vfs: atomic f_pos accesses as per POSIX

[~andy/linux] / fs / open.c

diff --git a/fs/open.c b/fs/open.c
index 4b3e1edf2fe4d917e69e56b3e268e32f2ae7301a..b9ed8b25c108c69d68889b5b6eadac9878eb7bd9 100644 (file)
--- a/fs/open.c
+++ b/fs/open.c
@@ -705,6 +705,10 @@ static int do_dentry_open(struct file *f,
                return 0;
        }
 
+       /* POSIX.1-2008/SUSv4 Section XSI 2.9.7 */
+       if (S_ISREG(inode->i_mode))
+               f->f_mode |= FMODE_ATOMIC_POS;
+
        f->f_op = fops_get(inode->i_fop);
        if (unlikely(WARN_ON(!f->f_op))) {
                error = -ENODEV;