[Qemu-devel] [PULL 06/57] qemu_ram_block_by_name

[Juan Quintela <quintela@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Add a function to find a RAMBlock by name; use it in two
of the places that already open code that loop; we've
got another use later in postcopy.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 exec.c                    | 20 ++++++++++++++++++++
 include/exec/cpu-common.h |  1 +
 migration/ram.c           | 35 +++++++++++++++--------------------
 3 files changed, 36 insertions(+), 20 deletions(-)

diff --git a/exec.c b/exec.c
index 53d3848..36886ee 100644
--- a/exec.c
+++ b/exec.c
@@ -1946,6 +1946,26 @@ found:
     return block;
 }

+/*
+ * Finds the named RAMBlock
+ *
+ * name: The name of RAMBlock to find
+ *
+ * Returns: RAMBlock (or NULL if not found)
+ */
+RAMBlock *qemu_ram_block_by_name(const char *name)
+{
+    RAMBlock *block;
+
+    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+        if (!strcmp(name, block->idstr)) {
+            return block;
+        }
+    }
+
+    return NULL;
+}
+
 /* Some of the softmmu routines need to translate from a host pointer
    (typically a TLB entry) back to a ram offset.  */
 MemoryRegion *qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
index 94d1f8a..85aa403 100644
--- a/include/exec/cpu-common.h
+++ b/include/exec/cpu-common.h
@@ -64,6 +64,7 @@ typedef uint32_t CPUReadMemoryFunc(void *opaque, hwaddr addr);
 void qemu_ram_remap(ram_addr_t addr, ram_addr_t length);
 /* This should not be used by devices.  */
 MemoryRegion *qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr);
+RAMBlock *qemu_ram_block_by_name(const char *name);
 RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset,
                                    ram_addr_t *ram_addr, ram_addr_t *offset);
 void qemu_ram_set_idstr(ram_addr_t addr, const char *name, DeviceState *dev);
diff --git a/migration/ram.c b/migration/ram.c
index df3df9e..d654a73 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -1420,14 +1420,12 @@ static inline void *host_from_stream_offset(QEMUFile *f,
     qemu_get_buffer(f, (uint8_t *)id, len);
     id[len] = 0;

-    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
-        if (!strncmp(id, block->idstr, sizeof(id)) &&
-            block->max_length > offset) {
-            return block->host + offset;
-        }
+    block = qemu_ram_block_by_name(id);
+    if (block && block->max_length > offset) {
+        return block->host + offset;
     }

-    error_report("Can't find block %s!", id);
+    error_report("Can't find block %s", id);
     return NULL;
 }

@@ -1576,23 +1574,20 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
                 id[len] = 0;
                 length = qemu_get_be64(f);

-                QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
-                    if (!strncmp(id, block->idstr, sizeof(id))) {
-                        if (length != block->used_length) {
-                            Error *local_err = NULL;
+                block = qemu_ram_block_by_name(id);
+                if (block) {
+                    if (length != block->used_length) {
+                        Error *local_err = NULL;

-                            ret = qemu_ram_resize(block->offset, length, &local_err);
-                            if (local_err) {
-                                error_report_err(local_err);
-                            }
+                        ret = qemu_ram_resize(block->offset, length,
+                                              &local_err);
+                        if (local_err) {
+                            error_report_err(local_err);
                         }
-                        ram_control_load_hook(f, RAM_CONTROL_BLOCK_REG,
-                                              block->idstr);
-                        break;
                     }
-                }
-
-                if (!block) {
+                    ram_control_load_hook(f, RAM_CONTROL_BLOCK_REG,
+                                          block->idstr);
+                } else {
                     error_report("Unknown ramblock \"%s\", cannot "
                                  "accept migration", id);
                     ret = -EINVAL;
-- 
2.5.0