/*- * Copyright (c) 2012 The FreeBSD Foundation * All rights reserved. * * 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 __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "icl.h" #include "iscsi_proto.h" SYSCTL_NODE(_kern, OID_AUTO, icl, CTLFLAG_RD, 0, "iSCSI Common Layer"); static int debug = 1; SYSCTL_INT(_kern_icl, OID_AUTO, debug, CTLFLAG_RWTUN, &debug, 0, "Enable debug messages"); static int coalesce = 1; SYSCTL_INT(_kern_icl, OID_AUTO, coalesce, CTLFLAG_RWTUN, &coalesce, 0, "Try to coalesce PDUs before sending"); static int partial_receive_len = 128 * 1024; SYSCTL_INT(_kern_icl, OID_AUTO, partial_receive_len, CTLFLAG_RWTUN, &partial_receive_len, 0, "Minimum read size for partially received " "data segment"); static int sendspace = 1048576; SYSCTL_INT(_kern_icl, OID_AUTO, sendspace, CTLFLAG_RWTUN, &sendspace, 0, "Default send socket buffer size"); static int recvspace = 1048576; SYSCTL_INT(_kern_icl, OID_AUTO, recvspace, CTLFLAG_RWTUN, &recvspace, 0, "Default receive socket buffer size"); static uma_zone_t icl_conn_zone; static uma_zone_t icl_pdu_zone; static volatile u_int icl_ncons; #define ICL_DEBUG(X, ...) \ do { \ if (debug > 1) \ printf("%s: " X "\n", __func__, ## __VA_ARGS__);\ } while (0) #define ICL_WARN(X, ...) \ do { \ if (debug > 0) { \ printf("WARNING: %s: " X "\n", \ __func__, ## __VA_ARGS__); \ } \ } while (0) #define ICL_CONN_LOCK(X) mtx_lock(X->ic_lock) #define ICL_CONN_UNLOCK(X) mtx_unlock(X->ic_lock) #define ICL_CONN_LOCK_ASSERT(X) mtx_assert(X->ic_lock, MA_OWNED) #define ICL_CONN_LOCK_ASSERT_NOT(X) mtx_assert(X->ic_lock, MA_NOTOWNED) STAILQ_HEAD(icl_pdu_stailq, icl_pdu); static void icl_conn_fail(struct icl_conn *ic) { if (ic->ic_socket == NULL) return; /* * XXX */ ic->ic_socket->so_error = EDOOFUS; (ic->ic_error)(ic); } static struct mbuf * icl_conn_receive(struct icl_conn *ic, size_t len) { struct uio uio; struct socket *so; struct mbuf *m; int error, flags; so = ic->ic_socket; memset(&uio, 0, sizeof(uio)); uio.uio_resid = len; flags = MSG_DONTWAIT; error = soreceive(so, NULL, &uio, &m, NULL, &flags); if (error != 0) { ICL_DEBUG("soreceive error %d", error); return (NULL); } if (uio.uio_resid != 0) { m_freem(m); ICL_DEBUG("short read"); return (NULL); } return (m); } static struct icl_pdu * icl_pdu_new(struct icl_conn *ic, int flags) { struct icl_pdu *ip; #ifdef DIAGNOSTIC refcount_acquire(&ic->ic_outstanding_pdus); #endif ip = uma_zalloc(icl_pdu_zone, flags | M_ZERO); if (ip == NULL) { ICL_WARN("failed to allocate %zd bytes", sizeof(*ip)); #ifdef DIAGNOSTIC refcount_release(&ic->ic_outstanding_pdus); #endif return (NULL); } ip->ip_conn = ic; return (ip); } void icl_pdu_free(struct icl_pdu *ip) { struct icl_conn *ic; ic = ip->ip_conn; m_freem(ip->ip_bhs_mbuf); m_freem(ip->ip_ahs_mbuf); m_freem(ip->ip_data_mbuf); uma_zfree(icl_pdu_zone, ip); #ifdef DIAGNOSTIC refcount_release(&ic->ic_outstanding_pdus); #endif } /* * Allocate icl_pdu with empty BHS to fill up by the caller. */ struct icl_pdu * icl_pdu_new_bhs(struct icl_conn *ic, int flags) { struct icl_pdu *ip; ip = icl_pdu_new(ic, flags); if (ip == NULL) return (NULL); ip->ip_bhs_mbuf = m_getm2(NULL, sizeof(struct iscsi_bhs), flags, MT_DATA, M_PKTHDR); if (ip->ip_bhs_mbuf == NULL) { ICL_WARN("failed to allocate %zd bytes", sizeof(*ip)); icl_pdu_free(ip); return (NULL); } ip->ip_bhs = mtod(ip->ip_bhs_mbuf, struct iscsi_bhs *); memset(ip->ip_bhs, 0, sizeof(struct iscsi_bhs)); ip->ip_bhs_mbuf->m_len = sizeof(struct iscsi_bhs); return (ip); } static int icl_pdu_ahs_length(const struct icl_pdu *request) { return (request->ip_bhs->bhs_total_ahs_len * 4); } size_t icl_pdu_data_segment_length(const struct icl_pdu *request) { uint32_t len = 0; len += request->ip_bhs->bhs_data_segment_len[0]; len <<= 8; len += request->ip_bhs->bhs_data_segment_len[1]; len <<= 8; len += request->ip_bhs->bhs_data_segment_len[2]; return (len); } static void icl_pdu_set_data_segment_length(struct icl_pdu *response, uint32_t len) { response->ip_bhs->bhs_data_segment_len[2] = len; response->ip_bhs->bhs_data_segment_len[1] = len >> 8; response->ip_bhs->bhs_data_segment_len[0] = len >> 16; } static size_t icl_pdu_padding(const struct icl_pdu *ip) { if ((ip->ip_data_len % 4) != 0) return (4 - (ip->ip_data_len % 4)); return (0); } static size_t icl_pdu_size(const struct icl_pdu *response) { size_t len; KASSERT(response->ip_ahs_len == 0, ("responding with AHS")); len = sizeof(struct iscsi_bhs) + response->ip_data_len + icl_pdu_padding(response); if (response->ip_conn->ic_header_crc32c) len += ISCSI_HEADER_DIGEST_SIZE; if (response->ip_data_len != 0 && response->ip_conn->ic_data_crc32c) len += ISCSI_DATA_DIGEST_SIZE; return (len); } static int icl_pdu_receive_bhs(struct icl_pdu *request, size_t *availablep) { struct mbuf *m; m = icl_conn_receive(request->ip_conn, sizeof(struct iscsi_bhs)); if (m == NULL) { ICL_DEBUG("failed to receive BHS"); return (-1); } request->ip_bhs_mbuf = m_pullup(m, sizeof(struct iscsi_bhs)); if (request->ip_bhs_mbuf == NULL) { ICL_WARN("m_pullup failed"); return (-1); } request->ip_bhs = mtod(request->ip_bhs_mbuf, struct iscsi_bhs *); /* * XXX: For architectures with strict alignment requirements * we may need to allocate ip_bhs and copy the data into it. * For some reason, though, not doing this doesn't seem * to cause problems; tested on sparc64. */ *availablep -= sizeof(struct iscsi_bhs); return (0); } static int icl_pdu_receive_ahs(struct icl_pdu *request, size_t *availablep) { request->ip_ahs_len = icl_pdu_ahs_length(request); if (request->ip_ahs_len == 0) return (0); request->ip_ahs_mbuf = icl_conn_receive(request->ip_conn, request->ip_ahs_len); if (request->ip_ahs_mbuf == NULL) { ICL_DEBUG("failed to receive AHS"); return (-1); } *availablep -= request->ip_ahs_len; return (0); } static uint32_t icl_mbuf_to_crc32c(const struct mbuf *m0) { uint32_t digest = 0xffffffff; const struct mbuf *m; for (m = m0; m != NULL; m = m->m_next) digest = calculate_crc32c(digest, mtod(m, const void *), m->m_len); digest = digest ^ 0xffffffff; return (digest); } static int icl_pdu_check_header_digest(struct icl_pdu *request, size_t *availablep) { struct mbuf *m; uint32_t received_digest, valid_digest; if (request->ip_conn->ic_header_crc32c == false) return (0); m = icl_conn_receive(request->ip_conn, ISCSI_HEADER_DIGEST_SIZE); if (m == NULL) { ICL_DEBUG("failed to receive header digest"); return (-1); } CTASSERT(sizeof(received_digest) == ISCSI_HEADER_DIGEST_SIZE); m_copydata(m, 0, ISCSI_HEADER_DIGEST_SIZE, (void *)&received_digest); m_freem(m); *availablep -= ISCSI_HEADER_DIGEST_SIZE; /* * XXX: Handle AHS. */ valid_digest = icl_mbuf_to_crc32c(request->ip_bhs_mbuf); if (received_digest != valid_digest) { ICL_WARN("header digest check failed; got 0x%x, " "should be 0x%x", received_digest, valid_digest); return (-1); } return (0); } /* * Return the number of bytes that should be waiting in the receive socket * before icl_pdu_receive_data_segment() gets called. */ static size_t icl_pdu_data_segment_receive_len(const struct icl_pdu *request) { size_t len; len = icl_pdu_data_segment_length(request); if (len == 0) return (0); /* * Account for the parts of data segment already read from * the socket buffer. */ KASSERT(len > request->ip_data_len, ("len <= request->ip_data_len")); len -= request->ip_data_len; /* * Don't always wait for the full data segment to be delivered * to the socket; this might badly affect performance due to * TCP window scaling. */ if (len > partial_receive_len) { #if 0 ICL_DEBUG("need %zd bytes of data, limiting to %zd", len, partial_receive_len)); #endif len = partial_receive_len; return (len); } /* * Account for padding. Note that due to the way code is written, * the icl_pdu_receive_data_segment() must always receive padding * along with the last part of data segment, because it would be * impossible to tell whether we've already received the full data * segment including padding, or without it. */ if ((len % 4) != 0) len += 4 - (len % 4); #if 0 ICL_DEBUG("need %zd bytes of data", len)); #endif return (len); } static int icl_pdu_receive_data_segment(struct icl_pdu *request, size_t *availablep, bool *more_neededp) { struct icl_conn *ic; size_t len, padding = 0; struct mbuf *m; ic = request->ip_conn; *more_neededp = false; ic->ic_receive_len = 0; len = icl_pdu_data_segment_length(request); if (len == 0) return (0); if ((len % 4) != 0) padding = 4 - (len % 4); /* * Account for already received parts of data segment. */ KASSERT(len > request->ip_data_len, ("len <= request->ip_data_len")); len -= request->ip_data_len; if (len + padding > *availablep) { /* * Not enough data in the socket buffer. Receive as much * as we can. Don't receive padding, since, obviously, it's * not the end of data segment yet. */ #if 0 ICL_DEBUG("limited from %zd to %zd", len + padding, *availablep - padding)); #endif len = *availablep - padding; *more_neededp = true; padding = 0; } /* * Must not try to receive padding without at least one byte * of actual data segment. */ if (len > 0) { m = icl_conn_receive(request->ip_conn, len + padding); if (m == NULL) { ICL_DEBUG("failed to receive data segment"); return (-1); } if (request->ip_data_mbuf == NULL) request->ip_data_mbuf = m; else m_cat(request->ip_data_mbuf, m); request->ip_data_len += len; *availablep -= len + padding; } else ICL_DEBUG("len 0"); if (*more_neededp) ic->ic_receive_len = icl_pdu_data_segment_receive_len(request); return (0); } static int icl_pdu_check_data_digest(struct icl_pdu *request, size_t *availablep) { struct mbuf *m; uint32_t received_digest, valid_digest; if (request->ip_conn->ic_data_crc32c == false) return (0); if (request->ip_data_len == 0) return (0); m = icl_conn_receive(request->ip_conn, ISCSI_DATA_DIGEST_SIZE); if (m == NULL) { ICL_DEBUG("failed to receive data digest"); return (-1); } CTASSERT(sizeof(received_digest) == ISCSI_DATA_DIGEST_SIZE); m_copydata(m, 0, ISCSI_DATA_DIGEST_SIZE, (void *)&received_digest); m_freem(m); *availablep -= ISCSI_DATA_DIGEST_SIZE; /* * Note that ip_data_mbuf also contains padding; since digest * calculation is supposed to include that, we iterate over * the entire ip_data_mbuf chain, not just ip_data_len bytes of it. */ valid_digest = icl_mbuf_to_crc32c(request->ip_data_mbuf); if (received_digest != valid_digest) { ICL_WARN("data digest check failed; got 0x%x, " "should be 0x%x", received_digest, valid_digest); return (-1); } return (0); } /* * Somewhat contrary to the name, this attempts to receive only one * "part" of PDU at a time; call it repeatedly until it returns non-NULL. */ static struct icl_pdu * icl_conn_receive_pdu(struct icl_conn *ic, size_t *availablep) { struct icl_pdu *request; struct socket *so; size_t len; int error; bool more_needed; so = ic->ic_socket; if (ic->ic_receive_state == ICL_CONN_STATE_BHS) { KASSERT(ic->ic_receive_pdu == NULL, ("ic->ic_receive_pdu != NULL")); request = icl_pdu_new(ic, M_NOWAIT); if (request == NULL) { ICL_DEBUG("failed to allocate PDU; " "dropping connection"); icl_conn_fail(ic); return (NULL); } ic->ic_receive_pdu = request; } else { KASSERT(ic->ic_receive_pdu != NULL, ("ic->ic_receive_pdu == NULL")); request = ic->ic_receive_pdu; } if (*availablep < ic->ic_receive_len) { #if 0 ICL_DEBUG("not enough data; need %zd, " "have %zd", ic->ic_receive_len, *availablep); #endif return (NULL); } switch (ic->ic_receive_state) { case ICL_CONN_STATE_BHS: //ICL_DEBUG("receiving BHS"); error = icl_pdu_receive_bhs(request, availablep); if (error != 0) { ICL_DEBUG("failed to receive BHS; " "dropping connection"); break; } /* * We don't enforce any limit for AHS length; * its length is stored in 8 bit field. */ len = icl_pdu_data_segment_length(request); if (len > ic->ic_max_data_segment_length) { ICL_WARN("received data segment " "length %zd is larger than negotiated " "MaxDataSegmentLength %zd; " "dropping connection", len, ic->ic_max_data_segment_length); error = EINVAL; break; } ic->ic_receive_state = ICL_CONN_STATE_AHS; ic->ic_receive_len = icl_pdu_ahs_length(request); break; case ICL_CONN_STATE_AHS: //ICL_DEBUG("receiving AHS"); error = icl_pdu_receive_ahs(request, availablep); if (error != 0) { ICL_DEBUG("failed to receive AHS; " "dropping connection"); break; } ic->ic_receive_state = ICL_CONN_STATE_HEADER_DIGEST; if (ic->ic_header_crc32c == false) ic->ic_receive_len = 0; else ic->ic_receive_len = ISCSI_HEADER_DIGEST_SIZE; break; case ICL_CONN_STATE_HEADER_DIGEST: //ICL_DEBUG("receiving header digest"); error = icl_pdu_check_header_digest(request, availablep); if (error != 0) { ICL_DEBUG("header digest failed; " "dropping connection"); break; } ic->ic_receive_state = ICL_CONN_STATE_DATA; ic->ic_receive_len = icl_pdu_data_segment_receive_len(request); break; case ICL_CONN_STATE_DATA: //ICL_DEBUG("receiving data segment"); error = icl_pdu_receive_data_segment(request, availablep, &more_needed); if (error != 0) { ICL_DEBUG("failed to receive data segment;" "dropping connection"); break; } if (more_needed) break; ic->ic_receive_state = ICL_CONN_STATE_DATA_DIGEST; if (request->ip_data_len == 0 || ic->ic_data_crc32c == false) ic->ic_receive_len = 0; else ic->ic_receive_len = ISCSI_DATA_DIGEST_SIZE; break; case ICL_CONN_STATE_DATA_DIGEST: //ICL_DEBUG("receiving data digest"); error = icl_pdu_check_data_digest(request, availablep); if (error != 0) { ICL_DEBUG("data digest failed; " "dropping connection"); break; } /* * We've received complete PDU; reset the receive state machine * and return the PDU. */ ic->ic_receive_state = ICL_CONN_STATE_BHS; ic->ic_receive_len = sizeof(struct iscsi_bhs); ic->ic_receive_pdu = NULL; return (request); default: panic("invalid ic_receive_state %d\n", ic->ic_receive_state); } if (error != 0) { /* * Don't free the PDU; it's pointed to by ic->ic_receive_pdu * and will get freed in icl_conn_close(). */ icl_conn_fail(ic); } return (NULL); } static void icl_conn_receive_pdus(struct icl_conn *ic, size_t available) { struct icl_pdu *response; struct socket *so; so = ic->ic_socket; /* * This can never happen; we're careful to only mess with ic->ic_socket * pointer when the send/receive threads are not running. */ KASSERT(so != NULL, ("NULL socket")); for (;;) { if (ic->ic_disconnecting) return; if (so->so_error != 0) { ICL_DEBUG("connection error %d; " "dropping connection", so->so_error); icl_conn_fail(ic); return; } /* * Loop until we have a complete PDU or there is not enough * data in the socket buffer. */ if (available < ic->ic_receive_len) { #if 0 ICL_DEBUG("not enough data; have %zd, " "need %zd", available, ic->ic_receive_len); #endif return; } response = icl_conn_receive_pdu(ic, &available); if (response == NULL) continue; if (response->ip_ahs_len > 0) { ICL_WARN("received PDU with unsupported " "AHS; opcode 0x%x; dropping connection", response->ip_bhs->bhs_opcode); icl_pdu_free(response); icl_conn_fail(ic); return; } (ic->ic_receive)(response); } } static void icl_receive_thread(void *arg) { struct icl_conn *ic; size_t available; struct socket *so; ic = arg; so = ic->ic_socket; ICL_CONN_LOCK(ic); ic->ic_receive_running = true; ICL_CONN_UNLOCK(ic); for (;;) { if (ic->ic_disconnecting) { //ICL_DEBUG("terminating"); break; } /* * Set the low watermark, to be checked by * soreadable() in icl_soupcall_receive() * to avoid unneccessary wakeups until there * is enough data received to read the PDU. */ SOCKBUF_LOCK(&so->so_rcv); available = so->so_rcv.sb_cc; if (available < ic->ic_receive_len) { so->so_rcv.sb_lowat = ic->ic_receive_len; cv_wait(&ic->ic_receive_cv, &so->so_rcv.sb_mtx); } else so->so_rcv.sb_lowat = so->so_rcv.sb_hiwat + 1; SOCKBUF_UNLOCK(&so->so_rcv); icl_conn_receive_pdus(ic, available); } ICL_CONN_LOCK(ic); ic->ic_receive_running = false; ICL_CONN_UNLOCK(ic); kthread_exit(); } static int icl_soupcall_receive(struct socket *so, void *arg, int waitflag) { struct icl_conn *ic; if (!soreadable(so)) return (SU_OK); ic = arg; cv_signal(&ic->ic_receive_cv); return (SU_OK); } static int icl_pdu_finalize(struct icl_pdu *request) { size_t padding, pdu_len; uint32_t digest, zero = 0; int ok; struct icl_conn *ic; ic = request->ip_conn; icl_pdu_set_data_segment_length(request, request->ip_data_len); pdu_len = icl_pdu_size(request); if (ic->ic_header_crc32c) { digest = icl_mbuf_to_crc32c(request->ip_bhs_mbuf); ok = m_append(request->ip_bhs_mbuf, sizeof(digest), (void *)&digest); if (ok != 1) { ICL_WARN("failed to append header digest"); return (1); } } if (request->ip_data_len != 0) { padding = icl_pdu_padding(request); if (padding > 0) { ok = m_append(request->ip_data_mbuf, padding, (void *)&zero); if (ok != 1) { ICL_WARN("failed to append padding"); return (1); } } if (ic->ic_data_crc32c) { digest = icl_mbuf_to_crc32c(request->ip_data_mbuf); ok = m_append(request->ip_data_mbuf, sizeof(digest), (void *)&digest); if (ok != 1) { ICL_WARN("failed to append data digest"); return (1); } } m_cat(request->ip_bhs_mbuf, request->ip_data_mbuf); request->ip_data_mbuf = NULL; } request->ip_bhs_mbuf->m_pkthdr.len = pdu_len; return (0); } static void icl_conn_send_pdus(struct icl_conn *ic, struct icl_pdu_stailq *queue) { struct icl_pdu *request, *request2; struct socket *so; size_t available, size, size2; int coalesced, error; ICL_CONN_LOCK_ASSERT_NOT(ic); so = ic->ic_socket; SOCKBUF_LOCK(&so->so_snd); /* * Check how much space do we have for transmit. We can't just * call sosend() and retry when we get EWOULDBLOCK or EMSGSIZE, * as it always frees the mbuf chain passed to it, even in case * of error. */ available = sbspace(&so->so_snd); /* * Notify the socket upcall that we don't need wakeups * for the time being. */ so->so_snd.sb_lowat = so->so_snd.sb_hiwat + 1; SOCKBUF_UNLOCK(&so->so_snd); while (!STAILQ_EMPTY(queue)) { if (ic->ic_disconnecting) return; request = STAILQ_FIRST(queue); size = icl_pdu_size(request); if (available < size) { /* * Set the low watermark, to be checked by * sowriteable() in icl_soupcall_send() * to avoid unneccessary wakeups until there * is enough space for the PDU to fit. */ SOCKBUF_LOCK(&so->so_snd); available = sbspace(&so->so_snd); if (available < size) { #if 1 ICL_DEBUG("no space to send; " "have %zd, need %zd", available, size); #endif so->so_snd.sb_lowat = size; SOCKBUF_UNLOCK(&so->so_snd); return; } SOCKBUF_UNLOCK(&so->so_snd); } STAILQ_REMOVE_HEAD(queue, ip_next); error = icl_pdu_finalize(request); if (error != 0) { ICL_DEBUG("failed to finalize PDU; " "dropping connection"); icl_conn_fail(ic); icl_pdu_free(request); return; } if (coalesce) { coalesced = 1; for (;;) { request2 = STAILQ_FIRST(queue); if (request2 == NULL) break; size2 = icl_pdu_size(request2); if (available < size + size2) break; STAILQ_REMOVE_HEAD(queue, ip_next); error = icl_pdu_finalize(request2); if (error != 0) { ICL_DEBUG("failed to finalize PDU; " "dropping connection"); icl_conn_fail(ic); icl_pdu_free(request); icl_pdu_free(request2); return; } m_cat(request->ip_bhs_mbuf, request2->ip_bhs_mbuf); request2->ip_bhs_mbuf = NULL; request->ip_bhs_mbuf->m_pkthdr.len += size2; size += size2; STAILQ_REMOVE_AFTER(queue, request, ip_next); icl_pdu_free(request2); coalesced++; } #if 0 if (coalesced > 1) { ICL_DEBUG("coalesced %d PDUs into %zd bytes", coalesced, size); } #endif } available -= size; error = sosend(so, NULL, NULL, request->ip_bhs_mbuf, NULL, MSG_DONTWAIT, curthread); request->ip_bhs_mbuf = NULL; /* Sosend consumes the mbuf. */ if (error != 0) { ICL_DEBUG("failed to send PDU, error %d; " "dropping connection", error); icl_conn_fail(ic); icl_pdu_free(request); return; } icl_pdu_free(request); } } static void icl_send_thread(void *arg) { struct icl_conn *ic; struct icl_pdu_stailq queue; ic = arg; STAILQ_INIT(&queue); ICL_CONN_LOCK(ic); ic->ic_send_running = true; for (;;) { if (ic->ic_disconnecting) { //ICL_DEBUG("terminating"); break; } for (;;) { /* * If the local queue is empty, populate it from * the main one. This way the icl_conn_send_pdus() * can go through all the queued PDUs without holding * any locks. */ if (STAILQ_EMPTY(&queue)) STAILQ_SWAP(&ic->ic_to_send, &queue, icl_pdu); ic->ic_check_send_space = false; ICL_CONN_UNLOCK(ic); icl_conn_send_pdus(ic, &queue); ICL_CONN_LOCK(ic); /* * The icl_soupcall_send() was called since the last * call to sbspace(); go around; */ if (ic->ic_check_send_space) continue; /* * Local queue is empty, but we still have PDUs * in the main one; go around. */ if (STAILQ_EMPTY(&queue) && !STAILQ_EMPTY(&ic->ic_to_send)) continue; /* * There might be some stuff in the local queue, * which didn't get sent due to not having enough send * space. Wait for socket upcall. */ break; } cv_wait(&ic->ic_send_cv, ic->ic_lock); } /* * We're exiting; move PDUs back to the main queue, so they can * get freed properly. At this point ordering doesn't matter. */ STAILQ_CONCAT(&ic->ic_to_send, &queue); ic->ic_send_running = false; ICL_CONN_UNLOCK(ic); kthread_exit(); } static int icl_soupcall_send(struct socket *so, void *arg, int waitflag) { struct icl_conn *ic; if (!sowriteable(so)) return (SU_OK); ic = arg; ICL_CONN_LOCK(ic); ic->ic_check_send_space = true; ICL_CONN_UNLOCK(ic); cv_signal(&ic->ic_send_cv); return (SU_OK); } int icl_pdu_append_data(struct icl_pdu *request, const void *addr, size_t len, int flags) { struct mbuf *mb, *newmb; size_t copylen, off = 0; KASSERT(len > 0, ("len == 0")); newmb = m_getm2(NULL, len, flags, MT_DATA, M_PKTHDR); if (newmb == NULL) { ICL_WARN("failed to allocate mbuf for %zd bytes", len); return (ENOMEM); } for (mb = newmb; mb != NULL; mb = mb->m_next) { copylen = min(M_TRAILINGSPACE(mb), len - off); memcpy(mtod(mb, char *), (const char *)addr + off, copylen); mb->m_len = copylen; off += copylen; } KASSERT(off == len, ("%s: off != len", __func__)); if (request->ip_data_mbuf == NULL) { request->ip_data_mbuf = newmb; request->ip_data_len = len; } else { m_cat(request->ip_data_mbuf, newmb); request->ip_data_len += len; } return (0); } void icl_pdu_get_data(struct icl_pdu *ip, size_t off, void *addr, size_t len) { m_copydata(ip->ip_data_mbuf, off, len, addr); } void icl_pdu_queue(struct icl_pdu *ip) { struct icl_conn *ic; ic = ip->ip_conn; ICL_CONN_LOCK_ASSERT(ic); if (ic->ic_disconnecting || ic->ic_socket == NULL) { ICL_DEBUG("icl_pdu_queue on closed connection"); icl_pdu_free(ip); return; } if (!STAILQ_EMPTY(&ic->ic_to_send)) { STAILQ_INSERT_TAIL(&ic->ic_to_send, ip, ip_next); /* * If the queue is not empty, someone else had already * signaled the send thread; no need to do that again, * just return. */ return; } STAILQ_INSERT_TAIL(&ic->ic_to_send, ip, ip_next); cv_signal(&ic->ic_send_cv); } struct icl_conn * icl_conn_new(const char *name, struct mtx *lock) { struct icl_conn *ic; refcount_acquire(&icl_ncons); ic = uma_zalloc(icl_conn_zone, M_WAITOK | M_ZERO); STAILQ_INIT(&ic->ic_to_send); ic->ic_lock = lock; cv_init(&ic->ic_send_cv, "icl_tx"); cv_init(&ic->ic_receive_cv, "icl_rx"); #ifdef DIAGNOSTIC refcount_init(&ic->ic_outstanding_pdus, 0); #endif ic->ic_max_data_segment_length = ICL_MAX_DATA_SEGMENT_LENGTH; ic->ic_name = name; return (ic); } void icl_conn_free(struct icl_conn *ic) { cv_destroy(&ic->ic_send_cv); cv_destroy(&ic->ic_receive_cv); uma_zfree(icl_conn_zone, ic); refcount_release(&icl_ncons); } static int icl_conn_start(struct icl_conn *ic) { size_t minspace; struct sockopt opt; int error, one = 1; ICL_CONN_LOCK(ic); /* * XXX: Ugly hack. */ if (ic->ic_socket == NULL) { ICL_CONN_UNLOCK(ic); return (EINVAL); } ic->ic_receive_state = ICL_CONN_STATE_BHS; ic->ic_receive_len = sizeof(struct iscsi_bhs); ic->ic_disconnecting = false; ICL_CONN_UNLOCK(ic); /* * For sendspace, this is required because the current code cannot * send a PDU in pieces; thus, the minimum buffer size is equal * to the maximum PDU size. "+4" is to account for possible padding. * * What we should actually do here is to use autoscaling, but set * some minimal buffer size to "minspace". I don't know a way to do * that, though. */ minspace = sizeof(struct iscsi_bhs) + ic->ic_max_data_segment_length + ISCSI_HEADER_DIGEST_SIZE + ISCSI_DATA_DIGEST_SIZE + 4; if (sendspace < minspace) { ICL_WARN("kern.icl.sendspace too low; must be at least %zd", minspace); sendspace = minspace; } if (recvspace < minspace) { ICL_WARN("kern.icl.recvspace too low; must be at least %zd", minspace); recvspace = minspace; } error = soreserve(ic->ic_socket, sendspace, recvspace); if (error != 0) { ICL_WARN("soreserve failed with error %d", error); icl_conn_close(ic); return (error); } /* * Disable Nagle. */ bzero(&opt, sizeof(opt)); opt.sopt_dir = SOPT_SET; opt.sopt_level = IPPROTO_TCP; opt.sopt_name = TCP_NODELAY; opt.sopt_val = &one; opt.sopt_valsize = sizeof(one); error = sosetopt(ic->ic_socket, &opt); if (error != 0) { ICL_WARN("disabling TCP_NODELAY failed with error %d", error); icl_conn_close(ic); return (error); } /* * Start threads. */ error = kthread_add(icl_send_thread, ic, NULL, NULL, 0, 0, "%stx", ic->ic_name); if (error != 0) { ICL_WARN("kthread_add(9) failed with error %d", error); icl_conn_close(ic); return (error); } error = kthread_add(icl_receive_thread, ic, NULL, NULL, 0, 0, "%srx", ic->ic_name); if (error != 0) { ICL_WARN("kthread_add(9) failed with error %d", error); icl_conn_close(ic); return (error); } /* * Register socket upcall, to get notified about incoming PDUs * and free space to send outgoing ones. */ SOCKBUF_LOCK(&ic->ic_socket->so_snd); soupcall_set(ic->ic_socket, SO_SND, icl_soupcall_send, ic); SOCKBUF_UNLOCK(&ic->ic_socket->so_snd); SOCKBUF_LOCK(&ic->ic_socket->so_rcv); soupcall_set(ic->ic_socket, SO_RCV, icl_soupcall_receive, ic); SOCKBUF_UNLOCK(&ic->ic_socket->so_rcv); return (0); } int icl_conn_handoff(struct icl_conn *ic, int fd) { struct file *fp; struct socket *so; cap_rights_t rights; int error; ICL_CONN_LOCK_ASSERT_NOT(ic); /* * Steal the socket from userland. */ error = fget(curthread, fd, cap_rights_init(&rights, CAP_SOCK_CLIENT), &fp); if (error != 0) return (error); if (fp->f_type != DTYPE_SOCKET) { fdrop(fp, curthread); return (EINVAL); } so = fp->f_data; if (so->so_type != SOCK_STREAM) { fdrop(fp, curthread); return (EINVAL); } ICL_CONN_LOCK(ic); if (ic->ic_socket != NULL) { ICL_CONN_UNLOCK(ic); fdrop(fp, curthread); return (EBUSY); } ic->ic_socket = fp->f_data; fp->f_ops = &badfileops; fp->f_data = NULL; fdrop(fp, curthread); ICL_CONN_UNLOCK(ic); error = icl_conn_start(ic); return (error); } void icl_conn_shutdown(struct icl_conn *ic) { ICL_CONN_LOCK_ASSERT_NOT(ic); ICL_CONN_LOCK(ic); if (ic->ic_socket == NULL) { ICL_CONN_UNLOCK(ic); return; } ICL_CONN_UNLOCK(ic); soshutdown(ic->ic_socket, SHUT_RDWR); } void icl_conn_close(struct icl_conn *ic) { struct icl_pdu *pdu; ICL_CONN_LOCK_ASSERT_NOT(ic); ICL_CONN_LOCK(ic); if (ic->ic_socket == NULL) { ICL_CONN_UNLOCK(ic); return; } /* * Deregister socket upcalls. */ ICL_CONN_UNLOCK(ic); SOCKBUF_LOCK(&ic->ic_socket->so_snd); if (ic->ic_socket->so_snd.sb_upcall != NULL) soupcall_clear(ic->ic_socket, SO_SND); SOCKBUF_UNLOCK(&ic->ic_socket->so_snd); SOCKBUF_LOCK(&ic->ic_socket->so_rcv); if (ic->ic_socket->so_rcv.sb_upcall != NULL) soupcall_clear(ic->ic_socket, SO_RCV); SOCKBUF_UNLOCK(&ic->ic_socket->so_rcv); ICL_CONN_LOCK(ic); ic->ic_disconnecting = true; /* * Wake up the threads, so they can properly terminate. */ cv_signal(&ic->ic_receive_cv); cv_signal(&ic->ic_send_cv); while (ic->ic_receive_running || ic->ic_send_running) { //ICL_DEBUG("waiting for send/receive threads to terminate"); ICL_CONN_UNLOCK(ic); cv_signal(&ic->ic_receive_cv); cv_signal(&ic->ic_send_cv); pause("icl_close", 1 * hz); ICL_CONN_LOCK(ic); } //ICL_DEBUG("send/receive threads terminated"); ICL_CONN_UNLOCK(ic); soclose(ic->ic_socket); ICL_CONN_LOCK(ic); ic->ic_socket = NULL; if (ic->ic_receive_pdu != NULL) { //ICL_DEBUG("freeing partially received PDU"); icl_pdu_free(ic->ic_receive_pdu); ic->ic_receive_pdu = NULL; } /* * Remove any outstanding PDUs from the send queue. */ while (!STAILQ_EMPTY(&ic->ic_to_send)) { pdu = STAILQ_FIRST(&ic->ic_to_send); STAILQ_REMOVE_HEAD(&ic->ic_to_send, ip_next); icl_pdu_free(pdu); } KASSERT(STAILQ_EMPTY(&ic->ic_to_send), ("destroying session with non-empty send queue")); #ifdef DIAGNOSTIC KASSERT(ic->ic_outstanding_pdus == 0, ("destroying session with %d outstanding PDUs", ic->ic_outstanding_pdus)); #endif ICL_CONN_UNLOCK(ic); } bool icl_conn_connected(struct icl_conn *ic) { ICL_CONN_LOCK_ASSERT_NOT(ic); ICL_CONN_LOCK(ic); if (ic->ic_socket == NULL) { ICL_CONN_UNLOCK(ic); return (false); } if (ic->ic_socket->so_error != 0) { ICL_CONN_UNLOCK(ic); return (false); } ICL_CONN_UNLOCK(ic); return (true); } #ifdef ICL_KERNEL_PROXY int icl_conn_handoff_sock(struct icl_conn *ic, struct socket *so) { int error; ICL_CONN_LOCK_ASSERT_NOT(ic); if (so->so_type != SOCK_STREAM) return (EINVAL); ICL_CONN_LOCK(ic); if (ic->ic_socket != NULL) { ICL_CONN_UNLOCK(ic); return (EBUSY); } ic->ic_socket = so; ICL_CONN_UNLOCK(ic); error = icl_conn_start(ic); return (error); } #endif /* ICL_KERNEL_PROXY */ static int icl_unload(void) { if (icl_ncons != 0) return (EBUSY); uma_zdestroy(icl_conn_zone); uma_zdestroy(icl_pdu_zone); return (0); } static void icl_load(void) { icl_conn_zone = uma_zcreate("icl_conn", sizeof(struct icl_conn), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); icl_pdu_zone = uma_zcreate("icl_pdu", sizeof(struct icl_pdu), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); refcount_init(&icl_ncons, 0); } static int icl_modevent(module_t mod, int what, void *arg) { switch (what) { case MOD_LOAD: icl_load(); return (0); 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);