[Qemu-devel] [PATCH 1/6] split dirty bitmap into four for dumping the bitmaps

[Sanidhya Kashyap <sanidhya.iiith@gmail.com>]

Added another flag - DIRTY_MEMORY_LOG_BITMAP for the purpose of logging
the dirty bitmap. The dumping bitmap process will utilize this flag for
dumping the data in the file.

Signed-off-by: Sanidhya Kashyap <sanidhya.iiith@gmail.com>
---
 exec.c                  |  4 ++++
 include/exec/memory.h   |  3 ++-
 include/exec/ram_addr.h | 16 +++++++++++++++-
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/exec.c b/exec.c
index 4e179a6..658196c 100644
--- a/exec.c
+++ b/exec.c
@@ -1551,6 +1551,7 @@ static void notdirty_mem_write(void *opaque, hwaddr ram_addr,
     }
     cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_MIGRATION);
     cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_VGA);
+    cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_LOG_BITMAP);
     /* we remove the notdirty callback only if the code has been
        flushed */
     if (!cpu_physical_memory_is_clean(ram_addr)) {
@@ -1959,6 +1960,7 @@ static void invalidate_and_set_dirty(hwaddr addr,
         /* set dirty bit */
         cpu_physical_memory_set_dirty_flag(addr, DIRTY_MEMORY_VGA);
         cpu_physical_memory_set_dirty_flag(addr, DIRTY_MEMORY_MIGRATION);
+        cpu_physical_memory_set_dirty_flag(addr, DIRTY_MEMORY_LOG_BITMAP);
     }
     xen_modified_memory(addr, length);
 }
@@ -2563,6 +2565,8 @@ void stl_phys_notdirty(AddressSpace *as, hwaddr addr, uint32_t val)
                 cpu_physical_memory_set_dirty_flag(addr1,
                                                    DIRTY_MEMORY_MIGRATION);
                 cpu_physical_memory_set_dirty_flag(addr1, DIRTY_MEMORY_VGA);
+                cpu_physical_memory_set_dirty_flag(addr1,
+                                                   DIRTY_MEMORY_LOG_BITMAP);
             }
         }
     }
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 1d55ad9..3f24563 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -19,7 +19,8 @@
 #define DIRTY_MEMORY_VGA       0
 #define DIRTY_MEMORY_CODE      1
 #define DIRTY_MEMORY_MIGRATION 2
-#define DIRTY_MEMORY_NUM       3        /* num of dirty bits */
+#define DIRTY_MEMORY_LOG_BITMAP 3
+#define DIRTY_MEMORY_NUM       4        /* num of dirty bits */
 
 #include <stdint.h>
 #include <stdbool.h>
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 2edfa96..f1ca86f 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -56,7 +56,10 @@ static inline bool cpu_physical_memory_is_clean(ram_addr_t addr)
     bool code = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_CODE);
     bool migration =
         cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_MIGRATION);
-    return !(vga && code && migration);
+    bool bitmap_log =
+        cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_LOG_BITMAP);
+
+    return !(vga && code && migration && bitmap_log);
 }
 
 static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
@@ -66,6 +69,13 @@ static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
     set_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
 }
 
+static inline void cpu_physical_memory_clear_dirty_flag(ram_addr_t addr,
+                                                        unsigned client)
+{
+    assert(client < DIRTY_MEMORY_NUM);
+    clear_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
+}
+
 static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
                                                        ram_addr_t length)
 {
@@ -76,6 +86,8 @@ static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
     bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION], page, end - page);
     bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_VGA], page, end - page);
     bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_CODE], page, end - page);
+    bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_LOG_BITMAP], page,
+                                                               end - page);
     xen_modified_memory(start, length);
 }
 
@@ -105,6 +117,8 @@ static inline void cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
                 ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION][page + k] |= temp;
                 ram_list.dirty_memory[DIRTY_MEMORY_VGA][page + k] |= temp;
                 ram_list.dirty_memory[DIRTY_MEMORY_CODE][page + k] |= temp;
+                ram_list.dirty_memory[DIRTY_MEMORY_LOG_BITMAP][page + k] |=
+                                                                        temp;
             }
         }
         xen_modified_memory(start, pages);
-- 
1.8.3.1