/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2012 The FreeBSD Foundation
*
* This software was developed by Edward Tomasz Napierala under sponsorship
* from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/*
* iSCSI Common Layer. It's used by both the initiator and target to send
* and receive iSCSI PDUs.
*/
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/condvar.h>
#include <sys/conf.h>
#include <sys/lock.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/module.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/sx.h>
#include <dev/iscsi/icl.h>
#include <icl_conn_if.h>
struct icl_module {
TAILQ_ENTRY(icl_module) im_next;
char *im_name;
bool im_iser;
int im_priority;
int (*im_limits)(struct icl_drv_limits *idl,
int socket);
struct icl_conn *(*im_new_conn)(const char *name,
struct mtx *lock);
};
struct icl_softc {
struct sx sc_lock;
TAILQ_HEAD(, icl_module) sc_modules;
};
static int sysctl_kern_icl_offloads(SYSCTL_HANDLER_ARGS);
static MALLOC_DEFINE(M_ICL, "icl", "iSCSI Common Layer");
static struct icl_softc *sc;
SYSCTL_NODE(_kern, OID_AUTO, icl, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
"iSCSI Common Layer");
int icl_debug = 1;
SYSCTL_INT(_kern_icl, OID_AUTO, debug, CTLFLAG_RWTUN,
&icl_debug, 0, "Enable debug messages");
SYSCTL_PROC(_kern_icl, OID_AUTO, offloads,
CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
NULL, false, sysctl_kern_icl_offloads, "A",
"List of ICL modules");
SYSCTL_PROC(_kern_icl, OID_AUTO, iser_offloads,
CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
NULL, true, sysctl_kern_icl_offloads, "A",
"List of iSER ICL modules");
static int
sysctl_kern_icl_offloads(SYSCTL_HANDLER_ARGS)
{
const struct icl_module *im;
struct sbuf sb;
bool iser = arg2;
int error;
sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL);
sx_slock(&sc->sc_lock);
TAILQ_FOREACH(im, &sc->sc_modules, im_next) {
if (im->im_iser != iser)
continue;
if (im != TAILQ_FIRST(&sc->sc_modules))
sbuf_putc(&sb, ' ');
sbuf_printf(&sb, "%s", im->im_name);
}
sx_sunlock(&sc->sc_lock);
error = sbuf_finish(&sb);
if (error == 0)
error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb));
sbuf_delete(&sb);
return (error);
}
static struct icl_module *
icl_find(const char *name, bool iser, bool quiet)
{
struct icl_module *im, *im_max;
sx_assert(&sc->sc_lock, SA_LOCKED);
/*
* If the name was not specified, pick a module with highest
* priority.
*/
if (name == NULL || name[0] == '\0') {
im_max = NULL;
TAILQ_FOREACH(im, &sc->sc_modules, im_next) {
if (im->im_iser != iser)
continue;
if (im_max == NULL ||
im->im_priority > im_max->im_priority)
im_max = im;
}
if (iser && im_max == NULL && !quiet)
ICL_WARN("no iSER-capable offload found");
return (im_max);
}
TAILQ_FOREACH(im, &sc->sc_modules, im_next) {
if (strcasecmp(im->im_name, name) != 0)
continue;
if (!im->im_iser && iser && !quiet) {
ICL_WARN("offload \"%s\" is not iSER-capable", name);
return (NULL);
}
if (im->im_iser && !iser && !quiet) {
ICL_WARN("offload \"%s\" is iSER-only", name);
return (NULL);
}
return (im);
}
if (!quiet)
ICL_WARN("offload \"%s\" not found", name);
return (NULL);
}
struct icl_conn *
icl_new_conn(const char *offload, bool iser, const char *name, struct mtx *lock)
{
struct icl_module *im;
struct icl_conn *ic;
sx_slock(&sc->sc_lock);
im = icl_find(offload, iser, false);
if (im == NULL) {
sx_sunlock(&sc->sc_lock);
return (NULL);
}
ic = im->im_new_conn(name, lock);
sx_sunlock(&sc->sc_lock);
return (ic);
}
int
icl_limits(const char *offload, bool iser, int socket,
struct icl_drv_limits *idl)
{
struct icl_module *im;
int error;
bzero(idl, sizeof(*idl));
sx_slock(&sc->sc_lock);
im = icl_find(offload, iser, false);
if (im == NULL) {
sx_sunlock(&sc->sc_lock);
return (ENXIO);
}
error = im->im_limits(idl, socket);
sx_sunlock(&sc->sc_lock);
/*
* Validate the limits provided by the driver against values allowed by
* the iSCSI RFC. 0 means iscsid/ctld should pick a reasonable value.
*
* Note that max_send_dsl is an internal implementation detail and not
* part of the RFC.
*/
#define OUT_OF_RANGE(x, lo, hi) ((x) != 0 && ((x) < (lo) || (x) > (hi)))
if (error == 0 &&
(OUT_OF_RANGE(idl->idl_max_recv_data_segment_length, 512, 16777215) ||
OUT_OF_RANGE(idl->idl_max_send_data_segment_length, 512, 16777215) ||
OUT_OF_RANGE(idl->idl_max_burst_length, 512, 16777215) ||
OUT_OF_RANGE(idl->idl_first_burst_length, 512, 16777215))) {
error = EINVAL;
}
#undef OUT_OF_RANGE
/*
* If both first_burst and max_burst are provided then first_burst must
* not exceed max_burst.
*/
if (error == 0 && idl->idl_first_burst_length > 0 &&
idl->idl_max_burst_length > 0 &&
idl->idl_first_burst_length > idl->idl_max_burst_length) {
error = EINVAL;
}
return (error);
}
int
icl_register(const char *offload, bool iser, int priority,
int (*limits)(struct icl_drv_limits *, int),
struct icl_conn *(*new_conn)(const char *, struct mtx *))
{
struct icl_module *im;
sx_xlock(&sc->sc_lock);
im = icl_find(offload, iser, true);
if (im != NULL) {
ICL_WARN("offload \"%s\" already registered", offload);
sx_xunlock(&sc->sc_lock);
return (EBUSY);
}
im = malloc(sizeof(*im), M_ICL, M_ZERO | M_WAITOK);
im->im_name = strdup(offload, M_ICL);
im->im_iser = iser;
im->im_priority = priority;
im->im_limits = limits;
im->im_new_conn = new_conn;
TAILQ_INSERT_HEAD(&sc->sc_modules, im, im_next);
sx_xunlock(&sc->sc_lock);
ICL_DEBUG("offload \"%s\" registered", offload);
return (0);
}
int
icl_unregister(const char *offload, bool rdma)
{
struct icl_module *im;
sx_xlock(&sc->sc_lock);
im = icl_find(offload, rdma, true);
if (im == NULL) {
ICL_WARN("offload \"%s\" not registered", offload);
sx_xunlock(&sc->sc_lock);
return (ENXIO);
}
TAILQ_REMOVE(&sc->sc_modules, im, im_next);
sx_xunlock(&sc->sc_lock);
free(im->im_name, M_ICL);
free(im, M_ICL);
ICL_DEBUG("offload \"%s\" unregistered", offload);
return (0);
}
static int
icl_load(void)
{
sc = malloc(sizeof(*sc), M_ICL, M_ZERO | M_WAITOK);
sx_init(&sc->sc_lock, "icl");
TAILQ_INIT(&sc->sc_modules);
return (0);
}
static int
icl_unload(void)
{
sx_slock(&sc->sc_lock);
KASSERT(TAILQ_EMPTY(&sc->sc_modules), ("still have modules"));
sx_sunlock(&sc->sc_lock);
sx_destroy(&sc->sc_lock);
free(sc, M_ICL);
return (0);
}
static int
icl_modevent(module_t mod, int what, void *arg)
{
switch (what) {
case MOD_LOAD:
return (icl_load());
case MOD_UNLOAD:
return (icl_unload());
default:
return (EINVAL);
}
}
moduledata_t icl_data = {
"icl",
icl_modevent,
0
};
DECLARE_MODULE(icl, icl_data, SI_SUB_DRIVERS, SI_ORDER_FIRST);
MODULE_VERSION(icl, 1);
