Commit b7f55d92 authored by Andreas Gruenbacher's avatar Andreas Gruenbacher
Browse files

gfs2: Fix mmap locking for write faults 



When a write fault occurs, we need to take the inode glock of the underlying
inode in exclusive mode.  Otherwise, there's no guarantee that the dirty page
will be written back to disk.

Signed-off-by: default avatarAndreas Gruenbacher <agruenba@redhat.com>
parent f5456b5d

fs/gfs2/file.c

+3 −1
Original line number Diff line number Diff line
@@ -540,9 +540,11 @@ static vm_fault_t gfs2_fault(struct vm_fault *vmf) 
	struct gfs2_inode *ip = GFS2_I(inode);

	struct gfs2_holder gh;

	vm_fault_t ret;

	u16 state;

	int err;



	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);

	state = (vmf->flags & FAULT_FLAG_WRITE) ? LM_ST_EXCLUSIVE : LM_ST_SHARED;

	gfs2_holder_init(ip->i_gl, state, 0, &gh);

	err = gfs2_glock_nq(&gh);

	if (err) {

		ret = block_page_mkwrite_return(err);