1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/dmu.h> 29 #include <sys/dmu_tx.h> 30 #include <sys/dsl_pool.h> 31 #include <sys/dsl_dir.h> 32 #include <sys/dsl_synctask.h> 33 #include <sys/cred.h> 34 35 #define DST_AVG_BLKSHIFT 14 36 37 /* ARGSUSED */ 38 static int 39 dsl_null_checkfunc(void *arg1, void *arg2, dmu_tx_t *tx) 40 { 41 return (0); 42 } 43 44 dsl_sync_task_group_t * 45 dsl_sync_task_group_create(dsl_pool_t *dp) 46 { 47 dsl_sync_task_group_t *dstg; 48 49 dstg = kmem_zalloc(sizeof (dsl_sync_task_group_t), KM_SLEEP); 50 list_create(&dstg->dstg_tasks, sizeof (dsl_sync_task_t), 51 offsetof(dsl_sync_task_t, dst_node)); 52 dstg->dstg_pool = dp; 53 54 return (dstg); 55 } 56 57 void 58 dsl_sync_task_create(dsl_sync_task_group_t *dstg, 59 dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc, 60 void *arg1, void *arg2, int blocks_modified) 61 { 62 dsl_sync_task_t *dst; 63 64 if (checkfunc == NULL) 65 checkfunc = dsl_null_checkfunc; 66 dst = kmem_zalloc(sizeof (dsl_sync_task_t), KM_SLEEP); 67 dst->dst_checkfunc = checkfunc; 68 dst->dst_syncfunc = syncfunc; 69 dst->dst_arg1 = arg1; 70 dst->dst_arg2 = arg2; 71 dst->dst_cr = CRED(); 72 list_insert_tail(&dstg->dstg_tasks, dst); 73 74 dstg->dstg_space += blocks_modified << DST_AVG_BLKSHIFT; 75 } 76 77 int 78 dsl_sync_task_group_wait(dsl_sync_task_group_t *dstg) 79 { 80 dmu_tx_t *tx; 81 uint64_t txg; 82 dsl_sync_task_t *dst; 83 84 top: 85 tx = dmu_tx_create_dd(dstg->dstg_pool->dp_mos_dir); 86 VERIFY(0 == dmu_tx_assign(tx, TXG_WAIT)); 87 88 txg = dmu_tx_get_txg(tx); 89 90 /* Do a preliminary error check. */ 91 dstg->dstg_err = 0; 92 rw_enter(&dstg->dstg_pool->dp_config_rwlock, RW_READER); 93 for (dst = list_head(&dstg->dstg_tasks); dst; 94 dst = list_next(&dstg->dstg_tasks, dst)) { 95 #ifdef ZFS_DEBUG 96 /* 97 * Only check half the time, otherwise, the sync-context 98 * check will almost never fail. 99 */ 100 if (spa_get_random(2) == 0) 101 continue; 102 #endif 103 dst->dst_err = 104 dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx); 105 if (dst->dst_err) 106 dstg->dstg_err = dst->dst_err; 107 } 108 rw_exit(&dstg->dstg_pool->dp_config_rwlock); 109 110 if (dstg->dstg_err) { 111 dmu_tx_commit(tx); 112 return (dstg->dstg_err); 113 } 114 115 VERIFY(0 == txg_list_add(&dstg->dstg_pool->dp_sync_tasks, dstg, txg)); 116 117 dmu_tx_commit(tx); 118 119 txg_wait_synced(dstg->dstg_pool, txg); 120 121 if (dstg->dstg_err == EAGAIN) 122 goto top; 123 124 return (dstg->dstg_err); 125 } 126 127 void 128 dsl_sync_task_group_destroy(dsl_sync_task_group_t *dstg) 129 { 130 dsl_sync_task_t *dst; 131 132 while (dst = list_head(&dstg->dstg_tasks)) { 133 list_remove(&dstg->dstg_tasks, dst); 134 kmem_free(dst, sizeof (dsl_sync_task_t)); 135 } 136 kmem_free(dstg, sizeof (dsl_sync_task_group_t)); 137 } 138 139 void 140 dsl_sync_task_group_sync(dsl_sync_task_group_t *dstg, dmu_tx_t *tx) 141 { 142 dsl_sync_task_t *dst; 143 void *tr_cookie; 144 145 ASSERT3U(dstg->dstg_err, ==, 0); 146 147 /* 148 * Check for sufficient space. 149 */ 150 dstg->dstg_err = dsl_dir_tempreserve_space(dstg->dstg_pool->dp_mos_dir, 151 dstg->dstg_space, dstg->dstg_space * 3, 0, &tr_cookie, tx); 152 /* don't bother trying again */ 153 if (dstg->dstg_err == ERESTART) 154 dstg->dstg_err = EAGAIN; 155 if (dstg->dstg_err) 156 return; 157 158 /* 159 * Check for errors by calling checkfuncs. 160 */ 161 rw_enter(&dstg->dstg_pool->dp_config_rwlock, RW_WRITER); 162 for (dst = list_head(&dstg->dstg_tasks); dst; 163 dst = list_next(&dstg->dstg_tasks, dst)) { 164 dst->dst_err = 165 dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx); 166 if (dst->dst_err) 167 dstg->dstg_err = dst->dst_err; 168 } 169 170 if (dstg->dstg_err == 0) { 171 /* 172 * Execute sync tasks. 173 */ 174 for (dst = list_head(&dstg->dstg_tasks); dst; 175 dst = list_next(&dstg->dstg_tasks, dst)) { 176 dst->dst_syncfunc(dst->dst_arg1, dst->dst_arg2, 177 dst->dst_cr, tx); 178 } 179 } 180 rw_exit(&dstg->dstg_pool->dp_config_rwlock); 181 182 dsl_dir_tempreserve_clear(tr_cookie, tx); 183 } 184 185 int 186 dsl_sync_task_do(dsl_pool_t *dp, 187 dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc, 188 void *arg1, void *arg2, int blocks_modified) 189 { 190 dsl_sync_task_group_t *dstg; 191 int err; 192 193 dstg = dsl_sync_task_group_create(dp); 194 dsl_sync_task_create(dstg, checkfunc, syncfunc, 195 arg1, arg2, blocks_modified); 196 err = dsl_sync_task_group_wait(dstg); 197 dsl_sync_task_group_destroy(dstg); 198 return (err); 199 } 200