[ANNOUNCE 1/7] Open-iSCSI/Linux-iSCSI-5 High-Performance Initiator: iscsi-tcp.c.patch

Alex Aizman
2005-06-01T20:09:17Z

iscsi-tcp.c.patch - drivers/scsi/iscsi_tcp.c, iscsi data path.

Signed-off-by: Alex Aizman <itn780@yahoo.com>
Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>

Index: drivers/scsi/iscsi_tcp.c
===================================================================
--- /dev/null (tree:7570fde464d579ce455c865f07a613e967e9396c)
+++ uncommitted/drivers/scsi/iscsi_tcp.c (mode:100644 sha1:d76c6e022b41e5c1320fe23c12d2a754fc3513a9)
@@ -0,0 +1,2932 @@
+/*
+ * iSCSI Initiator over TCP/IP Data-Path
+ *
+ * Copyright (C) 2004 Dmitry Yusupov, Alex Aizman
+ * maintained by open-iscsi@googlegroups.com
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * See the file COPYING included with this distribution for more details.
+ *
+ * Credits:
+ * Christoph Hellwig : For reviewing the code, for comments and suggestions.
+ * Mike Christie : For reviewing the code, for comments and suggestions.
+ */
+
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/inet.h>
+#include <linux/blkdev.h>
+#include <linux/crypto.h>
+#include <linux/delay.h>
+#include <linux/kfifo.h>
+#include <linux/scatterlist.h>
+#include <net/tcp.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_request.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi.h>
+
+#include "iscsi_tcp.h"
+
+MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
+ "Alex Aizman <itn780@yahoo.com>");
+MODULE_DESCRIPTION("iSCSI/TCP data-path");
+MODULE_LICENSE("GPL");
+
+/* #define DEBUG_TCP */
+/* #define DEBUG_SCSI */
+#define DEBUG_ASSERT
+
+#ifdef DEBUG_TCP
+#define debug_tcp(fmt...) printk("tcp: " fmt)
+#else
+#define debug_tcp(fmt...)
+#endif
+
+#ifdef DEBUG_SCSI
+#define debug_scsi(fmt...) printk("scsi: " fmt)
+#else
+#define debug_scsi(fmt...)
+#endif
+
+#ifndef DEBUG_ASSERT
+#ifdef BUG_ON
+#undef BUG_ON
+#endif
+#define BUG_ON(expr)
+#endif
+
+/* global data */
+static kmem_cache_t *taskcache;
+
+static inline void
+iscsi_buf_init_virt(struct iscsi_buf *ibuf, char *vbuf, int size)
+{
+ sg_init_one(&ibuf->sg, (u8 *)vbuf, size);
+ ibuf->sent = 0;
+}
+
+static inline void
+iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
+{
+ ibuf->sg.page = sg->page;
+ ibuf->sg.offset = sg->offset;
+ ibuf->sg.length = sg->length;
+ ibuf->sent = 0;
+}
+
+static inline int
+iscsi_buf_left(struct iscsi_buf *ibuf)
+{
+ int rc;
+
+ rc = ibuf->sg.length - ibuf->sent;
+ BUG_ON(rc < 0);
+ return rc;
+}
+
+static inline void
+iscsi_buf_init_hdr(struct iscsi_conn *conn, struct iscsi_buf *ibuf,
+ char *vbuf, u8 *crc)
+{
+ iscsi_buf_init_virt(ibuf, vbuf, sizeof(struct iscsi_hdr));
+ if (conn->hdrdgst_en) {
+ crypto_digest_digest(conn->tx_tfm, &ibuf->sg, 1, crc);
+ ibuf->sg.length += sizeof(uint32_t);
+ }
+}
+
+static int
+iscsi_hdr_extract(struct iscsi_conn *conn)
+{
+ struct sk_buff *skb = conn->in.skb;
+
+ if (conn->in.copy >= conn->hdr_size &&
+ conn->in_progress != IN_PROGRESS_HEADER_GATHER) {
+ /*
+ * Zero-copy PDU Header: using connection context
+ * to store header pointer.
+ */
+ if (skb_shinfo(skb)->frag_list == NULL &&
+ !skb_shinfo(skb)->nr_frags) {
+ conn->in.hdr = (struct iscsi_hdr *)
+ ((char*)skb->data + conn->in.offset);
+ } else {
+ /* ignoring return code since we checked
+ * in.copy before */
+ skb_copy_bits(skb, conn->in.offset,
+ &conn->hdr, conn->hdr_size);
+ conn->in.hdr = &conn->hdr;
+ }
+ conn->in.offset += conn->hdr_size;
+ conn->in.copy -= conn->hdr_size;
+ conn->in.hdr_offset = 0;
+ } else {
+ int copylen;
+
+ /*
+ * PDU header scattered across SKB's,
+ * copying it... This'll happen quite rarely.
+ */
+ if (conn->in_progress == IN_PROGRESS_WAIT_HEADER) {
+ skb_copy_bits(skb, conn->in.offset,
+ &conn->hdr, conn->in.copy);
+ conn->in_progress = IN_PROGRESS_HEADER_GATHER;
+ conn->in.hdr_offset = conn->in.copy;
+ conn->in.offset += conn->in.copy;
+ conn->in.copy = 0;
+ debug_tcp("PDU gather #1 %d bytes!\n",
+ conn->in.hdr_offset);
+ return -EAGAIN;
+ }
+
+ copylen = conn->hdr_size - conn->in.hdr_offset;
+ if (copylen > conn->in.copy) {
+ printk("iscsi_tcp: PDU gather failed! "
+ "copylen %d conn->in.copy %d\n",
+ copylen, conn->in.copy);
+ iscsi_cnx_error(iscsi_handle(conn),
+ ISCSI_ERR_PDU_GATHER_FAILED);
+ return 0;
+ }
+ debug_tcp("PDU gather #2 %d bytes!\n", copylen);
+
+ skb_copy_bits(skb, conn->in.offset,
+ (char*)&conn->hdr + conn->in.hdr_offset, copylen);
+ conn->in.offset += copylen;
+ conn->in.copy -= copylen;
+ conn->in.hdr_offset = 0;
+ conn->in.hdr = &conn->hdr;
+ conn->in_progress = IN_PROGRESS_WAIT_HEADER;
+ conn->discontiguous_hdr_cnt++;
+ }
+
+ return 0;
+}
+
+static void
+iscsi_ctask_cleanup(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+{
+ struct scsi_cmnd *sc = ctask->sc;
+ struct iscsi_session *session = conn->session;
+
+ spin_lock(&session->lock);
+ if (ctask->in_progress == IN_PROGRESS_IDLE) {
+ spin_unlock(&session->lock);
+ return;
+ }
+ if (sc->sc_data_direction == DMA_TO_DEVICE) {
+ struct iscsi_data_task *dtask, *n;
+ /* WRITE: cleanup Data-Out's if any */
+ spin_lock(&conn->lock);
+ list_for_each_entry_safe(dtask, n, &ctask->dataqueue, item) {
+ list_del(&dtask->item);
+ mempool_free(dtask, ctask->datapool);
+ }
+ spin_unlock(&conn->lock);
+ }
+ sc->SCp.Status = SUCCESS;
+ ctask->in_progress = IN_PROGRESS_IDLE;
+ __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
+ spin_unlock(&session->lock);
+ conn->scsirsp_pdus_cnt++;
+}
+
+/*
+ * SCSI Command Response processing
+ */
+static int
+iscsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+{
+ int rc = 0;
+ struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)conn->in.hdr;
+ struct iscsi_session *session = conn->session;
+ struct scsi_cmnd *sc = ctask->sc;
+ int max_cmdsn = be32_to_cpu(rhdr->max_cmdsn);
+ int exp_cmdsn = be32_to_cpu(rhdr->exp_cmdsn);
+
+ if (max_cmdsn < exp_cmdsn - 1) {
+ rc = ISCSI_ERR_MAX_CMDSN;
+ sc->result = (DID_ERROR << 16);
+ goto fault;
+ }
+ session->max_cmdsn = max_cmdsn;
+ session->exp_cmdsn = exp_cmdsn;
+ conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
+
+ sc->result = (DID_OK << 16) | rhdr->cmd_status;
+
+ if (rhdr->response == ISCSI_STATUS_CMD_COMPLETED) {
+ if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION &&
+ conn->senselen) {
+ int sensecopy = min(conn->senselen,
+ SCSI_SENSE_BUFFERSIZE);
+ memcpy(sc->sense_buffer, conn->data + 2, sensecopy);
+ debug_scsi("copied %d bytes of sense\n", sensecopy);
+ }
+
+ if (sc->sc_data_direction != DMA_TO_DEVICE ) {
+ if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
+ int res_count =
+ be32_to_cpu(rhdr->residual_count);
+ if (res_count > 0 &&
+ res_count <= sc->request_bufflen) {
+ sc->resid = res_count;
+ } else {
+ sc->result = (DID_BAD_TARGET << 16) |
+ rhdr->cmd_status;
+ }
+ } else if (rhdr->flags& ISCSI_FLAG_CMD_BIDI_UNDERFLOW) {
+ sc->result = (DID_BAD_TARGET << 16) |
+ rhdr->cmd_status;
+ } else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW) {
+ sc->resid = be32_to_cpu(rhdr->residual_count);
+ }
+ }
+ } else {
+ sc->result = (DID_ERROR << 16);
+ }
+
+fault:
+ debug_scsi("done [sc %lx res %d itt 0x%x]\n",
+ (long)sc, sc->result, ctask->itt);
+ iscsi_ctask_cleanup(conn, ctask);
+ sc->scsi_done(sc);
+ return rc;
+}
+
+/*
+ * SCSI Data-In Response processing
+ */
+static int
+iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+{
+ struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)conn->in.hdr;
+ struct iscsi_session *session = conn->session;
+ int datasn = be32_to_cpu(rhdr->datasn);
+ int max_cmdsn = be32_to_cpu(rhdr->max_cmdsn);
+ int exp_cmdsn = be32_to_cpu(rhdr->exp_cmdsn);
+
+ /*
+ * setup Data-In byte counter (gets decremented..)
+ */
+ ctask->data_count = conn->in.datalen;
+
+ if (conn->in.datalen == 0)
+ return 0;
+
+ if (max_cmdsn < exp_cmdsn -1)
+ return ISCSI_ERR_MAX_CMDSN;
+
+ session->max_cmdsn = max_cmdsn;
+ session->exp_cmdsn = exp_cmdsn;
+
+ if (ctask->datasn != datasn)
+ return ISCSI_ERR_DATASN;
+
+ ctask->datasn++;
+
+ ctask->data_offset = be32_to_cpu(rhdr->offset);
+ if (ctask->data_offset + conn->in.datalen > ctask->total_length)
+ return ISCSI_ERR_DATA_OFFSET;
+
+ if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
+ struct scsi_cmnd *sc = ctask->sc;
+ conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
+ if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
+ int res_count = be32_to_cpu(rhdr->residual_count);
+ if (res_count > 0 &&
+ res_count <= sc->request_bufflen) {
+ sc->resid = res_count;
+ sc->result = (DID_OK << 16) | rhdr->cmd_status;
+ } else {
+ sc->result = (DID_BAD_TARGET << 16) |
+ rhdr->cmd_status;
+ }
+ } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW) {
+ sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
+ } else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW) {
+ sc->resid = be32_to_cpu(rhdr->residual_count);
+ sc->result = (DID_OK << 16) | rhdr->cmd_status;
+ } else {
+ sc->result = (DID_OK << 16) | rhdr->cmd_status;
+ }
+ }
+
+ conn->datain_pdus_cnt++;
+ return 0;
+}
+
+/*
+ * iscsi_solicit_data_init - initialize first Data-Out
+ *
+ * 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 iscsi_data_task *dtask;
+ struct scsi_cmnd *sc = ctask->sc;
+
+ dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
+ BUG_ON(!dtask);
+ hdr = &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;
+ hdr->lun[1] = ctask->hdr.lun[1];
+ 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_hdr(conn, &r2t->headbuf, (char*)hdr,
+ (u8 *)dtask->hdrext);
+
+ if (sc->use_sg) {
+ int i, sg_count = 0;
+ struct scatterlist *sg = sc->request_buffer;
+
+ r2t->sg = NULL;
+ for (i = 0; i < sc->use_sg; 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);
+ } else {
+ iscsi_buf_init_virt(&ctask->sendbuf,
+ (char*)sc->request_buffer + r2t->data_offset,
+ r2t->data_count);
+ }
+
+ list_add(&dtask->item, &ctask->dataqueue);
+}
+
+/*
+ * iSCSI R2T Response processing
+ */
+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_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)conn->in.hdr;
+ uint32_t max_cmdsn = be32_to_cpu(rhdr->max_cmdsn);
+ uint32_t exp_cmdsn = be32_to_cpu(rhdr->exp_cmdsn);
+ int r2tsn = be32_to_cpu(rhdr->r2tsn);
+ int rc;
+
+ if (conn->in.ahslen)
+ return ISCSI_ERR_AHSLEN;
+
+ if (conn->in.datalen)
+ return ISCSI_ERR_DATALEN;
+
+ if (ctask->exp_r2tsn && ctask->exp_r2tsn != r2tsn)
+ return ISCSI_ERR_R2TSN;
+
+ if (max_cmdsn < exp_cmdsn - 1)
+ return ISCSI_ERR_MAX_CMDSN;
+
+ session->max_cmdsn = max_cmdsn;
+ session->exp_cmdsn = exp_cmdsn;
+
+ /* FIXME: use R2TSN to detect missing R2T */
+
+ /* fill-in new R2T associated with the task */
+ rc = __kfifo_get(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 ||
+ r2t->data_length > session->max_burst)
+ return ISCSI_ERR_DATALEN;
+
+ r2t->data_offset = be32_to_cpu(rhdr->data_offset);
+ if (r2t->data_offset + r2t->data_length > ctask->total_length)
+ return ISCSI_ERR_DATALEN;
+
+ r2t->ttt = rhdr->ttt; /* no flip */
+ r2t->solicit_datasn = 0;
+
+ iscsi_solicit_data_init(conn, ctask, r2t);
+
+ ctask->exp_r2tsn = r2tsn + 1;
+ ctask->xmstate |= XMSTATE_SOL_HDR;
+ __kfifo_put(ctask->r2tqueue, (void*)&r2t, sizeof(void*));
+ __kfifo_put(conn->writequeue, (void*)&ctask, sizeof(void*));
+
+ schedule_work(&conn->xmitwork);
+ conn->r2t_pdus_cnt++;
+ return 0;
+}
+
+static int
+iscsi_hdr_recv(struct iscsi_conn *conn)
+{
+ int rc = 0;
+ struct iscsi_hdr *hdr;
+ struct iscsi_cmd_task *ctask;
+ struct iscsi_session *session = conn->session;
+ uint32_t cdgst, rdgst = 0;
+
+ hdr = conn->in.hdr;
+
+ /* verify PDU length */
+ conn->in.datalen = ntoh24(hdr->dlength);
+ if (conn->in.datalen > conn->max_recv_dlength) {
+ printk("iscsi_tcp: datalen %d > %d\n", conn->in.datalen,
+ conn->max_recv_dlength);
+ return ISCSI_ERR_DATALEN;
+ }
+ conn->data_copied = 0;
+
+ /* read AHS */
+ conn->in.ahslen = hdr->hlength*(4*sizeof(__u16));
+ conn->in.offset += conn->in.ahslen;
+ conn->in.copy -= conn->in.ahslen;
+ if (conn->in.copy < 0) {
+ printk("iscsi_tcp: can't handle AHS with length %d bytes\n",
+ conn->in.ahslen);
+ return ISCSI_ERR_AHSLEN;
+ }
+
+ /* calculate read padding */
+ conn->in.padding = conn->in.datalen & (ISCSI_PAD_LEN-1);
+ if (conn->in.padding) {
+ conn->in.padding = ISCSI_PAD_LEN - conn->in.padding;
+ debug_scsi("read padding %d bytes\n", conn->in.padding);
+ }
+
+ if (conn->hdrdgst_en) {
+ struct scatterlist sg;
+
+ sg_init_one(&sg, (u8 *)hdr,
+ sizeof(struct iscsi_hdr) + conn->in.ahslen);
+ crypto_digest_digest(conn->rx_tfm, &sg, 1, (u8 *)&cdgst);
+ rdgst = *(uint32_t*)((char*)hdr + sizeof(struct iscsi_hdr) +
+ conn->in.ahslen);
+ }
+
+ /* save opcode & itt for later */
+ conn->in.opcode = hdr->opcode;
+ conn->in.itt = be32_to_cpu(hdr->itt);
+
+ debug_tcp("opcode 0x%x offset %d copy %d ahslen %d datalen %d\n",
+ hdr->opcode, conn->in.offset, conn->in.copy,
+ conn->in.ahslen, conn->in.datalen);
+
+ if (conn->in.itt < session->cmds_max) {
+ if (conn->hdrdgst_en && cdgst != rdgst) {
+ printk("iscsi_tcp: itt %x: hdrdgst error recv 0x%x "
+ "calc 0x%x\n", conn->in.itt, rdgst, cdgst);
+ return ISCSI_ERR_HDR_DGST;
+ }
+
+ ctask = (struct iscsi_cmd_task *)session->cmds[conn->in.itt];
+ conn->in.ctask = ctask;
+
+ debug_scsi("rsp [op 0x%x cid %d sc %lx itt 0x%x len %d]\n",
+ hdr->opcode, conn->id, (long)ctask->sc, ctask->itt,
+ conn->in.datalen);
+
+ switch(conn->in.opcode) {
+ case ISCSI_OP_SCSI_CMD_RSP:
+ BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
+ if (ctask->in_progress == IN_PROGRESS_READ) {
+ if (!conn->in.datalen) {
+ rc = iscsi_cmd_rsp(conn, ctask);
+ } else {
+ /* got sense or response data;
+ * copying PDU Header to the
+ * connection's header
+ * placeholder */
+ memcpy(&conn->hdr, hdr,
+ sizeof(struct iscsi_hdr));
+ }
+ } else if (ctask->in_progress == IN_PROGRESS_WRITE) {
+ rc = iscsi_cmd_rsp(conn, ctask);
+ }
+ break;
+ case ISCSI_OP_SCSI_DATA_IN:
+ BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
+ /* save flags for non-exceptional status */
+ conn->in.flags = hdr->flags;
+ /* save cmd_status for sense data */
+ conn->in.cmd_status =
+ ((struct iscsi_data_rsp*)hdr)->cmd_status;
+ rc = iscsi_data_rsp(conn, ctask);
+ break;
+ case ISCSI_OP_R2T:
+ BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
+ rc = iscsi_r2t_rsp(conn, ctask);
+ break;
+ case ISCSI_OP_NOOP_IN:
+ case ISCSI_OP_TEXT_RSP:
+ case ISCSI_OP_LOGOUT_RSP:
+ case ISCSI_OP_ASYNC_EVENT:
+ case ISCSI_OP_REJECT:
+ /* update ExpStatSN */
+ conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+ if (!conn->in.datalen) {
+ struct iscsi_mgmt_task *mtask;
+
+ rc = iscsi_recv_pdu(iscsi_handle(conn), hdr,
+ NULL, 0);
+ mtask = (struct iscsi_mgmt_task *)
+ session->mgmt_cmds[conn->in.itt -
+ ISCSI_MGMT_ITT_OFFSET];
+ if (conn->login_mtask != mtask) {
+ spin_lock(&session->lock);
+ __kfifo_put(session->mgmtpool.queue,
+ (void*)&mtask, sizeof(void*));
+ spin_unlock(&session->lock);
+ }
+ }
+ break;
+ default:
+ rc = ISCSI_ERR_BAD_OPCODE;
+ break;
+ }
+ } else if (conn->in.itt >= ISCSI_MGMT_ITT_OFFSET &&
+ conn->in.itt < ISCSI_MGMT_ITT_OFFSET +
+ session->mgmtpool_max) {
+ struct iscsi_mgmt_task *mtask = (struct iscsi_mgmt_task *)
+ session->mgmt_cmds[conn->in.itt -
+ ISCSI_MGMT_ITT_OFFSET];
+
+ debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
+ conn->in.opcode, conn->id, mtask->itt,
+ conn->in.datalen);
+
+ switch(conn->in.opcode) {
+ case ISCSI_OP_LOGIN_RSP:
+ case ISCSI_OP_TEXT_RSP:
+ if (!conn->in.datalen) {
+ rc = iscsi_recv_pdu(iscsi_handle(conn), hdr,
+ NULL, 0);
+ if (conn->login_mtask != mtask) {
+ spin_lock(&session->lock);
+ __kfifo_put(session->mgmtpool.queue,
+ (void*)&mtask, sizeof(void*));
+ spin_unlock(&session->lock);
+ }
+ }
+ break;
+ case ISCSI_OP_SCSI_TMFUNC_RSP:
+ if (conn->in.datalen || conn->in.ahslen) {
+ rc = ISCSI_ERR_PROTO;
+ break;
+ }
+ conn->tmfrsp_pdus_cnt++;
+ spin_lock(&session->lock);
+ __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
+ sizeof(void*));
+ spin_unlock(&session->lock);
+ del_timer_sync(&conn->tmabort_timer);
+ conn->tmabort_state = ((struct iscsi_tm_rsp *)hdr)->
+ response == SCSI_TCP_TM_RESP_COMPLETE ?
+ TMABORT_SUCCESS : TMABORT_FAILED;
+ /* unblock eh_abort() and proceed with next command */
+ wake_up(&conn->ehwait);
+ break;
+ default:
+ rc = ISCSI_ERR_BAD_OPCODE;
+ break;
+ }
+ } else if (conn->in.itt == ISCSI_RESERVED_TAG) {
+ if (conn->in.opcode == ISCSI_OP_NOOP_IN &&
+ !conn->in.datalen) {
+ rc = iscsi_recv_pdu(iscsi_handle(conn), hdr, NULL, 0);
+ } else {
+ rc = ISCSI_ERR_BAD_OPCODE;
+ }
+ } else {
+ rc = ISCSI_ERR_BAD_ITT;
+ }
+
+ return rc;
+}
+
+/*
+ * iscsi_ctask_copy - copy skb bits to the destanation cmd task
+ *
+ * The function calls skb_copy_bits() and updates per-connection and
+ * per-cmd byte counters.
+ */
+static inline int
+iscsi_ctask_copy(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
+ void *buf, int buf_size)
+{
+ int buf_left = buf_size - conn->data_copied;
+ int size = min(conn->in.copy, buf_left);
+ int rc;
+
+ /*
+ * 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
+ */
+
+ size = min(size, ctask->data_count);
+
+ debug_tcp("ctask_copy %d bytes at offset %d copied %d\n",
+ size, conn->in.offset, conn->in.copied);
+
+ BUG_ON(size <= 0);
+ BUG_ON(ctask->sent + size > ctask->total_length);
+
+ rc = skb_copy_bits(conn->in.skb, conn->in.offset,
+ (char*)buf + conn->data_copied, size);
+ /* must fit into skb->len */
+ BUG_ON(rc);
+
+ conn->in.offset += size;
+ conn->in.copy -= size;
+ conn->in.copied += size;
+ conn->data_copied += size;
+ ctask->sent += size;
+ ctask->data_count -= size;
+
+ BUG_ON(conn->in.copy < 0);
+ BUG_ON(ctask->data_count < 0);
+
+ if (buf_size != conn->data_copied) {
+ if (!ctask->data_count) {
+ BUG_ON(buf_size - conn->data_copied < 0);
+ /* done with this PDU */
+ return buf_size - conn->data_copied;
+ }
+ return -EAGAIN;
+ }
+
+ /* done with this buffer or with both - PDU and buffer */
+ conn->data_copied = 0;
+ return 0;
+}
+
+/*
+ * iscsi_tcp_copy - copy skb bits to the destanation buffer
+ *
+ * The function calls skb_copy_bits() and updates per-connection byte counters.
+ */
+static inline int
+iscsi_tcp_copy(struct iscsi_conn *conn, void *buf, int buf_size)
+{
+ int buf_left = buf_size - conn->data_copied;
+ int size = min(conn->in.copy, buf_left);
+ int rc;
+
+ debug_tcp("tcp_copy %d bytes at offset %d copied %d\n",
+ size, conn->in.offset, conn->data_copied);
+ BUG_ON(size <= 0);
+
+ rc = skb_copy_bits(conn->in.skb, conn->in.offset,
+ (char*)buf + conn->data_copied, size);
+ BUG_ON(rc);
+
+ conn->in.offset += size;
+ conn->in.copy -= size;
+ conn->in.copied += size;
+ conn->data_copied += size;
+
+ if (buf_size != conn->data_copied)
+ return -EAGAIN;
+
+ return 0;
+}
+
+static int
+iscsi_data_recv(struct iscsi_conn *conn)
+{
+ struct iscsi_session *session = conn->session;
+ int rc = 0;
+
+ switch(conn->in.opcode) {
+ case ISCSI_OP_SCSI_DATA_IN: {
+ struct iscsi_cmd_task *ctask = conn->in.ctask;
+ struct scsi_cmnd *sc = ctask->sc;
+ BUG_ON(!(ctask->in_progress & IN_PROGRESS_READ &&
+ conn->in_progress == IN_PROGRESS_DATA_RECV));
+ BUG_ON((void*)ctask != sc->SCp.ptr);
+
+ /*
+ * copying Data-In into the Scsi_Cmnd
+ */
+ if (sc->use_sg) {
+ int i;
+ struct scatterlist *sg = sc->request_buffer;
+
+ for (i = ctask->sg_count; i < sc->use_sg; i++) {
+ char *dest;
+
+ dest = kmap_atomic(sg[i].page, KM_USER0);
+ rc = iscsi_ctask_copy(conn, ctask, dest + sg[i].offset,
+ sg->length);
+ kunmap_atomic(dest, KM_USER0);
+ if (rc == -EAGAIN)
+ /* continue with the next SKB/PDU */
+ goto exit;
+ if (!rc)
+ ctask->sg_count++;
+ if (!ctask->data_count) {
+ rc = 0;
+ break;
+ }
+ if (!conn->in.copy) {
+ rc = -EAGAIN;
+ goto exit;
+ }
+ }
+ } else {
+ rc = iscsi_ctask_copy(conn, ctask, sc->request_buffer,
+ sc->request_bufflen);
+ if (rc == -EAGAIN)
+ goto exit;
+ rc = 0;
+ }
+
+ /* check for non-exceptional status */
+ if (conn->in.flags & ISCSI_FLAG_DATA_STATUS) {
+ debug_scsi("done [sc %lx res %d itt 0x%x]\n",
+ (long)sc, sc->result, ctask->itt);
+ iscsi_ctask_cleanup(conn, ctask);
+ sc->scsi_done(sc);
+ }
+ }
+ break;
+ case ISCSI_OP_SCSI_CMD_RSP: {
+ /*
+ * SCSI Sense Data:
+ * copying the entire Data Segment.
+ */
+ if (iscsi_tcp_copy(conn, conn->data, conn->in.datalen)) {
+ rc = -EAGAIN;
+ goto exit;
+ }
+
+ /*
+ * check for sense
+ */
+ conn->in.hdr = &conn->hdr;
+ conn->senselen = (conn->data[0] << 8) | conn->data[1];
+ rc = iscsi_cmd_rsp(conn, conn->in.ctask);
+ }
+ break;
+ case ISCSI_OP_TEXT_RSP:
+ case ISCSI_OP_LOGIN_RSP:
+ case ISCSI_OP_NOOP_IN: {
+ struct iscsi_mgmt_task *mtask = NULL;
+
+ if (conn->in.itt != ISCSI_RESERVED_TAG) {
+ mtask = (struct iscsi_mgmt_task *)
+ session->mgmt_cmds[conn->in.itt -
+ ISCSI_MGMT_ITT_OFFSET];
+ }
+
+ /*
+ * Collect data segment to the connection's data
+ * placeholder
+ */
+ if (iscsi_tcp_copy(conn, conn->data, conn->in.datalen)) {
+ rc = -EAGAIN;
+ goto exit;
+ }
+
+ rc = iscsi_recv_pdu(iscsi_handle(conn), conn->in.hdr,
+ conn->data, conn->in.datalen);
+
+ if (mtask && conn->login_mtask != mtask) {
+ spin_lock(&session->lock);
+ __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
+ sizeof(void*));
+ spin_unlock(&session->lock);
+ }
+ }
+ break;
+ default:
+ BUG_ON(1);
+ }
+exit:
+ return rc;
+}
+
+/*
+ * TCP receive
+ */
+static int
+iscsi_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
+ unsigned int offset, size_t len)
+{
+ int rc;
+ struct iscsi_conn *conn = rd_desc->arg.data;
+ int start = skb_headlen(skb);
+ int processed;
+
+ /*
+ * Save current SKB and its offset in the corresponding
+ * connection context.
+ */
+ conn->in.copy = start - offset;
+ conn->in.offset = offset;
+ conn->in.skb = skb;
+ conn->in.len = conn->in.copy;
+ BUG_ON(conn->in.copy <= 0);
+ debug_tcp("in %d bytes\n", conn->in.copy);
+
+more:
+ conn->in.copied = 0;
+ rc = 0;
+
+ if (conn->in_progress == IN_PROGRESS_WAIT_HEADER ||
+ conn->in_progress == IN_PROGRESS_HEADER_GATHER) {
+ rc = iscsi_hdr_extract(conn);
+ if (rc) {
+ if (rc == -EAGAIN)
+ goto nomore;
+ else {
+ iscsi_cnx_error(iscsi_handle(conn), rc);
+ return 0;
+ }
+ }
+
+ /*
+ * Verify and process incoming PDU header.
+ */
+ rc = iscsi_hdr_recv(conn);
+ if (!rc && conn->in.datalen) {
+ conn->in_progress = IN_PROGRESS_DATA_RECV;
+ } else if (rc) {
+ iscsi_cnx_error(iscsi_handle(conn), rc);
+ return 0;
+ }
+ }
+
+ if (conn->in_progress == IN_PROGRESS_DATA_RECV &&
+ conn->in.copy) {
+
+ debug_tcp("data_recv offset %d copy %d\n",
+ conn->in.offset, conn->in.copy);
+
+ rc = iscsi_data_recv(conn);
+ if (rc) {
+ if (rc == -EAGAIN) {
+ rd_desc->count = conn->in.datalen -
+ conn->in.ctask->sent;
+ goto again;
+ }
+ iscsi_cnx_error(iscsi_handle(conn), rc);
+ return 0;
+ }
+ conn->in.copy -= conn->in.padding;
+ conn->in.offset += conn->in.padding;
+ conn->in_progress = IN_PROGRESS_WAIT_HEADER;
+ }
+
+ debug_tcp("f, processed %d from out of %d padding %d\n",
+ conn->in.offset - offset, (int)len, conn->in.padding);
+ BUG_ON(conn->in.offset - offset > len);
+
+ if (conn->in.offset - offset != len) {
+ debug_tcp("continue to process %d bytes\n",
+ (int)len - (conn->in.offset - offset));
+ goto more;
+ }
+
+nomore:
+ processed = conn->in.offset - offset;
+ BUG_ON(processed == 0);
+ return processed;
+
+again:
+ processed = conn->in.offset - offset;
+ debug_tcp("c, processed %d from out of %d rd_desc_cnt %d\n",
+ processed, (int)len, (int)rd_desc->count);
+ BUG_ON(processed == 0);
+ BUG_ON(processed > len);
+
+ conn->rxdata_octets += processed;
+ return processed;
+}
+
+static void
+iscsi_tcp_data_ready(struct sock *sk, int flag)
+{
+ struct iscsi_conn *conn = sk->sk_user_data;
+ read_descriptor_t rd_desc;
+
+ read_lock(&sk->sk_callback_lock);
+
+ /* use rd_desc to pass 'conn' to iscsi_tcp_data_recv */
+ rd_desc.arg.data = conn;
+ rd_desc.count = 0;
+ tcp_read_sock(sk, &rd_desc, iscsi_tcp_data_recv);
+
+ read_unlock(&sk->sk_callback_lock);
+}
+
+static void
+iscsi_tcp_state_change(struct sock *sk)
+{
+ struct iscsi_conn *conn;
+ struct iscsi_session *session;
+ void (*old_state_change)(struct sock *);
+
+ read_lock(&sk->sk_callback_lock);
+
+ conn = (struct iscsi_conn*)sk->sk_user_data;
+ session = conn->session;
+
+ if (sk->sk_state == TCP_CLOSE_WAIT ||
+ sk->sk_state == TCP_CLOSE) {
+ debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
+ conn->c_stage = ISCSI_CNX_CLEANUP_WAIT;
+ spin_lock_bh(&session->conn_lock);
+ if (session->conn_cnt == 1 ||
+ session->leadconn == conn) {
+ session->state = ISCSI_STATE_FAILED;
+ }
+ spin_unlock_bh(&session->conn_lock);
+ iscsi_cnx_error(iscsi_handle(conn), ISCSI_ERR_CNX_FAILED);
+ }
+
+ old_state_change = conn->old_state_change;
+
+ read_unlock(&sk->sk_callback_lock);
+
+ old_state_change(sk);
+}
+
+/*
+ * Called when more output buffer space is available for this socket.
+ */
+static void
+iscsi_write_space(struct sock *sk)
+{
+ struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
+ conn->old_write_space(sk);
+ debug_tcp("iscsi_write_space: cid %d\n", conn->id);
+ conn->suspend = 0;
+ schedule_work(&conn->xmitwork);
+}
+
+static void
+iscsi_conn_set_callbacks(struct iscsi_conn *conn)
+{
+ struct sock *sk = conn->sock->sk;
+
+ /* assign new callbacks */
+ write_lock_bh(&sk->sk_callback_lock);
+ sk->sk_user_data = conn;
+ conn->old_data_ready = sk->sk_data_ready;
+ conn->old_state_change = sk->sk_state_change;
+ 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_conn *conn)
+{
+ struct sock *sk = 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 = conn->old_data_ready;
+ sk->sk_state_change = conn->old_state_change;
+ sk->sk_write_space = conn->old_write_space;
+ sk->sk_no_check = 0;
+ write_unlock_bh(&sk->sk_callback_lock);
+}
+
+/*
+ * iscsi_sendhdr - send PDU Header via tcp_sendpage()
+ * (Tx, Fast Path)
+ */
+static inline int
+iscsi_sendhdr(struct iscsi_conn *conn, struct iscsi_buf *buf, int datalen)
+{
+ struct socket *sk = conn->sock;
+ int flags = 0; /* MSG_DONTWAIT; */
+ int res, offset, size;
+
+ offset = buf->sg.offset + buf->sent;
+ 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;
+
+ /* sendpage */
+ res = sk->ops->sendpage(sk, buf->sg.page, offset, size, flags);
+ debug_tcp("sendhdr %p %d bytes at offset %d sent %d res %d\n",
+ page_address(buf->sg.page), size, offset, buf->sent, res);
+ if (res >= 0) {
+ conn->txdata_octets += res;
+ buf->sent += res;
+ if (size != res)
+ return -EAGAIN;
+ return 0;
+ } else if (res == -EAGAIN) {
+ conn->sendpage_failures_cnt++;
+ conn->suspend = 1;
+ } else if (res == -EPIPE) {
+ conn->suspend = 1;
+ iscsi_cnx_error(iscsi_handle(conn), ISCSI_ERR_CNX_FAILED);
+ }
+
+ return res;
+}
+
+/*
+ * iscsi_sendpage - send one page of iSCSI Data-Out.
+ * (Tx, Fast Path)
+ */
+static inline int
+iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
+ int *count, int *sent)
+{
+ ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
+ struct socket *sk = conn->sock;
+ int flags = 0; /* MSG_DONTWAIT; */
+ int res, offset, 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)
+ flags |= MSG_MORE;
+
+ offset = buf->sg.offset + buf->sent;
+
+ /* tcp_sendpage */
+ sendpage = sk->ops->sendpage ? : sock_no_sendpage;
+
+ res = sendpage(sk, buf->sg.page, offset, size, flags);
+ debug_tcp("sendpage %p %d bytes, boff %d bsent %d "
+ "left %d sent %d res %d\n",
+ page_address(buf->sg.page), size, offset,
+ buf->sent, *count, *sent, res);
+ if (res >= 0) {
+ conn->txdata_octets += res;
+ buf->sent += res;
+ *count -= res;
+ *sent += res;
+ if (size != res)
+ return -EAGAIN;
+ return 0;
+ } else if (res == -EAGAIN) {
+ conn->sendpage_failures_cnt++;
+ conn->suspend = 1;
+ } else if (res == -EPIPE) {
+ conn->suspend = 1;
+ iscsi_cnx_error(iscsi_handle(conn), ISCSI_ERR_CNX_FAILED);
+ }
+
+ return res;
+}
+
+/*
+ * iscsi_solicit_data_cont - initialize next Data-Out
+ *
+ * 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_data *hdr;
+ struct iscsi_data_task *dtask;
+ struct scsi_cmnd *sc = ctask->sc;
+ int new_offset;
+
+ dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
+ BUG_ON(!dtask);
+ hdr = &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;
+ hdr->lun[1] = ctask->hdr.lun[1];
+ 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_hdr(conn, &r2t->headbuf, (char*)hdr,
+ (u8 *)dtask->hdrext);
+
+ if (sc->use_sg) {
+ if (!iscsi_buf_left(&r2t->sendbuf)) {
+ BUG_ON(ctask->bad_sg == r2t->sg);
+ iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
+ r2t->sg += 1;
+ }
+ } else {
+ iscsi_buf_init_virt(&ctask->sendbuf,
+ (char*)sc->request_buffer + new_offset,
+ r2t->data_count);
+ }
+
+ list_add(&dtask->item, &ctask->dataqueue);
+}
+
+static void
+iscsi_unsolicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+{
+ struct iscsi_data *hdr;
+ struct iscsi_data_task *dtask;
+
+ dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
+ BUG_ON(!dtask);
+ hdr = &dtask->hdr;
+ memset(hdr, 0, sizeof(struct iscsi_data));
+ hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
+ hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
+ ctask->unsol_datasn++;
+ hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
+ hdr->lun[1] = ctask->hdr.lun[1];
+ hdr->itt = ctask->hdr.itt;
+ hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
+ hdr->offset = cpu_to_be32(ctask->total_length -
+ ctask->r2t_data_count -
+ ctask->unsol_count);
+ if (ctask->unsol_count > conn->max_xmit_dlength) {
+ hton24(hdr->dlength, conn->max_xmit_dlength);
+ ctask->data_count = conn->max_xmit_dlength;
+ hdr->flags = 0;
+ } else {
+ hton24(hdr->dlength, ctask->unsol_count);
+ ctask->data_count = ctask->unsol_count;
+ hdr->flags = ISCSI_FLAG_CMD_FINAL;
+ }
+
+ iscsi_buf_init_hdr(conn, &ctask->headbuf, (char*)hdr,
+ (u8 *)dtask->hdrext);
+
+ list_add(&dtask->item, &ctask->dataqueue);
+}
+
+/*
+ * Initialize iSCSI SCSI_READ or SCSI_WRITE commands
+ */
+static void
+iscsi_cmd_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
+ struct scsi_cmnd *sc)
+{
+ struct iscsi_session *session = conn->session;
+
+ ctask->sc = sc;
+ ctask->conn = conn;
+ ctask->hdr.opcode = ISCSI_OP_SCSI_CMD;
+ ctask->hdr.flags = ISCSI_ATTR_SIMPLE;
+ ctask->hdr.lun[1] = sc->device->lun;
+ ctask->hdr.itt = cpu_to_be32(ctask->itt);
+ ctask->hdr.data_length = cpu_to_be32(sc->request_bufflen);
+ ctask->hdr.cmdsn = cpu_to_be32(session->cmdsn); session->cmdsn++;
+ ctask->hdr.exp_statsn = cpu_to_be32(conn->exp_statsn);
+ memcpy(ctask->hdr.cdb, sc->cmnd, sc->cmd_len);
+ memset(&ctask->hdr.cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
+
+ ctask->in_progress = IN_PROGRESS_IDLE;
+ ctask->sent = 0;
+ ctask->sg_count = 0;
+
+ ctask->total_length = sc->request_bufflen;
+
+ if (sc->sc_data_direction == DMA_TO_DEVICE) {
+ ctask->exp_r2tsn = 0;
+ ctask->hdr.flags |= ISCSI_FLAG_CMD_WRITE;
+ ctask->in_progress = IN_PROGRESS_WRITE;
+ BUG_ON(ctask->total_length == 0);
+ if (sc->use_sg) {
+ struct scatterlist *sg = sc->request_buffer;
+
+ iscsi_buf_init_sg(&ctask->sendbuf,
+ &sg[ctask->sg_count++]);
+ ctask->sg = sg;
+ ctask->bad_sg = sg + sc->use_sg;
+ } else {
+ iscsi_buf_init_virt(&ctask->sendbuf, sc->request_buffer,
+ sc->request_bufflen);
+ BUG_ON(sc->request_bufflen > PAGE_SIZE);
+ }
+
+ /*
+ * Write counters:
+ *
+ * imm_count bytes to be sent right after
+ * SCSI PDU Header
+ *
+ * unsol_count bytes(as Data-Out) to be sent
+ * without R2T ack right after
+ * immediate data
+ *
+ * r2t_data_count bytes to be sent via R2T ack's
+ *
+ * pad_count bytes to be sent as zero-padding
+ */
+ ctask->imm_count = 0;
+ ctask->unsol_count = 0;
+ ctask->unsol_datasn = 0;
+ ctask->xmstate = XMSTATE_W_HDR;
+ /* calculate write padding */
+ ctask->pad_count = ctask->total_length & (ISCSI_PAD_LEN-1);
+ if (ctask->pad_count) {
+ ctask->pad_count = ISCSI_PAD_LEN - ctask->pad_count;
+ debug_scsi("write padding %d bytes\n",
+ ctask->pad_count);
+ ctask->xmstate |= XMSTATE_W_PAD;
+ }
+ if (session->imm_data_en) {
+ if (ctask->total_length >= session->first_burst) {
+ ctask->imm_count = min(session->first_burst,
+ conn->max_xmit_dlength);
+ } else {
+ ctask->imm_count = min(ctask->total_length,
+ conn->max_xmit_dlength);
+ }
+ hton24(ctask->hdr.dlength, ctask->imm_count);
+ ctask->xmstate |= XMSTATE_IMM_DATA;
+ } else {
+ zero_data(ctask->hdr.dlength);
+ }
+ if (!session->initial_r2t_en)
+ ctask->unsol_count = min(session->first_burst,
+ ctask->total_length) - ctask->imm_count;
+ if (!ctask->unsol_count) {
+ /* No unsolicit Data-Out's */
+ ctask->hdr.flags |= ISCSI_FLAG_CMD_FINAL;
+ } else {
+ ctask->xmstate |= XMSTATE_UNS_HDR | XMSTATE_UNS_INIT;
+ }
+ ctask->r2t_data_count = ctask->total_length -
+ ctask->imm_count -
+ ctask->unsol_count;
+
+ debug_scsi("cmd [itt %x total %d imm %d imm_data %d "
+ "r2t_data %d]\n",
+ ctask->itt, ctask->total_length, ctask->imm_count,
+ ctask->unsol_count, ctask->r2t_data_count);
+ } else {
+ ctask->hdr.flags |= ISCSI_FLAG_CMD_FINAL;
+ if (sc->sc_data_direction == DMA_FROM_DEVICE)
+ ctask->hdr.flags |= ISCSI_FLAG_CMD_READ;
+ ctask->datasn = 0;
+ ctask->in_progress = IN_PROGRESS_READ;
+ ctask->xmstate = XMSTATE_R_HDR;
+ zero_data(ctask->hdr.dlength);
+ }
+
+ iscsi_buf_init_hdr(conn, &ctask->headbuf, (char*)&ctask->hdr,
+ (u8 *)ctask->hdrext);
+ conn->scsicmd_pdus_cnt++;
+}
+
+/*
+ * iscsi_mtask_xmit - xmit management(immediate) task
+ *
+ * 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_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
+{
+
+ debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
+ conn->id, mtask->xmstate, mtask->itt);
+
+ if (mtask->xmstate & XMSTATE_IMM_HDR) {
+ mtask->xmstate &= ~XMSTATE_IMM_HDR;
+ if (mtask->data_count)
+ mtask->xmstate |= XMSTATE_IMM_DATA;
+ if (iscsi_sendhdr(conn, &mtask->headbuf, mtask->data_count)) {
+ mtask->xmstate |= XMSTATE_IMM_HDR;
+ if (mtask->data_count)
+ mtask->xmstate &= ~XMSTATE_IMM_DATA;
+ return -EAGAIN;
+ }
+ }
+
+ if (mtask->xmstate & XMSTATE_IMM_DATA) {
+ BUG_ON(!mtask->data_count);
+ mtask->xmstate &= ~XMSTATE_IMM_DATA;
+ /* FIXME: implement.
+ * Virtual buffer could be spreaded across multiple pages...
+ */
+ do {
+ if (iscsi_sendpage(conn, &mtask->sendbuf,
+ &mtask->data_count, &mtask->sent)) {
+ mtask->xmstate |= XMSTATE_IMM_DATA;
+ return -EAGAIN;
+ }
+ } while (mtask->data_count);
+ }
+
+ BUG_ON(mtask->xmstate != XMSTATE_IDLE);
+ return 0;
+}
+
+static int
+iscsi_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
+{
+ struct iscsi_r2t_info *r2t = NULL;
+
+ debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
+ conn->id, ctask->xmstate, ctask->itt);
+
+ if (ctask->xmstate & XMSTATE_R_HDR) {
+ ctask->xmstate &= ~XMSTATE_R_HDR;
+ if (!iscsi_sendhdr(conn, &ctask->headbuf, 0)) {
+ BUG_ON(ctask->xmstate != XMSTATE_IDLE);
+ return 0; /* wait for Data-In */
+ }
+ ctask->xmstate |= XMSTATE_R_HDR;
+ return -EAGAIN;
+ }
+
+ if (ctask->xmstate & XMSTATE_W_HDR) {
+ ctask->xmstate &= ~XMSTATE_W_HDR;
+ if (iscsi_sendhdr(conn, &ctask->headbuf, ctask->imm_count)) {
+ ctask->xmstate |= XMSTATE_W_HDR;
+ return -EAGAIN;
+ }
+ }
+
+ if (ctask->xmstate & XMSTATE_IMM_DATA) {
+ BUG_ON(!ctask->imm_count);
+ ctask->xmstate &= ~XMSTATE_IMM_DATA;
+ for (;;) {
+ if (iscsi_sendpage(conn, &ctask->sendbuf,
+ &ctask->imm_count, &ctask->sent)) {
+ ctask->xmstate |= XMSTATE_IMM_DATA;
+ return -EAGAIN;
+ }
+ if (!ctask->imm_count)
+ break;
+ iscsi_buf_init_sg(&ctask->sendbuf,
+ &ctask->sg[ctask->sg_count++]);
+ }
+ }
+
+ if (ctask->xmstate & XMSTATE_UNS_HDR) {
+ BUG_ON(!ctask->unsol_count);
+ ctask->xmstate &= ~XMSTATE_UNS_HDR;
+_unsolicit_head_again:
+ ctask->xmstate |= XMSTATE_UNS_DATA;
+ if (ctask->xmstate & XMSTATE_UNS_INIT) {
+ iscsi_unsolicit_data_init(conn, ctask);
+ ctask->xmstate &= ~XMSTATE_UNS_INIT;
+ }
+ if (iscsi_sendhdr(conn, &ctask->headbuf, ctask->data_count)) {
+ ctask->xmstate &= ~XMSTATE_UNS_DATA;
+ ctask->xmstate |= XMSTATE_UNS_HDR;
+ return -EAGAIN;
+ }
+
+ debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
+ ctask->itt, ctask->unsol_count, ctask->sent);
+ }
+
+ if (ctask->xmstate & XMSTATE_UNS_DATA) {
+ BUG_ON(!ctask->data_count);
+ ctask->xmstate &= ~XMSTATE_UNS_DATA;
+ for (;;) {
+ int start = ctask->sent;
+ if (iscsi_sendpage(conn, &ctask->sendbuf,
+ &ctask->data_count,
+ &ctask->sent)) {
+ ctask->unsol_count -= ctask->sent - start;
+ ctask->xmstate |= XMSTATE_UNS_DATA;
+ /* will continue with this ctask later.. */
+ return -EAGAIN;
+ }
+ BUG_ON(ctask->sent > ctask->total_length);
+ ctask->unsol_count -= ctask->sent - start;
+ if (!ctask->data_count)
+ break;
+ iscsi_buf_init_sg(&ctask->sendbuf,
+ &ctask->sg[ctask->sg_count++]);
+ }
+ BUG_ON(ctask->unsol_count < 0);
+
+ /*
+ * Done with the Data-Out. Next, check if we need
+ * to send another unsolicited Data-Out.
+ */
+ if (ctask->unsol_count) {
+ ctask->xmstate |= XMSTATE_UNS_INIT;
+ goto _unsolicit_head_again;
+ }
+
+ goto _done;
+ }
+
+ if (ctask->xmstate & XMSTATE_SOL_HDR) {
+ ctask->xmstate &= ~XMSTATE_SOL_HDR;
+ ctask->xmstate |= XMSTATE_SOL_DATA;
+ if (!ctask->r2t) {
+ __kfifo_get(ctask->r2tqueue, (void*)&r2t,
+ sizeof(void*));
+ ctask->r2t = r2t;
+ }
+_solicit_head_again:
+ BUG_ON(r2t == NULL);
+ if (iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count)) {
+ ctask->xmstate &= ~XMSTATE_SOL_DATA;
+ ctask->xmstate |= XMSTATE_SOL_HDR;
+ return -EAGAIN;
+ }
+
+ debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
+ r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
+ r2t->sent);
+ }
+
+ if (ctask->xmstate & XMSTATE_SOL_DATA) {
+ int left;
+
+ ctask->xmstate &= ~XMSTATE_SOL_DATA;
+ r2t = ctask->r2t;
+_solicit_again:
+ /*
+ * send Data-Out whitnin this R2T sequence.
+ */
+ if (r2t->data_count) {
+ if (iscsi_sendpage(conn, &r2t->sendbuf,
+ &r2t->data_count,
+ &r2t->sent)) {
+ ctask->xmstate |= XMSTATE_SOL_DATA;
+ /* will continue with this ctask later.. */
+ return -EAGAIN;
+ }
+ BUG_ON(r2t->data_count < 0);
+ if (r2t->data_count) {
+ BUG_ON(ctask->sc->use_sg == 0);
+ if (!iscsi_buf_left(&r2t->sendbuf)) {
+ BUG_ON(ctask->bad_sg == r2t->sg);
+ iscsi_buf_init_sg(&r2t->sendbuf,
+ r2t->sg);
+ r2t->sg += 1;
+ }
+ goto _solicit_again;
+ }
+ }
+
+ /*
+ * Done with this Data-Out. Next, check if we have
+ * to send another Data-Out for this R2T.
+ */
+ BUG_ON(r2t->data_length - r2t->sent < 0);
+ left = r2t->data_length - r2t->sent;
+ if (left) {
+ iscsi_solicit_data_cont(conn, ctask, r2t, left);
+ ctask->xmstate |= XMSTATE_SOL_DATA;
+ ctask->xmstate &= ~XMSTATE_SOL_HDR;
+ goto _solicit_head_again;
+ }
+
+ /*
+ * Done with this R2T. Check if there are more
+ * outstanding R2Ts ready to be processed.
+ */
+ BUG_ON(ctask->r2t_data_count - r2t->data_length < 0);
+ ctask->r2t_data_count -= r2t->data_length;
+ ctask->r2t = NULL;
+ __kfifo_put(ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
+ if (__kfifo_get(ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
+ ctask->r2t = r2t;
+ ctask->xmstate |= XMSTATE_SOL_DATA;
+ ctask->xmstate &= ~XMSTATE_SOL_HDR;
+ goto _solicit_head_again;
+ }
+ }
+
+_done:
+ /*
+ * Last thing to check is whether we need to send write
+ * padding. Note that we check for xmstate equality, not just the bit.
+ */
+ if (ctask->xmstate == XMSTATE_W_PAD) {
+ int sent;
+ ctask->xmstate &= ~XMSTATE_W_PAD;
+ iscsi_buf_init_virt(&ctask->sendbuf, (char*)&ctask->pad,
+ ctask->pad_count);
+ if (iscsi_sendpage(conn, &ctask->sendbuf, &ctask->pad_count,
+ &sent)) {
+ ctask->xmstate |= XMSTATE_W_PAD;
+ return -EAGAIN;
+ }
+ }
+ return 0;
+}
+
+/*
+ * iscsi_data_xmit - xmit any command into the scheduled connection
+ *
+ * The function can return -EAGAIN in which case the caller must
+ * re-schedule it again later or recover. '0' return code means successful
+ * xmit.
+ */
+static int
+iscsi_data_xmit(struct iscsi_conn *conn)
+{
+ /*
+ * Transmit in the following order:
+ *
+ * 1) un-finished xmit (ctask or mtask)
+ * 2) immediate control PDUs
+ * 3) write data
+ * 4) SCSI commands
+ * 5) non-immediate control PDUs
+ *
+ * No need to lock around __kfifo_get as long as
+ * there's one producer and one consumer.
+ */
+
+ BUG_ON(conn->ctask && conn->mtask);
+
+ if (conn->ctask) {
+ if (iscsi_ctask_xmit(conn, conn->ctask))
+ return -EAGAIN;
+ /* done with this in-progress ctask */
+ conn->ctask = NULL;
+ }
+ if (conn->mtask) {
+ if (iscsi_mtask_xmit(conn, conn->mtask))
+ return -EAGAIN;
+ /* done with this in-progress mtask */
+ conn->mtask = NULL;
+ }
+
+ /* process immediate first */
+ if (unlikely(__kfifo_len(conn->immqueue))) {
+ struct iscsi_session *session = conn->session;
+ while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
+ sizeof(void*))) {
+ if (iscsi_mtask_xmit(conn, conn->mtask))
+ return -EAGAIN;
+
+ if (conn->mtask->hdr.itt ==
+ cpu_to_be32(ISCSI_RESERVED_TAG)) {
+ spin_lock_bh(&session->lock);
+ __kfifo_put(session->mgmtpool.queue,
+ (void*)&conn->mtask, sizeof(void*));
+ spin_unlock_bh(&session->lock);
+ }
+ }
+ /* done with this mtask */
+ conn->mtask = NULL;
+ }
+
+ /* process write queue */
+ while (__kfifo_get(conn->writequeue, (void*)&conn->ctask,
+ sizeof(void*))) {
+ if (iscsi_ctask_xmit(conn, conn->ctask))
+ return -EAGAIN;
+ }
+
+ /* process command queue */
+ while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
+ sizeof(void*))) {
+ if (iscsi_ctask_xmit(conn, conn->ctask))
+ return -EAGAIN;
+ }
+ /* done with this ctask */
+ conn->ctask = NULL;
+
+ /* process the rest control plane PDUs, if any */
+ if (unlikely(__kfifo_len(conn->mgmtqueue))) {
+ struct iscsi_session *session = conn->session;
+ while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
+ sizeof(void*))) {
+ if (iscsi_mtask_xmit(conn, conn->mtask))
+ return -EAGAIN;
+
+ if (conn->mtask->hdr.itt ==
+ cpu_to_be32(ISCSI_RESERVED_TAG)) {
+ spin_lock_bh(&session->lock);
+ __kfifo_put(session->mgmtpool.queue,
+ (void*)&conn->mtask,
+ sizeof(void*));
+ spin_unlock_bh(&session->lock);
+ }
+ }
+ /* done with this mtask */
+ conn->mtask = NULL;
+ }
+
+ return 0;
+}
+
+static inline int
+iscsi_data_xmit_more(struct iscsi_conn *conn)
+{
+ int rc;
+
+ if (unlikely(conn->suspend))
+ return 0;
+ rc = iscsi_data_xmit(conn);
+ if (rc) {
+ if (conn->stop_stage != STOP_CNX_RECOVER &&
+ (conn->c_stage == ISCSI_CNX_CLEANUP_WAIT ||
+ conn->c_stage == ISCSI_CNX_STOPPED ||
+ conn->suspend))
+ return 0;
+ }
+ return rc;
+}
+
+static void
+iscsi_xmitworker(void *data)
+{
+ struct iscsi_conn *conn = data;
+
+ /*
+ * serialize Xmit worker on a per-connection basis.
+ */
+ down(&conn->xmitsema);
+ if (iscsi_data_xmit_more(conn))
+ schedule_work(&conn->xmitwork);
+ up(&conn->xmitsema);
+}
+
+#define FAILURE_BAD_HOST 1
+#define FAILURE_SESSION_FAILED 2
+#define FAILURE_SESSION_FREED 3
+#define FAILURE_WINDOW_CLOSED 4
+#define FAILURE_SESSION_TERMINATE 5
+
+static int
+iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
+{
+ struct Scsi_Host *host;
+ int reason = 0;
+ struct iscsi_session *session;
+ struct iscsi_conn *conn = NULL;
+ struct iscsi_cmd_task *ctask = NULL;
+
+ sc->scsi_done = done;
+ sc->result = 0;
+
+ host = sc->device->host;
+ session = iscsi_hostdata(host->hostdata);
+ BUG_ON(host != session->host);
+
+ spin_lock(&session->lock);
+
+ if (session->state != ISCSI_STATE_LOGGED_IN) {
+ if (session->state == ISCSI_STATE_FAILED) {
+ reason = FAILURE_SESSION_FAILED;
+ goto reject;
+ } else if (session->state == ISCSI_STATE_TERMINATE) {
+ reason = FAILURE_SESSION_TERMINATE;
+ goto fault;
+ }
+ reason = FAILURE_SESSION_FREED;
+ goto fault;
+ }
+
+ /*
+ * Check for iSCSI window and take care of CmdSN wrap-around
+ */
+ if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
+ reason = FAILURE_WINDOW_CLOSED;
+ goto reject;
+ }
+
+ conn = session->leadconn;
+
+ if (unlikely(session->conn_cnt > 1)) {
+ struct iscsi_conn *cnx;
+ int cpu = smp_processor_id();
+
+ spin_lock(&session->conn_lock);
+ list_for_each_entry(cnx, &session->connections, item) {
+ if (cnx->cpu == cpu && cpu_online(cpu)) {
+ conn = cnx;
+ break;
+ }
+ }
+ spin_unlock(&session->conn_lock);
+ }
+
+ __kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
+ sc->SCp.Status = QUEUED;
+ sc->SCp.phase = session->generation;
+ spin_unlock(&session->lock);
+
+ BUG_ON(!ctask);
+ BUG_ON(ctask->in_progress = IN_PROGRESS_IDLE);
+
+ sc->SCp.ptr = (char*)ctask;
+ iscsi_cmd_init(conn, ctask, sc);
+
+ __kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
+ debug_scsi(
+ "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
+ sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
+ conn->id, (long)sc, ctask->itt, sc->request_bufflen,
+ session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
+
+ if (!in_interrupt() && !down_trylock(&conn->xmitsema)) {
+ spin_unlock_irq(host->host_lock);
+ if (iscsi_data_xmit_more(conn))
+ schedule_work(&conn->xmitwork);
+ up(&conn->xmitsema);
+ spin_lock_irq(host->host_lock);
+ } else
+ schedule_work(&conn->xmitwork);
+
+ return 0;
+
+reject:
+ spin_unlock(&session->lock);
+ debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
+ return SCSI_MLQUEUE_HOST_BUSY;
+
+fault:
+ spin_unlock(&session->lock);
+ printk("iscsi_tcp: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
+ sc->sense_buffer[0] = 0x70;
+ sc->sense_buffer[2] = NOT_READY;
+ sc->sense_buffer[7] = 0x6;
+ sc->sense_buffer[12] = 0x08;
+ sc->sense_buffer[13] = 0x00;
+ sc->result = (DID_NO_CONNECT << 16);
+ sc->resid = sc->request_bufflen;
+ sc->scsi_done(sc);
+ return 0;
+}
+
+static int
+iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
+{
+ int i;
+
+ *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
+ if (*items == NULL)
+ return -ENOMEM;
+
+ q->max = max;
+ q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
+ if (q->pool == NULL) {
+ kfree(*items);
+ return -ENOMEM;
+ }
+
+ q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
+ GFP_KERNEL, NULL);
+ if (q->queue == ERR_PTR(-ENOMEM)) {
+ kfree(q->pool);
+ kfree(*items);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < max; i++) {
+ q->pool[i] = kmalloc(item_size, GFP_KERNEL);
+ if (q->pool[i] == NULL) {
+ int j;
+ for (j = 0; j < i; j++) {
+ kfree(q->pool[j]);
+ }
+ kfifo_free(q->queue);
+ kfree(q->pool);
+ kfree(*items);
+ return -ENOMEM;
+ }
+ memset(q->pool[i], 0, item_size);
+ (*items)[i] = q->pool[i];
+ __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
+ }
+ return 0;
+}
+
+static void
+iscsi_pool_free(struct iscsi_queue *q, void **items)
+{
+ int i;
+
+ for (i = 0; i < q->max; i++)
+ kfree(items[i]);
+ kfree(q->pool);
+ kfree(items);
+}
+
+/*
+ * Allocate a new connection within the session and bind it to
+ * the given socket.
+ */
+static iscsi_cnx_t
+iscsi_conn_create(iscsi_snx_t snxh, uint32_t conn_idx)
+{
+ struct iscsi_session *session = iscsi_ptr(snxh);
+ struct iscsi_conn *conn = NULL;
+
+ conn = kmalloc(sizeof(struct iscsi_conn), GFP_KERNEL);
+ if (conn == NULL)
+ goto conn_alloc_fail;
+ memset(conn, 0, sizeof(struct iscsi_conn));
+
+ conn->c_stage = ISCSI_CNX_INITIAL_STAGE;
+ conn->in_progress = IN_PROGRESS_WAIT_HEADER;
+ conn->id = conn_idx;
+ conn->exp_statsn = 0;
+ conn->tmabort_state = TMABORT_INITIAL;
+
+ /* initial operational parameters */
+ conn->hdr_size = sizeof(struct iscsi_hdr);
+ conn->data_size = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
+ conn->max_recv_dlength = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
+
+ spin_lock_init(&conn->lock);
+
+ /* initialize general xmit PDU commands queue */
+ conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*),
+ GFP_KERNEL, NULL);
+ if (conn->xmitqueue == ERR_PTR(-ENOMEM))
+ goto xmitqueue_alloc_fail;
+
+ /* initialize write response PDU commands queue */
+ conn->writequeue = kfifo_alloc(session->cmds_max * sizeof(void*),
+ GFP_KERNEL, NULL);
+ if (conn->writequeue == ERR_PTR(-ENOMEM))
+ goto writequeue_alloc_fail;
+
+ /* initialize general immediate & non-immediate PDU commands queue */
+ conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
+ GFP_KERNEL, NULL);
+ if (conn->immqueue == ERR_PTR(-ENOMEM))
+ goto immqueue_alloc_fail;
+
+ conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
+ GFP_KERNEL, NULL);
+ if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
+ goto mgmtqueue_alloc_fail;
+
+ INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
+
+ /* allocate login_mtask used for the login/text sequences */
+ spin_lock_bh(&session->lock);
+ if (!__kfifo_get(session->mgmtpool.queue,
+ (void*)&conn->login_mtask,
+ sizeof(void*))) {
+ spin_unlock_bh(&session->lock);
+ goto login_mtask_alloc_fail;
+ }
+ spin_unlock_bh(&session->lock);
+
+ /* allocate initial PDU receive place holder */
+ if (conn->data_size <= PAGE_SIZE)
+ conn->data = kmalloc(conn->data_size, GFP_KERNEL);
+ else
+ conn->data = (void*)__get_free_pages(GFP_KERNEL,
+ get_order(conn->data_size));
+ if (!conn->data)
+ goto max_recv_dlenght_alloc_fail;
+
+ init_timer(&conn->tmabort_timer);
+ init_MUTEX(&conn->xmitsema);
+ init_waitqueue_head(&conn->ehwait);
+
+ return iscsi_handle(conn);
+
+max_recv_dlenght_alloc_fail:
+ spin_lock_bh(&session->lock);
+ __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
+ sizeof(void*));
+ spin_unlock_bh(&session->lock);
+login_mtask_alloc_fail:
+ kfifo_free(conn->mgmtqueue);
+mgmtqueue_alloc_fail:
+ kfifo_free(conn->immqueue);
+immqueue_alloc_fail:
+ kfifo_free(conn->writequeue);
+writequeue_alloc_fail:
+ kfifo_free(conn->xmitqueue);
+xmitqueue_alloc_fail:
+ kfree(conn);
+conn_alloc_fail:
+ return iscsi_handle(NULL);
+}
+
+/*
+ * Terminate connection queues, free all associated resources.
+ */
+static void
+iscsi_conn_destroy(iscsi_cnx_t cnxh)
+{
+ struct iscsi_conn *conn = iscsi_ptr(cnxh);
+ struct iscsi_session *session = conn->session;
+
+ if (conn->c_stage == ISCSI_CNX_INITIAL_STAGE) {
+ /*
+ * conn_start() was never been called!
+ * we must cleanup socket.
+ */
+ sock_hold(conn->sock->sk);
+ iscsi_conn_restore_callbacks(conn);
+ sock_put(conn->sock->sk);
+ sock_release(conn->sock);
+ }
+
+ del_timer_sync(&conn->tmabort_timer);
+ if (session->leadconn == conn) {
+ /*
+ * Control plane decided to destroy leading connection?
+ * Its a signal for us to give up on recovery.
+ */
+ session->state = ISCSI_STATE_TERMINATE;
+ wake_up(&conn->ehwait);
+ }
+
+ /*
+ * Block control plane caller (a thread coming from
+ * a user space) until all the in-progress commands for this connection
+ * time out or fail.
+ * We must serialize with xmitwork recv pathes.
+ */
+ down(&conn->xmitsema);
+ conn->c_stage = ISCSI_CNX_CLEANUP_WAIT;
+ for (;;) {
+ spin_lock_bh(&conn->lock);
+ if (!session->host->host_busy) { /* OK for ERL == 0 */
+ spin_unlock_bh(&conn->lock);
+ break;
+ }
+ spin_unlock_bh(&conn->lock);
+ msleep_interruptible(500);
+ debug_scsi("destroy_cnx(): host_busy %d host_failed %d\n",
+ session->host->host_busy,
+ session->host->host_failed);
+ }
+ up(&conn->xmitsema);
+
+ /* now free crypto */
+ if (conn->hdrdgst_en || conn->datadgst_en) {
+ if (conn->tx_tfm)
+ crypto_free_tfm(conn->tx_tfm);
+ if (conn->rx_tfm)
+ crypto_free_tfm(conn->rx_tfm);
+ }
+
+ /* free conn->data, size = MaxRecvDataSegmentLength */
+ if (conn->data_size <= PAGE_SIZE)
+ kfree(conn->data);
+ else
+ free_pages((unsigned long)conn->data,
+ get_order(conn->data_size));
+
+ spin_lock_bh(&session->lock);
+ __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
+ sizeof(void*));
+ spin_unlock_bh(&session->lock);
+
+ kfifo_free(conn->xmitqueue);
+ kfifo_free(conn->writequeue);
+ kfifo_free(conn->immqueue);
+ kfifo_free(conn->mgmtqueue);
+
+ spin_lock_bh(&session->conn_lock);
+ list_del(&conn->item);
+ if (list_empty(&session->connections))
+ session->leadconn = NULL;
+ if (session->leadconn && session->leadconn == conn)
+ session->leadconn = container_of(session->connections.next,
+ struct iscsi_conn, item);
+ spin_unlock_bh(&session->conn_lock);
+
+ if (session->leadconn == NULL)
+ /* non connections exits.. reset sequencing */
+ session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
+
+ kfree(conn);
+}
+
+static int
+iscsi_conn_bind(iscsi_snx_t snxh, iscsi_cnx_t cnxh, uint32_t transport_fd,
+ int is_leading)
+{
+ struct iscsi_session *session = iscsi_ptr(snxh);
+ struct iscsi_conn *cnx = ERR_PTR(-EEXIST), *conn = iscsi_ptr(cnxh);
+ struct sock *sk;
+ struct socket *sock;
+ int err;
+
+ /* lookup for existing socket */
+ if (!(sock = sockfd_lookup(transport_fd, &err))) {
+ printk("iscsi_tcp: sockfd_lookup failed %d\n", err);
+ return -EEXIST;
+ }
+
+ /* lookup for existing connection */
+ spin_lock_bh(&session->conn_lock);
+ list_for_each_entry(cnx, &session->connections, item) {
+ if (cnx == conn) {
+ if (conn->c_stage != ISCSI_CNX_STOPPED ||
+ conn->stop_stage == STOP_CNX_TERM) {
+ printk("iscsi_tcp: can't bind non-stopped "
+ "connection (%d:%d)\n", conn->c_stage,
+ conn->stop_stage);
+ spin_unlock_bh(&session->conn_lock);
+ return -EIO;
+ }
+ break;
+ }
+ }
+ spin_unlock_bh(&session->conn_lock);
+ if (cnx != conn) {
+ /* bind new iSCSI connection to session */
+ conn->session = session;
+
+ spin_lock_bh(&session->conn_lock);
+ list_add(&conn->item, &session->connections);
+ spin_unlock_bh(&session->conn_lock);
+ }
+
+ if (conn->stop_stage != STOP_CNX_SUSPEND) {
+ /* bind iSCSI connection and socket */
+ conn->sock = sock;
+
+ /* setup Socket parameters */
+ sk = sock->sk;
+ sk->sk_reuse = 1;
+ sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
+ sk->sk_allocation = GFP_ATOMIC;
+
+ /* FIXME: disable Nagle's algorithm */
+
+ /*
+ * Intercept TCP callbacks for sendfile like receive
+ * processing.
+ */
+ iscsi_conn_set_callbacks(conn);
+ }
+
+ if (is_leading)
+ session->leadconn = conn;
+
+ /*
+ * Unblock xmitworker().
+ * Login Phase will pass through.
+ */
+ conn->suspend = 0;
+
+ return 0;
+}
+
+static int
+iscsi_conn_start(iscsi_cnx_t cnxh)
+{
+ struct iscsi_conn *conn = iscsi_ptr(cnxh);
+ struct iscsi_session *session = conn->session;
+
+ /* FF phase warming up... */
+
+ if (session == NULL) {
+ printk("iscsi_tcp: can't start not-binded connection\n");
+ return -EPERM;
+ }
+
+ spin_lock_bh(&session->lock);
+ conn->c_stage = ISCSI_CNX_STARTED;
+ conn->cpu = session->conn_cnt % num_online_cpus();
+ session->state = ISCSI_STATE_LOGGED_IN;
+ session->conn_cnt++;
+
+ if (conn->stop_stage == STOP_CNX_RECOVER) {
+ /*
+ * unblock eh_abort() if it is blocked. re-try all
+ * commands after successful recovery
+ */
+ conn->stop_stage = 0;
+ session->generation++;
+ wake_up(&conn->ehwait);
+ } else
+ conn->stop_stage = 0;
+ spin_unlock_bh(&session->lock);
+
+ return 0;
+}
+
+static void
+iscsi_conn_stop(iscsi_cnx_t cnxh, int flag)
+{
+ struct iscsi_conn *conn = iscsi_ptr(cnxh);
+ struct iscsi_session *session = conn->session;
+
+ conn->stop_stage = flag;
+
+ spin_lock_bh(&session->lock);
+ conn->c_stage = ISCSI_CNX_STOPPED;
+ session->conn_cnt--;
+ conn->suspend = 1;
+
+ if (session->conn_cnt == 0 || session->leadconn == conn)
+ session->state = ISCSI_STATE_FAILED;
+
+ spin_unlock_bh(&session->lock);
+
+ if (flag == STOP_CNX_TERM || flag == STOP_CNX_RECOVER) {
+ BUG_ON(!conn->sock);
+
+ /*
+ * Socket must go now.
+ */
+ sock_hold(conn->sock->sk);
+ iscsi_conn_restore_callbacks(conn);
+ sock_put(conn->sock->sk);
+
+ /*
+ * flush xmit queues.
+ */
+ down(&conn->xmitsema);
+ spin_lock_bh(&session->lock);
+ while (__kfifo_get(conn->writequeue, (void*)&conn->ctask,
+ sizeof(void*)) ||
+ __kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
+ sizeof(void*))) {
+ __kfifo_put(session->cmdpool.queue, (void*)&conn->ctask,
+ sizeof(void*));
+ }
+ conn->ctask = NULL;
+ while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
+ sizeof(void*)) ||
+ __kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
+ sizeof(void*))) {
+ __kfifo_put(session->mgmtpool.queue,
+ (void*)&conn->mtask, sizeof(void*));
+ }
+ spin_unlock_bh(&session->lock);
+ conn->mtask = NULL;
+ up(&conn->xmitsema);
+
+ /*
+ * release socket only after we stopped data_xmit()
+ * activity and flushed all outstandings
+ */
+ sock_release(conn->sock);
+
+ /*
+ * for connection level recovery we should not calculate
+ * header digest. conn->hdr_size used for optimization
+ * in hdr_extract() and will be re-negotiated at
+ * set_param() time.
+ */
+ if (flag == STOP_CNX_RECOVER)
+ conn->hdr_size = sizeof(struct iscsi_hdr);
+ }
+}
+
+static int
+iscsi_conn_send_pdu(iscsi_cnx_t cnxh, struct iscsi_hdr *hdr, char *data,
+ uint32_t data_size)
+{
+ struct iscsi_conn *conn = iscsi_ptr(cnxh);
+ struct iscsi_session *session = conn->session;
+ struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
+ struct iscsi_mgmt_task *mtask;
+
+ spin_lock_bh(&session->lock);
+ if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
+ hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE)) {
+ /*
+ * Login and Text are sent serially, in
+ * request-followed-by-response sequence.
+ * Same mtask can be used. Same ITT must be used.
+ * Note that login_mtask is preallocated at cnx_create().
+ */
+ mtask = conn->login_mtask;
+ } else {
+ BUG_ON(conn->c_stage == ISCSI_CNX_INITIAL_STAGE);
+ BUG_ON(conn->c_stage == ISCSI_CNX_STOPPED);
+
+ if (!__kfifo_get(session->mgmtpool.queue,
+ (void*)&mtask, sizeof(void*))) {
+ spin_unlock_bh(&session->lock);
+ return -ENOSPC;
+ }
+ }
+
+ /*
+ * pre-format CmdSN and ExpStatSN for outgoing PDU.
+ */
+ if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
+ hdr->itt = cpu_to_be32(mtask->itt);
+ nop->cmdsn = cpu_to_be32(session->cmdsn);
+ if (conn->c_stage == ISCSI_CNX_STARTED)
+ session->cmdsn++;
+ } else {
+ /* do not advance CmdSN */
+ nop->cmdsn = cpu_to_be32(session->cmdsn);
+ }
+
+ nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
+
+ memcpy(&mtask->hdr, hdr, sizeof(struct iscsi_hdr));
+
+ if (conn->c_stage == ISCSI_CNX_INITIAL_STAGE ||
+ conn->stop_stage == STOP_CNX_RECOVER) {
+ iscsi_buf_init_virt(&mtask->headbuf, (char*)&mtask->hdr,
+ sizeof(struct iscsi_hdr));
+ } else {
+ /* this will update header digest */
+ iscsi_buf_init_hdr(conn, &mtask->headbuf, (char*)&mtask->hdr,
+ (u8 *)mtask->hdrext);
+ }
+ spin_unlock_bh(&session->lock);
+
+ if (data_size) {
+ memcpy(mtask->data, data, data_size);
+ mtask->data_count = data_size;
+ } else
+ mtask->data_count = 0;
+
+ mtask->xmstate = XMSTATE_IMM_HDR;
+
+ if (mtask->data_count) {
+ iscsi_buf_init_virt(&mtask->sendbuf, (char*)mtask->data,
+ mtask->data_count);
+ /* FIXME: implement: convertion of mtask->data into 1st
+ * mtask->sendbuf. Keep in mind that virtual buffer
+ * could be spreaded across multiple pages... */
+ if(mtask->sendbuf.sg.offset + mtask->data_count > PAGE_SIZE) {
+ if (conn->c_stage == ISCSI_CNX_STARTED) {
+ spin_lock_bh(&session->lock);
+ __kfifo_put(session->mgmtpool.queue,
+ (void*)&mtask, sizeof(void*));
+ spin_unlock_bh(&session->lock);
+ }
+ return -ENOMEM;
+ }
+ }
+
+ debug_scsi("mgmtpdu [op 0x%x itt 0x%x datalen %d]\n",
+ hdr->opcode, be32_to_cpu(hdr->itt), data_size);
+
+ if (hdr->opcode & ISCSI_OP_IMMEDIATE)
+ __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
+ else
+ __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
+
+ schedule_work(&conn->xmitwork);
+
+ return 0;
+}
+
+static void
+iscsi_tmabort_timedout(unsigned long data)
+{
+ struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
+ struct iscsi_conn *conn = ctask->conn;
+
+ conn->tmabort_state = TMABORT_TIMEDOUT;
+ debug_scsi("tmabort timedout [sc %lx itt 0x%x]\n", (long)ctask->sc,
+ ctask->itt);
+
+ /* unblock eh_abort() */
+ wake_up(&conn->ehwait);
+}
+
+static int
+iscsi_eh_abort(struct scsi_cmnd *sc)
+{
+ int rc;
+ struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
+ struct iscsi_conn *conn = ctask->conn;
+ struct iscsi_session *session = conn->session;
+
+ spin_unlock_irq(session->host->host_lock);
+
+ debug_scsi("aborting [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
+
+ /*
+ * two cases for ERL=0 here:
+ *
+ * 1) connection-level failure;
+ * 2) recovery due protocol error;
+ */
+ if (session->state != ISCSI_STATE_LOGGED_IN) {
+ if (session->state == ISCSI_STATE_TERMINATE)
+ goto failed;
+ } else {
+ struct iscsi_tm *hdr = &conn->tmhdr;
+
+ /*
+ * Still LOGGED_IN...
+ */
+
+ spin_lock_bh(&session->lock);
+ if (sc->SCp.Status == SUCCESS ||
+ sc->SCp.phase != session->generation) {
+ /*
+ * 1) ctask completed before time out. But session
+ * is still ok => Happy Retry.
+ * 2) session was re-open during time out of ctask.
+ */
+ spin_unlock_bh(&session->lock);
+ goto success;
+ }
+ spin_unlock_bh(&session->lock);
+
+ /*
+ * ctask timed out but session is OK
+ * ERL=0 requires task mgmt abort to be issued on each
+ * failed command. requests must be serialized.
+ */
+ memset(hdr, 0, sizeof(struct iscsi_tm));
+ hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
+ hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
+ hdr->flags |= ISCSI_FLAG_CMD_FINAL;
+ memcpy(hdr->lun, ctask->hdr.lun, 8);
+ hdr->rtt = ctask->hdr.itt;
+ hdr->refcmdsn = ctask->hdr.cmdsn;
+
+ conn->tmabort_state = TMABORT_INITIAL;
+
+ rc = iscsi_conn_send_pdu(iscsi_handle(conn),
+ (struct iscsi_hdr *)hdr, NULL, 0);
+ if (rc) {
+ session->state = ISCSI_STATE_FAILED;
+ iscsi_cnx_error(iscsi_handle(conn),
+ ISCSI_ERR_CNX_FAILED);
+ debug_scsi("abort sent failure [itt 0x%x]", ctask->itt);
+ } else {
+ conn->tmfcmd_pdus_cnt++;
+ conn->tmabort_timer.expires = 3*HZ + jiffies; /*3 secs*/
+ conn->tmabort_timer.function = iscsi_tmabort_timedout;
+ conn->tmabort_timer.data = (unsigned long)ctask;
+ add_timer(&conn->tmabort_timer);
+ debug_scsi("abort sent [itt 0x%x]", ctask->itt);
+ }
+ }
+
+
+ /*
+ * block eh thread until:
+ *
+ * 1) abort response;
+ * 2) abort timeout;
+ * 3) session re-opened;
+ * 4) session terminated;
+ */
+ for (;;) {
+ int p_state = session->state;
+ rc = wait_event_interruptible(conn->ehwait,
+ (p_state == ISCSI_STATE_LOGGED_IN ?
+ (session->state == ISCSI_STATE_TERMINATE ||
+ conn->tmabort_state != TMABORT_INITIAL) :
+ (session->state == ISCSI_STATE_TERMINATE ||
+ session->state == ISCSI_STATE_LOGGED_IN)));
+ if (rc) {
+ /* shutdown.. */
+ session->state = ISCSI_STATE_TERMINATE;
+ goto failed;
+ }
+
+ if (signal_pending(current))
+ flush_signals(current);
+
+ if (session->state == ISCSI_STATE_TERMINATE)
+ goto failed;
+
+ if (conn->tmabort_state == TMABORT_TIMEDOUT ||
+ conn->tmabort_state == TMABORT_FAILED) {
+ conn->tmabort_state = TMABORT_INITIAL;
+ spin_lock_bh(&session->lock);
+ if (sc->SCp.Status == SUCCESS) {
+ /*
+ * ctask completed before tmf abort response or
+ * time out.
+ * But session is still ok => Happy Retry.
+ */
+ spin_unlock_bh(&session->lock);
+ break;
+ }
+ spin_unlock_bh(&session->lock);
+ session->state = ISCSI_STATE_FAILED;
+ iscsi_cnx_error(iscsi_handle(conn),
+ ISCSI_ERR_CNX_FAILED);
+ continue;
+ }
+
+ break;
+ }
+
+success:
+ debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
+ BUG_ON(session->state != ISCSI_STATE_LOGGED_IN);
+ spin_lock_irq(session->host->host_lock);
+ return SUCCESS;
+failed:
+ iscsi_ctask_cleanup(conn, ctask);
+ debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
+ spin_lock_irq(session->host->host_lock);
+ return FAILED;
+}
+
+static int
+iscsi_r2tpool_alloc(struct iscsi_session *session)
+{
+ int i;
+ int cmd_i;
+
+ /*
+ * initialize per-task: R2T pool and xmit queue
+ */
+ for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
+ struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
+
+ /*
+ * pre-allocated twice as much r2ts to handle race when
+ * target acks DataOut faster than we data_xmit() queues
+ * could replenish r2tqueue.
+ */
+
+ /* R2T pool */
+ if (iscsi_pool_init(&ctask->r2tpool, session->max_r2t * 2,
+ (void***)&ctask->r2ts, sizeof(struct iscsi_r2t_info))) {
+ goto r2t_alloc_fail;
+ }
+
+ /* R2T xmit queue */
+ ctask->r2tqueue = kfifo_alloc(
+ session->max_r2t * 2 * sizeof(void*), GFP_KERNEL, NULL);
+ if (ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
+ iscsi_pool_free(&ctask->r2tpool, (void**)ctask->r2ts);
+ goto r2t_alloc_fail;
+ }
+
+ /*
+ * number of
+ * Data-Out PDU's within R2T-sequence can be quite big;
+ * using mempool
+ */
+ ctask->datapool = mempool_create(ISCSI_DTASK_DEFAULT_MAX,
+ mempool_alloc_slab, mempool_free_slab, taskcache);
+ if (ctask->datapool == NULL) {
+ kfifo_free(ctask->r2tqueue);
+ iscsi_pool_free(&ctask->r2tpool, (void**)ctask->r2ts);
+ goto r2t_alloc_fail;
+ }
+ INIT_LIST_HEAD(&ctask->dataqueue);
+ }
+
+ return 0;
+
+r2t_alloc_fail:
+ for (i = 0; i < cmd_i; i++) {
+ mempool_destroy(session->cmds[i]->datapool);
+ kfifo_free(session->cmds[i]->r2tqueue);
+ iscsi_pool_free(&session->cmds[i]->r2tpool,
+ (void**)session->cmds[i]->r2ts);
+ }
+ return -ENOMEM;
+}
+
+static void
+iscsi_r2tpool_free(struct iscsi_session *session)
+{
+ int i;
+
+ for (i = 0; i < session->cmds_max; i++) {
+ mempool_destroy(session->cmds[i]->datapool);
+ kfifo_free(session->cmds[i]->r2tqueue);
+ iscsi_pool_free(&session->cmds[i]->r2tpool,
+ (void**)session->cmds[i]->r2ts);
+ }
+}
+
+static struct scsi_host_template iscsi_sht = {
+ .name = "iSCSI Initiator over TCP/IP, v."
+ ISCSI_VERSION_STR,
+ .queuecommand = iscsi_queuecommand,
+ .can_queue = ISCSI_XMIT_CMDS_MAX - 1,
+ .sg_tablesize = ISCSI_SG_TABLESIZE,
+ .cmd_per_lun = ISCSI_CMD_PER_LUN,
+ .eh_abort_handler = iscsi_eh_abort,
+ .use_clustering = DISABLE_CLUSTERING,
+ .proc_name = "iscsi_tcp",
+ .this_id = -1,
+};
+
+static iscsi_snx_t
+iscsi_session_create(uint32_t initial_cmdsn, struct Scsi_Host *host)
+{
+ int cmd_i;
+ struct iscsi_session *session;
+
+ session = iscsi_hostdata(host->hostdata);
+ memset(session, 0, sizeof(struct iscsi_session));
+
+ session->host = host;
+ session->id = host->host_no;
+ session->state = ISCSI_STATE_LOGGED_IN;
+ session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
+ session->cmds_max = ISCSI_XMIT_CMDS_MAX;
+ session->cmdsn = initial_cmdsn;
+ session->exp_cmdsn = initial_cmdsn + 1;
+ session->max_cmdsn = initial_cmdsn + 1;
+ session->max_r2t = 1;
+
+ /* initialize SCSI PDU commands pool */
+ if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
+ (void***)&session->cmds, sizeof(struct iscsi_cmd_task)))
+ goto cmdpool_alloc_fail;
+
+ /* pre-format cmds pool with ITT */
+ for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
+ session->cmds[cmd_i]->itt = cmd_i;
+ }
+
+ spin_lock_init(&session->lock);
+ spin_lock_init(&session->conn_lock);
+ INIT_LIST_HEAD(&session->connections);
+
+ /* initialize immediate command pool */
+ if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
+ (void***)&session->mgmt_cmds, sizeof(struct iscsi_mgmt_task)))
+ goto mgmtpool_alloc_fail;
+
+
+ /* pre-format immediate cmds pool with ITT */
+ for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
+ session->mgmt_cmds[cmd_i]->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
+ session->mgmt_cmds[cmd_i]->data = kmalloc(
+ DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
+ if (!session->mgmt_cmds[cmd_i]->data) {
+ int j;
+ for (j = 0; j < cmd_i; j++)
+ kfree(session->mgmt_cmds[j]->data);
+ goto immdata_alloc_fail;
+ }
+ }
+
+ if (iscsi_r2tpool_alloc(session))
+ goto r2tpool_alloc_fail;
+
+ if (!try_module_get(THIS_MODULE)) {
+ printk("iscsi_tcp: can not reserve module\n");
+ goto module_get_fault;
+ }
+
+ return iscsi_handle(session);
+
+module_get_fault:
+ iscsi_r2tpool_free(session);
+r2tpool_alloc_fail:
+ for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
+ kfree(session->mgmt_cmds[cmd_i]->data);
+ iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
+immdata_alloc_fail:
+mgmtpool_alloc_fail:
+ iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
+cmdpool_alloc_fail:
+ return iscsi_handle(NULL);
+}
+
+static void
+iscsi_session_destroy(iscsi_snx_t snxh)
+{
+ int cmd_i;
+ struct iscsi_data_task *dtask, *n;
+ struct iscsi_session *session = iscsi_ptr(snxh);
+
+ for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
+ struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
+ list_for_each_entry_safe(dtask, n, &ctask->dataqueue, item) {
+ list_del(&dtask->item);
+ mempool_free(dtask, ctask->datapool);
+ }
+ }
+
+ for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
+ kfree(session->mgmt_cmds[cmd_i]->data);
+
+ iscsi_r2tpool_free(session);
+ iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
+ iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
+ module_put(THIS_MODULE);
+}
+
+static int
+iscsi_conn_set_param(iscsi_cnx_t cnxh, enum iscsi_param param, uint32_t value)
+{
+ struct iscsi_conn *conn = iscsi_ptr(cnxh);
+ struct iscsi_session *session = conn->session;
+
+ if (conn->c_stage == ISCSI_CNX_INITIAL_STAGE ||
+ conn->stop_stage == STOP_CNX_RECOVER) {
+ switch(param) {
+ case ISCSI_PARAM_MAX_RECV_DLENGTH: {
+ char *saveptr = conn->data;
+ int flags = GFP_KERNEL;
+
+ if (conn->data_size >= value) {
+ conn->max_recv_dlength = value;
+ break;
+ }
+
+ if (conn->stop_stage == STOP_CNX_RECOVER)
+ flags = GFP_ATOMIC;
+
+ if (value <= PAGE_SIZE)
+ conn->data = kmalloc(value, flags);
+ else
+ conn->data = (void*)__get_free_pages(flags,
+ get_order(value));
+ if (conn->data == NULL) {
+ conn->data = saveptr;
+ return -ENOMEM;
+ }
+ if (conn->data_size <= PAGE_SIZE)
+ kfree(saveptr);
+ else
+ free_pages((unsigned long)saveptr,
+ get_order(conn->data_size));
+ conn->max_recv_dlength = value;
+ conn->data_size = value;
+ }
+ break;
+ case ISCSI_PARAM_MAX_XMIT_DLENGTH:
+ conn->max_xmit_dlength = value;
+ break;
+ case ISCSI_PARAM_HDRDGST_EN:
+ conn->hdrdgst_en = value;
+ conn->hdr_size = sizeof(struct iscsi_hdr);
+ if (conn->hdrdgst_en) {
+ conn->hdr_size += sizeof(__u32);
+ if (!conn->tx_tfm)
+ conn->tx_tfm =
+ crypto_alloc_tfm("crc32c", 0);
+ if (!conn->tx_tfm)
+ return -ENOMEM;
+ if (!conn->rx_tfm)
+ conn->rx_tfm =
+ crypto_alloc_tfm("crc32c", 0);
+ if (!conn->rx_tfm) {
+ crypto_free_tfm(conn->tx_tfm);
+ return -ENOMEM;
+ }
+ } else {
+ if (conn->tx_tfm)
+ crypto_free_tfm(conn->tx_tfm);
+ if (conn->rx_tfm)
+ crypto_free_tfm(conn->rx_tfm);
+ }
+ break;
+ case ISCSI_PARAM_DATADGST_EN:
+ if (conn->datadgst_en)
+ return -EPERM;
+ conn->datadgst_en = value;
+ break;
+ case ISCSI_PARAM_INITIAL_R2T_EN:
+ session->initial_r2t_en = value;
+ break;
+ case ISCSI_PARAM_MAX_R2T:
+ if (session->max_r2t == roundup_pow_of_two(value))
+ break;
+ iscsi_r2tpool_free(session);
+ session->max_r2t = value;
+ if (session->max_r2t & (session->max_r2t - 1)) {
+ session->max_r2t =
+ roundup_pow_of_two(session->max_r2t);
+ }
+ if (iscsi_r2tpool_alloc(session))
+ return -ENOMEM;
+ break;
+ case ISCSI_PARAM_IMM_DATA_EN:
+ session->imm_data_en = value;
+ break;
+ case ISCSI_PARAM_FIRST_BURST:
+ session->first_burst = value;
+ break;
+ case ISCSI_PARAM_MAX_BURST:
+ session->max_burst = value;
+ break;
+ case ISCSI_PARAM_PDU_INORDER_EN:
+ session->pdu_inorder_en = value;
+ break;
+ case ISCSI_PARAM_DATASEQ_INORDER_EN:
+ session->dataseq_inorder_en = value;
+ break;
+ case ISCSI_PARAM_ERL:
+ session->erl = value;
+ break;
+ case ISCSI_PARAM_IFMARKER_EN:
+ session->ifmarker_en = value;
+ break;
+ case ISCSI_PARAM_OFMARKER_EN:
+ session->ifmarker_en = value;
+ break;
+ default:
+ break;
+ }
+ } else {
+ printk("iscsi_tcp: can not change parameter [%d]\n", param);
+ }
+
+ return 0;
+}
+
+static int
+iscsi_conn_get_param(iscsi_cnx_t cnxh, enum iscsi_param param, uint32_t *value)
+{
+ struct iscsi_conn *conn = iscsi_ptr(cnxh);
+ struct iscsi_session *session = conn->session;
+
+ switch(param) {
+ case ISCSI_PARAM_MAX_RECV_DLENGTH:
+ *value = conn->max_recv_dlength;
+ break;
+ case ISCSI_PARAM_MAX_XMIT_DLENGTH:
+ *value = conn->max_xmit_dlength;
+ break;
+ case ISCSI_PARAM_HDRDGST_EN:
+ *value = conn->hdrdgst_en;
+ break;
+ case ISCSI_PARAM_DATADGST_EN:
+ *value = conn->datadgst_en;
+ break;
+ case ISCSI_PARAM_INITIAL_R2T_EN:
+ *value = session->initial_r2t_en;
+ break;
+ case ISCSI_PARAM_MAX_R2T:
+ *value = session->max_r2t;
+ break;
+ case ISCSI_PARAM_IMM_DATA_EN:
+ *value = session->imm_data_en;
+ break;
+ case ISCSI_PARAM_FIRST_BURST:
+ *value = session->first_burst;
+ break;
+ case ISCSI_PARAM_MAX_BURST:
+ *value = session->max_burst;
+ break;
+ case ISCSI_PARAM_PDU_INORDER_EN:
+ *value = session->pdu_inorder_en;
+ break;
+ case ISCSI_PARAM_DATASEQ_INORDER_EN:
+ *value = session->dataseq_inorder_en;
+ break;
+ case ISCSI_PARAM_ERL:
+ *value = session->erl;
+ break;
+ case ISCSI_PARAM_IFMARKER_EN:
+ *value = session->ifmarker_en;
+ break;
+ case ISCSI_PARAM_OFMARKER_EN:
+ *value = session->ifmarker_en;
+ break;
+ default:
+ return ISCSI_ERR_PARAM_NOT_FOUND;
+ }
+
+ return 0;
+}
+
+static void
+iscsi_conn_get_stats(iscsi_cnx_t cnxh, struct iscsi_stats *stats)
+{
+ struct iscsi_conn *conn = iscsi_ptr(cnxh);
+
+ stats->txdata_octets = conn->txdata_octets;
+ stats->rxdata_octets = conn->rxdata_octets;
+ stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
+ stats->dataout_pdus = conn->dataout_pdus_cnt;
+ stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
+ stats->datain_pdus = conn->datain_pdus_cnt;
+ stats->r2t_pdus = conn->r2t_pdus_cnt;
+ stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
+ stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
+ stats->custom_length = 2;
+ strcpy(stats->custom[0].desc, "tx_sendpage_failures");
+ stats->custom[0].value = conn->sendpage_failures_cnt;
+ strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
+ stats->custom[1].value = conn->discontiguous_hdr_cnt;
+}
+
+static struct iscsi_transport iscsi_tcp_transport = {
+ .owner = THIS_MODULE,
+ .name = "tcp",
+ .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST,
+ .host_template = &iscsi_sht,
+ .hostdata_size = sizeof(struct iscsi_session),
+ .max_lun = ISCSI_TCP_MAX_LUN,
+ .max_cmd_len = ISCSI_TCP_MAX_CMD_LEN,
+ .create_session = iscsi_session_create,
+ .destroy_session = iscsi_session_destroy,
+ .create_cnx = iscsi_conn_create,
+ .bind_cnx = iscsi_conn_bind,
+ .destroy_cnx = iscsi_conn_destroy,
+ .set_param = iscsi_conn_set_param,
+ .get_param = iscsi_conn_get_param,
+ .start_cnx = iscsi_conn_start,
+ .stop_cnx = iscsi_conn_stop,
+ .send_pdu = iscsi_conn_send_pdu,
+ .get_stats = iscsi_conn_get_stats,
+};
+
+static int __init
+iscsi_tcp_init(void)
+{
+ int error;
+
+ taskcache = kmem_cache_create("iscsi_taskcache",
+ sizeof(struct iscsi_data_task), 0,
+ SLAB_HWCACHE_ALIGN | SLAB_NO_REAP, NULL, NULL);
+ if (!taskcache)
+ return -ENOMEM;
+
+ error = iscsi_register_transport(&iscsi_tcp_transport);
+ if (error)
+ kmem_cache_destroy(taskcache);
+
+ return error;
+}
+
+static void __exit
+iscsi_tcp_exit(void)
+{
+ iscsi_unregister_transport(&iscsi_tcp_transport);
+ kmem_cache_destroy(taskcache);
+}
+
+module_init(iscsi_tcp_init);
+module_exit(iscsi_tcp_exit);