gluster: add fallocate fop support

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 <bfoster@redhat.com>
Reviewed-on: http://review.gluster.org/4969
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/xlators/performance/open-behind/src/open-behind.c b/xlators/performance/open-behind/src/open-behind.c
index b405b94cd54..5ac813132eb 100644
--- a/xlators/performance/open-behind/src/open-behind.c
+++ b/xlators/performance/open-behind/src/open-behind.c
@@ -681,6 +681,24 @@ err:
 	return 0;
 }
 
+int
+ob_fallocate(call_frame_t *frame, xlator_t *this, fd_t *fd, int32_t mode,
+	     off_t offset, size_t len, dict_t *xdata)
+{
+	call_stub_t *stub;
+
+	stub = fop_fallocate_stub(frame, default_fallocate_resume, fd, mode,
+				  offset, len, xdata);
+	if (!stub)
+		goto err;
+
+	open_and_resume(this, fd, stub);
+
+	return 0;
+err:
+	STACK_UNWIND_STRICT(fallocate, frame, -1, ENOMEM, NULL, NULL, NULL);
+	return 0;
+}
 
 int
 ob_unlink (call_frame_t *frame, xlator_t *this, loc_t *loc, int xflags,
@@ -903,6 +921,7 @@ struct xlator_fops fops = {
 	.fentrylk    = ob_fentrylk,
 	.fxattrop    = ob_fxattrop,
 	.fsetattr    = ob_fsetattr,
+	.fallocate   = ob_fallocate,
 	.unlink      = ob_unlink,
 	.rename      = ob_rename,
 	.lk          = ob_lk,