glusterfs.git/xlators/storage/bd_map/src/bd_map.h, branch v3.4.2

build: declare lvm_lv_from_name() if it is missing from lvm2app.h

2013-06-27T12:39:43+00:00

The bd-xlator can not be built successfully on certain Debian
distributions due to a missing declaration of lvm_lv_from_name(). This
function is available for linking, but it does not exist in the header
file.

This change adds a detection for lvm_lv_from_name() in both the library
for linking, and the declaration in the header file. If the 1st is
missing, the bd-xlator can not be built, and if only the 2nd one is
missing, we'll declare lvm_lv_from_name() ourselves. This makes it
possible to build the bd-xlator on the affected Debian distributions
too.

Change-Id: If1845f6b6d676793677ebbcc6daf9ff12f7c3fd6
BUG: 976946
Signed-off-by: Niels de Vos 
Reviewed-on: http://review.gluster.org/5260
Reviewed-by: Vijay Bellur 
Tested-by: Gluster Build System

BD Backend: Create a new file (LV)

2012-11-29T17:36:56+00:00

Add support to create a new file (LV) under a directory (VG). By
default created LV is of one logical extent size.

Also setattr/fsetattr interfaces added as part of this patch.

BUG: 805138
Change-Id: I51752b707b3766ab277d623ce574537346f376c9
Signed-off-by: M. Mohan Kumar 
Reviewed-on: http://review.gluster.org/3554
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

BD Backend: Open,read and related calls support for LV

2012-11-29T17:35:43+00:00

BUG: 805138
Change-Id: I811c179d4244342537dbedb8a24fd2ec628942ed
Signed-off-by: M. Mohan Kumar 
Reviewed-on: http://review.gluster.org/3552
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

xlators: Add Block Device(BD) backend translator

2012-11-29T17:35:20+00:00

Add a new server storage xlator 'bd mapper'. Intention of this xlator is
to add block device backend support to gluster. It exports block devices
as regular files to the gluster client.

The immediate goal of this translator is to use logical volumes to
store VM images and expose them as files to QEMU/KVM.

Given Volume group is represented as directory and its logical
volumes as files.

By exporting LUNs/LVs as regular files, it becomes possible to:
* Associate each VM to a LV/LUN
* Use file system commands like cp to take copy of VM images
* Create linked clones of VM  by doing LV snapshot at server
side
* Implement thin provisioning by developing a qcow2 translator

As of now this patchset maps only logical volumes. BD Mapper volume
file specifies which Volume group to export to the client. BD xlator
exports the volume group as a directory and all logical volumes under that
as regular files.

BD xlator uses lvm2-devel APIs for getting the list of Volume Groups
and Logical Volumes in the system.

The eventual goal of this work is to support thin provisioning,
snapshot, copy etc of VM images seamlessly in glusterfs storage environment

BUG: 805138
Change-Id: I13b69d39d7fd199c101c8e9e4f2cf10772bdc3dd
Signed-off-by: M. Mohan Kumar 
Reviewed-on: http://review.gluster.org/3551
Reviewed-by: Vijay Bellur 
Tested-by: Vijay Bellur