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/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/condvar.h> 42 #include <sys/conf.h> 43 #include <sys/lock.h> 44 #include <sys/kernel.h> 45 #include <sys/malloc.h> 46 #include <sys/mutex.h> 47 #include <sys/module.h> 48 #include <sys/queue.h> 49 #include <sys/sbuf.h> 50 #include <sys/socket.h> 51 #include <sys/sysctl.h> 52 #include <sys/systm.h> 53 #include <sys/sx.h> 54 55 #include <dev/iscsi/icl.h> 56 #include <icl_conn_if.h> 57 58 struct icl_module { 59 TAILQ_ENTRY(icl_module) im_next; 60 char *im_name; 61 bool im_iser; 62 int im_priority; 63 int (*im_limits)(struct icl_drv_limits *idl, 64 int socket); 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 | CTLFLAG_MPSAFE, 0, 79 "iSCSI Common Layer"); 80 int icl_debug = 1; 81 SYSCTL_INT(_kern_icl, OID_AUTO, debug, CTLFLAG_RWTUN, 82 &icl_debug, 0, "Enable debug messages"); 83 SYSCTL_PROC(_kern_icl, OID_AUTO, offloads, 84 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 85 NULL, false, sysctl_kern_icl_offloads, "A", 86 "List of ICL modules"); 87 SYSCTL_PROC(_kern_icl, OID_AUTO, iser_offloads, 88 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 89 NULL, true, sysctl_kern_icl_offloads, "A", 90 "List of iSER ICL modules"); 91 92 static int 93 sysctl_kern_icl_offloads(SYSCTL_HANDLER_ARGS) 94 { 95 const struct icl_module *im; 96 struct sbuf sb; 97 bool iser = arg2; 98 int error; 99 100 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL); 101 102 sx_slock(&sc->sc_lock); 103 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 104 if (im->im_iser != iser) 105 continue; 106 if (im != TAILQ_FIRST(&sc->sc_modules)) 107 sbuf_putc(&sb, ' '); 108 sbuf_printf(&sb, "%s", im->im_name); 109 } 110 sx_sunlock(&sc->sc_lock); 111 112 error = sbuf_finish(&sb); 113 if (error == 0) 114 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb)); 115 sbuf_delete(&sb); 116 return (error); 117 } 118 119 static struct icl_module * 120 icl_find(const char *name, bool iser, bool quiet) 121 { 122 struct icl_module *im, *im_max; 123 124 sx_assert(&sc->sc_lock, SA_LOCKED); 125 126 /* 127 * If the name was not specified, pick a module with highest 128 * priority. 129 */ 130 if (name == NULL || name[0] == '\0') { 131 im_max = NULL; 132 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 133 if (im->im_iser != iser) 134 continue; 135 if (im_max == NULL || 136 im->im_priority > im_max->im_priority) 137 im_max = im; 138 } 139 140 if (iser && im_max == NULL && !quiet) 141 ICL_WARN("no iSER-capable offload found"); 142 143 return (im_max); 144 } 145 146 TAILQ_FOREACH(im, &sc->sc_modules, im_next) { 147 if (strcasecmp(im->im_name, name) != 0) 148 continue; 149 150 if (!im->im_iser && iser && !quiet) { 151 ICL_WARN("offload \"%s\" is not iSER-capable", name); 152 return (NULL); 153 } 154 if (im->im_iser && !iser && !quiet) { 155 ICL_WARN("offload \"%s\" is iSER-only", name); 156 return (NULL); 157 } 158 159 return (im); 160 } 161 162 if (!quiet) 163 ICL_WARN("offload \"%s\" not found", name); 164 165 return (NULL); 166 } 167 168 struct icl_conn * 169 icl_new_conn(const char *offload, bool iser, const char *name, struct mtx *lock) 170 { 171 struct icl_module *im; 172 struct icl_conn *ic; 173 174 sx_slock(&sc->sc_lock); 175 im = icl_find(offload, iser, false); 176 if (im == NULL) { 177 sx_sunlock(&sc->sc_lock); 178 return (NULL); 179 } 180 181 ic = im->im_new_conn(name, lock); 182 sx_sunlock(&sc->sc_lock); 183 184 return (ic); 185 } 186 187 int 188 icl_limits(const char *offload, bool iser, int socket, 189 struct icl_drv_limits *idl) 190 { 191 struct icl_module *im; 192 int error; 193 194 bzero(idl, sizeof(*idl)); 195 sx_slock(&sc->sc_lock); 196 im = icl_find(offload, iser, false); 197 if (im == NULL) { 198 sx_sunlock(&sc->sc_lock); 199 return (ENXIO); 200 } 201 202 error = im->im_limits(idl, socket); 203 sx_sunlock(&sc->sc_lock); 204 205 /* 206 * Validate the limits provided by the driver against values allowed by 207 * the iSCSI RFC. 0 means iscsid/ctld should pick a reasonable value. 208 * 209 * Note that max_send_dsl is an internal implementation detail and not 210 * part of the RFC. 211 */ 212 #define OUT_OF_RANGE(x, lo, hi) ((x) != 0 && ((x) < (lo) || (x) > (hi))) 213 if (error == 0 && 214 (OUT_OF_RANGE(idl->idl_max_recv_data_segment_length, 512, 16777215) || 215 OUT_OF_RANGE(idl->idl_max_send_data_segment_length, 512, 16777215) || 216 OUT_OF_RANGE(idl->idl_max_burst_length, 512, 16777215) || 217 OUT_OF_RANGE(idl->idl_first_burst_length, 512, 16777215))) { 218 error = EINVAL; 219 } 220 #undef OUT_OF_RANGE 221 222 /* 223 * If both first_burst and max_burst are provided then first_burst must 224 * not exceed max_burst. 225 */ 226 if (error == 0 && idl->idl_first_burst_length > 0 && 227 idl->idl_max_burst_length > 0 && 228 idl->idl_first_burst_length > idl->idl_max_burst_length) { 229 error = EINVAL; 230 } 231 232 return (error); 233 } 234 235 int 236 icl_register(const char *offload, bool iser, int priority, 237 int (*limits)(struct icl_drv_limits *, int), 238 struct icl_conn *(*new_conn)(const char *, struct mtx *)) 239 { 240 struct icl_module *im; 241 242 sx_xlock(&sc->sc_lock); 243 im = icl_find(offload, iser, true); 244 if (im != NULL) { 245 ICL_WARN("offload \"%s\" already registered", offload); 246 sx_xunlock(&sc->sc_lock); 247 return (EBUSY); 248 } 249 250 im = malloc(sizeof(*im), M_ICL, M_ZERO | M_WAITOK); 251 im->im_name = strdup(offload, M_ICL); 252 im->im_iser = iser; 253 im->im_priority = priority; 254 im->im_limits = limits; 255 im->im_new_conn = new_conn; 256 257 TAILQ_INSERT_HEAD(&sc->sc_modules, im, im_next); 258 sx_xunlock(&sc->sc_lock); 259 260 ICL_DEBUG("offload \"%s\" registered", offload); 261 return (0); 262 } 263 264 int 265 icl_unregister(const char *offload, bool rdma) 266 { 267 struct icl_module *im; 268 269 sx_xlock(&sc->sc_lock); 270 im = icl_find(offload, rdma, true); 271 if (im == NULL) { 272 ICL_WARN("offload \"%s\" not registered", offload); 273 sx_xunlock(&sc->sc_lock); 274 return (ENXIO); 275 } 276 277 TAILQ_REMOVE(&sc->sc_modules, im, im_next); 278 sx_xunlock(&sc->sc_lock); 279 280 free(im->im_name, M_ICL); 281 free(im, M_ICL); 282 283 ICL_DEBUG("offload \"%s\" unregistered", offload); 284 return (0); 285 } 286 287 static int 288 icl_load(void) 289 { 290 291 sc = malloc(sizeof(*sc), M_ICL, M_ZERO | M_WAITOK); 292 sx_init(&sc->sc_lock, "icl"); 293 TAILQ_INIT(&sc->sc_modules); 294 295 return (0); 296 } 297 298 static int 299 icl_unload(void) 300 { 301 302 sx_slock(&sc->sc_lock); 303 KASSERT(TAILQ_EMPTY(&sc->sc_modules), ("still have modules")); 304 sx_sunlock(&sc->sc_lock); 305 306 sx_destroy(&sc->sc_lock); 307 free(sc, M_ICL); 308 309 return (0); 310 } 311 312 static int 313 icl_modevent(module_t mod, int what, void *arg) 314 { 315 316 switch (what) { 317 case MOD_LOAD: 318 return (icl_load()); 319 case MOD_UNLOAD: 320 return (icl_unload()); 321 default: 322 return (EINVAL); 323 } 324 } 325 326 moduledata_t icl_data = { 327 "icl", 328 icl_modevent, 329 0 330 }; 331 332 DECLARE_MODULE(icl, icl_data, SI_SUB_DRIVERS, SI_ORDER_FIRST); 333 MODULE_VERSION(icl, 1); 334