[PATCH] fix megaraid.c locking

This fixes locking in megaraid.c, namely:

 (1) make sure megaraid_queue release the adapter lock by changing the
     code to have a single return
 (2) remove the errornous scsi_assign_lock call

Testing by Burton Windle.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Burton Windle <bwindle@fint.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/scsi/megaraid.c b/drivers/scsi/megaraid.c
index dfea346b00a559975cc83853bafbf4f59dbcebd9..f9792528e33fb473d7e03314d5318b4aa0863ef9 100644 (file)
--- a/drivers/scsi/megaraid.c
+++ b/drivers/scsi/megaraid.c
@@ -380,23 +380,23 @@ megaraid_queue(Scsi_Cmnd *scmd, void (*done)(Scsi_Cmnd *))
 
        spin_lock_irqsave(&adapter->lock, flags);
        scb = mega_build_cmd(adapter, scmd, &busy);
+       if (!scb)
+               goto out;
 
-       if(scb) {
-               scb->state |= SCB_PENDQ;
-               list_add_tail(&scb->list, &adapter->pending_list);
+       scb->state |= SCB_PENDQ;
+       list_add_tail(&scb->list, &adapter->pending_list);
 
-               /*
-                * Check if the HBA is in quiescent state, e.g., during a
-                * delete logical drive opertion. If it is, don't run
-                * the pending_list.
-                */
-               if(atomic_read(&adapter->quiescent) == 0) {
-                       mega_runpendq(adapter);
-               }
-               return 0;
-       }
-       spin_unlock_irqrestore(&adapter->lock, flags);
+       /*
+        * Check if the HBA is in quiescent state, e.g., during a
+        * delete logical drive opertion. If it is, don't run
+        * the pending_list.
+        */
+       if (atomic_read(&adapter->quiescent) == 0)
+               mega_runpendq(adapter);
 
+       busy = 0;
+ out:
+       spin_unlock_irqrestore(&adapter->lock, flags);
        return busy;
 }
 
@@ -4677,7 +4677,6 @@ megaraid_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
 
        adapter->flag = flag;
        spin_lock_init(&adapter->lock);
-       scsi_assign_lock(host, &adapter->lock);
 
        host->cmd_per_lun = max_cmd_per_lun;
        host->max_sectors = max_sectors_per_io;