[deliverable/linux.git] / drivers / target / tcm_fc / tfc_cmd.c

/*
 * Copyright (c) 2010 Cisco Systems, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 */

/* XXX TBD some includes may be extraneous */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/version.h>
#include <generated/utsrelease.h>
#include <linux/utsname.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kthread.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/configfs.h>
#include <linux/ctype.h>
#include <linux/hash.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_tcq.h>
#include <scsi/libfc.h>
#include <scsi/fc_encode.h>

#include <target/target_core_base.h>
#include <target/target_core_transport.h>
#include <target/target_core_fabric_ops.h>
#include <target/target_core_device.h>
#include <target/target_core_tpg.h>
#include <target/target_core_configfs.h>
#include <target/target_core_tmr.h>
#include <target/configfs_macros.h>

#include "tcm_fc.h"

/*
 * Dump cmd state for debugging.
 */
void ft_dump_cmd(struct ft_cmd *cmd, const char *caller)
{
	struct fc_exch *ep;
	struct fc_seq *sp;
	struct se_cmd *se_cmd;
	struct scatterlist *sg;
	int count;

	se_cmd = &cmd->se_cmd;
	pr_debug("%s: cmd %p state %d sess %p seq %p se_cmd %p\n",
		caller, cmd, cmd->state, cmd->sess, cmd->seq, se_cmd);
	pr_debug("%s: cmd %p cdb %p\n",
		caller, cmd, cmd->cdb);
	pr_debug("%s: cmd %p lun %d\n", caller, cmd, cmd->lun);

	pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n",
		caller, cmd, se_cmd->t_data_nents,
	       se_cmd->data_length, se_cmd->se_cmd_flags);

	for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count)
		pr_debug("%s: cmd %p sg %p page %p "
			"len 0x%x off 0x%x\n",
			caller, cmd, sg,
			sg_page(sg), sg->length, sg->offset);

	sp = cmd->seq;
	if (sp) {
		ep = fc_seq_exch(sp);
		pr_debug("%s: cmd %p sid %x did %x "
			"ox_id %x rx_id %x seq_id %x e_stat %x\n",
			caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
			sp->id, ep->esb_stat);
	}
	print_hex_dump(KERN_INFO, "ft_dump_cmd ", DUMP_PREFIX_NONE,
		16, 4, cmd->cdb, MAX_COMMAND_SIZE, 0);
}

static void ft_queue_cmd(struct ft_sess *sess, struct ft_cmd *cmd)
{
	struct ft_tpg *tpg = sess->tport->tpg;
	struct se_queue_obj *qobj = &tpg->qobj;
	unsigned long flags;

	qobj = &sess->tport->tpg->qobj;
	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
	list_add_tail(&cmd->se_req.qr_list, &qobj->qobj_list);
	atomic_inc(&qobj->queue_cnt);
	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);

	wake_up_process(tpg->thread);
}

static struct ft_cmd *ft_dequeue_cmd(struct se_queue_obj *qobj)
{
	unsigned long flags;
	struct se_queue_req *qr;

	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
	if (list_empty(&qobj->qobj_list)) {
		spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
		return NULL;
	}
	qr = list_first_entry(&qobj->qobj_list, struct se_queue_req, qr_list);
	list_del(&qr->qr_list);
	atomic_dec(&qobj->queue_cnt);
	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
	return container_of(qr, struct ft_cmd, se_req);
}

static void ft_free_cmd(struct ft_cmd *cmd)
{
	struct fc_frame *fp;
	struct fc_lport *lport;

	if (!cmd)
		return;
	fp = cmd->req_frame;
	lport = fr_dev(fp);
	if (fr_seq(fp))
		lport->tt.seq_release(fr_seq(fp));
	fc_frame_free(fp);
	ft_sess_put(cmd->sess);	/* undo get from lookup at recv */
	kfree(cmd);
}

void ft_release_cmd(struct se_cmd *se_cmd)
{
	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);

	ft_free_cmd(cmd);
}

void ft_check_stop_free(struct se_cmd *se_cmd)
{
	transport_generic_free_cmd(se_cmd, 0, 0);
}

/*
 * Send response.
 */
int ft_queue_status(struct se_cmd *se_cmd)
{
	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	struct fc_frame *fp;
	struct fcp_resp_with_ext *fcp;
	struct fc_lport *lport;
	struct fc_exch *ep;
	size_t len;

	ft_dump_cmd(cmd, __func__);
	ep = fc_seq_exch(cmd->seq);
	lport = ep->lp;
	len = sizeof(*fcp) + se_cmd->scsi_sense_length;
	fp = fc_frame_alloc(lport, len);
	if (!fp) {
		/* XXX shouldn't just drop it - requeue and retry? */
		return 0;
	}
	fcp = fc_frame_payload_get(fp, len);
	memset(fcp, 0, len);
	fcp->resp.fr_status = se_cmd->scsi_status;

	len = se_cmd->scsi_sense_length;
	if (len) {
		fcp->resp.fr_flags |= FCP_SNS_LEN_VAL;
		fcp->ext.fr_sns_len = htonl(len);
		memcpy((fcp + 1), se_cmd->sense_buffer, len);
	}

	/*
	 * Test underflow and overflow with one mask.  Usually both are off.
	 * Bidirectional commands are not handled yet.
	 */
	if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT | SCF_UNDERFLOW_BIT)) {
		if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
			fcp->resp.fr_flags |= FCP_RESID_OVER;
		else
			fcp->resp.fr_flags |= FCP_RESID_UNDER;
		fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
	}

	/*
	 * Send response.
	 */
	cmd->seq = lport->tt.seq_start_next(cmd->seq);
	fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
		       FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ, 0);

	lport->tt.seq_send(lport, cmd->seq, fp);
	lport->tt.exch_done(cmd->seq);
	return 0;
}

int ft_write_pending_status(struct se_cmd *se_cmd)
{
	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);

	return cmd->write_data_len != se_cmd->data_length;
}

/*
 * Send TX_RDY (transfer ready).
 */
int ft_write_pending(struct se_cmd *se_cmd)
{
	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	struct fc_frame *fp;
	struct fcp_txrdy *txrdy;
	struct fc_lport *lport;
	struct fc_exch *ep;
	struct fc_frame_header *fh;
	u32 f_ctl;

	ft_dump_cmd(cmd, __func__);

	ep = fc_seq_exch(cmd->seq);
	lport = ep->lp;
	fp = fc_frame_alloc(lport, sizeof(*txrdy));
	if (!fp)
		return PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;

	txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
	memset(txrdy, 0, sizeof(*txrdy));
	txrdy->ft_burst_len = htonl(se_cmd->data_length);

	cmd->seq = lport->tt.seq_start_next(cmd->seq);
	fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
		       FC_FC_EX_CTX | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);

	fh = fc_frame_header_get(fp);
	f_ctl = ntoh24(fh->fh_f_ctl);

	/* Only if it is 'Exchange Responder' */
	if (f_ctl & FC_FC_EX_CTX) {
		/* Target is 'exchange responder' and sending XFER_READY
		 * to 'exchange initiator (initiator)'
		 */
		if ((ep->xid <= lport->lro_xid) &&
		    (fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
			if (se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
				/*
				 * cmd may have been broken up into multiple
				 * tasks. Link their sgs together so we can
				 * operate on them all at once.
				 */
				transport_do_task_sg_chain(se_cmd);
				cmd->sg = se_cmd->t_tasks_sg_chained;
				cmd->sg_cnt =
					se_cmd->t_tasks_sg_chained_no;
			}
			if (cmd->sg && lport->tt.ddp_target(lport, ep->xid,
							    cmd->sg,
							    cmd->sg_cnt))
				cmd->was_ddp_setup = 1;
		}
	}
	lport->tt.seq_send(lport, cmd->seq, fp);
	return 0;
}

u32 ft_get_task_tag(struct se_cmd *se_cmd)
{
	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);

	return fc_seq_exch(cmd->seq)->rxid;
}

int ft_get_cmd_state(struct se_cmd *se_cmd)
{
	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);

	return cmd->state;
}

int ft_is_state_remove(struct se_cmd *se_cmd)
{
	return 0;	/* XXX TBD */
}

/*
 * FC sequence response handler for follow-on sequences (data) and aborts.
 */
static void ft_recv_seq(struct fc_seq *sp, struct fc_frame *fp, void *arg)
{
	struct ft_cmd *cmd = arg;
	struct fc_frame_header *fh;

	if (IS_ERR(fp)) {
		/* XXX need to find cmd if queued */
		cmd->se_cmd.t_state = TRANSPORT_REMOVE;
		cmd->seq = NULL;
		transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
		return;
	}

	fh = fc_frame_header_get(fp);

	switch (fh->fh_r_ctl) {
	case FC_RCTL_DD_SOL_DATA:	/* write data */
		ft_recv_write_data(cmd, fp);
		break;
	case FC_RCTL_DD_UNSOL_CTL:	/* command */
	case FC_RCTL_DD_SOL_CTL:	/* transfer ready */
	case FC_RCTL_DD_DATA_DESC:	/* transfer ready */
	default:
		pr_debug("%s: unhandled frame r_ctl %x\n",
		       __func__, fh->fh_r_ctl);
		ft_invl_hw_context(cmd);
		fc_frame_free(fp);
		transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
		break;
	}
}

/*
 * Send a FCP response including SCSI status and optional FCP rsp_code.
 * status is SAM_STAT_GOOD (zero) iff code is valid.
 * This is used in error cases, such as allocation failures.
 */
static void ft_send_resp_status(struct fc_lport *lport,
				const struct fc_frame *rx_fp,
				u32 status, enum fcp_resp_rsp_codes code)
{
	struct fc_frame *fp;
	struct fc_seq *sp;
	const struct fc_frame_header *fh;
	size_t len;
	struct fcp_resp_with_ext *fcp;
	struct fcp_resp_rsp_info *info;

	fh = fc_frame_header_get(rx_fp);
	pr_debug("FCP error response: did %x oxid %x status %x code %x\n",
		  ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
	len = sizeof(*fcp);
	if (status == SAM_STAT_GOOD)
		len += sizeof(*info);
	fp = fc_frame_alloc(lport, len);
	if (!fp)
		return;
	fcp = fc_frame_payload_get(fp, len);
	memset(fcp, 0, len);
	fcp->resp.fr_status = status;
	if (status == SAM_STAT_GOOD) {
		fcp->ext.fr_rsp_len = htonl(sizeof(*info));
		fcp->resp.fr_flags |= FCP_RSP_LEN_VAL;
		info = (struct fcp_resp_rsp_info *)(fcp + 1);
		info->rsp_code = code;
	}

	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
	sp = fr_seq(fp);
	if (sp)
		lport->tt.seq_send(lport, sp, fp);
	else
		lport->tt.frame_send(lport, fp);
}

/*
 * Send error or task management response.
 */
static void ft_send_resp_code(struct ft_cmd *cmd,
			      enum fcp_resp_rsp_codes code)
{
	ft_send_resp_status(cmd->sess->tport->lport,
			    cmd->req_frame, SAM_STAT_GOOD, code);
}


/*
 * Send error or task management response.
 * Always frees the cmd and associated state.
 */
static void ft_send_resp_code_and_free(struct ft_cmd *cmd,
				      enum fcp_resp_rsp_codes code)
{
	ft_send_resp_code(cmd, code);
	ft_free_cmd(cmd);
}

/*
 * Handle Task Management Request.
 */
static void ft_send_tm(struct ft_cmd *cmd)
{
	struct se_tmr_req *tmr;
	struct fcp_cmnd *fcp;
	struct ft_sess *sess;
	u8 tm_func;

	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));

	switch (fcp->fc_tm_flags) {
	case FCP_TMF_LUN_RESET:
		tm_func = TMR_LUN_RESET;
		break;
	case FCP_TMF_TGT_RESET:
		tm_func = TMR_TARGET_WARM_RESET;
		break;
	case FCP_TMF_CLR_TASK_SET:
		tm_func = TMR_CLEAR_TASK_SET;
		break;
	case FCP_TMF_ABT_TASK_SET:
		tm_func = TMR_ABORT_TASK_SET;
		break;
	case FCP_TMF_CLR_ACA:
		tm_func = TMR_CLEAR_ACA;
		break;
	default:
		/*
		 * FCP4r01 indicates having a combination of
		 * tm_flags set is invalid.
		 */
		pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
		ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
		return;
	}

	pr_debug("alloc tm cmd fn %d\n", tm_func);
	tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func);
	if (!tmr) {
		pr_debug("alloc failed\n");
		ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
		return;
	}
	cmd->se_cmd.se_tmr_req = tmr;

	switch (fcp->fc_tm_flags) {
	case FCP_TMF_LUN_RESET:
		cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
		if (transport_lookup_tmr_lun(&cmd->se_cmd, cmd->lun) < 0) {
			/*
			 * Make sure to clean up newly allocated TMR request
			 * since "unable to  handle TMR request because failed
			 * to get to LUN"
			 */
			pr_debug("Failed to get LUN for TMR func %d, "
				  "se_cmd %p, unpacked_lun %d\n",
				  tm_func, &cmd->se_cmd, cmd->lun);
			ft_dump_cmd(cmd, __func__);
			sess = cmd->sess;
			transport_send_check_condition_and_sense(&cmd->se_cmd,
				cmd->se_cmd.scsi_sense_reason, 0);
			transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
			ft_sess_put(sess);
			return;
		}
		break;
	case FCP_TMF_TGT_RESET:
	case FCP_TMF_CLR_TASK_SET:
	case FCP_TMF_ABT_TASK_SET:
	case FCP_TMF_CLR_ACA:
		break;
	default:
		return;
	}
	transport_generic_handle_tmr(&cmd->se_cmd);
}

/*
 * Send status from completed task management request.
 */
int ft_queue_tm_resp(struct se_cmd *se_cmd)
{
	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	struct se_tmr_req *tmr = se_cmd->se_tmr_req;
	enum fcp_resp_rsp_codes code;

	switch (tmr->response) {
	case TMR_FUNCTION_COMPLETE:
		code = FCP_TMF_CMPL;
		break;
	case TMR_LUN_DOES_NOT_EXIST:
		code = FCP_TMF_INVALID_LUN;
		break;
	case TMR_FUNCTION_REJECTED:
		code = FCP_TMF_REJECTED;
		break;
	case TMR_TASK_DOES_NOT_EXIST:
	case TMR_TASK_STILL_ALLEGIANT:
	case TMR_TASK_FAILOVER_NOT_SUPPORTED:
	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
	case TMR_FUNCTION_AUTHORIZATION_FAILED:
	default:
		code = FCP_TMF_FAILED;
		break;
	}
	pr_debug("tmr fn %d resp %d fcp code %d\n",
		  tmr->function, tmr->response, code);
	ft_send_resp_code(cmd, code);
	return 0;
}

/*
 * Handle incoming FCP command.
 */
static void ft_recv_cmd(struct ft_sess *sess, struct fc_frame *fp)
{
	struct ft_cmd *cmd;
	struct fc_lport *lport = sess->tport->lport;

	cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
	if (!cmd)
		goto busy;
	cmd->sess = sess;
	cmd->seq = lport->tt.seq_assign(lport, fp);
	if (!cmd->seq) {
		kfree(cmd);
		goto busy;
	}
	cmd->req_frame = fp;		/* hold frame during cmd */
	ft_queue_cmd(sess, cmd);
	return;

busy:
	pr_debug("cmd or seq allocation failure - sending BUSY\n");
	ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
	fc_frame_free(fp);
	ft_sess_put(sess);		/* undo get from lookup */
}


/*
 * Handle incoming FCP frame.
 * Caller has verified that the frame is type FCP.
 */
void ft_recv_req(struct ft_sess *sess, struct fc_frame *fp)
{
	struct fc_frame_header *fh = fc_frame_header_get(fp);

	switch (fh->fh_r_ctl) {
	case FC_RCTL_DD_UNSOL_CMD:	/* command */
		ft_recv_cmd(sess, fp);
		break;
	case FC_RCTL_DD_SOL_DATA:	/* write data */
	case FC_RCTL_DD_UNSOL_CTL:
	case FC_RCTL_DD_SOL_CTL:
	case FC_RCTL_DD_DATA_DESC:	/* transfer ready */
	case FC_RCTL_ELS4_REQ:		/* SRR, perhaps */
	default:
		pr_debug("%s: unhandled frame r_ctl %x\n",
		       __func__, fh->fh_r_ctl);
		fc_frame_free(fp);
		ft_sess_put(sess);	/* undo get from lookup */
		break;
	}
}

/*
 * Send new command to target.
 */
static void ft_send_cmd(struct ft_cmd *cmd)
{
	struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
	struct se_cmd *se_cmd;
	struct fcp_cmnd *fcp;
	int data_dir;
	u32 data_len;
	int task_attr;
	int ret;

	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
	if (!fcp)
		goto err;

	if (fcp->fc_flags & FCP_CFL_LEN_MASK)
		goto err;		/* not handling longer CDBs yet */

	if (fcp->fc_tm_flags) {
		task_attr = FCP_PTA_SIMPLE;
		data_dir = DMA_NONE;
		data_len = 0;
	} else {
		switch (fcp->fc_flags & (FCP_CFL_RDDATA | FCP_CFL_WRDATA)) {
		case 0:
			data_dir = DMA_NONE;
			break;
		case FCP_CFL_RDDATA:
			data_dir = DMA_FROM_DEVICE;
			break;
		case FCP_CFL_WRDATA:
			data_dir = DMA_TO_DEVICE;
			break;
		case FCP_CFL_WRDATA | FCP_CFL_RDDATA:
			goto err;	/* TBD not supported by tcm_fc yet */
		}
		/*
		 * Locate the SAM Task Attr from fc_pri_ta
		 */
		switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
		case FCP_PTA_HEADQ:
			task_attr = MSG_HEAD_TAG;
			break;
		case FCP_PTA_ORDERED:
			task_attr = MSG_ORDERED_TAG;
			break;
		case FCP_PTA_ACA:
			task_attr = MSG_ACA_TAG;
			break;
		case FCP_PTA_SIMPLE: /* Fallthrough */
		default:
			task_attr = MSG_SIMPLE_TAG;
		}


		task_attr = fcp->fc_pri_ta & FCP_PTA_MASK;
		data_len = ntohl(fcp->fc_dl);
		cmd->cdb = fcp->fc_cdb;
	}

	se_cmd = &cmd->se_cmd;
	/*
	 * Initialize struct se_cmd descriptor from target_core_mod
	 * infrastructure
	 */
	transport_init_se_cmd(se_cmd, &ft_configfs->tf_ops, cmd->sess->se_sess,
			      data_len, data_dir, task_attr,
			      &cmd->ft_sense_buffer[0]);
	/*
	 * Check for FCP task management flags
	 */
	if (fcp->fc_tm_flags) {
		ft_send_tm(cmd);
		return;
	}

	fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);

	cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
	ret = transport_lookup_cmd_lun(&cmd->se_cmd, cmd->lun);
	if (ret < 0) {
		ft_dump_cmd(cmd, __func__);
		transport_send_check_condition_and_sense(&cmd->se_cmd,
			cmd->se_cmd.scsi_sense_reason, 0);
		return;
	}

	ret = transport_generic_allocate_tasks(se_cmd, cmd->cdb);

	pr_debug("r_ctl %x alloc task ret %d\n", fh->fh_r_ctl, ret);
	ft_dump_cmd(cmd, __func__);

	if (ret == -ENOMEM) {
		transport_send_check_condition_and_sense(se_cmd,
				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
		transport_generic_free_cmd(se_cmd, 0, 0);
		return;
	}
	if (ret == -EINVAL) {
		if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
			ft_queue_status(se_cmd);
		else
			transport_send_check_condition_and_sense(se_cmd,
					se_cmd->scsi_sense_reason, 0);
		transport_generic_free_cmd(se_cmd, 0, 0);
		return;
	}
	transport_generic_handle_cdb(se_cmd);
	return;

err:
	ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
}

/*
 * Handle request in the command thread.
 */
static void ft_exec_req(struct ft_cmd *cmd)
{
	pr_debug("cmd state %x\n", cmd->state);
	switch (cmd->state) {
	case FC_CMD_ST_NEW:
		ft_send_cmd(cmd);
		break;
	default:
		break;
	}
}

/*
 * Processing thread.
 * Currently one thread per tpg.
 */
int ft_thread(void *arg)
{
	struct ft_tpg *tpg = arg;
	struct se_queue_obj *qobj = &tpg->qobj;
	struct ft_cmd *cmd;

	while (!kthread_should_stop()) {
		schedule_timeout_interruptible(MAX_SCHEDULE_TIMEOUT);
		if (kthread_should_stop())
			goto out;

		cmd = ft_dequeue_cmd(qobj);
		if (cmd)
			ft_exec_req(cmd);
	}

out:
	return 0;
}
Commit	Line	Data
3699d92a KP	1	/*
	2	* Copyright (c) 2010 Cisco Systems, Inc.
	3	*
	4	* This program is free software; you can redistribute it and/or modify it
	5	* under the terms and conditions of the GNU General Public License,
	6	* version 2, as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope it will be useful, but WITHOUT
	9	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	10	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	11	* more details.
	12	*
	13	* You should have received a copy of the GNU General Public License along with
	14	* this program; if not, write to the Free Software Foundation, Inc.,
	15	* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
	16	*/
	17
	18	/* XXX TBD some includes may be extraneous */
	19
	20	#include <linux/module.h>
	21	#include <linux/moduleparam.h>
	22	#include <linux/version.h>
	23	#include <generated/utsrelease.h>
	24	#include <linux/utsname.h>
	25	#include <linux/init.h>
	26	#include <linux/slab.h>
	27	#include <linux/kthread.h>
	28	#include <linux/types.h>
	29	#include <linux/string.h>
	30	#include <linux/configfs.h>
	31	#include <linux/ctype.h>
	32	#include <linux/hash.h>
	33	#include <asm/unaligned.h>
	34	#include <scsi/scsi.h>
	35	#include <scsi/scsi_host.h>
	36	#include <scsi/scsi_device.h>
	37	#include <scsi/scsi_cmnd.h>
61db1802	38	#include <scsi/scsi_tcq.h>
3699d92a KP	39	#include <scsi/libfc.h>
	40	#include <scsi/fc_encode.h>
	41
	42	#include <target/target_core_base.h>
	43	#include <target/target_core_transport.h>
	44	#include <target/target_core_fabric_ops.h>
	45	#include <target/target_core_device.h>
	46	#include <target/target_core_tpg.h>
	47	#include <target/target_core_configfs.h>
3699d92a KP	48	#include <target/target_core_tmr.h>
	49	#include <target/configfs_macros.h>
	50
	51	#include "tcm_fc.h"
	52
	53	/*
	54	* Dump cmd state for debugging.
	55	*/
	56	void ft_dump_cmd(struct ft_cmd cmd, const char caller)
	57	{
	58	struct fc_exch *ep;
	59	struct fc_seq *sp;
	60	struct se_cmd *se_cmd;
ec98f782 AG	61	struct scatterlist *sg;
ec98f782 AG	62	int count;
3699d92a	63
3699d92a	64	se_cmd = &cmd->se_cmd;
6708bb27	65	pr_debug("%s: cmd %p state %d sess %p seq %p se_cmd %p\n",
3699d92a	66	caller, cmd, cmd->state, cmd->sess, cmd->seq, se_cmd);
6708bb27	67	pr_debug("%s: cmd %p cdb %p\n",
3699d92a	68	caller, cmd, cmd->cdb);
6708bb27	69	pr_debug("%s: cmd %p lun %d\n", caller, cmd, cmd->lun);
3699d92a	70
6708bb27	71	pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n",
ec98f782	72	caller, cmd, se_cmd->t_data_nents,
05d1c7c0	73	se_cmd->data_length, se_cmd->se_cmd_flags);
5951146d	74
ec98f782	75	for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count)
6708bb27	76	pr_debug("%s: cmd %p sg %p page %p "
ec98f782 AG	77	"len 0x%x off 0x%x\n",
	78	caller, cmd, sg,
	79	sg_page(sg), sg->length, sg->offset);
	80
3699d92a KP	81	sp = cmd->seq;
	82	if (sp) {
	83	ep = fc_seq_exch(sp);
6708bb27	84	pr_debug("%s: cmd %p sid %x did %x "
3699d92a KP	85	"ox_id %x rx_id %x seq_id %x e_stat %x\n",
	86	caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
	87	sp->id, ep->esb_stat);
	88	}
	89	print_hex_dump(KERN_INFO, "ft_dump_cmd ", DUMP_PREFIX_NONE,
	90	16, 4, cmd->cdb, MAX_COMMAND_SIZE, 0);
	91	}
	92
3699d92a KP	93	static void ft_queue_cmd(struct ft_sess sess, struct ft_cmd cmd)
3699d92a KP	94	{
2be18149 NB	95	struct ft_tpg *tpg = sess->tport->tpg;
2be18149 NB	96	struct se_queue_obj *qobj = &tpg->qobj;
3699d92a KP	97	unsigned long flags;
	98
	99	qobj = &sess->tport->tpg->qobj;
	100	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
	101	list_add_tail(&cmd->se_req.qr_list, &qobj->qobj_list);
3699d92a	102	atomic_inc(&qobj->queue_cnt);
2be18149 NB	103	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
	104
	105	wake_up_process(tpg->thread);
3699d92a KP	106	}
	107
	108	static struct ft_cmd ft_dequeue_cmd(struct se_queue_obj qobj)
	109	{
	110	unsigned long flags;
	111	struct se_queue_req *qr;
	112
	113	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
	114	if (list_empty(&qobj->qobj_list)) {
	115	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
	116	return NULL;
	117	}
	118	qr = list_first_entry(&qobj->qobj_list, struct se_queue_req, qr_list);
	119	list_del(&qr->qr_list);
	120	atomic_dec(&qobj->queue_cnt);
	121	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
	122	return container_of(qr, struct ft_cmd, se_req);
	123	}
	124
	125	static void ft_free_cmd(struct ft_cmd *cmd)
	126	{
	127	struct fc_frame *fp;
	128	struct fc_lport *lport;
	129
	130	if (!cmd)
	131	return;
	132	fp = cmd->req_frame;
	133	lport = fr_dev(fp);
	134	if (fr_seq(fp))
	135	lport->tt.seq_release(fr_seq(fp));
	136	fc_frame_free(fp);
	137	ft_sess_put(cmd->sess); /* undo get from lookup at recv */
	138	kfree(cmd);
	139	}
	140
	141	void ft_release_cmd(struct se_cmd *se_cmd)
	142	{
	143	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	144
	145	ft_free_cmd(cmd);
	146	}
	147
	148	void ft_check_stop_free(struct se_cmd *se_cmd)
	149	{
35462975	150	transport_generic_free_cmd(se_cmd, 0, 0);
3699d92a KP	151	}
	152
	153	/*
	154	* Send response.
	155	*/
	156	int ft_queue_status(struct se_cmd *se_cmd)
	157	{
	158	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	159	struct fc_frame *fp;
	160	struct fcp_resp_with_ext *fcp;
	161	struct fc_lport *lport;
	162	struct fc_exch *ep;
	163	size_t len;
	164
	165	ft_dump_cmd(cmd, __func__);
	166	ep = fc_seq_exch(cmd->seq);
	167	lport = ep->lp;
	168	len = sizeof(*fcp) + se_cmd->scsi_sense_length;
	169	fp = fc_frame_alloc(lport, len);
	170	if (!fp) {
	171	/* XXX shouldn't just drop it - requeue and retry? */
	172	return 0;
	173	}
	174	fcp = fc_frame_payload_get(fp, len);
	175	memset(fcp, 0, len);
	176	fcp->resp.fr_status = se_cmd->scsi_status;
	177
	178	len = se_cmd->scsi_sense_length;
	179	if (len) {
	180	fcp->resp.fr_flags \|= FCP_SNS_LEN_VAL;
	181	fcp->ext.fr_sns_len = htonl(len);
	182	memcpy((fcp + 1), se_cmd->sense_buffer, len);
	183	}
	184
	185	/*
	186	* Test underflow and overflow with one mask. Usually both are off.
	187	* Bidirectional commands are not handled yet.
	188	*/
	189	if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT \| SCF_UNDERFLOW_BIT)) {
	190	if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
	191	fcp->resp.fr_flags \|= FCP_RESID_OVER;
	192	else
	193	fcp->resp.fr_flags \|= FCP_RESID_UNDER;
	194	fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
	195	}
	196
	197	/*
	198	* Send response.
	199	*/
	200	cmd->seq = lport->tt.seq_start_next(cmd->seq);
	201	fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
	202	FC_FC_EX_CTX \| FC_FC_LAST_SEQ \| FC_FC_END_SEQ, 0);
	203
	204	lport->tt.seq_send(lport, cmd->seq, fp);
	205	lport->tt.exch_done(cmd->seq);
	206	return 0;
	207	}
	208
	209	int ft_write_pending_status(struct se_cmd *se_cmd)
	210	{
	211	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	212
	213	return cmd->write_data_len != se_cmd->data_length;
	214	}
215
216	/*
217	* Send TX_RDY (transfer ready).
218	*/
219	int ft_write_pending(struct se_cmd *se_cmd)
220	{
221	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
222	struct fc_frame *fp;
223	struct fcp_txrdy *txrdy;
224	struct fc_lport *lport;
225	struct fc_exch *ep;
226	struct fc_frame_header *fh;
227	u32 f_ctl;
228
229	ft_dump_cmd(cmd, __func__);
230
231	ep = fc_seq_exch(cmd->seq);
232	lport = ep->lp;
233	fp = fc_frame_alloc(lport, sizeof(*txrdy));
234	if (!fp)
235	return PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
236
237	txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
238	memset(txrdy, 0, sizeof(*txrdy));
239	txrdy->ft_burst_len = htonl(se_cmd->data_length);
240
241	cmd->seq = lport->tt.seq_start_next(cmd->seq);
242	fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
243	FC_FC_EX_CTX \| FC_FC_END_SEQ \| FC_FC_SEQ_INIT, 0);
244
245	fh = fc_frame_header_get(fp);
246	f_ctl = ntoh24(fh->fh_f_ctl);
247
248	/* Only if it is 'Exchange Responder' */
249	if (f_ctl & FC_FC_EX_CTX) {
250	/* Target is 'exchange responder' and sending XFER_READY
251	* to 'exchange initiator (initiator)'
252	*/
253	if ((ep->xid <= lport->lro_xid) &&
254	(fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
255	if (se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
256	/*
ec98f782 AG	257	* cmd may have been broken up into multiple
	258	* tasks. Link their sgs together so we can
	259	* operate on them all at once.
3699d92a KP	260	*/
3699d92a KP	261	transport_do_task_sg_chain(se_cmd);
a1d8b49a	262	cmd->sg = se_cmd->t_tasks_sg_chained;
3699d92a	263	cmd->sg_cnt =
a1d8b49a	264	se_cmd->t_tasks_sg_chained_no;
3699d92a	265	}
33dc362b YZ	266	if (cmd->sg && lport->tt.ddp_target(lport, ep->xid,
	267	cmd->sg,
	268	cmd->sg_cnt))
3699d92a KP	269	cmd->was_ddp_setup = 1;
	270	}
	271	}
	272	lport->tt.seq_send(lport, cmd->seq, fp);
	273	return 0;
	274	}
	275
	276	u32 ft_get_task_tag(struct se_cmd *se_cmd)
	277	{
	278	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	279
	280	return fc_seq_exch(cmd->seq)->rxid;
	281	}
	282
	283	int ft_get_cmd_state(struct se_cmd *se_cmd)
	284	{
	285	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	286
	287	return cmd->state;
	288	}
	289
	290	int ft_is_state_remove(struct se_cmd *se_cmd)
	291	{
	292	return 0; /* XXX TBD */
	293	}
	294
3699d92a KP	295	/*
	296	* FC sequence response handler for follow-on sequences (data) and aborts.
	297	*/
	298	static void ft_recv_seq(struct fc_seq sp, struct fc_frame fp, void *arg)
	299	{
	300	struct ft_cmd *cmd = arg;
	301	struct fc_frame_header *fh;
	302
	303	if (IS_ERR(fp)) {
	304	/* XXX need to find cmd if queued */
	305	cmd->se_cmd.t_state = TRANSPORT_REMOVE;
	306	cmd->seq = NULL;
35462975	307	transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
3699d92a KP	308	return;
	309	}
	310
	311	fh = fc_frame_header_get(fp);
	312
	313	switch (fh->fh_r_ctl) {
	314	case FC_RCTL_DD_SOL_DATA: /* write data */
	315	ft_recv_write_data(cmd, fp);
	316	break;
	317	case FC_RCTL_DD_UNSOL_CTL: /* command */
	318	case FC_RCTL_DD_SOL_CTL: /* transfer ready */
	319	case FC_RCTL_DD_DATA_DESC: /* transfer ready */
	320	default:
6708bb27	321	pr_debug("%s: unhandled frame r_ctl %x\n",
3699d92a	322	__func__, fh->fh_r_ctl);
dcd998cc	323	ft_invl_hw_context(cmd);
3699d92a	324	fc_frame_free(fp);
35462975	325	transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
3699d92a KP	326	break;
	327	}
	328	}
	329
	330	/*
	331	* Send a FCP response including SCSI status and optional FCP rsp_code.
	332	* status is SAM_STAT_GOOD (zero) iff code is valid.
	333	* This is used in error cases, such as allocation failures.
	334	*/
	335	static void ft_send_resp_status(struct fc_lport *lport,
	336	const struct fc_frame *rx_fp,
	337	u32 status, enum fcp_resp_rsp_codes code)
	338	{
	339	struct fc_frame *fp;
	340	struct fc_seq *sp;
	341	const struct fc_frame_header *fh;
	342	size_t len;
	343	struct fcp_resp_with_ext *fcp;
	344	struct fcp_resp_rsp_info *info;
	345
	346	fh = fc_frame_header_get(rx_fp);
6708bb27	347	pr_debug("FCP error response: did %x oxid %x status %x code %x\n",
3699d92a KP	348	ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
	349	len = sizeof(*fcp);
	350	if (status == SAM_STAT_GOOD)
	351	len += sizeof(*info);
	352	fp = fc_frame_alloc(lport, len);
	353	if (!fp)
	354	return;
	355	fcp = fc_frame_payload_get(fp, len);
	356	memset(fcp, 0, len);
	357	fcp->resp.fr_status = status;
	358	if (status == SAM_STAT_GOOD) {
	359	fcp->ext.fr_rsp_len = htonl(sizeof(*info));
	360	fcp->resp.fr_flags \|= FCP_RSP_LEN_VAL;
	361	info = (struct fcp_resp_rsp_info *)(fcp + 1);
	362	info->rsp_code = code;
	363	}
	364
	365	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
	366	sp = fr_seq(fp);
	367	if (sp)
	368	lport->tt.seq_send(lport, sp, fp);
	369	else
	370	lport->tt.frame_send(lport, fp);
	371	}
	372
	373	/*
	374	* Send error or task management response.
3699d92a	375	*/
f2f7b09c KP	376	static void ft_send_resp_code(struct ft_cmd *cmd,
f2f7b09c KP	377	enum fcp_resp_rsp_codes code)
3699d92a KP	378	{
	379	ft_send_resp_status(cmd->sess->tport->lport,
	380	cmd->req_frame, SAM_STAT_GOOD, code);
f2f7b09c KP	381	}
	382
	383
	384	/*
	385	* Send error or task management response.
	386	* Always frees the cmd and associated state.
	387	*/
	388	static void ft_send_resp_code_and_free(struct ft_cmd *cmd,
	389	enum fcp_resp_rsp_codes code)
	390	{
	391	ft_send_resp_code(cmd, code);
3699d92a KP	392	ft_free_cmd(cmd);
	393	}
	394
	395	/*
	396	* Handle Task Management Request.
	397	*/
	398	static void ft_send_tm(struct ft_cmd *cmd)
	399	{
	400	struct se_tmr_req *tmr;
	401	struct fcp_cmnd *fcp;
61db9527	402	struct ft_sess *sess;
3699d92a KP	403	u8 tm_func;
	404
	405	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
	406
	407	switch (fcp->fc_tm_flags) {
	408	case FCP_TMF_LUN_RESET:
	409	tm_func = TMR_LUN_RESET;
3699d92a KP	410	break;
	411	case FCP_TMF_TGT_RESET:
	412	tm_func = TMR_TARGET_WARM_RESET;
	413	break;
	414	case FCP_TMF_CLR_TASK_SET:
	415	tm_func = TMR_CLEAR_TASK_SET;
	416	break;
	417	case FCP_TMF_ABT_TASK_SET:
	418	tm_func = TMR_ABORT_TASK_SET;
	419	break;
	420	case FCP_TMF_CLR_ACA:
	421	tm_func = TMR_CLEAR_ACA;
	422	break;
	423	default:
	424	/*
	425	* FCP4r01 indicates having a combination of
	426	* tm_flags set is invalid.
	427	*/
6708bb27	428	pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
f2f7b09c	429	ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
3699d92a KP	430	return;
	431	}
	432
6708bb27	433	pr_debug("alloc tm cmd fn %d\n", tm_func);
3699d92a KP	434	tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func);
3699d92a KP	435	if (!tmr) {
6708bb27	436	pr_debug("alloc failed\n");
f2f7b09c	437	ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
3699d92a KP	438	return;
	439	}
	440	cmd->se_cmd.se_tmr_req = tmr;
61db9527 KP	441
	442	switch (fcp->fc_tm_flags) {
	443	case FCP_TMF_LUN_RESET:
	444	cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
5951146d	445	if (transport_lookup_tmr_lun(&cmd->se_cmd, cmd->lun) < 0) {
61db9527 KP	446	/*
	447	* Make sure to clean up newly allocated TMR request
	448	* since "unable to handle TMR request because failed
	449	* to get to LUN"
	450	*/
6708bb27	451	pr_debug("Failed to get LUN for TMR func %d, "
61db9527 KP	452	"se_cmd %p, unpacked_lun %d\n",
	453	tm_func, &cmd->se_cmd, cmd->lun);
	454	ft_dump_cmd(cmd, __func__);
	455	sess = cmd->sess;
	456	transport_send_check_condition_and_sense(&cmd->se_cmd,
	457	cmd->se_cmd.scsi_sense_reason, 0);
35462975	458	transport_generic_free_cmd(&cmd->se_cmd, 0, 0);
61db9527 KP	459	ft_sess_put(sess);
	460	return;
	461	}
	462	break;
	463	case FCP_TMF_TGT_RESET:
	464	case FCP_TMF_CLR_TASK_SET:
	465	case FCP_TMF_ABT_TASK_SET:
	466	case FCP_TMF_CLR_ACA:
	467	break;
	468	default:
	469	return;
	470	}
3699d92a KP	471	transport_generic_handle_tmr(&cmd->se_cmd);
	472	}
	473
	474	/*
	475	* Send status from completed task management request.
	476	*/
	477	int ft_queue_tm_resp(struct se_cmd *se_cmd)
	478	{
	479	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	480	struct se_tmr_req *tmr = se_cmd->se_tmr_req;
	481	enum fcp_resp_rsp_codes code;
	482
	483	switch (tmr->response) {
	484	case TMR_FUNCTION_COMPLETE:
	485	code = FCP_TMF_CMPL;
	486	break;
	487	case TMR_LUN_DOES_NOT_EXIST:
	488	code = FCP_TMF_INVALID_LUN;
	489	break;
	490	case TMR_FUNCTION_REJECTED:
	491	code = FCP_TMF_REJECTED;
	492	break;
	493	case TMR_TASK_DOES_NOT_EXIST:
	494	case TMR_TASK_STILL_ALLEGIANT:
	495	case TMR_TASK_FAILOVER_NOT_SUPPORTED:
	496	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
	497	case TMR_FUNCTION_AUTHORIZATION_FAILED:
	498	default:
	499	code = FCP_TMF_FAILED;
	500	break;
	501	}
6708bb27	502	pr_debug("tmr fn %d resp %d fcp code %d\n",
3699d92a KP	503	tmr->function, tmr->response, code);
	504	ft_send_resp_code(cmd, code);
	505	return 0;
	506	}
	507
	508	/*
	509	* Handle incoming FCP command.
	510	*/
	511	static void ft_recv_cmd(struct ft_sess sess, struct fc_frame fp)
	512	{
	513	struct ft_cmd *cmd;
	514	struct fc_lport *lport = sess->tport->lport;
	515
	516	cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
	517	if (!cmd)
	518	goto busy;
	519	cmd->sess = sess;
	520	cmd->seq = lport->tt.seq_assign(lport, fp);
	521	if (!cmd->seq) {
	522	kfree(cmd);
	523	goto busy;
	524	}
	525	cmd->req_frame = fp; /* hold frame during cmd */
	526	ft_queue_cmd(sess, cmd);
	527	return;
	528
	529	busy:
6708bb27	530	pr_debug("cmd or seq allocation failure - sending BUSY\n");
3699d92a KP	531	ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
	532	fc_frame_free(fp);
	533	ft_sess_put(sess); /* undo get from lookup */
	534	}
	535
	536
	537	/*
	538	* Handle incoming FCP frame.
	539	* Caller has verified that the frame is type FCP.
	540	*/
	541	void ft_recv_req(struct ft_sess sess, struct fc_frame fp)
	542	{
	543	struct fc_frame_header *fh = fc_frame_header_get(fp);
	544
	545	switch (fh->fh_r_ctl) {
	546	case FC_RCTL_DD_UNSOL_CMD: /* command */
	547	ft_recv_cmd(sess, fp);
	548	break;
	549	case FC_RCTL_DD_SOL_DATA: /* write data */
	550	case FC_RCTL_DD_UNSOL_CTL:
	551	case FC_RCTL_DD_SOL_CTL:
	552	case FC_RCTL_DD_DATA_DESC: /* transfer ready */
	553	case FC_RCTL_ELS4_REQ: /* SRR, perhaps */
	554	default:
6708bb27	555	pr_debug("%s: unhandled frame r_ctl %x\n",
3699d92a KP	556	__func__, fh->fh_r_ctl);
	557	fc_frame_free(fp);
	558	ft_sess_put(sess); /* undo get from lookup */
	559	break;
	560	}
	561	}
	562
	563	/*
	564	* Send new command to target.
	565	*/
	566	static void ft_send_cmd(struct ft_cmd *cmd)
	567	{
	568	struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
	569	struct se_cmd *se_cmd;
	570	struct fcp_cmnd *fcp;
	571	int data_dir;
	572	u32 data_len;
	573	int task_attr;
	574	int ret;
	575
	576	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
	577	if (!fcp)
	578	goto err;
	579
	580	if (fcp->fc_flags & FCP_CFL_LEN_MASK)
	581	goto err; /* not handling longer CDBs yet */
	582
	583	if (fcp->fc_tm_flags) {
	584	task_attr = FCP_PTA_SIMPLE;
	585	data_dir = DMA_NONE;
	586	data_len = 0;
	587	} else {
	588	switch (fcp->fc_flags & (FCP_CFL_RDDATA \| FCP_CFL_WRDATA)) {
	589	case 0:
	590	data_dir = DMA_NONE;
	591	break;
	592	case FCP_CFL_RDDATA:
	593	data_dir = DMA_FROM_DEVICE;
	594	break;
	595	case FCP_CFL_WRDATA:
	596	data_dir = DMA_TO_DEVICE;
	597	break;
	598	case FCP_CFL_WRDATA \| FCP_CFL_RDDATA:
	599	goto err; /* TBD not supported by tcm_fc yet */
	600	}
61db1802 NB	601	/*
	602	* Locate the SAM Task Attr from fc_pri_ta
	603	*/
	604	switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
	605	case FCP_PTA_HEADQ:
	606	task_attr = MSG_HEAD_TAG;
	607	break;
	608	case FCP_PTA_ORDERED:
	609	task_attr = MSG_ORDERED_TAG;
	610	break;
	611	case FCP_PTA_ACA:
	612	task_attr = MSG_ACA_TAG;
	613	break;
	614	case FCP_PTA_SIMPLE: /* Fallthrough */
	615	default:
	616	task_attr = MSG_SIMPLE_TAG;
	617	}
	618
3699d92a	619
3699d92a KP	620	task_attr = fcp->fc_pri_ta & FCP_PTA_MASK;
	621	data_len = ntohl(fcp->fc_dl);
	622	cmd->cdb = fcp->fc_cdb;
	623	}
	624
	625	se_cmd = &cmd->se_cmd;
	626	/*
	627	* Initialize struct se_cmd descriptor from target_core_mod
	628	* infrastructure
	629	*/
	630	transport_init_se_cmd(se_cmd, &ft_configfs->tf_ops, cmd->sess->se_sess,
	631	data_len, data_dir, task_attr,
	632	&cmd->ft_sense_buffer[0]);
	633	/*
	634	* Check for FCP task management flags
	635	*/
	636	if (fcp->fc_tm_flags) {
	637	ft_send_tm(cmd);
	638	return;
	639	}
	640
	641	fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);
	642
61db9527	643	cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
5951146d	644	ret = transport_lookup_cmd_lun(&cmd->se_cmd, cmd->lun);
3699d92a KP	645	if (ret < 0) {
	646	ft_dump_cmd(cmd, __func__);
	647	transport_send_check_condition_and_sense(&cmd->se_cmd,
	648	cmd->se_cmd.scsi_sense_reason, 0);
	649	return;
	650	}
	651
	652	ret = transport_generic_allocate_tasks(se_cmd, cmd->cdb);
	653
6708bb27	654	pr_debug("r_ctl %x alloc task ret %d\n", fh->fh_r_ctl, ret);
3699d92a KP	655	ft_dump_cmd(cmd, __func__);
3699d92a KP	656
5951146d	657	if (ret == -ENOMEM) {
3699d92a KP	658	transport_send_check_condition_and_sense(se_cmd,
3699d92a KP	659	TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
35462975	660	transport_generic_free_cmd(se_cmd, 0, 0);
3699d92a KP	661	return;
3699d92a KP	662	}
5951146d	663	if (ret == -EINVAL) {
3699d92a KP	664	if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
	665	ft_queue_status(se_cmd);
	666	else
	667	transport_send_check_condition_and_sense(se_cmd,
	668	se_cmd->scsi_sense_reason, 0);
35462975	669	transport_generic_free_cmd(se_cmd, 0, 0);
3699d92a KP	670	return;
	671	}
	672	transport_generic_handle_cdb(se_cmd);
	673	return;
	674
	675	err:
f2f7b09c	676	ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
3699d92a KP	677	}
	678
	679	/*
	680	* Handle request in the command thread.
	681	*/
	682	static void ft_exec_req(struct ft_cmd *cmd)
	683	{
6708bb27	684	pr_debug("cmd state %x\n", cmd->state);
3699d92a KP	685	switch (cmd->state) {
	686	case FC_CMD_ST_NEW:
	687	ft_send_cmd(cmd);
	688	break;
	689	default:
	690	break;
	691	}
	692	}
	693
	694	/*
	695	* Processing thread.
	696	* Currently one thread per tpg.
	697	*/
	698	int ft_thread(void *arg)
	699	{
	700	struct ft_tpg *tpg = arg;
	701	struct se_queue_obj *qobj = &tpg->qobj;
	702	struct ft_cmd *cmd;
3699d92a KP	703
3699d92a KP	704	while (!kthread_should_stop()) {
2be18149 NB	705	schedule_timeout_interruptible(MAX_SCHEDULE_TIMEOUT);
2be18149 NB	706	if (kthread_should_stop())
3699d92a	707	goto out;
2be18149	708
3699d92a KP	709	cmd = ft_dequeue_cmd(qobj);
	710	if (cmd)
	711	ft_exec_req(cmd);
	712	}
	713
	714	out:
	715	return 0;
	716	}