4185 New hash algorithm support

@@ -20,10 +20,11 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
+ * Copyright 2013 Saso Kiselkov. All rights reserved.
  */
 
 #include <sys/zfs_context.h>
 #include <sys/spa_impl.h>
 #include <sys/spa_boot.h>

@@ -47,11 +48,11 @@
 #include <sys/fs/zfs.h>
 #include <sys/metaslab_impl.h>
 #include <sys/arc.h>
 #include <sys/ddt.h>
 #include "zfs_prop.h"
-#include "zfeature_common.h"
+#include <sys/zfeature.h>
 
 /*
  * SPA locking
  *
  * There are four basic locks for managing spa_t structures:

@@ -493,10 +494,11 @@
         mutex_init(&spa->spa_errlist_lock, NULL, MUTEX_DEFAULT, NULL);
         mutex_init(&spa->spa_errlog_lock, NULL, MUTEX_DEFAULT, NULL);
         mutex_init(&spa->spa_history_lock, NULL, MUTEX_DEFAULT, NULL);
         mutex_init(&spa->spa_proc_lock, NULL, MUTEX_DEFAULT, NULL);
         mutex_init(&spa->spa_props_lock, NULL, MUTEX_DEFAULT, NULL);
+        mutex_init(&spa->spa_cksum_tmpls_lock, NULL, MUTEX_DEFAULT, NULL);
         mutex_init(&spa->spa_scrub_lock, NULL, MUTEX_DEFAULT, NULL);
         mutex_init(&spa->spa_suspend_lock, NULL, MUTEX_DEFAULT, NULL);
         mutex_init(&spa->spa_vdev_top_lock, NULL, MUTEX_DEFAULT, NULL);
         mutex_init(&spa->spa_iokstat_lock, NULL, MUTEX_DEFAULT, NULL);
 

@@ -639,10 +641,12 @@
         spa->spa_iokstat = NULL;
 
         for (int t = 0; t < TXG_SIZE; t++)
                 bplist_destroy(&spa->spa_free_bplist[t]);
 
+        zio_checksum_templates_free(spa);
+
         cv_destroy(&spa->spa_async_cv);
         cv_destroy(&spa->spa_proc_cv);
         cv_destroy(&spa->spa_scrub_io_cv);
         cv_destroy(&spa->spa_suspend_cv);
 

@@ -650,10 +654,11 @@
         mutex_destroy(&spa->spa_errlist_lock);
         mutex_destroy(&spa->spa_errlog_lock);
         mutex_destroy(&spa->spa_history_lock);
         mutex_destroy(&spa->spa_proc_lock);
         mutex_destroy(&spa->spa_props_lock);
+        mutex_destroy(&spa->spa_cksum_tmpls_lock);
         mutex_destroy(&spa->spa_scrub_lock);
         mutex_destroy(&spa->spa_suspend_lock);
         mutex_destroy(&spa->spa_vdev_top_lock);
         mutex_destroy(&spa->spa_iokstat_lock);
 

@@ -1780,10 +1785,67 @@
 spa_writeable(spa_t *spa)
 {
         return (!!(spa->spa_mode & FWRITE));
 }
 
+static int
+activate_salted_cksum_check(zfeature_info_t *feature, dmu_tx_t *tx)
+{
+        spa_t   *spa = dmu_tx_pool(tx)->dp_spa;
+
+        if (!spa_feature_is_active(spa, feature))
+                return (0);
+        else
+                return (SET_ERROR(EBUSY));
+}
+
+static void
+activate_salted_cksum_sync(zfeature_info_t *feature, dmu_tx_t *tx)
+{
+        spa_t   *spa = dmu_tx_pool(tx)->dp_spa;
+
+        spa_feature_incr(spa, feature, tx);
+        /*
+         * This is the first salted checksum that's been activated, so
+         * create the persistent checksum salt object now.
+         */
+        if (spa->spa_cksum_salt_obj == 0) {
+                spa->spa_cksum_salt_obj = zap_create_link(spa->spa_meta_objset,
+                    DMU_OTN_ZAP_METADATA, DMU_POOL_DIRECTORY_OBJECT,
+                    DMU_POOL_CHECKSUM_SALT, tx);
+                VERIFY3U(zap_add(spa->spa_meta_objset,
+                    spa->spa_cksum_salt_obj, DMU_POOL_CHECKSUM_SALT, 1,
+                    sizeof (spa->spa_cksum_salt.zcs_bytes),
+                    spa->spa_cksum_salt.zcs_bytes, tx), ==, 0);
+        }
+}
+
+/*
+ * Activates a feature associated with a salted checksum. You must call this
+ * function instead of calling spa_feature_incr() directly, because we may
+ * also need to sync the MOS object holding the checksum salt.
+ * Arguments:
+ *      spa     Pool on which to activate the salted checksum feature.
+ *      feature Salted checksum algorithm feature to activate (see
+ *              spa_feature_table).
+ */
+int
+spa_activate_salted_cksum(spa_t *spa, struct zfeature_info *feature)
+{
+        int err;
+
+        /* EBUSY here indicates that the feature is already active */
+        err = dsl_sync_task(spa_name(spa),
+            (dsl_checkfunc_t *)activate_salted_cksum_check,
+            (dsl_syncfunc_t *)activate_salted_cksum_sync, feature, 2);
+
+        if (err != 0 && err != EBUSY)
+                return (err);
+        else
+                return (0);
+}
+
 int
 spa_mode(spa_t *spa)
 {
         return (spa->spa_mode);
 }