[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_base.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 se_mem *mem;

	if (!(ft_debug_logging & FT_DEBUG_IO))
		return;

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

	printk(KERN_INFO "%s: cmd %p se_num %u buf %p len %u se_cmd_flags <0x%x>\n",
	       caller, cmd, se_cmd->t_tasks_se_num,
	       se_cmd->t_task_buf, se_cmd->data_length, se_cmd->se_cmd_flags);

	list_for_each_entry(mem, &se_cmd->t_mem_list, se_list)
		printk(KERN_INFO "%s: cmd %p mem %p page %p "
		       "len 0x%x off 0x%x\n",
		       caller, cmd, mem,
		       mem->se_page, mem->se_len, mem->se_off);
	sp = cmd->seq;
	if (sp) {
		ep = fc_seq_exch(sp);
		printk(KERN_INFO "%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 se_queue_obj *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);
	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
	atomic_inc(&qobj->queue_cnt);
	wake_up_interruptible(&qobj->thread_wq);
}

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, 1, 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) {
				/*
				 * Map se_mem list to scatterlist, so that
				 * DDP can be setup. DDP setup function require
				 * scatterlist. se_mem_list is internal to
				 * TCM/LIO target
				 */
				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_setup(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, 1, 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:
		printk(KERN_INFO "%s: unhandled frame r_ctl %x\n",
		       __func__, fh->fh_r_ctl);
		fc_frame_free(fp);
		transport_generic_free_cmd(&cmd->se_cmd, 0, 1, 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);
	FT_IO_DBG("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.
 * Always frees the cmd and associated state.
 */
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);
	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.
		 */
		FT_TM_DBG("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
		ft_send_resp_code(cmd, FCP_CMND_FIELDS_INVALID);
		return;
	}

	FT_TM_DBG("alloc tm cmd fn %d\n", tm_func);
	tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func);
	if (!tmr) {
		FT_TM_DBG("alloc failed\n");
		ft_send_resp_code(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"
			 */
			FT_TM_DBG("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, 1, 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;
	}
	FT_TM_DBG("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:
	FT_IO_DBG("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:
		printk(KERN_INFO "%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);

	FT_IO_DBG("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, 1, 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, 1, 0);
		return;
	}
	transport_generic_handle_cdb(se_cmd);
	return;

err:
	ft_send_resp_code(cmd, FCP_CMND_FIELDS_INVALID);
}

/*
 * Handle request in the command thread.
 */
static void ft_exec_req(struct ft_cmd *cmd)
{
	FT_IO_DBG("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;
	int ret;

	set_user_nice(current, -20);

	while (!kthread_should_stop()) {
		ret = wait_event_interruptible(qobj->thread_wq,
			atomic_read(&qobj->queue_cnt) || kthread_should_stop());
		if (ret < 0 || 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>
	48	#include <target/target_core_base.h>
	49	#include <target/target_core_tmr.h>
	50	#include <target/configfs_macros.h>
	51
	52	#include "tcm_fc.h"
	53
	54	/*
	55	* Dump cmd state for debugging.
	56	*/
	57	void ft_dump_cmd(struct ft_cmd cmd, const char caller)
	58	{
	59	struct fc_exch *ep;
	60	struct fc_seq *sp;
	61	struct se_cmd *se_cmd;
	62	struct se_mem *mem;
3699d92a KP	63
	64	if (!(ft_debug_logging & FT_DEBUG_IO))
	65	return;
	66
	67	se_cmd = &cmd->se_cmd;
	68	printk(KERN_INFO "%s: cmd %p state %d sess %p seq %p se_cmd %p\n",
	69	caller, cmd, cmd->state, cmd->sess, cmd->seq, se_cmd);
	70	printk(KERN_INFO "%s: cmd %p cdb %p\n",
	71	caller, cmd, cmd->cdb);
	72	printk(KERN_INFO "%s: cmd %p lun %d\n", caller, cmd, cmd->lun);
	73
a1d8b49a AG	74	printk(KERN_INFO "%s: cmd %p se_num %u buf %p len %u se_cmd_flags <0x%x>\n",
	75	caller, cmd, se_cmd->t_tasks_se_num,
	76	se_cmd->t_task_buf, se_cmd->data_length, se_cmd->se_cmd_flags);
5951146d	77
a1d8b49a	78	list_for_each_entry(mem, &se_cmd->t_mem_list, se_list)
5951146d AG	79	printk(KERN_INFO "%s: cmd %p mem %p page %p "
	80	"len 0x%x off 0x%x\n",
	81	caller, cmd, mem,
	82	mem->se_page, mem->se_len, mem->se_off);
3699d92a KP	83	sp = cmd->seq;
	84	if (sp) {
	85	ep = fc_seq_exch(sp);
	86	printk(KERN_INFO "%s: cmd %p sid %x did %x "
	87	"ox_id %x rx_id %x seq_id %x e_stat %x\n",
	88	caller, cmd, ep->sid, ep->did, ep->oxid, ep->rxid,
	89	sp->id, ep->esb_stat);
	90	}
	91	print_hex_dump(KERN_INFO, "ft_dump_cmd ", DUMP_PREFIX_NONE,
	92	16, 4, cmd->cdb, MAX_COMMAND_SIZE, 0);
	93	}
	94
3699d92a KP	95	static void ft_queue_cmd(struct ft_sess sess, struct ft_cmd cmd)
	96	{
	97	struct se_queue_obj *qobj;
	98	unsigned long flags;
	99
	100	qobj = &sess->tport->tpg->qobj;
	101	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
	102	list_add_tail(&cmd->se_req.qr_list, &qobj->qobj_list);
	103	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
	104	atomic_inc(&qobj->queue_cnt);
	105	wake_up_interruptible(&qobj->thread_wq);
	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	{
	150	transport_generic_free_cmd(se_cmd, 0, 1, 0);
	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	/*
257	* Map se_mem list to scatterlist, so that
258	* DDP can be setup. DDP setup function require
259	* scatterlist. se_mem_list is internal to
260	* TCM/LIO target
261	*/
262	transport_do_task_sg_chain(se_cmd);
a1d8b49a	263	cmd->sg = se_cmd->t_tasks_sg_chained;
3699d92a	264	cmd->sg_cnt =
a1d8b49a	265	se_cmd->t_tasks_sg_chained_no;
3699d92a KP	266	}
	267	if (cmd->sg && lport->tt.ddp_setup(lport, ep->xid,
	268	cmd->sg, cmd->sg_cnt))
	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;
	307	transport_generic_free_cmd(&cmd->se_cmd, 0, 1, 0);
	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:
	321	printk(KERN_INFO "%s: unhandled frame r_ctl %x\n",
	322	__func__, fh->fh_r_ctl);
	323	fc_frame_free(fp);
	324	transport_generic_free_cmd(&cmd->se_cmd, 0, 1, 0);
	325	break;
	326	}
	327	}
	328
	329	/*
	330	* Send a FCP response including SCSI status and optional FCP rsp_code.
	331	* status is SAM_STAT_GOOD (zero) iff code is valid.
	332	* This is used in error cases, such as allocation failures.
	333	*/
	334	static void ft_send_resp_status(struct fc_lport *lport,
	335	const struct fc_frame *rx_fp,
	336	u32 status, enum fcp_resp_rsp_codes code)
	337	{
	338	struct fc_frame *fp;
	339	struct fc_seq *sp;
	340	const struct fc_frame_header *fh;
	341	size_t len;
	342	struct fcp_resp_with_ext *fcp;
	343	struct fcp_resp_rsp_info *info;
	344
	345	fh = fc_frame_header_get(rx_fp);
	346	FT_IO_DBG("FCP error response: did %x oxid %x status %x code %x\n",
	347	ntoh24(fh->fh_s_id), ntohs(fh->fh_ox_id), status, code);
	348	len = sizeof(*fcp);
	349	if (status == SAM_STAT_GOOD)
	350	len += sizeof(*info);
	351	fp = fc_frame_alloc(lport, len);
	352	if (!fp)
	353	return;
	354	fcp = fc_frame_payload_get(fp, len);
	355	memset(fcp, 0, len);
	356	fcp->resp.fr_status = status;
	357	if (status == SAM_STAT_GOOD) {
	358	fcp->ext.fr_rsp_len = htonl(sizeof(*info));
359	fcp->resp.fr_flags \|= FCP_RSP_LEN_VAL;
360	info = (struct fcp_resp_rsp_info *)(fcp + 1);
361	info->rsp_code = code;
362	}
363
364	fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_DD_CMD_STATUS, 0);
365	sp = fr_seq(fp);
366	if (sp)
367	lport->tt.seq_send(lport, sp, fp);
368	else
369	lport->tt.frame_send(lport, fp);
370	}
371
372	/*
373	* Send error or task management response.
374	* Always frees the cmd and associated state.
375	*/
376	static void ft_send_resp_code(struct ft_cmd *cmd, enum fcp_resp_rsp_codes code)
377	{
378	ft_send_resp_status(cmd->sess->tport->lport,
379	cmd->req_frame, SAM_STAT_GOOD, code);
380	ft_free_cmd(cmd);
381	}
382
383	/*
384	* Handle Task Management Request.
385	*/
386	static void ft_send_tm(struct ft_cmd *cmd)
387	{
388	struct se_tmr_req *tmr;
389	struct fcp_cmnd *fcp;
61db9527	390	struct ft_sess *sess;
3699d92a KP	391	u8 tm_func;
	392
	393	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
	394
	395	switch (fcp->fc_tm_flags) {
	396	case FCP_TMF_LUN_RESET:
	397	tm_func = TMR_LUN_RESET;
3699d92a KP	398	break;
	399	case FCP_TMF_TGT_RESET:
	400	tm_func = TMR_TARGET_WARM_RESET;
	401	break;
	402	case FCP_TMF_CLR_TASK_SET:
	403	tm_func = TMR_CLEAR_TASK_SET;
	404	break;
	405	case FCP_TMF_ABT_TASK_SET:
	406	tm_func = TMR_ABORT_TASK_SET;
	407	break;
	408	case FCP_TMF_CLR_ACA:
	409	tm_func = TMR_CLEAR_ACA;
	410	break;
	411	default:
	412	/*
	413	* FCP4r01 indicates having a combination of
	414	* tm_flags set is invalid.
	415	*/
	416	FT_TM_DBG("invalid FCP tm_flags %x\n", fcp->fc_tm_flags);
	417	ft_send_resp_code(cmd, FCP_CMND_FIELDS_INVALID);
	418	return;
	419	}
	420
	421	FT_TM_DBG("alloc tm cmd fn %d\n", tm_func);
	422	tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func);
	423	if (!tmr) {
	424	FT_TM_DBG("alloc failed\n");
	425	ft_send_resp_code(cmd, FCP_TMF_FAILED);
	426	return;
	427	}
	428	cmd->se_cmd.se_tmr_req = tmr;
61db9527 KP	429
	430	switch (fcp->fc_tm_flags) {
	431	case FCP_TMF_LUN_RESET:
	432	cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
5951146d	433	if (transport_lookup_tmr_lun(&cmd->se_cmd, cmd->lun) < 0) {
61db9527 KP	434	/*
	435	* Make sure to clean up newly allocated TMR request
	436	* since "unable to handle TMR request because failed
	437	* to get to LUN"
	438	*/
	439	FT_TM_DBG("Failed to get LUN for TMR func %d, "
	440	"se_cmd %p, unpacked_lun %d\n",
	441	tm_func, &cmd->se_cmd, cmd->lun);
	442	ft_dump_cmd(cmd, __func__);
	443	sess = cmd->sess;
	444	transport_send_check_condition_and_sense(&cmd->se_cmd,
	445	cmd->se_cmd.scsi_sense_reason, 0);
	446	transport_generic_free_cmd(&cmd->se_cmd, 0, 1, 0);
	447	ft_sess_put(sess);
	448	return;
	449	}
	450	break;
	451	case FCP_TMF_TGT_RESET:
	452	case FCP_TMF_CLR_TASK_SET:
	453	case FCP_TMF_ABT_TASK_SET:
	454	case FCP_TMF_CLR_ACA:
	455	break;
	456	default:
	457	return;
	458	}
3699d92a KP	459	transport_generic_handle_tmr(&cmd->se_cmd);
	460	}
	461
	462	/*
	463	* Send status from completed task management request.
	464	*/
	465	int ft_queue_tm_resp(struct se_cmd *se_cmd)
	466	{
	467	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
	468	struct se_tmr_req *tmr = se_cmd->se_tmr_req;
	469	enum fcp_resp_rsp_codes code;
	470
	471	switch (tmr->response) {
	472	case TMR_FUNCTION_COMPLETE:
	473	code = FCP_TMF_CMPL;
	474	break;
	475	case TMR_LUN_DOES_NOT_EXIST:
	476	code = FCP_TMF_INVALID_LUN;
	477	break;
	478	case TMR_FUNCTION_REJECTED:
	479	code = FCP_TMF_REJECTED;
	480	break;
	481	case TMR_TASK_DOES_NOT_EXIST:
	482	case TMR_TASK_STILL_ALLEGIANT:
	483	case TMR_TASK_FAILOVER_NOT_SUPPORTED:
	484	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
	485	case TMR_FUNCTION_AUTHORIZATION_FAILED:
	486	default:
	487	code = FCP_TMF_FAILED;
	488	break;
	489	}
	490	FT_TM_DBG("tmr fn %d resp %d fcp code %d\n",
	491	tmr->function, tmr->response, code);
	492	ft_send_resp_code(cmd, code);
	493	return 0;
	494	}
	495
	496	/*
	497	* Handle incoming FCP command.
	498	*/
	499	static void ft_recv_cmd(struct ft_sess sess, struct fc_frame fp)
	500	{
	501	struct ft_cmd *cmd;
	502	struct fc_lport *lport = sess->tport->lport;
	503
	504	cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC);
	505	if (!cmd)
	506	goto busy;
	507	cmd->sess = sess;
	508	cmd->seq = lport->tt.seq_assign(lport, fp);
	509	if (!cmd->seq) {
	510	kfree(cmd);
	511	goto busy;
	512	}
	513	cmd->req_frame = fp; /* hold frame during cmd */
	514	ft_queue_cmd(sess, cmd);
	515	return;
	516
	517	busy:
	518	FT_IO_DBG("cmd or seq allocation failure - sending BUSY\n");
	519	ft_send_resp_status(lport, fp, SAM_STAT_BUSY, 0);
	520	fc_frame_free(fp);
	521	ft_sess_put(sess); /* undo get from lookup */
	522	}
523
524
525	/*
526	* Handle incoming FCP frame.
527	* Caller has verified that the frame is type FCP.
528	*/
529	void ft_recv_req(struct ft_sess sess, struct fc_frame fp)
530	{
531	struct fc_frame_header *fh = fc_frame_header_get(fp);
532
533	switch (fh->fh_r_ctl) {
534	case FC_RCTL_DD_UNSOL_CMD: /* command */
535	ft_recv_cmd(sess, fp);
536	break;
537	case FC_RCTL_DD_SOL_DATA: /* write data */
538	case FC_RCTL_DD_UNSOL_CTL:
539	case FC_RCTL_DD_SOL_CTL:
540	case FC_RCTL_DD_DATA_DESC: /* transfer ready */
541	case FC_RCTL_ELS4_REQ: /* SRR, perhaps */
542	default:
543	printk(KERN_INFO "%s: unhandled frame r_ctl %x\n",
544	__func__, fh->fh_r_ctl);
545	fc_frame_free(fp);
546	ft_sess_put(sess); /* undo get from lookup */
547	break;
548	}
549	}
550
551	/*
552	* Send new command to target.
553	*/
554	static void ft_send_cmd(struct ft_cmd *cmd)
555	{
556	struct fc_frame_header *fh = fc_frame_header_get(cmd->req_frame);
557	struct se_cmd *se_cmd;
558	struct fcp_cmnd *fcp;
559	int data_dir;
560	u32 data_len;
561	int task_attr;
562	int ret;
563
564	fcp = fc_frame_payload_get(cmd->req_frame, sizeof(*fcp));
565	if (!fcp)
566	goto err;
567
568	if (fcp->fc_flags & FCP_CFL_LEN_MASK)
569	goto err; /* not handling longer CDBs yet */
570
571	if (fcp->fc_tm_flags) {
572	task_attr = FCP_PTA_SIMPLE;
573	data_dir = DMA_NONE;
574	data_len = 0;
575	} else {
576	switch (fcp->fc_flags & (FCP_CFL_RDDATA \| FCP_CFL_WRDATA)) {
577	case 0:
578	data_dir = DMA_NONE;
579	break;
580	case FCP_CFL_RDDATA:
581	data_dir = DMA_FROM_DEVICE;
582	break;
583	case FCP_CFL_WRDATA:
584	data_dir = DMA_TO_DEVICE;
585	break;
586	case FCP_CFL_WRDATA \| FCP_CFL_RDDATA:
587	goto err; /* TBD not supported by tcm_fc yet */
588	}
61db1802 NB	589	/*
	590	* Locate the SAM Task Attr from fc_pri_ta
	591	*/
	592	switch (fcp->fc_pri_ta & FCP_PTA_MASK) {
	593	case FCP_PTA_HEADQ:
	594	task_attr = MSG_HEAD_TAG;
	595	break;
	596	case FCP_PTA_ORDERED:
	597	task_attr = MSG_ORDERED_TAG;
	598	break;
	599	case FCP_PTA_ACA:
	600	task_attr = MSG_ACA_TAG;
	601	break;
	602	case FCP_PTA_SIMPLE: /* Fallthrough */
	603	default:
	604	task_attr = MSG_SIMPLE_TAG;
	605	}
	606
3699d92a	607
3699d92a KP	608	task_attr = fcp->fc_pri_ta & FCP_PTA_MASK;
	609	data_len = ntohl(fcp->fc_dl);
	610	cmd->cdb = fcp->fc_cdb;
	611	}
	612
	613	se_cmd = &cmd->se_cmd;
	614	/*
	615	* Initialize struct se_cmd descriptor from target_core_mod
	616	* infrastructure
	617	*/
	618	transport_init_se_cmd(se_cmd, &ft_configfs->tf_ops, cmd->sess->se_sess,
	619	data_len, data_dir, task_attr,
	620	&cmd->ft_sense_buffer[0]);
	621	/*
	622	* Check for FCP task management flags
	623	*/
	624	if (fcp->fc_tm_flags) {
	625	ft_send_tm(cmd);
	626	return;
	627	}
	628
	629	fc_seq_exch(cmd->seq)->lp->tt.seq_set_resp(cmd->seq, ft_recv_seq, cmd);
	630
61db9527	631	cmd->lun = scsilun_to_int((struct scsi_lun *)fcp->fc_lun);
5951146d	632	ret = transport_lookup_cmd_lun(&cmd->se_cmd, cmd->lun);
3699d92a KP	633	if (ret < 0) {
	634	ft_dump_cmd(cmd, __func__);
	635	transport_send_check_condition_and_sense(&cmd->se_cmd,
	636	cmd->se_cmd.scsi_sense_reason, 0);
	637	return;
	638	}
	639
	640	ret = transport_generic_allocate_tasks(se_cmd, cmd->cdb);
	641
	642	FT_IO_DBG("r_ctl %x alloc task ret %d\n", fh->fh_r_ctl, ret);
	643	ft_dump_cmd(cmd, __func__);
	644
5951146d	645	if (ret == -ENOMEM) {
3699d92a KP	646	transport_send_check_condition_and_sense(se_cmd,
	647	TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
	648	transport_generic_free_cmd(se_cmd, 0, 1, 0);
	649	return;
	650	}
5951146d	651	if (ret == -EINVAL) {
3699d92a KP	652	if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
	653	ft_queue_status(se_cmd);
	654	else
	655	transport_send_check_condition_and_sense(se_cmd,
	656	se_cmd->scsi_sense_reason, 0);
	657	transport_generic_free_cmd(se_cmd, 0, 1, 0);
	658	return;
	659	}
	660	transport_generic_handle_cdb(se_cmd);
	661	return;
	662
	663	err:
	664	ft_send_resp_code(cmd, FCP_CMND_FIELDS_INVALID);
3699d92a KP	665	}
	666
	667	/*
	668	* Handle request in the command thread.
	669	*/
	670	static void ft_exec_req(struct ft_cmd *cmd)
	671	{
	672	FT_IO_DBG("cmd state %x\n", cmd->state);
	673	switch (cmd->state) {
	674	case FC_CMD_ST_NEW:
	675	ft_send_cmd(cmd);
	676	break;
	677	default:
	678	break;
	679	}
	680	}
	681
	682	/*
	683	* Processing thread.
	684	* Currently one thread per tpg.
	685	*/
	686	int ft_thread(void *arg)
	687	{
	688	struct ft_tpg *tpg = arg;
	689	struct se_queue_obj *qobj = &tpg->qobj;
	690	struct ft_cmd *cmd;
	691	int ret;
	692
	693	set_user_nice(current, -20);
	694
	695	while (!kthread_should_stop()) {
	696	ret = wait_event_interruptible(qobj->thread_wq,
	697	atomic_read(&qobj->queue_cnt) \|\| kthread_should_stop());
	698	if (ret < 0 \|\| kthread_should_stop())
	699	goto out;
	700	cmd = ft_dequeue_cmd(qobj);
	701	if (cmd)
	702	ft_exec_req(cmd);
	703	}
	704
	705	out:
	706	return 0;
	707	}