/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved.
 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * a) Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 *
 * b) 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.
 *
 * c) Neither the name of Cisco Systems, Inc. nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
 */

#ifndef _NETINET_SCTP_LOCK_BSD_H_
#define _NETINET_SCTP_LOCK_BSD_H_

/*
 * General locking concepts: The goal of our locking is to of course provide
 * consistency and yet minimize overhead. We will attempt to use
 * non-recursive locks which are supposed to be quite inexpensive. Now in
 * order to do this the goal is that most functions are not aware of locking.
 * Once we have a TCB we lock it and unlock when we are through. This means
 * that the TCB lock is kind-of a "global" lock when working on an
 * association. Caution must be used when asserting a TCB_LOCK since if we
 * recurse we deadlock.
 *
 * Most other locks (INP and INFO) attempt to localize the locking i.e. we try
 * to contain the lock and unlock within the function that needs to lock it.
 * This sometimes mean we do extra locks and unlocks and lose a bit of
 * efficiency, but if the performance statements about non-recursive locks are
 * true this should not be a problem.  One issue that arises with this only
 * lock when needed is that if an implicit association setup is done we have
 * a problem. If at the time I lookup an association I have NULL in the tcb
 * return, by the time I call to create the association some other processor
 * could have created it. This is what the CREATE lock on the endpoint.
 * Places where we will be implicitly creating the association OR just
 * creating an association (the connect call) will assert the CREATE_INP
 * lock. This will assure us that during all the lookup of INP and INFO if
 * another creator is also locking/looking up we can gate the two to
 * synchronize. So the CREATE_INP lock is also another one we must use
 * extreme caution in locking to make sure we don't hit a re-entrancy issue.
 *
 */

/*
 * When working with the global SCTP lists we lock and unlock the INP_INFO
 * lock. So when we go to lookup an association we will want to do a
 * SCTP_INP_INFO_RLOCK() and then when we want to add a new association to
 * the SCTP_BASE_INFO() list's we will do a SCTP_INP_INFO_WLOCK().
 */

#define SCTP_IPI_COUNT_INIT()

#define SCTP_STATLOG_INIT_LOCK()
#define SCTP_STATLOG_DESTROY()
#define SCTP_STATLOG_LOCK()
#define SCTP_STATLOG_UNLOCK()

#define SCTP_INP_INFO_LOCK_INIT() do {                                  \
        rw_init(&SCTP_BASE_INFO(ipi_ep_mtx), "sctp-info");              \
} while (0)

#define SCTP_INP_INFO_LOCK_DESTROY() do {                               \
        if (rw_wowned(&SCTP_BASE_INFO(ipi_ep_mtx))) {                   \
                rw_wunlock(&SCTP_BASE_INFO(ipi_ep_mtx));                \
        }                                                               \
        rw_destroy(&SCTP_BASE_INFO(ipi_ep_mtx));                        \
} while (0)

#define SCTP_INP_INFO_RLOCK() do {                                      \
        rw_rlock(&SCTP_BASE_INFO(ipi_ep_mtx));                          \
} while (0)

#define SCTP_INP_INFO_WLOCK() do {                                      \
        rw_wlock(&SCTP_BASE_INFO(ipi_ep_mtx));                          \
} while (0)

#define SCTP_INP_INFO_RUNLOCK() do {                                    \
        rw_runlock(&SCTP_BASE_INFO(ipi_ep_mtx));                        \
} while (0)

#define SCTP_INP_INFO_WUNLOCK() do {                                    \
        rw_wunlock(&SCTP_BASE_INFO(ipi_ep_mtx));                        \
} while (0)

#define SCTP_INP_INFO_LOCK_ASSERT() do {                                \
        rw_assert(&SCTP_BASE_INFO(ipi_ep_mtx), RA_LOCKED);              \
} while (0)

#define SCTP_INP_INFO_RLOCK_ASSERT() do {                               \
        rw_assert(&SCTP_BASE_INFO(ipi_ep_mtx), RA_RLOCKED);             \
} while (0)

#define SCTP_INP_INFO_WLOCK_ASSERT() do {                               \
        rw_assert(&SCTP_BASE_INFO(ipi_ep_mtx), RA_WLOCKED);             \
} while (0)

#define SCTP_MCORE_QLOCK_INIT(cpstr) do {                               \
        mtx_init(&(cpstr)->que_mtx, "sctp-mcore_queue","queue_lock",    \
                 MTX_DEF | MTX_DUPOK);                                  \
} while (0)

#define SCTP_MCORE_QDESTROY(cpstr) do {                                 \
        if (mtx_owned(&(cpstr)->core_mtx)) {                            \
                mtx_unlock(&(cpstr)->que_mtx);                          \
        }                                                               \
        mtx_destroy(&(cpstr)->que_mtx);                                 \
} while (0)

#define SCTP_MCORE_QLOCK(cpstr) do {                                    \
        mtx_lock(&(cpstr)->que_mtx);                                    \
} while (0)

#define SCTP_MCORE_QUNLOCK(cpstr) do {                                  \
        mtx_unlock(&(cpstr)->que_mtx);                                  \
} while (0)

#define SCTP_MCORE_LOCK_INIT(cpstr) do {                                \
        mtx_init(&(cpstr)->core_mtx, "sctp-cpulck","cpu_proc_lock",     \
                 MTX_DEF | MTX_DUPOK);                                  \
} while (0)

#define SCTP_MCORE_DESTROY(cpstr) do {                                  \
        if (mtx_owned(&(cpstr)->core_mtx)) {                            \
                mtx_unlock(&(cpstr)->core_mtx);                         \
        }                                                               \
        mtx_destroy(&(cpstr)->core_mtx);                                \
} while (0)

#define SCTP_MCORE_LOCK(cpstr) do {                                     \
        mtx_lock(&(cpstr)->core_mtx);                                   \
} while (0)

#define SCTP_MCORE_UNLOCK(cpstr) do {                                   \
        mtx_unlock(&(cpstr)->core_mtx);                                 \
} while (0)

#define SCTP_IPI_ADDR_INIT() do {                                       \
        rw_init(&SCTP_BASE_INFO(ipi_addr_mtx), "sctp-addr");            \
} while (0)

#define SCTP_IPI_ADDR_DESTROY() do {                                    \
        if (rw_wowned(&SCTP_BASE_INFO(ipi_addr_mtx))) {                 \
                rw_wunlock(&SCTP_BASE_INFO(ipi_addr_mtx));              \
        }                                                               \
        rw_destroy(&SCTP_BASE_INFO(ipi_addr_mtx));                      \
} while (0)

#define SCTP_IPI_ADDR_RLOCK()   do {                                    \
        rw_rlock(&SCTP_BASE_INFO(ipi_addr_mtx));                        \
} while (0)

#define SCTP_IPI_ADDR_WLOCK()   do {                                    \
        rw_wlock(&SCTP_BASE_INFO(ipi_addr_mtx));                        \
} while (0)

#define SCTP_IPI_ADDR_RUNLOCK() do {                                    \
        rw_runlock(&SCTP_BASE_INFO(ipi_addr_mtx));                      \
} while (0)

#define SCTP_IPI_ADDR_WUNLOCK() do {                                    \
        rw_wunlock(&SCTP_BASE_INFO(ipi_addr_mtx));                      \
} while (0)

#define SCTP_IPI_ADDR_LOCK_ASSERT() do {                                \
        rw_assert(&SCTP_BASE_INFO(ipi_addr_mtx), RA_LOCKED);            \
} while (0)

#define SCTP_IPI_ADDR_WLOCK_ASSERT() do {                               \
        rw_assert(&SCTP_BASE_INFO(ipi_addr_mtx), RA_WLOCKED);           \
} while (0)

#define SCTP_IPI_ITERATOR_WQ_INIT() do {                                \
        mtx_init(&sctp_it_ctl.ipi_iterator_wq_mtx, "sctp-it-wq",        \
                 "sctp_it_wq", MTX_DEF);                                \
} while (0)

#define SCTP_IPI_ITERATOR_WQ_DESTROY() do {                             \
        mtx_destroy(&sctp_it_ctl.ipi_iterator_wq_mtx);                  \
} while (0)

#define SCTP_IPI_ITERATOR_WQ_LOCK() do {                                \
        mtx_lock(&sctp_it_ctl.ipi_iterator_wq_mtx);                     \
} while (0)

#define SCTP_IPI_ITERATOR_WQ_UNLOCK() do {                              \
        mtx_unlock(&sctp_it_ctl.ipi_iterator_wq_mtx);                   \
} while (0)

#define SCTP_IP_PKTLOG_INIT() do {                                      \
        mtx_init(&SCTP_BASE_INFO(ipi_pktlog_mtx), "sctp-pktlog",        \
                 "packetlog", MTX_DEF);                                 \
} while (0)

#define SCTP_IP_PKTLOG_DESTROY() do {                                   \
        mtx_destroy(&SCTP_BASE_INFO(ipi_pktlog_mtx));                   \
} while (0)

#define SCTP_IP_PKTLOG_LOCK()   do {                                    \
        mtx_lock(&SCTP_BASE_INFO(ipi_pktlog_mtx));                      \
} while (0)

#define SCTP_IP_PKTLOG_UNLOCK() do {                                    \
        mtx_unlock(&SCTP_BASE_INFO(ipi_pktlog_mtx));                    \
} while (0)

/*
 * The INP locks we will use for locking an SCTP endpoint, so for example if
 * we want to change something at the endpoint level for example random_store
 * or cookie secrets we lock the INP level.
 */

#define SCTP_INP_READ_LOCK_INIT(_inp) do {                              \
        mtx_init(&(_inp)->inp_rdata_mtx, "sctp-read", "inpr",           \
                 MTX_DEF | MTX_DUPOK);                                  \
} while (0)

#define SCTP_INP_READ_LOCK_DESTROY(_inp) do {                           \
        mtx_destroy(&(_inp)->inp_rdata_mtx);                            \
} while (0)

#define SCTP_INP_READ_LOCK(_inp) do {                                   \
        mtx_lock(&(_inp)->inp_rdata_mtx);                               \
} while (0)

#define SCTP_INP_READ_UNLOCK(_inp) do {                                 \
        mtx_unlock(&(_inp)->inp_rdata_mtx);                             \
} while (0)

#define SCTP_INP_READ_LOCK_ASSERT(_inp) do {                            \
        KASSERT(mtx_owned(&(_inp)->inp_rdata_mtx),                      \
                ("Don't own INP read queue lock"));                     \
} while (0)

#define SCTP_INP_LOCK_INIT(_inp) do {                                   \
        mtx_init(&(_inp)->inp_mtx, "sctp-inp", "inp",                   \
                 MTX_DEF | MTX_DUPOK);                                  \
} while (0)

#define SCTP_INP_LOCK_DESTROY(_inp) do {                                \
        mtx_destroy(&(_inp)->inp_mtx);                                  \
} while (0)

#define SCTP_INP_LOCK_CONTENDED(_inp)                                   \
        ((_inp)->inp_mtx.mtx_lock & MTX_WAITERS)

#define SCTP_INP_READ_CONTENDED(_inp)                                   \
        ((_inp)->inp_rdata_mtx.mtx_lock & MTX_WAITERS)

#ifdef SCTP_LOCK_LOGGING
#define SCTP_INP_RLOCK(_inp)    do {                                    \
        if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOCK_LOGGING_ENABLE) \
                sctp_log_lock(_inp, NULL, SCTP_LOG_LOCK_INP);           \
        mtx_lock(&(_inp)->inp_mtx);                                     \
} while (0)

#define SCTP_INP_WLOCK(_inp)    do {                                    \
        if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOCK_LOGGING_ENABLE) \
                sctp_log_lock(_inp, NULL, SCTP_LOG_LOCK_INP);           \
        mtx_lock(&(_inp)->inp_mtx);                                     \
} while (0)
#else
#define SCTP_INP_RLOCK(_inp) do {                                       \
        mtx_lock(&(_inp)->inp_mtx);                                     \
} while (0)

#define SCTP_INP_WLOCK(_inp) do {                                       \
        mtx_lock(&(_inp)->inp_mtx);                                     \
} while (0)
#endif

#define SCTP_INP_RUNLOCK(_inp) do {                                     \
        mtx_unlock(&(_inp)->inp_mtx);                                   \
} while (0)

#define SCTP_INP_WUNLOCK(_inp) do {                                     \
        mtx_unlock(&(_inp)->inp_mtx);                                   \
} while (0)

#define SCTP_INP_RLOCK_ASSERT(_inp) do {                                \
        KASSERT(mtx_owned(&(_inp)->inp_mtx),                            \
                ("Don't own INP read lock"));                           \
} while (0)

#define SCTP_INP_WLOCK_ASSERT(_inp) do {                                \
        KASSERT(mtx_owned(&(_inp)->inp_mtx),                            \
                ("Don't own INP write lock"));                          \
} while (0)

#define SCTP_INP_INCR_REF(_inp) atomic_add_int(&((_inp)->refcount), 1)
#define SCTP_INP_DECR_REF(_inp) atomic_add_int(&((_inp)->refcount), -1)

#define SCTP_ASOC_CREATE_LOCK_INIT(_inp) do {                           \
        mtx_init(&(_inp)->inp_create_mtx, "sctp-create", "inp_create",  \
                 MTX_DEF | MTX_DUPOK);                                  \
} while (0)

#define SCTP_ASOC_CREATE_LOCK_DESTROY(_inp) do {                        \
        mtx_destroy(&(_inp)->inp_create_mtx);                           \
} while (0)

#ifdef SCTP_LOCK_LOGGING
#define SCTP_ASOC_CREATE_LOCK(_inp) do {                                \
        if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOCK_LOGGING_ENABLE) \
                sctp_log_lock(_inp, NULL, SCTP_LOG_LOCK_CREATE);        \
        mtx_lock(&(_inp)->inp_create_mtx);                              \
} while (0)
#else
#define SCTP_ASOC_CREATE_LOCK(_inp) do {                                \
        mtx_lock(&(_inp)->inp_create_mtx);                              \
} while (0)
#endif

#define SCTP_ASOC_CREATE_UNLOCK(_inp) do {                              \
        mtx_unlock(&(_inp)->inp_create_mtx);                            \
} while (0)

#define SCTP_ASOC_CREATE_LOCK_CONTENDED(_inp)                           \
        ((_inp)->inp_create_mtx.mtx_lock & MTX_WAITERS)

/*
 * For the majority of things (once we have found the association) we will
 * lock the actual association mutex. This will protect all the assoiciation
 * level queues and streams and such. We will need to lock the socket layer
 * when we stuff data up into the receiving sb_mb. I.e. we will need to do an
 * extra SOCKBUF_LOCK(&so->so_rcv) even though the association is locked.
 */

#define SCTP_TCB_LOCK_INIT(_tcb) do {                                   \
        mtx_init(&(_tcb)->tcb_mtx, "sctp-tcb", "tcb",                   \
                 MTX_DEF | MTX_DUPOK);                                  \
} while (0)

#define SCTP_TCB_LOCK_DESTROY(_tcb) do {                                \
        mtx_destroy(&(_tcb)->tcb_mtx);                                  \
} while (0)

#ifdef SCTP_LOCK_LOGGING
#define SCTP_TCB_LOCK(_tcb) do {                                        \
        if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOCK_LOGGING_ENABLE) \
                sctp_log_lock(_tcb->sctp_ep, _tcb, SCTP_LOG_LOCK_TCB);  \
        mtx_lock(&(_tcb)->tcb_mtx);                                     \
} while (0)
#else
#define SCTP_TCB_LOCK(_tcb) do {                                        \
        mtx_lock(&(_tcb)->tcb_mtx);                                     \
} while (0)

#endif

#define SCTP_TCB_TRYLOCK(_tcb)                                          \
        mtx_trylock(&(_tcb)->tcb_mtx)

#define SCTP_TCB_UNLOCK(_tcb) do {                                      \
        mtx_unlock(&(_tcb)->tcb_mtx);                                   \
} while (0)

#define SCTP_TCB_UNLOCK_IFOWNED(_tcb) do {                              \
        if (mtx_owned(&(_tcb)->tcb_mtx))                                \
                mtx_unlock(&(_tcb)->tcb_mtx);                           \
} while (0)

#define SCTP_TCB_LOCK_ASSERT(_tcb) do {                                 \
        KASSERT(mtx_owned(&(_tcb)->tcb_mtx),                            \
                ("Don't own TCB lock"));                                \
} while (0)

#define SCTP_ITERATOR_LOCK_INIT() do {                                  \
        mtx_init(&sctp_it_ctl.it_mtx, "sctp-it", "iterator", MTX_DEF);  \
} while (0)

#define SCTP_ITERATOR_LOCK_DESTROY() do {                               \
        mtx_destroy(&sctp_it_ctl.it_mtx);                               \
} while (0)

#define SCTP_ITERATOR_LOCK() \
        do {                                                            \
                KASSERT(!mtx_owned(&sctp_it_ctl.it_mtx),                \
                        ("Own the iterator lock"));                     \
                mtx_lock(&sctp_it_ctl.it_mtx);                          \
        } while (0)

#define SCTP_ITERATOR_UNLOCK() do {                                     \
        mtx_unlock(&sctp_it_ctl.it_mtx);                                \
} while (0)

#define SCTP_WQ_ADDR_INIT() do {                                        \
        mtx_init(&SCTP_BASE_INFO(wq_addr_mtx),                          \
                 "sctp-addr-wq","sctp_addr_wq", MTX_DEF);               \
} while (0)

#define SCTP_WQ_ADDR_DESTROY() do  {                                    \
        if (mtx_owned(&SCTP_BASE_INFO(wq_addr_mtx))) {                  \
                mtx_unlock(&SCTP_BASE_INFO(wq_addr_mtx));               \
        }                                                               \
        mtx_destroy(&SCTP_BASE_INFO(wq_addr_mtx)); \
} while (0)

#define SCTP_WQ_ADDR_LOCK()     do {                                    \
        mtx_lock(&SCTP_BASE_INFO(wq_addr_mtx));                         \
} while (0)

#define SCTP_WQ_ADDR_UNLOCK() do {                                      \
                mtx_unlock(&SCTP_BASE_INFO(wq_addr_mtx));               \
} while (0)

#define SCTP_WQ_ADDR_LOCK_ASSERT() do {                                 \
        KASSERT(mtx_owned(&SCTP_BASE_INFO(wq_addr_mtx)),                \
                ("Don't own the ADDR-WQ lock"));                        \
} while (0)

#define SCTP_INCR_EP_COUNT() do {                                       \
        atomic_add_int(&SCTP_BASE_INFO(ipi_count_ep), 1);               \
} while (0)

#define SCTP_DECR_EP_COUNT() do {                                       \
        atomic_subtract_int(&SCTP_BASE_INFO(ipi_count_ep), 1);          \
} while (0)

#define SCTP_INCR_ASOC_COUNT() do {                                     \
        atomic_add_int(&SCTP_BASE_INFO(ipi_count_asoc), 1);             \
} while (0)

#define SCTP_DECR_ASOC_COUNT() do {                                     \
        atomic_subtract_int(&SCTP_BASE_INFO(ipi_count_asoc), 1);        \
} while (0)

#define SCTP_INCR_LADDR_COUNT() do {                                    \
        atomic_add_int(&SCTP_BASE_INFO(ipi_count_laddr), 1);            \
} while (0)

#define SCTP_DECR_LADDR_COUNT() do {                                    \
        atomic_subtract_int(&SCTP_BASE_INFO(ipi_count_laddr), 1);       \
} while (0)

#define SCTP_INCR_RADDR_COUNT() do {                                    \
        atomic_add_int(&SCTP_BASE_INFO(ipi_count_raddr), 1);            \
} while (0)

#define SCTP_DECR_RADDR_COUNT() do {                                    \
        atomic_subtract_int(&SCTP_BASE_INFO(ipi_count_raddr),1);        \
} while (0)

#define SCTP_INCR_CHK_COUNT() do {                                      \
        atomic_add_int(&SCTP_BASE_INFO(ipi_count_chunk), 1);            \
} while (0)

#define SCTP_DECR_CHK_COUNT() do {                                      \
        KASSERT(SCTP_BASE_INFO(ipi_count_chunk) > 0,                    \
                ("ipi_count_chunk would become negative"));             \
        if (SCTP_BASE_INFO(ipi_count_chunk) != 0)                       \
                atomic_subtract_int(&SCTP_BASE_INFO(ipi_count_chunk),   \
                                    1);                                 \
} while (0)

#define SCTP_INCR_READQ_COUNT() do {                                    \
        atomic_add_int(&SCTP_BASE_INFO(ipi_count_readq), 1);            \
} while (0)

#define SCTP_DECR_READQ_COUNT() do {                                    \
        atomic_subtract_int(&SCTP_BASE_INFO(ipi_count_readq), 1);       \
} while (0)

#define SCTP_INCR_STRMOQ_COUNT() do {                                   \
        atomic_add_int(&SCTP_BASE_INFO(ipi_count_strmoq), 1);           \
} while (0)

#define SCTP_DECR_STRMOQ_COUNT() do {                                   \
        atomic_subtract_int(&SCTP_BASE_INFO(ipi_count_strmoq), 1);      \
} while (0)

#if defined(SCTP_SO_LOCK_TESTING)
#define SCTP_INP_SO(sctpinp)                                            \
        (sctpinp)->ip_inp.inp.inp_socket
#define SCTP_SOCKET_LOCK(so, refcnt)
#define SCTP_SOCKET_UNLOCK(so, refcnt)
#endif

#endif