posix: Set correct d_type for readdirp() calls

dirent.d_type can contain the type of the directory entry. The 'd_type'
struct member in dirent is present in Linux and many BSD flavours.
However, filling d_type with correct value requires support from the
underlying filesystem. If not, d_type is set to DT_UNKNOWN. XFS added
support for d_type as part of their newer version 5 on-disk format.
However, this requires Linux >= 3.15, xfsprogs >= 3.2.0 and the bricks
to be formatted using the new format.

This patch enables posix xlator to set d_type to the right value even
when the underlying filesystem does not support it. d_type can be set
using information previously fetched by stat() on the dir entry.
This will aid FUSE applications to leverage d_type to avoid the expense
of calling lstat() if further actions depend on the type of the file.

Refer `man 3 readdir` and `man 2 getdents`

> Change-Id: Ic5a262fe4c64122726b4fae2d1bea375c559ca04
> Signed-off-by: Prashanth Pai <ppai@redhat.com>
> Reviewed-on: http://review.gluster.org/14095
> Smoke: Gluster Build System <jenkins@build.gluster.com>
> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
> CentOS-regression: Gluster Build System <jenkins@build.gluster.com>
> Reviewed-by: Jeff Darcy <jdarcy@redhat.com>

(cherry picked from commit 77def44d497d090ef3f393b6d9403c1a29dcf993)

Change-Id: I8de1e643dbe88c57eb7a946357283f46c30ae701
BUG: 1332397
Signed-off-by: Prashanth Pai <ppai@redhat.com>
Reviewed-on: http://review.gluster.org/14176
Smoke: Gluster Build System <jenkins@build.gluster.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>

0 files changed, 0 insertions, 0 deletions