Blob Blame Raw
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