From 3d0e91f7ace12499c4b00088e9a6b1361e1bb0ca Mon Sep 17 00:00:00 2001 From: Brian King Date: Wed, 13 Jun 2007 17:12:26 -0500 Subject: [PATCH] [SCSI] ibmvscsi: Add eh_host_reset_handler Adds an eh_host_reset_handler to ibmvscsi which resets the connection to the vscsi server. This patch also adds a timer to internally issues commands to prevent client hangs in the case of a misbehaving server. Tested by modifying the VIOS such that it would occasionally drop one or more request in sequence. Signed-off-by: Brian King Signed-off-by: James Bottomley --- drivers/scsi/ibmvscsi/ibmvscsi.c | 136 ++++++++++++++++++++++++------- drivers/scsi/ibmvscsi/ibmvscsi.h | 1 + 2 files changed, 107 insertions(+), 30 deletions(-) diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c index c63a26e2fb..0a16972b25 100644 --- a/drivers/scsi/ibmvscsi/ibmvscsi.c +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c @@ -509,6 +509,70 @@ static int map_data_for_srp_cmd(struct scsi_cmnd *cmd, return map_single_data(cmd, srp_cmd, dev); } +/** + * purge_requests: Our virtual adapter just shut down. purge any sent requests + * @hostdata: the adapter + */ +static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code) +{ + struct srp_event_struct *tmp_evt, *pos; + unsigned long flags; + + spin_lock_irqsave(hostdata->host->host_lock, flags); + list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) { + list_del(&tmp_evt->list); + del_timer(&tmp_evt->timer); + if (tmp_evt->cmnd) { + tmp_evt->cmnd->result = (error_code << 16); + unmap_cmd_data(&tmp_evt->iu.srp.cmd, + tmp_evt, + tmp_evt->hostdata->dev); + if (tmp_evt->cmnd_done) + tmp_evt->cmnd_done(tmp_evt->cmnd); + } else if (tmp_evt->done) + tmp_evt->done(tmp_evt); + free_event_struct(&tmp_evt->hostdata->pool, tmp_evt); + } + spin_unlock_irqrestore(hostdata->host->host_lock, flags); +} + +/** + * ibmvscsi_reset_host - Reset the connection to the server + * @hostdata: struct ibmvscsi_host_data to reset +*/ +static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata) +{ + scsi_block_requests(hostdata->host); + atomic_set(&hostdata->request_limit, 0); + + purge_requests(hostdata, DID_ERROR); + if ((ibmvscsi_reset_crq_queue(&hostdata->queue, hostdata)) || + (ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0)) || + (vio_enable_interrupts(to_vio_dev(hostdata->dev)))) { + atomic_set(&hostdata->request_limit, -1); + dev_err(hostdata->dev, "error after reset\n"); + } + + scsi_unblock_requests(hostdata->host); +} + +/** + * ibmvscsi_timeout - Internal command timeout handler + * @evt_struct: struct srp_event_struct that timed out + * + * Called when an internally generated command times out +*/ +static void ibmvscsi_timeout(struct srp_event_struct *evt_struct) +{ + struct ibmvscsi_host_data *hostdata = evt_struct->hostdata; + + dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n", + evt_struct->iu.srp.cmd.opcode); + + ibmvscsi_reset_host(hostdata); +} + + /* ------------------------------------------------------------ * Routines for sending and receiving SRPs */ @@ -516,12 +580,14 @@ static int map_data_for_srp_cmd(struct scsi_cmnd *cmd, * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq() * @evt_struct: evt_struct to be sent * @hostdata: ibmvscsi_host_data of host + * @timeout: timeout in seconds - 0 means do not time command * * Returns the value returned from ibmvscsi_send_crq(). (Zero for success) * Note that this routine assumes that host_lock is held for synchronization */ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct, - struct ibmvscsi_host_data *hostdata) + struct ibmvscsi_host_data *hostdata, + unsigned long timeout) { u64 *crq_as_u64 = (u64 *) &evt_struct->crq; int request_status; @@ -577,9 +643,18 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct, */ list_add_tail(&evt_struct->list, &hostdata->sent); + init_timer(&evt_struct->timer); + if (timeout) { + evt_struct->timer.data = (unsigned long) evt_struct; + evt_struct->timer.expires = jiffies + (timeout * HZ); + evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout; + add_timer(&evt_struct->timer); + } + if ((rc = ibmvscsi_send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) { list_del(&evt_struct->list); + del_timer(&evt_struct->timer); dev_err(hostdata->dev, "send error %d\n", rc); atomic_inc(&hostdata->request_limit); @@ -709,7 +784,7 @@ static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd, offsetof(struct srp_indirect_buf, desc_list); } - return ibmvscsi_send_srp_event(evt_struct, hostdata); + return ibmvscsi_send_srp_event(evt_struct, hostdata, 0); } /* ------------------------------------------------------------ @@ -800,7 +875,7 @@ static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata) return; } - if (ibmvscsi_send_srp_event(evt_struct, hostdata)) { + if (ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2)) { dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n"); dma_unmap_single(hostdata->dev, addr, @@ -889,7 +964,7 @@ static int send_srp_login(struct ibmvscsi_host_data *hostdata) */ atomic_set(&hostdata->request_limit, 1); - rc = ibmvscsi_send_srp_event(evt_struct, hostdata); + rc = ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2); spin_unlock_irqrestore(hostdata->host->host_lock, flags); dev_info(hostdata->dev, "sent SRP login\n"); return rc; @@ -969,7 +1044,7 @@ static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd) evt->sync_srp = &srp_rsp; init_completion(&evt->comp); - rsp_rc = ibmvscsi_send_srp_event(evt, hostdata); + rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, init_timeout * 2); spin_unlock_irqrestore(hostdata->host->host_lock, flags); if (rsp_rc != 0) { sdev_printk(KERN_ERR, cmd->device, @@ -1077,7 +1152,7 @@ static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd) evt->sync_srp = &srp_rsp; init_completion(&evt->comp); - rsp_rc = ibmvscsi_send_srp_event(evt, hostdata); + rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, init_timeout * 2); spin_unlock_irqrestore(hostdata->host->host_lock, flags); if (rsp_rc != 0) { sdev_printk(KERN_ERR, cmd->device, @@ -1133,32 +1208,30 @@ static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd) } /** - * purge_requests: Our virtual adapter just shut down. purge any sent requests - * @hostdata: the adapter - */ -static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code) + * ibmvscsi_eh_host_reset_handler - Reset the connection to the server + * @cmd: struct scsi_cmnd having problems +*/ +static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd) { - struct srp_event_struct *tmp_evt, *pos; - unsigned long flags; + unsigned long wait_switch = 0; + struct ibmvscsi_host_data *hostdata = + (struct ibmvscsi_host_data *)cmd->device->host->hostdata; - spin_lock_irqsave(hostdata->host->host_lock, flags); - list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) { - list_del(&tmp_evt->list); - if (tmp_evt->cmnd) { - tmp_evt->cmnd->result = (error_code << 16); - unmap_cmd_data(&tmp_evt->iu.srp.cmd, - tmp_evt, - tmp_evt->hostdata->dev); - if (tmp_evt->cmnd_done) - tmp_evt->cmnd_done(tmp_evt->cmnd); - } else { - if (tmp_evt->done) { - tmp_evt->done(tmp_evt); - } - } - free_event_struct(&tmp_evt->hostdata->pool, tmp_evt); + dev_err(hostdata->dev, "Resetting connection due to error recovery\n"); + + ibmvscsi_reset_host(hostdata); + + for (wait_switch = jiffies + (init_timeout * HZ); + time_before(jiffies, wait_switch) && + atomic_read(&hostdata->request_limit) < 2;) { + + msleep(10); } - spin_unlock_irqrestore(hostdata->host->host_lock, flags); + + if (atomic_read(&hostdata->request_limit) <= 0) + return FAILED; + + return SUCCESS; } /** @@ -1258,6 +1331,8 @@ void ibmvscsi_handle_crq(struct viosrp_crq *crq, atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta, &hostdata->request_limit); + del_timer(&evt_struct->timer); + if (evt_struct->done) evt_struct->done(evt_struct); else @@ -1313,7 +1388,7 @@ static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata, } init_completion(&evt_struct->comp); - rc = ibmvscsi_send_srp_event(evt_struct, hostdata); + rc = ibmvscsi_send_srp_event(evt_struct, hostdata, init_timeout * 2); if (rc == 0) wait_for_completion(&evt_struct->comp); dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL); @@ -1504,6 +1579,7 @@ static struct scsi_host_template driver_template = { .queuecommand = ibmvscsi_queuecommand, .eh_abort_handler = ibmvscsi_eh_abort_handler, .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler, + .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler, .slave_configure = ibmvscsi_slave_configure, .change_queue_depth = ibmvscsi_change_queue_depth, .cmd_per_lun = 16, diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.h b/drivers/scsi/ibmvscsi/ibmvscsi.h index 727ca7c959..b19c2e26c2 100644 --- a/drivers/scsi/ibmvscsi/ibmvscsi.h +++ b/drivers/scsi/ibmvscsi/ibmvscsi.h @@ -70,6 +70,7 @@ struct srp_event_struct { union viosrp_iu iu; void (*cmnd_done) (struct scsi_cmnd *); struct completion comp; + struct timer_list timer; union viosrp_iu *sync_srp; struct srp_direct_buf *ext_list; dma_addr_t ext_list_token; -- 2.39.5