4 files changed, 49 insertions, 11 deletions

diff --git a/exec.c b/exec.c
index 4ced1a6..53d3848 100644
--- a/exec.c
+++ b/exec.c
@@ -1377,6 +1377,11 @@ static RAMBlock *find_ram_block(ram_addr_t addr)
     return NULL;
 }
 
+const char *qemu_ram_get_idstr(RAMBlock *rb)
+{
+    return rb->idstr;
+}
+
 /* Called with iothread lock held.  */
 void qemu_ram_set_idstr(ram_addr_t addr, const char *name, DeviceState *dev)
 {
@@ -1877,8 +1882,16 @@ static void *qemu_ram_ptr_length(ram_addr_t addr, hwaddr *size)
     }
 }
 
-/* Some of the softmmu routines need to translate from a host pointer
- * (typically a TLB entry) back to a ram offset.
+/*
+ * Translates a host ptr back to a RAMBlock, a ram_addr and an offset
+ * in that RAMBlock.
+ *
+ * ptr: Host pointer to look up
+ * round_offset: If true round the result offset down to a page boundary
+ * *ram_addr: set to result ram_addr
+ * *offset: set to result offset within the RAMBlock
+ *
+ * Returns: RAMBlock (or NULL if not found)
  *
  * By the time this function returns, the returned pointer is not protected
  * by RCU anymore.  If the caller is not within an RCU critical section and
@@ -1886,18 +1899,22 @@ static void *qemu_ram_ptr_length(ram_addr_t addr, hwaddr *size)
  * pointer, such as a reference to the region that includes the incoming
  * ram_addr_t.
  */
-MemoryRegion *qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
+RAMBlock *qemu_ram_block_from_host(void *ptr, bool round_offset,
+                                   ram_addr_t *ram_addr,
+                                   ram_addr_t *offset)
 {
     RAMBlock *block;
     uint8_t *host = ptr;
-    MemoryRegion *mr;
 
     if (xen_enabled()) {
         rcu_read_lock();
         *ram_addr = xen_ram_addr_from_mapcache(ptr);
-        mr = qemu_get_ram_block(*ram_addr)->mr;
+        block = qemu_get_ram_block(*ram_addr);
+        if (block) {
+            *offset = (host - block->host);
+        }
         rcu_read_unlock();
-        return mr;
+        return block;
     }
 
     rcu_read_lock();
@@ -1920,10 +1937,29 @@ MemoryRegion *qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
     return NULL;
 
 found:
-    *ram_addr = block->offset + (host - block->host);
-    mr = block->mr;
+    *offset = (host - block->host);
+    if (round_offset) {
+        *offset &= TARGET_PAGE_MASK;
+    }
+    *ram_addr = block->offset + *offset;
     rcu_read_unlock();
-    return mr;
+    return block;
+}
+
+/* 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)
+{
+    RAMBlock *block;
+    ram_addr_t offset; /* Not used */
+
+    block = qemu_ram_block_from_host(ptr, false, ram_addr, &offset);
+
+    if (!block) {
+        return NULL;
+    }
+
+    return block->mr;
 }
 
 static void notdirty_mem_write(void *opaque, hwaddr ram_addr,
diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
index 9fb1d54..94d1f8a 100644
--- a/include/exec/cpu-common.h
+++ b/include/exec/cpu-common.h
@@ -64,8 +64,11 @@ 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_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);
 void qemu_ram_unset_idstr(ram_addr_t addr);
+const char *qemu_ram_get_idstr(RAMBlock *rb);
 
 void cpu_physical_memory_rw(hwaddr addr, uint8_t *buf,
                             int len, int is_write);
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 3360ac5..7115154 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -22,8 +22,6 @@
 #ifndef CONFIG_USER_ONLY
 #include "hw/xen/xen.h"
 
-typedef struct RAMBlock RAMBlock;
-
 struct RAMBlock {
     struct rcu_head rcu;
     struct MemoryRegion *mr;
diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
index 2cdce18..4338767 100644
--- a/include/qemu/typedefs.h
+++ b/include/qemu/typedefs.h
@@ -79,6 +79,7 @@ typedef struct QEMUSizedBuffer QEMUSizedBuffer;
 typedef struct QEMUTimerListGroup QEMUTimerListGroup;
 typedef struct QEMUTimer QEMUTimer;
 typedef struct Range Range;
+typedef struct RAMBlock RAMBlock;
 typedef struct SerialState SerialState;
 typedef struct SHPCDevice SHPCDevice;
 typedef struct SMBusDevice SMBusDevice;