ec: Fixed coverity scan issues

CID list:

  1226163 Logically dead code
  1226166 Missing break in switch
  1226167 Missing break in switch
  1226168 Missing break in switch
  1226169 Missing break in switch
  1226170 Missing break in switch
  1226171 Missing break in switch
  1226172 Missing break in switch
  1226173 Missing break in switch
  1226174 Missing break in switch
  1226175 Missing break in switch
  1226176 Missing break in switch
  1226177 Missing break in switch
  1226178 Data race condition
  1226179 Data race condition
  1226180 Data race condition
  1226181 Thread deadlock
  1226182 Uninitialized pointer read
  1226183 Uninitialized pointer read
  1226184 Read from pointer after free

Change-Id: I4d33aa42289371927175c43bb29e018df64fb943
BUG: 1122834
Signed-off-by: Xavier Hernandez <xhernandez@datalab.es>
Reviewed-on: http://review.gluster.org/8372
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 34 insertions, 28 deletions

diff --git a/xlators/cluster/ec/src/ec-heal.c b/xlators/cluster/ec/src/ec-heal.c
index fe18a0b5f1e..f6ee0076373 100644
--- a/xlators/cluster/ec/src/ec-heal.c
+++ b/xlators/cluster/ec/src/ec-heal.c
@@ -91,6 +91,10 @@ void ec_heal_lookup_resume(ec_fop_data_t * fop)
         }
     }
 
+    /* Heal lookups are not executed concurrently with anything else. So, when
+     * a lookup finishes, it's safe to access heal->good and heal->bad without
+     * acquiring any lock.
+     */
     heal->good = good;
     heal->bad = bad;
 
@@ -456,43 +460,20 @@ int32_t ec_heal_init(ec_fop_data_t * fop)
         return ENODATA;
     }
 
-    LOCK(&inode->lock);
-
-    ctx = __ec_inode_get(inode, fop->xl);
-    if (ctx == NULL)
-    {
-        error = EIO;
-
-        goto out;
-    }
-
-    if (ctx->heal != NULL)
-    {
-        error = EEXIST;
-
-        goto out;
-    }
-
     heal = GF_MALLOC(sizeof(ec_heal_t), ec_mt_ec_heal_t);
     if (heal == NULL)
     {
-        error = ENOMEM;
-
-        goto out;
+        return ENOMEM;
     }
 
     memset(heal, 0, sizeof(ec_heal_t));
 
-    if (loc_copy(&heal->loc, &fop->loc[0]) != 0)
+    if (!ec_loc_from_loc(fop->xl, &heal->loc, &fop->loc[0]))
     {
         error = ENOMEM;
 
         goto out;
     }
-    if (uuid_is_null(heal->loc.gfid))
-    {
-        uuid_copy(heal->loc.gfid, heal->loc.inode->gfid);
-    }
 
     LOCK_INIT(&heal->lock);
 
@@ -501,14 +482,31 @@ int32_t ec_heal_init(ec_fop_data_t * fop)
     pool = fop->xl->ctx->iobuf_pool;
     heal->size = iobpool_default_pagesize(pool) * ec->fragments;
 
+    LOCK(&inode->lock);
+
+    ctx = __ec_inode_get(inode, fop->xl);
+    if (ctx == NULL)
+    {
+        error = EIO;
+
+        goto unlock;
+    }
+
+    if (ctx->heal != NULL)
+    {
+        error = EEXIST;
+
+        goto unlock;
+    }
+
     fop->data = heal;
 
     ctx->heal = heal;
     heal = NULL;
 
-out:
+unlock:
     UNLOCK(&inode->lock);
-
+out:
     GF_FREE(heal);
 
     return error;
@@ -943,6 +941,10 @@ int32_t ec_heal_needs_data_rebuild(ec_heal_t * heal)
         }
     }
 
+    /* This function can only be called concurrently with entrylk, which do
+     * not modify heal structure, so it's safe to access heal->bad without
+     * acquiring any lock.
+     */
     heal->bad = bad;
 
     return (bad != 0);
@@ -1122,7 +1124,7 @@ void ec_heal_dispatch(ec_heal_t * heal)
 
     GF_FREE(heal);
 
-    ec_fop_set_error(heal->fop, error);
+    ec_fop_set_error(fop, error);
 }
 
 void ec_wind_heal(ec_t * ec, ec_fop_data_t * fop, int32_t idx)
@@ -1162,6 +1164,8 @@ int32_t ec_manager_heal(ec_fop_data_t * fop, int32_t state)
                 return EC_STATE_REPORT;
             }
 
+        /* Fall through */
+
         case EC_STATE_DISPATCH:
             ec_heal_entrylk(fop->data, ENTRYLK_LOCK);
 
@@ -1222,6 +1226,8 @@ int32_t ec_manager_heal(ec_fop_data_t * fop, int32_t state)
         case EC_STATE_HEAL_UNLOCK:
             ec_heal_inodelk(heal, F_UNLCK, 0, 0, 0);
 
+        /* Fall through */
+
         case -EC_STATE_HEAL_ENTRY_PREPARE:
         case -EC_STATE_HEAL_PRE_INODELK_LOCK:
         case -EC_STATE_HEAL_PRE_INODE_LOOKUP: