to
the dummy console, then rebind to the new driver.  During the
switching, we leave the modified attrs as is.  Thus, the new fbcon
takes over the old buffer as if it were to contain 8 bits chars
(although the attrs are still shifted for 9 bits), and effectively
this results in the yellow color texts instead of the original white
color, as found in the bugzilla entry below.

An easy fix for this is to re-adjust the attrs before leaving the
fbcon at con_deinit callback.  Since the code to adjust the attrs is
already present in the current fbcon code, in this patch, we simply
factor out the relevant code, and call it from fbcon_deinit().

Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1000619Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

The current code calculates the number of color map entries as
1 << info->var.bits_per_pixel. For 32bpp modes, 1 << 32 is 0 when
written to an int variable. As a consequence, the subsequent copying
of the default (non-empty) color map into our newly allocated color map
fails and imxfb's probe function returns an error.

On both imx1 and imx21 platforms, the color map is used only for modes
with <= 8bpp. By allocating 256 entries for the color map, we're on the
safe side.
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

The object maxinefb_fix of type fb_fix_screeninfo is never referenced
after initialization by maxinefb_init. In the init function, the object
and one of its fields is only stored into another variable. So, the
object and its fields are never referenced anywhere after initialization
and therefore add __initdata to its declaration.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Prepare to mark sensitive kernel structures for randomization by making
sure they're using designated initializers. These were identified during
allyesconfig builds of x86, arm, and arm64, with most initializer fixes
extracted from grsecurity.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Prepare to mark sensitive kernel structures for randomization by making
sure they're using designated initializers. These were identified during
allyesconfig builds of x86, arm, and arm64, with most initializer fixes
extracted from grsecurity.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

The current definitions of DMACR_HM() and DMACR_TM() are correct only
for imx1, they're wrong for imx21.

The macros are meant for legacy board files only, they're not applicable
for boards using device tree.

At the moment, there are no boards using these macros. So it should be
safe to drop them rather than making them work for both imx1 and imx21,
which would require a change in the platform data struct.
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

fbdev fixes for v4.10-rc2:

- bring fbdev subsystem back into Maintained mode
- add missing devm_ioremap() error checking to cobalt_lcdfb driver

Here, If devm_ioremap will fail. It will return NULL.
Kernel can run into a NULL-pointer dereference.
This error check will avoid NULL pointer dereference.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Acked-by: Yoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

I would like to help with fbdev maintenance.  I can dedicate some time
for reviewing and handling patches but won't have time for much more.

The subsystem will remain in maintenance mode (no new drivers will be
added to it).

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

Pull DAX updates from Dan Williams:
 "The completion of Jan's DAX work for 4.10.

  As I mentioned in the libnvdimm-for-4.10 pull request, these are some
  final fixes for the DAX dirty-cacheline-tracking invalidation work
  that was merged through the -mm, ext4, and xfs trees in -rc1. These
  patches were prepared prior to the merge window, but we waited for
  4.10-rc1 to have a stable merge base after all the prerequisites were
  merged.

  Quoting Jan on the overall changes in these patches:

     "So I'd like all these 6 patches to go for rc2. The first three
      patches fix invalidation of exceptional DAX entries (a bug which
      is there for a long time) - without these patches data loss can
      occur on power failure even though user called fsync(2). The other
      three patches change locking of DAX faults so that ->iomap_begin()
      is called in a more relaxed locking context and we are safe to
      start a transaction there for ext4"

  These have received a build success notification from the kbuild
  robot, and pass the latest libnvdimm unit tests. There have not been
  any -next releases since -rc1, so they have not appeared there"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  ext4: Simplify DAX fault path
  dax: Call ->iomap_begin without entry lock during dax fault
  dax: Finish fault completely when loading holes
  dax: Avoid page invalidation races and unnecessary radix tree traversals
  mm: Invalidate DAX radix tree entries only if appropriate
  ext2: Return BH_New buffers for zeroed blocks

Pull documentation fixes from Jonathan Corbet:
 "Two small fixes:

   - A merge error on my part broke the DocBook build. I've
     requisitioned one of tglx's frozen sharks for appropriate
     disciplinary action and resolved to be more careful about testing
     the DocBook stuff as long as it's still around.

   - Fix an error in unaligned-memory-access.txt"

* tag 'docs-4.10-rc1-fix' of git://git.lwn.net/linux:
  Documentation/unaligned-memory-access.txt: fix incorrect comparison operator
  docs: Fix build failure

Pull crypto fix from Herbert Xu:
 "This fixes a boot failure on some platforms when crypto self test is
  enabled along with the new acomp interface"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: testmgr - Use heap buffer for acomp test input

 mm/filemap.c: In function 'clear_bit_unlock_is_negative_byte':
  mm/filemap.c:933:9: error: too few arguments to function 'test_bit'
    return test_bit(PG_waiters);
         ^~~~~~~~

Fixes: b91e1302 ('mm: optimize PageWaiters bit use for unlock_page()')
Signed-off-by: Olof Johansson <olof@lixom.net>
Brown-paper-bag-by: Linus Torvalds <dummy@duh.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In commit 62906027 ("mm: add PageWaiters indicating tasks are
waiting for a page bit") Nick Piggin made our page locking no longer
unconditionally touch the hashed page waitqueue, which not only helps
performance in general, but is particularly helpful on NUMA machines
where the hashed wait queues can bounce around a lot.

However, the "clear lock bit atomically and then test the waiters bit"
sequence turns out to be much more expensive than it needs to be,
because you get a nasty stall when trying to access the same word that
just got updated atomically.

On architectures where locking is done with LL/SC, this would be trivial
to fix with a new primitive that clears one bit and tests another
atomically, but that ends up not working on x86, where the only atomic
operations that return the result end up being cmpxchg and xadd.  The
atomic bit operations return the old value of the same bit we changed,
not the value of an unrelated bit.

On x86, we could put the lock bit in the high bit of the byte, and use
"xadd" with that bit (where the overflow ends up not touching other
bits), and look at the other bits of the result.  However, an even
simpler model is to just use a regular atomic "and" to clear the lock
bit, and then the sign bit in eflags will indicate the resulting state
of the unrelated bit #7.

So by moving the PageWaiters bit up to bit #7, we can atomically clear
the lock bit and test the waiters bit on x86 too.  And architectures
with LL/SC (which is all the usual RISC suspects), the particular bit
doesn't matter, so they are fine with this approach too.

This avoids the extra access to the same atomic word, and thus avoids
the costly stall at page unlock time.

The only downside is that the interface ends up being a bit odd and
specialized: clear a bit in a byte, and test the sign bit.  Nick doesn't
love the resulting name of the new primitive, but I'd rather make the
name be descriptive and very clear about the limitation imposed by
trying to work across all relevant architectures than make it be some
generic thing that doesn't make the odd semantics explicit.

So this introduces the new architecture primitive

    clear_bit_unlock_is_negative_byte();

and adds the trivial implementation for x86.  We have a generic
non-optimized fallback (that just does a "clear_bit()"+"test_bit(7)"
combination) which can be overridden by any architecture that can do
better.  According to Nick, Power has the same hickup x86 has, for
example, but some other architectures may not even care.

All these optimizations mean that my page locking stress-test (which is
just executing a lot of small short-lived shell scripts: "make test" in
the git source tree) no longer makes our page locking look horribly bad.
Before all these optimizations, just the unlock_page() costs were just
over 3% of all CPU overhead on "make test".  After this, it's down to
0.66%, so just a quarter of the cost it used to be.

(The difference on NUMA is bigger, but there this micro-optimization is
likely less noticeable, since the big issue on NUMA was not the accesses
to 'struct page', but the waitqueue accesses that were already removed
by Nick's earlier commit).
Acked-by: Nick Piggin <npiggin@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull crypto fix from Herbert Xu:
 "This fixes a hash corruption bug in the marvell driver"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: marvell - Copy IVDIG before launching partial DMA ahash requests

Pull networking fixes from David Miller:

 1) Various ipvlan fixes from Eric Dumazet and Mahesh Bandewar.

    The most important is to not assume the packet is RX just because
    the destination address matches that of the device. Such an
    assumption causes problems when an interface is put into loopback
    mode.

 2) If we retry when creating a new tc entry (because we dropped the
    RTNL mutex in order to load a module, for example) we end up with
    -EAGAIN and then loop trying to replay the request. But we didn't
    reset some state when looping back to the top like this, and if
    another thread meanwhile inserted the same tc entry we were trying
    to, we re-link it creating an enless loop in the tc chain. Fix from
    Daniel Borkmann.

 3) There are two different WRITE bits in the MDIO address register for
    the stmmac chip, depending upon the chip variant. Due to a bug we
    could set them both, fix from Hock Leong Kweh.

 4) Fix mlx4 bug in XDP_TX handling, from Tariq Toukan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  net: stmmac: fix incorrect bit set in gmac4 mdio addr register
  r8169: add support for RTL8168 series add-on card.
  net: xdp: remove unused bfp_warn_invalid_xdp_buffer()
  openvswitch: upcall: Fix vlan handling.
  ipv4: Namespaceify tcp_tw_reuse knob
  net: korina: Fix NAPI versus resources freeing
  net, sched: fix soft lockup in tc_classify
  net/mlx4_en: Fix user prio field in XDP forward
  tipc: don't send FIN message from connectionless socket
  ipvlan: fix multicast processing
  ipvlan: fix various issues in ipvlan_process_multicast()

In the actual implementation ether_addr_equal function tests for equality to 0
when returning. It seems in commit 0d74c4 it is somehow overlooked to change
this operator to reflect the actual function.
Signed-off-by: Cihangir Akturk <cakturk@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

The 80211.tmpl DocBook file was removed in commit 819bf593 ("docs-rst:
sphinxify 802.11 documentation"), but the 80211.xml target was re-added to
the Makefile by commit 7ddedebb ("ALSA: doc: ReSTize
writing-an-alsa-driver document"), leading to a failure when building the
documentation:

*** No rule to make target 'Documentation/DocBook/80211.xml', needed by
'Documentation/DocBook/80211.aux.xml'.

cc: stable@vger.kernel.org
Signed-off-by: John Brooks <john@fastquake.com>
Mea-culpa-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Linux 4.10-rc1

Fixing the gmac4 mdio write access to use MII_GMAC4_WRITE only instead of
OR together with MII_WRITE.
Signed-off-by: Kweh, Hock Leong <hock.leong.kweh@intel.com>
Acked-By: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This chip is the same as RTL8168, but its device id is 0x8161.
Signed-off-by: Chun-Hao Lin <hau@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After commit 73b62bd0 ("virtio-net:
remove the warning before XDP linearizing"), there's no users for
bpf_warn_invalid_xdp_buffer(), so remove it. This is a revert for
commit f23bc46c.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Networking stack accelerate vlan tag handling by
keeping topmost vlan header in skb. This works as
long as packet remains in OVS datapath. But during
OVS upcall vlan header is pushed on to the packet.
When such packet is sent back to OVS datapath, core
networking stack might not handle it correctly. Following
patch avoids this issue by accelerating the vlan tag
during flow key extract. This simplifies datapath by
bringing uniform packet processing for packets from
all code paths.

Fixes: 5108bbad ("openvswitch: add processing of L3 packets").
CC: Jarno Rajahalme <jarno@ovn.org>
CC: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Different namespaces might have different requirements to reuse
TIME-WAIT sockets for new connections. This might be required in
cases where different namespace applications are in place which
require TIME_WAIT socket connections to be reduced independently
of the host.
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Christopher Covington reported a crash on aarch64 on recent Fedora
kernels:

kernel BUG at ./include/linux/scatterlist.h:140!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
Modules linked in:
CPU: 2 PID: 752 Comm: cryptomgr_test Not tainted 4.9.0-11815-ge93b1cc8 #162
Hardware name: linux,dummy-virt (DT)
task: ffff80007c650080 task.stack: ffff800008910000
PC is at sg_init_one+0xa0/0xb8
LR is at sg_init_one+0x24/0xb8
...
[<ffff000008398db8>] sg_init_one+0xa0/0xb8
[<ffff000008350a44>] test_acomp+0x10c/0x438
[<ffff000008350e20>] alg_test_comp+0xb0/0x118
[<ffff00000834f28c>] alg_test+0x17c/0x2f0
[<ffff00000834c6a4>] cryptomgr_test+0x44/0x50
[<ffff0000080dac70>] kthread+0xf8/0x128
[<ffff000008082ec0>] ret_from_fork+0x10/0x50

The test vectors used for input are part of the kernel image. These
inputs are passed as a buffer to sg_init_one which eventually blows up
with BUG_ON(!virt_addr_valid(buf)). On arm64, virt_addr_valid returns
false for the kernel image since virt_to_page will not return the
correct page. Fix this by copying the input vectors to heap buffer
before setting up the scatterlist.
Reported-by: Christopher Covington <cov@codeaurora.org>
Fixes: d7db7a88 ("crypto: acomp - update testmgr with support for acomp")
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Now that dax_iomap_fault() calls ->iomap_begin() without entry lock, we
can use transaction starting in ext4_iomap_begin() and thus simplify
ext4_dax_fault(). It also provides us proper retries in case of ENOSPC.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Currently ->iomap_begin() handler is called with entry lock held. If the
filesystem held any locks between ->iomap_begin() and ->iomap_end()
(such as ext4 which will want to hold transaction open), this would cause
lock inversion with the iomap_apply() from standard IO path which first
calls ->iomap_begin() and only then calls ->actor() callback which grabs
entry locks for DAX (if it faults when copying from/to user provided
buffers).

Fix the problem by nesting grabbing of entry lock inside ->iomap_begin()
- ->iomap_end() pair.
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>