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-rw-r--r--drivers/scsi/libiscsi.c1702
1 files changed, 1702 insertions, 0 deletions
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
new file mode 100644
index 0000000..2673a11
--- /dev/null
+++ b/drivers/scsi/libiscsi.c
@@ -0,0 +1,1702 @@
+/*
+ * iSCSI lib functions
+ *
+ * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2004 - 2006 Mike Christie
+ * Copyright (C) 2004 - 2005 Dmitry Yusupov
+ * Copyright (C) 2004 - 2005 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+#include <linux/types.h>
+#include <linux/mutex.h>
+#include <linux/kfifo.h>
+#include <linux/delay.h>
+#include <net/tcp.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi.h>
+#include <scsi/iscsi_proto.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_iscsi.h>
+#include <scsi/libiscsi.h>
+
+struct iscsi_session *
+class_to_transport_session(struct iscsi_cls_session *cls_session)
+{
+ struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
+ return iscsi_hostdata(shost->hostdata);
+}
+EXPORT_SYMBOL_GPL(class_to_transport_session);
+
+#define INVALID_SN_DELTA 0xffff
+
+int
+iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
+{
+ uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
+ uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
+
+ if (max_cmdsn < exp_cmdsn -1 &&
+ max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
+ return ISCSI_ERR_MAX_CMDSN;
+ if (max_cmdsn > session->max_cmdsn ||
+ max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
+ session->max_cmdsn = max_cmdsn;
+ if (exp_cmdsn > session->exp_cmdsn ||
+ exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
+ session->exp_cmdsn = exp_cmdsn;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_check_assign_cmdsn);
+
+void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
+ struct iscsi_data *hdr,
+ int transport_data_cnt)
+{
+ struct iscsi_conn *conn = ctask->conn;
+
+ 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;
+ memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
+
+ hdr->itt = ctask->hdr->itt;
+ hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
+
+ hdr->offset = cpu_to_be32(ctask->total_length -
+ transport_data_cnt -
+ 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;
+ }
+}
+EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
+
+/**
+ * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
+ * @ctask: iscsi cmd task
+ *
+ * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
+ * fields like dlength or final based on how much data it sends
+ */
+static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
+{
+ struct iscsi_conn *conn = ctask->conn;
+ struct iscsi_session *session = conn->session;
+ struct iscsi_cmd *hdr = ctask->hdr;
+ struct scsi_cmnd *sc = ctask->sc;
+
+ hdr->opcode = ISCSI_OP_SCSI_CMD;
+ hdr->flags = ISCSI_ATTR_SIMPLE;
+ int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
+ hdr->itt = ctask->itt | (conn->id << ISCSI_CID_SHIFT) |
+ (session->age << ISCSI_AGE_SHIFT);
+ hdr->data_length = cpu_to_be32(sc->request_bufflen);
+ hdr->cmdsn = cpu_to_be32(session->cmdsn);
+ session->cmdsn++;
+ hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
+ memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
+ memset(&hdr->cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
+
+ if (sc->sc_data_direction == DMA_TO_DEVICE) {
+ hdr->flags |= ISCSI_FLAG_CMD_WRITE;
+ /*
+ * 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;
+
+ 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);
+ } 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->datasn = 0;
+ hdr->flags |= ISCSI_FLAG_CMD_FINAL;
+ zero_data(hdr->dlength);
+
+ if (sc->sc_data_direction == DMA_FROM_DEVICE)
+ hdr->flags |= ISCSI_FLAG_CMD_READ;
+ }
+
+ conn->scsicmd_pdus_cnt++;
+}
+EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
+
+/**
+ * iscsi_complete_command - return command back to scsi-ml
+ * @session: iscsi session
+ * @ctask: iscsi cmd task
+ *
+ * Must be called with session lock.
+ * This function returns the scsi command to scsi-ml and returns
+ * the cmd task to the pool of available cmd tasks.
+ */
+static void iscsi_complete_command(struct iscsi_session *session,
+ struct iscsi_cmd_task *ctask)
+{
+ struct scsi_cmnd *sc = ctask->sc;
+
+ ctask->sc = NULL;
+ list_del_init(&ctask->running);
+ __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
+ sc->scsi_done(sc);
+}
+
+/**
+ * iscsi_cmd_rsp - SCSI Command Response processing
+ * @conn: iscsi connection
+ * @hdr: iscsi header
+ * @ctask: scsi command task
+ * @data: cmd data buffer
+ * @datalen: len of buffer
+ *
+ * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
+ * then completes the command and task.
+ **/
+static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+ struct iscsi_cmd_task *ctask, char *data,
+ int datalen)
+{
+ int rc;
+ struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
+ struct iscsi_session *session = conn->session;
+ struct scsi_cmnd *sc = ctask->sc;
+
+ rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
+ if (rc) {
+ sc->result = DID_ERROR << 16;
+ goto out;
+ }
+
+ conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
+
+ sc->result = (DID_OK << 16) | rhdr->cmd_status;
+
+ if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
+ sc->result = DID_ERROR << 16;
+ goto out;
+ }
+
+ if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
+ int senselen;
+
+ if (datalen < 2) {
+invalid_datalen:
+ printk(KERN_ERR "iscsi: Got CHECK_CONDITION but "
+ "invalid data buffer size of %d\n", datalen);
+ sc->result = DID_BAD_TARGET << 16;
+ goto out;
+ }
+
+ senselen = (data[0] << 8) | data[1];
+ if (datalen < senselen)
+ goto invalid_datalen;
+
+ memcpy(sc->sense_buffer, data + 2,
+ min(senselen, SCSI_SENSE_BUFFERSIZE));
+ debug_scsi("copied %d bytes of sense\n",
+ min(senselen, SCSI_SENSE_BUFFERSIZE));
+ }
+
+ if (sc->sc_data_direction == DMA_TO_DEVICE)
+ goto out;
+
+ 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);
+
+out:
+ debug_scsi("done [sc %lx res %d itt 0x%x]\n",
+ (long)sc, sc->result, ctask->itt);
+ conn->scsirsp_pdus_cnt++;
+
+ iscsi_complete_command(conn->session, ctask);
+ return rc;
+}
+
+/**
+ * __iscsi_complete_pdu - complete pdu
+ * @conn: iscsi conn
+ * @hdr: iscsi header
+ * @data: data buffer
+ * @datalen: len of data buffer
+ *
+ * Completes pdu processing by freeing any resources allocated at
+ * queuecommand or send generic. session lock must be held and verify
+ * itt must have been called.
+ */
+int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+ char *data, int datalen)
+{
+ struct iscsi_session *session = conn->session;
+ int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
+ struct iscsi_cmd_task *ctask;
+ struct iscsi_mgmt_task *mtask;
+ uint32_t itt;
+
+ if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG))
+ itt = hdr->itt & ISCSI_ITT_MASK;
+ else
+ itt = hdr->itt;
+
+ if (itt < session->cmds_max) {
+ ctask = session->cmds[itt];
+
+ debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
+ opcode, conn->id, ctask->itt, datalen);
+
+ switch(opcode) {
+ case ISCSI_OP_SCSI_CMD_RSP:
+ BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
+ rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
+ datalen);
+ break;
+ case ISCSI_OP_SCSI_DATA_IN:
+ BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
+ if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
+ conn->scsirsp_pdus_cnt++;
+ iscsi_complete_command(session, ctask);
+ }
+ break;
+ case ISCSI_OP_R2T:
+ /* LLD handles this for now */
+ break;
+ default:
+ rc = ISCSI_ERR_BAD_OPCODE;
+ break;
+ }
+ } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
+ itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
+ mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
+
+ debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
+ opcode, conn->id, mtask->itt, datalen);
+
+ rc = iscsi_check_assign_cmdsn(session,
+ (struct iscsi_nopin*)hdr);
+ if (rc)
+ goto done;
+
+ switch(opcode) {
+ case ISCSI_OP_LOGOUT_RSP:
+ conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+ /* fall through */
+ case ISCSI_OP_LOGIN_RSP:
+ case ISCSI_OP_TEXT_RSP:
+ /*
+ * login related PDU's exp_statsn is handled in
+ * userspace
+ */
+ rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
+ list_del(&mtask->running);
+ if (conn->login_mtask != mtask)
+ __kfifo_put(session->mgmtpool.queue,
+ (void*)&mtask, sizeof(void*));
+ break;
+ case ISCSI_OP_SCSI_TMFUNC_RSP:
+ if (datalen) {
+ rc = ISCSI_ERR_PROTO;
+ break;
+ }
+
+ conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+ conn->tmfrsp_pdus_cnt++;
+ if (conn->tmabort_state == TMABORT_INITIAL) {
+ conn->tmabort_state =
+ ((struct iscsi_tm_rsp *)hdr)->
+ response == ISCSI_TMF_RSP_COMPLETE ?
+ TMABORT_SUCCESS:TMABORT_FAILED;
+ /* unblock eh_abort() */
+ wake_up(&conn->ehwait);
+ }
+ break;
+ case ISCSI_OP_NOOP_IN:
+ if (hdr->ttt != ISCSI_RESERVED_TAG) {
+ rc = ISCSI_ERR_PROTO;
+ break;
+ }
+ conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+
+ rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
+ list_del(&mtask->running);
+ if (conn->login_mtask != mtask)
+ __kfifo_put(session->mgmtpool.queue,
+ (void*)&mtask, sizeof(void*));
+ break;
+ default:
+ rc = ISCSI_ERR_BAD_OPCODE;
+ break;
+ }
+ } else if (itt == ISCSI_RESERVED_TAG) {
+ switch(opcode) {
+ case ISCSI_OP_NOOP_IN:
+ if (!datalen) {
+ rc = iscsi_check_assign_cmdsn(session,
+ (struct iscsi_nopin*)hdr);
+ if (!rc && hdr->ttt != ISCSI_RESERVED_TAG)
+ rc = iscsi_recv_pdu(conn->cls_conn,
+ hdr, NULL, 0);
+ } else
+ rc = ISCSI_ERR_PROTO;
+ break;
+ case ISCSI_OP_REJECT:
+ /* we need sth like iscsi_reject_rsp()*/
+ case ISCSI_OP_ASYNC_EVENT:
+ conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
+ /* we need sth like iscsi_async_event_rsp() */
+ rc = ISCSI_ERR_BAD_OPCODE;
+ break;
+ default:
+ rc = ISCSI_ERR_BAD_OPCODE;
+ break;
+ }
+ } else
+ rc = ISCSI_ERR_BAD_ITT;
+
+done:
+ return rc;
+}
+EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
+
+int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+ char *data, int datalen)
+{
+ int rc;
+
+ spin_lock(&conn->session->lock);
+ rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
+ spin_unlock(&conn->session->lock);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
+
+/* verify itt (itt encoding: age+cid+itt) */
+int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+ uint32_t *ret_itt)
+{
+ struct iscsi_session *session = conn->session;
+ struct iscsi_cmd_task *ctask;
+ uint32_t itt;
+
+ if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
+ if ((hdr->itt & ISCSI_AGE_MASK) !=
+ (session->age << ISCSI_AGE_SHIFT)) {
+ printk(KERN_ERR "iscsi: received itt %x expected "
+ "session age (%x)\n", hdr->itt,
+ session->age & ISCSI_AGE_MASK);
+ return ISCSI_ERR_BAD_ITT;
+ }
+
+ if ((hdr->itt & ISCSI_CID_MASK) !=
+ (conn->id << ISCSI_CID_SHIFT)) {
+ printk(KERN_ERR "iscsi: received itt %x, expected "
+ "CID (%x)\n", hdr->itt, conn->id);
+ return ISCSI_ERR_BAD_ITT;
+ }
+ itt = hdr->itt & ISCSI_ITT_MASK;
+ } else
+ itt = hdr->itt;
+
+ if (itt < session->cmds_max) {
+ ctask = session->cmds[itt];
+
+ if (!ctask->sc) {
+ printk(KERN_INFO "iscsi: dropping ctask with "
+ "itt 0x%x\n", ctask->itt);
+ /* force drop */
+ return ISCSI_ERR_NO_SCSI_CMD;
+ }
+
+ if (ctask->sc->SCp.phase != session->age) {
+ printk(KERN_ERR "iscsi: ctask's session age %d, "
+ "expected %d\n", ctask->sc->SCp.phase,
+ session->age);
+ return ISCSI_ERR_SESSION_FAILED;
+ }
+ }
+
+ *ret_itt = itt;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_verify_itt);
+
+void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
+{
+ struct iscsi_session *session = conn->session;
+ unsigned long flags;
+
+ spin_lock_irqsave(&session->lock, flags);
+ if (session->state == ISCSI_STATE_FAILED) {
+ spin_unlock_irqrestore(&session->lock, flags);
+ return;
+ }
+
+ if (conn->stop_stage == 0)
+ session->state = ISCSI_STATE_FAILED;
+ spin_unlock_irqrestore(&session->lock, flags);
+ set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+ set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
+ iscsi_conn_error(conn->cls_conn, err);
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_failure);
+
+/**
+ * iscsi_data_xmit - xmit any command into the scheduled connection
+ * @conn: iscsi connection
+ *
+ * Notes:
+ * 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)
+{
+ struct iscsi_transport *tt;
+ int rc = 0;
+
+ if (unlikely(conn->suspend_tx)) {
+ debug_scsi("conn %d Tx suspended!\n", conn->id);
+ return -ENODATA;
+ }
+ tt = conn->session->tt;
+
+ /*
+ * 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) {
+ rc = tt->xmit_cmd_task(conn, conn->ctask);
+ if (rc)
+ goto again;
+ /* done with this in-progress ctask */
+ conn->ctask = NULL;
+ }
+ if (conn->mtask) {
+ rc = tt->xmit_mgmt_task(conn, conn->mtask);
+ if (rc)
+ goto again;
+ /* done with this in-progress mtask */
+ conn->mtask = NULL;
+ }
+
+ /* process immediate first */
+ if (unlikely(__kfifo_len(conn->immqueue))) {
+ while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
+ sizeof(void*))) {
+ spin_lock_bh(&conn->session->lock);
+ list_add_tail(&conn->mtask->running,
+ &conn->mgmt_run_list);
+ spin_unlock_bh(&conn->session->lock);
+ rc = tt->xmit_mgmt_task(conn, conn->mtask);
+ if (rc)
+ goto again;
+ }
+ /* done with this mtask */
+ conn->mtask = NULL;
+ }
+
+ /* process command queue */
+ while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
+ sizeof(void*))) {
+ /*
+ * iscsi tcp may readd the task to the xmitqueue to send
+ * write data
+ */
+ spin_lock_bh(&conn->session->lock);
+ if (list_empty(&conn->ctask->running))
+ list_add_tail(&conn->ctask->running, &conn->run_list);
+ spin_unlock_bh(&conn->session->lock);
+ rc = tt->xmit_cmd_task(conn, conn->ctask);
+ if (rc)
+ goto again;
+ }
+ /* done with this ctask */
+ conn->ctask = NULL;
+
+ /* process the rest control plane PDUs, if any */
+ if (unlikely(__kfifo_len(conn->mgmtqueue))) {
+ while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
+ sizeof(void*))) {
+ spin_lock_bh(&conn->session->lock);
+ list_add_tail(&conn->mtask->running,
+ &conn->mgmt_run_list);
+ spin_unlock_bh(&conn->session->lock);
+ rc = tt->xmit_mgmt_task(conn, conn->mtask);
+ if (rc)
+ goto again;
+ }
+ /* done with this mtask */
+ conn->mtask = NULL;
+ }
+
+ return -ENODATA;
+
+again:
+ if (unlikely(conn->suspend_tx))
+ return -ENODATA;
+
+ return rc;
+}
+
+static void iscsi_xmitworker(void *data)
+{
+ struct iscsi_conn *conn = data;
+ int rc;
+ /*
+ * serialize Xmit worker on a per-connection basis.
+ */
+ mutex_lock(&conn->xmitmutex);
+ do {
+ rc = iscsi_data_xmit(conn);
+ } while (rc >= 0 || rc == -EAGAIN);
+ mutex_unlock(&conn->xmitmutex);
+}
+
+enum {
+ FAILURE_BAD_HOST = 1,
+ FAILURE_SESSION_FAILED,
+ FAILURE_SESSION_FREED,
+ FAILURE_WINDOW_CLOSED,
+ FAILURE_SESSION_TERMINATE,
+ FAILURE_SESSION_IN_RECOVERY,
+ FAILURE_SESSION_RECOVERY_TIMEOUT,
+};
+
+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;
+ struct iscsi_cmd_task *ctask = NULL;
+
+ sc->scsi_done = done;
+ sc->result = 0;
+
+ host = sc->device->host;
+ session = iscsi_hostdata(host->hostdata);
+
+ spin_lock(&session->lock);
+
+ /*
+ * ISCSI_STATE_FAILED is a temp. state. The recovery
+ * code will decide what is best to do with command queued
+ * during this time
+ */
+ if (session->state != ISCSI_STATE_LOGGED_IN &&
+ session->state != ISCSI_STATE_FAILED) {
+ /*
+ * to handle the race between when we set the recovery state
+ * and block the session we requeue here (commands could
+ * be entering our queuecommand while a block is starting
+ * up because the block code is not locked)
+ */
+ if (session->state == ISCSI_STATE_IN_RECOVERY) {
+ reason = FAILURE_SESSION_IN_RECOVERY;
+ goto reject;
+ }
+
+ if (session->state == ISCSI_STATE_RECOVERY_FAILED)
+ reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
+ else if (session->state == ISCSI_STATE_TERMINATE)
+ reason = FAILURE_SESSION_TERMINATE;
+ else
+ 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;
+
+ __kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
+ sc->SCp.phase = session->age;
+ sc->SCp.ptr = (char *)ctask;
+
+ ctask->mtask = NULL;
+ ctask->conn = conn;
+ ctask->sc = sc;
+ INIT_LIST_HEAD(&ctask->running);
+ ctask->total_length = sc->request_bufflen;
+ iscsi_prep_scsi_cmd_pdu(ctask);
+
+ session->tt->init_cmd_task(ctask);
+
+ __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);
+ spin_unlock(&session->lock);
+
+ scsi_queue_work(host, &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(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n",
+ sc->cmnd[0], reason);
+ sc->result = (DID_NO_CONNECT << 16);
+ sc->resid = sc->request_bufflen;
+ sc->scsi_done(sc);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_queuecommand);
+
+int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
+{
+ if (depth > ISCSI_MAX_CMD_PER_LUN)
+ depth = ISCSI_MAX_CMD_PER_LUN;
+ scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
+ return sdev->queue_depth;
+}
+EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
+
+static int
+iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+ char *data, uint32_t data_size)
+{
+ 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 (session->state == ISCSI_STATE_TERMINATE) {
+ spin_unlock_bh(&session->lock);
+ return -EPERM;
+ }
+ 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 conn_create().
+ */
+ mtask = conn->login_mtask;
+ else {
+ BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
+ BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
+
+ nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
+ if (!__kfifo_get(session->mgmtpool.queue,
+ (void*)&mtask, sizeof(void*))) {
+ spin_unlock_bh(&session->lock);
+ return -ENOSPC;
+ }
+ }
+
+ /*
+ * pre-format CmdSN for outgoing PDU.
+ */
+ if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
+ hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
+ (session->age << ISCSI_AGE_SHIFT);
+ nop->cmdsn = cpu_to_be32(session->cmdsn);
+ if (conn->c_stage == ISCSI_CONN_STARTED &&
+ !(hdr->opcode & ISCSI_OP_IMMEDIATE))
+ session->cmdsn++;
+ } else
+ /* do not advance CmdSN */
+ nop->cmdsn = cpu_to_be32(session->cmdsn);
+
+ if (data_size) {
+ memcpy(mtask->data, data, data_size);
+ mtask->data_count = data_size;
+ } else
+ mtask->data_count = 0;
+
+ INIT_LIST_HEAD(&mtask->running);
+ memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
+ if (session->tt->init_mgmt_task)
+ session->tt->init_mgmt_task(conn, mtask, data, data_size);
+ spin_unlock_bh(&session->lock);
+
+ debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
+ hdr->opcode, hdr->itt, data_size);
+
+ /*
+ * since send_pdu() could be called at least from two contexts,
+ * we need to serialize __kfifo_put, so we don't have to take
+ * additional lock on fast data-path
+ */
+ if (hdr->opcode & ISCSI_OP_IMMEDIATE)
+ __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
+ else
+ __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
+
+ scsi_queue_work(session->host, &conn->xmitwork);
+ return 0;
+}
+
+int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
+ char *data, uint32_t data_size)
+{
+ struct iscsi_conn *conn = cls_conn->dd_data;
+ int rc;
+
+ mutex_lock(&conn->xmitmutex);
+ rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
+ mutex_unlock(&conn->xmitmutex);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
+
+void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
+{
+ struct iscsi_session *session = class_to_transport_session(cls_session);
+ struct iscsi_conn *conn = session->leadconn;
+
+ spin_lock_bh(&session->lock);
+ if (session->state != ISCSI_STATE_LOGGED_IN) {
+ session->state = ISCSI_STATE_RECOVERY_FAILED;
+ if (conn)
+ wake_up(&conn->ehwait);
+ }
+ spin_unlock_bh(&session->lock);
+}
+EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
+
+int iscsi_eh_host_reset(struct scsi_cmnd *sc)
+{
+ struct Scsi_Host *host = sc->device->host;
+ struct iscsi_session *session = iscsi_hostdata(host->hostdata);
+ struct iscsi_conn *conn = session->leadconn;
+ int fail_session = 0;
+
+ spin_lock_bh(&session->lock);
+ if (session->state == ISCSI_STATE_TERMINATE) {
+failed:
+ debug_scsi("failing host reset: session terminated "
+ "[CID %d age %d]", conn->id, session->age);
+ spin_unlock_bh(&session->lock);
+ return FAILED;
+ }
+
+ if (sc->SCp.phase == session->age) {
+ debug_scsi("failing connection CID %d due to SCSI host reset",
+ conn->id);
+ fail_session = 1;
+ }
+ spin_unlock_bh(&session->lock);
+
+ /*
+ * we drop the lock here but the leadconn cannot be destoyed while
+ * we are in the scsi eh
+ */
+ if (fail_session)
+ iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+
+ debug_scsi("iscsi_eh_host_reset wait for relogin\n");
+ wait_event_interruptible(conn->ehwait,
+ session->state == ISCSI_STATE_TERMINATE ||
+ session->state == ISCSI_STATE_LOGGED_IN ||
+ session->state == ISCSI_STATE_RECOVERY_FAILED);
+ if (signal_pending(current))
+ flush_signals(current);
+
+ spin_lock_bh(&session->lock);
+ if (session->state == ISCSI_STATE_LOGGED_IN)
+ printk(KERN_INFO "iscsi: host reset succeeded\n");
+ else
+ goto failed;
+ spin_unlock_bh(&session->lock);
+
+ return SUCCESS;
+}
+EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
+
+static void iscsi_tmabort_timedout(unsigned long data)
+{
+ struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
+ struct iscsi_conn *conn = ctask->conn;
+ struct iscsi_session *session = conn->session;
+
+ spin_lock(&session->lock);
+ if (conn->tmabort_state == TMABORT_INITIAL) {
+ conn->tmabort_state = TMABORT_TIMEDOUT;
+ debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
+ ctask->sc, ctask->itt);
+ /* unblock eh_abort() */
+ wake_up(&conn->ehwait);
+ }
+ spin_unlock(&session->lock);
+}
+
+/* must be called with the mutex lock */
+static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
+ struct iscsi_cmd_task *ctask)
+{
+ struct iscsi_conn *conn = ctask->conn;
+ struct iscsi_session *session = conn->session;
+ struct iscsi_tm *hdr = &conn->tmhdr;
+ int rc;
+
+ /*
+ * ctask timed out but session is OK 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, sizeof(hdr->lun));
+ hdr->rtt = ctask->hdr->itt;
+ hdr->refcmdsn = ctask->hdr->cmdsn;
+
+ rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
+ NULL, 0);
+ if (rc) {
+ iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+ debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
+ return rc;
+ }
+
+ debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
+
+ spin_lock_bh(&session->lock);
+ ctask->mtask = (struct iscsi_mgmt_task *)
+ session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
+ ISCSI_MGMT_ITT_OFFSET];
+
+ if (conn->tmabort_state == TMABORT_INITIAL) {
+ conn->tmfcmd_pdus_cnt++;
+ conn->tmabort_timer.expires = 10*HZ + jiffies;
+ conn->tmabort_timer.function = iscsi_tmabort_timedout;
+ conn->tmabort_timer.data = (unsigned long)ctask;
+ add_timer(&conn->tmabort_timer);
+ debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
+ }
+ spin_unlock_bh(&session->lock);
+ mutex_unlock(&conn->xmitmutex);
+
+ /*
+ * block eh thread until:
+ *
+ * 1) abort response
+ * 2) abort timeout
+ * 3) session is terminated or restarted or userspace has
+ * given up on recovery
+ */
+ wait_event_interruptible(conn->ehwait,
+ sc->SCp.phase != session->age ||
+ session->state != ISCSI_STATE_LOGGED_IN ||
+ conn->tmabort_state != TMABORT_INITIAL);
+ if (signal_pending(current))
+ flush_signals(current);
+ del_timer_sync(&conn->tmabort_timer);
+
+ mutex_lock(&conn->xmitmutex);
+ return 0;
+}
+
+/*
+ * xmit mutex and session lock must be held
+ */
+#define iscsi_remove_task(tasktype) \
+static struct iscsi_##tasktype * \
+iscsi_remove_##tasktype(struct kfifo *fifo, uint32_t itt) \
+{ \
+ int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*); \
+ struct iscsi_##tasktype *task; \
+ \
+ debug_scsi("searching %d tasks\n", nr_tasks); \
+ \
+ for (i = 0; i < nr_tasks; i++) { \
+ __kfifo_get(fifo, (void*)&task, sizeof(void*)); \
+ debug_scsi("check task %u\n", task->itt); \
+ \
+ if (task->itt == itt) { \
+ debug_scsi("matched task\n"); \
+ return task; \
+ } \
+ \
+ __kfifo_put(fifo, (void*)&task, sizeof(void*)); \
+ } \
+ return NULL; \
+}
+
+iscsi_remove_task(mgmt_task);
+iscsi_remove_task(cmd_task);
+
+static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
+{
+ struct iscsi_conn *conn = ctask->conn;
+ struct iscsi_session *session = conn->session;
+
+ if (!ctask->mtask)
+ return -EINVAL;
+
+ if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
+ list_del(&ctask->mtask->running);
+ __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
+ sizeof(void*));
+ ctask->mtask = NULL;
+ return 0;
+}
+
+/*
+ * session lock and xmitmutex must be held
+ */
+static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
+ int err)
+{
+ struct scsi_cmnd *sc;
+
+ conn->session->tt->cleanup_cmd_task(conn, ctask);
+ iscsi_ctask_mtask_cleanup(ctask);
+
+ sc = ctask->sc;
+ if (!sc)
+ return;
+ sc->result = err;
+ sc->resid = sc->request_bufflen;
+ iscsi_complete_command(conn->session, ctask);
+}
+
+int iscsi_eh_abort(struct scsi_cmnd *sc)
+{
+ struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
+ struct iscsi_conn *conn = ctask->conn;
+ struct iscsi_session *session = conn->session;
+ struct iscsi_cmd_task *pending_ctask;
+ int rc;
+
+ conn->eh_abort_cnt++;
+ debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
+
+ mutex_lock(&conn->xmitmutex);
+ spin_lock_bh(&session->lock);
+
+ /*
+ * If we are not logged in or we have started a new session
+ * then let the host reset code handle this
+ */
+ if (session->state != ISCSI_STATE_LOGGED_IN ||
+ sc->SCp.phase != session->age)
+ goto failed;
+
+ /* ctask completed before time out */
+ if (!ctask->sc)
+ goto success;
+
+ /* what should we do here ? */
+ if (conn->ctask == ctask) {
+ printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. "
+ "Failing abort\n", sc, ctask->itt);
+ goto failed;
+ }
+
+ /* check for the easy pending cmd abort */
+ pending_ctask = iscsi_remove_cmd_task(conn->xmitqueue, ctask->itt);
+ if (pending_ctask) {
+ /* iscsi_tcp queues write transfers on the xmitqueue */
+ if (list_empty(&pending_ctask->running)) {
+ debug_scsi("found pending task\n");
+ goto success;
+ } else
+ __kfifo_put(conn->xmitqueue, (void*)&pending_ctask,
+ sizeof(void*));
+ }
+
+ conn->tmabort_state = TMABORT_INITIAL;
+
+ spin_unlock_bh(&session->lock);
+ rc = iscsi_exec_abort_task(sc, ctask);
+ spin_lock_bh(&session->lock);
+
+ iscsi_ctask_mtask_cleanup(ctask);
+ if (rc || sc->SCp.phase != session->age ||
+ session->state != ISCSI_STATE_LOGGED_IN)
+ goto failed;
+
+ /* ctask completed before tmf abort response */
+ if (!ctask->sc) {
+ debug_scsi("sc completed while abort in progress\n");
+ goto success;
+ }
+
+ if (conn->tmabort_state != TMABORT_SUCCESS) {
+ spin_unlock_bh(&session->lock);
+ iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+ spin_lock_bh(&session->lock);
+ goto failed;
+ }
+
+success:
+ debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
+ spin_unlock_bh(&session->lock);
+
+ /*
+ * clean up task if aborted. we have the xmitmutex so grab
+ * the recv lock as a writer
+ */
+ write_lock_bh(conn->recv_lock);
+ spin_lock(&session->lock);
+ fail_command(conn, ctask, DID_ABORT << 16);
+ spin_unlock(&session->lock);
+ write_unlock_bh(conn->recv_lock);
+
+ mutex_unlock(&conn->xmitmutex);
+ return SUCCESS;
+
+failed:
+ spin_unlock_bh(&session->lock);
+ mutex_unlock(&conn->xmitmutex);
+
+ debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
+ return FAILED;
+}
+EXPORT_SYMBOL_GPL(iscsi_eh_abort);
+
+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;
+}
+EXPORT_SYMBOL_GPL(iscsi_pool_init);
+
+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);
+}
+EXPORT_SYMBOL_GPL(iscsi_pool_free);
+
+/*
+ * iSCSI Session's hostdata organization:
+ *
+ * *------------------* <== hostdata_session(host->hostdata)
+ * | ptr to class sess|
+ * |------------------| <== iscsi_hostdata(host->hostdata)
+ * | iscsi_session |
+ * *------------------*
+ */
+
+#define hostdata_privsize(_sz) (sizeof(unsigned long) + _sz + \
+ _sz % sizeof(unsigned long))
+
+#define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
+
+/**
+ * iscsi_session_setup - create iscsi cls session and host and session
+ * @scsit: scsi transport template
+ * @iscsit: iscsi transport template
+ * @initial_cmdsn: initial CmdSN
+ * @hostno: host no allocated
+ *
+ * This can be used by software iscsi_transports that allocate
+ * a session per scsi host.
+ **/
+struct iscsi_cls_session *
+iscsi_session_setup(struct iscsi_transport *iscsit,
+ struct scsi_transport_template *scsit,
+ int cmd_task_size, int mgmt_task_size,
+ uint32_t initial_cmdsn, uint32_t *hostno)
+{
+ struct Scsi_Host *shost;
+ struct iscsi_session *session;
+ struct iscsi_cls_session *cls_session;
+ int cmd_i;
+
+ shost = scsi_host_alloc(iscsit->host_template,
+ hostdata_privsize(sizeof(*session)));
+ if (!shost)
+ return NULL;
+
+ shost->max_id = 1;
+ shost->max_channel = 0;
+ shost->max_lun = iscsit->max_lun;
+ shost->max_cmd_len = iscsit->max_cmd_len;
+ shost->transportt = scsit;
+ shost->transportt->create_work_queue = 1;
+ *hostno = shost->host_no;
+
+ session = iscsi_hostdata(shost->hostdata);
+ memset(session, 0, sizeof(struct iscsi_session));
+ session->host = shost;
+ session->state = ISCSI_STATE_FREE;
+ 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;
+ session->tt = iscsit;
+
+ /* initialize SCSI PDU commands pool */
+ if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
+ (void***)&session->cmds,
+ cmd_task_size + 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++) {
+ struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
+
+ if (cmd_task_size)
+ ctask->dd_data = &ctask[1];
+ ctask->itt = cmd_i;
+ }
+
+ spin_lock_init(&session->lock);
+ INIT_LIST_HEAD(&session->connections);
+
+ /* initialize immediate command pool */
+ if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
+ (void***)&session->mgmt_cmds,
+ mgmt_task_size + 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++) {
+ struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
+
+ if (mgmt_task_size)
+ mtask->dd_data = &mtask[1];
+ mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
+ }
+
+ if (scsi_add_host(shost, NULL))
+ goto add_host_fail;
+
+ cls_session = iscsi_create_session(shost, iscsit, 0);
+ if (!cls_session)
+ goto cls_session_fail;
+ *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
+
+ return cls_session;
+
+cls_session_fail:
+ scsi_remove_host(shost);
+add_host_fail:
+ iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
+mgmtpool_alloc_fail:
+ iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
+cmdpool_alloc_fail:
+ scsi_host_put(shost);
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(iscsi_session_setup);
+
+/**
+ * iscsi_session_teardown - destroy session, host, and cls_session
+ * shost: scsi host
+ *
+ * This can be used by software iscsi_transports that allocate
+ * a session per scsi host.
+ **/
+void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
+{
+ struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
+ struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
+
+ scsi_remove_host(shost);
+
+ iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
+ iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
+
+ iscsi_destroy_session(cls_session);
+ scsi_host_put(shost);
+}
+EXPORT_SYMBOL_GPL(iscsi_session_teardown);
+
+/**
+ * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
+ * @cls_session: iscsi_cls_session
+ * @conn_idx: cid
+ **/
+struct iscsi_cls_conn *
+iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
+{
+ struct iscsi_session *session = class_to_transport_session(cls_session);
+ struct iscsi_conn *conn;
+ struct iscsi_cls_conn *cls_conn;
+ char *data;
+
+ cls_conn = iscsi_create_conn(cls_session, conn_idx);
+ if (!cls_conn)
+ return NULL;
+ conn = cls_conn->dd_data;
+ memset(conn, 0, sizeof(*conn));
+
+ conn->session = session;
+ conn->cls_conn = cls_conn;
+ conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
+ conn->id = conn_idx;
+ conn->exp_statsn = 0;
+ conn->tmabort_state = TMABORT_INITIAL;
+ INIT_LIST_HEAD(&conn->run_list);
+ INIT_LIST_HEAD(&conn->mgmt_run_list);
+
+ /* 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 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);
+
+ data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
+ if (!data)
+ goto login_mtask_data_alloc_fail;
+ conn->login_mtask->data = data;
+
+ init_timer(&conn->tmabort_timer);
+ mutex_init(&conn->xmitmutex);
+ init_waitqueue_head(&conn->ehwait);
+
+ return cls_conn;
+
+login_mtask_data_alloc_fail:
+ __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
+ sizeof(void*));
+login_mtask_alloc_fail:
+ kfifo_free(conn->mgmtqueue);
+mgmtqueue_alloc_fail:
+ kfifo_free(conn->immqueue);
+immqueue_alloc_fail:
+ kfifo_free(conn->xmitqueue);
+xmitqueue_alloc_fail:
+ iscsi_destroy_conn(cls_conn);
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_setup);
+
+/**
+ * iscsi_conn_teardown - teardown iscsi connection
+ * cls_conn: iscsi class connection
+ *
+ * TODO: we may need to make this into a two step process
+ * like scsi-mls remove + put host
+ */
+void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
+{
+ struct iscsi_conn *conn = cls_conn->dd_data;
+ struct iscsi_session *session = conn->session;
+ unsigned long flags;
+
+ set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+ mutex_lock(&conn->xmitmutex);
+ if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE) {
+ if (session->tt->suspend_conn_recv)
+ session->tt->suspend_conn_recv(conn);
+
+ session->tt->terminate_conn(conn);
+ }
+
+ spin_lock_bh(&session->lock);
+ conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
+ if (session->leadconn == conn) {
+ /*
+ * leading connection? then give up on recovery.
+ */
+ session->state = ISCSI_STATE_TERMINATE;
+ wake_up(&conn->ehwait);
+ }
+ spin_unlock_bh(&session->lock);
+
+ mutex_unlock(&conn->xmitmutex);
+
+ /*
+ * Block until all in-progress commands for this connection
+ * time out or fail.
+ */
+ for (;;) {
+ spin_lock_irqsave(session->host->host_lock, flags);
+ if (!session->host->host_busy) { /* OK for ERL == 0 */
+ spin_unlock_irqrestore(session->host->host_lock, flags);
+ break;
+ }
+ spin_unlock_irqrestore(session->host->host_lock, flags);
+ msleep_interruptible(500);
+ printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d "
+ "host_failed %d\n", session->host->host_busy,
+ session->host->host_failed);
+ /*
+ * force eh_abort() to unblock
+ */
+ wake_up(&conn->ehwait);
+ }
+
+ spin_lock_bh(&session->lock);
+ kfree(conn->login_mtask->data);
+ __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
+ sizeof(void*));
+ 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);
+
+ if (session->leadconn == NULL)
+ /* no connections exits.. reset sequencing */
+ session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
+ spin_unlock_bh(&session->lock);
+
+ kfifo_free(conn->xmitqueue);
+ kfifo_free(conn->immqueue);
+ kfifo_free(conn->mgmtqueue);
+
+ iscsi_destroy_conn(cls_conn);
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
+
+int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
+{
+ struct iscsi_conn *conn = cls_conn->dd_data;
+ struct iscsi_session *session = conn->session;
+
+ if (session == NULL) {
+ printk(KERN_ERR "iscsi: can't start unbound connection\n");
+ return -EPERM;
+ }
+
+ spin_lock_bh(&session->lock);
+ conn->c_stage = ISCSI_CONN_STARTED;
+ session->state = ISCSI_STATE_LOGGED_IN;
+
+ switch(conn->stop_stage) {
+ case STOP_CONN_RECOVER:
+ /*
+ * unblock eh_abort() if it is blocked. re-try all
+ * commands after successful recovery
+ */
+ conn->stop_stage = 0;
+ conn->tmabort_state = TMABORT_INITIAL;
+ session->age++;
+ spin_unlock_bh(&session->lock);
+
+ iscsi_unblock_session(session_to_cls(session));
+ wake_up(&conn->ehwait);
+ return 0;
+ case STOP_CONN_TERM:
+ conn->stop_stage = 0;
+ break;
+ default:
+ break;
+ }
+ spin_unlock_bh(&session->lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_start);
+
+static void
+flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
+{
+ struct iscsi_mgmt_task *mtask, *tmp;
+
+ /* handle pending */
+ while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
+ __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
+ if (mtask == conn->login_mtask)
+ continue;
+ debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
+ __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
+ sizeof(void*));
+ }
+
+ /* handle running */
+ list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
+ debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
+ list_del(&mtask->running);
+
+ if (mtask == conn->login_mtask)
+ continue;
+ __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
+ sizeof(void*));
+ }
+
+ conn->mtask = NULL;
+}
+
+/* Fail commands. Mutex and session lock held and recv side suspended */
+static void fail_all_commands(struct iscsi_conn *conn)
+{
+ struct iscsi_cmd_task *ctask, *tmp;
+
+ /* flush pending */
+ while (__kfifo_get(conn->xmitqueue, (void*)&ctask, sizeof(void*))) {
+ debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
+ ctask->itt);
+ fail_command(conn, ctask, DID_BUS_BUSY << 16);
+ }
+
+ /* fail all other running */
+ list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
+ debug_scsi("failing in progress sc %p itt 0x%x\n",
+ ctask->sc, ctask->itt);
+ fail_command(conn, ctask, DID_BUS_BUSY << 16);
+ }
+
+ conn->ctask = NULL;
+}
+
+static void iscsi_start_session_recovery(struct iscsi_session *session,
+ struct iscsi_conn *conn, int flag)
+{
+ int old_stop_stage;
+
+ spin_lock_bh(&session->lock);
+ if (conn->stop_stage == STOP_CONN_TERM) {
+ spin_unlock_bh(&session->lock);
+ return;
+ }
+
+ /*
+ * When this is called for the in_login state, we only want to clean
+ * up the login task and connection. We do not need to block and set
+ * the recovery state again
+ */
+ if (flag == STOP_CONN_TERM)
+ session->state = ISCSI_STATE_TERMINATE;
+ else if (conn->stop_stage != STOP_CONN_RECOVER)
+ session->state = ISCSI_STATE_IN_RECOVERY;
+
+ old_stop_stage = conn->stop_stage;
+ conn->stop_stage = flag;
+ conn->c_stage = ISCSI_CONN_STOPPED;
+ set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+ spin_unlock_bh(&session->lock);
+
+ if (session->tt->suspend_conn_recv)
+ session->tt->suspend_conn_recv(conn);
+
+ mutex_lock(&conn->xmitmutex);
+ /*
+ * 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_CONN_RECOVER) {
+ conn->hdrdgst_en = 0;
+ conn->datadgst_en = 0;
+ if (session->state == ISCSI_STATE_IN_RECOVERY &&
+ old_stop_stage != STOP_CONN_RECOVER) {
+ debug_scsi("blocking session\n");
+ iscsi_block_session(session_to_cls(session));
+ }
+ }
+
+ session->tt->terminate_conn(conn);
+ /*
+ * flush queues.
+ */
+ spin_lock_bh(&session->lock);
+ fail_all_commands(conn);
+ flush_control_queues(session, conn);
+ spin_unlock_bh(&session->lock);
+
+ mutex_unlock(&conn->xmitmutex);
+}
+
+void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
+{
+ struct iscsi_conn *conn = cls_conn->dd_data;
+ struct iscsi_session *session = conn->session;
+
+ switch (flag) {
+ case STOP_CONN_RECOVER:
+ case STOP_CONN_TERM:
+ iscsi_start_session_recovery(session, conn, flag);
+ break;
+ default:
+ printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag);
+ }
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_stop);
+
+int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
+ struct iscsi_cls_conn *cls_conn, int is_leading)
+{
+ struct iscsi_session *session = class_to_transport_session(cls_session);
+ struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data;
+
+ /* lookup for existing connection */
+ spin_lock_bh(&session->lock);
+ list_for_each_entry(tmp, &session->connections, item) {
+ if (tmp == conn) {
+ if (conn->c_stage != ISCSI_CONN_STOPPED ||
+ conn->stop_stage == STOP_CONN_TERM) {
+ printk(KERN_ERR "iscsi: can't bind "
+ "non-stopped connection (%d:%d)\n",
+ conn->c_stage, conn->stop_stage);
+ spin_unlock_bh(&session->lock);
+ return -EIO;
+ }
+ break;
+ }
+ }
+ if (tmp != conn) {
+ /* bind new iSCSI connection to session */
+ conn->session = session;
+ list_add(&conn->item, &session->connections);
+ }
+ spin_unlock_bh(&session->lock);
+
+ if (is_leading)
+ session->leadconn = conn;
+
+ /*
+ * Unblock xmitworker(), Login Phase will pass through.
+ */
+ clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
+ clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_bind);
+
+MODULE_AUTHOR("Mike Christie");
+MODULE_DESCRIPTION("iSCSI library functions");
+MODULE_LICENSE("GPL");
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