[PATCH 2/4] hw/arm: use g_autofree for fdt in arm_load_dtb

["Alex Bennée" <alex.bennee@linaro.org>]

With the fdt being protected by g_autofree we can skip the goto fail
and bail out straight away. The only thing we must take care of is
stealing the pointer in the one case when we do need it to survive.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
---
 hw/arm/boot.c | 29 ++++++++++++-----------------
 1 file changed, 12 insertions(+), 17 deletions(-)

diff --git a/hw/arm/boot.c b/hw/arm/boot.c
index 56fd13b9f7c..749f2d08341 100644
--- a/hw/arm/boot.c
+++ b/hw/arm/boot.c
@@ -519,7 +519,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
                  hwaddr addr_limit, AddressSpace *as, MachineState *ms,
                  ARMCPU *cpu)
 {
-    void *fdt = NULL;
+    g_autofree void *fdt = NULL;
     int size, rc, n = 0;
     uint32_t acells, scells;
     unsigned int i;
@@ -538,13 +538,13 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
         fdt = load_device_tree(filename, &size);
         if (!fdt) {
             fprintf(stderr, "Couldn't open dtb file %s\n", filename);
-            goto fail;
+            return -1;
         }
     } else {
         fdt = binfo->get_dtb(binfo, &size);
         if (!fdt) {
             fprintf(stderr, "Board was unable to create a dtb blob\n");
-            goto fail;
+            return -1;
         }
     }
 
@@ -553,7 +553,6 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
          * Whether this constitutes failure is up to the caller to decide,
          * so just return 0 as size, i.e., no error.
          */
-        g_free(fdt);
         return 0;
     }
 
@@ -563,7 +562,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
                                    NULL, &error_fatal);
     if (acells == 0 || scells == 0) {
         fprintf(stderr, "dtb file invalid (#address-cells or #size-cells 0)\n");
-        goto fail;
+        return -1;
     }
 
     if (scells < 2 && binfo->ram_size >= 4 * GiB) {
@@ -572,14 +571,14 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
          */
         fprintf(stderr, "qemu: dtb file not compatible with "
                 "RAM size > 4GB\n");
-        goto fail;
+        return -1;
     }
 
     /* nop all root nodes matching /memory or /memory@unit-address */
     node_path = qemu_fdt_node_unit_path(fdt, "memory", &err);
     if (err) {
         error_report_err(err);
-        goto fail;
+        return -1;
     }
     while (node_path[n]) {
         if (g_str_has_prefix(node_path[n], "/memory")) {
@@ -611,7 +610,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
             if (rc < 0) {
                 fprintf(stderr, "couldn't add /memory@%"PRIx64" node\n",
                         mem_base);
-                goto fail;
+                return -1;
             }
 
             mem_base += mem_len;
@@ -622,7 +621,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
         if (rc < 0) {
             fprintf(stderr, "couldn't add /memory@%"PRIx64" node\n",
                     binfo->loader_start);
-            goto fail;
+            return -1;
         }
     }
 
@@ -636,7 +635,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
                                      ms->kernel_cmdline);
         if (rc < 0) {
             fprintf(stderr, "couldn't set /chosen/bootargs\n");
-            goto fail;
+            return -1;
         }
     }
 
@@ -645,7 +644,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
                                           acells, binfo->initrd_start);
         if (rc < 0) {
             fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");
-            goto fail;
+            return -1;
         }
 
         rc = qemu_fdt_setprop_sized_cells(fdt, "/chosen", "linux,initrd-end",
@@ -654,7 +653,7 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
                                           binfo->initrd_size);
         if (rc < 0) {
             fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");
-            goto fail;
+            return -1;
         }
     }
 
@@ -673,14 +672,10 @@ int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
 
     if (fdt != ms->fdt) {
         g_free(ms->fdt);
-        ms->fdt = fdt;
+        ms->fdt = g_steal_pointer(&fdt);
     }
 
     return size;
-
-fail:
-    g_free(fdt);
-    return -1;
 }
 
 static void do_cpu_reset(void *opaque)
-- 
2.47.2