1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2012 The FreeBSD Foundation 5 * 6 * This software was developed by Edward Tomasz Napierala under sponsorship 7 * from the FreeBSD Foundation. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 */ 31 32 /* 33 * iSCSI Common Layer. It's used by both the initiator and target to send 34 * and receive iSCSI PDUs. 35 */ 36 37 #include <sys/param.h> 38 #include <sys/condvar.h> 39 #include <sys/conf.h> 40 #include <sys/lock.h> 41 #include <sys/kernel.h> 42 #include <sys/malloc.h> 43 #include <sys/mutex.h> 44 #include <sys/module.h> 45 #include <sys/queue.h> 46 #include <sys/sbuf.h> 47 #include <sys/socket.h> 48 #include <sys/sysctl.h> 49 #include <sys/systm.h> 50 #include <sys/sx.h> 51 52 #include <dev/iscsi/icl.h> 53 #include <icl_conn_if.h> 54 55 struct icl_module { 56 TAILQ_ENTRY(icl_module) im_next; 57 char *im_name; 58 bool im_iser; 59 int im_priority; 60 int (*im_limits)(struct icl_drv_limits *idl, 61 int socket); 62 struct icl_conn *(*im_new_conn)(const char *name, 63 struct mtx *lock); 64 }; 65 66 struct icl_softc { 67 struct sx sc_lock; 68 TAILQ_HEAD(, icl_module) sc_modules; 69 }; 70 71 static int sysctl_kern_icl_offloads(SYSCTL_HANDLER_ARGS); 72 static MALLOC_DEFINE(M_ICL, "icl", "iSCSI Common Layer"); 73 static struct icl_softc *sc; 74 75 SYSCTL_NODE(_kern, OID_AUTO, icl, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 76 "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, int socket, 186 struct icl_drv_limits *idl) 187 { 188 struct icl_module *im; 189 int error; 190 191 bzero(idl, sizeof(*idl)); 192 sx_slock(&sc->sc_lock); 193 im = icl_find(offload, iser, false); 194 if (im == NULL) { 195 sx_sunlock(&sc->sc_lock); 196 return (ENXIO); 197 } 198 199 error = im->im_limits(idl, socket); 200 sx_sunlock(&sc->sc_lock); 201 202 /* 203 * Validate the limits provided by the driver against values allowed by 204 * the iSCSI RFC. 0 means iscsid/ctld should pick a reasonable value. 205 * 206 * Note that max_send_dsl is an internal implementation detail and not 207 * part of the RFC. 208 */ 209 #define OUT_OF_RANGE(x, lo, hi) ((x) != 0 && ((x) < (lo) || (x) > (hi))) 210 if (error == 0 && 211 (OUT_OF_RANGE(idl->idl_max_recv_data_segment_length, 512, 16777215) || 212 OUT_OF_RANGE(idl->idl_max_send_data_segment_length, 512, 16777215) || 213 OUT_OF_RANGE(idl->idl_max_burst_length, 512, 16777215) || 214 OUT_OF_RANGE(idl->idl_first_burst_length, 512, 16777215))) { 215 error = EINVAL; 216 } 217 #undef OUT_OF_RANGE 218 219 /* 220 * If both first_burst and max_burst are provided then first_burst must 221 * not exceed max_burst. 222 */ 223 if (error == 0 && idl->idl_first_burst_length > 0 && 224 idl->idl_max_burst_length > 0 && 225 idl->idl_first_burst_length > idl->idl_max_burst_length) { 226 error = EINVAL; 227 } 228 229 return (error); 230 } 231 232 int 233 icl_register(const char *offload, bool iser, int priority, 234 int (*limits)(struct icl_drv_limits *, int), 235 struct icl_conn *(*new_conn)(const char *, struct mtx *)) 236 { 237 struct icl_module *im; 238 239 sx_xlock(&sc->sc_lock); 240 im = icl_find(offload, iser, true); 241 if (im != NULL) { 242 ICL_WARN("offload \"%s\" already registered", offload); 243 sx_xunlock(&sc->sc_lock); 244 return (EBUSY); 245 } 246 247 im = malloc(sizeof(*im), M_ICL, M_ZERO | M_WAITOK); 248 im->im_name = strdup(offload, M_ICL); 249 im->im_iser = iser; 250 im->im_priority = priority; 251 im->im_limits = limits; 252 im->im_new_conn = new_conn; 253 254 TAILQ_INSERT_HEAD(&sc->sc_modules, im, im_next); 255 sx_xunlock(&sc->sc_lock); 256 257 ICL_DEBUG("offload \"%s\" registered", offload); 258 return (0); 259 } 260 261 int 262 icl_unregister(const char *offload, bool rdma) 263 { 264 struct icl_module *im; 265 266 sx_xlock(&sc->sc_lock); 267 im = icl_find(offload, rdma, true); 268 if (im == NULL) { 269 ICL_WARN("offload \"%s\" not registered", offload); 270 sx_xunlock(&sc->sc_lock); 271 return (ENXIO); 272 } 273 274 TAILQ_REMOVE(&sc->sc_modules, im, im_next); 275 sx_xunlock(&sc->sc_lock); 276 277 free(im->im_name, M_ICL); 278 free(im, M_ICL); 279 280 ICL_DEBUG("offload \"%s\" unregistered", offload); 281 return (0); 282 } 283 284 static int 285 icl_load(void) 286 { 287 288 sc = malloc(sizeof(*sc), M_ICL, M_ZERO | M_WAITOK); 289 sx_init(&sc->sc_lock, "icl"); 290 TAILQ_INIT(&sc->sc_modules); 291 292 return (0); 293 } 294 295 static int 296 icl_unload(void) 297 { 298 299 sx_slock(&sc->sc_lock); 300 KASSERT(TAILQ_EMPTY(&sc->sc_modules), ("still have modules")); 301 sx_sunlock(&sc->sc_lock); 302 303 sx_destroy(&sc->sc_lock); 304 free(sc, M_ICL); 305 306 return (0); 307 } 308 309 static int 310 icl_modevent(module_t mod, int what, void *arg) 311 { 312 313 switch (what) { 314 case MOD_LOAD: 315 return (icl_load()); 316 case MOD_UNLOAD: 317 return (icl_unload()); 318 default: 319 return (EINVAL); 320 } 321 } 322 323 moduledata_t icl_data = { 324 "icl", 325 icl_modevent, 326 0 327 }; 328 329 DECLARE_MODULE(icl, icl_data, SI_SUB_DRIVERS, SI_ORDER_FIRST); 330 MODULE_VERSION(icl, 1); 331