- * iscsi_solicit_data_init - initialize first Data-Out
- * @conn: iscsi connection
- * @ctask: scsi command task
- * @r2t: R2T info
- *
- * Notes:
- * Initialize first Data-Out within this R2T sequence and finds
- * proper data_offset within this SCSI command.
- *
- * This function is called with connection lock taken.
- **/
-static void
-iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
- struct iscsi_r2t_info *r2t)
-{
- struct iscsi_data *hdr;
- struct scsi_cmnd *sc = ctask->sc;
- int i, sg_count = 0;
- struct scatterlist *sg;
-
- 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;
- hdr->offset = cpu_to_be32(r2t->data_offset);
- if (r2t->data_length > conn->max_xmit_dlength) {
- hton24(hdr->dlength, conn->max_xmit_dlength);
- r2t->data_count = conn->max_xmit_dlength;
- hdr->flags = 0;
- } else {
- hton24(hdr->dlength, r2t->data_length);
- r2t->data_count = r2t->data_length;
- hdr->flags = ISCSI_FLAG_CMD_FINAL;
- }
- conn->dataout_pdus_cnt++;
-
- r2t->sent = 0;
-
- iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
- sizeof(struct iscsi_hdr));
-
- sg = scsi_sglist(sc);
- r2t->sg = NULL;
- for (i = 0; i < scsi_sg_count(sc); i++, sg += 1) {
- /* FIXME: prefetch ? */
- if (sg_count + sg->length > r2t->data_offset) {
- int page_offset;
-
- /* sg page found! */
-
- /* offset within this page */
- page_offset = r2t->data_offset - sg_count;
-
- /* fill in this buffer */
- iscsi_buf_init_sg(&r2t->sendbuf, sg);
- r2t->sendbuf.sg.offset += page_offset;
- r2t->sendbuf.sg.length -= page_offset;
-
- /* xmit logic will continue with next one */
- r2t->sg = sg + 1;
- break;
- }
- sg_count += sg->length;
- }
- BUG_ON(r2t->sg == NULL);
-}
-
-/**
- * iscsi_r2t_rsp - iSCSI R2T Response processing
- * @conn: iscsi connection
- * @ctask: scsi command task
- **/
-static int
-iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
-{
- struct iscsi_r2t_info *r2t;
- struct iscsi_session *session = conn->session;
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
- int r2tsn = be32_to_cpu(rhdr->r2tsn);
- int rc;
-
- if (tcp_conn->in.datalen) {
- printk(KERN_ERR "iscsi_tcp: invalid R2t with datalen %d\n",
- tcp_conn->in.datalen);
- return ISCSI_ERR_DATALEN;
- }
-
- if (tcp_ctask->exp_datasn != r2tsn){
- debug_tcp("%s: ctask->exp_datasn(%d) != rhdr->r2tsn(%d)\n",
- __FUNCTION__, tcp_ctask->exp_datasn, r2tsn);
- return ISCSI_ERR_R2TSN;
- }
-
- /* fill-in new R2T associated with the task */
- spin_lock(&session->lock);
- iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
-
- if (!ctask->sc || ctask->mtask ||
- session->state != ISCSI_STATE_LOGGED_IN) {
- printk(KERN_INFO "iscsi_tcp: dropping R2T itt %d in "
- "recovery...\n", ctask->itt);
- spin_unlock(&session->lock);
- return 0;
- }
-
- rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
- BUG_ON(!rc);
-
- r2t->exp_statsn = rhdr->statsn;
- r2t->data_length = be32_to_cpu(rhdr->data_length);
- if (r2t->data_length == 0) {
- printk(KERN_ERR "iscsi_tcp: invalid R2T with zero data len\n");
- spin_unlock(&session->lock);
- return ISCSI_ERR_DATALEN;
- }
-
- if (r2t->data_length > session->max_burst)
- debug_scsi("invalid R2T with data len %u and max burst %u."
- "Attempting to execute request.\n",
- r2t->data_length, session->max_burst);
-
- r2t->data_offset = be32_to_cpu(rhdr->data_offset);
- if (r2t->data_offset + r2t->data_length > scsi_bufflen(ctask->sc)) {
- spin_unlock(&session->lock);
- printk(KERN_ERR "iscsi_tcp: invalid R2T with data len %u at "
- "offset %u and total length %d\n", r2t->data_length,
- r2t->data_offset, scsi_bufflen(ctask->sc));
- return ISCSI_ERR_DATALEN;
- }
-
- r2t->ttt = rhdr->ttt; /* no flip */
- r2t->solicit_datasn = 0;
-
- iscsi_solicit_data_init(conn, ctask, r2t);
-
- tcp_ctask->exp_datasn = r2tsn + 1;
- __kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
- tcp_ctask->xmstate |= XMSTATE_SOL_HDR_INIT;
- list_move_tail(&ctask->running, &conn->xmitqueue);
-
- scsi_queue_work(session->host, &conn->xmitwork);
- conn->r2t_pdus_cnt++;
- spin_unlock(&session->lock);
-
- return 0;
-}
-
-static int
-iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
-{
- int rc = 0, opcode, ahslen;
- struct iscsi_hdr *hdr;
- struct iscsi_session *session = conn->session;
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- uint32_t cdgst, rdgst = 0, itt;
-
- 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_hash_digest(&tcp_conn->rx_hash, &sg, sg.length,
- (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;
- }
- }
-
- opcode = hdr->opcode & ISCSI_OPCODE_MASK;
- /* verify itt (itt encoding: age+cid+itt) */
- rc = iscsi_verify_itt(conn, hdr, &itt);
- if (rc == ISCSI_ERR_NO_SCSI_CMD) {
- tcp_conn->in.datalen = 0; /* force drop */
- return 0;
- } else if (rc)
- return rc;
-
- debug_tcp("opcode 0x%x offset %d copy %d ahslen %d datalen %d\n",
- opcode, tcp_conn->in.offset, tcp_conn->in.copy,
- ahslen, tcp_conn->in.datalen);
-
- switch(opcode) {
- case ISCSI_OP_SCSI_DATA_IN:
- tcp_conn->in.ctask = session->cmds[itt];
- rc = iscsi_data_rsp(conn, tcp_conn->in.ctask);
- if (rc)
- return rc;
- /* fall through */
- case ISCSI_OP_SCSI_CMD_RSP:
- tcp_conn->in.ctask = session->cmds[itt];
- if (tcp_conn->in.datalen)
- goto copy_hdr;
-
- spin_lock(&session->lock);
- rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
- spin_unlock(&session->lock);
- break;
- case ISCSI_OP_R2T:
- tcp_conn->in.ctask = session->cmds[itt];
- if (ahslen)
- rc = ISCSI_ERR_AHSLEN;
- else if (tcp_conn->in.ctask->sc->sc_data_direction ==
- DMA_TO_DEVICE)
- rc = iscsi_r2t_rsp(conn, tcp_conn->in.ctask);
- else
- rc = ISCSI_ERR_PROTO;
- break;
- case ISCSI_OP_LOGIN_RSP:
- case ISCSI_OP_TEXT_RSP:
- case ISCSI_OP_REJECT:
- case ISCSI_OP_ASYNC_EVENT:
- /*
- * It is possible that we could get a PDU with a buffer larger
- * than 8K, but there are no targets that currently do this.
- * For now we fail until we find a vendor that needs it
- */
- if (ISCSI_DEF_MAX_RECV_SEG_LEN <
- tcp_conn->in.datalen) {
- printk(KERN_ERR "iscsi_tcp: received buffer of len %u "
- "but conn buffer is only %u (opcode %0x)\n",
- tcp_conn->in.datalen,
- ISCSI_DEF_MAX_RECV_SEG_LEN, opcode);
- rc = ISCSI_ERR_PROTO;
- break;
- }
-
- if (tcp_conn->in.datalen)
- goto copy_hdr;
- /* fall through */
- case ISCSI_OP_LOGOUT_RSP:
- case ISCSI_OP_NOOP_IN:
- case ISCSI_OP_SCSI_TMFUNC_RSP:
- rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
- break;
- default:
- rc = ISCSI_ERR_BAD_OPCODE;
- break;
- }
-
- return rc;
-
-copy_hdr:
- /*
- * if we did zero copy for the header but we will need multiple
- * skbs to complete the command then we have to copy the header
- * for later use
- */
- if (tcp_conn->in.zero_copy_hdr && tcp_conn->in.copy <=
- (tcp_conn->in.datalen + tcp_conn->in.padding +
- (conn->datadgst_en ? 4 : 0))) {
- debug_tcp("Copying header for later use. in.copy %d in.datalen"
- " %d\n", tcp_conn->in.copy, tcp_conn->in.datalen);
- memcpy(&tcp_conn->hdr, tcp_conn->in.hdr,
- sizeof(struct iscsi_hdr));
- tcp_conn->in.hdr = &tcp_conn->hdr;
- tcp_conn->in.zero_copy_hdr = 0;
- }
- return 0;
-}
-
-/**
- * iscsi_ctask_copy - copy skb bits to the destanation cmd task
- * @conn: iscsi tcp connection
- * @ctask: scsi command task
- * @buf: buffer to copy to
- * @buf_size: size of buffer
- * @offset: offset within the buffer
- *
- * Notes:
- * The function calls skb_copy_bits() and updates per-connection and
- * per-cmd byte counters.
- *
- * Read counters (in bytes):
- *
- * conn->in.offset offset within in progress SKB
- * conn->in.copy left to copy from in progress SKB
- * including padding
- * conn->in.copied copied already from in progress SKB
- * conn->data_copied copied already from in progress buffer
- * ctask->sent total bytes sent up to the MidLayer
- * ctask->data_count left to copy from in progress Data-In
- * buf_left left to copy from in progress buffer
- **/
-static inline int
-iscsi_ctask_copy(struct iscsi_tcp_conn *tcp_conn, struct iscsi_cmd_task *ctask,
- void *buf, int buf_size, int offset)
-{
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- int buf_left = buf_size - (tcp_conn->data_copied + offset);
- unsigned size = min(tcp_conn->in.copy, buf_left);
- int rc;
-
- size = min(size, ctask->data_count);
-
- debug_tcp("ctask_copy %d bytes at offset %d copied %d\n",
- size, tcp_conn->in.offset, tcp_conn->in.copied);
-
- BUG_ON(size <= 0);
- BUG_ON(tcp_ctask->sent + size > scsi_bufflen(ctask->sc));
-
- rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
- (char*)buf + (offset + tcp_conn->data_copied), size);
- /* must fit into skb->len */
- BUG_ON(rc);
-
- tcp_conn->in.offset += size;
- tcp_conn->in.copy -= size;
- tcp_conn->in.copied += size;
- tcp_conn->data_copied += size;
- tcp_ctask->sent += size;
- ctask->data_count -= size;
-
- BUG_ON(tcp_conn->in.copy < 0);
- BUG_ON(ctask->data_count < 0);
-
- if (buf_size != (tcp_conn->data_copied + offset)) {
- if (!ctask->data_count) {
- BUG_ON(buf_size - tcp_conn->data_copied < 0);
- /* done with this PDU */
- return buf_size - tcp_conn->data_copied;
- }
- return -EAGAIN;
- }
-
- /* done with this buffer or with both - PDU and buffer */
- tcp_conn->data_copied = 0;
- return 0;
-}
-
-/**
- * iscsi_tcp_copy - copy skb bits to the destanation buffer
- * @conn: iscsi tcp connection
- *
- * Notes:
- * The function calls skb_copy_bits() and updates per-connection
- * byte counters.
- **/
-static inline int
-iscsi_tcp_copy(struct iscsi_conn *conn, int buf_size)
-{
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- int buf_left = buf_size - tcp_conn->data_copied;
- int size = min(tcp_conn->in.copy, buf_left);
- int rc;
-
- debug_tcp("tcp_copy %d bytes at offset %d copied %d\n",
- size, tcp_conn->in.offset, tcp_conn->data_copied);
- BUG_ON(size <= 0);
-
- rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
- (char*)conn->data + tcp_conn->data_copied, size);
- BUG_ON(rc);
-
- tcp_conn->in.offset += size;
- tcp_conn->in.copy -= size;
- tcp_conn->in.copied += size;
- tcp_conn->data_copied += size;
-
- if (buf_size != tcp_conn->data_copied)
- return -EAGAIN;
-
- return 0;
-}
-
-static inline void
-partial_sg_digest_update(struct hash_desc *desc, struct scatterlist *sg,
- int offset, int length)
-{
- struct scatterlist temp;
-
- memcpy(&temp, sg, sizeof(struct scatterlist));
- temp.offset = offset;
- temp.length = length;
- crypto_hash_update(desc, &temp, length);
-}
-
-static void
-iscsi_recv_digest_update(struct iscsi_tcp_conn *tcp_conn, char* buf, int len)
-{
- struct scatterlist tmp;
-
- sg_init_one(&tmp, buf, len);
- crypto_hash_update(&tcp_conn->rx_hash, &tmp, len);
-}
-
-static int iscsi_scsi_data_in(struct iscsi_conn *conn)
-{
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- struct iscsi_cmd_task *ctask = tcp_conn->in.ctask;
- struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
- struct scsi_cmnd *sc = ctask->sc;
- struct scatterlist *sg;
- int i, offset, rc = 0;
-
- BUG_ON((void*)ctask != sc->SCp.ptr);
-
- offset = tcp_ctask->data_offset;
- sg = scsi_sglist(sc);
-
- if (tcp_ctask->data_offset)
- for (i = 0; i < tcp_ctask->sg_count; i++)
- offset -= sg[i].length;
- /* we've passed through partial sg*/
- if (offset < 0)
- offset = 0;
-
- for (i = tcp_ctask->sg_count; i < scsi_sg_count(sc); i++) {
- char *dest;
-
- dest = kmap_atomic(sg[i].page, KM_SOFTIRQ0);
- rc = iscsi_ctask_copy(tcp_conn, ctask, dest + sg[i].offset,
- sg[i].length, offset);
- kunmap_atomic(dest, KM_SOFTIRQ0);
- if (rc == -EAGAIN)
- /* continue with the next SKB/PDU */
- return rc;
- if (!rc) {
- if (conn->datadgst_en) {
- if (!offset)
- crypto_hash_update(
- &tcp_conn->rx_hash,
- &sg[i], sg[i].length);
- else
- partial_sg_digest_update(
- &tcp_conn->rx_hash,
- &sg[i],
- sg[i].offset + offset,
- sg[i].length - offset);
- }
- offset = 0;
- tcp_ctask->sg_count++;
- }
-
- if (!ctask->data_count) {
- if (rc && conn->datadgst_en)
- /*
- * data-in is complete, but buffer not...
- */
- partial_sg_digest_update(&tcp_conn->rx_hash,
- &sg[i],
- sg[i].offset,
- sg[i].length-rc);
- rc = 0;
- break;
- }
-
- if (!tcp_conn->in.copy)
- return -EAGAIN;
- }
- BUG_ON(ctask->data_count);
-
- /* check for non-exceptional status */
- if (tcp_conn->in.hdr->flags & ISCSI_FLAG_DATA_STATUS) {
- debug_scsi("done [sc %lx res %d itt 0x%x flags 0x%x]\n",
- (long)sc, sc->result, ctask->itt,
- tcp_conn->in.hdr->flags);
- spin_lock(&conn->session->lock);
- __iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
- spin_unlock(&conn->session->lock);
- }
-
- return rc;
-}
-
-static int
-iscsi_data_recv(struct iscsi_conn *conn)
-{
- struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
- int rc = 0, opcode;
-
- opcode = tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK;
- switch (opcode) {
- case ISCSI_OP_SCSI_DATA_IN:
- rc = iscsi_scsi_data_in(conn);
- break;
- case ISCSI_OP_SCSI_CMD_RSP:
- case ISCSI_OP_TEXT_RSP:
- case ISCSI_OP_LOGIN_RSP:
- case ISCSI_OP_ASYNC_EVENT:
- case ISCSI_OP_REJECT:
- /*
- * Collect data segment to the connection's data
- * placeholder
- */
- if (iscsi_tcp_copy(conn, tcp_conn->in.datalen)) {
- rc = -EAGAIN;
- goto exit;
- }
-
- rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, conn->data,
- tcp_conn->in.datalen);
- if (!rc && conn->datadgst_en && opcode != ISCSI_OP_LOGIN_RSP)
- iscsi_recv_digest_update(tcp_conn, conn->data,
- tcp_conn->in.datalen);
- break;
- default:
- BUG_ON(1);
- }
-exit:
- return rc;
-}
-
-/**
- * iscsi_tcp_data_recv - TCP receive in sendfile fashion