HWPOISON: Use bitmask/action code for try_to_unmap behaviour

[deliverable/linux.git] / mm / rmap.c

diff --git a/mm/rmap.c b/mm/rmap.c
index 5a35c030e7793d22fa769a6815c587533ac1093c..08c112a776a7811517b2d7bcb3e27c9386b3b35b 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -774,7 +774,7 @@ void page_remove_rmap(struct page *page)
  * repeatedly from either try_to_unmap_anon or try_to_unmap_file.
  */
 static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
-                               int migration)
+                               enum ttu_flags flags)
 {
        struct mm_struct *mm = vma->vm_mm;
        unsigned long address;
@@ -796,11 +796,13 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
         * If it's recently referenced (perhaps page_referenced
         * skipped over this mm) then we should reactivate it.
         */
-       if (!migration) {
+       if (!(flags & TTU_IGNORE_MLOCK)) {
                if (vma->vm_flags & VM_LOCKED) {
                        ret = SWAP_MLOCK;
                        goto out_unmap;
                }
+       }
+       if (!(flags & TTU_IGNORE_ACCESS)) {
                if (ptep_clear_flush_young_notify(vma, address, pte)) {
                        ret = SWAP_FAIL;
                        goto out_unmap;
@@ -840,12 +842,12 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
                         * pte. do_swap_page() will wait until the migration
                         * pte is removed and then restart fault handling.
                         */
-                       BUG_ON(!migration);
+                       BUG_ON(TTU_ACTION(flags) != TTU_MIGRATION);
                        entry = make_migration_entry(page, pte_write(pteval));
                }
                set_pte_at(mm, address, pte, swp_entry_to_pte(entry));
                BUG_ON(pte_file(*pte));
-       } else if (PAGE_MIGRATION && migration) {
+       } else if (PAGE_MIGRATION && (TTU_ACTION(flags) == TTU_MIGRATION)) {
                /* Establish migration entry for a file page */
                swp_entry_t entry;
                entry = make_migration_entry(page, pte_write(pteval));
@@ -1014,12 +1016,13 @@ static int try_to_mlock_page(struct page *page, struct vm_area_struct *vma)
  * vm_flags for that VMA.  That should be OK, because that vma shouldn't be
  * 'LOCKED.
  */
-static int try_to_unmap_anon(struct page *page, int unlock, int migration)
+static int try_to_unmap_anon(struct page *page, enum ttu_flags flags)
 {
        struct anon_vma *anon_vma;
        struct vm_area_struct *vma;
        unsigned int mlocked = 0;
        int ret = SWAP_AGAIN;
+       int unlock = TTU_ACTION(flags) == TTU_MUNLOCK;
 
        if (MLOCK_PAGES && unlikely(unlock))
                ret = SWAP_SUCCESS;     /* default for try_to_munlock() */
@@ -1035,7 +1038,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration)
                                continue;  /* must visit all unlocked vmas */
                        ret = SWAP_MLOCK;  /* saw at least one mlocked vma */
                } else {
-                       ret = try_to_unmap_one(page, vma, migration);
+                       ret = try_to_unmap_one(page, vma, flags);
                        if (ret == SWAP_FAIL || !page_mapped(page))
                                break;
                }
@@ -1059,8 +1062,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration)
 /**
  * try_to_unmap_file - unmap/unlock file page using the object-based rmap method
  * @page: the page to unmap/unlock
- * @unlock:  request for unlock rather than unmap [unlikely]
- * @migration:  unmapping for migration - ignored if @unlock
+ * @flags: action and flags
  *
  * Find all the mappings of a page using the mapping pointer and the vma chains
  * contained in the address_space struct it points to.
@@ -1072,7 +1074,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration)
  * vm_flags for that VMA.  That should be OK, because that vma shouldn't be
  * 'LOCKED.
  */
-static int try_to_unmap_file(struct page *page, int unlock, int migration)
+static int try_to_unmap_file(struct page *page, enum ttu_flags flags)
 {
        struct address_space *mapping = page->mapping;
        pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
@@ -1084,6 +1086,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration)
        unsigned long max_nl_size = 0;
        unsigned int mapcount;
        unsigned int mlocked = 0;
+       int unlock = TTU_ACTION(flags) == TTU_MUNLOCK;
 
        if (MLOCK_PAGES && unlikely(unlock))
                ret = SWAP_SUCCESS;     /* default for try_to_munlock() */
@@ -1096,7 +1099,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration)
                                continue;       /* must visit all vmas */
                        ret = SWAP_MLOCK;
                } else {
-                       ret = try_to_unmap_one(page, vma, migration);
+                       ret = try_to_unmap_one(page, vma, flags);
                        if (ret == SWAP_FAIL || !page_mapped(page))
                                goto out;
                }
@@ -1121,7 +1124,8 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration)
                        ret = SWAP_MLOCK;       /* leave mlocked == 0 */
                        goto out;               /* no need to look further */
                }
-               if (!MLOCK_PAGES && !migration && (vma->vm_flags & VM_LOCKED))
+               if (!MLOCK_PAGES && !(flags & TTU_IGNORE_MLOCK) &&
+                       (vma->vm_flags & VM_LOCKED))
                        continue;
                cursor = (unsigned long) vma->vm_private_data;
                if (cursor > max_nl_cursor)
@@ -1155,7 +1159,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration)
        do {
                list_for_each_entry(vma, &mapping->i_mmap_nonlinear,
                                                shared.vm_set.list) {
-                       if (!MLOCK_PAGES && !migration &&
+                       if (!MLOCK_PAGES && !(flags & TTU_IGNORE_MLOCK) &&
                            (vma->vm_flags & VM_LOCKED))
                                continue;
                        cursor = (unsigned long) vma->vm_private_data;
@@ -1195,7 +1199,7 @@ out:
 /**
  * try_to_unmap - try to remove all page table mappings to a page
  * @page: the page to get unmapped
- * @migration: migration flag
+ * @flags: action and flags
  *
  * Tries to remove all the page table entries which are mapping this
  * page, used in the pageout path.  Caller must hold the page lock.
@@ -1206,16 +1210,16 @@ out:
  * SWAP_FAIL   - the page is unswappable
  * SWAP_MLOCK  - page is mlocked.
  */
-int try_to_unmap(struct page *page, int migration)
+int try_to_unmap(struct page *page, enum ttu_flags flags)
 {
        int ret;
 
        BUG_ON(!PageLocked(page));
 
        if (PageAnon(page))
-               ret = try_to_unmap_anon(page, 0, migration);
+               ret = try_to_unmap_anon(page, flags);
        else
-               ret = try_to_unmap_file(page, 0, migration);
+               ret = try_to_unmap_file(page, flags);
        if (ret != SWAP_MLOCK && !page_mapped(page))
                ret = SWAP_SUCCESS;
        return ret;
@@ -1240,8 +1244,8 @@ int try_to_munlock(struct page *page)
        VM_BUG_ON(!PageLocked(page) || PageLRU(page));
 
        if (PageAnon(page))
-               return try_to_unmap_anon(page, 1, 0);
+               return try_to_unmap_anon(page, TTU_MUNLOCK);
        else
-               return try_to_unmap_file(page, 1, 0);
+               return try_to_unmap_file(page, TTU_MUNLOCK);
 }