diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 300844f50dcd..cb62c8f07d1e 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -784,9 +784,13 @@ static inline bool should_fault_in_pages(struct iov_iter *i, if (!user_backed_iter(i)) return false; + /* + * Try to fault in multiple pages initially. When that doesn't result + * in any progress, fall back to a single page. + */ size = PAGE_SIZE; offs = offset_in_page(iocb->ki_pos); - if (*prev_count != count || !*window_size) { + if (*prev_count != count) { size_t nr_dirtied; nr_dirtied = max(current->nr_dirtied_pause - @@ -870,6 +874,7 @@ static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from, struct gfs2_inode *ip = GFS2_I(inode); size_t prev_count = 0, window_size = 0; size_t written = 0; + bool enough_retries; ssize_t ret; /* @@ -913,11 +918,17 @@ static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from, if (ret > 0) written = ret; + enough_retries = prev_count == iov_iter_count(from) && + window_size <= PAGE_SIZE; if (should_fault_in_pages(from, iocb, &prev_count, &window_size)) { gfs2_glock_dq(gh); window_size -= fault_in_iov_iter_readable(from, window_size); - if (window_size) - goto retry; + if (window_size) { + if (!enough_retries) + goto retry; + /* fall back to buffered I/O */ + ret = 0; + } } out_unlock: if (gfs2_holder_queued(gh))