[PATCH v2 00/19] ARC mm updates: support 3/4 levels and asm-generic/pgalloc

From: Vineet Gupta
Date: Thu Aug 12 2021 - 19:38:00 EST


Hi,

Big pile of ARC mm changes to prepare for 3 or 4 levels of paging (from
current 2) needed for new hardware page walked MMUv6 (in aRCv3 ISA based
cores).

Most of these changes are incremental cleanups to make way for 14/18 and
15/18 which actually imeplement the new levels (in existing ARCv2 port)
and worth a critical eye.

CC'ing some of you guys dealing with page tables for a while :-)
to spot any obvious gotchas.

Thx,
-Vineet

Changes since v1 [1]
- Switched ARC to asm-generic/pgalloc.h (so struct page based pgtable_t) [Mike Rapoport]
- Dropped {pud,pmd}_alloc_one/{pud,pmd}_free provided by asm-generic/pgalloc.h [Mike Rapoport]
- Negative diffstat now due to above
- Added BUILD_BUG_ON() to arch/arc/mm/init.c for sanity of table sizes
- Consolidated 2 patches related to ARC_USE_SCRATCH_REG [Mike Rapoport]
- Reworked how mmu is re-enabled in entry code [Jose Abreu]

[1] http://lists.infradead.org/pipermail/linux-snps-arc/2021-August/005326.html

Vineet Gupta (19):
ARC: mm: use SCRATCH_DATA0 register for caching pgdir in ARCv2 only
ARC: mm: remove tlb paranoid code
ARC: mm: move mmu/cache externs out to setup.h
ARC: mm: Fixes to allow STRICT_MM_TYPECHECKS
ARC: mm: Enable STRICT_MM_TYPECHECKS
ARC: ioremap: use more commonly used PAGE_KERNEL based uncached flag
ARC: mm: pmd_populate* to use the canonical set_pmd (and drop pmd_set)
ARC: mm: switch pgtable_t back to struct page *
ARC: mm: switch to asm-generic/pgalloc.h
ARC: mm: non-functional code cleanup ahead of 3 levels
ARC: mm: move MMU specific bits out of ASID allocator
ARC: mm: move MMU specific bits out of entry code ...
ARC: mm: disintegrate mmu.h (arcv2 bits out)
ARC: mm: disintegrate pgtable.h into levels and flags
ARC: mm: hack to allow 2 level build with 4 level code
ARC: mm: support 3 levels of page tables
ARC: mm: support 4 levels of page tables
ARC: mm: vmalloc sync from kernel to user table to update PMD ...
ARC: mm: introduce _PAGE_TABLE to explicitly link pgd,pud,pmd entries

arch/arc/Kconfig | 7 +-
arch/arc/include/asm/cache.h | 4 -
arch/arc/include/asm/entry-compact.h | 8 -
arch/arc/include/asm/mmu-arcv2.h | 103 +++++++
arch/arc/include/asm/mmu.h | 73 +----
arch/arc/include/asm/mmu_context.h | 28 +-
arch/arc/include/asm/page.h | 74 +++--
arch/arc/include/asm/pgalloc.h | 81 ++----
arch/arc/include/asm/pgtable-bits-arcv2.h | 151 +++++++++++
arch/arc/include/asm/pgtable-levels.h | 179 ++++++++++++
arch/arc/include/asm/pgtable.h | 315 +---------------------
arch/arc/include/asm/processor.h | 2 +-
arch/arc/include/asm/setup.h | 12 +-
arch/arc/kernel/entry-arcv2.S | 1 +
arch/arc/kernel/entry.S | 7 +-
arch/arc/mm/fault.c | 20 +-
arch/arc/mm/init.c | 5 +
arch/arc/mm/ioremap.c | 3 +-
arch/arc/mm/tlb.c | 68 +----
arch/arc/mm/tlbex.S | 78 ++----
20 files changed, 591 insertions(+), 628 deletions(-)
create mode 100644 arch/arc/include/asm/mmu-arcv2.h
create mode 100644 arch/arc/include/asm/pgtable-bits-arcv2.h
create mode 100644 arch/arc/include/asm/pgtable-levels.h

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2.25.1