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 34 #ifdef __cplusplus 35 extern "C" { 36 #endif 37 38 typedef 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 51 typedef 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 void *abd_chunks[1]; /* actually variable-length */ 65 #else 66 uint_t abd_nents; 67 struct scatterlist *abd_sgl; 68 #endif 69 } abd_scatter; 70 struct abd_linear { 71 void *abd_buf; 72 struct scatterlist *abd_sgl; /* for LINEAR_PAGE */ 73 } abd_linear; 74 struct abd_gang { 75 list_t abd_gang_chain; 76 } abd_gang; 77 } abd_u; 78 } abd_t; 79 80 typedef int abd_iter_func_t(void *buf, size_t len, void *priv); 81 typedef int abd_iter_func2_t(void *bufa, void *bufb, size_t len, void *priv); 82 #if defined(__linux__) && defined(_KERNEL) 83 typedef int abd_iter_page_func_t(struct page *, size_t, size_t, void *); 84 #endif 85 86 extern int zfs_abd_scatter_enabled; 87 88 /* 89 * Allocations and deallocations 90 */ 91 92 __attribute__((malloc)) 93 abd_t *abd_alloc(size_t, boolean_t); 94 __attribute__((malloc)) 95 abd_t *abd_alloc_linear(size_t, boolean_t); 96 __attribute__((malloc)) 97 abd_t *abd_alloc_gang(void); 98 __attribute__((malloc)) 99 abd_t *abd_alloc_for_io(size_t, boolean_t); 100 __attribute__((malloc)) 101 abd_t *abd_alloc_sametype(abd_t *, size_t); 102 boolean_t abd_size_alloc_linear(size_t); 103 void abd_gang_add(abd_t *, abd_t *, boolean_t); 104 void abd_free(abd_t *); 105 abd_t *abd_get_offset(abd_t *, size_t); 106 abd_t *abd_get_offset_size(abd_t *, size_t, size_t); 107 abd_t *abd_get_offset_struct(abd_t *, abd_t *, size_t, size_t); 108 abd_t *abd_get_zeros(size_t); 109 abd_t *abd_get_from_buf(void *, size_t); 110 void abd_cache_reap_now(void); 111 112 /* 113 * Conversion to and from a normal buffer 114 */ 115 116 void *abd_to_buf(abd_t *); 117 void *abd_borrow_buf(abd_t *, size_t); 118 void *abd_borrow_buf_copy(abd_t *, size_t); 119 void abd_return_buf(abd_t *, void *, size_t); 120 void abd_return_buf_copy(abd_t *, void *, size_t); 121 void abd_take_ownership_of_buf(abd_t *, boolean_t); 122 void abd_release_ownership_of_buf(abd_t *); 123 124 /* 125 * ABD operations 126 */ 127 128 int abd_iterate_func(abd_t *, size_t, size_t, abd_iter_func_t *, void *); 129 int abd_iterate_func2(abd_t *, abd_t *, size_t, size_t, size_t, 130 abd_iter_func2_t *, void *); 131 #if defined(__linux__) && defined(_KERNEL) 132 int abd_iterate_page_func(abd_t *, size_t, size_t, abd_iter_page_func_t *, 133 void *); 134 #endif 135 void abd_copy_off(abd_t *, abd_t *, size_t, size_t, size_t); 136 void abd_copy_from_buf_off(abd_t *, const void *, size_t, size_t); 137 void abd_copy_to_buf_off(void *, abd_t *, size_t, size_t); 138 int abd_cmp(abd_t *, abd_t *); 139 int abd_cmp_buf_off(abd_t *, const void *, size_t, size_t); 140 void abd_zero_off(abd_t *, size_t, size_t); 141 void abd_verify(abd_t *); 142 143 void abd_raidz_gen_iterate(abd_t **cabds, abd_t *dabd, size_t off, 144 size_t csize, size_t dsize, const unsigned parity, 145 void (*func_raidz_gen)(void **, const void *, size_t, size_t)); 146 void abd_raidz_rec_iterate(abd_t **cabds, abd_t **tabds, 147 size_t tsize, const unsigned parity, 148 void (*func_raidz_rec)(void **t, const size_t tsize, void **c, 149 const unsigned *mul), 150 const unsigned *mul); 151 152 /* 153 * Wrappers for calls with offsets of 0 154 */ 155 156 static inline void 157 abd_copy(abd_t *dabd, abd_t *sabd, size_t size) 158 { 159 abd_copy_off(dabd, sabd, 0, 0, size); 160 } 161 162 static inline void 163 abd_copy_from_buf(abd_t *abd, const void *buf, size_t size) 164 { 165 abd_copy_from_buf_off(abd, buf, 0, size); 166 } 167 168 static inline void 169 abd_copy_to_buf(void* buf, abd_t *abd, size_t size) 170 { 171 abd_copy_to_buf_off(buf, abd, 0, size); 172 } 173 174 static inline int 175 abd_cmp_buf(abd_t *abd, const void *buf, size_t size) 176 { 177 return (abd_cmp_buf_off(abd, buf, 0, size)); 178 } 179 180 static inline void 181 abd_zero(abd_t *abd, size_t size) 182 { 183 abd_zero_off(abd, 0, size); 184 } 185 186 /* 187 * ABD type check functions 188 */ 189 static inline boolean_t 190 abd_is_linear(abd_t *abd) 191 { 192 return ((abd->abd_flags & ABD_FLAG_LINEAR) ? B_TRUE : B_FALSE); 193 } 194 195 static inline boolean_t 196 abd_is_linear_page(abd_t *abd) 197 { 198 return ((abd->abd_flags & ABD_FLAG_LINEAR_PAGE) ? B_TRUE : B_FALSE); 199 } 200 201 static inline boolean_t 202 abd_is_gang(abd_t *abd) 203 { 204 return ((abd->abd_flags & ABD_FLAG_GANG) ? B_TRUE : B_FALSE); 205 } 206 207 static inline uint_t 208 abd_get_size(abd_t *abd) 209 { 210 return (abd->abd_size); 211 } 212 213 /* 214 * Module lifecycle 215 * Defined in each specific OS's abd_os.c 216 */ 217 218 void abd_init(void); 219 void abd_fini(void); 220 221 /* 222 * Linux ABD bio functions 223 * Note: these are only needed to support vdev_classic. See comment in 224 * vdev_disk.c. 225 */ 226 #if defined(__linux__) && defined(_KERNEL) 227 unsigned int abd_bio_map_off(struct bio *, abd_t *, unsigned int, size_t); 228 unsigned long abd_nr_pages_off(abd_t *, unsigned int, size_t); 229 #endif 230 231 #ifdef __cplusplus 232 } 233 #endif 234 235 #endif /* _ABD_H */ 236