diff options
| -rw-r--r-- | mm/huge_memory.c | 24 | ||||
| -rw-r--r-- | mm/rmap.c | 13 |
2 files changed, 27 insertions, 10 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index e7ac4f0dc21d..acb12653484e 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3063,8 +3063,12 @@ static bool __discard_anon_folio_pmd_locked(struct vm_area_struct *vma, int ref_count, map_count; pmd_t orig_pmd = *pmdp; - if (folio_test_dirty(folio) || pmd_dirty(orig_pmd)) + if (pmd_dirty(orig_pmd)) + folio_set_dirty(folio); + if (folio_test_dirty(folio) && !(vma->vm_flags & VM_DROPPABLE)) { + folio_set_swapbacked(folio); return false; + } orig_pmd = pmdp_huge_clear_flush(vma, addr, pmdp); @@ -3091,8 +3095,15 @@ static bool __discard_anon_folio_pmd_locked(struct vm_area_struct *vma, * * The only folio refs must be one from isolation plus the rmap(s). */ - if (folio_test_dirty(folio) || pmd_dirty(orig_pmd) || - ref_count != map_count + 1) { + if (pmd_dirty(orig_pmd)) + folio_set_dirty(folio); + if (folio_test_dirty(folio) && !(vma->vm_flags & VM_DROPPABLE)) { + folio_set_swapbacked(folio); + set_pmd_at(mm, addr, pmdp, orig_pmd); + return false; + } + + if (ref_count != map_count + 1) { set_pmd_at(mm, addr, pmdp, orig_pmd); return false; } @@ -3112,12 +3123,11 @@ bool unmap_huge_pmd_locked(struct vm_area_struct *vma, unsigned long addr, { VM_WARN_ON_FOLIO(!folio_test_pmd_mappable(folio), folio); VM_WARN_ON_FOLIO(!folio_test_locked(folio), folio); + VM_WARN_ON_FOLIO(!folio_test_anon(folio), folio); + VM_WARN_ON_FOLIO(folio_test_swapbacked(folio), folio); VM_WARN_ON_ONCE(!IS_ALIGNED(addr, HPAGE_PMD_SIZE)); - if (folio_test_anon(folio) && !folio_test_swapbacked(folio)) - return __discard_anon_folio_pmd_locked(vma, addr, pmdp, folio); - - return false; + return __discard_anon_folio_pmd_locked(vma, addr, pmdp, folio); } static void remap_page(struct folio *folio, unsigned long nr, int flags) diff --git a/mm/rmap.c b/mm/rmap.c index 7a93a7cd2c64..333ecac049b2 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1804,9 +1804,16 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, } if (!pvmw.pte) { - if (unmap_huge_pmd_locked(vma, pvmw.address, pvmw.pmd, - folio)) - goto walk_done; + if (folio_test_anon(folio) && !folio_test_swapbacked(folio)) { + if (unmap_huge_pmd_locked(vma, pvmw.address, pvmw.pmd, folio)) + goto walk_done; + /* + * unmap_huge_pmd_locked has either already marked + * the folio as swap-backed or decided to retain it + * due to GUP or speculative references. + */ + goto walk_abort; + } if (flags & TTU_SPLIT_HUGE_PMD) { /* |