From ad8bc0d8901415eeea7bb27ef26f197918be0752 Mon Sep 17 00:00:00 2001
From: Max Reitz <mreitz@redhat.com>
Date: Sat, 13 Jun 2015 16:22:09 +0200
Subject: [PATCH 15/42] block: Add qemu_{,try_}blockalign0()

Message-id: <1434212556-3927-16-git-send-email-mreitz@redhat.com>
Patchwork-id: 66034
O-Subject: [RHEL-7.2 qemu-kvm PATCH 15/42] block: Add qemu_{,try_}blockalign0()
Bugzilla: 1129893
RH-Acked-by: Jeffrey Cody <jcody@redhat.com>
RH-Acked-by: Fam Zheng <famz@redhat.com>
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

BZ: 1129893

These functions call their non-0-counterparts and then fill the
allocated buffer with 0 (if the allocation has been successful).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit 9ebd84480583bb6d9a7666c079d99ff3266c423d)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 block.c               | 16 ++++++++++++++++
 include/block/block.h |  2 ++
 2 files changed, 18 insertions(+)

diff --git a/block.c b/block.c
index 1afa544..22ab762 100644
--- a/block.c
+++ b/block.c
@@ -5178,6 +5178,11 @@ void *qemu_blockalign(BlockDriverState *bs, size_t size)
     return qemu_memalign(bdrv_opt_mem_align(bs), size);
 }
 
+void *qemu_blockalign0(BlockDriverState *bs, size_t size)
+{
+    return memset(qemu_blockalign(bs, size), 0, size);
+}
+
 void *qemu_try_blockalign(BlockDriverState *bs, size_t size)
 {
     size_t align = bdrv_opt_mem_align(bs);
@@ -5191,6 +5196,17 @@ void *qemu_try_blockalign(BlockDriverState *bs, size_t size)
     return qemu_try_memalign(align, size);
 }
 
+void *qemu_try_blockalign0(BlockDriverState *bs, size_t size)
+{
+    void *mem = qemu_try_blockalign(bs, size);
+
+    if (mem) {
+        memset(mem, 0, size);
+    }
+
+    return mem;
+}
+
 /*
  * Check if all memory in this vector is sector aligned.
  */
diff --git a/include/block/block.h b/include/block/block.h
index 7b538b7..8339cac 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -417,7 +417,9 @@ void bdrv_img_create(const char *filename, const char *fmt,
 size_t bdrv_opt_mem_align(BlockDriverState *bs);
 void bdrv_set_guest_block_size(BlockDriverState *bs, int align);
 void *qemu_blockalign(BlockDriverState *bs, size_t size);
+void *qemu_blockalign0(BlockDriverState *bs, size_t size);
 void *qemu_try_blockalign(BlockDriverState *bs, size_t size);
+void *qemu_try_blockalign0(BlockDriverState *bs, size_t size);
 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
 
 struct HBitmapIter;
-- 
1.8.3.1