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