maple_tree: make the code symmetrical in mas_wr_extend_null()

Just make the code symmetrical to improve readability.

Link: https://lkml.kernel.org/r/20230524031247.65949-6-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: simplify mas_is_span_wr()

Make the code for detecting spanning writes more concise.

Link: https://lkml.kernel.org/r/20230524031247.65949-5-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: fix the arguments to __must_hold()

Fix the arguments to __must_hold() to make sparse work.

Link: https://lkml.kernel.org/r/20230524031247.65949-4-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: drop mas_{rev_}alloc() and mas_fill_gap()

mas_{rev_}alloc() and mas_fill_gap() are no longer used, delete them.

Link: https://lkml.kernel.org/r/20230524031247.65949-3-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: rework mtree_alloc_{range,rrange}()

Patch series "Clean ups for maple tree", v4.

Some clean ups, mainly to make the code of maple tree more concise.
This patchset has passed the self-test.

This patch (of 10):

Use mas_empty_area{_rev}() to refactor mtree_alloc_{range,rrange}()

Link: https://lkml.kernel.org/r/20230524031247.65949-2-zhangpeng.00@bytedance.com
Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/memcontrol: export memcg.swap watermark via sysfs for v2 memcg

This patch is similar to commit 8e20d4b33266 ("mm/memcontrol: export
memcg->watermark via sysfs for v2 memcg"), but exports the swap counter's
watermark.

We allocate jobs to our compute farm using heuristics determined by memory
and swap usage from previous jobs.  Tracking the peak swap usage for new
jobs is important for determining when jobs are exceeding their expected
bounds, or when our baseline metrics are getting outdated.

Our toolset was written to use the "memory.memsw.max_usage_in_bytes" file
in cgroups v1, and altering it to poll cgroups v2's "memory.swap.current"
would give less accurate results as well as add complication to the code.
Having this watermark exposed in sysfs is much preferred.

Link: https://lkml.kernel.org/r/20230524181734.125696-1-lars@pixar.com
Signed-off-by: Lars R. Damerow <lars@pixar.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: shmem: fix UAF bug in shmem_show_options()

shmem_show_options() uses sbinfo->mpol without adding it's refcnt. This
may lead to race with replacement of the mpol by remount. The execution
sequence is as follows.

       CPU0                                   CPU1
shmem_show_options()                        shmem_reconfigure()
    shmem_show_mpol(seq, sbinfo->mpol)          mpol = sbinfo->mpol
                                                mpol_put(mpol)
        mpol->mode

The KASAN report is as follows.

BUG: KASAN: slab-use-after-free in shmem_show_options+0x21b/0x340
Read of size 2 at addr ffff888124324004 by task mount/2388

CPU: 2 PID: 2388 Comm: mount Not tainted 6.4.0-rc3-00017-g9d646009f65d-dirty #8
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x37/0x50
 print_report+0xd0/0x620
 ? shmem_show_options+0x21b/0x340
 ? __virt_addr_valid+0xf4/0x180
 ? shmem_show_options+0x21b/0x340
 kasan_report+0xb8/0xe0
 ? shmem_show_options+0x21b/0x340
 shmem_show_options+0x21b/0x340
 ? __pfx_shmem_show_options+0x10/0x10
 ? strchr+0x2c/0x50
 ? strlen+0x23/0x40
 ? seq_puts+0x7d/0x90
 show_vfsmnt+0x1e6/0x260
 ? __pfx_show_vfsmnt+0x10/0x10
 ? __kasan_kmalloc+0x7f/0x90
 seq_read_iter+0x57a/0x740
 vfs_read+0x2e2/0x4a0
 ? __pfx_vfs_read+0x10/0x10
 ? down_write_killable+0xb8/0x140
 ? __pfx_down_write_killable+0x10/0x10
 ? __fget_light+0xa9/0x1e0
 ? up_write+0x3f/0x80
 ksys_read+0xb8/0x150
 ? __pfx_ksys_read+0x10/0x10
 ? fpregs_assert_state_consistent+0x55/0x60
 ? exit_to_user_mode_prepare+0x2d/0x120
 do_syscall_64+0x3c/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

 </TASK>

Allocated by task 2387:
 kasan_save_stack+0x22/0x50
 kasan_set_track+0x25/0x30
 __kasan_slab_alloc+0x59/0x70
 kmem_cache_alloc+0xdd/0x220
 mpol_new+0x83/0x150
 mpol_parse_str+0x280/0x4a0
 shmem_parse_one+0x364/0x520
 vfs_parse_fs_param+0xf8/0x1a0
 vfs_parse_fs_string+0xc9/0x130
 shmem_parse_options+0xb2/0x110
 path_mount+0x597/0xdf0
 do_mount+0xcd/0xf0
 __x64_sys_mount+0xbd/0x100
 do_syscall_64+0x3c/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

Freed by task 2389:
 kasan_save_stack+0x22/0x50
 kasan_set_track+0x25/0x30
 kasan_save_free_info+0x2e/0x50
 __kasan_slab_free+0x10e/0x1a0
 kmem_cache_free+0x9c/0x350
 shmem_reconfigure+0x278/0x370
 reconfigure_super+0x383/0x450
 path_mount+0xcc5/0xdf0
 do_mount+0xcd/0xf0
 __x64_sys_mount+0xbd/0x100
 do_syscall_64+0x3c/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

The buggy address belongs to the object at ffff888124324000
 which belongs to the cache numa_policy of size 32
The buggy address is located 4 bytes inside of
 freed 32-byte region [ffff888124324000, ffff888124324020)
==================================================================

To fix the bug, shmem_get_sbmpol() / mpol_put() needs to be called
before / after shmem_show_mpol() call.

Link: https://lkml.kernel.org/r/20230525031640.593733-1-tujinjiang@huawei.com
Signed-off-by: Tu Jinjiang <tujinjiang@huawei.com>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: skip fast freepages isolation if enough freepages are isolated

I've observed that fast isolation often isolates more pages than
cc->migratepages, and the excess freepages will be released back to the
buddy system.  So skip fast freepages isolation if enough freepages are
isolated to save some CPU cycles.

Link: https://lkml.kernel.org/r/f39c2c07f2dba2732fd9c0843572e5bef96f7f67.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: add trace event for fast freepages isolation

The fast_isolate_freepages() can also isolate freepages, but we can not
know the fast isolation efficiency to understand the fast isolation
pressure.  So add a trace event to show some numbers to help to understand
the efficiency for fast freepages isolation.

Link: https://lkml.kernel.org/r/78d2932d0160d122c15372aceb3f2c45460a17fc.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: only set skip flag if cc->no_set_skip_hint is false

To keep the same logic as test_and_set_skip(), only set the skip flag if
cc->no_set_skip_hint is false, which makes code more reasonable.

Link: https://lkml.kernel.org/r/0eb2cd2407ffb259ae6e3071e10f70f2d41d0f3e.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: skip more fully scanned pageblock

In fast_isolate_around(), it assumes the pageblock is fully scanned if
cc->nr_freepages < cc->nr_migratepages after trying to isolate some free
pages, and will set skip flag to avoid scanning in future.  However this
can miss setting the skip flag for a fully scanned pageblock (returned
'start_pfn' is equal to 'end_pfn') in the case where cc->nr_freepages is
larger than cc->nr_migratepages.

So using the returned 'start_pfn' from isolate_freepages_block() and
'end_pfn' to decide if a pageblock is fully scanned makes more sense.  It
can also cover the case where cc->nr_freepages < cc->nr_migratepages,
which means the 'start_pfn' is usually equal to 'end_pfn' except some
uncommon fatal error occurs after non-strict mode isolation.

Link: https://lkml.kernel.org/r/f4efd2fa08735794a6d809da3249b6715ba6ad38.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: change fast_isolate_freepages() to void type

No caller cares about the return value of fast_isolate_freepages(), void
it.

Link: https://lkml.kernel.org/r/759fca20b22ebf4c81afa30496837b9e0fb2e53b.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: drop the redundant page validation in update_pageblock_skip()

Patch series "Misc cleanups and improvements for compaction".

This series cantains some cleanups and improvements for compaction.

This patch (of 6):

The caller has validated the page before calling
update_pageblock_skip(), thus drop the redundant page validation in
update_pageblock_skip().

Link: https://lkml.kernel.org/r/5142e15b9295fe8c447dbb39b7907a20177a1413.1685018752.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmalloc: dont purge usable blocks unnecessarily

Purging fragmented blocks is done unconditionally in several contexts:

  1) From drain_vmap_area_work(), when the number of lazy to be freed
     vmap_areas reached the threshold

  2) Reclaiming vmalloc address space from pcpu_get_vm_areas()

  3) _vm_unmap_aliases()

#1 There is no reason to zap fragmented vmap blocks unconditionally, simply
   because reclaiming all lazy areas drains at least

      32MB * fls(num_online_cpus())

   per invocation which is plenty.

#2 Reclaiming when running out of space or due to memory pressure makes a
   lot of sense

#3 _unmap_aliases() requires to touch everything because the caller has no
   clue which vmap_area used a particular page last and the vmap_area lost
   that information too.

   Except for the vfree + VM_FLUSH_RESET_PERMS case, which removes the
   vmap area first and then cares about the flush. That in turn requires
   a full walk of _all_ vmap areas including the one which was just
   added to the purge list.

   But as this has to be flushed anyway this is an opportunity to combine
   outstanding TLB flushes and do the housekeeping of purging freed areas,
   but like #1 there is no real good reason to zap usable vmap blocks
   unconditionally.

Add a @force_purge argument to the newly split out block purge function and
if not true only purge fragmented blocks which have less than 1/4 of their
capacity left.

Rename purge_vmap_area_lazy() to reclaim_and_purge_vmap_areas() to make it
clear what the function does.

[lstoakes@gmail.com: correct VMAP_PURGE_THRESHOLD check]
Link: https://lkml.kernel.org/r/3e92ef61-b910-4576-88e7-cf43211fd4e7@lucifer.local
Link: https://lkml.kernel.org/r/20230525124504.864005691@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmalloc: add missing READ/WRITE_ONCE() annotations

purge_fragmented_blocks() accesses vmap_block::free and vmap_block::dirty
lockless for a quick check.

Add the missing READ/WRITE_ONCE() annotations.

Link: https://lkml.kernel.org/r/20230525124504.807356682@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmalloc: check free space in vmap_block lockless

vb_alloc() unconditionally locks a vmap_block on the free list to check
the free space.

This can be done locklessly because vmap_block::free never increases, it's
only decreased on allocations.

Check the free space lockless and only if that succeeds, recheck under the
lock.

Link: https://lkml.kernel.org/r/20230525124504.750481992@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmalloc: prevent flushing dirty space over and over

vmap blocks which have active mappings cannot be purged.  Allocations
which have been freed are accounted for in vmap_block::dirty_min/max, so
that they can be detected in _vm_unmap_aliases() as potentially stale
TLBs.

If there are several invocations of _vm_unmap_aliases() then each of them
will flush the dirty range.  That's pointless and just increases the
probability of full TLB flushes.

Avoid that by resetting the flush range after accounting for it.  That's
safe versus other invocations of _vm_unmap_aliases() because this is all
serialized with vmap_purge_lock.

Link: https://lkml.kernel.org/r/20230525124504.692056496@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmalloc: avoid iterating over per CPU vmap blocks twice

_vunmap_aliases() walks the per CPU xarrays to find partially unmapped
blocks and then walks the per cpu free lists to purge fragmented blocks.

Arguably that's waste of CPU cycles and cache lines as the full xarray
walk already touches every block.

Avoid this double iteration:

  - Split out the code to purge one block and the code to free the local
    purge list into helper functions.

  - Try to purge the fragmented blocks in the xarray walk before looking at
    their dirty space.

Link: https://lkml.kernel.org/r/20230525124504.633469722@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmalloc: prevent stale TLBs in fully utilized blocks

Patch series "mm/vmalloc: Assorted fixes and improvements", v2.

this series addresses the following issues:

  1) Prevent the stale TLB problem related to fully utilized vmap blocks

  2) Avoid the double per CPU list walk in _vm_unmap_aliases()

  3) Avoid flushing dirty space over and over

  4) Add a lockless quickcheck in vb_alloc() and add missing
     READ/WRITE_ONCE() annotations

  5) Prevent overeager purging of usable vmap_blocks if
     not under memory/address space pressure.

This patch (of 6):

_vm_unmap_aliases() is used to ensure that no unflushed TLB entries for a
page are left in the system. This is required due to the lazy TLB flush
mechanism in vmalloc.

This is tried to achieve by walking the per CPU free lists, but those do
not contain fully utilized vmap blocks because they are removed from the
free list once the blocks free space became zero.

When the block is not fully unmapped then it is not on the purge list
either.

So neither the per CPU list iteration nor the purge list walk find the
block and if the page was mapped via such a block and the TLB has not yet
been flushed, the guarantee of _vm_unmap_aliases() that there are no stale
TLBs after returning is broken:

x = vb_alloc() // Removes vmap_block from free list because vb->free became 0
vb_free(x)     // Unmaps page and marks in dirty_min/max range
       // Block has still mappings and is not put on purge list

// Page is reused
vm_unmap_aliases() // Can't find vmap block with the dirty space -> FAIL

So instead of walking the per CPU free lists, walk the per CPU xarrays
which hold pointers to _all_ active blocks in the system including those
removed from the free lists.

Link: https://lkml.kernel.org/r/20230525122342.109672430@linutronix.de
Link: https://lkml.kernel.org/r/20230525124504.573987880@linutronix.de
Fixes: db64fe02258f ("mm: rewrite vmap layer")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kmemleak-test: drop __init to get better backtrace

Drop the __init on kmemleak_test_init().  With it, the storage is
reclaimed, but then the symbol isn't available for "%pS" rendering,
and the backtrace gets a bare pointer where the actual leak happened.

unreferenced object 0xffff88800a2b0800 (size 1024):
  comm "modprobe", pid 413, jiffies 4294953430
  hex dump (first 32 bytes):
    73 02 00 00 75 01 00 68 02 00 00 01 00 00 00 04  s...u..h........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000fabad728>] kmalloc_trace+0x26/0x90
    [<00000000ef738764>] 0xffffffffc02350a2
    [<00000000004e5795>] do_one_initcall+0x43/0x210
    [<00000000d768905e>] do_init_module+0x4a/0x210
    [<0000000087135ab5>] __do_sys_finit_module+0x93/0xf0
    [<000000004fcb1fa2>] do_syscall_64+0x34/0x80
    [<00000000c73c8d9d>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

with __init gone, that trace entry renders like:

    [<00000000ef738764>] kmemleak_test_init+<offset>/<size>

Link: https://lkml.kernel.org/r/20230525174356.69711-1-jim.cromie@gmail.com
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: multi-gen LRU: cleanup lru_gen_test_recent()

Avoid passing memcg* and pglist_data* to lru_gen_test_recent()
since we only use the lruvec anyway.

Link: https://lkml.kernel.org/r/20230522112058.2965866-4-talumbau@google.com
Signed-off-by: T.J. Alumbaugh <talumbau@google.com>
Reviewed-by: Yuanchu Xie <yuanchu@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: multi-gen LRU: add helpers in page table walks

Add helpers to page table walking code:
 - Clarifies intent via name "should_walk_mmu" and "should_clear_pmd_young"
 - Avoids repeating same logic in two places

Link: https://lkml.kernel.org/r/20230522112058.2965866-3-talumbau@google.com
Signed-off-by: T.J. Alumbaugh <talumbau@google.com>
Reviewed-by: Yuanchu Xie <yuanchu@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: multi-gen LRU: cleanup lru_gen_soft_reclaim()

lru_gen_soft_reclaim() gets the lruvec from the memcg and node ID to keep a
cleaner interface on the caller side.

Link: https://lkml.kernel.org/r/20230522112058.2965866-2-talumbau@google.com
Signed-off-by: T.J. Alumbaugh <talumbau@google.com>
Reviewed-by: Yuanchu Xie <yuanchu@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: multi-gen LRU: use macro for bitmap

Use DECLARE_BITMAP macro when possible.

Link: https://lkml.kernel.org/r/20230522112058.2965866-1-talumbau@google.com
Signed-off-by: T.J. Alumbaugh <talumbau@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yuanchu Xie <yuanchu@google.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

selftests: cgroup: fix unexpected failure on test_memcg_low

Since commit f079a020ba95 ("selftests: memcg: factor out common parts of
memory.{low,min} tests"), the value used in second alloc_anon has changed
from 148M to 170M.  Because memory.low allows reclaiming page cache in
child cgroups, so the memory.current is close to 30M instead of 50M.
Therefore, adjust the expected value of parent cgroup.

Link: https://lkml.kernel.org/r/20230522095233.4246-2-haifeng.xu@shopee.com
Fixes: f079a020ba95 ("selftests: memcg: factor out common parts of memory.{low,min} tests")
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/memcontrol: fix typo in comment

Replace 'then' with 'than'.

Link: https://lkml.kernel.org/r/20230522095233.4246-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/mlock: rename mlock_future_check() to mlock_future_ok()

It is felt that the name mlock_future_check() is vague - it doesn't
particularly convey the function's operation.  mlock_future_ok() is a
clearer name for a predicate function.

Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/mmap: refactor mlock_future_check()

In all but one instance, mlock_future_check() is treated as a boolean
function despite returning an error code.  In one instance, this error
code is ignored and replaced with -ENOMEM.

This is confusing, and the inversion of true -> failure, false -> success
is not warranted.  Convert the function to a bool, lightly refactor and
return true if the check passes, false if not.

Link: https://lkml.kernel.org/r/20230522082412.56685-1-lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

selftests/mm: gup_longterm: add liburing tests

Similar to the COW selftests, also use io_uring fixed buffers to test if
long-term page pinning works as expected.

Link: https://lkml.kernel.org/r/20230519102723.185721-4-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

selftests/mm: gup_longterm: new functional test for FOLL_LONGTERM

Let's add a new test for checking whether GUP long-term page pinning works
as expected (R/O vs.  R/W, MAP_PRIVATE vs.  MAP_SHARED, GUP vs.
GUP-fast).  Note that COW handling with long-term R/O pinning in private
mappings, and pinning of anonymous memory in general, is tested by the COW
selftest.  This test, therefore, focuses on page pinning in file mappings.

The most interesting case is probably the "local tmpfile" case, as that
will likely end up on a "real" filesystem such as ext4 or xfs, not on a
virtual one like tmpfs or hugetlb where any long-term page pinning is
always expected to succeed.

For now, only add tests that use the "/sys/kernel/debug/gup_test"
interface.  We'll add tests based on liburing separately next.

[akpm@linux-foundation.org: update .gitignore for gup_longterm, per Peter]
Link: https://lkml.kernel.org/r/20230519102723.185721-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

selftests/mm: factor out detection of hugetlb page sizes into vm_util

Patch series "selftests/mm: new test for FOLL_LONGTERM on file mappings".

Let's add some selftests to make sure that:
* R/O long-term pinning always works of file mappings
* R/W long-term pinning always works in MAP_PRIVATE file mappings
* R/W long-term pinning only works in MAP_SHARED mappings with special
  filesystems (shmem, hugetlb) and fails with other filesystems (ext4, btrfs,
  xfs).

The tests make use of the gup_test kernel module to trigger ordinary GUP
and GUP-fast, and liburing (similar to our COW selftests).  Test with
memfd, memfd hugetlb, tmpfile() and mkstemp().  The latter usually gives
us a "real" filesystem (ext4, btrfs, xfs) where long-term pinning is
expected to fail.

Note that these selftests don't contain any actual reproducers for data
corruptions in case R/W long-term pinning on problematic filesystems
"would" work.

Maybe we can later come up with a racy !FOLL_LONGTERM reproducer that can
reuse an existing interface to trigger short-term pinning (I'll look into
that next).

On current mm/mm-unstable:
# ./gup_longterm
# [INFO] detected hugetlb page size: 2048 KiB
# [INFO] detected hugetlb page size: 1048576 KiB
TAP version 13
1..50
# [RUN] R/W longterm GUP pin in MAP_SHARED file mapping ... with memfd
ok 1 Should have worked
# [RUN] R/W longterm GUP pin in MAP_SHARED file mapping ... with tmpfile
ok 2 Should have worked
# [RUN] R/W longterm GUP pin in MAP_SHARED file mapping ... with local tmpfile
ok 3 Should have failed
# [RUN] R/W longterm GUP pin in MAP_SHARED file mapping ... with memfd hugetlb (2048 kB)
ok 4 Should have worked
# [RUN] R/W longterm GUP pin in MAP_SHARED file mapping ... with memfd hugetlb (1048576 kB)
ok 5 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_SHARED file mapping ... with memfd
ok 6 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_SHARED file mapping ... with tmpfile
ok 7 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_SHARED file mapping ... with local tmpfile
ok 8 Should have failed
# [RUN] R/W longterm GUP-fast pin in MAP_SHARED file mapping ... with memfd hugetlb (2048 kB)
ok 9 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_SHARED file mapping ... with memfd hugetlb (1048576 kB)
ok 10 Should have worked
# [RUN] R/O longterm GUP pin in MAP_SHARED file mapping ... with memfd
ok 11 Should have worked
# [RUN] R/O longterm GUP pin in MAP_SHARED file mapping ... with tmpfile
ok 12 Should have worked
# [RUN] R/O longterm GUP pin in MAP_SHARED file mapping ... with local tmpfile
ok 13 Should have worked
# [RUN] R/O longterm GUP pin in MAP_SHARED file mapping ... with memfd hugetlb (2048 kB)
ok 14 Should have worked
# [RUN] R/O longterm GUP pin in MAP_SHARED file mapping ... with memfd hugetlb (1048576 kB)
ok 15 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_SHARED file mapping ... with memfd
ok 16 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_SHARED file mapping ... with tmpfile
ok 17 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_SHARED file mapping ... with local tmpfile
ok 18 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_SHARED file mapping ... with memfd hugetlb (2048 kB)
ok 19 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_SHARED file mapping ... with memfd hugetlb (1048576 kB)
ok 20 Should have worked
# [RUN] R/W longterm GUP pin in MAP_PRIVATE file mapping ... with memfd
ok 21 Should have worked
# [RUN] R/W longterm GUP pin in MAP_PRIVATE file mapping ... with tmpfile
ok 22 Should have worked
# [RUN] R/W longterm GUP pin in MAP_PRIVATE file mapping ... with local tmpfile
ok 23 Should have worked
# [RUN] R/W longterm GUP pin in MAP_PRIVATE file mapping ... with memfd hugetlb (2048 kB)
ok 24 Should have worked
# [RUN] R/W longterm GUP pin in MAP_PRIVATE file mapping ... with memfd hugetlb (1048576 kB)
ok 25 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_PRIVATE file mapping ... with memfd
ok 26 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_PRIVATE file mapping ... with tmpfile
ok 27 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_PRIVATE file mapping ... with local tmpfile
ok 28 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_PRIVATE file mapping ... with memfd hugetlb (2048 kB)
ok 29 Should have worked
# [RUN] R/W longterm GUP-fast pin in MAP_PRIVATE file mapping ... with memfd hugetlb (1048576 kB)
ok 30 Should have worked
# [RUN] R/O longterm GUP pin in MAP_PRIVATE file mapping ... with memfd
ok 31 Should have worked
# [RUN] R/O longterm GUP pin in MAP_PRIVATE file mapping ... with tmpfile
ok 32 Should have worked
# [RUN] R/O longterm GUP pin in MAP_PRIVATE file mapping ... with local tmpfile
ok 33 Should have worked
# [RUN] R/O longterm GUP pin in MAP_PRIVATE file mapping ... with memfd hugetlb (2048 kB)
ok 34 Should have worked
# [RUN] R/O longterm GUP pin in MAP_PRIVATE file mapping ... with memfd hugetlb (1048576 kB)
ok 35 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_PRIVATE file mapping ... with memfd
ok 36 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_PRIVATE file mapping ... with tmpfile
ok 37 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_PRIVATE file mapping ... with local tmpfile
ok 38 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_PRIVATE file mapping ... with memfd hugetlb (2048 kB)
ok 39 Should have worked
# [RUN] R/O longterm GUP-fast pin in MAP_PRIVATE file mapping ... with memfd hugetlb (1048576 kB)
ok 40 Should have worked
# [RUN] io_uring fixed buffer with MAP_SHARED file mapping ... with memfd
ok 41 Should have worked
# [RUN] io_uring fixed buffer with MAP_SHARED file mapping ... with tmpfile
ok 42 Should have worked
# [RUN] io_uring fixed buffer with MAP_SHARED file mapping ... with local tmpfile
ok 43 Should have failed
# [RUN] io_uring fixed buffer with MAP_SHARED file mapping ... with memfd hugetlb (2048 kB)
ok 44 Should have worked
# [RUN] io_uring fixed buffer with MAP_SHARED file mapping ... with memfd hugetlb (1048576 kB)
ok 45 Should have worked
# [RUN] io_uring fixed buffer with MAP_PRIVATE file mapping ... with memfd
ok 46 Should have worked
# [RUN] io_uring fixed buffer with MAP_PRIVATE file mapping ... with tmpfile
ok 47 Should have worked
# [RUN] io_uring fixed buffer with MAP_PRIVATE file mapping ... with local tmpfile
ok 48 Should have worked
# [RUN] io_uring fixed buffer with MAP_PRIVATE file mapping ... with memfd hugetlb (2048 kB)
ok 49 Should have worked
# [RUN] io_uring fixed buffer with MAP_PRIVATE file mapping ... with memfd hugetlb (1048576 kB)
ok 50 Should have worked
# Totals: pass:50 fail:0 xfail:0 xpass:0 skip:0 error:0

This patch (of 3):

Let's factor detection out into vm_util, to be reused by a new test.

Link: https://lkml.kernel.org/r/20230519102723.185721-1-david@redhat.com
Link: https://lkml.kernel.org/r/20230519102723.185721-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: avoid GFP_NOFS ABBA deadlock

During stress testing with higher-order allocations, a deadlock scenario
was observed in compaction: One GFP_NOFS allocation was sleeping on
mm/compaction.c::too_many_isolated(), while all CPUs in the system were
busy with compactors spinning on buffer locks held by the sleeping
GFP_NOFS allocation.

Reclaim is susceptible to this same deadlock; we fixed it by granting
GFP_NOFS allocations additional LRU isolation headroom, to ensure it makes
forward progress while holding fs locks that other reclaimers might
acquire.  Do the same here.

This code has been like this since compaction was initially merged, and I
only managed to trigger this with out-of-tree patches that dramatically
increase the contexts that do GFP_NOFS compaction.  While the issue is
real, it seems theoretical in nature given existing allocation sites.
Worth fixing now, but no Fixes tag or stable CC.

Link: https://lkml.kernel.org/r/20230519111359.40475-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: have compaction_suitable() return bool

Since it only returns COMPACT_CONTINUE or COMPACT_SKIPPED now, a bool
return value simplifies the callsites.

Link: https://lkml.kernel.org/r/20230602151204.GD161817@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: drop redundant watermark check in compaction_zonelist_suitable()

The watermark check in compaction_zonelist_suitable(), called from
should_compact_retry(), is sandwiched between two watermark checks
already: before, there are freelist attempts as part of direct reclaim and
direct compaction; after, there is a last-minute freelist attempt in
__alloc_pages_may_oom().

The check in compaction_zonelist_suitable() isn't necessary. Kill it.

Link: https://lkml.kernel.org/r/20230519123959.77335-6-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: remove unnecessary is_via_compact_memory() checks

Remove from all paths not reachable via /proc/sys/vm/compact_memory.

Link: https://lkml.kernel.org/r/20230519123959.77335-5-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: refactor __compaction_suitable()

__compaction_suitable() is supposed to check for available migration
targets.  However, it also checks whether the operation was requested via
/proc/sys/vm/compact_memory, and whether the original allocation request
can already succeed.  These don't apply to all callsites.

Move the checks out to the callers, so that later patches can deal with
them one by one.  No functional change intended.

[hannes@cmpxchg.org: fix comment, per Vlastimil]
Link: https://lkml.kernel.org/r/20230602144942.GC161817@cmpxchg.org
Link: https://lkml.kernel.org/r/20230519123959.77335-4-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: simplify should_compact_retry()

The different branches for retry are unnecessarily complicated.  There are
really only three outcomes: progress (retry n times), skipped (retry if
reclaim can help), failed (retry with higher priority).

Rearrange the branches and the retry counter to make it simpler.

[hannes@cmpxchg.org: restore behavior when hitting max_retries]
Link: https://lkml.kernel.org/r/20230602144705.GB161817@cmpxchg.org
Link: https://lkml.kernel.org/r/20230519123959.77335-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: remove compaction result helpers

Patch series "mm: compaction: cleanups & simplifications".

These compaction cleanups are split out from the huge page allocator
series[1], as requested by reviewer feedback.

[1] https://lore.kernel.org/linux-mm/20230418191313.268131-1-hannes@cmpxchg.org/

This patch (of 5):

The compaction result helpers encode quirks that are specific to the
allocator's retry logic.  E.g.  COMPACT_SUCCESS and COMPACT_COMPLETE
actually represent failures that should be retried upon, and so on.  I
frequently found myself pulling up the helper implementation in order to
understand and work on the retry logic.  They're not quite clean
abstractions; rather they split the retry logic into two locations.

Remove the helpers and inline the checks.  Then comment on the result
interpretations directly where the decision making happens.

Link: https://lkml.kernel.org/r/20230519123959.77335-1-hannes@cmpxchg.org
Link: https://lkml.kernel.org/r/20230519123959.77335-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: set sysctl_lowmem_reserve_ratio storage-class-specifier to static

smatch reports
mm/page_alloc.c:247:5: warning: symbol
  'sysctl_lowmem_reserve_ratio' was not declared. Should it be static?

This variable is only used in its defining file, so it should be static

Link: https://lkml.kernel.org/r/20230518141119.927074-1-trix@redhat.com
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: avoid rewalk in mmap_region

If the iterator has moved to the previous entry, then step forward one
range, back to the gap.

Link: https://lkml.kernel.org/r/20230518145544.1722059-36-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: add vma_iter_{next,prev}_range() to vma iterator

Add functionality to the VMA iterator to advance and retreat one offset
within the maple tree, regardless of the value contained.  This can lead
to less re-walking to find an area of interest, especially when there is
nothing in that offset.

Link: https://lkml.kernel.org/r/20230518145544.1722059-35-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: update testing code for mas_{next,prev,walk}

Now that the functions have changed the limits, update the testing of the
maple tree to test these new settings.

Link: https://lkml.kernel.org/r/20230518145544.1722059-34-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: clear up index and last setting in single entry tree

When there is a single entry tree (range of 0-0 pointing to an entry),
then ensure the limit is either 0-0 or 1-oo, depending on where the user
walks.  Ensure the correct node setting as well; either MAS_ROOT or
MAS_NONE.

Link: https://lkml.kernel.org/r/20230518145544.1722059-33-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: add mas_prev_range() and mas_find_range_rev interface

Some users of the maple tree may want to move to the previous range
regardless of the value stored there.  Add this interface as well as the
'find' variant to support walking to the first value, then iterating over
the previous ranges.

Link: https://lkml.kernel.org/r/20230518145544.1722059-32-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: introduce mas_prev_slot() interface

Sometimes the user needs to revert to the previous slot, regardless of if
it is empty or not.  Add an interface to go to the previous slot.

Since there can't be two consecutive NULLs in the tree, the mas_prev()
function can be implemented by calling mas_prev_slot() a maximum of 2
times.  Change the underlying interface to use mas_prev_slot() to align
the code.

Link: https://lkml.kernel.org/r/20230518145544.1722059-31-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: relocate mas_rewalk() and mas_rewalk_if_dead()

These functions need to move for future use.

Link: https://lkml.kernel.org/r/20230518145544.1722059-30-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: add mas_next_range() and mas_find_range() interfaces

Some users of the maple tree may want to move to the next range in the
tree, even if it stores a NULL.  This family of function provides that
functionality by advancing one slot at a time and returning the result,
while mas_contiguous() will iterate over the range and stop on
encountering the first NULL.

Link: https://lkml.kernel.org/r/20230518145544.1722059-29-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: introduce mas_next_slot() interface

Sometimes, during a tree walk, the user needs the next slot regardless of
if it is empty or not.  Add an interface to get the next slot.

Since there are no consecutive NULLs allowed in the tree, the mas_next()
function can only advance two slots at most.  So use the new
mas_next_slot() interface to align both implementations.  Use this method
for mas_find() as well.

Link: https://lkml.kernel.org/r/20230518145544.1722059-28-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: fix testing mas_empty_area()

Empty area will return -EINVAL if the search window is smaller than the
requested size.  Fix the test case to check for this error code.

Link: https://lkml.kernel.org/r/20230518145544.1722059-27-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: revise limit checks in mas_empty_area{_rev}()

Since the maple tree is inclusive in range, ensure that a range of 1 (min
= max) works for searching for a gap in either direction, and make sure
the size is at least 1 but not larger than the delta between min and max.

This commit also updates the testing.  Unfortunately there isn't a way to
safely update the tests and code without a test failure.

Link: https://lkml.kernel.org/r/20230518145544.1722059-26-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Suggested-by: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: try harder to keep active node with mas_prev()

Keep a reference to the node when possible with mas_prev().  This will
avoid re-walking the tree.  In keeping a reference to the node, keep the
last/index accurate to the range being referenced.  This means the limit
may be within the range, but the range may extend outside of the limit.

Also fix the single entry tree to respect the range (of 0), or set the
node to MAS_NONE in the case of shifting beyond 0.

Link: https://lkml.kernel.org/r/20230518145544.1722059-25-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: try harder to keep active node after mas_next()

Clean up the mas_next() call to try and keep a node reference when
possible.  This will avoid re-walking the tree in most cases.

Also clean up the single entry tree handling to ensure index/last are
consistent with what one would expect.  (returning NULL with limit of
1-oo).

Link: https://lkml.kernel.org/r/20230518145544.1722059-24-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/mmap: change do_vmi_align_munmap() for maple tree iterator changes

The maple tree iterator clean up is incompatible with the way
do_vmi_align_munmap() expects it to behave.  Update the expected behaviour
to map now since the change will work currently.

Link: https://lkml.kernel.org/r/20230518145544.1722059-23-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: mas_start() reset depth on dead node

When a dead node is detected, the depth has already been set to 1 so reset
it to 0.

Link: https://lkml.kernel.org/r/20230518145544.1722059-22-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: remove unnecessary check from mas_destroy()

mas_destroy currently checks if mas->node is MAS_START prior to calling
mas_start(), but this is unnecessary as mas_start() will do nothing if the
node is anything but MAS_START.

Link: https://lkml.kernel.org/r/20230518145544.1722059-21-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: add __init and __exit to test module

The test functions are not needed after the module is removed, so mark
them as such.  Add __exit to the module removal function.  Some other
variables have been marked as const static as well.

Link: https://lkml.kernel.org/r/20230518145544.1722059-20-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: update vma_iter_store() to use MAS_WARN_ON()

MAS_WARN_ON() will provide more information on the maple state and can be
more useful for debugging.  Use this version of WARN_ON() in the debugging
code when storing to the tree.

Update the printk to a pr_warn(), but this will only be printed when maple
tree debug is enabled anyways.

Making all print statements into one will keep them together on a busy
terminal.

Link: https://lkml.kernel.org/r/20230518145544.1722059-19-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: update validate_mm() to use vma iterator

Use the vma iterator in the validation code and combine the code to check
the maple tree into the main validate_mm() function.

Introduce a new function vma_iter_dump_tree() to dump the maple tree in
hex layout.

Replace all calls to validate_mm_mt() with validate_mm().

[Liam.Howlett@oracle.com: update validate_mm() to use vma iterator CONFIG flag]
Link: https://lkml.kernel.org/r/20230606183538.588190-1-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20230518145544.1722059-18-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: make test code work without debug enabled

The test code is less useful without debug, but can still do general
validations.  Define mt_dump(), mas_dump() and mas_wr_dump() as a noop if
debug is not enabled and document it in the test module information that
more information can be obtained with another kernel config option.

MT_BUG_ON() will report a failures without tree dumps, and the output will
be less useful.

Link: https://lkml.kernel.org/r/20230518145544.1722059-17-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: return error on mte_pivots() out of range

Rename mte_pivots() to mas_pivots() and pass through the ma_state to set
the error code to -EIO when the offset is out of range for the node type.
Change the WARN_ON() to MAS_WARN_ON() to log the maple state.

Link: https://lkml.kernel.org/r/20230518145544.1722059-16-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: use MAS_BUG_ON() prior to calling mas_meta_gap()

Replace the call to BUG_ON() in mas_meta_gap() with calls before the
function call MAS_BUG_ON() to get more information on error condition.

Link: https://lkml.kernel.org/r/20230518145544.1722059-15-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: use MAS_WR_BUG_ON() in mas_store_prealloc()

mas_store_prealloc() should never fail, but if it does due to internal
tree issues then get as much debug information as possible prior to
crashing the kernel.

Link: https://lkml.kernel.org/r/20230518145544.1722059-14-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: use MAS_BUG_ON() from mas_topiary_range()

In the even of trying to remove data from a leaf node by use of
mas_topiary_range(), log the maple state.

Link: https://lkml.kernel.org/r/20230518145544.1722059-13-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: use MAS_BUG_ON() in mas_set_height()

Use MAS_BUG_ON() instead of MT_BUG_ON() to get the maple state
information.  In the unlikely event of a tree height of > 31, try to
increase the probability of useful information being logged.

Link: https://lkml.kernel.org/r/20230518145544.1722059-12-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: use MAS_BUG_ON() when setting a leaf node as a parent

Use MAS_BUG_ON() to dump the maple state and tree in the unlikely event of
an issue.

Link: https://lkml.kernel.org/r/20230518145544.1722059-11-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: convert debug code to use MT_WARN_ON() and MAS_WARN_ON()

Using MT_WARN_ON() allows for the removal of if statements before logging.
Using MAS_WARN_ON() will provide more information when issues are
encountered.

Link: https://lkml.kernel.org/r/20230518145544.1722059-10-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: change RCU checks to WARN_ON() instead of BUG_ON()

If RCU is enabled and the tree isn't locked, just warn the user and avoid
crashing the kernel.

Link: https://lkml.kernel.org/r/20230518145544.1722059-9-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: convert BUG_ON() to MT_BUG_ON()

Use MT_BUG_ON() to get more information when running with MAPLE_TREE_DEBUG
enabled.

Link: https://lkml.kernel.org/r/20230518145544.1722059-8-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: add debug BUG_ON and WARN_ON variants

Add debug macros to dump the maple state and/or the tree for both warning
and bug_on calls.

Link: https://lkml.kernel.org/r/20230518145544.1722059-7-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: add format option to mt_dump()

Allow different formatting strings to be used when dumping the tree.
Currently supports hex and decimal.

Link: https://lkml.kernel.org/r/20230518145544.1722059-6-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: clean up mas_dfs_postorder()

Convert loop type to ensure all variables are set to make the compiler
happy, and use the mas_is_none() function instead of explicitly checking
the node in the maple state.

Link: https://lkml.kernel.org/r/20230518145544.1722059-5-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: avoid unnecessary ascending

The maple tree node limits are implied by the parent.  When walking up the
tree, the limit may not be known until a slot that does not have implied
limits are encountered.  However, if the node is the left-most or
right-most node, the walking up to find that limit can be skipped.

This commit also fixes the debug/testing code that was not setting the
limit on walking down the tree as that optimization is not compatible with
this change.

Link: https://lkml.kernel.org/r/20230518145544.1722059-4-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reviewed-by: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: clean up mas_parent_enum() and rename to mas_parent_type()

mas_parent_enum() is a simple wrapper for mte_parent_enum() which is only
called from that wrapper.  Remove the wrapper and inline mte_parent_enum()
into mas_parent_enum().

At the same time, clean up the bit masking of the root pointer since it
cannot be set by the time the bit masking occurs.  Change the check on the
root bit to a WARN_ON(), and fix the verification code to not trigger the
WARN_ON() before checking if the node is root.

Align the name to mas_parent_type() since mas_node_type() exists already.

Link: https://lkml.kernel.org/r/20230518145544.1722059-3-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: David Binderman <dcb314@hotmail.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

maple_tree: fix static analyser cppcheck issue

Patch series "Maple tree mas_{next,prev}_range() and cleanup", v4.

This patchset contains a number of clean ups to the code to make it more
usable (next/prev range), the addition of debug output formatting, the
addition of printing the maple state information in the WARN_ON/BUG_ON
code.

There is also work done here to keep nodes active during iterations to
reduce the necessity of re-walking the tree.

Finally, there is a new interface added to move to the next or previous
range in the tree, even if it is empty.

The organisation of the patches is as follows:

0001-0004 - Small clean ups
0005-0018 - Additional debug options and WARN_ON/BUG_ON changes
0019      - Test module __init and __exit addition
0020-0021 - More functional clean ups
0022-0026 - Changes to keep nodes active
0027-0034 - Add new mas_{prev,next}_range()
0035      - Use new mas_{prev,next}_range() in mmap_region()

This patch (of 35):

Static analyser of the maple tree code noticed that the split variable is
being used to dereference into an array prior to checking the variable
itself.  Fix this issue by changing the order of the statement to check
the variable first.

Link: https://lkml.kernel.org/r/20230518145544.1722059-1-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20230518145544.1722059-2-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: David Binderman <dcb314@hotmail.com>
Reviewed-by: Peng Zhang<zhangpeng.00@bytedance.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Vernon Yang <vernon2gm@gmail.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: convert migrate_pages() to work on folios

Almost all of the callers & implementors of migrate_pages() were already
converted to use folios.  compaction_alloc() & compaction_free() are
trivial to convert a part of this patch and not worth splitting out.

Link: https://lkml.kernel.org/r/20230513001101.276972-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/gup: remove vmas array from internal GUP functions

Now we have eliminated all callers to GUP APIs which use the vmas
parameter, eliminate it altogether.

This eliminates a class of bugs where vmas might have been kept around
longer than the mmap_lock and thus we need not be concerned about locks
being dropped during this operation leaving behind dangling pointers.

This simplifies the GUP API and makes it considerably clearer as to its
purpose - follow flags are applied and if pinning, an array of pages is
returned.

Link: https://lkml.kernel.org/r/6811b4b2b4b3baf3dd07f422bb18853bb2cd09fb.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/gup: remove vmas parameter from pin_user_pages()

We are now in a position where no caller of pin_user_pages() requires the
vmas parameter at all, so eliminate this parameter from the function and
all callers.

This clears the way to removing the vmas parameter from GUP altogether.

Link: https://lkml.kernel.org/r/195a99ae949c9f5cb589d2222b736ced96ec199a.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> [qib]
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> [drivers/media]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

io_uring: rsrc: delegate VMA file-backed check to GUP

Now that the GUP explicitly checks FOLL_LONGTERM pin_user_pages() for
broken file-backed mappings in "mm/gup: disallow FOLL_LONGTERM GUP-nonfast
writing to file-backed mappings", there is no need to explicitly check VMAs
for this condition, so simply remove this logic from io_uring altogether.

Link: https://lkml.kernel.org/r/e4a4efbda9cd12df71e0ed81796dc630231a1ef2.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/gup: remove vmas parameter from get_user_pages_remote()

The only instances of get_user_pages_remote() invocations which used the
vmas parameter were for a single page which can instead simply look up the
VMA directly. In particular:-

- __update_ref_ctr() looked up the VMA but did nothing with it so we simply
  remove it.

- __access_remote_vm() was already using vma_lookup() when the original
  lookup failed so by doing the lookup directly this also de-duplicates the
  code.

We are able to perform these VMA operations as we already hold the
mmap_lock in order to be able to call get_user_pages_remote().

As part of this work we add get_user_page_vma_remote() which abstracts the
VMA lookup, error handling and decrementing the page reference count should
the VMA lookup fail.

This forms part of a broader set of patches intended to eliminate the vmas
parameter altogether.

[akpm@linux-foundation.org: avoid passing NULL to PTR_ERR]
Link: https://lkml.kernel.org/r/d20128c849ecdbf4dd01cc828fcec32127ed939a.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> (for arm64)
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com> (for s390)
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/gup: remove unused vmas parameter from pin_user_pages_remote()

No invocation of pin_user_pages_remote() uses the vmas parameter, so
remove it.  This forms part of a larger patch set eliminating the use of
the vmas parameters altogether.

Link: https://lkml.kernel.org/r/28f000beb81e45bf538a2aaa77c90f5482b67a32.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/gup: remove unused vmas parameter from get_user_pages()

Patch series "remove the vmas parameter from GUP APIs", v6.

(pin_/get)_user_pages[_remote]() each provide an optional output parameter
for an array of VMA objects associated with each page in the input range.

These provide the means for VMAs to be returned, as long as mm->mmap_lock
is never released during the GUP operation (i.e.  the internal flag
FOLL_UNLOCKABLE is not specified).

In addition, these VMAs can only be accessed with the mmap_lock held and
become invalidated the moment it is released.

The vast majority of invocations do not use this functionality and of
those that do, all but one case retrieve a single VMA to perform checks
upon.

It is not egregious in the single VMA cases to simply replace the
operation with a vma_lookup().  In these cases we duplicate the (fast)
lookup on a slow path already under the mmap_lock, abstracted to a new
get_user_page_vma_remote() inline helper function which also performs
error checking and reference count maintenance.

The special case is io_uring, where io_pin_pages() specifically needs to
assert that the VMAs underlying the range do not result in broken
long-term GUP file-backed mappings.

As GUP now internally asserts that FOLL_LONGTERM mappings are not
file-backed in a broken fashion (i.e.  requiring dirty tracking) - as
implemented in "mm/gup: disallow FOLL_LONGTERM GUP-nonfast writing to
file-backed mappings" - this logic is no longer required and so we can
simply remove it altogether from io_uring.

Eliminating the vmas parameter eliminates an entire class of danging
pointer errors that might have occured should the lock have been
incorrectly released.

In addition, the API is simplified and now clearly expresses what it is
intended for - applying the specified GUP flags and (if pinning) returning
pinned pages.

This change additionally opens the door to further potential improvements
in GUP and the possible marrying of disparate code paths.

I have run this series against gup_test with no issues.

Thanks to Matthew Wilcox for suggesting this refactoring!

This patch (of 6):

No invocation of get_user_pages() use the vmas parameter, so remove it.

The GUP API is confusing and caveated.  Recent changes have done much to
improve that, however there is more we can do.  Exporting vmas is a prime
target as the caller has to be extremely careful to preclude their use
after the mmap_lock has expired or otherwise be left with dangling
pointers.

Removing the vmas parameter focuses the GUP functions upon their primary
purpose - pinning (and outputting) pages as well as performing the actions
implied by the input flags.

This is part of a patch series aiming to remove the vmas parameter
altogether.

Link: https://lkml.kernel.org/r/cover.1684350871.git.lstoakes@gmail.com
Link: https://lkml.kernel.org/r/589e0c64794668ffc799651e8d85e703262b1e9d.1684350871.git.lstoakes@gmail.com
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Christian König <christian.koenig@amd.com> (for radeon parts)
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sean Christopherson <seanjc@google.com> (KVM)
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/hugetlb: remove hugetlb_page_subpool()

All users of hugetlb_page_subpool() have been converted to use the folio
equivalent.  This function can be safely removed.

Link: https://lkml.kernel.org/r/20230516225205.1429196-1-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: move is_check_pages_enabled() into page_alloc.c

The is_check_pages_enabled() only used in page_alloc.c, move it into
page_alloc.c, also use it in free_tail_page_prepare().

Link: https://lkml.kernel.org/r/20230516063821.121844-14-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: move sysctls into it own fils

This moves all page alloc related sysctls to its own file, as part of the
kernel/sysctl.c spring cleaning, also move some functions declarations
from mm.h into internal.h.

Link: https://lkml.kernel.org/r/20230516063821.121844-13-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: vmscan: use gfp_has_io_fs()

Use gfp_has_io_fs() instead of open-code.

Link: https://lkml.kernel.org/r/20230516063821.121844-12-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: move pm_* function into power

pm_restrict_gfp_mask()/pm_restore_gfp_mask() only used in power, let's
move them out of page_alloc.c.

Adding a general gfp_has_io_fs() function which return true if gfp with
both __GFP_IO and __GFP_FS flags, then use it inside of
pm_suspended_storage(), also the pm_suspended_storage() is moved into
suspend.h.

Link: https://lkml.kernel.org/r/20230516063821.121844-11-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: move mark_free_page() into snapshot.c

The mark_free_page() is only used in kernel/power/snapshot.c, move it out
to reduce a bit of page_alloc.c

Link: https://lkml.kernel.org/r/20230516063821.121844-10-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: split out DEBUG_PAGEALLOC

Move DEBUG_PAGEALLOC related functions into a single file to reduce a bit
of page_alloc.c.

Link: https://lkml.kernel.org/r/20230516063821.121844-9-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: split out FAIL_PAGE_ALLOC

... to a single file to reduce a bit of page_alloc.c.

Link: https://lkml.kernel.org/r/20230516063821.121844-8-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: remove alloc_contig_dump_pages() stub

DEFINE_DYNAMIC_DEBUG_METADATA and DYNAMIC_DEBUG_BRANCH already has stub
definitions without dynamic debug feature, remove unnecessary
alloc_contig_dump_pages() stub.

Link: https://lkml.kernel.org/r/20230516063821.121844-7-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: squash page_is_consistent()

Squash the page_is_consistent() into bad_range() as there is only one
caller.

Link: https://lkml.kernel.org/r/20230516063821.121844-6-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: collect mem statistic into show_mem.c

Let's move show_mem.c from lib to mm, as it belongs memory subsystem, also
split some memory statistic related functions from page_alloc.c to
show_mem.c, and we cleanup some unneeded include.

There is no functional change.

Link: https://lkml.kernel.org/r/20230516063821.121844-5-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: move set_zone_contiguous() into mm_init.c

set_zone_contiguous() is only used in mm init/hotplug, and
clear_zone_contiguous() only used in hotplug, move them from page_alloc.c
to the more appropriate file.

Link: https://lkml.kernel.org/r/20230516063821.121844-4-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: move init_on_alloc/free() into mm_init.c

Since commit f2fc4b44ec2b ("mm: move init_mem_debugging_and_hardening() to
mm/mm_init.c"), the init_on_alloc() and init_on_free() define is better to
move there too.

Link: https://lkml.kernel.org/r/20230516063821.121844-3-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: page_alloc: move mirrored_kernelcore into mm_init.c

Patch series "mm: page_alloc: misc cleanup and refactor", v2.

This aims to reduce more space in page_alloc.c, also do some cleanup, no
functional changes intended.

This patch (of 13):

Since commit 9420f89db2dd ("mm: move most of core MM initialization to
mm/mm_init.c"), mirrored_kernelcore should be moved into mm_init.c, as
most related codes are already there.

Link: https://lkml.kernel.org/r/20230516063821.121844-1-wangkefeng.wang@huawei.com
Link: https://lkml.kernel.org/r/20230516063821.121844-2-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/zsmalloc: get rid of PAGE_MASK

Use offset_in_page() macro instead of 'val & ~PAGE_MASK'

Link: https://lkml.kernel.org/r/20230516095029.49036-2-avromanov@sberdevices.ru
Signed-off-by: Alexey Romanov <avromanov@sberdevices.ru>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/secretmem: make it on by default

Following the discussion about direct map fragmentaion at LSF/MM [1], it
appears that direct map fragmentation has a negligible effect on kernel
data accesses.  Since the only reason that warranted secretmem to be
disabled by default was concern about performance regression caused by the
direct map fragmentation, it makes perfect sense to lift this restriction
and make secretmem enabled.

secretmem obeys RLIMIT_MEMBLOCK and as such it is not expected to cause
large fragmentation of the direct map or meaningfull increase in page
tables allocated during split of the large mappings in the direct map.

The secretmem.enable parameter is retained to allow system administrators
to disable secretmem at boot.

Switch the default setting of secretmem.enable parameter to 1.

Link: https://lwn.net/Articles/931406/
Link: https://lkml.kernel.org/r/20230515083400.3563974-1-rppt@kernel.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Revert "Revert "mm/compaction: fix set skip in fast_find_migrateblock""

This reverts commit 95e7a450b819 ("Revert "mm/compaction: fix set skip in
fast_find_migrateblock"").

Commit 7efc3b726103 ("mm/compaction: fix set skip in
fast_find_migrateblock") was reverted due to bug reports about khugepaged
consuming large amounts of CPU without making progress.  The underlying
bug was partially fixed by commit cfccd2e63e7e ("mm, compaction: finish
pageblocks on complete migration failure") but it only mitigated the
problem and Vlastimil Babka pointing out the same issue could
theoretically happen to kcompactd.

As pageblocks containing pages that fail to migrate should now be forcibly
rescanned to set the skip hint if skip hints are used,
fast_find_migrateblock() should no longer loop on a small subset of
pageblocks for prolonged periods of time.  Revert the revert so
fast_find_migrateblock() is effective again.

Using the mmtests config workload-usemem-stress-numa-compact, the number
of unique ranges scanned was analysed for both kcompactd and !kcompactd
activity.

6.4.0-rc1-vanilla
kcompactd
      7 range=(0x10d600~0x10d800)
      7 range=(0x110c00~0x110e00)
      7 range=(0x110e00~0x111000)
      7 range=(0x111800~0x111a00)
      7 range=(0x111a00~0x111c00)
!kcompactd
      1 range=(0x113e00~0x114000)
      1 range=(0x114000~0x114020)
      1 range=(0x114400~0x114489)
      1 range=(0x114489~0x1144aa)
      1 range=(0x1144aa~0x114600)

6.4.0-rc1-mm-revertfastmigrate
kcompactd
     17 range=(0x104200~0x104400)
     17 range=(0x104400~0x104600)
     17 range=(0x104600~0x104800)
     17 range=(0x104800~0x104a00)
     17 range=(0x104a00~0x104c00)
!kcompactd
   1793 range=(0x15c200~0x15c400)
   5436 range=(0x105800~0x105a00)
  19826 range=(0x150a00~0x150c00)
  19833 range=(0x150800~0x150a00)
  19834 range=(0x11ce00~0x11d000)

6.4.0-rc1-mm-follupfastfind
kcompactd
     22 range=(0x107200~0x107400)
     23 range=(0x107400~0x107600)
     23 range=(0x107600~0x107800)
     23 range=(0x107c00~0x107e00)
     23 range=(0x107e00~0x108000)
!kcompactd
      3 range=(0x890240~0x890400)
      5 range=(0x886e00~0x887000)
      5 range=(0x88a400~0x88a600)
      6 range=(0x88f800~0x88fa00)
      9 range=(0x88a400~0x88a420)

Note that the vanilla kernel and the full series had some duplication of
ranges scanned but it was not severe and would be in line with compaction
resets when the skip hints are cleared.  Just a revert of commit
7efc3b726103 ("mm/compaction: fix set skip in fast_find_migrateblock")
showed excessive rescans of the same ranges so the series should not
reintroduce bug 1206848.

Link: https://bugzilla.suse.com/show_bug.cgi?id=1206848
Link: https://lkml.kernel.org/r/20230515113344.6869-5-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Raghavendra K T <raghavendra.kt@amd.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Chuyi Zhou <zhouchuyi@bytedance.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: update pageblock skip when first migration candidate is not at the start

isolate_migratepages_block should mark a pageblock as skip if scanning
started on an aligned pageblock boundary but it only updates the skip flag
if the first migration candidate is also aligned.  Tracing during a
compaction stress load (mmtests: workload-usemem-stress-numa-compact) that
many pageblocks are not marked skip causing excessive scanning of blocks
that had been recently checked.  Update pageblock skip based on
"valid_page" which is set if scanning started on a pageblock boundary.

[mgorman@techsingularity.net: fix handling of skip bit]
Link: https://lkml.kernel.org/r/20230602111622.swtxhn6lu2qwgrwq@techsingularity.net
Link: https://lkml.kernel.org/r/20230515113344.6869-4-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Raghavendra K T <raghavendra.kt@amd.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Chuyi Zhou <zhouchuyi@bytedance.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: compaction: only force pageblock scan completion when skip hints are obeyed

fast_find_migrateblock relies on skip hints to avoid rescanning a recently
selected pageblock but compact_zone() only forces the pageblock scan
completion to set the skip hint if in direct compaction.  While this
prevents direct compaction repeatedly scanning a subset of blocks due to
fast_find_migrateblock(), it does not prevent proactive compaction, node
compaction and kcompactd encountering the same problem described in commit
cfccd2e63e7e ("mm, compaction: finish pageblocks on complete migration
failure").

Force the scan completion of a pageblock to set the skip hint if skip
hints are obeyed to prevent fast_find_migrateblock() repeatedly selecting
a subset of pageblocks.

Link: https://lkml.kernel.org/r/20230515113344.6869-3-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Raghavendra K T <raghavendra.kt@amd.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Chuyi Zhou <zhouchuyi@bytedance.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>