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 * Copyright (c) 2012, 2017 by Delphix. All rights reserved. 24 * Copyright (c) 2014 Integros [integros.com] 25 */ 26 27 /* Portions Copyright 2010 Robert Milkowski */ 28 29 #ifndef _SYS_ZIL_IMPL_H 30 #define _SYS_ZIL_IMPL_H 31 32 #include <sys/zil.h> 33 #include <sys/dmu_objset.h> 34 35 #ifdef __cplusplus 36 extern "C" { 37 #endif 38 39 /* 40 * Possbile states for a given lwb structure. An lwb will start out in 41 * the "closed" state, and then transition to the "opened" state via a 42 * call to zil_lwb_write_open(). After the lwb is "open", it can 43 * transition into the "issued" state via zil_lwb_write_issue(). After 44 * the lwb's zio completes, and the vdev's are flushed, the lwb will 45 * transition into the "done" state via zil_lwb_write_done(), and the 46 * structure eventually freed. 47 */ 48 typedef enum { 49 LWB_STATE_CLOSED, 50 LWB_STATE_OPENED, 51 LWB_STATE_ISSUED, 52 LWB_STATE_DONE, 53 LWB_NUM_STATES 54 } lwb_state_t; 55 56 /* 57 * Log write block (lwb) 58 * 59 * Prior to an lwb being issued to disk via zil_lwb_write_issue(), it 60 * will be protected by the zilog's "zl_issuer_lock". Basically, prior 61 * to it being issued, it will only be accessed by the thread that's 62 * holding the "zl_issuer_lock". After the lwb is issued, the zilog's 63 * "zl_lock" is used to protect the lwb against concurrent access. 64 */ 65 typedef struct lwb { 66 zilog_t *lwb_zilog; /* back pointer to log struct */ 67 blkptr_t lwb_blk; /* on disk address of this log blk */ 68 boolean_t lwb_slog; /* lwb_blk is on SLOG device */ 69 int lwb_nused; /* # used bytes in buffer */ 70 int lwb_sz; /* size of block and buffer */ 71 lwb_state_t lwb_state; /* the state of this lwb */ 72 char *lwb_buf; /* log write buffer */ 73 zio_t *lwb_write_zio; /* zio for the lwb buffer */ 74 zio_t *lwb_root_zio; /* root zio for lwb write and flushes */ 75 dmu_tx_t *lwb_tx; /* tx for log block allocation */ 76 uint64_t lwb_max_txg; /* highest txg in this lwb */ 77 list_node_t lwb_node; /* zilog->zl_lwb_list linkage */ 78 list_t lwb_waiters; /* list of zil_commit_waiter's */ 79 avl_tree_t lwb_vdev_tree; /* vdevs to flush after lwb write */ 80 kmutex_t lwb_vdev_lock; /* protects lwb_vdev_tree */ 81 hrtime_t lwb_issued_timestamp; /* when was the lwb issued? */ 82 } lwb_t; 83 84 /* 85 * ZIL commit waiter. 86 * 87 * This structure is allocated each time zil_commit() is called, and is 88 * used by zil_commit() to communicate with other parts of the ZIL, such 89 * that zil_commit() can know when it safe for it return. For more 90 * details, see the comment above zil_commit(). 91 * 92 * The "zcw_lock" field is used to protect the commit waiter against 93 * concurrent access. This lock is often acquired while already holding 94 * the zilog's "zl_issuer_lock" or "zl_lock"; see the functions 95 * zil_process_commit_list() and zil_lwb_flush_vdevs_done() as examples 96 * of this. Thus, one must be careful not to acquire the 97 * "zl_issuer_lock" or "zl_lock" when already holding the "zcw_lock"; 98 * e.g. see the zil_commit_waiter_timeout() function. 99 */ 100 typedef struct zil_commit_waiter { 101 kcondvar_t zcw_cv; /* signalled when "done" */ 102 kmutex_t zcw_lock; /* protects fields of this struct */ 103 list_node_t zcw_node; /* linkage in lwb_t:lwb_waiter list */ 104 lwb_t *zcw_lwb; /* back pointer to lwb when linked */ 105 boolean_t zcw_done; /* B_TRUE when "done", else B_FALSE */ 106 int zcw_zio_error; /* contains the zio io_error value */ 107 } zil_commit_waiter_t; 108 109 /* 110 * Intent log transaction lists 111 */ 112 typedef struct itxs { 113 list_t i_sync_list; /* list of synchronous itxs */ 114 avl_tree_t i_async_tree; /* tree of foids for async itxs */ 115 } itxs_t; 116 117 typedef struct itxg { 118 kmutex_t itxg_lock; /* lock for this structure */ 119 uint64_t itxg_txg; /* txg for this chain */ 120 itxs_t *itxg_itxs; /* sync and async itxs */ 121 } itxg_t; 122 123 /* for async nodes we build up an AVL tree of lists of async itxs per file */ 124 typedef struct itx_async_node { 125 uint64_t ia_foid; /* file object id */ 126 list_t ia_list; /* list of async itxs for this foid */ 127 avl_node_t ia_node; /* AVL tree linkage */ 128 } itx_async_node_t; 129 130 /* 131 * Vdev flushing: during a zil_commit(), we build up an AVL tree of the vdevs 132 * we've touched so we know which ones need a write cache flush at the end. 133 */ 134 typedef struct zil_vdev_node { 135 uint64_t zv_vdev; /* vdev to be flushed */ 136 avl_node_t zv_node; /* AVL tree linkage */ 137 } zil_vdev_node_t; 138 139 #define ZIL_PREV_BLKS 16 140 141 /* 142 * Stable storage intent log management structure. One per dataset. 143 */ 144 struct zilog { 145 kmutex_t zl_lock; /* protects most zilog_t fields */ 146 struct dsl_pool *zl_dmu_pool; /* DSL pool */ 147 spa_t *zl_spa; /* handle for read/write log */ 148 const zil_header_t *zl_header; /* log header buffer */ 149 objset_t *zl_os; /* object set we're logging */ 150 zil_get_data_t *zl_get_data; /* callback to get object content */ 151 lwb_t *zl_last_lwb_opened; /* most recent lwb opened */ 152 hrtime_t zl_last_lwb_latency; /* zio latency of last lwb done */ 153 uint64_t zl_lr_seq; /* on-disk log record sequence number */ 154 uint64_t zl_commit_lr_seq; /* last committed on-disk lr seq */ 155 uint64_t zl_destroy_txg; /* txg of last zil_destroy() */ 156 uint64_t zl_replayed_seq[TXG_SIZE]; /* last replayed rec seq */ 157 uint64_t zl_replaying_seq; /* current replay seq number */ 158 uint32_t zl_suspend; /* log suspend count */ 159 kcondvar_t zl_cv_suspend; /* log suspend completion */ 160 uint8_t zl_suspending; /* log is currently suspending */ 161 uint8_t zl_keep_first; /* keep first log block in destroy */ 162 uint8_t zl_replay; /* replaying records while set */ 163 uint8_t zl_stop_sync; /* for debugging */ 164 kmutex_t zl_issuer_lock; /* single writer, per ZIL, at a time */ 165 uint8_t zl_logbias; /* latency or throughput */ 166 uint8_t zl_sync; /* synchronous or asynchronous */ 167 int zl_parse_error; /* last zil_parse() error */ 168 uint64_t zl_parse_blk_seq; /* highest blk seq on last parse */ 169 uint64_t zl_parse_lr_seq; /* highest lr seq on last parse */ 170 uint64_t zl_parse_blk_count; /* number of blocks parsed */ 171 uint64_t zl_parse_lr_count; /* number of log records parsed */ 172 itxg_t zl_itxg[TXG_SIZE]; /* intent log txg chains */ 173 list_t zl_itx_commit_list; /* itx list to be committed */ 174 uint64_t zl_cur_used; /* current commit log size used */ 175 list_t zl_lwb_list; /* in-flight log write list */ 176 avl_tree_t zl_bp_tree; /* track bps during log parse */ 177 clock_t zl_replay_time; /* lbolt of when replay started */ 178 uint64_t zl_replay_blks; /* number of log blocks replayed */ 179 zil_header_t zl_old_header; /* debugging aid */ 180 uint_t zl_prev_blks[ZIL_PREV_BLKS]; /* size - sector rounded */ 181 uint_t zl_prev_rotor; /* rotor for zl_prev[] */ 182 txg_node_t zl_dirty_link; /* protected by dp_dirty_zilogs list */ 183 uint64_t zl_dirty_max_txg; /* highest txg used to dirty zilog */ 184 }; 185 186 typedef struct zil_bp_node { 187 dva_t zn_dva; 188 avl_node_t zn_node; 189 } zil_bp_node_t; 190 191 /* 192 * Maximum amount of write data that can be put into single log block. 193 */ 194 #define ZIL_MAX_LOG_DATA (SPA_OLD_MAXBLOCKSIZE - sizeof (zil_chain_t) - \ 195 sizeof (lr_write_t)) 196 197 /* 198 * Maximum amount of log space we agree to waste to reduce number of 199 * WR_NEED_COPY chunks to reduce zl_get_data() overhead (~12%). 200 */ 201 #define ZIL_MAX_WASTE_SPACE (ZIL_MAX_LOG_DATA / 8) 202 203 /* 204 * Maximum amount of write data for WR_COPIED. Fall back to WR_NEED_COPY 205 * as more space efficient if we can't fit at least two log records into 206 * maximum sized log block. 207 */ 208 #define ZIL_MAX_COPIED_DATA ((SPA_OLD_MAXBLOCKSIZE - \ 209 sizeof (zil_chain_t)) / 2 - sizeof (lr_write_t)) 210 211 #ifdef __cplusplus 212 } 213 #endif 214 215 #endif /* _SYS_ZIL_IMPL_H */ 216