Illumos #4101, #4102, #4103, #4105, #4106

[mirror_zfs.git] / module / zfs / zfeature.c

diff --git a/module/zfs/zfeature.c b/module/zfs/zfeature.c
index 4f4785a0c82a1ec04e62d5857fbff699cc9b4b21..cdb9d6dce2a7c32b8894e48c75c5ddd5ab56676d 100644 (file)
--- a/module/zfs/zfeature.c
+++ b/module/zfs/zfeature.c
@@ -369,36 +369,46 @@ spa_feature_enable(spa_t *spa, zfeature_info_t *feature, dmu_tx_t *tx)
            spa->spa_feat_desc_obj, feature, FEATURE_ACTION_ENABLE, tx));
 }
 
-/*
- * If the specified feature has not yet been enabled, this function returns
- * ENOTSUP; otherwise, this function increments the feature's refcount (or
- * returns EOVERFLOW if the refcount cannot be incremented). This function must
- * be called from syncing context.
- */
 void
 spa_feature_incr(spa_t *spa, zfeature_info_t *feature, dmu_tx_t *tx)
 {
+       ASSERT(dmu_tx_is_syncing(tx));
        ASSERT3U(spa_version(spa), >=, SPA_VERSION_FEATURES);
        VERIFY3U(0, ==, feature_do_action(spa->spa_meta_objset,
            spa->spa_feat_for_read_obj, spa->spa_feat_for_write_obj,
            spa->spa_feat_desc_obj, feature, FEATURE_ACTION_INCR, tx));
 }
 
-/*
- * If the specified feature has not yet been enabled, this function returns
- * ENOTSUP; otherwise, this function decrements the feature's refcount (or
- * returns EOVERFLOW if the refcount is already 0). This function must
- * be called from syncing context.
- */
 void
 spa_feature_decr(spa_t *spa, zfeature_info_t *feature, dmu_tx_t *tx)
 {
+       ASSERT(dmu_tx_is_syncing(tx));
        ASSERT3U(spa_version(spa), >=, SPA_VERSION_FEATURES);
        VERIFY3U(0, ==, feature_do_action(spa->spa_meta_objset,
            spa->spa_feat_for_read_obj, spa->spa_feat_for_write_obj,
            spa->spa_feat_desc_obj, feature, FEATURE_ACTION_DECR, tx));
 }
 
+/*
+ * This interface is for debugging only. Normal consumers should use
+ * spa_feature_is_enabled/spa_feature_is_active.
+ */
+int
+spa_feature_get_refcount(spa_t *spa, zfeature_info_t *feature)
+{
+       int err;
+       uint64_t refcount = 0;
+
+       if (spa_version(spa) < SPA_VERSION_FEATURES)
+               return (B_FALSE);
+
+       err = feature_get_refcount(spa->spa_meta_objset,
+           spa->spa_feat_for_read_obj, spa->spa_feat_for_write_obj,
+           feature, &refcount);
+       ASSERT(err == 0 || err == ENOTSUP);
+       return (err == 0 ? refcount : 0);
+}
+
 boolean_t
 spa_feature_is_enabled(spa_t *spa, zfeature_info_t *feature)
 {