mm, madvise: move madvise_set_anon_name() down the file

Preparatory change so that we can use madvise_lock()/unlock() in the
function without forward declarations or more thorough shuffling.

No functional change.  Move as a separate commit helps git heuristics to
detect it properly.

Link: https://lkml.kernel.org/r/20250624-anon_name_cleanup-v2-3-600075462a11@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Colin Cross <ccross@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/madvise.c b/mm/madvise.c
index a2294bc1cc7bde965d49fde9f27e9a69936b9987..cb7d74d56debbd0e5b2664cd7acd1ddada01db23 100644 (file)
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -133,38 +133,6 @@ static int replace_anon_vma_name(struct vm_area_struct *vma,
 
        return 0;
 }
-
-static int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
-               unsigned long len_in, struct anon_vma_name *anon_name)
-{
-       unsigned long end;
-       unsigned long len;
-       struct madvise_behavior madv_behavior = {
-               .mm = mm,
-               .behavior = __MADV_SET_ANON_VMA_NAME,
-               .lock_mode = MADVISE_MMAP_WRITE_LOCK,
-               .anon_name = anon_name,
-       };
-
-       if (start & ~PAGE_MASK)
-               return -EINVAL;
-       len = (len_in + ~PAGE_MASK) & PAGE_MASK;
-
-       /* Check to see whether len was rounded up from small -ve to zero */
-       if (len_in && !len)
-               return -EINVAL;
-
-       end = start + len;
-       if (end < start)
-               return -EINVAL;
-
-       if (end == start)
-               return 0;
-
-       madv_behavior.range.start = start;
-       madv_behavior.range.end = end;
-       return madvise_walk_vmas(&madv_behavior);
-}
 #else /* CONFIG_ANON_VMA_NAME */
 static int replace_anon_vma_name(struct vm_area_struct *vma,
                                 struct anon_vma_name *anon_name)
@@ -2109,6 +2077,38 @@ static inline bool is_valid_name_char(char ch)
                !strchr(ANON_VMA_NAME_INVALID_CHARS, ch);
 }
 
+static int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
+               unsigned long len_in, struct anon_vma_name *anon_name)
+{
+       unsigned long end;
+       unsigned long len;
+       struct madvise_behavior madv_behavior = {
+               .mm = mm,
+               .behavior = __MADV_SET_ANON_VMA_NAME,
+               .lock_mode = MADVISE_MMAP_WRITE_LOCK,
+               .anon_name = anon_name,
+       };
+
+       if (start & ~PAGE_MASK)
+               return -EINVAL;
+       len = (len_in + ~PAGE_MASK) & PAGE_MASK;
+
+       /* Check to see whether len was rounded up from small -ve to zero */
+       if (len_in && !len)
+               return -EINVAL;
+
+       end = start + len;
+       if (end < start)
+               return -EINVAL;
+
+       if (end == start)
+               return 0;
+
+       madv_behavior.range.start = start;
+       madv_behavior.range.end = end;
+       return madvise_walk_vmas(&madv_behavior);
+}
+
 int set_anon_vma_name(unsigned long addr, unsigned long size,
                      const char __user *uname)
 {