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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/ceph/messenger.c
Initial import
Diffstat (limited to 'net/ceph/messenger.c')
-rw-r--r--net/ceph/messenger.c3395
1 files changed, 3395 insertions, 0 deletions
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
new file mode 100644
index 000000000..967080a9f
--- /dev/null
+++ b/net/ceph/messenger.c
@@ -0,0 +1,3395 @@
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/crc32c.h>
+#include <linux/ctype.h>
+#include <linux/highmem.h>
+#include <linux/inet.h>
+#include <linux/kthread.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <linux/socket.h>
+#include <linux/string.h>
+#ifdef CONFIG_BLOCK
+#include <linux/bio.h>
+#endif /* CONFIG_BLOCK */
+#include <linux/dns_resolver.h>
+#include <net/tcp.h>
+
+#include <linux/ceph/ceph_features.h>
+#include <linux/ceph/libceph.h>
+#include <linux/ceph/messenger.h>
+#include <linux/ceph/decode.h>
+#include <linux/ceph/pagelist.h>
+#include <linux/export.h>
+
+#define list_entry_next(pos, member) \
+ list_entry(pos->member.next, typeof(*pos), member)
+
+/*
+ * 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;
+
+#ifdef CONFIG_LOCKDEP
+static struct lock_class_key socket_class;
+#endif
+
+/*
+ * When skipping (ignoring) a block of input we read it into a "skip
+ * buffer," which is this many bytes in size.
+ */
+#define SKIP_BUF_SIZE 1024
+
+static void queue_con(struct ceph_connection *con);
+static void cancel_con(struct ceph_connection *con);
+static void con_work(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_create("ceph_msg",
+ sizeof (struct ceph_msg),
+ __alignof__(struct ceph_msg), 0, NULL);
+
+ if (!ceph_msg_cache)
+ return -ENOMEM;
+
+ BUG_ON(ceph_msg_data_cache);
+ ceph_msg_data_cache = kmem_cache_create("ceph_msg_data",
+ sizeof (struct ceph_msg_data),
+ __alignof__(struct ceph_msg_data),
+ 0, NULL);
+ 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;
+ }
+
+ ceph_msgr_slab_exit();
+
+ BUG_ON(zero_page == NULL);
+ kunmap(zero_page);
+ page_cache_release(zero_page);
+ zero_page = NULL;
+}
+
+int ceph_msgr_init(void)
+{
+ BUG_ON(zero_page != NULL);
+ zero_page = ZERO_PAGE(0);
+ page_cache_get(zero_page);
+
+ if (ceph_msgr_slab_init())
+ return -ENOMEM;
+
+ /*
+ * 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;
+}
+EXPORT_SYMBOL(ceph_msgr_init);
+
+void ceph_msgr_exit(void)
+{
+ BUG_ON(ceph_msgr_wq == NULL);
+
+ _ceph_msgr_exit();
+}
+EXPORT_SYMBOL(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__);
+ 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;
+ int ret;
+
+ BUG_ON(con->sock);
+ ret = sock_create_kern(con->peer_addr.in_addr.ss_family, SOCK_STREAM,
+ IPPROTO_TCP, &sock);
+ 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 (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;
+}
+
+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;
+
+ r = kernel_recvmsg(sock, &msg, &iov, 1, len, 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)
+{
+ void *kaddr;
+ int ret;
+
+ BUG_ON(page_offset + length > PAGE_SIZE);
+
+ kaddr = kmap(page);
+ BUG_ON(!kaddr);
+ ret = ceph_tcp_recvmsg(sock, kaddr + page_offset, length);
+ kunmap(page);
+
+ return ret;
+}
+
+/*
+ * 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)
+{
+ int ret;
+ struct kvec iov;
+
+ /* sendpage cannot properly handle pages with page_count == 0,
+ * we need to fallback to sendmsg if that's the case */
+ if (page_count(page) >= 1)
+ return __ceph_tcp_sendpage(sock, page, offset, size, more);
+
+ iov.iov_base = kmap(page) + offset;
+ iov.iov_len = size;
+ ret = ceph_tcp_sendmsg(sock, &iov, 1, size, more);
+ kunmap(page);
+
+ 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);
+ BUG_ON(msg->con == NULL);
+ msg->con->ops->put(msg->con);
+ msg->con = NULL;
+
+ 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);
+ con->in_msg->con = NULL;
+ ceph_msg_put(con->in_msg);
+ con->in_msg = NULL;
+ con->ops->put(con);
+ }
+
+ con->connect_seq = 0;
+ con->out_seq = 0;
+ if (con->out_msg) {
+ ceph_msg_put(con->out_msg);
+ con->out_msg = NULL;
+ }
+ con->in_seq = 0;
+ con->in_seq_acked = 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, con_work);
+
+ 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)
+{
+ 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;
+
+ index = con->out_kvec_left;
+ 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;
+}
+
+#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 bio *bio;
+
+ BUG_ON(data->type != CEPH_MSG_DATA_BIO);
+
+ bio = data->bio;
+ BUG_ON(!bio);
+
+ cursor->resid = min(length, data->bio_length);
+ cursor->bio = bio;
+ cursor->bvec_iter = bio->bi_iter;
+ cursor->last_piece =
+ cursor->resid <= bio_iter_len(bio, cursor->bvec_iter);
+}
+
+static struct page *ceph_msg_data_bio_next(struct ceph_msg_data_cursor *cursor,
+ size_t *page_offset,
+ size_t *length)
+{
+ struct ceph_msg_data *data = cursor->data;
+ struct bio *bio;
+ struct bio_vec bio_vec;
+
+ BUG_ON(data->type != CEPH_MSG_DATA_BIO);
+
+ bio = cursor->bio;
+ BUG_ON(!bio);
+
+ bio_vec = bio_iter_iovec(bio, cursor->bvec_iter);
+
+ *page_offset = (size_t) bio_vec.bv_offset;
+ BUG_ON(*page_offset >= PAGE_SIZE);
+ if (cursor->last_piece) /* pagelist offset is always 0 */
+ *length = cursor->resid;
+ else
+ *length = (size_t) bio_vec.bv_len;
+ BUG_ON(*length > cursor->resid);
+ BUG_ON(*page_offset + *length > PAGE_SIZE);
+
+ return bio_vec.bv_page;
+}
+
+static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor,
+ size_t bytes)
+{
+ struct bio *bio;
+ struct bio_vec bio_vec;
+
+ BUG_ON(cursor->data->type != CEPH_MSG_DATA_BIO);
+
+ bio = cursor->bio;
+ BUG_ON(!bio);
+
+ bio_vec = bio_iter_iovec(bio, cursor->bvec_iter);
+
+ /* Advance the cursor offset */
+
+ BUG_ON(cursor->resid < bytes);
+ cursor->resid -= bytes;
+
+ bio_advance_iter(bio, &cursor->bvec_iter, bytes);
+
+ if (bytes < bio_vec.bv_len)
+ return false; /* more bytes to process in this segment */
+
+ /* Move on to the next segment, and possibly the next bio */
+
+ if (!cursor->bvec_iter.bi_size) {
+ bio = bio->bi_next;
+ cursor->bio = bio;
+ if (bio)
+ cursor->bvec_iter = bio->bi_iter;
+ else
+ memset(&cursor->bvec_iter, 0,
+ sizeof(cursor->bvec_iter));
+ }
+
+ if (!cursor->last_piece) {
+ BUG_ON(!cursor->resid);
+ BUG_ON(!bio);
+ /* A short read is OK, so use <= rather than == */
+ if (cursor->resid <= bio_iter_len(bio, cursor->bvec_iter))
+ cursor->last_piece = true;
+ }
+
+ return true;
+}
+#endif /* CONFIG_BLOCK */
+
+/*
+ * 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_entry_next(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_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_NONE:
+ default:
+ page = NULL;
+ break;
+ }
+ BUG_ON(!page);
+ BUG_ON(*page_offset + *length > PAGE_SIZE);
+ BUG_ON(!*length);
+ 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 bool 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_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_entry_next(cursor->data, links);
+ __ceph_msg_data_cursor_init(cursor);
+ new_piece = true;
+ }
+ cursor->need_crc = new_piece;
+
+ return new_piece;
+}
+
+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;
+ int v = con->out_kvec_left;
+
+ m->footer.flags |= CEPH_MSG_FOOTER_COMPLETE;
+
+ dout("prepare_write_message_footer %p\n", con);
+ con->out_kvec_is_msg = true;
+ con->out_kvec[v].iov_base = &m->footer;
+ if (con->peer_features & CEPH_FEATURE_MSG_AUTH) {
+ if (con->ops->sign_message)
+ con->ops->sign_message(con, m);
+ else
+ m->footer.sig = 0;
+ con->out_kvec[v].iov_len = sizeof(m->footer);
+ con->out_kvec_bytes += sizeof(m->footer);
+ } else {
+ m->old_footer.flags = m->footer.flags;
+ con->out_kvec[v].iov_len = sizeof(m->old_footer);
+ con->out_kvec_bytes += sizeof(m->old_footer);
+ }
+ con->out_kvec_left++;
+ 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_kvec_is_msg = true;
+ 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;
+ }
+ WARN_ON(m->data_length != le32_to_cpu(m->hdr.data_len));
+
+ 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);
+ BUG_ON(le32_to_cpu(m->hdr.front_len) != m->front.iov_len);
+
+ /* tag + hdr + front + middle */
+ con_out_kvec_add(con, sizeof (tag_msg), &tag_msg);
+ con_out_kvec_add(con, sizeof (m->hdr), &m->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 crc (except data pages), footer */
+ crc = crc32c(0, &m->hdr, offsetof(struct ceph_msg_header, crc));
+ con->out_msg->hdr.crc = cpu_to_le32(crc);
+ con->out_msg->footer.flags = 0;
+
+ 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));
+
+ /* 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);
+ con_out_kvec_add(con, sizeof (tag_keepalive), &tag_keepalive);
+ con_flag_set(con, CON_FLAG_WRITE_PENDING);
+}
+
+/*
+ * Connection negotiation.
+ */
+
+static struct ceph_auth_handshake *get_connect_authorizer(struct ceph_connection *con,
+ int *auth_proto)
+{
+ struct ceph_auth_handshake *auth;
+
+ if (!con->ops->get_authorizer) {
+ con->out_connect.authorizer_protocol = CEPH_AUTH_UNKNOWN;
+ con->out_connect.authorizer_len = 0;
+ return NULL;
+ }
+
+ /* Can't hold the mutex while getting authorizer */
+ mutex_unlock(&con->mutex);
+ auth = con->ops->get_authorizer(con, auth_proto, con->auth_retry);
+ mutex_lock(&con->mutex);
+
+ if (IS_ERR(auth))
+ return auth;
+ if (con->state != CON_STATE_NEGOTIATING)
+ return ERR_PTR(-EAGAIN);
+
+ con->auth_reply_buf = auth->authorizer_reply_buf;
+ con->auth_reply_buf_len = auth->authorizer_reply_buf_len;
+ return auth;
+}
+
+/*
+ * 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 int prepare_write_connect(struct ceph_connection *con)
+{
+ unsigned int global_seq = get_global_seq(con->msgr, 0);
+ int proto;
+ int auth_proto;
+ struct ceph_auth_handshake *auth;
+
+ 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(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;
+
+ auth_proto = CEPH_AUTH_UNKNOWN;
+ auth = get_connect_authorizer(con, &auth_proto);
+ if (IS_ERR(auth))
+ return PTR_ERR(auth);
+
+ con->out_connect.authorizer_protocol = cpu_to_le32(auth_proto);
+ con->out_connect.authorizer_len = auth ?
+ cpu_to_le32(auth->authorizer_buf_len) : 0;
+
+ con_out_kvec_add(con, sizeof (con->out_connect),
+ &con->out_connect);
+ if (auth && auth->authorizer_buf_len)
+ con_out_kvec_add(con, auth->authorizer_buf_len,
+ auth->authorizer_buf);
+
+ con->out_more = 0;
+ con_flag_set(con, CON_FLAG_WRITE_PENDING);
+
+ 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;
+ con->out_kvec_is_msg = false;
+ 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 = !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->resid) {
+ struct page *page;
+ size_t page_offset;
+ size_t length;
+ bool last_piece;
+ bool need_crc;
+ int ret;
+
+ page = ceph_msg_data_next(&msg->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);
+ need_crc = ceph_msg_data_advance(&msg->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;
+
+ while (con->out_skip > 0) {
+ size_t size = min(con->out_skip, (int) PAGE_CACHE_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;
+}
+
+/*
+ * 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;
+
+ size = le32_to_cpu(con->in_reply.authorizer_len);
+ end += size;
+ ret = read_partial(con, end, size, con->auth_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)
+{
+ switch (ss->ss_family) {
+ case AF_INET:
+ return ((struct sockaddr_in *)ss)->sin_addr.s_addr == 0;
+ case AF_INET6:
+ return
+ ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[0] == 0 &&
+ ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[1] == 0 &&
+ ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[2] == 0 &&
+ ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[3] == 0;
+ }
+ return false;
+}
+
+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 = con->msgr->supported_features;
+ u64 req_feat = con->msgr->required_features;
+ u64 server_feat = ceph_sanitize_features(
+ le64_to_cpu(con->in_reply.features));
+ int ret;
+
+ dout("process_connect on %p tag %d\n", con, (int)con->in_tag);
+
+ 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;
+
+ while (!list_empty(&con->out_sent)) {
+ m = list_first_entry(&con->out_sent, struct ceph_msg,
+ list_head);
+ 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;
+ const bool do_datacrc = !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->resid) {
+ page = ceph_msg_data_next(&msg->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);
+ (void) ceph_msg_data_advance(&msg->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 = !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(m->footer);
+ con->in_tag = CEPH_MSGR_TAG_READY;
+ return 0;
+ } 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 (con->in_msg && data_len > con->in_msg->data_length) {
+ pr_warn("%s skipping long message (%u > %zd)\n",
+ __func__, data_len, con->in_msg->data_length);
+ ceph_msg_put(con->in_msg);
+ con->in_msg = NULL;
+ skip = 1;
+ }
+ if (skip) {
+ /* skip this message */
+ dout("alloc_msg said skip message\n");
+ con->in_base_pos = -front_len - middle_len - data_len -
+ sizeof(m->footer);
+ con->in_tag = CEPH_MSGR_TAG_READY;
+ con->in_seq++;
+ return 0;
+ }
+
+ 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 */
+ if (need_sign)
+ size = sizeof(m->footer);
+ else
+ size = sizeof(m->old_footer);
+
+ 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(con, 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;
+
+ BUG_ON(con->in_msg->con != con);
+ con->in_msg->con = NULL;
+ msg = con->in_msg;
+ con->in_msg = NULL;
+ con->ops->put(con);
+
+ /* 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);
+}
+
+
+/*
+ * 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);
+
+more:
+ dout("try_write out_kvec_bytes %d\n", con->out_kvec_bytes);
+
+ /* 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_kvec:
+ /* kvec data queued? */
+ if (con->out_skip) {
+ ret = write_partial_skip(con);
+ if (ret <= 0)
+ goto out;
+ }
+ if (con->out_kvec_left) {
+ ret = write_partial_kvec(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_kvec; /* 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) {
+ /* 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;
+ }
+ if (con_flag_test_and_clear(con, CON_FLAG_KEEPALIVE_PENDING)) {
+ prepare_write_keepalive(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.
+ *
+ * FIXME: there must be a better way to do this!
+ */
+ static char buf[SKIP_BUF_SIZE];
+ int skip = min((int) sizeof (buf), -con->in_base_pos);
+
+ dout("skipping %d / %d bytes\n", skip, -con->in_base_pos);
+ ret = ceph_tcp_recvmsg(con->sock, buf, skip);
+ if (ret <= 0)
+ goto out;
+ 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_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";
+ /* 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;
+ }
+
+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)
+{
+ /*
+ * in case we faulted due to authentication, invalidate our
+ * current tickets so that we can get new ones.
+ */
+ if (con->auth_retry && con->ops->invalidate_authorizer) {
+ dout("calling invalidate_authorizer()\n");
+ con->ops->invalidate_authorizer(con);
+ }
+
+ if (con->ops->fault)
+ con->ops->fault(con);
+}
+
+/*
+ * Do some work on a connection. Drop a connection ref when we're done.
+ */
+static void con_work(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);
+ con->in_msg->con = NULL;
+ ceph_msg_put(con->in_msg);
+ con->in_msg = NULL;
+ con->ops->put(con);
+ }
+
+ /* 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,
+ u64 supported_features,
+ u64 required_features,
+ bool nocrc,
+ bool tcp_nodelay)
+{
+ msgr->supported_features = supported_features;
+ msgr->required_features = required_features;
+
+ 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);
+ msgr->nocrc = nocrc;
+ msgr->tcp_nodelay = tcp_nodelay;
+
+ atomic_set(&msgr->stopping, 0);
+
+ dout("%s %p\n", __func__, msgr);
+}
+EXPORT_SYMBOL(ceph_messenger_init);
+
+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;
+ }
+
+ BUG_ON(msg->con != NULL);
+ msg->con = con->ops->get(con);
+ BUG_ON(msg->con == NULL);
+
+ 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)
+ 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);
+ BUG_ON(msg->con == NULL);
+ msg->con->ops->put(msg->con);
+ msg->con = NULL;
+ msg->hdr.seq = 0;
+
+ ceph_msg_put(msg);
+ }
+ if (con->out_msg == msg) {
+ dout("%s %p msg %p - was sending\n", __func__, con, msg);
+ con->out_msg = NULL;
+ if (con->out_kvec_is_msg) {
+ con->out_skip = con->out_kvec_bytes;
+ con->out_kvec_is_msg = false;
+ }
+ msg->hdr.seq = 0;
+
+ 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;
+
+ BUG_ON(msg == NULL);
+ if (!msg->con) {
+ dout("%s msg %p null con\n", __func__, msg);
+
+ return; /* Message not in our possession */
+ }
+
+ con = msg->con;
+ 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);
+ mutex_unlock(&con->mutex);
+ if (con_flag_test_and_set(con, CON_FLAG_KEEPALIVE_PENDING) == 0 &&
+ con_flag_test_and_set(con, CON_FLAG_WRITE_PENDING) == 0)
+ queue_con(con);
+}
+EXPORT_SYMBOL(ceph_con_keepalive);
+
+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)
+ 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 bio *bio,
+ size_t length)
+{
+ struct ceph_msg_data *data;
+
+ BUG_ON(!bio);
+
+ data = ceph_msg_data_create(CEPH_MSG_DATA_BIO);
+ BUG_ON(!data);
+ data->bio = bio;
+ 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 */
+
+/*
+ * 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);
+ con->in_msg = msg;
+ con->in_msg->con = con->ops->get(con);
+ BUG_ON(con->in_msg->con == NULL);
+ } 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);
+ LIST_HEAD(data);
+ struct list_head *links;
+ struct list_head *next;
+
+ dout("%s %p\n", __func__, m);
+ WARN_ON(!list_empty(&m->list_head));
+
+ /* drop middle, data, if any */
+ if (m->middle) {
+ ceph_buffer_put(m->middle);
+ m->middle = NULL;
+ }
+
+ list_splice_init(&m->data, &data);
+ list_for_each_safe(links, next, &data) {
+ struct ceph_msg_data *data;
+
+ data = list_entry(links, struct ceph_msg_data, links);
+ list_del_init(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,
+ atomic_read(&msg->kref.refcount));
+ 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,
+ atomic_read(&msg->kref.refcount));
+ 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);