From 90fad0c40a1947e229fdf82a30219e33a3e1dad8 Mon Sep 17 00:00:00 2001

From: Max Reitz <mreitz@redhat.com>

Date: Sat, 13 Jun 2015 16:21:57 +0200

Subject: [PATCH 03/42] block: Introduce qemu_try_blockalign()

Message-id: <1434212556-3927-4-git-send-email-mreitz@redhat.com>

Patchwork-id: 66022

O-Subject: [RHEL-7.2 qemu-kvm PATCH 03/42] block: Introduce qemu_try_blockalign()

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>

From: Kevin Wolf <kwolf@redhat.com>

BZ: 1129893

This function returns NULL instead of aborting when an allocation fails.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Reviewed-by: Benoit Canet <benoit@irqsave.net>

(cherry picked from commit 7d2a35cc921ea4832083a7e8598461868bb538ce)

Signed-off-by: Max Reitz <mreitz@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 block.c               | 13 +++++++++++++

 include/block/block.h |  1 +

 include/qemu/osdep.h  |  1 +

 util/oslib-posix.c    | 16 ++++++++++------

 util/oslib-win32.c    |  9 +++++++--

 5 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/block.c b/block.c

index f2caf20..caea2ea 100644

--- a/block.c

+++ b/block.c

@@ -5175,6 +5175,19 @@ void *qemu_blockalign(BlockDriverState *bs, size_t size)

     return qemu_memalign(bdrv_opt_mem_align(bs), size);

 }

+void *qemu_try_blockalign(BlockDriverState *bs, size_t size)

+{

+    size_t align = bdrv_opt_mem_align(bs);

+

+    /* Ensure that NULL is never returned on success */

+    assert(align > 0);

+    if (size == 0) {

+        size = align;

+    }

+

+    return qemu_try_memalign(align, size);

+}

+

 /*

  * Check if all memory in this vector is sector aligned.

  */

diff --git a/include/block/block.h b/include/block/block.h

index 3170cbc..7b538b7 100644

--- a/include/block/block.h

+++ b/include/block/block.h

@@ -417,6 +417,7 @@ 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_try_blockalign(BlockDriverState *bs, size_t size);

 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);

 struct HBitmapIter;

diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h

index 7a5ae28..8984da0 100644

--- a/include/qemu/osdep.h

+++ b/include/qemu/osdep.h

@@ -95,6 +95,7 @@ typedef signed int              int_fast16_t;

 #define qemu_printf printf

 int qemu_daemon(int nochdir, int noclose);

+void *qemu_try_memalign(size_t alignment, size_t size);

 void *qemu_memalign(size_t alignment, size_t size);

 void *qemu_anon_ram_alloc(size_t size);

 void qemu_vfree(void *ptr);

diff --git a/util/oslib-posix.c b/util/oslib-posix.c

index fef840a..f0fb297 100644

--- a/util/oslib-posix.c

+++ b/util/oslib-posix.c

@@ -83,7 +83,7 @@ void *qemu_oom_check(void *ptr)

     return ptr;

 }

-void *qemu_memalign(size_t alignment, size_t size)

+void *qemu_try_memalign(size_t alignment, size_t size)

 {

     void *ptr;

@@ -95,19 +95,23 @@ void *qemu_memalign(size_t alignment, size_t size)

     int ret;

     ret = posix_memalign(&ptr, alignment, size);

     if (ret != 0) {

-        fprintf(stderr, "Failed to allocate %zu B: %s\n",

-                size, strerror(ret));

-        abort();

+        errno = ret;

+        ptr = NULL;

     }

 #elif defined(CONFIG_BSD)

-    ptr = qemu_oom_check(valloc(size));

+    ptr = valloc(size);

 #else

-    ptr = qemu_oom_check(memalign(alignment, size));

+    ptr = memalign(alignment, size);

 #endif

     trace_qemu_memalign(alignment, size, ptr);

     return ptr;

 }

+void *qemu_memalign(size_t alignment, size_t size)

+{

+    return qemu_oom_check(qemu_try_memalign(alignment, size));

+}

+

 /* alloc shared memory pages */

 void *qemu_anon_ram_alloc(size_t size)

 {

diff --git a/util/oslib-win32.c b/util/oslib-win32.c

index 332e743..0fb78ef 100644

--- a/util/oslib-win32.c

+++ b/util/oslib-win32.c

@@ -46,18 +46,23 @@ void *qemu_oom_check(void *ptr)

     return ptr;

 }

-void *qemu_memalign(size_t alignment, size_t size)

+void *qemu_try_memalign(size_t alignment, size_t size)

 {

     void *ptr;

     if (!size) {

         abort();

     }

-    ptr = qemu_oom_check(VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE));

+    ptr = VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);

     trace_qemu_memalign(alignment, size, ptr);

     return ptr;

 }

+void *qemu_memalign(size_t alignment, size_t size)

+{

+    return qemu_oom_check(qemu_try_memalign(alignment, size));

+}

+

 void *qemu_anon_ram_alloc(size_t size)

 {

     void *ptr;

-- 

1.8.3.1