When calling shmget() with SHM_HUGETLB, shmget aligns the request size to PAGE_SIZE, but this is not sufficient. Modified hugetlb_file_setup() to align requests to the huge page size. Also modified mmap_pgoff() to avoid duplicating this check and to align against the start address. Signed-off-by: Steven Truelove <steven.truelove@xxxxxxxxxxx> --- fs/hugetlbfs/inode.c | 9 ++++++--- mm/mmap.c | 6 +++++- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 1e85a7a..b4bed46 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -938,6 +938,8 @@ struct file *hugetlb_file_setup(const char *name, size_t size, struct path path; struct dentry *root; struct qstr quick_string; + struct hstate *hstate; + int num_pages; *user = NULL; if (!hugetlbfs_vfsmount) @@ -967,10 +969,11 @@ struct file *hugetlb_file_setup(const char *name, size_t size, if (!inode) goto out_dentry; + hstate = hstate_inode(inode); + num_pages = ALIGN(size, huge_page_size(hstate)) >> + huge_page_shift(hstate); error = -ENOMEM; - if (hugetlb_reserve_pages(inode, 0, - size >> huge_page_shift(hstate_inode(inode)), NULL, - acctflag)) + if (hugetlb_reserve_pages(inode, 0, num_pages, NULL, acctflag)) goto out_inode; d_instantiate(path.dentry, inode); diff --git a/mm/mmap.c b/mm/mmap.c index 3f758c7..1f44ccf 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1098,8 +1098,12 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, * taken when vm_ops->mmap() is called * A dummy user value is used because we are not locking * memory so no accounting is necessary + * Length is increased by the amount necessary to align + * the base address to the huge page size. + * hugetlb_file_setup() aligns the end of the buffer to + * the huge page size. */ - len = ALIGN(len, huge_page_size(&default_hstate)); + len += ALIGN(addr, huge_page_size(&default_hstate)) - addr; file = hugetlb_file_setup(HUGETLB_ANON_FILE, len, VM_NORESERVE, &user, HUGETLB_ANONHUGE_INODE); if (IS_ERR(file)) -- 1.7.3.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>