1 /* 2 * Copyright (c) 2007 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 /* 35 * System resource registration, reference counter, and allocation 36 * management subsystem. 37 * 38 * All major system resources use this structure and API to associate 39 * a machine-unique sysid with a major system resource structure, to 40 * reference count that structure, to register the structure and provide 41 * a dictionary lookup feature for remote access. 42 * 43 * System resources are backed by the objcache. 44 */ 45 46 #ifndef _SYS_SYSREF_H_ 47 #define _SYS_SYSREF_H_ 48 49 #ifndef _SYS_SYSID_H_ 50 #include <sys/sysid.h> 51 #endif 52 #ifndef _SYS_TREE_H_ 53 #include <sys/tree.h> 54 #endif 55 #ifndef _SYS_OBJCACHE_H_ 56 #include <sys/objcache.h> 57 #endif 58 59 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) 60 #ifndef _SYS__MALLOC_H_ 61 #include <sys/_malloc.h> 62 #endif 63 64 /* 65 * Register a resource structure type. Note that the destroy function 66 * will be called on 1->0 transitions (really 1->-0x40000000 transitions), 67 * and the free function 68 * but the free function can be called via an IPI, without the BGL, and 69 * must be carefully coded if it does anything more complex then objcache_put 70 */ 71 typedef void (*sysref_terminate_func_t)(void *); 72 typedef void (*sysref_lock_func_t)(void *); 73 typedef void (*sysref_unlock_func_t)(void *); 74 75 struct sysref_class { 76 const char *name; /* name of the system resource */ 77 malloc_type_t mtype; /* malloc backing store */ 78 int proto; /* RPC protocol id */ 79 int offset; /* offset of sysref in resource */ 80 int objsize; /* size of the resource structure */ 81 int nom_cache; /* nominal objects to cache */ 82 int flags; 83 struct objcache *oc; /* object cache */ 84 objcache_ctor_fn *ctor; /* objcache ctor chaining */ 85 objcache_dtor_fn *dtor; /* objcache dtor chaining */ 86 struct sysref_ops { 87 sysref_terminate_func_t terminate; 88 sysref_lock_func_t lock; 89 sysref_unlock_func_t unlock; 90 } ops; 91 }; 92 93 #define SRC_MANAGEDINIT 0x0001 /* do not auto-zero the resource */ 94 95 /* 96 * sysref - embedded in resource structures. 97 * 98 * NOTE: The cpuid determining which cpu's RB tree the sysref is 99 * associated with is integrated into the sysref. 100 * 101 * NOTE: A resource can be in varying states of construction or 102 * deconstruction, denoted by having a negative refcnt. To keep 103 * performance nominal we reuse sysids that are NOT looked up via 104 * syslink (meaning we don't have to adjust their location in the 105 * RB tree). The objcache is used to cache the RB tree linkage. 106 */ 107 struct sysref { 108 RB_ENTRY(sysref) rbnode; /* per-cpu red-black tree node */ 109 sysid_t sysid; /* machine-wide unique sysid */ 110 int refcnt; /* normal reference count */ 111 int flags; 112 struct sysref_class *srclass; /* type of resource and API */ 113 }; 114 115 #define SRF_SYSIDUSED 0x0001 /* sysid was used for access */ 116 #define SRF_ALLOCATED 0x0002 /* sysref_alloc used to allocate */ 117 #define SRF_PUTAWAY 0x0004 /* in objcache */ 118 119 RB_HEAD(sysref_rb_tree, sysref); 120 RB_PROTOTYPE2(sysref_rb_tree, sysref, rbnode, rb_sysref_compare, sysid_t); 121 122 #endif /* _KERNEL || _KERNEL_STRUCTURES */ 123 124 /* 125 * Protocol numbers 126 */ 127 #define SYSREF_PROTO_VMSPACE 0x0020 128 #define SYSREF_PROTO_VMOBJECT 0x0021 129 #define SYSREF_PROTO_VNODE 0x0022 130 #define SYSREF_PROTO_PROCESS 0x0023 131 #define SYSREF_PROTO_LWP 0x0024 132 #define SYSREF_PROTO_FD 0x0025 133 #define SYSREF_PROTO_FP 0x0026 134 #define SYSREF_PROTO_SOCKET 0x0027 135 #define SYSREF_PROTO_NCP 0x0028 136 #define SYSREF_PROTO_BUF 0x0029 137 #define SYSREF_PROTO_FSMOUNT 0x002A 138 #define SYSREF_PROTO_DEV 0x002B 139 140 #ifdef _KERNEL 141 142 sysid_t allocsysid(void); 143 144 #endif 145 146 #endif /* !_SYS_SYSREF_H_ */ 147