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 https://opensource.org/licenses/CDDL-1.0. 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 */ 25 26 #ifndef _SYS_DSL_SYNCTASK_H 27 #define _SYS_DSL_SYNCTASK_H 28 29 #include <sys/txg.h> 30 #include <sys/zfs_context.h> 31 32 #ifdef __cplusplus 33 extern "C" { 34 #endif 35 36 struct dsl_pool; 37 38 typedef int (dsl_checkfunc_t)(void *, dmu_tx_t *); 39 typedef void (dsl_syncfunc_t)(void *, dmu_tx_t *); 40 typedef void (dsl_sigfunc_t)(void *, dmu_tx_t *); 41 42 typedef enum zfs_space_check { 43 /* 44 * Normal space check: if there is less than 3.2% free space (bounded 45 * by spa_max_slop), the operation will fail. Operations which are 46 * logically creating things should use this (e.g. "zfs create", "zfs 47 * snapshot"). User writes (via the ZPL / ZVOL) also fail at this 48 * point. 49 */ 50 ZFS_SPACE_CHECK_NORMAL, 51 52 /* 53 * Space check allows use of half the slop space. If there 54 * is less than 1.6% free space, the operation will fail. Most 55 * operations should use this (e.g. "zfs set", "zfs rename"), 56 * because we want them to succeed even after user writes are failing, 57 * so that they can be used as part of the space recovery process. 58 */ 59 ZFS_SPACE_CHECK_RESERVED, 60 61 /* 62 * Space check allows use of three quarters of the slop space. 63 * If there is less than 0.8% free space, the operation will 64 * fail. 65 */ 66 ZFS_SPACE_CHECK_EXTRA_RESERVED, 67 68 /* 69 * In all cases "zfs destroy" is expected to result in an net 70 * reduction of space, except one. When the pool has a 71 * checkpoint, space freed by "zfs destroy" will not actually 72 * free anything internally. Thus, it starts failing after 73 * three quarters of the slop space is exceeded. 74 */ 75 ZFS_SPACE_CHECK_DESTROY = ZFS_SPACE_CHECK_EXTRA_RESERVED, 76 77 /* 78 * A channel program can run a "zfs destroy" as part of its 79 * script and therefore has the same space_check policy when 80 * being evaluated. 81 */ 82 ZFS_SPACE_CHECK_ZCP_EVAL = ZFS_SPACE_CHECK_DESTROY, 83 84 /* 85 * No space check is performed. This level of space check should 86 * be used cautiously as operations that use it can even run when 87 * 0.8% capacity is left for use. In this scenario, if there is a 88 * checkpoint, async destroys are suspended and any kind of freeing 89 * can potentially add space instead of freeing it. 90 * 91 * See also the comments above spa_slop_shift. 92 */ 93 ZFS_SPACE_CHECK_NONE, 94 95 ZFS_SPACE_CHECK_DISCARD_CHECKPOINT = ZFS_SPACE_CHECK_NONE, 96 97 } zfs_space_check_t; 98 99 typedef struct dsl_sync_task { 100 txg_node_t dst_node; 101 struct dsl_pool *dst_pool; 102 uint64_t dst_txg; 103 int dst_space; 104 zfs_space_check_t dst_space_check; 105 dsl_checkfunc_t *dst_checkfunc; 106 dsl_syncfunc_t *dst_syncfunc; 107 void *dst_arg; 108 int dst_error; 109 boolean_t dst_nowaiter; 110 } dsl_sync_task_t; 111 112 void dsl_sync_task_sync(dsl_sync_task_t *, dmu_tx_t *); 113 int dsl_sync_task(const char *, dsl_checkfunc_t *, 114 dsl_syncfunc_t *, void *, int, zfs_space_check_t); 115 void dsl_sync_task_nowait(struct dsl_pool *, dsl_syncfunc_t *, 116 void *, dmu_tx_t *); 117 int dsl_early_sync_task(const char *, dsl_checkfunc_t *, 118 dsl_syncfunc_t *, void *, int, zfs_space_check_t); 119 void dsl_early_sync_task_nowait(struct dsl_pool *, dsl_syncfunc_t *, 120 void *, dmu_tx_t *); 121 int dsl_sync_task_sig(const char *, dsl_checkfunc_t *, dsl_syncfunc_t *, 122 dsl_sigfunc_t *, void *, int, zfs_space_check_t); 123 124 #ifdef __cplusplus 125 } 126 #endif 127 128 #endif /* _SYS_DSL_SYNCTASK_H */ 129