Merge remote-tracking branch 'torvalds/master' into perf/core

[linux-2.6-microblaze.git] / mm / rmap.c

diff --git a/mm/rmap.c b/mm/rmap.c
index 693a610..e05c300 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -707,7 +707,6 @@ static bool should_defer_flush(struct mm_struct *mm, enum ttu_flags flags)
  */
 unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma)
 {
-       unsigned long address;
        if (PageAnon(page)) {
                struct anon_vma *page__anon_vma = page_anon_vma(page);
                /*
@@ -717,15 +716,13 @@ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma)
                if (!vma->anon_vma || !page__anon_vma ||
                    vma->anon_vma->root != page__anon_vma->root)
                        return -EFAULT;
-       } else if (page->mapping) {
-               if (!vma->vm_file || vma->vm_file->f_mapping != page->mapping)
-                       return -EFAULT;
-       } else
+       } else if (!vma->vm_file) {
                return -EFAULT;
-       address = __vma_address(page, vma);
-       if (unlikely(address < vma->vm_start || address >= vma->vm_end))
+       } else if (vma->vm_file->f_mapping != compound_head(page)->mapping) {
                return -EFAULT;
-       return address;
+       }
+
+       return vma_address(page, vma);
 }
 
 pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address)
@@ -919,7 +916,7 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma,
         */
        mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_PAGE,
                                0, vma, vma->vm_mm, address,
-                               min(vma->vm_end, address + page_size(page)));
+                               vma_address_end(page, vma));
        mmu_notifier_invalidate_range_start(&range);
 
        while (page_vma_mapped_walk(&pvmw)) {
@@ -1405,6 +1402,15 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
        struct mmu_notifier_range range;
        enum ttu_flags flags = (enum ttu_flags)(long)arg;
 
+       /*
+        * When racing against e.g. zap_pte_range() on another cpu,
+        * in between its ptep_get_and_clear_full() and page_remove_rmap(),
+        * try_to_unmap() may return false when it is about to become true,
+        * if page table locking is skipped: use TTU_SYNC to wait for that.
+        */
+       if (flags & TTU_SYNC)
+               pvmw.flags = PVMW_SYNC;
+
        /* munlock has nothing to gain from examining un-locked vmas */
        if ((flags & TTU_MUNLOCK) && !(vma->vm_flags & VM_LOCKED))
                return true;
@@ -1426,9 +1432,10 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
         * Note that the page can not be free in this function as call of
         * try_to_unmap() must hold a reference on the page.
         */
+       range.end = PageKsm(page) ?
+                       address + PAGE_SIZE : vma_address_end(page, vma);
        mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm,
-                               address,
-                               min(vma->vm_end, address + page_size(page)));
+                               address, range.end);
        if (PageHuge(page)) {
                /*
                 * If sharing is possible, start and end will be adjusted
@@ -1777,7 +1784,13 @@ bool try_to_unmap(struct page *page, enum ttu_flags flags)
        else
                rmap_walk(page, &rwc);
 
-       return !page_mapcount(page) ? true : false;
+       /*
+        * When racing against e.g. zap_pte_range() on another cpu,
+        * in between its ptep_get_and_clear_full() and page_remove_rmap(),
+        * try_to_unmap() may return false when it is about to become true,
+        * if page table locking is skipped: use TTU_SYNC to wait for that.
+        */
+       return !page_mapcount(page);
 }
 
 /**
@@ -1874,6 +1887,7 @@ static void rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
                struct vm_area_struct *vma = avc->vma;
                unsigned long address = vma_address(page, vma);
 
+               VM_BUG_ON_VMA(address == -EFAULT, vma);
                cond_resched();
 
                if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
@@ -1928,6 +1942,7 @@ static void rmap_walk_file(struct page *page, struct rmap_walk_control *rwc,
                        pgoff_start, pgoff_end) {
                unsigned long address = vma_address(page, vma);
 
+               VM_BUG_ON_VMA(address == -EFAULT, vma);
                cond_resched();
 
                if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))