Patch series "mmu notifier contextual informations", v2.

This patchset adds contextual information, why an invalidation is
happening, to mmu notifier callback.  This is necessary for user of mmu
notifier that wish to maintains their own data structure without having to
add new fields to struct vm_area_struct (vma).

For instance device can have they own page table that mirror the process
address space.  When a vma is unmap (munmap() syscall) the device driver
can free the device page table for the range.

Today we do not have any information on why a mmu notifier call back is
happening and thus device driver have to assume that it is always an
munmap().  This is inefficient at it means that it needs to re-allocate
device page table on next page fault and rebuild the whole device driver
data structure for the range.

Other use case beside munmap() also exist, for instance it is pointless
for device driver to invalidate the device page table when the
invalidation is for the soft dirtyness tracking.  Or device driver can
optimize away mprotect() that change the page table permission access for
the range.

This patchset enables all this optimizations for device drivers.  I do not
include any of those in this series but another patchset I am posting will
leverage this.

The patchset is pretty simple from a code point of view.  The first two
patches consolidate all mmu notifier arguments into a struct so that it is
easier to add/change arguments.  The last patch adds the contextual
information (munmap, protection, soft dirty, clear, ...).

This patch (of 3):

To avoid having to change many callback definition everytime we want to
add a parameter use a structure to group all parameters for the
mmu_notifier invalidate_range_start/end callback.  No functional changes
with this patch.

[akpm@linux-foundation.org: fix drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c kerneldoc]
Link: http://lkml.kernel.org/r/20181205053628.3210-2-jglisse@redhat.comSigned-off-by: NJérôme Glisse <jglisse@redhat.com>
Acked-by: NJan Kara <jack@suse.cz>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>	[infiniband]
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Felix Kuehling <felix.kuehling@amd.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If there are lots of write IO with flash device, it could have a
wearout problem of storage. To overcome the problem, admin needs
to design write limitation to guarantee flash health
for entire product life.

This patch creates a new knob "writeback_limit" for zram.

writeback_limit's default value is 0 so that it doesn't limit
any writeback. If admin want to measure writeback count in a
certain period, he could know it via /sys/block/zram0/bd_stat's
3rd column.

If admin want to limit writeback as per-day 400M, he could do it
like below.

	MB_SHIFT=20
	4K_SHIFT=12
	echo $((400<<MB_SHIFT>>4K_SHIFT)) > \
		/sys/block/zram0/writeback_limit.

If admin want to allow further write again, he could do it like below

	echo 0 > /sys/block/zram0/writeback_limit

If admin want to see remaining writeback budget,

	cat /sys/block/zram0/writeback_limit

The writeback_limit count will reset whenever you reset zram (e.g., system
reboot, echo 1 > /sys/block/zramX/reset) so keeping how many of writeback
happened until you reset the zram to allocate extra writeback budget in
next setting is user's job.

[minchan@kernel.org: v4]
  Link: http://lkml.kernel.org/r/20181203024045.153534-8-minchan@kernel.org
Link: http://lkml.kernel.org/r/20181127055429.251614-8-minchan@kernel.orgSigned-off-by: NMinchan Kim <minchan@kernel.org>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Joey Pabalinas <joeypabalinas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

bd_stat represents things that happened in the backing device.  Currently
it supports bd_counts, bd_reads and bd_writes which are helpful to
understand wearout of flash and memory saving.

[minchan@kernel.org: v4]
  Link: http://lkml.kernel.org/r/20181203024045.153534-7-minchan@kernel.org
Link: http://lkml.kernel.org/r/20181127055429.251614-7-minchan@kernel.orgSigned-off-by: NMinchan Kim <minchan@kernel.org>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Joey Pabalinas <joeypabalinas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a new feature "zram idle/huge page writeback".  In the zram-swap use
case, zram usually has many idle/huge swap pages.  It's pointless to keep
them in memory (ie, zram).

To solve this problem, this feature introduces idle/huge page writeback to
the backing device so the goal is to save more memory space on embedded
systems.

Normal sequence to use idle/huge page writeback feature is as follows,

while (1) {
        # mark allocated zram slot to idle
        echo all > /sys/block/zram0/idle
        # leave system working for several hours
        # Unless there is no access for some blocks on zram,
	# they are still IDLE marked pages.

        echo "idle" > /sys/block/zram0/writeback
	or/and
	echo "huge" > /sys/block/zram0/writeback
        # write the IDLE or/and huge marked slot into backing device
	# and free the memory.
}

Per the discussion at
https://lore.kernel.org/lkml/20181122065926.GG3441@jagdpanzerIV/T/#u,

This patch removes direct incommpressibe page writeback feature
(d2afd25114f4 ("zram: write incompressible pages to backing device")).

Below concerns from Sergey:
== &< ==

"IDLE writeback" is superior to "incompressible writeback".

"incompressible writeback" is completely unpredictable and uncontrollable;
it depens on data patterns and compression algorithms.  While "IDLE
writeback" is predictable.

I even suspect, that, *ideally*, we can remove "incompressible writeback".
"IDLE pages" is a super set which also includes "incompressible" pages.
So, technically, we still can do "incompressible writeback" from "IDLE
writeback" path; but a much more reasonable one, based on a page idling
period.

I understand that you want to keep "direct incompressible writeback"
around.  ZRAM is especially popular on devices which do suffer from flash
wearout, so I can see "incompressible writeback" path becoming a dead
code, long term.

== &< ==

Below concerns from Minchan:
== &< ==

My concern is if we enable CONFIG_ZRAM_WRITEBACK in this implementation,
both hugepage/idlepage writeck will turn on.  However someuser want to
enable only idlepage writeback so we need to introduce turn on/off knob
for hugepage or new CONFIG_ZRAM_IDLEPAGE_WRITEBACK for those usecase.  I
don't want to make it complicated *if possible*.

Long term, I imagine we need to make VM aware of new swap hierarchy a
little bit different with as-is.  For example, first high priority swap
can return -EIO or -ENOCOMP, swap try to fallback to next lower priority
swap device.  With that, hugepage writeback will work tranparently.

So we could regard it as regression because incompressible pages doesn't
go to backing storage automatically.  Instead, user should do it via "echo
huge" > /sys/block/zram/writeback" manually.

== &< ==

Link: http://lkml.kernel.org/r/20181127055429.251614-6-minchan@kernel.orgSigned-off-by: NMinchan Kim <minchan@kernel.org>
Reviewed-by: NJoey Pabalinas <joeypabalinas@gmail.com>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

To support idle page writeback with upcoming patches, this patch
introduces a new ZRAM_IDLE flag.

Userspace can mark zram slots as "idle" via
	"echo all > /sys/block/zramX/idle"
which marks every allocated zram slot as ZRAM_IDLE.
User could see it by /sys/kernel/debug/zram/zram0/block_state.

          300    75.033841 ...i
          301    63.806904 s..i
          302    63.806919 ..hi

Once there is IO for the slot, the mark will be disappeared.

	  300    75.033841 ...
          301    63.806904 s..i
          302    63.806919 ..hi

Therefore, 300th block is idle zpage. With this feature,
user can how many zram has idle pages which are waste of memory.

Link: http://lkml.kernel.org/r/20181127055429.251614-5-minchan@kernel.orgSigned-off-by: NMinchan Kim <minchan@kernel.org>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: NJoey Pabalinas <joeypabalinas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Rename some variables and restructure some code for better readability in
writeback and zs_free_page.

Link: http://lkml.kernel.org/r/20181127055429.251614-4-minchan@kernel.orgSigned-off-by: NMinchan Kim <minchan@kernel.org>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: NJoey Pabalinas <joeypabalinas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If blkdev_get fails, we shouldn't do blkdev_put.  Otherwise, kernel emits
below log.  This patch fixes it.

  WARNING: CPU: 0 PID: 1893 at fs/block_dev.c:1828 blkdev_put+0x105/0x120
  Modules linked in:
  CPU: 0 PID: 1893 Comm: swapoff Not tainted 4.19.0+ #453
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
  RIP: 0010:blkdev_put+0x105/0x120
  Call Trace:
    __x64_sys_swapoff+0x46d/0x490
    do_syscall_64+0x5a/0x190
    entry_SYSCALL_64_after_hwframe+0x49/0xbe
  irq event stamp: 4466
  hardirqs last  enabled at (4465):  __free_pages_ok+0x1e3/0x490
  hardirqs last disabled at (4466):  trace_hardirqs_off_thunk+0x1a/0x1c
  softirqs last  enabled at (3420):  __do_softirq+0x333/0x446
  softirqs last disabled at (3407):  irq_exit+0xd1/0xe0

Link: http://lkml.kernel.org/r/20181127055429.251614-3-minchan@kernel.orgSigned-off-by: NMinchan Kim <minchan@kernel.org>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: NJoey Pabalinas <joeypabalinas@gmail.com>
Cc: <stable@vger.kernel.org>	[4.14+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "zram idle page writeback", v3.

Inherently, swap device has many idle pages which are rare touched since
it was allocated.  It is never problem if we use storage device as swap.
However, it's just waste for zram-swap.

This patchset supports zram idle page writeback feature.

* Admin can define what is idle page "no access since X time ago"
* Admin can define when zram should writeback them
* Admin can define when zram should stop writeback to prevent wearout

Details are in each patch's description.

This patch (of 7):

  ================================
  WARNING: inconsistent lock state
  4.19.0+ #390 Not tainted
  --------------------------------
  inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
  zram_verify/2095 [HC0[0]:SC1[1]:HE1:SE0] takes:
  00000000b1828693 (&(&zram->bitmap_lock)->rlock){+.?.}, at: put_entry_bdev+0x1e/0x50
  {SOFTIRQ-ON-W} state was registered at:
    _raw_spin_lock+0x2c/0x40
    zram_make_request+0x755/0xdc9
    generic_make_request+0x373/0x6a0
    submit_bio+0x6c/0x140
    __swap_writepage+0x3a8/0x480
    shrink_page_list+0x1102/0x1a60
    shrink_inactive_list+0x21b/0x3f0
    shrink_node_memcg.constprop.99+0x4f8/0x7e0
    shrink_node+0x7d/0x2f0
    do_try_to_free_pages+0xe0/0x300
    try_to_free_pages+0x116/0x2b0
    __alloc_pages_slowpath+0x3f4/0xf80
    __alloc_pages_nodemask+0x2a2/0x2f0
    __handle_mm_fault+0x42e/0xb50
    handle_mm_fault+0x55/0xb0
    __do_page_fault+0x235/0x4b0
    page_fault+0x1e/0x30
  irq event stamp: 228412
  hardirqs last  enabled at (228412): [<ffffffff98245846>] __slab_free+0x3e6/0x600
  hardirqs last disabled at (228411): [<ffffffff98245625>] __slab_free+0x1c5/0x600
  softirqs last  enabled at (228396): [<ffffffff98e0031e>] __do_softirq+0x31e/0x427
  softirqs last disabled at (228403): [<ffffffff98072051>] irq_exit+0xd1/0xe0

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(&(&zram->bitmap_lock)->rlock);
    <Interrupt>
      lock(&(&zram->bitmap_lock)->rlock);

   *** DEADLOCK ***

  no locks held by zram_verify/2095.

  stack backtrace:
  CPU: 5 PID: 2095 Comm: zram_verify Not tainted 4.19.0+ #390
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
  Call Trace:
   <IRQ>
   dump_stack+0x67/0x9b
   print_usage_bug+0x1bd/0x1d3
   mark_lock+0x4aa/0x540
   __lock_acquire+0x51d/0x1300
   lock_acquire+0x90/0x180
   _raw_spin_lock+0x2c/0x40
   put_entry_bdev+0x1e/0x50
   zram_free_page+0xf6/0x110
   zram_slot_free_notify+0x42/0xa0
   end_swap_bio_read+0x5b/0x170
   blk_update_request+0x8f/0x340
   scsi_end_request+0x2c/0x1e0
   scsi_io_completion+0x98/0x650
   blk_done_softirq+0x9e/0xd0
   __do_softirq+0xcc/0x427
   irq_exit+0xd1/0xe0
   do_IRQ+0x93/0x120
   common_interrupt+0xf/0xf
   </IRQ>

With writeback feature, zram_slot_free_notify could be called in softirq
context by end_swap_bio_read.  However, bitmap_lock is not aware of that
so lockdep yell out:

  get_entry_bdev
  spin_lock(bitmap->lock);
  irq
  softirq
  end_swap_bio_read
  zram_slot_free_notify
  zram_slot_lock <-- deadlock prone
  zram_free_page
  put_entry_bdev
  spin_lock(bitmap->lock); <-- deadlock prone

With akpm's suggestion (i.e.  bitmap operation is already atomic), we
could remove bitmap lock.  It might fail to find a empty slot if serious
contention happens.  However, it's not severe problem because huge page
writeback has already possiblity to fail if there is severe memory
pressure.  Worst case is just keeping the incompressible in memory, not
storage.

The other problem is zram_slot_lock in zram_slot_slot_free_notify.  To
make it safe is this patch introduces zram_slot_trylock where
zram_slot_free_notify uses it.  Although it's rare to be contented, this
patch adds new debug stat "miss_free" to keep monitoring how often it
happens.

Link: http://lkml.kernel.org/r/20181127055429.251614-2-minchan@kernel.orgSigned-off-by: NMinchan Kim <minchan@kernel.org>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: NJoey Pabalinas <joeypabalinas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Userspace should always be in charge of how to online memory and if memory
should be onlined automatically in the kernel.  Let's drop the parameter
to overwrite this - XEN passes memhp_auto_online, just like add_memory(),
so we can directly use that instead internally.

Link: http://lkml.kernel.org/r/20181123123740.27652-1-david@redhat.comSigned-off-by: NDavid Hildenbrand <david@redhat.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NOscar Salvador <osalvador@suse.de>
Acked-by: NJuergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In cb5e39b8 ("drivers: base: refactor add_memory_section() to
add_memory_block()"), add_memory_block() is introduced, which is only
invoked in memory_dev_init().

When combining these two loops in memory_dev_init() and
add_memory_block(), they looks like this:

    for (i = 0; i < NR_MEM_SECTIONS; i += sections_per_block)
        for (j = i;
	    (j < i + sections_per_block) && j < NR_MEM_SECTIONS;
	    j++)

Since it is sure the (i < NR_MEM_SECTIONS) and j sits in its own memory
block, the check of (j < NR_MEM_SECTIONS) is not necessary.

This patch just removes this check.

Link: http://lkml.kernel.org/r/20181123222811.18216-1-richard.weiyang@gmail.comSigned-off-by: NWei Yang <richard.weiyang@gmail.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Seth Jennings <sjenning@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

At Maintainer Summit, Greg brought up a topic I proposed around
EXPORT_SYMBOL_GPL usage.  The motivation was considerations for when
EXPORT_SYMBOL_GPL is warranted and the criteria for taking the exceptional
step of reclassifying an existing export.  Specifically, I wanted to make
the case that although the line is fuzzy and hard to specify in abstract
terms, it is nonetheless clear that devm_memremap_pages() and HMM
(Heterogeneous Memory Management) have crossed it.  The
devm_memremap_pages() facility should have been EXPORT_SYMBOL_GPL from the
beginning, and HMM as a derivative of that functionality should have
naturally picked up that designation as well.

Contrary to typical rules, the HMM infrastructure was merged upstream with
zero in-tree consumers.  There was a promise at the time that those users
would be merged "soon", but it has been over a year with no drivers
arriving.  While the Nouveau driver is about to belatedly make good on
that promise it is clear that HMM was targeted first and foremost at an
out-of-tree consumer.

HMM is derived from devm_memremap_pages(), a facility Christoph and I
spearheaded to support persistent memory.  It combines a device lifetime
model with a dynamically created 'struct page' / memmap array for any
physical address range.  It enables coordination and control of the many
code paths in the kernel built to interact with memory via 'struct page'
objects.  With HMM the integration goes even deeper by allowing device
drivers to hook and manipulate page fault and page free events.

One interpretation of when EXPORT_SYMBOL is suitable is when it is
exporting stable and generic leaf functionality.  The
devm_memremap_pages() facility continues to see expanding use cases,
peer-to-peer DMA being the most recent, with no clear end date when it
will stop attracting reworks and semantic changes.  It is not suitable to
export devm_memremap_pages() as a stable 3rd party driver API due to the
fact that it is still changing and manipulates core behavior.  Moreover,
it is not in the best interest of the long term development of the core
memory management subsystem to permit any external driver to effectively
define its own system-wide memory management policies with no
encouragement to engage with upstream.

I am also concerned that HMM was designed in a way to minimize further
engagement with the core-MM.  That, with these hooks in place,
device-drivers are free to implement their own policies without much
consideration for whether and how the core-MM could grow to meet that
need.  Going forward not only should HMM be EXPORT_SYMBOL_GPL, but the
core-MM should be allowed the opportunity and stimulus to change and
address these new use cases as first class functionality.

Original changelog:

hmm_devmem_add(), and hmm_devmem_add_resource() duplicated
devm_memremap_pages() and are now simple now wrappers around the core
facility to inject a dev_pagemap instance into the global pgmap_radix and
hook page-idle events.  The devm_memremap_pages() interface is base
infrastructure for HMM.  HMM has more and deeper ties into the kernel
memory management implementation than base ZONE_DEVICE which is itself a
EXPORT_SYMBOL_GPL facility.

Originally, the HMM page structure creation routines copied the
devm_memremap_pages() code and reused ZONE_DEVICE.  A cleanup to unify the
implementations was discussed during the initial review:
http://lkml.iu.edu/hypermail/linux/kernel/1701.2/00812.html Recent work to
extend devm_memremap_pages() for the peer-to-peer-DMA facility enabled
this cleanup to move forward.

In addition to the integration with devm_memremap_pages() HMM depends on
other GPL-only symbols:

    mmu_notifier_unregister_no_release
    percpu_ref
    region_intersects
    __class_create

It goes further to consume / indirectly expose functionality that is not
exported to any other driver:

    alloc_pages_vma
    walk_page_range

HMM is derived from devm_memremap_pages(), and extends deep core-kernel
fundamentals. Similar to devm_memremap_pages(), mark its entry points
EXPORT_SYMBOL_GPL().

[logang@deltatee.com: PCI/P2PDMA: match interface changes to devm_memremap_pages()]
  Link: http://lkml.kernel.org/r/20181130225911.2900-1-logang@deltatee.com
Link: http://lkml.kernel.org/r/154275560565.76910.15919297436557795278.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>,
Cc: Michal Hocko <mhocko@suse.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The last step before devm_memremap_pages() returns success is to allocate
a release action, devm_memremap_pages_release(), to tear the entire setup
down.  However, the result from devm_add_action() is not checked.

Checking the error from devm_add_action() is not enough.  The api
currently relies on the fact that the percpu_ref it is using is killed by
the time the devm_memremap_pages_release() is run.  Rather than continue
this awkward situation, offload the responsibility of killing the
percpu_ref to devm_memremap_pages_release() directly.  This allows
devm_memremap_pages() to do the right thing relative to init failures and
shutdown.

Without this change we could fail to register the teardown of
devm_memremap_pages().  The likelihood of hitting this failure is tiny as
small memory allocations almost always succeed.  However, the impact of
the failure is large given any future reconfiguration, or disable/enable,
of an nvdimm namespace will fail forever as subsequent calls to
devm_memremap_pages() will fail to setup the pgmap_radix since there will
be stale entries for the physical address range.

An argument could be made to require that the ->kill() operation be set in
the @pgmap arg rather than passed in separately.  However, it helps code
readability, tracking the lifetime of a given instance, to be able to grep
the kill routine directly at the devm_memremap_pages() call site.

Link: http://lkml.kernel.org/r/154275558526.76910.7535251937849268605.stgit@dwillia2-desk3.amr.corp.intel.comSigned-off-by: NDan Williams <dan.j.williams@intel.com>
Fixes: e8d51348 ("memremap: change devm_memremap_pages interface...")
Reviewed-by: N"Jérôme Glisse" <jglisse@redhat.com>
Reported-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

totalram_pages and totalhigh_pages are made static inline function.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes
better to remove the lock and convert variables to atomic, with preventing
poteintial store-to-read tearing as a bonus.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.orgSigned-off-by: NArun KS <arunks@codeaurora.org>
Suggested-by: NMichal Hocko <mhocko@suse.com>
Suggested-by: NVlastimil Babka <vbabka@suse.cz>
Reviewed-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: NPavel Tatashin <pasha.tatashin@soleen.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

totalram_pages, zone->managed_pages and totalhigh_pages updates are
protected by managed_page_count_lock, but readers never care about it.
Convert these variables to atomic to avoid readers potentially seeing a
store tear.

This patch converts zone->managed_pages.  Subsequent patches will convert
totalram_panges, totalhigh_pages and eventually managed_page_count_lock
will be removed.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes
better to remove the lock and convert variables to atomic, with preventing
poteintial store-to-read tearing as a bonus.

Link: http://lkml.kernel.org/r/1542090790-21750-3-git-send-email-arunks@codeaurora.orgSigned-off-by: NArun KS <arunks@codeaurora.org>
Suggested-by: NMichal Hocko <mhocko@suse.com>
Suggested-by: NVlastimil Babka <vbabka@suse.cz>
Reviewed-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Reviewed-by: NPavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "mm: convert totalram_pages, totalhigh_pages and managed
pages to atomic", v5.

This series converts totalram_pages, totalhigh_pages and
zone->managed_pages to atomic variables.

totalram_pages, zone->managed_pages and totalhigh_pages updates are
protected by managed_page_count_lock, but readers never care about it.
Convert these variables to atomic to avoid readers potentially seeing a
store tear.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 It seemes better
to remove the lock and convert variables to atomic.  With the change,
preventing poteintial store-to-read tearing comes as a bonus.

This patch (of 4):

This is in preparation to a later patch which converts totalram_pages and
zone->managed_pages to atomic variables.  Please note that re-reading the
value might lead to a different value and as such it could lead to
unexpected behavior.  There are no known bugs as a result of the current
code but it is better to prevent from them in principle.

Link: http://lkml.kernel.org/r/1542090790-21750-2-git-send-email-arunks@codeaurora.orgSigned-off-by: NArun KS <arunks@codeaurora.org>
Reviewed-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Reviewed-by: NPavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The two different assignments for pkt_len are actually the same and
so the if statement is redundant and can be removed.  Masking a u8
return value from inb() with 0xFF is also redundant and can also be
emoved.

Similarly, the two different outb calls are identical as the mask
of 0xff on the second outb is redundant since a u8 is being written,
so the if statement is also redundant and can be also removed.

Detected by CoverityScan, CID#1475639 ("Identical code for different
branches")

V2: Remove the if statement for the outb calls, thanks to David
Miller for spotting this.
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This happened when I tried to boot normal Fedora 29 system with latest
available kernel (from fedora rawhide, plus some unrelated custom
patches):

	BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
	PGD 0 P4D 0
	Oops: 0010 [#1] SMP PTI
	CPU: 6 PID: 1422 Comm: libvirtd Tainted: G          I       4.20.0-0.rc7.git3.hpsa2.1.fc29.x86_64 #1
	Hardware name: HP ProLiant BL460c G6, BIOS I24 05/21/2018
	RIP: 0010:          (null)
	Code: Bad RIP value.
	RSP: 0018:ffffa47ccdc9fbe0 EFLAGS: 00010246
	RAX: 0000000000000000 RBX: 00000000000003e8 RCX: ffffa47ccdc9fbf8
	RDX: ffffa47ccdc9fc00 RSI: ffff97d9ee7b01f8 RDI: ffff97d9f0150b80
	RBP: ffff97d9f0150b80 R08: 0000000000000000 R09: 0000000000000000
	R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000003
	R13: ffff97d9ef1e53e8 R14: 0000000000000009 R15: ffff97d9f0ac6730
	FS:  00007f4d224ef700(0000) GS:ffff97d9fa200000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
	CR2: ffffffffffffffd6 CR3: 00000011ece52006 CR4: 00000000000206e0
	Call Trace:
	 ? bnx2x_chip_cleanup+0x195/0x610 [bnx2x]
	 ? bnx2x_nic_unload+0x1e2/0x8f0 [bnx2x]
	 ? bnx2x_reload_if_running+0x24/0x40 [bnx2x]
	 ? bnx2x_set_features+0x79/0xa0 [bnx2x]
	 ? __netdev_update_features+0x244/0x9e0
	 ? netlink_broadcast_filtered+0x136/0x4b0
	 ? netdev_update_features+0x22/0x60
	 ? dev_disable_lro+0x1c/0xe0
	 ? devinet_sysctl_forward+0x1c6/0x211
	 ? proc_sys_call_handler+0xab/0x100
	 ? __vfs_write+0x36/0x1a0
	 ? rcu_read_lock_sched_held+0x79/0x80
	 ? rcu_sync_lockdep_assert+0x2e/0x60
	 ? __sb_start_write+0x14c/0x1b0
	 ? vfs_write+0x159/0x1c0
	 ? vfs_write+0xba/0x1c0
	 ? ksys_write+0x52/0xc0
	 ? do_syscall_64+0x60/0x1f0
	 ? entry_SYSCALL_64_after_hwframe+0x49/0xbe

After some investigation I figured out that recently added cleanup code
tries to call VLAN filtering de-initialization function which exist only
for newer hardware. Corresponding function pointer is not
set (== 0) for older hardware, namely these chips:

	#define CHIP_NUM_57710			0x164e
	#define CHIP_NUM_57711			0x164f
	#define CHIP_NUM_57711E			0x1650

And I have one of those in my test system:

	Broadcom Inc. and subsidiaries NetXtreme II BCM57711E 10-Gigabit PCIe [14e4:1650]

Function bnx2x_init_vlan_mac_fp_objs() from
drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h decides whether to
initialize relevant pointers in bnx2x_sp_objs.vlan_obj or not.

This regression was introduced after v4.20-rc7, and still exists in v4.20
release.

Fixes: 04f05230 ("bnx2x: Remove configured vlans as part of unload sequence.")
Signed-off-by: NIvan Mironov <mironov.ivan@gmail.com>
Signed-off-by: NIvan Mironov <mironov.ivan@gmail.com>
Acked-by: NSudarsana Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drop LIST_HEAD where the variable it declares has never
been used.

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

// <smpl>
@@
identifier x;
@@
- LIST_HEAD(x);
  ... when != x
// </smpl>

Fixes: c82e9aa0 ("mlx4_core: resource tracking for HCA resources used by guests")
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drop LIST_HEAD where the variable it declares is never used.

The uses were removed in 244cd96a ("net_sched: remove
list_head from tc_action"), but not the declaration.

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

// <smpl>
@@
identifier x;
@@
- LIST_HEAD(x);
  ... when != x
// </smpl>

Fixes: 244cd96a ("net_sched: remove list_head from tc_action")
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drop LIST_HEAD where the variable it declares is never used.

These became useless in 244cd96a ("net_sched: remove list_head
from tc_action")

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

// <smpl>
@@
identifier x;
@@
- LIST_HEAD(x);
  ... when != x
// </smpl>

Fixes: 244cd96a ("net_sched: remove list_head from tc_action")
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx5/core/en_rep.c:1339:57-58: Unneeded semicolon

 Remove unneeded semicolon.

Generated by: scripts/coccinelle/misc/semicolon.cocci

Fixes: 4c8fb298 ("net/mlx5e: Increase VF representors' SQ size to 128")
CC: Gavi Teitz <gavi@mellanox.com>
Signed-off-by: Nkbuild test robot <fengguang.wu@intel.com>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb->sp doesn't exist anymore in the next-next tree, so mips defconfig
no longer builds.  Use helper instead to reset the secpath.

Not even compile tested.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Fixes: 4165079b ("net: switch secpath to use skb extension infrastructure")
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

i.MX PWM module's ipg_clk_s is for PWM register access, on most of i.MX
SoCs, this ipg_clk_s is from system ipg clock or perclk which is always
enabled, but on i.MX7D, the ipg_clk_s is from PWM1_CLK_ROOT which is
controlled by CCGR132, that means the CCGR132 MUST be enabled first
before accessing PWM registers on i.MX7D. This patch adds ipg clock
operation to make sure register access successfully on i.MX7D and it
fixes Linux kernel boot up hang during PWM driver probe.

Fixes: 4a23e6ee ("ARM: dts: imx7d-sdb: Restore pwm backlight support")
Signed-off-by: NAnson Huang <Anson.Huang@nxp.com>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Adopt the SPDX license identifier headers to ease license compliance
management.
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Commit e39c0df1 ("pwm: Introduce the pwm_args concept") has
changed the variable for the period for clps711x-pwm driver, so now
pwm_get/set_period() works with pwm->state.period variable instead
of pwm->args.period.
This patch changes the period variable in other places where it is used.
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Adopt the SPDX license identifier headers to ease license compliance
management.

Cc: Bart Tanghe <bart.tanghe@thomasmore.be>
Signed-off-by: NStefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: NEric Anholt <eric@anholt.net>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

The Cygnus architecture uses a Kona PWM. This is already present in the
device tree but can't be built actually. Hence, allow the Kona PWM to
be built for the Cygnus architecture.
Signed-off-by: NClément Péron <peron.clem@gmail.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NScott Branden <scott.branden@broadcom.com>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NThierry Reding <thierry.reding@gmail.com>

Remove dead code related to internal IV generators, which are no longer
used since they've been replaced with the "seqiv" and "echainiv"
templates.  The removed code includes:

- The "givcipher" (GIVCIPHER) algorithm type.  No algorithms are
  registered with this type anymore, so it's unneeded.

- The "const char *geniv" member of aead_alg, ablkcipher_alg, and
  blkcipher_alg.  A few algorithms still set this, but it isn't used
  anymore except to show via /proc/crypto and CRYPTO_MSG_GETALG.
  Just hardcode "<default>" or "<none>" in those cases.

- The 'skcipher_givcrypt_request' structure, which is never used.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Fixes: cf718eaa ("crypto: cavium/nitrox - Enabled Mailbox support")
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Added support to offload AEAD ciphers to NITROX. Currently supported
AEAD cipher is 'gcm(aes)'.
Signed-off-by: NNagadheeraj Rottela <rnagadheeraj@marvell.com>
Reviewed-by: NSrikanth Jampala <jsrikanth@marvell.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

The following build warnings are seen when building for ARM64 allmodconfig:

drivers/crypto/mxc-scc.c:181:20: warning: format '%d' expects argument of type 'int', but argument 5 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
drivers/crypto/mxc-scc.c:186:21: warning: format '%d' expects argument of type 'int', but argument 4 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
drivers/crypto/mxc-scc.c:277:21: warning: format '%d' expects argument of type 'int', but argument 4 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
drivers/crypto/mxc-scc.c:339:3: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
drivers/crypto/mxc-scc.c:340:3: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]

Fix them by using the %zu specifier to print a size_t variable and using
a plain %x to print the result of a readl().
Signed-off-by: NFabio Estevam <festevam@gmail.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Fix error counter increment in AEAD decrypt operation when
validation of tag is done in Driver instead of H/W.
Signed-off-by: NHarsh Jain <harsh@chelsio.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Reset the counters on receiving detach from Cxgb4.
Signed-off-by: NAtul Gupta <atul.gupta@chelsio.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

chcr receives "CXGB4_STATE_DETACH" event on PCI Shutdown.
Wait for processing of inflight request and Mark the device unavailable.
Signed-off-by: NHarsh Jain <harsh@chelsio.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Send dma address as value to function arguments instead of pointer.
Signed-off-by: NHarsh Jain <harsh@chelsio.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Use tx_channel_id instead of rx_channel_id.
Signed-off-by: NHarsh Jain <harsh@chelsio.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Send input as IV | AAD | Data. It will allow sending IV as Immediate
Data and Creates space in Work request to add more dma mapped entries.
Signed-off-by: NHarsh Jain <harsh@chelsio.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/crypto/chelsio/chcr_ipsec.c: In function 'chcr_ipsec_xmit':
drivers/crypto/chelsio/chcr_ipsec.c:674:33: warning:
 variable 'kctx_len' set but not used [-Wunused-but-set-variable]
  unsigned int flits = 0, ndesc, kctx_len;

It not used since commit 8362ea16 ("crypto: chcr - ESN for Inline IPSec Tx")
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Clang warns when one enumerated type is implicitly converted to another:

drivers/crypto/ux500/hash/hash_core.c:169:4: warning: implicit
conversion from enumeration type 'enum dma_data_direction' to different
enumeration type 'enum dma_transfer_direction' [-Wenum-conversion]
                        direction, DMA_CTRL_ACK | DMA_PREP_INTERRUPT);
                        ^~~~~~~~~
1 warning generated.

dmaengine_prep_slave_sg expects an enum from dma_transfer_direction.
We know that the only direction supported by this function is
DMA_TO_DEVICE because of the check at the top of this function so we can
just use the equivalent value from dma_transfer_direction.

DMA_TO_DEVICE = DMA_MEM_TO_DEV = 1
Signed-off-by: NNathan Chancellor <natechancellor@gmail.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Clang warns when one enumerated type is implicitly converted to another:

drivers/crypto/ux500/cryp/cryp_core.c:559:5: warning: implicit
conversion from enumeration type 'enum dma_data_direction' to different
enumeration type 'enum dma_transfer_direction' [-Wenum-conversion]
                                direction, DMA_CTRL_ACK);
                                ^~~~~~~~~
drivers/crypto/ux500/cryp/cryp_core.c:583:5: warning: implicit
conversion from enumeration type 'enum dma_data_direction' to different
enumeration type 'enum dma_transfer_direction' [-Wenum-conversion]
                                direction,
                                ^~~~~~~~~
2 warnings generated.

dmaengine_prep_slave_sg expects an enum from dma_transfer_direction.
Because we know the value of the dma_data_direction enum from the
switch statement, we can just use the proper value from
dma_transfer_direction so there is no more conversion.

DMA_TO_DEVICE = DMA_MEM_TO_DEV = 1
DMA_FROM_DEVICE = DMA_DEV_TO_MEM = 2
Signed-off-by: NNathan Chancellor <natechancellor@gmail.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>