diff options
| -rw-r--r-- | drivers/scsi/ibmvscsi/ibmvscsi.c | 58 | ||||
| -rw-r--r-- | drivers/scsi/ibmvscsi/ibmvscsi.h | 2 |
2 files changed, 40 insertions, 20 deletions
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c index fbc1d5c3b0a..383f5948ba0 100644 --- a/drivers/scsi/ibmvscsi/ibmvscsi.c +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c @@ -85,7 +85,7 @@ static int max_id = 64; static int max_channel = 3; static int init_timeout = 5; -static int max_requests = 50; +static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT; #define IBMVSCSI_VERSION "1.5.8" @@ -538,7 +538,8 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct, int request_status; int rc; - /* If we have exhausted our request limit, just fail this request. + /* If we have exhausted our request limit, just fail this request, + * unless it is for a reset or abort. * Note that there are rare cases involving driver generated requests * (such as task management requests) that the mid layer may think we * can handle more requests (can_queue) when we actually can't @@ -551,9 +552,30 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct, */ if (request_status < -1) goto send_error; - /* Otherwise, if we have run out of requests */ - else if (request_status < 0) - goto send_busy; + /* Otherwise, we may have run out of requests. */ + /* Abort and reset calls should make it through. + * Nothing except abort and reset should use the last two + * slots unless we had two or less to begin with. + */ + else if (request_status < 2 && + evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) { + /* In the case that we have less than two requests + * available, check the server limit as a combination + * of the request limit and the number of requests + * in-flight (the size of the send list). If the + * server limit is greater than 2, return busy so + * that the last two are reserved for reset and abort. + */ + int server_limit = request_status; + struct srp_event_struct *tmp_evt; + + list_for_each_entry(tmp_evt, &hostdata->sent, list) { + server_limit++; + } + + if (server_limit > 2) + goto send_busy; + } } /* Copy the IU into the transfer area */ @@ -572,6 +594,7 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct, printk(KERN_ERR "ibmvscsi: send error %d\n", rc); + atomic_inc(&hostdata->request_limit); goto send_error; } @@ -581,7 +604,8 @@ static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct, unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev); free_event_struct(&hostdata->pool, evt_struct); - return SCSI_MLQUEUE_HOST_BUSY; + atomic_inc(&hostdata->request_limit); + return SCSI_MLQUEUE_HOST_BUSY; send_error: unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev); @@ -831,23 +855,16 @@ static void login_rsp(struct srp_event_struct *evt_struct) printk(KERN_INFO "ibmvscsi: SRP_LOGIN succeeded\n"); - if (evt_struct->xfer_iu->srp.login_rsp.req_lim_delta > - (max_requests - 2)) - evt_struct->xfer_iu->srp.login_rsp.req_lim_delta = - max_requests - 2; + if (evt_struct->xfer_iu->srp.login_rsp.req_lim_delta < 0) + printk(KERN_ERR "ibmvscsi: Invalid request_limit.\n"); - /* Now we know what the real request-limit is */ + /* Now we know what the real request-limit is. + * This value is set rather than added to request_limit because + * request_limit could have been set to -1 by this client. + */ atomic_set(&hostdata->request_limit, evt_struct->xfer_iu->srp.login_rsp.req_lim_delta); - hostdata->host->can_queue = - evt_struct->xfer_iu->srp.login_rsp.req_lim_delta - 2; - - if (hostdata->host->can_queue < 1) { - printk(KERN_ERR "ibmvscsi: Invalid request_limit_delta\n"); - return; - } - /* If we had any pending I/Os, kick them */ scsi_unblock_requests(hostdata->host); @@ -1483,7 +1500,7 @@ static struct scsi_host_template driver_template = { .eh_abort_handler = ibmvscsi_eh_abort_handler, .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler, .cmd_per_lun = 16, - .can_queue = 1, /* Updated after SRP_LOGIN */ + .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT, .this_id = -1, .sg_tablesize = SG_ALL, .use_clustering = ENABLE_CLUSTERING, @@ -1503,6 +1520,7 @@ static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id) vdev->dev.driver_data = NULL; + driver_template.can_queue = max_requests; host = scsi_host_alloc(&driver_template, sizeof(*hostdata)); if (!host) { printk(KERN_ERR "ibmvscsi: couldn't allocate host data\n"); diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.h b/drivers/scsi/ibmvscsi/ibmvscsi.h index 5c6d9358292..77cc1d40f5b 100644 --- a/drivers/scsi/ibmvscsi/ibmvscsi.h +++ b/drivers/scsi/ibmvscsi/ibmvscsi.h @@ -44,6 +44,8 @@ struct Scsi_Host; */ #define MAX_INDIRECT_BUFS 10 +#define IBMVSCSI_MAX_REQUESTS_DEFAULT 100 + /* ------------------------------------------------------------ * Data Structures */ |