1 /*- 2 * Copyright (c) 2012 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Edward Tomasz Napierala under sponsorship 6 * from the FreeBSD Foundation. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 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 the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 */ 30 31 /* 32 * iSCSI Common Layer. It's used by both the initiator and target to send 33 * and receive iSCSI PDUs. 34 */ 35 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 39 #include <sys/param.h> 40 #include <sys/condvar.h> 41 #include <sys/conf.h> 42 #include <sys/lock.h> 43 #include <sys/kernel.h> 44 #include <sys/malloc.h> 45 #include <sys/mutex.h> 46 #include <sys/module.h> 47 #include <sys/queue.h> 48 #include <sys/sbuf.h> 49 #include <sys/socket.h> 50 #include <sys/sysctl.h> 51 #include <sys/systm.h> 52 #include <sys/sx.h> 53 54 #include <dev/iscsi/icl.h> 55 #include <icl_conn_if.h> 56 57 struct icl_module { 58 TAILQ_ENTRY(icl_module) im_next; 59 char *im_name; 60 bool im_iser; 61 int im_priority; 62 int (*im_limits)(size_t *limitp); 63 struct icl_conn *(*im_new_conn)(const char *name, 64 struct mtx *lock); 65 }; 66 67 struct icl_softc { 68 struct sx sc_lock; 69 TAILQ_HEAD(, icl_module) sc_modules; 70 }; 71 72 static int sysctl_kern_icl_offloads(SYSCTL_HANDLER_ARGS); 73 static MALLOC_DEFINE(M_ICL, "icl", "iSCSI Common Layer"); 74 static struct icl_softc *sc; 75 76 SYSCTL_NODE(_kern, OID_AUTO, icl, CTLFLAG_RD, 0, "iSCSI Common Layer"); 77 int icl_debug = 1; 78 SYSCTL_INT(_kern_icl, OID_AUTO, debug, CTLFLAG_RWTUN, 79 &icl_debug, 0, "Enable debug messages"); 80 SYSCTL_PROC(_kern_icl, OID_AUTO, offloads, 81 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 82 NULL, false, sysctl_kern_icl_offloads, "A", 83 "List of ICL modules"); 84 SYSCTL_PROC(_kern_icl, OID_AUTO, iser_offloads, 85 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 86 NULL, true, sysctl_kern_icl_offloads, "A", 87 "List of iSER ICL modules"); 88 89 static int 90 sysctl_kern_icl_offloads(SYSCTL_HANDLER_ARGS) 91 { 92 const struct icl_module *im; 93 struct sbuf sb; 94 bool iser = arg2; 95 int error; 96 97 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); 98 99 sx_slock(&sc->sc_lock); 100 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 101 if (im->im_iser != iser) 102 continue; 103 if (im != TAILQ_FIRST(&sc->sc_modules)) 104 sbuf_putc(&sb, ' '); 105 sbuf_printf(&sb, "%s", im->im_name); 106 } 107 sx_sunlock(&sc->sc_lock); 108 109 error = sbuf_finish(&sb); 110 if (error == 0) 111 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 112 sbuf_delete(&sb); 113 return (error); 114 } 115 116 static struct icl_module * 117 icl_find(const char *name, bool iser, bool quiet) 118 { 119 struct icl_module *im, *im_max; 120 121 sx_assert(&sc->sc_lock, SA_LOCKED); 122 123 /* 124 * If the name was not specified, pick a module with highest 125 * priority. 126 */ 127 if (name == NULL || name[0] == '\0') { 128 im_max = NULL; 129 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 130 if (im->im_iser != iser) 131 continue; 132 if (im_max == NULL || 133 im->im_priority > im_max->im_priority) 134 im_max = im; 135 } 136 137 if (iser && im_max == NULL && !quiet) 138 ICL_WARN("no iSER-capable offload found"); 139 140 return (im_max); 141 } 142 143 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 144 if (strcasecmp(im->im_name, name) != 0) 145 continue; 146 147 if (!im->im_iser && iser && !quiet) { 148 ICL_WARN("offload \"%s\" is not iSER-capable", name); 149 return (NULL); 150 } 151 if (im->im_iser && !iser && !quiet) { 152 ICL_WARN("offload \"%s\" is iSER-only", name); 153 return (NULL); 154 } 155 156 return (im); 157 } 158 159 if (!quiet) 160 ICL_WARN("offload \"%s\" not found", name); 161 162 return (NULL); 163 } 164 165 struct icl_conn * 166 icl_new_conn(const char *offload, bool iser, const char *name, struct mtx *lock) 167 { 168 struct icl_module *im; 169 struct icl_conn *ic; 170 171 sx_slock(&sc->sc_lock); 172 im = icl_find(offload, iser, false); 173 if (im == NULL) { 174 sx_sunlock(&sc->sc_lock); 175 return (NULL); 176 } 177 178 ic = im->im_new_conn(name, lock); 179 sx_sunlock(&sc->sc_lock); 180 181 return (ic); 182 } 183 184 int 185 icl_limits(const char *offload, bool iser, size_t *limitp) 186 { 187 struct icl_module *im; 188 int error; 189 190 sx_slock(&sc->sc_lock); 191 im = icl_find(offload, iser, false); 192 if (im == NULL) { 193 sx_sunlock(&sc->sc_lock); 194 return (ENXIO); 195 } 196 197 error = im->im_limits(limitp); 198 sx_sunlock(&sc->sc_lock); 199 200 return (error); 201 } 202 203 int 204 icl_register(const char *offload, bool iser, int priority, int (*limits)(size_t *), 205 struct icl_conn *(*new_conn)(const char *, struct mtx *)) 206 { 207 struct icl_module *im; 208 209 sx_xlock(&sc->sc_lock); 210 im = icl_find(offload, iser, true); 211 if (im != NULL) { 212 ICL_WARN("offload \"%s\" already registered", offload); 213 sx_xunlock(&sc->sc_lock); 214 return (EBUSY); 215 } 216 217 im = malloc(sizeof(*im), M_ICL, M_ZERO | M_WAITOK); 218 im->im_name = strdup(offload, M_ICL); 219 im->im_iser = iser; 220 im->im_priority = priority; 221 im->im_limits = limits; 222 im->im_new_conn = new_conn; 223 224 TAILQ_INSERT_HEAD(&sc->sc_modules, im, im_next); 225 sx_xunlock(&sc->sc_lock); 226 227 ICL_DEBUG("offload \"%s\" registered", offload); 228 return (0); 229 } 230 231 int 232 icl_unregister(const char *offload, bool rdma) 233 { 234 struct icl_module *im; 235 236 sx_xlock(&sc->sc_lock); 237 im = icl_find(offload, rdma, true); 238 if (im == NULL) { 239 ICL_WARN("offload \"%s\" not registered", offload); 240 sx_xunlock(&sc->sc_lock); 241 return (ENXIO); 242 } 243 244 TAILQ_REMOVE(&sc->sc_modules, im, im_next); 245 sx_xunlock(&sc->sc_lock); 246 247 free(im->im_name, M_ICL); 248 free(im, M_ICL); 249 250 ICL_DEBUG("offload \"%s\" unregistered", offload); 251 return (0); 252 } 253 254 static int 255 icl_load(void) 256 { 257 258 sc = malloc(sizeof(*sc), M_ICL, M_ZERO | M_WAITOK); 259 sx_init(&sc->sc_lock, "icl"); 260 TAILQ_INIT(&sc->sc_modules); 261 262 return (0); 263 } 264 265 static int 266 icl_unload(void) 267 { 268 269 sx_slock(&sc->sc_lock); 270 KASSERT(TAILQ_EMPTY(&sc->sc_modules), ("still have modules")); 271 sx_sunlock(&sc->sc_lock); 272 273 sx_destroy(&sc->sc_lock); 274 free(sc, M_ICL); 275 276 return (0); 277 } 278 279 static int 280 icl_modevent(module_t mod, int what, void *arg) 281 { 282 283 switch (what) { 284 case MOD_LOAD: 285 return (icl_load()); 286 case MOD_UNLOAD: 287 return (icl_unload()); 288 default: 289 return (EINVAL); 290 } 291 } 292 293 moduledata_t icl_data = { 294 "icl", 295 icl_modevent, 296 0 297 }; 298 299 DECLARE_MODULE(icl, icl_data, SI_SUB_DRIVERS, SI_ORDER_FIRST); 300 MODULE_VERSION(icl, 1); 301