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 * Copyright (c) 2023, 2024, Klara Inc. 25 */ 26 27 #ifndef _ABD_IMPL_H 28 #define _ABD_IMPL_H 29 30 #include <sys/abd.h> 31 #include <sys/wmsum.h> 32 33 #ifdef __cplusplus 34 extern "C" { 35 #endif 36 37 typedef enum abd_stats_op { 38 ABDSTAT_INCR, /* Increase abdstat values */ 39 ABDSTAT_DECR /* Decrease abdstat values */ 40 } abd_stats_op_t; 41 42 /* forward declarations */ 43 struct scatterlist; 44 struct page; 45 46 struct abd_iter { 47 /* public interface */ 48 union { 49 /* for abd_iter_map()/abd_iter_unmap() */ 50 struct { 51 /* addr corresponding to iter_pos */ 52 void *iter_mapaddr; 53 /* length of data valid at mapaddr */ 54 size_t iter_mapsize; 55 }; 56 /* for abd_iter_page() */ 57 struct { 58 /* current page */ 59 struct page *iter_page; 60 /* offset of data in page */ 61 size_t iter_page_doff; 62 /* size of data in page */ 63 size_t iter_page_dsize; 64 }; 65 }; 66 67 /* private */ 68 abd_t *iter_abd; /* ABD being iterated through */ 69 size_t iter_pos; 70 size_t iter_offset; /* offset in current sg/abd_buf, */ 71 /* abd_offset included */ 72 struct scatterlist *iter_sg; /* current sg */ 73 }; 74 75 extern abd_t *abd_zero_scatter; 76 77 abd_t *abd_gang_get_offset(abd_t *, size_t *); 78 abd_t *abd_alloc_struct(size_t); 79 void abd_free_struct(abd_t *); 80 81 /* 82 * OS specific functions 83 */ 84 85 abd_t *abd_alloc_struct_impl(size_t); 86 abd_t *abd_get_offset_scatter(abd_t *, abd_t *, size_t, size_t); 87 void abd_free_struct_impl(abd_t *); 88 void abd_alloc_chunks(abd_t *, size_t); 89 void abd_free_chunks(abd_t *); 90 void abd_update_scatter_stats(abd_t *, abd_stats_op_t); 91 void abd_update_linear_stats(abd_t *, abd_stats_op_t); 92 void abd_verify_scatter(abd_t *); 93 void abd_free_linear_page(abd_t *); 94 /* OS specific abd_iter functions */ 95 void abd_iter_init(struct abd_iter *, abd_t *); 96 boolean_t abd_iter_at_end(struct abd_iter *); 97 void abd_iter_advance(struct abd_iter *, size_t); 98 void abd_iter_map(struct abd_iter *); 99 void abd_iter_unmap(struct abd_iter *); 100 void abd_iter_page(struct abd_iter *); 101 102 /* 103 * Helper macros 104 */ 105 #define ABDSTAT_INCR(stat, val) \ 106 wmsum_add(&abd_sums.stat, (val)) 107 #define ABDSTAT_BUMP(stat) ABDSTAT_INCR(stat, 1) 108 #define ABDSTAT_BUMPDOWN(stat) ABDSTAT_INCR(stat, -1) 109 110 #define ABD_SCATTER(abd) (abd->abd_u.abd_scatter) 111 #define ABD_LINEAR_BUF(abd) (abd->abd_u.abd_linear.abd_buf) 112 #define ABD_GANG(abd) (abd->abd_u.abd_gang) 113 114 #if defined(_KERNEL) 115 #if defined(__FreeBSD__) 116 #define abd_enter_critical(flags) critical_enter() 117 #define abd_exit_critical(flags) critical_exit() 118 #else 119 #define abd_enter_critical(flags) local_irq_save(flags) 120 #define abd_exit_critical(flags) local_irq_restore(flags) 121 #endif 122 #else /* !_KERNEL */ 123 #define abd_enter_critical(flags) ((void)0) 124 #define abd_exit_critical(flags) ((void)0) 125 #endif 126 127 #ifdef __cplusplus 128 } 129 #endif 130 131 #endif /* _ABD_IMPL_H */ 132