asm-generic: pgalloc: provide generic __pgd_{alloc,free}

We already have a generic implementation of alloc/free up to P4D level, as
well as pgd_free(). Let's finish the work and add a generic PGD-l

asm-generic: pgalloc: provide generic __pgd_{alloc,free}

We already have a generic implementation of alloc/free up to P4D level, as
well as pgd_free(). Let's finish the work and add a generic PGD-level
alloc helper as well.

Unlike at lower levels, almost all architectures need some specific magic
at PGD level (typically initialising PGD entries), so introducing a
generic pgd_alloc() isn't worth it. Instead we introduce two new helpers,
__pgd_alloc() and __pgd_free(), and make use of them in the arch-specific
pgd_alloc() and pgd_free() wherever possible. To accommodate as many arch
as possible, __pgd_alloc() takes a page allocation order.

Because pagetable_alloc() allocates zeroed pages, explicit zeroing in
pgd_alloc() becomes redundant and we can get rid of it. Some trivial
implementations of pgd_free() also become unnecessary once __pgd_alloc()
is used; remove them.

Another small improvement is consistent accounting of PGD pages by using
GFP_PGTABLE_{USER,KERNEL} as appropriate.

Not all PGD allocations can be handled by the generic helpers. In
particular, multiple architectures allocate PGDs from a kmem_cache, and
those PGDs may not be page-sized.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Kevin Brodsky <[email protected]>
Acked-by: Dave Hansen <[email protected]>
Acked-by: Qi Zheng <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Linus Walleij <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Cc: Mike Rapoport (Microsoft) <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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ARC: mm: support 4 levels of page tables

Acked-by: Mike Rapoport <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>

ARC: mm: support 3 levels of page tables

ARCv2 MMU is software walked and Linux implements 2 levels of paging: pgd/pte.
Forthcoming hw will have multiple levels, so this change preps mm code
for sam

ARC: mm: support 3 levels of page tables

ARCv2 MMU is software walked and Linux implements 2 levels of paging: pgd/pte.
Forthcoming hw will have multiple levels, so this change preps mm code
for same. It is also fun to try multi levels even on soft-walked code to
ensure generic mm code is robust to handle.

overview
________

2 levels {pgd, pte} : pmd is folded but pmd_* macros are valid and operate on pgd
3 levels {pgd, pmd, pte}:
- pud is folded and pud_* macros point to pgd
- pmd_* macros operate on actual pmd

code changes
____________

1. #include <asm-generic/pgtable-nopud.h>

2. Define CONFIG_PGTABLE_LEVELS 3

3a. Define PMD_SHIFT, PMD_SIZE, PMD_MASK, pmd_t
3b. Define pmd_val() which actually deals with pmd
(pmd_offset(), pmd_index() are provided by generic code)
3c. pmd_alloc_one()/pmd_free() also provided by generic code
(pmd_populate/pmd_free already exist)

4. Define pud_none(), pud_bad() macros based on generic pud_val() which
internally pertains to pgd now.
4b. define pud_populate() to just setup pgd

Acked-by: Mike Rapoport <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>

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ARC: mm: switch to asm-generic/pgalloc.h

With previous patch ARC pgalloc functions are same as generic, hence
switch to that.

Suggested-by: Mike Rapoport <[email protected]>
Acked-by: Mike Rapopor

ARC: mm: switch to asm-generic/pgalloc.h

With previous patch ARC pgalloc functions are same as generic, hence
switch to that.

Suggested-by: Mike Rapoport <[email protected]>
Acked-by: Mike Rapoport <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>

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ARC: mm: switch pgtable_t back to struct page *

So far ARC pgtable_t has not been struct page based to avoid extra
page_address() calls involved. However the differences are down to
noise and get in

ARC: mm: switch pgtable_t back to struct page *

So far ARC pgtable_t has not been struct page based to avoid extra
page_address() calls involved. However the differences are down to
noise and get in the way of using generic code, hence this patch.

This also allows us to reuse generic THP depost/withdraw code.

There's some additional consideration for PGDIR_SHIFT in 4K page config.
Now due to page tables being PAGE_SIZE deep only, the address split
can't be really arbitrary.

Tested-by: kernel test robot <[email protected]>
Suggested-by: Mike Rapoport <[email protected]>
Acked-by: Mike Rapoport <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>

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ARC: mm: pmd_populate* to use the canonical set_pmd (and drop pmd_set)

Signed-off-by: Vineet Gupta <[email protected]>

mm/thp: define default pmd_pgtable()

Currently most platforms define pmd_pgtable() as pmd_page() duplicating
the same code all over. Instead just define a default value i.e
pmd_page() for pmd_pgtab

mm/thp: define default pmd_pgtable()

Currently most platforms define pmd_pgtable() as pmd_page() duplicating
the same code all over. Instead just define a default value i.e
pmd_page() for pmd_pgtable() and let platforms override when required via
<asm/pgtable.h>. All the existing platform that override pmd_pgtable()
have been moved into their respective <asm/pgtable.h> header in order to
precede before the new generic definition. This makes it much cleaner
with reduced code.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Anshuman Khandual <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Acked-by: Mike Rapoport <[email protected]>
Cc: Nick Hu <[email protected]>
Cc: Richard Henderson <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Guo Ren <[email protected]>
Cc: Brian Cain <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Ley Foon Tan <[email protected]>
Cc: Jonas Bonn <[email protected]>
Cc: Stefan Kristiansson <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: "James E.J. Bottomley" <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jeff Dike <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Chris Zankel <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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ARC: pgalloc.h: delete a duplicated word + other fixes

Drop the repeated word "to".
Change "Thay" to "That".
Add a closing right parenthesis.

Signed-off-by: Randy Dunlap <[email protected]>
Cc:

ARC: pgalloc.h: delete a duplicated word + other fixes

Drop the repeated word "to".
Change "Thay" to "That".
Add a closing right parenthesis.

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: [email protected]
Signed-off-by: Vineet Gupta <[email protected]>

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mm: treewide: clarify pgtable_page_{ctor,dtor}() naming

The naming of pgtable_page_{ctor,dtor}() seems to have confused a few
people, and until recently arm64 used these erroneously/pointlessly for

mm: treewide: clarify pgtable_page_{ctor,dtor}() naming

The naming of pgtable_page_{ctor,dtor}() seems to have confused a few
people, and until recently arm64 used these erroneously/pointlessly for
other levels of page table.

To make it incredibly clear that these only apply to the PTE level, and to
align with the naming of pgtable_pmd_page_{ctor,dtor}(), let's rename them
to pgtable_pte_page_{ctor,dtor}().

These changes were generated with the following shell script:

----
git grep -lw 'pgtable_page_.tor' | while read FILE; do
sed -i '{s/pgtable_page_ctor/pgtable_pte_page_ctor/}' $FILE;
sed -i '{s/pgtable_page_dtor/pgtable_pte_page_dtor/}' $FILE;
done
----

... with the documentation re-flowed to remain under 80 columns, and
whitespace fixed up in macros to keep backslashes aligned.

There should be no functional change as a result of this patch.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Mark Rutland <[email protected]>
Reviewed-by: Mike Rapoport <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]> [m68k]
Cc: Anshuman Khandual <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Yu Zhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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mm: remove quicklist page table caches

Patch series "mm: remove quicklist page table caches".

A while ago Nicholas proposed to remove quicklist page table caches [1].

I've rebased his patch on the

mm: remove quicklist page table caches

Patch series "mm: remove quicklist page table caches".

A while ago Nicholas proposed to remove quicklist page table caches [1].

I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.

[1] https://lore.kernel.org/linux-mm/[email protected]

This patch (of 3):

Remove page table allocator "quicklists". These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.

The numbers in the initial commit look interesting but probably don't
apply anymore. If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.

Also it might be better to instead make more general improvements to page
allocator if this is still so slow.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Nicholas Piggin <[email protected]>
Signed-off-by: Mike Rapoport <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Enrico Weigelt <[email protected]>
Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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mm: treewide: remove unused address argument from pte_alloc functions

Patch series "Add support for fast mremap".

This series speeds up the mremap(2) syscall by copying page tables at
the PMD level

mm: treewide: remove unused address argument from pte_alloc functions

Patch series "Add support for fast mremap".

This series speeds up the mremap(2) syscall by copying page tables at
the PMD level even for non-THP systems. There is concern that the extra
'address' argument that mremap passes to pte_alloc may do something
subtle architecture related in the future that may make the scheme not
work. Also we find that there is no point in passing the 'address' to
pte_alloc since its unused. This patch therefore removes this argument
tree-wide resulting in a nice negative diff as well. Also ensuring
along the way that the enabled architectures do not do anything funky
with the 'address' argument that goes unnoticed by the optimization.

Build and boot tested on x86-64. Build tested on arm64. The config
enablement patch for arm64 will be posted in the future after more
testing.

The changes were obtained by applying the following Coccinelle script.
(thanks Julia for answering all Coccinelle questions!).
Following fix ups were done manually:
* Removal of address argument from pte_fragment_alloc
* Removal of pte_alloc_one_fast definitions from m68k and microblaze.

// Options: --include-headers --no-includes
// Note: I split the 'identifier fn' line, so if you are manually
// running it, please unsplit it so it runs for you.

virtual patch

@pte_alloc_func_def depends on patch exists@
identifier E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
type T2;
@@

fn(...
- , T2 E2
)
{ ... }

@pte_alloc_func_proto_noarg depends on patch exists@
type T1, T2, T3, T4;
identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1, T2);
+ T3 fn(T1);
|
- T3 fn(T1, T2, T4);
+ T3 fn(T1, T2);
)

@pte_alloc_func_proto depends on patch exists@
identifier E1, E2, E4;
type T1, T2, T3, T4;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1 E1, T2 E2);
+ T3 fn(T1 E1);
|
- T3 fn(T1 E1, T2 E2, T4 E4);
+ T3 fn(T1 E1, T2 E2);
)

@pte_alloc_func_call depends on patch exists@
expression E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

fn(...
-, E2
)

@pte_alloc_macro depends on patch exists@
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
identifier a, b, c;
expression e;
position p;
@@

(
- #define fn(a, b, c) e
+ #define fn(a, b) e
|
- #define fn(a, b) e
+ #define fn(a) e
)

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Joel Fernandes (Google) <[email protected]>
Suggested-by: Kirill A. Shutemov <[email protected]>
Acked-by: Kirill A. Shutemov <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Julia Lawall <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: William Kucharski <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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arc: get rid of superfluous __GFP_REPEAT

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pte_alloc_one_kernel u

arc: get rid of superfluous __GFP_REPEAT

__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.

pte_alloc_one_kernel uses __get_order_pte but this is obviously always
zero because BITS_FOR_PTE is not larger than 9 yet the page size is
always larger than 4K. This means that this flag has never been
actually useful here because it has always been used only for
PAGE_ALLOC_COSTLY requests.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Michal Hocko <[email protected]>
Acked-by: Vineet Gupta <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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ARC: mm: PAE40 support

This is the first working implementation of 40-bit physical address
extension on ARCv2.

Signed-off-by: Alexey Brodkin <[email protected]>
Signed-off-by: Vineet Gupta <vgu

ARC: mm: PAE40 support

This is the first working implementation of 40-bit physical address
extension on ARCv2.

Signed-off-by: Alexey Brodkin <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>

show more ...

ARC: mm: switch pgtable_to to pte_t *

ARC is the only arch with unsigned long type (vs. struct page *).
Historically this was done to avoid the page_address() calls in various
arch hooks which need

ARC: mm: switch pgtable_to to pte_t *

ARC is the only arch with unsigned long type (vs. struct page *).
Historically this was done to avoid the page_address() calls in various
arch hooks which need to get the virtual/logical address of the table.

Some arches alternately define it as pte_t *, and is as efficient as
unsigned long (generated code doesn't change)

Suggested-by: Kirill A. Shutemov <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>

show more ...

arc: handle pgtable_page_ctor() fail

Signed-off-by: Kirill A. Shutemov <[email protected]>
Acked-by: Vineet Gupta <[email protected]> [for arch/arc bits]
Signed-off-by: Andrew Morton

arc: handle pgtable_page_ctor() fail

Signed-off-by: Kirill A. Shutemov <[email protected]>
Acked-by: Vineet Gupta <[email protected]> [for arch/arc bits]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

ARC: Page Table Management

Signed-off-by: Vineet Gupta <[email protected]>