- struct sock *sk = tcp_conn->sock->sk;
-
- /* assign new callbacks */
- write_lock_bh(&sk->sk_callback_lock);
- sk->sk_user_data = conn;
- tcp_conn->old_data_ready = sk->sk_data_ready;
- tcp_conn->old_state_change = sk->sk_state_change;
- tcp_conn->old_write_space = sk->sk_write_space;
- sk->sk_data_ready = iscsi_tcp_data_ready;
- sk->sk_state_change = iscsi_tcp_state_change;
- sk->sk_write_space = iscsi_write_space;
- write_unlock_bh(&sk->sk_callback_lock);
-}
-
-static void
-iscsi_conn_restore_callbacks(struct iscsi_tcp_conn *tcp_conn)
-{
- struct sock *sk = tcp_conn->sock->sk;
-
- /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
- write_lock_bh(&sk->sk_callback_lock);
- sk->sk_user_data = NULL;
- sk->sk_data_ready = tcp_conn->old_data_ready;
- sk->sk_state_change = tcp_conn->old_state_change;
- sk->sk_write_space = tcp_conn->old_write_space;
- sk->sk_no_check = 0;
- write_unlock_bh(&sk->sk_callback_lock);
-}
-
-/**
- * iscsi_send - generic send routine
- * @sk: kernel's socket
- * @buf: buffer to write from
- * @size: actual size to write
- * @flags: socket's flags
- */
-static inline int
-iscsi_send(struct iscsi_conn *conn, struct iscsi_buf *buf, int size, int flags)
-{
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- struct socket *sk = tcp_conn->sock;
- int offset = buf->sg.offset + buf->sent, res;
-
- /*
- * if we got use_sg=0 or are sending something we kmallocd
- * then we did not have to do kmap (kmap returns page_address)
- *
- * if we got use_sg > 0, but had to drop down, we do not
- * set clustering so this should only happen for that
- * slab case.
- */
- if (buf->use_sendmsg)
- res = sock_no_sendpage(sk, buf->sg.page, offset, size, flags);
- else
- res = tcp_conn->sendpage(sk, buf->sg.page, offset, size, flags);
-
- if (res >= 0) {
- conn->txdata_octets += res;
- buf->sent += res;
- return res;
- }
-
- tcp_conn->sendpage_failures_cnt++;
- if (res == -EAGAIN)
- res = -ENOBUFS;
- else
- iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
- return res;
-}
-
-/**
- * iscsi_sendhdr - send PDU Header via tcp_sendpage()
- * @conn: iscsi connection
- * @buf: buffer to write from
- * @datalen: lenght of data to be sent after the header
- *
- * Notes:
- * (Tx, Fast Path)
- **/
-static inline int
-iscsi_sendhdr(struct iscsi_conn *conn, struct iscsi_buf *buf, int datalen)
-{
- int flags = 0; /* MSG_DONTWAIT; */
- int res, size;
-
- size = buf->sg.length - buf->sent;
- BUG_ON(buf->sent + size > buf->sg.length);
- if (buf->sent + size != buf->sg.length || datalen)
- flags |= MSG_MORE;
-
- res = iscsi_send(conn, buf, size, flags);
- debug_tcp("sendhdr %d bytes, sent %d res %d\n", size, buf->sent, res);
- if (res >= 0) {
- if (size != res)
- return -EAGAIN;
- return 0;
- }
-
- return res;
-}
-
-/**
- * iscsi_sendpage - send one page of iSCSI Data-Out.
- * @conn: iscsi connection
- * @buf: buffer to write from
- * @count: remaining data
- * @sent: number of bytes sent
- *
- * Notes:
- * (Tx, Fast Path)
- **/
-static inline int
-iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
- int *count, int *sent)
-{
- int flags = 0; /* MSG_DONTWAIT; */
- int res, size;
-
- size = buf->sg.length - buf->sent;
- BUG_ON(buf->sent + size > buf->sg.length);
- if (size > *count)
- size = *count;
- if (buf->sent + size != buf->sg.length || *count != size)
- flags |= MSG_MORE;
-
- res = iscsi_send(conn, buf, size, flags);
- debug_tcp("sendpage: %d bytes, sent %d left %d sent %d res %d\n",
- size, buf->sent, *count, *sent, res);
- if (res >= 0) {
- *count -= res;
- *sent += res;
- if (size != res)
- return -EAGAIN;
- return 0;
- }
-
- return res;
-}
-
-static inline void
-iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
- struct iscsi_cmd_task *ctask)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-
- crypto_hash_init(&tcp_conn->data_tx_hash);
- tcp_ctask->digest_count = 4;
-}
-
-static int
-iscsi_digest_final_send(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
- struct iscsi_buf *buf, uint32_t *digest, int final)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- int rc = 0;
- int sent = 0;
-
- if (final)
- crypto_hash_final(&tcp_conn->data_tx_hash, (u8 *)digest);
-
- iscsi_buf_init_iov(buf, (char*)digest, 4);
- rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
- if (rc) {
- tcp_ctask->datadigest = *digest;
- tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
- } else
- tcp_ctask->digest_count = 4;
- return rc;
-}
-
-/**
- * iscsi_solicit_data_cont - initialize next Data-Out
- * @conn: iscsi connection
- * @ctask: scsi command task
- * @r2t: R2T info
- * @left: bytes left to transfer
- *
- * Notes:
- * Initialize next Data-Out within this R2T sequence and continue
- * to process next Scatter-Gather element(if any) of this SCSI command.
- *
- * Called under connection lock.
- **/
-static void
-iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
- struct iscsi_r2t_info *r2t, int left)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct iscsi_data *hdr;
- struct scsi_cmnd *sc = ctask->sc;
- int new_offset;
-
- hdr = &r2t->dtask.hdr;
- memset(hdr, 0, sizeof(struct iscsi_data));
- hdr->ttt = r2t->ttt;
- hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
- r2t->solicit_datasn++;
- hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
- memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
- hdr->itt = ctask->hdr->itt;
- hdr->exp_statsn = r2t->exp_statsn;
- new_offset = r2t->data_offset + r2t->sent;
- hdr->offset = cpu_to_be32(new_offset);
- if (left > conn->max_xmit_dlength) {
- hton24(hdr->dlength, conn->max_xmit_dlength);
- r2t->data_count = conn->max_xmit_dlength;
- } else {
- hton24(hdr->dlength, left);
- r2t->data_count = left;
- hdr->flags = ISCSI_FLAG_CMD_FINAL;
- }
- conn->dataout_pdus_cnt++;
-
- iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
- sizeof(struct iscsi_hdr));
-
- if (sc->use_sg && !iscsi_buf_left(&r2t->sendbuf)) {
- BUG_ON(tcp_ctask->bad_sg == r2t->sg);
- iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
- r2t->sg += 1;
- } else
- iscsi_buf_init_iov(&tcp_ctask->sendbuf,
- (char*)sc->request_buffer + new_offset,
- r2t->data_count);
-}
-
-static void
-iscsi_unsolicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct iscsi_data_task *dtask;
-
- dtask = tcp_ctask->dtask = &tcp_ctask->unsol_dtask;
- iscsi_prep_unsolicit_data_pdu(ctask, &dtask->hdr,
- tcp_ctask->r2t_data_count);
- iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)&dtask->hdr,
- sizeof(struct iscsi_hdr));
-}
-
-/**
- * iscsi_tcp_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
- * @conn: iscsi connection
- * @ctask: scsi command task
- * @sc: scsi command
- **/
-static void
-iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
-{
- struct scsi_cmnd *sc = ctask->sc;
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
-
- BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
-
- tcp_ctask->sent = 0;
- tcp_ctask->sg_count = 0;
-
- if (sc->sc_data_direction == DMA_TO_DEVICE) {
- tcp_ctask->xmstate = XMSTATE_W_HDR;
- tcp_ctask->exp_r2tsn = 0;
- BUG_ON(ctask->total_length == 0);
-
- if (sc->use_sg) {
- struct scatterlist *sg = sc->request_buffer;
-
- iscsi_buf_init_sg(&tcp_ctask->sendbuf,
- &sg[tcp_ctask->sg_count++]);
- tcp_ctask->sg = sg;
- tcp_ctask->bad_sg = sg + sc->use_sg;
- } else
- iscsi_buf_init_iov(&tcp_ctask->sendbuf,
- sc->request_buffer,
- sc->request_bufflen);
-
- if (ctask->imm_count)
- tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
-
- tcp_ctask->pad_count = ctask->total_length & (ISCSI_PAD_LEN-1);
- if (tcp_ctask->pad_count) {
- tcp_ctask->pad_count = ISCSI_PAD_LEN -
- tcp_ctask->pad_count;
- debug_scsi("write padding %d bytes\n",
- tcp_ctask->pad_count);
- tcp_ctask->xmstate |= XMSTATE_W_PAD;
- }
-
- if (ctask->unsol_count)
- tcp_ctask->xmstate |= XMSTATE_UNS_HDR |
- XMSTATE_UNS_INIT;
- tcp_ctask->r2t_data_count = ctask->total_length -
- ctask->imm_count -
- ctask->unsol_count;
-
- debug_scsi("cmd [itt 0x%x total %d imm %d imm_data %d "
- "r2t_data %d]\n",
- ctask->itt, ctask->total_length, ctask->imm_count,
- ctask->unsol_count, tcp_ctask->r2t_data_count);
- } else
- tcp_ctask->xmstate = XMSTATE_R_HDR;
-
- iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
- sizeof(struct iscsi_hdr));
-}
-
-/**
- * iscsi_tcp_mtask_xmit - xmit management(immediate) task
- * @conn: iscsi connection
- * @mtask: task management task
- *
- * Notes:
- * The function can return -EAGAIN in which case caller must
- * call it again later, or recover. '0' return code means successful
- * xmit.
- *
- * Management xmit state machine consists of two states:
- * IN_PROGRESS_IMM_HEAD - PDU Header xmit in progress
- * IN_PROGRESS_IMM_DATA - PDU Data xmit in progress
- **/
-static int
-iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
-{
- struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
- int rc;
-
- debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
- conn->id, tcp_mtask->xmstate, mtask->itt);
-
- if (tcp_mtask->xmstate & XMSTATE_IMM_HDR) {
- tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR;
- if (mtask->data_count)
- tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
- if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
- conn->stop_stage != STOP_CONN_RECOVER &&
- conn->hdrdgst_en)
- iscsi_hdr_digest(conn, &tcp_mtask->headbuf,
- (u8*)tcp_mtask->hdrext);
- rc = iscsi_sendhdr(conn, &tcp_mtask->headbuf,
- mtask->data_count);
- if (rc) {
- tcp_mtask->xmstate |= XMSTATE_IMM_HDR;
- if (mtask->data_count)
- tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
- return rc;
- }
- }
-
- if (tcp_mtask->xmstate & XMSTATE_IMM_DATA) {
- BUG_ON(!mtask->data_count);
- tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
- /* FIXME: implement.
- * Virtual buffer could be spreaded across multiple pages...
- */
- do {
- int rc;
-
- rc = iscsi_sendpage(conn, &tcp_mtask->sendbuf,
- &mtask->data_count, &tcp_mtask->sent);
- if (rc) {
- tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
- return rc;
- }
- } while (mtask->data_count);
- }
-
- BUG_ON(tcp_mtask->xmstate != XMSTATE_IDLE);
- if (mtask->hdr->itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
- struct iscsi_session *session = conn->session;
-
- spin_lock_bh(&session->lock);
- list_del(&conn->mtask->running);
- __kfifo_put(session->mgmtpool.queue, (void*)&conn->mtask,
- sizeof(void*));
- spin_unlock_bh(&session->lock);
- }
- return 0;
-}
-
-static inline int
-handle_xmstate_r_hdr(struct iscsi_conn *conn,
- struct iscsi_tcp_cmd_task *tcp_ctask)
-{
- int rc;