static int
iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn,
struct iscsi_task *task)
{
struct iscsi_r2t_info *r2t = &task->unsol_r2t;
struct iscsi_data hdr;
int error = 0;
/* Send data-out PDUs while there's still unsolicited data to send */
while (iscsi_task_has_unsol_data(task)) {
iscsi_prep_data_out_pdu(task, r2t, &hdr);
debug_scsi("Sending data-out: itt 0x%x, data count %d\n",
hdr.itt, r2t->data_count);
/* the buffer description has been passed with the command */
/* Send the command */
error = iser_send_data_out(conn, task, &hdr);
if (error) {
r2t->datasn--;
goto iscsi_iser_task_xmit_unsol_data_exit;
}
r2t->sent += r2t->data_count;
debug_scsi("Need to send %d more as data-out PDUs\n",
r2t->data_length - r2t->sent);
}
iscsi_iser_task_xmit_unsol_data_exit:
return error;
}
int iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
{
int ahslen;
struct iscsi_hdr *hdr;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
uint32_t cdgst, rdgst = 0;
hdr = tcp_conn->in.hdr;
/* verify PDU length */
tcp_conn->in.datalen = ntoh24(hdr->dlength);
if (tcp_conn->in.datalen > conn->max_recv_dlength) {
printk(KERN_ERR "iscsi_tcp: datalen %d > %d\n",
tcp_conn->in.datalen, conn->max_recv_dlength);
return ISCSI_ERR_DATALEN;
}
tcp_conn->data_copied = 0;
/* read AHS */
ahslen = hdr->hlength << 2;
tcp_conn->in.offset += ahslen;
tcp_conn->in.copy -= ahslen;
if (tcp_conn->in.copy < 0) {
printk(KERN_ERR "iscsi_tcp: can't handle AHS with length "
"%d bytes\n", ahslen);
return ISCSI_ERR_AHSLEN;
}
/* calculate read padding */
tcp_conn->in.padding = tcp_conn->in.datalen & (ISCSI_PAD_LEN-1);
if (tcp_conn->in.padding) {
tcp_conn->in.padding = ISCSI_PAD_LEN - tcp_conn->in.padding;
debug_scsi("read padding %d bytes\n", tcp_conn->in.padding);
}
if (conn->hdrdgst_en) {
struct scatterlist sg;
sg_init_one(&sg, (u8 *)hdr,
sizeof(struct iscsi_hdr) + ahslen);
crypto_digest_digest(tcp_conn->rx_tfm, &sg, 1, (u8 *)&cdgst);
rdgst = *(uint32_t*)((char*)hdr + sizeof(struct iscsi_hdr) +
ahslen);
if (cdgst != rdgst) {
printk(KERN_ERR "iscsi_tcp: hdrdgst error "
"recv 0x%x calc 0x%x\n", rdgst, cdgst);
return ISCSI_ERR_HDR_DGST;
}
}
return 0;
}
static int
iscsi_iser_task_xmit(struct iscsi_task *task)
{
struct iscsi_conn *conn = task->conn;
struct iscsi_iser_task *iser_task = task->dd_data;
int error = 0;
if (!task->sc)
return iscsi_iser_mtask_xmit(conn, task);
if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
BUG_ON(scsi_bufflen(task->sc) == 0);
debug_scsi("cmd [itt %x total %d imm %d unsol_data %d\n",
task->itt, scsi_bufflen(task->sc),
task->imm_count, task->unsol_r2t.data_length);
}
debug_scsi("task deq [cid %d itt 0x%x]\n",
conn->id, task->itt);
/* Send the cmd PDU */
if (!iser_task->command_sent) {
error = iser_send_command(conn, task);
if (error)
goto iscsi_iser_task_xmit_exit;
iser_task->command_sent = 1;
}
/* Send unsolicited data-out PDU(s) if necessary */
if (iscsi_task_has_unsol_data(task))
error = iscsi_iser_task_xmit_unsol_data(conn, task);
iscsi_iser_task_xmit_exit:
if (error && error != -ENOBUFS)
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return error;
}
/**
* iscsi_iser_mtask_xmit - xmit management(immediate) task
* @conn: iscsi connection
* @task: 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.
*
**/
static int
iscsi_iser_mtask_xmit(struct iscsi_conn *conn, struct iscsi_task *task)
{
int error = 0;
debug_scsi("task deq [cid %d itt 0x%x]\n", conn->id, task->itt);
error = iser_send_control(conn, task);
/* since iser xmits control with zero copy, tasks can not be recycled
* right after sending them.
* The recycling scheme is based on whether a response is expected
* - if yes, the task is recycled at iscsi_complete_pdu
* - if no, the task is recycled at iser_snd_completion
*/
if (error && error != -ENOBUFS)
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return error;
}
