Fix missing parity chunk calculation for EC n+k, k > 1 and first parity chunk missing

src/osd_rmw.cpp

@@ -759,7 +759,18 @@ static void calc_rmw_parity_copy_mod(osd_rmw_stripe_t *stripes, int pg_size, int
     uint64_t *read_osd_set, uint64_t *write_osd_set, uint32_t chunk_size, uint32_t bitmap_granularity,
     uint32_t &start, uint32_t &end)
 {
-    if (write_osd_set[pg_minsize] != 0 || write_osd_set != read_osd_set)
+    bool required = false;
+    for (int role = pg_minsize; role < pg_size; role++)
+    {
+        if (write_osd_set[role] != 0)
+        {
+            // Whole parity chunk is needed when we move the object
+            if (write_osd_set[role] != read_osd_set[role])
+                end = chunk_size;
+            required = true;
+        }
+    }
+    if (required && end != chunk_size)
     {
         // start & end are required for calc_rmw_parity
         for (int role = 0; role < pg_minsize; role++)
@@ -770,14 +781,6 @@ static void calc_rmw_parity_copy_mod(osd_rmw_stripe_t *stripes, int pg_size, int
                 end = std::max(stripes[role].req_end, end);
             }
         }
-        for (int role = pg_minsize; role < pg_size; role++)
-        {
-            if (write_osd_set[role] != 0 && write_osd_set[role] != read_osd_set[role])
-            {
-                start = 0;
-                end = chunk_size;
-            }
-        }
     }
     // Set bitmap bits accordingly
     if (bitmap_granularity > 0)

src/osd_rmw_test.cpp

@@ -24,7 +24,7 @@ void test11();
 void test12();
 void test13();
 void test14();
-void test15();
+void test15(bool second);
 void test16();
 
 int main(int narg, char *args[])
@@ -54,7 +54,8 @@ int main(int narg, char *args[])
     // Test 14
     test14();
     // Test 15
-    test15();
+    test15(false);
+    test15(true);
     // Test 16
     test16();
     // End
@@ -826,12 +827,11 @@ void test14()
 
 ***/
 
-void test15()
+void test15(bool second)
 {
     const int bmp = 64*1024 / 4096 / 8;
     use_ec(4, 2, true);
-    osd_num_t osd_set[4] = { 1, 2, 3, 0 };
-    osd_num_t write_osd_set[4] = { 1, 2, 3, 0 };
+    osd_num_t osd_set[4] = { 1, 2, (osd_num_t)(second ? 0 : 3), (osd_num_t)(second ? 4 : 0) };
     osd_rmw_stripe_t stripes[4] = {};
     unsigned bitmaps[4] = { 0 };
     // Test 15.0
@@ -842,7 +842,7 @@ void test15()
     assert(stripes[2].req_start == 0 && stripes[2].req_end == 0);
     assert(stripes[3].req_start == 0 && stripes[3].req_end == 0);
     // Test 15.1
-    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 4, 2, 3, write_osd_set, 64*1024, bmp);
+    void *rmw_buf = calc_rmw(write_buf, stripes, osd_set, 4, 2, 3, osd_set, 64*1024, bmp);
     for (int i = 0; i < 4; i++)
         stripes[i].bmp_buf = bitmaps+i;
     assert(rmw_buf);
@@ -852,32 +852,34 @@ void test15()
     assert(stripes[3].read_start == 0 && stripes[3].read_end == 0);
     assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
     assert(stripes[1].write_start == 28*1024 && stripes[1].write_end == 32*1024);
-    assert(stripes[2].write_start == 28*1024 && stripes[2].write_end == 32*1024);
-    assert(stripes[3].write_start == 0 && stripes[3].write_end == 0);
+    assert(stripes[2+second].write_start == 28*1024 && stripes[2+second].write_end == 32*1024);
+    assert(stripes[3-second].write_start == 0 && stripes[3-second].write_end == 0);
     assert(stripes[0].read_buf == (uint8_t*)rmw_buf+4*1024);
     assert(stripes[1].read_buf == NULL);
     assert(stripes[2].read_buf == NULL);
     assert(stripes[3].read_buf == NULL);
     assert(stripes[0].write_buf == NULL);
     assert(stripes[1].write_buf == (uint8_t*)write_buf);
-    assert(stripes[2].write_buf == rmw_buf);
-    assert(stripes[3].write_buf == NULL);
+    assert(stripes[2+second].write_buf == rmw_buf);
+    assert(stripes[3-second].write_buf == NULL);
     // Test 15.2 - encode
     set_pattern(write_buf, 4*1024, PATTERN1);
     set_pattern(stripes[0].read_buf, 4*1024, PATTERN2);
     memset(stripes[0].bmp_buf, 0, bmp);
     memset(stripes[1].bmp_buf, 0, bmp);
-    calc_rmw_parity_ec(stripes, 4, 2, osd_set, write_osd_set, 64*1024, bmp);
-    assert(*(uint32_t*)stripes[2].bmp_buf == 0x80);
+    memset(stripes[2+second].write_buf, 0, 4096);
+    calc_rmw_parity_ec(stripes, 4, 2, osd_set, osd_set, 64*1024, bmp);
+    assert(second || *(uint32_t*)stripes[2].bmp_buf == 0x80);
     assert(stripes[0].write_start == 0 && stripes[0].write_end == 0);
     assert(stripes[1].write_start == 28*1024 && stripes[1].write_end == 32*1024);
-    assert(stripes[2].write_start == 28*1024 && stripes[2].write_end == 32*1024);
-    assert(stripes[3].write_start == 0 && stripes[3].write_end == 0);
+    assert(stripes[2+second].write_start == 28*1024 && stripes[2+second].write_end == 32*1024);
+    assert(stripes[3-second].write_start == 0 && stripes[3-second].write_end == 0);
     assert(stripes[0].write_buf == NULL);
     assert(stripes[1].write_buf == (uint8_t*)write_buf);
-    assert(stripes[2].write_buf == rmw_buf);
-    assert(stripes[3].write_buf == NULL);
-    check_pattern(stripes[2].write_buf, 4*1024, PATTERN1^PATTERN2); // first parity is always xor :)
+    assert(stripes[2+second].write_buf == rmw_buf);
+    assert(stripes[3-second].write_buf == NULL);
+    // first parity is always xor :), second isn't...
+    check_pattern(stripes[2+second].write_buf, 4*1024, second ? 0xb79a59a0ce8b9b81 : PATTERN1^PATTERN2);
     // Done
     free(rmw_buf);
     free(write_buf);