linux/fs/ceph/messenger.c

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51 KiB
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#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/socket.h>
#include <linux/string.h>
#include <net/tcp.h>
#include "super.h"
#include "messenger.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;
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;
}
/*
* 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;
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 */
mutex_lock(&con->out_mutex);
ceph_msg_remove_list(&con->out_queue);
ceph_msg_remove_list(&con->out_sent);
con->connect_seq = 0;
con->out_seq = 0;
con->out_msg = NULL;
con->in_seq = 0;
mutex_unlock(&con->out_mutex);
}
/*
* 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 */
reset_connection(con);
queue_con(con);
}
/*
* clean up connection state
*/
void ceph_con_shutdown(struct ceph_connection *con)
{
dout("con_shutdown %p\n", con);
reset_connection(con);
set_bit(DEAD, &con->state);
con_close_socket(con); /* silently ignore errors */
}
/*
* 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));
queue_con(con);
}
/*
* 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)) {
ceph_con_shutdown(con);
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->out_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 = NULL; /* we're done with this one */
}
/*
* 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;
/* 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);
}
/* move message to sending/sent list */
m = list_first_entry(&con->out_queue,
struct ceph_msg, list_head);
list_move_tail(&m->list_head, &con->out_sent);
con->out_msg = m; /* we don't bother taking a reference here. */
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.
*/
/*
* We connected to a peer and are saying hello.
*/
static void prepare_write_connect(struct ceph_messenger *msgr,
struct ceph_connection *con)
{
int len = strlen(CEPH_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.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 (test_bit(LOSSYTX, &con->state))
con->out_connect.flags = CEPH_MSG_CONNECT_LOSSY;
con->out_kvec[0].iov_base = CEPH_BANNER;
con->out_kvec[0].iov_len = len;
con->out_kvec[1].iov_base = &msgr->inst.addr;
con->out_kvec[1].iov_len = sizeof(msgr->inst.addr);
con->out_kvec[2].iov_base = &con->out_connect;
con->out_kvec[2].iov_len = sizeof(con->out_connect);
con->out_kvec_left = 3;
con->out_kvec_bytes = len + sizeof(msgr->inst.addr) +
sizeof(con->out_connect);
con->out_kvec_cur = con->out_kvec;
con->out_more = 0;
set_bit(WRITE_PENDING, &con->state);
}
static void prepare_write_connect_retry(struct ceph_messenger *msgr,
struct ceph_connection *con)
{
dout("prepare_write_connect_retry %p\n", con);
con->out_connect.connect_seq = cpu_to_le32(con->connect_seq);
con->out_connect.global_seq =
cpu_to_le32(get_global_seq(con->msgr, 0));
con->out_kvec[0].iov_base = &con->out_connect;
con->out_kvec[0].iov_len = sizeof(con->out_connect);
con->out_kvec_left = 1;
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);
}
/*
* 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 {
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)
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;
}
}
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_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_connect(struct ceph_connection *con)
{
int ret, to = 0;
dout("read_partial_connect %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;
ret = read_partial(con, &to, sizeof(con->in_reply), &con->in_reply);
if (ret <= 0)
goto out;
dout("read_partial_connect %p connect_seq = %u, global_seq = %u\n",
con, 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/from %s has 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 ((struct sockaddr_in *)ss)->sin_port;
case AF_INET6:
return ((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_connect(struct ceph_connection *con)
{
dout("process_connect on %p tag %d\n", con, (int)con->in_tag);
if (verify_hello(con) < 0)
return -1;
/*
* 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 (!ceph_entity_addr_is_local(&con->peer_addr,
&con->actual_peer_addr) &&
!(addr_is_blank(&con->actual_peer_addr.in_addr) &&
con->actual_peer_addr.nonce == con->peer_addr.nonce)) {
pr_err("wrong peer, want %s/%d, "
"got %s/%d, wtf\n",
pr_addr(&con->peer_addr.in_addr),
con->peer_addr.nonce,
pr_addr(&con->actual_peer_addr.in_addr),
con->actual_peer_addr.nonce);
con->error_msg = "protocol error, wrong peer";
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);
dout("process_connect learned my addr is %s\n",
pr_addr(&con->msgr->inst.addr.in_addr));
}
switch (con->in_reply.tag) {
case CEPH_MSGR_TAG_BADPROTOVER:
dout("process_connect got BADPROTOVER my %d != their %d\n",
le32_to_cpu(con->out_connect.protocol_version),
le32_to_cpu(con->in_reply.protocol_version));
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";
if (con->ops->bad_proto)
con->ops->bad_proto(con);
reset_connection(con);
set_bit(CLOSED, &con->state); /* in case there's queued work */
return -1;
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_retry(con->msgr, con);
prepare_read_connect(con);
/* Tell ceph about it. */
pr_info("reset on %s%lld\n", ENTITY_NAME(con->peer_name));
if (con->ops->peer_reset)
con->ops->peer_reset(con);
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_retry(con->msgr, con);
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_retry(con->msgr, con);
prepare_read_connect(con);
break;
case CEPH_MSGR_TAG_READY:
clear_bit(CONNECTING, &con->state);
if (con->in_reply.flags & CEPH_MSG_CONNECT_LOSSY)
set_bit(LOSSYRX, &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));
con->delay = 0; /* reset backoff memory */
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;
mutex_lock(&con->out_mutex);
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);
}
mutex_unlock(&con->out_mutex);
prepare_read_tag(con);
}
/*
* 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, want, left;
unsigned front_len, middle_len, data_len, data_off;
int datacrc = con->msgr->nocrc;
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;
/* 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 = con->ops->alloc_msg(con, &con->in_hdr);
if (!con->in_msg) {
/* 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;
return 0;
}
if (IS_ERR(con->in_msg)) {
ret = PTR_ERR(con->in_msg);
con->in_msg = NULL;
con->error_msg = "out of memory for incoming message";
return ret;
}
m = con->in_msg;
m->front.iov_len = 0; /* haven't read it yet */
memcpy(&m->hdr, &con->in_hdr, sizeof(con->in_hdr));
}
/* front */
while (m->front.iov_len < front_len) {
BUG_ON(m->front.iov_base == NULL);
left = front_len - m->front.iov_len;
ret = ceph_tcp_recvmsg(con->sock, (char *)m->front.iov_base +
m->front.iov_len, left);
if (ret <= 0)
return ret;
m->front.iov_len += ret;
if (m->front.iov_len == front_len)
con->in_front_crc = crc32c(0, m->front.iov_base,
m->front.iov_len);
}
/* middle */
while (middle_len > 0 && (!m->middle ||
m->middle->vec.iov_len < middle_len)) {
if (m->middle == NULL) {
ret = -EOPNOTSUPP;
if (con->ops->alloc_middle)
ret = con->ops->alloc_middle(con, m);
if (ret < 0) {
dout("alloc_middle failed, skipping payload\n");
con->in_base_pos = -middle_len - data_len
- sizeof(m->footer);
ceph_msg_put(con->in_msg);
con->in_msg = NULL;
con->in_tag = CEPH_MSGR_TAG_READY;
return 0;
}
m->middle->vec.iov_len = 0;
}
left = middle_len - m->middle->vec.iov_len;
ret = ceph_tcp_recvmsg(con->sock,
(char *)m->middle->vec.iov_base +
m->middle->vec.iov_len, left);
if (ret <= 0)
return ret;
m->middle->vec.iov_len += ret;
if (m->middle->vec.iov_len == middle_len)
con->in_middle_crc = crc32c(0, m->middle->vec.iov_base,
m->middle->vec.iov_len);
}
/* (page) data */
data_off = le16_to_cpu(m->hdr.data_off);
if (data_len == 0)
goto no_data;
if (m->nr_pages == 0) {
con->in_msg_pos.page = 0;
con->in_msg_pos.page_pos = data_off & ~PAGE_MASK;
con->in_msg_pos.data_pos = 0;
/* find pages for data payload */
want = calc_pages_for(data_off & ~PAGE_MASK, data_len);
ret = -1;
if (con->ops->prepare_pages)
ret = con->ops->prepare_pages(con, m, want);
if (ret < 0) {
dout("%p prepare_pages failed, skipping payload\n", m);
con->in_base_pos = -data_len - sizeof(m->footer);
ceph_msg_put(con->in_msg);
con->in_msg = NULL;
con->in_tag = CEPH_MSGR_TAG_READY;
return 0;
}
BUG_ON(m->nr_pages < want);
}
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++;
}
}
no_data:
/* 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 = 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;
mutex_lock(&con->out_mutex);
con->in_seq++;
mutex_unlock(&con->out_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);
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->out_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_connect(msgr, con);
prepare_read_connect(con);
set_bit(CONNECTING, &con->state);
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;
if (ret < 0) {
dout("try_write write_partial_kvec err %d\n", ret);
goto done;
}
}
/* msg pages? */
if (con->out_msg) {
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;
}
}
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->out_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;
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)) {
dout("try_read connecting\n");
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:
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) {
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;
}
clear_bit(BUSY, &con->state); /* to avoid an improbable race */
con_close_socket(con);
con->in_msg = NULL;
/* If there are no messages in the queue, place the connection
* in a STANDBY state (i.e., don't try to reconnect just yet). */
mutex_lock(&con->out_mutex);
if (list_empty(&con->out_queue) && !con->out_keepalive_pending) {
dout("fault setting STANDBY\n");
set_bit(STANDBY, &con->state);
mutex_unlock(&con->out_mutex);
goto out;
}
/* Requeue anything that hasn't been acked, and retry after a
* delay. */
list_splice_init(&con->out_sent, &con->out_queue);
mutex_unlock(&con->out_mutex);
if (con->delay == 0)
con->delay = BASE_DELAY_INTERVAL;
else if (con->delay < MAX_DELAY_INTERVAL)
con->delay *= 2;
/* explicitly schedule work to try to reconnect again later. */
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:
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 */
get_random_bytes(&msgr->inst.addr.nonce,
sizeof(msgr->inst.addr.nonce));
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 = con->msgr->inst;
msg->hdr.orig_src = con->msgr->inst;
msg->hdr.dst_erank = con->peer_addr.erank;
/* queue */
mutex_lock(&con->out_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->out_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->out_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)
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->out_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;
atomic_set(&m->nref, 1);
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;
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);
}
/*
* Generic message allocator, for incoming messages.
*/
struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con,
struct ceph_msg_header *hdr)
{
int type = le16_to_cpu(hdr->type);
int front_len = le32_to_cpu(hdr->front_len);
struct ceph_msg *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);
}
return msg;
}
/*
* 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.
*/
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_alloc(middle_len, GFP_NOFS);
if (!msg->middle)
return -ENOMEM;
return 0;
}
/*
* 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_put(struct ceph_msg *m)
{
dout("ceph_msg_put %p %d -> %d\n", m, atomic_read(&m->nref),
atomic_read(&m->nref)-1);
if (atomic_read(&m->nref) <= 0) {
pr_err("bad ceph_msg_put on %p %llu %d=%s %d+%d\n",
m, le64_to_cpu(m->hdr.seq),
le16_to_cpu(m->hdr.type),
ceph_msg_type_name(le16_to_cpu(m->hdr.type)),
le32_to_cpu(m->hdr.front_len),
le32_to_cpu(m->hdr.data_len));
WARN_ON(1);
}
if (atomic_dec_and_test(&m->nref)) {
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->pool)
ceph_msgpool_put(m->pool, m);
else
ceph_msg_kfree(m);
}
}