The patch titled Subject: m68k/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE has been added to the -mm mm-unstable branch. Its filename is m68k-mm-support-__have_arch_pte_swp_exclusive.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/m68k-mm-support-__have_arch_pte_swp_exclusive.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: David Hildenbrand <david@xxxxxxxxxx> Subject: m68k/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE Date: Fri, 13 Jan 2023 18:10:10 +0100 Let's support __HAVE_ARCH_PTE_SWP_EXCLUSIVE by stealing one bit from the type. Generic MM currently only uses 5 bits for the type (MAX_SWAPFILES_SHIFT), so the stolen bit is effectively unused. While at it, make sure for sun3 that the valid bit never gets set by properly masking it off and mask the type in __swp_entry(). Link: https://lkml.kernel.org/r/20230113171026.582290-11-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Cc: Greg Ungerer <gerg@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- --- a/arch/m68k/include/asm/mcf_pgtable.h~m68k-mm-support-__have_arch_pte_swp_exclusive +++ a/arch/m68k/include/asm/mcf_pgtable.h @@ -46,6 +46,9 @@ #define _CACHEMASK040 (~0x060) #define _PAGE_GLOBAL040 0x400 /* 68040 global bit, used for kva descs */ +/* We borrow bit 7 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE 0x080 + /* * Externally used page protection values. */ @@ -254,15 +257,42 @@ static inline pte_t pte_mkcache(pte_t pt extern pgd_t kernel_pg_dir[PTRS_PER_PGD]; /* - * Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e)) + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). + * + * Format of swap PTEs: + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * <------------------ offset -------------> 0 0 0 E <-- type ---> + * + * E is the exclusive marker that is not stored in swap entries. */ -#define __swp_type(x) ((x).val & 0xFF) +#define __swp_type(x) ((x).val & 0x7f) #define __swp_offset(x) ((x).val >> 11) -#define __swp_entry(typ, off) ((swp_entry_t) { (typ) | \ +#define __swp_entry(typ, off) ((swp_entry_t) { ((typ) & 0x7f) | \ (off << 11) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) #define __swp_entry_to_pte(x) (__pte((x).val)) +#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE +static inline int pte_swp_exclusive(pte_t pte) +{ + return pte_val(pte) & _PAGE_SWP_EXCLUSIVE; +} + +static inline pte_t pte_swp_mkexclusive(pte_t pte) +{ + pte_val(pte) |= _PAGE_SWP_EXCLUSIVE; + return pte; +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE; + return pte; +} + #define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT) #define pmd_page(pmd) (pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)) --- a/arch/m68k/include/asm/motorola_pgtable.h~m68k-mm-support-__have_arch_pte_swp_exclusive +++ a/arch/m68k/include/asm/motorola_pgtable.h @@ -41,6 +41,9 @@ #define _PAGE_PROTNONE 0x004 +/* We borrow bit 11 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE 0x800 + #ifndef __ASSEMBLY__ /* This is the cache mode to be used for pages containing page descriptors for @@ -169,12 +172,41 @@ static inline pte_t pte_mkcache(pte_t pt #define swapper_pg_dir kernel_pg_dir extern pgd_t kernel_pg_dir[128]; -/* Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e)) */ -#define __swp_type(x) (((x).val >> 4) & 0xff) +/* + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). + * + * Format of swap PTEs: + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * <----------------- offset ------------> E <-- type ---> 0 0 0 0 + * + * E is the exclusive marker that is not stored in swap entries. + */ +#define __swp_type(x) (((x).val >> 4) & 0x7f) #define __swp_offset(x) ((x).val >> 12) -#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 4) | ((offset) << 12) }) +#define __swp_entry(type, offset) ((swp_entry_t) { (((type) & 0x7f) << 4) | ((offset) << 12) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) +#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE +static inline int pte_swp_exclusive(pte_t pte) +{ + return pte_val(pte) & _PAGE_SWP_EXCLUSIVE; +} + +static inline pte_t pte_swp_mkexclusive(pte_t pte) +{ + pte_val(pte) |= _PAGE_SWP_EXCLUSIVE; + return pte; +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE; + return pte; +} + #endif /* !__ASSEMBLY__ */ #endif /* _MOTOROLA_PGTABLE_H */ --- a/arch/m68k/include/asm/sun3_pgtable.h~m68k-mm-support-__have_arch_pte_swp_exclusive +++ a/arch/m68k/include/asm/sun3_pgtable.h @@ -71,6 +71,9 @@ #define SUN3_PMD_MASK (0x0000003F) #define SUN3_PMD_MAGIC (0x0000002B) +/* We borrow bit 6 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE 0x040 + #ifndef __ASSEMBLY__ /* @@ -152,12 +155,42 @@ static inline pte_t pte_mkcache(pte_t pt extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; extern pgd_t kernel_pg_dir[PTRS_PER_PGD]; -/* Macros to (de)construct the fake PTEs representing swap pages. */ -#define __swp_type(x) ((x).val & 0x7F) +/* + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). + * + * Format of swap PTEs: + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * 0 <--------------------- offset ----------------> E <- type --> + * + * E is the exclusive marker that is not stored in swap entries. + */ +#define __swp_type(x) ((x).val & 0x3f) #define __swp_offset(x) (((x).val) >> 7) -#define __swp_entry(type,offset) ((swp_entry_t) { ((type) | ((offset) << 7)) }) +#define __swp_entry(type, offset) ((swp_entry_t) { (((type) & 0x3f) | \ + (((offset) << 7) & ~SUN3_PAGE_VALID)) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) #define __swp_entry_to_pte(x) ((pte_t) { (x).val }) +#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE +static inline int pte_swp_exclusive(pte_t pte) +{ + return pte_val(pte) & _PAGE_SWP_EXCLUSIVE; +} + +static inline pte_t pte_swp_mkexclusive(pte_t pte) +{ + pte_val(pte) |= _PAGE_SWP_EXCLUSIVE; + return pte; +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE; + return pte; +} + #endif /* !__ASSEMBLY__ */ #endif /* !_SUN3_PGTABLE_H */ _ Patches currently in -mm which might be from david@xxxxxxxxxx are mm-userfaultfd-rely-on-vma-vm_page_prot-in-uffd_wp_range.patch mm-userfaultfd-rely-on-vma-vm_page_prot-in-uffd_wp_range-fix.patch mm-mprotect-drop-pgprot_t-parameter-from-change_protection.patch mm-mprotect-drop-pgprot_t-parameter-from-change_protection-fix.patch selftests-vm-cow-add-cow-tests-for-collapsing-of-pte-mapped-anon-thp.patch mm-nommu-factor-out-check-for-nommu-shared-mappings-into-is_nommu_shared_mapping.patch mm-nommu-dont-use-vm_mayshare-for-map_private-mappings.patch drivers-misc-open-dice-dont-touch-vm_mayshare.patch selftests-mm-define-madv_pageout-to-fix-compilation-issues.patch mm-debug_vm_pgtable-more-pte_swp_exclusive-sanity-checks.patch alpha-mm-support-__have_arch_pte_swp_exclusive.patch arc-mm-support-__have_arch_pte_swp_exclusive.patch arm-mm-support-__have_arch_pte_swp_exclusive.patch csky-mm-support-__have_arch_pte_swp_exclusive.patch hexagon-mm-support-__have_arch_pte_swp_exclusive.patch ia64-mm-support-__have_arch_pte_swp_exclusive.patch loongarch-mm-support-__have_arch_pte_swp_exclusive.patch m68k-mm-remove-dummy-__swp-definitions-for-nommu.patch m68k-mm-support-__have_arch_pte_swp_exclusive.patch microblaze-mm-support-__have_arch_pte_swp_exclusive.patch mips-mm-support-__have_arch_pte_swp_exclusive.patch nios2-mm-refactor-swap-pte-layout.patch nios2-mm-support-__have_arch_pte_swp_exclusive.patch openrisc-mm-support-__have_arch_pte_swp_exclusive.patch parisc-mm-support-__have_arch_pte_swp_exclusive.patch powerpc-mm-support-__have_arch_pte_swp_exclusive-on-32bit-book3s.patch powerpc-nohash-mm-support-__have_arch_pte_swp_exclusive.patch riscv-mm-support-__have_arch_pte_swp_exclusive.patch sh-mm-support-__have_arch_pte_swp_exclusive.patch sparc-mm-support-__have_arch_pte_swp_exclusive-on-32bit.patch sparc-mm-support-__have_arch_pte_swp_exclusive-on-64bit.patch um-mm-support-__have_arch_pte_swp_exclusive.patch x86-mm-support-__have_arch_pte_swp_exclusive-also-on-32bit.patch xtensa-mm-support-__have_arch_pte_swp_exclusive.patch mm-remove-__have_arch_pte_swp_exclusive.patch