[Qemu-devel] [PATCH v2 3/9] exec: split qemu_ram_alloc_from_file()

["Marc-André Lureau" <marcandre.lureau@redhat.com>]

Add qemu_ram_alloc_from_fd(), which can be use to allocate ramblock from
fd only.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/exec/ram_addr.h |  3 +++
 exec.c                  | 45 ++++++++++++++++++++++++++++++---------------
 2 files changed, 33 insertions(+), 15 deletions(-)

diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 54d7108a9e..7f013fe795 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -98,6 +98,9 @@ void qemu_mutex_unlock_ramlist(void);
 RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
                                    bool share, const char *mem_path,
                                    Error **errp);
+RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
+                                 bool share, int fd,
+                                 Error **errp);
 RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
                                   MemoryRegion *mr, Error **errp);
 RAMBlock *qemu_ram_alloc(ram_addr_t size, MemoryRegion *mr, Error **errp);
diff --git a/exec.c b/exec.c
index b6d52e7c43..fbf02d15d0 100644
--- a/exec.c
+++ b/exec.c
@@ -1674,14 +1674,12 @@ static void ram_block_add(RAMBlock *new_block, Error **errp)
 }
 
 #ifdef __linux__
-RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
-                                   bool share, const char *mem_path,
-                                   Error **errp)
+RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
+                                 bool share, int fd,
+                                 Error **errp)
 {
     RAMBlock *new_block;
     Error *local_err = NULL;
-    int fd;
-    bool created;
     int64_t file_size;
 
     if (xen_enabled()) {
@@ -1706,18 +1704,12 @@ RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
         return NULL;
     }
 
-    fd = file_ram_open(mem_path, memory_region_name(mr), &created, errp);
-    if (fd < 0) {
-        return NULL;
-    }
-
     size = HOST_PAGE_ALIGN(size);
     file_size = get_file_size(fd);
     if (file_size > 0 && file_size < size) {
         error_setg(errp, "backing store %s size 0x%" PRIx64
                    " does not match 'size' option 0x" RAM_ADDR_FMT,
                    mem_path, file_size, size);
-        close(fd);
         return NULL;
     }
 
@@ -1728,10 +1720,6 @@ RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
     new_block->flags = share ? RAM_SHARED : 0;
     new_block->host = file_ram_alloc(new_block, size, fd, !file_size, errp);
     if (!new_block->host) {
-        if (created) {
-            unlink(mem_path);
-        }
-        close(fd);
         g_free(new_block);
         return NULL;
     }
@@ -1743,6 +1731,33 @@ RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
         return NULL;
     }
     return new_block;
+
+}
+
+
+RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
+                                   bool share, const char *mem_path,
+                                   Error **errp)
+{
+    int fd;
+    bool created;
+    RAMBlock *block;
+
+    fd = file_ram_open(mem_path, memory_region_name(mr), &created, errp);
+    if (fd < 0) {
+        return NULL;
+    }
+
+    block = qemu_ram_alloc_from_fd(size, mr, share, fd, errp);
+    if (!block) {
+        if (created) {
+            unlink(mem_path);
+        }
+        close(fd);
+        return NULL;
+    }
+
+    return block;
 }
 #endif
 
-- 
2.11.0