[PATCHv4 28/43] truncate: make invalidate_inode_pages2_range() aware about huge pages

[Kirill A. Shutemov]

For huge pages we need to unmap whole range covered by the huge page.

Signed-off-by: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
---
 mm/truncate.c | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/mm/truncate.c b/mm/truncate.c
index 7bb9d197a9e8..59bc1b4260d1 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -693,27 +693,34 @@ int invalidate_inode_pages2_range(struct address_space 
*mapping,
                                continue;
                        }
                        wait_on_page_writeback(page);
+                       page = compound_head(page);
+
                        if (page_mapped(page)) {
+                               loff_t begin, len;
+
+                               begin = page->index << PAGE_SHIFT;
+
                                if (!did_range_unmap) {
                                        /*
                                         * Zap the rest of the file in one hit.
                                         */
+                                       len = (loff_t)(1 + end - page->index) <<
+                                               PAGE_SHIFT;
+                                       if (len < hpage_size(page))
+                                               len = hpage_size(page);
                                        unmap_mapping_range(mapping,
-                                          (loff_t)index << PAGE_SHIFT,
-                                          (loff_t)(1 + end - index)
-                                                        << PAGE_SHIFT,
-                                                        0);
+                                                       begin, len, 0);
                                        did_range_unmap = 1;
                                } else {
                                        /*
                                         * Just zap this page
                                         */
-                                       unmap_mapping_range(mapping,
-                                          (loff_t)index << PAGE_SHIFT,
-                                          PAGE_SIZE, 0);
+                                       len = hpage_size(page);
+                                       unmap_mapping_range(mapping, begin,
+                                                       len, 0 );
                                }
                        }
-                       BUG_ON(page_mapped(page));
+                       VM_BUG_ON_PAGE(page_mapped(page), page);
                        ret2 = do_launder_page(mapping, page);
                        if (ret2 == 0) {
                                if (!invalidate_complete_page2(mapping, page))
@@ -722,6 +729,10 @@ int invalidate_inode_pages2_range(struct address_space 
*mapping,
                        if (ret2 < 0)
                                ret = ret2;
                        unlock_page(page);
+                       if (PageTransHuge(page)) {
+                               index = page->index + HPAGE_PMD_NR - 1;
+                               break;
+                       }
                }
                pagevec_remove_exceptionals(&pvec);
                pagevec_release(&pvec);
-- 
2.9.3