[SCSI] zfcp: fix bug during adapter shutdown

[safe/jmp/linux-2.6] / drivers / s390 / scsi / zfcp_fsf.c

diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index 21a6d76..56b2ea9 100644 (file)
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -61,7 +61,6 @@ static int zfcp_fsf_fsfstatus_eval(struct zfcp_fsf_req *);
 static int zfcp_fsf_fsfstatus_qual_eval(struct zfcp_fsf_req *);
 static int zfcp_fsf_req_dispatch(struct zfcp_fsf_req *);
 static void zfcp_fsf_req_dismiss(struct zfcp_fsf_req *);
-static void zfcp_fsf_req_free(struct zfcp_fsf_req *);
 
 /* association between FSF command and FSF QTCB type */
 static u32 fsf_qtcb_type[] = {
@@ -149,13 +148,13 @@ zfcp_fsf_req_alloc(mempool_t *pool, int req_flags)
  *
  * locks:       none
  */
-static void
+void
 zfcp_fsf_req_free(struct zfcp_fsf_req *fsf_req)
 {
        if (likely(fsf_req->pool != NULL))
                mempool_free(fsf_req, fsf_req->pool);
-               else
-                       kfree(fsf_req);
+       else
+               kfree(fsf_req);
 }
 
 /*
@@ -170,30 +169,21 @@ zfcp_fsf_req_free(struct zfcp_fsf_req *fsf_req)
 int
 zfcp_fsf_req_dismiss_all(struct zfcp_adapter *adapter)
 {
-       int retval = 0;
        struct zfcp_fsf_req *fsf_req, *tmp;
+       unsigned long flags;
+       LIST_HEAD(remove_queue);
 
-       list_for_each_entry_safe(fsf_req, tmp, &adapter->fsf_req_list_head,
-                                list)
-           zfcp_fsf_req_dismiss(fsf_req);
-       /* wait_event_timeout? */
-       while (!list_empty(&adapter->fsf_req_list_head)) {
-               ZFCP_LOG_DEBUG("fsf req list of adapter %s not yet empty\n",
-                              zfcp_get_busid_by_adapter(adapter));
-               /* wait for woken intiators to clean up their requests */
-               msleep(jiffies_to_msecs(ZFCP_FSFREQ_CLEANUP_TIMEOUT));
-       }
+       spin_lock_irqsave(&adapter->fsf_req_list_lock, flags);
+       list_splice_init(&adapter->fsf_req_list_head, &remove_queue);
+       atomic_set(&adapter->fsf_reqs_active, 0);
+       spin_unlock_irqrestore(&adapter->fsf_req_list_lock, flags);
 
-       /* consistency check */
-       if (atomic_read(&adapter->fsf_reqs_active)) {
-               ZFCP_LOG_NORMAL("bug: There are still %d FSF requests pending "
-                               "on adapter %s after cleanup.\n",
-                               atomic_read(&adapter->fsf_reqs_active),
-                               zfcp_get_busid_by_adapter(adapter));
-               atomic_set(&adapter->fsf_reqs_active, 0);
+       list_for_each_entry_safe(fsf_req, tmp, &remove_queue, list) {
+               list_del(&fsf_req->list);
+               zfcp_fsf_req_dismiss(fsf_req);
        }
 
-       return retval;
+       return 0;
 }
 
 /*
@@ -226,10 +216,6 @@ zfcp_fsf_req_complete(struct zfcp_fsf_req *fsf_req)
 {
        int retval = 0;
        int cleanup;
-       struct zfcp_adapter *adapter = fsf_req->adapter;
-
-       /* do some statistics */
-       atomic_dec(&adapter->fsf_reqs_active);
 
        if (unlikely(fsf_req->fsf_command == FSF_QTCB_UNSOLICITED_STATUS)) {
                ZFCP_LOG_DEBUG("Status read response received\n");
@@ -260,7 +246,7 @@ zfcp_fsf_req_complete(struct zfcp_fsf_req *fsf_req)
                 * lock must not be held here since it will be
                 * grabed by the called routine, too
                 */
-               zfcp_fsf_req_cleanup(fsf_req);
+               zfcp_fsf_req_free(fsf_req);
        } else {
                /* notify initiator waiting for the requests completion */
                ZFCP_LOG_TRACE("waking initiator of FSF request %p\n",fsf_req);
@@ -936,7 +922,7 @@ zfcp_fsf_status_read_handler(struct zfcp_fsf_req *fsf_req)
 
        if (fsf_req->status & ZFCP_STATUS_FSFREQ_DISMISSED) {
                mempool_free(status_buffer, adapter->pool.data_status_read);
-               zfcp_fsf_req_cleanup(fsf_req);
+               zfcp_fsf_req_free(fsf_req);
                goto out;
        }
 
@@ -1033,7 +1019,7 @@ zfcp_fsf_status_read_handler(struct zfcp_fsf_req *fsf_req)
                break;
        }
        mempool_free(status_buffer, adapter->pool.data_status_read);
-       zfcp_fsf_req_cleanup(fsf_req);
+       zfcp_fsf_req_free(fsf_req);
        /*
         * recycle buffer and start new request repeat until outbound
         * queue is empty or adapter shutdown is requested
@@ -2258,7 +2244,7 @@ zfcp_fsf_exchange_port_data(struct zfcp_adapter *adapter,
        wait_event(fsf_req->completion_wq,
                   fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
        del_timer_sync(timer);
-       zfcp_fsf_req_cleanup(fsf_req);
+       zfcp_fsf_req_free(fsf_req);
  out:
        kfree(timer);
        return retval;
@@ -4607,7 +4593,7 @@ zfcp_fsf_req_wait_and_cleanup(struct zfcp_fsf_req *fsf_req,
        *status = fsf_req->status;
 
        /* cleanup request */
-       zfcp_fsf_req_cleanup(fsf_req);
+       zfcp_fsf_req_free(fsf_req);
  out:
        return retval;
 }
@@ -4806,9 +4792,9 @@ zfcp_fsf_req_send(struct zfcp_fsf_req *fsf_req, struct timer_list *timer)
                inc_seq_no = 0;
 
        /* put allocated FSF request at list tail */
-       write_lock_irqsave(&adapter->fsf_req_list_lock, flags);
+       spin_lock_irqsave(&adapter->fsf_req_list_lock, flags);
        list_add_tail(&fsf_req->list, &adapter->fsf_req_list_head);
-       write_unlock_irqrestore(&adapter->fsf_req_list_lock, flags);
+       spin_unlock_irqrestore(&adapter->fsf_req_list_lock, flags);
 
        /* figure out expiration time of timeout and start timeout */
        if (unlikely(timer)) {
@@ -4852,9 +4838,9 @@ zfcp_fsf_req_send(struct zfcp_fsf_req *fsf_req, struct timer_list *timer)
                 */
                if (timer)
                        del_timer(timer);
-               write_lock_irqsave(&adapter->fsf_req_list_lock, flags);
+               spin_lock_irqsave(&adapter->fsf_req_list_lock, flags);
                list_del(&fsf_req->list);
-               write_unlock_irqrestore(&adapter->fsf_req_list_lock, flags);
+               spin_unlock_irqrestore(&adapter->fsf_req_list_lock, flags);
                /*
                 * adjust the number of free SBALs in request queue as well as
                 * position of first one
@@ -4892,25 +4878,4 @@ zfcp_fsf_req_send(struct zfcp_fsf_req *fsf_req, struct timer_list *timer)
        return retval;
 }
 
-/*
- * function:    zfcp_fsf_req_cleanup
- *
- * purpose:    cleans up an FSF request and removes it from the specified list
- *
- * returns:
- *
- * assumption: no pending SB in SBALEs other than QTCB
- */
-void
-zfcp_fsf_req_cleanup(struct zfcp_fsf_req *fsf_req)
-{
-       struct zfcp_adapter *adapter = fsf_req->adapter;
-       unsigned long flags;
-
-       write_lock_irqsave(&adapter->fsf_req_list_lock, flags);
-       list_del(&fsf_req->list);
-       write_unlock_irqrestore(&adapter->fsf_req_list_lock, flags);
-       zfcp_fsf_req_free(fsf_req);
-}
-
 #undef ZFCP_LOG_AREA