glusterfs.git/api/src/glfs.h, branch v3.5.0beta5

zerofill: Change the type of len argument of glfs_zerofill() to off_t

2013-11-15T07:29:48+00:00

glfs_zerofill() can be potentially called to zero-out entire file and
hence allow for bigger value of length parameter.

Change-Id: I75f1d11af298915049a3f3a7cb3890a2d72fca63
BUG: 1028673
Signed-off-by: Bharata B Rao 
Reviewed-on: http://review.gluster.org/6266
Tested-by: Gluster Build System 
Reviewed-by: M. Mohan Kumar 
Tested-by: M. Mohan Kumar 
Reviewed-by: Anand Avati

gfapi: introduce glfs_readdir() and glfs_readdirplus() APIs

2013-11-13T18:48:18+00:00

Change-Id: I6b233bf647585675f233898351bf593f251716cc
BUG: 839950
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/6201
Tested-by: Gluster Build System 
Reviewed-by: Raghavendra Talur

glusterfs: zerofill support

2013-11-11T05:25:49+00:00

Add support for a new ZEROFILL fop. Zerofill writes zeroes to a file in
the specified range. This fop will be useful when a whole file needs to
be initialized with zero (could be useful for zero filled VM disk image
provisioning or  during scrubbing of VM disk images).

Client/application can issue this FOP for zeroing out. Gluster server
will zero out required range of bytes ie server offloaded zeroing. In
the absence of this fop,  client/application has to repetitively issue
write (zero) fop to the server, which is very inefficient method because
of the overheads involved in RPC calls  and acknowledgements.

WRITESAME is a  SCSI T10 command that takes a block of data as input and
writes the same data to other blocks and this write is handled
completely within the storage and hence is known as offload . Linux ,now
has support for SCSI WRITESAME command which is exposed to the user in
the form of BLKZEROOUT ioctl.  BD Xlator can exploit BLKZEROOUT ioctl to
implement this fop. Thus zeroing out operations can be completely
offloaded to the storage device , making it highly efficient.

The fop takes two arguments offset and size. It zeroes out 'size' number
of bytes in an opened file starting from 'offset' position.

This patch adds zerofill support to the following areas:
	- libglusterfs
	- io-stats
	- performance/md-cache,open-behind
	- quota
	- cluster/afr,dht,stripe
	- rpc/xdr
	- protocol/client,server
	- io-threads
	- marker
	- storage/posix
	- libgfapi

Client applications can exloit this fop by using glfs_zerofill introduced in
libgfapi.FUSE support to this fop has not been added as there is no system call
for this fop.

Changes from previous version 3:
* Removed redundant memory failure log messages

Changes from previous version 2:
* Rebased and fixed build error

Changes from previous version 1:
* Rebased for latest master

TODO :
     * Add zerofill support to trace xlator
     * Expose zerofill capability as part of gluster volume info

Here is a performance comparison of server offloaded zeofill vs zeroing
out using repeated writes.

[root@llmvm02 remote]# time ./offloaded aakash-test log 20

real	3m34.155s
user	0m0.018s
sys	0m0.040s
[root@llmvm02 remote]# time ./manually aakash-test log 20

real	4m23.043s
user	0m2.197s
sys	0m14.457s
[root@llmvm02 remote]# time ./offloaded aakash-test log 25;

real	4m28.363s
user	0m0.021s
sys	0m0.025s
[root@llmvm02 remote]# time ./manually aakash-test log 25

real	5m34.278s
user	0m2.957s
sys	0m18.808s

The argument log is a file which we want to set for logging purpose and
the third argument is size in GB .

As we can see there is a performance improvement of around 20% with this
fop.

Change-Id: I081159f5f7edde0ddb78169fb4c21c776ec91a18
BUG: 1028673
Signed-off-by: Aakash Lal Das 
Signed-off-by: M. Mohan Kumar 
Reviewed-on: http://review.gluster.org/5327
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

gfapi: object handle based API extensions

2013-10-11T19:16:46+00:00

There is an ongoing effort to integrate NFS Ganesha (
https://github.com/nfs-ganesha/nfs-ganesha/wiki ) with GlusterFS as one of
the file system back ends.

Towards this we need extensions to gfapi that can handle object based
operations. Meaning, instead of using full paths or relative paths from
cwd, it is required that we can work with APIs, like the *at POSIX
variants, to be able to create, lookup, open etc. files and directories.
Hence the objects are the files or directories themselves and we give out
handles to these objects that can be used for further operations.

This code drop is an initial implementation of the proposed APIs.

The new APIs are implemented as glfs_h_XXX variants in the file
glfs-handleops.c to mirror glfs-fops.c style. The code leverages holding
onto inode references and doling these out as opaque/cookie type objects to
the callers, to enable them to be used as handles in other operations.

An fd based approach was considered, but due to the extra footprint that
the fd structure and its counterparts would incur, this was dropped to take
the approach of holding inode references themselves.

Tested by extending glfsxmp.c to invoke and exercise the added APIs, and
further tested with a reference integration of the same as an FSAL with NFS
Ganesha.

Change-Id: I23629c99e905b54070fa2e6565147812e5f3fa5d
BUG: 1016000
Signed-off-by: R.Shyamsundar 
Reviewed-on: http://review.gluster.org/5936
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

logging: Expose set_log_file_path() in libglusterfs.

2013-09-24T19:00:54+00:00

This patch also changes the behavior of glfs_set_logging().
If logfile argument is not provided to glfs_set_logging(),
libgfapi uses set_log_file_path() to create a logfile.

Change-Id: I49ec66c7f16f5604ff2f7cf7b365b08a05b5460d
BUG: 764890
Signed-off-by: Vijay Bellur 
Reviewed-on: http://review.gluster.org/5910
Reviewed-by: Anand Avati 
Tested-by: Anand Avati

gfapi: implement a minimial glfs_fini()

2013-09-17T18:42:12+00:00

At the very least, we should PARENT_DOWN on the currently active
graph and disconnect ourselves from glusterd.

Further cleanups underway.

Change-Id: I9276686a84b0975b5ce272b4cbec1b80920d5c5c
BUG: 1004519
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/5788
Tested-by: Gluster Build System 
Reviewed-by: Raghavendra Bhat 
Reviewed-by: Amar Tumballi

gfapi: Add description of glfs_io_cbk function as a comment

2013-08-23T10:37:23+00:00

No code change, just add a comment describing the callback function
type.

Change-Id: I3a5c5b3d3fe042b4f535963dd477806832c15704
BUG: 839950
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/5696
Reviewed-by: Vijay Bellur 
Tested-by: Vijay Bellur

gfapi: async discard support

2013-06-13T21:38:57+00:00

From: Bharata B Rao 

Add glfs_discard_async() to meet QEMU's discard requirements.

BUG: 963678
Change-Id: I97723107fca88dd96cddc08cd67a286645a37922
Signed-off-by: Bharata B Rao 
Signed-off-by: Brian Foster 
Reviewed-on: http://review.gluster.org/5144
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

glusterfs: discard (hole punch) support

2013-06-13T21:37:43+00:00

Add support for the DISCARD file operation. Discard punches a hole
in a file in the provided range. Block de-allocation is implemented
via fallocate() (as requested via fuse and passed on to the brick
fs) but a separate fop is created within gluster to emphasize the
fact that discard changes file data (the discarded region is
replaced with zeroes) and must invalidate caches where appropriate.

BUG: 963678
Change-Id: I34633a0bfff2187afeab4292a15f3cc9adf261af
Signed-off-by: Brian Foster 
Reviewed-on: http://review.gluster.org/5090
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

gluster: add fallocate fop support

2013-06-13T21:37:21+00:00

Implement support for the fallocate file operation. fallocate
allocates blocks for a particular inode such that future writes
to the associated region of the file are guaranteed not to fail
with ENOSPC.

This patch adds fallocate support to the following areas:

	- libglusterfs
	- mount/fuse
	- io-stats
	- performance/md-cache,open-behind
	- quota
	- cluster/afr,dht,stripe
	- rpc/xdr
	- protocol/client,server
	- io-threads
	- marker
	- storage/posix
	- libgfapi

BUG: 949242
Change-Id: Ice8e61351f9d6115c5df68768bc844abbf0ce8bd
Signed-off-by: Brian Foster 
Reviewed-on: http://review.gluster.org/4969
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati