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Author SHA1 Message Date
Oscar Salvador
7b0e0c0e35 mm/page_alloc.c: clean up check_for_memory()
check_for_memory() looks a bit confusing.  First of all, we have this:

if (N_MEMORY == N_NORMAL_MEMORY)
	return;

Checking the ENUM declaration, looks like N_MEMORY canot be equal to
N_NORMAL_MEMORY.

I could not find where N_MEMORY is set to N_NORMAL_MEMORY, or the other
way around either, so unless I am missing something, this condition will
never evaluate to true.  It makes sense to get rid of it.

Moving forward, the operations within the loop look a bit confusing as
well.

We set N_HIGH_MEMORY unconditionally, and then we set N_NORMAL_MEMORY in
case we have CONFIG_HIGHMEM (N_NORMAL_MEMORY != N_HIGH_MEMORY) and zone <=
ZONE_NORMAL.  (N_HIGH_MEMORY falls back to N_NORMAL_MEMORY on
!CONFIG_HIGHMEM systems, and that is why we can just go ahead and set
N_HIGH_MEMORY unconditionally)

Although this works, it is a bit subtle.

I think that this could be easier to follow:

First, we should only set N_HIGH_MEMORY in case we have CONFIG_HIGHMEM.
And then we should set N_NORMAL_MEMORY in case zone <= ZONE_NORMAL,
without further checking whether we have CONFIG_HIGHMEM or not.

Link: http://lkml.kernel.org/r/20180828210158.4617-1-osalvador@techadventures.net
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michael Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Huang Ying
979aafa591 mm/swapfile.c: clear si->swap_map[] in swap_free_cluster()
si->swap_map[] of the swap entries in cluster needs to be cleared during
freeing.  Previously, this is done in the caller of swap_free_cluster().
This may cause code duplication (one user now, will add more users later)
and lock/unlock cluster unnecessarily.  In this patch, the clearing code
is moved to swap_free_cluster() to avoid the downside.

Link: http://lkml.kernel.org/r/20180827075535.17406-4-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Huang Ying
10e364da10 mm/swapfile.c: call free_swap_slot() in __swap_entry_free()
This is a code cleanup patch without functionality change.

Originally, when __swap_entry_free() is called, and its return value is 0,
free_swap_slot() will always be called to free the swap entry to the
per-CPU pool.  So move the call to free_swap_slot() to __swap_entry_free()
to simplify the code.

Link: http://lkml.kernel.org/r/20180827075535.17406-3-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Huang Ying
bcd49e8671 mm/swapfile.c: use __try_to_reclaim_swap() in free_swap_and_cache()
The code path to reclaim the swap entry in free_swap_and_cache() is
almost same as that of __try_to_reclaim_swap().  The largest
difference is just coding style.  So the support to the additional
requirement of free_swap_and_cache() is added into
__try_to_reclaim_swap().  free_swap_and_cache() is changed to call
__try_to_reclaim_swap(), and delete the duplicated code.  This will
improve code readability and reduce the potential bugs.

There are 2 functionality differences between __try_to_reclaim_swap()
and swap entry reclaim code of free_swap_and_cache().

- free_swap_and_cache() only reclaims the swap entry if the page is
  unmapped or swap is getting full.  The support has been added into
  __try_to_reclaim_swap().

- try_to_free_swap() (called by __try_to_reclaim_swap()) checks
  pm_suspended_storage(), while free_swap_and_cache() not.  I think
  this is OK.  Because the page and the swap entry can be reclaimed
  later eventually.

Link: http://lkml.kernel.org/r/20180827075535.17406-2-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Vincent Whitchurch
154221c3e5 kmemleak: add module param to print warnings to dmesg
Currently, kmemleak only prints the number of suspected leaks to dmesg but
requires the user to read a debugfs file to get the actual stack traces of
the objects' allocation points.  Add a module option to print the full
object information to dmesg too.  It can be enabled with
kmemleak.verbose=1 on the kernel command line, or "echo 1 >
/sys/module/kmemleak/parameters/verbose":

This allows easier integration of kmemleak into test systems: We have
automated test infrastructure to test our Linux systems.  With this
option, running our tests with kmemleak is as simple as enabling kmemleak
and passing this command line option; the test infrastructure knows how to
save kernel logs, which will now include kmemleak reports.  Without this
option, the test infrastructure needs to be specifically taught to read
out the kmemleak debugfs file.  Removing this need for special handling
makes kmemleak more similar to other kernel debug options (slab debugging,
debug objects, etc).

Link: http://lkml.kernel.org/r/20180903144046.21023-1-vincent.whitchurch@axis.com
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Michal Hocko
4e15a073a1 Revert "mm, mmu_notifier: annotate mmu notifiers with blockable invalidate callbacks"
Revert 5ff7091f5a ("mm, mmu_notifier: annotate mmu notifiers with
blockable invalidate callbacks").

MMU_INVALIDATE_DOES_NOT_BLOCK flags was the only one used and it is no
longer needed since 93065ac753 ("mm, oom: distinguish blockable mode for
mmu notifiers").  We now have a full support for per range !blocking
behavior so we can drop the stop gap workaround which the per notifier
flag was used for.

Link: http://lkml.kernel.org/r/20180827112623.8992-4-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Michal Hocko
15f570bf3d mm,page_alloc: PF_WQ_WORKER threads must sleep at should_reclaim_retry()
Tetsuo Handa has reported that it is possible to bypass the short sleep
for PF_WQ_WORKER threads which was introduced by commit 373ccbe592
("mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make
any progress") and lock up the system if OOM.

The primary reason is that WQ_MEM_RECLAIM WQs are not guaranteed to run
even when they have a rescuer available.  Those workers might be essential
for reclaim to make a forward progress, however.  If we are too unlucky
all the allocations requests can get stuck waiting for a WQ_MEM_RECLAIM
work item and the system is essentially stuck in an OOM condition without
much hope to move on.  Tetsuo has seen the reclaim stuck on
drain_local_pages_wq or xlog_cil_push_work (xfs).  There might be others.

Since should_reclaim_retry() should be a natural reschedule point,
let's do the short sleep for PF_WQ_WORKER threads unconditionally in
order to guarantee that other pending work items are started.  This
will workaround this problem and it is less fragile than hunting down
when the sleep is missed.  Having a single sleeping point is more
robust.

[akpm@linux-foundation.org: reflow comment to 80 cols to save a couple of lines]
Link: http://lkml.kernel.org/r/20180827135101.15700-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Debugged-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Roman Gushchin
68600f623d mm: don't miss the last page because of round-off error
I've noticed, that dying memory cgroups are often pinned in memory by a
single pagecache page.  Even under moderate memory pressure they sometimes
stayed in such state for a long time.  That looked strange.

My investigation showed that the problem is caused by applying the LRU
pressure balancing math:

  scan = div64_u64(scan * fraction[lru], denominator),

where

  denominator = fraction[anon] + fraction[file] + 1.

Because fraction[lru] is always less than denominator, if the initial scan
size is 1, the result is always 0.

This means the last page is not scanned and has
no chances to be reclaimed.

Fix this by rounding up the result of the division.

In practice this change significantly improves the speed of dying cgroups
reclaim.

[guro@fb.com: prevent double calculation of DIV64_U64_ROUND_UP() arguments]
  Link: http://lkml.kernel.org/r/20180829213311.GA13501@castle
Link: http://lkml.kernel.org/r/20180827162621.30187-3-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Roman Gushchin
591edfb10a mm: drain memcg stocks on css offlining
Memcg charge is batched using per-cpu stocks, so an offline memcg can be
pinned by a cached charge up to a moment, when a process belonging to some
other cgroup will charge some memory on the same cpu.  In other words,
cached charges can prevent a memory cgroup from being reclaimed for some
time, without any clear need.

Let's optimize it by explicit draining of all stocks on css offlining.  As
draining is performed asynchronously, and is skipped if any parallel
draining is happening, it's cheap.

Link: http://lkml.kernel.org/r/20180827162621.30187-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Aaron Tomlin
c5fd3ca06b slub: extend slub debug to handle multiple slabs
Extend the slub_debug syntax to "slub_debug=<flags>[,<slub>]*", where
<slub> may contain an asterisk at the end.  For example, the following
would poison all kmalloc slabs:

	slub_debug=P,kmalloc*

and the following would apply the default flags to all kmalloc and all
block IO slabs:

	slub_debug=,bio*,kmalloc*

Please note that a similar patch was posted by Iliyan Malchev some time
ago but was never merged:

	https://marc.info/?l=linux-mm&m=131283905330474&w=2

Link: http://lkml.kernel.org/r/20180928111139.27962-1-atomlin@redhat.com
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Iliyan Malchev <malchev@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Dmitry Vyukov
61448479a9 mm: don't warn about large allocations for slab
Slub does not call kmalloc_slab() for sizes > KMALLOC_MAX_CACHE_SIZE,
instead it falls back to kmalloc_large().

For slab KMALLOC_MAX_CACHE_SIZE == KMALLOC_MAX_SIZE and it calls
kmalloc_slab() for all allocations relying on NULL return value for
over-sized allocations.

This inconsistency leads to unwanted warnings from kmalloc_slab() for
over-sized allocations for slab.  Returning NULL for failed allocations is
the expected behavior.

Make slub and slab code consistent by checking size >
KMALLOC_MAX_CACHE_SIZE in slab before calling kmalloc_slab().

While we are here also fix the check in kmalloc_slab().  We should check
against KMALLOC_MAX_CACHE_SIZE rather than KMALLOC_MAX_SIZE.  It all kinda
worked because for slab the constants are the same, and slub always checks
the size against KMALLOC_MAX_CACHE_SIZE before kmalloc_slab().  But if we
get there with size > KMALLOC_MAX_CACHE_SIZE anyhow bad things will
happen.  For example, in case of a newly introduced bug in slub code.

Also move the check in kmalloc_slab() from function entry to the size >
192 case.  This partially compensates for the additional check in slab
code and makes slub code a bit faster (at least theoretically).

Also drop __GFP_NOWARN in the warning check.  This warning means a bug in
slab code itself, user-passed flags have nothing to do with it.

Nothing of this affects slob.

Link: http://lkml.kernel.org/r/20180927171502.226522-1-dvyukov@gmail.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: syzbot+87829a10073277282ad1@syzkaller.appspotmail.com
Reported-by: syzbot+ef4e8fc3a06e9019bb40@syzkaller.appspotmail.com
Reported-by: syzbot+6e438f4036df52cbb863@syzkaller.appspotmail.com
Reported-by: syzbot+8574471d8734457d98aa@syzkaller.appspotmail.com
Reported-by: syzbot+af1504df0807a083dbd9@syzkaller.appspotmail.com
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:19 -07:00
Andy Shevchenko
0684e6526e mm/slub.c: switch to bitmap_zalloc()
Switch to bitmap_zalloc() to show clearly what we are allocating.  Besides
that it returns pointer of bitmap type instead of opaque void *.

Link: http://lkml.kernel.org/r/20180830104301.61649-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:25:18 -07:00
Linus Torvalds
26873acacb Driver core patches for 4.20-rc1
Driver core patches for 4.20-rc1
 
 Here is a small number of driver core patches for 4.20-rc1.
 
 Not much happened here this merge window, only a very tiny number of
 patches that do:
 	- add BUS_ATTR_WO() for use by drivers
 	- component error path fixes
 	- kernfs range check fix
 	- other tiny error path fixes and const changes
 
 All of these have been in linux-next with no reported issues for a
 while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is a small number of driver core patches for 4.20-rc1.

  Not much happened here this merge window, only a very tiny number of
  patches that do:

   - add BUS_ATTR_WO() for use by drivers

   - component error path fixes

   - kernfs range check fix

   - other tiny error path fixes and const changes

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

* tag 'driver-core-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  devres: provide devm_kstrdup_const()
  mm: move is_kernel_rodata() to asm-generic/sections.h
  devres: constify p in devm_kfree()
  driver core: add BUS_ATTR_WO() macro
  kernfs: Fix range checks in kernfs_get_target_path
  component: fix loop condition to call unbind() if bind() fails
  drivers/base/devtmpfs.c: don't pretend path is const in delete_path
  kernfs: update comment about kernfs_path() return value
2018-10-26 08:42:25 -07:00
Wei Wang
d95f58f4a6 mm/page_poison: expose page_poisoning_enabled to kernel modules
In some usages, e.g. virtio-balloon, a kernel module needs to know if
page poisoning is in use. This patch exposes the page_poisoning_enabled
function to kernel modules.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-10-24 20:57:55 -04:00
Linus Torvalds
ba9f6f8954 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull siginfo updates from Eric Biederman:
 "I have been slowly sorting out siginfo and this is the culmination of
  that work.

  The primary result is in several ways the signal infrastructure has
  been made less error prone. The code has been updated so that manually
  specifying SEND_SIG_FORCED is never necessary. The conversion to the
  new siginfo sending functions is now complete, which makes it
  difficult to send a signal without filling in the proper siginfo
  fields.

  At the tail end of the patchset comes the optimization of decreasing
  the size of struct siginfo in the kernel from 128 bytes to about 48
  bytes on 64bit. The fundamental observation that enables this is by
  definition none of the known ways to use struct siginfo uses the extra
  bytes.

  This comes at the cost of a small user space observable difference.
  For the rare case of siginfo being injected into the kernel only what
  can be copied into kernel_siginfo is delivered to the destination, the
  rest of the bytes are set to 0. For cases where the signal and the
  si_code are known this is safe, because we know those bytes are not
  used. For cases where the signal and si_code combination is unknown
  the bits that won't fit into struct kernel_siginfo are tested to
  verify they are zero, and the send fails if they are not.

  I made an extensive search through userspace code and I could not find
  anything that would break because of the above change. If it turns out
  I did break something it will take just the revert of a single change
  to restore kernel_siginfo to the same size as userspace siginfo.

  Testing did reveal dependencies on preferring the signo passed to
  sigqueueinfo over si->signo, so bit the bullet and added the
  complexity necessary to handle that case.

  Testing also revealed bad things can happen if a negative signal
  number is passed into the system calls. Something no sane application
  will do but something a malicious program or a fuzzer might do. So I
  have fixed the code that performs the bounds checks to ensure negative
  signal numbers are handled"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (80 commits)
  signal: Guard against negative signal numbers in copy_siginfo_from_user32
  signal: Guard against negative signal numbers in copy_siginfo_from_user
  signal: In sigqueueinfo prefer sig not si_signo
  signal: Use a smaller struct siginfo in the kernel
  signal: Distinguish between kernel_siginfo and siginfo
  signal: Introduce copy_siginfo_from_user and use it's return value
  signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE
  signal: Fail sigqueueinfo if si_signo != sig
  signal/sparc: Move EMT_TAGOVF into the generic siginfo.h
  signal/unicore32: Use force_sig_fault where appropriate
  signal/unicore32: Generate siginfo in ucs32_notify_die
  signal/unicore32: Use send_sig_fault where appropriate
  signal/arc: Use force_sig_fault where appropriate
  signal/arc: Push siginfo generation into unhandled_exception
  signal/ia64: Use force_sig_fault where appropriate
  signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn
  signal/ia64: Use the generic force_sigsegv in setup_frame
  signal/arm/kvm: Use send_sig_mceerr
  signal/arm: Use send_sig_fault where appropriate
  signal/arm: Use force_sig_fault where appropriate
  ...
2018-10-24 11:22:39 +01:00
David Howells
aa563d7bca iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
David Howells
00e2370744 iov_iter: Use accessor function
Use accessor functions to access an iterator's type and direction.  This
allows for the possibility of using some other method of determining the
type of iterator than if-chains with bitwise-AND conditions.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:40:44 +01:00
Linus Torvalds
99792e0cea Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "Lots of changes in this cycle:

   - Lots of CPA (change page attribute) optimizations and related
     cleanups (Thomas Gleixner, Peter Zijstra)

   - Make lazy TLB mode even lazier (Rik van Riel)

   - Fault handler cleanups and improvements (Dave Hansen)

   - kdump, vmcore: Enable kdumping encrypted memory with AMD SME
     enabled (Lianbo Jiang)

   - Clean up VM layout documentation (Baoquan He, Ingo Molnar)

   - ... plus misc other fixes and enhancements"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  x86/stackprotector: Remove the call to boot_init_stack_canary() from cpu_startup_entry()
  x86/mm: Kill stray kernel fault handling comment
  x86/mm: Do not warn about PCI BIOS W+X mappings
  resource: Clean it up a bit
  resource: Fix find_next_iomem_res() iteration issue
  resource: Include resource end in walk_*() interfaces
  x86/kexec: Correct KEXEC_BACKUP_SRC_END off-by-one error
  x86/mm: Remove spurious fault pkey check
  x86/mm/vsyscall: Consider vsyscall page part of user address space
  x86/mm: Add vsyscall address helper
  x86/mm: Fix exception table comments
  x86/mm: Add clarifying comments for user addr space
  x86/mm: Break out user address space handling
  x86/mm: Break out kernel address space handling
  x86/mm: Clarify hardware vs. software "error_code"
  x86/mm/tlb: Make lazy TLB mode lazier
  x86/mm/tlb: Add freed_tables element to flush_tlb_info
  x86/mm/tlb: Add freed_tables argument to flush_tlb_mm_range
  smp,cpumask: introduce on_each_cpu_cond_mask
  smp: use __cpumask_set_cpu in on_each_cpu_cond
  ...
2018-10-23 17:05:28 +01:00
Linus Torvalds
0200fbdd43 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking and misc x86 updates from Ingo Molnar:
 "Lots of changes in this cycle - in part because locking/core attracted
  a number of related x86 low level work which was easier to handle in a
  single tree:

   - Linux Kernel Memory Consistency Model updates (Alan Stern, Paul E.
     McKenney, Andrea Parri)

   - lockdep scalability improvements and micro-optimizations (Waiman
     Long)

   - rwsem improvements (Waiman Long)

   - spinlock micro-optimization (Matthew Wilcox)

   - qspinlocks: Provide a liveness guarantee (more fairness) on x86.
     (Peter Zijlstra)

   - Add support for relative references in jump tables on arm64, x86
     and s390 to optimize jump labels (Ard Biesheuvel, Heiko Carstens)

   - Be a lot less permissive on weird (kernel address) uaccess faults
     on x86: BUG() when uaccess helpers fault on kernel addresses (Jann
     Horn)

   - macrofy x86 asm statements to un-confuse the GCC inliner. (Nadav
     Amit)

   - ... and a handful of other smaller changes as well"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
  locking/lockdep: Make global debug_locks* variables read-mostly
  locking/lockdep: Fix debug_locks off performance problem
  locking/pvqspinlock: Extend node size when pvqspinlock is configured
  locking/qspinlock_stat: Count instances of nested lock slowpaths
  locking/qspinlock, x86: Provide liveness guarantee
  x86/asm: 'Simplify' GEN_*_RMWcc() macros
  locking/qspinlock: Rework some comments
  locking/qspinlock: Re-order code
  locking/lockdep: Remove duplicated 'lock_class_ops' percpu array
  x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y
  futex: Replace spin_is_locked() with lockdep
  locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y
  x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs
  x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs
  x86/extable: Macrofy inline assembly code to work around GCC inlining bugs
  x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops
  x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs
  x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs
  x86/refcount: Work around GCC inlining bug
  x86/objtool: Use asm macros to work around GCC inlining bugs
  ...
2018-10-23 13:08:53 +01:00
Linus Torvalds
6ab9e09238 for-4.20/block-20181021
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Merge tag 'for-4.20/block-20181021' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:
 "This is the main pull request for block changes for 4.20. This
  contains:

   - Series enabling runtime PM for blk-mq (Bart).

   - Two pull requests from Christoph for NVMe, with items such as;
      - Better AEN tracking
      - Multipath improvements
      - RDMA fixes
      - Rework of FC for target removal
      - Fixes for issues identified by static checkers
      - Fabric cleanups, as prep for TCP transport
      - Various cleanups and bug fixes

   - Block merging cleanups (Christoph)

   - Conversion of drivers to generic DMA mapping API (Christoph)

   - Series fixing ref count issues with blkcg (Dennis)

   - Series improving BFQ heuristics (Paolo, et al)

   - Series improving heuristics for the Kyber IO scheduler (Omar)

   - Removal of dangerous bio_rewind_iter() API (Ming)

   - Apply single queue IPI redirection logic to blk-mq (Ming)

   - Set of fixes and improvements for bcache (Coly et al)

   - Series closing a hotplug race with sysfs group attributes (Hannes)

   - Set of patches for lightnvm:
      - pblk trace support (Hans)
      - SPDX license header update (Javier)
      - Tons of refactoring patches to cleanly abstract the 1.2 and 2.0
        specs behind a common core interface. (Javier, Matias)
      - Enable pblk to use a common interface to retrieve chunk metadata
        (Matias)
      - Bug fixes (Various)

   - Set of fixes and updates to the blk IO latency target (Josef)

   - blk-mq queue number updates fixes (Jianchao)

   - Convert a bunch of drivers from the old legacy IO interface to
     blk-mq. This will conclude with the removal of the legacy IO
     interface itself in 4.21, with the rest of the drivers (me, Omar)

   - Removal of the DAC960 driver. The SCSI tree will introduce two
     replacement drivers for this (Hannes)"

* tag 'for-4.20/block-20181021' of git://git.kernel.dk/linux-block: (204 commits)
  block: setup bounce bio_sets properly
  blkcg: reassociate bios when make_request() is called recursively
  blkcg: fix edge case for blk_get_rl() under memory pressure
  nvme-fabrics: move controller options matching to fabrics
  nvme-rdma: always have a valid trsvcid
  mtip32xx: fully switch to the generic DMA API
  rsxx: switch to the generic DMA API
  umem: switch to the generic DMA API
  sx8: switch to the generic DMA API
  sx8: remove dead IF_64BIT_DMA_IS_POSSIBLE code
  skd: switch to the generic DMA API
  ubd: remove use of blk_rq_map_sg
  nvme-pci: remove duplicate check
  drivers/block: Remove DAC960 driver
  nvme-pci: fix hot removal during error handling
  nvmet-fcloop: suppress a compiler warning
  nvme-core: make implicit seed truncation explicit
  nvmet-fc: fix kernel-doc headers
  nvme-fc: rework the request initialization code
  nvme-fc: introduce struct nvme_fcp_op_w_sgl
  ...
2018-10-22 17:46:08 +01:00
Linus Torvalds
5289851171 arm64 updates for 4.20:
- Core mmu_gather changes which allow tracking the levels of page-table
   being cleared together with the arm64 low-level flushing routines
 
 - Support for the new ARMv8.5 PSTATE.SSBS bit which can be used to
   mitigate Spectre-v4 dynamically without trapping to EL3 firmware
 
 - Introduce COMPAT_SIGMINSTKSZ for use in compat_sys_sigaltstack
 
 - Optimise emulation of MRS instructions to ID_* registers on ARMv8.4
 
 - Support for Common Not Private (CnP) translations allowing threads of
   the same CPU to share the TLB entries
 
 - Accelerated crc32 routines
 
 - Move swapper_pg_dir to the rodata section
 
 - Trap WFI instruction executed in user space
 
 - ARM erratum 1188874 workaround (arch_timer)
 
 - Miscellaneous fixes and clean-ups
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "Apart from some new arm64 features and clean-ups, this also contains
  the core mmu_gather changes for tracking the levels of the page table
  being cleared and a minor update to the generic
  compat_sys_sigaltstack() introducing COMPAT_SIGMINSKSZ.

  Summary:

   - Core mmu_gather changes which allow tracking the levels of
     page-table being cleared together with the arm64 low-level flushing
     routines

   - Support for the new ARMv8.5 PSTATE.SSBS bit which can be used to
     mitigate Spectre-v4 dynamically without trapping to EL3 firmware

   - Introduce COMPAT_SIGMINSTKSZ for use in compat_sys_sigaltstack

   - Optimise emulation of MRS instructions to ID_* registers on ARMv8.4

   - Support for Common Not Private (CnP) translations allowing threads
     of the same CPU to share the TLB entries

   - Accelerated crc32 routines

   - Move swapper_pg_dir to the rodata section

   - Trap WFI instruction executed in user space

   - ARM erratum 1188874 workaround (arch_timer)

   - Miscellaneous fixes and clean-ups"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (78 commits)
  arm64: KVM: Guests can skip __install_bp_hardening_cb()s HYP work
  arm64: cpufeature: Trap CTR_EL0 access only where it is necessary
  arm64: cpufeature: Fix handling of CTR_EL0.IDC field
  arm64: cpufeature: ctr: Fix cpu capability check for late CPUs
  Documentation/arm64: HugeTLB page implementation
  arm64: mm: Use __pa_symbol() for set_swapper_pgd()
  arm64: Add silicon-errata.txt entry for ARM erratum 1188873
  Revert "arm64: uaccess: implement unsafe accessors"
  arm64: mm: Drop the unused cpu parameter
  MAINTAINERS: fix bad sdei paths
  arm64: mm: Use #ifdef for the __PAGETABLE_P?D_FOLDED defines
  arm64: Fix typo in a comment in arch/arm64/mm/kasan_init.c
  arm64: xen: Use existing helper to check interrupt status
  arm64: Use daifflag_restore after bp_hardening
  arm64: daifflags: Use irqflags functions for daifflags
  arm64: arch_timer: avoid unused function warning
  arm64: Trap WFI executed in userspace
  arm64: docs: Document SSBS HWCAP
  arm64: docs: Fix typos in ELF hwcaps
  arm64/kprobes: remove an extra semicolon in arch_prepare_kprobe
  ...
2018-10-22 17:30:06 +01:00
Matthew Wilcox
3a08cd52c3 radix tree: Remove multiorder support
All users have now been converted to the XArray.  Removing the support
reduces code size and ensures new users will use the XArray instead.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:48 -04:00
Matthew Wilcox
a283348629 page cache: Finish XArray conversion
With no more radix tree API users left, we can drop the GFP flags
and use xa_init() instead of INIT_RADIX_TREE().

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:44 -04:00
Matthew Wilcox
7f4446eefe shmem: Comment fixups
Remove the last mentions of radix tree from various comments.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:41 -04:00
Matthew Wilcox
ef3038a573 memfd: Convert memfd_tag_pins to XArray
Switch to a batch-processing model like memfd_wait_for_pins() and
use the xa_state previously set up by memfd_wait_for_pins().

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
2018-10-21 10:46:41 -04:00
Matthew Wilcox
2313216f86 memfd: Convert memfd_wait_for_pins to XArray
Simplify the locking by taking the spinlock while we walk the tree on
the assumption that many acquires and releases of the lock will be worse
than holding the lock while we process an entire batch of pages.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
2018-10-21 10:46:40 -04:00
Matthew Wilcox
7ae3424fb4 shmem: Convert shmem_partial_swap_usage to XArray
Simpler code because the xarray takes care of things like the limit and
dereferencing the slot.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:40 -04:00
Matthew Wilcox
c121d3bb71 shmem: Convert shmem_free_swap to XArray
Since we are conditionally storing NULL in the XArray, we do not need
to allocate memory and the GFP flags will be unused.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:40 -04:00
Matthew Wilcox
7b8d046fba shmem: Convert shmem_alloc_hugepage to XArray
xa_find() is a slightly easier API to use than
radix_tree_gang_lookup_slot() because it contains its own RCU locking.
This commit removes the last user of radix_tree_gang_lookup_slot()
so remove the function too.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:40 -04:00
Matthew Wilcox
552446a416 shmem: Convert shmem_add_to_page_cache to XArray
We can use xas_find_conflict() instead of radix_tree_gang_lookup_slot()
to find any conflicting entry and combine the three paths through this
function into one.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:40 -04:00
Matthew Wilcox
e21a29552f shmem: Convert find_swap_entry to XArray
This is a 1:1 conversion.  The major part of this patch is converting
the test framework from userspace to kernel space and mirroring the
algorithm now used in find_swap_entry().

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:39 -04:00
Matthew Wilcox
a12831bf42 shmem: Convert shmem_confirm_swap to XArray
xa_load has its own RCU locking, so we can eliminate it here.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:39 -04:00
Matthew Wilcox
62f945b6a7 shmem: Convert shmem_radix_tree_replace to XArray
Rename shmem_radix_tree_replace() to shmem_replace_entry() and
convert it to use the XArray API.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:39 -04:00
Matthew Wilcox
10bbd23585 pagevec: Use xa_mark_t
Removes sparse warnings.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:39 -04:00
Matthew Wilcox
67891ffff2 mm: Convert is_page_cache_freeable to XArray
This is just a variable rename and comment change.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:38 -04:00
Matthew Wilcox
85b392dbac mm: Convert khugepaged_scan_shmem to XArray
Slightly shorter and easier to read code.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:38 -04:00
Matthew Wilcox
77da9389b9 mm: Convert collapse_shmem to XArray
I found another victim of the radix tree being hard to use.  Because
there was no call to radix_tree_preload(), khugepaged was allocating
radix_tree_nodes using GFP_ATOMIC.

I also converted a local_irq_save()/restore() pair to
disable()/enable().

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:38 -04:00
Matthew Wilcox
aa5dc07f70 mm: Convert huge_memory to XArray
Quite a straightforward conversion.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:38 -04:00
Matthew Wilcox
89eb946a74 mm: Convert page migration to XArray
Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:38 -04:00
Matthew Wilcox
560d454bae mm: Convert __do_page_cache_readahead to XArray
This one is trivial.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:37 -04:00
Matthew Wilcox
4e17ec250f mm: Convert delete_from_swap_cache to XArray
Both callers of __delete_from_swap_cache have the swp_entry_t already,
so pass that in to make constructing the XA_STATE easier.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:37 -04:00
Matthew Wilcox
8d93b41c09 mm: Convert add_to_swap_cache to XArray
Combine __add_to_swap_cache and add_to_swap_cache into one function
since there is no more need to preload.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:37 -04:00
Matthew Wilcox
69b6c1319b mm: Convert truncate to XArray
This is essentially xa_cmpxchg() with the locking handled above us,
and it doesn't have to handle replacing a NULL entry.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:37 -04:00
Matthew Wilcox
a97e7904c0 mm: Convert workingset to XArray
We construct an XA_STATE and use it to delete the node with
xas_store() rather than adding a special function for this unique
use case.  Includes a test that simulates this usage for the
test suite.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:36 -04:00
Matthew Wilcox
ff9c745b81 mm: Convert page-writeback to XArray
Includes moving mapping_tagged() to fs.h as a static inline, and
changing it to return bool.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:36 -04:00
Matthew Wilcox
8fa8e538e4 page cache: Convert filemap_range_has_page to XArray
Instead of calling find_get_pages_range() and putting any reference,
use xas_find() to iterate over any entries in the range, skipping the
shadow/swap entries.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:36 -04:00
Matthew Wilcox
22ecdb4f8b page cache: Remove stray radix comment
Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:36 -04:00
Matthew Wilcox
ef8e5717db page cache: Convert delete_batch to XArray
Rename the function from page_cache_tree_delete_batch to just
page_cache_delete_batch.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:36 -04:00
Matthew Wilcox
070e807c69 page cache: Convert filemap_map_pages to XArray
Slight change of strategy here; if we have trouble getting hold of a
page for whatever reason (eg a compound page is split underneath us),
don't spin to stabilise the page, just continue the iteration, like we
would if we failed to trylock the page.  Since this is a speculative
optimisation, it feels like we should allow the process to take an extra
fault if it turns out to need this page instead of spending time to pin
down a page it may not need.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:35 -04:00
Matthew Wilcox
c1901cd33c page cache: Convert find_get_entries_tag to XArray
Slightly shorter and simpler code.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21 10:46:35 -04:00