exec: add parameter errp to qemu_ram_alloc and qemu_ram_alloc_from_ptr

Add parameter errp to qemu_ram_alloc and qemu_ram_alloc_from_ptr so that
we can handle errors.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
[Assert ptr != NULL in memory_region_init_ram_ptr. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

exec.c

@@ -1259,7 +1259,7 @@ static int memory_try_enable_merging(void *addr, size_t len)
     return qemu_madvise(addr, len, QEMU_MADV_MERGEABLE);
 }
 
-static ram_addr_t ram_block_add(RAMBlock *new_block)
+static ram_addr_t ram_block_add(RAMBlock *new_block, Error **errp)
 {
     RAMBlock *block;
     ram_addr_t old_ram_size, new_ram_size;
@@ -1276,9 +1276,11 @@ static ram_addr_t ram_block_add(RAMBlock *new_block)
         } else {
             new_block->host = phys_mem_alloc(new_block->length);
             if (!new_block->host) {
-                fprintf(stderr, "Cannot set up guest memory '%s': %s\n",
+                error_setg_errno(errp, errno,
-                        memory_region_name(new_block->mr), strerror(errno));
+                                 "cannot set up guest memory '%s'",
-                exit(1);
+                                 memory_region_name(new_block->mr));
+                qemu_mutex_unlock_ramlist();
+                return -1;
             }
             memory_try_enable_merging(new_block->host, new_block->length);
         }
@@ -1329,6 +1331,8 @@ ram_addr_t qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
                                     Error **errp)
 {
     RAMBlock *new_block;
+    ram_addr_t addr;
+    Error *local_err = NULL;
 
     if (xen_enabled()) {
         error_setg(errp, "-mem-path not supported with Xen");
@@ -1358,14 +1362,22 @@ ram_addr_t qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
         return -1;
     }
 
-    return ram_block_add(new_block);
+    addr = ram_block_add(new_block, &local_err);
+    if (local_err) {
+        g_free(new_block);
+        error_propagate(errp, local_err);
+        return -1;
+    }
+    return addr;
 }
 #endif
 
 ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
-                                   MemoryRegion *mr)
+                                   MemoryRegion *mr, Error **errp)
 {
     RAMBlock *new_block;
+    ram_addr_t addr;
+    Error *local_err = NULL;
 
     size = TARGET_PAGE_ALIGN(size);
     new_block = g_malloc0(sizeof(*new_block));
@@ -1376,12 +1388,18 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
     if (host) {
         new_block->flags |= RAM_PREALLOC;
     }
-    return ram_block_add(new_block);
+    addr = ram_block_add(new_block, &local_err);
+    if (local_err) {
+        g_free(new_block);
+        error_propagate(errp, local_err);
+        return -1;
+    }
+    return addr;
 }
 
-ram_addr_t qemu_ram_alloc(ram_addr_t size, MemoryRegion *mr)
+ram_addr_t qemu_ram_alloc(ram_addr_t size, MemoryRegion *mr, Error **errp)
 {
-    return qemu_ram_alloc_from_ptr(size, NULL, mr);
+    return qemu_ram_alloc_from_ptr(size, NULL, mr, errp);
 }
 
 void qemu_ram_free_from_ptr(ram_addr_t addr)

include/exec/ram_addr.h

@@ -26,8 +26,8 @@ ram_addr_t qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
                                     bool share, const char *mem_path,
                                     Error **errp);
 ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
-                                   MemoryRegion *mr);
+                                   MemoryRegion *mr, Error **errp);
-ram_addr_t qemu_ram_alloc(ram_addr_t size, MemoryRegion *mr);
+ram_addr_t qemu_ram_alloc(ram_addr_t size, MemoryRegion *mr, Error **errp);
 int qemu_get_ram_fd(ram_addr_t addr);
 void *qemu_get_ram_block_host_ptr(ram_addr_t addr);
 void *qemu_get_ram_ptr(ram_addr_t addr);

memory.c

@@ -1148,7 +1148,7 @@ void memory_region_init_ram(MemoryRegion *mr,
     mr->ram = true;
     mr->terminates = true;
     mr->destructor = memory_region_destructor_ram;
-    mr->ram_addr = qemu_ram_alloc(size, mr);
+    mr->ram_addr = qemu_ram_alloc(size, mr, &error_abort);
 }
 
 #ifdef __linux__
@@ -1178,7 +1178,10 @@ void memory_region_init_ram_ptr(MemoryRegion *mr,
     mr->ram = true;
     mr->terminates = true;
     mr->destructor = memory_region_destructor_ram_from_ptr;
-    mr->ram_addr = qemu_ram_alloc_from_ptr(size, ptr, mr);
+
+    /* qemu_ram_alloc_from_ptr cannot fail with ptr != NULL.  */
+    assert(ptr != NULL);
+    mr->ram_addr = qemu_ram_alloc_from_ptr(size, ptr, mr, &error_abort);
 }
 
 void memory_region_init_alias(MemoryRegion *mr,
@@ -1208,7 +1211,7 @@ void memory_region_init_rom_device(MemoryRegion *mr,
     mr->terminates = true;
     mr->rom_device = true;
     mr->destructor = memory_region_destructor_rom_device;
-    mr->ram_addr = qemu_ram_alloc(size, mr);
+    mr->ram_addr = qemu_ram_alloc(size, mr, &error_abort);
 }
 
 void memory_region_init_iommu(MemoryRegion *mr,