commit aaa0eb75e2e56d483c89731a447c999985713b43
author Liran Schour <lirans@il.ibm.com> Tue Jan 26 10:31:48 2010 +0200
committer Anthony Liguori <aliguori@us.ibm.com> Tue Feb 09 16:56:14 2010 -0600
tree 1d026f3e2867cabc2e896b82aede646297aee8a6
parent d76cac7dfbff76acb8eac2de849d148b0ff8cbbb

Count dirty blocks and expose an API to get dirty count

This will manage dirty counter for each device and will allow to get the
dirty counter from above.

Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

block.c

diff --git a/block.c b/block.c
index 1919d19..e9fd880 100644
--- a/block.c
+++ b/block.c
@@ -686,9 +686,15 @@
         bit = start % (sizeof(unsigned long) * 8);
         val = bs->dirty_bitmap[idx];
         if (dirty) {
-            val |= 1 << bit;
+            if (!(val & (1 << bit))) {
+                bs->dirty_count++;
+                val |= 1 << bit;
+            }
         } else {
-            val &= ~(1 << bit);
+            if (val & (1 << bit)) {
+                bs->dirty_count--;
+                val &= ~(1 << bit);
+            }
         }
         bs->dirty_bitmap[idx] = val;
     }
@@ -2139,6 +2145,7 @@
 {
     int64_t bitmap_size;
 
+    bs->dirty_count = 0;
     if (enable) {
         if (!bs->dirty_bitmap) {
             bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) +
@@ -2173,3 +2180,8 @@
 {
     set_dirty_bitmap(bs, cur_sector, nr_sectors, 0);
 }
+
+int64_t bdrv_get_dirty_count(BlockDriverState *bs)
+{
+    return bs->dirty_count;
+}