The MM subsystem is trying to shrink struct page. This patchset introduces a memory descriptor for page table tracking - struct ptdesc. This patchset introduces ptdesc, splits ptdesc from struct page, and converts many callers of page table constructor/destructors to use ptdescs. Ptdesc is a foundation to further standardize page tables, and eventually allow for dynamic allocation of page tables independent of struct page. However, the use of pages for page table tracking is quite deeply ingrained and varied across archictectures, so there is still a lot of work to be done before that can happen. This is rebased on next-20230626. There is a minor conflict with patch 24 and the mm-unstable tree in arch/m68k/mm/motorola.c - The end result of applying the patch should be the same. v6: Fix compiler warnings/errors v5: More Acked-bys :) Cleanup some documentation wording and formatting Add pt_rcu_head to ptdesc Add memcg to ptdesc (and align it with struct page) Ensure all get_free_page() callers prohibit HIGHMEM for 32 bit support. Renamed folio_{set, clear}_table() to folio_{set, clear}_pgtable() Removed pagetable_clear() as it is not necessary right now Dropped s390 _refcount to _pt_frag_refcount conversion Vishal Moola (Oracle) (33): mm: Add PAGE_TYPE_OP folio functions s390: Use _pt_s390_gaddr for gmap address tracking pgtable: Create struct ptdesc mm: add utility functions for ptdesc mm: Convert pmd_pgtable_page() to pmd_ptdesc() mm: Convert ptlock_alloc() to use ptdescs mm: Convert ptlock_ptr() to use ptdescs mm: Convert pmd_ptlock_init() to use ptdescs mm: Convert ptlock_init() to use ptdescs mm: Convert pmd_ptlock_free() to use ptdescs mm: Convert ptlock_free() to use ptdescs mm: Create ptdesc equivalents for pgtable_{pte,pmd}_page_{ctor,dtor} powerpc: Convert various functions to use ptdescs x86: Convert various functions to use ptdescs s390: Convert various gmap functions to use ptdescs s390: Convert various pgalloc functions to use ptdescs mm: Remove page table members from struct page pgalloc: Convert various functions to use ptdescs arm: Convert various functions to use ptdescs arm64: Convert various functions to use ptdescs csky: Convert __pte_free_tlb() to use ptdescs hexagon: Convert __pte_free_tlb() to use ptdescs loongarch: Convert various functions to use ptdescs m68k: Convert various functions to use ptdescs mips: Convert various functions to use ptdescs nios2: Convert __pte_free_tlb() to use ptdescs openrisc: Convert __pte_free_tlb() to use ptdescs riscv: Convert alloc_{pmd, pte}_late() to use ptdescs sh: Convert pte_free_tlb() to use ptdescs sparc64: Convert various functions to use ptdescs sparc: Convert pgtable_pte_page_{ctor, dtor}() to ptdesc equivalents um: Convert {pmd, pte}_free_tlb() to use ptdescs mm: Remove pgtable_{pmd, pte}_page_{ctor, dtor}() wrappers Documentation/mm/split_page_table_lock.rst | 12 +- .../zh_CN/mm/split_page_table_lock.rst | 14 +- arch/arm/include/asm/tlb.h | 12 +- arch/arm/mm/mmu.c | 7 +- arch/arm64/include/asm/tlb.h | 14 +- arch/arm64/mm/mmu.c | 7 +- arch/csky/include/asm/pgalloc.h | 4 +- arch/hexagon/include/asm/pgalloc.h | 8 +- arch/loongarch/include/asm/pgalloc.h | 27 ++- arch/loongarch/mm/pgtable.c | 7 +- arch/m68k/include/asm/mcf_pgalloc.h | 47 ++-- arch/m68k/include/asm/sun3_pgalloc.h | 8 +- arch/m68k/mm/motorola.c | 4 +- arch/mips/include/asm/pgalloc.h | 32 +-- arch/mips/mm/pgtable.c | 8 +- arch/nios2/include/asm/pgalloc.h | 8 +- arch/openrisc/include/asm/pgalloc.h | 8 +- arch/powerpc/mm/book3s64/mmu_context.c | 10 +- arch/powerpc/mm/book3s64/pgtable.c | 32 +-- arch/powerpc/mm/pgtable-frag.c | 46 ++-- arch/riscv/include/asm/pgalloc.h | 8 +- arch/riscv/mm/init.c | 16 +- arch/s390/include/asm/pgalloc.h | 4 +- arch/s390/include/asm/tlb.h | 4 +- arch/s390/mm/gmap.c | 207 ++++++++++-------- arch/s390/mm/pgalloc.c | 108 ++++----- arch/sh/include/asm/pgalloc.h | 9 +- arch/sparc/mm/init_64.c | 17 +- arch/sparc/mm/srmmu.c | 5 +- arch/um/include/asm/pgalloc.h | 18 +- arch/x86/mm/pgtable.c | 47 ++-- arch/x86/xen/mmu_pv.c | 2 +- include/asm-generic/pgalloc.h | 88 +++++--- include/asm-generic/tlb.h | 11 + include/linux/mm.h | 153 +++++++++---- include/linux/mm_types.h | 14 -- include/linux/page-flags.h | 30 ++- include/linux/pgtable.h | 77 +++++++ mm/memory.c | 8 +- 39 files changed, 686 insertions(+), 455 deletions(-) -- 2.40.1