From 91aea6ec78170ffeb64a2a374ba69bce4986b86f Mon Sep 17 00:00:00 2001
From: Jens Axboe <jaxboe@fusionio.com>
Date: Mon, 25 Apr 2011 20:46:58 +0200
Subject: [PATCH 1/1] Add simple aligned alloc helper

We don't have posix_memalign() on some Solaris and Darwin, so just
add a poor mans implementation of it. Outside of arch code where
we have proper posix_memalign(), this is only used to ensure good
alignment of the io_u in the core code.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
---
 Makefile   |  3 ++-
 fio.c      |  8 +++++---
 memalign.c | 35 +++++++++++++++++++++++++++++++++++
 memalign.h |  7 +++++++
 4 files changed, 49 insertions(+), 4 deletions(-)
 create mode 100644 memalign.c
 create mode 100644 memalign.h

diff --git a/Makefile b/Makefile
index 1d815624..0dc997c8 100644
--- a/Makefile
+++ b/Makefile
@@ -13,7 +13,8 @@ SOURCE = gettime.c fio.c ioengines.c init.c stat.c log.c time.c filesetup.c \
 		eta.c verify.c memory.c io_u.c parse.c mutex.c options.c \
 		rbtree.c smalloc.c filehash.c profile.c debug.c lib/rand.c \
 		lib/num2str.c $(wildcard crc/*.c) engines/cpu.c \
-		engines/mmap.c engines/sync.c engines/null.c engines/net.c
+		engines/mmap.c engines/sync.c engines/null.c engines/net.c \
+		memalign.c
 
 ifeq ($(UNAME), Linux)
   SOURCE += diskutil.c fifo.c blktrace.c helpers.c cgroup.c trim.c \
diff --git a/fio.c b/fio.c
index e205b3aa..a737a310 100644
--- a/fio.c
+++ b/fio.c
@@ -45,6 +45,7 @@
 #include "cgroup.h"
 #include "profile.h"
 #include "lib/rand.h"
+#include "memalign.h"
 
 unsigned long page_mask;
 unsigned long page_size;
@@ -796,7 +797,7 @@ static void cleanup_io_u(struct thread_data *td)
 		io_u = flist_entry(entry, struct io_u, list);
 
 		flist_del(&io_u->list);
-		free(io_u);
+		fio_memfree(io_u, sizeof(*io_u));
 	}
 
 	free_io_mem(td);
@@ -843,8 +844,9 @@ static int init_io_u(struct thread_data *td)
 		if (td->terminate)
 			return 1;
 
-		if (posix_memalign(&ptr, cl_align, sizeof(*io_u))) {
-			log_err("fio: posix_memalign=%s\n", strerror(errno));
+		ptr = fio_memalign(cl_align, sizeof(*io_u));
+		if (!ptr) {
+			log_err("fio: unable to allocate aligned memory\n");
 			break;
 		}
 
diff --git a/memalign.c b/memalign.c
new file mode 100644
index 00000000..87667b42
--- /dev/null
+++ b/memalign.c
@@ -0,0 +1,35 @@
+#include <stdlib.h>
+#include <assert.h>
+
+#include "memalign.h"
+
+struct align_footer {
+	unsigned int offset;
+};
+
+#define PTR_ALIGN(ptr, mask)	\
+	(char *) (((unsigned long) ((ptr) + (mask)) & ~(mask)))
+
+void *fio_memalign(size_t alignment, size_t size)
+{
+	struct align_footer *f;
+	void *ptr, *ret = NULL;
+
+	assert(!(alignment & (alignment - 1)));
+
+	ptr = malloc(size + alignment + size + sizeof(*f) - 1);
+	if (ptr) {
+		ret = PTR_ALIGN(ptr, alignment);
+		f = ret + size;
+		f->offset = (unsigned long) ret - (unsigned long) ptr;
+	}
+
+	return ret;
+}
+
+void fio_memfree(void *ptr, size_t size)
+{
+	struct align_footer *f = ptr + size;
+
+	free(ptr - f->offset);
+}
diff --git a/memalign.h b/memalign.h
new file mode 100644
index 00000000..df412e28
--- /dev/null
+++ b/memalign.h
@@ -0,0 +1,7 @@
+#ifndef FIO_MEMALIGN_H
+#define FIO_MEMALIGN_H
+
+extern void *fio_memalign(size_t alignment, size_t size);
+extern void fio_memfree(void *ptr, size_t size);
+
+#endif
-- 
2.25.1