From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> If we starting position of truncation is in tail page we have to spilit the huge page page first. We also have to split if end is within the huge page. Otherwise we can truncate whole huge page at once. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> --- mm/truncate.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/mm/truncate.c b/mm/truncate.c index c75b736..87c247d 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -231,6 +231,17 @@ void truncate_inode_pages_range(struct address_space *mapping, if (index > end) break; + /* split page if we start from tail page */ + if (PageTransTail(page)) + split_huge_page(compound_trans_head(page)); + if (PageTransHuge(page)) { + /* split if end is within huge page */ + if (index == (end & ~HPAGE_CACHE_INDEX_MASK)) + split_huge_page(page); + else + /* skip tail pages */ + i += HPAGE_CACHE_NR - 1; + } if (!trylock_page(page)) continue; WARN_ON(page->index != index); @@ -280,6 +291,7 @@ void truncate_inode_pages_range(struct address_space *mapping, if (index > end) break; + VM_BUG_ON(PageTransHuge(page)); lock_page(page); WARN_ON(page->index != index); wait_on_page_writeback(page); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html