// SPDX-License-Identifier: GPL-2.0 #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_BLOCK #include #endif /* CONFIG_BLOCK */ #include #include #include #include #include #include #include #include /* * Ceph uses the messenger to exchange ceph_msg messages with other * hosts in the system. The messenger provides ordered and reliable * delivery. We tolerate TCP disconnects by reconnecting (with * exponential backoff) in the case of a fault (disconnection, bad * crc, protocol error). Acks allow sent messages to be discarded by * the sender. */ /* * We track the state of the socket on a given connection using * values defined below. The transition to a new socket state is * handled by a function which verifies we aren't coming from an * unexpected state. * * -------- * | NEW* | transient initial state * -------- * | con_sock_state_init() * v * ---------- * | CLOSED | initialized, but no socket (and no * ---------- TCP connection) * ^ \ * | \ con_sock_state_connecting() * | ---------------------- * | \ * + con_sock_state_closed() \ * |+--------------------------- \ * | \ \ \ * | ----------- \ \ * | | CLOSING | socket event; \ \ * | ----------- await close \ \ * | ^ \ | * | | \ | * | + con_sock_state_closing() \ | * | / \ | | * | / --------------- | | * | / \ v v * | / -------------- * | / -----------------| CONNECTING | socket created, TCP * | | / -------------- connect initiated * | | | con_sock_state_connected() * | | v * ------------- * | CONNECTED | TCP connection established * ------------- * * State values for ceph_connection->sock_state; NEW is assumed to be 0. */ #define CON_SOCK_STATE_NEW 0 /* -> CLOSED */ #define CON_SOCK_STATE_CLOSED 1 /* -> CONNECTING */ #define CON_SOCK_STATE_CONNECTING 2 /* -> CONNECTED or -> CLOSING */ #define CON_SOCK_STATE_CONNECTED 3 /* -> CLOSING or -> CLOSED */ #define CON_SOCK_STATE_CLOSING 4 /* -> CLOSED */ /* * connection states */ #define CON_STATE_CLOSED 1 /* -> PREOPEN */ #define CON_STATE_PREOPEN 2 /* -> CONNECTING, CLOSED */ #define CON_STATE_CONNECTING 3 /* -> NEGOTIATING, CLOSED */ #define CON_STATE_NEGOTIATING 4 /* -> OPEN, CLOSED */ #define CON_STATE_OPEN 5 /* -> STANDBY, CLOSED */ #define CON_STATE_STANDBY 6 /* -> PREOPEN, CLOSED */ /* * ceph_connection flag bits */ #define CON_FLAG_LOSSYTX 0 /* we can close channel or drop * messages on errors */ #define CON_FLAG_KEEPALIVE_PENDING 1 /* we need to send a keepalive */ #define CON_FLAG_WRITE_PENDING 2 /* we have data ready to send */ #define CON_FLAG_SOCK_CLOSED 3 /* socket state changed to closed */ #define CON_FLAG_BACKOFF 4 /* need to retry queuing delayed work */ static bool con_flag_valid(unsigned long con_flag) { switch (con_flag) { case CON_FLAG_LOSSYTX: case CON_FLAG_KEEPALIVE_PENDING: case CON_FLAG_WRITE_PENDING: case CON_FLAG_SOCK_CLOSED: case CON_FLAG_BACKOFF: return true; default: return false; } } static void con_flag_clear(struct ceph_connection *con, unsigned long con_flag) { BUG_ON(!con_flag_valid(con_flag)); clear_bit(con_flag, &con->flags); } static void con_flag_set(struct ceph_connection *con, unsigned long con_flag) { BUG_ON(!con_flag_valid(con_flag)); set_bit(con_flag, &con->flags); } static bool con_flag_test(struct ceph_connection *con, unsigned long con_flag) { BUG_ON(!con_flag_valid(con_flag)); return test_bit(con_flag, &con->flags); } static bool con_flag_test_and_clear(struct ceph_connection *con, unsigned long con_flag) { BUG_ON(!con_flag_valid(con_flag)); return test_and_clear_bit(con_flag, &con->flags); } static bool con_flag_test_and_set(struct ceph_connection *con, unsigned long con_flag) { BUG_ON(!con_flag_valid(con_flag)); return test_and_set_bit(con_flag, &con->flags); } /* Slab caches for frequently-allocated structures */ static struct kmem_cache *ceph_msg_cache; static struct kmem_cache *ceph_msg_data_cache; /* static tag bytes (protocol control messages) */ static char tag_msg = CEPH_MSGR_TAG_MSG; static char tag_ack = CEPH_MSGR_TAG_ACK; static char tag_keepalive = CEPH_MSGR_TAG_KEEPALIVE; static char tag_keepalive2 = CEPH_MSGR_TAG_KEEPALIVE2; #ifdef CONFIG_LOCKDEP static struct lock_class_key socket_class; #endif static void queue_con(struct ceph_connection *con); static void cancel_con(struct ceph_connection *con); static void ceph_con_workfn(struct work_struct *); static void con_fault(struct ceph_connection *con); /* * Nicely render a sockaddr as a string. An array of formatted * strings is used, to approximate reentrancy. */ #define ADDR_STR_COUNT_LOG 5 /* log2(# address strings in array) */ #define ADDR_STR_COUNT (1 << ADDR_STR_COUNT_LOG) #define ADDR_STR_COUNT_MASK (ADDR_STR_COUNT - 1) #define MAX_ADDR_STR_LEN 64 /* 54 is enough */ static char addr_str[ADDR_STR_COUNT][MAX_ADDR_STR_LEN]; static atomic_t addr_str_seq = ATOMIC_INIT(0); static struct page *zero_page; /* used in certain error cases */ const char *ceph_pr_addr(const struct sockaddr_storage *ss) { int i; char *s; struct sockaddr_in *in4 = (struct sockaddr_in *) ss; struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) ss; i = atomic_inc_return(&addr_str_seq) & ADDR_STR_COUNT_MASK; s = addr_str[i]; switch (ss->ss_family) { case AF_INET: snprintf(s, MAX_ADDR_STR_LEN, "%pI4:%hu", &in4->sin_addr, ntohs(in4->sin_port)); break; case AF_INET6: snprintf(s, MAX_ADDR_STR_LEN, "[%pI6c]:%hu", &in6->sin6_addr, ntohs(in6->sin6_port)); break; default: snprintf(s, MAX_ADDR_STR_LEN, "(unknown sockaddr family %hu)", ss->ss_family); } return s; } EXPORT_SYMBOL(ceph_pr_addr); static void encode_my_addr(struct ceph_messenger *msgr) { memcpy(&msgr->my_enc_addr, &msgr->inst.addr, sizeof(msgr->my_enc_addr)); ceph_encode_addr(&msgr->my_enc_addr); } /* * work queue for all reading and writing to/from the socket. */ static struct workqueue_struct *ceph_msgr_wq; static int ceph_msgr_slab_init(void) { BUG_ON(ceph_msg_cache); ceph_msg_cache = KMEM_CACHE(ceph_msg, 0); if (!ceph_msg_cache) return -ENOMEM; BUG_ON(ceph_msg_data_cache); ceph_msg_data_cache = KMEM_CACHE(ceph_msg_data, 0); if (ceph_msg_data_cache) return 0; kmem_cache_destroy(ceph_msg_cache); ceph_msg_cache = NULL; return -ENOMEM; } static void ceph_msgr_slab_exit(void) { BUG_ON(!ceph_msg_data_cache); kmem_cache_destroy(ceph_msg_data_cache); ceph_msg_data_cache = NULL; BUG_ON(!ceph_msg_cache); kmem_cache_destroy(ceph_msg_cache); ceph_msg_cache = NULL; } static void _ceph_msgr_exit(void) { if (ceph_msgr_wq) { destroy_workqueue(ceph_msgr_wq); ceph_msgr_wq = NULL; } BUG_ON(zero_page == NULL); put_page(zero_page); zero_page = NULL; ceph_msgr_slab_exit(); } int __init ceph_msgr_init(void) { if (ceph_msgr_slab_init()) return -ENOMEM; BUG_ON(zero_page != NULL); zero_page = ZERO_PAGE(0); get_page(zero_page); /* * The number of active work items is limited by the number of * connections, so leave @max_active at default. */ ceph_msgr_wq = alloc_workqueue("ceph-msgr", WQ_MEM_RECLAIM, 0); if (ceph_msgr_wq) return 0; pr_err("msgr_init failed to create workqueue\n"); _ceph_msgr_exit(); return -ENOMEM; } void ceph_msgr_exit(void) { BUG_ON(ceph_msgr_wq == NULL); _ceph_msgr_exit(); } void ceph_msgr_flush(void) { flush_workqueue(ceph_msgr_wq); } EXPORT_SYMBOL(ceph_msgr_flush); /* Connection socket state transition functions */ static void con_sock_state_init(struct ceph_connection *con) { int old_state; old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CLOSED); if (WARN_ON(old_state != CON_SOCK_STATE_NEW)) printk("%s: unexpected old state %d\n", __func__, old_state); dout("%s con %p sock %d -> %d\n", __func__, con, old_state, CON_SOCK_STATE_CLOSED); } static void con_sock_state_connecting(struct ceph_connection *con) { int old_state; old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CONNECTING); if (WARN_ON(old_state != CON_SOCK_STATE_CLOSED)) printk("%s: unexpected old state %d\n", __func__, old_state); dout("%s con %p sock %d -> %d\n", __func__, con, old_state, CON_SOCK_STATE_CONNECTING); } static void con_sock_state_connected(struct ceph_connection *con) { int old_state; old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CONNECTED); if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTING)) printk("%s: unexpected old state %d\n", __func__, old_state); dout("%s con %p sock %d -> %d\n", __func__, con, old_state, CON_SOCK_STATE_CONNECTED); } static void con_sock_state_closing(struct ceph_connection *con) { int old_state; old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CLOSING); if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTING && old_state != CON_SOCK_STATE_CONNECTED && old_state != CON_SOCK_STATE_CLOSING)) printk("%s: unexpected old state %d\n", __func__, old_state); dout("%s con %p sock %d -> %d\n", __func__, con, old_state, CON_SOCK_STATE_CLOSING); } static void con_sock_state_closed(struct ceph_connection *con) { int old_state; old_state = atomic_xchg(&con->sock_state, CON_SOCK_STATE_CLOSED); if (WARN_ON(old_state != CON_SOCK_STATE_CONNECTED && old_state != CON_SOCK_STATE_CLOSING && old_state != CON_SOCK_STATE_CONNECTING && old_state != CON_SOCK_STATE_CLOSED)) printk("%s: unexpected old state %d\n", __func__, old_state); dout("%s con %p sock %d -> %d\n", __func__, con, old_state, CON_SOCK_STATE_CLOSED); } /* * socket callback functions */ /* data available on socket, or listen socket received a connect */ static void ceph_sock_data_ready(struct sock *sk) { struct ceph_connection *con = sk->sk_user_data; if (atomic_read(&con->msgr->stopping)) { return; } if (sk->sk_state != TCP_CLOSE_WAIT) { dout("%s on %p state = %lu, queueing work\n", __func__, con, con->state); queue_con(con); } } /* socket has buffer space for writing */ static void ceph_sock_write_space(struct sock *sk) { struct ceph_connection *con = sk->sk_user_data; /* only queue to workqueue if there is data we want to write, * and there is sufficient space in the socket buffer to accept * more data. clear SOCK_NOSPACE so that ceph_sock_write_space() * doesn't get called again until try_write() fills the socket * buffer. See net/ipv4/tcp_input.c:tcp_check_space() * and net/core/stream.c:sk_stream_write_space(). */ if (con_flag_test(con, CON_FLAG_WRITE_PENDING)) { if (sk_stream_is_writeable(sk)) { dout("%s %p queueing write work\n", __func__, con); clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags); queue_con(con); } } else { dout("%s %p nothing to write\n", __func__, con); } } /* socket's state has changed */ static void ceph_sock_state_change(struct sock *sk) { struct ceph_connection *con = sk->sk_user_data; dout("%s %p state = %lu sk_state = %u\n", __func__, con, con->state, sk->sk_state); switch (sk->sk_state) { case TCP_CLOSE: dout("%s TCP_CLOSE\n", __func__); /* fall through */ case TCP_CLOSE_WAIT: dout("%s TCP_CLOSE_WAIT\n", __func__); con_sock_state_closing(con); con_flag_set(con, CON_FLAG_SOCK_CLOSED); queue_con(con); break; case TCP_ESTABLISHED: dout("%s TCP_ESTABLISHED\n", __func__); con_sock_state_connected(con); queue_con(con); break; default: /* Everything else is uninteresting */ break; } } /* * set up socket callbacks */ static void set_sock_callbacks(struct socket *sock, struct ceph_connection *con) { struct sock *sk = sock->sk; sk->sk_user_data = con; sk->sk_data_ready = ceph_sock_data_ready; sk->sk_write_space = ceph_sock_write_space; sk->sk_state_change = ceph_sock_state_change; } /* * socket helpers */ /* * initiate connection to a remote socket. */ static int ceph_tcp_connect(struct ceph_connection *con) { struct sockaddr_storage *paddr = &con->peer_addr.in_addr; struct socket *sock; unsigned int noio_flag; int ret; BUG_ON(con->sock); /* sock_create_kern() allocates with GFP_KERNEL */ noio_flag = memalloc_noio_save(); ret = sock_create_kern(read_pnet(&con->msgr->net), paddr->ss_family, SOCK_STREAM, IPPROTO_TCP, &sock); memalloc_noio_restore(noio_flag); if (ret) return ret; sock->sk->sk_allocation = GFP_NOFS; #ifdef CONFIG_LOCKDEP lockdep_set_class(&sock->sk->sk_lock, &socket_class); #endif set_sock_callbacks(sock, con); dout("connect %s\n", ceph_pr_addr(&con->peer_addr.in_addr)); con_sock_state_connecting(con); ret = sock->ops->connect(sock, (struct sockaddr *)paddr, sizeof(*paddr), O_NONBLOCK); if (ret == -EINPROGRESS) { dout("connect %s EINPROGRESS sk_state = %u\n", ceph_pr_addr(&con->peer_addr.in_addr), sock->sk->sk_state); } else if (ret < 0) { pr_err("connect %s error %d\n", ceph_pr_addr(&con->peer_addr.in_addr), ret); sock_release(sock); return ret; } if (ceph_test_opt(from_msgr(con->msgr), TCP_NODELAY)) { int optval = 1; ret = kernel_setsockopt(sock, SOL_TCP, TCP_NODELAY, (char *)&optval, sizeof(optval)); if (ret) pr_err("kernel_setsockopt(TCP_NODELAY) failed: %d", ret); } con->sock = sock; return 0; } /* * If @buf is NULL, discard up to @len bytes. */ static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len) { struct kvec iov = {buf, len}; struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL }; int r; if (!buf) msg.msg_flags |= MSG_TRUNC; iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &iov, 1, len); r = sock_recvmsg(sock, &msg, msg.msg_flags); if (r == -EAGAIN) r = 0; return r; } static int ceph_tcp_recvpage(struct socket *sock, struct page *page, int page_offset, size_t length) { struct bio_vec bvec = { .bv_page = page, .bv_offset = page_offset, .bv_len = length }; struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL }; int r; BUG_ON(page_offset + length > PAGE_SIZE); iov_iter_bvec(&msg.msg_iter, READ | ITER_BVEC, &bvec, 1, length); r = sock_recvmsg(sock, &msg, msg.msg_flags); if (r == -EAGAIN) r = 0; return r; } /* * write something. @more is true if caller will be sending more data * shortly. */ static int ceph_tcp_sendmsg(struct socket *sock, struct kvec *iov, size_t kvlen, size_t len, int more) { struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL }; int r; if (more) msg.msg_flags |= MSG_MORE; else msg.msg_flags |= MSG_EOR; /* superfluous, but what the hell */ r = kernel_sendmsg(sock, &msg, iov, kvlen, len); if (r == -EAGAIN) r = 0; return r; } static int __ceph_tcp_sendpage(struct socket *sock, struct page *page, int offset, size_t size, bool more) { int flags = MSG_DONTWAIT | MSG_NOSIGNAL | (more ? MSG_MORE : MSG_EOR); int ret; ret = kernel_sendpage(sock, page, offset, size, flags); if (ret == -EAGAIN) ret = 0; return ret; } static int ceph_tcp_sendpage(struct socket *sock, struct page *page, int offset, size_t size, bool more) { struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL }; struct bio_vec bvec; int ret; /* * sendpage cannot properly handle pages with page_count == 0, * we need to fall back to sendmsg if that's the case. * * Same goes for slab pages: skb_can_coalesce() allows * coalescing neighboring slab objects into a single frag which * triggers one of hardened usercopy checks. */ if (page_count(page) >= 1 && !PageSlab(page)) return __ceph_tcp_sendpage(sock, page, offset, size, more); bvec.bv_page = page; bvec.bv_offset = offset; bvec.bv_len = size; if (more) msg.msg_flags |= MSG_MORE; else msg.msg_flags |= MSG_EOR; /* superfluous, but what the hell */ iov_iter_bvec(&msg.msg_iter, WRITE | ITER_BVEC, &bvec, 1, size); ret = sock_sendmsg(sock, &msg); if (ret == -EAGAIN) ret = 0; return ret; } /* * Shutdown/close the socket for the given connection. */ static int con_close_socket(struct ceph_connection *con) { int rc = 0; dout("con_close_socket on %p sock %p\n", con, con->sock); if (con->sock) { rc = con->sock->ops->shutdown(con->sock, SHUT_RDWR); sock_release(con->sock); con->sock = NULL; } /* * Forcibly clear the SOCK_CLOSED flag. It gets set * independent of the connection mutex, and we could have * received a socket close event before we had the chance to * shut the socket down. */ con_flag_clear(con, CON_FLAG_SOCK_CLOSED); con_sock_state_closed(con); return rc; } /* * Reset a connection. Discard all incoming and outgoing messages * and clear *_seq state. */ static void ceph_msg_remove(struct ceph_msg *msg) { list_del_init(&msg->list_head); ceph_msg_put(msg); } static void ceph_msg_remove_list(struct list_head *head) { while (!list_empty(head)) { struct ceph_msg *msg = list_first_entry(head, struct ceph_msg, list_head); ceph_msg_remove(msg); } } static void reset_connection(struct ceph_connection *con) { /* reset connection, out_queue, msg_ and connect_seq */ /* discard existing out_queue and msg_seq */ dout("reset_connection %p\n", con); ceph_msg_remove_list(&con->out_queue); ceph_msg_remove_list(&con->out_sent); if (con->in_msg) { BUG_ON(con->in_msg->con != con); ceph_msg_put(con->in_msg); con->in_msg = NULL; } con->connect_seq = 0; con->out_seq = 0; if (con->out_msg) { BUG_ON(con->out_msg->con != con); ceph_msg_put(con->out_msg); con->out_msg = NULL; } con->in_seq = 0; con->in_seq_acked = 0; con->out_skip = 0; } /* * mark a peer down. drop any open connections. */ void ceph_con_close(struct ceph_connection *con) { mutex_lock(&con->mutex); dout("con_close %p peer %s\n", con, ceph_pr_addr(&con->peer_addr.in_addr)); con->state = CON_STATE_CLOSED; con_flag_clear(con, CON_FLAG_LOSSYTX); /* so we retry next connect */ con_flag_clear(con, CON_FLAG_KEEPALIVE_PENDING); con_flag_clear(con, CON_FLAG_WRITE_PENDING); con_flag_clear(con, CON_FLAG_BACKOFF); reset_connection(con); con->peer_global_seq = 0; cancel_con(con); con_close_socket(con); mutex_unlock(&con->mutex); } EXPORT_SYMBOL(ceph_con_close); /* * Reopen a closed connection, with a new peer address. */ void ceph_con_open(struct ceph_connection *con, __u8 entity_type, __u64 entity_num, struct ceph_entity_addr *addr) { mutex_lock(&con->mutex); dout("con_open %p %s\n", con, ceph_pr_addr(&addr->in_addr)); WARN_ON(con->state != CON_STATE_CLOSED); con->state = CON_STATE_PREOPEN; con->peer_name.type = (__u8) entity_type; con->peer_name.num = cpu_to_le64(entity_num); memcpy(&con->peer_addr, addr, sizeof(*addr)); con->delay = 0; /* reset backoff memory */ mutex_unlock(&con->mutex); queue_con(con); } EXPORT_SYMBOL(ceph_con_open); /* * return true if this connection ever successfully opened */ bool ceph_con_opened(struct ceph_connection *con) { return con->connect_seq > 0; } /* * initialize a new connection. */ void ceph_con_init(struct ceph_connection *con, void *private, const struct ceph_connection_operations *ops, struct ceph_messenger *msgr) { dout("con_init %p\n", con); memset(con, 0, sizeof(*con)); con->private = private; con->ops = ops; con->msgr = msgr; con_sock_state_init(con); mutex_init(&con->mutex); INIT_LIST_HEAD(&con->out_queue); INIT_LIST_HEAD(&con->out_sent); INIT_DELAYED_WORK(&con->work, ceph_con_workfn); con->state = CON_STATE_CLOSED; } EXPORT_SYMBOL(ceph_con_init); /* * We maintain a global counter to order connection attempts. Get * a unique seq greater than @gt. */ static u32 get_global_seq(struct ceph_messenger *msgr, u32 gt) { u32 ret; spin_lock(&msgr->global_seq_lock); if (msgr->global_seq < gt) msgr->global_seq = gt; ret = ++msgr->global_seq; spin_unlock(&msgr->global_seq_lock); return ret; } static void con_out_kvec_reset(struct ceph_connection *con) { BUG_ON(con->out_skip); con->out_kvec_left = 0; con->out_kvec_bytes = 0; con->out_kvec_cur = &con->out_kvec[0]; } static void con_out_kvec_add(struct ceph_connection *con, size_t size, void *data) { int index = con->out_kvec_left; BUG_ON(con->out_skip); BUG_ON(index >= ARRAY_SIZE(con->out_kvec)); con->out_kvec[index].iov_len = size; con->out_kvec[index].iov_base = data; con->out_kvec_left++; con->out_kvec_bytes += size; } /* * Chop off a kvec from the end. Return residual number of bytes for * that kvec, i.e. how many bytes would have been written if the kvec * hadn't been nuked. */ static int con_out_kvec_skip(struct ceph_connection *con) { int off = con->out_kvec_cur - con->out_kvec; int skip = 0; if (con->out_kvec_bytes > 0) { skip = con->out_kvec[off + con->out_kvec_left - 1].iov_len; BUG_ON(con->out_kvec_bytes < skip); BUG_ON(!con->out_kvec_left); con->out_kvec_bytes -= skip; con->out_kvec_left--; } return skip; } #ifdef CONFIG_BLOCK /* * For a bio data item, a piece is whatever remains of the next * entry in the current bio iovec, or the first entry in the next * bio in the list. */ static void ceph_msg_data_bio_cursor_init(struct ceph_msg_data_cursor *cursor, size_t length) { struct ceph_msg_data *data = cursor->data; struct ceph_bio_iter *it = &cursor->bio_iter; cursor->resid = min_t(size_t, length, data->bio_length); *it = data->bio_pos; if (cursor->resid < it->iter.bi_size) it->iter.bi_size = cursor->resid; BUG_ON(cursor->resid < bio_iter_len(it->bio, it->iter)); cursor->last_piece = cursor->resid == bio_iter_len(it->bio, it->iter); } static struct page *ceph_msg_data_bio_next(struct ceph_msg_data_cursor *cursor, size_t *page_offset, size_t *length) { struct bio_vec bv = bio_iter_iovec(cursor->bio_iter.bio, cursor->bio_iter.iter); *page_offset = bv.bv_offset; *length = bv.bv_len; return bv.bv_page; } static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor, size_t bytes) { struct ceph_bio_iter *it = &cursor->bio_iter; BUG_ON(bytes > cursor->resid); BUG_ON(bytes > bio_iter_len(it->bio, it->iter)); cursor->resid -= bytes; bio_advance_iter(it->bio, &it->iter, bytes); if (!cursor->resid) { BUG_ON(!cursor->last_piece); return false; /* no more data */ } if (!bytes || (it->iter.bi_size && it->iter.bi_bvec_done)) return false; /* more bytes to process in this segment */ if (!it->iter.bi_size) { it->bio = it->bio->bi_next; it->iter = it->bio->bi_iter; if (cursor->resid < it->iter.bi_size) it->iter.bi_size = cursor->resid; } BUG_ON(cursor->last_piece); BUG_ON(cursor->resid < bio_iter_len(it->bio, it->iter)); cursor->last_piece = cursor->resid == bio_iter_len(it->bio, it->iter); return true; } #endif /* CONFIG_BLOCK */ static void ceph_msg_data_bvecs_cursor_init(struct ceph_msg_data_cursor *cursor, size_t length) { struct ceph_msg_data *data = cursor->data; struct bio_vec *bvecs = data->bvec_pos.bvecs; cursor->resid = min_t(size_t, length, data->bvec_pos.iter.bi_size); cursor->bvec_iter = data->bvec_pos.iter; cursor->bvec_iter.bi_size = cursor->resid; BUG_ON(cursor->resid < bvec_iter_len(bvecs, cursor->bvec_iter)); cursor->last_piece = cursor->resid == bvec_iter_len(bvecs, cursor->bvec_iter); } static struct page *ceph_msg_data_bvecs_next(struct ceph_msg_data_cursor *cursor, size_t *page_offset, size_t *length) { struct bio_vec bv = bvec_iter_bvec(cursor->data->bvec_pos.bvecs, cursor->bvec_iter); *page_offset = bv.bv_offset; *length = bv.bv_len; return bv.bv_page; } static bool ceph_msg_data_bvecs_advance(struct ceph_msg_data_cursor *cursor, size_t bytes) { struct bio_vec *bvecs = cursor->data->bvec_pos.bvecs; BUG_ON(bytes > cursor->resid); BUG_ON(bytes > bvec_iter_len(bvecs, cursor->bvec_iter)); cursor->resid -= bytes; bvec_iter_advance(bvecs, &cursor->bvec_iter, bytes); if (!cursor->resid) { BUG_ON(!cursor->last_piece); return false; /* no more data */ } if (!bytes || cursor->bvec_iter.bi_bvec_done) return false; /* more bytes to process in this segment */ BUG_ON(cursor->last_piece); BUG_ON(cursor->resid < bvec_iter_len(bvecs, cursor->bvec_iter)); cursor->last_piece = cursor->resid == bvec_iter_len(bvecs, cursor->bvec_iter); return true; } /* * For a page array, a piece comes from the first page in the array * that has not already been fully consumed. */ static void ceph_msg_data_pages_cursor_init(struct ceph_msg_data_cursor *cursor, size_t length) { struct ceph_msg_data *data = cursor->data; int page_count; BUG_ON(data->type != CEPH_MSG_DATA_PAGES); BUG_ON(!data->pages); BUG_ON(!data->length); cursor->resid = min(length, data->length); page_count = calc_pages_for(data->alignment, (u64)data->length); cursor->page_offset = data->alignment & ~PAGE_MASK; cursor->page_index = 0; BUG_ON(page_count > (int)USHRT_MAX); cursor->page_count = (unsigned short)page_count; BUG_ON(length > SIZE_MAX - cursor->page_offset); cursor->last_piece = cursor->page_offset + cursor->resid <= PAGE_SIZE; } static struct page * ceph_msg_data_pages_next(struct ceph_msg_data_cursor *cursor, size_t *page_offset, size_t *length) { struct ceph_msg_data *data = cursor->data; BUG_ON(data->type != CEPH_MSG_DATA_PAGES); BUG_ON(cursor->page_index >= cursor->page_count); BUG_ON(cursor->page_offset >= PAGE_SIZE); *page_offset = cursor->page_offset; if (cursor->last_piece) *length = cursor->resid; else *length = PAGE_SIZE - *page_offset; return data->pages[cursor->page_index]; } static bool ceph_msg_data_pages_advance(struct ceph_msg_data_cursor *cursor, size_t bytes) { BUG_ON(cursor->data->type != CEPH_MSG_DATA_PAGES); BUG_ON(cursor->page_offset + bytes > PAGE_SIZE); /* Advance the cursor page offset */ cursor->resid -= bytes; cursor->page_offset = (cursor->page_offset + bytes) & ~PAGE_MASK; if (!bytes || cursor->page_offset) return false; /* more bytes to process in the current page */ if (!cursor->resid) return false; /* no more data */ /* Move on to the next page; offset is already at 0 */ BUG_ON(cursor->page_index >= cursor->page_count); cursor->page_index++; cursor->last_piece = cursor->resid <= PAGE_SIZE; return true; } /* * For a pagelist, a piece is whatever remains to be consumed in the * first page in the list, or the front of the next page. */ static void ceph_msg_data_pagelist_cursor_init(struct ceph_msg_data_cursor *cursor, size_t length) { struct ceph_msg_data *data = cursor->data; struct ceph_pagelist *pagelist; struct page *page; BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST); pagelist = data->pagelist; BUG_ON(!pagelist); if (!length) return; /* pagelist can be assigned but empty */ BUG_ON(list_empty(&pagelist->head)); page = list_first_entry(&pagelist->head, struct page, lru); cursor->resid = min(length, pagelist->length); cursor->page = page; cursor->offset = 0; cursor->last_piece = cursor->resid <= PAGE_SIZE; } static struct page * ceph_msg_data_pagelist_next(struct ceph_msg_data_cursor *cursor, size_t *page_offset, size_t *length) { struct ceph_msg_data *data = cursor->data; struct ceph_pagelist *pagelist; BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST); pagelist = data->pagelist; BUG_ON(!pagelist); BUG_ON(!cursor->page); BUG_ON(cursor->offset + cursor->resid != pagelist->length); /* offset of first page in pagelist is always 0 */ *page_offset = cursor->offset & ~PAGE_MASK; if (cursor->last_piece) *length = cursor->resid; else *length = PAGE_SIZE - *page_offset; return cursor->page; } static bool ceph_msg_data_pagelist_advance(struct ceph_msg_data_cursor *cursor, size_t bytes) { struct ceph_msg_data *data = cursor->data; struct ceph_pagelist *pagelist; BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST); pagelist = data->pagelist; BUG_ON(!pagelist); BUG_ON(cursor->offset + cursor->resid != pagelist->length); BUG_ON((cursor->offset & ~PAGE_MASK) + bytes > PAGE_SIZE); /* Advance the cursor offset */ cursor->resid -= bytes; cursor->offset += bytes; /* offset of first page in pagelist is always 0 */ if (!bytes || cursor->offset & ~PAGE_MASK) return false; /* more bytes to process in the current page */ if (!cursor->resid) return false; /* no more data */ /* Move on to the next page */ BUG_ON(list_is_last(&cursor->page->lru, &pagelist->head)); cursor->page = list_next_entry(cursor->page, lru); cursor->last_piece = cursor->resid <= PAGE_SIZE; return true; } /* * Message data is handled (sent or received) in pieces, where each * piece resides on a single page. The network layer might not * consume an entire piece at once. A data item's cursor keeps * track of which piece is next to process and how much remains to * be processed in that piece. It also tracks whether the current * piece is the last one in the data item. */ static void __ceph_msg_data_cursor_init(struct ceph_msg_data_cursor *cursor) { size_t length = cursor->total_resid; switch (cursor->data->type) { case CEPH_MSG_DATA_PAGELIST: ceph_msg_data_pagelist_cursor_init(cursor, length); break; case CEPH_MSG_DATA_PAGES: ceph_msg_data_pages_cursor_init(cursor, length); break; #ifdef CONFIG_BLOCK case CEPH_MSG_DATA_BIO: ceph_msg_data_bio_cursor_init(cursor, length); break; #endif /* CONFIG_BLOCK */ case CEPH_MSG_DATA_BVECS: ceph_msg_data_bvecs_cursor_init(cursor, length); break; case CEPH_MSG_DATA_NONE: default: /* BUG(); */ break; } cursor->need_crc = true; } static void ceph_msg_data_cursor_init(struct ceph_msg *msg, size_t length) { struct ceph_msg_data_cursor *cursor = &msg->cursor; struct ceph_msg_data *data; BUG_ON(!length); BUG_ON(length > msg->data_length); BUG_ON(list_empty(&msg->data)); cursor->data_head = &msg->data; cursor->total_resid = length; data = list_first_entry(&msg->data, struct ceph_msg_data, links); cursor->data = data; __ceph_msg_data_cursor_init(cursor); } /* * Return the page containing the next piece to process for a given * data item, and supply the page offset and length of that piece. * Indicate whether this is the last piece in this data item. */ static struct page *ceph_msg_data_next(struct ceph_msg_data_cursor *cursor, size_t *page_offset, size_t *length, bool *last_piece) { struct page *page; switch (cursor->data->type) { case CEPH_MSG_DATA_PAGELIST: page = ceph_msg_data_pagelist_next(cursor, page_offset, length); break; case CEPH_MSG_DATA_PAGES: page = ceph_msg_data_pages_next(cursor, page_offset, length); break; #ifdef CONFIG_BLOCK case CEPH_MSG_DATA_BIO: page = ceph_msg_data_bio_next(cursor, page_offset, length); break; #endif /* CONFIG_BLOCK */ case CEPH_MSG_DATA_BVECS: page = ceph_msg_data_bvecs_next(cursor, page_offset, length); break; case CEPH_MSG_DATA_NONE: default: page = NULL; break; } BUG_ON(!page); BUG_ON(*page_offset + *length > PAGE_SIZE); BUG_ON(!*length); BUG_ON(*length > cursor->resid); if (last_piece) *last_piece = cursor->last_piece; return page; } /* * Returns true if the result moves the cursor on to the next piece * of the data item. */ static void ceph_msg_data_advance(struct ceph_msg_data_cursor *cursor, size_t bytes) { bool new_piece; BUG_ON(bytes > cursor->resid); switch (cursor->data->type) { case CEPH_MSG_DATA_PAGELIST: new_piece = ceph_msg_data_pagelist_advance(cursor, bytes); break; case CEPH_MSG_DATA_PAGES: new_piece = ceph_msg_data_pages_advance(cursor, bytes); break; #ifdef CONFIG_BLOCK case CEPH_MSG_DATA_BIO: new_piece = ceph_msg_data_bio_advance(cursor, bytes); break; #endif /* CONFIG_BLOCK */ case CEPH_MSG_DATA_BVECS: new_piece = ceph_msg_data_bvecs_advance(cursor, bytes); break; case CEPH_MSG_DATA_NONE: default: BUG(); break; } cursor->total_resid -= bytes; if (!cursor->resid && cursor->total_resid) { WARN_ON(!cursor->last_piece); BUG_ON(list_is_last(&cursor->data->links, cursor->data_head)); cursor->data = list_next_entry(cursor->data, links); __ceph_msg_data_cursor_init(cursor); new_piece = true; } cursor->need_crc = new_piece; } static size_t sizeof_footer(struct ceph_connection *con) { return (con->peer_features & CEPH_FEATURE_MSG_AUTH) ? sizeof(struct ceph_msg_footer) : sizeof(struct ceph_msg_footer_old); } static void prepare_message_data(struct ceph_msg *msg, u32 data_len) { BUG_ON(!msg); BUG_ON(!data_len); /* Initialize data cursor */ ceph_msg_data_cursor_init(msg, (size_t)data_len); } /* * Prepare footer for currently outgoing message, and finish things * off. Assumes out_kvec* are already valid.. we just add on to the end. */ static void prepare_write_message_footer(struct ceph_connection *con) { struct ceph_msg *m = con->out_msg; m->footer.flags |= CEPH_MSG_FOOTER_COMPLETE; dout("prepare_write_message_footer %p\n", con); con_out_kvec_add(con, sizeof_footer(con), &m->footer); if (con->peer_features & CEPH_FEATURE_MSG_AUTH) { if (con->ops->sign_message) con->ops->sign_message(m); else m->footer.sig = 0; } else { m->old_footer.flags = m->footer.flags; } con->out_more = m->more_to_follow; con->out_msg_done = true; } /* * Prepare headers for the next outgoing message. */ static void prepare_write_message(struct ceph_connection *con) { struct ceph_msg *m; u32 crc; con_out_kvec_reset(con); con->out_msg_done = false; /* Sneak an ack in there first? If we can get it into the same * TCP packet that's a good thing. */ if (con->in_seq > con->in_seq_acked) { con->in_seq_acked = con->in_seq; con_out_kvec_add(con, sizeof (tag_ack), &tag_ack); con->out_temp_ack = cpu_to_le64(con->in_seq_acked); con_out_kvec_add(con, sizeof (con->out_temp_ack), &con->out_temp_ack); } BUG_ON(list_empty(&con->out_queue)); m = list_first_entry(&con->out_queue, struct ceph_msg, list_head); con->out_msg = m; BUG_ON(m->con != con); /* put message on sent list */ ceph_msg_get(m); list_move_tail(&m->list_head, &con->out_sent); /* * only assign outgoing seq # if we haven't sent this message * yet. if it is requeued, resend with it's original seq. */ if (m->needs_out_seq) { m->hdr.seq = cpu_to_le64(++con->out_seq); m->needs_out_seq = false; if (con->ops->reencode_message) con->ops->reencode_message(m); } dout("prepare_write_message %p seq %lld type %d len %d+%d+%zd\n", m, con->out_seq, le16_to_cpu(m->hdr.type), le32_to_cpu(m->hdr.front_len), le32_to_cpu(m->hdr.middle_len), m->data_length); WARN_ON(m->front.iov_len != le32_to_cpu(m->hdr.front_len)); WARN_ON(m->data_length != le32_to_cpu(m->hdr.data_len)); /* tag + hdr + front + middle */ con_out_kvec_add(con, sizeof (tag_msg), &tag_msg); con_out_kvec_add(con, sizeof(con->out_hdr), &con->out_hdr); con_out_kvec_add(con, m->front.iov_len, m->front.iov_base); if (m->middle) con_out_kvec_add(con, m->middle->vec.iov_len, m->middle->vec.iov_base); /* fill in hdr crc and finalize hdr */ crc = crc32c(0, &m->hdr, offsetof(struct ceph_msg_header, crc)); con->out_msg->hdr.crc = cpu_to_le32(crc); memcpy(&con->out_hdr, &con->out_msg->hdr, sizeof(con->out_hdr)); /* fill in front and middle crc, footer */ crc = crc32c(0, m->front.iov_base, m->front.iov_len); con->out_msg->footer.front_crc = cpu_to_le32(crc); if (m->middle) { crc = crc32c(0, m->middle->vec.iov_base, m->middle->vec.iov_len); con->out_msg->footer.middle_crc = cpu_to_le32(crc); } else con->out_msg->footer.middle_crc = 0; dout("%s front_crc %u middle_crc %u\n", __func__, le32_to_cpu(con->out_msg->footer.front_crc), le32_to_cpu(con->out_msg->footer.middle_crc)); con->out_msg->footer.flags = 0; /* is there a data payload? */ con->out_msg->footer.data_crc = 0; if (m->data_length) { prepare_message_data(con->out_msg, m->data_length); con->out_more = 1; /* data + footer will follow */ } else { /* no, queue up footer too and be done */ prepare_write_message_footer(con); } con_flag_set(con, CON_FLAG_WRITE_PENDING); } /* * Prepare an ack. */ static void prepare_write_ack(struct ceph_connection *con) { dout("prepare_write_ack %p %llu -> %llu\n", con, con->in_seq_acked, con->in_seq); con->in_seq_acked = con->in_seq; con_out_kvec_reset(con); con_out_kvec_add(con, sizeof (tag_ack), &tag_ack); con->out_temp_ack = cpu_to_le64(con->in_seq_acked); con_out_kvec_add(con, sizeof (con->out_temp_ack), &con->out_temp_ack); con->out_more = 1; /* more will follow.. eventually.. */ con_flag_set(con, CON_FLAG_WRITE_PENDING); } /* * Prepare to share the seq during handshake */ static void prepare_write_seq(struct ceph_connection *con) { dout("prepare_write_seq %p %llu -> %llu\n", con, con->in_seq_acked, con->in_seq); con->in_seq_acked = con->in_seq; con_out_kvec_reset(con); con->out_temp_ack = cpu_to_le64(con->in_seq_acked); con_out_kvec_add(con, sizeof (con->out_temp_ack), &con->out_temp_ack); con_flag_set(con, CON_FLAG_WRITE_PENDING); } /* * Prepare to write keepalive byte. */ static void prepare_write_keepalive(struct ceph_connection *con) { dout("prepare_write_keepalive %p\n", con); con_out_kvec_reset(con); if (con->peer_features & CEPH_FEATURE_MSGR_KEEPALIVE2) { struct timespec64 now; ktime_get_real_ts64(&now); con_out_kvec_add(con, sizeof(tag_keepalive2), &tag_keepalive2); ceph_encode_timespec64(&con->out_temp_keepalive2, &now); con_out_kvec_add(con, sizeof(con->out_temp_keepalive2), &con->out_temp_keepalive2); } else { con_out_kvec_add(con, sizeof(tag_keepalive), &tag_keepalive); } con_flag_set(con, CON_FLAG_WRITE_PENDING); } /* * Connection negotiation. */ static int get_connect_authorizer(struct ceph_connection *con) { struct ceph_auth_handshake *auth; int auth_proto; if (!con->ops->get_authorizer) { con->auth = NULL; con->out_connect.authorizer_protocol = CEPH_AUTH_UNKNOWN; con->out_connect.authorizer_len = 0; return 0; } auth = con->ops->get_authorizer(con, &auth_proto, con->auth_retry); if (IS_ERR(auth)) return PTR_ERR(auth); con->auth = auth; con->out_connect.authorizer_protocol = cpu_to_le32(auth_proto); con->out_connect.authorizer_len = cpu_to_le32(auth->authorizer_buf_len); return 0; } /* * We connected to a peer and are saying hello. */ static void prepare_write_banner(struct ceph_connection *con) { con_out_kvec_add(con, strlen(CEPH_BANNER), CEPH_BANNER); con_out_kvec_add(con, sizeof (con->msgr->my_enc_addr), &con->msgr->my_enc_addr); con->out_more = 0; con_flag_set(con, CON_FLAG_WRITE_PENDING); } static void __prepare_write_connect(struct ceph_connection *con) { con_out_kvec_add(con, sizeof(con->out_connect), &con->out_connect); if (con->auth) con_out_kvec_add(con, con->auth->authorizer_buf_len, con->auth->authorizer_buf); con->out_more = 0; con_flag_set(con, CON_FLAG_WRITE_PENDING); } static int prepare_write_connect(struct ceph_connection *con) { unsigned int global_seq = get_global_seq(con->msgr, 0); int proto; int ret; switch (con->peer_name.type) { case CEPH_ENTITY_TYPE_MON: proto = CEPH_MONC_PROTOCOL; break; case CEPH_ENTITY_TYPE_OSD: proto = CEPH_OSDC_PROTOCOL; break; case CEPH_ENTITY_TYPE_MDS: proto = CEPH_MDSC_PROTOCOL; break; default: BUG(); } dout("prepare_write_connect %p cseq=%d gseq=%d proto=%d\n", con, con->connect_seq, global_seq, proto); con->out_connect.features = cpu_to_le64(from_msgr(con->msgr)->supported_features); con->out_connect.host_type = cpu_to_le32(CEPH_ENTITY_TYPE_CLIENT); con->out_connect.connect_seq = cpu_to_le32(con->connect_seq); con->out_connect.global_seq = cpu_to_le32(global_seq); con->out_connect.protocol_version = cpu_to_le32(proto); con->out_connect.flags = 0; ret = get_connect_authorizer(con); if (ret) return ret; __prepare_write_connect(con); return 0; } /* * write as much of pending kvecs to the socket as we can. * 1 -> done * 0 -> socket full, but more to do * <0 -> error */ static int write_partial_kvec(struct ceph_connection *con) { int ret; dout("write_partial_kvec %p %d left\n", con, con->out_kvec_bytes); while (con->out_kvec_bytes > 0) { ret = ceph_tcp_sendmsg(con->sock, con->out_kvec_cur, con->out_kvec_left, con->out_kvec_bytes, con->out_more); if (ret <= 0) goto out; con->out_kvec_bytes -= ret; if (con->out_kvec_bytes == 0) break; /* done */ /* account for full iov entries consumed */ while (ret >= con->out_kvec_cur->iov_len) { BUG_ON(!con->out_kvec_left); ret -= con->out_kvec_cur->iov_len; con->out_kvec_cur++; con->out_kvec_left--; } /* and for a partially-consumed entry */ if (ret) { con->out_kvec_cur->iov_len -= ret; con->out_kvec_cur->iov_base += ret; } } con->out_kvec_left = 0; ret = 1; out: dout("write_partial_kvec %p %d left in %d kvecs ret = %d\n", con, con->out_kvec_bytes, con->out_kvec_left, ret); return ret; /* done! */ } static u32 ceph_crc32c_page(u32 crc, struct page *page, unsigned int page_offset, unsigned int length) { char *kaddr; kaddr = kmap(page); BUG_ON(kaddr == NULL); crc = crc32c(crc, kaddr + page_offset, length); kunmap(page); return crc; } /* * Write as much message data payload as we can. If we finish, queue * up the footer. * 1 -> done, footer is now queued in out_kvec[]. * 0 -> socket full, but more to do * <0 -> error */ static int write_partial_message_data(struct ceph_connection *con) { struct ceph_msg *msg = con->out_msg; struct ceph_msg_data_cursor *cursor = &msg->cursor; bool do_datacrc = !ceph_test_opt(from_msgr(con->msgr), NOCRC); u32 crc; dout("%s %p msg %p\n", __func__, con, msg); if (list_empty(&msg->data)) return -EINVAL; /* * Iterate through each page that contains data to be * written, and send as much as possible for each. * * If we are calculating the data crc (the default), we will * need to map the page. If we have no pages, they have * been revoked, so use the zero page. */ crc = do_datacrc ? le32_to_cpu(msg->footer.data_crc) : 0; while (cursor->total_resid) { struct page *page; size_t page_offset; size_t length; bool last_piece; int ret; if (!cursor->resid) { ceph_msg_data_advance(cursor, 0); continue; } page = ceph_msg_data_next(cursor, &page_offset, &length, &last_piece); ret = ceph_tcp_sendpage(con->sock, page, page_offset, length, !last_piece); if (ret <= 0) { if (do_datacrc) msg->footer.data_crc = cpu_to_le32(crc); return ret; } if (do_datacrc && cursor->need_crc) crc = ceph_crc32c_page(crc, page, page_offset, length); ceph_msg_data_advance(cursor, (size_t)ret); } dout("%s %p msg %p done\n", __func__, con, msg); /* prepare and queue up footer, too */ if (do_datacrc) msg->footer.data_crc = cpu_to_le32(crc); else msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC; con_out_kvec_reset(con); prepare_write_message_footer(con); return 1; /* must return > 0 to indicate success */ } /* * write some zeros */ static int write_partial_skip(struct ceph_connection *con) { int ret; dout("%s %p %d left\n", __func__, con, con->out_skip); while (con->out_skip > 0) { size_t size = min(con->out_skip, (int) PAGE_SIZE); ret = ceph_tcp_sendpage(con->sock, zero_page, 0, size, true); if (ret <= 0) goto out; con->out_skip -= ret; } ret = 1; out: return ret; } /* * Prepare to read connection handshake, or an ack. */ static void prepare_read_banner(struct ceph_connection *con) { dout("prepare_read_banner %p\n", con); con->in_base_pos = 0; } static void prepare_read_connect(struct ceph_connection *con) { dout("prepare_read_connect %p\n", con); con->in_base_pos = 0; } static void prepare_read_ack(struct ceph_connection *con) { dout("prepare_read_ack %p\n", con); con->in_base_pos = 0; } static void prepare_read_seq(struct ceph_connection *con) { dout("prepare_read_seq %p\n", con); con->in_base_pos = 0; con->in_tag = CEPH_MSGR_TAG_SEQ; } static void prepare_read_tag(struct ceph_connection *con) { dout("prepare_read_tag %p\n", con); con->in_base_pos = 0; con->in_tag = CEPH_MSGR_TAG_READY; } static void prepare_read_keepalive_ack(struct ceph_connection *con) { dout("prepare_read_keepalive_ack %p\n", con); con->in_base_pos = 0; } /* * Prepare to read a message. */ static int prepare_read_message(struct ceph_connection *con) { dout("prepare_read_message %p\n", con); BUG_ON(con->in_msg != NULL); con->in_base_pos = 0; con->in_front_crc = con->in_middle_crc = con->in_data_crc = 0; return 0; } static int read_partial(struct ceph_connection *con, int end, int size, void *object) { while (con->in_base_pos < end) { int left = end - con->in_base_pos; int have = size - left; int ret = ceph_tcp_recvmsg(con->sock, object + have, left); if (ret <= 0) return ret; con->in_base_pos += ret; } return 1; } /* * Read all or part of the connect-side handshake on a new connection */ static int read_partial_banner(struct ceph_connection *con) { int size; int end; int ret; dout("read_partial_banner %p at %d\n", con, con->in_base_pos); /* peer's banner */ size = strlen(CEPH_BANNER); end = size; ret = read_partial(con, end, size, con->in_banner); if (ret <= 0) goto out; size = sizeof (con->actual_peer_addr); end += size; ret = read_partial(con, end, size, &con->actual_peer_addr); if (ret <= 0) goto out; size = sizeof (con->peer_addr_for_me); end += size; ret = read_partial(con, end, size, &con->peer_addr_for_me); if (ret <= 0) goto out; out: return ret; } static int read_partial_connect(struct ceph_connection *con) { int size; int end; int ret; dout("read_partial_connect %p at %d\n", con, con->in_base_pos); size = sizeof (con->in_reply); end = size; ret = read_partial(con, end, size, &con->in_reply); if (ret <= 0) goto out; if (con->auth) { size = le32_to_cpu(con->in_reply.authorizer_len); if (size > con->auth->authorizer_reply_buf_len) { pr_err("authorizer reply too big: %d > %zu\n", size, con->auth->authorizer_reply_buf_len); ret = -EINVAL; goto out; } end += size; ret = read_partial(con, end, size, con->auth->authorizer_reply_buf); if (ret <= 0) goto out; } dout("read_partial_connect %p tag %d, con_seq = %u, g_seq = %u\n", con, (int)con->in_reply.tag, le32_to_cpu(con->in_reply.connect_seq), le32_to_cpu(con->in_reply.global_seq)); out: return ret; } /* * Verify the hello banner looks okay. */ static int verify_hello(struct ceph_connection *con) { if (memcmp(con->in_banner, CEPH_BANNER, strlen(CEPH_BANNER))) { pr_err("connect to %s got bad banner\n", ceph_pr_addr(&con->peer_addr.in_addr)); con->error_msg = "protocol error, bad banner"; return -1; } return 0; } static bool addr_is_blank(struct sockaddr_storage *ss) { struct in_addr *addr = &((struct sockaddr_in *)ss)->sin_addr; struct in6_addr *addr6 = &((struct sockaddr_in6 *)ss)->sin6_addr; switch (ss->ss_family) { case AF_INET: return addr->s_addr == htonl(INADDR_ANY); case AF_INET6: return ipv6_addr_any(addr6); default: return true; } } static int addr_port(struct sockaddr_storage *ss) { switch (ss->ss_family) { case AF_INET: return ntohs(((struct sockaddr_in *)ss)->sin_port); case AF_INET6: return ntohs(((struct sockaddr_in6 *)ss)->sin6_port); } return 0; } static void addr_set_port(struct sockaddr_storage *ss, int p) { switch (ss->ss_family) { case AF_INET: ((struct sockaddr_in *)ss)->sin_port = htons(p); break; case AF_INET6: ((struct sockaddr_in6 *)ss)->sin6_port = htons(p); break; } } /* * Unlike other *_pton function semantics, zero indicates success. */ static int ceph_pton(const char *str, size_t len, struct sockaddr_storage *ss, char delim, const char **ipend) { struct sockaddr_in *in4 = (struct sockaddr_in *) ss; struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) ss; memset(ss, 0, sizeof(*ss)); if (in4_pton(str, len, (u8 *)&in4->sin_addr.s_addr, delim, ipend)) { ss->ss_family = AF_INET; return 0; } if (in6_pton(str, len, (u8 *)&in6->sin6_addr.s6_addr, delim, ipend)) { ss->ss_family = AF_INET6; return 0; } return -EINVAL; } /* * Extract hostname string and resolve using kernel DNS facility. */ #ifdef CONFIG_CEPH_LIB_USE_DNS_RESOLVER static int ceph_dns_resolve_name(const char *name, size_t namelen, struct sockaddr_storage *ss, char delim, const char **ipend) { const char *end, *delim_p; char *colon_p, *ip_addr = NULL; int ip_len, ret; /* * The end of the hostname occurs immediately preceding the delimiter or * the port marker (':') where the delimiter takes precedence. */ delim_p = memchr(name, delim, namelen); colon_p = memchr(name, ':', namelen); if (delim_p && colon_p) end = delim_p < colon_p ? delim_p : colon_p; else if (!delim_p && colon_p) end = colon_p; else { end = delim_p; if (!end) /* case: hostname:/ */ end = name + namelen; } if (end <= name) return -EINVAL; /* do dns_resolve upcall */ ip_len = dns_query(NULL, name, end - name, NULL, &ip_addr, NULL); if (ip_len > 0) ret = ceph_pton(ip_addr, ip_len, ss, -1, NULL); else ret = -ESRCH; kfree(ip_addr); *ipend = end; pr_info("resolve '%.*s' (ret=%d): %s\n", (int)(end - name), name, ret, ret ? "failed" : ceph_pr_addr(ss)); return ret; } #else static inline int ceph_dns_resolve_name(const char *name, size_t namelen, struct sockaddr_storage *ss, char delim, const char **ipend) { return -EINVAL; } #endif /* * Parse a server name (IP or hostname). If a valid IP address is not found * then try to extract a hostname to resolve using userspace DNS upcall. */ static int ceph_parse_server_name(const char *name, size_t namelen, struct sockaddr_storage *ss, char delim, const char **ipend) { int ret; ret = ceph_pton(name, namelen, ss, delim, ipend); if (ret) ret = ceph_dns_resolve_name(name, namelen, ss, delim, ipend); return ret; } /* * Parse an ip[:port] list into an addr array. Use the default * monitor port if a port isn't specified. */ int ceph_parse_ips(const char *c, const char *end, struct ceph_entity_addr *addr, int max_count, int *count) { int i, ret = -EINVAL; const char *p = c; dout("parse_ips on '%.*s'\n", (int)(end-c), c); for (i = 0; i < max_count; i++) { const char *ipend; struct sockaddr_storage *ss = &addr[i].in_addr; int port; char delim = ','; if (*p == '[') { delim = ']'; p++; } ret = ceph_parse_server_name(p, end - p, ss, delim, &ipend); if (ret) goto bad; ret = -EINVAL; p = ipend; if (delim == ']') { if (*p != ']') { dout("missing matching ']'\n"); goto bad; } p++; } /* port? */ if (p < end && *p == ':') { port = 0; p++; while (p < end && *p >= '0' && *p <= '9') { port = (port * 10) + (*p - '0'); p++; } if (port == 0) port = CEPH_MON_PORT; else if (port > 65535) goto bad; } else { port = CEPH_MON_PORT; } addr_set_port(ss, port); dout("parse_ips got %s\n", ceph_pr_addr(ss)); if (p == end) break; if (*p != ',') goto bad; p++; } if (p != end) goto bad; if (count) *count = i + 1; return 0; bad: pr_err("parse_ips bad ip '%.*s'\n", (int)(end - c), c); return ret; } EXPORT_SYMBOL(ceph_parse_ips); static int process_banner(struct ceph_connection *con) { dout("process_banner on %p\n", con); if (verify_hello(con) < 0) return -1; ceph_decode_addr(&con->actual_peer_addr); ceph_decode_addr(&con->peer_addr_for_me); /* * Make sure the other end is who we wanted. note that the other * end may not yet know their ip address, so if it's 0.0.0.0, give * them the benefit of the doubt. */ if (memcmp(&con->peer_addr, &con->actual_peer_addr, sizeof(con->peer_addr)) != 0 && !(addr_is_blank(&con->actual_peer_addr.in_addr) && con->actual_peer_addr.nonce == con->peer_addr.nonce)) { pr_warn("wrong peer, want %s/%d, got %s/%d\n", ceph_pr_addr(&con->peer_addr.in_addr), (int)le32_to_cpu(con->peer_addr.nonce), ceph_pr_addr(&con->actual_peer_addr.in_addr), (int)le32_to_cpu(con->actual_peer_addr.nonce)); con->error_msg = "wrong peer at address"; return -1; } /* * did we learn our address? */ if (addr_is_blank(&con->msgr->inst.addr.in_addr)) { int port = addr_port(&con->msgr->inst.addr.in_addr); memcpy(&con->msgr->inst.addr.in_addr, &con->peer_addr_for_me.in_addr, sizeof(con->peer_addr_for_me.in_addr)); addr_set_port(&con->msgr->inst.addr.in_addr, port); encode_my_addr(con->msgr); dout("process_banner learned my addr is %s\n", ceph_pr_addr(&con->msgr->inst.addr.in_addr)); } return 0; } static int process_connect(struct ceph_connection *con) { u64 sup_feat = from_msgr(con->msgr)->supported_features; u64 req_feat = from_msgr(con->msgr)->required_features; u64 server_feat = le64_to_cpu(con->in_reply.features); int ret; dout("process_connect on %p tag %d\n", con, (int)con->in_tag); if (con->auth) { int len = le32_to_cpu(con->in_reply.authorizer_len); /* * Any connection that defines ->get_authorizer() * should also define ->add_authorizer_challenge() and * ->verify_authorizer_reply(). * * See get_connect_authorizer(). */ if (con->in_reply.tag == CEPH_MSGR_TAG_CHALLENGE_AUTHORIZER) { ret = con->ops->add_authorizer_challenge( con, con->auth->authorizer_reply_buf, len); if (ret < 0) return ret; con_out_kvec_reset(con); __prepare_write_connect(con); prepare_read_connect(con); return 0; } if (len) { ret = con->ops->verify_authorizer_reply(con); if (ret < 0) { con->error_msg = "bad authorize reply"; return ret; } } } switch (con->in_reply.tag) { case CEPH_MSGR_TAG_FEATURES: pr_err("%s%lld %s feature set mismatch," " my %llx < server's %llx, missing %llx\n", ENTITY_NAME(con->peer_name), ceph_pr_addr(&con->peer_addr.in_addr), sup_feat, server_feat, server_feat & ~sup_feat); con->error_msg = "missing required protocol features"; reset_connection(con); return -1; case CEPH_MSGR_TAG_BADPROTOVER: pr_err("%s%lld %s protocol version mismatch," " my %d != server's %d\n", ENTITY_NAME(con->peer_name), ceph_pr_addr(&con->peer_addr.in_addr), le32_to_cpu(con->out_connect.protocol_version), le32_to_cpu(con->in_reply.protocol_version)); con->error_msg = "protocol version mismatch"; reset_connection(con); return -1; case CEPH_MSGR_TAG_BADAUTHORIZER: con->auth_retry++; dout("process_connect %p got BADAUTHORIZER attempt %d\n", con, con->auth_retry); if (con->auth_retry == 2) { con->error_msg = "connect authorization failure"; return -1; } con_out_kvec_reset(con); ret = prepare_write_connect(con); if (ret < 0) return ret; prepare_read_connect(con); break; case CEPH_MSGR_TAG_RESETSESSION: /* * If we connected with a large connect_seq but the peer * has no record of a session with us (no connection, or * connect_seq == 0), they will send RESETSESION to indicate * that they must have reset their session, and may have * dropped messages. */ dout("process_connect got RESET peer seq %u\n", le32_to_cpu(con->in_reply.connect_seq)); pr_err("%s%lld %s connection reset\n", ENTITY_NAME(con->peer_name), ceph_pr_addr(&con->peer_addr.in_addr)); reset_connection(con); con_out_kvec_reset(con); ret = prepare_write_connect(con); if (ret < 0) return ret; prepare_read_connect(con); /* Tell ceph about it. */ mutex_unlock(&con->mutex); pr_info("reset on %s%lld\n", ENTITY_NAME(con->peer_name)); if (con->ops->peer_reset) con->ops->peer_reset(con); mutex_lock(&con->mutex); if (con->state != CON_STATE_NEGOTIATING) return -EAGAIN; break; case CEPH_MSGR_TAG_RETRY_SESSION: /* * If we sent a smaller connect_seq than the peer has, try * again with a larger value. */ dout("process_connect got RETRY_SESSION my seq %u, peer %u\n", le32_to_cpu(con->out_connect.connect_seq), le32_to_cpu(con->in_reply.connect_seq)); con->connect_seq = le32_to_cpu(con->in_reply.connect_seq); con_out_kvec_reset(con); ret = prepare_write_connect(con); if (ret < 0) return ret; prepare_read_connect(con); break; case CEPH_MSGR_TAG_RETRY_GLOBAL: /* * If we sent a smaller global_seq than the peer has, try * again with a larger value. */ dout("process_connect got RETRY_GLOBAL my %u peer_gseq %u\n", con->peer_global_seq, le32_to_cpu(con->in_reply.global_seq)); get_global_seq(con->msgr, le32_to_cpu(con->in_reply.global_seq)); con_out_kvec_reset(con); ret = prepare_write_connect(con); if (ret < 0) return ret; prepare_read_connect(con); break; case CEPH_MSGR_TAG_SEQ: case CEPH_MSGR_TAG_READY: if (req_feat & ~server_feat) { pr_err("%s%lld %s protocol feature mismatch," " my required %llx > server's %llx, need %llx\n", ENTITY_NAME(con->peer_name), ceph_pr_addr(&con->peer_addr.in_addr), req_feat, server_feat, req_feat & ~server_feat); con->error_msg = "missing required protocol features"; reset_connection(con); return -1; } WARN_ON(con->state != CON_STATE_NEGOTIATING); con->state = CON_STATE_OPEN; con->auth_retry = 0; /* we authenticated; clear flag */ con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq); con->connect_seq++; con->peer_features = server_feat; dout("process_connect got READY gseq %d cseq %d (%d)\n", con->peer_global_seq, le32_to_cpu(con->in_reply.connect_seq), con->connect_seq); WARN_ON(con->connect_seq != le32_to_cpu(con->in_reply.connect_seq)); if (con->in_reply.flags & CEPH_MSG_CONNECT_LOSSY) con_flag_set(con, CON_FLAG_LOSSYTX); con->delay = 0; /* reset backoff memory */ if (con->in_reply.tag == CEPH_MSGR_TAG_SEQ) { prepare_write_seq(con); prepare_read_seq(con); } else { prepare_read_tag(con); } break; case CEPH_MSGR_TAG_WAIT: /* * If there is a connection race (we are opening * connections to each other), one of us may just have * to WAIT. This shouldn't happen if we are the * client. */ con->error_msg = "protocol error, got WAIT as client"; return -1; default: con->error_msg = "protocol error, garbage tag during connect"; return -1; } return 0; } /* * read (part of) an ack */ static int read_partial_ack(struct ceph_connection *con) { int size = sizeof (con->in_temp_ack); int end = size; return read_partial(con, end, size, &con->in_temp_ack); } /* * We can finally discard anything that's been acked. */ static void process_ack(struct ceph_connection *con) { struct ceph_msg *m; u64 ack = le64_to_cpu(con->in_temp_ack); u64 seq; bool reconnect = (con->in_tag == CEPH_MSGR_TAG_SEQ); struct list_head *list = reconnect ? &con->out_queue : &con->out_sent; /* * In the reconnect case, con_fault() has requeued messages * in out_sent. We should cleanup old messages according to * the reconnect seq. */ while (!list_empty(list)) { m = list_first_entry(list, struct ceph_msg, list_head); if (reconnect && m->needs_out_seq) break; seq = le64_to_cpu(m->hdr.seq); if (seq > ack) break; dout("got ack for seq %llu type %d at %p\n", seq, le16_to_cpu(m->hdr.type), m); m->ack_stamp = jiffies; ceph_msg_remove(m); } prepare_read_tag(con); } static int read_partial_message_section(struct ceph_connection *con, struct kvec *section, unsigned int sec_len, u32 *crc) { int ret, left; BUG_ON(!section); while (section->iov_len < sec_len) { BUG_ON(section->iov_base == NULL); left = sec_len - section->iov_len; ret = ceph_tcp_recvmsg(con->sock, (char *)section->iov_base + section->iov_len, left); if (ret <= 0) return ret; section->iov_len += ret; } if (section->iov_len == sec_len) *crc = crc32c(0, section->iov_base, section->iov_len); return 1; } static int read_partial_msg_data(struct ceph_connection *con) { struct ceph_msg *msg = con->in_msg; struct ceph_msg_data_cursor *cursor = &msg->cursor; bool do_datacrc = !ceph_test_opt(from_msgr(con->msgr), NOCRC); struct page *page; size_t page_offset; size_t length; u32 crc = 0; int ret; BUG_ON(!msg); if (list_empty(&msg->data)) return -EIO; if (do_datacrc) crc = con->in_data_crc; while (cursor->total_resid) { if (!cursor->resid) { ceph_msg_data_advance(cursor, 0); continue; } page = ceph_msg_data_next(cursor, &page_offset, &length, NULL); ret = ceph_tcp_recvpage(con->sock, page, page_offset, length); if (ret <= 0) { if (do_datacrc) con->in_data_crc = crc; return ret; } if (do_datacrc) crc = ceph_crc32c_page(crc, page, page_offset, ret); ceph_msg_data_advance(cursor, (size_t)ret); } if (do_datacrc) con->in_data_crc = crc; return 1; /* must return > 0 to indicate success */ } /* * read (part of) a message. */ static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip); static int read_partial_message(struct ceph_connection *con) { struct ceph_msg *m = con->in_msg; int size; int end; int ret; unsigned int front_len, middle_len, data_len; bool do_datacrc = !ceph_test_opt(from_msgr(con->msgr), NOCRC); bool need_sign = (con->peer_features & CEPH_FEATURE_MSG_AUTH); u64 seq; u32 crc; dout("read_partial_message con %p msg %p\n", con, m); /* header */ size = sizeof (con->in_hdr); end = size; ret = read_partial(con, end, size, &con->in_hdr); if (ret <= 0) return ret; crc = crc32c(0, &con->in_hdr, offsetof(struct ceph_msg_header, crc)); if (cpu_to_le32(crc) != con->in_hdr.crc) { pr_err("read_partial_message bad hdr crc %u != expected %u\n", crc, con->in_hdr.crc); return -EBADMSG; } front_len = le32_to_cpu(con->in_hdr.front_len); if (front_len > CEPH_MSG_MAX_FRONT_LEN) return -EIO; middle_len = le32_to_cpu(con->in_hdr.middle_len); if (middle_len > CEPH_MSG_MAX_MIDDLE_LEN) return -EIO; data_len = le32_to_cpu(con->in_hdr.data_len); if (data_len > CEPH_MSG_MAX_DATA_LEN) return -EIO; /* verify seq# */ seq = le64_to_cpu(con->in_hdr.seq); if ((s64)seq - (s64)con->in_seq < 1) { pr_info("skipping %s%lld %s seq %lld expected %lld\n", ENTITY_NAME(con->peer_name), ceph_pr_addr(&con->peer_addr.in_addr), seq, con->in_seq + 1); con->in_base_pos = -front_len - middle_len - data_len - sizeof_footer(con); con->in_tag = CEPH_MSGR_TAG_READY; return 1; } else if ((s64)seq - (s64)con->in_seq > 1) { pr_err("read_partial_message bad seq %lld expected %lld\n", seq, con->in_seq + 1); con->error_msg = "bad message sequence # for incoming message"; return -EBADE; } /* allocate message? */ if (!con->in_msg) { int skip = 0; dout("got hdr type %d front %d data %d\n", con->in_hdr.type, front_len, data_len); ret = ceph_con_in_msg_alloc(con, &skip); if (ret < 0) return ret; BUG_ON(!con->in_msg ^ skip); if (skip) { /* skip this message */ dout("alloc_msg said skip message\n"); con->in_base_pos = -front_len - middle_len - data_len - sizeof_footer(con); con->in_tag = CEPH_MSGR_TAG_READY; con->in_seq++; return 1; } BUG_ON(!con->in_msg); BUG_ON(con->in_msg->con != con); m = con->in_msg; m->front.iov_len = 0; /* haven't read it yet */ if (m->middle) m->middle->vec.iov_len = 0; /* prepare for data payload, if any */ if (data_len) prepare_message_data(con->in_msg, data_len); } /* front */ ret = read_partial_message_section(con, &m->front, front_len, &con->in_front_crc); if (ret <= 0) return ret; /* middle */ if (m->middle) { ret = read_partial_message_section(con, &m->middle->vec, middle_len, &con->in_middle_crc); if (ret <= 0) return ret; } /* (page) data */ if (data_len) { ret = read_partial_msg_data(con); if (ret <= 0) return ret; } /* footer */ size = sizeof_footer(con); end += size; ret = read_partial(con, end, size, &m->footer); if (ret <= 0) return ret; if (!need_sign) { m->footer.flags = m->old_footer.flags; m->footer.sig = 0; } dout("read_partial_message got msg %p %d (%u) + %d (%u) + %d (%u)\n", m, front_len, m->footer.front_crc, middle_len, m->footer.middle_crc, data_len, m->footer.data_crc); /* crc ok? */ if (con->in_front_crc != le32_to_cpu(m->footer.front_crc)) { pr_err("read_partial_message %p front crc %u != exp. %u\n", m, con->in_front_crc, m->footer.front_crc); return -EBADMSG; } if (con->in_middle_crc != le32_to_cpu(m->footer.middle_crc)) { pr_err("read_partial_message %p middle crc %u != exp %u\n", m, con->in_middle_crc, m->footer.middle_crc); return -EBADMSG; } if (do_datacrc && (m->footer.flags & CEPH_MSG_FOOTER_NOCRC) == 0 && con->in_data_crc != le32_to_cpu(m->footer.data_crc)) { pr_err("read_partial_message %p data crc %u != exp. %u\n", m, con->in_data_crc, le32_to_cpu(m->footer.data_crc)); return -EBADMSG; } if (need_sign && con->ops->check_message_signature && con->ops->check_message_signature(m)) { pr_err("read_partial_message %p signature check failed\n", m); return -EBADMSG; } return 1; /* done! */ } /* * Process message. This happens in the worker thread. The callback should * be careful not to do anything that waits on other incoming messages or it * may deadlock. */ static void process_message(struct ceph_connection *con) { struct ceph_msg *msg = con->in_msg; BUG_ON(con->in_msg->con != con); con->in_msg = NULL; /* if first message, set peer_name */ if (con->peer_name.type == 0) con->peer_name = msg->hdr.src; con->in_seq++; mutex_unlock(&con->mutex); dout("===== %p %llu from %s%lld %d=%s len %d+%d (%u %u %u) =====\n", msg, le64_to_cpu(msg->hdr.seq), ENTITY_NAME(msg->hdr.src), le16_to_cpu(msg->hdr.type), ceph_msg_type_name(le16_to_cpu(msg->hdr.type)), le32_to_cpu(msg->hdr.front_len), le32_to_cpu(msg->hdr.data_len), con->in_front_crc, con->in_middle_crc, con->in_data_crc); con->ops->dispatch(con, msg); mutex_lock(&con->mutex); } static int read_keepalive_ack(struct ceph_connection *con) { struct ceph_timespec ceph_ts; size_t size = sizeof(ceph_ts); int ret = read_partial(con, size, size, &ceph_ts); if (ret <= 0) return ret; ceph_decode_timespec64(&con->last_keepalive_ack, &ceph_ts); prepare_read_tag(con); return 1; } /* * Write something to the socket. Called in a worker thread when the * socket appears to be writeable and we have something ready to send. */ static int try_write(struct ceph_connection *con) { int ret = 1; dout("try_write start %p state %lu\n", con, con->state); if (con->state != CON_STATE_PREOPEN && con->state != CON_STATE_CONNECTING && con->state != CON_STATE_NEGOTIATING && con->state != CON_STATE_OPEN) return 0; /* open the socket first? */ if (con->state == CON_STATE_PREOPEN) { BUG_ON(con->sock); con->state = CON_STATE_CONNECTING; con_out_kvec_reset(con); prepare_write_banner(con); prepare_read_banner(con); BUG_ON(con->in_msg); con->in_tag = CEPH_MSGR_TAG_READY; dout("try_write initiating connect on %p new state %lu\n", con, con->state); ret = ceph_tcp_connect(con); if (ret < 0) { con->error_msg = "connect error"; goto out; } } more: dout("try_write out_kvec_bytes %d\n", con->out_kvec_bytes); BUG_ON(!con->sock); /* kvec data queued? */ if (con->out_kvec_left) { ret = write_partial_kvec(con); if (ret <= 0) goto out; } if (con->out_skip) { ret = write_partial_skip(con); if (ret <= 0) goto out; } /* msg pages? */ if (con->out_msg) { if (con->out_msg_done) { ceph_msg_put(con->out_msg); con->out_msg = NULL; /* we're done with this one */ goto do_next; } ret = write_partial_message_data(con); if (ret == 1) goto more; /* we need to send the footer, too! */ if (ret == 0) goto out; if (ret < 0) { dout("try_write write_partial_message_data err %d\n", ret); goto out; } } do_next: if (con->state == CON_STATE_OPEN) { if (con_flag_test_and_clear(con, CON_FLAG_KEEPALIVE_PENDING)) { prepare_write_keepalive(con); goto more; } /* is anything else pending? */ if (!list_empty(&con->out_queue)) { prepare_write_message(con); goto more; } if (con->in_seq > con->in_seq_acked) { prepare_write_ack(con); goto more; } } /* Nothing to do! */ con_flag_clear(con, CON_FLAG_WRITE_PENDING); dout("try_write nothing else to write.\n"); ret = 0; out: dout("try_write done on %p ret %d\n", con, ret); return ret; } /* * Read what we can from the socket. */ static int try_read(struct ceph_connection *con) { int ret = -1; more: dout("try_read start on %p state %lu\n", con, con->state); if (con->state != CON_STATE_CONNECTING && con->state != CON_STATE_NEGOTIATING && con->state != CON_STATE_OPEN) return 0; BUG_ON(!con->sock); dout("try_read tag %d in_base_pos %d\n", (int)con->in_tag, con->in_base_pos); if (con->state == CON_STATE_CONNECTING) { dout("try_read connecting\n"); ret = read_partial_banner(con); if (ret <= 0) goto out; ret = process_banner(con); if (ret < 0) goto out; con->state = CON_STATE_NEGOTIATING; /* * Received banner is good, exchange connection info. * Do not reset out_kvec, as sending our banner raced * with receiving peer banner after connect completed. */ ret = prepare_write_connect(con); if (ret < 0) goto out; prepare_read_connect(con); /* Send connection info before awaiting response */ goto out; } if (con->state == CON_STATE_NEGOTIATING) { dout("try_read negotiating\n"); ret = read_partial_connect(con); if (ret <= 0) goto out; ret = process_connect(con); if (ret < 0) goto out; goto more; } WARN_ON(con->state != CON_STATE_OPEN); if (con->in_base_pos < 0) { /* * skipping + discarding content. */ ret = ceph_tcp_recvmsg(con->sock, NULL, -con->in_base_pos); if (ret <= 0) goto out; dout("skipped %d / %d bytes\n", ret, -con->in_base_pos); con->in_base_pos += ret; if (con->in_base_pos) goto more; } if (con->in_tag == CEPH_MSGR_TAG_READY) { /* * what's next? */ ret = ceph_tcp_recvmsg(con->sock, &con->in_tag, 1); if (ret <= 0) goto out; dout("try_read got tag %d\n", (int)con->in_tag); switch (con->in_tag) { case CEPH_MSGR_TAG_MSG: prepare_read_message(con); break; case CEPH_MSGR_TAG_ACK: prepare_read_ack(con); break; case CEPH_MSGR_TAG_KEEPALIVE2_ACK: prepare_read_keepalive_ack(con); break; case CEPH_MSGR_TAG_CLOSE: con_close_socket(con); con->state = CON_STATE_CLOSED; goto out; default: goto bad_tag; } } if (con->in_tag == CEPH_MSGR_TAG_MSG) { ret = read_partial_message(con); if (ret <= 0) { switch (ret) { case -EBADMSG: con->error_msg = "bad crc/signature"; /* fall through */ case -EBADE: ret = -EIO; break; case -EIO: con->error_msg = "io error"; break; } goto out; } if (con->in_tag == CEPH_MSGR_TAG_READY) goto more; process_message(con); if (con->state == CON_STATE_OPEN) prepare_read_tag(con); goto more; } if (con->in_tag == CEPH_MSGR_TAG_ACK || con->in_tag == CEPH_MSGR_TAG_SEQ) { /* * the final handshake seq exchange is semantically * equivalent to an ACK */ ret = read_partial_ack(con); if (ret <= 0) goto out; process_ack(con); goto more; } if (con->in_tag == CEPH_MSGR_TAG_KEEPALIVE2_ACK) { ret = read_keepalive_ack(con); if (ret <= 0) goto out; goto more; } out: dout("try_read done on %p ret %d\n", con, ret); return ret; bad_tag: pr_err("try_read bad con->in_tag = %d\n", (int)con->in_tag); con->error_msg = "protocol error, garbage tag"; ret = -1; goto out; } /* * Atomically queue work on a connection after the specified delay. * Bump @con reference to avoid races with connection teardown. * Returns 0 if work was queued, or an error code otherwise. */ static int queue_con_delay(struct ceph_connection *con, unsigned long delay) { if (!con->ops->get(con)) { dout("%s %p ref count 0\n", __func__, con); return -ENOENT; } if (!queue_delayed_work(ceph_msgr_wq, &con->work, delay)) { dout("%s %p - already queued\n", __func__, con); con->ops->put(con); return -EBUSY; } dout("%s %p %lu\n", __func__, con, delay); return 0; } static void queue_con(struct ceph_connection *con) { (void) queue_con_delay(con, 0); } static void cancel_con(struct ceph_connection *con) { if (cancel_delayed_work(&con->work)) { dout("%s %p\n", __func__, con); con->ops->put(con); } } static bool con_sock_closed(struct ceph_connection *con) { if (!con_flag_test_and_clear(con, CON_FLAG_SOCK_CLOSED)) return false; #define CASE(x) \ case CON_STATE_ ## x: \ con->error_msg = "socket closed (con state " #x ")"; \ break; switch (con->state) { CASE(CLOSED); CASE(PREOPEN); CASE(CONNECTING); CASE(NEGOTIATING); CASE(OPEN); CASE(STANDBY); default: pr_warn("%s con %p unrecognized state %lu\n", __func__, con, con->state); con->error_msg = "unrecognized con state"; BUG(); break; } #undef CASE return true; } static bool con_backoff(struct ceph_connection *con) { int ret; if (!con_flag_test_and_clear(con, CON_FLAG_BACKOFF)) return false; ret = queue_con_delay(con, round_jiffies_relative(con->delay)); if (ret) { dout("%s: con %p FAILED to back off %lu\n", __func__, con, con->delay); BUG_ON(ret == -ENOENT); con_flag_set(con, CON_FLAG_BACKOFF); } return true; } /* Finish fault handling; con->mutex must *not* be held here */ static void con_fault_finish(struct ceph_connection *con) { dout("%s %p\n", __func__, con); /* * in case we faulted due to authentication, invalidate our * current tickets so that we can get new ones. */ if (con->auth_retry) { dout("auth_retry %d, invalidating\n", con->auth_retry); if (con->ops->invalidate_authorizer) con->ops->invalidate_authorizer(con); con->auth_retry = 0; } if (con->ops->fault) con->ops->fault(con); } /* * Do some work on a connection. Drop a connection ref when we're done. */ static void ceph_con_workfn(struct work_struct *work) { struct ceph_connection *con = container_of(work, struct ceph_connection, work.work); bool fault; mutex_lock(&con->mutex); while (true) { int ret; if ((fault = con_sock_closed(con))) { dout("%s: con %p SOCK_CLOSED\n", __func__, con); break; } if (con_backoff(con)) { dout("%s: con %p BACKOFF\n", __func__, con); break; } if (con->state == CON_STATE_STANDBY) { dout("%s: con %p STANDBY\n", __func__, con); break; } if (con->state == CON_STATE_CLOSED) { dout("%s: con %p CLOSED\n", __func__, con); BUG_ON(con->sock); break; } if (con->state == CON_STATE_PREOPEN) { dout("%s: con %p PREOPEN\n", __func__, con); BUG_ON(con->sock); } ret = try_read(con); if (ret < 0) { if (ret == -EAGAIN) continue; if (!con->error_msg) con->error_msg = "socket error on read"; fault = true; break; } ret = try_write(con); if (ret < 0) { if (ret == -EAGAIN) continue; if (!con->error_msg) con->error_msg = "socket error on write"; fault = true; } break; /* If we make it to here, we're done */ } if (fault) con_fault(con); mutex_unlock(&con->mutex); if (fault) con_fault_finish(con); con->ops->put(con); } /* * Generic error/fault handler. A retry mechanism is used with * exponential backoff */ static void con_fault(struct ceph_connection *con) { dout("fault %p state %lu to peer %s\n", con, con->state, ceph_pr_addr(&con->peer_addr.in_addr)); pr_warn("%s%lld %s %s\n", ENTITY_NAME(con->peer_name), ceph_pr_addr(&con->peer_addr.in_addr), con->error_msg); con->error_msg = NULL; WARN_ON(con->state != CON_STATE_CONNECTING && con->state != CON_STATE_NEGOTIATING && con->state != CON_STATE_OPEN); con_close_socket(con); if (con_flag_test(con, CON_FLAG_LOSSYTX)) { dout("fault on LOSSYTX channel, marking CLOSED\n"); con->state = CON_STATE_CLOSED; return; } if (con->in_msg) { BUG_ON(con->in_msg->con != con); ceph_msg_put(con->in_msg); con->in_msg = NULL; } if (con->out_msg) { BUG_ON(con->out_msg->con != con); ceph_msg_put(con->out_msg); con->out_msg = NULL; } /* Requeue anything that hasn't been acked */ list_splice_init(&con->out_sent, &con->out_queue); /* If there are no messages queued or keepalive pending, place * the connection in a STANDBY state */ if (list_empty(&con->out_queue) && !con_flag_test(con, CON_FLAG_KEEPALIVE_PENDING)) { dout("fault %p setting STANDBY clearing WRITE_PENDING\n", con); con_flag_clear(con, CON_FLAG_WRITE_PENDING); con->state = CON_STATE_STANDBY; } else { /* retry after a delay. */ con->state = CON_STATE_PREOPEN; if (con->delay == 0) con->delay = BASE_DELAY_INTERVAL; else if (con->delay < MAX_DELAY_INTERVAL) con->delay *= 2; con_flag_set(con, CON_FLAG_BACKOFF); queue_con(con); } } /* * initialize a new messenger instance */ void ceph_messenger_init(struct ceph_messenger *msgr, struct ceph_entity_addr *myaddr) { spin_lock_init(&msgr->global_seq_lock); if (myaddr) msgr->inst.addr = *myaddr; /* select a random nonce */ msgr->inst.addr.type = 0; get_random_bytes(&msgr->inst.addr.nonce, sizeof(msgr->inst.addr.nonce)); encode_my_addr(msgr); atomic_set(&msgr->stopping, 0); write_pnet(&msgr->net, get_net(current->nsproxy->net_ns)); dout("%s %p\n", __func__, msgr); } EXPORT_SYMBOL(ceph_messenger_init); void ceph_messenger_fini(struct ceph_messenger *msgr) { put_net(read_pnet(&msgr->net)); } EXPORT_SYMBOL(ceph_messenger_fini); static void msg_con_set(struct ceph_msg *msg, struct ceph_connection *con) { if (msg->con) msg->con->ops->put(msg->con); msg->con = con ? con->ops->get(con) : NULL; BUG_ON(msg->con != con); } static void clear_standby(struct ceph_connection *con) { /* come back from STANDBY? */ if (con->state == CON_STATE_STANDBY) { dout("clear_standby %p and ++connect_seq\n", con); con->state = CON_STATE_PREOPEN; con->connect_seq++; WARN_ON(con_flag_test(con, CON_FLAG_WRITE_PENDING)); WARN_ON(con_flag_test(con, CON_FLAG_KEEPALIVE_PENDING)); } } /* * Queue up an outgoing message on the given connection. */ void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg) { /* set src+dst */ msg->hdr.src = con->msgr->inst.name; BUG_ON(msg->front.iov_len != le32_to_cpu(msg->hdr.front_len)); msg->needs_out_seq = true; mutex_lock(&con->mutex); if (con->state == CON_STATE_CLOSED) { dout("con_send %p closed, dropping %p\n", con, msg); ceph_msg_put(msg); mutex_unlock(&con->mutex); return; } msg_con_set(msg, con); BUG_ON(!list_empty(&msg->list_head)); list_add_tail(&msg->list_head, &con->out_queue); dout("----- %p to %s%lld %d=%s len %d+%d+%d -----\n", msg, ENTITY_NAME(con->peer_name), le16_to_cpu(msg->hdr.type), ceph_msg_type_name(le16_to_cpu(msg->hdr.type)), le32_to_cpu(msg->hdr.front_len), le32_to_cpu(msg->hdr.middle_len), le32_to_cpu(msg->hdr.data_len)); clear_standby(con); mutex_unlock(&con->mutex); /* if there wasn't anything waiting to send before, queue * new work */ if (con_flag_test_and_set(con, CON_FLAG_WRITE_PENDING) == 0) queue_con(con); } EXPORT_SYMBOL(ceph_con_send); /* * Revoke a message that was previously queued for send */ void ceph_msg_revoke(struct ceph_msg *msg) { struct ceph_connection *con = msg->con; if (!con) { dout("%s msg %p null con\n", __func__, msg); return; /* Message not in our possession */ } mutex_lock(&con->mutex); if (!list_empty(&msg->list_head)) { dout("%s %p msg %p - was on queue\n", __func__, con, msg); list_del_init(&msg->list_head); msg->hdr.seq = 0; ceph_msg_put(msg); } if (con->out_msg == msg) { BUG_ON(con->out_skip); /* footer */ if (con->out_msg_done) { con->out_skip += con_out_kvec_skip(con); } else { BUG_ON(!msg->data_length); con->out_skip += sizeof_footer(con); } /* data, middle, front */ if (msg->data_length) con->out_skip += msg->cursor.total_resid; if (msg->middle) con->out_skip += con_out_kvec_skip(con); con->out_skip += con_out_kvec_skip(con); dout("%s %p msg %p - was sending, will write %d skip %d\n", __func__, con, msg, con->out_kvec_bytes, con->out_skip); msg->hdr.seq = 0; con->out_msg = NULL; ceph_msg_put(msg); } mutex_unlock(&con->mutex); } /* * Revoke a message that we may be reading data into */ void ceph_msg_revoke_incoming(struct ceph_msg *msg) { struct ceph_connection *con = msg->con; if (!con) { dout("%s msg %p null con\n", __func__, msg); return; /* Message not in our possession */ } mutex_lock(&con->mutex); if (con->in_msg == msg) { unsigned int front_len = le32_to_cpu(con->in_hdr.front_len); unsigned int middle_len = le32_to_cpu(con->in_hdr.middle_len); unsigned int data_len = le32_to_cpu(con->in_hdr.data_len); /* skip rest of message */ dout("%s %p msg %p revoked\n", __func__, con, msg); con->in_base_pos = con->in_base_pos - sizeof(struct ceph_msg_header) - front_len - middle_len - data_len - sizeof(struct ceph_msg_footer); ceph_msg_put(con->in_msg); con->in_msg = NULL; con->in_tag = CEPH_MSGR_TAG_READY; con->in_seq++; } else { dout("%s %p in_msg %p msg %p no-op\n", __func__, con, con->in_msg, msg); } mutex_unlock(&con->mutex); } /* * Queue a keepalive byte to ensure the tcp connection is alive. */ void ceph_con_keepalive(struct ceph_connection *con) { dout("con_keepalive %p\n", con); mutex_lock(&con->mutex); clear_standby(con); con_flag_set(con, CON_FLAG_KEEPALIVE_PENDING); mutex_unlock(&con->mutex); if (con_flag_test_and_set(con, CON_FLAG_WRITE_PENDING) == 0) queue_con(con); } EXPORT_SYMBOL(ceph_con_keepalive); bool ceph_con_keepalive_expired(struct ceph_connection *con, unsigned long interval) { if (interval > 0 && (con->peer_features & CEPH_FEATURE_MSGR_KEEPALIVE2)) { struct timespec64 now; struct timespec64 ts; ktime_get_real_ts64(&now); jiffies_to_timespec64(interval, &ts); ts = timespec64_add(con->last_keepalive_ack, ts); return timespec64_compare(&now, &ts) >= 0; } return false; } static struct ceph_msg_data *ceph_msg_data_create(enum ceph_msg_data_type type) { struct ceph_msg_data *data; if (WARN_ON(!ceph_msg_data_type_valid(type))) return NULL; data = kmem_cache_zalloc(ceph_msg_data_cache, GFP_NOFS); if (!data) return NULL; data->type = type; INIT_LIST_HEAD(&data->links); return data; } static void ceph_msg_data_destroy(struct ceph_msg_data *data) { if (!data) return; WARN_ON(!list_empty(&data->links)); if (data->type == CEPH_MSG_DATA_PAGELIST) ceph_pagelist_release(data->pagelist); kmem_cache_free(ceph_msg_data_cache, data); } void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages, size_t length, size_t alignment) { struct ceph_msg_data *data; BUG_ON(!pages); BUG_ON(!length); data = ceph_msg_data_create(CEPH_MSG_DATA_PAGES); BUG_ON(!data); data->pages = pages; data->length = length; data->alignment = alignment & ~PAGE_MASK; list_add_tail(&data->links, &msg->data); msg->data_length += length; } EXPORT_SYMBOL(ceph_msg_data_add_pages); void ceph_msg_data_add_pagelist(struct ceph_msg *msg, struct ceph_pagelist *pagelist) { struct ceph_msg_data *data; BUG_ON(!pagelist); BUG_ON(!pagelist->length); data = ceph_msg_data_create(CEPH_MSG_DATA_PAGELIST); BUG_ON(!data); data->pagelist = pagelist; list_add_tail(&data->links, &msg->data); msg->data_length += pagelist->length; } EXPORT_SYMBOL(ceph_msg_data_add_pagelist); #ifdef CONFIG_BLOCK void ceph_msg_data_add_bio(struct ceph_msg *msg, struct ceph_bio_iter *bio_pos, u32 length) { struct ceph_msg_data *data; data = ceph_msg_data_create(CEPH_MSG_DATA_BIO); BUG_ON(!data); data->bio_pos = *bio_pos; data->bio_length = length; list_add_tail(&data->links, &msg->data); msg->data_length += length; } EXPORT_SYMBOL(ceph_msg_data_add_bio); #endif /* CONFIG_BLOCK */ void ceph_msg_data_add_bvecs(struct ceph_msg *msg, struct ceph_bvec_iter *bvec_pos) { struct ceph_msg_data *data; data = ceph_msg_data_create(CEPH_MSG_DATA_BVECS); BUG_ON(!data); data->bvec_pos = *bvec_pos; list_add_tail(&data->links, &msg->data); msg->data_length += bvec_pos->iter.bi_size; } EXPORT_SYMBOL(ceph_msg_data_add_bvecs); /* * construct a new message with given type, size * the new msg has a ref count of 1. */ struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags, bool can_fail) { struct ceph_msg *m; m = kmem_cache_zalloc(ceph_msg_cache, flags); if (m == NULL) goto out; m->hdr.type = cpu_to_le16(type); m->hdr.priority = cpu_to_le16(CEPH_MSG_PRIO_DEFAULT); m->hdr.front_len = cpu_to_le32(front_len); INIT_LIST_HEAD(&m->list_head); kref_init(&m->kref); INIT_LIST_HEAD(&m->data); /* front */ if (front_len) { m->front.iov_base = ceph_kvmalloc(front_len, flags); if (m->front.iov_base == NULL) { dout("ceph_msg_new can't allocate %d bytes\n", front_len); goto out2; } } else { m->front.iov_base = NULL; } m->front_alloc_len = m->front.iov_len = front_len; dout("ceph_msg_new %p front %d\n", m, front_len); return m; out2: ceph_msg_put(m); out: if (!can_fail) { pr_err("msg_new can't create type %d front %d\n", type, front_len); WARN_ON(1); } else { dout("msg_new can't create type %d front %d\n", type, front_len); } return NULL; } EXPORT_SYMBOL(ceph_msg_new); /* * Allocate "middle" portion of a message, if it is needed and wasn't * allocated by alloc_msg. This allows us to read a small fixed-size * per-type header in the front and then gracefully fail (i.e., * propagate the error to the caller based on info in the front) when * the middle is too large. */ static int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg) { int type = le16_to_cpu(msg->hdr.type); int middle_len = le32_to_cpu(msg->hdr.middle_len); dout("alloc_middle %p type %d %s middle_len %d\n", msg, type, ceph_msg_type_name(type), middle_len); BUG_ON(!middle_len); BUG_ON(msg->middle); msg->middle = ceph_buffer_new(middle_len, GFP_NOFS); if (!msg->middle) return -ENOMEM; return 0; } /* * Allocate a message for receiving an incoming message on a * connection, and save the result in con->in_msg. Uses the * connection's private alloc_msg op if available. * * Returns 0 on success, or a negative error code. * * On success, if we set *skip = 1: * - the next message should be skipped and ignored. * - con->in_msg == NULL * or if we set *skip = 0: * - con->in_msg is non-null. * On error (ENOMEM, EAGAIN, ...), * - con->in_msg == NULL */ static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip) { struct ceph_msg_header *hdr = &con->in_hdr; int middle_len = le32_to_cpu(hdr->middle_len); struct ceph_msg *msg; int ret = 0; BUG_ON(con->in_msg != NULL); BUG_ON(!con->ops->alloc_msg); mutex_unlock(&con->mutex); msg = con->ops->alloc_msg(con, hdr, skip); mutex_lock(&con->mutex); if (con->state != CON_STATE_OPEN) { if (msg) ceph_msg_put(msg); return -EAGAIN; } if (msg) { BUG_ON(*skip); msg_con_set(msg, con); con->in_msg = msg; } else { /* * Null message pointer means either we should skip * this message or we couldn't allocate memory. The * former is not an error. */ if (*skip) return 0; con->error_msg = "error allocating memory for incoming message"; return -ENOMEM; } memcpy(&con->in_msg->hdr, &con->in_hdr, sizeof(con->in_hdr)); if (middle_len && !con->in_msg->middle) { ret = ceph_alloc_middle(con, con->in_msg); if (ret < 0) { ceph_msg_put(con->in_msg); con->in_msg = NULL; } } return ret; } /* * Free a generically kmalloc'd message. */ static void ceph_msg_free(struct ceph_msg *m) { dout("%s %p\n", __func__, m); kvfree(m->front.iov_base); kmem_cache_free(ceph_msg_cache, m); } static void ceph_msg_release(struct kref *kref) { struct ceph_msg *m = container_of(kref, struct ceph_msg, kref); struct ceph_msg_data *data, *next; dout("%s %p\n", __func__, m); WARN_ON(!list_empty(&m->list_head)); msg_con_set(m, NULL); /* drop middle, data, if any */ if (m->middle) { ceph_buffer_put(m->middle); m->middle = NULL; } list_for_each_entry_safe(data, next, &m->data, links) { list_del_init(&data->links); ceph_msg_data_destroy(data); } m->data_length = 0; if (m->pool) ceph_msgpool_put(m->pool, m); else ceph_msg_free(m); } struct ceph_msg *ceph_msg_get(struct ceph_msg *msg) { dout("%s %p (was %d)\n", __func__, msg, kref_read(&msg->kref)); kref_get(&msg->kref); return msg; } EXPORT_SYMBOL(ceph_msg_get); void ceph_msg_put(struct ceph_msg *msg) { dout("%s %p (was %d)\n", __func__, msg, kref_read(&msg->kref)); kref_put(&msg->kref, ceph_msg_release); } EXPORT_SYMBOL(ceph_msg_put); void ceph_msg_dump(struct ceph_msg *msg) { pr_debug("msg_dump %p (front_alloc_len %d length %zd)\n", msg, msg->front_alloc_len, msg->data_length); print_hex_dump(KERN_DEBUG, "header: ", DUMP_PREFIX_OFFSET, 16, 1, &msg->hdr, sizeof(msg->hdr), true); print_hex_dump(KERN_DEBUG, " front: ", DUMP_PREFIX_OFFSET, 16, 1, msg->front.iov_base, msg->front.iov_len, true); if (msg->middle) print_hex_dump(KERN_DEBUG, "middle: ", DUMP_PREFIX_OFFSET, 16, 1, msg->middle->vec.iov_base, msg->middle->vec.iov_len, true); print_hex_dump(KERN_DEBUG, "footer: ", DUMP_PREFIX_OFFSET, 16, 1, &msg->footer, sizeof(msg->footer), true); } EXPORT_SYMBOL(ceph_msg_dump);