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  * Copyright (c) 2012, 2016 by Delphix. All rights reserved.
27  */
28 
29 #ifndef	_SYS_DMU_TX_H
30 #define	_SYS_DMU_TX_H
31 
32 #include <sys/inttypes.h>
33 #include <sys/dmu.h>
34 #include <sys/txg.h>
35 #include <sys/zfs_refcount.h>
36 
37 #ifdef	__cplusplus
38 extern "C" {
39 #endif
40 
41 struct dmu_buf_impl;
42 struct dmu_tx_hold;
43 struct dnode_link;
44 struct dsl_pool;
45 struct dnode;
46 struct dsl_dir;
47 
48 struct dmu_tx {
49 	/*
50 	 * No synchronization is needed because a tx can only be handled
51 	 * by one thread.
52 	 */
53 	list_t tx_holds; /* list of dmu_tx_hold_t */
54 	objset_t *tx_objset;
55 	struct dsl_dir *tx_dir;
56 	struct dsl_pool *tx_pool;
57 	uint64_t tx_txg;
58 	uint64_t tx_lastsnap_txg;
59 	uint64_t tx_lasttried_txg;
60 	txg_handle_t tx_txgh;
61 	void *tx_tempreserve_cookie;
62 	struct dmu_tx_hold *tx_needassign_txh;
63 
64 	/* list of dmu_tx_callback_t on this dmu_tx */
65 	list_t tx_callbacks;
66 
67 	/* placeholder for syncing context, doesn't need specific holds */
68 	boolean_t tx_anyobj;
69 
70 	/* transaction is marked as being a "net free" of space */
71 	boolean_t tx_netfree;
72 
73 	/* time this transaction was created */
74 	hrtime_t tx_start;
75 
76 	/* need to wait for sufficient dirty space */
77 	boolean_t tx_wait_dirty;
78 
79 	/* has this transaction already been delayed? */
80 	boolean_t tx_dirty_delayed;
81 
82 	int tx_err;
83 };
84 
85 enum dmu_tx_hold_type {
86 	THT_NEWOBJECT,
87 	THT_WRITE,
88 	THT_BONUS,
89 	THT_FREE,
90 	THT_ZAP,
91 	THT_SPACE,
92 	THT_SPILL,
93 	THT_NUMTYPES
94 };
95 
96 typedef struct dmu_tx_hold {
97 	dmu_tx_t *txh_tx;
98 	list_node_t txh_node;
99 	struct dnode *txh_dnode;
100 	zfs_refcount_t txh_space_towrite;
101 	zfs_refcount_t txh_memory_tohold;
102 	enum dmu_tx_hold_type txh_type;
103 	uint64_t txh_arg1;
104 	uint64_t txh_arg2;
105 } dmu_tx_hold_t;
106 
107 typedef struct dmu_tx_callback {
108 	list_node_t		dcb_node;    /* linked to tx_callbacks list */
109 	dmu_tx_callback_func_t	*dcb_func;   /* caller function pointer */
110 	void			*dcb_data;   /* caller private data */
111 } dmu_tx_callback_t;
112 
113 /*
114  * Used for dmu tx kstat.
115  */
116 typedef struct dmu_tx_stats {
117 	kstat_named_t dmu_tx_assigned;
118 	kstat_named_t dmu_tx_delay;
119 	kstat_named_t dmu_tx_error;
120 	kstat_named_t dmu_tx_suspended;
121 	kstat_named_t dmu_tx_group;
122 	kstat_named_t dmu_tx_memory_reserve;
123 	kstat_named_t dmu_tx_memory_reclaim;
124 	kstat_named_t dmu_tx_dirty_throttle;
125 	kstat_named_t dmu_tx_dirty_delay;
126 	kstat_named_t dmu_tx_dirty_over_max;
127 	kstat_named_t dmu_tx_dirty_frees_delay;
128 	kstat_named_t dmu_tx_quota;
129 } dmu_tx_stats_t;
130 
131 extern dmu_tx_stats_t dmu_tx_stats;
132 
133 #define	DMU_TX_STAT_INCR(stat, val) \
134     atomic_add_64(&dmu_tx_stats.stat.value.ui64, (val));
135 #define	DMU_TX_STAT_BUMP(stat) \
136     DMU_TX_STAT_INCR(stat, 1);
137 
138 /*
139  * These routines are defined in dmu.h, and are called by the user.
140  */
141 dmu_tx_t *dmu_tx_create(objset_t *dd);
142 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how);
143 void dmu_tx_commit(dmu_tx_t *tx);
144 void dmu_tx_abort(dmu_tx_t *tx);
145 uint64_t dmu_tx_get_txg(dmu_tx_t *tx);
146 struct dsl_pool *dmu_tx_pool(dmu_tx_t *tx);
147 void dmu_tx_wait(dmu_tx_t *tx);
148 
149 /*
150  * These routines are defined in dmu_spa.h, and are called by the SPA.
151  */
152 extern dmu_tx_t *dmu_tx_create_assigned(struct dsl_pool *dp, uint64_t txg);
153 
154 /*
155  * These routines are only called by the DMU.
156  */
157 dmu_tx_t *dmu_tx_create_dd(dsl_dir_t *dd);
158 int dmu_tx_is_syncing(dmu_tx_t *tx);
159 int dmu_tx_private_ok(dmu_tx_t *tx);
160 void dmu_tx_add_new_object(dmu_tx_t *tx, dnode_t *dn);
161 void dmu_tx_dirty_buf(dmu_tx_t *tx, struct dmu_buf_impl *db);
162 void dmu_tx_hold_space(dmu_tx_t *tx, uint64_t space);
163 
164 #ifdef ZFS_DEBUG
165 #define	DMU_TX_DIRTY_BUF(tx, db)	dmu_tx_dirty_buf(tx, db)
166 #else
167 #define	DMU_TX_DIRTY_BUF(tx, db)
168 #endif
169 
170 void dmu_tx_init(void);
171 void dmu_tx_fini(void);
172 
173 #ifdef	__cplusplus
174 }
175 #endif
176 
177 #endif	/* _SYS_DMU_TX_H */
178