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 2006 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #ifndef _SYS_MODHASH_IMPL_H 27 #define _SYS_MODHASH_IMPL_H 28 29 /* 30 * Internal details for the kernel's generic hash implementation. 31 */ 32 33 #ifdef __cplusplus 34 extern "C" { 35 #endif 36 37 #include <sys/zfs_context.h> 38 #include <sys/modhash.h> 39 40 struct mod_hash_entry { 41 mod_hash_key_t mhe_key; /* stored hash key */ 42 mod_hash_val_t mhe_val; /* stored hash value */ 43 struct mod_hash_entry *mhe_next; /* next item in chain */ 44 }; 45 46 struct mod_hash_stat { 47 ulong_t mhs_hit; /* tried a 'find' and it succeeded */ 48 ulong_t mhs_miss; /* tried a 'find' but it failed */ 49 ulong_t mhs_coll; /* occur when insert fails because of dup's */ 50 ulong_t mhs_nelems; /* total number of stored key/value pairs */ 51 ulong_t mhs_nomem; /* number of times kmem_alloc failed */ 52 }; 53 54 struct mod_hash { 55 krwlock_t mh_contents; /* lock protecting contents */ 56 char *mh_name; /* hash name */ 57 int mh_sleep; /* kmem_alloc flag */ 58 size_t mh_nchains; /* # of elements in mh_entries */ 59 60 /* key and val destructor */ 61 void (*mh_kdtor)(mod_hash_key_t); 62 void (*mh_vdtor)(mod_hash_val_t); 63 64 /* key comparator */ 65 int (*mh_keycmp)(mod_hash_key_t, mod_hash_key_t); 66 67 /* hash algorithm, and algorithm-private data */ 68 uint_t (*mh_hashalg)(void *, mod_hash_key_t); 69 void *mh_hashalg_data; 70 71 struct mod_hash *mh_next; /* next hash in list */ 72 73 struct mod_hash_stat mh_stat; 74 75 struct mod_hash_entry *mh_entries[1]; 76 }; 77 78 /* 79 * MH_SIZE() 80 * Compute the size of a mod_hash_t, in bytes, given the number of 81 * elements it contains. 82 */ 83 #define MH_SIZE(n) \ 84 (sizeof (mod_hash_t) + ((n) - 1) * (sizeof (struct mod_hash_entry *))) 85 86 /* 87 * Module initialization; called once. 88 */ 89 void mod_hash_fini(void); 90 void mod_hash_init(void); 91 92 /* 93 * Internal routines. Use directly with care. 94 */ 95 uint_t i_mod_hash(mod_hash_t *, mod_hash_key_t); 96 int i_mod_hash_insert_nosync(mod_hash_t *, mod_hash_key_t, mod_hash_val_t, 97 mod_hash_hndl_t); 98 int i_mod_hash_remove_nosync(mod_hash_t *, mod_hash_key_t, mod_hash_val_t *); 99 int i_mod_hash_find_nosync(mod_hash_t *, mod_hash_key_t, mod_hash_val_t *); 100 void i_mod_hash_walk_nosync(mod_hash_t *, uint_t (*)(mod_hash_key_t, 101 mod_hash_val_t *, void *), void *); 102 void i_mod_hash_clear_nosync(mod_hash_t *hash); 103 104 #ifdef __cplusplus 105 } 106 #endif 107 108 #endif /* _SYS_MODHASH_IMPL_H */ 109