DAX was the only thing that created pmd_devmap and pud_devmap entries however it no longer does as DAX pages are now refcounted normally and pXd_trans_huge() returns true for those. Therefore checking both pXd_devmap and pXd_trans_huge() is redundant and the former can be removed without changing behaviour as it will always be false.
Signed-off-by: Alistair Popple <apop...@nvidia.com> --- fs/dax.c | 5 ++--- include/linux/huge_mm.h | 10 ++++------ include/linux/pgtable.h | 2 +- mm/hmm.c | 4 ++-- mm/huge_memory.c | 30 +++++++++--------------------- mm/mapping_dirty_helpers.c | 4 ++-- mm/memory.c | 15 ++++++--------- mm/migrate_device.c | 2 +- mm/mprotect.c | 2 +- mm/mremap.c | 5 ++--- mm/page_vma_mapped.c | 5 ++--- mm/pagewalk.c | 8 +++----- mm/pgtable-generic.c | 7 +++---- mm/userfaultfd.c | 4 ++-- mm/vmscan.c | 3 --- 15 files changed, 40 insertions(+), 66 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index 6763034..206dbd0 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1938,7 +1938,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp, * the PTE we need to set up. If so just return and the fault will be * retried. */ - if (pmd_trans_huge(*vmf->pmd) || pmd_devmap(*vmf->pmd)) { + if (pmd_trans_huge(*vmf->pmd)) { ret = VM_FAULT_NOPAGE; goto unlock_entry; } @@ -2061,8 +2061,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp, * the PMD we need to set up. If so just return and the fault will be * retried. */ - if (!pmd_none(*vmf->pmd) && !pmd_trans_huge(*vmf->pmd) && - !pmd_devmap(*vmf->pmd)) { + if (!pmd_none(*vmf->pmd) && !pmd_trans_huge(*vmf->pmd)) { ret = 0; goto unlock_entry; } diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index c0b01d1..374daa8 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -400,8 +400,7 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, #define split_huge_pmd(__vma, __pmd, __address) \ do { \ pmd_t *____pmd = (__pmd); \ - if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd) \ - || pmd_devmap(*____pmd)) \ + if (is_swap_pmd(*____pmd) || pmd_trans_huge(*____pmd)) \ __split_huge_pmd(__vma, __pmd, __address, \ false, NULL); \ } while (0) @@ -427,8 +426,7 @@ change_huge_pud(struct mmu_gather *tlb, struct vm_area_struct *vma, #define split_huge_pud(__vma, __pud, __address) \ do { \ pud_t *____pud = (__pud); \ - if (pud_trans_huge(*____pud) \ - || pud_devmap(*____pud)) \ + if (pud_trans_huge(*____pud)) \ __split_huge_pud(__vma, __pud, __address); \ } while (0) @@ -451,7 +449,7 @@ static inline int is_swap_pmd(pmd_t pmd) static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma) { - if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) + if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd)) return __pmd_trans_huge_lock(pmd, vma); else return NULL; @@ -459,7 +457,7 @@ static inline spinlock_t *pmd_trans_huge_lock(pmd_t *pmd, static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, struct vm_area_struct *vma) { - if (pud_trans_huge(*pud) || pud_devmap(*pud)) + if (pud_trans_huge(*pud)) return __pud_trans_huge_lock(pud, vma); else return NULL; diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index b50447e..a6f9573 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1656,7 +1656,7 @@ static inline int pud_trans_unstable(pud_t *pud) defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) pud_t pudval = READ_ONCE(*pud); - if (pud_none(pudval) || pud_trans_huge(pudval) || pud_devmap(pudval)) + if (pud_none(pudval) || pud_trans_huge(pudval)) return 1; if (unlikely(pud_bad(pudval))) { pud_clear_bad(pud); diff --git a/mm/hmm.c b/mm/hmm.c index 9e43008..5037f98 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -348,7 +348,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp, return hmm_pfns_fill(start, end, range, HMM_PFN_ERROR); } - if (pmd_devmap(pmd) || pmd_trans_huge(pmd)) { + if (pmd_trans_huge(pmd)) { /* * No need to take pmd_lock here, even if some other thread * is splitting the huge pmd we will get that event through @@ -359,7 +359,7 @@ static int hmm_vma_walk_pmd(pmd_t *pmdp, * values. */ pmd = pmdp_get_lockless(pmdp); - if (!pmd_devmap(pmd) && !pmd_trans_huge(pmd)) + if (!pmd_trans_huge(pmd)) goto again; return hmm_vma_handle_pmd(walk, addr, end, hmm_pfns, pmd); diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8d9d706..31b4110 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1398,10 +1398,7 @@ static int insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr, } entry = pmd_mkhuge(pfn_t_pmd(pfn, prot)); - if (pfn_t_devmap(pfn)) - entry = pmd_mkdevmap(entry); - else - entry = pmd_mkspecial(entry); + entry = pmd_mkspecial(entry); if (write) { entry = pmd_mkyoung(pmd_mkdirty(entry)); entry = maybe_pmd_mkwrite(entry, vma); @@ -1441,8 +1438,6 @@ vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write) * but we need to be consistent with PTEs and architectures that * can't support a 'special' bit. */ - BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) && - !pfn_t_devmap(pfn)); BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) == (VM_PFNMAP|VM_MIXEDMAP)); BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags)); @@ -1535,10 +1530,7 @@ static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, } entry = pud_mkhuge(pfn_t_pud(pfn, prot)); - if (pfn_t_devmap(pfn)) - entry = pud_mkdevmap(entry); - else - entry = pud_mkspecial(entry); + entry = pud_mkspecial(entry); if (write) { entry = pud_mkyoung(pud_mkdirty(entry)); entry = maybe_pud_mkwrite(entry, vma); @@ -1569,8 +1561,6 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write) * but we need to be consistent with PTEs and architectures that * can't support a 'special' bit. */ - BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) && - !pfn_t_devmap(pfn)); BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) == (VM_PFNMAP|VM_MIXEDMAP)); BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags)); @@ -1797,7 +1787,7 @@ int copy_huge_pud(struct mm_struct *dst_mm, struct mm_struct *src_mm, ret = -EAGAIN; pud = *src_pud; - if (unlikely(!pud_trans_huge(pud) && !pud_devmap(pud))) + if (unlikely(!pud_trans_huge(pud))) goto out_unlock; /* @@ -2651,8 +2641,7 @@ spinlock_t *__pmd_trans_huge_lock(pmd_t *pmd, struct vm_area_struct *vma) { spinlock_t *ptl; ptl = pmd_lock(vma->vm_mm, pmd); - if (likely(is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || - pmd_devmap(*pmd))) + if (likely(is_swap_pmd(*pmd) || pmd_trans_huge(*pmd))) return ptl; spin_unlock(ptl); return NULL; @@ -2669,7 +2658,7 @@ spinlock_t *__pud_trans_huge_lock(pud_t *pud, struct vm_area_struct *vma) spinlock_t *ptl; ptl = pud_lock(vma->vm_mm, pud); - if (likely(pud_trans_huge(*pud) || pud_devmap(*pud))) + if (likely(pud_trans_huge(*pud))) return ptl; spin_unlock(ptl); return NULL; @@ -2721,7 +2710,7 @@ static void __split_huge_pud_locked(struct vm_area_struct *vma, pud_t *pud, VM_BUG_ON(haddr & ~HPAGE_PUD_MASK); VM_BUG_ON_VMA(vma->vm_start > haddr, vma); VM_BUG_ON_VMA(vma->vm_end < haddr + HPAGE_PUD_SIZE, vma); - VM_BUG_ON(!pud_trans_huge(*pud) && !pud_devmap(*pud)); + VM_BUG_ON(!pud_trans_huge(*pud)); count_vm_event(THP_SPLIT_PUD); @@ -2754,7 +2743,7 @@ void __split_huge_pud(struct vm_area_struct *vma, pud_t *pud, (address & HPAGE_PUD_MASK) + HPAGE_PUD_SIZE); mmu_notifier_invalidate_range_start(&range); ptl = pud_lock(vma->vm_mm, pud); - if (unlikely(!pud_trans_huge(*pud) && !pud_devmap(*pud))) + if (unlikely(!pud_trans_huge(*pud))) goto out; __split_huge_pud_locked(vma, pud, range.start); @@ -2827,8 +2816,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, VM_BUG_ON(haddr & ~HPAGE_PMD_MASK); VM_BUG_ON_VMA(vma->vm_start > haddr, vma); VM_BUG_ON_VMA(vma->vm_end < haddr + HPAGE_PMD_SIZE, vma); - VM_BUG_ON(!is_pmd_migration_entry(*pmd) && !pmd_trans_huge(*pmd) - && !pmd_devmap(*pmd)); + VM_BUG_ON(!is_pmd_migration_entry(*pmd) && !pmd_trans_huge(*pmd)); count_vm_event(THP_SPLIT_PMD); @@ -3047,7 +3035,7 @@ void split_huge_pmd_locked(struct vm_area_struct *vma, unsigned long address, * require a folio to check the PMD against. Otherwise, there * is a risk of replacing the wrong folio. */ - if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd) || pmd_migration) { + if (pmd_trans_huge(*pmd) || pmd_migration) { /* * Do not apply pmd_folio() to a migration entry; and folio lock * guarantees that it must be of the wrong folio anyway. diff --git a/mm/mapping_dirty_helpers.c b/mm/mapping_dirty_helpers.c index 2f8829b..208b428 100644 --- a/mm/mapping_dirty_helpers.c +++ b/mm/mapping_dirty_helpers.c @@ -129,7 +129,7 @@ static int wp_clean_pmd_entry(pmd_t *pmd, unsigned long addr, unsigned long end, pmd_t pmdval = pmdp_get_lockless(pmd); /* Do not split a huge pmd, present or migrated */ - if (pmd_trans_huge(pmdval) || pmd_devmap(pmdval)) { + if (pmd_trans_huge(pmdval)) { WARN_ON(pmd_write(pmdval) || pmd_dirty(pmdval)); walk->action = ACTION_CONTINUE; } @@ -152,7 +152,7 @@ static int wp_clean_pud_entry(pud_t *pud, unsigned long addr, unsigned long end, pud_t pudval = READ_ONCE(*pud); /* Do not split a huge pud */ - if (pud_trans_huge(pudval) || pud_devmap(pudval)) { + if (pud_trans_huge(pudval)) { WARN_ON(pud_write(pudval) || pud_dirty(pudval)); walk->action = ACTION_CONTINUE; } diff --git a/mm/memory.c b/mm/memory.c index 7a9aaae..6b03771 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -663,8 +663,6 @@ struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr, } } - if (pmd_devmap(pmd)) - return NULL; if (is_huge_zero_pmd(pmd)) return NULL; if (unlikely(pfn > highest_memmap_pfn)) @@ -1228,8 +1226,7 @@ copy_pmd_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma, src_pmd = pmd_offset(src_pud, addr); do { next = pmd_addr_end(addr, end); - if (is_swap_pmd(*src_pmd) || pmd_trans_huge(*src_pmd) - || pmd_devmap(*src_pmd)) { + if (is_swap_pmd(*src_pmd) || pmd_trans_huge(*src_pmd)) { int err; VM_BUG_ON_VMA(next-addr != HPAGE_PMD_SIZE, src_vma); err = copy_huge_pmd(dst_mm, src_mm, dst_pmd, src_pmd, @@ -1265,7 +1262,7 @@ copy_pud_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma, src_pud = pud_offset(src_p4d, addr); do { next = pud_addr_end(addr, end); - if (pud_trans_huge(*src_pud) || pud_devmap(*src_pud)) { + if (pud_trans_huge(*src_pud)) { int err; VM_BUG_ON_VMA(next-addr != HPAGE_PUD_SIZE, src_vma); @@ -1787,7 +1784,7 @@ static inline unsigned long zap_pmd_range(struct mmu_gather *tlb, pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); - if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd) || pmd_devmap(*pmd)) { + if (is_swap_pmd(*pmd) || pmd_trans_huge(*pmd)) { if (next - addr != HPAGE_PMD_SIZE) __split_huge_pmd(vma, pmd, addr, false, NULL); else if (zap_huge_pmd(tlb, vma, pmd, addr)) { @@ -1829,7 +1826,7 @@ static inline unsigned long zap_pud_range(struct mmu_gather *tlb, pud = pud_offset(p4d, addr); do { next = pud_addr_end(addr, end); - if (pud_trans_huge(*pud) || pud_devmap(*pud)) { + if (pud_trans_huge(*pud)) { if (next - addr != HPAGE_PUD_SIZE) { mmap_assert_locked(tlb->mm); split_huge_pud(vma, pud, addr); @@ -6062,7 +6059,7 @@ static vm_fault_t __handle_mm_fault(struct vm_area_struct *vma, pud_t orig_pud = *vmf.pud; barrier(); - if (pud_trans_huge(orig_pud) || pud_devmap(orig_pud)) { + if (pud_trans_huge(orig_pud)) { /* * TODO once we support anonymous PUDs: NUMA case and @@ -6103,7 +6100,7 @@ static vm_fault_t __handle_mm_fault(struct vm_area_struct *vma, pmd_migration_entry_wait(mm, vmf.pmd); return 0; } - if (pmd_trans_huge(vmf.orig_pmd) || pmd_devmap(vmf.orig_pmd)) { + if (pmd_trans_huge(vmf.orig_pmd)) { if (pmd_protnone(vmf.orig_pmd) && vma_is_accessible(vma)) return do_huge_pmd_numa_page(&vmf); diff --git a/mm/migrate_device.c b/mm/migrate_device.c index 3158afe..e05e14d 100644 --- a/mm/migrate_device.c +++ b/mm/migrate_device.c @@ -615,7 +615,7 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate, pmdp = pmd_alloc(mm, pudp, addr); if (!pmdp) goto abort; - if (pmd_trans_huge(*pmdp) || pmd_devmap(*pmdp)) + if (pmd_trans_huge(*pmdp)) goto abort; if (pte_alloc(mm, pmdp)) goto abort; diff --git a/mm/mprotect.c b/mm/mprotect.c index 62c1f79..dbf49c8 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -376,7 +376,7 @@ static inline long change_pmd_range(struct mmu_gather *tlb, goto next; _pmd = pmdp_get_lockless(pmd); - if (is_swap_pmd(_pmd) || pmd_trans_huge(_pmd) || pmd_devmap(_pmd)) { + if (is_swap_pmd(_pmd) || pmd_trans_huge(_pmd)) { if ((next - addr != HPAGE_PMD_SIZE) || pgtable_split_needed(vma, cp_flags)) { __split_huge_pmd(vma, pmd, addr, false, NULL); diff --git a/mm/mremap.c b/mm/mremap.c index 7db9da6..bcebfda 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -792,7 +792,7 @@ unsigned long move_page_tables(struct pagetable_move_control *pmc) new_pud = alloc_new_pud(mm, pmc->new_addr); if (!new_pud) break; - if (pud_trans_huge(*old_pud) || pud_devmap(*old_pud)) { + if (pud_trans_huge(*old_pud)) { if (extent == HPAGE_PUD_SIZE) { move_pgt_entry(pmc, HPAGE_PUD, old_pud, new_pud); /* We ignore and continue on error? */ @@ -811,8 +811,7 @@ unsigned long move_page_tables(struct pagetable_move_control *pmc) if (!new_pmd) break; again: - if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd) || - pmd_devmap(*old_pmd)) { + if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd)) { if (extent == HPAGE_PMD_SIZE && move_pgt_entry(pmc, HPAGE_PMD, old_pmd, new_pmd)) continue; diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index e463c3b..e981a1a 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -246,8 +246,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) */ pmde = pmdp_get_lockless(pvmw->pmd); - if (pmd_trans_huge(pmde) || is_pmd_migration_entry(pmde) || - (pmd_present(pmde) && pmd_devmap(pmde))) { + if (pmd_trans_huge(pmde) || is_pmd_migration_entry(pmde)) { pvmw->ptl = pmd_lock(mm, pvmw->pmd); pmde = *pvmw->pmd; if (!pmd_present(pmde)) { @@ -262,7 +261,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) return not_found(pvmw); return true; } - if (likely(pmd_trans_huge(pmde) || pmd_devmap(pmde))) { + if (likely(pmd_trans_huge(pmde))) { if (pvmw->flags & PVMW_MIGRATION) return not_found(pvmw); if (!check_pmd(pmd_pfn(pmde), pvmw)) diff --git a/mm/pagewalk.c b/mm/pagewalk.c index 0dfb9c2..cca170f 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -143,8 +143,7 @@ static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, * We are ONLY installing, so avoid unnecessarily * splitting a present huge page. */ - if (pmd_present(*pmd) && - (pmd_trans_huge(*pmd) || pmd_devmap(*pmd))) + if (pmd_present(*pmd) && pmd_trans_huge(*pmd)) continue; } @@ -210,8 +209,7 @@ static int walk_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end, * We are ONLY installing, so avoid unnecessarily * splitting a present huge page. */ - if (pud_present(*pud) && - (pud_trans_huge(*pud) || pud_devmap(*pud))) + if (pud_present(*pud) && pud_trans_huge(*pud)) continue; } @@ -872,7 +870,7 @@ struct folio *folio_walk_start(struct folio_walk *fw, * TODO: FW_MIGRATION support for PUD migration entries * once there are relevant users. */ - if (!pud_present(pud) || pud_devmap(pud) || pud_special(pud)) { + if (!pud_present(pud) || pud_special(pud)) { spin_unlock(ptl); goto not_found; } else if (!pud_leaf(pud)) { diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c index 5a882f2..567e2d0 100644 --- a/mm/pgtable-generic.c +++ b/mm/pgtable-generic.c @@ -139,8 +139,7 @@ pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address, { pmd_t pmd; VM_BUG_ON(address & ~HPAGE_PMD_MASK); - VM_BUG_ON(pmd_present(*pmdp) && !pmd_trans_huge(*pmdp) && - !pmd_devmap(*pmdp)); + VM_BUG_ON(pmd_present(*pmdp) && !pmd_trans_huge(*pmdp)); pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp); flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); return pmd; @@ -153,7 +152,7 @@ pud_t pudp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address, pud_t pud; VM_BUG_ON(address & ~HPAGE_PUD_MASK); - VM_BUG_ON(!pud_trans_huge(*pudp) && !pud_devmap(*pudp)); + VM_BUG_ON(!pud_trans_huge(*pudp)); pud = pudp_huge_get_and_clear(vma->vm_mm, address, pudp); flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE); return pud; @@ -293,7 +292,7 @@ pte_t *___pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp) *pmdvalp = pmdval; if (unlikely(pmd_none(pmdval) || is_pmd_migration_entry(pmdval))) goto nomap; - if (unlikely(pmd_trans_huge(pmdval) || pmd_devmap(pmdval))) + if (unlikely(pmd_trans_huge(pmdval))) goto nomap; if (unlikely(pmd_bad(pmdval))) { pmd_clear_bad(pmd); diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 133f750..7669f4b 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -795,8 +795,8 @@ static __always_inline ssize_t mfill_atomic(struct userfaultfd_ctx *ctx, * (This includes the case where the PMD used to be THP and * changed back to none after __pte_alloc().) */ - if (unlikely(!pmd_present(dst_pmdval) || pmd_trans_huge(dst_pmdval) || - pmd_devmap(dst_pmdval))) { + if (unlikely(!pmd_present(dst_pmdval) || + pmd_trans_huge(dst_pmdval))) { err = -EEXIST; break; } diff --git a/mm/vmscan.c b/mm/vmscan.c index 61e6c44..8bf62b1 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3426,9 +3426,6 @@ static unsigned long get_pmd_pfn(pmd_t pmd, struct vm_area_struct *vma, unsigned if (!pmd_present(pmd) || is_huge_zero_pmd(pmd)) return -1; - if (WARN_ON_ONCE(pmd_devmap(pmd))) - return -1; - if (!pmd_young(pmd) && !mm_has_notifiers(vma->vm_mm)) return -1; -- git-series 0.9.1