mm: make do_mmap_pgoff return populate as a size in bytes, not as a bool

do_mmap_pgoff() rounds up the desired size to the next PAGE_SIZE
multiple, however there was no equivalent code in mm_populate(), which
caused issues.

This could be fixed by introduced the same rounding in mm_populate(),
however I think it's preferable to make do_mmap_pgoff() return populate
as a size rather than as a boolean, so we don't have to duplicate the
size rounding logic in mm_populate().

Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Andy Lutomirski <luto@amacapital.net>
Cc: Greg Ungerer <gregungerer@westnet.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/ipc/shm.c b/ipc/shm.c
index 9f047ba..be3ec9a 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -971,7 +971,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr,
 	struct shm_file_data *sfd;
 	struct path path;
 	fmode_t f_mode;
-	bool populate = false;
+	unsigned long populate = 0;
 
 	err = -EINVAL;
 	if (shmid < 0)
@@ -1078,7 +1078,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr,
 invalid:
 	up_write(&current->mm->mmap_sem);
 	if (populate)
-		mm_populate(addr, size);
+		mm_populate(addr, populate);
 
 out_fput:
 	fput(file);