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-rw-r--r--fs/ceph/messenger.c2271
1 files changed, 2271 insertions, 0 deletions
diff --git a/fs/ceph/messenger.c b/fs/ceph/messenger.c
new file mode 100644
index 00000000000..509f57d9ccb
--- /dev/null
+++ b/fs/ceph/messenger.c
@@ -0,0 +1,2271 @@
+#include "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>
+#include <net/tcp.h>
+
+#include "super.h"
+#include "messenger.h"
+#include "decode.h"
+#include "pagelist.h"
+
+/*
+ * 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.
+ */
+
+/* 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
+
+
+static void queue_con(struct ceph_connection *con);
+static void con_work(struct work_struct *);
+static void ceph_fault(struct ceph_connection *con);
+
+const char *ceph_name_type_str(int t)
+{
+ switch (t) {
+ case CEPH_ENTITY_TYPE_MON: return "mon";
+ case CEPH_ENTITY_TYPE_MDS: return "mds";
+ case CEPH_ENTITY_TYPE_OSD: return "osd";
+ case CEPH_ENTITY_TYPE_CLIENT: return "client";
+ case CEPH_ENTITY_TYPE_ADMIN: return "admin";
+ default: return "???";
+ }
+}
+
+/*
+ * nicely render a sockaddr as a string.
+ */
+#define MAX_ADDR_STR 20
+static char addr_str[MAX_ADDR_STR][40];
+static DEFINE_SPINLOCK(addr_str_lock);
+static int last_addr_str;
+
+const char *pr_addr(const struct sockaddr_storage *ss)
+{
+ int i;
+ char *s;
+ struct sockaddr_in *in4 = (void *)ss;
+ unsigned char *quad = (void *)&in4->sin_addr.s_addr;
+ struct sockaddr_in6 *in6 = (void *)ss;
+
+ spin_lock(&addr_str_lock);
+ i = last_addr_str++;
+ if (last_addr_str == MAX_ADDR_STR)
+ last_addr_str = 0;
+ spin_unlock(&addr_str_lock);
+ s = addr_str[i];
+
+ switch (ss->ss_family) {
+ case AF_INET:
+ sprintf(s, "%u.%u.%u.%u:%u",
+ (unsigned int)quad[0],
+ (unsigned int)quad[1],
+ (unsigned int)quad[2],
+ (unsigned int)quad[3],
+ (unsigned int)ntohs(in4->sin_port));
+ break;
+
+ case AF_INET6:
+ sprintf(s, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x:%u",
+ in6->sin6_addr.s6_addr16[0],
+ in6->sin6_addr.s6_addr16[1],
+ in6->sin6_addr.s6_addr16[2],
+ in6->sin6_addr.s6_addr16[3],
+ in6->sin6_addr.s6_addr16[4],
+ in6->sin6_addr.s6_addr16[5],
+ in6->sin6_addr.s6_addr16[6],
+ in6->sin6_addr.s6_addr16[7],
+ (unsigned int)ntohs(in6->sin6_port));
+ break;
+
+ default:
+ sprintf(s, "(unknown sockaddr family %d)", (int)ss->ss_family);
+ }
+
+ return s;
+}
+
+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.
+ */
+struct workqueue_struct *ceph_msgr_wq;
+
+int __init ceph_msgr_init(void)
+{
+ ceph_msgr_wq = create_workqueue("ceph-msgr");
+ if (IS_ERR(ceph_msgr_wq)) {
+ int ret = PTR_ERR(ceph_msgr_wq);
+ pr_err("msgr_init failed to create workqueue: %d\n", ret);
+ ceph_msgr_wq = NULL;
+ return ret;
+ }
+ return 0;
+}
+
+void ceph_msgr_exit(void)
+{
+ destroy_workqueue(ceph_msgr_wq);
+}
+
+/*
+ * socket callback functions
+ */
+
+/* data available on socket, or listen socket received a connect */
+static void ceph_data_ready(struct sock *sk, int count_unused)
+{
+ struct ceph_connection *con =
+ (struct ceph_connection *)sk->sk_user_data;
+ if (sk->sk_state != TCP_CLOSE_WAIT) {
+ dout("ceph_data_ready on %p state = %lu, queueing work\n",
+ con, con->state);
+ queue_con(con);
+ }
+}
+
+/* socket has buffer space for writing */
+static void ceph_write_space(struct sock *sk)
+{
+ struct ceph_connection *con =
+ (struct ceph_connection *)sk->sk_user_data;
+
+ /* only queue to workqueue if there is data we want to write. */
+ if (test_bit(WRITE_PENDING, &con->state)) {
+ dout("ceph_write_space %p queueing write work\n", con);
+ queue_con(con);
+ } else {
+ dout("ceph_write_space %p nothing to write\n", con);
+ }
+
+ /* since we have our own write_space, clear the SOCK_NOSPACE flag */
+ clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
+}
+
+/* socket's state has changed */
+static void ceph_state_change(struct sock *sk)
+{
+ struct ceph_connection *con =
+ (struct ceph_connection *)sk->sk_user_data;
+
+ dout("ceph_state_change %p state = %lu sk_state = %u\n",
+ con, con->state, sk->sk_state);
+
+ if (test_bit(CLOSED, &con->state))
+ return;
+
+ switch (sk->sk_state) {
+ case TCP_CLOSE:
+ dout("ceph_state_change TCP_CLOSE\n");
+ case TCP_CLOSE_WAIT:
+ dout("ceph_state_change TCP_CLOSE_WAIT\n");
+ if (test_and_set_bit(SOCK_CLOSED, &con->state) == 0) {
+ if (test_bit(CONNECTING, &con->state))
+ con->error_msg = "connection failed";
+ else
+ con->error_msg = "socket closed";
+ queue_con(con);
+ }
+ break;
+ case TCP_ESTABLISHED:
+ dout("ceph_state_change TCP_ESTABLISHED\n");
+ queue_con(con);
+ 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 = (void *)con;
+ sk->sk_data_ready = ceph_data_ready;
+ sk->sk_write_space = ceph_write_space;
+ sk->sk_state_change = ceph_state_change;
+}
+
+
+/*
+ * socket helpers
+ */
+
+/*
+ * initiate connection to a remote socket.
+ */
+static struct socket *ceph_tcp_connect(struct ceph_connection *con)
+{
+ struct sockaddr *paddr = (struct sockaddr *)&con->peer_addr.in_addr;
+ struct socket *sock;
+ int ret;
+
+ BUG_ON(con->sock);
+ ret = sock_create_kern(AF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
+ if (ret)
+ return ERR_PTR(ret);
+ con->sock = sock;
+ 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", pr_addr(&con->peer_addr.in_addr));
+
+ ret = sock->ops->connect(sock, paddr, sizeof(*paddr), O_NONBLOCK);
+ if (ret == -EINPROGRESS) {
+ dout("connect %s EINPROGRESS sk_state = %u\n",
+ pr_addr(&con->peer_addr.in_addr),
+ sock->sk->sk_state);
+ ret = 0;
+ }
+ if (ret < 0) {
+ pr_err("connect %s error %d\n",
+ pr_addr(&con->peer_addr.in_addr), ret);
+ sock_release(sock);
+ con->sock = NULL;
+ con->error_msg = "connect error";
+ }
+
+ if (ret < 0)
+ return ERR_PTR(ret);
+ return sock;
+}
+
+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 };
+
+ return kernel_recvmsg(sock, &msg, &iov, 1, len, msg.msg_flags);
+}
+
+/*
+ * 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 };
+
+ if (more)
+ msg.msg_flags |= MSG_MORE;
+ else
+ msg.msg_flags |= MSG_EOR; /* superfluous, but what the hell */
+
+ return kernel_sendmsg(sock, &msg, iov, kvlen, len);
+}
+
+
+/*
+ * Shutdown/close the socket for the given connection.
+ */
+static int con_close_socket(struct ceph_connection *con)
+{
+ int rc;
+
+ dout("con_close_socket on %p sock %p\n", con, con->sock);
+ if (!con->sock)
+ return 0;
+ set_bit(SOCK_CLOSED, &con->state);
+ rc = con->sock->ops->shutdown(con->sock, SHUT_RDWR);
+ sock_release(con->sock);
+ con->sock = NULL;
+ clear_bit(SOCK_CLOSED, &con->state);
+ 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 */
+ ceph_msg_remove_list(&con->out_queue);
+ ceph_msg_remove_list(&con->out_sent);
+
+ if (con->in_msg) {
+ ceph_msg_put(con->in_msg);
+ con->in_msg = NULL;
+ }
+
+ 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)
+{
+ dout("con_close %p peer %s\n", con, pr_addr(&con->peer_addr.in_addr));
+ set_bit(CLOSED, &con->state); /* in case there's queued work */
+ clear_bit(STANDBY, &con->state); /* avoid connect_seq bump */
+ clear_bit(LOSSYTX, &con->state); /* so we retry next connect */
+ clear_bit(KEEPALIVE_PENDING, &con->state);
+ clear_bit(WRITE_PENDING, &con->state);
+ mutex_lock(&con->mutex);
+ reset_connection(con);
+ cancel_delayed_work(&con->work);
+ mutex_unlock(&con->mutex);
+ queue_con(con);
+}
+
+/*
+ * Reopen a closed connection, with a new peer address.
+ */
+void ceph_con_open(struct ceph_connection *con, struct ceph_entity_addr *addr)
+{
+ dout("con_open %p %s\n", con, pr_addr(&addr->in_addr));
+ set_bit(OPENING, &con->state);
+ clear_bit(CLOSED, &con->state);
+ memcpy(&con->peer_addr, addr, sizeof(*addr));
+ con->delay = 0; /* reset backoff memory */
+ queue_con(con);
+}
+
+/*
+ * return true if this connection ever successfully opened
+ */
+bool ceph_con_opened(struct ceph_connection *con)
+{
+ return con->connect_seq > 0;
+}
+
+/*
+ * generic get/put
+ */
+struct ceph_connection *ceph_con_get(struct ceph_connection *con)
+{
+ dout("con_get %p nref = %d -> %d\n", con,
+ atomic_read(&con->nref), atomic_read(&con->nref) + 1);
+ if (atomic_inc_not_zero(&con->nref))
+ return con;
+ return NULL;
+}
+
+void ceph_con_put(struct ceph_connection *con)
+{
+ dout("con_put %p nref = %d -> %d\n", con,
+ atomic_read(&con->nref), atomic_read(&con->nref) - 1);
+ BUG_ON(atomic_read(&con->nref) == 0);
+ if (atomic_dec_and_test(&con->nref)) {
+ BUG_ON(con->sock);
+ kfree(con);
+ }
+}
+
+/*
+ * initialize a new connection.
+ */
+void ceph_con_init(struct ceph_messenger *msgr, struct ceph_connection *con)
+{
+ dout("con_init %p\n", con);
+ memset(con, 0, sizeof(*con));
+ atomic_set(&con->nref, 1);
+ con->msgr = msgr;
+ mutex_init(&con->mutex);
+ INIT_LIST_HEAD(&con->out_queue);
+ INIT_LIST_HEAD(&con->out_sent);
+ INIT_DELAYED_WORK(&con->work, con_work);
+}
+
+
+/*
+ * 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;
+}
+
+
+/*
+ * 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, int v)
+{
+ struct ceph_msg *m = con->out_msg;
+
+ dout("prepare_write_message_footer %p\n", con);
+ con->out_kvec_is_msg = true;
+ con->out_kvec[v].iov_base = &m->footer;
+ con->out_kvec[v].iov_len = sizeof(m->footer);
+ con->out_kvec_bytes += sizeof(m->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;
+ int v = 0;
+
+ con->out_kvec_bytes = 0;
+ 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[v].iov_base = &tag_ack;
+ con->out_kvec[v++].iov_len = 1;
+ con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
+ con->out_kvec[v].iov_base = &con->out_temp_ack;
+ con->out_kvec[v++].iov_len = sizeof(con->out_temp_ack);
+ con->out_kvec_bytes = 1 + sizeof(con->out_temp_ack);
+ }
+
+ m = list_first_entry(&con->out_queue,
+ struct ceph_msg, list_head);
+ con->out_msg = m;
+ if (test_bit(LOSSYTX, &con->state)) {
+ list_del_init(&m->list_head);
+ } else {
+ /* put message on sent list */
+ ceph_msg_get(m);
+ list_move_tail(&m->list_head, &con->out_sent);
+ }
+
+ m->hdr.seq = cpu_to_le64(++con->out_seq);
+
+ dout("prepare_write_message %p seq %lld type %d len %d+%d+%d %d pgs\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),
+ le32_to_cpu(m->hdr.data_len),
+ m->nr_pages);
+ BUG_ON(le32_to_cpu(m->hdr.front_len) != m->front.iov_len);
+
+ /* tag + hdr + front + middle */
+ con->out_kvec[v].iov_base = &tag_msg;
+ con->out_kvec[v++].iov_len = 1;
+ con->out_kvec[v].iov_base = &m->hdr;
+ con->out_kvec[v++].iov_len = sizeof(m->hdr);
+ con->out_kvec[v++] = m->front;
+ if (m->middle)
+ con->out_kvec[v++] = m->middle->vec;
+ con->out_kvec_left = v;
+ con->out_kvec_bytes += 1 + sizeof(m->hdr) + m->front.iov_len +
+ (m->middle ? m->middle->vec.iov_len : 0);
+ con->out_kvec_cur = con->out_kvec;
+
+ /* fill in crc (except data pages), footer */
+ con->out_msg->hdr.crc =
+ cpu_to_le32(crc32c(0, (void *)&m->hdr,
+ sizeof(m->hdr) - sizeof(m->hdr.crc)));
+ con->out_msg->footer.flags = CEPH_MSG_FOOTER_COMPLETE;
+ con->out_msg->footer.front_crc =
+ cpu_to_le32(crc32c(0, m->front.iov_base, m->front.iov_len));
+ if (m->middle)
+ con->out_msg->footer.middle_crc =
+ cpu_to_le32(crc32c(0, m->middle->vec.iov_base,
+ m->middle->vec.iov_len));
+ else
+ con->out_msg->footer.middle_crc = 0;
+ con->out_msg->footer.data_crc = 0;
+ dout("prepare_write_message front_crc %u data_crc %u\n",
+ le32_to_cpu(con->out_msg->footer.front_crc),
+ le32_to_cpu(con->out_msg->footer.middle_crc));
+
+ /* is there a data payload? */
+ if (le32_to_cpu(m->hdr.data_len) > 0) {
+ /* initialize page iterator */
+ con->out_msg_pos.page = 0;
+ con->out_msg_pos.page_pos =
+ le16_to_cpu(m->hdr.data_off) & ~PAGE_MASK;
+ con->out_msg_pos.data_pos = 0;
+ con->out_msg_pos.did_page_crc = 0;
+ con->out_more = 1; /* data + footer will follow */
+ } else {
+ /* no, queue up footer too and be done */
+ prepare_write_message_footer(con, v);
+ }
+
+ set_bit(WRITE_PENDING, &con->state);
+}
+
+/*
+ * 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[0].iov_base = &tag_ack;
+ con->out_kvec[0].iov_len = 1;
+ con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
+ con->out_kvec[1].iov_base = &con->out_temp_ack;
+ con->out_kvec[1].iov_len = sizeof(con->out_temp_ack);
+ con->out_kvec_left = 2;
+ con->out_kvec_bytes = 1 + sizeof(con->out_temp_ack);
+ con->out_kvec_cur = con->out_kvec;
+ con->out_more = 1; /* more will follow.. eventually.. */
+ set_bit(WRITE_PENDING, &con->state);
+}
+
+/*
+ * Prepare to write keepalive byte.
+ */
+static void prepare_write_keepalive(struct ceph_connection *con)
+{
+ dout("prepare_write_keepalive %p\n", con);
+ con->out_kvec[0].iov_base = &tag_keepalive;
+ con->out_kvec[0].iov_len = 1;
+ con->out_kvec_left = 1;
+ con->out_kvec_bytes = 1;
+ con->out_kvec_cur = con->out_kvec;
+ set_bit(WRITE_PENDING, &con->state);
+}
+
+/*
+ * Connection negotiation.
+ */
+
+static void prepare_connect_authorizer(struct ceph_connection *con)
+{
+ void *auth_buf;
+ int auth_len = 0;
+ int auth_protocol = 0;
+
+ mutex_unlock(&con->mutex);
+ if (con->ops->get_authorizer)
+ con->ops->get_authorizer(con, &auth_buf, &auth_len,
+ &auth_protocol, &con->auth_reply_buf,
+ &con->auth_reply_buf_len,
+ con->auth_retry);
+ mutex_lock(&con->mutex);
+
+ con->out_connect.authorizer_protocol = cpu_to_le32(auth_protocol);
+ con->out_connect.authorizer_len = cpu_to_le32(auth_len);
+
+ con->out_kvec[con->out_kvec_left].iov_base = auth_buf;
+ con->out_kvec[con->out_kvec_left].iov_len = auth_len;
+ con->out_kvec_left++;
+ con->out_kvec_bytes += auth_len;
+}
+
+/*
+ * We connected to a peer and are saying hello.
+ */
+static void prepare_write_banner(struct ceph_messenger *msgr,
+ struct ceph_connection *con)
+{
+ int len = strlen(CEPH_BANNER);
+
+ con->out_kvec[0].iov_base = CEPH_BANNER;
+ con->out_kvec[0].iov_len = len;
+ con->out_kvec[1].iov_base = &msgr->my_enc_addr;
+ con->out_kvec[1].iov_len = sizeof(msgr->my_enc_addr);
+ con->out_kvec_left = 2;
+ con->out_kvec_bytes = len + sizeof(msgr->my_enc_addr);
+ con->out_kvec_cur = con->out_kvec;
+ con->out_more = 0;
+ set_bit(WRITE_PENDING, &con->state);
+}
+
+static void prepare_write_connect(struct ceph_messenger *msgr,
+ struct ceph_connection *con,
+ int after_banner)
+{
+ unsigned global_seq = get_global_seq(con->msgr, 0);
+ int proto;
+
+ 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 = CEPH_FEATURE_SUPPORTED;
+ 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;
+
+ if (!after_banner) {
+ con->out_kvec_left = 0;
+ con->out_kvec_bytes = 0;
+ }
+ con->out_kvec[con->out_kvec_left].iov_base = &con->out_connect;
+ con->out_kvec[con->out_kvec_left].iov_len = sizeof(con->out_connect);
+ con->out_kvec_left++;
+ con->out_kvec_bytes += sizeof(con->out_connect);
+ con->out_kvec_cur = con->out_kvec;
+ con->out_more = 0;
+ set_bit(WRITE_PENDING, &con->state);
+
+ prepare_connect_authorizer(con);
+}
+
+
+/*
+ * 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 */
+ while (ret > 0) {
+ if (ret >= con->out_kvec_cur->iov_len) {
+ ret -= con->out_kvec_cur->iov_len;
+ con->out_kvec_cur++;
+ con->out_kvec_left--;
+ } else {
+ con->out_kvec_cur->iov_len -= ret;
+ con->out_kvec_cur->iov_base += ret;
+ ret = 0;
+ break;
+ }
+ }
+ }
+ 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! */
+}
+
+/*
+ * 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_msg_pages(struct ceph_connection *con)
+{
+ struct ceph_msg *msg = con->out_msg;
+ unsigned data_len = le32_to_cpu(msg->hdr.data_len);
+ size_t len;
+ int crc = con->msgr->nocrc;
+ int ret;
+
+ dout("write_partial_msg_pages %p msg %p page %d/%d offset %d\n",
+ con, con->out_msg, con->out_msg_pos.page, con->out_msg->nr_pages,
+ con->out_msg_pos.page_pos);
+
+ while (con->out_msg_pos.page < con->out_msg->nr_pages) {
+ struct page *page = NULL;
+ void *kaddr = NULL;
+
+ /*
+ * if we are calculating the data crc (the default), we need
+ * to map the page. if our pages[] has been revoked, use the
+ * zero page.
+ */
+ if (msg->pages) {
+ page = msg->pages[con->out_msg_pos.page];
+ if (crc)
+ kaddr = kmap(page);
+ } else if (msg->pagelist) {
+ page = list_first_entry(&msg->pagelist->head,
+ struct page, lru);
+ if (crc)
+ kaddr = kmap(page);
+ } else {
+ page = con->msgr->zero_page;
+ if (crc)
+ kaddr = page_address(con->msgr->zero_page);
+ }
+ len = min((int)(PAGE_SIZE - con->out_msg_pos.page_pos),
+ (int)(data_len - con->out_msg_pos.data_pos));
+ if (crc && !con->out_msg_pos.did_page_crc) {
+ void *base = kaddr + con->out_msg_pos.page_pos;
+ u32 tmpcrc = le32_to_cpu(con->out_msg->footer.data_crc);
+
+ BUG_ON(kaddr == NULL);
+ con->out_msg->footer.data_crc =
+ cpu_to_le32(crc32c(tmpcrc, base, len));
+ con->out_msg_pos.did_page_crc = 1;
+ }
+
+ ret = kernel_sendpage(con->sock, page,
+ con->out_msg_pos.page_pos, len,
+ MSG_DONTWAIT | MSG_NOSIGNAL |
+ MSG_MORE);
+
+ if (crc && (msg->pages || msg->pagelist))
+ kunmap(page);
+
+ if (ret <= 0)
+ goto out;
+
+ con->out_msg_pos.data_pos += ret;
+ con->out_msg_pos.page_pos += ret;
+ if (ret == len) {
+ con->out_msg_pos.page_pos = 0;
+ con->out_msg_pos.page++;
+ con->out_msg_pos.did_page_crc = 0;
+ if (msg->pagelist)
+ list_move_tail(&page->lru,
+ &msg->pagelist->head);
+ }
+ }
+
+ dout("write_partial_msg_pages %p msg %p done\n", con, msg);
+
+ /* prepare and queue up footer, too */
+ if (!crc)
+ con->out_msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC;
+ con->out_kvec_bytes = 0;
+ con->out_kvec_left = 0;
+ con->out_kvec_cur = con->out_kvec;
+ prepare_write_message_footer(con, 0);
+ ret = 1;
+out:
+ return ret;
+}
+
+/*
+ * write some zeros
+ */
+static int write_partial_skip(struct ceph_connection *con)
+{
+ int ret;
+
+ while (con->out_skip > 0) {
+ struct kvec iov = {
+ .iov_base = page_address(con->msgr->zero_page),
+ .iov_len = min(con->out_skip, (int)PAGE_CACHE_SIZE)
+ };
+
+ ret = ceph_tcp_sendmsg(con->sock, &iov, 1, iov.iov_len, 1);
+ 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_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 *to, int size, void *object)
+{
+ *to += size;
+ while (con->in_base_pos < *to) {
+ int left = *to - 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 ret, to = 0;
+
+ dout("read_partial_banner %p at %d\n", con, con->in_base_pos);
+
+ /* peer's banner */
+ ret = read_partial(con, &to, strlen(CEPH_BANNER), con->in_banner);
+ if (ret <= 0)
+ goto out;
+ ret = read_partial(con, &to, sizeof(con->actual_peer_addr),
+ &con->actual_peer_addr);
+ if (ret <= 0)
+ goto out;
+ ret = read_partial(con, &to, sizeof(con->peer_addr_for_me),
+ &con->peer_addr_for_me);
+ if (ret <= 0)
+ goto out;
+out:
+ return ret;
+}
+
+static int read_partial_connect(struct ceph_connection *con)
+{
+ int ret, to = 0;
+
+ dout("read_partial_connect %p at %d\n", con, con->in_base_pos);
+
+ ret = read_partial(con, &to, sizeof(con->in_reply), &con->in_reply);
+ if (ret <= 0)
+ goto out;
+ ret = read_partial(con, &to, le32_to_cpu(con->in_reply.authorizer_len),
+ 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",
+ 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);
+ case AF_INET6:
+ ((struct sockaddr_in6 *)ss)->sin6_port = htons(p);
+ }
+}
+
+/*
+ * 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;
+ 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;
+ struct sockaddr_in *in4 = (void *)ss;
+ struct sockaddr_in6 *in6 = (void *)ss;
+ int port;
+
+ memset(ss, 0, sizeof(*ss));
+ if (in4_pton(p, end - p, (u8 *)&in4->sin_addr.s_addr,
+ ',', &ipend)) {
+ ss->ss_family = AF_INET;
+ } else if (in6_pton(p, end - p, (u8 *)&in6->sin6_addr.s6_addr,
+ ',', &ipend)) {
+ ss->ss_family = AF_INET6;
+ } else {
+ goto bad;
+ }
+ p = ipend;
+
+ /* port? */
+ if (p < end && *p == ':') {
+ port = 0;
+ p++;
+ while (p < end && *p >= '0' && *p <= '9') {
+ port = (port * 10) + (*p - '0');
+ p++;
+ }
+ if (port > 65535 || port == 0)
+ goto bad;
+ } else {
+ port = CEPH_MON_PORT;
+ }
+
+ addr_set_port(ss, port);
+
+ dout("parse_ips got %s\n", 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", c);
+ return -EINVAL;
+}
+
+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_warning("wrong peer, want %s/%lld, got %s/%lld\n",
+ pr_addr(&con->peer_addr.in_addr),
+ le64_to_cpu(con->peer_addr.nonce),
+ pr_addr(&con->actual_peer_addr.in_addr),
+ le64_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",
+ pr_addr(&con->msgr->inst.addr.in_addr));
+ }
+
+ set_bit(NEGOTIATING, &con->state);
+ prepare_read_connect(con);
+ return 0;
+}
+
+static void fail_protocol(struct ceph_connection *con)
+{
+ reset_connection(con);
+ set_bit(CLOSED, &con->state); /* in case there's queued work */
+
+ mutex_unlock(&con->mutex);
+ if (con->ops->bad_proto)
+ con->ops->bad_proto(con);
+ mutex_lock(&con->mutex);
+}
+
+static int process_connect(struct ceph_connection *con)
+{
+ u64 sup_feat = CEPH_FEATURE_SUPPORTED;
+ u64 req_feat = CEPH_FEATURE_REQUIRED;
+ u64 server_feat = le64_to_cpu(con->in_reply.features);
+
+ 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),
+ pr_addr(&con->peer_addr.in_addr),
+ sup_feat, server_feat, server_feat & ~sup_feat);
+ con->error_msg = "missing required protocol features";
+ fail_protocol(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),
+ 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";
+ fail_protocol(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";
+ reset_connection(con);
+ set_bit(CLOSED, &con->state);
+ return -1;
+ }
+ con->auth_retry = 1;
+ prepare_write_connect(con->msgr, con, 0);
+ 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_connect.connect_seq));
+ pr_err("%s%lld %s connection reset\n",
+ ENTITY_NAME(con->peer_name),
+ pr_addr(&con->peer_addr.in_addr));
+ reset_connection(con);
+ prepare_write_connect(con->msgr, con, 0);
+ 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);
+ 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 my seq = %u, peer_seq = %u\n",
+ le32_to_cpu(con->out_connect.connect_seq),
+ le32_to_cpu(con->in_connect.connect_seq));
+ con->connect_seq = le32_to_cpu(con->in_connect.connect_seq);
+ prepare_write_connect(con->msgr, con, 0);
+ 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_connect.global_seq));
+ get_global_seq(con->msgr,
+ le32_to_cpu(con->in_connect.global_seq));
+ prepare_write_connect(con->msgr, con, 0);
+ prepare_read_connect(con);
+ break;
+
+ 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),
+ pr_addr(&con->peer_addr.in_addr),
+ req_feat, server_feat, req_feat & ~server_feat);
+ con->error_msg = "missing required protocol features";
+ fail_protocol(con);
+ return -1;
+ }
+ clear_bit(CONNECTING, &con->state);
+ con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq);
+ con->connect_seq++;
+ 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)
+ set_bit(LOSSYTX, &con->state);
+
+ 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.
+ */
+ pr_err("process_connect peer connecting WAIT\n");
+
+ default:
+ pr_err("connect protocol error, will retry\n");
+ 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 to = 0;
+
+ return read_partial(con, &to, sizeof(con->in_temp_ack),
+ &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);
+ 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 left;
+ int ret;
+
+ 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 struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
+ struct ceph_msg_header *hdr,
+ int *skip);
+/*
+ * read (part of) a message.
+ */
+static int read_partial_message(struct ceph_connection *con)
+{
+ struct ceph_msg *m = con->in_msg;
+ void *p;
+ int ret;
+ int to, left;
+ unsigned front_len, middle_len, data_len, data_off;
+ int datacrc = con->msgr->nocrc;
+ int skip;
+ u64 seq;
+
+ dout("read_partial_message con %p msg %p\n", con, m);
+
+ /* header */
+ while (con->in_base_pos < sizeof(con->in_hdr)) {
+ left = sizeof(con->in_hdr) - con->in_base_pos;
+ ret = ceph_tcp_recvmsg(con->sock,
+ (char *)&con->in_hdr + con->in_base_pos,
+ left);
+ if (ret <= 0)
+ return ret;
+ con->in_base_pos += ret;
+ if (con->in_base_pos == sizeof(con->in_hdr)) {
+ u32 crc = crc32c(0, (void *)&con->in_hdr,
+ sizeof(con->in_hdr) - sizeof(con->in_hdr.crc));
+ if (crc != le32_to_cpu(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_DATA_LEN)
+ return -EIO;
+ data_len = le32_to_cpu(con->in_hdr.data_len);
+ if (data_len > CEPH_MSG_MAX_DATA_LEN)
+ return -EIO;
+ data_off = le16_to_cpu(con->in_hdr.data_off);
+
+ /* 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),
+ 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;
+ con->in_seq++;
+ 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 -EBADMSG;
+ }
+
+ /* allocate message? */
+ if (!con->in_msg) {
+ dout("got hdr type %d front %d data %d\n", con->in_hdr.type,
+ con->in_hdr.front_len, con->in_hdr.data_len);
+ con->in_msg = ceph_alloc_msg(con, &con->in_hdr, &skip);
+ if (skip) {
+ /* skip this message */
+ dout("alloc_msg returned NULL, skipping 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;
+ }
+ if (IS_ERR(con->in_msg)) {
+ ret = PTR_ERR(con->in_msg);
+ con->in_msg = NULL;
+ con->error_msg =
+ "error allocating memory for incoming message";
+ return ret;
+ }
+ m = con->in_msg;
+ m->front.iov_len = 0; /* haven't read it yet */
+ if (m->middle)
+ m->middle->vec.iov_len = 0;
+
+ con->in_msg_pos.page = 0;
+ con->in_msg_pos.page_pos = data_off & ~PAGE_MASK;
+ con->in_msg_pos.data_pos = 0;
+ }
+
+ /* 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 */
+ while (con->in_msg_pos.data_pos < data_len) {
+ left = min((int)(data_len - con->in_msg_pos.data_pos),
+ (int)(PAGE_SIZE - con->in_msg_pos.page_pos));
+ BUG_ON(m->pages == NULL);
+ p = kmap(m->pages[con->in_msg_pos.page]);
+ ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
+ left);
+ if (ret > 0 && datacrc)
+ con->in_data_crc =
+ crc32c(con->in_data_crc,
+ p + con->in_msg_pos.page_pos, ret);
+ kunmap(m->pages[con->in_msg_pos.page]);
+ if (ret <= 0)
+ return ret;
+ con->in_msg_pos.data_pos += ret;
+ con->in_msg_pos.page_pos += ret;
+ if (con->in_msg_pos.page_pos == PAGE_SIZE) {
+ con->in_msg_pos.page_pos = 0;
+ con->in_msg_pos.page++;
+ }
+ }
+
+ /* footer */
+ to = sizeof(m->hdr) + sizeof(m->footer);
+ while (con->in_base_pos < to) {
+ left = to - con->in_base_pos;
+ ret = ceph_tcp_recvmsg(con->sock, (char *)&m->footer +
+ (con->in_base_pos - sizeof(m->hdr)),
+ left);
+ if (ret <= 0)
+ return ret;
+ con->in_base_pos += ret;
+ }
+ 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 (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;
+ }
+
+ 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;
+
+ msg = con->in_msg;
+ con->in_msg = NULL;
+
+ /* if first message, set peer_name */
+ if (con->peer_name.type == 0)
+ con->peer_name = msg->hdr.src.name;
+
+ 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.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.data_len),
+ con->in_front_crc, con->in_middle_crc, con->in_data_crc);
+ con->ops->dispatch(con, msg);
+
+ mutex_lock(&con->mutex);
+ prepare_read_tag(con);
+}
+
+
+/*
+ * 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)
+{
+ struct ceph_messenger *msgr = con->msgr;
+ int ret = 1;
+
+ dout("try_write start %p state %lu nref %d\n", con, con->state,
+ atomic_read(&con->nref));
+
+ mutex_lock(&con->mutex);
+more:
+ dout("try_write out_kvec_bytes %d\n", con->out_kvec_bytes);
+
+ /* open the socket first? */
+ if (con->sock == NULL) {
+ /*
+ * if we were STANDBY and are reconnecting _this_
+ * connection, bump connect_seq now. Always bump
+ * global_seq.
+ */
+ if (test_and_clear_bit(STANDBY, &con->state))
+ con->connect_seq++;
+
+ prepare_write_banner(msgr, con);
+ prepare_write_connect(msgr, con, 1);
+ prepare_read_banner(con);
+ set_bit(CONNECTING, &con->state);
+ clear_bit(NEGOTIATING, &con->state);
+
+ 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);
+ con->sock = ceph_tcp_connect(con);
+ if (IS_ERR(con->sock)) {
+ con->sock = NULL;
+ con->error_msg = "connect error";
+ ret = -1;
+ goto out;
+ }
+ }
+
+more_kvec:
+ /* kvec data queued? */
+ if (con->out_skip) {
+ ret = write_partial_skip(con);
+ if (ret <= 0)
+ goto done;
+ if (ret < 0) {
+ dout("try_write write_partial_skip err %d\n", ret);
+ goto done;
+ }
+ }
+ if (con->out_kvec_left) {
+ ret = write_partial_kvec(con);
+ if (ret <= 0)
+ goto done;
+ }
+
+ /* 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_msg_pages(con);
+ if (ret == 1)
+ goto more_kvec; /* we need to send the footer, too! */
+ if (ret == 0)
+ goto done;
+ if (ret < 0) {
+ dout("try_write write_partial_msg_pages err %d\n",
+ ret);
+ goto done;
+ }
+ }
+
+do_next:
+ if (!test_bit(CONNECTING, &con->state)) {
+ /* 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 (test_and_clear_bit(KEEPALIVE_PENDING, &con->state)) {
+ prepare_write_keepalive(con);
+ goto more;
+ }
+ }
+
+ /* Nothing to do! */
+ clear_bit(WRITE_PENDING, &con->state);
+ dout("try_write nothing else to write.\n");
+done:
+ ret = 0;
+out:
+ mutex_unlock(&con->mutex);
+ dout("try_write done on %p\n", con);
+ return ret;
+}
+
+
+
+/*
+ * Read what we can from the socket.
+ */
+static int try_read(struct ceph_connection *con)
+{
+ struct ceph_messenger *msgr;
+ int ret = -1;
+
+ if (!con->sock)
+ return 0;
+
+ if (test_bit(STANDBY, &con->state))
+ return 0;
+
+ dout("try_read start on %p\n", con);
+ msgr = con->msgr;
+
+ mutex_lock(&con->mutex);
+
+more:
+ dout("try_read tag %d in_base_pos %d\n", (int)con->in_tag,
+ con->in_base_pos);
+ if (test_bit(CONNECTING, &con->state)) {
+ if (!test_bit(NEGOTIATING, &con->state)) {
+ dout("try_read connecting\n");
+ ret = read_partial_banner(con);
+ if (ret <= 0)
+ goto done;
+ if (process_banner(con) < 0) {
+ ret = -1;
+ goto out;
+ }
+ }
+ ret = read_partial_connect(con);
+ if (ret <= 0)
+ goto done;
+ if (process_connect(con) < 0) {
+ ret = -1;
+ goto out;
+ }
+ goto more;
+ }
+
+ if (con->in_base_pos < 0) {
+ /*
+ * skipping + discarding content.
+ *
+ * FIXME: there must be a better way to do this!
+ */
+ static char buf[1024];
+ int skip = min(1024, -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 done;
+ 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 done;
+ 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:
+ set_bit(CLOSED, &con->state); /* fixme */
+ goto done;
+ 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";
+ ret = -EIO;
+ goto out;
+ case -EIO:
+ con->error_msg = "io error";
+ goto out;
+ default:
+ goto done;
+ }
+ }
+ if (con->in_tag == CEPH_MSGR_TAG_READY)
+ goto more;
+ process_message(con);
+ goto more;
+ }
+ if (con->in_tag == CEPH_MSGR_TAG_ACK) {
+ ret = read_partial_ack(con);
+ if (ret <= 0)
+ goto done;
+ process_ack(con);
+ goto more;
+ }
+
+done:
+ ret = 0;
+out:
+ mutex_unlock(&con->mutex);
+ dout("try_read done on %p\n", con);
+ 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. Bump @con reference to
+ * avoid races with connection teardown.
+ *
+ * There is some trickery going on with QUEUED and BUSY because we
+ * only want a _single_ thread operating on each connection at any
+ * point in time, but we want to use all available CPUs.
+ *
+ * The worker thread only proceeds if it can atomically set BUSY. It
+ * clears QUEUED and does it's thing. When it thinks it's done, it
+ * clears BUSY, then rechecks QUEUED.. if it's set again, it loops
+ * (tries again to set BUSY).
+ *
+ * To queue work, we first set QUEUED, _then_ if BUSY isn't set, we
+ * try to queue work. If that fails (work is already queued, or BUSY)
+ * we give up (work also already being done or is queued) but leave QUEUED
+ * set so that the worker thread will loop if necessary.
+ */
+static void queue_con(struct ceph_connection *con)
+{
+ if (test_bit(DEAD, &con->state)) {
+ dout("queue_con %p ignoring: DEAD\n",
+ con);
+ return;
+ }
+
+ if (!con->ops->get(con)) {
+ dout("queue_con %p ref count 0\n", con);
+ return;
+ }
+
+ set_bit(QUEUED, &con->state);
+ if (test_bit(BUSY, &con->state)) {
+ dout("queue_con %p - already BUSY\n", con);
+ con->ops->put(con);
+ } else if (!queue_work(ceph_msgr_wq, &con->work.work)) {
+ dout("queue_con %p - already queued\n", con);
+ con->ops->put(con);
+ } else {
+ dout("queue_con %p\n", 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);
+ int backoff = 0;
+
+more:
+ if (test_and_set_bit(BUSY, &con->state) != 0) {
+ dout("con_work %p BUSY already set\n", con);
+ goto out;
+ }
+ dout("con_work %p start, clearing QUEUED\n", con);
+ clear_bit(QUEUED, &con->state);
+
+ if (test_bit(CLOSED, &con->state)) { /* e.g. if we are replaced */
+ dout("con_work CLOSED\n");
+ con_close_socket(con);
+ goto done;
+ }
+ if (test_and_clear_bit(OPENING, &con->state)) {
+ /* reopen w/ new peer */
+ dout("con_work OPENING\n");
+ con_close_socket(con);
+ }
+
+ if (test_and_clear_bit(SOCK_CLOSED, &con->state) ||
+ try_read(con) < 0 ||
+ try_write(con) < 0) {
+ backoff = 1;
+ ceph_fault(con); /* error/fault path */
+ }
+
+done:
+ clear_bit(BUSY, &con->state);
+ dout("con->state=%lu\n", con->state);
+ if (test_bit(QUEUED, &con->state)) {
+ if (!backoff || test_bit(OPENING, &con->state)) {
+ dout("con_work %p QUEUED reset, looping\n", con);
+ goto more;
+ }
+ dout("con_work %p QUEUED reset, but just faulted\n", con);
+ clear_bit(QUEUED, &con->state);
+ }
+ dout("con_work %p done\n", con);
+
+out:
+ con->ops->put(con);
+}
+
+
+/*
+ * Generic error/fault handler. A retry mechanism is used with
+ * exponential backoff
+ */
+static void ceph_fault(struct ceph_connection *con)
+{
+ pr_err("%s%lld %s %s\n", ENTITY_NAME(con->peer_name),
+ pr_addr(&con->peer_addr.in_addr), con->error_msg);
+ dout("fault %p state %lu to peer %s\n",
+ con, con->state, pr_addr(&con->peer_addr.in_addr));
+
+ if (test_bit(LOSSYTX, &con->state)) {
+ dout("fault on LOSSYTX channel\n");
+ goto out;
+ }
+
+ mutex_lock(&con->mutex);
+ if (test_bit(CLOSED, &con->state))
+ goto out_unlock;
+
+ con_close_socket(con);
+
+ if (con->in_msg) {
+ ceph_msg_put(con->in_msg);
+ con->in_msg = NULL;
+ }
+
+ /* Requeue anything that hasn't been acked */
+ list_splice_init(&con->out_sent, &con->out_queue);
+
+ /* If there are no messages in the queue, place the connection
+ * in a STANDBY state (i.e., don't try to reconnect just yet). */
+ if (list_empty(&con->out_queue) && !con->out_keepalive_pending) {
+ dout("fault setting STANDBY\n");
+ set_bit(STANDBY, &con->state);
+ } else {
+ /* retry after a delay. */
+ if (con->delay == 0)
+ con->delay = BASE_DELAY_INTERVAL;
+ else if (con->delay < MAX_DELAY_INTERVAL)
+ con->delay *= 2;
+ dout("fault queueing %p delay %lu\n", con, con->delay);
+ con->ops->get(con);
+ if (queue_delayed_work(ceph_msgr_wq, &con->work,
+ round_jiffies_relative(con->delay)) == 0)
+ con->ops->put(con);
+ }
+
+out_unlock:
+ mutex_unlock(&con->mutex);
+out:
+ /*
+ * 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);
+}
+
+
+
+/*
+ * create a new messenger instance
+ */
+struct ceph_messenger *ceph_messenger_create(struct ceph_entity_addr *myaddr)
+{
+ struct ceph_messenger *msgr;
+
+ msgr = kzalloc(sizeof(*msgr), GFP_KERNEL);
+ if (msgr == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ spin_lock_init(&msgr->global_seq_lock);
+
+ /* the zero page is needed if a request is "canceled" while the message
+ * is being written over the socket */
+ msgr->zero_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ if (!msgr->zero_page) {
+ kfree(msgr);
+ return ERR_PTR(-ENOMEM);
+ }
+ kmap(msgr->zero_page);
+
+ 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);
+
+ dout("messenger_create %p\n", msgr);
+ return msgr;
+}
+
+void ceph_messenger_destroy(struct ceph_messenger *msgr)
+{
+ dout("destroy %p\n", msgr);
+ kunmap(msgr->zero_page);
+ __free_page(msgr->zero_page);
+ kfree(msgr);
+ dout("destroyed messenger %p\n", msgr);
+}
+
+/*
+ * Queue up an outgoing message on the given connection.
+ */
+void ceph_con_send(struct ceph_connection *con, struct ceph_msg *msg)
+{
+ if (test_bit(CLOSED, &con->state)) {
+ dout("con_send %p closed, dropping %p\n", con, msg);
+ ceph_msg_put(msg);
+ return;
+ }
+
+ /* set src+dst */
+ msg->hdr.src.name = con->msgr->inst.name;
+ msg->hdr.src.addr = con->msgr->my_enc_addr;
+ msg->hdr.orig_src = msg->hdr.src;
+
+ BUG_ON(msg->front.iov_len != le32_to_cpu(msg->hdr.front_len));
+
+ /* queue */
+ mutex_lock(&con->mutex);
+ 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));
+ mutex_unlock(&con->mutex);
+
+ /* if there wasn't anything waiting to send before, queue
+ * new work */
+ if (test_and_set_bit(WRITE_PENDING, &con->state) == 0)
+ queue_con(con);
+}
+
+/*
+ * Revoke a message that was previously queued for send
+ */
+void ceph_con_revoke(struct ceph_connection *con, struct ceph_msg *msg)
+{
+ mutex_lock(&con->mutex);
+ if (!list_empty(&msg->list_head)) {
+ dout("con_revoke %p msg %p\n", con, msg);
+ list_del_init(&msg->list_head);
+ ceph_msg_put(msg);
+ msg->hdr.seq = 0;
+ if (con->out_msg == msg) {
+ ceph_msg_put(con->out_msg);
+ con->out_msg = NULL;
+ }
+ if (con->out_kvec_is_msg) {
+ con->out_skip = con->out_kvec_bytes;
+ con->out_kvec_is_msg = false;
+ }
+ } else {
+ dout("con_revoke %p msg %p - not queued (sent?)\n", con, msg);
+ }
+ mutex_unlock(&con->mutex);
+}
+
+/*
+ * Revoke a message that we may be reading data into
+ */
+void ceph_con_revoke_message(struct ceph_connection *con, struct ceph_msg *msg)
+{
+ mutex_lock(&con->mutex);
+ if (con->in_msg && con->in_msg == msg) {
+ unsigned front_len = le32_to_cpu(con->in_hdr.front_len);
+ unsigned middle_len = le32_to_cpu(con->in_hdr.middle_len);
+ unsigned data_len = le32_to_cpu(con->in_hdr.data_len);
+
+ /* skip rest of message */
+ dout("con_revoke_pages %p msg %p revoked\n", 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("con_revoke_pages %p msg %p pages %p no-op\n",
+ 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)
+{
+ if (test_and_set_bit(KEEPALIVE_PENDING, &con->state) == 0 &&
+ test_and_set_bit(WRITE_PENDING, &con->state) == 0)
+ queue_con(con);
+}
+
+
+/*
+ * 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,
+ int page_len, int page_off, struct page **pages)
+{
+ struct ceph_msg *m;
+
+ m = kmalloc(sizeof(*m), GFP_NOFS);
+ if (m == NULL)
+ goto out;
+ kref_init(&m->kref);
+ INIT_LIST_HEAD(&m->list_head);
+
+ m->hdr.type = cpu_to_le16(type);
+ m->hdr.front_len = cpu_to_le32(front_len);
+ m->hdr.middle_len = 0;
+ m->hdr.data_len = cpu_to_le32(page_len);
+ m->hdr.data_off = cpu_to_le16(page_off);
+ m->hdr.priority = cpu_to_le16(CEPH_MSG_PRIO_DEFAULT);
+ m->footer.front_crc = 0;
+ m->footer.middle_crc = 0;
+ m->footer.data_crc = 0;
+ m->front_max = front_len;
+ m->front_is_vmalloc = false;
+ m->more_to_follow = false;
+ m->pool = NULL;
+
+ /* front */
+ if (front_len) {
+ if (front_len > PAGE_CACHE_SIZE) {
+ m->front.iov_base = __vmalloc(front_len, GFP_NOFS,
+ PAGE_KERNEL);
+ m->front_is_vmalloc = true;
+ } else {
+ m->front.iov_base = kmalloc(front_len, GFP_NOFS);
+ }
+ if (m->front.iov_base == NULL) {
+ pr_err("msg_new can't allocate %d bytes\n",
+ front_len);
+ goto out2;
+ }
+ } else {
+ m->front.iov_base = NULL;
+ }
+ m->front.iov_len = front_len;
+
+ /* middle */
+ m->middle = NULL;
+
+ /* data */
+ m->nr_pages = calc_pages_for(page_off, page_len);
+ m->pages = pages;
+ m->pagelist = NULL;
+
+ dout("ceph_msg_new %p page %d~%d -> %d\n", m, page_off, page_len,
+ m->nr_pages);
+ return m;
+
+out2:
+ ceph_msg_put(m);
+out:
+ pr_err("msg_new can't create type %d len %d\n", type, front_len);
+ return ERR_PTR(-ENOMEM);
+}
+
+/*
+ * 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;
+}
+
+/*
+ * Generic message allocator, for incoming messages.
+ */
+static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
+ struct ceph_msg_header *hdr,
+ int *skip)
+{
+ int type = le16_to_cpu(hdr->type);
+ int front_len = le32_to_cpu(hdr->front_len);
+ int middle_len = le32_to_cpu(hdr->middle_len);
+ struct ceph_msg *msg = NULL;
+ int ret;
+
+ if (con->ops->alloc_msg) {
+ mutex_unlock(&con->mutex);
+ msg = con->ops->alloc_msg(con, hdr, skip);
+ mutex_lock(&con->mutex);
+ if (IS_ERR(msg))
+ return msg;
+
+ if (*skip)
+ return NULL;
+ }
+ if (!msg) {
+ *skip = 0;
+ msg = ceph_msg_new(type, front_len, 0, 0, NULL);
+ if (!msg) {
+ pr_err("unable to allocate msg type %d len %d\n",
+ type, front_len);
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+ memcpy(&msg->hdr, &con->in_hdr, sizeof(con->in_hdr));
+
+ if (middle_len) {
+ ret = ceph_alloc_middle(con, msg);
+
+ if (ret < 0) {
+ ceph_msg_put(msg);
+ return msg;
+ }
+ }
+
+ return msg;
+}
+
+
+/*
+ * Free a generically kmalloc'd message.
+ */
+void ceph_msg_kfree(struct ceph_msg *m)
+{
+ dout("msg_kfree %p\n", m);
+ if (m->front_is_vmalloc)
+ vfree(m->front.iov_base);
+ else
+ kfree(m->front.iov_base);
+ kfree(m);
+}
+
+/*
+ * Drop a msg ref. Destroy as needed.
+ */
+void ceph_msg_last_put(struct kref *kref)
+{
+ struct ceph_msg *m = container_of(kref, struct ceph_msg, kref);
+
+ dout("ceph_msg_put last one on %p\n", m);
+ WARN_ON(!list_empty(&m->list_head));
+
+ /* drop middle, data, if any */
+ if (m->middle) {
+ ceph_buffer_put(m->middle);
+ m->middle = NULL;
+ }
+ m->nr_pages = 0;
+ m->pages = NULL;
+
+ if (m->pagelist) {
+ ceph_pagelist_release(m->pagelist);
+ kfree(m->pagelist);
+ m->pagelist = NULL;
+ }
+
+ if (m->pool)
+ ceph_msgpool_put(m->pool, m);
+ else
+ ceph_msg_kfree(m);
+}
+
+void ceph_msg_dump(struct ceph_msg *msg)
+{
+ pr_debug("msg_dump %p (front_max %d nr_pages %d)\n", msg,
+ msg->front_max, msg->nr_pages);
+ 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);
+}