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Commit 94700877 authored by Michael Cyr's avatar Michael Cyr Committed by Greg Kroah-Hartman
Browse files

scsi: ibmvscsis: Synchronize cmds at tpg_enable_store time 



[ Upstream commit c9b3379f60a83288a5e2f8ea75476460978689b0 ]

This patch changes the way the IBM vSCSI server driver manages its
Command/Response Queue (CRQ).  We used to register the CRQ with phyp at
probe time.  Now we wait until tpg_enable_store.  Similarly, when
tpg_enable_store is called to "disable" (i.e. the stored value is 0),
we unregister the queue with phyp.

One consquence to this is that we have no need for the PART_UP_WAIT_ENAB
state, since we can't get an Init Message from the client in our CRQ if
we're waiting to be enabled, since we haven't registered the queue yet.

Signed-off-by: default avatarMichael Cyr <mikecyr@us.ibm.com>
Signed-off-by: default avatarBryant G. Ly <bryantly@linux.vnet.ibm.com>
Tested-by: default avatarSteven Royer <seroyer@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarSasha Levin <alexander.levin@verizon.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 189491f8

drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c

+38 −186
Original line number Diff line number Diff line
@@ -62,8 +62,6 @@ static long ibmvscsis_parse_command(struct scsi_info *vscsi, 


static void ibmvscsis_adapter_idle(struct scsi_info *vscsi);



static void ibmvscsis_reset_queue(struct scsi_info *vscsi, uint new_state);



static void ibmvscsis_determine_resid(struct se_cmd *se_cmd,

				      struct srp_rsp *rsp)

{
@@ -418,7 +416,6 @@ static void ibmvscsis_disconnect(struct work_struct *work) 
					       proc_work);

	u16 new_state;

	bool wait_idle = false;

	long rc = ADAPT_SUCCESS;



	spin_lock_bh(&vscsi->intr_lock);

	new_state = vscsi->new_state;
@@ -471,30 +468,12 @@ static void ibmvscsis_disconnect(struct work_struct *work) 
			vscsi->state = new_state;

		break;



	/*

	 * If this is a transition into an error state.

	 * a client is attempting to establish a connection

	 * and has violated the RPA protocol.

	 * There can be nothing pending on the adapter although

	 * there can be requests in the command queue.

	 */

	case WAIT_ENABLED:

	case PART_UP_WAIT_ENAB:

		switch (new_state) {

		/* should never happen */

		case ERR_DISCONNECT:

			vscsi->flags |= RESPONSE_Q_DOWN;

			vscsi->state = new_state;

			vscsi->flags &= ~(SCHEDULE_DISCONNECT |

					  DISCONNECT_SCHEDULED);

			ibmvscsis_free_command_q(vscsi);

			break;

		case ERR_DISCONNECT_RECONNECT:

			ibmvscsis_reset_queue(vscsi, WAIT_ENABLED);

			break;



		/* should never happen */

		case WAIT_IDLE:

			rc = ERROR;

			dev_err(&vscsi->dev, "disconnect: invalid state %d for WAIT_IDLE\n",

				vscsi->state);

			break;
@@ -631,7 +610,6 @@ static void ibmvscsis_post_disconnect(struct scsi_info *vscsi, uint new_state, 
			break;



		case WAIT_ENABLED:

		case PART_UP_WAIT_ENAB:

		case WAIT_IDLE:

		case WAIT_CONNECTION:

		case CONNECTED:
@@ -676,7 +654,6 @@ static long ibmvscsis_handle_init_compl_msg(struct scsi_info *vscsi) 
	case SRP_PROCESSING:

	case CONNECTED:

	case WAIT_ENABLED:

	case PART_UP_WAIT_ENAB:

	default:

		rc = ERROR;

		dev_err(&vscsi->dev, "init_msg: invalid state %d to get init compl msg\n",
@@ -699,10 +676,6 @@ static long ibmvscsis_handle_init_msg(struct scsi_info *vscsi) 
	long rc = ADAPT_SUCCESS;



	switch (vscsi->state) {

	case WAIT_ENABLED:

		vscsi->state = PART_UP_WAIT_ENAB;

		break;



	case WAIT_CONNECTION:

		rc = ibmvscsis_send_init_message(vscsi, INIT_COMPLETE_MSG);

		switch (rc) {
@@ -738,7 +711,7 @@ static long ibmvscsis_handle_init_msg(struct scsi_info *vscsi) 
	case UNCONFIGURING:

		break;



	case PART_UP_WAIT_ENAB:

	case WAIT_ENABLED:

	case CONNECTED:

	case SRP_PROCESSING:

	case WAIT_IDLE:
@@ -801,11 +774,10 @@ static long ibmvscsis_init_msg(struct scsi_info *vscsi, struct viosrp_crq *crq) 
/**

 * ibmvscsis_establish_new_q() - Establish new CRQ queue

 * @vscsi:	Pointer to our adapter structure

 * @new_state:	New state being established after resetting the queue

 *

 * Must be called with interrupt lock held.

 */

static long ibmvscsis_establish_new_q(struct scsi_info *vscsi, uint new_state)

static long ibmvscsis_establish_new_q(struct scsi_info *vscsi)

{

	long rc = ADAPT_SUCCESS;

	uint format;
@@ -817,19 +789,19 @@ static long ibmvscsis_establish_new_q(struct scsi_info *vscsi, uint new_state) 


	rc = vio_enable_interrupts(vscsi->dma_dev);

	if (rc) {

		pr_warn("reset_queue: failed to enable interrupts, rc %ld\n",

		pr_warn("establish_new_q: failed to enable interrupts, rc %ld\n",

			rc);

		return rc;

	}



	rc = ibmvscsis_check_init_msg(vscsi, &format);

	if (rc) {

		dev_err(&vscsi->dev, "reset_queue: check_init_msg failed, rc %ld\n",

		dev_err(&vscsi->dev, "establish_new_q: check_init_msg failed, rc %ld\n",

			rc);

		return rc;

	}



	if (format == UNUSED_FORMAT && new_state == WAIT_CONNECTION) {

	if (format == UNUSED_FORMAT) {

		rc = ibmvscsis_send_init_message(vscsi, INIT_MSG);

		switch (rc) {

		case H_SUCCESS:
@@ -847,6 +819,8 @@ static long ibmvscsis_establish_new_q(struct scsi_info *vscsi, uint new_state) 
			rc = H_HARDWARE;

			break;

		}

	} else if (format == INIT_MSG) {

		rc = ibmvscsis_handle_init_msg(vscsi);

	}



	return rc;
@@ -855,7 +829,6 @@ static long ibmvscsis_establish_new_q(struct scsi_info *vscsi, uint new_state) 
/**

 * ibmvscsis_reset_queue() - Reset CRQ Queue

 * @vscsi:	Pointer to our adapter structure

 * @new_state:	New state to establish after resetting the queue

 *

 * This function calls h_free_q and then calls h_reg_q and does all

 * of the bookkeeping to get us back to where we can communicate.
@@ -872,7 +845,7 @@ static long ibmvscsis_establish_new_q(struct scsi_info *vscsi, uint new_state) 
 * EXECUTION ENVIRONMENT:

 *	Process environment, called with interrupt lock held

 */

static void ibmvscsis_reset_queue(struct scsi_info *vscsi, uint new_state)

static void ibmvscsis_reset_queue(struct scsi_info *vscsi)

{

	int bytes;

	long rc = ADAPT_SUCCESS;
@@ -885,19 +858,18 @@ static void ibmvscsis_reset_queue(struct scsi_info *vscsi, uint new_state) 
		vscsi->rsp_q_timer.timer_pops = 0;

		vscsi->debit = 0;

		vscsi->credit = 0;

		vscsi->state = new_state;

		vscsi->state = WAIT_CONNECTION;

		vio_enable_interrupts(vscsi->dma_dev);

	} else {

		rc = ibmvscsis_free_command_q(vscsi);

		if (rc == ADAPT_SUCCESS) {

			vscsi->state = new_state;

			vscsi->state = WAIT_CONNECTION;



			bytes = vscsi->cmd_q.size * PAGE_SIZE;

			rc = h_reg_crq(vscsi->dds.unit_id,

				       vscsi->cmd_q.crq_token, bytes);

			if (rc == H_CLOSED || rc == H_SUCCESS) {

				rc = ibmvscsis_establish_new_q(vscsi,

							       new_state);

				rc = ibmvscsis_establish_new_q(vscsi);

			}



			if (rc != ADAPT_SUCCESS) {
@@ -1016,10 +988,6 @@ static long ibmvscsis_trans_event(struct scsi_info *vscsi, 
						   TRANS_EVENT));

			break;



		case PART_UP_WAIT_ENAB:

			vscsi->state = WAIT_ENABLED;

			break;



		case SRP_PROCESSING:

			if ((vscsi->debit > 0) ||

			    !list_empty(&vscsi->schedule_q) ||
@@ -1220,15 +1188,18 @@ static void ibmvscsis_adapter_idle(struct scsi_info *vscsi) 


	switch (vscsi->state) {

	case ERR_DISCONNECT_RECONNECT:

		ibmvscsis_reset_queue(vscsi, WAIT_CONNECTION);

		ibmvscsis_reset_queue(vscsi);

		pr_debug("adapter_idle, disc_rec: flags 0x%x\n", vscsi->flags);

		break;



	case ERR_DISCONNECT:

		ibmvscsis_free_command_q(vscsi);

		vscsi->flags &= ~DISCONNECT_SCHEDULED;

		vscsi->flags &= ~(SCHEDULE_DISCONNECT | DISCONNECT_SCHEDULED);

		vscsi->flags |= RESPONSE_Q_DOWN;

		if (vscsi->tport.enabled)

			vscsi->state = ERR_DISCONNECTED;

		else

			vscsi->state = WAIT_ENABLED;

		pr_debug("adapter_idle, disc: flags 0x%x, state 0x%hx\n",

			 vscsi->flags, vscsi->state);

		break;
@@ -1773,8 +1744,8 @@ static void ibmvscsis_send_messages(struct scsi_info *vscsi) 
					be64_to_cpu(msg_hi),

					be64_to_cpu(cmd->rsp.tag));



			pr_debug("send_messages: tag 0x%llx, rc %ld\n",

				 be64_to_cpu(cmd->rsp.tag), rc);

			pr_debug("send_messages: cmd %p, tag 0x%llx, rc %ld\n",

				 cmd, be64_to_cpu(cmd->rsp.tag), rc);



			/* if all ok free up the command element resources */

			if (rc == H_SUCCESS) {
@@ -2787,36 +2758,6 @@ static irqreturn_t ibmvscsis_interrupt(int dummy, void *data) 
	return IRQ_HANDLED;

}



/**

 * ibmvscsis_check_q() - Helper function to Check Init Message Valid

 * @vscsi:	Pointer to our adapter structure

 *

 * Checks if a initialize message was queued by the initiatior

 * while the timing window was open.  This function is called from

 * probe after the CRQ is created and interrupts are enabled.

 * It would only be used by adapters who wait for some event before

 * completing the init handshake with the client.  For ibmvscsi, this

 * event is waiting for the port to be enabled.

 *

 * EXECUTION ENVIRONMENT:

 *	Process level only, interrupt lock held

 */

static long ibmvscsis_check_q(struct scsi_info *vscsi)

{

	uint format;

	long rc;



	rc = ibmvscsis_check_init_msg(vscsi, &format);

	if (rc)

		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT_RECONNECT, 0);

	else if (format == UNUSED_FORMAT)

		vscsi->state = WAIT_ENABLED;

	else

		vscsi->state = PART_UP_WAIT_ENAB;



	return rc;

}



/**

 * ibmvscsis_enable_change_state() - Set new state based on enabled status

 * @vscsi:	Pointer to our adapter structure
@@ -2828,77 +2769,19 @@ static long ibmvscsis_check_q(struct scsi_info *vscsi) 
 */

static long ibmvscsis_enable_change_state(struct scsi_info *vscsi)

{

	int bytes;

	long rc = ADAPT_SUCCESS;



handle_state_change:

	switch (vscsi->state) {

	case WAIT_ENABLED:

		rc = ibmvscsis_send_init_message(vscsi, INIT_MSG);

		switch (rc) {

		case H_SUCCESS:

		case H_DROPPED:

		case H_CLOSED:

	bytes = vscsi->cmd_q.size * PAGE_SIZE;

	rc = h_reg_crq(vscsi->dds.unit_id, vscsi->cmd_q.crq_token, bytes);

	if (rc == H_CLOSED || rc == H_SUCCESS) {

		vscsi->state = WAIT_CONNECTION;

			rc = ADAPT_SUCCESS;

			break;



		case H_PARAMETER:

			break;



		case H_HARDWARE:

			break;



		default:

			vscsi->state = UNDEFINED;

			rc = H_HARDWARE;

			break;

		}

		break;

	case PART_UP_WAIT_ENAB:

		rc = ibmvscsis_send_init_message(vscsi, INIT_COMPLETE_MSG);

		switch (rc) {

		case H_SUCCESS:

			vscsi->state = CONNECTED;

			rc = ADAPT_SUCCESS;

			break;



		case H_DROPPED:

		case H_CLOSED:

			vscsi->state = WAIT_ENABLED;

			goto handle_state_change;



		case H_PARAMETER:

			break;



		case H_HARDWARE:

			break;



		default:

			rc = H_HARDWARE;

			break;

		rc = ibmvscsis_establish_new_q(vscsi);

	}

		break;



	case WAIT_CONNECTION:

	case WAIT_IDLE:

	case SRP_PROCESSING:

	case CONNECTED:

		rc = ADAPT_SUCCESS;

		break;

		/* should not be able to get here */

	case UNCONFIGURING:

		rc = ERROR;

		vscsi->state = UNDEFINED;

		break;



		/* driver should never allow this to happen */

	case ERR_DISCONNECT:

	case ERR_DISCONNECT_RECONNECT:

	default:

		dev_err(&vscsi->dev, "in invalid state %d during enable_change_state\n",

			vscsi->state);

		rc = ADAPT_SUCCESS;

		break;

	if (rc != ADAPT_SUCCESS) {

		vscsi->state = ERR_DISCONNECTED;

		vscsi->flags |= RESPONSE_Q_DOWN;

	}



	return rc;
@@ -2918,7 +2801,6 @@ static long ibmvscsis_enable_change_state(struct scsi_info *vscsi) 
 */

static long ibmvscsis_create_command_q(struct scsi_info *vscsi, int num_cmds)

{

	long rc = 0;

	int pages;

	struct vio_dev *vdev = vscsi->dma_dev;
@@ -2942,22 +2824,7 @@ static long ibmvscsis_create_command_q(struct scsi_info *vscsi, int num_cmds) 
		return -ENOMEM;

	}



	rc =  h_reg_crq(vscsi->dds.unit_id, vscsi->cmd_q.crq_token, PAGE_SIZE);

	if (rc) {

		if (rc == H_CLOSED) {

			vscsi->state = WAIT_ENABLED;

			rc = 0;

		} else {

			dma_unmap_single(&vdev->dev, vscsi->cmd_q.crq_token,

					 PAGE_SIZE, DMA_BIDIRECTIONAL);

			free_page((unsigned long)vscsi->cmd_q.base_addr);

			rc = -ENODEV;

		}

	} else {

		vscsi->state = WAIT_ENABLED;

	}



	return rc;

	return 0;

}



/**
@@ -3491,31 +3358,12 @@ static int ibmvscsis_probe(struct vio_dev *vdev, 
		goto destroy_WQ;

	}



	spin_lock_bh(&vscsi->intr_lock);

	vio_enable_interrupts(vdev);

	if (rc) {

		dev_err(&vscsi->dev, "enabling interrupts failed, rc %d\n", rc);

		rc = -ENODEV;

		spin_unlock_bh(&vscsi->intr_lock);

		goto free_irq;

	}



	if (ibmvscsis_check_q(vscsi)) {

		rc = ERROR;

		dev_err(&vscsi->dev, "probe: check_q failed, rc %d\n", rc);

		spin_unlock_bh(&vscsi->intr_lock);

		goto disable_interrupt;

	}

	spin_unlock_bh(&vscsi->intr_lock);

	vscsi->state = WAIT_ENABLED;



	dev_set_drvdata(&vdev->dev, vscsi);



	return 0;



disable_interrupt:

	vio_disable_interrupts(vdev);

free_irq:

	free_irq(vdev->irq, vscsi);

destroy_WQ:

	destroy_workqueue(vscsi->work_q);

unmap_buf:
@@ -3909,18 +3757,22 @@ static ssize_t ibmvscsis_tpg_enable_store(struct config_item *item, 
	}



	if (tmp) {

		tport->enabled = true;

		spin_lock_bh(&vscsi->intr_lock);

		tport->enabled = true;

		lrc = ibmvscsis_enable_change_state(vscsi);

		if (lrc)

			pr_err("enable_change_state failed, rc %ld state %d\n",

			       lrc, vscsi->state);

		spin_unlock_bh(&vscsi->intr_lock);

	} else {

		spin_lock_bh(&vscsi->intr_lock);

		tport->enabled = false;

		/* This simulates the server going down */

		ibmvscsis_post_disconnect(vscsi, ERR_DISCONNECT, 0);

		spin_unlock_bh(&vscsi->intr_lock);

	}



	pr_debug("tpg_enable_store, state %d\n", vscsi->state);

	pr_debug("tpg_enable_store, tmp %ld, state %d\n", tmp, vscsi->state);



	return count;

}

drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h

+0 −2
Original line number Diff line number Diff line
@@ -204,8 +204,6 @@ struct scsi_info { 
	struct list_head waiting_rsp;

#define NO_QUEUE                    0x00

#define WAIT_ENABLED                0X01

	/* driver has received an initialize command */

#define PART_UP_WAIT_ENAB           0x02

#define WAIT_CONNECTION             0x04

	/* have established a connection */

#define CONNECTED                   0x08