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Diffstat (limited to 'mm')
-rw-r--r--mm/internal.h18
-rw-r--r--mm/mmap.c2
-rw-r--r--mm/mprotect.c2
3 files changed, 20 insertions, 2 deletions
diff --git a/mm/internal.h b/mm/internal.h
index 899dab512c5a..caebaeb2e5c9 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -862,4 +862,22 @@ struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags);
DECLARE_PER_CPU(struct per_cpu_nodestat, boot_nodestats);
+static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma)
+{
+ /*
+ * NOTE: we must check this before VM_SOFTDIRTY on soft-dirty
+ * enablements, because when without soft-dirty being compiled in,
+ * VM_SOFTDIRTY is defined as 0x0, then !(vm_flags & VM_SOFTDIRTY)
+ * will be constantly true.
+ */
+ if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY))
+ return false;
+
+ /*
+ * Soft-dirty is kind of special: its tracking is enabled when the
+ * vma flags not set.
+ */
+ return !(vma->vm_flags & VM_SOFTDIRTY);
+}
+
#endif /* __MM_INTERNAL_H */
diff --git a/mm/mmap.c b/mm/mmap.c
index ec4e0d53a388..c035020d0c89 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1647,7 +1647,7 @@ int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot)
return 0;
/* Do we need to track softdirty? */
- if (IS_ENABLED(CONFIG_MEM_SOFT_DIRTY) && !(vm_flags & VM_SOFTDIRTY))
+ if (vma_soft_dirty_enabled(vma))
return 1;
/* Specialty mapping? */
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 8250c1315d9c..3a23dde73723 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -49,7 +49,7 @@ static inline bool can_change_pte_writable(struct vm_area_struct *vma,
return false;
/* Do we need write faults for softdirty tracking? */
- if ((vma->vm_flags & VM_SOFTDIRTY) && !pte_soft_dirty(pte))
+ if (vma_soft_dirty_enabled(vma) && !pte_soft_dirty(pte))
return false;
/* Do we need write faults for uffd-wp tracking? */