mm/damon/sysfs: eliminate potential uninitialized variable warning

[platform/kernel/linux-starfive.git] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index 582f531..f0a15ce 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3475,13 +3475,11 @@ skip:
  */
 static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
                        struct folio *folio, unsigned long start,
-                       unsigned long addr, unsigned int nr_pages)
+                       unsigned long addr, unsigned int nr_pages,
+                       unsigned int *mmap_miss)
 {
        vm_fault_t ret = 0;
-       struct vm_area_struct *vma = vmf->vma;
-       struct file *file = vma->vm_file;
        struct page *page = folio_page(folio, start);
-       unsigned int mmap_miss = READ_ONCE(file->f_ra.mmap_miss);
        unsigned int count = 0;
        pte_t *old_ptep = vmf->pte;
 
@@ -3489,8 +3487,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
                if (PageHWPoison(page + count))
                        goto skip;
 
-               if (mmap_miss > 0)
-                       mmap_miss--;
+               (*mmap_miss)++;
 
                /*
                 * NOTE: If there're PTE markers, we'll leave them to be
@@ -3506,7 +3503,7 @@ skip:
                if (count) {
                        set_pte_range(vmf, folio, page, count, addr);
                        folio_ref_add(folio, count);
-                       if (in_range(vmf->address, addr, count))
+                       if (in_range(vmf->address, addr, count * PAGE_SIZE))
                                ret = VM_FAULT_NOPAGE;
                }
 
@@ -3520,12 +3517,40 @@ skip:
        if (count) {
                set_pte_range(vmf, folio, page, count, addr);
                folio_ref_add(folio, count);
-               if (in_range(vmf->address, addr, count))
+               if (in_range(vmf->address, addr, count * PAGE_SIZE))
                        ret = VM_FAULT_NOPAGE;
        }
 
        vmf->pte = old_ptep;
-       WRITE_ONCE(file->f_ra.mmap_miss, mmap_miss);
+
+       return ret;
+}
+
+static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf,
+               struct folio *folio, unsigned long addr,
+               unsigned int *mmap_miss)
+{
+       vm_fault_t ret = 0;
+       struct page *page = &folio->page;
+
+       if (PageHWPoison(page))
+               return ret;
+
+       (*mmap_miss)++;
+
+       /*
+        * NOTE: If there're PTE markers, we'll leave them to be
+        * handled in the specific fault path, and it'll prohibit
+        * the fault-around logic.
+        */
+       if (!pte_none(ptep_get(vmf->pte)))
+               return ret;
+
+       if (vmf->address == addr)
+               ret = VM_FAULT_NOPAGE;
+
+       set_pte_range(vmf, folio, page, 1, addr);
+       folio_ref_inc(folio);
 
        return ret;
 }
@@ -3541,7 +3566,7 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
        XA_STATE(xas, &mapping->i_pages, start_pgoff);
        struct folio *folio;
        vm_fault_t ret = 0;
-       int nr_pages = 0;
+       unsigned int nr_pages = 0, mmap_miss = 0, mmap_miss_saved;
 
        rcu_read_lock();
        folio = next_uptodate_folio(&xas, mapping, end_pgoff);
@@ -3569,25 +3594,27 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf,
                end = folio->index + folio_nr_pages(folio) - 1;
                nr_pages = min(end, end_pgoff) - xas.xa_index + 1;
 
-               /*
-                * NOTE: If there're PTE markers, we'll leave them to be
-                * handled in the specific fault path, and it'll prohibit the
-                * fault-around logic.
-                */
-               if (!pte_none(ptep_get(vmf->pte)))
-                       goto unlock;
-
-               ret |= filemap_map_folio_range(vmf, folio,
-                               xas.xa_index - folio->index, addr, nr_pages);
+               if (!folio_test_large(folio))
+                       ret |= filemap_map_order0_folio(vmf,
+                                       folio, addr, &mmap_miss);
+               else
+                       ret |= filemap_map_folio_range(vmf, folio,
+                                       xas.xa_index - folio->index, addr,
+                                       nr_pages, &mmap_miss);
 
-unlock:
                folio_unlock(folio);
                folio_put(folio);
-               folio = next_uptodate_folio(&xas, mapping, end_pgoff);
-       } while (folio);
+       } while ((folio = next_uptodate_folio(&xas, mapping, end_pgoff)) != NULL);
        pte_unmap_unlock(vmf->pte, vmf->ptl);
 out:
        rcu_read_unlock();
+
+       mmap_miss_saved = READ_ONCE(file->f_ra.mmap_miss);
+       if (mmap_miss >= mmap_miss_saved)
+               WRITE_ONCE(file->f_ra.mmap_miss, 0);
+       else
+               WRITE_ONCE(file->f_ra.mmap_miss, mmap_miss_saved - mmap_miss);
+
        return ret;
 }
 EXPORT_SYMBOL(filemap_map_pages);