[SCSI] Update the SCSI state model to allow blocking in the created state

[safe/jmp/linux-2.6] / drivers / scsi / scsi_lib.c

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 62307bd..d2884bf 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1251,6 +1251,7 @@ int scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
                        break;
                case SDEV_QUIESCE:
                case SDEV_BLOCK:
+               case SDEV_CREATED_BLOCK:
                        /*
                         * If the devices is blocked we defer normal commands.
                         */
@@ -2064,10 +2065,13 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
 
        switch (state) {
        case SDEV_CREATED:
-               /* There are no legal states that come back to
-                * created.  This is the manually initialised start
-                * state */
-               goto illegal;
+               switch (oldstate) {
+               case SDEV_CREATED_BLOCK:
+                       break;
+               default:
+                       goto illegal;
+               }
+               break;
                        
        case SDEV_RUNNING:
                switch (oldstate) {
@@ -2105,8 +2109,17 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
 
        case SDEV_BLOCK:
                switch (oldstate) {
-               case SDEV_CREATED:
                case SDEV_RUNNING:
+               case SDEV_CREATED_BLOCK:
+                       break;
+               default:
+                       goto illegal;
+               }
+               break;
+
+       case SDEV_CREATED_BLOCK:
+               switch (oldstate) {
+               case SDEV_CREATED:
                        break;
                default:
                        goto illegal;
@@ -2394,8 +2407,12 @@ scsi_internal_device_block(struct scsi_device *sdev)
        int err = 0;
 
        err = scsi_device_set_state(sdev, SDEV_BLOCK);
-       if (err)
-               return err;
+       if (err) {
+               err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK);
+
+               if (err)
+                       return err;
+       }
 
        /* 
         * The device has transitioned to SDEV_BLOCK.  Stop the
@@ -2438,8 +2455,12 @@ scsi_internal_device_unblock(struct scsi_device *sdev)
         * and goose the device queue if successful.  
         */
        err = scsi_device_set_state(sdev, SDEV_RUNNING);
-       if (err)
-               return err;
+       if (err) {
+               err = scsi_device_set_state(sdev, SDEV_CREATED);
+
+               if (err)
+                       return err;
+       }
 
        spin_lock_irqsave(q->queue_lock, flags);
        blk_start_queue(q);