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