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 zfs_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_offset_size(abd_t *, size_t, size_t); 77 abd_t *abd_get_from_buf(void *, size_t); 78 void abd_put(abd_t *); 79 80 /* 81 * Conversion to and from a normal buffer 82 */ 83 84 void *abd_to_buf(abd_t *); 85 void *abd_borrow_buf(abd_t *, size_t); 86 void *abd_borrow_buf_copy(abd_t *, size_t); 87 void abd_return_buf(abd_t *, void *, size_t); 88 void abd_return_buf_copy(abd_t *, void *, size_t); 89 void abd_take_ownership_of_buf(abd_t *, boolean_t); 90 void abd_release_ownership_of_buf(abd_t *); 91 92 /* 93 * ABD operations 94 */ 95 96 int abd_iterate_func(abd_t *, size_t, size_t, abd_iter_func_t *, void *); 97 int abd_iterate_func2(abd_t *, abd_t *, size_t, size_t, size_t, 98 abd_iter_func2_t *, void *); 99 void abd_copy_off(abd_t *, abd_t *, size_t, size_t, size_t); 100 void abd_copy_from_buf_off(abd_t *, const void *, size_t, size_t); 101 void abd_copy_to_buf_off(void *, abd_t *, size_t, size_t); 102 int abd_cmp(abd_t *, abd_t *, size_t); 103 int abd_cmp_buf_off(abd_t *, const void *, size_t, size_t); 104 void abd_zero_off(abd_t *, size_t, size_t); 105 106 /* 107 * Wrappers for calls with offsets of 0 108 */ 109 110 inline void 111 abd_copy(abd_t *dabd, abd_t *sabd, size_t size) 112 { 113 abd_copy_off(dabd, sabd, 0, 0, size); 114 } 115 116 inline void 117 abd_copy_from_buf(abd_t *abd, const void *buf, size_t size) 118 { 119 abd_copy_from_buf_off(abd, buf, 0, size); 120 } 121 122 inline void 123 abd_copy_to_buf(void* buf, abd_t *abd, size_t size) 124 { 125 abd_copy_to_buf_off(buf, abd, 0, size); 126 } 127 128 inline int 129 abd_cmp_buf(abd_t *abd, const void *buf, size_t size) 130 { 131 return (abd_cmp_buf_off(abd, buf, 0, size)); 132 } 133 134 inline void 135 abd_zero(abd_t *abd, size_t size) 136 { 137 abd_zero_off(abd, 0, size); 138 } 139 140 /* 141 * Module lifecycle 142 */ 143 144 void abd_init(void); 145 void abd_fini(void); 146 147 #ifdef __cplusplus 148 } 149 #endif 150 151 #endif /* _ABD_H */ 152