linux_dsm_epyc7002/drivers/scsi/ibmvscsi/ibmvscsi.h
Brian King 0f33ece5bc [SCSI] ibmvscsi: Fix softlockup on resume
This fixes a softlockup seen on resume. During resume, the CRQ
must be reenabled. However, the H_ENABLE_CRQ hcall used to do
this may return H_BUSY or H_LONG_BUSY. When this happens, the
caller is expected to retry later. This patch changes a simple
loop, which was causing the softlockup, to a loop at task level
which sleeps between retries rather than simply spinning.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-07-27 12:03:46 -05:00

134 lines
4.0 KiB
C

/* ------------------------------------------------------------
* ibmvscsi.h
* (C) Copyright IBM Corporation 1994, 2003
* Authors: Colin DeVilbiss (devilbis@us.ibm.com)
* Santiago Leon (santil@us.ibm.com)
* Dave Boutcher (sleddog@us.ibm.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
* ------------------------------------------------------------
* Emulation of a SCSI host adapter for Virtual I/O devices
*
* This driver allows the Linux SCSI peripheral drivers to directly
* access devices in the hosting partition, either on an iSeries
* hypervisor system or a converged hypervisor system.
*/
#ifndef IBMVSCSI_H
#define IBMVSCSI_H
#include <linux/types.h>
#include <linux/list.h>
#include <linux/completion.h>
#include <linux/interrupt.h>
#include "viosrp.h"
struct scsi_cmnd;
struct Scsi_Host;
/* Number of indirect bufs...the list of these has to fit in the
* additional data of the srp_cmd struct along with the indirect
* descriptor
*/
#define MAX_INDIRECT_BUFS 10
#define IBMVSCSI_MAX_REQUESTS_DEFAULT 100
#define IBMVSCSI_CMDS_PER_LUN_DEFAULT 16
#define IBMVSCSI_MAX_SECTORS_DEFAULT 256 /* 32 * 8 = default max I/O 32 pages */
#define IBMVSCSI_MAX_CMDS_PER_LUN 64
/* ------------------------------------------------------------
* Data Structures
*/
/* an RPA command/response transport queue */
struct crq_queue {
struct viosrp_crq *msgs;
int size, cur;
dma_addr_t msg_token;
spinlock_t lock;
};
/* a unit of work for the hosting partition */
struct srp_event_struct {
union viosrp_iu *xfer_iu;
struct scsi_cmnd *cmnd;
struct list_head list;
void (*done) (struct srp_event_struct *);
struct viosrp_crq crq;
struct ibmvscsi_host_data *hostdata;
atomic_t free;
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;
};
/* a pool of event structs for use */
struct event_pool {
struct srp_event_struct *events;
u32 size;
int next;
union viosrp_iu *iu_storage;
dma_addr_t iu_token;
};
/* all driver data associated with a host adapter */
struct ibmvscsi_host_data {
atomic_t request_limit;
int client_migrated;
int reset_crq;
int reenable_crq;
struct device *dev;
struct event_pool pool;
struct crq_queue queue;
struct tasklet_struct srp_task;
struct list_head sent;
struct Scsi_Host *host;
struct task_struct *work_thread;
wait_queue_head_t work_wait_q;
struct mad_adapter_info_data madapter_info;
struct capabilities caps;
dma_addr_t caps_addr;
dma_addr_t adapter_info_addr;
};
/* routines for managing a command/response queue */
void ibmvscsi_handle_crq(struct viosrp_crq *crq,
struct ibmvscsi_host_data *hostdata);
struct ibmvscsi_ops {
int (*init_crq_queue)(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata,
int max_requests);
void (*release_crq_queue)(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata,
int max_requests);
int (*reset_crq_queue)(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata);
int (*reenable_crq_queue)(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata);
int (*send_crq)(struct ibmvscsi_host_data *hostdata,
u64 word1, u64 word2);
int (*resume) (struct ibmvscsi_host_data *hostdata);
};
extern struct ibmvscsi_ops iseriesvscsi_ops;
extern struct ibmvscsi_ops rpavscsi_ops;
#endif /* IBMVSCSI_H */