summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/qla4xxx/ql4_mbx.c
diff options
context:
space:
mode:
authorKaren Higgins2013-01-21 05:51:00 +0100
committerJames Bottomley2013-01-30 03:47:16 +0100
commit5b1c1bff07d579f8a7b672d4e5262d52eba5ef01 (patch)
tree83b802ffe3e95af2c8e2ecfc1fc907143149f274 /drivers/scsi/qla4xxx/ql4_mbx.c
parent[SCSI] qla4xxx: Remove unnecessary code from qla4xxx_init_local_data (diff)
downloadkernel-qcow2-linux-5b1c1bff07d579f8a7b672d4e5262d52eba5ef01.tar.gz
kernel-qcow2-linux-5b1c1bff07d579f8a7b672d4e5262d52eba5ef01.tar.xz
kernel-qcow2-linux-5b1c1bff07d579f8a7b672d4e5262d52eba5ef01.zip
[SCSI] qla4xxx: Throttle active IOCBs to firmware limits
Problem: QLA4xxx firmware may assert if given more IOCBs than it can handle. Solution: The driver was updated to throttle the number of active IOCBs based on the total number of IOCB buffers received from get_firmware_status mbx_sts[2]. Signed-off-by: Karen Higgins <karen.higgins@qlogic.com> Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/qla4xxx/ql4_mbx.c')
-rw-r--r--drivers/scsi/qla4xxx/ql4_mbx.c20
1 files changed, 18 insertions, 2 deletions
diff --git a/drivers/scsi/qla4xxx/ql4_mbx.c b/drivers/scsi/qla4xxx/ql4_mbx.c
index 1c57c227c808..81e738d61ec0 100644
--- a/drivers/scsi/qla4xxx/ql4_mbx.c
+++ b/drivers/scsi/qla4xxx/ql4_mbx.c
@@ -697,8 +697,24 @@ int qla4xxx_get_firmware_status(struct scsi_qla_host * ha)
return QLA_ERROR;
}
- ql4_printk(KERN_INFO, ha, "%ld firmware IOCBs available (%d).\n",
- ha->host_no, mbox_sts[2]);
+ /* High-water mark of IOCBs */
+ ha->iocb_hiwat = mbox_sts[2];
+ DEBUG2(ql4_printk(KERN_INFO, ha,
+ "%s: firmware IOCBs available = %d\n", __func__,
+ ha->iocb_hiwat));
+
+ if (ha->iocb_hiwat > IOCB_HIWAT_CUSHION)
+ ha->iocb_hiwat -= IOCB_HIWAT_CUSHION;
+
+ /* Ideally, we should not enter this code, as the # of firmware
+ * IOCBs is hard-coded in the firmware. We set a default
+ * iocb_hiwat here just in case */
+ if (ha->iocb_hiwat == 0) {
+ ha->iocb_hiwat = REQUEST_QUEUE_DEPTH / 4;
+ DEBUG2(ql4_printk(KERN_WARNING, ha,
+ "%s: Setting IOCB's to = %d\n", __func__,
+ ha->iocb_hiwat));
+ }
return QLA_SUCCESS;
}