[mirror_ubuntu-bionic-kernel.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;

	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 -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_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)
{
	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 (IS_ERR(fp)) {
		/* XXX need to find cmd if queued */
		cmd->seq = NULL;
		transport_generic_free_cmd(&cmd->se_cmd, 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);
		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 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;

	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.
	 */
	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);
	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
	124	ft_dump_cmd(cmd, __func__);
	125	ep = fc_seq_exch(cmd->seq);
	126	lport = ep->lp;
	127	len = sizeof(*fcp) + se_cmd->scsi_sense_length;
	128	fp = fc_frame_alloc(lport, len);
	129	if (!fp) {
	130	/* XXX shouldn't just drop it - requeue and retry? */
	131	return 0;
	132	}
	133	fcp = fc_frame_payload_get(fp, len);
	134	memset(fcp, 0, len);
	135	fcp->resp.fr_status = se_cmd->scsi_status;
	136
	137	len = se_cmd->scsi_sense_length;
	138	if (len) {
	139	fcp->resp.fr_flags \|= FCP_SNS_LEN_VAL;
	140	fcp->ext.fr_sns_len = htonl(len);
	141	memcpy((fcp + 1), se_cmd->sense_buffer, len);
	142	}
	143
	144	/*
	145	* Test underflow and overflow with one mask. Usually both are off.
	146	* Bidirectional commands are not handled yet.
	147	*/
	148	if (se_cmd->se_cmd_flags & (SCF_OVERFLOW_BIT \| SCF_UNDERFLOW_BIT)) {
	149	if (se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT)
	150	fcp->resp.fr_flags \|= FCP_RESID_OVER;
	151	else
	152	fcp->resp.fr_flags \|= FCP_RESID_UNDER;
	153	fcp->ext.fr_resid = cpu_to_be32(se_cmd->residual_count);
	154	}
	155
	156	/*
	157	* Send response.
	158	*/
	159	cmd->seq = lport->tt.seq_start_next(cmd->seq);
	160	fc_fill_fc_hdr(fp, FC_RCTL_DD_CMD_STATUS, ep->did, ep->sid, FC_TYPE_FCP,
	161	FC_FC_EX_CTX \| FC_FC_LAST_SEQ \| FC_FC_END_SEQ, 0);
	162
	163	lport->tt.seq_send(lport, cmd->seq, fp);
	164	lport->tt.exch_done(cmd->seq);
	165	return 0;
	166	}
	167
	168	int ft_write_pending_status(struct se_cmd *se_cmd)
	169	{
	170	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	171
	172	return cmd->write_data_len != se_cmd->data_length;
	173	}
174
175	/*
176	* Send TX_RDY (transfer ready).
177	*/
178	int ft_write_pending(struct se_cmd *se_cmd)
179	{
180	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
181	struct fc_frame *fp;
182	struct fcp_txrdy *txrdy;
183	struct fc_lport *lport;
184	struct fc_exch *ep;
185	struct fc_frame_header *fh;
186	u32 f_ctl;
187
188	ft_dump_cmd(cmd, __func__);
189
190	ep = fc_seq_exch(cmd->seq);
191	lport = ep->lp;
192	fp = fc_frame_alloc(lport, sizeof(*txrdy));
193	if (!fp)
03e98c9e	194	return -ENOMEM; /* Signal QUEUE_FULL */
3699d92a KP	195
	196	txrdy = fc_frame_payload_get(fp, sizeof(*txrdy));
	197	memset(txrdy, 0, sizeof(*txrdy));
	198	txrdy->ft_burst_len = htonl(se_cmd->data_length);
	199
	200	cmd->seq = lport->tt.seq_start_next(cmd->seq);
	201	fc_fill_fc_hdr(fp, FC_RCTL_DD_DATA_DESC, ep->did, ep->sid, FC_TYPE_FCP,
	202	FC_FC_EX_CTX \| FC_FC_END_SEQ \| FC_FC_SEQ_INIT, 0);
	203
	204	fh = fc_frame_header_get(fp);
	205	f_ctl = ntoh24(fh->fh_f_ctl);
	206
	207	/* Only if it is 'Exchange Responder' */
	208	if (f_ctl & FC_FC_EX_CTX) {
	209	/* Target is 'exchange responder' and sending XFER_READY
	210	* to 'exchange initiator (initiator)'
	211	*/
	212	if ((ep->xid <= lport->lro_xid) &&
	213	(fh->fh_r_ctl == FC_RCTL_DD_DATA_DESC)) {
	214	if (se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
	215	/*
ec98f782 AG	216	* cmd may have been broken up into multiple
	217	* tasks. Link their sgs together so we can
	218	* operate on them all at once.
3699d92a KP	219	*/
3699d92a KP	220	transport_do_task_sg_chain(se_cmd);
a1d8b49a	221	cmd->sg = se_cmd->t_tasks_sg_chained;
3699d92a	222	cmd->sg_cnt =
a1d8b49a	223	se_cmd->t_tasks_sg_chained_no;
3699d92a	224	}
33dc362b YZ	225	if (cmd->sg && lport->tt.ddp_target(lport, ep->xid,
	226	cmd->sg,
	227	cmd->sg_cnt))
3699d92a KP	228	cmd->was_ddp_setup = 1;
	229	}
	230	}
	231	lport->tt.seq_send(lport, cmd->seq, fp);
	232	return 0;
	233	}
	234
	235	u32 ft_get_task_tag(struct se_cmd *se_cmd)
	236	{
	237	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	238
	239	return fc_seq_exch(cmd->seq)->rxid;
	240	}
	241
	242	int ft_get_cmd_state(struct se_cmd *se_cmd)
	243	{
58fc73d1	244	return 0;
3699d92a KP	245	}
3699d92a KP	246
3699d92a KP	247	/*
	248	* FC sequence response handler for follow-on sequences (data) and aborts.
	249	*/
	250	static void ft_recv_seq(struct fc_seq sp, struct fc_frame fp, void *arg)
	251	{
	252	struct ft_cmd *cmd = arg;
	253	struct fc_frame_header *fh;
	254
	255	if (IS_ERR(fp)) {
	256	/* XXX need to find cmd if queued */
3699d92a	257	cmd->seq = NULL;
82f1c8a4	258	transport_generic_free_cmd(&cmd->se_cmd, 0);
3699d92a KP	259	return;
	260	}
	261
	262	fh = fc_frame_header_get(fp);
	263
	264	switch (fh->fh_r_ctl) {
	265	case FC_RCTL_DD_SOL_DATA: /* write data */
	266	ft_recv_write_data(cmd, fp);
	267	break;
	268	case FC_RCTL_DD_UNSOL_CTL: /* command */
	269	case FC_RCTL_DD_SOL_CTL: /* transfer ready */
	270	case FC_RCTL_DD_DATA_DESC: /* transfer ready */
	271	default:
6708bb27	272	pr_debug("%s: unhandled frame r_ctl %x\n",
3699d92a	273	__func__, fh->fh_r_ctl);
dcd998cc	274	ft_invl_hw_context(cmd);
3699d92a	275	fc_frame_free(fp);
82f1c8a4	276	transport_generic_free_cmd(&cmd->se_cmd, 0);
3699d92a KP	277	break;
	278	}
	279	}
	280
	281	/*
	282	* Send a FCP response including SCSI status and optional FCP rsp_code.
	283	* status is SAM_STAT_GOOD (zero) iff code is valid.
	284	* This is used in error cases, such as allocation failures.
	285	*/
	286	static void ft_send_resp_status(struct fc_lport *lport,
	287	const struct fc_frame *rx_fp,
	288	u32 status, enum fcp_resp_rsp_codes code)
	289	{
	290	struct fc_frame *fp;
	291	struct fc_seq *sp;
	292	const struct fc_frame_header *fh;
	293	size_t len;
	294	struct fcp_resp_with_ext *fcp;
	295	struct fcp_resp_rsp_info *info;
	296
	297	fh = fc_frame_header_get(rx_fp);
6708bb27	298	pr_debug("FCP error response: did %x oxid %x status %x code %x\n",
3699d92a KP	299	ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
	300	len = sizeof(*fcp);
	301	if (status == SAM_STAT_GOOD)
	302	len += sizeof(*info);
	303	fp = fc_frame_alloc(lport, len);
	304	if (!fp)
	305	return;
	306	fcp = fc_frame_payload_get(fp, len);
	307	memset(fcp, 0, len);
	308	fcp->resp.fr_status = status;
	309	if (status == SAM_STAT_GOOD) {
	310	fcp->ext.fr_rsp_len = htonl(sizeof(*info));
	311	fcp->resp.fr_flags \|= FCP_RSP_LEN_VAL;
	312	info = (struct fcp_resp_rsp_info *)(fcp + 1);
	313	info->rsp_code = code;
	314	}
	315
	316	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
	317	sp = fr_seq(fp);
	318	if (sp)
	319	lport->tt.seq_send(lport, sp, fp);
	320	else
	321	lport->tt.frame_send(lport, fp);
	322	}
	323
	324	/*
	325	* Send error or task management response.
3699d92a	326	*/
f2f7b09c KP	327	static void ft_send_resp_code(struct ft_cmd *cmd,
f2f7b09c KP	328	enum fcp_resp_rsp_codes code)
3699d92a KP	329	{
	330	ft_send_resp_status(cmd->sess->tport->lport,
	331	cmd->req_frame, SAM_STAT_GOOD, code);
f2f7b09c KP	332	}
	333
	334
	335	/*
	336	* Send error or task management response.
	337	* Always frees the cmd and associated state.
	338	*/
	339	static void ft_send_resp_code_and_free(struct ft_cmd *cmd,
	340	enum fcp_resp_rsp_codes code)
	341	{
	342	ft_send_resp_code(cmd, code);
3699d92a KP	343	ft_free_cmd(cmd);
	344	}
	345
	346	/*
	347	* Handle Task Management Request.
	348	*/
	349	static void ft_send_tm(struct ft_cmd *cmd)
	350	{
3699d92a	351	struct fcp_cmnd *fcp;
00ad4c4e	352	int rc;
3699d92a KP	353	u8 tm_func;
	354
	355	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
	356
	357	switch (fcp->fc_tm_flags) {
	358	case FCP_TMF_LUN_RESET:
	359	tm_func = TMR_LUN_RESET;
3699d92a KP	360	break;
	361	case FCP_TMF_TGT_RESET:
	362	tm_func = TMR_TARGET_WARM_RESET;
	363	break;
	364	case FCP_TMF_CLR_TASK_SET:
	365	tm_func = TMR_CLEAR_TASK_SET;
	366	break;
	367	case FCP_TMF_ABT_TASK_SET:
	368	tm_func = TMR_ABORT_TASK_SET;
	369	break;
	370	case FCP_TMF_CLR_ACA:
	371	tm_func = TMR_CLEAR_ACA;
	372	break;
	373	default:
	374	/*
	375	* FCP4r01 indicates having a combination of
	376	* tm_flags set is invalid.
	377	*/
6708bb27	378	pr_debug("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
f2f7b09c	379	ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
3699d92a KP	380	return;
	381	}
	382
c0974f89	383	/* FIXME: Add referenced task tag for ABORT_TASK */
00ad4c4e	384	rc = target_submit_tmr(&cmd->se_cmd, cmd->sess->se_sess,
59dcb5ec	385	&cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
c0974f89	386	cmd, tm_func, GFP_KERNEL, 0, 0);
00ad4c4e NB	387	if (rc < 0)
00ad4c4e NB	388	ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
3699d92a KP	389	}
	390
	391	/*
	392	* Send status from completed task management request.
	393	*/
	394	int ft_queue_tm_resp(struct se_cmd *se_cmd)
	395	{
	396	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	397	struct se_tmr_req *tmr = se_cmd->se_tmr_req;
	398	enum fcp_resp_rsp_codes code;
	399
	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	*/
35b2cdc4	546	target_submit_cmd(&cmd->se_cmd, cmd->sess->se_sess, fcp->fc_cdb,
e35fa8c2	547	&cmd->ft_sense_buffer[0], scsilun_to_int(&fcp->fc_lun),
0dccb69d	548	ntohl(fcp->fc_dl), task_attr, data_dir, 0);
1edcdb49	549	pr_debug("r_ctl %x alloc target_submit_cmd\n", fh->fh_r_ctl);
3699d92a KP	550	return;
	551
	552	err:
f2f7b09c	553	ft_send_resp_code_and_free(cmd, FCP_CMND_FIELDS_INVALID);
3699d92a	554	}