xref: /freebsd/sys/contrib/openzfs/include/sys/abd.h (revision 7a7741af18d6c8a804cc643cb7ecda9d730c6aa6)
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) 2014 by Chunwei Chen. All rights reserved.
23  * Copyright (c) 2016, 2019 by Delphix. All rights reserved.
24  */
25 
26 #ifndef _ABD_H
27 #define	_ABD_H
28 
29 #include <sys/isa_defs.h>
30 #include <sys/debug.h>
31 #include <sys/zfs_refcount.h>
32 #include <sys/uio.h>
33 #include <sys/abd_os.h>
34 
35 #ifdef __cplusplus
36 extern "C" {
37 #endif
38 
39 typedef enum abd_flags {
40 	ABD_FLAG_LINEAR		= 1 << 0, /* is buffer linear (or scattered)? */
41 	ABD_FLAG_OWNER		= 1 << 1, /* does it own its data buffers? */
42 	ABD_FLAG_META		= 1 << 2, /* does this represent FS metadata? */
43 	ABD_FLAG_MULTI_ZONE  	= 1 << 3, /* pages split over memory zones */
44 	ABD_FLAG_MULTI_CHUNK 	= 1 << 4, /* pages split over multiple chunks */
45 	ABD_FLAG_LINEAR_PAGE 	= 1 << 5, /* linear but allocd from page */
46 	ABD_FLAG_GANG		= 1 << 6, /* mult ABDs chained together */
47 	ABD_FLAG_GANG_FREE	= 1 << 7, /* gang ABD is responsible for mem */
48 	ABD_FLAG_ALLOCD		= 1 << 8, /* we allocated the abd_t */
49 	ABD_FLAG_FROM_PAGES	= 1 << 9, /* does not own pages */
50 } abd_flags_t;
51 
52 typedef struct abd {
53 	abd_flags_t	abd_flags;
54 	uint_t		abd_size;	/* excludes scattered abd_offset */
55 	list_node_t	abd_gang_link;
56 #ifdef ZFS_DEBUG
57 	struct abd	*abd_parent;
58 	zfs_refcount_t	abd_children;
59 #endif
60 	kmutex_t	abd_mtx;
61 	union {
62 		struct abd_scatter	abd_scatter;
63 		struct abd_linear	abd_linear;
64 		struct abd_gang {
65 			list_t abd_gang_chain;
66 		} abd_gang;
67 	} abd_u;
68 } abd_t;
69 
70 typedef int abd_iter_func_t(void *buf, size_t len, void *priv);
71 typedef int abd_iter_func2_t(void *bufa, void *bufb, size_t len, void *priv);
72 
73 extern int zfs_abd_scatter_enabled;
74 
75 /*
76  * Allocations and deallocations
77  */
78 
79 __attribute__((malloc))
80 abd_t *abd_alloc(size_t, boolean_t);
81 __attribute__((malloc))
82 abd_t *abd_alloc_linear(size_t, boolean_t);
83 __attribute__((malloc))
84 abd_t *abd_alloc_gang(void);
85 __attribute__((malloc))
86 abd_t *abd_alloc_for_io(size_t, boolean_t);
87 __attribute__((malloc))
88 abd_t *abd_alloc_sametype(abd_t *, size_t);
89 boolean_t abd_size_alloc_linear(size_t);
90 void abd_gang_add(abd_t *, abd_t *, boolean_t);
91 void abd_free(abd_t *);
92 abd_t *abd_get_offset(abd_t *, size_t);
93 abd_t *abd_get_offset_size(abd_t *, size_t, size_t);
94 abd_t *abd_get_offset_struct(abd_t *, abd_t *, size_t, size_t);
95 abd_t *abd_get_zeros(size_t);
96 abd_t *abd_get_from_buf(void *, size_t);
97 abd_t *abd_get_from_buf_struct(abd_t *, void *, size_t);
98 void abd_cache_reap_now(void);
99 
100 /*
101  * Conversion to and from a normal buffer
102  */
103 
104 void *abd_to_buf(abd_t *);
105 void *abd_borrow_buf(abd_t *, size_t);
106 void *abd_borrow_buf_copy(abd_t *, size_t);
107 void abd_return_buf(abd_t *, void *, size_t);
108 void abd_return_buf_copy(abd_t *, void *, size_t);
109 void abd_take_ownership_of_buf(abd_t *, boolean_t);
110 void abd_release_ownership_of_buf(abd_t *);
111 
112 /*
113  * ABD operations
114  */
115 
116 int abd_iterate_func(abd_t *, size_t, size_t, abd_iter_func_t *, void *);
117 int abd_iterate_func2(abd_t *, abd_t *, size_t, size_t, size_t,
118     abd_iter_func2_t *, void *);
119 void abd_copy_off(abd_t *, abd_t *, size_t, size_t, size_t);
120 void abd_copy_from_buf_off(abd_t *, const void *, size_t, size_t);
121 void abd_copy_to_buf_off(void *, abd_t *, size_t, size_t);
122 int abd_cmp(abd_t *, abd_t *);
123 int abd_cmp_buf_off(abd_t *, const void *, size_t, size_t);
124 int abd_cmp_zero_off(abd_t *, size_t, size_t);
125 void abd_zero_off(abd_t *, size_t, size_t);
126 void abd_verify(abd_t *);
127 
128 void abd_raidz_gen_iterate(abd_t **cabds, abd_t *dabd, size_t off,
129 	size_t csize, size_t dsize, const unsigned parity,
130 	void (*func_raidz_gen)(void **, const void *, size_t, size_t));
131 void abd_raidz_rec_iterate(abd_t **cabds, abd_t **tabds,
132 	size_t tsize, const unsigned parity,
133 	void (*func_raidz_rec)(void **t, const size_t tsize, void **c,
134 	const unsigned *mul),
135 	const unsigned *mul);
136 
137 /*
138  * Wrappers for calls with offsets of 0
139  */
140 
141 static inline void
abd_copy(abd_t * dabd,abd_t * sabd,size_t size)142 abd_copy(abd_t *dabd, abd_t *sabd, size_t size)
143 {
144 	abd_copy_off(dabd, sabd, 0, 0, size);
145 }
146 
147 static inline void
abd_copy_from_buf(abd_t * abd,const void * buf,size_t size)148 abd_copy_from_buf(abd_t *abd, const void *buf, size_t size)
149 {
150 	abd_copy_from_buf_off(abd, buf, 0, size);
151 }
152 
153 static inline void
abd_copy_to_buf(void * buf,abd_t * abd,size_t size)154 abd_copy_to_buf(void* buf, abd_t *abd, size_t size)
155 {
156 	abd_copy_to_buf_off(buf, abd, 0, size);
157 }
158 
159 static inline int
abd_cmp_buf(abd_t * abd,const void * buf,size_t size)160 abd_cmp_buf(abd_t *abd, const void *buf, size_t size)
161 {
162 	return (abd_cmp_buf_off(abd, buf, 0, size));
163 }
164 
165 static inline void
abd_zero(abd_t * abd,size_t size)166 abd_zero(abd_t *abd, size_t size)
167 {
168 	abd_zero_off(abd, 0, size);
169 }
170 
171 static inline int
abd_cmp_zero(abd_t * abd,size_t size)172 abd_cmp_zero(abd_t *abd, size_t size)
173 {
174 	return (abd_cmp_zero_off(abd, 0, size));
175 }
176 
177 /*
178  * ABD type check functions
179  */
180 static inline boolean_t
abd_is_linear(abd_t * abd)181 abd_is_linear(abd_t *abd)
182 {
183 	return ((abd->abd_flags & ABD_FLAG_LINEAR) ? B_TRUE : B_FALSE);
184 }
185 
186 static inline boolean_t
abd_is_linear_page(abd_t * abd)187 abd_is_linear_page(abd_t *abd)
188 {
189 	return ((abd->abd_flags & ABD_FLAG_LINEAR_PAGE) ? B_TRUE : B_FALSE);
190 }
191 
192 static inline boolean_t
abd_is_gang(abd_t * abd)193 abd_is_gang(abd_t *abd)
194 {
195 	return ((abd->abd_flags & ABD_FLAG_GANG) ? B_TRUE : B_FALSE);
196 }
197 
198 static inline uint_t
abd_get_size(abd_t * abd)199 abd_get_size(abd_t *abd)
200 {
201 	return (abd->abd_size);
202 }
203 
204 static inline boolean_t
abd_is_from_pages(abd_t * abd)205 abd_is_from_pages(abd_t *abd)
206 {
207 	return ((abd->abd_flags & ABD_FLAG_FROM_PAGES) ? B_TRUE : B_FALSE);
208 }
209 
210 /*
211  * Module lifecycle
212  * Defined in each specific OS's abd_os.c
213  */
214 
215 void abd_init(void);
216 void abd_fini(void);
217 
218 #ifdef __cplusplus
219 }
220 #endif
221 
222 #endif	/* _ABD_H */
223