Bug 1556972

Description of problem:
Users are experiencing empty directories at the client. If they know the name of the dirent they're attempting to use, they still can. For instance, if I know there's a directory, "foo", in the root of the mount, I can "cd foo" and it will work. The result of "ls foo" may also be empty despite there being files or directories there.

Touching a file or directory does not fix this.

There are no log entries on either the client or the brick.

Stopping and starting the volume has no effect.

To work around the issue, disable "performance.readdir-ahead" on the volume.

Version-Release number of selected component (if applicable):
Unclear. This has been happening since at least the 3.10 range and still occurs as late as 3.13.2.

How reproducible:
seemingly random

Steps to Reproduce:
unknown

Actual results:
$ ls -l /mnt/myvol
$ cat /mnt/myvol/foo
HERE!
$ mkdir /mnt/myvol/bar
$ ls -l /mnt/myvol
$

Expected results:
$ ls -l /mnt/myvol
-rw-r--r-- 1 jjulian jjulian  6 Mar 15 09:09 /mnt/myvol/foo
$ cat /mnt/myvol/foo
HERE!
$ ls -l /mnt/myvol
drwxr-xr-x 2 jjulian jjulian 40 Mar 15 09:10 /mnt/myvol/bar
-rw-r--r-- 1 jjulian jjulian  6 Mar 15 09:09 /mnt/myvol/foo
$