[Qemu-devel] [PATCH v3 16/35] arch_init/ram_load: refactor ram_load

[Isaku Yamahata]

ram_load_page() will be used by postcopy.

Signed-off-by: Isaku Yamahata <address@hidden>
---
Changes v2 -> v3:
- new
---
 arch_init.c |  137 +++++++++++++++++++++++++++++++----------------------------
 arch_init.h |    3 ++
 2 files changed, 74 insertions(+), 66 deletions(-)

diff --git a/arch_init.c b/arch_init.c
index 7e6d84e..c77e24d 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -721,7 +721,7 @@ static int ram_save_complete(QEMUFile *f, void *opaque)
     return 0;
 }
 
-static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host)
+static int load_xbzrle(QEMUFile *f, void *host)
 {
     int ret, rc = 0;
     unsigned int xh_len;
@@ -792,12 +792,73 @@ static inline void *host_from_stream_offset(QEMUFile *f,
     return NULL;
 }
 
+int ram_load_mem_size(QEMUFile *f, ram_addr_t total_ram_bytes)
+{
+    /* Synchronize RAM block list */
+    char id[256];
+    ram_addr_t length;
+
+    while (total_ram_bytes) {
+        RAMBlock *block;
+        uint8_t len;
+
+        len = qemu_get_byte(f);
+        qemu_get_buffer(f, (uint8_t *)id, len);
+        id[len] = 0;
+        length = qemu_get_be64(f);
+
+        QLIST_FOREACH(block, &ram_list.blocks, next) {
+            if (!strncmp(id, block->idstr, sizeof(id))) {
+                if (block->length != length)
+                    return -EINVAL;
+                break;
+            }
+        }
+
+        if (!block) {
+            fprintf(stderr, "Unknown ramblock \"%s\", cannot "
+                    "accept migration\n", id);
+            return -EINVAL;
+        }
+
+        total_ram_bytes -= length;
+    }
+
+    return 0;
+}
+
+int ram_load_page(QEMUFile *f, void *host, int flags)
+{
+    if (flags & RAM_SAVE_FLAG_COMPRESS) {
+        uint8_t ch;
+        ch = qemu_get_byte(f);
+        memset(host, ch, TARGET_PAGE_SIZE);
+#ifndef _WIN32
+        if (ch == 0 &&
+            (!kvm_enabled() || kvm_has_sync_mmu())) {
+            qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED);
+        }
+#endif
+    } else if (flags & RAM_SAVE_FLAG_PAGE) {
+        qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
+    } else if (flags & RAM_SAVE_FLAG_XBZRLE) {
+        if (!migrate_use_xbzrle()) {
+            return -EINVAL;
+        }
+        if (load_xbzrle(f, host) < 0) {
+            return -EINVAL;
+        }
+    }
+    return 0;
+}
+
 static int ram_load(QEMUFile *f, void *opaque, int version_id)
 {
     ram_addr_t addr;
     int flags, ret = 0;
     int error;
     static uint64_t seq_iter;
+    void *host;
 
     seq_iter++;
 
@@ -813,82 +874,26 @@ static int ram_load(QEMUFile *f, void *opaque, int 
version_id)
 
         if (flags & RAM_SAVE_FLAG_MEM_SIZE) {
             if (version_id == 4) {
-                /* Synchronize RAM block list */
-                char id[256];
-                ram_addr_t length;
-                ram_addr_t total_ram_bytes = addr;
-
-                while (total_ram_bytes) {
-                    RAMBlock *block;
-                    uint8_t len;
-
-                    len = qemu_get_byte(f);
-                    qemu_get_buffer(f, (uint8_t *)id, len);
-                    id[len] = 0;
-                    length = qemu_get_be64(f);
-
-                    QLIST_FOREACH(block, &ram_list.blocks, next) {
-                        if (!strncmp(id, block->idstr, sizeof(id))) {
-                            if (block->length != length) {
-                                ret =  -EINVAL;
-                                goto done;
-                            }
-                            break;
-                        }
-                    }
-
-                    if (!block) {
-                        fprintf(stderr, "Unknown ramblock \"%s\", cannot "
-                                "accept migration\n", id);
-                        ret = -EINVAL;
-                        goto done;
-                    }
-
-                    total_ram_bytes -= length;
+                error = ram_load_mem_size(f, addr);
+                if (error) {
+                    DPRINTF("error %d\n", error);
+                    return error;
                 }
             }
         }
 
-        if (flags & RAM_SAVE_FLAG_COMPRESS) {
-            void *host;
-            uint8_t ch;
-
-            host = host_from_stream_offset(f, addr, flags);
-            if (!host) {
-                return -EINVAL;
-            }
-
-            ch = qemu_get_byte(f);
-            memset(host, ch, TARGET_PAGE_SIZE);
-#ifndef _WIN32
-            if (ch == 0 &&
-                (!kvm_enabled() || kvm_has_sync_mmu())) {
-                qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED);
-            }
-#endif
-        } else if (flags & RAM_SAVE_FLAG_PAGE) {
-            void *host;
-
+        if (flags & (RAM_SAVE_FLAG_COMPRESS | RAM_SAVE_FLAG_PAGE |
+                     RAM_SAVE_FLAG_XBZRLE)) {
             host = host_from_stream_offset(f, addr, flags);
             if (!host) {
                 return -EINVAL;
             }
-
-            qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
-        } else if (flags & RAM_SAVE_FLAG_XBZRLE) {
-            if (!migrate_use_xbzrle()) {
-                return -EINVAL;
-            }
-            void *host = host_from_stream_offset(f, addr, flags);
-            if (!host) {
-                return -EINVAL;
-            }
-
-            if (load_xbzrle(f, addr, host) < 0) {
-                ret = -EINVAL;
+            ret = ram_load_page(f, host, flags);
+            if (ret) {
                 goto done;
             }
         }
+
         error = qemu_file_get_error(f);
         if (error) {
             ret = error;
diff --git a/arch_init.h b/arch_init.h
index f2a7ae5..bca1a29 100644
--- a/arch_init.h
+++ b/arch_init.h
@@ -46,9 +46,12 @@ CpuDefinitionInfoList GCC_WEAK_DECL 
*arch_query_cpu_definitions(Error **errp);
 
 #define RAM_SAVE_VERSION_ID     4 /* currently version 4 */
 
+int ram_load_page(QEMUFile *f, void *host, int flags);
+
 #if defined(NEED_CPU_H) && !defined(CONFIG_USER_ONLY)
 bool ram_save_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset,
                    bool last_stage);
+int ram_load_mem_size(QEMUFile *f, ram_addr_t total_ram_bytes);
 #endif
 
 #endif
-- 
1.7.10.4