linux/drivers/scsi/lpfc/lpfc_nvme.h
James Smart cf1a1d3e2d scsi: lpfc: Fix random heartbeat timeouts during heavy IO
NVME targets appear to randomly disconnect from the initiator when
running heavy IO.

The error is due to the host aggregate (across all controllers) io load
was beyond the maximum exchange count for nvme on the adapter. The
driver was properly returning a resource busy status, but the io load
was so great heartbeat commands would be bounced and not have a
successful retry within the fuzz amount for the nvme heartbeat (yes, a
very high io load!). Thus the target was terminating the controller due
to a keep alive failure.

Resolve by reserving a few exchanges (by counters) which can be used
when the adapter is out of normal exchanges and the command is a NVME
heartbeat command. As counters are used, while the reserved command is
outstanding, as soon as any other exchange completes, the counters are
adjusted and the reserved count is replenished. The heartbeat completes
execution in a normal fashion.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-12-20 21:11:44 -05:00

106 lines
3.6 KiB
C

/*******************************************************************
* This file is part of the Emulex Linux Device Driver for *
* Fibre Channel Host Bus Adapters. *
* Copyright (C) 2017 Broadcom. All Rights Reserved. The term *
* “Broadcom” refers to Broadcom Limited and/or its subsidiaries. *
* Copyright (C) 2004-2016 Emulex. All rights reserved. *
* EMULEX and SLI are trademarks of Emulex. *
* www.broadcom.com *
* Portions Copyright (C) 2004-2005 Christoph Hellwig *
* *
* This program is free software; you can redistribute it and/or *
* modify it under the terms of version 2 of the GNU General *
* Public License as published by the Free Software Foundation. *
* This program is distributed in the hope that it will be useful. *
* ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND *
* WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, *
* FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT, ARE *
* DISCLAIMED, EXCEPT TO THE EXTENT THAT SUCH DISCLAIMERS ARE HELD *
* TO BE LEGALLY INVALID. See the GNU General Public License for *
* more details, a copy of which can be found in the file COPYING *
* included with this package. *
********************************************************************/
#define LPFC_NVME_DEFAULT_SEGS (64 + 1) /* 256K IOs */
#define LPFC_NVME_WQSIZE 1024
#define LPFC_NVME_CQSIZE 4096
#define LPFC_NVME_ERSP_LEN 0x20
#define LPFC_NVME_WAIT_TMO 10
#define LPFC_NVME_EXPEDITE_XRICNT 8
struct lpfc_nvme_qhandle {
uint32_t index; /* WQ index to use */
uint32_t qidx; /* queue index passed to create */
uint32_t cpu_id; /* current cpu id at time of create */
};
/* Declare nvme-based local and remote port definitions. */
struct lpfc_nvme_lport {
struct lpfc_vport *vport;
struct completion lport_unreg_done;
/* Add sttats counters here */
};
struct lpfc_nvme_rport {
struct lpfc_nvme_lport *lport;
struct nvme_fc_remote_port *remoteport;
struct lpfc_nodelist *ndlp;
struct completion rport_unreg_done;
};
struct lpfc_nvme_buf {
struct list_head list;
struct nvmefc_fcp_req *nvmeCmd;
struct lpfc_nvme_rport *nrport;
struct lpfc_nodelist *ndlp;
uint32_t timeout;
uint16_t flags; /* TBD convert exch_busy to flags */
#define LPFC_SBUF_XBUSY 0x1 /* SLI4 hba reported XB on WCQE cmpl */
uint16_t exch_busy; /* SLI4 hba reported XB on complete WCQE */
uint16_t status; /* From IOCB Word 7- ulpStatus */
uint16_t cpu;
uint16_t qidx;
uint16_t sqid;
uint32_t result; /* From IOCB Word 4. */
uint32_t seg_cnt; /* Number of scatter-gather segments returned by
* dma_map_sg. The driver needs this for calls
* to dma_unmap_sg.
*/
dma_addr_t nonsg_phys; /* Non scatter-gather physical address. */
/*
* data and dma_handle are the kernel virtual and bus address of the
* dma-able buffer containing the fcp_cmd, fcp_rsp and a scatter
* gather bde list that supports the sg_tablesize value.
*/
void *data;
dma_addr_t dma_handle;
struct sli4_sge *nvme_sgl;
dma_addr_t dma_phys_sgl;
/* cur_iocbq has phys of the dma-able buffer.
* Iotag is in here
*/
struct lpfc_iocbq cur_iocbq;
wait_queue_head_t *waitq;
unsigned long start_time;
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
uint64_t ts_cmd_start;
uint64_t ts_last_cmd;
uint64_t ts_cmd_wqput;
uint64_t ts_isr_cmpl;
uint64_t ts_data_nvme;
#endif
};
struct lpfc_nvme_fcpreq_priv {
struct lpfc_nvme_buf *nvme_buf;
};