block: unify request timeout handling

Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

26 files changed, 142 insertions, 306 deletions

diff --git a/drivers/scsi/aacraid/aachba.c b/drivers/scsi/aacraid/aachba.c
index aa4e77c25273..8abfd06b5a72 100644
--- a/drivers/scsi/aacraid/aachba.c
+++ b/drivers/scsi/aacraid/aachba.c
@@ -1139,7 +1139,7 @@ static struct aac_srb * aac_scsi_common(struct fib * fib, struct scsi_cmnd * cmd
         srbcmd->id       = cpu_to_le32(scmd_id(cmd));
         srbcmd->lun      = cpu_to_le32(cmd->device->lun);
         srbcmd->flags    = cpu_to_le32(flag);
-        timeout = cmd->timeout_per_command/HZ;
+        timeout = cmd->request->timeout/HZ;
         if (timeout == 0)
                 timeout = 1;
         srbcmd->timeout  = cpu_to_le32(timeout);  // timeout in seconds
diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c
index 822d5214692b..c387c15a2128 100644
--- a/drivers/scsi/gdth.c
+++ b/drivers/scsi/gdth.c
@@ -464,7 +464,6 @@ int __gdth_execute(struct scsi_device *sdev, gdth_cmd_str *gdtcmd, char *cmnd,
 
     /* use request field to save the ptr. to completion struct. */
     scp->request = (struct request *)&wait;
-    scp->timeout_per_command = timeout*HZ;
     scp->cmd_len = 12;
     scp->cmnd = cmnd;
     cmndinfo.priority = IOCTL_PRI;
@@ -1995,23 +1994,12 @@ static void gdth_putq(gdth_ha_str *ha, Scsi_Cmnd *scp, unchar priority)
     register Scsi_Cmnd *pscp;
     register Scsi_Cmnd *nscp;
     ulong flags;
-    unchar b, t;
 
     TRACE(("gdth_putq() priority %d\n",priority));
     spin_lock_irqsave(&ha->smp_lock, flags);
 
-    if (!cmndinfo->internal_command) {
+    if (!cmndinfo->internal_command)
         cmndinfo->priority = priority;
-        b = scp->device->channel;
-        t = scp->device->id;
-        if (priority >= DEFAULT_PRI) {
-            if ((b != ha->virt_bus && ha->raw[BUS_L2P(ha,b)].lock) ||
-                (b==ha->virt_bus && t<MAX_HDRIVES && ha->hdr[t].lock)) {
-                TRACE2(("gdth_putq(): locked IO ->update_timeout()\n"));
-                cmndinfo->timeout = gdth_update_timeout(scp, 0);
-            }
-        }
-    }
 
     if (ha->req_first==NULL) {
         ha->req_first = scp;                    /* queue was empty */
@@ -3899,6 +3887,39 @@ static const char *gdth_info(struct Scsi_Host *shp)
     return ((const char *)ha->binfo.type_string);
 }
 
+static enum blk_eh_timer_return gdth_timed_out(struct scsi_cmnd *scp)
+{
+        gdth_ha_str *ha = shost_priv(scp->device->host);
+        struct gdth_cmndinfo *cmndinfo = gdth_cmnd_priv(scp);
+        unchar b, t;
+        ulong flags;
+        enum blk_eh_timer_return retval = BLK_EH_NOT_HANDLED;
+
+        TRACE(("%s() cmd 0x%x\n", scp->cmnd[0], __func__));
+        b = scp->device->channel;
+        t = scp->device->id;
+
+        /*
+         * We don't really honor the command timeout, but we try to
+         * honor 6 times of the actual command timeout! So reset the
+         * timer if this is less than 6th timeout on this command!
+         */
+        if (++cmndinfo->timeout_count < 6)
+                retval = BLK_EH_RESET_TIMER;
+
+        /* Reset the timeout if it is locked IO */
+        spin_lock_irqsave(&ha->smp_lock, flags);
+        if ((b != ha->virt_bus && ha->raw[BUS_L2P(ha, b)].lock) ||
+            (b == ha->virt_bus && t < MAX_HDRIVES && ha->hdr[t].lock)) {
+                TRACE2(("%s(): locked IO, reset timeout\n", __func__));
+                retval = BLK_EH_RESET_TIMER;
+        }
+        spin_unlock_irqrestore(&ha->smp_lock, flags);
+
+        return retval;
+}
+
+
 static int gdth_eh_bus_reset(Scsi_Cmnd *scp)
 {
     gdth_ha_str *ha = shost_priv(scp->device->host);
@@ -3992,7 +4013,7 @@ static int gdth_queuecommand(struct scsi_cmnd *scp,
     BUG_ON(!cmndinfo);
 
     scp->scsi_done = done;
-    gdth_update_timeout(scp, scp->timeout_per_command * 6);
+    cmndinfo->timeout_count = 0;
     cmndinfo->priority = DEFAULT_PRI;
 
     return __gdth_queuecommand(ha, scp, cmndinfo);
@@ -4096,12 +4117,10 @@ static int ioc_lockdrv(void __user *arg)
             ha->hdr[j].lock = 1;
             spin_unlock_irqrestore(&ha->smp_lock, flags);
             gdth_wait_completion(ha, ha->bus_cnt, j);
-            gdth_stop_timeout(ha, ha->bus_cnt, j);
         } else {
             spin_lock_irqsave(&ha->smp_lock, flags);
             ha->hdr[j].lock = 0;
             spin_unlock_irqrestore(&ha->smp_lock, flags);
-            gdth_start_timeout(ha, ha->bus_cnt, j);
             gdth_next(ha);
         }
     } 
@@ -4539,18 +4558,14 @@ static int gdth_ioctl(struct inode *inode, struct file *filep,
                 spin_lock_irqsave(&ha->smp_lock, flags);
                 ha->raw[i].lock = 1;
                 spin_unlock_irqrestore(&ha->smp_lock, flags);
-                for (j = 0; j < ha->tid_cnt; ++j) {
+                for (j = 0; j < ha->tid_cnt; ++j)
                     gdth_wait_completion(ha, i, j);
-                    gdth_stop_timeout(ha, i, j);
-                }
             } else {
                 spin_lock_irqsave(&ha->smp_lock, flags);
                 ha->raw[i].lock = 0;
                 spin_unlock_irqrestore(&ha->smp_lock, flags);
-                for (j = 0; j < ha->tid_cnt; ++j) {
-                    gdth_start_timeout(ha, i, j);
+                for (j = 0; j < ha->tid_cnt; ++j)
                     gdth_next(ha);
-                }
             }
         } 
         break;
@@ -4644,6 +4659,7 @@ static struct scsi_host_template gdth_template = {
         .slave_configure        = gdth_slave_configure,
         .bios_param             = gdth_bios_param,
         .proc_info              = gdth_proc_info,
+        .eh_timed_out           = gdth_timed_out,
         .proc_name              = "gdth",
         .can_queue              = GDTH_MAXCMDS,
         .this_id                = -1,
diff --git a/drivers/scsi/gdth.h b/drivers/scsi/gdth.h
index ca92476727cf..1646444e9bd5 100644
--- a/drivers/scsi/gdth.h
+++ b/drivers/scsi/gdth.h
@@ -916,7 +916,7 @@ typedef struct {
         gdth_cmd_str *internal_cmd_str;         /* crier for internal messages*/
         dma_addr_t sense_paddr;                 /* sense dma-addr */
         unchar priority;
-        int timeout;
+        int timeout_count;                      /* # of timeout calls */
         volatile int wait_for_completion;
         ushort status;
         ulong32 info;
diff --git a/drivers/scsi/gdth_proc.c b/drivers/scsi/gdth_proc.c
index ce0228e26aec..59349a316e13 100644
--- a/drivers/scsi/gdth_proc.c
+++ b/drivers/scsi/gdth_proc.c
@@ -748,69 +748,3 @@ static void gdth_wait_completion(gdth_ha_str *ha, int busnum, int id)
     }
     spin_unlock_irqrestore(&ha->smp_lock, flags);
 }
-
-static void gdth_stop_timeout(gdth_ha_str *ha, int busnum, int id)
-{
-    ulong flags;
-    Scsi_Cmnd *scp;
-    unchar b, t;
-
-    spin_lock_irqsave(&ha->smp_lock, flags);
-
-    for (scp = ha->req_first; scp; scp = (Scsi_Cmnd *)scp->SCp.ptr) {
-        struct gdth_cmndinfo *cmndinfo = gdth_cmnd_priv(scp);
-        if (!cmndinfo->internal_command) {
-            b = scp->device->channel;
-            t = scp->device->id;
-            if (t == (unchar)id && b == (unchar)busnum) {
-                TRACE2(("gdth_stop_timeout(): update_timeout()\n"));
-                cmndinfo->timeout = gdth_update_timeout(scp, 0);
-            }
-        }
-    }
-    spin_unlock_irqrestore(&ha->smp_lock, flags);
-}
-
-static void gdth_start_timeout(gdth_ha_str *ha, int busnum, int id)
-{
-    ulong flags;
-    Scsi_Cmnd *scp;
-    unchar b, t;
-
-    spin_lock_irqsave(&ha->smp_lock, flags);
-
-    for (scp = ha->req_first; scp; scp = (Scsi_Cmnd *)scp->SCp.ptr) {
-        struct gdth_cmndinfo *cmndinfo = gdth_cmnd_priv(scp);
-        if (!cmndinfo->internal_command) {
-            b = scp->device->channel;
-            t = scp->device->id;
-            if (t == (unchar)id && b == (unchar)busnum) {
-                TRACE2(("gdth_start_timeout(): update_timeout()\n"));
-                gdth_update_timeout(scp, cmndinfo->timeout);
-            }
-        }
-    }
-    spin_unlock_irqrestore(&ha->smp_lock, flags);
-}
-
-static int gdth_update_timeout(Scsi_Cmnd *scp, int timeout)
-{
-    int oldto;
-
-    oldto = scp->timeout_per_command;
-    scp->timeout_per_command = timeout;
-
-    if (timeout == 0) {
-        del_timer(&scp->eh_timeout);
-        scp->eh_timeout.data = (unsigned long) NULL;
-        scp->eh_timeout.expires = 0;
-    } else {
-        if (scp->eh_timeout.data != (unsigned long) NULL) 
-            del_timer(&scp->eh_timeout);
-        scp->eh_timeout.data = (unsigned long) scp;
-        scp->eh_timeout.expires = jiffies + timeout;
-        add_timer(&scp->eh_timeout);
-    }
-
-    return oldto;
-}
diff --git a/drivers/scsi/gdth_proc.h b/drivers/scsi/gdth_proc.h
index 45e6fdacf36e..9b900cc9ebe8 100644
--- a/drivers/scsi/gdth_proc.h
+++ b/drivers/scsi/gdth_proc.h
@@ -20,9 +20,6 @@ static char *gdth_ioctl_alloc(gdth_ha_str *ha, int size, int scratch,
                               ulong64 *paddr);
 static void gdth_ioctl_free(gdth_ha_str *ha, int size, char *buf, ulong64 paddr);
 static void gdth_wait_completion(gdth_ha_str *ha, int busnum, int id);
-static void gdth_stop_timeout(gdth_ha_str *ha, int busnum, int id);
-static void gdth_start_timeout(gdth_ha_str *ha, int busnum, int id);
-static int gdth_update_timeout(Scsi_Cmnd *scp, int timeout);
 
 #endif
 
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index 7b1502c0ab6e..87e09f35d3d4 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -756,7 +756,7 @@ static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
         init_event_struct(evt_struct,
                           handle_cmd_rsp,
                           VIOSRP_SRP_FORMAT,
-                          cmnd->timeout_per_command/HZ);
+                          cmnd->request->timeout/HZ);
 
         evt_struct->cmnd = cmnd;
         evt_struct->cmnd_done = done;
diff --git a/drivers/scsi/ide-scsi.c b/drivers/scsi/ide-scsi.c
index 461331d3dc45..81c16cba5417 100644
--- a/drivers/scsi/ide-scsi.c
+++ b/drivers/scsi/ide-scsi.c
@@ -612,7 +612,7 @@ static int idescsi_queue (struct scsi_cmnd *cmd,
         pc->req_xfer = pc->buf_size = scsi_bufflen(cmd);
         pc->scsi_cmd = cmd;
         pc->done = done;
-        pc->timeout = jiffies + cmd->timeout_per_command;
+        pc->timeout = jiffies + cmd->request->timeout;
 
         if (test_bit(IDESCSI_LOG_CMD, &scsi->log)) {
                 printk ("ide-scsi: %s: que %lu, cmd = ", drive->name, cmd->serial_number);
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index e7a3a6554425..d30eb7ba018e 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -3670,7 +3670,8 @@ static int ipr_slave_configure(struct scsi_device *sdev)
                         sdev->no_uld_attach = 1;
                 }
                 if (ipr_is_vset_device(res)) {
-                        sdev->timeout = IPR_VSET_RW_TIMEOUT;
+                        blk_queue_rq_timeout(sdev->request_queue,
+                                             IPR_VSET_RW_TIMEOUT);
                         blk_queue_max_sectors(sdev->request_queue, IPR_VSET_MAX_SECTORS);
                 }
                 if (ipr_is_vset_device(res) || ipr_is_scsi_disk(res))
diff --git a/drivers/scsi/ips.c b/drivers/scsi/ips.c
index bc9e6ddf41df..ef683f0d2b5a 100644
--- a/drivers/scsi/ips.c
+++ b/drivers/scsi/ips.c
@@ -3818,7 +3818,7 @@ ips_send_cmd(ips_ha_t * ha, ips_scb_t * scb)
                 scb->cmd.dcdb.segment_4G = 0;
                 scb->cmd.dcdb.enhanced_sg = 0;
 
-                TimeOut = scb->scsi_cmd->timeout_per_command;
+                TimeOut = scb->scsi_cmd->request->timeout;
 
                 if (ha->subsys->param[4] & 0x00100000) {        /* If NEW Tape DCDB is Supported */
                         if (!scb->sg_len) {
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 299e075a7b34..1eca82420aab 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -1476,12 +1476,12 @@ static void iscsi_start_tx(struct iscsi_conn *conn)
                 scsi_queue_work(conn->session->host, &conn->xmitwork);
 }
 
-static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
+static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
 {
         struct iscsi_cls_session *cls_session;
         struct iscsi_session *session;
         struct iscsi_conn *conn;
-        enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
+        enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
 
         cls_session = starget_to_session(scsi_target(scmd->device));
         session = cls_session->dd_data;
@@ -1494,14 +1494,14 @@ static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
                  * We are probably in the middle of iscsi recovery so let
                  * that complete and handle the error.
                  */
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
                 goto done;
         }
 
         conn = session->leadconn;
         if (!conn) {
                 /* In the middle of shuting down */
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
                 goto done;
         }
 
@@ -1513,20 +1513,21 @@ static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
          */
         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
                             (conn->ping_timeout * HZ), jiffies))
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
         /*
          * if we are about to check the transport then give the command
          * more time
          */
         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
                            jiffies))
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
         /* if in the middle of checking the transport then give us more time */
         if (conn->ping_task)
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
 done:
         spin_unlock(&session->lock);
-        debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
+        debug_scsi("return %s\n", rc == BLK_EH_RESET_TIMER ?
+                                        "timer reset" : "nh");
         return rc;
 }
 
diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
index 48ee8c7f5bdd..837b095ba90d 100644
--- a/drivers/scsi/libsas/sas_ata.c
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -398,7 +398,7 @@ void sas_ata_task_abort(struct sas_task *task)
 
         /* Bounce SCSI-initiated commands to the SCSI EH */
         if (qc->scsicmd) {
-                scsi_req_abort_cmd(qc->scsicmd);
+                blk_abort_request(qc->scsicmd->request);
                 scsi_schedule_eh(qc->scsicmd->device->host);
                 return;
         }
diff --git a/drivers/scsi/libsas/sas_internal.h b/drivers/scsi/libsas/sas_internal.h
index b4f9368f116a..0001374bd6b2 100644
--- a/drivers/scsi/libsas/sas_internal.h
+++ b/drivers/scsi/libsas/sas_internal.h
@@ -55,7 +55,7 @@ void sas_unregister_phys(struct sas_ha_struct *sas_ha);
 int  sas_register_ports(struct sas_ha_struct *sas_ha);
 void sas_unregister_ports(struct sas_ha_struct *sas_ha);
 
-enum scsi_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *);
+enum blk_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *);
 
 int  sas_init_queue(struct sas_ha_struct *sas_ha);
 int  sas_init_events(struct sas_ha_struct *sas_ha);
diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c
index a8e3ef309070..744838780ada 100644
--- a/drivers/scsi/libsas/sas_scsi_host.c
+++ b/drivers/scsi/libsas/sas_scsi_host.c
@@ -673,43 +673,43 @@ out:
         return;
 }
 
-enum scsi_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
+enum blk_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
 {
         struct sas_task *task = TO_SAS_TASK(cmd);
         unsigned long flags;
 
         if (!task) {
-                cmd->timeout_per_command /= 2;
+                cmd->request->timeout /= 2;
                 SAS_DPRINTK("command 0x%p, task 0x%p, gone: %s\n",
-                            cmd, task, (cmd->timeout_per_command ?
-                            "EH_RESET_TIMER" : "EH_NOT_HANDLED"));
-                if (!cmd->timeout_per_command)
-                        return EH_NOT_HANDLED;
-                return EH_RESET_TIMER;
+                            cmd, task, (cmd->request->timeout ?
+                            "BLK_EH_RESET_TIMER" : "BLK_EH_NOT_HANDLED"));
+                if (!cmd->request->timeout)
+                        return BLK_EH_NOT_HANDLED;
+                return BLK_EH_RESET_TIMER;
         }
 
         spin_lock_irqsave(&task->task_state_lock, flags);
         BUG_ON(task->task_state_flags & SAS_TASK_STATE_ABORTED);
         if (task->task_state_flags & SAS_TASK_STATE_DONE) {
                 spin_unlock_irqrestore(&task->task_state_lock, flags);
-                SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_HANDLED\n",
-                            cmd, task);
-                return EH_HANDLED;
+                SAS_DPRINTK("command 0x%p, task 0x%p, timed out: "
+                            "BLK_EH_HANDLED\n", cmd, task);
+                return BLK_EH_HANDLED;
         }
         if (!(task->task_state_flags & SAS_TASK_AT_INITIATOR)) {
                 spin_unlock_irqrestore(&task->task_state_lock, flags);
                 SAS_DPRINTK("command 0x%p, task 0x%p, not at initiator: "
-                            "EH_RESET_TIMER\n",
+                            "BLK_EH_RESET_TIMER\n",
                             cmd, task);
-                return EH_RESET_TIMER;
+                return BLK_EH_RESET_TIMER;
         }
         task->task_state_flags |= SAS_TASK_STATE_ABORTED;
         spin_unlock_irqrestore(&task->task_state_lock, flags);
 
-        SAS_DPRINTK("command 0x%p, task 0x%p, timed out: EH_NOT_HANDLED\n",
+        SAS_DPRINTK("command 0x%p, task 0x%p, timed out: BLK_EH_NOT_HANDLED\n",
                     cmd, task);
 
-        return EH_NOT_HANDLED;
+        return BLK_EH_NOT_HANDLED;
 }
 
 int sas_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
@@ -1039,7 +1039,7 @@ void sas_task_abort(struct sas_task *task)
                 return;
         }
 
-        scsi_req_abort_cmd(sc);
+        blk_abort_request(sc->request);
         scsi_schedule_eh(sc->device->host);
 }
 
diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
index 97b763378e7d..afe1de998763 100644
--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -1167,7 +1167,7 @@ static int megasas_generic_reset(struct scsi_cmnd *scmd)
  * cmd has not been completed within the timeout period.
  */
 static enum
-scsi_eh_timer_return megasas_reset_timer(struct scsi_cmnd *scmd)
+blk_eh_timer_return megasas_reset_timer(struct scsi_cmnd *scmd)
 {
         struct megasas_cmd *cmd = (struct megasas_cmd *)scmd->SCp.ptr;
         struct megasas_instance *instance;
@@ -1175,7 +1175,7 @@ scsi_eh_timer_return megasas_reset_timer(struct scsi_cmnd *scmd)
 
         if (time_after(jiffies, scmd->jiffies_at_alloc +
                                 (MEGASAS_DEFAULT_CMD_TIMEOUT * 2) * HZ)) {
-                return EH_NOT_HANDLED;
+                return BLK_EH_NOT_HANDLED;
         }
 
         instance = cmd->instance;
@@ -1189,7 +1189,7 @@ scsi_eh_timer_return megasas_reset_timer(struct scsi_cmnd *scmd)
 
                 spin_unlock_irqrestore(instance->host->host_lock, flags);
         }
-        return EH_RESET_TIMER;
+        return BLK_EH_RESET_TIMER;
 }
 
 /**
diff --git a/drivers/scsi/ncr53c8xx.c b/drivers/scsi/ncr53c8xx.c
index c57c94c0ffd2..3b7240e40819 100644
--- a/drivers/scsi/ncr53c8xx.c
+++ b/drivers/scsi/ncr53c8xx.c
@@ -4170,8 +4170,8 @@ static int ncr_queue_command (struct ncb *np, struct scsi_cmnd *cmd)
         **
         **----------------------------------------------------
         */
-        if (np->settle_time && cmd->timeout_per_command >= HZ) {
-                u_long tlimit = jiffies + cmd->timeout_per_command - HZ;
+        if (np->settle_time && cmd->request->timeout >= HZ) {
+                u_long tlimit = jiffies + cmd->request->timeout - HZ;
                 if (time_after(np->settle_time, tlimit))
                         np->settle_time = tlimit;
         }
diff --git a/drivers/scsi/qla1280.c b/drivers/scsi/qla1280.c
index 37f9ba0cd798..b6cd12b2e996 100644
--- a/drivers/scsi/qla1280.c
+++ b/drivers/scsi/qla1280.c
@@ -2845,7 +2845,7 @@ qla1280_64bit_start_scsi(struct scsi_qla_host *ha, struct srb * sp)
         memset(((char *)pkt + 8), 0, (REQUEST_ENTRY_SIZE - 8));
 
         /* Set ISP command timeout. */
-        pkt->timeout = cpu_to_le16(cmd->timeout_per_command/HZ);
+        pkt->timeout = cpu_to_le16(cmd->request->timeout/HZ);
 
         /* Set device target ID and LUN */
         pkt->lun = SCSI_LUN_32(cmd);
@@ -3114,7 +3114,7 @@ qla1280_32bit_start_scsi(struct scsi_qla_host *ha, struct srb * sp)
         memset(((char *)pkt + 8), 0, (REQUEST_ENTRY_SIZE - 8));
 
         /* Set ISP command timeout. */
-        pkt->timeout = cpu_to_le16(cmd->timeout_per_command/HZ);
+        pkt->timeout = cpu_to_le16(cmd->request->timeout/HZ);
 
         /* Set device target ID and LUN */
         pkt->lun = SCSI_LUN_32(cmd);
diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index 88bebb13bc52..de8279ad7d89 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -1542,7 +1542,7 @@ static int qla4xxx_eh_device_reset(struct scsi_cmnd *cmd)
         DEBUG2(printk(KERN_INFO
                       "scsi%ld: DEVICE_RESET cmd=%p jiffies = 0x%lx, to=%x,"
                       "dpc_flags=%lx, status=%x allowed=%d\n", ha->host_no,
-                      cmd, jiffies, cmd->timeout_per_command / HZ,
+                      cmd, jiffies, cmd->request->timeout / HZ,
                       ha->dpc_flags, cmd->result, cmd->allowed));
 
         /* FIXME: wait for hba to go online */
@@ -1598,7 +1598,7 @@ static int qla4xxx_eh_target_reset(struct scsi_cmnd *cmd)
         DEBUG2(printk(KERN_INFO
                       "scsi%ld: TARGET_DEVICE_RESET cmd=%p jiffies = 0x%lx, "
                       "to=%x,dpc_flags=%lx, status=%x allowed=%d\n",
-                      ha->host_no, cmd, jiffies, cmd->timeout_per_command / HZ,
+                      ha->host_no, cmd, jiffies, cmd->request->timeout / HZ,
                       ha->dpc_flags, cmd->result, cmd->allowed));
 
         stat = qla4xxx_reset_target(ha, ddb_entry);
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index ee6be596503d..dbeb86cafc0d 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -291,7 +291,6 @@ struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask)
                 unsigned long flags;
 
                 cmd->device = dev;
-                init_timer(&cmd->eh_timeout);
                 INIT_LIST_HEAD(&cmd->list);
                 spin_lock_irqsave(&dev->list_lock, flags);
                 list_add_tail(&cmd->list, &dev->cmd_list);
@@ -652,14 +651,19 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
         unsigned long timeout;
         int rtn = 0;
 
+        /*
+         * We will use a queued command if possible, otherwise we will
+         * emulate the queuing and calling of completion function ourselves.
+         */
+        atomic_inc(&cmd->device->iorequest_cnt);
+
         /* check if the device is still usable */
         if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
                 /* in SDEV_DEL we error all commands. DID_NO_CONNECT
                  * returns an immediate error upwards, and signals
                  * that the device is no longer present */
                 cmd->result = DID_NO_CONNECT << 16;
-                atomic_inc(&cmd->device->iorequest_cnt);
-                __scsi_done(cmd);
+                scsi_done(cmd);
                 /* return 0 (because the command has been processed) */
                 goto out;
         }
@@ -672,6 +676,7 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
                  * future requests should not occur until the device 
                  * transitions out of the suspend state.
                  */
+
                 scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
 
                 SCSI_LOG_MLQUEUE(3, printk("queuecommand : device blocked \n"));
@@ -714,21 +719,9 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
                 host->resetting = 0;
         }
 
-        /* 
-         * AK: unlikely race here: for some reason the timer could
-         * expire before the serial number is set up below.
-         */
-        scsi_add_timer(cmd, cmd->timeout_per_command, scsi_times_out);
-
         scsi_log_send(cmd);
 
         /*
-         * We will use a queued command if possible, otherwise we will
-         * emulate the queuing and calling of completion function ourselves.
-         */
-        atomic_inc(&cmd->device->iorequest_cnt);
-
-        /*
          * Before we queue this command, check if the command
          * length exceeds what the host adapter can handle.
          */
@@ -744,6 +737,12 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
         }
 
         spin_lock_irqsave(host->host_lock, flags);
+        /*
+         * AK: unlikely race here: for some reason the timer could
+         * expire before the serial number is set up below.
+         *
+         * TODO: kill serial or move to blk layer
+         */
         scsi_cmd_get_serial(host, cmd); 
 
         if (unlikely(host->shost_state == SHOST_DEL)) {
@@ -754,12 +753,8 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
         }
         spin_unlock_irqrestore(host->host_lock, flags);
         if (rtn) {
-                if (scsi_delete_timer(cmd)) {
-                        atomic_inc(&cmd->device->iodone_cnt);
-                        scsi_queue_insert(cmd,
-                                          (rtn == SCSI_MLQUEUE_DEVICE_BUSY) ?
-                                          rtn : SCSI_MLQUEUE_HOST_BUSY);
-                }
+                scsi_queue_insert(cmd, (rtn == SCSI_MLQUEUE_DEVICE_BUSY) ?
+                                                rtn : SCSI_MLQUEUE_HOST_BUSY);
                 SCSI_LOG_MLQUEUE(3,
                     printk("queuecommand : request rejected\n"));
         }
@@ -770,24 +765,6 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
 }
 
 /**
- * scsi_req_abort_cmd -- Request command recovery for the specified command
- * @cmd: pointer to the SCSI command of interest
- *
- * This function requests that SCSI Core start recovery for the
- * command by deleting the timer and adding the command to the eh
- * queue.  It can be called by either LLDDs or SCSI Core.  LLDDs who
- * implement their own error recovery MAY ignore the timeout event if
- * they generated scsi_req_abort_cmd.
- */
-void scsi_req_abort_cmd(struct scsi_cmnd *cmd)
-{
-        if (!scsi_delete_timer(cmd))
-                return;
-        scsi_times_out(cmd);
-}
-EXPORT_SYMBOL(scsi_req_abort_cmd);
-
-/**
  * scsi_done - Enqueue the finished SCSI command into the done queue.
  * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives
  * ownership back to SCSI Core -- i.e. the LLDD has finished with it.
@@ -802,42 +779,7 @@ EXPORT_SYMBOL(scsi_req_abort_cmd);
  */
 static void scsi_done(struct scsi_cmnd *cmd)
 {
-        /*
-         * We don't have to worry about this one timing out anymore.
-         * If we are unable to remove the timer, then the command
-         * has already timed out.  In which case, we have no choice but to
-         * let the timeout function run, as we have no idea where in fact
-         * that function could really be.  It might be on another processor,
-         * etc, etc.
-         */
-        if (!scsi_delete_timer(cmd))
-                return;
-        __scsi_done(cmd);
-}
-
-/* Private entry to scsi_done() to complete a command when the timer
- * isn't running --- used by scsi_times_out */
-void __scsi_done(struct scsi_cmnd *cmd)
-{
-        struct request *rq = cmd->request;
-
-        /*
-         * Set the serial numbers back to zero
-         */
-        cmd->serial_number = 0;
-
-        atomic_inc(&cmd->device->iodone_cnt);
-        if (cmd->result)
-                atomic_inc(&cmd->device->ioerr_cnt);
-
-        BUG_ON(!rq);
-
-        /*
-         * The uptodate/nbytes values don't matter, as we allow partial
-         * completes and thus will check this in the softirq callback
-         */
-        rq->completion_data = cmd;
-        blk_complete_request(rq);
+        blk_complete_request(cmd->request);
 }
 
 /* Move this to a header if it becomes more generally useful */
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 39ce3aba1dac..fecefa05cb62 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -112,69 +112,8 @@ int scsi_eh_scmd_add(struct scsi_cmnd *scmd, int eh_flag)
 }
 
 /**
- * scsi_add_timer - Start timeout timer for a single scsi command.
- * @scmd:       scsi command that is about to start running.
- * @timeout:    amount of time to allow this command to run.
- * @complete:   timeout function to call if timer isn't canceled.
- *
- * Notes:
- *    This should be turned into an inline function.  Each scsi command
- *    has its own timer, and as it is added to the queue, we set up the
- *    timer.  When the command completes, we cancel the timer.
- */
-void scsi_add_timer(struct scsi_cmnd *scmd, int timeout,
-                    void (*complete)(struct scsi_cmnd *))
-{
-
-        /*
-         * If the clock was already running for this command, then
-         * first delete the timer.  The timer handling code gets rather
-         * confused if we don't do this.
-         */
-        if (scmd->eh_timeout.function)
-                del_timer(&scmd->eh_timeout);
-
-        scmd->eh_timeout.data = (unsigned long)scmd;
-        scmd->eh_timeout.expires = jiffies + timeout;
-        scmd->eh_timeout.function = (void (*)(unsigned long)) complete;
-
-        SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p, time:"
-                                          " %d, (%p)\n", __func__,
-                                          scmd, timeout, complete));
-
-        add_timer(&scmd->eh_timeout);
-}
-
-/**
- * scsi_delete_timer - Delete/cancel timer for a given function.
- * @scmd:       Cmd that we are canceling timer for
- *
- * Notes:
- *     This should be turned into an inline function.
- *
- * Return value:
- *     1 if we were able to detach the timer.  0 if we blew it, and the
- *     timer function has already started to run.
- */
-int scsi_delete_timer(struct scsi_cmnd *scmd)
-{
-        int rtn;
-
-        rtn = del_timer(&scmd->eh_timeout);
-
-        SCSI_LOG_ERROR_RECOVERY(5, printk("%s: scmd: %p,"
-                                         " rtn: %d\n", __func__,
-                                         scmd, rtn));
-
-        scmd->eh_timeout.data = (unsigned long)NULL;
-        scmd->eh_timeout.function = NULL;
-
-        return rtn;
-}
-
-/**
  * scsi_times_out - Timeout function for normal scsi commands.
- * @scmd:       Cmd that is timing out.
+ * @req:        request that is timing out.
  *
  * Notes:
  *     We do not need to lock this.  There is the potential for a race
@@ -182,9 +121,11 @@ int scsi_delete_timer(struct scsi_cmnd *scmd)
  *     normal completion function determines that the timer has already
  *     fired, then it mustn't do anything.
  */
-void scsi_times_out(struct scsi_cmnd *scmd)
+enum blk_eh_timer_return scsi_times_out(struct request *req)
 {
-        enum scsi_eh_timer_return (* eh_timed_out)(struct scsi_cmnd *);
+        struct scsi_cmnd *scmd = req->special;
+        enum blk_eh_timer_return (*eh_timed_out)(struct scsi_cmnd *);
+        enum blk_eh_timer_return rtn = BLK_EH_NOT_HANDLED;
 
         scsi_log_completion(scmd, TIMEOUT_ERROR);
 
@@ -196,22 +137,20 @@ void scsi_times_out(struct scsi_cmnd *scmd)
                 eh_timed_out = NULL;
 
         if (eh_timed_out)
-                switch (eh_timed_out(scmd)) {
-                case EH_HANDLED:
-                        __scsi_done(scmd);
-                        return;
-                case EH_RESET_TIMER:
-                        scsi_add_timer(scmd, scmd->timeout_per_command,
-                                       scsi_times_out);
-                        return;
-                case EH_NOT_HANDLED:
+                rtn = eh_timed_out(scmd);
+                switch (rtn) {
+                case BLK_EH_NOT_HANDLED:
                         break;
+                default:
+                        return rtn;
                 }
 
         if (unlikely(!scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD))) {
                 scmd->result |= DID_TIME_OUT << 16;
-                __scsi_done(scmd);
+                return BLK_EH_HANDLED;
         }
+
+        return BLK_EH_NOT_HANDLED;
 }
 
 /**
@@ -1793,7 +1732,6 @@ scsi_reset_provider(struct scsi_device *dev, int flag)
 
         blk_rq_init(NULL, &req);
         scmd->request = &req;
-        memset(&scmd->eh_timeout, 0, sizeof(scmd->eh_timeout));
 
         scmd->cmnd = req.cmd;
 
@@ -1804,8 +1742,6 @@ scsi_reset_provider(struct scsi_device *dev, int flag)
 
         scmd->sc_data_direction         = DMA_BIDIRECTIONAL;
 
-        init_timer(&scmd->eh_timeout);
-
         spin_lock_irqsave(shost->host_lock, flags);
         shost->tmf_in_progress = 1;
         spin_unlock_irqrestore(shost->host_lock, flags);
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 62307bd794a9..e7686500e9dd 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1181,7 +1181,6 @@ int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
         
         cmd->transfersize = req->data_len;
         cmd->allowed = req->retries;
-        cmd->timeout_per_command = req->timeout;
         return BLKPREP_OK;
 }
 EXPORT_SYMBOL(scsi_setup_blk_pc_cmnd);
@@ -1416,17 +1415,26 @@ static void scsi_kill_request(struct request *req, struct request_queue *q)
         spin_unlock(shost->host_lock);
         spin_lock(sdev->request_queue->queue_lock);
 
-        __scsi_done(cmd);
+        blk_complete_request(req);
 }
 
 static void scsi_softirq_done(struct request *rq)
 {
-        struct scsi_cmnd *cmd = rq->completion_data;
-        unsigned long wait_for = (cmd->allowed + 1) * cmd->timeout_per_command;
+        struct scsi_cmnd *cmd = rq->special;
+        unsigned long wait_for = (cmd->allowed + 1) * rq->timeout;
         int disposition;
 
         INIT_LIST_HEAD(&cmd->eh_entry);
 
+        /*
+         * Set the serial numbers back to zero
+         */
+        cmd->serial_number = 0;
+
+        atomic_inc(&cmd->device->iodone_cnt);
+        if (cmd->result)
+                atomic_inc(&cmd->device->ioerr_cnt);
+
         disposition = scsi_decide_disposition(cmd);
         if (disposition != SUCCESS &&
             time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
@@ -1675,6 +1683,7 @@ struct request_queue *scsi_alloc_queue(struct scsi_device *sdev)
 
         blk_queue_prep_rq(q, scsi_prep_fn);
         blk_queue_softirq_done(q, scsi_softirq_done);
+        blk_queue_rq_timed_out(q, scsi_times_out);
         return q;
 }
 
diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h
index 79f0f7511204..6cddd5dd323c 100644
--- a/drivers/scsi/scsi_priv.h
+++ b/drivers/scsi/scsi_priv.h
@@ -4,6 +4,7 @@
 #include <linux/device.h>
 
 struct request_queue;
+struct request;
 struct scsi_cmnd;
 struct scsi_device;
 struct scsi_host_template;
@@ -27,7 +28,6 @@ extern void scsi_exit_hosts(void);
 extern int scsi_dispatch_cmd(struct scsi_cmnd *cmd);
 extern int scsi_setup_command_freelist(struct Scsi_Host *shost);
 extern void scsi_destroy_command_freelist(struct Scsi_Host *shost);
-extern void __scsi_done(struct scsi_cmnd *cmd);
 #ifdef CONFIG_SCSI_LOGGING
 void scsi_log_send(struct scsi_cmnd *cmd);
 void scsi_log_completion(struct scsi_cmnd *cmd, int disposition);
@@ -49,10 +49,7 @@ extern int __init scsi_init_devinfo(void);
 extern void scsi_exit_devinfo(void);
 
 /* scsi_error.c */
-extern void scsi_add_timer(struct scsi_cmnd *, int,
-                void (*)(struct scsi_cmnd *));
-extern int scsi_delete_timer(struct scsi_cmnd *);
-extern void scsi_times_out(struct scsi_cmnd *cmd);
+extern enum blk_eh_timer_return scsi_times_out(struct request *req);
 extern int scsi_error_handler(void *host);
 extern int scsi_decide_disposition(struct scsi_cmnd *cmd);
 extern void scsi_eh_wakeup(struct Scsi_Host *shost);
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index ab3c71869be5..7f618ee5ecea 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -560,12 +560,15 @@ sdev_rd_attr (vendor, "%.8s\n");
 sdev_rd_attr (model, "%.16s\n");
 sdev_rd_attr (rev, "%.4s\n");
 
+/*
+ * TODO: can we make these symlinks to the block layer ones?
+ */
 static ssize_t
 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
 {
         struct scsi_device *sdev;
         sdev = to_scsi_device(dev);
-        return snprintf (buf, 20, "%d\n", sdev->timeout / HZ);
+        return snprintf(buf, 20, "%d\n", sdev->request_queue->rq_timeout / HZ);
 }
 
 static ssize_t
@@ -576,7 +579,7 @@ sdev_store_timeout (struct device *dev, struct device_attribute *attr,
         int timeout;
         sdev = to_scsi_device(dev);
         sscanf (buf, "%d\n", &timeout);
-        sdev->timeout = timeout * HZ;
+        blk_queue_rq_timeout(sdev->request_queue, timeout * HZ);
         return count;
 }
 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c
index 56823fd1fb84..9168883d0dfe 100644
--- a/drivers/scsi/scsi_transport_fc.c
+++ b/drivers/scsi/scsi_transport_fc.c
@@ -1950,15 +1950,15 @@ static int fc_vport_match(struct attribute_container *cont,
  * Notes:
  *      This routine assumes no locks are held on entry.
  */
-static enum scsi_eh_timer_return
+static enum blk_eh_timer_return
 fc_timed_out(struct scsi_cmnd *scmd)
 {
         struct fc_rport *rport = starget_to_rport(scsi_target(scmd->device));
 
         if (rport->port_state == FC_PORTSTATE_BLOCKED)
-                return EH_RESET_TIMER;
+                return BLK_EH_RESET_TIMER;
 
-        return EH_NOT_HANDLED;
+        return BLK_EH_NOT_HANDLED;
 }
 
 /*
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index cb115d1bf228..c0cf4acda7de 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -383,7 +383,6 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
         sector_t block = rq->sector;
         sector_t threshold;
         unsigned int this_count = rq->nr_sectors;
-        unsigned int timeout = sdp->timeout;
         int ret;
 
         if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
@@ -584,7 +583,6 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq)
         SCpnt->transfersize = sdp->sector_size;
         SCpnt->underflow = this_count << 9;
         SCpnt->allowed = SD_MAX_RETRIES;
-        SCpnt->timeout_per_command = timeout;
 
         /*
          * This indicates that the command is ready from our end to be
@@ -1878,11 +1876,12 @@ static int sd_probe(struct device *dev)
         sdkp->openers = 0;
         sdkp->previous_state = 1;
 
-        if (!sdp->timeout) {
+        if (!sdp->request_queue->rq_timeout) {
                 if (sdp->type != TYPE_MOD)
-                        sdp->timeout = SD_TIMEOUT;
+                        blk_queue_rq_timeout(sdp->request_queue, SD_TIMEOUT);
                 else
-                        sdp->timeout = SD_MOD_TIMEOUT;
+                        blk_queue_rq_timeout(sdp->request_queue,
+                                             SD_MOD_TIMEOUT);
         }
 
         device_initialize(&sdkp->dev);
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 8dbe3798d5fd..0f17009c99d2 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -331,7 +331,7 @@ static int sr_done(struct scsi_cmnd *SCpnt)
 
 static int sr_prep_fn(struct request_queue *q, struct request *rq)
 {
-        int block=0, this_count, s_size, timeout = SR_TIMEOUT;
+        int block = 0, this_count, s_size;
         struct scsi_cd *cd;
         struct scsi_cmnd *SCpnt;
         struct scsi_device *sdp = q->queuedata;
@@ -461,7 +461,6 @@ static int sr_prep_fn(struct request_queue *q, struct request *rq)
         SCpnt->transfersize = cd->device->sector_size;
         SCpnt->underflow = this_count << 9;
         SCpnt->allowed = MAX_RETRIES;
-        SCpnt->timeout_per_command = timeout;
 
         /*
          * This indicates that the command is ready from our end to be
@@ -620,6 +619,8 @@ static int sr_probe(struct device *dev)
         disk->fops = &sr_bdops;
         disk->flags = GENHD_FL_CD;
 
+        blk_queue_rq_timeout(sdev->request_queue, SR_TIMEOUT);
+
         cd->device = sdev;
         cd->disk = disk;
         cd->driver = &sr_template;
diff --git a/drivers/scsi/sym53c8xx_2/sym_glue.c b/drivers/scsi/sym53c8xx_2/sym_glue.c
index d39107b7669b..f4e6cde1fd0d 100644
--- a/drivers/scsi/sym53c8xx_2/sym_glue.c
+++ b/drivers/scsi/sym53c8xx_2/sym_glue.c
@@ -519,8 +519,8 @@ static int sym53c8xx_queue_command(struct scsi_cmnd *cmd,
          *  Shorten our settle_time if needed for 
          *  this command not to time out.
          */
-        if (np->s.settle_time_valid && cmd->timeout_per_command) {
-                unsigned long tlimit = jiffies + cmd->timeout_per_command;
+        if (np->s.settle_time_valid && cmd->request->timeout) {
+                unsigned long tlimit = jiffies + cmd->request->timeout;
                 tlimit -= SYM_CONF_TIMER_INTERVAL*2;
                 if (time_after(np->s.settle_time, tlimit)) {
                         np->s.settle_time = tlimit;