From 09679a280cd7aea04c13ae58bdb28021d9674782 Mon Sep 17 00:00:00 2001
From: Boaz Harrosh <bharrosh@panasas.com>
Date: Tue, 13 Mar 2012 20:44:26 -0700
Subject: [PATCH] --- yaml --- r: 294559 b: refs/heads/master c:
 5318a29c1943e9719e71495db6efb6fc084a45a9 h: refs/heads/master i:   294557:
 033a1d775dae24d109ac792b93c387944cb50bf2   294555:
 aca741877d00d9b55cbd23d673afa2dedebb1ae9   294551:
 f5cc9e2fb10c91de3e3a4caa38c21338b9978075   294543:
 e9aabb545faa218b8555422c7a296e393db22f24   294527:
 b468bf97d9f900a23098d0b24a717daf1c4f9fbf v: v3

---
 [refs]                             |  2 +-
 trunk/fs/nfs/objlayout/objio_osd.c | 39 +++++++++++++++++++-----------
 2 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/[refs] b/[refs]
index 5731edc66460..577e6548f517 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e138ead73f872559778bb0c326e795206f96d3ce
+refs/heads/master: 5318a29c1943e9719e71495db6efb6fc084a45a9
diff --git a/trunk/fs/nfs/objlayout/objio_osd.c b/trunk/fs/nfs/objlayout/objio_osd.c
index 405a62bdb9b4..3a621a2fd321 100644
--- a/trunk/fs/nfs/objlayout/objio_osd.c
+++ b/trunk/fs/nfs/objlayout/objio_osd.c
@@ -205,25 +205,36 @@ static void copy_single_comp(struct ore_components *oc, unsigned c,
 int __alloc_objio_seg(unsigned numdevs, gfp_t gfp_flags,
 		       struct objio_segment **pseg)
 {
-	struct __alloc_objio_segment {
-		struct objio_segment olseg;
-		struct ore_dev *ods[numdevs];
-		struct ore_comp	comps[numdevs];
-	} *aolseg;
-
-	aolseg = kzalloc(sizeof(*aolseg), gfp_flags);
-	if (unlikely(!aolseg)) {
+/*	This is the in memory structure of the objio_segment
+ *
+ *	struct __alloc_objio_segment {
+ *		struct objio_segment olseg;
+ *		struct ore_dev *ods[numdevs];
+ *		struct ore_comp	comps[numdevs];
+ *	} *aolseg;
+ *	NOTE: The code as above compiles and runs perfectly. It is elegant,
+ *	type safe and compact. At some Past time Linus has decided he does not
+ *	like variable length arrays, For the sake of this principal we uglify
+ *	the code as below.
+ */
+	struct objio_segment *lseg;
+	size_t lseg_size = sizeof(*lseg) +
+			numdevs * sizeof(lseg->oc.ods[0]) +
+			numdevs * sizeof(*lseg->oc.comps);
+
+	lseg = kzalloc(lseg_size, gfp_flags);
+	if (unlikely(!lseg)) {
 		dprintk("%s: Faild allocation numdevs=%d size=%zd\n", __func__,
-			numdevs, sizeof(*aolseg));
+			numdevs, lseg_size);
 		return -ENOMEM;
 	}
 
-	aolseg->olseg.oc.numdevs = numdevs;
-	aolseg->olseg.oc.single_comp = EC_MULTPLE_COMPS;
-	aolseg->olseg.oc.comps = aolseg->comps;
-	aolseg->olseg.oc.ods = aolseg->ods;
+	lseg->oc.numdevs = numdevs;
+	lseg->oc.single_comp = EC_MULTPLE_COMPS;
+	lseg->oc.ods = (void *)(lseg + 1);
+	lseg->oc.comps = (void *)(lseg->oc.ods + numdevs);
 
-	*pseg = &aolseg->olseg;
+	*pseg = lseg;
 	return 0;
 }