From 493af578040e690f93f0fc8d9e7667ffff8155bb Mon Sep 17 00:00:00 2001 From: =?utf8?q?J=C3=B6rn=20Engel?= Date: Mon, 8 Jul 2013 16:00:26 -0700 Subject: [PATCH] mmap: allow MAP_HUGETLB for hugetlbfs files v2 It is counterintuitive at best that mmap'ing a hugetlbfs file with MAP_HUGETLB fails, while mmap'ing it without will a) succeed and b) return huge pages. v2: use is_file_hugepages(), as suggested by Jianguo Signed-off-by: Joern Engel Cc: Jianguo Wu Signed-off-by: Linus Torvalds --- mm/mmap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 8468ffd05bae..0718c175db8f 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1358,13 +1358,14 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, if (!(flags & MAP_ANONYMOUS)) { audit_mmap_fd(fd, flags); - if (unlikely(flags & MAP_HUGETLB)) - return -EINVAL; file = fget(fd); if (!file) goto out; if (is_file_hugepages(file)) len = ALIGN(len, huge_page_size(hstate_file(file))); + retval = -EINVAL; + if (unlikely(flags & MAP_HUGETLB && !is_file_hugepages(file))) + goto out_fput; } else if (flags & MAP_HUGETLB) { struct user_struct *user = NULL; struct hstate *hs = hstate_sizelog((flags >> MAP_HUGE_SHIFT) & @@ -1391,6 +1392,7 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE); retval = vm_mmap_pgoff(file, addr, len, prot, flags, pgoff); +out_fput: if (file) fput(file); out: -- 2.20.1