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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 */ 24 25 #include <sys/dmu.h> 26 #include <sys/dmu_tx.h> 27 #include <sys/dsl_pool.h> 28 #include <sys/dsl_dir.h> 29 #include <sys/dsl_synctask.h> 30 #include <sys/metaslab.h> 31 32 #define DST_AVG_BLKSHIFT 14 33 34 /* ARGSUSED */ 35 static int 36 dsl_null_checkfunc(void *arg1, void *arg2, dmu_tx_t *tx) 37 { 38 return (0); 39 } 40 41 dsl_sync_task_group_t * 42 dsl_sync_task_group_create(dsl_pool_t *dp) 43 { 44 dsl_sync_task_group_t *dstg; 45 46 dstg = kmem_zalloc(sizeof (dsl_sync_task_group_t), KM_SLEEP); 47 list_create(&dstg->dstg_tasks, sizeof (dsl_sync_task_t), 48 offsetof(dsl_sync_task_t, dst_node)); 49 dstg->dstg_pool = dp; 50 51 return (dstg); 52 } 53 54 void 55 dsl_sync_task_create(dsl_sync_task_group_t *dstg, 56 dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc, 57 void *arg1, void *arg2, int blocks_modified) 58 { 59 dsl_sync_task_t *dst; 60 61 if (checkfunc == NULL) 62 checkfunc = dsl_null_checkfunc; 63 dst = kmem_zalloc(sizeof (dsl_sync_task_t), KM_SLEEP); 64 dst->dst_checkfunc = checkfunc; 65 dst->dst_syncfunc = syncfunc; 66 dst->dst_arg1 = arg1; 67 dst->dst_arg2 = arg2; 68 list_insert_tail(&dstg->dstg_tasks, dst); 69 70 dstg->dstg_space += blocks_modified << DST_AVG_BLKSHIFT; 71 } 72 73 int 74 dsl_sync_task_group_wait(dsl_sync_task_group_t *dstg) 75 { 76 dmu_tx_t *tx; 77 uint64_t txg; 78 dsl_sync_task_t *dst; 79 80 top: 81 tx = dmu_tx_create_dd(dstg->dstg_pool->dp_mos_dir); 82 VERIFY(0 == dmu_tx_assign(tx, TXG_WAIT)); 83 84 txg = dmu_tx_get_txg(tx); 85 86 /* Do a preliminary error check. */ 87 dstg->dstg_err = 0; 88 rw_enter(&dstg->dstg_pool->dp_config_rwlock, RW_READER); 89 for (dst = list_head(&dstg->dstg_tasks); dst; 90 dst = list_next(&dstg->dstg_tasks, dst)) { 91 #ifdef ZFS_DEBUG 92 /* 93 * Only check half the time, otherwise, the sync-context 94 * check will almost never fail. 95 */ 96 if (spa_get_random(2) == 0) 97 continue; 98 #endif 99 dst->dst_err = 100 dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx); 101 if (dst->dst_err) 102 dstg->dstg_err = dst->dst_err; 103 } 104 rw_exit(&dstg->dstg_pool->dp_config_rwlock); 105 106 if (dstg->dstg_err) { 107 dmu_tx_commit(tx); 108 return (dstg->dstg_err); 109 } 110 111 /* 112 * We don't generally have many sync tasks, so pay the price of 113 * add_tail to get the tasks executed in the right order. 114 */ 115 VERIFY(0 == txg_list_add_tail(&dstg->dstg_pool->dp_sync_tasks, 116 dstg, txg)); 117 118 dmu_tx_commit(tx); 119 120 txg_wait_synced(dstg->dstg_pool, txg); 121 122 if (dstg->dstg_err == EAGAIN) { 123 txg_wait_synced(dstg->dstg_pool, txg + TXG_DEFER_SIZE); 124 goto top; 125 } 126 127 return (dstg->dstg_err); 128 } 129 130 void 131 dsl_sync_task_group_nowait(dsl_sync_task_group_t *dstg, dmu_tx_t *tx) 132 { 133 uint64_t txg; 134 135 dstg->dstg_nowaiter = B_TRUE; 136 txg = dmu_tx_get_txg(tx); 137 /* 138 * We don't generally have many sync tasks, so pay the price of 139 * add_tail to get the tasks executed in the right order. 140 */ 141 VERIFY(0 == txg_list_add_tail(&dstg->dstg_pool->dp_sync_tasks, 142 dstg, txg)); 143 } 144 145 void 146 dsl_sync_task_group_destroy(dsl_sync_task_group_t *dstg) 147 { 148 dsl_sync_task_t *dst; 149 150 while (dst = list_head(&dstg->dstg_tasks)) { 151 list_remove(&dstg->dstg_tasks, dst); 152 kmem_free(dst, sizeof (dsl_sync_task_t)); 153 } 154 kmem_free(dstg, sizeof (dsl_sync_task_group_t)); 155 } 156 157 void 158 dsl_sync_task_group_sync(dsl_sync_task_group_t *dstg, dmu_tx_t *tx) 159 { 160 dsl_sync_task_t *dst; 161 dsl_pool_t *dp = dstg->dstg_pool; 162 uint64_t quota, used; 163 164 ASSERT3U(dstg->dstg_err, ==, 0); 165 166 /* 167 * Check for sufficient space. We just check against what's 168 * on-disk; we don't want any in-flight accounting to get in our 169 * way, because open context may have already used up various 170 * in-core limits (arc_tempreserve, dsl_pool_tempreserve). 171 */ 172 quota = dsl_pool_adjustedsize(dp, B_FALSE) - 173 metaslab_class_get_deferred(spa_normal_class(dp->dp_spa)); 174 used = dp->dp_root_dir->dd_phys->dd_used_bytes; 175 /* MOS space is triple-dittoed, so we multiply by 3. */ 176 if (dstg->dstg_space > 0 && used + dstg->dstg_space * 3 > quota) { 177 dstg->dstg_err = ENOSPC; 178 return; 179 } 180 181 /* 182 * Check for errors by calling checkfuncs. 183 */ 184 rw_enter(&dp->dp_config_rwlock, RW_WRITER); 185 for (dst = list_head(&dstg->dstg_tasks); dst; 186 dst = list_next(&dstg->dstg_tasks, dst)) { 187 dst->dst_err = 188 dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx); 189 if (dst->dst_err) 190 dstg->dstg_err = dst->dst_err; 191 } 192 193 if (dstg->dstg_err == 0) { 194 /* 195 * Execute sync tasks. 196 */ 197 for (dst = list_head(&dstg->dstg_tasks); dst; 198 dst = list_next(&dstg->dstg_tasks, dst)) { 199 dst->dst_syncfunc(dst->dst_arg1, dst->dst_arg2, tx); 200 } 201 } 202 rw_exit(&dp->dp_config_rwlock); 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