dmover_backend.c revision 1.2.2.2
1 1.2.2.2 thorpej /* $NetBSD: dmover_backend.c,v 1.2.2.2 2002/12/29 20:49:15 thorpej Exp $ */ 2 1.2.2.2 thorpej 3 1.2.2.2 thorpej /* 4 1.2.2.2 thorpej * Copyright (c) 2002 Wasabi Systems, Inc. 5 1.2.2.2 thorpej * All rights reserved. 6 1.2.2.2 thorpej * 7 1.2.2.2 thorpej * Written by Jason R. Thorpe for Wasabi Systems, Inc. 8 1.2.2.2 thorpej * 9 1.2.2.2 thorpej * Redistribution and use in source and binary forms, with or without 10 1.2.2.2 thorpej * modification, are permitted provided that the following conditions 11 1.2.2.2 thorpej * are met: 12 1.2.2.2 thorpej * 1. Redistributions of source code must retain the above copyright 13 1.2.2.2 thorpej * notice, this list of conditions and the following disclaimer. 14 1.2.2.2 thorpej * 2. Redistributions in binary form must reproduce the above copyright 15 1.2.2.2 thorpej * notice, this list of conditions and the following disclaimer in the 16 1.2.2.2 thorpej * documentation and/or other materials provided with the distribution. 17 1.2.2.2 thorpej * 3. All advertising materials mentioning features or use of this software 18 1.2.2.2 thorpej * must display the following acknowledgement: 19 1.2.2.2 thorpej * This product includes software developed for the NetBSD Project by 20 1.2.2.2 thorpej * Wasabi Systems, Inc. 21 1.2.2.2 thorpej * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 1.2.2.2 thorpej * or promote products derived from this software without specific prior 23 1.2.2.2 thorpej * written permission. 24 1.2.2.2 thorpej * 25 1.2.2.2 thorpej * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 1.2.2.2 thorpej * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 1.2.2.2 thorpej * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 1.2.2.2 thorpej * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 1.2.2.2 thorpej * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 1.2.2.2 thorpej * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 1.2.2.2 thorpej * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 1.2.2.2 thorpej * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 1.2.2.2 thorpej * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 1.2.2.2 thorpej * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 1.2.2.2 thorpej * POSSIBILITY OF SUCH DAMAGE. 36 1.2.2.2 thorpej */ 37 1.2.2.2 thorpej 38 1.2.2.2 thorpej /* 39 1.2.2.2 thorpej * dmover_backend.c: Backend management functions for dmover-api. 40 1.2.2.2 thorpej */ 41 1.2.2.2 thorpej 42 1.2.2.2 thorpej #include <sys/cdefs.h> 43 1.2.2.2 thorpej __KERNEL_RCSID(0, "$NetBSD: dmover_backend.c,v 1.2.2.2 2002/12/29 20:49:15 thorpej Exp $"); 44 1.2.2.2 thorpej 45 1.2.2.2 thorpej #include <sys/param.h> 46 1.2.2.2 thorpej #include <sys/lock.h> 47 1.2.2.2 thorpej #include <sys/systm.h> 48 1.2.2.2 thorpej 49 1.2.2.2 thorpej #include <dev/dmover/dmovervar.h> 50 1.2.2.2 thorpej 51 1.2.2.2 thorpej TAILQ_HEAD(, dmover_backend) dmover_backend_list; 52 1.2.2.2 thorpej struct lock dmover_backend_list_lock; 53 1.2.2.2 thorpej 54 1.2.2.2 thorpej #define BACKEND_LIST_LOCK_READ() \ 55 1.2.2.2 thorpej do { \ 56 1.2.2.2 thorpej (void) spinlockmgr(&dmover_backend_list_lock, LK_SHARED, NULL); \ 57 1.2.2.2 thorpej } while (/*CONSTCOND*/0) 58 1.2.2.2 thorpej 59 1.2.2.2 thorpej #define BACKEND_LIST_UNLOCK_READ() \ 60 1.2.2.2 thorpej do { \ 61 1.2.2.2 thorpej (void) spinlockmgr(&dmover_backend_list_lock, LK_RELEASE, NULL);\ 62 1.2.2.2 thorpej } while (/*CONSTCOND*/0) 63 1.2.2.2 thorpej 64 1.2.2.2 thorpej #define BACKEND_LIST_LOCK_WRITE(s) \ 65 1.2.2.2 thorpej do { \ 66 1.2.2.2 thorpej (s) = splbio(); \ 67 1.2.2.2 thorpej (void) spinlockmgr(&dmover_backend_list_lock, LK_EXCLUSIVE, NULL); \ 68 1.2.2.2 thorpej } while (/*CONSTCOND*/0) 69 1.2.2.2 thorpej 70 1.2.2.2 thorpej #define BACKEND_LIST_UNLOCK_WRITE(s) \ 71 1.2.2.2 thorpej do { \ 72 1.2.2.2 thorpej (void) spinlockmgr(&dmover_backend_list_lock, LK_RELEASE, NULL);\ 73 1.2.2.2 thorpej splx((s)); \ 74 1.2.2.2 thorpej } while (/*CONSTCOND*/0) 75 1.2.2.2 thorpej 76 1.2.2.2 thorpej static int initialized; 77 1.2.2.2 thorpej static struct simplelock initialized_slock = SIMPLELOCK_INITIALIZER; 78 1.2.2.2 thorpej 79 1.2.2.2 thorpej static void 80 1.2.2.2 thorpej initialize(void) 81 1.2.2.2 thorpej { 82 1.2.2.2 thorpej 83 1.2.2.2 thorpej simple_lock(&initialized_slock); 84 1.2.2.2 thorpej if (__predict_true(initialized == 0)) { 85 1.2.2.2 thorpej TAILQ_INIT(&dmover_backend_list); 86 1.2.2.2 thorpej spinlockinit(&dmover_backend_list_lock, "dmbelk", 0); 87 1.2.2.2 thorpej 88 1.2.2.2 thorpej /* Initialize the other bits of dmover. */ 89 1.2.2.2 thorpej dmover_session_initialize(); 90 1.2.2.2 thorpej dmover_request_initialize(); 91 1.2.2.2 thorpej dmover_process_initialize(); 92 1.2.2.2 thorpej 93 1.2.2.2 thorpej initialized = 1; 94 1.2.2.2 thorpej } 95 1.2.2.2 thorpej simple_unlock(&initialized_slock); 96 1.2.2.2 thorpej } 97 1.2.2.2 thorpej 98 1.2.2.2 thorpej /* 99 1.2.2.2 thorpej * dmover_backend_register: [back-end interface function] 100 1.2.2.2 thorpej * 101 1.2.2.2 thorpej * Register a back-end with dmover-api. 102 1.2.2.2 thorpej */ 103 1.2.2.2 thorpej void 104 1.2.2.2 thorpej dmover_backend_register(struct dmover_backend *dmb) 105 1.2.2.2 thorpej { 106 1.2.2.2 thorpej int s; 107 1.2.2.2 thorpej 108 1.2.2.2 thorpej if (__predict_false(initialized == 0)) 109 1.2.2.2 thorpej initialize(); 110 1.2.2.2 thorpej 111 1.2.2.2 thorpej LIST_INIT(&dmb->dmb_sessions); 112 1.2.2.2 thorpej dmb->dmb_nsessions = 0; 113 1.2.2.2 thorpej 114 1.2.2.2 thorpej TAILQ_INIT(&dmb->dmb_pendreqs); 115 1.2.2.2 thorpej dmb->dmb_npendreqs = 0; 116 1.2.2.2 thorpej 117 1.2.2.2 thorpej BACKEND_LIST_LOCK_WRITE(s); 118 1.2.2.2 thorpej TAILQ_INSERT_TAIL(&dmover_backend_list, dmb, dmb_list); 119 1.2.2.2 thorpej BACKEND_LIST_UNLOCK_WRITE(s); 120 1.2.2.2 thorpej } 121 1.2.2.2 thorpej 122 1.2.2.2 thorpej /* 123 1.2.2.2 thorpej * dmover_backend_unregister: [back-end interface function] 124 1.2.2.2 thorpej * 125 1.2.2.2 thorpej * Un-register a back-end from dmover-api. 126 1.2.2.2 thorpej */ 127 1.2.2.2 thorpej void 128 1.2.2.2 thorpej dmover_backend_unregister(struct dmover_backend *dmb) 129 1.2.2.2 thorpej { 130 1.2.2.2 thorpej int s; 131 1.2.2.2 thorpej 132 1.2.2.2 thorpej #ifdef DIAGNOSTIC 133 1.2.2.2 thorpej if (__predict_false(initialized == 0)) { 134 1.2.2.2 thorpej int croak; 135 1.2.2.2 thorpej 136 1.2.2.2 thorpej simple_lock(&initialized_slock); 137 1.2.2.2 thorpej croak = (initialized == 0); 138 1.2.2.2 thorpej simple_unlock(&initialized_slock); 139 1.2.2.2 thorpej 140 1.2.2.2 thorpej if (croak) 141 1.2.2.2 thorpej panic("dmover_backend_unregister: not initialized"); 142 1.2.2.2 thorpej } 143 1.2.2.2 thorpej #endif 144 1.2.2.2 thorpej 145 1.2.2.2 thorpej /* XXX */ 146 1.2.2.2 thorpej if (dmb->dmb_nsessions) 147 1.2.2.2 thorpej panic("dmover_backend_unregister"); 148 1.2.2.2 thorpej 149 1.2.2.2 thorpej BACKEND_LIST_LOCK_WRITE(s); 150 1.2.2.2 thorpej TAILQ_REMOVE(&dmover_backend_list, dmb, dmb_list); 151 1.2.2.2 thorpej BACKEND_LIST_UNLOCK_WRITE(s); 152 1.2.2.2 thorpej } 153 1.2.2.2 thorpej 154 1.2.2.2 thorpej /* 155 1.2.2.2 thorpej * dmover_backend_alloc: 156 1.2.2.2 thorpej * 157 1.2.2.2 thorpej * Allocate and return a back-end on behalf of a session. 158 1.2.2.2 thorpej */ 159 1.2.2.2 thorpej int 160 1.2.2.2 thorpej dmover_backend_alloc(struct dmover_session *dses, const char *type) 161 1.2.2.2 thorpej { 162 1.2.2.2 thorpej struct dmover_backend *dmb, *best_dmb = NULL; 163 1.2.2.2 thorpej const struct dmover_algdesc *algdesc, *best_algdesc = NULL; 164 1.2.2.2 thorpej 165 1.2.2.2 thorpej if (__predict_false(initialized == 0)) { 166 1.2.2.2 thorpej int fail; 167 1.2.2.2 thorpej 168 1.2.2.2 thorpej simple_lock(&initialized_slock); 169 1.2.2.2 thorpej fail = (initialized == 0); 170 1.2.2.2 thorpej simple_unlock(&initialized_slock); 171 1.2.2.2 thorpej 172 1.2.2.2 thorpej if (fail) 173 1.2.2.2 thorpej return (ESRCH); 174 1.2.2.2 thorpej } 175 1.2.2.2 thorpej 176 1.2.2.2 thorpej BACKEND_LIST_LOCK_READ(); 177 1.2.2.2 thorpej 178 1.2.2.2 thorpej /* First, find a back-end that can handle the session parts. */ 179 1.2.2.2 thorpej for (dmb = TAILQ_FIRST(&dmover_backend_list); dmb != NULL; 180 1.2.2.2 thorpej dmb = TAILQ_NEXT(dmb, dmb_list)) { 181 1.2.2.2 thorpej /* 182 1.2.2.2 thorpej * First, check to see if the back-end supports the 183 1.2.2.2 thorpej * function we wish to perform. 184 1.2.2.2 thorpej */ 185 1.2.2.2 thorpej algdesc = dmover_algdesc_lookup(dmb->dmb_algdescs, 186 1.2.2.2 thorpej dmb->dmb_nalgdescs, type); 187 1.2.2.2 thorpej if (algdesc == NULL) 188 1.2.2.2 thorpej continue; 189 1.2.2.2 thorpej 190 1.2.2.2 thorpej if (best_dmb == NULL) { 191 1.2.2.2 thorpej best_dmb = dmb; 192 1.2.2.2 thorpej best_algdesc = algdesc; 193 1.2.2.2 thorpej continue; 194 1.2.2.2 thorpej } 195 1.2.2.2 thorpej 196 1.2.2.2 thorpej /* 197 1.2.2.2 thorpej * XXX All the stuff from here on should be shot in 198 1.2.2.2 thorpej * XXX the head. Instead, we should build a list 199 1.2.2.2 thorpej * XXX of candidates, and select the best back-end 200 1.2.2.2 thorpej * XXX when a request is scheduled for processing. 201 1.2.2.2 thorpej */ 202 1.2.2.2 thorpej 203 1.2.2.2 thorpej if (dmb->dmb_speed >= best_dmb->dmb_speed) { 204 1.2.2.2 thorpej /* 205 1.2.2.2 thorpej * If the current best match is slower than 206 1.2.2.2 thorpej * this back-end, then this one is the new 207 1.2.2.2 thorpej * best match. 208 1.2.2.2 thorpej */ 209 1.2.2.2 thorpej if (dmb->dmb_speed > best_dmb->dmb_speed) { 210 1.2.2.2 thorpej best_dmb = dmb; 211 1.2.2.2 thorpej best_algdesc = algdesc; 212 1.2.2.2 thorpej continue; 213 1.2.2.2 thorpej } 214 1.2.2.2 thorpej 215 1.2.2.2 thorpej /* 216 1.2.2.2 thorpej * If this back-end has fewer sessions allocated 217 1.2.2.2 thorpej * to it than the current best match, then this 218 1.2.2.2 thorpej * one is now the best match. 219 1.2.2.2 thorpej */ 220 1.2.2.2 thorpej if (best_dmb->dmb_nsessions > dmb->dmb_nsessions) { 221 1.2.2.2 thorpej best_dmb = dmb; 222 1.2.2.2 thorpej best_algdesc = algdesc; 223 1.2.2.2 thorpej continue; 224 1.2.2.2 thorpej } 225 1.2.2.2 thorpej } 226 1.2.2.2 thorpej } 227 1.2.2.2 thorpej if (best_dmb == NULL) { 228 1.2.2.2 thorpej BACKEND_LIST_UNLOCK_READ(); 229 1.2.2.2 thorpej return (ESRCH); 230 1.2.2.2 thorpej } 231 1.2.2.2 thorpej 232 1.2.2.2 thorpej KASSERT(best_algdesc != NULL); 233 1.2.2.2 thorpej 234 1.2.2.2 thorpej /* Plug the back-end into the static (XXX) assignment. */ 235 1.2.2.2 thorpej dses->__dses_assignment.das_backend = best_dmb; 236 1.2.2.2 thorpej dses->__dses_assignment.das_algdesc = best_algdesc; 237 1.2.2.2 thorpej 238 1.2.2.2 thorpej dses->dses_ninputs = algdesc->dad_ninputs; 239 1.2.2.2 thorpej 240 1.2.2.2 thorpej LIST_INSERT_HEAD(&best_dmb->dmb_sessions, dses, __dses_list); 241 1.2.2.2 thorpej best_dmb->dmb_nsessions++; 242 1.2.2.2 thorpej 243 1.2.2.2 thorpej BACKEND_LIST_UNLOCK_READ(); 244 1.2.2.2 thorpej 245 1.2.2.2 thorpej return (0); 246 1.2.2.2 thorpej } 247 1.2.2.2 thorpej 248 1.2.2.2 thorpej /* 249 1.2.2.2 thorpej * dmover_backend_release: 250 1.2.2.2 thorpej * 251 1.2.2.2 thorpej * Release the back-end from the specified session. 252 1.2.2.2 thorpej */ 253 1.2.2.2 thorpej void 254 1.2.2.2 thorpej dmover_backend_release(struct dmover_session *dses) 255 1.2.2.2 thorpej { 256 1.2.2.2 thorpej struct dmover_backend *dmb; 257 1.2.2.2 thorpej 258 1.2.2.2 thorpej BACKEND_LIST_UNLOCK_READ(); 259 1.2.2.2 thorpej 260 1.2.2.2 thorpej /* XXX Clear out the static assignment. */ 261 1.2.2.2 thorpej dmb = dses->__dses_assignment.das_backend; 262 1.2.2.2 thorpej dses->__dses_assignment.das_backend = NULL; 263 1.2.2.2 thorpej dses->__dses_assignment.das_algdesc = NULL; 264 1.2.2.2 thorpej 265 1.2.2.2 thorpej LIST_REMOVE(dses, __dses_list); 266 1.2.2.2 thorpej dmb->dmb_nsessions--; 267 1.2.2.2 thorpej 268 1.2.2.2 thorpej BACKEND_LIST_UNLOCK_READ(); 269 1.2.2.2 thorpej } 270
Indexes created Thu Oct 02 10:09:58 GMT 2025