| 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 | * $DragonFly: src/sys/sys/sysref.h,v 1.2 2007/05/08 02:31:43 dillon Exp $ |
| 35 | */ |
| 36 | /* |
| 37 | * System resource registration, reference counter, and allocation |
| 38 | * management subsystem. |
| 39 | * |
| 40 | * All major system resources use this structure and API to associate |
| 41 | * a machine-unique sysid with a major system resource structure, to |
| 42 | * reference count that structure, to register the structure and provide |
| 43 | * a dictionary lookup feature for remote access. |
| 44 | * |
| 45 | * System resources are backed by the objcache. |
| 46 | */ |
| 47 | |
| 48 | #ifndef _SYS_SYSREF_H_ |
| 49 | #define _SYS_SYSREF_H_ |
| 50 | |
| 51 | #ifndef _SYS_SYSID_H_ |
| 52 | #include <sys/sysid.h> |
| 53 | #endif |
| 54 | #ifndef _SYS_TREE_H_ |
| 55 | #include <sys/tree.h> |
| 56 | #endif |
| 57 | #ifndef _SYS_OBJCACHE_H_ |
| 58 | #include <sys/objcache.h> |
| 59 | #endif |
| 60 | #ifndef _SYS_MALLOC_H_ |
| 61 | #include <sys/malloc.h> |
| 62 | #endif |
| 63 | |
| 64 | #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) |
| 65 | |
| 66 | /* |
| 67 | * Register a resource structure type. Note that the destroy function |
| 68 | * will be called on 1->0 transitions (really 1->-0x40000000 transitions), |
| 69 | * and the free function |
| 70 | * but the free function can be called via an IPI, without the BGL, and |
| 71 | * must be carefully coded if it does anything more complex then objcache_put |
| 72 | */ |
| 73 | typedef void (*sysref_terminate_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 mag_capacity; /* magazine capacity init (def 64) */ |
| 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 | } ops; |
| 89 | }; |
| 90 | |
| 91 | #define SRC_MANAGEDINIT 0x0001 /* do not auto-zero the resource */ |
| 92 | |
| 93 | /* |
| 94 | * sysref - embedded in resource structures. |
| 95 | * |
| 96 | * NOTE: The cpuid determining which cpu's RB tree the sysref is |
| 97 | * associated with is integrated into the sysref. |
| 98 | * |
| 99 | * NOTE: A resource can be in varying states of construction or |
| 100 | * deconstruction, denoted by having a negative refcnt. To keep |
| 101 | * performance nominal we reuse sysids that are NOT looked up via |
| 102 | * syslink (meaning we don't have to adjust their location in the |
| 103 | * RB tree). The objcache is used to cache the RB tree linkage. |
| 104 | */ |
| 105 | struct sysref { |
| 106 | RB_ENTRY(sysref) rbnode; /* per-cpu red-black tree node */ |
| 107 | sysid_t sysid; /* machine-wide unique sysid */ |
| 108 | int refcnt; /* normal reference count */ |
| 109 | int flags; |
| 110 | struct sysref_class *class; /* type of resource and API */ |
| 111 | }; |
| 112 | |
| 113 | #define SRF_SYSIDUSED 0x0001 /* sysid was used for access */ |
| 114 | #define SRF_ALLOCATED 0x0002 /* sysref_alloc used to allocate */ |
| 115 | |
| 116 | RB_HEAD(sysref_rb_tree, sysref); |
| 117 | RB_PROTOTYPE2(sysref_rb_tree, sysref, rbnode, rb_sysref_compare, sysid_t); |
| 118 | |
| 119 | #endif |
| 120 | |
| 121 | /* |
| 122 | * Protocol numbers |
| 123 | */ |
| 124 | #define SYSREF_PROTO_VMSPACE 0x0020 |
| 125 | #define SYSREF_PROTO_VMOBJECT 0x0021 |
| 126 | #define SYSREF_PROTO_VNODE 0x0022 |
| 127 | #define SYSREF_PROTO_PROCESS 0x0023 |
| 128 | #define SYSREF_PROTO_LWP 0x0024 |
| 129 | #define SYSREF_PROTO_FD 0x0025 |
| 130 | #define SYSREF_PROTO_FP 0x0026 |
| 131 | #define SYSREF_PROTO_SOCKET 0x0027 |
| 132 | #define SYSREF_PROTO_NCP 0x0028 |
| 133 | #define SYSREF_PROTO_BUF 0x0029 |
| 134 | #define SYSREF_PROTO_FSMOUNT 0x002A |
| 135 | #define SYSREF_PROTO_DEV 0x002B |
| 136 | |
| 137 | #endif |