1 /* 2 * This file and its contents are supplied under the terms of the 3 * Common Development and Distribution License ("CDDL"), version 1.0. 4 * You may only use this file in accordance with the terms of version 5 * 1.0 of the CDDL. 6 * 7 * A full copy of the text of the CDDL should have accompanied this 8 * source. A copy of the CDDL is also available via the Internet at 9 * http://www.illumos.org/license/CDDL. 10 */ 11 12 /* 13 * Copyright (c) 2014 by Chunwei Chen. All rights reserved. 14 * Copyright (c) 2016 by Delphix. All rights reserved. 15 */ 16 17 #ifndef _ABD_H 18 #define _ABD_H 19 20 #include <sys/isa_defs.h> 21 #include <sys/int_types.h> 22 #include <sys/debug.h> 23 #include <sys/refcount.h> 24 #ifdef _KERNEL 25 #include <sys/uio.h> 26 #endif 27 28 #ifdef __cplusplus 29 extern "C" { 30 #endif 31 32 typedef enum abd_flags { 33 ABD_FLAG_LINEAR = 1 << 0, /* is buffer linear (or scattered)? */ 34 ABD_FLAG_OWNER = 1 << 1, /* does it own its data buffers? */ 35 ABD_FLAG_META = 1 << 2 /* does this represent FS metadata? */ 36 } abd_flags_t; 37 38 typedef struct abd { 39 abd_flags_t abd_flags; 40 uint_t abd_size; /* excludes scattered abd_offset */ 41 struct abd *abd_parent; 42 refcount_t abd_children; 43 union { 44 struct abd_scatter { 45 uint_t abd_offset; 46 uint_t abd_chunk_size; 47 void *abd_chunks[]; 48 } abd_scatter; 49 struct abd_linear { 50 void *abd_buf; 51 } abd_linear; 52 } abd_u; 53 } abd_t; 54 55 typedef int abd_iter_func_t(void *, size_t, void *); 56 typedef int abd_iter_func2_t(void *, void *, size_t, void *); 57 58 extern boolean_t zfs_abd_scatter_enabled; 59 60 inline boolean_t 61 abd_is_linear(abd_t *abd) 62 { 63 return ((abd->abd_flags & ABD_FLAG_LINEAR) != 0 ? B_TRUE : B_FALSE); 64 } 65 66 /* 67 * Allocations and deallocations 68 */ 69 70 abd_t *abd_alloc(size_t, boolean_t); 71 abd_t *abd_alloc_linear(size_t, boolean_t); 72 abd_t *abd_alloc_for_io(size_t, boolean_t); 73 abd_t *abd_alloc_sametype(abd_t *, size_t); 74 void abd_free(abd_t *); 75 abd_t *abd_get_offset(abd_t *, size_t); 76 abd_t *abd_get_from_buf(void *, size_t); 77 void abd_put(abd_t *); 78 79 /* 80 * Conversion to and from a normal buffer 81 */ 82 83 void *abd_to_buf(abd_t *); 84 void *abd_borrow_buf(abd_t *, size_t); 85 void *abd_borrow_buf_copy(abd_t *, size_t); 86 void abd_return_buf(abd_t *, void *, size_t); 87 void abd_return_buf_copy(abd_t *, void *, size_t); 88 void abd_take_ownership_of_buf(abd_t *, boolean_t); 89 void abd_release_ownership_of_buf(abd_t *); 90 91 /* 92 * ABD operations 93 */ 94 95 int abd_iterate_func(abd_t *, size_t, size_t, abd_iter_func_t *, void *); 96 int abd_iterate_func2(abd_t *, abd_t *, size_t, size_t, size_t, 97 abd_iter_func2_t *, void *); 98 void abd_copy_off(abd_t *, abd_t *, size_t, size_t, size_t); 99 void abd_copy_from_buf_off(abd_t *, const void *, size_t, size_t); 100 void abd_copy_to_buf_off(void *, abd_t *, size_t, size_t); 101 int abd_cmp(abd_t *, abd_t *, size_t); 102 int abd_cmp_buf_off(abd_t *, const void *, size_t, size_t); 103 void abd_zero_off(abd_t *, size_t, size_t); 104 105 /* 106 * Wrappers for calls with offsets of 0 107 */ 108 109 inline void 110 abd_copy(abd_t *dabd, abd_t *sabd, size_t size) 111 { 112 abd_copy_off(dabd, sabd, 0, 0, size); 113 } 114 115 inline void 116 abd_copy_from_buf(abd_t *abd, const void *buf, size_t size) 117 { 118 abd_copy_from_buf_off(abd, buf, 0, size); 119 } 120 121 inline void 122 abd_copy_to_buf(void* buf, abd_t *abd, size_t size) 123 { 124 abd_copy_to_buf_off(buf, abd, 0, size); 125 } 126 127 inline int 128 abd_cmp_buf(abd_t *abd, const void *buf, size_t size) 129 { 130 return (abd_cmp_buf_off(abd, buf, 0, size)); 131 } 132 133 inline void 134 abd_zero(abd_t *abd, size_t size) 135 { 136 abd_zero_off(abd, 0, size); 137 } 138 139 /* 140 * Module lifecycle 141 */ 142 143 void abd_init(void); 144 void abd_fini(void); 145 146 #ifdef __cplusplus 147 } 148 #endif 149 150 #endif /* _ABD_H */ 151