linux.git/arch/arm/include/asm/pgtable-2level.h, branch v5.9

mm: consolidate pte_index() and pte_offset_*() definitions

2020-06-09T16:39:14+00:00

All architectures define pte_index() as

	(address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)

and all architectures define pte_offset_kernel() as an entry in the array
of PTEs indexed by the pte_index().

For the most architectures the pte_offset_kernel() implementation relies
on the availability of pmd_page_vaddr() that converts a PMD entry value to
the virtual address of the page containing PTEs array.

Let's move x86 definitions of the PTE accessors to the generic place in
 and then simply drop the respective definitions from the
other architectures.

The architectures that didn't provide pmd_page_vaddr() are updated to have
that defined.

The generic implementation of pte_offset_kernel() can be overridden by an
architecture and alpha makes use of this because it has special ordering
requirements for its version of pte_offset_kernel().

[rppt@linux.ibm.com: v2]
  Link: http://lkml.kernel.org/r/20200514170327.31389-11-rppt@kernel.org
[rppt@linux.ibm.com: update]
  Link: http://lkml.kernel.org/r/20200514170327.31389-12-rppt@kernel.org
[rppt@linux.ibm.com: update]
  Link: http://lkml.kernel.org/r/20200514170327.31389-13-rppt@kernel.org
[akpm@linux-foundation.org: fix x86 warning]
[sfr@canb.auug.org.au: fix powerpc build]
  Link: http://lkml.kernel.org/r/20200607153443.GB738695@linux.ibm.com

Signed-off-by: Mike Rapoport 
Signed-off-by: Stephen Rothwell 
Signed-off-by: Andrew Morton 
Cc: Arnd Bergmann 
Cc: Borislav Petkov 
Cc: Brian Cain 
Cc: Catalin Marinas 
Cc: Chris Zankel 
Cc: "David S. Miller" 
Cc: Geert Uytterhoeven 
Cc: Greentime Hu 
Cc: Greg Ungerer 
Cc: Guan Xuetao 
Cc: Guo Ren 
Cc: Heiko Carstens 
Cc: Helge Deller 
Cc: Ingo Molnar 
Cc: Ley Foon Tan 
Cc: Mark Salter 
Cc: Matthew Wilcox 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Nick Hu 
Cc: Paul Walmsley 
Cc: Richard Weinberger 
Cc: Rich Felker 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: Vincent Chen 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Link: http://lkml.kernel.org/r/20200514170327.31389-10-rppt@kernel.org
Signed-off-by: Linus Torvalds

mm/special: create generic fallbacks for pte_special() and pte_mkspecial()

2020-04-10T22:36:21+00:00

Currently there are many platforms that dont enable ARCH_HAS_PTE_SPECIAL
but required to define quite similar fallback stubs for special page
table entry helpers such as pte_special() and pte_mkspecial(), as they
get build in generic MM without a config check.  This creates two
generic fallback stub definitions for these helpers, eliminating much
code duplication.

mips platform has a special case where pte_special() and pte_mkspecial()
visibility is wider than what ARCH_HAS_PTE_SPECIAL enablement requires.
This restricts those symbol visibility in order to avoid redefinitions
which is now exposed through this new generic stubs and subsequent build
failure.  arm platform set_pte_at() definition needs to be moved into a
C file just to prevent a build failure.

[anshuman.khandual@arm.com: use defined(CONFIG_ARCH_HAS_PTE_SPECIAL) in mips per Thomas]
  Link: http://lkml.kernel.org/r/1583851924-21603-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual 
Signed-off-by: Andrew Morton 
Acked-by: Guo Ren 			[csky]
Acked-by: Geert Uytterhoeven 	[m68k]
Acked-by: Stafford Horne 		[openrisc]
Acked-by: Helge Deller 			[parisc]
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Cc: Matt Turner 
Cc: Russell King 
Cc: Brian Cain 
Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: Sam Creasey 
Cc: Michal Simek 
Cc: Ralf Baechle 
Cc: Paul Burton 
Cc: Nick Hu 
Cc: Greentime Hu 
Cc: Vincent Chen 
Cc: Ley Foon Tan 
Cc: Jonas Bonn 
Cc: Stefan Kristiansson 
Cc: "James E.J. Bottomley" 
Cc: "David S. Miller" 
Cc: Jeff Dike 
Cc: Richard Weinberger 
Cc: Anton Ivanov 
Cc: Guan Xuetao 
Cc: Chris Zankel 
Cc: Max Filippov 
Cc: Thomas Bogendoerfer 
Link: http://lkml.kernel.org/r/1583802551-15406-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds

arm: mm: add p?d_leaf() definitions

2020-02-04T03:05:24+00:00

walk_page_range() is going to be allowed to walk page tables other than
those of user space.  For this it needs to know when it has reached a
'leaf' entry in the page tables.  This information is provided by the
p?d_leaf() functions/macros.

For arm pmd_large() already exists and does what we want.  So simply
provide the generic pmd_leaf() name.

Link: http://lkml.kernel.org/r/20191218162402.45610-4-steven.price@arm.com
Signed-off-by: Steven Price 
Cc: Russell King 
Cc: Albert Ou 
Cc: Alexandre Ghiti 
Cc: Andy Lutomirski 
Cc: Ard Biesheuvel 
Cc: Arnd Bergmann 
Cc: Benjamin Herrenschmidt 
Cc: Borislav Petkov 
Cc: Catalin Marinas 
Cc: Christian Borntraeger 
Cc: Dave Hansen 
Cc: David S. Miller 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: James Hogan 
Cc: James Morse 
Cc: Jerome Glisse 
Cc: "Liang, Kan" 
Cc: Mark Rutland 
Cc: Michael Ellerman 
Cc: Paul Burton 
Cc: Paul Mackerras 
Cc: Paul Walmsley 
Cc: Peter Zijlstra 
Cc: Ralf Baechle 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Zong Li 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

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

2019-06-19T15:09:55+00:00

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 
Reviewed-by: Enrico Weigelt 
Reviewed-by: Kate Stewart 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman

mm: make the __PAGETABLE_PxD_FOLDED defines non-empty

2018-11-02T07:31:52+00:00

Change the currently empty defines for __PAGETABLE_PMD_FOLDED,
__PAGETABLE_PUD_FOLDED and __PAGETABLE_P4D_FOLDED to return 1.
This makes it possible to use __is_defined() to test if the
preprocessor define exists.

Acked-by: Kirill A. Shutemov 
Signed-off-by: Martin Schwidefsky

ARM: 8578/1: mm: ensure pmd_present only checks the valid bit

2016-06-09T16:51:47+00:00

In a subsequent patch, pmd_mknotpresent will clear the valid bit of the
pmd entry, resulting in a not-present entry from the hardware's
perspective. Unfortunately, pmd_present simply checks for a non-zero pmd
value and will therefore continue to return true even after a
pmd_mknotpresent operation. Since pmd_mknotpresent is only used for
managing huge entries, this is only an issue for the 3-level case.

This patch fixes the 3-level pmd_present implementation to take into
account the valid bit. For bisectability, the change is made before the
fix to pmd_mknotpresent.

[catalin.marinas@arm.com: comment update regarding pmd_mknotpresent patch]

Fixes: 8d9625070073 ("ARM: mm: Transparent huge page support for LPAE systems.")
Cc:  # 3.11+
Cc: Russell King 
Cc: Steve Capper 
Signed-off-by: Will Deacon 
Signed-off-by: Catalin Marinas 
Signed-off-by: Russell King

ARM: pgtable: document mapping types

2015-07-03T16:06:57+00:00

Signed-off-by: Russell King

arm: define __PAGETABLE_PMD_FOLDED for !LPAE

2015-02-12T01:06:04+00:00

ARM uses custom implementation of PMD folding in 2-level page table case.
Generic code expects to see __PAGETABLE_PMD_FOLDED to be defined if PMD is
folded, but ARM doesn't do this.  Let's fix it.

Defining __PAGETABLE_PMD_FOLDED will drop out unused __pmd_alloc().  It
also fixes problems with recently-introduced pmd accounting on ARM without
LPAE.

Signed-off-by: Kirill A. Shutemov 
Reported-by: Nishanth Menon 
Reported-by: Simon Horman 
Tested-by: Simon Horman 
Tested-by: Fabio Estevam 
Tested-by: Felipe Balbi 
Tested-by: Nishanth Menon 
Tested-by: Peter Ujfalusi 
Tested-by: Krzysztof Kozlowski 
Tested-by: Geert Uytterhoeven 
Cc: Dave Hansen 
Cc: Hugh Dickins 
Cc: Cyrill Gorcunov 
Cc: Pavel Emelyanov 
Cc: David Rientjes 
Cc: Russell King 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arm: drop L_PTE_FILE and pte_file()-related helpers

2015-02-10T22:30:31+00:00

We've replaced remap_file_pages(2) implementation with emulation.  Nobody
creates non-linear mapping anymore.

This patch also adjust __SWP_TYPE_SHIFT, effectively increase size of
possible swap file to 128G.

Signed-off-by: Kirill A. Shutemov 
Cc: Russell King 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

arm: mm: introduce special ptes for LPAE

2014-10-10T02:26:00+00:00

We need a mechanism to tag ptes as being special, this indicates that no
attempt should be made to access the underlying struct page * associated
with the pte.  This is used by the fast_gup when operating on ptes as it
has no means to access VMAs (that also contain this information)
locklessly.

The L_PTE_SPECIAL bit is already allocated for LPAE, this patch modifies
pte_special and pte_mkspecial to make use of it, and defines
__HAVE_ARCH_PTE_SPECIAL.

This patch also excludes special ptes from the icache/dcache sync logic.

Signed-off-by: Steve Capper 
Reviewed-by: Catalin Marinas 
Cc: Dann Frazier 
Cc: Hugh Dickins 
Cc: Russell King 
Cc: Mark Rutland 
Cc: Mel Gorman 
Cc: Will Deacon 
Cc: Christoffer Dall 
Cc: Andrea Arcangeli 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds