1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2012 The FreeBSD Foundation 5 * All rights reserved. 6 * 7 * This software was developed by Edward Tomasz Napierala under sponsorship 8 * from the FreeBSD Foundation. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 */ 32 33 /* 34 * iSCSI Common Layer. It's used by both the initiator and target to send 35 * and receive iSCSI PDUs. 36 */ 37 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include <sys/param.h> 42 #include <sys/condvar.h> 43 #include <sys/conf.h> 44 #include <sys/lock.h> 45 #include <sys/kernel.h> 46 #include <sys/malloc.h> 47 #include <sys/mutex.h> 48 #include <sys/module.h> 49 #include <sys/queue.h> 50 #include <sys/sbuf.h> 51 #include <sys/socket.h> 52 #include <sys/sysctl.h> 53 #include <sys/systm.h> 54 #include <sys/sx.h> 55 56 #include <dev/iscsi/icl.h> 57 #include <icl_conn_if.h> 58 59 struct icl_module { 60 TAILQ_ENTRY(icl_module) im_next; 61 char *im_name; 62 bool im_iser; 63 int im_priority; 64 int (*im_limits)(struct icl_drv_limits *idl); 65 struct icl_conn *(*im_new_conn)(const char *name, 66 struct mtx *lock); 67 }; 68 69 struct icl_softc { 70 struct sx sc_lock; 71 TAILQ_HEAD(, icl_module) sc_modules; 72 }; 73 74 static int sysctl_kern_icl_offloads(SYSCTL_HANDLER_ARGS); 75 static MALLOC_DEFINE(M_ICL, "icl", "iSCSI Common Layer"); 76 static struct icl_softc *sc; 77 78 SYSCTL_NODE(_kern, OID_AUTO, icl, CTLFLAG_RD, 0, "iSCSI Common Layer"); 79 int icl_debug = 1; 80 SYSCTL_INT(_kern_icl, OID_AUTO, debug, CTLFLAG_RWTUN, 81 &icl_debug, 0, "Enable debug messages"); 82 SYSCTL_PROC(_kern_icl, OID_AUTO, offloads, 83 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 84 NULL, false, sysctl_kern_icl_offloads, "A", 85 "List of ICL modules"); 86 SYSCTL_PROC(_kern_icl, OID_AUTO, iser_offloads, 87 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 88 NULL, true, sysctl_kern_icl_offloads, "A", 89 "List of iSER ICL modules"); 90 91 static int 92 sysctl_kern_icl_offloads(SYSCTL_HANDLER_ARGS) 93 { 94 const struct icl_module *im; 95 struct sbuf sb; 96 bool iser = arg2; 97 int error; 98 99 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); 100 101 sx_slock(&sc->sc_lock); 102 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 103 if (im->im_iser != iser) 104 continue; 105 if (im != TAILQ_FIRST(&sc->sc_modules)) 106 sbuf_putc(&sb, ' '); 107 sbuf_printf(&sb, "%s", im->im_name); 108 } 109 sx_sunlock(&sc->sc_lock); 110 111 error = sbuf_finish(&sb); 112 if (error == 0) 113 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 114 sbuf_delete(&sb); 115 return (error); 116 } 117 118 static struct icl_module * 119 icl_find(const char *name, bool iser, bool quiet) 120 { 121 struct icl_module *im, *im_max; 122 123 sx_assert(&sc->sc_lock, SA_LOCKED); 124 125 /* 126 * If the name was not specified, pick a module with highest 127 * priority. 128 */ 129 if (name == NULL || name[0] == '\0') { 130 im_max = NULL; 131 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 132 if (im->im_iser != iser) 133 continue; 134 if (im_max == NULL || 135 im->im_priority > im_max->im_priority) 136 im_max = im; 137 } 138 139 if (iser && im_max == NULL && !quiet) 140 ICL_WARN("no iSER-capable offload found"); 141 142 return (im_max); 143 } 144 145 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 146 if (strcasecmp(im->im_name, name) != 0) 147 continue; 148 149 if (!im->im_iser && iser && !quiet) { 150 ICL_WARN("offload \"%s\" is not iSER-capable", name); 151 return (NULL); 152 } 153 if (im->im_iser && !iser && !quiet) { 154 ICL_WARN("offload \"%s\" is iSER-only", name); 155 return (NULL); 156 } 157 158 return (im); 159 } 160 161 if (!quiet) 162 ICL_WARN("offload \"%s\" not found", name); 163 164 return (NULL); 165 } 166 167 struct icl_conn * 168 icl_new_conn(const char *offload, bool iser, const char *name, struct mtx *lock) 169 { 170 struct icl_module *im; 171 struct icl_conn *ic; 172 173 sx_slock(&sc->sc_lock); 174 im = icl_find(offload, iser, false); 175 if (im == NULL) { 176 sx_sunlock(&sc->sc_lock); 177 return (NULL); 178 } 179 180 ic = im->im_new_conn(name, lock); 181 sx_sunlock(&sc->sc_lock); 182 183 return (ic); 184 } 185 186 int 187 icl_limits(const char *offload, bool iser, struct icl_drv_limits *idl) 188 { 189 struct icl_module *im; 190 int error; 191 192 bzero(idl, sizeof(*idl)); 193 sx_slock(&sc->sc_lock); 194 im = icl_find(offload, iser, false); 195 if (im == NULL) { 196 sx_sunlock(&sc->sc_lock); 197 return (ENXIO); 198 } 199 200 error = im->im_limits(idl); 201 sx_sunlock(&sc->sc_lock); 202 203 /* 204 * Validate the limits provided by the driver against values allowed by 205 * the iSCSI RFC. 0 means iscsid/ctld should pick a reasonable value. 206 * 207 * Note that max_send_dsl is an internal implementation detail and not 208 * part of the RFC. 209 */ 210 #define OUT_OF_RANGE(x, lo, hi) ((x) != 0 && ((x) < (lo) || (x) > (hi))) 211 if (error == 0 && 212 (OUT_OF_RANGE(idl->idl_max_recv_data_segment_length, 512, 16777215) || 213 OUT_OF_RANGE(idl->idl_max_send_data_segment_length, 512, 16777215) || 214 OUT_OF_RANGE(idl->idl_max_burst_length, 512, 16777215) || 215 OUT_OF_RANGE(idl->idl_first_burst_length, 512, 16777215))) { 216 error = EINVAL; 217 } 218 #undef OUT_OF_RANGE 219 220 /* 221 * If both first_burst and max_burst are provided then first_burst must 222 * not exceed max_burst. 223 */ 224 if (error == 0 && idl->idl_first_burst_length > 0 && 225 idl->idl_max_burst_length > 0 && 226 idl->idl_first_burst_length > idl->idl_max_burst_length) { 227 error = EINVAL; 228 } 229 230 return (error); 231 } 232 233 int 234 icl_register(const char *offload, bool iser, int priority, 235 int (*limits)(struct icl_drv_limits *), 236 struct icl_conn *(*new_conn)(const char *, struct mtx *)) 237 { 238 struct icl_module *im; 239 240 sx_xlock(&sc->sc_lock); 241 im = icl_find(offload, iser, true); 242 if (im != NULL) { 243 ICL_WARN("offload \"%s\" already registered", offload); 244 sx_xunlock(&sc->sc_lock); 245 return (EBUSY); 246 } 247 248 im = malloc(sizeof(*im), M_ICL, M_ZERO | M_WAITOK); 249 im->im_name = strdup(offload, M_ICL); 250 im->im_iser = iser; 251 im->im_priority = priority; 252 im->im_limits = limits; 253 im->im_new_conn = new_conn; 254 255 TAILQ_INSERT_HEAD(&sc->sc_modules, im, im_next); 256 sx_xunlock(&sc->sc_lock); 257 258 ICL_DEBUG("offload \"%s\" registered", offload); 259 return (0); 260 } 261 262 int 263 icl_unregister(const char *offload, bool rdma) 264 { 265 struct icl_module *im; 266 267 sx_xlock(&sc->sc_lock); 268 im = icl_find(offload, rdma, true); 269 if (im == NULL) { 270 ICL_WARN("offload \"%s\" not registered", offload); 271 sx_xunlock(&sc->sc_lock); 272 return (ENXIO); 273 } 274 275 TAILQ_REMOVE(&sc->sc_modules, im, im_next); 276 sx_xunlock(&sc->sc_lock); 277 278 free(im->im_name, M_ICL); 279 free(im, M_ICL); 280 281 ICL_DEBUG("offload \"%s\" unregistered", offload); 282 return (0); 283 } 284 285 static int 286 icl_load(void) 287 { 288 289 sc = malloc(sizeof(*sc), M_ICL, M_ZERO | M_WAITOK); 290 sx_init(&sc->sc_lock, "icl"); 291 TAILQ_INIT(&sc->sc_modules); 292 293 return (0); 294 } 295 296 static int 297 icl_unload(void) 298 { 299 300 sx_slock(&sc->sc_lock); 301 KASSERT(TAILQ_EMPTY(&sc->sc_modules), ("still have modules")); 302 sx_sunlock(&sc->sc_lock); 303 304 sx_destroy(&sc->sc_lock); 305 free(sc, M_ICL); 306 307 return (0); 308 } 309 310 static int 311 icl_modevent(module_t mod, int what, void *arg) 312 { 313 314 switch (what) { 315 case MOD_LOAD: 316 return (icl_load()); 317 case MOD_UNLOAD: 318 return (icl_unload()); 319 default: 320 return (EINVAL); 321 } 322 } 323 324 moduledata_t icl_data = { 325 "icl", 326 icl_modevent, 327 0 328 }; 329 330 DECLARE_MODULE(icl, icl_data, SI_SUB_DRIVERS, SI_ORDER_FIRST); 331 MODULE_VERSION(icl, 1); 332