diff options
Diffstat (limited to 'net/ceph/messenger.c')
| -rw-r--r-- | net/ceph/messenger.c | 2601 |
1 files changed, 2601 insertions, 0 deletions
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c new file mode 100644 index 00000000..f0993af2 --- /dev/null +++ b/net/ceph/messenger.c @@ -0,0 +1,2601 @@ +#include <linux/ceph/ceph_debug.h> + +#include <linux/crc32c.h> +#include <linux/ctype.h> +#include <linux/highmem.h> +#include <linux/inet.h> +#include <linux/kthread.h> +#include <linux/net.h> +#include <linux/slab.h> +#include <linux/socket.h> +#include <linux/string.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/dns_resolver.h> +#include <net/tcp.h> + +#include <linux/ceph/libceph.h> +#include <linux/ceph/messenger.h> +#include <linux/ceph/decode.h> +#include <linux/ceph/pagelist.h> +#include <linux/export.h> + +/* + * 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 + +/* + * When skipping (ignoring) a block of input we read it into a "skip + * buffer," which is this many bytes in size. + */ +#define SKIP_BUF_SIZE 1024 + +static void queue_con(struct ceph_connection *con); +static void con_work(struct work_struct *); +static void ceph_fault(struct ceph_connection *con); + +/* + * Nicely render a sockaddr as a string. An array of formatted + * strings is used, to approximate reentrancy. + */ +#define ADDR_STR_COUNT_LOG 5 /* log2(# address strings in array) */ +#define ADDR_STR_COUNT (1 << ADDR_STR_COUNT_LOG) +#define ADDR_STR_COUNT_MASK (ADDR_STR_COUNT - 1) +#define MAX_ADDR_STR_LEN 64 /* 54 is enough */ + +static char addr_str[ADDR_STR_COUNT][MAX_ADDR_STR_LEN]; +static atomic_t addr_str_seq = ATOMIC_INIT(0); + +static struct page *zero_page; /* used in certain error cases */ + +const char *ceph_pr_addr(const struct sockaddr_storage *ss) +{ + int i; + char *s; + struct sockaddr_in *in4 = (struct sockaddr_in *) ss; + struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) ss; + + i = atomic_inc_return(&addr_str_seq) & ADDR_STR_COUNT_MASK; + s = addr_str[i]; + + switch (ss->ss_family) { + case AF_INET: + snprintf(s, MAX_ADDR_STR_LEN, "%pI4:%hu", &in4->sin_addr, + ntohs(in4->sin_port)); + break; + + case AF_INET6: + snprintf(s, MAX_ADDR_STR_LEN, "[%pI6c]:%hu", &in6->sin6_addr, + ntohs(in6->sin6_port)); + break; + + default: + snprintf(s, MAX_ADDR_STR_LEN, "(unknown sockaddr family %hu)", + ss->ss_family); + } + + return s; +} +EXPORT_SYMBOL(ceph_pr_addr); + +static void encode_my_addr(struct ceph_messenger *msgr) +{ + memcpy(&msgr->my_enc_addr, &msgr->inst.addr, sizeof(msgr->my_enc_addr)); + ceph_encode_addr(&msgr->my_enc_addr); +} + +/* + * work queue for all reading and writing to/from the socket. + */ +static struct workqueue_struct *ceph_msgr_wq; + +void _ceph_msgr_exit(void) +{ + if (ceph_msgr_wq) { + destroy_workqueue(ceph_msgr_wq); + ceph_msgr_wq = NULL; + } + + BUG_ON(zero_page == NULL); + kunmap(zero_page); + page_cache_release(zero_page); + zero_page = NULL; +} + +int ceph_msgr_init(void) +{ + BUG_ON(zero_page != NULL); + zero_page = ZERO_PAGE(0); + page_cache_get(zero_page); + + ceph_msgr_wq = alloc_workqueue("ceph-msgr", WQ_NON_REENTRANT, 0); + if (ceph_msgr_wq) + return 0; + + pr_err("msgr_init failed to create workqueue\n"); + _ceph_msgr_exit(); + + return -ENOMEM; +} +EXPORT_SYMBOL(ceph_msgr_init); + +void ceph_msgr_exit(void) +{ + BUG_ON(ceph_msgr_wq == NULL); + + _ceph_msgr_exit(); +} +EXPORT_SYMBOL(ceph_msgr_exit); + +void ceph_msgr_flush(void) +{ + flush_workqueue(ceph_msgr_wq); +} +EXPORT_SYMBOL(ceph_msgr_flush); + + +/* + * 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 = 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 = sk->sk_user_data; + + /* only queue to workqueue if there is data we want to write, + * and there is sufficient space in the socket buffer to accept + * more data. clear SOCK_NOSPACE so that ceph_write_space() + * doesn't get called again until try_write() fills the socket + * buffer. See net/ipv4/tcp_input.c:tcp_check_space() + * and net/core/stream.c:sk_stream_write_space(). + */ + if (test_bit(WRITE_PENDING, &con->state)) { + if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) { + dout("ceph_write_space %p queueing write work\n", con); + clear_bit(SOCK_NOSPACE, &sk->sk_socket->flags); + queue_con(con); + } + } else { + dout("ceph_write_space %p nothing to write\n", con); + } +} + +/* socket's state has changed */ +static void ceph_state_change(struct sock *sk) +{ + struct ceph_connection *con = 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; + default: /* Everything else is uninteresting */ + break; + } +} + +/* + * set up socket callbacks + */ +static void set_sock_callbacks(struct socket *sock, + struct ceph_connection *con) +{ + struct sock *sk = sock->sk; + sk->sk_user_data = con; + sk->sk_data_ready = ceph_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 int ceph_tcp_connect(struct ceph_connection *con) +{ + struct sockaddr_storage *paddr = &con->peer_addr.in_addr; + struct socket *sock; + int ret; + + BUG_ON(con->sock); + ret = sock_create_kern(con->peer_addr.in_addr.ss_family, SOCK_STREAM, + IPPROTO_TCP, &sock); + if (ret) + return ret; + sock->sk->sk_allocation = GFP_NOFS; + +#ifdef CONFIG_LOCKDEP + lockdep_set_class(&sock->sk->sk_lock, &socket_class); +#endif + + set_sock_callbacks(sock, con); + + dout("connect %s\n", ceph_pr_addr(&con->peer_addr.in_addr)); + + ret = sock->ops->connect(sock, (struct sockaddr *)paddr, sizeof(*paddr), + O_NONBLOCK); + if (ret == -EINPROGRESS) { + dout("connect %s EINPROGRESS sk_state = %u\n", + ceph_pr_addr(&con->peer_addr.in_addr), + sock->sk->sk_state); + } else if (ret < 0) { + pr_err("connect %s error %d\n", + ceph_pr_addr(&con->peer_addr.in_addr), ret); + sock_release(sock); + con->error_msg = "connect error"; + + return ret; + } + con->sock = sock; + + return 0; +} + +static int ceph_tcp_recvmsg(struct socket *sock, void *buf, size_t len) +{ + struct kvec iov = {buf, len}; + struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL }; + int r; + + r = kernel_recvmsg(sock, &msg, &iov, 1, len, msg.msg_flags); + if (r == -EAGAIN) + r = 0; + return r; +} + +/* + * write something. @more is true if caller will be sending more data + * shortly. + */ +static int ceph_tcp_sendmsg(struct socket *sock, struct kvec *iov, + size_t kvlen, size_t len, int more) +{ + struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL }; + int r; + + if (more) + msg.msg_flags |= MSG_MORE; + else + msg.msg_flags |= MSG_EOR; /* superfluous, but what the hell */ + + r = kernel_sendmsg(sock, &msg, iov, kvlen, len); + if (r == -EAGAIN) + r = 0; + return r; +} + +static int ceph_tcp_sendpage(struct socket *sock, struct page *page, + int offset, size_t size, int more) +{ + int flags = MSG_DONTWAIT | MSG_NOSIGNAL | (more ? MSG_MORE : MSG_EOR); + int ret; + + ret = kernel_sendpage(sock, page, offset, size, flags); + if (ret == -EAGAIN) + ret = 0; + + return ret; +} + + +/* + * 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, + ceph_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); + con->peer_global_seq = 0; + cancel_delayed_work(&con->work); + mutex_unlock(&con->mutex); + queue_con(con); +} +EXPORT_SYMBOL(ceph_con_close); + +/* + * 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, ceph_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); +} +EXPORT_SYMBOL(ceph_con_open); + +/* + * return true if this connection ever successfully opened + */ +bool ceph_con_opened(struct ceph_connection *con) +{ + return con->connect_seq > 0; +} + +/* + * generic get/put + */ +struct ceph_connection *ceph_con_get(struct ceph_connection *con) +{ + int nref = __atomic_add_unless(&con->nref, 1, 0); + + dout("con_get %p nref = %d -> %d\n", con, nref, nref + 1); + + return nref ? con : NULL; +} + +void ceph_con_put(struct ceph_connection *con) +{ + int nref = atomic_dec_return(&con->nref); + + BUG_ON(nref < 0); + if (nref == 0) { + BUG_ON(con->sock); + kfree(con); + } + dout("con_put %p nref = %d -> %d\n", con, nref + 1, nref); +} + +/* + * 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); +} +EXPORT_SYMBOL(ceph_con_init); + + +/* + * We maintain a global counter to order connection attempts. Get + * a unique seq greater than @gt. + */ +static u32 get_global_seq(struct ceph_messenger *msgr, u32 gt) +{ + u32 ret; + + spin_lock(&msgr->global_seq_lock); + if (msgr->global_seq < gt) + msgr->global_seq = gt; + ret = ++msgr->global_seq; + spin_unlock(&msgr->global_seq_lock); + return ret; +} + +static void ceph_con_out_kvec_reset(struct ceph_connection *con) +{ + con->out_kvec_left = 0; + con->out_kvec_bytes = 0; + con->out_kvec_cur = &con->out_kvec[0]; +} + +static void ceph_con_out_kvec_add(struct ceph_connection *con, + size_t size, void *data) +{ + int index; + + index = con->out_kvec_left; + BUG_ON(index >= ARRAY_SIZE(con->out_kvec)); + + con->out_kvec[index].iov_len = size; + con->out_kvec[index].iov_base = data; + con->out_kvec_left++; + con->out_kvec_bytes += size; +} + +/* + * Prepare footer for currently outgoing message, and finish things + * off. Assumes out_kvec* are already valid.. we just add on to the end. + */ +static void prepare_write_message_footer(struct ceph_connection *con) +{ + struct ceph_msg *m = con->out_msg; + int v = con->out_kvec_left; + + 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; + u32 crc; + + ceph_con_out_kvec_reset(con); + con->out_kvec_is_msg = true; + con->out_msg_done = false; + + /* Sneak an ack in there first? If we can get it into the same + * TCP packet that's a good thing. */ + if (con->in_seq > con->in_seq_acked) { + con->in_seq_acked = con->in_seq; + ceph_con_out_kvec_add(con, sizeof (tag_ack), &tag_ack); + con->out_temp_ack = cpu_to_le64(con->in_seq_acked); + ceph_con_out_kvec_add(con, sizeof (con->out_temp_ack), + &con->out_temp_ack); + } + + m = list_first_entry(&con->out_queue, struct ceph_msg, list_head); + con->out_msg = m; + + /* put message on sent list */ + ceph_msg_get(m); + list_move_tail(&m->list_head, &con->out_sent); + + /* + * only assign outgoing seq # if we haven't sent this message + * yet. if it is requeued, resend with it's original seq. + */ + if (m->needs_out_seq) { + m->hdr.seq = cpu_to_le64(++con->out_seq); + m->needs_out_seq = false; + } + + 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 */ + ceph_con_out_kvec_add(con, sizeof (tag_msg), &tag_msg); + ceph_con_out_kvec_add(con, sizeof (m->hdr), &m->hdr); + ceph_con_out_kvec_add(con, m->front.iov_len, m->front.iov_base); + + if (m->middle) + ceph_con_out_kvec_add(con, m->middle->vec.iov_len, + m->middle->vec.iov_base); + + /* fill in crc (except data pages), footer */ + crc = crc32c(0, &m->hdr, offsetof(struct ceph_msg_header, crc)); + con->out_msg->hdr.crc = cpu_to_le32(crc); + con->out_msg->footer.flags = CEPH_MSG_FOOTER_COMPLETE; + + crc = crc32c(0, m->front.iov_base, m->front.iov_len); + con->out_msg->footer.front_crc = cpu_to_le32(crc); + if (m->middle) { + crc = crc32c(0, m->middle->vec.iov_base, + m->middle->vec.iov_len); + con->out_msg->footer.middle_crc = cpu_to_le32(crc); + } else + con->out_msg->footer.middle_crc = 0; + 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; + if (m->pages) + con->out_msg_pos.page_pos = m->page_alignment; + else + con->out_msg_pos.page_pos = 0; + con->out_msg_pos.data_pos = 0; + con->out_msg_pos.did_page_crc = false; + con->out_more = 1; /* data + footer will follow */ + } else { + /* no, queue up footer too and be done */ + prepare_write_message_footer(con); + } + + 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; + + ceph_con_out_kvec_reset(con); + + ceph_con_out_kvec_add(con, sizeof (tag_ack), &tag_ack); + + con->out_temp_ack = cpu_to_le64(con->in_seq_acked); + ceph_con_out_kvec_add(con, sizeof (con->out_temp_ack), + &con->out_temp_ack); + + 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); + ceph_con_out_kvec_reset(con); + ceph_con_out_kvec_add(con, sizeof (tag_keepalive), &tag_keepalive); + set_bit(WRITE_PENDING, &con->state); +} + +/* + * Connection negotiation. + */ + +static int 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); + + if (test_bit(CLOSED, &con->state) || + test_bit(OPENING, &con->state)) + return -EAGAIN; + + con->out_connect.authorizer_protocol = cpu_to_le32(auth_protocol); + con->out_connect.authorizer_len = cpu_to_le32(auth_len); + + if (auth_len) + ceph_con_out_kvec_add(con, auth_len, auth_buf); + + return 0; +} + +/* + * We connected to a peer and are saying hello. + */ +static void prepare_write_banner(struct ceph_messenger *msgr, + struct ceph_connection *con) +{ + ceph_con_out_kvec_reset(con); + ceph_con_out_kvec_add(con, strlen(CEPH_BANNER), CEPH_BANNER); + ceph_con_out_kvec_add(con, sizeof (msgr->my_enc_addr), + &msgr->my_enc_addr); + + con->out_more = 0; + set_bit(WRITE_PENDING, &con->state); +} + +static int prepare_write_connect(struct ceph_messenger *msgr, + struct ceph_connection *con, + int include_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 = cpu_to_le64(msgr->supported_features); + con->out_connect.host_type = cpu_to_le32(CEPH_ENTITY_TYPE_CLIENT); + con->out_connect.connect_seq = cpu_to_le32(con->connect_seq); + con->out_connect.global_seq = cpu_to_le32(global_seq); + con->out_connect.protocol_version = cpu_to_le32(proto); + con->out_connect.flags = 0; + + if (include_banner) + prepare_write_banner(msgr, con); + else + ceph_con_out_kvec_reset(con); + ceph_con_out_kvec_add(con, sizeof (con->out_connect), &con->out_connect); + + con->out_more = 0; + set_bit(WRITE_PENDING, &con->state); + + return 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 */ + + /* account for full iov entries consumed */ + while (ret >= con->out_kvec_cur->iov_len) { + BUG_ON(!con->out_kvec_left); + ret -= con->out_kvec_cur->iov_len; + con->out_kvec_cur++; + con->out_kvec_left--; + } + /* and for a partially-consumed entry */ + if (ret) { + con->out_kvec_cur->iov_len -= ret; + con->out_kvec_cur->iov_base += ret; + } + } + con->out_kvec_left = 0; + con->out_kvec_is_msg = false; + ret = 1; +out: + dout("write_partial_kvec %p %d left in %d kvecs ret = %d\n", con, + con->out_kvec_bytes, con->out_kvec_left, ret); + return ret; /* done! */ +} + +#ifdef CONFIG_BLOCK +static void init_bio_iter(struct bio *bio, struct bio **iter, int *seg) +{ + if (!bio) { + *iter = NULL; + *seg = 0; + return; + } + *iter = bio; + *seg = bio->bi_idx; +} + +static void iter_bio_next(struct bio **bio_iter, int *seg) +{ + if (*bio_iter == NULL) + return; + + BUG_ON(*seg >= (*bio_iter)->bi_vcnt); + + (*seg)++; + if (*seg == (*bio_iter)->bi_vcnt) + init_bio_iter((*bio_iter)->bi_next, bio_iter, seg); +} +#endif + +/* + * 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; + bool do_datacrc = !con->msgr->nocrc; + int ret; + int total_max_write; + int in_trail = 0; + size_t trail_len = (msg->trail ? msg->trail->length : 0); + + 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); + +#ifdef CONFIG_BLOCK + if (msg->bio && !msg->bio_iter) + init_bio_iter(msg->bio, &msg->bio_iter, &msg->bio_seg); +#endif + + while (data_len > con->out_msg_pos.data_pos) { + struct page *page = NULL; + int max_write = PAGE_SIZE; + int bio_offset = 0; + + total_max_write = data_len - trail_len - + con->out_msg_pos.data_pos; + + /* + * 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. + */ + + /* have we reached the trail part of the data? */ + if (con->out_msg_pos.data_pos >= data_len - trail_len) { + in_trail = 1; + + total_max_write = data_len - con->out_msg_pos.data_pos; + + page = list_first_entry(&msg->trail->head, + struct page, lru); + max_write = PAGE_SIZE; + } else if (msg->pages) { + page = msg->pages[con->out_msg_pos.page]; + } else if (msg->pagelist) { + page = list_first_entry(&msg->pagelist->head, + struct page, lru); +#ifdef CONFIG_BLOCK + } else if (msg->bio) { + struct bio_vec *bv; + + bv = bio_iovec_idx(msg->bio_iter, msg->bio_seg); + page = bv->bv_page; + bio_offset = bv->bv_offset; + max_write = bv->bv_len; +#endif + } else { + page = zero_page; + } + len = min_t(int, max_write - con->out_msg_pos.page_pos, + total_max_write); + + if (do_datacrc && !con->out_msg_pos.did_page_crc) { + void *base; + u32 crc; + u32 tmpcrc = le32_to_cpu(con->out_msg->footer.data_crc); + char *kaddr; + + kaddr = kmap(page); + BUG_ON(kaddr == NULL); + base = kaddr + con->out_msg_pos.page_pos + bio_offset; + crc = crc32c(tmpcrc, base, len); + con->out_msg->footer.data_crc = cpu_to_le32(crc); + con->out_msg_pos.did_page_crc = true; + } + ret = ceph_tcp_sendpage(con->sock, page, + con->out_msg_pos.page_pos + bio_offset, + len, 1); + + if (do_datacrc) + 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 = false; + if (in_trail) + list_move_tail(&page->lru, + &msg->trail->head); + else if (msg->pagelist) + list_move_tail(&page->lru, + &msg->pagelist->head); +#ifdef CONFIG_BLOCK + else if (msg->bio) + iter_bio_next(&msg->bio_iter, &msg->bio_seg); +#endif + } + } + + dout("write_partial_msg_pages %p msg %p done\n", con, msg); + + /* prepare and queue up footer, too */ + if (!do_datacrc) + con->out_msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC; + ceph_con_out_kvec_reset(con); + prepare_write_message_footer(con); + ret = 1; +out: + return ret; +} + +/* + * write some zeros + */ +static int write_partial_skip(struct ceph_connection *con) +{ + int ret; + + while (con->out_skip > 0) { + size_t size = min(con->out_skip, (int) PAGE_CACHE_SIZE); + + ret = ceph_tcp_sendpage(con->sock, zero_page, 0, size, 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", + ceph_pr_addr(&con->peer_addr.in_addr)); + con->error_msg = "protocol error, bad banner"; + return -1; + } + return 0; +} + +static bool addr_is_blank(struct sockaddr_storage *ss) +{ + switch (ss->ss_family) { + case AF_INET: + return ((struct sockaddr_in *)ss)->sin_addr.s_addr == 0; + case AF_INET6: + return + ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[0] == 0 && + ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[1] == 0 && + ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[2] == 0 && + ((struct sockaddr_in6 *)ss)->sin6_addr.s6_addr32[3] == 0; + } + return false; +} + +static int addr_port(struct sockaddr_storage *ss) +{ + switch (ss->ss_family) { + case AF_INET: + return ntohs(((struct sockaddr_in *)ss)->sin_port); + case AF_INET6: + return ntohs(((struct sockaddr_in6 *)ss)->sin6_port); + } + return 0; +} + +static void addr_set_port(struct sockaddr_storage *ss, int p) +{ + switch (ss->ss_family) { + case AF_INET: + ((struct sockaddr_in *)ss)->sin_port = htons(p); + break; + case AF_INET6: + ((struct sockaddr_in6 *)ss)->sin6_port = htons(p); + break; + } +} + +/* + * Unlike other *_pton function semantics, zero indicates success. + */ +static int ceph_pton(const char *str, size_t len, struct sockaddr_storage *ss, + char delim, const char **ipend) +{ + struct sockaddr_in *in4 = (struct sockaddr_in *) ss; + struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) ss; + + memset(ss, 0, sizeof(*ss)); + + if (in4_pton(str, len, (u8 *)&in4->sin_addr.s_addr, delim, ipend)) { + ss->ss_family = AF_INET; + return 0; + } + + if (in6_pton(str, len, (u8 *)&in6->sin6_addr.s6_addr, delim, ipend)) { + ss->ss_family = AF_INET6; + return 0; + } + + return -EINVAL; +} + +/* + * Extract hostname string and resolve using kernel DNS facility. + */ +#ifdef CONFIG_CEPH_LIB_USE_DNS_RESOLVER +static int ceph_dns_resolve_name(const char *name, size_t namelen, + struct sockaddr_storage *ss, char delim, const char **ipend) +{ + const char *end, *delim_p; + char *colon_p, *ip_addr = NULL; + int ip_len, ret; + + /* + * The end of the hostname occurs immediately preceding the delimiter or + * the port marker (':') where the delimiter takes precedence. + */ + delim_p = memchr(name, delim, namelen); + colon_p = memchr(name, ':', namelen); + + if (delim_p && colon_p) + end = delim_p < colon_p ? delim_p : colon_p; + else if (!delim_p && colon_p) + end = colon_p; + else { + end = delim_p; + if (!end) /* case: hostname:/ */ + end = name + namelen; + } + + if (end <= name) + return -EINVAL; + + /* do dns_resolve upcall */ + ip_len = dns_query(NULL, name, end - name, NULL, &ip_addr, NULL); + if (ip_len > 0) + ret = ceph_pton(ip_addr, ip_len, ss, -1, NULL); + else + ret = -ESRCH; + + kfree(ip_addr); + + *ipend = end; + + pr_info("resolve '%.*s' (ret=%d): %s\n", (int)(end - name), name, + ret, ret ? "failed" : ceph_pr_addr(ss)); + + return ret; +} +#else +static inline int ceph_dns_resolve_name(const char *name, size_t namelen, + struct sockaddr_storage *ss, char delim, const char **ipend) +{ + return -EINVAL; +} +#endif + +/* + * Parse a server name (IP or hostname). If a valid IP address is not found + * then try to extract a hostname to resolve using userspace DNS upcall. + */ +static int ceph_parse_server_name(const char *name, size_t namelen, + struct sockaddr_storage *ss, char delim, const char **ipend) +{ + int ret; + + ret = ceph_pton(name, namelen, ss, delim, ipend); + if (ret) + ret = ceph_dns_resolve_name(name, namelen, ss, delim, ipend); + + return ret; +} + +/* + * Parse an ip[:port] list into an addr array. Use the default + * monitor port if a port isn't specified. + */ +int ceph_parse_ips(const char *c, const char *end, + struct ceph_entity_addr *addr, + int max_count, int *count) +{ + int i, ret = -EINVAL; + const char *p = c; + + dout("parse_ips on '%.*s'\n", (int)(end-c), c); + for (i = 0; i < max_count; i++) { + const char *ipend; + struct sockaddr_storage *ss = &addr[i].in_addr; + int port; + char delim = ','; + + if (*p == '[') { + delim = ']'; + p++; + } + + ret = ceph_parse_server_name(p, end - p, ss, delim, &ipend); + if (ret) + goto bad; + ret = -EINVAL; + + p = ipend; + + if (delim == ']') { + if (*p != ']') { + dout("missing matching ']'\n"); + goto bad; + } + p++; + } + + /* port? */ + if (p < end && *p == ':') { + port = 0; + p++; + while (p < end && *p >= '0' && *p <= '9') { + port = (port * 10) + (*p - '0'); + p++; + } + if (port > 65535 || port == 0) + goto bad; + } else { + port = CEPH_MON_PORT; + } + + addr_set_port(ss, port); + + dout("parse_ips got %s\n", ceph_pr_addr(ss)); + + if (p == end) + break; + if (*p != ',') + goto bad; + p++; + } + + if (p != end) + goto bad; + + if (count) + *count = i + 1; + return 0; + +bad: + pr_err("parse_ips bad ip '%.*s'\n", (int)(end - c), c); + return ret; +} +EXPORT_SYMBOL(ceph_parse_ips); + +static int process_banner(struct ceph_connection *con) +{ + dout("process_banner on %p\n", con); + + if (verify_hello(con) < 0) + return -1; + + ceph_decode_addr(&con->actual_peer_addr); + ceph_decode_addr(&con->peer_addr_for_me); + + /* + * Make sure the other end is who we wanted. note that the other + * end may not yet know their ip address, so if it's 0.0.0.0, give + * them the benefit of the doubt. + */ + if (memcmp(&con->peer_addr, &con->actual_peer_addr, + sizeof(con->peer_addr)) != 0 && + !(addr_is_blank(&con->actual_peer_addr.in_addr) && + con->actual_peer_addr.nonce == con->peer_addr.nonce)) { + pr_warning("wrong peer, want %s/%d, got %s/%d\n", + ceph_pr_addr(&con->peer_addr.in_addr), + (int)le32_to_cpu(con->peer_addr.nonce), + ceph_pr_addr(&con->actual_peer_addr.in_addr), + (int)le32_to_cpu(con->actual_peer_addr.nonce)); + con->error_msg = "wrong peer at address"; + return -1; + } + + /* + * did we learn our address? + */ + if (addr_is_blank(&con->msgr->inst.addr.in_addr)) { + int port = addr_port(&con->msgr->inst.addr.in_addr); + + memcpy(&con->msgr->inst.addr.in_addr, + &con->peer_addr_for_me.in_addr, + sizeof(con->peer_addr_for_me.in_addr)); + addr_set_port(&con->msgr->inst.addr.in_addr, port); + encode_my_addr(con->msgr); + dout("process_banner learned my addr is %s\n", + ceph_pr_addr(&con->msgr->inst.addr.in_addr)); + } + + 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 = con->msgr->supported_features; + u64 req_feat = con->msgr->required_features; + u64 server_feat = le64_to_cpu(con->in_reply.features); + int ret; + + dout("process_connect on %p tag %d\n", con, (int)con->in_tag); + + switch (con->in_reply.tag) { + case CEPH_MSGR_TAG_FEATURES: + pr_err("%s%lld %s feature set mismatch," + " my %llx < server's %llx, missing %llx\n", + ENTITY_NAME(con->peer_name), + ceph_pr_addr(&con->peer_addr.in_addr), + sup_feat, server_feat, server_feat & ~sup_feat); + con->error_msg = "missing required protocol features"; + 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), + ceph_pr_addr(&con->peer_addr.in_addr), + le32_to_cpu(con->out_connect.protocol_version), + le32_to_cpu(con->in_reply.protocol_version)); + con->error_msg = "protocol version mismatch"; + 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"; + return -1; + } + con->auth_retry = 1; + ret = prepare_write_connect(con->msgr, con, 0); + if (ret < 0) + return ret; + prepare_read_connect(con); + break; + + case CEPH_MSGR_TAG_RESETSESSION: + /* + * If we connected with a large connect_seq but the peer + * has no record of a session with us (no connection, or + * connect_seq == 0), they will send RESETSESION to indicate + * that they must have reset their session, and may have + * dropped messages. + */ + dout("process_connect got RESET peer seq %u\n", + le32_to_cpu(con->in_connect.connect_seq)); + pr_err("%s%lld %s connection reset\n", + ENTITY_NAME(con->peer_name), + ceph_pr_addr(&con->peer_addr.in_addr)); + reset_connection(con); + 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); + if (test_bit(CLOSED, &con->state) || + test_bit(OPENING, &con->state)) + return -EAGAIN; + break; + + case CEPH_MSGR_TAG_RETRY_SESSION: + /* + * If we sent a smaller connect_seq than the peer has, try + * again with a larger value. + */ + dout("process_connect got RETRY 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), + ceph_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++; + con->peer_features = server_feat; + dout("process_connect got READY gseq %d cseq %d (%d)\n", + con->peer_global_seq, + le32_to_cpu(con->in_reply.connect_seq), + con->connect_seq); + WARN_ON(con->connect_seq != + le32_to_cpu(con->in_reply.connect_seq)); + + if (con->in_reply.flags & CEPH_MSG_CONNECT_LOSSY) + 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 got WAIT as client\n"); + con->error_msg = "protocol error, got WAIT as client"; + return -1; + + 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); + m->ack_stamp = jiffies; + ceph_msg_remove(m); + } + prepare_read_tag(con); +} + + + + +static int read_partial_message_section(struct ceph_connection *con, + struct kvec *section, + unsigned int sec_len, u32 *crc) +{ + int ret, left; + + BUG_ON(!section); + + while (section->iov_len < sec_len) { + BUG_ON(section->iov_base == NULL); + left = sec_len - section->iov_len; + ret = ceph_tcp_recvmsg(con->sock, (char *)section->iov_base + + section->iov_len, left); + if (ret <= 0) + return ret; + section->iov_len += ret; + } + if (section->iov_len == sec_len) + *crc = crc32c(0, section->iov_base, section->iov_len); + + return 1; +} + +static struct ceph_msg *ceph_alloc_msg(struct ceph_connection *con, + struct ceph_msg_header *hdr, + int *skip); + + +static int read_partial_message_pages(struct ceph_connection *con, + struct page **pages, + unsigned data_len, bool do_datacrc) +{ + void *p; + int ret; + int left; + + left = min((int)(data_len - con->in_msg_pos.data_pos), + (int)(PAGE_SIZE - con->in_msg_pos.page_pos)); + /* (page) data */ + BUG_ON(pages == NULL); + p = kmap(pages[con->in_msg_pos.page]); + ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos, + left); + if (ret > 0 && do_datacrc) + con->in_data_crc = + crc32c(con->in_data_crc, + p + con->in_msg_pos.page_pos, ret); + kunmap(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++; + } + + return ret; +} + +#ifdef CONFIG_BLOCK +static int read_partial_message_bio(struct ceph_connection *con, + struct bio **bio_iter, int *bio_seg, + unsigned data_len, bool do_datacrc) +{ + struct bio_vec *bv = bio_iovec_idx(*bio_iter, *bio_seg); + void *p; + int ret, left; + + if (IS_ERR(bv)) + return PTR_ERR(bv); + + left = min((int)(data_len - con->in_msg_pos.data_pos), + (int)(bv->bv_len - con->in_msg_pos.page_pos)); + + p = kmap(bv->bv_page) + bv->bv_offset; + + ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos, + left); + if (ret > 0 && do_datacrc) + con->in_data_crc = + crc32c(con->in_data_crc, + p + con->in_msg_pos.page_pos, ret); + kunmap(bv->bv_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 == bv->bv_len) { + con->in_msg_pos.page_pos = 0; + iter_bio_next(bio_iter, bio_seg); + } + + return ret; +} +#endif + +/* + * read (part of) a message. + */ +static int read_partial_message(struct ceph_connection *con) +{ + struct ceph_msg *m = con->in_msg; + int ret; + int to, left; + unsigned front_len, middle_len, data_len; + bool do_datacrc = !con->msgr->nocrc; + int skip; + u64 seq; + u32 crc; + + 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; + } + + crc = crc32c(0, &con->in_hdr, offsetof(struct ceph_msg_header, crc)); + if (cpu_to_le32(crc) != con->in_hdr.crc) { + pr_err("read_partial_message bad hdr " + " crc %u != expected %u\n", + crc, con->in_hdr.crc); + return -EBADMSG; + } + + front_len = le32_to_cpu(con->in_hdr.front_len); + if (front_len > CEPH_MSG_MAX_FRONT_LEN) + return -EIO; + middle_len = le32_to_cpu(con->in_hdr.middle_len); + if (middle_len > CEPH_MSG_MAX_DATA_LEN) + return -EIO; + data_len = le32_to_cpu(con->in_hdr.data_len); + if (data_len > CEPH_MSG_MAX_DATA_LEN) + return -EIO; + + /* verify seq# */ + seq = le64_to_cpu(con->in_hdr.seq); + if ((s64)seq - (s64)con->in_seq < 1) { + pr_info("skipping %s%lld %s seq %lld expected %lld\n", + ENTITY_NAME(con->peer_name), + ceph_pr_addr(&con->peer_addr.in_addr), + seq, con->in_seq + 1); + con->in_base_pos = -front_len - middle_len - data_len - + sizeof(m->footer); + con->in_tag = CEPH_MSGR_TAG_READY; + return 0; + } else if ((s64)seq - (s64)con->in_seq > 1) { + pr_err("read_partial_message bad seq %lld expected %lld\n", + seq, con->in_seq + 1); + con->error_msg = "bad message sequence # for incoming message"; + return -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); + skip = 0; + con->in_msg = ceph_alloc_msg(con, &con->in_hdr, &skip); + if (skip) { + /* skip this message */ + dout("alloc_msg said skip message\n"); + BUG_ON(con->in_msg); + 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 (!con->in_msg) { + con->error_msg = + "error allocating memory for incoming message"; + return -ENOMEM; + } + 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; + if (m->pages) + con->in_msg_pos.page_pos = m->page_alignment; + else + con->in_msg_pos.page_pos = 0; + 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; + } +#ifdef CONFIG_BLOCK + if (m->bio && !m->bio_iter) + init_bio_iter(m->bio, &m->bio_iter, &m->bio_seg); +#endif + + /* (page) data */ + while (con->in_msg_pos.data_pos < data_len) { + if (m->pages) { + ret = read_partial_message_pages(con, m->pages, + data_len, do_datacrc); + if (ret <= 0) + return ret; +#ifdef CONFIG_BLOCK + } else if (m->bio) { + + ret = read_partial_message_bio(con, + &m->bio_iter, &m->bio_seg, + data_len, do_datacrc); + if (ret <= 0) + return ret; +#endif + } else { + BUG_ON(1); + } + } + + /* 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 (do_datacrc && + (m->footer.flags & CEPH_MSG_FOOTER_NOCRC) == 0 && + con->in_data_crc != le32_to_cpu(m->footer.data_crc)) { + pr_err("read_partial_message %p data crc %u != exp. %u\n", m, + con->in_data_crc, le32_to_cpu(m->footer.data_crc)); + return -EBADMSG; + } + + 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; + + con->in_seq++; + mutex_unlock(&con->mutex); + + dout("===== %p %llu from %s%lld %d=%s len %d+%d (%u %u %u) =====\n", + msg, le64_to_cpu(msg->hdr.seq), + ENTITY_NAME(msg->hdr.src), + le16_to_cpu(msg->hdr.type), + ceph_msg_type_name(le16_to_cpu(msg->hdr.type)), + le32_to_cpu(msg->hdr.front_len), + le32_to_cpu(msg->hdr.data_len), + con->in_front_crc, con->in_middle_crc, con->in_data_crc); + con->ops->dispatch(con, msg); + + mutex_lock(&con->mutex); + 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)); + +more: + dout("try_write out_kvec_bytes %d\n", con->out_kvec_bytes); + + /* open the socket first? */ + if (con->sock == NULL) { + 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); + ret = ceph_tcp_connect(con); + if (ret < 0) { + con->error_msg = "connect error"; + goto out; + } + } + +more_kvec: + /* kvec data queued? */ + if (con->out_skip) { + ret = write_partial_skip(con); + if (ret <= 0) + goto out; + } + if (con->out_kvec_left) { + ret = write_partial_kvec(con); + if (ret <= 0) + goto out; + } + + /* msg pages? */ + if (con->out_msg) { + if (con->out_msg_done) { + ceph_msg_put(con->out_msg); + con->out_msg = NULL; /* we're done with this one */ + goto do_next; + } + + ret = write_partial_msg_pages(con); + if (ret == 1) + goto more_kvec; /* we need to send the footer, too! */ + if (ret == 0) + goto out; + if (ret < 0) { + dout("try_write write_partial_msg_pages err %d\n", + ret); + goto out; + } + } + +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"); + ret = 0; +out: + dout("try_write done on %p ret %d\n", con, ret); + return ret; +} + + + +/* + * Read what we can from the socket. + */ +static int try_read(struct ceph_connection *con) +{ + int ret = -1; + + if (!con->sock) + return 0; + + if (test_bit(STANDBY, &con->state)) + return 0; + + dout("try_read start on %p\n", con); + +more: + dout("try_read tag %d in_base_pos %d\n", (int)con->in_tag, + con->in_base_pos); + + /* + * process_connect and process_message drop and re-take + * con->mutex. make sure we handle a racing close or reopen. + */ + if (test_bit(CLOSED, &con->state) || + test_bit(OPENING, &con->state)) { + ret = -EAGAIN; + goto out; + } + + 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 out; + ret = process_banner(con); + if (ret < 0) + goto out; + } + ret = read_partial_connect(con); + if (ret <= 0) + goto out; + ret = process_connect(con); + if (ret < 0) + 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[SKIP_BUF_SIZE]; + int skip = min((int) sizeof (buf), -con->in_base_pos); + + dout("skipping %d / %d bytes\n", skip, -con->in_base_pos); + ret = ceph_tcp_recvmsg(con->sock, buf, skip); + if (ret <= 0) + goto out; + con->in_base_pos += ret; + if (con->in_base_pos) + goto more; + } + if (con->in_tag == CEPH_MSGR_TAG_READY) { + /* + * what's next? + */ + ret = ceph_tcp_recvmsg(con->sock, &con->in_tag, 1); + if (ret <= 0) + goto out; + dout("try_read got tag %d\n", (int)con->in_tag); + switch (con->in_tag) { + case CEPH_MSGR_TAG_MSG: + prepare_read_message(con); + break; + case CEPH_MSGR_TAG_ACK: + prepare_read_ack(con); + break; + case CEPH_MSGR_TAG_CLOSE: + set_bit(CLOSED, &con->state); /* fixme */ + goto out; + default: + goto bad_tag; + } + } + if (con->in_tag == CEPH_MSGR_TAG_MSG) { + ret = read_partial_message(con); + if (ret <= 0) { + switch (ret) { + case -EBADMSG: + con->error_msg = "bad crc"; + ret = -EIO; + break; + case -EIO: + con->error_msg = "io error"; + break; + } + goto out; + } + if (con->in_tag == CEPH_MSGR_TAG_READY) + goto more; + process_message(con); + goto more; + } + if (con->in_tag == CEPH_MSGR_TAG_ACK) { + ret = read_partial_ack(con); + if (ret <= 0) + goto out; + process_ack(con); + goto more; + } + +out: + dout("try_read done on %p ret %d\n", con, ret); + return ret; + +bad_tag: + pr_err("try_read bad con->in_tag = %d\n", (int)con->in_tag); + con->error_msg = "protocol error, garbage tag"; + ret = -1; + goto out; +} + + +/* + * Atomically queue work on a connection. Bump @con reference to + * avoid races with connection teardown. + */ +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; + } + + if (!queue_delayed_work(ceph_msgr_wq, &con->work, 0)) { + 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 ret; + + mutex_lock(&con->mutex); +restart: + if (test_and_clear_bit(BACKOFF, &con->state)) { + dout("con_work %p backing off\n", con); + if (queue_delayed_work(ceph_msgr_wq, &con->work, + round_jiffies_relative(con->delay))) { + dout("con_work %p backoff %lu\n", con, con->delay); + mutex_unlock(&con->mutex); + return; + } else { + con->ops->put(con); + dout("con_work %p FAILED to back off %lu\n", con, + con->delay); + } + } + + if (test_bit(STANDBY, &con->state)) { + dout("con_work %p STANDBY\n", con); + goto done; + } + 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)) + goto fault; + + ret = try_read(con); + if (ret == -EAGAIN) + goto restart; + if (ret < 0) + goto fault; + + ret = try_write(con); + if (ret == -EAGAIN) + goto restart; + if (ret < 0) + goto fault; + +done: + mutex_unlock(&con->mutex); +done_unlocked: + con->ops->put(con); + return; + +fault: + mutex_unlock(&con->mutex); + ceph_fault(con); /* error/fault path */ + goto done_unlocked; +} + + +/* + * 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), + ceph_pr_addr(&con->peer_addr.in_addr), con->error_msg); + dout("fault %p state %lu to peer %s\n", + con, con->state, ceph_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 queued or keepalive pending, place + * the connection in a STANDBY state */ + if (list_empty(&con->out_queue) && + !test_bit(KEEPALIVE_PENDING, &con->state)) { + dout("fault %p setting STANDBY clearing WRITE_PENDING\n", con); + clear_bit(WRITE_PENDING, &con->state); + 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; + con->ops->get(con); + if (queue_delayed_work(ceph_msgr_wq, &con->work, + round_jiffies_relative(con->delay))) { + dout("fault queued %p delay %lu\n", con, con->delay); + } else { + con->ops->put(con); + dout("fault failed to queue %p delay %lu, backoff\n", + con, con->delay); + /* + * In many cases we see a socket state change + * while con_work is running and end up + * queuing (non-delayed) work, such that we + * can't backoff with a delay. Set a flag so + * that when con_work restarts we schedule the + * delay then. + */ + set_bit(BACKOFF, &con->state); + } + } + +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, + u32 supported_features, + u32 required_features) +{ + struct ceph_messenger *msgr; + + msgr = kzalloc(sizeof(*msgr), GFP_KERNEL); + if (msgr == NULL) + return ERR_PTR(-ENOMEM); + + msgr->supported_features = supported_features; + msgr->required_features = required_features; + + spin_lock_init(&msgr->global_seq_lock); + + if (myaddr) + msgr->inst.addr = *myaddr; + + /* select a random nonce */ + msgr->inst.addr.type = 0; + get_random_bytes(&msgr->inst.addr.nonce, sizeof(msgr->inst.addr.nonce)); + encode_my_addr(msgr); + + dout("messenger_create %p\n", msgr); + return msgr; +} +EXPORT_SYMBOL(ceph_messenger_create); + +void ceph_messenger_destroy(struct ceph_messenger *msgr) +{ + dout("destroy %p\n", msgr); + kfree(msgr); + dout("destroyed messenger %p\n", msgr); +} +EXPORT_SYMBOL(ceph_messenger_destroy); + +static void clear_standby(struct ceph_connection *con) +{ + /* come back from STANDBY? */ + if (test_and_clear_bit(STANDBY, &con->state)) { + mutex_lock(&con->mutex); + dout("clear_standby %p and ++connect_seq\n", con); + con->connect_seq++; + WARN_ON(test_bit(WRITE_PENDING, &con->state)); + WARN_ON(test_bit(KEEPALIVE_PENDING, &con->state)); + mutex_unlock(&con->mutex); + } +} + +/* + * 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.name; + + BUG_ON(msg->front.iov_len != le32_to_cpu(msg->hdr.front_len)); + + msg->needs_out_seq = true; + + /* 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 */ + clear_standby(con); + if (test_and_set_bit(WRITE_PENDING, &con->state) == 0) + queue_con(con); +} +EXPORT_SYMBOL(ceph_con_send); + +/* + * 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 - was on queue\n", con, msg); + list_del_init(&msg->list_head); + ceph_msg_put(msg); + msg->hdr.seq = 0; + } + if (con->out_msg == msg) { + dout("con_revoke %p msg %p - was sending\n", con, msg); + con->out_msg = NULL; + if (con->out_kvec_is_msg) { + con->out_skip = con->out_kvec_bytes; + con->out_kvec_is_msg = false; + } + ceph_msg_put(msg); + msg->hdr.seq = 0; + } + 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) +{ + dout("con_keepalive %p\n", con); + clear_standby(con); + if (test_and_set_bit(KEEPALIVE_PENDING, &con->state) == 0 && + test_and_set_bit(WRITE_PENDING, &con->state) == 0) + queue_con(con); +} +EXPORT_SYMBOL(ceph_con_keepalive); + + +/* + * construct a new message with given type, size + * the new msg has a ref count of 1. + */ +struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags, + bool can_fail) +{ + struct ceph_msg *m; + + m = kmalloc(sizeof(*m), flags); + if (m == NULL) + goto out; + kref_init(&m->kref); + INIT_LIST_HEAD(&m->list_head); + + m->hdr.tid = 0; + m->hdr.type = cpu_to_le16(type); + m->hdr.priority = cpu_to_le16(CEPH_MSG_PRIO_DEFAULT); + m->hdr.version = 0; + m->hdr.front_len = cpu_to_le32(front_len); + m->hdr.middle_len = 0; + m->hdr.data_len = 0; + m->hdr.data_off = 0; + m->hdr.reserved = 0; + m->footer.front_crc = 0; + m->footer.middle_crc = 0; + m->footer.data_crc = 0; + m->footer.flags = 0; + m->front_max = front_len; + m->front_is_vmalloc = false; + m->more_to_follow = false; + m->ack_stamp = 0; + m->pool = NULL; + + /* middle */ + m->middle = NULL; + + /* data */ + m->nr_pages = 0; + m->page_alignment = 0; + m->pages = NULL; + m->pagelist = NULL; + m->bio = NULL; + m->bio_iter = NULL; + m->bio_seg = 0; + m->trail = NULL; + + /* front */ + if (front_len) { + if (front_len > PAGE_CACHE_SIZE) { + m->front.iov_base = __vmalloc(front_len, flags, + PAGE_KERNEL); + m->front_is_vmalloc = true; + } else { + m->front.iov_base = kmalloc(front_len, flags); + } + if (m->front.iov_base == NULL) { + dout("ceph_msg_new can't allocate %d bytes\n", + front_len); + goto out2; + } + } else { + m->front.iov_base = NULL; + } + m->front.iov_len = front_len; + + dout("ceph_msg_new %p front %d\n", m, front_len); + return m; + +out2: + ceph_msg_put(m); +out: + if (!can_fail) { + pr_err("msg_new can't create type %d front %d\n", type, + front_len); + WARN_ON(1); + } else { + dout("msg_new can't create type %d front %d\n", type, + front_len); + } + return NULL; +} +EXPORT_SYMBOL(ceph_msg_new); + +/* + * Allocate "middle" portion of a message, if it is needed and wasn't + * allocated by alloc_msg. This allows us to read a small fixed-size + * per-type header in the front and then gracefully fail (i.e., + * propagate the error to the caller based on info in the front) when + * the middle is too large. + */ +static int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg) +{ + int type = le16_to_cpu(msg->hdr.type); + int middle_len = le32_to_cpu(msg->hdr.middle_len); + + dout("alloc_middle %p type %d %s middle_len %d\n", msg, type, + ceph_msg_type_name(type), middle_len); + BUG_ON(!middle_len); + BUG_ON(msg->middle); + + msg->middle = ceph_buffer_new(middle_len, GFP_NOFS); + if (!msg->middle) + return -ENOMEM; + return 0; +} + +/* + * 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 (!msg || *skip) + return NULL; + } + if (!msg) { + *skip = 0; + msg = ceph_msg_new(type, front_len, GFP_NOFS, false); + if (!msg) { + pr_err("unable to allocate msg type %d len %d\n", + type, front_len); + return NULL; + } + msg->page_alignment = le16_to_cpu(hdr->data_off); + } + memcpy(&msg->hdr, &con->in_hdr, sizeof(con->in_hdr)); + + if (middle_len && !msg->middle) { + ret = ceph_alloc_middle(con, msg); + if (ret < 0) { + ceph_msg_put(msg); + return NULL; + } + } + + 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; + } + + m->trail = NULL; + + if (m->pool) + ceph_msgpool_put(m->pool, m); + else + ceph_msg_kfree(m); +} +EXPORT_SYMBOL(ceph_msg_last_put); + +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); +} +EXPORT_SYMBOL(ceph_msg_dump); |