scsi: ibmvscsis: Synchronize cmds at remove time

[ Upstream commit 8bf11557d44d00562360d370de8aa70ba89aa0d5 ]

This patch adds code to disconnect from the client, which will make sure
any outstanding commands have been completed, before continuing on with
the remove operation.

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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
index 504e593f2879a90a4c72f78f1a014f0bd95b7bc6..c4fe95a25621bdd38f5cfedc8d21285ed9f97a7c 100644 (file)
--- a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
+++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
@@ -470,6 +470,18 @@ static void ibmvscsis_disconnect(struct work_struct *work)
 
        case WAIT_ENABLED:
                switch (new_state) {
+               case UNCONFIGURING:
+                       vscsi->state = new_state;
+                       vscsi->flags |= RESPONSE_Q_DOWN;
+                       vscsi->flags &= ~(SCHEDULE_DISCONNECT |
+                                         DISCONNECT_SCHEDULED);
+                       dma_rmb();
+                       if (vscsi->flags & CFG_SLEEPING) {
+                               vscsi->flags &= ~CFG_SLEEPING;
+                               complete(&vscsi->unconfig);
+                       }
+                       break;
+
                /* should never happen */
                case ERR_DISCONNECT:
                case ERR_DISCONNECT_RECONNECT:
@@ -482,6 +494,13 @@ static void ibmvscsis_disconnect(struct work_struct *work)
 
        case WAIT_IDLE:
                switch (new_state) {
+               case UNCONFIGURING:
+                       vscsi->flags |= RESPONSE_Q_DOWN;
+                       vscsi->state = new_state;
+                       vscsi->flags &= ~(SCHEDULE_DISCONNECT |
+                                         DISCONNECT_SCHEDULED);
+                       ibmvscsis_free_command_q(vscsi);
+                       break;
                case ERR_DISCONNECT:
                case ERR_DISCONNECT_RECONNECT:
                        vscsi->state = new_state;
@@ -1187,6 +1206,15 @@ static void ibmvscsis_adapter_idle(struct scsi_info *vscsi)
                free_qs = true;
 
        switch (vscsi->state) {
+       case UNCONFIGURING:
+               ibmvscsis_free_command_q(vscsi);
+               dma_rmb();
+               isync();
+               if (vscsi->flags & CFG_SLEEPING) {
+                       vscsi->flags &= ~CFG_SLEEPING;
+                       complete(&vscsi->unconfig);
+               }
+               break;
        case ERR_DISCONNECT_RECONNECT:
                ibmvscsis_reset_queue(vscsi);
                pr_debug("adapter_idle, disc_rec: flags 0x%x\n", vscsi->flags);
@@ -3342,6 +3370,7 @@ static int ibmvscsis_probe(struct vio_dev *vdev,
                     (unsigned long)vscsi);
 
        init_completion(&vscsi->wait_idle);
+       init_completion(&vscsi->unconfig);
 
        snprintf(wq_name, 24, "ibmvscsis%s", dev_name(&vdev->dev));
        vscsi->work_q = create_workqueue(wq_name);
@@ -3397,10 +3426,11 @@ static int ibmvscsis_remove(struct vio_dev *vdev)
 
        pr_debug("remove (%s)\n", dev_name(&vscsi->dma_dev->dev));
 
-       /*
-        * TBD: Need to handle if there are commands on the waiting_rsp q
-        *      Actually, can there still be cmds outstanding to tcm?
-        */
+       spin_lock_bh(&vscsi->intr_lock);
+       ibmvscsis_post_disconnect(vscsi, UNCONFIGURING, 0);
+       vscsi->flags |= CFG_SLEEPING;
+       spin_unlock_bh(&vscsi->intr_lock);
+       wait_for_completion(&vscsi->unconfig);
 
        vio_disable_interrupts(vdev);
        free_irq(vdev->irq, vscsi);
@@ -3409,7 +3439,6 @@ static int ibmvscsis_remove(struct vio_dev *vdev)
                         DMA_BIDIRECTIONAL);
        kfree(vscsi->map_buf);
        tasklet_kill(&vscsi->work_task);
-       ibmvscsis_unregister_command_q(vscsi);
        ibmvscsis_destroy_command_q(vscsi);
        ibmvscsis_freetimer(vscsi);
        ibmvscsis_free_cmds(vscsi);

diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h
index 17e0ef43c5250896ae14300496f06f6c702b5d0f..98b0ca79a5c5e2e04c526ca741c504377c75ca9e 100644 (file)
--- a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h
+++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.h
@@ -257,6 +257,8 @@ struct scsi_info {
 #define SCHEDULE_DISCONNECT           0x00400
        /* disconnect handler is scheduled */
 #define DISCONNECT_SCHEDULED          0x00800
+       /* remove function is sleeping */
+#define CFG_SLEEPING                  0x01000
        u32 flags;
        /* adapter lock */
        spinlock_t intr_lock;
@@ -285,6 +287,7 @@ struct scsi_info {
 
        struct workqueue_struct *work_q;
        struct completion wait_idle;
+       struct completion unconfig;
        struct device dev;
        struct vio_dev *dma_dev;
        struct srp_target target;