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/metaslab.h> 32 #include <sys/cred.h> 33 34 #define DST_AVG_BLKSHIFT 14 35 36 /* ARGSUSED */ 37 static int 38 dsl_null_checkfunc(void *arg1, void *arg2, dmu_tx_t *tx) 39 { 40 return (0); 41 } 42 43 dsl_sync_task_group_t * 44 dsl_sync_task_group_create(dsl_pool_t *dp) 45 { 46 dsl_sync_task_group_t *dstg; 47 48 dstg = kmem_zalloc(sizeof (dsl_sync_task_group_t), KM_SLEEP); 49 list_create(&dstg->dstg_tasks, sizeof (dsl_sync_task_t), 50 offsetof(dsl_sync_task_t, dst_node)); 51 dstg->dstg_pool = dp; 52 dstg->dstg_cr = CRED(); 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 list_insert_tail(&dstg->dstg_tasks, dst); 72 73 dstg->dstg_space += blocks_modified << DST_AVG_BLKSHIFT; 74 } 75 76 int 77 dsl_sync_task_group_wait(dsl_sync_task_group_t *dstg) 78 { 79 dmu_tx_t *tx; 80 uint64_t txg; 81 dsl_sync_task_t *dst; 82 83 top: 84 tx = dmu_tx_create_dd(dstg->dstg_pool->dp_mos_dir); 85 VERIFY(0 == dmu_tx_assign(tx, TXG_WAIT)); 86 87 txg = dmu_tx_get_txg(tx); 88 89 /* Do a preliminary error check. */ 90 dstg->dstg_err = 0; 91 rw_enter(&dstg->dstg_pool->dp_config_rwlock, RW_READER); 92 for (dst = list_head(&dstg->dstg_tasks); dst; 93 dst = list_next(&dstg->dstg_tasks, dst)) { 94 #ifdef ZFS_DEBUG 95 /* 96 * Only check half the time, otherwise, the sync-context 97 * check will almost never fail. 98 */ 99 if (spa_get_random(2) == 0) 100 continue; 101 #endif 102 dst->dst_err = 103 dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx); 104 if (dst->dst_err) 105 dstg->dstg_err = dst->dst_err; 106 } 107 rw_exit(&dstg->dstg_pool->dp_config_rwlock); 108 109 if (dstg->dstg_err) { 110 dmu_tx_commit(tx); 111 return (dstg->dstg_err); 112 } 113 114 /* 115 * We don't generally have many sync tasks, so pay the price of 116 * add_tail to get the tasks executed in the right order. 117 */ 118 VERIFY(0 == txg_list_add_tail(&dstg->dstg_pool->dp_sync_tasks, 119 dstg, txg)); 120 121 dmu_tx_commit(tx); 122 123 txg_wait_synced(dstg->dstg_pool, txg); 124 125 if (dstg->dstg_err == EAGAIN) { 126 txg_wait_synced(dstg->dstg_pool, txg + TXG_DEFER_SIZE); 127 goto top; 128 } 129 130 return (dstg->dstg_err); 131 } 132 133 void 134 dsl_sync_task_group_nowait(dsl_sync_task_group_t *dstg, dmu_tx_t *tx) 135 { 136 uint64_t txg; 137 138 dstg->dstg_nowaiter = B_TRUE; 139 dstg->dstg_cr = NULL; /* it won't be valid by the time we sync */ 140 txg = dmu_tx_get_txg(tx); 141 /* 142 * We don't generally have many sync tasks, so pay the price of 143 * add_tail to get the tasks executed in the right order. 144 */ 145 VERIFY(0 == txg_list_add_tail(&dstg->dstg_pool->dp_sync_tasks, 146 dstg, txg)); 147 } 148 149 void 150 dsl_sync_task_group_destroy(dsl_sync_task_group_t *dstg) 151 { 152 dsl_sync_task_t *dst; 153 154 while (dst = list_head(&dstg->dstg_tasks)) { 155 list_remove(&dstg->dstg_tasks, dst); 156 kmem_free(dst, sizeof (dsl_sync_task_t)); 157 } 158 kmem_free(dstg, sizeof (dsl_sync_task_group_t)); 159 } 160 161 void 162 dsl_sync_task_group_sync(dsl_sync_task_group_t *dstg, dmu_tx_t *tx) 163 { 164 dsl_sync_task_t *dst; 165 dsl_pool_t *dp = dstg->dstg_pool; 166 uint64_t quota, used; 167 168 ASSERT3U(dstg->dstg_err, ==, 0); 169 170 /* 171 * Check for sufficient space. We just check against what's 172 * on-disk; we don't want any in-flight accounting to get in our 173 * way, because open context may have already used up various 174 * in-core limits (arc_tempreserve, dsl_pool_tempreserve). 175 */ 176 quota = dsl_pool_adjustedsize(dp, B_FALSE) - 177 metaslab_class_get_deferred(spa_normal_class(dp->dp_spa)); 178 used = dp->dp_root_dir->dd_phys->dd_used_bytes; 179 /* MOS space is triple-dittoed, so we multiply by 3. */ 180 if (dstg->dstg_space > 0 && used + dstg->dstg_space * 3 > quota) { 181 dstg->dstg_err = ENOSPC; 182 return; 183 } 184 185 /* 186 * Check for errors by calling checkfuncs. 187 */ 188 rw_enter(&dp->dp_config_rwlock, RW_WRITER); 189 for (dst = list_head(&dstg->dstg_tasks); dst; 190 dst = list_next(&dstg->dstg_tasks, dst)) { 191 dst->dst_err = 192 dst->dst_checkfunc(dst->dst_arg1, dst->dst_arg2, tx); 193 if (dst->dst_err) 194 dstg->dstg_err = dst->dst_err; 195 } 196 197 if (dstg->dstg_err == 0) { 198 /* 199 * Execute sync tasks. 200 */ 201 for (dst = list_head(&dstg->dstg_tasks); dst; 202 dst = list_next(&dstg->dstg_tasks, dst)) { 203 dst->dst_syncfunc(dst->dst_arg1, dst->dst_arg2, 204 dstg->dstg_cr, tx); 205 } 206 } 207 rw_exit(&dp->dp_config_rwlock); 208 209 if (dstg->dstg_nowaiter) 210 dsl_sync_task_group_destroy(dstg); 211 } 212 213 int 214 dsl_sync_task_do(dsl_pool_t *dp, 215 dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc, 216 void *arg1, void *arg2, int blocks_modified) 217 { 218 dsl_sync_task_group_t *dstg; 219 int err; 220 221 dstg = dsl_sync_task_group_create(dp); 222 dsl_sync_task_create(dstg, checkfunc, syncfunc, 223 arg1, arg2, blocks_modified); 224 err = dsl_sync_task_group_wait(dstg); 225 dsl_sync_task_group_destroy(dstg); 226 return (err); 227 } 228 229 void 230 dsl_sync_task_do_nowait(dsl_pool_t *dp, 231 dsl_checkfunc_t *checkfunc, dsl_syncfunc_t *syncfunc, 232 void *arg1, void *arg2, int blocks_modified, dmu_tx_t *tx) 233 { 234 dsl_sync_task_group_t *dstg; 235 236 dstg = dsl_sync_task_group_create(dp); 237 dsl_sync_task_create(dstg, checkfunc, syncfunc, 238 arg1, arg2, blocks_modified); 239 dsl_sync_task_group_nowait(dstg, tx); 240 } 241