[linux-2.6-block.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 <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_fabric.h>
#include <target/target_core_configfs.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 sess %p seq %p se_cmd %p\n",
		caller, cmd, cmd->sess, cmd->seq, se_cmd);

	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);
	}
}

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);
}

int ft_check_stop_free(struct se_cmd *se_cmd)
{
	transport_generic_free_cmd(se_cmd, 0);
	return 1;
}

/*
 * 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;

	if (cmd->aborted)
		return 0;
	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__);

	if (cmd->aborted)
		return 0;
	ep = fc_seq_exch(cmd->seq);
	lport = ep->lp;
	fp = fc_frame_alloc(lport, sizeof(*txrdy));
	if (!fp)
		return -ENOMEM; /* Signal QUEUE_FULL */

	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_CDB) &&
			    lport->tt.ddp_target(lport, ep->xid,
						 se_cmd->t_data_sg,
						 se_cmd->t_data_nents))
				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);

	if (cmd->aborted)
		return ~0;
	return fc_seq_exch(cmd->seq)->rxid;
}

int ft_get_cmd_state(struct se_cmd *se_cmd)
{
	return 0;
}

/*
 * 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 (unlikely(IS_ERR(fp))) {
		/* XXX need to find cmd if queued */
		cmd->seq = NULL;
		cmd->aborted = true;
		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);
		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);
		lport->tt.exch_done(sp);
	} 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 fcp_cmnd *fcp;
	int rc;
	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;
	}

	/* FIXME: Add referenced task tag for ABORT_TASK */
	rc = target_submit_tmr(&cmd->se_cmd, cmd->sess->se_sess,
		&cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
		cmd, tm_func, GFP_KERNEL, 0, 0);
	if (rc < 0)
		ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
}

/*
 * 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;

	if (cmd->aborted)
		return 0;
	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;
}

static void ft_send_work(struct work_struct *work);

/*
 * 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 */

	INIT_WORK(&cmd->work, ft_send_work);
	queue_work(sess->tport->tpg->workqueue, &cmd->work);
	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_work(struct work_struct *work)
{
	struct ft_cmd *cmd = container_of(work, struct ft_cmd, work);
	struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
	struct fcp_cmnd *fcp;
	int data_dir = 0;
	int task_attr;

	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 */

	/*
	 * Check for FCP task management flags
	 */
	if (fcp->fc_tm_flags) {
		ft_send_tm(cmd);
		return;
	}

	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;
	}

	fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);
	/*
	 * Use a single se_cmd->cmd_kref as we expect to release se_cmd
	 * directly from ft_check_stop_free callback in response path.
	 */
	if (target_submit_cmd(&cmd->se_cmd, cmd->sess->se_sess, fcp->fc_cdb,
			      &cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
			      ntohl(fcp->fc_dl), task_attr, data_dir, 0))
		goto err;

	pr_debug("r_ctl %x alloc target_submit_cmd\n", fh->fh_r_ctl);
	return;

err:
	ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
}
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>
3699d92a KP	22	#include <generated/utsrelease.h>
	23	#include <linux/utsname.h>
	24	#include <linux/init.h>
	25	#include <linux/slab.h>
	26	#include <linux/kthread.h>
	27	#include <linux/types.h>
	28	#include <linux/string.h>
	29	#include <linux/configfs.h>
	30	#include <linux/ctype.h>
	31	#include <linux/hash.h>
	32	#include <asm/unaligned.h>
	33	#include <scsi/scsi.h>
	34	#include <scsi/scsi_host.h>
	35	#include <scsi/scsi_device.h>
	36	#include <scsi/scsi_cmnd.h>
61db1802	37	#include <scsi/scsi_tcq.h>
3699d92a KP	38	#include <scsi/libfc.h>
	39	#include <scsi/fc_encode.h>
	40
	41	#include <target/target_core_base.h>
c4795fb2	42	#include <target/target_core_fabric.h>
3699d92a	43	#include <target/target_core_configfs.h>
3699d92a KP	44	#include <target/configfs_macros.h>
	45
	46	#include "tcm_fc.h"
	47
	48	/*
	49	* Dump cmd state for debugging.
	50	*/
	51	void ft_dump_cmd(struct ft_cmd cmd, const char caller)
	52	{
	53	struct fc_exch *ep;
	54	struct fc_seq *sp;
	55	struct se_cmd *se_cmd;
ec98f782 AG	56	struct scatterlist *sg;
ec98f782 AG	57	int count;
3699d92a	58
3699d92a	59	se_cmd = &cmd->se_cmd;
58fc73d1 CH	60	pr_debug("%s: cmd %p sess %p seq %p se_cmd %p\n",
58fc73d1 CH	61	caller, cmd, cmd->sess, cmd->seq, se_cmd);
3699d92a	62
6708bb27	63	pr_debug("%s: cmd %p data_nents %u len %u se_cmd_flags <0x%x>\n",
ec98f782	64	caller, cmd, se_cmd->t_data_nents,
05d1c7c0	65	se_cmd->data_length, se_cmd->se_cmd_flags);
5951146d	66
ec98f782	67	for_each_sg(se_cmd->t_data_sg, sg, se_cmd->t_data_nents, count)
6708bb27	68	pr_debug("%s: cmd %p sg %p page %p "
ec98f782 AG	69	"len 0x%x off 0x%x\n",
	70	caller, cmd, sg,
	71	sg_page(sg), sg->length, sg->offset);
	72
3699d92a KP	73	sp = cmd->seq;
	74	if (sp) {
	75	ep = fc_seq_exch(sp);
6708bb27	76	pr_debug("%s: cmd %p sid %x did %x "
3699d92a KP	77	"ox_id %x rx_id %x seq_id %x e_stat %x\n",
	78	caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
	79	sp->id, ep->esb_stat);
	80	}
3699d92a KP	81	}
3699d92a KP	82
3699d92a KP	83	static void ft_free_cmd(struct ft_cmd *cmd)
	84	{
	85	struct fc_frame *fp;
	86	struct fc_lport *lport;
	87
	88	if (!cmd)
	89	return;
	90	fp = cmd->req_frame;
	91	lport = fr_dev(fp);
	92	if (fr_seq(fp))
	93	lport->tt.seq_release(fr_seq(fp));
	94	fc_frame_free(fp);
	95	ft_sess_put(cmd->sess); /* undo get from lookup at recv */
	96	kfree(cmd);
	97	}
	98
	99	void ft_release_cmd(struct se_cmd *se_cmd)
	100	{
	101	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	102
	103	ft_free_cmd(cmd);
	104	}
	105
88dd9e26	106	int ft_check_stop_free(struct se_cmd *se_cmd)
3699d92a	107	{
82f1c8a4	108	transport_generic_free_cmd(se_cmd, 0);
88dd9e26	109	return 1;
3699d92a KP	110	}
	111
	112	/*
	113	* Send response.
	114	*/
	115	int ft_queue_status(struct se_cmd *se_cmd)
	116	{
	117	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	118	struct fc_frame *fp;
	119	struct fcp_resp_with_ext *fcp;
	120	struct fc_lport *lport;
	121	struct fc_exch *ep;
	122	size_t len;
	123
e1c40382 MR	124	if (cmd->aborted)
e1c40382 MR	125	return 0;
3699d92a KP	126	ft_dump_cmd(cmd, __func__);
	127	ep = fc_seq_exch(cmd->seq);
	128	lport = ep->lp;
	129	len = sizeof(*fcp) + se_cmd->scsi_sense_length;
	130	fp = fc_frame_alloc(lport, len);
	131	if (!fp) {
	132	/* XXX shouldn't just drop it - requeue and retry? */
	133	return 0;
	134	}
	135	fcp = fc_frame_payload_get(fp, len);
	136	memset(fcp, 0, len);
	137	fcp->resp.fr_status = se_cmd->scsi_status;
	138
	139	len = se_cmd->scsi_sense_length;
	140	if (len) {
	141	fcp->resp.fr_flags \|= FCP_SNS_LEN_VAL;
	142	fcp->ext.fr_sns_len = htonl(len);
	143	memcpy((fcp + 1), se_cmd->sense_buffer, len);
	144	}
	145
	146	/*
	147	* Test underflow and overflow with one mask. Usually both are off.
	148	* Bidirectional commands are not handled yet.
	149	*/
	150	if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT \| SCF_UNDERFLOW_BIT)) {
	151	if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
	152	fcp->resp.fr_flags \|= FCP_RESID_OVER;
	153	else
	154	fcp->resp.fr_flags \|= FCP_RESID_UNDER;
	155	fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
	156	}
	157
	158	/*
	159	* Send response.
	160	*/
	161	cmd->seq = lport->tt.seq_start_next(cmd->seq);
	162	fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
	163	FC_FC_EX_CTX \| FC_FC_LAST_SEQ \| FC_FC_END_SEQ, 0);
	164
	165	lport->tt.seq_send(lport, cmd->seq, fp);
	166	lport->tt.exch_done(cmd->seq);
	167	return 0;
	168	}
	169
	170	int ft_write_pending_status(struct se_cmd *se_cmd)
	171	{
	172	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	173
	174	return cmd->write_data_len != se_cmd->data_length;
	175	}
	176
	177	/*
	178	* Send TX_RDY (transfer ready).
	179	*/
	180	int ft_write_pending(struct se_cmd *se_cmd)
	181	{
	182	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	183	struct fc_frame *fp;
	184	struct fcp_txrdy *txrdy;
	185	struct fc_lport *lport;
	186	struct fc_exch *ep;
	187	struct fc_frame_header *fh;
	188	u32 f_ctl;
	189
190	ft_dump_cmd(cmd, __func__);
191
e1c40382 MR	192	if (cmd->aborted)
e1c40382 MR	193	return 0;
3699d92a KP	194	ep = fc_seq_exch(cmd->seq);
	195	lport = ep->lp;
	196	fp = fc_frame_alloc(lport, sizeof(*txrdy));
	197	if (!fp)
03e98c9e	198	return -ENOMEM; /* Signal QUEUE_FULL */
3699d92a KP	199
	200	txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
	201	memset(txrdy, 0, sizeof(*txrdy));
	202	txrdy->ft_burst_len = htonl(se_cmd->data_length);
	203
	204	cmd->seq = lport->tt.seq_start_next(cmd->seq);
	205	fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
	206	FC_FC_EX_CTX \| FC_FC_END_SEQ \| FC_FC_SEQ_INIT, 0);
	207
	208	fh = fc_frame_header_get(fp);
	209	f_ctl = ntoh24(fh->fh_f_ctl);
	210
	211	/* Only if it is 'Exchange Responder' */
	212	if (f_ctl & FC_FC_EX_CTX) {
	213	/* Target is 'exchange responder' and sending XFER_READY
	214	* to 'exchange initiator (initiator)'
	215	*/
	216	if ((ep->xid <= lport->lro_xid) &&
	217	(fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
64f1db38	218	if ((se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
e182d682 RD	219	lport->tt.ddp_target(lport, ep->xid,
	220	se_cmd->t_data_sg,
	221	se_cmd->t_data_nents))
3699d92a KP	222	cmd->was_ddp_setup = 1;
	223	}
	224	}
	225	lport->tt.seq_send(lport, cmd->seq, fp);
	226	return 0;
	227	}
	228
	229	u32 ft_get_task_tag(struct se_cmd *se_cmd)
	230	{
	231	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	232
3cc5d2a6 MR	233	if (cmd->aborted)
3cc5d2a6 MR	234	return ~0;
3699d92a KP	235	return fc_seq_exch(cmd->seq)->rxid;
	236	}
	237
	238	int ft_get_cmd_state(struct se_cmd *se_cmd)
	239	{
58fc73d1	240	return 0;
3699d92a KP	241	}
3699d92a KP	242
3699d92a KP	243	/*
	244	* FC sequence response handler for follow-on sequences (data) and aborts.
	245	*/
	246	static void ft_recv_seq(struct fc_seq sp, struct fc_frame fp, void *arg)
	247	{
	248	struct ft_cmd *cmd = arg;
	249	struct fc_frame_header *fh;
	250
e1c40382	251	if (unlikely(IS_ERR(fp))) {
3699d92a	252	/* XXX need to find cmd if queued */
3699d92a	253	cmd->seq = NULL;
e1c40382	254	cmd->aborted = true;
3699d92a KP	255	return;
	256	}
	257
	258	fh = fc_frame_header_get(fp);
	259
	260	switch (fh->fh_r_ctl) {
	261	case FC_RCTL_DD_SOL_DATA: /* write data */
	262	ft_recv_write_data(cmd, fp);
	263	break;
	264	case FC_RCTL_DD_UNSOL_CTL: /* command */
	265	case FC_RCTL_DD_SOL_CTL: /* transfer ready */
	266	case FC_RCTL_DD_DATA_DESC: /* transfer ready */
	267	default:
6708bb27	268	pr_debug("%s: unhandled frame r_ctl %x\n",
3699d92a	269	__func__, fh->fh_r_ctl);
dcd998cc	270	ft_invl_hw_context(cmd);
3699d92a	271	fc_frame_free(fp);
82f1c8a4	272	transport_generic_free_cmd(&cmd->se_cmd, 0);
3699d92a KP	273	break;
	274	}
	275	}
	276
	277	/*
	278	* Send a FCP response including SCSI status and optional FCP rsp_code.
	279	* status is SAM_STAT_GOOD (zero) iff code is valid.
	280	* This is used in error cases, such as allocation failures.
	281	*/
	282	static void ft_send_resp_status(struct fc_lport *lport,
	283	const struct fc_frame *rx_fp,
	284	u32 status, enum fcp_resp_rsp_codes code)
	285	{
	286	struct fc_frame *fp;
	287	struct fc_seq *sp;
	288	const struct fc_frame_header *fh;
	289	size_t len;
	290	struct fcp_resp_with_ext *fcp;
	291	struct fcp_resp_rsp_info *info;
	292
	293	fh = fc_frame_header_get(rx_fp);
6708bb27	294	pr_debug("FCP error response: did %x oxid %x status %x code %x\n",
3699d92a KP	295	ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
	296	len = sizeof(*fcp);
	297	if (status == SAM_STAT_GOOD)
	298	len += sizeof(*info);
	299	fp = fc_frame_alloc(lport, len);
	300	if (!fp)
	301	return;
	302	fcp = fc_frame_payload_get(fp, len);
	303	memset(fcp, 0, len);
	304	fcp->resp.fr_status = status;
	305	if (status == SAM_STAT_GOOD) {
	306	fcp->ext.fr_rsp_len = htonl(sizeof(*info));
	307	fcp->resp.fr_flags \|= FCP_RSP_LEN_VAL;
	308	info = (struct fcp_resp_rsp_info *)(fcp + 1);
	309	info->rsp_code = code;
	310	}
	311
	312	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
	313	sp = fr_seq(fp);
031ed4d5	314	if (sp) {
3699d92a	315	lport->tt.seq_send(lport, sp, fp);
031ed4d5 NB	316	lport->tt.exch_done(sp);
031ed4d5 NB	317	} else {
3699d92a	318	lport->tt.frame_send(lport, fp);
031ed4d5	319	}
3699d92a KP	320	}
	321
	322	/*
	323	* Send error or task management response.
3699d92a	324	*/
f2f7b09c KP	325	static void ft_send_resp_code(struct ft_cmd *cmd,
f2f7b09c KP	326	enum fcp_resp_rsp_codes code)
3699d92a KP	327	{
	328	ft_send_resp_status(cmd->sess->tport->lport,
	329	cmd->req_frame, SAM_STAT_GOOD, code);
f2f7b09c KP	330	}
	331
	332
	333	/*
	334	* Send error or task management response.
	335	* Always frees the cmd and associated state.
	336	*/
	337	static void ft_send_resp_code_and_free(struct ft_cmd *cmd,
	338	enum fcp_resp_rsp_codes code)
	339	{
	340	ft_send_resp_code(cmd, code);
3699d92a KP	341	ft_free_cmd(cmd);
	342	}
	343
	344	/*
	345	* Handle Task Management Request.
	346	*/
	347	static void ft_send_tm(struct ft_cmd *cmd)
	348	{
3699d92a	349	struct fcp_cmnd *fcp;
00ad4c4e	350	int rc;
3699d92a KP	351	u8 tm_func;
	352
	353	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
	354
	355	switch (fcp->fc_tm_flags) {
	356	case FCP_TMF_LUN_RESET:
	357	tm_func = TMR_LUN_RESET;
3699d92a KP	358	break;
	359	case FCP_TMF_TGT_RESET:
	360	tm_func = TMR_TARGET_WARM_RESET;
	361	break;
	362	case FCP_TMF_CLR_TASK_SET:
	363	tm_func = TMR_CLEAR_TASK_SET;
	364	break;
	365	case FCP_TMF_ABT_TASK_SET:
	366	tm_func = TMR_ABORT_TASK_SET;
	367	break;
	368	case FCP_TMF_CLR_ACA:
	369	tm_func = TMR_CLEAR_ACA;
	370	break;
	371	default:
	372	/*
	373	* FCP4r01 indicates having a combination of
	374	* tm_flags set is invalid.
	375	*/
6708bb27	376	pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
f2f7b09c	377	ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
3699d92a KP	378	return;
	379	}
	380
c0974f89	381	/* FIXME: Add referenced task tag for ABORT_TASK */
00ad4c4e	382	rc = target_submit_tmr(&cmd->se_cmd, cmd->sess->se_sess,
59dcb5ec	383	&cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
c0974f89	384	cmd, tm_func, GFP_KERNEL, 0, 0);
00ad4c4e NB	385	if (rc < 0)
00ad4c4e NB	386	ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
3699d92a KP	387	}
	388
	389	/*
	390	* Send status from completed task management request.
	391	*/
	392	int ft_queue_tm_resp(struct se_cmd *se_cmd)
	393	{
	394	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	395	struct se_tmr_req *tmr = se_cmd->se_tmr_req;
	396	enum fcp_resp_rsp_codes code;
	397
e1c40382 MR	398	if (cmd->aborted)
e1c40382 MR	399	return 0;
3699d92a KP	400	switch (tmr->response) {
	401	case TMR_FUNCTION_COMPLETE:
	402	code = FCP_TMF_CMPL;
	403	break;
	404	case TMR_LUN_DOES_NOT_EXIST:
	405	code = FCP_TMF_INVALID_LUN;
	406	break;
	407	case TMR_FUNCTION_REJECTED:
	408	code = FCP_TMF_REJECTED;
	409	break;
	410	case TMR_TASK_DOES_NOT_EXIST:
	411	case TMR_TASK_STILL_ALLEGIANT:
	412	case TMR_TASK_FAILOVER_NOT_SUPPORTED:
	413	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
	414	case TMR_FUNCTION_AUTHORIZATION_FAILED:
	415	default:
	416	code = FCP_TMF_FAILED;
	417	break;
	418	}
6708bb27	419	pr_debug("tmr fn %d resp %d fcp code %d\n",
3699d92a KP	420	tmr->function, tmr->response, code);
	421	ft_send_resp_code(cmd, code);
	422	return 0;
	423	}
	424
58fc73d1 CH	425	static void ft_send_work(struct work_struct *work);
58fc73d1 CH	426
3699d92a KP	427	/*
	428	* Handle incoming FCP command.
	429	*/
	430	static void ft_recv_cmd(struct ft_sess sess, struct fc_frame fp)
	431	{
	432	struct ft_cmd *cmd;
	433	struct fc_lport *lport = sess->tport->lport;
	434
	435	cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
	436	if (!cmd)
	437	goto busy;
	438	cmd->sess = sess;
	439	cmd->seq = lport->tt.seq_assign(lport, fp);
	440	if (!cmd->seq) {
	441	kfree(cmd);
	442	goto busy;
	443	}
	444	cmd->req_frame = fp; /* hold frame during cmd */
58fc73d1 CH	445
	446	INIT_WORK(&cmd->work, ft_send_work);
	447	queue_work(sess->tport->tpg->workqueue, &cmd->work);
3699d92a KP	448	return;
	449
	450	busy:
6708bb27	451	pr_debug("cmd or seq allocation failure - sending BUSY\n");
3699d92a KP	452	ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
	453	fc_frame_free(fp);
	454	ft_sess_put(sess); /* undo get from lookup */
	455	}
	456
	457
	458	/*
	459	* Handle incoming FCP frame.
	460	* Caller has verified that the frame is type FCP.
	461	*/
	462	void ft_recv_req(struct ft_sess sess, struct fc_frame fp)
	463	{
	464	struct fc_frame_header *fh = fc_frame_header_get(fp);
	465
	466	switch (fh->fh_r_ctl) {
	467	case FC_RCTL_DD_UNSOL_CMD: /* command */
	468	ft_recv_cmd(sess, fp);
	469	break;
	470	case FC_RCTL_DD_SOL_DATA: /* write data */
	471	case FC_RCTL_DD_UNSOL_CTL:
	472	case FC_RCTL_DD_SOL_CTL:
	473	case FC_RCTL_DD_DATA_DESC: /* transfer ready */
	474	case FC_RCTL_ELS4_REQ: /* SRR, perhaps */
	475	default:
6708bb27	476	pr_debug("%s: unhandled frame r_ctl %x\n",
3699d92a KP	477	__func__, fh->fh_r_ctl);
	478	fc_frame_free(fp);
	479	ft_sess_put(sess); /* undo get from lookup */
	480	break;
	481	}
	482	}
	483
	484	/*
	485	* Send new command to target.
	486	*/
58fc73d1	487	static void ft_send_work(struct work_struct *work)
3699d92a	488	{
58fc73d1	489	struct ft_cmd *cmd = container_of(work, struct ft_cmd, work);
3699d92a	490	struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
3699d92a	491	struct fcp_cmnd *fcp;
58fc73d1	492	int data_dir = 0;
3699d92a	493	int task_attr;
3699d92a KP	494
	495	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
	496	if (!fcp)
	497	goto err;
	498
	499	if (fcp->fc_flags & FCP_CFL_LEN_MASK)
	500	goto err; /* not handling longer CDBs yet */
	501
3699d92a KP	502	/*
	503	* Check for FCP task management flags
	504	*/
	505	if (fcp->fc_tm_flags) {
	506	ft_send_tm(cmd);
	507	return;
	508	}
0dccb69d AG	509
	510	switch (fcp->fc_flags & (FCP_CFL_RDDATA \| FCP_CFL_WRDATA)) {
	511	case 0:
	512	data_dir = DMA_NONE;
	513	break;
	514	case FCP_CFL_RDDATA:
	515	data_dir = DMA_FROM_DEVICE;
	516	break;
	517	case FCP_CFL_WRDATA:
	518	data_dir = DMA_TO_DEVICE;
	519	break;
	520	case FCP_CFL_WRDATA \| FCP_CFL_RDDATA:
	521	goto err; /* TBD not supported by tcm_fc yet */
	522	}
	523	/*
	524	* Locate the SAM Task Attr from fc_pri_ta
	525	*/
	526	switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
	527	case FCP_PTA_HEADQ:
	528	task_attr = MSG_HEAD_TAG;
	529	break;
	530	case FCP_PTA_ORDERED:
	531	task_attr = MSG_ORDERED_TAG;
	532	break;
	533	case FCP_PTA_ACA:
	534	task_attr = MSG_ACA_TAG;
	535	break;
	536	case FCP_PTA_SIMPLE: /* Fallthrough */
	537	default:
	538	task_attr = MSG_SIMPLE_TAG;
	539	}
	540
3699d92a	541	fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);
4355a911 NB	542	/*
	543	* Use a single se_cmd->cmd_kref as we expect to release se_cmd
	544	* directly from ft_check_stop_free callback in response path.
	545	*/
d6dfc868 RD	546	if (target_submit_cmd(&cmd->se_cmd, cmd->sess->se_sess, fcp->fc_cdb,
	547	&cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
	548	ntohl(fcp->fc_dl), task_attr, data_dir, 0))
	549	goto err;
	550
1edcdb49	551	pr_debug("r_ctl %x alloc target_submit_cmd\n", fh->fh_r_ctl);
3699d92a KP	552	return;
	553
	554	err:
f2f7b09c	555	ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
3699d92a	556	}