stex: Add hotplug support

1. Add hotplug support. Pegasus support surprise removal. To this end, I
   use return_abnormal_state function to return DID_NO_CONNECT for all
   commands which sent to driver.

2. Remove stex_hba_stop in stex_remove because we cannot send command to
   device after hotplug.

3. Add new device status: MU_STATE_STOP, MU_STATE_NOCONNECT,
   MU_STATE_STOP. MU_STATE_STOP is currently not referenced.
   MU_STATE_NOCONNECT represent that device is plugged out from the
   host.

4. Use return_abnormal_function() to substitute part of code in
   stex_do_reset.

Signed-off-by: Charles Chiou <charles.chiou@tw.promise.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/stex.c b/drivers/scsi/stex.c
index 495d6322bb21713f38afd7f5f154869e016ccd57..19946031fa9af97b73c2e2c16812a7f7385811ef 100644 (file)
--- a/drivers/scsi/stex.c
+++ b/drivers/scsi/stex.c
@@ -84,6 +84,8 @@ enum {
        MU_STATE_STARTED                        = 2,
        MU_STATE_RESETTING                      = 3,
        MU_STATE_FAILED                         = 4,
+       MU_STATE_STOP                           = 5,
+       MU_STATE_NOCONNECT                      = 6,
 
        MU_MAX_DELAY                            = 120,
        MU_HANDSHAKE_SIGNATURE                  = 0x55aaaa55,
@@ -537,6 +539,27 @@ stex_ss_send_cmd(struct st_hba *hba, struct req_msg *req, u16 tag)
        readl(hba->mmio_base + YH2I_REQ); /* flush */
 }
 
+static void return_abnormal_state(struct st_hba *hba, int status)
+{
+       struct st_ccb *ccb;
+       unsigned long flags;
+       u16 tag;
+
+       spin_lock_irqsave(hba->host->host_lock, flags);
+       for (tag = 0; tag < hba->host->can_queue; tag++) {
+               ccb = &hba->ccb[tag];
+               if (ccb->req == NULL)
+                       continue;
+               ccb->req = NULL;
+               if (ccb->cmd) {
+                       scsi_dma_unmap(ccb->cmd);
+                       ccb->cmd->result = status << 16;
+                       ccb->cmd->scsi_done(ccb->cmd);
+                       ccb->cmd = NULL;
+               }
+       }
+       spin_unlock_irqrestore(hba->host->host_lock, flags);
+}
 static int
 stex_slave_config(struct scsi_device *sdev)
 {
@@ -560,8 +583,12 @@ stex_queuecommand_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
        id = cmd->device->id;
        lun = cmd->device->lun;
        hba = (struct st_hba *) &host->hostdata[0];
-
-       if (unlikely(hba->mu_status == MU_STATE_RESETTING))
+       if (hba->mu_status == MU_STATE_NOCONNECT) {
+               cmd->result = DID_NO_CONNECT;
+               done(cmd);
+               return 0;
+       }
+       if (unlikely(hba->mu_status != MU_STATE_STARTED))
                return SCSI_MLQUEUE_HOST_BUSY;
 
        switch (cmd->cmnd[0]) {
@@ -1260,10 +1287,8 @@ static void stex_ss_reset(struct st_hba *hba)
 
 static int stex_do_reset(struct st_hba *hba)
 {
-       struct st_ccb *ccb;
        unsigned long flags;
        unsigned int mu_status = MU_STATE_RESETTING;
-       u16 tag;
 
        spin_lock_irqsave(hba->host->host_lock, flags);
        if (hba->mu_status == MU_STATE_STARTING) {
@@ -1297,20 +1322,8 @@ static int stex_do_reset(struct st_hba *hba)
        else if (hba->cardtype == st_yel)
                stex_ss_reset(hba);
 
-       spin_lock_irqsave(hba->host->host_lock, flags);
-       for (tag = 0; tag < hba->host->can_queue; tag++) {
-               ccb = &hba->ccb[tag];
-               if (ccb->req == NULL)
-                       continue;
-               ccb->req = NULL;
-               if (ccb->cmd) {
-                       scsi_dma_unmap(ccb->cmd);
-                       ccb->cmd->result = DID_RESET << 16;
-                       ccb->cmd->scsi_done(ccb->cmd);
-                       ccb->cmd = NULL;
-               }
-       }
-       spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+       return_abnormal_state(hba, DID_RESET);
 
        if (stex_handshake(hba) == 0)
                return 0;
@@ -1771,9 +1784,11 @@ static void stex_remove(struct pci_dev *pdev)
 {
        struct st_hba *hba = pci_get_drvdata(pdev);
 
+       hba->mu_status = MU_STATE_NOCONNECT;
+       return_abnormal_state(hba, DID_NO_CONNECT);
        scsi_remove_host(hba->host);
 
-       stex_hba_stop(hba);
+       scsi_block_requests(hba->host);
 
        stex_hba_free(hba);