From 800d8c63b2e989c2e349632d1648119bf5862f01 Mon Sep 17 00:00:00 2001 From: Kirill A. Shutemov Date: Tue, 26 Jul 2016 15:26:18 -0700 Subject: shmem: add huge pages support Here's basic implementation of huge pages support for shmem/tmpfs. It's all pretty streight-forward: - shmem_getpage() allcoates huge page if it can and try to inserd into radix tree with shmem_add_to_page_cache(); - shmem_add_to_page_cache() puts the page onto radix-tree if there's space for it; - shmem_undo_range() removes huge pages, if it fully within range. Partial truncate of huge pages zero out this part of THP. This have visible effect on fallocate(FALLOC_FL_PUNCH_HOLE) behaviour. As we don't really create hole in this case, lseek(SEEK_HOLE) may have inconsistent results depending what pages happened to be allocated. - no need to change shmem_fault: core-mm will map an compound page as huge if VMA is suitable; Link: http://lkml.kernel.org/r/1466021202-61880-30-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page-writeback.c | 1 + 1 file changed, 1 insertion(+) (limited to 'mm/page-writeback.c') diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 8195eb454411..d578d2a56b19 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2563,6 +2563,7 @@ int set_page_dirty(struct page *page) { struct address_space *mapping = page_mapping(page); + page = compound_head(page); if (likely(mapping)) { int (*spd)(struct page *) = mapping->a_ops->set_page_dirty; /* -- cgit v1.2.3-55-g7522