libqos: add malloc support

This is a very simple allocator for the PC platform.  It should
be possible to add backends for other platforms.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Message-id: 1366123521-4330-5-git-send-email-aliguori@us.ibm.com

tests/libqos/malloc-pc.c

@@ -0,0 +1,71 @@
+/*
+ * libqos malloc support for PC
+ *
+ * Copyright IBM, Corp. 2012-2013
+ *
+ * Authors:
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "libqos/malloc-pc.h"
+#include "libqos/fw_cfg-pc.h"
+
+#define NO_QEMU_PROTOS
+#include "hw/nvram/fw_cfg.h"
+
+#include "qemu-common.h"
+#include <glib.h>
+
+#define PAGE_SIZE (4096)
+
+typedef struct PCAlloc
+{
+    QGuestAllocator alloc;
+
+    uint64_t start;
+    uint64_t end;
+} PCAlloc;
+
+static uint64_t pc_alloc(QGuestAllocator *allocator, size_t size)
+{
+    PCAlloc *s = container_of(allocator, PCAlloc, alloc);
+    uint64_t addr;
+
+
+    size += (PAGE_SIZE - 1);
+    size &= PAGE_SIZE;
+
+    g_assert_cmpint((s->start + size), <=, s->end);
+
+    addr = s->start;
+    s->start += size;
+
+    return addr;
+}
+
+static void pc_free(QGuestAllocator *allocator, uint64_t addr)
+{
+}
+
+QGuestAllocator *pc_alloc_init(void)
+{
+    PCAlloc *s = g_malloc0(sizeof(*s));
+    uint64_t ram_size;
+    QFWCFG *fw_cfg = pc_fw_cfg_init();
+
+    s->alloc.alloc = pc_alloc;
+    s->alloc.free = pc_free;
+
+    ram_size = qfw_cfg_get_u64(fw_cfg, FW_CFG_RAM_SIZE);
+
+    /* Start at 1MB */
+    s->start = 1 << 20;
+
+    /* Respect PCI hole */
+    s->end = MIN(ram_size, 0xE0000000);
+
+    return &s->alloc;
+}