scsi: ibmvscsis: Synchronize cmds at tpg_enable_store time

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: Michael Cyr <mikecyr@us.ibm.com>
Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Tested-by: Steven Royer <seroyer@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Michael Cyr 2016-10-13 11:02:39 -05:00 committed by Martin K. Petersen
parent 79fac9c9b7
commit c9b3379f60
2 changed files with 39 additions and 189 deletions

View File

@ -61,8 +61,6 @@ 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)
{
@ -417,7 +415,6 @@ 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;
@ -470,30 +467,12 @@ 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) {
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 ERR_DISCONNECT:
case ERR_DISCONNECT_RECONNECT:
case WAIT_IDLE:
rc = ERROR;
dev_err(&vscsi->dev, "disconnect: invalid state %d for WAIT_IDLE\n",
vscsi->state);
break;
@ -630,7 +609,6 @@ 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:
@ -675,7 +653,6 @@ 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",
@ -698,10 +675,6 @@ 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) {
@ -737,7 +710,7 @@ 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:
@ -800,11 +773,10 @@ 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;
@ -816,19 +788,19 @@ 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:
@ -846,6 +818,8 @@ 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;
@ -854,7 +828,6 @@ 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.
@ -871,7 +844,7 @@ 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;
@ -884,19 +857,18 @@ 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) {
@ -1015,10 +987,6 @@ 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) ||
@ -1219,15 +1187,18 @@ 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;
@ -1772,8 +1743,8 @@ 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;
rc = ibmvscsis_establish_new_q(vscsi);
}
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;
}
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 @@ handle_state_change:
*/
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;
}
/**
@ -3487,31 +3354,12 @@ 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:
@ -3905,18 +3753,22 @@ 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;
}

View File

@ -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