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 2010 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #include <sys/dmu.h> 27 #include <sys/dmu_tx.h> 28 #include <sys/dsl_pool.h> 29 #include <sys/dsl_dir.h> 30 #include <sys/dsl_synctask.h> 31 #include <sys/cred.h> 32 33 #define DST_AVG_BLKSHIFT 14 34 35 /* ARGSUSED */ 36 static int 37 dsl_null_checkfunc(void *arg1, void *arg2, dmu_tx_t *tx) 38 { 39 return (0); 40 } 41 42 dsl_sync_task_group_t * 43 dsl_sync_task_group_create(dsl_pool_t *dp) 44 { 45 dsl_sync_task_group_t *dstg; 46 47 dstg = kmem_zalloc(sizeof (dsl_sync_task_group_t), KM_SLEEP); 48 list_create(&dstg->dstg_tasks, sizeof (dsl_sync_task_t), 49 offsetof(dsl_sync_task_t, dst_node)); 50 dstg->dstg_pool = dp; 51 dstg->dstg_cr = CRED(); 52 53 return (dstg); 54 } 55 56 void 57 dsl_sync_task_create(dsl_sync_task_group_t *dstg, 58 dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc, 59 void *arg1, void *arg2, int blocks_modified) 60 { 61 dsl_sync_task_t *dst; 62 63 if (checkfunc == NULL) 64 checkfunc = dsl_null_checkfunc; 65 dst = kmem_zalloc(sizeof (dsl_sync_task_t), KM_SLEEP); 66 dst->dst_checkfunc = checkfunc; 67 dst->dst_syncfunc = syncfunc; 68 dst->dst_arg1 = arg1; 69 dst->dst_arg2 = arg2; 70 list_insert_tail(&dstg->dstg_tasks, dst); 71 72 dstg->dstg_space += blocks_modified << DST_AVG_BLKSHIFT; 73 } 74 75 int 76 dsl_sync_task_group_wait(dsl_sync_task_group_t *dstg) 77 { 78 dmu_tx_t *tx; 79 uint64_t txg; 80 dsl_sync_task_t *dst; 81 82 top: 83 tx = dmu_tx_create_dd(dstg->dstg_pool->dp_mos_dir); 84 VERIFY(0 == dmu_tx_assign(tx, TXG_WAIT)); 85 86 txg = dmu_tx_get_txg(tx); 87 88 /* Do a preliminary error check. */ 89 dstg->dstg_err = 0; 90 rw_enter(&dstg->dstg_pool->dp_config_rwlock, RW_READER); 91 for (dst = list_head(&dstg->dstg_tasks); dst; 92 dst = list_next(&dstg->dstg_tasks, dst)) { 93 #ifdef ZFS_DEBUG 94 /* 95 * Only check half the time, otherwise, the sync-context 96 * check will almost never fail. 97 */ 98 if (spa_get_random(2) == 0) 99 continue; 100 #endif 101 dst->dst_err = 102 dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx); 103 if (dst->dst_err) 104 dstg->dstg_err = dst->dst_err; 105 } 106 rw_exit(&dstg->dstg_pool->dp_config_rwlock); 107 108 if (dstg->dstg_err) { 109 dmu_tx_commit(tx); 110 return (dstg->dstg_err); 111 } 112 113 /* 114 * We don't generally have many sync tasks, so pay the price of 115 * add_tail to get the tasks executed in the right order. 116 */ 117 VERIFY(0 == txg_list_add_tail(&dstg->dstg_pool->dp_sync_tasks, 118 dstg, txg)); 119 120 dmu_tx_commit(tx); 121 122 txg_wait_synced(dstg->dstg_pool, txg); 123 124 if (dstg->dstg_err == EAGAIN) { 125 txg_wait_synced(dstg->dstg_pool, txg + TXG_DEFER_SIZE); 126 goto top; 127 } 128 129 return (dstg->dstg_err); 130 } 131 132 void 133 dsl_sync_task_group_nowait(dsl_sync_task_group_t *dstg, dmu_tx_t *tx) 134 { 135 uint64_t txg; 136 137 dstg->dstg_nowaiter = B_TRUE; 138 txg = dmu_tx_get_txg(tx); 139 /* 140 * We don't generally have many sync tasks, so pay the price of 141 * add_tail to get the tasks executed in the right order. 142 */ 143 VERIFY(0 == txg_list_add_tail(&dstg->dstg_pool->dp_sync_tasks, 144 dstg, txg)); 145 } 146 147 void 148 dsl_sync_task_group_destroy(dsl_sync_task_group_t *dstg) 149 { 150 dsl_sync_task_t *dst; 151 152 while (dst = list_head(&dstg->dstg_tasks)) { 153 list_remove(&dstg->dstg_tasks, dst); 154 kmem_free(dst, sizeof (dsl_sync_task_t)); 155 } 156 kmem_free(dstg, sizeof (dsl_sync_task_group_t)); 157 } 158 159 void 160 dsl_sync_task_group_sync(dsl_sync_task_group_t *dstg, dmu_tx_t *tx) 161 { 162 dsl_sync_task_t *dst; 163 void *tr_cookie; 164 165 ASSERT3U(dstg->dstg_err, ==, 0); 166 167 /* 168 * Check for sufficient space. 169 */ 170 dstg->dstg_err = dsl_dir_tempreserve_space(dstg->dstg_pool->dp_mos_dir, 171 dstg->dstg_space, dstg->dstg_space * 3, 0, 0, &tr_cookie, tx); 172 /* don't bother trying again */ 173 if (dstg->dstg_err == ERESTART) 174 dstg->dstg_err = EAGAIN; 175 if (dstg->dstg_err) 176 return; 177 178 /* 179 * Check for errors by calling checkfuncs. 180 */ 181 rw_enter(&dstg->dstg_pool->dp_config_rwlock, RW_WRITER); 182 for (dst = list_head(&dstg->dstg_tasks); dst; 183 dst = list_next(&dstg->dstg_tasks, dst)) { 184 dst->dst_err = 185 dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx); 186 if (dst->dst_err) 187 dstg->dstg_err = dst->dst_err; 188 } 189 190 if (dstg->dstg_err == 0) { 191 /* 192 * Execute sync tasks. 193 */ 194 for (dst = list_head(&dstg->dstg_tasks); dst; 195 dst = list_next(&dstg->dstg_tasks, dst)) { 196 dst->dst_syncfunc(dst->dst_arg1, dst->dst_arg2, 197 dstg->dstg_cr, tx); 198 } 199 } 200 rw_exit(&dstg->dstg_pool->dp_config_rwlock); 201 202 dsl_dir_tempreserve_clear(tr_cookie, tx); 203 204 if (dstg->dstg_nowaiter) 205 dsl_sync_task_group_destroy(dstg); 206 } 207 208 int 209 dsl_sync_task_do(dsl_pool_t *dp, 210 dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc, 211 void *arg1, void *arg2, int blocks_modified) 212 { 213 dsl_sync_task_group_t *dstg; 214 int err; 215 216 dstg = dsl_sync_task_group_create(dp); 217 dsl_sync_task_create(dstg, checkfunc, syncfunc, 218 arg1, arg2, blocks_modified); 219 err = dsl_sync_task_group_wait(dstg); 220 dsl_sync_task_group_destroy(dstg); 221 return (err); 222 } 223 224 void 225 dsl_sync_task_do_nowait(dsl_pool_t *dp, 226 dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc, 227 void *arg1, void *arg2, int blocks_modified, dmu_tx_t *tx) 228 { 229 dsl_sync_task_group_t *dstg; 230 231 dstg = dsl_sync_task_group_create(dp); 232 dsl_sync_task_create(dstg, checkfunc, syncfunc, 233 arg1, arg2, blocks_modified); 234 dsl_sync_task_group_nowait(dstg, tx); 235 } 236