hugetlbfs: fix alignment of huge page requests

When calling shmget() with SHM_HUGETLB, shmget aligns the request size to
PAGE_SIZE, but this is not sufficient.

Modify hugetlb_file_setup() to align requests to the huge page size, and
to accept an address argument so that all alignment checks can be
performed in hugetlb_file_setup(), rather than in its callers.  Change
newseg() and mmap_pgoff() to match the new prototype and eliminate a now
redundant alignment check.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Steven Truelove <steven.truelove@utoronto.ca>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index 9e0c0de2e7e3..a19cc271e794 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1099,9 +1099,9 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
                  * A dummy user value is used because we are not locking
                  * memory so no accounting is necessary
                  */
-                len = ALIGN(len, huge_page_size(&default_hstate));
-                file = hugetlb_file_setup(HUGETLB_ANON_FILE, len, VM_NORESERVE,
-                                                &user, HUGETLB_ANONHUGE_INODE);
+                file = hugetlb_file_setup(HUGETLB_ANON_FILE, addr, len,
+                                                VM_NORESERVE, &user,
+                                                HUGETLB_ANONHUGE_INODE);
                 if (IS_ERR(file))
                         return PTR_ERR(file);
         }